IntroductionAtorvastatin and sitagliptin are able to exert cardio-protective effects. However, whether atorvastatin plus sitagliptin could confer additive benefits for rats with myocardial infarction (MI) is unknown.Material and methodsForty rats with MI were produced and 37 surviving rats were randomly divided into atorvastatin (10 mg/kg daily, n = 9), sitagliptin (10 mg/kg daily, n = 9), combined (10 mg/kg daily atorvastatin plus 10 mg/kg daily sitagliptin, n = 9), and control groups (3 ml normal saline daily, n = 10). Fourteen days later, cardiac function was detected and fasting venous blood was sampled for lipid profiles and glucose evaluation. Cardiac tissues were used for hematoxylin-eosin staining, for interleukin-6 (IL-6) and tumor necrotic factor-α (TNF-α) evaluation, and for rho-associated kinase 2 (ROCK2) assessment.ResultsFourteen days after MI, the inflammatory reaction regarding the degree of leukocyte infiltration and IL-6 and TNF-α expression in cardiac tissues was ameliorated in atorvastatin and sitagliptin groups compared to the control group (p < 0.05). In addition, ROCK2 was attenuated by either atorvastatin or sitagliptin (p < 0.05). Echocardiography showed that cardiac function was significantly improved with atorvastatin and sitagliptin therapy (p < 0.05). Overall, all these benefits were further enhanced by combined therapy, suggesting that atorvastatin combined with sitagliptin therapy has additive effects on reducing cardiac inflammation and improving cardiac function. No significant changes in lipid profiles or glucose were observed, suggesting that the benefits derived from atorvastatin and sitagliptin therapy might not depend on cholesterol and glucose modulation.ConclusionsIn rats with MI, atorvastatin plus sitagliptin therapy provides additive effects for cardio-protection, and mechanisms operating in these processes may be due to ROCK2 diminishment.