Radioprotective effect of sulphydryl group containing triazole derivative to modulate the radiation- induced clastogenic effects

Abstract

Protection of biological systems against radiation damage is of paramount importance during accidental and unavoidable exposure to radiation. Several physico-chemical and biological factors collectively contribute to the damage caused by radiation and are, therefore, targets for developing radioprotectors. Chemicals capable of scavenging free radicals, relieving oxidative stress, promoting antioxidant activity and modulating immune response have been some of the radioprotectors extensively investigated with limited success. It has long been known that some of the most effective radioprotective agents are those which contain sulphydryl groups. 4-amino-5-mercapto-3-methyl-1, 2, 4-triazole (AMMT) is one of the well-known 1, 2, 4 triazole derivatives with functional sulphydryl group. The present study reports an evaluation of radical scavenging and radioprotective properties of sulphydryl group containing triazole derivative. The lethal dose of electron beam radiation (EBR) was studied by survival assay. The dose reduction factor (DRF) of AMMT was calculated using the ratio between LD₅₀ of EBR with and without AMMT treatment. Radical scavenging property of AMMT was assessed by DPPH radical scavenging assay. The clastogenic effects of EBR were recorded by Micronucleus test in bone marrow cells and DNA fragmentation assay in mice hepatic cells. The survival assay results showed that the LD₅₀ of EBR was 10 Gy. The calculated DRF for AMMT was found to be 1.2. DPPH radical scavenging assay showed a positive result when it was compared with the standard glutathione. Treatment of mice with 100 mg of AMMT for 15 days before irradiation significantly (P<0.05) reduced the frequency of micronucleus formation in bone marrow cells and also reduced the DNA fragmentation in hepatic cells. The results obtained in the present study indicated that AMMT has a protective effect against the EBR-induced mortality and clastogenicity.