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Efficacy and safety of berberine plus 5-ASA for ulcerative colitis: A systematic review and meta-analysis
Efficacy and safety of berberine plus 5-ASA for ulcerative colitis: A systematic review and meta-analysis
Li Jilei Conceptualization Data curation Validation Writing – original draft Writing – review & editing 1
Zhang Chenchen Data curation Investigation Supervision Validation Writing – review & editing 2
Xu Yanchao Data curation Methodology Supervision 1
https://orcid.org/0009-0003-0575-0054
Yang Lili Conceptualization Investigation Writing – review & editing 3 *
1 Department of Oncology Diseases, Henan Province Hospital of Traditional Chinese Medicine, Zhengzhou, Henan, China
2 Graduate School Department, Beijing University of Chinese Medicine, Beijing, China
3 Henan Province Hospital of Traditional Chinese Medicine, Zhengzhou, Henan, China
Pullen Nicholas A. Editor
University of Northern Colorado, UNITED STATES OF AMERICA
Competing Interests: The authors have declared that no competing interests exist.

* E-mail: 15670259809@163.com
6 9 2024
2024
19 9 e030914416 1 2024
5 8 2024
© 2024 Li et al
2024
Li et al
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Purpose: This study aimed to assess the efficacy and safety of berberine(BBR) plus 5-aminosalicylic acid (5-ASA) for treating ulcerative colitis (UC). Methods: A comprehensive search was conducted in electronic databases, including Medline/PubMed, Sinomed, Embase, CNKI, Wanfang, and VIP, through January 2024 to identify all randomized controlled trials (RCTs) that administered BBR conjunction in standard therapy(5-ASA) for to support the treatment of UC. The data were synthesized using a meta-analysis approach with RevMan 5.4.1. The primary endpoint was the clinical efficacy rate. In contrast, the secondary endpoints included the Baron score, disease activity index (DAI) score, symptom relief latency, inflammatory markers, immunological indicators, and adverse events. Results: In this analysis, 10 RCTs comprising 952 patients with UC were examined. BBR considerably improved the clinical efficacy rate (RR = 1.22, 95% CI [1.15, 1.30], P < 0.00001), attenuated the Baron score (SMD = -1.72, 95% CI [-2.30, -1.13], P < 0.00001) and reduced the DAI score (SMD = -2.93, 95% CI [-4.42, -1.43], P < 0.00001). Additionally, it ameliorated clinical symptoms (SMD = -2.74, 95% CI [-3.45, 2.02], P < 0.00001), diminished inflammatory responses (SMD = -1.59, 95% CI [-2.14, 1.04], P < 0.00001), and modulated immune reactions (SMD = 1.06,95% CI [0.24,1.87], P <0.00001). Nonetheless, the impact of BBR on reducing adverse reactions was not statistically significant (RR = 0.75, 95% CI [0.42, 1.33], P > 0.05). Conclusion: BBR demonstrates substantial efficacy in treating UC without causing severe adverse reactions and may serve as a viable complementary therapy. However, its clinical application warrants confirmation by additional high-quality, low-bias RCTs.

The author(s) received no specific funding for this work. Data AvailabilityAll relevant data are within the manuscript and its Supporting Information files.
Data Availability

All relevant data are within the manuscript and its Supporting Information files.
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pmcIntroduction

Ulcerative colitis (UC) is an inflammatory bowel disease primarily manifesting as abdominal pain, diarrhea, and purulent, mucoid stools [1]. The etiology of UC is complex, predominantly affecting the rectum and sigmoid colon, with recurrent flare-ups and difficulty in achieving complete remission [2]. Globally incidence rates of UC are increasing; North America has reported prevalence rates between 139.8 and 286.3 per 100,000 individuals, while China has observed an incidence of approximately 11.6 per 100,000 individuals, indicating that UC is a substantial public health concern acknowledged by the World Health Organization (WHO) [3]. Regarding treatment for UC, mesalamine and sulfasalazine are integral to the 5-ASA medication class and constitute the cornerstone of clinical therapy for mild to moderate UC [4]. Progress in medical science has unveiled the effectiveness of immunosuppressive and corticosteroid drugs, with recent introductions of biological agents such as ustekinumab bringing forth novel therapeutic avenues [5]. Despite their benefits, these conventional treatments pose considerable challenges, including suboptimal mucosal healing, prohibitive costs, and a spectrum of adverse effects [6, 7], necessitating novel drug development for UC management. Current research posits that potent, nontoxic natural substances may be viable adjunctive treatments for standard UC therapy [8]. BBR, a potent alkaloid from Coptis chinensis and Phellodendron amurense, is noted for easing abdominal discomfort and diarrhea in UC treatment [9]. Empirical evidence from traditional Chinese medicine suggests that formulations including Coptis and Phellodendron lessen inflammatory responses, reducing symptomatology [10]. A meta-analysis of animal studies indicated that BBR reduces the DAI score and histological colitis score in UC animal models [11]. Mechanistically, BBR may exert its effects by decreasing myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels, reducing the expression of pro-inflammatory factors such as interleukin-1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α), and increasing the levels of the tight junction proteins zonula occludens-1 (ZO-1) and occludin. However, this animal study evaluated the efficacy of BBR, which does not directly guide its clinical application. As a commonly used adjunctive medication, the effectiveness of BBR combined with 5-ASA treatment for UC is still uncertain, and there is currently a lack of corresponding clinical research. What makes us even more curious is that Xu 2020 [12] believes that BBR is ineffective in improving diarrhea and bloody purulent stools in UC patients, which contradicts most of the existing research findings. Therefore, it is necessary to conduct further research to explore the efficacy of BBR combined with 5-ASA in treating UC. Our study aimed to evaluate the effects of BBR as an adjunct treatment on the efficacy and safety of UC.

Materials and methods

Search strategy

The methodology for this study was aligned with the Cochrane Handbook, and the reporting conformed to the PRISMA 2020 checklist [13] (S1 Checklist). This systematic review has been appropriately registered with the PROSPERO platform and assigned the identifier CRD42022376150. A comprehensive literature search was conducted across databases, including Medline/PubMed, Sinomed, Embase, CNKI, Wanfang, and VIP, imposing no linguistic constraints and spanning from their inception through January 2024. For the retrieval of literature, the search terms used were "ulcerative colitis", "ulcerative", "inflammatory bowel disease", "BBR", "BBR hydrochloride", "umbellate", "randomized" and "randomized controlled trial". All studies identified in the literature search are listed in S1 Table. The raw extracted data from the 10 included studies can be found in S2 Table.

The sequence used in the PubMed database was as follows:

#1: "ulcerative colitis" OR "ulcerative" OR "inflammatory bowel disease" [Mesh]

#2: "berberine" OR "berberine hydrochloride" OR "umbellatine" [Title/Abstract]

#3: #1 AND #2

#4: "randomized" OR "randomized controlled trial" [Title/Abstract]

#5: #3 AND #4

Inclusion criteria

(1) Study Participants: This study included individuals aged 18 years or older with a clinical diagnosis of UC according to the most recent diagnostic guidelines [14]. The inclusion criteria for Randomized Controlled Trials (RCTs) were as follows: (2) Intervention: The control group received standard 5-ASA treatment, while the treatment group was treated with a combination of 5-ASA and BBR. (3) Outcome measures include symptom relief (clinical efficacy rate); serological indicators (baron score, DAI assessment, symptom amelioration analysis, inflammatory cytokines, immune response); and safety profiles (adverse reactions).

Exclusion criteria

The following are the reasons for exclusion from this study: (1) were not Randomized Controlled Trials (RCTs), publications that have been duplicated, or articles with statistical inaccuracies (Original data not mentioned or statistical methods not referenced); (2)utilized animal models; (3) had inadequate original data or substantial missing key data; (4) The treatment group excluded literature on combining 5-ASA with other drugs.

Outcome measures

Primary outcome measures—Symptom relief

(1) The clinical efficacy rate was an essential metric for assessing the overall effectiveness of BBR in treating UC [15]. The clinical efficacy rate was assessed against the following benchmarks for therapeutic efficacy ① Complete remission, defined as a bowel movement frequency of three or fewer times per day, absence of bloody stools, abdominal pain, and diarrhea, coupled with colonoscopic evidence of mostly normal mucosa. ② Effective treatment is marked by pronounced improvement in clinical symptoms, a decreased presence of blood in stools, and mild mucosal inflammation or the appearance of pseudopolyps, as shown by colonoscopic examinations. ③ Ineffective treatment, defined as the absence of any discernible improvement in clinical symptoms, colonoscopy results, or pathological findings. The formula for calculating Total effectiveness is Total effectiveness = Number of complete remission + Number of effective cases / Total number of cases * 100% [16].

Secondary outcome measures—Serological indicators and safety profiles

Baron score: Evaluates the intestinal mucosal damage in patients with active UC [17]. The higher the Baron score, the more severe the colonic mucosal damage [18].

DAI: The average rectal bleeding score, stool frequency, and percentage weight change. A higher DAI score indicates more severe UC [19].

Symptom remission status: The duration over which patients experienced relief from abdominal pain, diarrhea, and pus-involving bloody stools [20].

Inflammatory cytokines: IL-6, IL-8, TNF-α, IL-10, IL-6, IL-8, and TNF-α levels decrease while IL-10 increases, indicating a reduction in UC’s inflammatory response [21].

Immune response: CD4+ T cells,CD8+ T cells,CD4+/CD8+ ratio. CD4+ and CD8+ T lymphocytes are distinct subpopulations that play pivotal roles in the immune response, with the CD4+/CD8+ ratio serving as a gauge of immune function in UC patients [22].

Adverse reactions.

Literature screening, data extraction, and quality assessment

By screening the titles and abstracts, two authors (Jilei Li and Chenchen Zhang) independently removed duplicate and irrelevant records. Any research discrepancies were addressed by consulting the third researcher, Yanchao Xu. After skimming complete text, articles not meeting the inclusion criteria or meeting the exclusion criteria were discarded. Two independent researchers summarized the extracted literature information into a table following standardized instructions. Data extraction included the first author, publication year, sample size, age, sex ratio, interventions, treatment method, treatment time, outcome, and source. If the data in the table were missing, they were not included. The assessment of the quality of the included studies was meticulously conducted following the Cochrane Handbook for Systematic Reviews of Interventions, version 5.4.1 [23], which provided a risk of bias-evaluation tool. We used version 2.0 of the Cochrane Risk-of-Bias (RoB) instrument for risk-of-bias assessment.

Statistical analysis

Our statistical analyses were performed with RevMan, which was tailored explicitly for conducting meta-analyses. Dichotomous variables were evaluated using relative risks (RRs), and continuous variables were assessed using the standard mean difference (SMD), both with accompanying 95% CI. In instances where heterogeneity tests yielded an I2 < 50%, indicating no significant heterogeneity among the groups, a fixed-effects model was applied. In contrast, a random effects model was adopted where significant heterogeneity (I2 > 50%) was detected, with P < 0.05 indicating statistical significance. The potential for publication bias was examined through the construction of funnel plots.

Results

Search results

The preliminary literature search retrieved a total of 1235 publications, distributed as follows: Medline/PubMed(169), Sinomed (77), Embase (138), CNKI (401), Wanfang (198), and VIP (152). An exhaustive screening process led to the inclusion of 10 RCTs in our study. The detailed flow of literature selection and the results thereof are depicted in Fig 1.

10.1371/journal.pone.0309144.g001 Fig 1 PRISMA flowchart of the study selection process.

Characteristics of the included studies

Our meta-analysis included 10 RCTs [24–33] enrolling 952 UC patients who were evenly divided into 476 in the treatment cohort and 476 in the control cohort. We meticulously extracted patient characteristics such as the first author, publication year, sample size, age, sex ratio, interventions, treatment method, treatment time, outcome, and source. These fundamental characteristics are delineated in Table 1.

10.1371/journal.pone.0309144.t001 Table 1 Characteristics of studies included in the meta-analysis.

ID	Sample Size	Age(E/C)mean or mean±SD	(Male/Female)(E/C)	Interventions(E)	Interventions(C)	Treatment Method	Treat Time /W	Outcome	Source	
Chen 2020 [24]	37/37	E: 33.87±3.42	E: 24/13	BBR: 0.2 g, tid	5-ASA	Oral	12	①⑥⑦⑧⑨	CNKI	
C: 34.02±3.44	C: (-)	5-ASA: 0.5 g, tid	0.5–1.0 g, tid	
Chen 2021 [25]	58/58	E: 35.7±9.60	E: 35/23	BBR: 2.0 g, tid	5-ASA	Enema	3	①②④⑨⑪	CNKI	
C: 35.2±9.80	C: 33/25	5-ASA: 2.0 g/d	0.5 g, qid	
Cheng 2022 [26]	68/68	E: 40.15±11.37	E: 39/29	BBR: 1.0 g, qid	5-ASA	Enema	8	①⑥⑧⑨	CNKI	
C: 39.55±1.26	C: 37/31	5-ASA: 0.2 g, tid	1.0 g, qid	
Cui 2021 [27]	47/47	E: 41.37±1.42	E: 24/23	BBR: 0.3 g, tid;	5-ASA	Oral	12	①②③④⑦	CNKI	
C: 41.01±1.13	C: 24/23	5-ASA: 1–2 g, tid	1.0 g, qid	
Gan 2020 [28]	32/32	E: 44.17±7.64	E: 18/14	BBR: 0.2g, tid	5-ASA	Oral	12	①②③⑤⑦	CNKI	
C: 44.53±8.29	C: 17/15	5-ASA: 4-6g/d	4–6 g/d	
Wang 2020 [29]	46/46	E: 39.77±6.49	E: 22/24	BBR: 0.2 g, tid	5-ASA	Oral	8	①⑥⑨⑪	CNKI	
C: 39.28±6.13	C: 25/21	5-ASA: 1.0 g, qid	1.0 g, qid	
Wang 2021 [30]	51/51	E: 47.52±5.36	E: 27/24	BBR: 0.2g, tid,	5-ASA	Oral	8	①⑤⑥⑦⑨⑩	CNKI	
C: 45.96±5.27	C: 28/23	5-ASA: 0.5–1 g, tid	0.5–1 g, tid	
Wei 2019 [31]	42/42	E: 52.31±3.17	E: 23/19	BBR: 0.3 g, tid	5-ASA 1.0 g, tid	Oral	4	①②③④⑦⑨⑩	CNKI	
C: 49.48±5.82	C: 23/19	5-ASA: 1 g, tid		
Xu 2020 [32]	55/55	E: 40.23±7.45	E: 31/24	BBR: 0.2 g, tid	5-ASA	Oral	8	①②③④⑤⑥⑦⑧⑨	VIP	
C: 36.86±5.32	C: 32/23	5-ASA: 1 g, tid	1 g, tid	
Zhu 2018 [33]	40/40	E: 37.87±4.12	E: 23/17	BBR: 0.2 g, tid	5-ASA	Oral	8	①②③④⑥⑦⑧⑨	CNKI	
C: 34.62±3.44	C: 22/18	5-ASA: 1 g, tid	1 g, tid	
E: Experimental C: Control BBR: Berberine g: Gram W: Week 5-ASA: Mesalazine/Sulfasalazine

① Total effective rate ② Time of loss of abdominal pain ③ Time of loss of pus and blood stool ④ Time of loss of Diarrhea ⑤ DAI ⑥ IL-6 ⑦ IL-8 ⑧ IL-10 ⑨ TNF-α ⑩ Baron ⑪ Adverse reactions

Quality assessment of the included studies

The quality evaluation of the selected studies included an examination of seven specific criteria, namely, selection bias, performance bias, detection bias, attrition bias, reporting bias, and any other possible sources of bias. Among them, four studies [27, 28, 30, 32] detailed the use of random number tables to generate random sequences, while the others mentioned the use of randomization without elaboration. Notably, no explicit descriptions of the allocation concealment methods used were provided. The specifics of the quality assessment are graphically represented in Fig 2. Bias risk assessment for individual studies is shown in S1 Fig.

10.1371/journal.pone.0309144.g002 Fig 2 Risk of bias summary.

Meta-analysis outcomes

Symptom relief—Clinical efficacy rate

In our meta-analysis, 8 articles [24–27, 29–31, 33], with a total of 778 patients, reported this rate. The studies were subjected to a fixed-effects model analysis because of the low heterogeneity (I2 = 0%, P < 0.99). BBR significantly enhanced the clinical efficacy of 5-ASA in managing UC compared with that of monotherapy (RR = 1.22, 95% CI [1.15, 1.30], P < 0.00001), as depicted in Fig 3.

10.1371/journal.pone.0309144.g003 Fig 3 Meta-analysis of clinical effective rate.

Serological indicators

(1) Baron score. Our research included data from 2 studies [30, 31] that included a cohort of 186 subjects and pre-provided and posttreatment Baron score. The results indicated substantial heterogeneity (I2 = 66%, P = 0.09). Employing a random-effects model to analyze the data revealed that patients receiving BBR plus 5-ASA had significantly greater Baron score than those treated with 5-ASA. The statistical relevance of these improvements was confirmed by a marked difference (SMD = -1.72, 95% CI [-2.30, -1.13], P < 0.00001), as illustrated in Fig 4.

10.1371/journal.pone.0309144.g004 Fig 4 Meta-analysis of Baron score.

(2) DAI assessment. Analysis of data from 4 studies [27, 30, 32] encompassing a sample of 390 patients revealed a high level of heterogeneity (I2 = 96%, P < 0.000001). The application of a random effects model demonstrated that compared with treatment with 5-ASA, BBR plus 5-ASA therapy significantly reduced the DAI score. This difference was statistically significant, as highlighted by the standardized mean difference (SMD = -2.93, 95% CI [-4.42, -1.43], P < 0.00001), as illustrated in Fig 5.

10.1371/journal.pone.0309144.g005 Fig 5 Meta-analysis of DAI score.

(3) Symptom amelioration analysis. 4 studies [25, 27, 32, 33] comprising 285 patients reported the duration of abdominal pain relief, showing a significant degree of heterogeneity (I2 = 95%, P < 0.00001). A random-effects model analysis revealed that BBR significantly shortened the duration of abdominal pain (P < 0.00001). Similarly, 4 studies [25, 27, 32, 33] documented the duration of diarrhea relief in a cohort of 285 patients, showing substantial heterogeneity (I2 = 96%, P < 0.00001). The results indicated that BBR significantly reduced the duration of diarrhea (P < 0.00001). Another set of 4 studies [25, 27, 32, 33] discussing the duration of hematochezia relief in 285 patients indicated high heterogeneity (I2 = 97%, P < 0.00001), with the random-effects model demonstrating that BBR meaningfully shortened the duration of relief (P = 0.0004). These findings suggest that BBR can effectively adjunctive treat UC by attenuating symptoms such as abdominal pain, diarrhea, and hematochezia (SMD = -2.74, 95% CI [-3.45, 2.02], P < 0.00001) as illustrated in Fig 6.

10.1371/journal.pone.0309144.g006 Fig 6 Meta-analysis of clinical symptoms.

(4) Inflammatory cytokines. 6 studies [24, 26, 28, 30, 32, 33] assessing the serum IL-6 concentration in a cohort of 328 patients revealed substantial heterogeneity (I2 = 67%, P = 0.009). Using a random-effects model, the study revealed that treatment with BBR resulted in a significant decrease in IL-6 expression, which was statistically significant (P < 0.00001). 7 studies [24, 26, 28, 30–33] reported on IL-8 levels across 366 participants, indicating pronounced heterogeneity (I2 = 83%, P < 0.00001). The results of these studies confirmed that BBR significantly inhibited the expression of IL-8, a notable proinflammatory mediator (P < 0.00001). In addition, 3 studies [24, 32, 33] focusing on IL-10 levels in 264 subjects showed minimal heterogeneity (I2 = 0%, P = 1.00). Unlike IL-6, IL-8, and TNF-α, IL-10 is a common anti-inflammatory factor. IL-10 is a common anti-inflammatory factor, and the higher its expression level, the milder the inflammatory response [34]. 3 studies [24, 32, 33] suggested that compared to the use of 5-ASA alone, the combination of BBR and 5-ASA can increase the expression of IL-10, helping to alleviate the inflammatory response in patients with UC. These studies suggest that BBR administration reduces the levels of the anti-inflammatory cytokine TNF-α in patients with UC (P < 0.00001). Finally, an examination of TNF-α concentrations, as reported by 8 studies [24, 26, 28, 30–33] involving 858 patients, revealed substantial heterogeneity (I2 = 84%, P < 0.00001). Subsequent analysis with the random effects model confirmed that BBR significantly lowered the serum TNF-α concentration, a finding of statistical and clinical relevance (P < 0.00001). These collective results underscore the efficacy of BBR in modulating inflammatory cytokines, thereby delineating its therapeutic potential in the management of UC; these findings are corroborated by statistically significant data [SMD = -1.59, 95% CI [-2.14, -1.04], P < 0.00001), as depicted in Fig 7.

10.1371/journal.pone.0309144.g007 Fig 7 Meta-analysis of inflammatory cytokines.

(5) Immune response. An analysis of 2 studies [26, 28] encompassing a sample of 264 patients demonstrated minimal heterogeneity (I2 = 0%, P = 0.34) and revealed that BBR administration resulted in a significant increase in CD4+ T cells (P < 0.00001). The increase in CD4+ T cells may promote an increase in the number of regulatory T cells, which helps alleviate the inflammatory response in UC. Similarly, 2 studies [26, 28] assessing CD8+ T cells in the same patient cohort reported low heterogeneity (I2 = 37%, P = 0.21). The data showed that the combination of BBR with 5-ASA did not significantly alter the percentage of CD8+ T cells compared to the effect of 5-ASA alone (P = 0.50). Moreover, statistics regarding the CD4+/CD8+ ratio from the studies above exhibited considerable heterogeneity (I2 = 81%, P = 0.02). Using a random effects model for analysis indicated a significant increase in the CD4+/CD8+ ratio, which suggested an improvement in immune function (P = 0.0001). These data suggest that BBR has the potential to favorably alter the immune response in the context of UC management. The therapeutic implications of these modifications are statistically significant and substantiated by the standardized mean difference [SMD = 1.06, 95% CI [0.24, 1.87], P < 0.00001], as depicted in Fig 8.

10.1371/journal.pone.0309144.g008 Fig 8 Meta-analysis of CD4+ T cells, CD8+ T cells, CD4+/CD8+ ratio.

Safety profiles—Adverse reactions

An analysis of four studies [24–26, 29] documented adverse effects, including nausea, vomiting, rash, and abdominal bloating, across a cohort of 418 patients. Within this cohort, adverse reactions occurred in 18 patients in the treatment group and 24 in the control group. The aggregated data reflected minimal heterogeneity (I2 = 0%, P = 0.84). An analysis conducted through a fixed-effects model indicated a lack of significant differences in the occurrence of adverse reactions between the BBR treatment group and the control group (RR = 0.75, 95% CI [0.42, 1.33]; P = 0.32), as illustrated in Fig 9.

10.1371/journal.pone.0309144.g009 Fig 9 Meta-analysis of adverse reactions.

Sensitivity analysis

A sensitivity analysis of the effectiveness of BBR in treating UC was performed by systematically excluding individual studies and reassessing the outcomes. The recalculated data showed no noteworthy differences from the original findings (P > 0.05), thereby confirming the robustness of the meta-analysis.

Bias risk assessment

The assessment of publication bias in the clinical efficacy of BBR for treating UC was conducted through funnel plot analysis. This analysis employed the RR of the consolidated studies on the x-axis against the inverse of their log (RR) on the y-axis. The statistical analysis suggested the presence of potential publication biases in the compiled research, as depicted in Fig 10.

10.1371/journal.pone.0309144.g010 Fig 10 Clinical effective rate funnel chart.

Discussion

UC is a complex gastrointestinal disease characterized by recurrent episodes and challenging management, profoundly affecting patients’ quality of life [35]. BBR can be a safe and productive complementary intervention to support UC disease management. It can potentially attenuate symptoms, including abdominal pain and diarrhea, improving patient outcomes [36]. Xiong et al. [37] demonstrated through mouse experiments that BBR can improve intestinal mucosal damage, promote mucosal healing, and alleviate symptoms such as diarrhea and bloody stools. Moreover, BBR facilitates the modulation of immune functions in UC mice by activating the IL-4/STAT6 signaling pathway, inhibiting M1 macrophages, and promoting M2 macrophages [38]. M1 and M2 macrophages can influence the differentiation of CD4+ and CD8+ T cells by producing factors like TNF-α and IL-10, thereby regulating the immune function in UC mice and suppressing excessive inflammatory responses [39]. Li et al. [40] research suggested that BBR can alleviate the inflammatory response in a cat model of UC, reduce inflammatory factors, and improve conditions of diarrhea and bloody stools. Li et al. further mechanistic studies showed that BBR can decrease Bacteroidetes and increase Firmicutes in DSS-treated cats. BBR reshaped the microbiota composition by reducing the abundance of Proteobacteria. Our study provides evidence suggesting that the application of BBR plus 5-ASA for treating UC may augment clinical efficacy, diminish Baron endoscopic score, decrease DAI score, ameliorate clinical manifestations, alleviate inflammatory processes, and adjust immune responses. Nonetheless, its role in mitigating adverse reactions is not significant.

Our analysis systematically addresses the data in three domains: symptom relief, serological indicators, and safety profiles. Focusing initially on symptom relief, prior investigations have indicated that BBR-containing traditional Chinese medicine formulations may significantly improve the clinical efficacy of UC management. Our extensive research, incorporating data from 778 subjects, robustly corroborates that BBR adjunct therapy substantially enhances clinical response rates among UC patients. Mucosal healing within the intestinal tract is a critical indicator of UC activity [41]. The Baron score is an indicator used to assess the severity of intestinal mucosal bleeding [42]. Our study also suggested that combining BBR with 5-ASA treatment can reduce the Baron score in patients with UC, thereby improving the condition of the intestinal mucosa.

Converging evidence suggests that patients who achieve mucosal healing tend to exhibit higher rates of sustained remission and a diminished risk of relapse, a trend competently captured by the Baron endoscopic score—wherein a lower score signifies more favorable mucosal recovery [18].

The results of the endoscopic assessments in our study suggest that following BBR intervention, BBR is instrumental in lowering the Baron score, hence fostering mucosal restitution. Furthermore, BBR can reduce the DAI score and shorten the duration of symptoms such as diarrhea, rectal bleeding, and abdominal pain, indicating that BBR as a supplementary treatment has a specific efficacy in managing UC. Considering these outcomes, we postulate that there is a correlation between the reduction in patients’ Baron score, therapeutic effectiveness, and symptom relief. BBR facilitates intestinal mucosal recovery, leading to a concomitant decrease in the Baron score; tangible symptom alleviation—specifically, in abdominal discomfort and diarrhea—is observed, culminating in discernible advances in UC treatment efficacy.

Emerging research has demonstrated a significant association between systemic inflammatory cytokine levels and the progression of UC. Increased concentrations of proinflammatory cytokines such as IL-6, IL-8, and TNF-α indicate heightened disease severity, whereas elevated IL-10 levels typically signal a mitigated disease state [43]. Research has shown that upon exposure to chemical or environmental triggers, intestinal epithelial cells prompt monocytes to secrete IL-8 [44]. This event initiates the activation of NF-κB, culminating in the activation of macrophages, a process that initiates the sequential release of proinflammatory mediators, notably TNF-α and IL-6 [45]. Notably, the anti-inflammatory cytokine IL-10 counters this effect by restraining the transcription and secretion of inflammatory factors by activated monocytes [46]. Our meta-analysis evaluated multiple inflammatory cytokines, and the evidence suggested that BBR potentially mitigates UC symptoms by attenuating the proinflammatory mediators IL-6, IL-8, and TNF-α and concurrently increasing IL-10 expression. By doing so, it appears to modulate inflammatory homeostasis within the organism.

Disproportionate inflammatory processes derail the body’s immune equilibrium, invigorating T lymphocytes. Naive CD4+ T cells and naive CD8+ T cells become activated and differentiate into effector cells and/or memory cells [47]. Notably, CD4+ T cells can activate and differentiate an immature effector/memory CD4+ T cells phenotype, executing immune responses corresponding to their specific cell phenotypes [48]. At the same time, the increase in CD4+ T cells can maintain intestinal immune balance, reducing gut damage and inflammation in UC patients through immune surveillance and promoting inflammatory repair mechanisms [49]. CD8+ T cells—widely recognized as cytotoxic T lymphocytes—can directly eliminate pathogen-infected cells [50]. Under normal circumstances, the CD4+/CD8+ ratio decreases between 1 and 2, indicating healthy immune function. An imbalance in the CD4+/CD8+ ratio could exacerbate the inflammatory condition in patients with UC [51]. In this context, our findings revealed that BBR can favorably modulate the levels of CD4+ T cells, CD8+ T cells, and CD4+/CD8+ ratio, thereby improving immunological functions. The enhancement of immune functions not only includes the strengthening of immune responses in areas such as the gut mucosa, making it more effective in defending against pathogens but also in mitigating excessive inflammatory responses, thereby preventing damage to tissues [52]. In turn, this can alleviate the suffering of patients with UC. The study did not report the key immunological factors FOXP3 and CD25. FOXP3, as a primary marker of regulatory T cells, plays an essential role in the suppressive function of Tregs [53]. Research by Zhang et al. suggested that reduced expression of FOXP3 in the intestinal tissues of UC patients may lead to an imbalance in immune regulation, exacerbating pathological conditions and inflammatory responses [54]. Similarly, a decrease in CD25 expression could weaken the suppressive capabilities effects of Tregs, further aggravating the pathological conditions and inflammation in UC [55].

The safety of BBR treatment for UC also warrants attention, with a focus on common symptoms such as nausea, abdominal pain, dyspepsia, constipation, and bloating. Our findings confirm the absence of significant adverse effects of BBR plus 5-ASA, confirming its favorable safety profile. However, this study has certain limitations. For example, all articles in the meta-analysis originated from China/Asia, which limits the generalizability of the results. Additionally, there is variability in the administration routes and treatment duration across different studies, which may limit the application of BBR as an adjunctive treatment.

Conclusion

The research results reported in this article suggest that BBR plus 5-ASA for the treatment of UC is a safe and effective intervention. Nevertheless, the validity of these results is tempered by the constrained scope and caliber of the included studies, characterized by an absence of reporting on allocation concealment, blinding, and a scarcity of longitudinal follow-up. Therefore, interpreting the long-term therapeutic benefits of BBR with circumspection is imperative. This inquiry points to the promising role of BBR in improving UC but underlines the necessity for future research endeavors. There is a profound need for strategically designed, expansive, multi-institutional, high-caliber RCTs to consolidate and expand upon these preliminary findings.

Supporting information

S1 Checklist PRISMA 2020 checklist.

(DOCX)

S1 Table All Studies identified in the literature search.

(XLSX)

S2 Table Raw data for meta-analysis.

(XLSX)

S1 Fig Bias risk assessment for individual studies.

(TIF)

We would like to thank AJE (https://china.aje.com/cn) for English language editing.

10.1371/journal.pone.0309144.r001
Decision Letter 0
Pullen Nicholas A. Academic Editor
© 2024 Nicholas A. Pullen
2024
Nicholas A. Pullen
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version0
20 Feb 2024

PONE-D-24-02154Efficacy and safety of berberine for ulcerative colitis: A systematic review and meta-analysisPLOS ONE

Dear Dr. Yang,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please respond to each of the reviewer comments, including the detailed uploaded response provided by Reviewer 1. I concur that all of the criticisms provided by the reviewers are necessary and constructive. In addition to the reviewers' comments, I have the following points that should be addressed.

First, I must emphasize a couple of important issues raised in the review process noticed by multiple parties including the reviewers and myself: (1) that some of the subject studies are not in English is a barrier to many other researchers; (2) overstatement of claims about use context of berberine (BBR). The latter issue can be addressed by carefully moderating the language of the manuscript (including title) to indicate the actual use of BBR here as a complementary therapeutic. The former issue can be addressed in a variety of ways, one which will improve PRISMA reporting. You note that data, code, and other materials are not available in the PRISMA checklist, which is not best practice for PLOS or principles of open science broadly. Providing such information from all studies and translated (with publisher permission) from the non-English studies could ameliorate both the Chinese language and PRISMA issues.

Additionally, I have the following questions comments that should be addressed:

Regarding the section on adverse events, did any of the studies report glycemic control indicators (glucose, insulin, HOMA-IR, etc.) or changes in body mass/weight?

I think that you need to carefully re-visit the T cell section. First, the claim that BBR “augmented” CD8+ is not supported by simple visual inspection of the data; further even if some statistical test alleges significant difference here, it is not supported by the actual numbers/biology whose differences are not truly substantive.   Second, CD4+ changes could include changes in T regulatory (Treg) cell populations. Did any studies report FOXP3 and/or CD25 expression? This should be examined and discussed, even if none of the reported studies indicated such. These are important cells to consider in pathologies such as UC. Finally, what do increased CD4+ mean in the context of “favours control” as depicted in the figure? The statements and the figure do not seem to be in agreement. Without further details as to the phenotypes of CD4+ T cells, once cannot really say much about favoring one group vs. another; for example, an increase in Th17 cells could actually indicate worsening of cellular pathology, where as an increase in Treg may indicate amelioration.

Line 120: be more detailed as to what is meant by “statistical inaccuracies”.

Lines 148-152 need to be re-written to indicate the subject studies used these techniques. As currently written the statements could be construed that you conducted these experiments.

Table 1 descriptors need to be re-written in English.

I suggest combining Figures 3, 4, and 5 into a single figure.

Lines 256-257: more should be stated about the IL-10 results, particularly discordance between control and BBR intervention.

Delete the first sentence of line 340. It is unnecessary.

There are currently no detailed figure legends. This should be addressed.

Please submit your revised manuscript by Apr 01 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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Nicholas A. Pullen, Ph.D.

Academic Editor

PLOS ONE

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Additional Editor Comments (if provided):

Dear Dr. Yang,

Please respond to each of the reviewer comments, including the detailed uploaded response provided by Reviewer 1. I concur that all of the criticisms provided by the reviewers are necessary and constructive. In addition to the reviewers' comments, I have the following points that should be addressed.

First, I must emphasize a couple of important issues raised in the review process noticed by multiple parties including the reviewers and myself: (1) that some of the subject studies are not in English is a barrier to many other researchers; (2) overstatement of claims about use context of berberine (BBR). The latter issue can be addressed by carefully moderating the language of the manuscript (including title) to indicate the actual use of BBR here as a complementary therapeutic. The former issue can be addressed in a variety of ways, one which will improve PRISMA reporting. You note that data, code, and other materials are not available in the PRISMA checklist, which is not best practice for PLOS or principles of open science broadly. Providing such information from all studies and translated (with publisher permission) from the non-English studies could ameliorate both the Chinese language and PRISMA issues.

Additionally, I have the following questions comments that should be addressed:

• Regarding the section on adverse events, did any of the studies report glycemic control indicators (glucose, insulin, HOMA-IR, etc.) or changes in body mass/weight?

• I think that you need to carefully re-visit the T cell section. First, the claim that BBR “augmented” CD8+ is not supported by simple visual inspection of the data; further even if some statistical test alleges significant difference here, it is not supported by the actual numbers/biology whose differences are not truly substantive. Second, CD4+ changes could include changes in T regulatory (Treg) cell populations. Did any studies report FOXP3 and/or CD25 expression? This should be examined and discussed, even if none of the reported studies indicated such. These are important cells to consider in pathologies such as UC. Finally, what do increased CD4+ mean in the context of “favours control” as depicted in the figure? The statements and the figure do not seem to be in agreement. Without further details as to the phenotypes of CD4+ T cells, once cannot really say much about favoring one group vs. another; for example, an increase in Th17 cells could actually indicate worsening of cellular pathology, where as an increase in Treg may indicate amelioration.

• Line 120: be more detailed as to what is meant by “statistical inaccuracies”.

• Lines 148-152 need to be re-written to indicate the subject studies used these techniques. As currently written the statements could be construed that you conducted these experiments.

• Table 1 descriptors need to be re-written in English.

• I suggest combining Figures 3, 4, and 5 into a single figure.

• Lines 256-257: more should be stated about the IL-10 results, particularly discordance between control and BBR intervention.

• Delete the first sentence of line 340. It is unnecessary.

• There are currently no detailed figure legends. This should be addressed.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: I Don't Know

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: There is an attached review file with detailed comments by line/section of the article. However, below are a few general comments:

Overall, I think this analysis is of interest to the field and a good contribution to the literature. However, there are a few overarching concerns (“General Comments”) that must be addressed before I can recommend for the publication, in addition to a detailed breakdown of items associated with each section of the manuscript (“Detailed Comments”) in the attached review file.

GENERAL COMMENTS (again, PLEASE see detailed comments in the attached review file).

1. There are many locations where the authors overstate the findings/context of the study to implicate “BBR as a therapy for UC” when the study actually evaluates the efficacy of “BBR as a complementary therapy to support/enhance standard treatments.” Because BBR is being used in addition to standard treatment in all studies and is not being used alone in comparison to standard treatment, you are not evaluating BBR as an alternative therapy. So, in locations where it is implied the study is evaluating BBR in "treating disease,” it should be reworded to something like, "supporting disease management". The locations of these overstatements in the manuscript are highlighted in detail in “Detailed Comments.”

2. Many issues with citations: There is a considerable lack of citations for physiological and mechanistic statements throughout the article. These are highlighted in detail in “Detailed Comments.” Also, two of the ten articles included in the analysis are not properly cited in the References (in-text Figures include different author names for references 22 and 24)

3. Need additional details in Methods for reproducibility (These are highlighted in detail in “Detailed Comments.”), especially around data extraction and additional clarity around the inclusion criteria.

4. The lack of availability of many of these articles in the English language and/or on many databases common to Europe and the Americas presents a major barrier to researchers outside of China/Asia who may want to follow up on these articles. I unsuccessfully tried to search for many of these articles through Medline, EMBASE, PubMed, Google Scholar, and three separate university libraries for institutions that I am affiliated with (one of them being a major medical school library)—so, I was unable to confirm many methods or double-check measures. Because of this, authors must include which database they accessed each article from and any identifiable database numbers (e.g., DOI) in Table 1 to facilitate the reproducibility of the search and access to these papers.

5.In the introduction, authors must place the current review/meta-analysis in the context of any existing systematic reviews and meta-analysis on similar content (which do exist)—Describe what content those reviews/meta-analysis include, and how this current meta-analysis is different and contributes to the literature.

6. Highlight limitations in discussion or conclusion

Reviewer #2: 1. Authors should provide more detailed information on the sources of BBR in each study.

2. It is recommended to include the UC pathological staging of patients before treatment in the study.

3. Please calibrate the reference format in the manuscript to maintain consistency.

4. The title is "Efficacy and safety of berberine for ulcerative colitis: A systematic review and meta-analysis", but the majority of the data included in the meta-analysis is related to the combined treatment of BBR and 5-ASA. How to demonstrate the efficacy and safety of BBR through the use of BBR in combination with 5-ASA data? Please use concise and succinct language to describe your research findings regarding this matter.

**********

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Reviewer #1: No

Reviewer #2: No

**********

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Attachment Submitted filename: PLOS One Review_ BBR and UC.docx

10.1371/journal.pone.0309144.r002
Author response to Decision Letter 0
Submission Version1
4 Jun 2024

Dear Editors and Reviewers:

We gratefully appreciate the editors and all reviewers for their time spent making positive and constructive comments. These comments are all valuable and helpful for revising and improving our manuscript entitled “Efficacy and safety of berberine plus 5-ASA for ulcerative colitis: A systematic review and meta-analysis” (PONE-D-24-02154).

We have made our utmost efforts to improve the manuscript in the following ways: (1) avoiding overestimating the effects of berberine and accurately describing its effects; (2) adding necessary citations; (3) supplementing explanations or rewriting parts that are difficult to understand. These revisions will help enhance the overall quality of the manuscript. The reviewer comments are laid out below in italicized font and specific concerns have been numbered. We have studied comments carefully and have made corrections which we hope meet with approval. Our response is given in normal font and changes/additions to the manuscript are given in red.

Thank you and best regards.

Yours sincerely,

Lili Yang

Kaifeng Central Hospital

Responses to Reviewers

Editor Comments

Comment 1: Some of the subject studies are not in English is a barrier to many other researchers.

Response 1: Thank you for your comment. We were sorry for our careless mistakes. We have already changed the non-English text below Table 1 to English text. (line 188-190 on page 10).

Comment 2: overstatement of claims about use context of berberine

Response 2: We would like to express our sincere gratitude for your professional review of our article. Your feedback and suggestions were very helpful and insightful. You are such a patient and responsible reviewer, and I feel very honored to have your assistance. Based on your suggestion, we have made revisions. When describing the effects of berberine, we have rephrased our wording to avoid overstating the effects of berberine. For example, we have used phrases like "BBR as a safe and efficacious complementary intervention to support disease management", "BBR in conjunction with standard therapy to support the treatment of UC", "Berberine plus 5-ASA for ulcerative colitis ", "BBR demonstrates substantial efficacy in treating UC without causing severe adverse reactions and may serve as a viable complementary therapy” to accurately express the effects of berberine.

(line 1 on page 1), (line 41-42 on page 2), (line 247 on page 12), (line 409-410 on page 18) et al.

Comment 3: Regarding the section on adverse events, did any of the studies report glycemic control indicators (glucose, insulin, HOMA-IR, etc.) or changes in body mass/weight?

Response 3: Thanks for your comment. We have carefully read the literature included this time, however, we did not find any studies that reported these indicators. The issue you mentioned is interesting, and we will focus on it in our future research.

Comment 4: I think that you need to carefully re-visit the T cell section. First, the claim that BBR “augmented” CD8+ is not supported by simple visual inspection of the data; further even if some statistical test alleges significant difference here, it is not supported by the actual numbers/biology whose differences are not truly substantive.

Response 4 Thank you for your professional and meticulous review; we apologize for our oversight. The expression "augmented CD8+" was incorrect. After reevaluating, we have revised the sentence in the manuscript from " The data indicated that BBR significantly augmented CD8+ T cells (P < 0.00001)" to "The data indicated that combining BBR with 5-ASA does not significantly alter the expression of CD8+ T cells compared to using 5-ASA alone." We thank you again for your expert guidance. (line 281-283 on page 14).

Comment 5: Second, CD4+ changes could include changes in T regulatory (Treg) cell populations. Did any studies report FOXP3 and/or CD25 expression? This should be examined and discussed, even if none of the reported studies indicated such. These are important cells to consider in pathologies such as UC.

Response 5: Thank you for your professional review. While the original study did not report on the expression of FOXP3 and/or CD25, these elements are crucial. Following your advice, we have added related discussions in the manuscript. The specific additions are as follows: "Regrettably, the study did not report key immunological factors, FOXP3 and CD25. FOXP3, serving as the principal marker for Tregs, is critical for their suppressive function[1]. Research by Zhang et al. suggests that diminished expression of FOXP3 in the intestinal tissues of UC patients may lead to an imbalance in immune regulation, exacerbating the pathological conditions and inflammatory responses[2]. Similarly, reduced expression of CD25 can weaken the inhibitory capacity of Tregs, aggravating the pathology and inflammation associated with UC[3]." (line 391-398 on page 18).

Comment 6: Finally, what does increased CD4+ mean in the context of “favours control” as depicted in the figure?

Response 6: Thank you for your guidance. We have not expressed ourselves before, but with your help, we can now articulate more precisely, as follows: "The increase in CD4+ T cells may promote an increase in the number of regulatory T cells, which helps alleviate the inflammatory response in UC." Additionally, we have made modifications to the manuscript accordingly. (line 278-280 on page 13 ).

Comment 7:The statements and the figure do not seem to be in agreement.

Response 7:Thank you for your comment. We are sorry for our carelessness. We have rechecked and made specific modifications as follows: Firstly, change (I2 = 81%, P < 0.00001) into (I2 = 81%, P = 0.02). Change (P = 0.0004) into (P = 0.0001). Additionally, we have changed “The data indicated data that BBR significantly augmented CD8+ T cells (P < 0.00001).” to “The data showed that combining BBR with 5-ASA does not significantly alter the expression of CD8+ T cells compared to using 5-ASA alone(P = 0.50).” (line 282-284 on page 14).

Comment 8:Without further details as to the phenotypes of CD4+ T cells, one cannot really say much about favoring one group vs. another; for example, an increase in Th17 cells could actually indicate worsening of cellular pathology, whereas an increase in Treg may indicate amelioration.

Response 8:Thank you for your detailed comments and professional guidance. As you pointed out, CD4+ T cells include both T effector cells (such as Th1, Th2, Th17, etc.) and T regulatory cells, which are immunosuppressive. They have different physiological functions; for instance, an increase in Th17 cells may indicate the progression of UC, while an increase in Treg cells may suggest a mitigation of UC. We revisited the article and realized that the mentioned CD4+ T cell compartment includes both T effector cells and T regulatory cells. At the same time, we also provide the DOI or link of the articles in the references for easy access by the readers.

Comment 9: Lines 148-152 need to be re-written to indicate the subject studies used these techniques. As currently written the statements could be construed that you conducted these experiments.

Response 9:Thank you for your reminder; your guidance has been immensely helpful. You also mentioned in the following comment that this section was overly detailed and suggested we streamline it. The revised content is as follows:

(4) Inflammatory cytokines: IL-6, IL-8, TNF-α, IL-10. Levels of IL-6, IL-8, and TNF-α decrease, while IL-10 increases, indicating a reduction in the inflammatory response of UC.

(5) Immune response: CD4+ T cells, CD8+ T cells, CD4+/CD8+ ratio. CD4+ and CD8+ T lymphocytes are distinct subpopulations that play pivotal roles in the immune response, with the CD4+/CD8+ ratio serving as a gauge of immune function in UC patients. (6) Adverse reaction.(line 139-146 on page 6).

Comment 10 Table 1 descriptors need to be re-written in English.

Response 10hank you for your comment. We were sorry for our careless mistakes. We have already changed the non-English text below Table 1 to English text. (line 188-190 on page 10).

Comment 11 I suggest combining Figures 3, 4, and 5 into a single figure.

Response 11 Thank you for your suggestion. Figures 3, 4, and 5 represent the clinical efficacy rate, Baron score, and DAI score, respectively. Each represents different aspects, hence separating them into individual charts will make the results clearer. Therefore, we have decided not to combine them, but we equally appreciate your valuable suggestion.

Comment 12 Lines 256-257: more should be stated about the IL-10 results, particularly discordance between control and BBR intervention.

Response 12Thank you for your guidance, we have added the following content.

IL-10 is a common anti-inflammatory factor, and the higher its expression level, the milder the inflammatory response. 3 studies suggest that compared to using 5-ASA alone, the combination of BBR and 5-ASA can increase the expression of IL-10, helping to alleviate the inflammatory response in patients with UC. (line 261-264 on page 13).

Comment 13 Delete the first sentence of line 340. It is unnecessary.

Response 13 Thank you for your professional guidance, we have already removed that sentence.

Comment 14 There are currently no detailed figure legends. This should be addressed.

Response 14Thank you for the reminder. We have already placed each figure legend directly after the paragraph in which they are first mentioned.

Journal Requirements:

Comment 15 Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming.

Response 15 Thank you for your guidance; we have revised the style of the manuscript according to the requirements, including those for file naming.

Comment 16. Please include your tables as part of your main manuscript and remove the individual files. Please note that supplementary tables (should remain/ be uploaded) as separate "supporting information" files.

Response 16 Thank you for your meticulous guidance on formatting. We have placed Table 1 in the manuscript as per your instructions. (line 187-190 on page 9-10).

Reviewer #1:

GENERAL COMMENTS

Comment 1: There are many locations where the authors overstate the findings/context of the study to implicate “BBR as a therapy for UC” when the study actually evaluates the efficacy of “BBR as a complementary therapy to support/enhance standard treatments.” a. Because BBR is being used in addition to standard treatment in all studies and is not being used alone in comparison to standard treatment, you are not evaluating BBR as an alternative therapy. So, in locations where it is implied the study is evaluating BBR in "treating disease,” it should be reworded to something like, "supporting disease management".

Response 1: We would like to express our sincere gratitude for your professional review of our article. Your feedback and suggestions were very helpful and insightful. You are such a patient and responsible reviewer, and I feel very honored to have your assistance. Based on your suggestion, we have made revisions. When describing the effects of berberine, we have rephrased our wording to avoid overstating the effects of berberine. For example, we have used phrases like "BBR as a safe and efficacious complementary intervention to support disease management" and "BBR in conjunction with standard therapy to support the treatment of UC" to accurately express the effects of berberine. (line 1 on page 1), (line 41-42 on page 2), (line 247 on page 12), (line 409-410 on page 18)et al.

Comment 2: Many issues with citations: There is a considerable lack of citations for physiological and mechanistic statements throughout the article. These are highlighted in detail in “Detailed Comments.” Also, two of the ten articles included in the analysis are not properly cited in the References (in-text Figures include different author names for references 22 and 24)

Response 2: Thank you for reading our paper so carefully. We have added citations in the section on physiological and mechanistic statements. Additionally, we have made modifications to the original references 22 and 24 to ensure that the citations are more standardized. After our revisions, the article now cites approximately 20 more references than the previous version. A detailed response will be provided below the comments of the first reviewer.

Comment 3: Need additional details in Methods for reproducibility (These are highlighted in detail in “Detailed Comments.”), especially around data extraction.

Response : Thank you for your valuable guidance on the manuscript. We have supplemented the methods as requested. The following paragraph is the revised content:

"By screening the titles and abstracts, two authors (Jilei Li and Chenchen Zhang) independently removed duplicate and irrelevant records. Any discrepancies between the researchers were addressed by consulting the third researcher Yanchao Xu. After skimming the full text, articles not meeting the inclusion criteria or meeting the exclusion criteria were discarded. Two independent researchers summarized the extracted literature information into a table following standardized instructions. Data extraction includes the first author, publication year, sample size, age, sex ratio, interventions, treatment method, treatment time, outcome, and source. If the data in the table is missing, it will not be included. The assessment of the quality of the included studies was meticulously conducted following the Cochrane Handbook for Systematic Reviews of Interventions, version 5.4.1, which provided a risk of bias-evaluation tool. We used version 2.0 of the Cochrane Risk-of-Bias (RoB) instrument for risk of bias assessment.” (line 150-157 on page 7).

Comment 4: The lack of availability of many of these articles in the English language and on many databases common to Europe and the Americas presents a major barrier to researchers outside of China/Asia who may want to follow up on these articles. I unsuccessfully tried to search for many of these articles through Medline, EMBASE, PubMed, Google Scholar, and three separate university libraries for institutions that I am affiliated with (one of them being a major medical school library)—so, I was unable to confirm many methods or double-check measures. Because of this, authors must include which database they accessed each article from and any identifiable database numbers (e.g., DOI) in Table 1 to facilitate the reproducibility of the search and access to these papers.

Response 4: Thank you for your professional guidance. We apologize for any inconvenience our layout may have caused. We also appreciate your suggestions. However, placing the DOI or LINKs in Table 1 would require additional space and could detract from the table's appearance. Therefore, we have uploaded the DOIs or LINKs as an attachment, titled "DOI OR LINK." We have also listed the DOIs or LINKs below for your reference.

1. Chen 2020：DOI: 10.14164/j.cnki.cn11-5581/r.2020.10.063

LINK:https://kns.cnki.net/kcms2/article/abstract?v=yqeyU9EK6jT70Eh65eKmwK43ydBlFTIDStH0jexxpkVk6vtooH0y2vfgnSk_B8W9hkQO6HVgO9u3iA0BsjexoPSd_J--WD0t21BYlntP4Mda8D3jrgtTQzfcJnacYUHIrh04FGHrhFw=&uniplatform=NZKPT&language=CHS

2.Chen 2021

LINK:https://kns.cnki.net/kcms2/article/abstract?v=yqeyU9EK6jR_XW5Z3mPDxkyme3NI4DoXhznzuWMqQmDji6RrU67zynGJ97EZJrLDmWYG5B7pv9e6TfxfRDraupGkVHZQ9070plbElSTDFNOcx1vR94oVQkXXzP0jGkDukRYC9DVIErU=&uniplatform=NZKPT&language=CHS

3. Cheng 2022

LINK: https://kns.cnki.net/kcms2/article/abstract?v=yqeyU9EK6jT1dAmV7rL-KIpLPmpheHbLyT5QSnjXfiXeuX68BMDP33lIhHTW5AoN_Ax8JOa7EnH06ZVvB52FhVxsg2I1_OVecwp7dma3zYV1jEvkS_TugnUCjfAnZR7iTQ1XjkalIyo=&uniplatform=NZKPT&language=CHS

4. Cui 2021

LINK: https://kns.cnki.net/kcms2/article/abstract?v=yqeyU9EK6jRX2Bo-wogWiT86QuBWDmzqStLSmOKGvbIBicLxqheF3Vwh3pv3eWHxGpcQA0ZIOwTG506uHe6sFLOF7K7AxeigNHTO8v0W5Qm2bKTFjq33aqLkCgzB9OJvbWfm0gMqUG8=&uniplatform=NZKPT&language=CHS

5. Gan 2020 doi：10.3969/j.issn.1671-038X.2020.12.10

LINK:https://kns.cnki.net/kcms2/article/abstract?v=yqeyU9EK6jRcsAtlmqq8ZFMv6NhdyrYXJ2X8

Attachment Submitted filename: Responses to Reviewers.docx

10.1371/journal.pone.0309144.r003
Decision Letter 1
Pullen Nicholas A. Academic Editor
© 2024 Nicholas A. Pullen
2024
Nicholas A. Pullen
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version1
9 Jul 2024

PONE-D-24-02154R1Efficacy and safety of berberine plus 5-ASA for ulcerative colitis : A systematic review and meta-analysisPLOS ONE

Dear Dr. Yang,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Thank you for your improved, revised submission. Substantial English language editing will still be required for me to endorse the paper further. Additionally, while you have figure titles, you still do not have figure legends. Please add these. I refer you to the PLOS page on this: https://journals.plos.org/plosone/s/figures. Specifically, from the page, under Figure legend tips: "Describe the key messages of a figure: provide a description of the figure that will allow readers to understand it without referring to the text."

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We look forward to receiving your revised manuscript.

Sincerely,

Nicholas A. Pullen, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

Thank you for your improved, revised submission. Substantial English language editing will still be required for me to endorse the paper further. Additionally, while you have figure titles, you still do not have figure legends. Please add these. I refer you to the PLOS page on this: https://journals.plos.org/plosone/s/figures. Specifically, from the page, under Figure legend tips: "Describe the key messages of a figure: provide a description of the figure that will allow readers to understand it without referring to the text."

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #1: No

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors have made tremendous improvements to enhance the transparency and reproducibility of their methods, which now reflect the rigor required for a systematic review.

The authors have also thoroughly addressed previous reviewer comments and have improved the clarity and organization of their manuscript.

While the clarity of the manuscript is greatly improved, there are still several grammatical errors throughout. These include punctuation errors, issues with spacing (or lack thereof) between characters, missing prepositions or conjunctions, and incorrect numbering of lists (e.g., under Primary Outcome Measures there are two #1’s). Once these minor issues are fixed, I believe the article will be ready for publication.

Some examples are below, although more instances can be found in the manuscript:

-Under the Inclusion Criteria section-- No need to use colons (the “:” symbol) after symptomatic relief, serological indicators, etc., because the lists that follow are encapsulated in parentheses.

-Under the Exclusion Criteria section-- Line 117, there is a period where there should be a semi-colon.

-Under the Primary Outcome Measures section-- Check the numbering. Both “clinical efficacy rate” and “complete remission” are labeled with the number 1.

-Character spacing throughout the manuscript -- There are many locations where there is no space between characters that should have spaces (e.g., between a period and a new word, or between a colon and a new word, etc.).

-In the Discussion, line 379-- Currently “effector cells, memory cells” --> “effector cells AND/OR memory cells.”

Reviewer #2: (No Response)

**********

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Reviewer #1: No

Reviewer #2: No

**********

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10.1371/journal.pone.0309144.r004
Author response to Decision Letter 1
Submission Version2
1 Aug 2024

Dear Editors and Reviewers:

We gratefully appreciate the editors and all reviewers for their time spent making positive and constructive comments. These comments are all valuable and helpful for revising and improving our manuscript entitled “Efficacy and safety of berberine plus 5-ASA for ulcerative colitis: A systematic review and meta-analysis” (PONE-D-24-02154).

We have made our utmost efforts to improve the manuscript in the following ways: (1) Correct grammatical errors in the manuscript;(2) Review the manuscript’s formatting and simplify complex sentences for better readability;(3) Revise the manuscript according to the reviewers' comments, such as changing “effector cells, memory cells” to “effector cells and/or memory cells. ”

These revisions will help enhance the overall quality of the manuscript. The reviewer comments are laid out below in italicized font and specific concerns have been numbered. We have studied comments carefully and have made corrections which we hope meet with approval. Our response is given in normal font and changes/additions to the manuscript are given in red.

Thank you and best regards.

Yours sincerely,

Lili Yang

Kaifeng Central Hospital

Responses to Reviewers

Comment 1: Under the Inclusion Criteria section-- No need to use colons (the “:” symbol) after symptomatic relief, serological indicators, etc., because the lists that follow are encapsulated in parentheses.

Response 1: Thank you for your careful and professional guidance. We have removed the ":" in that section as you suggested. (line 107-109 on page 5)

Comment 2: Under the Exclusion Criteria section-- Line 117, there is a period where there should be a semi-colon.

Response 2: Thank you for reading our paper so thoroughly. We have made the necessary revisions. (line 115 on page 5)

Comment 3: In the Discussion, line 379-- Currently “effector cells, memory cells” --> “effector cells AND/OR memory cells.”

Response 3:Thank you for your guidance. We have made the revisions according to your suggestions.

(line 388 on page 18)

Comment 4:Character spacing throughout the manuscript -- There are many locations where there is no space between characters that should have spaces (e.g., between a period and a new word, or between a colon and a new word, etc.).

Response 4: Thank you for your rigorous and specific review comments, which will enhance the readability of our manuscript. We also apologize for our errors. After a thorough review, we have corrected the incorrect character spacing in the manuscript. Here are a few examples of the revisions; more changes can be seen in the manuscript:

(1). We have added a space before the reference number in the citations. For example, changed “patients with active UC[17]” to “patients with active UC [17]”. (line 134 on page 6)

(2). Changed “(2)DAI” to “(2) DAI” (line 136 on page 6)

(3). Changed “Inflammatory cytokines: IL-6” to “Inflammatory cytokines: IL-6” (line 140 on page 6)

(4). Changed “BBR: 0.2g,tid” to “BBR: 0.2 g, tid”, “E:33.87±3.42” to “E: 33.87±3.42” (line 187 on page 10)

At the same time, we are also making revisions to other issues. Below are a few examples of the changes, with more modifications detailed in the manuscript.

(1). We have rephrased complex sentences. For instance, “Of particular interest is BBR, an efficacious alkaloid isolated from botanical sources such as Coptis chinensis and Phellodendron amurense, which was identified for its ability to relieve symptoms of abdominal discomfort and diarrhea within UC treatment paradigms” has been changed to “BBR, a potent alkaloid from Coptis chinensis and Phellodendron amurense, is noted for easing abdominal discomfort and diarrhea in UC treatment.” (line 62-63 on page 3)

(2). Standardized symbols: Changed “For the retrieval of literature, the search terms used were ‘ulcerative colitis’, ‘ulcerative’, ‘inflammatory bowel disease’, ‘BBR’, ‘BBR hydrochloride’, and ‘umbellate’ ‘randomized’ and ‘randomized controlled trial” has been changed to “For the retrieval of literature, the search terms used were ‘ulcerative colitis’, ‘ulcerative’, ‘inflammatory bowel disease’, ‘BBR’, ‘BBR hydrochloride’, ‘umbellate’, ‘randomized’, and ‘randomized controlled trial’.” (line 88-91 on page 4)

(3). Changed “in the treatment of UC” to “in treating UC”(line 121 on page 5)

(4). Changed “flow—chart” to “flowchart” (line 178 on page 8)

(5). Changed “w: Week” to “W: Week” (line 188 on page 10)

(6). Changed “I2” to “I2” (line 215 on page 11)

(7). Changed “（4）” to “(4) ” (line 256 on page 13)

(8). Changed “those with UC” to “UC patients” (line 353 on page 16)

(9). Changed “our” to “Our” (line 381 on page 17)

(10). Changed “Inflammatory” to “inflammatory” (line 382 on page 17)…

Comment 5: Under the Primary Outcome Measures section-- Check the numbering. Both “clinical efficacy rate” and “complete remission” are labeled with the number 1.

Response 5: Thank you for carefully reading our manuscript and providing valuable guidance. I believe we need explain the following: In the "Under the Primary Outcome Measures" section, (1) The evaluation of "clinical efficacy rate" includes three aspects, namely ①Complete remission; ②Effective treatment; and ③Ineffective treatment. Additionally, we have used different notations for "1" in the text. For example, we used (1) to annotate "clinical efficacy rate" and ① to annotate "complete remission". These two annotations are distinct. Based on the above situation, we have not made any changes here. Thank you again for your guidance. (line 120 on page 5)

Comment 6: Additionally, while you have figure titles, you still do not have figure legends. Please add these.

Response 6: Thank you for your guidance and comments. We have added the figure legends as requested and marked them in red in the manuscript. The details are as follows.

Fig 1. PRISMA flowchart of the study selection process. A total of 10 studies meeting the requirements were included. (line 178 on page 8)

Fig 2. Risk of bias summary. The quality of the included studies was evaluated. (line 209 on page 11)

Fig 3. Meta-analysis of Clinical effective rate. Berberine adjunctive therapy can improve the clinical effective rate. (line 218 on page 11)

Fig 4. Meta-analysis of Baron score. Berberine adjunctive therapy can reduce the Baron score. (line 229 on page 12)

Fig 5. Meta-analysis of DAI score. Berberine adjunctive therapy can reduce the DAI score. (line 238 on page 12)

Fig 6. Meta-analysis of clinical symptoms. Berberine adjunctive therapy can alleviate symptoms of abdominal pain, diarrhea, and hematochezia. (line 253 on page 13)

Fig 7. Meta-analysis of inflammatory cytokines. Berberine adjunctive therapy can reduce levels of IL-6, IL-8, and TNF-α and increase IL-10 levels. (line 279 on page 13)

Fig 8. Meta-analysis of CD4+ T cells, CD8+ T cells, CD4+/CD8+ ratio. Berberine adjunctive therapy can increase levels of CD4+ T cells and the CD4+/CD8+ T cell ratio, with no significant effect on CD8+ T cell levels. (line 297 on page 14)

Fig 9. Meta-analysis of adverse reactions. Berberine adjunctive therapy has no significant adverse reactions. (line 309 on page 15)

Fig 10. Clinical effective rate funnel chart. The clinical effectiveness rate showed no significant bias risk. (line 324 on page 15)

Attachment Submitted filename: Responses to Reviewers.docx

10.1371/journal.pone.0309144.r005
Decision Letter 2
Pullen Nicholas A. Academic Editor
© 2024 Nicholas A. Pullen
2024
Nicholas A. Pullen
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version2
7 Aug 2024

Efficacy and safety of berberine plus 5-ASA for ulcerative colitis : A systematic review and meta-analysis

PONE-D-24-02154R2

Dear Dr. Yang,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Sincerely,

Nicholas A. Pullen, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Thank you for your judicious attention to previous comments.

Reviewers' comments:

10.1371/journal.pone.0309144.r006
Acceptance letter
Pullen Nicholas A. Academic Editor
© 2024 Nicholas A. Pullen
2024
Nicholas A. Pullen
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
27 Aug 2024

PONE-D-24-02154R2

PLOS ONE

Dear Dr. Yang,

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team.

At this stage, our production department will prepare your paper for publication. This includes ensuring the following:

* All references, tables, and figures are properly cited

* All relevant supporting information is included in the manuscript submission,

* There are no issues that prevent the paper from being properly typeset

If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps.

Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

If we can help with anything else, please email us at customercare@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Nicholas A. Pullen

Academic Editor

PLOS ONE
==== Refs
References

1 Gros B , Kaplan G G . Ulcerative Colitis in Adults: A Review[J]. JAMA, 2023,330 (10 ):951–965.37698559
2 Le Berre C , Honap S , Peyrin-Biroulet L . Ulcerative colitis[J]. Lancet, 2023,402 (10401 ):571–584.37573077
3 Ng S C , Shi H Y , Hamidi N , et al . Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies[J]. Lancet, 2017,390 (10114 ):2769–2778.29050646
4 Singh S , Allegretti J R , Siddique S M , et al . AGA Technical Review on the Management of Moderate to Severe Ulcerative Colitis[J]. Gastroenterology, 2020,158 (5 ):1465–1496.31945351
5 Kucharzik T , Koletzko S , Kannengiesser K , et al . Ulcerative Colitis-Diagnostic and Therapeutic Algorithms[J]. Dtsch Arztebl Int, 2020,117 (33–34 ):564–574.33148393
6 Kobayashi T , Siegmund B , Le Berre C , et al . Ulcerative colitis[J]. Nat Rev Dis Primers, 2020,6 (1 ):74.32913180
7 Zhang B , Liu K , Yang H , et al . Gut Microbiota: The Potential Key Target of TCM’s Therapeutic Effect of Treating Different Diseases Using the Same Method-UC and T2DM as Examples[J]. Front Cell Infect Microbiol, 2022,12 :855075.35433500
8 Krugliak C N , Torres J , Rubin D T . What Does Disease Progression Look Like in Ulcerative Colitis, and How Might It Be Prevented?[J]. Gastroenterology, 2022,162 (5 ):1396–1408.35101421
9 Yang M , Yang C , Zhang Y , et al . An oral pH-activated "nano-bomb" carrier combined with berberine by regulating gene silencing and gut microbiota for site-specific treatment of ulcerative colitis[J]. Biomater Sci, 2022,10 (4 ):1053–1067.35037010
10 Wang X , Huang S , Zhang M , et al . Gegen Qinlian decoction activates AhR/IL-22 to repair intestinal barrier by modulating gut microbiota-related tryptophan metabolism in ulcerative colitis mice[J]. J Ethnopharmacol, 2023,302 (Pt B ):115919.36356716
11 Hu S , Wei P , Li W , et al . Pharmacological effects of berberine on models of ulcerative colitis: A meta-analysis and systematic review of animal studies[J]. Front Pharmacol, 2022,13 :937029.36147325
12 Xu L , Zhang Y , Xue X , et al . A Phase I Trial of Berberine in Chinese with Ulcerative Colitis[J]. Cancer Prev Res (Phila), 2020,13 (1 ):117–126.
13 Rethlefsen M L , Page M J . PRISMA 2020 and PRISMA-S: common questions on tracking records and the flow diagram[J]. J Med Libr Assoc, 2022,110 (2 ):253–257.35440907
14 Wu Kaichun J L Z R . Consensus opinions on the diagnosis and treatment of inflammatory bowel disease(2018,Bei jing)[J]. Chinese Journal of Digestion, 2018,38 (05 ):292–311.
15 Zhang S , Zhao L , Shen H , et al . International clinical practice guideline on the use of traditional Chinese medicine for ulcerative colitis by Board of Specialty Committee of Digestive System Disease of World Federation of Chinese Medicine Societies (2023)[J]. Phytother Res, 2024,38 (2 ):970–999.38112572
16 Li Junxiang C J. Consensus opinions on the integrated diagnosis and treatment of ulcerative colitis in traditional Chinese medicine and Western medicine (2017)[J]. Chinese Journal of Integrated Traditional Chinese and Western Medicine in Gastroenterology, 2018,26 (02 ):105–111.
17 BARON JH , CONNELL A M , LENNARD-JONES J E . VARIATION BETWEEN OBSERVERS IN DESCRIBING MUCOSAL APPEARANCES IN PROCTOCOLITIS[J]. Br Med J, 1964,1 (5375 ):89–92.14075156
18 Mohammed V N , Samaan M , Mosli M H , et al . Endoscopic scoring indices for evaluation of disease activity in ulcerative colitis[J]. Cochrane Database Syst Rev, 2018,1 (1 ):CD11450.
19 Pabla B S , Schwartz D A . Assessing Severity of Disease in Patients with Ulcerative Colitis[J]. Gastroenterol Clin North Am, 2020,49 (4 ):671–688.33121688
20 Ungaro R , Mehandru S , Allen P B , et al . Ulcerative colitis[J]. Lancet, 2017,389 (10080 ):1756–1770.27914657
21 Yao D , Dong M , Dai C , et al . Inflammation and Inflammatory Cytokine Contribute to the Initiation and Development of Ulcerative Colitis and Its Associated Cancer[J]. Inflamm Bowel Dis, 2019,25 (10 ):1595–1602.31287863
22 Smids C , Horjus T H C , Drylewicz J , et al . Intestinal T Cell Profiling in Inflammatory Bowel Disease: Linking T Cell Subsets to Disease Activity and Disease Course[J]. J Crohns Colitis, 2018,12 (4 ):465–475.29211912
23 Al A F , Lin L . Empirical assessment of prediction intervals in Cochrane meta-analyses[J]. Eur J Clin Invest, 2021,51 (7 ):e13524.33595098
24 Chen D , Z W . The effects of berberine hydrochloride tablets as an adjuvant treatment for distal ulcerative colitis and their impact on serum inflammatory factor levels in patients[J]. Chin J Mod Drug Appl, 2020,14 (10 ):135–137. doi: 10.14164/j.cnki.cn11-5581/r.2020.10.063
25 Chen Y , J J Z J . Effect of mesalazine combined with berberine on the levels of TNF -o.IL-17 and IL-23 in patients with distal ulcerative colitis[J]. China Modern Doctor, 2021,59 (22 ):46–49.
26 Cheng H. Berberine Hydrochloride Combined with Salazosulfapyridine in the Treatment of Ulcerative Colitis; A Clinical Study[J]. Chinese Journal of Colorectal and Anal Diseases, 2022,42 (2 ):55–57.
27 Cui W , J C Y G . Clinical study on Berberine Hydrochloride Tablets combined with sulfasalazine in treatment of ulcerative colitis[J]. Drugs & Clinic, 2021,36 (1 ):85–89.
28 Gan J , F H Z Z . Effects of chlorhexidine hydrochloride on intestinal flora and immunestatus in patients with ulcerative colitis[J]. Chin J Integr Trad West Med Dig, 2020,28 (12 ):949–953. doi: 10.3969/j.issn.1671-038X.2020.12.10
29 Wang P. Salt of berberine combined with mesalazine for the treatment of ulcerative colitis: an observational study on the therapeutic effects[J]. Clinical Medical Engineering, 2020,27 (6 ):771–772. doi: 10.3969/j.issn.1674-4659.2020.06.0771
30 Wang Y , X L . Evaluation of the therapeutic effects of berberine hydrochloride tablets combined with mesalazine in the treatment of patients with distal ulcerative colitis[J]. HENAN MEDICAL RESEARCH, 2021,30 (23 ):4371–4373. doi: 10.3969/j.issn.1004-437X.2021.23.044
31 Wei L. The therapeutic efficacy of berberine combined with mesalazine and its impact on inflammatory factors in patients with distal ulcerative colitis[J]. Proceeding of Clinical Medicine, 2019,28 (7 ):506–508. doi: 10.16047/j.cnki.cn14-1300/r.2019.07.009
32 Xu Q ,J H J C . Effects of berberine combined with mesalazine on the treatment of distal ulcerative colitis and its impact on inflammatory factors in patients[J]. Modern Digestion&lntervention, 2020,25 (8 ):541.
33 Zhu T , W Y K H . Clinical study on Berberine Hydrochloride Tablets combined with mesalazine intreatment of distal ulcerative colitis[J]. Drugs & Clinic, 2018,33 (12 ):3183–3186.
34 Long Y , Xia C , Xu L , et al . The Imbalance of Circulating Follicular Helper T Cells and Follicular Regulatory T Cells Is Associated With Disease Activity in Patients With Ulcerative Colitis[J]. Front Immunol, 2020,11 :104.32117258
35 Feuerstein J D , Moss A C , Farraye F A . Ulcerative Colitis[J]. Mayo Clin Proc, 2019,94 (7 ):1357–1373.31272578
36 Zhu C , Li K , Peng X X , et al . Berberine a traditional Chinese drug repurposing: Its actions in inflammation-associated ulcerative colitis and cancer therapy[J]. Front Immunol, 2022,13 :1083788.36561763
37 Xiong X , Cheng Z , Wu F , et al . Berberine in the treatment of ulcerative colitis: A possible pathway through Tuft cells[J]. Biomed Pharmacother, 2021,134 :111129.33348308
38 Xiong K , Deng J , Yue T , et al . Berberine promotes M2 macrophage polarisation through the IL-4-STAT6 signalling pathway in ulcerative colitis treatment[J]. Heliyon, 2023,9 (3 ):e14176.36923882
39 Luo M , Zhao F , Cheng H , et al . Macrophage polarization: an important role in inflammatory diseases[J]. Front Immunol, 2024,15 :1352946.38660308
40 Li X , Xu S , Zhang Y , et al . Berberine Depresses Inflammation and Adjusts Smooth Muscle to Ameliorate Ulcerative Colitis of Cats by Regulating Gut Microbiota[J]. Microbiol Spectr, 2022,10 (6 ):e320722.
41 Neurath M F , Vieth M . Different levels of healing in inflammatory bowel diseases: mucosal, histological, transmural, barrier and complete healing[J]. Gut, 2023,72 (11 ):2164–2183.37640443
42 Radeke H H , Stein J , Van Assche G , et al . A Multicentre, Double-Blind, Placebo-Controlled, Parallel-Group Study to Evaluate the Efficacy, Safety, and Tolerability of the S1P Receptor Agonist KRP203 in Patients with Moderately Active Refractory Ulcerative Colitis[J]. Inflamm Intest Dis, 2020,5 (4 ):180–190.33313070
43 Nakase H , Sato N , Mizuno N , et al . The influence of cytokines on the complex pathology of ulcerative colitis[J]. Autoimmun Rev, 2022,21 (3 ):103017.34902606
44 Salah N , Dubuquoy L , Carpentier R , et al . Starch nanoparticles improve curcumin-induced production of anti-inflammatory cytokines in intestinal epithelial cells[J]. Int J Pharm X , 2022,4 :100114.
45 Laurindo L F , Santos A , Carvalho A , et al . Phytochemicals and Regulation of NF-kB in Inflammatory Bowel Diseases: An Overview of In Vitro and In Vivo Effects[J]. Metabolites, 2023,13 (1 ).
46 Wang Y , Shao Z , Song C , et al . Clinopodium chinense Kuntze ameliorates dextran sulfate sodium-induced ulcerative colitis in mice by reducing systematic inflammation and regulating metabolism[J]. J Ethnopharmacol, 2023,309 :116330.36868438
47 Sun L , Su Y , Jiao A , et al . T cells in health and disease[J]. Signal Transduct Target Ther, 2023,8 (1 ):235.37332039
48 Gomez-Bris R , Saez A , Herrero-Fernandez B , et al . CD4 T-Cell Subsets and the Pathophysiology of Inflammatory Bowel Disease[J]. Int J Mol Sci, 2023,24 (3 ).
49 Giuffrida P , Di Sabatino A . Targeting T cells in inflammatory bowel disease[J]. Pharmacol Res, 2020,159 :105040.32585338
50 Zebley C C , Gottschalk S , Youngblood B . Rewriting History: Epigenetic Reprogramming of CD8(+) T Cell Differentiation to Enhance Immunotherapy[J]. Trends Immunol, 2020,41 (8 ):665–675.32624330
51 Bolivar-Wagers S , Larson J H , Jin S , et al . Cytolytic CD4(+) and CD8(+) Regulatory T-Cells and Implications for Developing Immunotherapies to Combat Graft-Versus-Host Disease[J]. Front Immunol, 2022,13 :864748.35493508
52 Saez A , Herrero-Fernandez B , Gomez-Bris R , et al . Pathophysiology of Inflammatory Bowel Disease: Innate Immune System[J]. Int J Mol Sci, 2023,24 (2 ).
53 Tong L , Hao H , Zhang Z , et al . Milk-derived extracellular vesicles alleviate ulcerative colitis by regulating the gut immunity and reshaping the gut microbiota[J]. Theranostics, 2021,11 (17 ):8570–8586.34373759
54 Zhong Y , Xiao Q , Kang Z , et al . Astragalus polysaccharide alleviates ulcerative colitis by regulating the balance of Tfh/Treg cells[J]. Int Immunopharmacol, 2022,111 :109108.35926271
55 Tubau-Juni N , Hontecillas R , Leber A J , et al . Treating Autoimmune Diseases With LANCL2 Therapeutics: A Novel Immunoregulatory Mechanism for Patients With Ulcerative Colitis and Crohn’s Disease[J]. Inflamm Bowel Dis, 2024,30 (4 ):671–680.s37934790
