Improving Lipid Profiles Through Lactobacillus rhamnosus Supplementation in Dyslipidemic Animal Models: A Systematic Review and Meta-Analysis

Dyslipidemia, characterized by elevated triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels, is a major cardiovascular risk factor. However, evidence regarding the lipid-modulating efficacy of Lactobacillus rhamnosus and Lactobacillus casei remains limited. This systematic review and meta-analysis (PROSPERO: CRD420251153531) evaluated their lipid-modulating effects in preclinical dyslipidemia models. A comprehensive search of four databases up to July 2025 identified 12 studies. Risk of bias was assessed using the SYRCLE tool. Random-effects meta-analyses were conducted to estimate standardized mean differences (SMDs) and 95% confidence intervals (CIs): probiotics significantly reduced TG (SMD: −1.38; 95% CI: from −1.92 to −0.84), TC (SMD: −0.85; 95% CI: from −1.20 to −0.42), and LDL-C levels (SMD: −1.59; 95% CI: from −2.16 to −1.02; all p < 0.001). In contrast, no significant effect was observed on high-density lipoprotein cholesterol levels (SMD: 0.18; 95% CI: from −0.35 to 0.72; p = 0.5044). Heterogeneity was moderate to substantial (I2 = 36–51%), although publication bias for TC and LDL-C suggests cautious interpretation of results. The lipid-lowering effects are likely mediated by bile salt hydrolase activity and short-chain fatty acid production along the gut–liver axis. These findings support L. rhamnosus as a potential adjunctive nutritional strategy for dyslipidemia management.