Resveratrol May Have Anti-flu Activity

Tue May 24, 2005 11:29 AM ET

NEW YORK (Reuters Health) - Resveratrol, a chemical found in red grapes, blocks replication of the influenza virus in cell culture and in animals, Italian researchers report.

"Resveratrol merits further investigation as a potential weapon for combating the growing threat of influenza," Dr. Anna Teresa Palamara of the Institute of Microbiology in Rome and colleagues conclude.

In cell culture experiments, resveratrol prevented influenza from replicating.

Resveratrol treatment had the greatest effect when administered 3 hours after exposure to influenza. Smaller but significant effects were seen when treatment began 6 hours after infection, but at 9 hours after infection resveratrol treatment had no effect. Pre-treatment also did not change susceptibility to infection.

Studies in a mouse model of influenza showed that injections of resveratrol after inoculation of influenza increased survival by 40% compared with placebo injections. The amount of virus present in the lung 6 days after infection was 98% lower in the resveratrol-treated mice.

Resveratrol 's anti-influenza activity seems to center on its ability to interfere with key "host-cell functions" that are essential for virus replication, the authors explain in The Journal of Infectious Diseases.

SOURCE: Journal of Infectious Diseases May 15, 2005.