tailieunhanh - Báo cáo y học: "Insulin alleviates degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system in septic rats"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Insulin alleviates degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system in septic rats. | Chen et al. Journal of Inflammation 2011 8 13 http content 8 1 13 JOURNAL OF INFLAMMATION RESEARCH Open Access Insulin alleviates degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system in septic rats Qiyi Chen Ning Li Weiming Zhu Weiqin Li Shaoqiu Tang Wenkui Yu Tao Gao Juanjuan Zhang and Jieshou Li Abstract Hypercatabolism is common under septic conditions. Skeletal muscle is the main target organ for hypercatabolism and this phenomenon is a vital factor in the deterioration of recovery in septic patients. In skeletal muscle activation of the ubiquitin-proteasome system plays an important role in hypercatabolism under septic status. Insulin is a vital anticatabolic hormone and previous evidence suggests that insulin administration inhibits various steps in the ubiquitin-proteasome system. However whether insulin can alleviate the degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system under septic condition is unclear. This paper confirmed that mRNA and protein levels of the ubiquitin-proteasome system were upregulated and molecular markers of skeletal muscle proteolysis tyrosine and 3-methylhistidine simultaneously increased in the skeletal muscle of septic rats. Septic rats were infused with insulin at a constant rate of for 8 hours. Concentrations of mRNA and proteins of the ubiquitin-proteasome system and molecular markers of skeletal muscle proteolysis were mildly affected. When the insulin infusion dose increased to mRNA for ubiquitin E2-14 KDa and the C2 subunit were all sharply downregulated. At the same time the levels of ubiquitinated proteins E2-14KDa and the C2 subunit protein were significantly reduced. Tyrosine and 3-methylhistidine decreased significantly. We concluded that the ubiquitin-proteasome system is important skeletal muscle hypercatabolism in septic rats. Infusion of insulin can reverse the detrimental metabolism of .