Lactobacillus alleviated obesity induced by high-fat diet in mice.

Obesity is closely related to dyslipidaemia, diabetes and other metabolic syndromes. Long-term consumption of a high-fat diet (HFD) is an important risk factor that can lead to obesity. In the current research, three Lactobacillus strains, namely, Loigolactobacillus coryniformis subsp. torquens T3 (T3), Lacticasebacillus paracasei subsp. paracasei M5 (M5), and Lacticaseibacillus paracasei subsp. paracasei X12 (X12), were tested to determine their inhibitory effects on HFD-induced obesity. The results showed that M5, T3, and X12 significantly decreased the body weight gain, Lee's index and adipose index. T3 showed significant effects on reducing serum TG levels to 0.92 mmol/ml and increasing HDL-C levels to 2.18 mmol/ml. The M5 treatment significantly reduced the serum TG level and leptin content to 1.11 mmol/ml and 3.7 ng/ml, respectively, and it increased the HDL-C level and adiponectin content to 2.35 mmol/ml and 7 ng/ml, respectively. M5 and T3 dramatically ameliorated hepatic steatosis in HFD-treated mice by reducing the liver index, lipid droplet number in the liver and TC levels in the liver. Gene expression of PPAR-γ and TNF-α was notably downregulated and FAS was upregulated by T3 and M5 treatment. Additionally, administration of M5 and T3 modified the diversity of the gut microbiota with increased OTU number, ACE index, and Chao1, and decreased the Shannon index and the Bacteroidetes /Firmicutes ratio. Overall, our results indicate that Lactobacillus may be used to prevent obesity and gut dysbiosis. PRACTICAL APPLICATION: Lactobacillus from traditional Chinese foods showed strong anti-obesity effects on high-fat diet-fed mice through the regulation of adipocytokines. Additionally, administration of certain Lactobacilli modified the diversity of the gut microbiota. The results indicate that Lactobacillus may be promising functional materials in healthy foods.