Abstract 451: PNS-R1 Attenuates the Development of Atherosclerosis in ApoE-Deficient Mouse Model

Abstract

Atherosclerosis is a chronic pathological condition featured by accumulation of lipids and fibrous elements in the artery. Atherosclerosis remains as the primary cause of cardiovascular diseases and agents that effectively intervenes the development of atherosclerosis are still needed. Panax notoginseng has been extensively used as therapeutic agent in Asia to treat cardiovascular disorders. Panax notoginseng saponins (PNS) is the major class of active components of Panax notoginseng. PNS has been reported to possess anti-atherosclerotic effect. However, which component of PNS is responsible for this effect remains unknown. The current study evaluated the effects of a component unique to PNS, PNS-R1, on atherosclerosis in ApoE-/- mouse model. Histological examination revealed that the extent of atherosclerotic lesion was significantly alleviated in PNS-R1-treated ApoE-/- mice compared to that from the ApoE-/- controls. Meanwhile, PNS-R1 treatment significantly reduced the level of oxidative stress in the atherosclerotic lesion, which was prominently enhanced in ApoE-/- controls. This effect on oxidative stress was corroborated by increased serum level of GSH and SOD and decreased level of MDH in PNS-treated mice. Furthermore, PNS-R1 treatment significantly decreased the levels of total cholesterol, triglycerides and increased the level of HDL without affecting the level of LDL, suggesting an effect of PNS-R1 on lipid metabolism, which could in part contribute to its action in attenuating atherosclerosis. Additionally, the levels of inflammatory factors including IL-2, IL-6, TNF-α, γ-IFN and ox-LDL were markedly reduced in PNS-R1-treated mice compared to that from the ApoE-/- controls, demonstrating a significant anti-inflammatory effect of PNS-R1 in the development of atherosclerosis. Expression of microRNAs known to be involved in the pathogenesis of atherosclerosis was further evaluated and showed that PNS-R1 treatment led to a significant reduction in the expression of miR-122, miR-132 and miR-155. Collectively, our results provided for the first time the experimental evidence supporting the anti-atherosclerotic effects of PNS-R1, which could be a promising therapeutic agent treating atherosclerosis.