Studies on Inhibitory Effect of M elanin on the Apoptosis Induced by Influenza Virus in Host Cells

The apoptosis induced by influenza virus in cultured MDCK cells was reported and the selective inhibitory effect of melamin on the apoptosis induced by influenza virus was investigated. The results showed that the DNA ladder could be first detected at 6 h post infection (p.i.), accompanied by nuclear condensation and nuclear fragmentation could be easily detected at 12 h p.i. In addition, the apoptosis induced activity of influenza virus A1/Jingfang 86 1 strain was more potent than that of B/Hufang 93 1 strain (P0.05). In the range of 20-125 g/mL, melanin was found to significantly (P0.001) inhibit apoptosis induced by 64 hemagglutination unit influenza virus infection with a inhibitory rate comparable to that obtained by virazole and showed no cytotoxicity. The inital results suggested that the mechanism of melanin against the apoptosis induced by influenza virus was related to the blockage of viruses' adsorbtion to the host cells.