Aim of the work: this study demonstrated the drastic effects of ionizing radiation on the heart tissue of the adult male albino rats and the possible radio protective role of AFA extract.
Material and Methods: a total of forty-eight mature male albino rats (Rattus rattus) weighing 180-200g were fed on standard rodent pellets. Rats were equally categorized into four groups; each group contained 12 rats. These groups were: 1-untreated normal control rats (C); 2- rats exposed to 4Gy of gamma-radiation (Irradiated group R) and then they were sacrificed on days 5 and 21 (R1& R2 groups respectively) post-irradiation; 3- rats were treated orally with 94.5mg/kg body weight/day of AFA extract for 3 weeks (AFA group) and then they were sacrificed on 5 and 21 days (A1& A2 groups respectively) post- treatment; 4- rats were treated orally with 94.5mg/kg body weight/day of AFA extract for a period of one week before irradiation and three weeks after irradiation (AFA-irradiated group), then the rats were sacrificed on 5 and 21 days (AR1& AR2 groups respectively) post-irradiation and treatment, then the hearts were immediately excised.
Results: many drastic changes were observed in the cardiac muscle fibres of rats of R1 group. These changes included: numerous hemorrhagic areas which contained hemolyzed blood cells and some nuclei of myocardiocytes were pyknotic and others were hypertrophied with destruction in some fibres and widened endomysium. Aggravated changes were also observed in the heart of rats of R2 group such as highly elongated and congested cardiac blood vessels which contained hemolyzed blood cells and hemosiderin granules, numerous hemorrhagic areas, necrotic areas and widened endomysium. On the other hand, highly increased collagen fibres and amyloid-β deposits were also noticed in the cardiac tissues of rats of R1 and R2 groups with decreased PAS positive materials, total protein and DNA materials. Normal architecture of the cardiac muscle fibres was detected in the rats of A1, A2 groups with slightly increased collagen fibres and slightly decreased PAS positive materials, total protein, amyloid-β protein and DNA materials. Also, AR1, AR2 groups showed somewhat normal appearance and well developed cardiac muscle fibres, but some dilated endmysium spaces were still detected in the cardiac muscle fibres of rats of group AR2. Furthermore, increased collagen fibres and amyloid-β deposits were realized in the cardiac muscle fibres of rats of AR1, AR2 groups with decreased PAS positive materials, total protein and DNA materials.
Conclusions: AFA showed cardio- protective effect and powerful antioxidant action. So, it can be used under medical supervision as a natural supplement.