Herbal standardized for the treatment of chronic diseases: Evaluation of mutagenic and estrogenic activities and in vitro bioavailabity

Abstract

Plants are an important source of biologically active natural products, many of which are used as models for the synthesis of a large number of drugs. These natural products show an almost inexhaustible range of diversity in structure and physicochemical and biological properties. However, out of an estimated 250,000 species of higher plants in the world, only 10% have been investigated biologically. Thus, would be lightly relevant to assess the mutagenic and estrogenic activities and bioavailability in vitro of standardized extracts from native plants. These extracts form part of the project Biota-FAPESP (Proc. Nº. 09/52237-9), under the coordination of Prof. Dr. Wagner Vilegas. To assess mutagenicity, the S. typhimurium reverse mutation assay (Ames test) with strains TA98, TA97, TA100 and TA102 will be employed, both with and without metabolic activation. It is required by Brazilian law that, prior to its registration, a potential herbal medicine should be tested for mutagenic activity. Estrogenic activity will be estimated in recombinant yeast the experimental model (RYA), in view of growing evidence that some compounds known as endocrine disruptors can mimic or antagonize the action of steroid hormones. In addition, the in vitro bioavailability of the extracts studied will be assayed in colon carcinoma (Caco-2) cell cultures, since the extracts show have promising activities against certain chronic diseases that pose a serious problem in public health system. These studies will contribute to clarifying the mechanisms by which these extracts act in the assessed activities, and throw light on their safety and efficacy before they can be widely used for the benefit of human health.