Myocardial effects of ethanol consumption in the rat with streptozotocin-induced diabetes.
BACKGROUND
Rats with streptozotocin (STZ)-induced diabetes exhibit alterations in cardiac function, ventricular remodeling, and changes in cell signaling, which includes protein kinase C (PKC) isoforms. Moderate consumption of ethanol has a beneficial effect on cardiovascular outcomes in the general population, an effect that has recently been found to extend to patients with diabetes mellitus. We studied the effect of low-dose ethanol consumption on cardiac function, geometry, and PKC isoforms in the rat with STZ-induced diabetes.


METHODS
Four groups of rats were studied over 8 to 10 weeks: control, STZ-induced diabetes, 12% (v/v) ethanol consumption, and STZ-induced diabetes plus 4% (v/v) ethanol consumption. Invasive hemodynamic measurements were performed; myocardial tissue was obtained for analysis for total PKC and cytosolic and membrane protein content of PKC-alpha, PKC-delta, and PKC-epsilon, and two-dimensional and M-mode echocardiograms were obtained.


RESULTS
Compared with rats with diabetes alone, consumption of 4% ethanol prevented the decrease in left ventricular dP/dt seen with diabetes alone, as well as the increase in left ventricular internal dimension. Up-regulation of PKC-alpha, -delta, and -epsilon occurring in the diabetic animals was also prevented by ethanol consumption, whereas ethanol alone had no effect on PKC isoform pattern.


CONCLUSIONS
These data suggest that STZ-induced cardiac remodeling and dysfunction are associated with increases in PKC activity, particularly PKC-alpha, -delta, and -epsilon, and that consumption of ethanol can prevent these changes.
Section of Cardiology, Department of medicine, Louisiana State University Health Sciences Center, 1542 Tulane Avenue, New Orleans, LA 70112, USA. tgiles@lsumc.edu
Thomas D
TD
Giles
Michael B
MB
Given
Stan S
SS
Greenberg
Xinfang
X
Zhao
Edmund Kenneth
EK
Kerut
Elizabeth
E
McElwain
Gayle
G
Allen
D000428:Alcohol Drinking / Q000378:metabolism; D000818:Animals; D009202:Cardiomyopathies / Q000139:chemically induced / Q000201:enzymology* / Q000503:physiopathology; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology* / Q000503:physiopathology; D004195:Disease Models, Animal; D004789:Enzyme Activation / Q000187:drug effects; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D006334:Heart Function Tests; D006439:Hemodynamics / Q000187:drug effects; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D007527:Isoenzymes; D000431:Ethanol; D011493:Protein Kinase C