Effects of berberine and barberry on selected inflammatory biomarkers in adults: A systematic review and dose–response meta‐analysis of randomized clinical trials

The previous meta-analysis showed an advantageous effect of berberine supplementation on interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and serum C-reactive protein (CRP) concentrations; however, it is unknown the dosage that this component influences inflammatory biomarkers. A comprehensive search was done in Scopus, PubMed, and Web of Science until September 2022 to find randomized controlled trials (RCT) that assessed the effects of berberine/barberry on IL-6, TNF-α, and CRP in adults but not trials without a control group. Studies bias was assessed using RoB 2. A random-effects model was performed to calculate the weighted mean difference (WMD). A dose-dependent effect was calculated. Eighteen clinical trials with 1600 participants were included in the current meta-analysis. These interventions significantly mitigate IL-6 levels (-1.18 pg/mL), TNF-α levels (-3.72 pg/mL), and CRP levels (-1.33 mg/L). In addition, the non-linear analysis showed a significant lowering effect of berberine/barberry on IL-6 and TNF-α levels in doses <1000 mg/day and less than 5 weeks of intervention. There are limitations to our findings, including low-quality studies and significant heterogeneity. These interventions might be considered adjunct therapy to managing inflammation status. However, more investigation and high-quality evidence must be conducted to obtain more comprehensive and generalizable results.