Moringa Oleifera Lam Leaves Extract and Its Compounds Effect on The Intracellular Calcium Release in Human Aortic Smooth Muscle Cells

Moringa oleifera leaves have been scientifically shown lower blood pressure but the mechanism of action on this is achieved has not been fully explored. Intracellular calcium release is a fundamental cellular process linked to vascular function and modulation of this process can have significant implications for cardiovascular health. The blocking effects of calcium influx and release by Moringa oleifera Lam leaf extract and its compounds on the human aortic smooth muscle cells (HAoSMCs) were studied. The cell viability assay was carried out to determine the concentrations of M. oleifera Lam leaf extract and its compounds for the assay. Test compounds (amlodipine, chlorogenic acid, gallic acid, kaempferol, M. oleifera leaf extract, quercetin and vicenin-2) were incubated with Quin-2-AM in the presence and absence of extracellular calcium (Ca2+) and with the addition of caffeine and potassium (K+) in HAoSMCs. Following treatments with the test compounds, the influx of extracellular Ca2+ into the cytosol of HAoSMCs was significantly inhibited (p <0.001). The test compounds significantly (p <0.001) decreased the concentration of cytosolic Ca2+ induced by K+ depolarisation. The test compounds also significantly (p <0.001) affected the intracellular Ca2+metabolism, regulated by the caffeine-sensitive storage site in HAoSMCs. No synergistic effect on the decreasing of cytosolic Ca2+ level was observed when the test compounds were used in combination with amlodipine. M. oleifera Lam leaf extract and its compounds may act as Ca2+channel blockers (CCBs) and there is also a possibility of interactions between the test compounds and amlodipine.