Résumé
beta-glucan which is known as biological response modifiers and immunostimulator was investigated in this study to minimize the toxicity of chemo-and radiotherapy induced by cyclophosphamide [CYP] and radiation exposure in rats. beta-glucan was orally administered in a dose of 10 mg/kg b.wt. daily against the hazardous impacts of gamma-irradiation [1 Gy daily up to 10 Gy] and/or CYP [50 mg/kg b.wt. every other day for 2 weeks]. Determination of some biochemical analysis was carried out including calcium, alkaline phosphatase, creatine kinase, lactate dehydrogenase. Hematological analysis was performed on leucocytes and platelets counts. Additionally, histological study was also done on both lung and testis tissues. The experimental rats being sacrificed 1, 7 and 21 days post-treatment. Treatment with CYP induced significant decrease in WBCs, platelets counts and alkaline phosphatase activity and significant increase of creatine kinase and LDH activities accompanied by a significant increase in Ca level only at the end of experimental period. Similar results were recorded with irradiated group accompanied with a non significant change in Ca level allover the experimental periods. Combined treatment with both gamma-radiation and CYP intensified the effect of each other on most of the investigated parameters. Microscopic examination of the lung revealed that both gamma-irradiation and CYP showed disturbed structure of bronchioles, thickened alveolar walls together with scattered haemorrhagic areas. Signs of pneumonia and compensatory emphysema were also seen. Meanwhile, in testis, irregular seminiferous tubules with reduction in their sizes were observed. Besides, the intertubular spaces were fibrotic and devoid of Leyding cells. Bizarre-shaped spermatogenic cells were also prominent. In combined treatment, these lesions became much more progressed. However, glucan administration prior to treatment with CYP or gamma-radiation led to an improvement in most of biochemical, hematological and histological parameters under investigation. beta-glucan has a good protective role against the toxic effects associated with chemo-and radiotherapy