The vascular endothelium plays a pivotal role in the maintenance of vascular homeostasis, mediated by vasoactive molecules produced by endothelial cells. The balance between vasoconstrictor and vasodilator biomolecules is what guarantees this equilibrium. Therefore, an increase in the bioavailability of vasoconstrictors along with a reduction in vasodilators may indicate a condition known as endothelial dysfunction. Endothelial dysfunction is marked by an inflammatory process and reduced activity of vasoprotective enzymes, being characterized by some factors like the reduction of the bioavailability of nitric oxide (NO) and increase in the production of reactive oxygen species (ROS), pro-inflammatory and vasoconstrictor molecules. This condition is a predictive marker of several cardiovascular diseases (e.g., atherosclerosis, hypertension, and diabetes). Research is affected by the scarcity of suitable in vitro models that simulate endothelial dysfunction. The goal of this study was to induce an in vitro condition to mimic endothelial dysfunction by inhibiting NO synthesis in cells. Thymus-derived endothelial cells (tEnd.1) were treated with different concentrations of L-NAME (from 1 to 1,000 μM) for different times (12, 24, 48, 72, 96, and 120 h without and with retreatment every 24 h). Cell viability, nitrite concentration, p22phox, NOX2, NOX4, IL-6, and ACE genes expression and lipid peroxidation were evaluated. The results indicate that the treatment with 100 μM L-NAME for 72 h without retreatment reduced NO concentration and NOX4 gene expression while increasing ACE expression, thus mimicking reduced vascular protection and possibly increased vasoconstriction. On the other hand, treatment with 100 μM L-NAME for 96 h with retreatment reduced the concentration of NO and the expression of the p22phox gene while increasing the expression of the IL-6 and ACE genes, mimicking the increase in inflammation and vasoconstriction parameters. Based on these results, we thus propose that both 100 μM L-NAME for 72 h without retreatment and 100 μM L-NAME for 96 h with retreatment may be used as models for in vitro endothelial dysfunction according to the purpose of the study to be conducted.

Arterial hypertension is a worldwide public health problem and the search for new medicines is one of the biggest challenges for the treatment of this pathology. Secondary metabolites of plants exhibit pharmacological properties of great phyto therapeutic interest. Cerrado is one of the largest biomes in Brazil and research with Cerrado plants as therapeutic resources is of growing interest. Our objective was to compile data regarding the Cerrado plants that already have some of their active compounds described and may potentially be used to treat arterial hypertension. We concluded that flavonoids, tannins, steroids and saponins exhibit important properties to low blood pressure. Thus, the species from Cerrado Brazilian such as pau-paraíba (Simarouba versicolor), pau-santo (Kielmeyera coriacea), abiu-do-cerrado (Pouteria torta), guarandi (Calophyllum brasiliense), bacaba (Oenocarpus bacaba), puçá-amarelo (Mouriri elliptica), fava-de-anta (Dimorphandramollis), murici (Byrsonima crassifolia) and cereja-do-cerrado (Eugenia calycina) are strong candidates for future herbal studies in this field.

Aims: Study addressed the antioxidant activity (AA) of Sabicea brasiliensis roots crude extract (CE), ethyl acetate (EAF), and hydro-methanolic (HMF) fractions, and its impact on cell viability and adenine nucleotide hydrolysis in vascular A7r5 cells. Materials and Methods: AA of CE, EAF and HMF were determined by the inhibition of the DPPH and ABTS radicals. Total phenolic content was evaluated by Folin-Ciocalteau. Cell viability was determined by MTT assay at different concentrations (62.5; 125; 250 and 500 μg·mL-1) of EAF and HMF after 24, 48 and 72 h. Ectonucleotidase activities were evaluated by colorimetric methods after 48 h EAF or HMF treatment. Results: The highest AA was observed for CE (76%), followed by EAF (46%) and HMF (23%). Phenolic content followed the same pattern. After 48 h, EAF increased A7r5 vascular cells viability by 40%, 40%, 62% and 25% at distinct concentrations, respectively; while HMF augmented it by 50% (500 μg·mL−1). Finally, after 48 h EAF (500 μg·mL−1) decreased about 50% of ATP and ADP metabolism while HMF inhibited 56 and 59% the hydrolysis of NPP substrate (at 125 and 250 μg·mL−1). Conclusion: Study confirmed the high AA of S. brasiliensis, which influences vascular cells proliferation and purines metabolism, pointing to potential cellular pathways that may support the popular use of this plant.

No abstract