Advances of research on anti-HIV agents from traditional Chinese herbs.

The current approach for dealing with the global pandemic of AIDS focuses on pharmaceuticals. The classic treatment of AIDS is highly active antiretroviral therapy, but most people living with HIV/AIDS-especially those in developing countries-have little or no access to the treatment because of the high cost of the therapy. Such treatment is associated with toxic side effects and drug resistance. As such, the search for better anti-HIV agents continues, with much attention focused on natural sources-particularly, plant species. Thousands of herbs have been screened for anti-HIV activity, and new compounds have been discovered from the extracts, many of which demonstrate inhibitory activity against HIV. Their mechanisms of action include inhibiting the activities of reverse transcriptase, protease, and integrase; weakening infection at the level of viral entry; and downregulating related gene expression. This provides researchers with new clues to synthesize drugs for the anti-HIV battle. Some synthetic derivatives of the anti-HIV natural products have stronger inhibitory effects in vitro than do their natural counterparts. Various mixed preparations of these anti-HIV herbs are in clinical trials or are applied in the treatment of people living with HIV/AIDS-some of which yield lower plasma viral load, enhance immune function, relieve related symptoms and signs, improve the quality of life, or, in combination with highly active antiretroviral therapy, alleviate the side effects of biomedical drugs. This article reviews current laboratory findings and clinical trials of anti-HIV agents from traditional herbs-particularly, herbs in traditional Chinese medicine. Drug interactions with highly active antiretroviral therapy and criteria for clinical evaluation of traditional Chinese medicine treatment are also discussed.