Estrogen weakens muscle endurance via estrogen receptor-p38 MAPK-mediated orosomucoid (ORM) suppression

Gender differences in fatigue manifest as females being more prone to feel exhaustion and having lower muscle endurance. However, the mechanisms of these effects remain unclear. We investigated whether orosomucoid, an endogenous anti-fatigue protein that enhances muscle endurance, is involved in this regulation. Female rats exhibited lower muscle endurance, and this gender difference disappeared in orosomucoid-1-deficient mice. Female rats also exhibited weaker orosomucoid induction in serum, liver and muscle in response to fatigue compared with male rats. Ovariectomy elevated orosomucoid levels and increased swimming time, and estrogen replenishment reversed these effects. Exogenous estrogen treatment in male and female mice produced opposite effects. Estrogen decreased orosomucoid expression and its promoter activity in C2C12 muscle and Chang liver cells in vitro, and estrogen receptor or p38 mitogen-activated protein kinase blockade abolished this effect. Therefore, estrogen negatively regulates orosomucoid expression that is responsible for the weaker muscle endurance in females.

Effect of auxiliary heterotopic partial liver transplantation on the pig with acute ischemic liver failure / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effect of auxiliary heterotopic partial liver transplantation on the pig with acute ischemic liver failure.</p><p><b>METHODS</b>When portal vein was shrinked more than 85 percent and artery was ligated or reserved, auxiliary heterotopic partial liver transplantation was performed in the pigs. The living condition, liver function, blood supply, pathological change and bile secretion of donor liver were observed, analysed and summarized.</p><p><b>RESULTS</b>In the artery-ligated pigs, the volume of original liver reduced and the hepatocytes were necrotic evidently. While in the artery-reserved pigs, the colour and hepatocytes of original liver were normal. The volume of donor liver augmented, and the hepatocytes lived and proliferated well.</p><p><b>CONCLUSIONS</b>Liver artery-ligated and portal vein-shrinker can result in acute ischemic liver failure, and auxiliary heterotopic partial liver transplantation is effective to treat this liver failure. reducing portal vein blood supply is little harmful to liver.</p>