Estudos fitoquímicos e avaliação da atividade antitumoral de extratos vegetais de Casearia sylvestris nanoencapsulados

Abstract

The term cancer refers to neoplasias that are characterized by uncontrolled growth of cells that have some kind of genetic mutation. Prostate cancer is the cancer with the highest incidence in men. In its initial phase, the prostate cancer is hormone dependent, so current therapy is based on blocking the biosynthesis of hormones, but after the initial treatment, neoplastic cells grow back inordinately becoming resistant to treatment. Although there are drugs in clinical trials, it´s still necessary the search for molecules that exhibit activity against prostate cancer cells. Natural products have a great importance in cancer treatment. Due to its past history of beneficial effects on human health and especially its cytotoxic activity on cancer cells, the plant Casearia sylvestris was studied. However, the insolubility and low bioavailability in aqueous media hamper the use of these compounds. In an attempt to reduce this limitation, nanostructured systems for drug delivery have been recognized as promising vehicles. Polymeric nanoparticles have been used to overcome problems of solubility, bioavailability and aiming the target cells (tumor). The purpose of this work was the preparation of formulations of polymeric nanoparticles containing plant extract of C. sylvestris and evaluation of cytotoxic activity in cell lines and healthy prostate carcinoma. Thus, 3 factorial 22 designs were developed, and parameters as solution stability, recovery and encapsulation efficiency were considered. The nanoparticles were prepared by the method of nanoprecipitation, and the stability, recovery and encapsulation efficiency were satisfactory. In biological tests, the nanoparticles formulations showed selectivity up to 23 % on healthy and neoplastic cells, decreasing the viability of prostate carcinoma cells by 45%. Therefore, plant extracts of C. sylvestris shown to be active in cancer cells, and polymeric nanoparticle delivery systems may be promising in the treatment of prostate carcinoma.