Objective: To evaluate the effects of valsartan and carnitine on cardiomyocyte Calpain-1 and Bcl-xl expressions of dogs with chronic alcohol intake-induced cardiomyopathy.
Methods: Dogs were randomly assigned into 4 groups (n = 7 each): (1) alcohol fed (free access to 5%, 1(st) week; 10% 2(nd) week; 500 ml 25% bolus plus free access to 5% from 3 to 24 weeks, A); (2) alcohol + valsartan (5 mg×kg(-1)×d(-1), B); (3) alcohol + carnitine (300 mg×kg(-1)×d(-1), C); (4) Control (D). After six months, all animals were assessed for left ventricular (LV) function by echocardiography. The Bad and Bcl-xl protein expressions were evaluated by immunohistochemistry. The expression of Calpain-1 protein was determined with Western blot. Myocardial morphology was quantified on HE stained slices and under electron microscopy. The terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) was performed for apoptosis analysis.
Results: Compared with group D, LVEDD and LVESD were significantly increased while EF and FS significantly decreased in group A. In alcohol fed group, expressions of Bad and Calpain-1 protein were significantly increased while Bcl-xl protein expression was downregulated, all changes could be significantly attenuated by intervention with valsartan and carnitine (all P < 0.05).
Conclusion: These data suggest that alcohol could promote cardiac myocyte apoptosis, reduce cardiac function and aggravate myocardial remodeling which valsartan and carnitine could reduce alcoholic cardiomyopathy by downregulating Calpain-1 and Bad protein expression and upregulating expression of Bcl-xl protein.