ovalbumin and thymoquinone

Many investigations have demonstrated the prophylactic effect of Nigella sativa on asthma disease. One of its active constituents is α-hederin. In the present study, the preventive effect of two different concentrations of α-hederin on tracheal responsiveness and lung inflammation in ovalbumin-sensitized guinea pigs was examined. Forty male adult Dunkin-Hartley guinea pigs were randomly divided into the control (C), sensitized (S) and sensitized pretreated groups with thymoquinone (3 mg/kg i.p., S + TQ), low-dose α-hederin (0.3 mg/kg i.p., S + LAH) and high-dose α-hederin (3 mg/kg i.p., S + HAH). The responsiveness of tracheal smooth muscle (TR) to methacholine, histamine and ovalbumin was assessed. Moreover, total and differential white blood cell counts in lung lavage fluid were examined. Compared with the S group, the mean EC50 value in the S + LAH group increased significantly (p < 0.05). The mean EC50 value of histamine contraction in the S + LAH and S + HAH groups was significantly higher than in the S group (p < 0.05). In all pretreated groups, the TR to ovalbumin decreased in comparison to the S group (p < 0.001). Both the S + HAH and S + LAH groups showed significantly decreased TR compared to the S + TQ group (p < 0.01-p < 0.01). Total WBC and eosinophil counts in all pretreated groups decreased significantly in comparison with the S group (0.001-0.01). There was a significant increase in neutrophil, lymphocyte and monocyte counts in the pretreated groups compared to the S group (p < 0.001-p < 0.05). The basophil count in the S + TQ and S + HAH groups was significantly lower than in the S group (p < 0.01-p < 0.05). This study suggested that α-hederin has anti-inflammatory and bronchodilatory effects like thymoquinone.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoquinones; Bronchodilator Agents; Guinea Pigs; Histamine; Male; Methacholine Chloride; Nigella sativa; Oleanolic Acid; Ovalbumin; Plants, Medicinal; Pneumonia; Saponins; Trachea

In the present study, the preventive effect of two different concentrations of α-hederin, the active constituent of Nigella sativa, on lung inflammation and blood cytokines in ovalbumin sensitized guinea pigs was examined. Forty eight male adult guinea pigs were divided into control (C), sensitized (S) and sensitized pretreated groups; with thymoquinone (S+TQ), low dose (S+LAH) and high dose of α-hederin (S+HAH) and inhaled fluticasone propionate (S+FP). The lung histopathology and blood levels of IL-4, IFN-γ and IL-17 were assessed. Compared to sensitized animals, all pathological changes improved significantly in pretreated groups (p < 0.001 to p < 0.05). These improvements in α-hederin pretreated groups were similar to S+TQ and S+FP groups except cellular infiltration in S+LAH and S+HAH groups which was lower than S+TQ group (p < 0.05). The blood IL-4 and IL-17 levels in S+HAH groups showed a significant decrease compared to S group (p < 0.05) which were similar to S+TQ and S+FP groups. The level of IFN-γ in S+LAH and S+HAH groups increased significantly compared to S group (p < 0.05) which was higher than S+FP group (p < 0.05). Blood IL-4 in S+HAH group was significantly lower than S+LAH group (p < 0.05). In conclusion, α-hederin could attenuate the lung inflammation and improve the changes of cytokines like thymoquinone and fluticasone in used dosages.

Topics: Animals; Benzoquinones; Cytokines; Drugs, Chinese Herbal; Fluticasone; Guinea Pigs; Interleukin-17; Interleukin-4; Lung; Male; Nigella sativa; Oleanolic Acid; Ovalbumin; Plant Extracts; Pneumonia; Saponins

The incidence of food hypersensitivity and food allergies is on the rise and new treatment approaches are needed. We investigated whether N. sativa, one of its components, thymoquinone, or synthetic opioid receptor (OR)-agonists can alleviate food allergy. Hence, ovalbumin (OVA)-sensitized BALB/c-mice were pre-treated either with a hexanic N. sativa seed extract, thymoquinone, kappa-(U50'4889) or mu-OR-agonists (DAMGO) and subsequently challenged intra-gastrically with OVA. All 4 treatments significantly decreased clinical scores of OVA-induced diarrhea. N. sativa seed extract, thymoquinone, and U50'488 also decreased intestinal mast cell numbers and plasma mouse mast cell protease-1 (MMCP-1). DAMGO, in contrast, had no effect on mast cell parameters but decreased IFNγ, IL-4, IL-5, and IL-10 concentration after ex vivo re-stimulation of mesenteric lymphocytes. The effects on allergy symptoms were reversible by OR-antagonist pre-treatment, whereas most of the effects on immunological parameter were not. We demonstrate that N. sativa seed extract significantly improves symptoms and immune parameters in murine OVA-induced allergic diarrhea; this effect is at least partially mediated by thymoquinone. ORs may also be involved and could be a new target for intestinal allergy symptom alleviation. N. sativa seed extract seems to be a promising candidate for nutritional interventions in humans with food allergy.

Topics: Animals; Benzoquinones; Biomarkers; Chymases; Diarrhea; Food Hypersensitivity; Ligands; Male; Mice; Mice, Inbred BALB C; Nigella sativa; Ovalbumin; Phytotherapy; Plant Extracts; Receptors, Opioid; Receptors, Opioid, kappa; Receptors, Opioid, mu; Seeds

Thymoquinone (TQ) is an active and potent compound in the oil of Nigella sativa, which has anti-inflammatory properties. The aim of this study was to evaluate the effects of TQ on ovalbumin (OVA)-induced allergic conjunctivitis (AC) in Balb/c.. The mice were divided into seven experimental groups; PBS Con, OVA Con, Conj, 0.05%TQ, 0.1%TQ, 0.5%TQ and Dex group. The mice were immunized and exposed to OVA, and eyes were treated with TQ and dexamethasone. Ocular symptoms were observed after last exposure to OVA. Eosinophils count in blood and Ophthalmic lavage fluid (OLF), recruitment of inflammatory cells in conjunctiva, serum IgE and OVA-specific IgE were evaluated by Giemsa and HE staining, and Enzyme-Linked Immunosorbent Assay (ELISA) respectively. High Performance Liquid Chromatography (HPLC) was used to determine the histamine level in OLF. The mRNA expression and protein level of cytokines were examined by real time RT-PCR and ELISA respectively.. Ocular symptoms of AC and other characteristics of allergic inflammation including IgE and OVA-specific immunoglobulin E (IgE) level, recruitment of eosinophils, histamine level, mRNA expressions and protein level of cytokines were remarkably increased in OVA-exposed mice compared with the control groups. Administration of TQ suppressed the ocular symptoms, inflammatory cell infiltration in conjunctiva, blood and OLF, increased level of serum IgE and OVA-specific IgE, and OLF histamine level in OVA-exposed mice. Furthermore, TQ abrogated the mRNA expression and serum level of interleukin including 1L-4, IL-5, IL-13 and transforming growth factor beta (TGF-β) in mice immunized and exposed to OVA.. Administration of TQ significantly reduced the ocular symptoms in AC by attenuating the recruitment of eosinophils, level of IgE, histamine and cytokines. Our findings suggest that TQ might be a useful intimation for the treatment and future research for AC.

Topics: Animals; Benzoquinones; Chromatography, High Pressure Liquid; Conjunctivitis, Allergic; Cytokines; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Eosinophils; Histamine; Immunoglobulin E; Leukocyte Count; Mice; Mice, Inbred BALB C; Ovalbumin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

In previous studies, the relaxant, anticholinergic (functional antagonism) and antihistaminic, effects of Nigella sativa have been demonstrated on guinea pig tracheal chains. In the present study, the prophylactic effect of thymoquinone (one of the constituents of Nigella sativa) on tracheal responsiveness and white blood cell (WBC) count in lung lavage of sensitized guinea pigs was examined. Four groups of sensitized guinea pigs to ovalbumin (OA) were given drinking water alone (group S), drinking water containing low or high concentrations of thymoquinone (S + LTQ and S + HTQ groups) or inhaled fluticasone propionate (FP 250 microg) twice a day (positive control group) (n = 7, for all groups). Tracheal responses of control and four groups of sensitized animals to methacholine at an effective concentration causing 50 % of maximum response (EC(50) M) were measured. Tracheal responses to 0.1 % OA, relative to contraction induced by 10 microM methacholine were also examined. Total WBC and its differential count in lung lavage were also measured. The tracheal responsiveness to methacholine, OA and WBC of S guinea pigs was significantly higher than those of controls (p < 0.001 for all cases). Tracheal responsiveness in S + LTQ, S + HTQ, and FP groups to both methacholine (p < 0.05 to p < 0.001) and OA (p < 0.001 for all cases) was significantly decreased compared to that of the S group. Total WBC was also decreased in all experimental groups compared to that of the S group (p < 0.001 for all groups). There was an increase in eosinophils and a decrease in neutrophils, lymphocytes and monocytes in the S animals compared to the controls (p < 0.001 for all cases). Treatment with both concentrations of thymoquinone and FP variably improved differential WBC count changes compared to the S animals (nonsignificant to p < 0.001). The improvement in tracheal responsiveness, total WBC, eosinophils and lymphocytes changes in the S animals treated with both concentrations of TQ were significantly greater than those of FP (p < 0.05 to p < 0.001). These results showed a preventive effect of thymoquinone, one constituent of N. sativa, on tracheal responsiveness and inflammatory cells of lung lavage of sensitized guinea pigs which was comparable or even greater than that of the inhaled steroid.

Topics: Androstadienes; Animals; Anti-Inflammatory Agents; Benzoquinones; Bronchial Hyperreactivity; Bronchoalveolar Lavage; Bronchoconstrictor Agents; Female; Fluticasone; Guinea Pigs; Leukocyte Count; Leukocytes; Lung; Lymphocytes; Male; Methacholine Chloride; Nigella sativa; Ovalbumin; Phytotherapy; Plant Extracts; Trachea

Thymoquinone (TQ), the main active constituent of the volatile oil extracted from Nigella sativa's seeds, has been reported to have an anti-inflammatory and immune stimulatory effect on bronchial asthma and inflammation. However, little is known about the factors and mechanisms underlying these effects. In the present study, we examined the effect of TQ on airway inflammation in a mouse model of allergic asthma. Intraperitoneal injection of TQ before airway challenge of ovalbumin (OVA)-sensitized mice resulted in a marked decrease in lung eosinophilia and the elevated Th2 cytokines observed after airway challenge with OVA antigen; both in vivo, in the bronchoalveolar lavage (BAL) fluid and in vitro, following stimulation of lung cells with OVA. TQ also decreased the elevated serum levels of OVA-specific IgE and IgG1. Histological examination of lung tissue demonstrated that TQ significantly inhibited allergen-induced lung eosinophilic inflammation and mucus-producing goblet cells. While TQ showed a significant effect in inhibiting IL-4, IL-5 and IL-13 and some effect in inducing IFN-gamma production in the BAL fluid, it did show a slight effect on in vitro production of IL-4 by cultured lung cells stimulated with OVA antigen. These data suggest that TQ attenuates allergic airway inflammation by inhibiting Th2 cytokines and eosinophil infiltration into the airways; thus demonstrating its potential anti-inflammatory role during the allergic response in the lung.

Topics: Allergens; Animals; Anti-Inflammatory Agents; Benzoquinones; Bronchoalveolar Lavage Fluid; Cytokines; Disease Models, Animal; Female; Goblet Cells; Immunoglobulin E; Immunoglobulin G; Leukocyte Count; Lung; Male; Mice; Mice, Inbred BALB C; Ovalbumin; Pneumonia; Respiratory Hypersensitivity; Th2 Cells

Prostaglandins (PGs) are potent proinflammatory mediators generated through arachidonic acid metabolism by cyclooxygenase-1 and -2 (COX-1 and COX-2) in response to different stimuli and play an important role in modulating the inflammatory responses in a number of conditions, including allergic airway inflammation. Thymoquinone (TQ) is the main active constituent of the volatile oil extract of Nigella sativa seeds and has been reported to have anti-inflammatory properties. We examined the effect of TQ on the in vivo production of PGs and lung inflammation in a mouse model of allergic airway inflammation. Mice sensitized and challenged through the airways with ovalbumin (OVA) exhibited a significant increase in PGD2 and PGE2 production in the airways. The inflammatory response was characterized by an increase in the inflammatory cell numbers and Th2 cytokine levels in the bronchoalveolar lavage (BAL) fluid, lung airway eosinophilia and goblet cell hyperplasia, as well as the induction of COX-2 protein expression in the lung. Intraperitoneal injection of TQ for 5 days before the first OVA challenge attenuated airway inflammation as demonstrated by the significant decrease in Th2 cytokines, lung eosinophilia, and goblet cell hyperplasia. This attenuation of airway inflammation was concomitant to the inhibition of COX-2 protein expression and PGD2 production. However, TQ had a slight inhibitory effect on COX-1 expression and PGE2 production. These findings suggest that TQ has an anti-inflammatory effect during the allergic response in the lung through the inhibition of PGD2 synthesis and Th2-driven immune response.

Topics: Allergens; Animals; Anti-Inflammatory Agents; Benzoquinones; Bronchial Hyperreactivity; Cyclooxygenase 1; Cyclooxygenase 2; Cytokines; Dinoprostone; Disease Models, Animal; Female; Gene Expression Regulation; Male; Mice; Mice, Inbred BALB C; Ovalbumin; Prostaglandin D2; Th2 Cells