Statins aggravate insulin resistance through reduced blood glucagon-like peptide-1 levels in a microbiota-dependent manner.

Statins are currently the most common cholesterol-lowering drug, but the underlying mechanism of statin-induced hyperglycemia is unclear. To investigate whether the gut microbiome and its metabolites contribute to statin-associated glucose intolerance, we recruited 30 patients with atorvastatin and 10 controls, followed up for 16 weeks, and found a decreased abundance of the genus Clostridium in feces and altered serum and fecal bile acid profiles among patients with atorvastatin therapy. Animal experiments validated that statin could induce glucose intolerance, and transplantation of Clostridium sp. and supplementation of ursodeoxycholic acid (UDCA) could ameliorate statin-induced glucose intolerance. Furthermore, oral UDCA administration in humans alleviated the glucose intolerance without impairing the lipid-lowering effect. Our study demonstrated that the statin-induced hyperglycemic effect was attributed to the Clostridium sp.-bile acids axis and provided important insights into adjuvant therapy of UDCA to lower the adverse risk of statin therapy.

Glycoursodeoxycholic acid ameliorates diet-induced metabolic disorders with inhibiting endoplasmic reticulum stress.

Recent studies reveal that bile acid metabolite composition and its metabolism are changed in metabolic disorders, such as obesity, type 2 diabetes and metabolic associated fatty liver disease (MAFLD), yet its role and the mechanism remain largely unknown. In the present study, metabolomic analysis of 163 serum and stool samples of our metabolic disease cohort was performed, and we identified glycoursodeoxycholic acid (GUDCA), glycine-conjugated bile acid produced from intestinal bacteria, was decreased in both serum and stool samples from patients with hyperglycemia. RNA-sequencing and quantitative PCR results indicated that GUDCA alleviated endoplasmic reticulum (ER) stress in livers of high fat diet (HFD)-fed mice without alteration of liver metabolism. In vitro, GUDCA reduced palmitic acid induced-ER stress and -apoptosis, as well as stabilized calcium homeostasis. In vivo, GUDCA exerted effects on amelioration of HFD-induced insulin resistance and hepatic steatosis. In parallel, ER stress and apoptosis were decreased in GUDCA-treated mice as compared with vehicle-treated mice in liver. These findings demonstrate that reduced GUDCA is an indicator of hyperglycemia. Supplementation of GUDCA could be an option for the treatment of diet-induced metabolic disorders, including insulin resistance and hepatic steatosis, with inhibiting ER stress.