The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Effect of insulin and plasma amino acid concentration on leucine metabolism in cirrhosis.

Clinically stable patients with cirrhosis demonstrate insulin resistance with regard to glucose metabolism. However, much less is known about the two major factors, insulin and plasma amino acid concentration, that regulate protein metabolism in cirrhotic patients. To examine this question, we performed paired euglycemic insulin clamp studies in combination with 14C-leucine and indirect calorimetry. In the first study insulin alone was infused, and the plasma amino acid concentration was allowed to decline. During the second study a balanced amino acid solution was infused with insulin to increase the total plasma amino acid concentration approximately twofold. Insulin-mediated glucose disposal (4.68 vs. 6.45 mg/kg-min, p less than 0.01) was significantly impaired by 30% in cirrhotic patients during both insulin clamp studies. In the postabsorptive state, cirrhotic patients manifested low plasma leucine (76 vs. 102 mumol/L) and alpha-ketoisocaproate (19 vs. 30 mumol/L) concentrations, but all parameters of leucine turnover were normal. When insulin alone was infused, the endogenous leucine flux (an index of protein degradation) declined similarly in cirrhotic patients (30.8 mumol/m2-min) and control (26.9) subjects, and this was accompanied by a similar decrease in plasma leucine concentration (31% vs. 33%). The decline in circulating leucine concentration was accompanied by a parallel decline in leucine oxidation (5.1 vs. 4.6 mumol/m2-min) and nonoxidative (28.9 vs. 26.0 mumol/m2-min) leucine disposal, which were of similar magnitude in cirrhotic patients and control subjects, respectively. In both cirrhotic patients and control subjects, combined hyperinsulinemia/hyperaminoacidemia elicited a similar stimulation of nonoxidative leucine disposal (an index of protein synthesis) and leucine oxidation while causing a greater suppression of endogenous leucine flux than observed with insulin alone. Thus the suppressive effect of insulin on protein degradation and the stimulatory effect of insulin/amino acid infusion on protein synthesis are not impaired in cirrhotic patients, demonstrating a clear-cut dissociation between the effects of insulin on protein and glucose metabolism.[1]


  1. Effect of insulin and plasma amino acid concentration on leucine metabolism in cirrhosis. Petrides, A.S., Luzi, L., Reuben, A., Riely, C., DeFronzo, R.A. Hepatology (1991) [Pubmed]
WikiGenes - Universities