Comparative study of hypoglycaemic and antioxidant potential of methanolic seed extract and oil of Nigella sativa on alloxanized diabetic rabbits.

The present study was aimed to investigate the comparative antidiabetic potential of Nigella sativa seed extract and oil in an in vivo trial using rat animal model. The levels of antioxidants analysed in this study included catalase, vitamin C and bilirubin. NS methanolic extract and its oil were tested for their hypoglycemic effect against alloxanized diabetic rabbits (120mg/kg). The crude methanolic extract and the oil (2.5ml/kg/day) were given orally for 24 days that resulted in a significant reduction in glycaemia, particularly during the first 12 days of treatment (reductions of 58.09% and 73.27%, respectively), whereas the oil treated group normalised the levels of catalase (-69.23%), vitamin C (27.30%) and bilirubin (-51.48%) and the extract treated group normalised the levels of catalase (-65.38), vitamin C (24.15%) and bilirubin (-26.19%) at the end of the trial. The results have shown that the seed oil more significantly normalized the levels of serum catalase, serum ascorbic acid and total serum bilirubin as compared to the methanolic extract of Nigella sativa, so Nigella sativa seed oil (NSO) may be used as part of antidiabetic remedies against diabetes and utilized as a nutraceutical.

Comparative hepatoprotective effect of Nigella sativa pre- and post-treatment to rabbits.

Synthetic drugs are associated with adverse side-effects and rapid increase in resistance to most of them inspires to evaluate plants for their therapeutic values. We have been aimed to suggest the medicinal use of Nigella sativa seed aqueous extract to minimize the severity of liver damage via its antioxidant properties and its role in maintenance of cell ion-homeostasis. Annoyances in serum levels of some antioxidants and trace metals in human hepatitis C infected patients were compared with that from acetaminophen-induced hepatotoxic rabbits. Serum analysis of human patients and that of hepatotoxic rabbits have exhibited the same trend of incidence of liver marker enzymes, antioxidant levels, and trace metal concentrations, except for the serum levels of cobalt. Significance of pre-/ or post-treatment of Nigella sativa to acetaminophen induced-hepatotoxic rabbit has also evaluated. NS post-treatment to rabbits has been found effective in normalizing the levels (P<0.001) of serum liver markers; especially the ALP levels, and the antioxidants; with significant effect on the serum catalase levels. However, NS pre-treatment has shown its role (P<0.001) in maintaining the serum nickel and cobalt concentrations. Therefore, we suggest the use of Nigella sativa seeds as pre-/ or post-treatment therapy, and also as supplement to the normal medications of liver infection to normalize the status of cell antioxidants and trace metal concentrations.

Potential of Nigella sativa seed aqueous extract in ameliorating quinine-induced thrombocytopenia in rats.

Dengue infection is rapidly spreading in most of the countries of south Asia. It is of utmost importance to explore the plants with "anti-thrombocytopenic activity" the dreadful response of dengue fever. The present study was conducted to investigate the potential of aqueous extract of Nigella sativa (black cumin) seeds in alleviating the severity of dengue disease by raising the platelet count (PLT). Serum samples of thirty patients with dengue hemorrhagic fever (DHF) were analysed for different biochemical parameters. When compared with control groups, the patients were found with very low PLT count (7.62 fold), reduced antioxidant levels; catalase (1.4 fold), ascorbic acid (1.1 fold), bilirubin (1.06 fold), and severe deficiency of micronutrient concentrations; cobalt (2.27 fold), iron (2.35 fold) and nickel (71.46 fold). Similar parameters were studied in albino rats to observe the changes in serum levels of biochemical markers, after administration of single dose of choloroquine phosphate (IM, 1.5 mL saline). The drug successfully induced thrombocytopenia along with significant decrease in levels of antioxidants and trace metals. Administration of N. sativa aqueous seed extract (15.25 mg/kg/bw) for 12 days resulted in an increase in PLT count (1.59 fold) as compared to control group. N. sativa post-treatment was found effective in elevating the serum levels of catalase, ascorbic acid, and bilirubin (1.06, 1.58 and 0.4 folds respectively). However, the N. sativa pre-treatment was useful in increasing the levels of micronutrients; iron, nickel and cobalt when compared to quinine-induced group. From the above findings it was suggested that N. sativa seed aqueous extract supplementation would be a promising solution for declined PLT count and associated consequences.