Effects of Panax notoginseng saponins on PCSK9-LDLR expression and blood lipid metabolism in golden hamsters

AIM: To explore the regulatory effect of Panax notoginseng saponins (PNS) on hyperlipidemia in golden hamsters and its mechanism. METHODS: The hamsters (n=30) were randomly divided into 3 groups:normal group, model group, and PNS group. The animals in normal group was given common feed. The animals in other groups were given high-fat diet to construct a hyperlipidemia model. After induction for 4 weeks, the drugs were given by intraperitoneal injection for another 12 weeks. After the last drug given, the serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured by biochemical tests. The distribution and expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein receptor (LDLR) in liver were detected by real-time PCR, immunohistochemistry and Western blot. RESULTS: Compared with normal group, the serum levels of TC, TG, LDL-C and ALT in model group were increased significantly (P < 0.05). The expression of PCSK9 was increased, while the protein level of LDLR was decreased (P < 0.05). Compared with model group, the levels of TC, TG, LDL-C and ALT in PNS group were decreased significantly (P < 0.05), PCSK9 was mainly distributed in cytomembrane with decreased expression, and LDLR was mainly distributed in the cell membrane and plasma with increased expression. HDL-C and AST had no significant change during this time. CONCLUSION: Panax notoginseng saponins reduces the blood lipid levels in golden hamsters, which may be related to the regulation of PCSK9-LDLR signaling pathway.