Teratogenic Potential of Thymoquinone [the main constituent of the Black Seed] in Rats

This study investigated embryotoxic and teratogenic effects of thymoquinone, the main constituent of the Black Seed [Nigella sativa]. All tests were done on rats. Pregnant rats were treated with various doses of thymoquinone [3.12, 6.25,12.5 and 25 mgkg, i.p.] from 7[th] to 16[th] day of gestation. Different doses of thymoquinone [TQ] did not induce any significant changes in fetal sex ratio, resorptions and litter size. Gross external malformations were not observed. Lower doses of TQ [3.12 and 6.25 mg/kg] significantly, retarded neonatal body weights. Higher doses [12.5 and 25 mg/kg] seemed to be safe, as they did not affect fetal growth. In conclusion, this study showed that low doses of TQ [3.125 and 6.25 mg/kg, i.p.] were f etotoxic in rats

Toxic potential of ethanolic extract of Acacia nilotica [Garad] in rats

The study aimed to investigate acute and sub-acute toxic potential of ethanolic extract of Acacia nilotica [Garad] in rats. LD50 of Garad was determined. Changes in behavioral response, induced by sub-acute treatments were recorded. Elevated urea, creatinine, ALT [GPT] and AST [GOT] in plasma were taken as evidence for impaired kidney and liver function. LD50 of Garad extract was found to be 215.36 mg/kg [124.84-317.47]. Regarding sub acute treatment, observations on seventh and fourteenth days showed slight to moderate sedation at various doses. On day 21 no behavioral changes were recorded. However, a treatment for three weeks induced significant elevation in urea and ALT [p<0.05]. It can be concluded that the ethanolic extract of Garad has got some toxicity when administered sub acutely and intraperitoneally in rats, particularly at high dose [60 mg/kg]

Potentiation of valproate-induced anticonvulsant response by nigella sativa seed constituents: the role of GABA receptors

This study investigated antiepileptic effects of the main constituents of Nigella sativa [NS] seed [i.e. aqueous extract [AE], fixed oil [FO], volatile oil [VO]] and the main components of its VO [i.e. thymoquinone, alpha-pinene and p-cymene] using pentylenetetrazole [PTZ] and maximal electroshock [MES]-induced convulsions. The potential of these constituents to induce minimal neurological deficit [MND] was also evaluated by using chimney test. Except for the FO, all of the NS seed constituents protected mice effectively against PTZ-induced convulsions. The activity of the VO in this model maybe attributed mainly to its content of thymoquinone and p-cymene and to a lesser extent, alpha-pinene. VO and its component p-cymene effectively suppressed convulsions induced by MES. The contents of p-cymene present in the effective dose of the VO maybe partially responsible for its anti-seizure effects. All of the NS seed constituents induced varying degrees of MND in the chimney test. MND induced by VO may pertain to its contents of thymoquinone [63%], p-cymene [23%] and alpha-pinene [<14%]. Protective indices of p-cymene and thymoquinone were closer to one, but only in PTZ model. Exploration on the role of receptors suggests that picrotoxin and bicuculline-sensitive GABA receptors, most probably GABAA receptors, mediate an increase in GABAergic response. In the part dealing with the interaction of valproate with thymoquinone, it can be mentioned that thymoquinone increased the potency of valproate in both PTZ and MES models