Role of amino acids in modulating glucose-induced desensitization of the glucose transport system.

摘要: Abstract Amino acids were found to play an integral role in modulating glucose-induced desensitization of the glucose transport system (GTS). When adipocytes treated for 6 h a defined buffer containing 25 ng/ml insulin, 20 mM glucose, plus 15 amino Dulbecco's modified Eagle's medium, we observed marked GTS, manifested by 60% decrease maximal insulin responsiveness (MIR) and 2.5-fold reduction sensitivity. In contrast, little or no was seen under similar conditions absence acids. The ability co-regulate GTS appears be directly attributable per se since still cycloheximide-treated cells. Moreover, action is specific not required dexamethasone-induced GTS. Of contained one group 8 fully effective mediating loss both MIR sensitivity, whereas remaining 7 ineffective. Interestingly, this second selectively retained modulate Upon screening individual acids, that L-glutamine (but D-glutamine) as total MIR, glycine threonine only partially effective. Since isoleucine serine enhanced sensitivity protein synthesis without influencing it can influence several effector systems with notable differences rapidity action, direction regulation, specificity From these studies conclude: 1) requires three components--glucose, selective acids; 2) resistance induced through mechanisms, but 3) mediated primarily metabolic events independent de novo synthesis; 4) glutamine primary acid MIR. Overall, reveal important at cellular level provide new insights into mechanisms system.