RESUMO
BACKGROUND: Worldwide, cancer is still the primary cause of death, and one of the most widely used anthracyclines for treating cancer is doxorubicin (DOX). But a major worry is DOX-induced cardiomyopathy, which is primarily resulted from an excess of reactive oxygen species. Heart sarcoplasmic reticulum calcium ion ATPase2a (SERCA2a) controls the amount of calcium ions stored in the sarcoplasmic reticulum (SR). This study aims to evaluate and compare the efficacy of SERCA2a gene modified adipose mesenchymal stem cell-derived exosomes (AMSCs-dE) to nontransfected AMSCs-dE, in DOX induced cardiomyopathy in adult male albino rat. MATERIALS AND METHODS: Thirty one adult male albino rats were randomly divided into control group and DOX group that further subdivided into three DOX, AMSCs-dE and SERCA2a AMSCs-dE subgroups. AMSCs-dE were administered intravenously (IV). The levels of serum creatine kinase MB (CK-MB) were assessed after DOX injection and before sacrifice. Cardiac muscle samples were taken for histological analysis using Masson's trichrome and hematoxylin and eosin stains two months after the experiment. Proliferating cell nuclear antigen (PCNA) and connexin 43 were stained using immunohistochemistry. The expression of TNF and SERCA2a genes and proteins was measured by real-time polymerase chain reaction (PCR) and Western blot (Wb) analysis, respectively. Fluorescent microscopy demonstrated non-transfected and transfected exosomes labeled with PKH26 and GFP, respectively, in culture and cardiac muscle. RESULTS: DOX induced myocarditis progressing to degenerative and fibrotic changes in cardiac muscle that regressed in response to AMSCs-dE therapy. However, SERCA2a gene modified AMSCs-dE treatment reversed the mentioned parameters to nearly its normal level. CONCLUSIONS: These findings suggest that SERCA2a gene modification enhances the therapeutic efficacy of AMSCs-dE in treating DOX-induced cardiomyopathy.