Dr. Weeks’ Comment: Spring is here and with the sun and warmth comes… blossoms and …… allergic challenges for people with asthma or hay fever. SOUL which features black cumin seed is delighting people almost as much as spring itself! Here is the science to review.
Pharmacological and toxicological properties of Nigella sativa.
Abstract
The seeds of Nigella sativa Linn. (Ranunculaceae), commonly known as black seed or black cumin, are used in folk (herbal) medicine all over the world for the treatment and prevention of a number of diseases and conditions that include asthma, diarrhoea and dyslipidaemia. This article reviews the main reports of the pharmacological and toxicological properties of N. sativa and its constituents. The seeds contain both fixed and essential oils, proteins, alkaloids and saponin. Much of the biological activity of the seeds has been shown to be due to thymoquinone, the major component of the essential oil, but which is also present in the fi ed oil. The pharmacological actions of the crude extracts of the seeds (and some of its active constituents, e.g. volatile oil and thymoquinone) that have been reported include protection against nephrotoxicity and hepatotoxicity induced by either disease or chemicals. The seeds/oil have antiinflammatory, analgesic, antipyretic, antimicrobial and antineoplastic activity. The oil decreases blood pressure and increases respiration. Treatment of rats with the seed extract for up to 12 weeks has been reported to induce changes in the haemogram that include an increase in both the packed cell volume (PCV) and haemoglobin (Hb), and a decrease in plasma concentrations of cholesterol, triglycerides and glucose. The seeds are characterized by a very low degree of toxicity. Two cases of contact dermatitis in two individuals have been reported following topical use. Administration of either the seed extract or its oil has been shown not to induce significant adverse effects on liver or kidney functions. It would appear that the beneficial effects of the use of the seeds and thymoquinone might be related to their cytoprotective and antioxidant actions, and to their effect on some mediators of inflammation.
Copyright 2003 John Wiley & Sons, Ltd.
Effect of dexamethasone and Nigella sativa on peripheral blood eosinophil count, IgG1 and IgG2a, cytokine profiles and lung inflammation in murine model of allergic asthma.
Abstract
It has been reported that Nigella sativa oil possesses anti-inflammatory and bronchodilator activities. Besides, non – toxic and wide margin of safety for therapeutic doses compared with Dexamethasone. This work aims to study the effect of Nigella sativa and Dexamethason on different immune and inflammatory parameters in a mouse model of allergic asthma. Mice sensitized intraperitoneally and challenged intratracheally with conalbumin were treated with Nigella sativa 24 hours after the first intratracheal challenge. Dexamethasone treated and naïve mice served as controls. The effect of Nigella sativa and Dexamethasone treatment on peripheral blood eosinophil count, IgG1 and IgG2a, cytokine profiles and lung inflammation were evaluated. Nigella sativa was significantly reduced peripheral blood eosinophil count, IgG1 and IgG2a levels, cytokine profiles and inflammatory cells in lung tissue. These effects were equivalent to the effects of Dexamethasone except unchanged IFN-y level. Nigella sativa exhibits anti-airway inflammation and immunoregulatory effect which may be useful for treatment of allergic asthma.
- PMID:
- 16734144
- [PubMed – indexed for MEDLINE]
Downregulation of leukotriene biosynthesis by thymoquinone attenuates airway inflammation in a mouse model of allergic asthma.
Abstract
Chronic airway inflammation is a key feature of bronchial asthma. Leukotrienes are potent inflammatory mediators that play a role in the pathophysiology of asthma, and their levels are elevated in the airways in response to allergen challenge. We examined the anti-inflammatory effect of thymoquinone (TQ), the active principle in the volatile oil of Nigella sativa seeds, on leukotriene (LT) biosynthesis in a mouse model of allergic asthma. Mice sensitized and challenged with ovalbumin (OVA) antigen had an increased amounts of leukotriene B4 and C4, Th2 cytokines, and eosinophils in bronchoalveolar lavage (BAL) fluid. In addition, there was also a marked increase in lung tissue eosinophilia and goblet cell numbers. Administration of TQ before OVA challenge inhibited 5-lipoxygenase, the main enzyme in leukotriene biosynthesis, expression by lung cells and significantly reduced the levels of LTB4 and LTC4. This was accompanied by a marked decrease in Th2 cytokines and BAL fluid and lung tissue eosinophilia, all of which are characteristics of airway inflammation. These results demonstrate the anti-inflammatory effect of TQ in experimental asthma.
Inhibition of 5-lipoxygenase and leukotriene C4 synthase in human blood cells by thymoquinone.
Abstract
Black cumin seed, Nigella sativa L., and its oils have traditionally been used for the treatment of asthma and other inflammatory diseases. Thymoquinone (TQ) has been proposed to be one of the major active components of the drug. Since leukotrienes (LTs) are important mediators in asthma and inflammatory processes, the effects of TQ on leukotriene formation were studied in human blood cells. TQ provoked a significant concentration-dependent inhibition of both LTC4 and LTB4 formation from endogenous substrate in human granulocyte suspensions with IC50 values of 1.8 and 2.3 microM, respectively, at 15 min. Major inhibitory effect was on the 5-lipoxygenase activity (IC50 3 microM) as evidenced by suppressed conversion of exogenous arachidonic acid into 5-hydroxy eicosatetraenoic acid (5HETE) in sonicated polymorphonuclear cell suspensions. In addition, TQ induced a significant inhibition of LTC4 synthase activity, with an IC50 of 10 microM, as judged by suppressed transformation of exogenous LTA4 into LTC4. In contrast, the drug was without any inhibitory effect on LTA4 hydrolase activity. When exogenous LTA4 was added to intact or sonicated platelet suspensions preincubated with TQ, a similar inhibition of LTC4 synthase activity was observed as in human granulocyte suspensions. The unselective protein kinase inhibitor, staurosporine failed to prevent inhibition of LTC4 synthase activity induced by TQ. The findings demonstrate that TQ potently inhibits the formation of leukotrienes in human blood cells. The inhibitory effect was dose- and time-dependent and was exerted on both 5-lipoxygenase and LTC4 synthase activity.
Effect of Nigella sativa (black seed) on subjective feeling in patients with allergic diseases.
Abstract
Nigella sativa (black seed) is an important medicinal herb. In many Arabian, Asian and African countries, black seed oil is used as a natural remedy for a wide range of diseases, including various allergies. The plant’s mechanism of action is still largely unknown. Due to the lack of study data on its efficacy in allergies, four studies on the clinical efficacy of Nigella sativa in allergic diseases are presented. In these studies, a total of 152 patients with allergic diseases (allergic rhinitis, bronchial asthma, atopic eczema) were treated with Nigella sativa oil, given in capsules at a dose of 40 to 80 mg/kg/day. The patients scored the subjective severity of target symptoms using a predefined scale. The following laboratory parameters were investigated: IgE, eosinophil count, endogenous cortisol in plasma and urine, ACTH, triglycerides, total cholesterol, LDL and HDL cholesterol and lymphocyte subpopulations. The score of subjective feeling decreased over the course of treatment with black seed oil in all four studies. A slight decrease in plasma triglycerides and a discrete increase in HDL cholesterol occurred while the lymphocyte subpopulations, endogenous cortisol levels and ACTH release remained unchanged. Black seed oil therefore proved to be an effective adjuvant for the treatment of allergic diseases.
Copyright 2003 John Wiley & Sons, Ltd.
Thymoquinone-induced relaxation of guinea-pig isolated trachea.
Abstract
The effect of thymoquinone (TQ), the main constituent of the volatile oil of black seed (Nigella sativa), on the guinea-pig isolated tracheal zig-zag preparation was investigated. TQ caused a concentration-dependent decrease in the tension of the tracheal smooth muscle precontracted by carbachol. The effects of TQ were significantly potentiated by pretreatment of the tracheal preparations with quinacrine, a phospholipase A2 inhibitor, nordihydroguiaretic acid, a lipoxygenase inhibitor and by pretreatment with methylene blue, an inhibitor of soluble guanylyl cyclase. On the other hand, the effects of TQ were not influenced by pretreatment of the tracheal preparations with indomethacin, a cyclooxygenase inhibitor, propranolol, a non-selective beta-adrenoceptor blocker or by the pretreatment with theophylline, an adenosine receptors antagonist TQ totally abolished the pressor effects of histamine and serotonin on the guinea-pig isolated tracheal and ileum smooth muscles. The results of the present study suggest that TQ induced relaxation of precontracted tracheal preparation is probably mediated, at least in part, by inhibition of lipoxygenase products of arachidonic acid metabolism and possibly by non-selective blocking of the histamine and serotonin receptors. This relaxant effect of TQ, further support the traditional use of black seeds either alone or in combination with honey to treat bronchial asthma.
- PMID:
- 12889525
- [PubMed – indexed for MEDLINE]
The possible prophylactic effect of Nigella sativa seed extract in asthmatic patients.
Erratum in
- Fundam Clin Pharmacol. 2008 Feb;22(1):105.
Abstract
In previous studies, the relaxant, anticholinergic (functional antagonism) antihistaminic, effects of Nigella sativa have been demonstrated on guinea-pig tracheal chains. In the present study, the prophylactic effect of boiled extract of N. sativa on asthmatic disease was examined. Twenty-nine asthmatic adults were randomly divided into control group (14 patients) and study group (15 patients), and they were studied for 3 months. In the study group 15 mL/kg of 0.1 g% boiled extract and in the control group a placebo solution was administrated daily throughout the study. Asthma symptom score, asthma severity, frequency of symptoms/week and wheezing were recorded in the beginning (first visit), 45 days after treatment (second visit), and at the end of the study (third visit). Pulmonary function tests (PFTs) were also measured, and the drug regimen of the patients was evaluated at three different visits. All asthma symptoms, frequency of asthma symptoms/week, chest wheezing, and PFT values in the study group significantly improved in the second and third visits compared with the first visit (P < 0.05 to P < 0.001). In addition, further improvement of chest wheezing and severity of disease on the third visit were observed compared with the second visit in this group (P < 0.05 for both cases). In the third visit all symptoms in the study group were significantly different from those of the control group (P < 0.01 to P < 0.001). However, in the control group, there were only small improvements in some parameters in just the second visit. The usage of inhaler and oral beta-agonists, oral corticosteroid, oral theophylline and even inhaler corticosteroid in the study group decreased at the end of the study while there were no obvious changes in usage of the drugs in control subjects. The results of phase I study generally suggest a prophylactic effect of N. sativa on asthma disease and warrant further research regarding this effect.
Bronchodilator, spasmolytic and calcium antagonist activities of Nigella sativa seeds (Kalonji): a traditional herbal product with multiple medicinal uses.
Abstract
OBJECTIVE:
The seeds of Nigella sativa locally known as “Kalonji” has been used in traditional medicine for the treatment of a variety of diseases including diarrhoea and asthma. The crude extract of N. sativa seeds (Ns.Cr) was studied in vitro for its possible spasmolytic and bronchodilator activities to rationalize the folkloric uses.
METHODS:
Isolated rabbit jejunum and guinea-pig tracheal preparations were set up in Tyrode’s and Kreb’s solutions respectively and aerated with 5% CO2 in oxygen. Isotonic and isometric responses were measured on Bioscience oscillograph and Grass polygraph respectively.
RESULTS:
The Ns.Cr caused a dose-dependent (0.1-3.0 mg/ml) relaxation of spontaneous contractions in rabbit jejunum. Ns.Cr also inhibited K(+)-induced contractions in a similar dose range, suggestive of calcium channel blockade (CCB). This effect was confirmed when pretreatment of the tissue with Ns.Cr, produced a dose-dependent shift in the Ca++ dose-response curves to the right similar to that of verapamil, a standard calcium channel blocker. In guinea-pig trachea, it caused relaxation of carbachol-, histamine- or K(+)-induced contractions indicating CCB. Activity-directed fractionation revealed that the CCB activity is concentrated in the petroleum ether fraction, which was found to be approximately 10 times more potent than the crude extract both in jejunum and tracheal preparations.
CONCLUSION:
These data indicate that the crude extract of Nigella sativa seeds exhibits spasmolytic and bronchodilator activities mediated possibly through calcium channel blockade and this activity is concentrated in the organic fraction. Its usefulness for diarrhoea and asthma in traditional medicine, appears thus to be based on a sound mechanistic background.