To improve the water solubility of thymoquinone (TQ), a major constituent of Nigella sativa seed oil, a TQ-loaded self-nanoemulsifying drug delivery system (SNEDDS) was prepared. The SNEDDS formulation was optimized using almond oil (AO) (Oil; X1), tween 80 (surfactant; X2) and polyethylene glycol 200 (PEG 200) (cosurfactant; X3) compounds as independent variables. The results showed that the globule size ranged from 65 to 320 nm. In addition, a strong agreement was reached between the system estimation and the experimental values of globule size. To evaluate the gastroprotective effect of optimized TQ-loaded SNEDDS against indomethacin (Indo.)-induced gastric ulcers in comparison with non-emulsified TQ, the ulcer index and histopathological changes were estimated. Optimized TQ-loaded SNEDDS showed improved gastroprotective activity against Indo.-induced ulcers relative to the non-emulsified TQ. In addition, the gastroprotective index was improved by 2-fold in TQ-loaded SNEDDS as compared to non-emulsified TQ. This is attributed to the strong antioxidant and the cytoprotective activities of the TQ. These results demonstrate enhancement of the efficacy of TQ through the optimized SNEDDS.
Optimization of Thymoquinone-Loaded Self-Nanoemulsion for Management of Indomethacin-Induced Ulcer