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 <i>Lactobacillus rhamnosus</i> and <i>Lactobacillus casei</i> 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 <i>p</i> < 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; <i>p</i> = 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 <i>L. rhamnosus</i> as a potential adjunctive nutritional strategy for dyslipidemia management.