AMP-activated protein kinase influences metabolic remodeling in H9c2 cells hypertrophied by arginine vasopressin.

TitleAMP-activated protein kinase influences metabolic remodeling in H9c2 cells hypertrophied by arginine vasopressin.
Publication TypeJournal Article
Year of Publication2009
AuthorsSaeedi, R, Saran, VV, S Y Wu, S, Kume, ES, Paulson, K, Chan, APK, Parsons, HL, Wambolt, RB, Dyck, JRB, Brownsey, RW, Allard, MF
JournalAm J Physiol Heart Circ Physiol
Volume296
Issue6
PaginationH1822-32
Date Published2009 Jun
ISSN0363-6135
KeywordsAMP-Activated Protein Kinases, Animals, Arginine Vasopressin, Autocrine Communication, Calcium, Cardiomegaly, Cell Line, Energy Metabolism, Glucose, Glycolysis, Myocytes, Cardiac, Paracrine Communication, Pyrazoles, Pyrimidines, Rats, Vasoconstrictor Agents
Abstract

Substrate use switches from fatty acids toward glucose in pressure overload-induced cardiac hypertrophy with an acceleration of glycolysis being characteristic. The activation of AMP-activated protein kinase (AMPK) observed in hypertrophied hearts provides one potential mechanism for the acceleration of glycolysis. Here, we directly tested the hypothesis that AMPK causes the acceleration of glycolysis in hypertrophied heart muscle cells. The H9c2 cell line, derived from the embryonic rat heart, was treated with arginine vasopressin (AVP; 1 microM) to induce a cellular model of hypertrophy. Rates of glycolysis and oxidation of glucose and palmitate were measured in nonhypertrophied and hypertrophied H9c2 cells, and the effects of inhibition of AMPK were determined. AMPK activity was inhibited by 6-[4-(2-piperidin-1- yl-ethoxy)-phenyl]-3-pyridin-4-yl-pyrrazolo-[1,5-a]pyrimidine (compound C) or by adenovirus-mediated transfer of dominant negative AMPK. Compared with nonhypertrophied cells, glycolysis was accelerated and palmitate oxidation was reduced with no significant alteration in glucose oxidation in hypertrophied cells, a metabolic profile similar to that of intact hypertrophied hearts. Inhibition of AMPK resulted in the partial reduction of glycolysis in AVP-treated hypertrophied H9c2 cells. Acute exposure of H9c2 cells to AVP also activated AMPK and accelerated glycolysis. These elevated rates of glycolysis were not altered by AMPK inhibition but were blocked by agents that interfere with Ca(2+) signaling, including extracellular EGTA, dantrolene, and 2-aminoethoxydiphenyl borate. We conclude that the acceleration of glycolysis in AVP-treated hypertrophied heart muscle cells is partially dependent on AMPK, whereas the acute glycolytic effects of AVP are AMPK independent and at least partially Ca(2+) dependent.

DOI10.1152/ajpheart.00396.2008
Alternate JournalAm. J. Physiol. Heart Circ. Physiol.
PubMed ID19376807