Background: Excessive consumption of dietary fat is closely related to obesity, diabetes, insulin resistance, cardiovascular disease, hypertension, and non-alcoholic fatty liver disease. Recently, probiotics have been highly proposed as biotherapeutic to treat and prevent diseases. Previously, there are studies that demonstrated the beneficial effects of probiotics against metabolic disorders, including obesity and diabetes.
Objective: We investigated the anti-obesity effect and mechanism of action of four human-derived lactic acid bacterial (LAB) strains (Lacticaseibacillus rhamnosus MG4502, Lactobacillus gasseri MG4524, Limosilactobacillus reuteri MG5149, and Weissella cibaria MG5285) in high-fat diet (HFD)-induced obese mice.
Design: Obesity was induced in mice over 8 weeks, with a 60% HFD. The four human-derived LAB strains (2 × 108 CFU/mouse) were orally administered to male C57BL/6J mice once daily for 8 weeks. Body weight, liver and adipose tissue (AT) weights, glucose tolerance, and serum biochemistry profiles were determined. After collecting the tissues, histopathological and Western blot analyses were conducted.
Results: Administration of these LAB strains resulted in decreased body weight, liver and AT weights, and glucose tolerance. Serum biochemistry profiles, including triglyceride (TG), total cholesterol, low-density lipoprotein cholesterol, and leptin, pro-inflammatory cytokines, improved. Hepatic steatosis and TG levels in liver tissue were significantly reduced. In addition, the size of adipocytes in epididymal tissue was significantly reduced. In epididymal tissues, Limosilactobacillus reuteri MG5149 and Weissella cibaria MG5285 groups showed a significantly reduced expression of lipogenic proteins, including peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, fatty acid synthase (FAS), and adipocyte-protein 2. In addition, sterol regulatory element-binding protein 1-c and its downstream protein FAS in the liver tissue were significantly decreased. These strains attenuated fat accumulation in the liver and AT by upregulating the phosphorylation of AMP-activated protein kinase and acetyl-CoA carboxylase in HFD-fed mice.
Conclusion: We suggest that L. reuteri MG5149 and W. cibaria MG5285 could be used as potential probiotic candidates to prevent obesity.