Systematic review finds gut microbiota drugs reduce liver enzymes in MASLD patients compared to placebo.

OBJECTIVE: Currently, effective drugs for metabolic dysfunction-associated steatotic liver disease (MASLD) are limited, with treatment primarily focusing on diet and exercise. Recent studies suggest that gut microbiota-regulating drugs may offer therapeutic benefits. Therefore, our aim is to evaluate the efficacy of these medications in MASLD patients. METHODS: This systematic review and network meta-analysis involved a search of PubMed, Web of Science, Embase, Cochrane Library, and ClinicalTrials.gov for randomized controlled trials (RCTs) published from January 1, 2012, to January 28, 2026. The intervention measures encompassed probiotics, prebiotics, synbiotics, antibiotics, postbiotics, and a combination of antibiotics and gut microbiota-regulating drugs. The control group received a placebo or usual care. The risk of bias in the included research was evaluated utilizing the revised Cochrane risk of bias tool for randomised trials. The confidence of evidence will be evaluated through the CINeMA (Confidence in Network Meta-Analysis) web application. Liver enzymes and hepatic steatosis were taken as the primary outcome and were analyzed by random-effects, Bayesian network meta-analyses. A two stage network meta-analysis harnessing the surface under the cumulative ranking curve (SUCRA) was performed for assessing the comparative efficacy of medications classes and particular gut microbiota-regulating drugs. The study was registered on PROSPERO: CRD42024606333. RESULTS: A total of 27 studies comprising 1,511 participants were included in this meta-analysis. Relative to placebo, reductions in alanine aminotransferase (ALT) levels were observed with probiotics (Mean Difference (MD): -7.51, 95% credible intervals (CI) [-12.36 to -2.66]), prebiotics (MD: -13.64, 95% CI [-27.07 to -0.22]) and antibiotics (MD: -24.30, 95% CI [-47.02 to -1.58]). Probiotics (MD: -6.42, 95% CI [-11.91 to -0.92]) and synbiotics (MD: -13.13, 95% CI [-20.82 to -5.45]) were both associated with a reduction in aspartate aminotransferase (AST) levels compared to placebo. Declines in gamma-glutamyl transferase (GGT) levels (MD: -12.40, 95% CI [-23.13 to -1.68]) were observed with synbiotics compared to the placebo. Additionally, synbiotics significantly reduced controlled attenuation parameter (CAP) levels compared with placebo (MD: -45.69, 95% CI [-56.39 to -34.99]). However, no statistically significant differences were observed between probiotics and synbiotics with respect to lipid markers total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), or inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). CONCLUSIONS: Probiotics and synbiotics significantly improve liver enzymes and hepatic steatosis in patients with MASLD.