Vascular Reactivity Concerning Orthosiphon stamineus Benth-Mediated Antihypertensive in Aortic Rings of Spontaneously Hypertensive Rats

The potential effect of natural antioxidants on endothelial dysfunction associated with arterial hypertension

Arterial hypertension represents a leading cause of cardiovascular morbidity and mortality worldwide, and the identification of effective solutions for treating the early stages of elevated blood pressure (BP) is still a relevant issue for cardiovascular risk prevention. The pathophysiological basis for the occurrence of elevated BP and the onset of arterial hypertension have been widely studied in recent years. In addition, consistent progress in the development of novel, powerful, antihypertensive drugs and their appropriate applications in controlling BP have increased our potential for successfully managing disease states characterized by abnormal blood pressure. However, the mechanisms responsible for the disruption of endogenous mechanisms contributing to the maintenance of BP within a normal range are yet to be fully clarified. Recently, evidence has shown that several natural antioxidants containing active ingredients originating from natural plant extracts, used alone or in combination, may represent a valid solution for counteracting the development of arterial hypertension. In particular, there is evidence to show that natural antioxidants may enhance the viability of endothelial cells undergoing oxidative damage, an effect that could play a crucial role in the pathophysiological events accompanying the early stages of arterial hypertension. The present review aims to reassess the role of oxidative stress on endothelial dysfunction in the onset and progression of arterial hypertension and that of natural antioxidants in covering several unmet needs in the treatment of such diseases.

Sinensetin: An Insight on Its Pharmacological Activities, Mechanisms of Action and Toxicity

Sinensetin, a plant-derived polymethoxylated flavonoid found in Orthosiphon aristatus var. aristatus and several citrus fruits, has been found to possess strong anticancer activities and a variety of other pharmacological benefits and promising potency in intended activities with minimal toxicity. This review aims to compile an up-to-date reports of published scientific information on sinensetin pharmacological activities, mechanisms of action and toxicity. The present findings about the compound are critically analyzed and its prospect as a lead molecule for drug discovery is highlighted. The databases employed for data collection are mainly through Google Scholar, PubMed, Scopus and Science Direct. In-vitro and in-vivo studies showed that sinensetin possessed strong anticancer activities and a wide range of pharmacological activities such as anti-inflammatory, antioxidant, antimicrobial, anti-obesity, anti-dementia and vasorelaxant activities. The studies provided some insights on its several mechanisms of action in cancer and other disease states. However, more detail mechanistic studies are needed to understand its pharmacological effects. More in vivo studies in various animal models including toxicity, pharmacokinetic, pharmacodynamic and bioavailability studies are required to assess its efficacy and safety before submission to clinical studies. In this review, an insight on sinensetin pharmacological activities and mechanisms of action serves as a useful resource for a more thorough and comprehensive understanding of sinensetin as a potential lead candidate for drug discovery.

Randomised, double-blind, placebo-controlled, assessment of the efficacy and safety of dietary supplements in prehypertension

We aimed to evaluate efficacy and tolerability of a protocol including lifestyle modifications and a novel combination of dietary supplements in prehypertension. A prospective, double-blind, randomised, placebo-controlled trial was conducted in 176 subjects (103 men, aged 52±10 years), with blood pressure (BP) of 130-139 mm Hg systolic and/or 85-89 mm Hg diastolic entered. After a single-blind run-in period, participants were randomised to twice daily placebo (n=88) or a commercially available combination pill (n=88). Primary endpoints were the differences in clinic BP between the two groups at the end of the trial. Secondary endpoints included intragroup differences in clinic BP during the study period and response rates (that is, BP <130/85 mm Hg or a BP reduction >5 mm Hg on week 12). Baseline characteristics were similar among the treatment groups. At 12 weeks, the supplement group had lower systolic BP (124±9 versus 132±7 mm Hg, P<0.0001) and similar diastolic BP (81±8 versus 82±7 mm Hg, P=0.382) compared to the placebo group. With respect to baseline measures, changes in BP with supplements were statistically significant for systolic (-9.3±4.2 mm Hg, P<0.0001) and diastolic values (-4.2±3.6 mm Hg, P<0.0001). Changes versus baseline in systolic and diastolic BP, conversely, were not different on placebo. The overall response rate at week 12 was significantly greater with supplements than placebo (58% (51 of 88) and 25% (22 of 88), respectively, P<0.0001). This randomised trial shows that combination of supplements with BP-lowering effect is an effective additional treatment to conventional lifestyle modifications for a better control of systolic BP in prehypertension.