The effect of Nigella sativa oil on vascular dysfunction assessed by flow‐mediated dilation and vascular‐related biomarkers in subject with cardiovascular disease risk factors: A randomized controlled trial

Abstract

Cardiovascular diseases (CVD) are the leading causes of mortality worldwide. Flowmediated dilation (FMD) is a marker of vascular function. Beneficial cardiometabolic effects of Nigella sativa (N. sativa) have been observed. We evaluated the effect of N. sativa oil on FMD, plasma nitrite, and nitrate (NOx) as nitric oxide (NO) metabolites, and inflammatory markers in subjects with CVD risk factors. Fifty participants were randomly assigned to either the N. sativa (two capsules of 500 mg N. sativa oil) or the placebo group (two capsules of 500 mg mineral oil), for 2 months.The brachial FMD, plasma NOx, vascular cellular adhesion molecule-1 (VCAM-1), and intracellular adhesion molecule-1 (ICAM-1) were measured. FMD and plasma NOx levels was significantly increased in the N. sativa group compared to the placebo group (changes: 2.97 ± 2.11% vs. 0.71 ± 3.19%, p < 0.001 for FMD and 4.73 ± 7.25 μmol/L vs. 0.99 ± 5.37 μmol/L, p = 0.036 for plasma NOx). However, there was no significant difference in ICAM-1 and VCAM-1 levels between groups. Therefore, N. sativa oil improves vascular NO and FMD in subjects with cardiovascular risk factors. However, more studies are warranted to confirm the beneficial impacts of the N. sativa oil on vascular inflammation.

Endothelial Function Responses to Nigella sativa (Black Seed) Supplementation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

“…The populations studied within the three RCTs included patients with coronary artery disease (CAD) in two trials [ 15 , 16 ] and patients with Hashimoto's thyroiditis in one [ 14 ]. Included patients were predominantly having hypertension (HTN), diabetes mellitus (DM), dyslipidemia, and smoking status.…”

“…The form and dosage of NS varied. Emamat et al [ 16 ] used two capsules of 500 mg each, Tavakoli-Rouzbehani et al [ 15 ] used 2 gm of NS oil, and Farhangi and Tajmiri [ 14 ] used 2 gm of NS powder. The duration of follow-up was almost two months across the included studies.…”

“…For example, Tavakoli-Rouzbehani et al showed a significant reduction in the levels of ICAM and VCAM after administrating NS [ 15 ]. However, Emamat et al, showed that the effect of NS and placebo on ICAM and VCAM was comparable, with no statistically significant difference [ 16 ]. Therefore, in this systematic review and meta-analysis, we aimed to evaluate the endothelial function responses of ICAM and VCAM to NS (black seed) supplementation.…”

Effect of Nigella sativa on Selected Gastrointestinal Diseases

“…Other key phytonutrients of nigella are sterols (β-sitosterol, stigmasterol, campesterol, 5-avenasterol) and saponins (e.g., triterpenes-alpha-hederin), phenolic compounds, and alkaloids. Nigella seeds contain isoquinoline alkaloids (nigellicymine and nigellicymine N-oxide), diterpene alkaloids (nigellamine), and indazole alkaloids (nigellidine and nigellicin) [ 5 ]. Depending on the variety, Nigella sativa contains (on a dry matter basis) water (3.8–7.0%), proteins (18.59–31.2%), fats (22.0–56.4%), carbohydrates (24.9–40%), dietary fiber (3.7–4.7%), both soluble (20.5–27.1 g/100 g) and insoluble fractions (6.5–8.9 g/100 g), fat-soluble vitamins (mainly α-, β- and γ-tocopherols), water-soluble vitamins (B1, B3, B6, B9), and minerals (potassium, iron, calcium, zinc, phosphorus, magnesium, copper) [ 18 ].…”

“…By modulating the profile of inflammatory cytokines, NS shows antioxidant activity, even in chronic inflammatory conditions. It displays a wide spectrum of actions, for example, protective effects in cardiovascular diseases, i.e., high blood pressure, and showing hypolipidemic effects [ 4 , 5 , 6 ]. It has a positive effect in metabolic diseases, such as diabetes and obesity, and in various types of cancer, such as multiple myeloma and lymphoma [ 7 , 8 , 9 , 10 , 11 ].…”