title: Quercetin but not quercitrin ameliorates tumor necrosis factor-alpha-induced insulin resistance in C2C12 skeletal muscle cells.
abstract: Skeletal muscle is a major site for glucose metabolism and its injury by cytokines can induce insulin resistance leading to type 2 diabetes. It has been suggested that quercetin may act as an anti-diabetic agent, however, the effects of quercetin on insulin resistance in skeletal muscle remain unknown. We aimed to investigate the role of quercetin and its glycoside, quercitrin in tumor necrosis factor-alpha (TNF-α) induced C2C12 skeletal muscle cell impairment. Quercetin, but not quercitrin moderately attenuated the effects of TNF-α and enhanced the basal and insulin stimulated uptake of glucose in a dose-dependent manner via the activation of the protein kinase B (Akt) and AMP-activated protein kinase (AMPK) pathways. Furthermore, the underlying mechanism also involved the suppression of nuclear factor-κB (NF-κB) signaling and the nitric oxide (NO)/inducible nitric oxide synthase (iNOS) system, downstream of AMPK transduction. In summary, quercetin exhibited its effect of improving glucose uptake and insulin sensitivity in skeletal muscle cells via the two independent signaling pathways of Akt and AMPK, and can be developed as a potential anti-diabetic agent.
authors: Department of Nutrition and Food Hygiene, School of Public Health, Peking University Health Science Center, Haidian District, Beijing 100191, China.
authors: Xiaoqian
authors: X
authors: Dai
authors: Ye
authors: Y
authors: Ding
authors: Zhaofeng
authors: Z
authors: Zhang
authors: Xiaxia
authors: X
authors: Cai
authors: Lei
authors: L
authors: Bao
authors: Yong
authors: Y
authors: Li
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D005947:Glucose / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007333:Insulin Resistance / Q000502:physiology*; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000187:drug effects* / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011794:Quercetin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha
chemical_list: D007004:Hypoglycemic Agents; D016328:NF-kappa B; D009573:Nitrites; D014409:Tumor Necrosis Factor-alpha; C012526:quercitrin; D011794:Quercetin; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D051057:Proto-Oncogene Proteins c-akt; D055372:AMP-Activated Protein Kinases; D005947:Glucose