Backgroud: Saussurea involucrata Kar. et Kir. (Compositae) (CCSauI) cells are rich in caffeoylquinic acids (CQAs), which have plasma lipid reducing properties and anti-obesity effects, although the mechanisms remain unclear. Clarify CQA’s anti-obesity mechanism and provide new treatments for obesity.
Methods: Sprague Dawley (SD) rat were fed a high-fat diet (HFD), then CQAs was intragastric administrated (0.1, 0.5 or 1 mg/mL). Rats were randomly divided into five groups (n=30): NC, MC, TPL (0.1 mg/mL), TPM (0.5 mg/mL) and TPH (1 mg/mL). Digestive enzyme inhibition was obtained by measuring the inhibition rate of α-amylase, α-glucosidase, and pancreatic lipase in vitro. Anti-obesity function was detected by determining the content of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), malondialdehyde (MDA) superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). To analyze the related mechanisms qRT-PCR was employed.
Results: From in vitro enzyme activity assays, the IC50 values of the CQAs extract for α-amylase, α-glucosidase, and lipase were 0.631, 0.31, and 0.438 mg/mL, respectively. CQAs administration for 8 weeks decreased retroperitoneal fat and serum and liver TC, TG, LDL-C, and MDA. Comparatively, levels of HDL-C, SOD, and GSH-Px were increased. Real-time fluorescent quantitative PCR showed inhibited expression of fatty acid synthase and 3-hydroxy-3-methyl glutaryl and coenzyme A reductase, peroxisome proliferator-activated receptor-α activation, and 7α-hydroxylase promotion.
Conclusion: This study explored the role of CQAs in inhibiting digestive enzyme activities and up-regulating the expression of lipase, significant for prevention and treatment of diabetes and obesity.