A meta-analysis of berberine hydrochloride in adjuvant treatment of ulcerative colitis and its influence on inflammatory factors

JI Shuang-shuang, LIU Zi-hao, WANG Meng-yuan, HONG Yan-qiu, YIN Yu-zhang, ZHANG Shu-xin

1. Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing 100700, China

Keywords:Berberine hydrochloride；Ulcerative colitis；Inflammatory factors Meta-analysis

ABSTRACT Objective: To evaluate the clinical efficacy of berberine hydrochloride in the treatment of ulcerative colitis and its influence on inflammatory factors. Methods: We searched VIP Chinese Journal Database (VIP),China Biomedical Literature Database (CBM), Wanfang Data, China Knowledge Network (CNKI), and searched English databases including:PubMed, Embase, Web of Science, and Cochrane Library for randomized controlled studies of berberine hydrochloride in the treatment of ulcerative colitis. The retrieval time was from the establishment of the database to April 28, 2021.After the quality evaluation of the selected literature, the RevMan5.3 software was used for statistical analysis. Results: Eight studies were included, involving 658 patients with ulcerative colitis. Meta analysis showed that the effective rate of the treatment group was higher than that of the control group, and the difference was statistically significant [OR=6.41,95%CI(3.25,12.65),Z=5.36, P<0.000 01]; IL-6 [MD=-13.64,95%CI(-14.88, -12.41),Z=3.99, P<0.000 01],IL-8 [MD=-13.41,95%CI(-15.11,-11.71),Z=15.46, P<0.000 01], tumor necrosis factor [MD=-5.62,95%CI(-8.35,-2.89), Z=4.03,P<0.000 1], and disease activity index [MD=-2.34,95%CI(-2.55,-2.14), Z=22.37, P<0.00 0 01] in the treatment group were lower than the control group, the difference was statistically significant; IL-10 [MD=6.49,95%CI(5.64,7.35),Z=14.86, P<0.000 01] in the treatment group was higher than the control group, and the difference was statistically significant; abdominal pain relief time [MD=-3.41,95%CI(-4.02,-2.79), Z=10.84, P<0.000 01], diarrhea relief time [MD=-2.5,95%CI(-2.86,-2.15),Z=13.87, P<0.000 01], pus and blood stool remission time [MD=-2.44,95%CI(-2.87,-2.00).Z=10.87, P<0.000 01] in the treatment group were shorter than the control group, and the difference was statistically significant. Conclusion:Berberine hydrochloride can assist in the treatment of ulcerative colitis by reducing the level of inflammatory factors.?Corresponding author:ZHANG Shu-xin, Ph.D, Professer, Doctoral Supervisor,E-mail:13661027611@126.com.

1. Introduction

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disease of the colon [1]. In recent years, the incidence and prevalence of UC in my country have shown a rapid upward trend, and it has become a common clinical disease [2]. The etiology is currently unclear [3], and the pathogenesis is more complex, involving immune disorders, genetic factors, environmental factors and intestinal flora disorders and other factors [4]. 5-Aminosalicylic acid (5-ASA) is the first-line treatment for mild to moderate UC [5], but existing studies have shown that the overall response rate of UC patients to 5-ASA is only 70%-80%, and the recurrence rate The difference is large,and the drug needs to be administered multiple times a day, which often leads to reduced patient compliance [5]. Therefore, it is very important to seek other ways to improve the therapeutic effect of 5-ASA [6].

Berberine (BBR) is an isoquinoline alkaloid [7], derived from a plant of the Berberaceae family, and is the main component of the Chinese herbal medicine Coptis[8]. BBR can inhibit the transcription of pro-inflammatory genes such as IL-1β, TNF-α,IL-6, and monocyte chemoattractant protein 1 (MCP-1) [9], and has a positive effect on prostaglandin E2 (PGE2) and cyclooxygenase.The expression of 2(COX-2) has an inhibitory effect [10]. A number of clinical and animal experiments have confirmed that berberine hydrochloride has a therapeutic effect on UC [11,12]. Therefore, this study conducted a systematic evaluation of the effectiveness of berberine hydrochloride in the treatment of UC and its influence on inflammatory factors in patients with UC by searching domestic and foreign literature databases, searching for relevant literature, in order to provide evidence-based treatment for berberine in the treatment of UC. Medical evidence.

2. Materials and methods

2.1 Literature inclusion and exclusion criteria

2.1.1 Inclusion criteria

(1) Research type: Randomized controlled trials (RCTs). (2)Research object: Age> 18 years old, diagnosed as ulcerative colitis.(3) Intervention measures: The control group was treated with aminosalicylic acid orally, and the treatment group was treated with berberine hydrochloride orally. The treatment group and the control group had the same course of treatment. (4) Outcome indicators:clinical effective rate; inflammatory factors include: interleukin 6(IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), tumor necrosis factor-α (TNF-α); abdominal pain Remission time; diarrhea remission time; pus and blood stool remission time; disease activity index (DAI). At least one of the above indicators is included.

2.1.2 Exclusion criteria

(1) Non-oral administration of berberine hydrochloride;(2) Control group did not use aminosalicylic acid drugs; (3)Repeated publications; (4) Documents with no data extraction; (5)Unpublished publications Dissertation.

2.2 Search strategy

Computer-searched Chinese databases include CBM, Wanfang Data, CNKI, VIP; English databases include PubMed, Embase, Web of Science, Cochrane Library, and the search time is limited to the establishment of the database until April 28, 2021. Chinese search for "berberine hydrochloride", "berberine", "berberine", "ulcerative colitis", "ulceration" and other related synonyms; English search for "Berberine hydrochloride" "Berberine" "Umbellatine" "Colitis,Ulcerative" "Idiopathic" Proctocolitis", "Ulcerative Colitis", "Colitis Gravis", "Inflammatory Bowel Disease, Ulcerative Colitis Type" and other subject words and free words.

2.3 Literature screening and data extraction

Two researchers use Endnote to independently carry out literature screening and data extraction. When there is a disagreement, they will discuss with the third researcher and make a joint decision.

2.4 Quality evaluation of the included literature

The risk of bias (ROB) risk assessment tool in the Cochrane Handbook was used to evaluate the quality of the included literature.

2.5 Statistical methods

RevMan 5.3 software for meta-analysis. Count data are statistical effect size in Odds ratios (OR), and continuous variables are expressed in mean difference (MD). Provide a 95% confidence interval (CI). Higgins I2 is used to assess heterogeneity. When the heterogeneity test result is not statistically significant (P>0.05,I2<50%), a fixed-effects model is used for meta-analysis. If I2≥50%, a heterogeneity test is required Find out the reasons for the heterogeneity. After sensitivity analysis or subgroup analysis, if the heterogeneity remains 50% or more, only the result description will be performed. The results were statistically significant with P<0.05.

3. Results

3.1 Search results

According to the above retrieval method, 1103 documents were initially retrieved, of which 535 were duplicate documents.415 articles on reviews, experiences, reviews, conferences, and experiments were preliminarily screened out, and 141 articles with inconsistent content were eliminated after reading the titles and abstracts of the articles. For the remaining 12 articles, the following articles were deleted after reading the full text: 2 non-randomized controlled trials, 1 article without aminosalicylic acid intervention in the treatment group and control group, and 1 dissertation. Finally, 8 articles were included for analysis. The screening process is shown in Figure 1.

3.2 Basic characteristics of the included literature

Eight RCT studies were included, involving a total of 658 patients with UC. Its basic characteristics are shown in Table 1.

3.3 Quality evaluation results

Among the 8 included RCTs, 3 studies [14, 15, 19] used random number table method to generate random sequence, which was evaluated as low risk of bias; 3 studies [16, 18, 20] only mentioned"random "The two characters did not describe the specific random sequence generation method, and the risk of bias is not clear. The remaining 2 studies, one study [13] were grouped by the order of visits, and the other study [17] was grouped by the treatment plan,which was evaluated as high risk. In 8 studies, the implementation of allocation concealment and the implementation of blinding were not reported, so the risk of bias is not yet clear; in the incomplete outcome evaluation, Zhu Tianyu [20] lacked a complete adverse reaction rate. Because of the high risk of deviation, the enrollment data of the remaining 7 literatures are consistent with the research results, which is low-risk bias; in the evaluation of the selective outcome report, the outcome mentioned in the reporting methodology is compared with the outcome of the reported result.The evaluation is low risk of bias; the other biases of the 8 studies are unclear. Due to the incomplete report of the evaluation items such as the random sequence generation method, the implementation of allocation concealment, and the blinding method of subjects,researchers, and outcome evaluators, the overall quality of the included literature was low(Figure 2-3).

3.4 Meta analysis results

3.4.1 Analysis of clinical effectiveness

A total of 6 articles [13, 14, 16, 18,19,20] documented the clinical effectiveness, involving a total of 484 UC patients. Meta analysis suggests that the treatment group has a higher clinical effective rate than the control group, and the difference is statistically significant[OR=6.41, 95%CI (3.25, 12.65), Z=5.36, P<0.000 01](Fig.4).

Tab 1 Document characteristics table

3.4.2 IL-6 levelsA total of 5 documents [14, 15, 17, 19, 20] recorded serum IL-6 levels.After heterogeneity test, I2=97%, P<0.000 01. After excluding the documents one by one, Wang Pengli [16] was found to be different Qualitative source. After excluding the literature, I2=0%, P=1.00.Meta analysis indicated that the serum IL-6 of the treatment group was lower than that of the control group, and the difference was statistically significant [MD=-13.64, 95%CI (-14.88,-12.41), Z=3.99,P<0.000 01] (Figure 5).

3.4.3 IL-8 levelsA total of 5 literatures [14, 15, 17, 19, 20] recorded serum IL-8 levels,and the heterogeneity test indicated that I2=73%, P=0.005, and the literature was excluded one by one and found that Dangerous Liuliu [18] was heterogeneous Sexual source, I2=0%, P=1.00 after elimination. Meta analysis indicated that the serum IL-8 level of the treatment group was lower than that of the control group. The difference is statistically significant [MD=-13.41, 95%CI (-15.11,-11.71), Z=15.46, P<0.000 01] (Figure 6).

3.4.4 IL-10 levelsA total of 3 literatures [14, 17, 20] recorded the serum IL-10 level,with I2=0% and P=0.97 after the heterogeneity test. Meta-analysis indicated that the serum IL-10 of the treatment group was higher than that of the control group, and the difference was statistically significant [MD=6.49,95%CI(5.64,7.35),Z=14.86,P<0.000 01](Figure7).

3.4.5 TNF-α levelA total of 6 literatures [14,15,16,17,19,20] recorded serum TNF-α levels,and the heterogeneity test I2=97%, P<0.000 01, after excluding the literature one by one, the heterogeneity did not change significantly, Suggesting that the result is robust. Meta analysis indicated that the serum TNF-α level of the treatment group was lower than that of the control group. The difference is statistically significant [MD=-5.62,95%CI(-8.35,-2.89), Z=4.03, P<0.000 1] (Fig 8).

3.4.6 DAI score

A total of 3 documents [13, 17, 19] recorded DAI scores before and after treatment. The heterogeneity test indicated that I2=98%,P<0.000 01. After excluding the documents one by one, Cui Wenjuan [13] was found to be the source of heterogeneity. I2=0%,P=0.79. Meta-analysis indicated that the DAI score of the treatment group was lower than that of the control group. The difference is statistically significant [MD=-2.34, 95%CI (-2.55, -2.14), Z=22.37,P<0.000 01] (Figure 9).

3.4.7 Relief of abdominal pain, relief of diarrhea, relief of pus and blood in stool

Three documents [17, 18, 20] recorded the disappearance of abdominal pain, diarrhea, and pus and blood in the stool, involving 250 patients, including 125 cases in the treatment group and 125 cases in the control group.

In the remission time of abdominal pain, the heterogeneity test I2=0%, P=0.70. The meta-analysis indicated that the treatment group had a shorter time to relieve abdominal pain than the control group.The difference is statistically significant [MD=-3.41, 95%CI (-4.02,-2.79), Z=10.84, P<0.000 01] (Figure10).

In the remission time of diarrhea, the heterogeneity test I2=0%,P=0.42, meta-analysis indicated that the treatment group had a shorter remission time of abdominal pain than the control group, and the difference was statistically significant [MD=-2.5, 95%CI(-2.86,-2.15),Z=13.87,P<0.00001] (Figure11).

In the remission time of pus and blood in the stool, the heterogeneity test indicated that I2=0%, P=0.55, and the metaanalysis indicated that the treatment group had a shorter recovery time than the control pus and blood in the stool, and the difference was statistically significant [MD=-2.44,95%CI( -2.87,-2.00),Z=10.87, P<0.000 01] (Figure12).

3.4.8 Evaluation of adverse reactions

Three studies [14, 16, 20] observed the occurrence of adverse reactions, among which Zhu Tianyu [20] did not fully report the incidence of adverse reactions, and the adverse reactions of the two groups in the study of Chen Dan [14] and Wang Pengli [16] There was no statistically significant difference in incidence.

3.5 Publication offset

Fewer than 10 articles were included in this study, so the funnel chart was not used to assess publication bias.

4. Discussion

4.1 Theoretical basis for BBR treatment of UC

UC is a type of chronic inflammatory disease, and its incidence is rising worldwide [21]. Young and middle-aged people are the main targets [21]. The clinical manifestations vary in severity and are prone to recurrent episodes [22]. The typical manifestations are diarrhea,abdominal pain, mucus, pus, and blood in the stool [22]. Up to 18%of UC patients are accompanied by chronic active disease, and 30%of them require colectomy within 10 years [23].

The pathogenesis of UC is currently unclear, and many factors may be involved [21]. Among them, the immune response disorder plays a central role in the pathogenesis of UC [24]. Pro-inflammatory mediators such as IL-1, IL-6, TNF-α, cyclooxygenase (COX)-2,prostaglandins and leukotrienes can be produced in large quantities due to the activation of the immune system [25], in addition, signal transduction The disorder of the mechanism is also closely related to the occurrence of UC [26]. IL-6, IL-8, TNF-α, etc. are a class of pro-inflammatory cytokines. IL-6 can regulate the adaptive immune response in IBD [25], and IL-8 has a powerful pro-inflammatory effect and can extensively regulate inflammatory cells [27]. The production of pro-inflammatory interleukins can lead to an increase in TNF-α [28]. TNF-α stimulates NF-κB signal transduction and can promote the further release of other inflammatory mediators[29], so it is often used to evaluate the body's inflammatory response. An indicator of severity. The activation of anti-inflammatory cytokines such as IL-10 can limit the inflammatory response and reduce the levels of pro-inflammatory cytokines such as TNF-α and interleukins[29, 30]. Related studies have shown that the loss of IL-10 receptor expression will promote the development of colitis [30]. Two classic signaling pathways related to the development of inflammation include mitogen-activated protein kinase (MAPK) and NF-κB pathway [28]. NF-κB is an important transcription factor downstream of the MAPK signaling pathway, which can induce the synthesis of inflammatory cytokines (such as IL-1, IL-6, etc.) and the expression of pro-inflammatory enzymes (such as COX-2, etc.), and the activation of this signaling pathway It is an important mechanism of the pathogenesis of UC[31,32].

Ulcerative colitis belongs to the categories of traditional Chinese medicine such as "long dysentery", "intestinal dysentery", and"rest dysentery" [2, 33]. Traditional Chinese medicine has a long history of preventing and treating UC. Traditional Chinese herbal medicine has multiple targets, multiple pathways, multiple effects,and improves the body environment. Other advantages [34, 35],however, oral Chinese medicine still has some shortcomings, such as poor water solubility, poor gastrointestinal stability, and poor oral bioavailability. The extraction of active ingredients of traditional Chinese medicine can avoid the above problems. For example, the currently known active ingredients such as alkaloids, quinones,terpenoids and polyphenols show the therapeutic potential of UC [34].Berberine exhibits strong biological activities in anti-inflammatory,immune regulation, anti-tumor, and hypoglycemic aspects [36].Studies have confirmed that BBR does have a therapeutic effect on UC, and its mechanism may be related to the regulation of intestinal flora, defense of the intestinal barrier, regulation of immune response and reduction of oxidative stress [12]. An animal experiment by Liao et al. [37] showed that berberine can enrich the probiotics in the intestine and reduce the potential pathogenic bacteria in the intestine.At the same time, it can regulate the metabolism of UC rats, such as restoring the digestion and absorption of carbohydrates, promoting glycolysis/gluconeogenesis and amino acid metabolism, thereby improving the colon injury of UC rats and restoring dysfunctional functions. At present, it is known that the mechanism of 5-ASA drugs in the treatment of UC is mainly by inhibiting the cyclooxygenase and lipoxygenase pathways, reducing the production of PGE2 and leukotrienes, and inhibiting the expression of inflammatory factors produced after the activation of the NF-κB signaling pathway. [38].Yan et al. [6] proposed that BBR can also attenuate the expression of COX-2 and reduce the cumulative effect of inflammatory cytokines.This study shows that BBR combined with 5-ASA drugs can enhance the therapeutic effect of 5-ASA on UC, thereby Reducing the dosage of 5-ASA increases patient compliance during long-term administration. BBR also has varying degrees of inhibitory effects on the levels of pro-inflammatory cytokines in UC patients [31], and its anti-inflammatory activity may mainly depend on the inhibition of the NF-κB pathway [39]. In addition, the mechanism of berberine in the treatment of UC may also involve the inhibition of JAK-STAT,PI3K-AKT, MAPK and other signaling pathways [40].

4.2 Clinical effectiveness and influence on inflammatory factors

In this study, based on the Cochrane system evaluation principle,berberine hydrochloride adjuvant treatment of ulcerative colitis and the effect of inflammatory factors were systematically evaluated.Meta-analysis showed that the clinical effectiveness of berberine hydrochloride combined with aminosalicylic acid drugs, DAI score,abdominal pain relief time, diarrhea relief time, and pus and blood remission time were better than aminosalicylic acid therapy alone.And compared with the control group, berberine hydrochloride combined with aminosalicylic acid drugs can significantly reduce the expression of pro-inflammatory cytokines (IL-6, IL-8, TNF-α) in the serum of UC patients, and increase the resistance of UC patients.Expression of inflammatory cytokine (IL-10).

4.3 Limitations of this study

(1) Only 8 articles were included in this study, and publication bias was not evaluated. (2) Only 3 studies mentioned specific and appropriate random allocation methods, and none of the studies mentioned blinding and allocation concealment, which may be one of the sources of bias; (3) The population involved in the included literature is all from China The range of people and ethnicity is not comprehensive, which reduces the strength of the evidence of the systematic review and affects the extrapolation of the analysis results; (4) The included literature lacks long-term follow-up and insufficient safety reports, so the efficacy, safety, and patient The quality of life and long-term efficacy need to be further verified.

5. Conclusion

In this study, a meta-analysis of 8 included literatures showed that berberine hydrochloride combined with aminosalicylic acid drugs can further improve the clinical effectiveness of UC patients,shorten the time to relieve abdominal pain, diarrhea, pus and blood in the stool, and reduce the DAI score. Inhibit the production of proinflammatory cytokines and increase the level of anti-inflammatory cytokines. However, the quality of the literature included in this study is low and the number is small, so it is still necessary to design more rigorous large-sample, multi-center, high-quality evidencebased studies to further verify some conclusions.

Author's contribution Ji Shuangshuang selects the topic of the article, and Zhang Shuxin conducts quality control and research guidance on the research.Ji Shuangshuang, Liu Zihao, and Wang Mengyuan conducted document screening and data extraction; Hong Yanqiu checked the data; Ji Shuangshuang made the chart, and Yin Yuzhang was responsible for the modification of the chart. Ji Shuangshuang wrote the paper, and Zhang Shuxin revised the paper. This article has no conflict of interest.