Gerson S. Paiva

Evaluation of Antioxidant and Antiangiogenic Properties of Caesalpinia Echinata Extracts

Natural products contain important combinations of ingredients, which may to some extent help to modulate the effects produced by oxidation substrates in biological systems. It is known that substances capable of modulating the action of these oxidants on tissue may be important allies in the control of neovascularization in pathological processes. The aim of this study was to evaluate the antioxidant and antiangiogenic properties of an ethanol extract of Caesalpinia echinata. The evaluation of antioxidant properties was tested using two methods (DPPH inhibition and sequestration of nitric oxide). The antiangiogenic properties were evaluated using the inflammatory angiogenesis model in the corneas of rats. The extract of C. echinata demonstrated a high capacity to inhibit free radicals, with IC50 equal to 42.404 µg/mL for the DPPH test and 234.2 µg/mL for nitric oxide. Moreover, it showed itself capable of inhibiting the inflammatory angiogenic response by 77.49%. These data suggest that biochemical components belonging to the extract of C. echinata interfere in mechanisms that control the angiogenic process, mediated by substrates belonging to the arachidonic acid cascade, although the data described above also suggest that the NO buffer may contribute to some extent to the reduction in the angiogenic response.

Antineoplasic Effect of Aqueous Extract of Plectranthus Amboinicus in Ehrlich Ascites Carcinoma

There are 46,000 new cases of peritoneal carcinomatosis per year in the USA and 17,700 in Brazil. New media, including plant derivatives, are being tested in its treatment. Plectranthus amboinicus is a medicinal plant widely used in Brazil, especially in the northeast region, for the treatment of various diseases, including cancer. This present study evaluates the intraperitoneal use of aqueous extracts of Plectranthus amboinicus (AEPa) at a dose of 200 mg / kg for the treatment of the ascitic form of Ehrlich carcinoma. It is concluded also the AEPa produced antineoplastic effect in ascitic form of Ehrlich carcinoma.

A Comparative Study of the effects of Vitamins C and E in the Development of Sarcoma 180 in Mice

In this work we have investigated the effects of vitamins C and E on tumors via the mice xenotransplant model of sarcoma 180 (S180) in vivo. The experimental results suggest that dosages of 100 mg/kg vitamin C and 400 mg/kg vitamin E yields a great inhibitory behavior on tumors.