The atheroprotective roles of heart-protecting musk pills against atherosclerosis development in apolipoprotein E-deficient mice.

Abstract

Heart-protecting musk pill (HMP), derived from Chinese herbal medicines, has been found to possess protective roles against atherosclerosis-related cardiovascular diseases (CVDs), however, the anti-atherosclerotic mechanisms of HMP are still unclear. Here, we investigated the effects of HMP on alleviating atherosclerotic lesion severity in mice and explored the molecular mechanisms. Apolipoprotein E-deficient mice were fed western-type diet supplemented with HMP (25 mg/kg/day) or normal saline gavage for 20 weeks. Then histopathological staining was performed to assess the atheromatous plaque burden. Biochemical kits were used to detect levels of lipid profiles. Moreover, effector factors associated with lipid metabolism in liver and intestinal tissues were investigated by western blot and real-time PCR assays. Levels of signal molecules participating in the mitochondrial-mediated apoptosis pathway were detected by Western blot. We found that HMP notably reduced atherosclerotic lesion size (P<0.05) and improved plaque stability (P<0.05). HMP treatment decreased circulating TC (P<0.01), LDL-C (P<0.01) and TG (P<0.05) levels and increased HDL-C (P<0.05) content. HMP was found to suppress SREBP2, HMGCR and PCSK9 expressions (P<0.05), yet promote LDLR expression (P<0.05) in hepatocytes. Moreover, HMP was discovered to activate PPARα/CPT-1A cascade (P<0.05) and inhibit contents of SREBP1c and the lipogenic genes FAS and ACCα (P<0.05). The LBK1/AMPK cascade was also activated after HMP administration (P<0.05). Additionally, HMP was found to facilitate transintestinal cholesterol excretion by increasing ABCG5 and ABCG8 levels and reducing NPC1L1 content (P<0.05). In terms of vasoprotective activities, we observed that HMP decreased cleaved caspase-3 content (P<0.05) in the vascular intima, which might be due to inhibition of mitochondrial-related signaling pathway. Altogether, our study indicates that HMP plays anti-atherosclerotic roles via regulating lipid metabolism and improving vascular intimal injury.