Insulin-like and non-insulin-like action of vanadate in hepatocytes cultured in vitro.
The aim of this study was to determine possible insulin-mimetic effects of vanadate on amino acid transport, glycogen synthesis and glucose production in hepatocytes cultured in vitro. Vanadate, like insulin, caused a significant (100%) increase of amino acid transport. However, vanadate produced a significant (31%) decrease of 14C-glucose incorporation into glycogen, in contrast to insulin which caused a 54% increase. Vanadate also caused a significant decrease (24%) of basal glucose production but had no effect on glucagon-stimulated glucose production. Vanadate and insulin given together reduced more strongly the basal glucose production (68%) and also effectively prevented the glucagon-stimulated effect on glucose production. In hepatocytes cultured in vitro vanadate had insulin-like and non-insulin-like action. Our results clearly demonstrated that non-insulin-like effects of vanadate could have a beneficial influence on the therapy of diabetes type 2 causing a decrease of glucose production from the liver.
Rosa
Jagoda
J
Department of Physiology, School of Dentistry, University of Zagreb, Zagreb, Croatia. jrosa@mef.hr
Rosa
Josip
J
D026905:Amino Acid Transport Systems / Q000187:drug effects; D000818:Animals; D002478:Cells, Cultured; D005947:Glucose / Q000378:metabolism; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D008112:Liver Glycogen / Q000096:biosynthesis; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014638:Vanadates / Q000494:pharmacology*
D026905:Amino Acid Transport Systems; D007328:Insulin; D008112:Liver Glycogen; D014638:Vanadates; D005947:Glucose