Effective probiotics alleviate obesity induced by high-fat diet by regulating bile acid and short-chain fatty acid metabolism

High-fat diet can cause individuals to metabolic syndrome, including obesity, dyslipidemia, nonalcoholic fatty liver, fat accumulation, and chronic inflammation. The purpose of this study was to identify effective probiotic strains that mitigate high-fat diet–induced obesity and elucidate their underlying mechanisms. Golden hamsters, which exhibit lipid metabolism profiles most similar to humans, were used as the experimental model. In this study, we evaluated the efficacy of four Bifidobacterium in alleviating obesity induced by high-fat diet. Three effective probiotics, Bifidobacterium animalis subsp. lactis C-1 (B. lactis C-1), Bifidobacterium animalis subsp. lactis C-2 (B. lactis C-2), and Bifidobacterium longum subsp. longum C-5 (B. longum C-5) effectively reduced weight gain, improved serum lipid, decreased fat accumulation, and attenuating hepatic injury and systemic inflammation. Mechanistically, the effective probiotics enhanced bile salt hydrolase (BSH) activity and Clostridium scindens, promoting fecal bile acid excretion, reducing intestinal lipid absorption and bile acid reabsorption, which was alleviating obesity induced high-fat diet. Moreover, the effective probiotics alleviated high-fat diet–induced systemic inflammation and hepatic injury by increasing short-chain fatty acids (SCFAs) in the gut. In contrast, Bifidobacterium longum subsp. infantis CK2010 (B. infantis CK2010) showed limited effects. The study provided an in-depth mechanistic insight, detailing the gut microbes and metabolites which mediate the effects of the effective probiotics.