HIV-1 infection inhibition by neem (<em>Azadirachta indica</em> A. Juss.) leaf extracts and Azadirachtin

Abstract

Mexico is a country with a strong attachment to the using of traditional medicine, which is heritage of pre hispanic ethnic groups of Mexican territory that are still present all across the country. The Mexican markets, dedicated exclusively to trade medicinal plants, have facilitated the using, getting and importation of plants from other regions of the world such as neem, which has been used for many health conditions, both non- communicable and infectious diseases, such as cancer, diabetes, bacterial, parasitic and viral infections, even the infection with human immunodeficiency virus. So that, the objective of this study was to evaluate HIV-1 infection inhibition by neem leaf extracts and neem compounds. Cytotoxicity of aqueous and ethanolic neem leaf extracts and Azadirachtin and Limonene compounds was evaluated in CEM T-cells at concentrations of 1 ppm, 10 ppm (extracts); 1 &mu;M, 10 &mu;M (compounds). Only the aqueous extract concentration of 1 ppm and Azadirachtin at 1 &mu;M and 10 &mu;M concentrations allowed a cell viability of 100 % compared with controls p &gt; 0.05. Based on the results of cytotoxicity we proceeded to evaluate the HIV infection inhibition with the aqueous extract at concentration of 1 ppm and Azadirachtin at both concentrations. Inhibition percentages greater than 50 % were obtained and showed to be significant compared to controls p &lt; 0.001 This work evidenced the HIV infection inhibition by aqueous neem leaf extracts and Azadirachtin; even though, the antiretroviral mechanism is not completely understood. Furthermore, more studies need to be conducted in order to identify the active compound responsible for the anti HIV activity described in the aqueous extract.