venom components of iranian scorpion hemiscorpius lepturus inhibit the growth and replication of human immunodeficiency virus 1 (hiv-1)

background: during the recent years, significant progress has been achieved on development of novel anti-viral drugs. natural products are assumed as the potential sources of novel anti-viral drugs; therefore, there are some previous studies reporting the anti-viral compounds from venomous animals. based on the significant value for tracing of non-toxic anti-viral agents from natural resources, this study was aimed to investigate the anti-viral activity of some hplc purified fractions derived from the venom of iranian scorpion, hemiscorpius lepturus, against human immunodeficiency virus 1 (hiv-1) and herpes simplex virus 1 (hsv-1). methods: h. lepturus crude venom was subjected to reverse phase hplc analysis to determine its active components precisely where four dominant fractions obtained at retention time of 156-160 minutes. the phospholipase a2 and hemolytic activities of the purified fractions were first evaluated. then the anti-viral activity was measured using single cycle hiv (nl4-3) replication and hsv (kos) plaque reduction assays. results: the h. lepturus crude venom inhibited hiv replication by 73% at the concentration of 200 µg/ml, while it did not show significant anti-hsv activity. it also inhibited the cell-free viral particles in a virucidal assay, while it showed no toxicity for the target cells in a proliferation assay. the four hplc fractions purified from h. lepturus inhibited hiv with ic50 of 20 µg/ml. conclusion: h. lepturus venom contains components with considerable anti-hiv activity insofar as it has virucidal activity that offers a novel therapeutic approach against hiv infection. our results suggest a promising pilot for anti-hiv drug discovery with h. lepturus scorpion venom.