Red peppers with different pungencies and bioactive compounds differentially modulate energy and glucose metabolism in ovariectomized rats fed high fat diets

Abstract

We hypothesized that differences in red peppers pungencies and bioactive compounds are associated with different effects on obesity and glucose tolerance, and tested the hypothesis in ovariectomized (OVX) rats fed high fat diets. Increasing red pepper pungency was associated higher concentrations of capsaicin, dihydrocapsaicin and total capsaicinoids; and lower concentrations of β-carotene, total carotenoids and chlorogenic acid. After 8 weeks of consuming 1% different types of red peppers, moderately and severely pungent red peppers (MSP and SSP) improved energy homeostasis better than less pungent red pepper (LSP): MSP and SSP increased energy expenditure and decreased visceral fat mass. This was related to elevated uncoupling proteins (UCP)-1, UCP-2 and UCP-3 expressions and decreased expressions of genes involved in fatty acid synthesis. LSP enhanced insulin sensitivity and improved hepatic insulin signaling. In conclusion, red peppers with different color and pungency differently modulate energy and glucose homeostasis in OVX rats fed high fat diets.

Keywords

• Red pepper
• Capsaicin
• Oral glucose tolerance
• Hepatic insulin signaling