piperine and Hypertension

The herbal formula (Sahatsatara, STF), the Thai traditional poly-herbal recipe, has been used for treatment of muscle pain, anti-flatulence and numbness on hands and feet, with the caution when used in hypertensive patients. However, there is no scientific evidence to prove its effects on cardiovascular system. Piperine is the proposed major active compound in STF. It is shown to have antihypertensive effect in the L-NAME-induced endothelial dysfunction rats.. This study investigated the pharmacokinetics, mechanism of action, as well as the hemodynamic and vasoactive effect and toxicity of STF and piperine using spontaneously hypertensive rats (SHR) and normal Wistar rats (NWR).. The amount of piperine in STF was measured by ultra performance liquid chromatography (UPLC). SHR and NWR were gavaged with piperine (50mg/kg/day) or STF (100, 300, or 1000mg/kg/day) alone or together with L-NAME (in drinking water) for 28 days. Hemodynamic effects were monitored by noninvasive tail cuff every 7 days. Vasorelaxation effect on the thoracic aorta in organ chamber was observed through force transducer at the end of the experiment. Biochemical parameters for kidney and liver toxicity were measured. In addition, pharmacokinetic study was performed using non-compartment analysis.. The amount of piperine in STF was 1.29%w/w. Both STF and piperine did not affect blood pressure and heart rate in both SHR and NWR. Interestingly, STF and piperine increased acetylcholine-induced vasorelaxation of isolated thoracic aorta and have vascoluprotective effect in nitric oxide (NO) impaired rats. No liver or kidney toxicity was found in this study. Non-compartment pharmacokinetic analysis showed that the time to reach maximum concentration (T. STF had no effect on blood pressure in both SHR and NWR. However, it was able to relax isolated thoracic aorta and had the potential for vasculoprotective effect in hypertensive and NO impaired condition. The effects of STF were comparable to those of piperine.

Topics: Alkaloids; Animals; Antihypertensive Agents; Benzodioxoles; Blood Pressure; Hypertension; Male; Phytotherapy; Piperidines; Plant Extracts; Plants, Medicinal; Polyunsaturated Alkamides; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Rats, Wistar; Thailand; Vasodilation

The presented study is aimed on exploring the effects of black pepper on blood pressure in the rat model of experimental hypertension induced by chronic NO synthesis inhibition.. Piperine, the compound of black pepper, can cause a significant decrease of blood pressure in normotensive rats possibly via calcium channel blockade, a pathway that is known to be effective in prevention of L-NAME (N(G)-nitro-L-arginine methyl ester) induced hypertension.. Wistar rats were administered clear water (C), L-NAME (40 mg/kg/day, L), piperine (20 mg/kg/day) in corn oil by oral gavage with L-NAME (LP) or without it (P) for 6 weeks. The systolic blood pressure was measured weekly. Specimens of thoracic aorta were processed in paraffin and histological slices were stained with hematoxylin and eosin, Mallory's phosphotungstic acid hematoxylin (PTAH), orcein, antibodies against inducible NO synthase (iNOS) and smooth muscle cells actin (SMCA). Microscopic pictures were digitally processed and morphometrically evaluated.. L-NAME increased the blood pressure, cross-sectional area of aorta, media thickness, elastin and SMCA synthesis and PTAH positive myofibrils relative and absolute content in the aortic media, wheras it decreased percentual content of iNOS, elastin and SMCA. Piperine decreased the blood pressure rise from the third week of treatment, synthesis of elastin and the percentual and absolute content of PTAH positive myofibrils, however, it did not affect other parameters.. Oral administration of piperine is able to partially prevent the increase of blood pressure caused by chronic L-NAME administration. This effect is probably caused by the blockage of voltage-dependent calcium channels and supported by filamentous actin disassembly (Tab. 1, Fig. 2, Ref. 35).

Topics: Alkaloids; Animals; Antibodies; Aorta, Thoracic; Benzodioxoles; Blood Pressure; Elastin; Hypertension; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Piper nigrum; Piperidines; Polyunsaturated Alkamides; Rats; Rats, Wistar