Department of Biochemistry, College of Pharmacy, Al-Azhar University, Cairo, Egypt.
Pharm Biol. 2012 Aug;50(8):1019-25. doi: 10.3109/13880209.2012.655424.
Quercetin, a dietary-derived flavonoid, is ubiquitous in fruits and vegetables and plays important roles in human health by virtue of its antioxidant activity.
This study was conducted to investigate the possible modulatory effect of quercetin against hepatic lipemic-oxidative injury in rats fed with a high cholesterol diet (HCD), and to highlight the underlying mechanisms of such effect.
Different groups of male Sprague-Dawley rats were used; one group was treated by gavage with HCD cocktail (1 mL/100 g) whereas another group was orally administered HCD-enriched with quercetin (15 mg/kg). Corresponding control animals were also used.
Quercetin administration significantly decreased liver triglycerides (24%), liver total cholesterol (TC) (22%), serum TC (20%), serum low-density lipoprotein cholesterol (31%), and duplicated serum high-density lipoprotein cholesterol (HDL-C). This study also revealed that quercetin administration significantly reduced the activity of serum alanine aminotransferase (41%), aspartate aminotransferase (51%), and γ-glutamyl transpeptidase (G-GT) (35%). Significant inhibition of thiobarbituric acid-reacting substances (40%), together with a valuable enhancement of reduced glutathione (GSH) content (53%) in the liver homogenates, was observed. In addition, quercetin-treated hypercholesterolemic animals exhibited a reasonable improvement of hepatic antioxidant enzymes. Moreover, serum and liver content of nitric oxide (NO) were markedly decreased in this model (26 and 25%, respectively), and were almost normalized following quercetin administration.
These data revealed that quercetin has the ability to ameliorate HCD-induced lipemic-oxidative injury in rat liver possibly through its antioxidant potential and/or increased NO bioavailability.
槲皮素是一种膳食衍生的类黄酮，广泛存在于水果和蔬菜中，因其抗氧化活性而对人体健康发挥着重要作用。
本研究旨在探讨槲皮素对高胆固醇饮食（HCD）喂养大鼠肝脂肪性氧化损伤的可能调节作用，并强调其作用机制。
使用不同组别的雄性 Sprague-Dawley 大鼠；一组通过灌胃给予 HCD 鸡尾酒（1ml/100g），另一组则口服给予 HCD 强化槲皮素（15mg/kg）。同时也使用了相应的对照动物。
槲皮素给药显著降低了肝脏甘油三酯（24%）、总胆固醇（TC）（22%）、血清 TC（20%）、血清低密度脂蛋白胆固醇（31%）和血清高密度脂蛋白胆固醇（HDL-C）（20%）。本研究还发现，槲皮素给药显著降低了血清丙氨酸氨基转移酶（41%）、天冬氨酸氨基转移酶（51%）和γ-谷氨酰转肽酶（G-GT）（35%）的活性。肝匀浆中的硫代巴比妥酸反应物质（40%）显著抑制，同时还原型谷胱甘肽（GSH）含量（53%）显著增加。此外，槲皮素治疗的高胆固醇血症动物表现出肝抗氧化酶的合理改善。此外，该模型中血清和肝脏中一氧化氮（NO）的含量明显降低（分别为 26%和 25%），给予槲皮素后几乎恢复正常。
这些数据表明，槲皮素具有改善 HCD 诱导的大鼠肝脂肪性氧化损伤的能力，可能是通过其抗氧化潜力和/或增加的 NO 生物利用度。
