Development and characterization of new indomethacin self-nanoemulsifying formulations

In the present work a new indomethacin [IND] self-nanoemulsifying drug delivery formulation [SNEDDF] have been prepared to enhance its dissolution which in turn could provide a better chance for IND oral absorption. IND SNEDDF have been prepared using different concentrations of castor oil as a solvent for IND, Cremophor RH 40 [Cr-40] as surfactant and Capmul MCM-C8 [Ca-8] as co-surfactant. Droplets size and turbidity of IND SNEDDFs were measured. Dissolution profile of IND SNEDDFs filled in gelatin capsules was determined by using USP apparatus 2. Ternary phase diagram was constructed to identify the self-nanoemulsifying region after evaluation of IND SNEDDFs by the visual observation. The IND SNEDDFs were thermally characterized using differential scanning calorimetry [DSC] to ensure the compatibility among its ingredients. The present study revealed that the SNEDDFs increased IND dissolution rate and has the potential to enhance its bioavailability without interaction or incompatibility between the ingredients

L-arginine augments the antioxidant effect of garlic against acetic acid induced ulcerative colitis in rats

Garlic contains many sulfhydryl compounds that act as antioxidants. However, the role of nitric oxide [NO] in inflammation is controversial. The aim of the present study is to investigate the possible protective effect of garlic against acetic acid-induced ulcerative colitis in rats, as well as the probable modulatory effect of L-arginine [NO precursor] on garlic activity. Intra-rectal inoculation of rats with 4% acetic acid for 3 consecutive days caused a significant increase in the colon weight and marked decrease in the colon length. In addition, acetic acid induced a significant increase in serum levels of nitrate as well as colonic tissue content of malondialdehyde [MDA]. Moreover, colonic tissue contents of glutathione [GSH], superoxide dismutase [SOD] and catalase [CAT] were markedly reduced. On the other hand, pre-treatment of rats with garlic [0.25g/kgbwt, orally] for 4 consecutive weeks and 3days during induction of colitis significantly reduced the increase in the colon weight induced by acetic acid and ameliorated alterations in oxidant and antioxidant parameters. Interestingly, oral co-administration of garlic [0.25g/kgbwt] and L-arginine [625mg/kgbwt] for the same period of garlic administration mitigated the changes in both colon weight and length induced by acetic acid and increased garlic effect on colon tissue contents of MDA and GSH. In conclusion, L-arginine can augment the protective effect of garlic against ulcerative colitis; an effect that might be mainly attributed to its NO donating property resulting in enhancement of garlic antioxidant effect. Further studies will be needed to determine which one of the active ingredients of garlic has the main antioxidant effect to be used with L-arginine