Diabetes is associated with an increase in the production of free radicals, reduction of tetrahydrobiopterin (BH4, THB) levels and reduced bioavailability of nitric oxide (NO) in the vascular walls. In this contribution, we probed the effective role of curcumin nanoparticles (CUR-NPs) that prepared via solvent evaporation nanoprecipitation technique as potential system to attenuate endothelial dysfunction. In this technique, Tween 60 (polysorbate) was used as stabilizing agent for the prepared CUR-NPs and protect such nanoparticles from further agglomeration. BH4 levels and other parameters were estimated in diabetic rats. To this end, we dedicated 48 male albino rats, categorized into six groups; control (healthy rats), diabetic rats, along with four treated groups via oral administration of 0.2 mL/kg body weight/day of solutions of Tween 60 (60 mg/mL), free CUR (60 mg/mL), CUR-NPs1 (30 mg/mL), and CUR-NPs2 (60 mg/mL) for 30 days. Results showed that the mean level of malondialdehyde (MDA) has been significantly increased in diabetic group associated with a reduction of total antioxidant capacity, NO, and BH4 compared to control. These parameters were restored by the delivery of CUR-NPs - both doses in rats, compared with the two control groups that treated with Tween 60 and free CUR.

Inflammation and pain triggers several pathological illnesses. Synthetic drugs used for the controlling of inflammatory conditions convey significant toxic effects. Global scientific community continually attempt to improve effective, economic and harmless naturally derived remedies against inflammation and pain. The present study aimed to quantify the phytochemical constituents of the freshly cultivated Spirulina and targeted to examining the anti-inflammatory and analgesic activity of Spirulina extract (SE) derived from Arthrospira platensis. The anti-inflammatory effect of SE was evaluated in animal models including carrageenan-induced rat hind paw oedema, and cotton pellet-induced granuloma formation. Analgesic effects of SE were evaluated by acetic acid induced writhing response and hot plate test. Phytochemical quantification guided to identify seven carbohydrates, thirteen amino acids, eleven fatty acids and polyphenolic compounds respectively. The results indicated that SE significantly attenuated carrageenan-induced hind paw oedema, and cotton pellet-induced granuloma. Preliminary molecular mechanistic studies established that SE decreased the productions of TNF-α, IL-1β, IL-6, PGE2 and NO, and suppressed the activities of COX-2 and iNOS. These results provide a strong scientific foundation for the anti-inflammatory and analgesic activities of SE against different studies in animal models.