Nutrition and Obesity Group, Department of Nutrition and Food Science, Faculty of Pharmacy, Lascaray Research Center, University of the Basque Country (UPV/EHU), Vitoria, Spain.
Genes Nutr. 2014 Jan;9(1):361. doi: 10.1007/s12263-013-0361-7. Epub 2013 Dec 14.
Quercetin exhibits a wide range of biological functions. The first aim of the present work was to analyze the effects of quercetin on fat accumulation in adipose tissue and glycemic control in rats. Any potential involvement of muscle fatty acid oxidation in its effect on glycemic control was also assessed. Animals were fed a high-fat high-sucrose diet either supplemented with quercetin (30 mg/kg body weight/day), or not supplemented, for 6 weeks. One week before killing, a glucose tolerance test was carried out. Muscle triacylglycerol content, serum glucose, insulin, fructosamine and free fatty acids were measured, and homeostatic model assessment for insulin resistance (HOMA-IR) was calculated. The activities of lipogenic enzymes and lipoprotein lipase in adipose tissue, carnitine palmitoyl transferase-1b (CPT-1b) and citrate synthase in skeletal muscle, and the expression of several genes, ACO, CD36, CPT-1b, PPAR-α, PGC-1α, UCP3, TFAM and COX-2 in skeletal muscle were analyzed. Quercetin caused no significant reduction in body weight or adipose tissue sizes. However, fructosamine, basal glucose and insulin, and consequently HOMA-IR, were significantly reduced by quercetin. No changes were observed in the activity of lipogenic enzymes and lipoprotein lipase. Muscle triacylglycerol content was similar in both experimental groups. The expression of ACO, CD36, CPT-1b, PPAR-α, PGC-1α, UCP3, TFAM and COX-2 remained unchanged. It can be concluded that quercetin is more effective as an anti-diabetic than as an anti-obesity biomolecule. The improvement in insulin resistance induced by this flavonoid is not mediated by a delipidating effect in skeletal muscle.
槲皮素具有广泛的生物学功能。本研究的主要目的是分析槲皮素对脂肪组织脂肪积累和血糖控制的影响，并评估其对血糖控制作用是否涉及肌肉脂肪酸氧化。动物喂食高脂肪高蔗糖饮食，补充或不补充槲皮素（30mg/kg 体重/天），持续 6 周。在处死前一周进行葡萄糖耐量试验。测量肌肉三酰甘油含量、血清葡萄糖、胰岛素、果糖胺和游离脂肪酸，并计算胰岛素抵抗的稳态模型评估（HOMA-IR）。分析脂肪组织的脂肪生成酶和脂蛋白脂肪酶、骨骼肌中的肉碱棕榈酰转移酶-1b（CPT-1b）和柠檬酸合酶，以及骨骼肌中几种基因的表达，包括 ACO、CD36、CPT-1b、PPAR-α、PGC-1α、UCP3、TFAM 和 COX-2。槲皮素并未显著降低体重或脂肪组织大小。然而，槲皮素显著降低了果糖胺、基础葡萄糖和胰岛素，以及因此导致的 HOMA-IR。脂肪生成酶和脂蛋白脂肪酶的活性没有变化。两组肌肉三酰甘油含量相似。ACO、CD36、CPT-1b、PPAR-α、PGC-1α、UCP3、TFAM 和 COX-2 的表达保持不变。可以得出结论，槲皮素作为一种抗糖尿病生物分子比作为一种抗肥胖生物分子更有效。这种黄酮类化合物诱导的胰岛素抵抗的改善不是通过骨骼肌的去脂作用介导的。
