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

Clinics (Sao Paulo). 2015 Nov;70(11):751-7. doi: 10.6061/clinics/2015(11)07.

Abstract

Objectives: This 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.

Results: Nigella 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antihypertensive Agents / administration & dosage
  • Antihypertensive Agents / pharmacology*
  • Blood Pressure / drug effects*
  • Heme Oxygenase (Decyclizing) / metabolism
  • Hypertension / chemically induced
  • Hypertension / drug therapy*
  • Male
  • Malondialdehyde / analysis
  • Models, Animal
  • NADPH Oxidases / metabolism
  • NG-Nitroarginine Methyl Ester
  • Nicardipine / administration & dosage
  • Nicardipine / pharmacology
  • Nigella sativa / chemistry*
  • Nitric Oxide / blood
  • Oxidative Stress / drug effects
  • Peptidyl-Dipeptidase A / metabolism
  • Plant Oils / pharmacology*
  • Rats, Sprague-Dawley

Substances

  • Antihypertensive Agents
  • Plant Oils
  • Nitric Oxide
  • Malondialdehyde
  • Nicardipine
  • Heme Oxygenase (Decyclizing)
  • NADPH Oxidases
  • Peptidyl-Dipeptidase A
  • NG-Nitroarginine Methyl Ester