Cardioprotective effect of antioxidant combination therapy: A highlight on MitoQ plus alpha-lipoic acid beneficial impact on myocardial ischemia-reperfusion injury in aged rats.

OBJECTIVE: (s): Considering the poor prognosis of ischemic heart disease and the diminished effectiveness of cardioprotective interventions in the elderly, it becomes necessary to investigate the interaction of aging with protection during myocardial ischemia/reperfusion injury (IRI). This study was conducted to assess the impact of mitoquinone (MitoQ) and alpha-lipoic acid (ALA) preconditioning on cardioprotection following IRI in aged rats.

METHODS: Fifty aged male Wistar rats (22-24 months old) were divided into five groups including Sham, IR, and treatment groups receiving ALA and/or MitoQ. Treatment groups were received 100 mg/kg/day ALA by oral gavage and/or 10 mg/kg/day MitoQ by intraperitoneal injection for 14 consecutive days. An in vivo model of myocardial IRI was established through ligation of coronary artery for 30 min and it's reopening for 24 h. The left ventricles were removed at the end of reperfusion to assess oxidative stress indicators, mitochondrial function, and expression of mitochondrial dynamic genes. Myocardial infarct size (IS), hemodynamic parameters, and serum lactate dehydrogenase (LDH) level were also measured.

RESULTS: Combination of MitoQ and ALA reduced oxidative stress, LDH level, and IS in aged hearts subjected to IRI. It also enhanced mitochondrial function and upregulated Mfn1, Mfn2, and Foxo1 and downregulated Drp1 and Fis1 gene expression. Co-administration of MitoQ and ALA partially restored IRI-induced hemodynamic changes to normal state. In all measured parameters, the effect of combined treatment was greater than monotherapies.

CONCLUSION: The combination therapy of MitoQ and ALA demonstrated considerable therapeutic potential in protecting the aging heart against IRI by improving oxidative stress, mitochondrial function, and dynamics in aged rats.