Efeito da fração hidro-metanólica de Sabicea brasiliensis Wernh sobre as atividades ectonucleotidases em células musculares lisas vasculares

Abstract

Cardiovascular diseases are the largest cause of death worldwide, and arterial hypertension is an important risk factor. Any change in the diameter of blood vessels may cause changes in blood pressure. Sabicea brasiliensis Wernh, commonly known as "blood of Christ", is popularly used to control blood pressure. Purinergic signalling modulates vasorelaxation and vasoconstriction processes by the availability of nucleotides, which undergo hydrolysis by ectonucleotidases. We thus evaluated the potential of hydro-methanolic (HM) fraction of the roots of S. brasiliensis on the activity of ectonucleotidases in vascular smooth muscle cells A7r5. Cell viability was determined at treatment periods 24, 48 and 72h by the MTT assay at different concentrations of HM fraction 62.5; 125; 250 and 500 μg·mL-1 and ectonucleotidase activities were evaluated by colorimetric method incubating their substrates after 48 hours of treatment with HM at the same concentrations. Results show that none of HM tested concentrations were cytotoxic on A7r5 cells at all periods analyzed. However, the fraction influenced the proliferation of A7r5 after 48 hours, showing new possibilities of study. Also, despite one could observe a tendency in inhibit phosphodiesterase (E-NPP) activity, there was no significant change (p ˂ 0.05) in the hydrolysis of all substrates tested. It is known that the roots of S. brasiliensis present a high antioxidant potential, which could impact the activities of ectonucleotidases. In this sense, additional experiments are needed to clarify the modulation of ectonucleotidases by HM fraction, which could, at least in part, elucidate the antihypertensive effect of the plant.