Mechanisms of the antihypertensive effects of Nigella sativa oil in L-NAME-induced hypertensive rats

Abstract

OBJECTIVESThis study was conducted to determine whether the blood pressure-lowering effect of Nigella sativa might be mediated by its effects on nitric oxide, angiotensin-converting enzyme, heme oxygenase and oxidative stress markers.METHODS:Twenty-four adult male Sprague-Dawley rats were divided equally into 4 groups. One group served as the control (group 1), whereas the other three groups (groups 2-4) were administered L-NAME (25 mg/kg, intraperitoneally). Groups 3 and 4 were given oral nicardipine daily at a dose of 3 mg/kg and Nigella sativa oil at a dose of 2.5 mg/kg for 8 weeks, respectively, concomitantly with L-NAME administration.RESULTSNigella sativa oil prevented the increase in systolic blood pressure in the L-NAME-treated rats. The blood pressure reduction was associated with a reduction in cardiac lipid peroxidation product, NADPH oxidase, angiotensin-converting enzyme activity and plasma nitric oxide, as well as with an increase in heme oxygenase-1 activity in the heart. The effects of Nigella sativa on blood pressure, lipid peroxidation product, nicotinamide adenine dinucleotide phosphate oxidase and angiotensin-converting enzyme were similar to those of nicardipine. In contrast, L-NAME had opposite effects on lipid peroxidation, angiotensin-converting enzyme and NO.CONCLUSION:The antihypertensive effect of Nigella sativa oil appears to be mediated by a reduction in cardiac oxidative stress and angiotensin-converting enzyme activity, an increase in cardiac heme oxygenase-1 activity and a prevention of plasma nitric oxide loss. Thus, Nigella sativa oil might be beneficial for controlling hypertension.

Purification of angiotensin‐converting enzyme from human plasma and investigation of the effect of some active ingredients isolated from Nigella sativa L. extract on the enzyme activity

“…Also, it has been observed that N. sativa seeds applied to hypertensive rats are partially diuretic and hypotensive (Zaoui et al, 2000). Jaarin et al (2015) reported that N. sativa oil reduced the increase in systolic blood pressure in rats treated with L-NGnitroarginine methyl ester (L-NAME). Jaarin et al (2015) reported that N. sativa oil reduced the increase in systolic blood pressure in rats treated with L-NGnitroarginine methyl ester (L-NAME).…”

“…In addition, in patients with metabolic syndrome, N. sativa oil was found to be antihypertensive (Najmi, Nasiruddin, Khan, & Haque, 2013). Jaarin et al (2015) reported that N. sativa oil reduced the increase in systolic blood pressure in rats treated with L-NGnitroarginine methyl ester (L-NAME). This oil decreased cardiac oxidative stress and ACE activity, displayed an increase in cardiac heme oxygenase-1 activity and a prevention of plasma nitric oxide loss activity in rats.…”

Effects of hydrogen sulphide on oxidative stress, inflammatory cytokines, and vascular remodelling in l‐NAME‐induced hypertension

“…l ‐NAME powder (Sigma‐Aldrich) was dissolved in saline (0.9%) and administrated intraperitoneally (IP) at a dose of 25 mg/kg/d . Jaarin et al reported that l ‐NAME, a competitive inhibitor of NOS, was able to induce hypertension at this dose. Sodium hydrosulphide (NaHS), a H 2 S donor, was purchased from Acros Organics, and was freshly dissolved in saline (0.9%).…”

Effect of DPP-4 inhibitor sitagliptin against ischemia-reperfusion (I/R) injury in hyperlipidemic animals

“…The Control (Saline) and Sitg (50 mg) animal groups received the same daily oral treatment as in Experiment 1, while the other two groups were co-treated intraperitoneally (i.p.) with the NOS inhibitor (L-NAME, 25 mg/kg/day) (Jaarin et al 2015), three hours' post-oral administration of Sitg (50 mg) and its vehicle (saline). At the end of the treatment, the same anesthetization procedure, whole-heart preparation process, and I/R injury protocol (10 min perfusion, 45 min prolonged regional ischemia and 120 min reperfusion, ex vivo), coronary artery re-ligation, and tissue staining procedure were carried out as in Experiment 1 (Fig.…”