Flavonoid-rich extract of Polygonum capitatum attenuates high-fat diet–induced atherosclerosis development and inflammatory and oxidative stress in hyperlipidemia rats

This research was carried out to investigate the effects of flavonoids ingredient from Polygonum capitatum (FPC) on blood lipid levels, vascular inflammation, and oxidative stress in high-fat diet (HFD) rats, as well as their mechanism of action. Rats fed with HFD for 6 weeks obviously displayed hyperlipidemia ( P < 0.01). Treatment with FPC at 90 and 180 mg/kg body weight significantly increased serum apolipoprotein A (ApoA) and high-density lipoprotein-cholesterol (HDL-C) levels and decreased serum apolipoprotein B (ApoB), triglyceride (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) levels of hyperlipidemia rats. FPC also improved the serum superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities and decreased serum malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) levels. Meanwhile, the result of reverse transcription polymerase chain reaction (RT-PCR) manifested that FPC upregulated the messenger RNA (mRNA) expression of low-density lipoprotein receptor (LDLR) and peroxisome proliferator–activated receptor α (PPARα) and downregulated the mRNA expression of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), acetyl CoA carboxylase (ACC), and sterol regulatory element-binding protein 1c (SREBP-1C) in the hepatic. These results demonstrated that FPC exerted anti-atherosclerosis effect in hyperlipidemia rats by regulating blood lipid metabolism, improving antioxidant ability, and modulating a proinflammatory profile and the expression levels of genes referred to lipogenesis and lipid oxidation, which might be attributed to flavonoid ingredients such as luteolin-7-O-glucoside, rutin, and quercitrin.