Nigella sativa oil attenuates inflammation and oxidative stress in experimental myocardial infarction

Background A growing interest in using Nigella sativa oil (NSO) in the prevention or treatment of several cardiovascular diseases has prompted this study. The research aims to investigate the effect of NSO on cardiac damage prevention after long-term administration in induced myocardial infarction (MI) in rats. Methods NSO was analyzed for its fatty acids composition using gas chromatography-mass spectrometry (GC-MS) analysis and administered in rats before and after isoproterenol (45 mg/kg body weight) induced myocardial infarction. The following parameters were assessed: electrocardiograms, histopathological examination, serum biochemical aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase-myocardial band (CK-MB), serum and heart inflammation (tumor necrosis factor-alpha (TNF), interleukin 1 beta (IL-1b), and interleukin 6 (IL-6)), and tissue oxidative stress (total antioxidant capacity (TAC), total oxidative stress (TOS), nitric oxide (NO), malondialdehyde (MDA), and the total thiols (THIOL)). Results Linoleic acid (C18:2n-6) and oleic acid (C18:1n-9) were approximately 89% of total fatty acids while palmitic acid (C16:0) was 6.10%. Administration of NSO for 28 days helped in preventing QT and QTc interval prolongation and reduced heart rate (HR), after MI induction. The histological assessment showed improvement in myofibrillary degeneration and necrosis and also better reduced inflammatory process in the groups treated with NSO. In serum, pro-inflammatory cytokines IL-1b and IL-6 were downregulated in chronic conditions (for IL-1b, NSO vs. control was 86.09vs 150.39 pg/mL, and for IL-6 NSO vs. control was 78.00 vs. 184.98 pg/ml). In the heart tissue, the downregulation was observed only for TNF in both acute and chronic conditions (acute NSO vs. control was 132.37 vs. 207.63 pg/mL, and chronic NSO vs. control was 135.83 vs. 183.29 pg/ml). The pro-oxidant parameters TOS, NO, MDA, and OSI, were reduced in the groups treated with NSO only after 14 days of treatment, suggesting that the NSO antioxidant effect is time-dependent. Conclusions NSO administration might have a favourable impact on the regulation of oxidative stress and inflammation processes after MI induction in rats, and it is worth considering its administration as an adjuvant treatment.