a comparative study of radioprotection by four indian medicinal herbs against genotoxicity induced by sub-lethal gamma irradiation in swiss albino mice

background: synthetic radio-protective agents like aminothiols are toxic and fda approved agent amifostine is no exception. some ayurvedic herbs have shown radioprotective potential. this study was carried out to test and compare the radioprotective potential of curcuma longa (cl) tinospora cordifolia (tc), zizyphus mauritiana (zm) and ocimum sanctum (os) against 2gy gamma irradiation in swiss albino mice. materials and methods: adult swiss albino mice from random breed colony were divided in to 6 groups (n=9), sham-control (sct), radiation control (ract), and four herb + radiation groups respectively. all except sct were exposed to whole body 2 gy of gamma radiation in a teletherapy unit and sct was sham exposed on day 7 of herb pretreatment (200mg/kg-bw orally by gavage). chromosomal studies from the bone marrow of femur by routine metaphase preparation after colchicine treatment were done in 3 animals from each group at 24, 72 and 168 hours after exposure. results: all four herbs showed significant radio-protective effects at 24 hrs. os, tc and zm showed nearly similar activity while cl showing the lowest activity. however the effects at 72 and 168 hrs showed highest protection by cl followed by zm |“| tc > os respectively suggesting that the well studied os was less effective at 72 and 168 hrs. conclusion: all the four herbs showed radioprotective potential with different efficacies at different time interval. iran. j. radiat. res., 2008 6 (1): 19- 30