Capsaicin improves blood sugar control and insulin response by changing gut bacteria and bile acid signals in diabetic mice

Capsaicin (CAP) treatment for 8 weeks markedly improves glucose tolerance and insulin sensitivity in type 2 diabetic db/db mice.

• CAP decreases gluconeogenesis and increases glycogen synthesis in the liver.
• The treatment inhibits the growth of the Lactobacillus genus and its bile salt hydrolase activity.
• This inhibition leads to an accumulation of tauro-β-muricholic acid, which antagonizes the farnesoid X receptor.
• Suppression of enterohepatic FXR-fibroblast growth factor 15 signaling may increase the bile acid pool size.
• Increased expression of cholesterol 7α-hydroxylase is associated with enhanced hepatic bile acid synthesis.
• Depleting gut microbiota with antibiotics negates the benefits of CAP on bile acid metabolism and glucose homeostasis.

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