Chithra Pushpan K, Sindhu G, Shalini V, Parvathy Rathnam, Jayalekshmy Ananthasankaran, Helen Antony
Department of Biochemistry,University of Kerala,Kariavattom,Thiruvananthapuram,Kerala695581,India.
Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Industrial Estate PO, Papanamcode,Thiruvananthapuram,Kerala695019,India.
Br J Nutr. 2015 Apr 28;113(8):1207-19. doi: 10.1017/S0007114515000513. Epub 2015 Mar 30.
The present study was carried out to evaluate the anti-atherogenic effect of Njavara rice bran oil (NjRBO) on atherosclerosis by modulating enzymes and genes involved in lipid metabolism in rats fed a high-cholesterol diet (HCD). Adult male rats (Sprague-Dawley strain, weighing 100-120 g) were divided into three groups of nine animals each. Group I served as the control, group II were fed a HCD and group III were fed a HCD and NjRBO (100 mg/kg body weight). The study duration was 60 d. Serum and tissue lipid profile, atherogenic index, enzymes of lipid metabolism, plasma C-reactive protein levels, serum paraoxonase and arylesterase activities, thiobarbituric acid-reactive substances, gene and protein expression of paraoxonase 1 (PON1), PPARα, ATP-binding cassette transporter A1 (ABCA1), apoB and apoA1 in the liver were quantified. Total cholesterol, TAG, phospholipid, NEFA, LDL-cholesterol concentrations in the serum and liver, lipogenic enzyme activities, hepatic 3-hydroxy-3-methylglutaryl-CoA reductase activity and atherogenic index were significantly increased in HCD-fed rats, but they decreased after treatment with NjRBO. HDL-cholesterol level and lecithin cholesterol acyl transferase activity were increased in the NjRBO-treated group, but decreased in the HCD-fed group. The expression levels of ABCA1, apoA1, PON1 and PPARα were found to be significantly increased in NjRBO-treated group compared with the HCD-fed group; however, the expression level of apoB was found to be higher in HCD-fed group and lower in the NjRBO-treated group. These data suggest that NjRBO possesses an anti-atherogenic property by modulating lipid metabolism and up-regulating genes involved in reverse cholesterol transport and antioxidative defence mechanism through the induction of the gene expression PON1.
本研究旨在通过调节高胆固醇饮食（HCD）喂养大鼠的脂质代谢相关酶和基因，评估香稻麸皮油（NjRBO）对动脉粥样硬化的抗动脉粥样硬化作用。成年雄性大鼠（Sprague-Dawley品系，体重100-120 g）分为三组，每组九只动物。第一组作为对照组，第二组喂食HCD，第三组喂食HCD和NjRBO（100 mg/kg体重）。研究持续时间为60天。对血清和组织脂质谱、动脉粥样硬化指数、脂质代谢酶、血浆C反应蛋白水平、血清对氧磷酶和芳基酯酶活性、硫代巴比妥酸反应性物质、肝脏中对氧磷酶1（PON1）、PPARα、ATP结合盒转运体A1（ABCA1）、载脂蛋白B和载脂蛋白A1的基因和蛋白表达进行了定量分析。HCD喂养的大鼠血清和肝脏中的总胆固醇、甘油三酯、磷脂、非酯化脂肪酸、低密度脂蛋白胆固醇浓度、脂肪生成酶活性、肝脏3-羟基-3-甲基戊二酰辅酶A还原酶活性和动脉粥样硬化指数显著升高，但用NjRBO治疗后降低。NjRBO治疗组的高密度脂蛋白胆固醇水平和卵磷脂胆固醇酰基转移酶活性升高，而HCD喂养组降低。与HCD喂养组相比，NjRBO治疗组中ABCA1、载脂蛋白A1、PON1和PPARα的表达水平显著升高；然而，HCD喂养组中载脂蛋白B的表达水平较高，而NjRBO治疗组中较低。这些数据表明，NjRBO通过调节脂质代谢和通过诱导PON1基因表达上调参与逆向胆固醇转运和抗氧化防御机制的基因，具有抗动脉粥样硬化特性。
