INRA UMR, Dynamique Musculaire et Métabolisme, Université Montpellier, Montpellier, France.
Br J Nutr. 2011 Aug;106(4):491-501. doi: 10.1017/S0007114511000602. Epub 2011 Apr 20.
Accumulation of muscle TAG content and modification of muscle phospholipid fatty acid pattern may have an impact on lipid metabolism, increasing the risk of developing diabetes. Some polyphenols have been reported to modulate lipid metabolism, in particular those issued from red grapes. The present study was designed to determine whether a grape polyphenol extract (PPE) modulates skeletal muscle TAG content and phospholipid fatty acid composition in high-fat-high-sucrose (HFHS) diet-fed rats. Muscle plasmalemmal and mitochondrial fatty acid transporters, GLUT4 and lipid metabolism pathways were also explored. The PPE decreased muscle TAG content in HFHS/PPE diet-fed rats compared with HFHS diet-fed rats and induced higher proportions of n-3 PUFA in phospholipids. The PPE significantly up-regulated GLUT4 mRNA expression. Gene and protein expression of muscle fatty acid transporter cluster of differentiation 36 (CD36) was increased in HFHS diet-fed rats but returned to control values in HFHS/PPE diet-fed rats. Carnitine palmitoyltransferase 1 protein expression was decreased with the PPE. Mitochondrial β-hydroxyacyl CoA dehydrogenase was increased in HFHS diet-fed rats and returned to control values with PPE supplementation. Lipogenesis, mitochondrial biogenesis and mitochondrial activity were not affected by the PPE. In conclusion, the PPE modulated membrane phospholipid fatty acid composition and decreased muscle TAG content in HFHS diet-fed rats. The PPE lowered CD36 gene and protein expression, probably decreasing fatty acid transport and lipid accumulation within skeletal muscle, and increased muscle GLUT4 expression. These effects of the PPE are in favour of a better insulin sensibility.
肌肉 TAG 含量的积累和肌肉磷脂脂肪酸模式的改变可能会影响脂质代谢，增加患糖尿病的风险。一些多酚已被报道能调节脂质代谢，特别是那些来自红葡萄的多酚。本研究旨在确定葡萄多酚提取物（PPE）是否能调节高脂肪高蔗糖（HFHS）饮食喂养大鼠的骨骼肌 TAG 含量和磷脂脂肪酸组成。还探讨了肌肉质膜和线粒体脂肪酸转运体、GLUT4 和脂质代谢途径。与 HFHS 饮食喂养的大鼠相比，HFHS/PPE 饮食喂养的大鼠肌肉 TAG 含量降低，并且磷脂中 n-3PUFA 的比例更高。PPE 显著上调 GLUT4 mRNA 表达。HFHS 饮食喂养的大鼠肌肉脂肪酸转运蛋白 CD36 的基因和蛋白表达增加，但 HFHS/PPE 饮食喂养的大鼠则恢复到对照值。肉碱棕榈酰基转移酶 1 蛋白表达随 PPE 降低。线粒体β-羟酰基辅酶 A 脱氢酶在 HFHS 饮食喂养的大鼠中增加，而 PPE 补充则使其恢复到对照值。PPE 对脂生成、线粒体生物发生和线粒体活性没有影响。总之，PPE 调节了膜磷脂脂肪酸组成，并降低了 HFHS 饮食喂养大鼠的肌肉 TAG 含量。PPE 降低了 CD36 的基因和蛋白表达，可能减少了骨骼肌内的脂肪酸转运和脂质积累，并增加了肌肉 GLUT4 的表达。PPE 的这些作用有利于提高胰岛素敏感性。
