Effects of Dapagliflozin in Combination with Hydrochlorothiazide on Cardiac Remodeling in Rats with Heart Failure After Myocardial Infarction.

In addition to its antihypertensive and diuretic effects, hydrochlorothiazide also demonstrates additional cardioprotective properties; however, the existence of a synergistic interaction between dapagliflozin and hydrochlorothiazide remains unclear.To establish a rat model of heart failure for investigating the effects and mechanisms of dapagliflozin in combination with hydrochlorothiazide during early intervention, H9c2 cells were cultured to validate their in vitro efficacy. The combination group exhibits a synergistic improvement in hemodynamics, ejection fraction, and a reduction in plasma B-type natriuretic peptide concentration. This combination effectively decreases collagen volume fraction and the expression of collagen I and III, p47phox, p67phox, NF-κB p65, Bax, and caspase-3. The combination group demonstrates a synergistic effect in enhancing cardiac function, attenuating oxidative stress and inflammation. The in vitro effects of the combination were demonstrated in H9c2 cardiomyocytes. In addition, the combination exhibits a more pronounced inhibitory effect on NHE1 expression. The expression of NHE1 in H9c2 cells is inhibited by hydrochlorothiazide, thereby alleviating the consequences of NHE1 overexpression. The results of molecular docking and kinetic simulations indicate a strong binding affinity (-6.1 kcal/mol) between hydrochlorothiazide and NHE1, resulting in the formation of a stable conformation. This may elucidate the underlying mechanism responsible for the synergistic effects of drugs.The combination of dapagliflozin and hydrochlorothiazide has synergistic effects on improving cardiac function, oxidative stress, and inflammation in rats with heart failure. Hydrochlorothiazide binds to and inhibits the expression of NHE1, thereby enhancing dapagliflozin's inhibitory effect on NHE activity. This mechanism potentially elucidates its enhanced cardioprotective effects.