Cardiotoxicity is an important lethal complication of several cancer therapeutic agents. Clearly, DNA damaging chemotherapy treatments may cause damage to both cancer and healthy cells to generate toxic side-effects. We aimed to demonstrate and to compare the possible therapeutic effect of bone marrow mesenchymal stem cells, their Exosomes and Vitamin E on induced cardio toxicity in adult male albino rats.This work was performed on 60 adult male albino rats subdivided into 5 groups Group I (-ve control) Group III (CP plus BM-MSCs) Group IV (CP plus Exosomes group) Group V (CP plus Vitamin E) Ten rats were used to isolate the BM-MSCs and their Exosomes. Tissue sections were prepared for light microscope examination by staining with Hematoxyline & Eosin and Masson’s Trichrome, and for immunohistochemical staining for proliferating cell nuclear antigen (PCNA).The use of bone marrow mesenchymal stem cells (BM-MSCs) after administration of Cyclophosphamide (CP) showed marked reduction in the cardiac toxic effect which appeared in improvement of CP induced pathological changes on the cardiac muscle fibers detected by light microscopic examination whilethe use of their exosomes and vit. E after administration of CP, showed moderate and mild improvement of CP induced pathological changes on the cardiac muscle fibers, respectively.Bone marrow mesenchymal stem cells, their exosomes and vit.E have beneficial effect in CP induced cardiotoxicity while statistical analysis revealed that bone marrow mesenchymal stem cells was superior to exosomes and vit. E as a potent therapeutic agent against Cyclophosphamide cardiac toxicity. We speculate that the beneficial effect cannot be explained only by antioxidant effect but also by the immunogenic and pleiotropic effects of MSCs |