Fixed oil of Nigella sativa and derived thymoquinone inhibit eicosanoid generation in leukocytes and membrane lipid peroxidation

Evaluation of Antioxidant and Antibacterial Potentials of Nigella sativa L. Suspension Cultures under Elicitation

Nigella sativa L. (family Ranunculaceae) is an annual herb of immense medicinal properties because of its major active components (i.e., thymoquinone (TQ), thymohydroquinone (THQ), and thymol (THY)). Plant tissue culture techniques like elicitation, Agrobacterium mediated transformation, hairy root culture, and so on, are applied for substantial metabolite production. This study enumerates the antibacterial and antioxidant potentials of N. sativa epicotyl suspension cultures under biotic and abiotic elicitation along with concentration optimization of the elicitors for enhanced TQ and THY production. Cultures under different concentrations of pectin and manganese chloride (MnCl₂) elicitation (i.e., 5 mg/L, 10 mg/L, and 15 mg/L) showed that the control, MnCl₂ 10 mg/L, and pectin 15 mg/L suspension extracts greatly inhibited the growth of E. coli, S. typhimurium, and S. aureus (MIC against E. coli, i.e., 2.35 ± 0.8, 2.4 ± 0.2, and 2.46 ± 0.5, resp.). Elicitation decreased SOD enzyme activity whereas CAT enzyme activity increased remarkably under MnCl₂ elicitation. MnCl₂ 10 mg/L and pectin 15 mg/L elicitation enhanced the DPPH radical inhibition ability, but ferric scavenging activity was comparable to the control. TQ and THY were quantified by LC-MS/MS in the cultures with high bioactive properties revealing maximum content under MnCl₂ 10 mg/L elicitation. Therefore, MnCl₂ elicitation can be undertaken on large scale for sustainable metabolite production.

Neuroprotective Effects of Mitochondria-Targeted Plastoquinone and Thymoquinone in a Rat Model of Brain Ischemia/Reperfusion Injury

We explored the neuroprotective properties of natural plant-derived antioxidants plastoquinone and thymoquinone (2-demethylplastoquinone derivative) modified to be specifically accumulated in mitochondria. The modification was performed through chemical conjugation of the quinones with penetrating cations: Rhodamine 19 or tetraphenylphosphonium. Neuroprotective properties were evaluated in a model of middle cerebral artery occlusion. We demonstrate that the mitochondria-targeted compounds, introduced immediately after reperfusion, possess various neuroprotective potencies as judged by the lower brain damage and higher neurological status. Plastoquinone derivatives conjugated with rhodamine were the most efficient, and the least efficiency was shown by antioxidants conjugated with tetraphenylphosphonium. Antioxidants were administered intraperitoneally or intranasally with the latter demonstrating a high level of penetration into the brain tissue. The therapeutic effects of both ways of administration were similar. Long-term administration of antioxidants in low doses reduced the neurological deficit, but had no effect on the volume of brain damage. At present, cationic decylrhodamine derivatives of plastoquinone appear to be the most promising anti-ischemic mitochondria-targeted drugs of the quinone family. We suggest these antioxidants could be potentially used for a stroke treatment.

Effects of Thymoquinone on the Pharmacokinetics and Pharmacodynamics of Glibenclamide in a Rat Model

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively ( P<0.05). The AUC and T1/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.

Biochemical, Histopathological and Immunohistochemical Evaluation of the Protective and Therapeutic Effects of Thymoquinone against Ischemia and Ischemia/Reperfusion Injury in the Rat Ovary

AIM

To evaluate the antioxidant effects of thymoquinone (TQ) and to investigate the biochemical, histopathological and immunohistochemical changes in experimental rat ovarian torsion.

METHODS

A total of 48 female adult rats were used in this study and randomly divided into 7 groups: (1) sham operation; (2) bilateral 3-hour ovarian ischemia; (3) 3-hour ischemia and 3-hour reperfusion; (4) and (5) rats were administered 20 and 40 mg/kg of TQ, respectively, before 0.5 h of ischemia, and then 3 h of ovarian ischemia was applied; (6) and (7) 3-hour ovarian ischemia was applied; 2.5 h after the induction of ischemia, rats were administered the same doses of TQ; at the end of 3 h of ischemia, a 3-hour reperfusion was applied. Histologic changes under light microscopy, immunoreactivity for anticaspase-3 and serum levels of malondialdehyde, interleukin-6, catalase and glutathione peroxidase were noted and compared between the 7 groups.

RESULTS

Ischemia and ischemia/reperfusion cause a deterioration of biochemical and histopathological parameters. Administration of TQ seems to reverse these alterations and alleviate the injury. Antioxidant defense mechanisms appear to be enhanced by the administration of TQ.

CONCLUSION

TQ at different doses attenuates ovarian ischemia and ischemia/reperfusion injury in rats.

Immunomodulatory and anti-inflammatory action of Nigella sativa and thymoquinone: A comprehensive review

Many herbal products are now used as remedies to treat various infectious and non-infectious conditions. Even though the use of herbs and natural products is much more evident in the Eastern world, their use in Western cultures is continuously increasing. Although the immunomodulatory effects of some herbs have been extensively studied, research related to possible immunomodulatory effects of many herbs and various spices is relatively scarce. Here, we provide a comprehensive review of the immunomodulatory and anti-inflammatory properties of Nigella sativa, also known as black seed or black cumin, and its major active ingredient, thymoquinone (TQ). This review article focuses on analyzing in vitro and in vivo experimental findings that were reported with regard to the ability of N. sativa and TQ to modulate inflammation, cellular and humoral adaptive immune responses, and Th1/Th2 paradigm. The reported capability of N. sativa to augment the cytotoxic activity of natural killer (NK) cells against cancer cells is also emphasized. The molecular and cellular mechanisms underlying such immunomodulatory and anti-inflammatory effects of N. sativa and TQ are highlighted. Moreover, the signal transduction pathways implicated in the immunoregulatory functions of N. sativa and TQ are underscored. Experimental evidence suggests that N. sativa extracts and TQ can potentially be employed in the development of effective therapeutic agents towards the regulation of immune reactions implicated in various infectious and non-infectious conditions including different types of allergy, autoimmunity, and cancer.

Cytotoxic and antioxidant properties of phenolic compounds from Tagetes patula flower

CONTEXT

Tagetes patula Linn. (Asteraceae) (French Marigold) flowers are used by local practitioners for cancer treatment; however, it lacks scientific justification.

OBJECTIVE

Identification of bioactive compounds in T. patula flower for cytotoxic and growth inhibition in human cancer cell lines along with its antioxidant properties using chemical and cell based systems.

MATERIALS AND METHODS

The T. patula flower methanol extract, its seven fractions, and three phenolic compounds including methyl protocatechuate (1), patuletin (2), and patulitrin (3) were evaluated using sulforhodamine-B assay against HeLa, HT-144, NCI-H460, MCF-7, PC-3, and SF-268 human cancer cell lines. In parallel, antioxidant activity was evaluated using chemical (DPPH(·), deoxyribose, and lipid peroxidation assays) and cell-based chemiluminescence systems (human neutrophils and mice macrophages).

RESULTS

The methanol extract and ethyl acetate insoluble fraction exhibited cytotoxic and growth inhibitory effects against HeLa in which 2 exhibited highest cell growth inhibition (GI50: 0.6 ± 0.1 µg/ml) and cytotoxicity (LC50: 2.5 ± 0.1 µg/ml). It also scavenged LOO(·) (IC50: 6.5 ± 0.7 µg/ml) and [Formula: see text] (IC50: 27.5 ± 1.3 μg/ml) in chemical systems and human neutrophils, respectively. However, 1 preferably scavenged H2O2-Cl(-) (IC50: 0.5 ± 0.01 μg/ml) in mice macrophages.

DISCUSSION AND CONCLUSION

Compound 2 from T. patula flower exhibited both growth inhibitory and cytotoxic properties while 1 and 3 were only growth inhibitory against HeLa. 1-3 also displayed antioxidant properties implying its probable role in growth inhibition/cytotoxic action. The present study provides scientific evidence for the use of T. patula flower in cancer treatment by traditional healer.

Evaluation of the protective effect of Nigella sativa extract and its primary active component thymoquinone against DMBA-induced breast cancer in female rats

INTRODUCTION

The historical use of black cumin seed (Nigella sativa) dates back centuries, being embedded in Arabian culture and having a long history of unsurpassed medicinal value with versatility to treat a wide range of ailments. Thymoquinone (TQ) is now known to be the primary active constituent of black cumin seed oil (BCS oil) responsible for its medicinal effects and also showing promise for treatment of cancer.

MATERIAL AND METHODS

In the current study, we have studied the effects of TQ and BCS oil on tumor markers (MDA, LDH, ALP and AST), histopathological alterations and the regulation of several genes (Brca1, Brca2, Id-1 and P53 mutation) related to breast cancer in female rats induced by 7,12-dimethylbenz[a]anthracene (DMBA) treatment. Rats received a single dose (65 mg/kg b.w.) of DMBA via an intragastric tube to induce breast cancer. Animals that received DMBA were treated orally with 1, 5, 10 mg/kg of TQ or BCS oil via an intragastric tube three times per week for 4 months.

RESULTS

We found that TQ and then BCS reduced the rate of tumor markers (levels of MDA and LDH as well as ALP and AST activities), inhibited the histopathological alterations and decreased the expression of the Brca1, Brca2, Id-1 and P53 mutations in mammary tissues of female rats induced by DMBA treatment.

CONCLUSIONS

The results suggest that TQ and BCS oil exert a protective effect against breast carcinogens. The antioxidant property of TQ and BCS oil is mediated by their actions and investigating other underlying mechanisms merits further studies.

Volatile compounds and antioxidant capacity of the bio-oil obtained by pyrolysis of Japanese red pine (pinus densiflora siebold and zucc.)

In the present study, sawdust bio-oil (SBO) manufactured by fast pyrolysis of Japanese red pine (Pinus densiflora Siebold and Zucc.) sawdust was analyzed for its volatile chemical compound composition and evaluated for its free radical scavenging potential, inhibition of lipid peroxidation and reducing power. Gas chromatography and mass spectroscopy revealed 29 volatile compounds, comprising 97.6% of the total volatile compounds in SBO. The antioxidant potential of SBO in terms of IC₅₀ values was 48.44 µg/mL for hydroxyl radical scavenging, 89.52 µg/mL for 1,1-diphenyl-2-picrylhydraxyl radical scavenging, 94.23 µg/mL for 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulphonic acid] radical scavenging, and 136.06 µg/mL for superoxide radical scavenging activity. The total phenol content in SBO was 5.7% gallic acid equivalent. Based on the composition of its volatile compounds, high free radical scavenging potential and antioxidant properties, SBO could be used as a source of antioxidant compounds, flavoring agents and nutraceuticals in the food, pharmaceutical, and cosmetic industries.

Biomarker responses in earthworms (Eisenia fetida) to soils contaminated with di-n-butyl phthalates

Di-n-butyl phthalates (DBP) are recognized as ubiquitous contaminants in soil and adversely impact the health of organisms. Changes in the activity of antioxidant enzymes and levels of glutathione-S-transferase (GST), glutathione (GSH), and malondialdehyde (MDA) were used as biomarkers to evaluate the impact of DBP on earthworms (Eisenia fetida) after exposure to DBP for 28 days. DBP was added to artificial soil in the amounts of 0, 5, 10, 50, and 100 mg kg(-1) of soil. Earthworm tissues exposed to each treatment were collected on the 7th, 14th, 21st, and 28th day of the treatment. We found that superoxide dismutase (SOD) and catalase (CAT) levels were significantly inhibited in the 100 mg kg(-1) treatment group on day 28. After 21 days of treatment, GST activity in 10-50 mg kg(-1) treatment groups was markedly stimulated compared to the control group. MDA content in treatment groups was higher than in the control group throughout the exposure time, suggesting that DBP may lead to lipid peroxidation (LPO) in cells. GSH content increased in the treatment group that received 50 mg kg(-1) DBP from 7 days of exposure to 28 days. These results suggest that DBP induces serious oxidative damage on earthworms and induce the formation of reactive oxygen species (ROS) in earthworms. However, DBP concentration in current agricultural soil in China will not constitute any threat to the earthworm or other animals in the soil.

Mitochondria-targeted antioxidant SkQT1 decreases trauma-induced neurological deficit in rat and prevents amyloid-β-induced impairment of long-term potentiation in rat hippocampal slices

This study assesses a protective effect of a mitochondria-targeted antioxidant SkQT1 (a mixture of 10-(6'-toluquinonyl) decyltriphenylphosphonium and 10-(5'-toluquinonyl) decyltriphenylphosphonium in proportion of 1.4:1), using an open focal trauma model of the rat brain sensorimotor cortex and a model of amyloid-beta1-42 (Abeta)-induced impairment of hippocampal long-term potentiation (LTP), a kind of synaptic plasticity associated with learning and memory. It was found that a trauma-induced neurological deficit could be partially improved with daily intraperitoneal injections of SkQT1 (250 nmol/kg) for 5 days after the trauma. Neither an analog of SkQT1 without thymoquinone (C12TPP) nor original thymoquinone without a cation residue was effective to improve such conditions. In the SkQ molecule, the phosphonium cation can be replaced by the rhodamine 19 cation, with the SkQTR1 being still active in the treatment of the neurological deficit. Application of 200 nM Abeta to rat hippocampal slices impaired the induction of LTP in the hippocampal CA1 pyramidal layer. A single intraperitoneal injection of SkQT1 (250 nmol/kg body weight) made 24 h before the slice preparation prevented the harmful effect of Abeta on the LTP. Thus mitochondria-targeted antioxidants, containing thymoquinone, have neuroprotective properties.

Anti-diabetic activity of different oils through their effect on arylsulfatases

BACKGROUND

Diabetes mellitus (DM) is characterized by the overproduction of the reactive oxygen species which affects the integrity of the lysosomal membrane affecting lysosomal enzymes. The effect of these species is blocked by some natural products as antioxidants. In the current study, groups of normal and streptozotocin (STZ)-induced diabetic rats were treated by Nigella sativa (NS), olive and canola oils and subjected to the study of arylsulfatases as a model of lysosomal enzymes. The aim of the present study is to investigate the effect of STZ-induced diabetes on arylsulfatases in presence and absence of NS, olive and canola oils.

METHODS

Different groups of rats were induced by STZ, treated with different oils and compared to their corresponding control group. All groups were subjected for the assays of blood glucose, insulin, catalase and arylsulfatases. A comparative kinetic study of arylsulfatses was performed to detect the alteration of catalytic characterization.

RESULTS

The results demonstrated that diabetes causes a significant elevation in the level of hepatic arylsulfatase B and a significant reduction of hepatic catalase as an antioxidant enzyme. NS and olive oils returned catalase and arylsulfatase B activities back near to normal by fixing their catalytic properties. Furthermore, the maximum velocity of arylsulfatases A and B was significantly elevated in the induced diabetes, whereas their Km values were significantly changed. The treatment of diabetic rats by NS and olive oils reduced the degree of significance.

CONCLUSION

Diabetes induces significant alterations of the catalytic characters of arylsulfatases and some oils decrease this alteration through an antioxidant-mediated effect.

Elucidation of molecular targets of bioactive principles of black cumin relevant to its anti-tumour functionality - An Insilico target fishing approach

Black cumin (Nigella sativa) is a spice having medicinal properties with pungent and bitter odour. It is used since thousands of years to treat various ailments, including cancer mainly in South Asia and Middle Eastern regions. Substantial evidence in multiple research studies emphasizes about the therapeutic importance of bioactive principles of N. sativa in cancer bioassays; however, the exact mechanism of their anti-tumour action is still to be fully comprehended. The current study makes an attempt in this direction by exploiting the advancements in the Insilico reverse screening technology. In this study, three different Insilico Reverse Screening approaches have been employed for identifying the putative molecular targets of the bioactive principles in Black cumin (thymoquinone, alpha-hederin, dithymoquinone and thymohydroquinone) relevant to its anti-tumour functionality. The identified set of putative targets is further compared with the existing set of experimentally validated targets, so as to estimate the performance of insilico platforms. Subsequently, molecular docking simulations studies were performed to elucidate the molecular interactions between the bioactive compounds & their respective identified targets. The molecular interactions of one such target identified i.e. VEGF2 along with thymoquinone depicted one H-bond formed at the catalytic site. The molecular targets identified in this study need further confirmatory tests on cancer bioassays, in order to justify the research findings from Insilico platforms. This study has brought to light the effectiveness of usage of Insilico Reverse Screening protocols to characterise the un-identified target-ome of poly pharmacological bioactive agents in spices.

Thymoquinone attenuates toxicity and oxidative stress induced by bisphenol A in liver of male rats

Bisphenol A (BPA) is a fairly ubiquitous compound which has a great concern to human health. The current study was designed to (1) Assess the adverse effect of oral administration of BPA on liver of male rats and (2) Evaluate the role of thymoquinone (TQ), the major bioactive ingredient in the oil of Nigella sativa seed, in alleviating the possible detrimental effects of BPA on the liver. Rats were divided into control group administered olive oil, BPA group administered 10 mg BPA kg(-1) day(-1), TQ group administered 10 mg TQ kg(-1) day(-1) and BPA-TQ group administered the same previous doses of both BPA and TQ. After 24 h of the last dose, rats were decapitated and blood and liver were collected to determine some oxidative stress and biochemical parameters. Bisphenol A elicited a significant elevation in lipid peroxidation concomitant with depletion of antioxidant defense system in hepatic tissue. It also induced liver dysfunction as indicated by altered liver function markers and biochemical parameters. The administration of TQ attenuated the BPA-induced oxidative stress, alleviated the antioxidative system and improved to a large extent the liver functioning. This data clearly indicates that TQ has the potential to be a protective agent against oxidative stress and liver injury.

Panacea seed "Nigella": A review focusing on regenerative effects for gastric ailments

Nigella sativa (NS) or black cumin is a dark, thin, and crescent-shaped, seeded shrub belonging to the Ranunculaceae family commonly growing on Mediterranean coasts in Saudi Arabia, northern Africa and Asia. They have amazing curative and therapeutic features that make them one of the most popular, safe, non-detrimental, and cytoprotective medicinal plant that can be used for prevention and treatment of many complicated diseases. Originally, N. sativa was used to treat migraines and allergy, and researches have shown its effectiveness in destroying cancer cells as well. The gastro protective effect of NS oil and its constituents has also been reported earlier; however, the complete perception on etiology and pathogenesis of gastric ulcer is not yet clear. Herein, we attempt to unveil some of the potential mechanisms exhibited by NS in preventing problems related to gastric ulcers. Gastric ailments like ulcers and tumors are the most common disorders of the gastro-intestinal tract in the present day life of the industrialized world. Gastric ulcer being a multifaceted problem exhibits complex etiology and is the fourth most common cause of cancer mortality. Drug interactions and toxicity are the main hindrances in chemotherapy. The existing merits and demerits of modern-day drugs make us turn toward the plant kingdom which may provide a valuable resource of novel potent natural compounds for pharmaceuticals or alternately, as dietary supplements. In this context, the revered phytotherapeutic N. sativa comes as a promising savior in today’s times. This review aims to summarize, both the functional and disease-related effects in the area of gastroenterology.

Antioxidant, lipid peroxidation inhibition and free radical scavenging efficacy of a diterpenoid compound sugiol isolated from Metasequoia glyptostroboides

OBJECTIVE

To investigate the antioxidant efficacy of a biologically active diterpenoid compound sugiol isolated from Metasequoia glyptostroboides (M. glyptostroboides) in various antioxidant models.

METHODS

An abietane type diterpenoid sugiol, isolated from ethyl acetate extract of M. glyptostroboides cones, was analyzed for its antioxidant efficacy as reducing power ability and lipid peroxidation inhibition as well as its ability to scavenge free radicals such as 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl radicals.

RESULTS

The sugiol showed significant and concentration-dependent antioxidant and free radical scavenging activities. Consequently, the sugiol exerted lipid peroxidation inhibitory effect by 76.5% as compared to α-tocopherol (80.13%) and butylated hydroxyanisole (76.59%). In addition, the sugiol had significant scavenging activities of 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl free radicals in a concentration-dependent manner by 78.83%, 72.42%, 72.99% and 85.04%, when compared to the standard compound ascorbic acid (81.69%, 74.62%, 73.00% and 73.79%) and α-tocopherol/butylated hydroxyanisole (84.09%, 78.61%, 74.45% and 70.02%), respectively.

CONCLUSIONS

These findings justify the biological and traditional uses of M. glyptostroboides or its secondary metabolites as confirmed by its promising antioxidant efficacy.

Induction of apolipoprotein A-I gene expression by black seed (Nigella sativa) extracts

CONTEXT

Black seed [Nigella sativa L. (Ranunculaceae)] has been shown in animal models to lower serum cholesterol levels.

OBJECTIVES

In order to determine if extracts from black seed have any effects on high-density lipoprotein (HDL), we characterized the effects of black seed extract on apolipoprotein A-I (apo A-I) gene expression, the primary protein component of HDL.

MATERIALS AND METHODS

Hepatocytes (HepG2) and intestinal cells (Caco-2) were treated with black seed extracts, and Apo A-I, peroxisome proliferator-activated receptor α (PPARα), and retinoid-x-receptor α (RXRα) were measured by Western blot analysis. Apo A-I mRNA levels were measured by quantitative real-time polymerase chain reaction and apo A-I gene transcription was measured by transient transfection of apo A-I reporter plasmids.

RESULTS

Extracts from black seeds significantly increased hepatic and intestinal apo A-I secretion, as well as apo A-I mRNA and gene promoter activity. This effect required a PPARα binding site in the apo A-I gene promoter. Treatment of the extract with either heat or trypsin had no effect on its ability to induce apo A-I secretion. Treatment with black seed extract induced PPARα expression 9-fold and RXRα expression 2.5-fold. Furthermore, the addition of PPARα siRNA but not a control siRNA prevented some but not all the positive effects of black seed on apo A-I secretion.

DISCUSSION

Black seed extract is a potent inducer of apo A-I gene expression, presumably by enhancing PPARα/RXRα expression.

CONCLUSIONS

We conclude that black seed may have beneficial effects in treating dyslipidemia and coronary heart disease.

Advances in the development of novel antioxidant therapies as an approach for fetal alcohol syndrome prevention

Ethanol is the most common human teratogen, and its consumption during pregnancy can produce a wide range of abnormalities in infants known as fetal alcohol spectrum disorder (FASD). The major characteristics of FASD can be divided into: (i) growth retardation, (ii) craniofacial abnormalities, and (iii) central nervous system (CNS) dysfunction. FASD is the most common cause of nongenetic mental retardation in Western countries. Although the underlying molecular mechanisms of ethanol neurotoxicity are not completely determined, the induction of oxidative stress is believed to be one central process linked to the development of the disease. Currently, there is no known effective strategy for prevention (other than alcohol avoidance) or treatment. In the present review we will provide the state of art in the evidence for the use of antioxidants as a potential therapeutic strategy for the treatment using whole-embryo and culture cells models of FASD. We conclude that the imbalance of the intracellular redox state contributes to the pathogenesis observed in FASD models, and we suggest that antioxidant therapy can be considered a new efficient strategy to mitigate the effects of prenatal ethanol exposure.

Thymoquinone attenuates cisplatin-induced hepatotoxicity via nuclear factor kappa-β

Background

Cisplatin (CP) is known as a potent anti-cancer drug. The most therapeutic adverse effect of CP is induced hepatotoxicity. In the present study, the protective effect of thymoquinone (TQ) on CP-induced hepatotoxicity was studied.

Methods

Wistar rats were divided into three groups (15 rats each). Group 1 served as the control group. Group 2 rats were injected ip with a single dose of CP (12 mg/kg b.w, i.p.). Group 3 rats were orally pre-treated with TQ (500 mg. kg⁻¹. day⁻¹) for one month, then the animals were injected i.p with CP 12 mg.kg⁻¹.

Results

The beneficial effects of TQ with its antioxidant/anti-inflammatory effects were observed. Injection of rats with CP markedly affected the liver functions and histopathological changes. The antioxidant enzyme activities and reduced glutathione (GSH) contents were significantly decreased while the levels of malondialdehyde (MDA) significantly increased. The electromobility shift assay (EMSA) showed a significant activation of NF-κB-p65 in the rat liver injected with CP. Furthermore, the expression and concentrations of inflammatory tumor necrosis factor (TNF-α), nitric oxide synthetase (iNOS), and interleukin (IL-1β) were markedly elevated in the CP injected rats. The administration of TQ improved all the altered functions, histopathology of the liver and attenuated the activated NF-κB. The antioxidant enzyme activities (glutathione peroxidase and glutathione –S transferase) of the rat livers were markedly increased while MDA was reduced as a result of TQ administration. In addition, the expression of TNF-α, iNOS, and IL-1β were markedly reduced.

Conclusion

It was concluded that, TQ has potential benefits in the prevention of the onset and progression of CP induced hepatotoxicity.

The effect of nutritional supplements on serum high-density lipoprotein cholesterol and apolipoprotein A-I

One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol. Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). Diet has an important role in modulating HDL cholesterol level. The widespread use of nutritional supplements may also alter the biology of HDL. In this review, we discuss the effect of select nutritional supplements on serum HDL cholesterol and apo A-I levels. Some nutritional supplements, such as phytosterols, soy proteins, and black seed extracts, may increase HDL cholesterol levels, while others such as cholic acid and high doses of commonly used antioxidant vitamins may downregulate HDL cholesterol levels and reduce its cardioprotection. Multiple mechanisms are involved in the regulation of HDL levels, so changes in production and clearance of HDL may have different clinical implications. The clinical relevance of the changes in HDL and apo A-I caused by nutrient supplementation needs to be tested in controlled clinical trials.

Protective role of thymoquinone against liver damage induced by tamoxifen in female rats

One of the major reasons for terminating a clinical trial is the liver toxicity induced by chemotherapy. Tamoxifen (TAM) is an anti-estrogen used in the treatment and prevention of hormone-dependent breast cancer. Tamoxifen therapy may cause hepatic injury. The seeds of Nigella sativa, which contain the active ingredient thymoquinone (TQ), have been used in folk medicine for diverse ailments. TQ is reported to possess anticancer and hepatoprotective effects. In this study, the protective effects of TQ against TAM-induced hepatotoxicity in female rats were evaluated. Four groups of rats were used: control; TAM; TQ; TAM+TQ. TAM (45 mg·(kg body mass)(-1)·day(-1), by intraperitoneal injection (i.p.), for 10 consecutive days) resulted in elevated serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, total bilirubin, and gamma glutamyl transferase, as well as depletion of reduced glutathione in the liver and accumulation of lipid peroxides. Also, TAM treatment inhibited the hepatic activity of superoxide dismutase. Further, it raised the levels of tumor necrosis factor alpha in the liver and induced histopathological changes. Pretreatment with TQ (50 mg·(kg body mass)(-1)·day(-1); orally, for 20 consecutive days, starting 10 days before TAM injection) significantly prevented the elevation in serum activity of the assessed enzymes. TQ significantly inhibited TAM-induced hepatic GSH depletion and LPO accumulation. Consistently, TQ normalized the activity of SOD, inhibited the rise in TNF-α and ameliorated the histopathological changes. In conclusion, TQ protects against TAM-induced hepatotoxicity.

Nigella sativa Pretreatment in Guinea Pigs Exposed to Cigarette Smoke Modulates In Vitro Tracheal Responsiveness

BACKGROUND

In previous studies, the bronchodilator and antitussive effects of Nigella sativa have been demonstrated on guinea pigs.

OBJECTIVES

In the present study, the effect of the hydroethanolic extract of N. sativa on tracheal responsiveness in guinea pigs exposed to cigarette smoke was examined.

MATERIALS AND METHODS

Three groups of guinea pig models of COPD were given drinking water alone (COPD group), drinking water containing vitamin C (COPD + VC group), and N. sativa (COPD + NS group). Tracheal responses to methacholine were measured as effective concentration causing 50% of maximum response (EC50 M) in control animals (group C) and three groups of guinea pigs with COPD (n = 7, for all groups). Tracheal responses to 0.1% ovalbumin in comparison to contraction obtained by 10 µM methacholine were also examined.

RESULTS

The tracheal responsiveness to both methacholine and ovalbumin in guinea pigs with COPD were significantly higher than those of controls (P < 0.001 for both cases). The tracheal responsiveness in the COPD + VC and the COPD + NS groups to both methacholine and ovalbumin were significantly decreased in comparison to the COPD group (P < 0.05 and P < 0.001, respectively).

CONCLUSIONS

These results showed the preventive effect of hydroethanolic extract of N. sativa on tracheal responsiveness of guinea pig model of COPD, which was as effective as vitamin C.

Mitigating role of thymoquinone rich fractions from Nigella sativa oil and its constituents, thymoquinone and limonene on lipidemic-oxidative injury in rats

Therapeutic role of Nigella sativa (NS) seed oil fractions, methanolic extract (ME) and volatile oil (VO) and their constituents, thymoquinone (TQ) and limonene (LMN) in relation to lipidemic-oxidative stress in Wistar rats was determined. The total phenolic contents of NS seed oil and their ME and VO extracts were 320.00 ± 3.00, 300.12 ± 0.04 and 288.41 ± 0.01 mg gallic acid equivalents per 100 g of NS oil, respectively. Their Fe(+2) chelating activities were 870.00 ± 2.00, 222.31 ± 5.80 and 38.59 ± 1.43 mg EDTA equivalents per 100 g of NS oil, respectively. These fractions and compounds exhibited strong antioxidant activities against 2,2-diphenyl-1-picryl hydrazyl, 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid, nitric oxide and hydroxyl radicals. Potential antiperoxidative effects of these fractions and compounds were also observed in liposome, and lipidemic-induced lipid peroxidation in atherogenic suspension fed rats, pretreated with 100 mg ME, 20 mg VO, 10 mg pure TQ or 200 mg LMN for 30 days. ME containing ω-6 linoleic acid and palmitic acid natural compounds was highly effective against lipidemic oxidative stress than VO extract possessing thymol and isothymol phenolic natural antioxidant compounds. TQ, principal compound shared to both the extracts. The test fractions and compounds effectively reduced the erythrocyte and liver lipid peroxidation markers, conjugated diene, lipid hydroperoxide and malondialdehyde to near normal levels in the order ME > TQ > VO > LMN, by directly counteracting free radicals as well as suppressing hepatic HMG-CoA reductase activity. Our findings demonstrated that these natural products, preferably ME possess significant antioxidant activities, and may be recommended as new potential sources of natural antioxidants.

Stable isotope dilution gas chromatography-mass spectrometry for quantification of thymoquinone in black cumin seed oil

Black cumin seed (Nigella sativa L.) is a widely used spice and herb, where thymoquinone (2-isopropyl-5-methyl-1,4-benzoquinone) is the major bioactive compound. Here, a stable isotope dilution (SID) gas chromatography-mass spectrometry (GC-MS) technique was developed for the quantification of thymoquinone. A doubly deuterated thymoquinone ([(2)H2]-thymoquinone) was synthesized for the first time with more than 93% deuteration degree shown by mass spectrometry and proton nuclear magnetic resonance ((1)H NMR). This compound was used as an internal standard for the quantification of thymoquinone using a SID GC-MS method. The validation experiment showed a recovery rate of 99.1 ± 1.1% relative standard deviation (RSD). Standard addition and external calibration methods have also been used to quantify thymoquinone, which cross-validated the developed stable isotope dilution assay (SIDA). In comparison to external calibration and standard addition methods, the SIDA method is robust and accurate. The concentration of thymoquinone in five marketed black cumin seed oils ranged between 3.34 and 10.8 mg/mL by use of SID GC-MS.

The effect of single dose of thymoquinone, the main constituents of Nigella sativa, in guinea pig model of asthma

Introduction: In previous studies, the relaxant and antihistaminic effects of thymoquinone, the main constituents of Nigella sativa, have been demonstrated on guinea pig tracheal chains. In the present study, the prophylactic effect of (IP) single dose of thymoquinone on tracheal responsiveness and lung inflammation of guinea pig model of asthma was examined.

Methods: Thirty guinea pigs were randomly divided to 3 groups; control (C), sensitized (S) and pretreated group with (TQ); 3 mg/kg, IP (S+TQ). Tracheal responsiveness to methacholine and ovalbumin (OA), total and differential cell count in bronchoalveolar lavage, lung pathological changes and blood Interleukin 4(IL-4) and Interferon gamma (IFNγ) level in three groups were measured.

Results: Increased tracheal responsiveness to methacholine and OA, lung lavage fluid white blood cell (WBC) and eosinophil count, IL-4 and IFN-γ levels and pathological changes were seen in sensitized group in comparison to control group (p<0.001 to p<0.05). Decreased tracheal responsiveness to methacholine and OA, pathological changes and bronchoalveolar lavage eosinophil were observed in S+TQ group compared to S group (p<0.001 to p<0.05). However, tracheal responsiveness to methacholine and OA, contractility, bronchoalveolar lavage WBC and eosinophil and most of pathological changes in S+TQ group were significantly higher than those in controls (p<0.01 to p<0.05).

Conclusion: These results showed the preventive effect of single dose of thymoquinone on guinea pig model of asthma.

Intraperitoneal Nigella sativa for prevention of postoperative intra-abdominal adhesions in rats

OBJECTIVE

To evaluate intraperitoneal administration of Nigella sativa (NS) to prevent postoperative intraperitoneal adhesion (PPA) after surgical manipulation of rat uterine horn.

MATERIALS AND METHODS

Two forms of NS were used in the study (Volatile oil (NSVO) and the ethanolic extract (NSEE)). A total of 50 rats were randomly assigned to the sham group (n = 10), control group (n = 10), NSVO group (n = 10), NSEE group (n = 10), and the Seprafilm group(n = 10). After 14 days, rats were sacrificed. Adhesions were examined macroscopically, and degree of adhesions was scored. A part of horn was excised, and superoxide dismutase (SOD) and glutathione peroxidase activities as well as malondialdehyde levels were evaluated, and histological score was calculated.

RESULTS

Total microscopic score of the NSEE group was significantly lower than the control group (p = .001) and was marginally significantly lower than the seprafilm group (p = .005). Collagen formation score was higher in the seprafilm group compared to the sham and NSEE groups (p < 0.001, p = .003, respectively). Apoptotic cells were lower in the NSEE group compared to the control group (p = .003) and also lower in the NSEE and NSVO groups compared to the seprafilm group (p = .001, p < .001, respectively). Only SOD activity was higher in the NSVO and seprafilm groups compared to the control group (p < .001).

CONCLUSION

NSEE form seems to have a possible effect in the prevention of PPAs. This may occur by its effect in decreasing collagen formation and by decreasing apoptosis in the injured tissues. NSVO form seems to induce SOD. Therefore, combined use of NSVO with seprafilm may increase the adhesion preventive effect of seprafilm.

Effects of Nigella sativa L. seed oil on abnormal semen quality in infertile men: a randomized, double-blind, placebo-controlled clinical trial

In recent years, wide utilization of herbal drugs has encouraged scientists to determine their impressive effects on health. Since Nigella sativa L. seed (N. sativa) has many uses including infertility in traditional medicine, the effects of Nigella sativa L. seed oil on abnormal semen quality in infertile men with abnormal semen quality are of interest. This study was conducted on Iranian infertile men with inclusion criteria of abnormal sperm morphology less than 30% or sperm counts below 20×10(6)/ml or type A and B motility less than 25% and 50% respectively. The patients in N. sativa oil group (n=34) received 2.5mlN. sativa oil and placebo group (n=34) received 2.5ml liquid paraffin two times a day orally for 2 months. At baseline and after 2 months, the sperm count, motility and morphology and semen volume, pH and round cells as primary outcomes were determined in both groups. Results showed that sperm count, motility and morphology and semen volume, pH and round cells were improved significantly in N. sativa oil treated group compared with placebo group after 2 months. It is concluded that daily intake of 5ml N. sativa oil for two months improves abnormal semen quality in infertile men without any adverse effects.

Anti-ulcer activity of essential oil constituents

Essential oils have attracted considerable worldwide attention over the last few decades. These natural products have wide-ranging pharmacological activities and biotechnological applications. Faced with the need to find new anti-ulcer agents and the great effort on the development of drugs for the treatment of ulcers, in this review, the anti-ulcer activities of 21 bioactive compounds found in essential oils are discussed.

Effect of Thymoquinone on Oxidative Stress in Escherichia coli-Induced Pyelonephritis in Rats

BACKGROUND

Recurrent urinary tract infections are important in children and adults with diabetes mellitus and/or incontinence due to risk of pyelonephritis (PYN) and renal damage. There is a positive correlation released free radicals during PYN and renal damage. Experimental studies showed that antioxidant agents improve renal damage when used immediately after bacterial inoculation.

OBJECTIVE

The aim of the present study was to evaluate whether treatment by thymoquinone (TQ) before or during Escherichia coli inoculation prevents oxidative damage in acute pyelonephritis (PYN) in an ascending obstructive rat model.

METHODS

In this study, 42 Wistar rats were grouped as follows: control, PYN (24, 48, and 72 hours), and TQ-PYN (24, 48, and 72 hours). E. coli (1 ×10(9) colony forming units) was inoculated into the bladder via urethral catheterization in both the PYN and TQ groups. TQ injections were performed 24 hours before bacteria inoculation and repeated at 24-hour intervals during the indicated time at a dose of 10 mg/kg body weight intraperitoneally in TQ groups.

RESULTS

Superoxide dismutase activity was statistically lower in the TQ-PYN-48 and -72 groups than the PYN-48 and -72 groups (P < 0.001, P = 0.004, respectively). Catalase activity was significantly higher in PYN-24, -48, and -72 groups than the control group (P < 0.001). In addition, there was a significant difference between the TQ-PYN-24, -48, and -72 groups and PYN groups in terms of glutathione peroxidase activity (P < 0.001, P = 0.026, P = 0.046, respectively). When the TQ-PYN-72 group was compared with the PYN-72 group, malondialdehyde levels were significantly lower in the TQ-PYN-72 group than in the PYN-72 group (P = 0.033). A histologic examination also confirmed the protective effect of TQ. In statistical analysis of histopathologic findings, there were significant differences between the PYN-24 and TQ-PYN-24, PYN-48 and TQ-PYN-48, and PYN-72 and TQ-PYN-72 groups (P = 0.008, P < 0.001, P < 0.001, respectively).

CONCLUSIONS

The results indicate that TQ administration attenuated the oxidative damage that occurred in PYN and, therefore, could be used as a supportive agent to protect the kidneys from oxidative damage caused by PYN.

Effects of selected bioactive natural products on the vascular endothelium

The endothelium, a highly active structure, regulates vascular homeostasis through the release of numerous vasoactive factors that control vascular tone and vascular smooth cell proliferation. A larger number of medicinal plants and their isolated chemical constituents have been shown to beneficially affect the endothelium. For example, flavonoids in black tea, green tea, and concord grape cause a vasodilation possibly through their antioxidant properties. Allicin, a by-product of the enzyme alliinase, has been proposed to be the main active metabolite and responsible for most of the biological activities of garlic, including a dose-dependent dilation on the isolated coronaries. Thymoquinone, the principal phytochemical compound found in the volatile oil of the black seed, and the hawthorn extract have also been shown to improve aging-related impairment of endothelium-dependent relaxations in animal models. In this review, the effect of some of the natural products, including Camellia sinensis (black tea and green tea), Vitis labrusca (concord grape), Allium sativum (garlic), and Nigella sativa (black seed) and Crataegus ssp (hawthorn extract), is explored. The molecular mechanisms behind these potential therapeutic effects are also discussed.

Thymoquinone, a bioactive component of black caraway seeds, causes G1 phase cell cycle arrest and apoptosis in triple-negative breast cancer cells with mutant p53

Thymoquinone (TQ) from black caraway seeds has several anticancer activities; however, its effect on triple-negative breast cancer (TNBC) cells that lack functional tumor suppressor p53 is not known. Here, we explored the growth inhibitory effect of TQ on 2 TNBC cell lines with mutant p53. Cell metabolism assays showed that TQ inhibited TNBC cell growth without affecting normal cell growth. Flow cytometric analyses of TQ-treated TNBC cells showed G1 phase cell cycle arrest and apoptosis characterized by the loss of mitochondrial membrane integrity. Western blots of lysates from TQ-treated TNBC cells showed cytochrome c and apoptosis-inducing factor in the cytoplasm, as well as caspase-9 activation consistent with the mitochondrial pathway of apoptosis. Caspase-8 was also activated in TQ-treated TNBC cells, although the mechanism of activation is not clear at this time. Importantly, TQ-induced apoptosis was only partially inhibited by zVAD-fmk, indicating a role for caspase-independent effector molecules. Poly(ADP-ribose) polymerase cleavage and increased γH2AX, as well as reduced Akt phosphorylation and decreased expression of X-linked inhibitor of apoptosis, were evident in TQ-treated cells. Finally, TQ enhanced cisplatin- and docetaxel-induced cytotoxicity. These findings suggest that TQ could be useful in the management of TNBC, even when functional p53 is absent.

Composition, in vitro antioxidant and antimicrobial activities of essential oil and oleoresins obtained from black cumin seeds (Nigella sativa L.)

Gas chromatography-mass spectrometry (GC-MS) analysis revealed the major components in black cumin essential oils which were thymoquinone (37.6%) followed by p-cymene (31.2%), α-thujene (5.6%), thymohydroquinone (3.4%), and longifolene (2.0%), whereas the oleoresins extracted in different solvents contain linoleic acid as a major component. The antioxidant activity of essential oil and oleoresins was evaluated against linseed oil system at 200 ppm concentration by peroxide value, thiobarbituric acid value, ferric thiocyanate, ferrous ion chelating activity, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging methods. The essential oil and ethyl acetate oleoresin were found to be better than synthetic antioxidants. The total phenol contents (gallic acid equivalents, mg GAE per g) in black cumin essential oil, ethyl acetate, ethanol, and n-hexane oleoresins were calculated as 11.47 ± 0.05, 10.88 ± 0.9, 9.68 ± 0.06, and 8.33 ± 0.01, respectively, by Folin-Ciocalteau method. The essential oil showed up to 90% zone inhibition against Fusarium moniliforme in inverted petri plate method. Using agar well diffusion method for evaluating antibacterial activity, the essential oil was found to be highly effective against Gram-positive bacteria.

Thymoquinone treatment against acetaminophen-induced hepatotoxicity in rats

AIM

In this study, we aimed to examine the efficacy of thymoquinone (TQ) treatment in acetaminophen-induced liver toxicity in rats.

METHODS

Forty Wistar Albino rats were used for the study (four groups, with 10 rats for each group). Animals in the control group were not given any medication. In the thymoquinone (TQ) group, animals were given three times 5 mg/kg oral thymoquinone for every six hours, which equals to a total dose of 15 mg/kg. In the acetaminophen (APAP) group, animals were given APAP at a single dose of 500 mg/kg orally. In the APAP + TQ group, animals were given 500 mg/kg APAP orally followed by three doses of TQ at a 15 mg/kg total dose in an 18-h time interval. All animals were sacrificed at the 24th hour. Alanine amino transferase (ALT), aspartat amino transferase (AST), superoxide dismutase (SOD), oxidized glutathione (GSSG), glutathione peroxides (GSH-Px), and malondialdehyde (MDA) activities were measured in rat blood. Histopathological examination was also performed.

RESULTS

Serum ALT, AST levels, GSSG, and SOD activity as well as the serum and tissue MDA levels were found to be higher in the APAP group than in the control group (p ≤ 0.001). Likewise, serum GSH-Px activity was found to be lower in the APAP group (p ≤ 0.001). In contrast, in the APAP + TQ group, serum ALT, AST levels, GSSG, SOD activity and the serum and tissue MDA levels were found to be lower compared to that of the APAP group. This difference was statistically significant (p ≤ 0.001). In the APAP + TQ group, the GSH-Px activity was found to be significantly higher compared to the APAP group (p < 0.05). In contrast to this finding, the GSH-Px activity in the APAP + TQ group was found to be lower than that of the control group (p ≤ 0.001). Histopathological analysis revealed significant liver necrosis and toxicity with a high dose of APAP where TQ treatment was related with significantly lower liver injury scores.

CONCLUSION

TQ treatment may have an important therapeuthic effect via the upregulation of antioxidant systems in the APAP-induced liver hepatotoxicity in rats.

Antioxidant effect of garlic (Allium sativum) and black seeds (Nigella sativa) in healthy postmenopausal women

Objectives:

The objective of this study is to investigate the antioxidant effects of garlic extract and crude black seeds’ consumption on blood oxidant/antioxidant levels in healthy postmenopausal women.

Methods:

In total, 30 healthy postmenopausal women (mean age = 50.31 ± 4.23 years) participated. They ingested two garlic soft gels per day (each is equivalent to 1000 mg of fresh garlic bulb) and crude black seed grounded to powder in a dose of 3 g/day for 8 weeks. Oxidant (malondialdehyde) activity in plasma and antioxidants superoxide dismutase and glutathione peroxidase activities in erythrocytes were studied.

Results:

Significant low levels of plasma malondialdehyde with increased erythrocyte glutathione peroxidase and superoxide dismutase activities.

Discussion:

Menopause is associated with an increase in oxidative stress and a decrease in some antioxidant parameters. Consumption of garlic extracts and crude black seeds may have a beneficial effect on improved balance between blood oxidants and antioxidants in healthy postmenopausal women.

Authentication of Nigella sativa seed oil in binary and ternary mixtures with corn oil and soybean oil using FTIR spectroscopy coupled with partial least square

Fourier transform infrared spectroscopy (FTIR) combined with multivariate calibration of partial least square (PLS) was developed and optimized for the analysis of Nigella seed oil (NSO) in binary and ternary mixtures with corn oil (CO) and soybean oil (SO). Based on PLS modeling performed, quantitative analysis of NSO in binary mixtures with CO carried out using the second derivative FTIR spectra at combined frequencies of 2977–3028, 1666–1739, and 740–1446 cm⁻¹ revealed the highest value of coefficient of determination (R², 0.9984) and the lowest value of root mean square error of calibration (RMSEC, 1.34% v/v). NSO in binary mixtures with SO is successfully determined at the combined frequencies of 2985–3024 and 752–1755 cm⁻¹ using the first derivative FTIR spectra with R² and RMSEC values of 0.9970 and 0.47% v/v, respectively. Meanwhile, the second derivative FTIR spectra at the combined frequencies of 2977–3028 cm⁻¹, 1666–1739 cm⁻¹, and 740–1446 cm⁻¹ were selected for quantitative analysis of NSO in ternary mixture with CO and SO with R² and RMSEC values of 0.9993 and 0.86% v/v, respectively. The results showed that FTIR spectrophotometry is an accurate technique for the quantitative analysis of NSO in binary and ternary mixtures with CO and SO.

Therapeutic potential of thymoquinone against anti-tuberculosis drugs induced liver damage

Hepatotoxicity is the most serious adverse effect related to tuberculosis treatment which interrupts the successful completion of tuberculosis treatment. The purpose of this study was to assess therapeutic effect of thymoquinone (TQ) against anti-tuberculosis drugs (ATD) induced liver damage. Rats were treated with ATD for 8 weeks (3 days/week) as given for the treatment of TB. This was followed by therapy of TQ for 8 weeks (3 days/week). Administration of combined ATD induced hepatotoxicity was evident from a significant elevation in the AST, ALT, ALP, bilirubin, albumin, cholesterol, urea, uric acid, creatinine, LPO and decreased activities of enzymes. These altered variables were significantly reversed toward control after treatment with TQ. Histological studies also supported biochemical findings. Results of this study strongly indicated protective effect of TQ and thus, can be expected as promising protective agent in maintenance of normal hepatic function during treatment with ATD.

Cardiovascular benefits of black cumin (Nigella sativa)

Black Cumin (Nigella sativa), which belongs to the botanical family of Ranunculaceae, commonly grows in Eastern Europe, the Middle East, and Western Asia. Its ripe fruit contains tiny black seeds, known as "Al-Habba Al-Sauda" and "Al-Habba Al-Barakah" in Arabic and black seed or black cumin in English. Seeds of Nigella sativa are frequently used in folk medicine in the Middle East and some Asian countries for the promotion of good health and the treatment of many ailments. However, data for the cardiovascular benefits of black cumin are not well-established. We reviewed the literature from 1960 to March 2012 by using the following key words: "Nigella sativa," "black seeds," and "thymoquinone." Herein, we discussed the most relevant articles to find out the role of Nigella sativa in the cardiovascular diseases spectrum especially when there is a paucity of information and need of further studies in human to establish the utility of Nigella sativa in cardiovascular system protection.