Background and Aim: Non- alcoholic fatty liver disease (NAFLD) is a prevalent metabolic liver disorder characterized by excessive triglyceride (TG) accumulation in hepatocytes and elevated hepatic free fatty acid flux. Aerobic and resistance training have been shown to reduce hepatic fat content, while probiotics may influence lipid metabolism by modifying energy extraction, synthesizing short- chain fatty acids, and improving the blood lipid profile. This study aimed to investigate the effects of moderate-intensity resistance training (MRT) and Lactobacillus reuteri supplementation on serum triglyceride and total cholesterol levels, as well as GRP78 gene expression in the livers of NAFLD- induced male Wistar rats.
Methods: In this experimental study, 32 male Wistar rats were randomly assigned to four groups: control, probiotic supplement, MRT, and MRT + probiotic. NAFLD was induced prior to intervention. The intervention lasted for 8 weeks. Serum triglyceride and total cholesterol levels were measured using ELISA. Hepatic GRP78 gene expression was assessed using PCR. Data were analyzed using one-way ANOVA followed by Bonferroni post hoc tests for group comparisons (p < 0.05 considered significant).
Results: Eight weeks of combined MRT and probiotic supplementation significantly increased GRP78 gene expression in liver tissue (from 0.06 to 1.01; p < 0.001). A significant reduction in total cholesterol was observed in the control (16.61 to 16.01 mg/dL) and probiotic (9.15 to 7.58 mg/dL) groups, while triglyceride levels decreased notably in the control group (41.5 to 28.68 mg/dL) (p < 0.05). The combined treatment group showed the most pronounced improvements in both lipid profile and gene expression.
Conclusion: Probiotic supplementation alone effectively reduced serum cholesterol levels, while its combination with MRT further enhanced the reduction in triglyceride levels. Moreover, the combined intervention significantly upregulated hepatic GRP78 expression, which may contribute to reduced lipogenesis and fat accumulation in the liver, suggesting potential therapeutic benefits in managing NAFLD.