Effect of Nano-curcumin versus Black Seed Oil on Renal Cortical Changes Induced by Aspartame in Adult Male Albino Rat. Histological and Immunohistochemical Study

Introduction: Aspartame (ASP) is a widely used an artificial sweetener. However, it is considered a risky compound causing many health problems on prolonged use. Curcumin and black seed oil (BSO) are two of the most important natural antioxidants used in alternative medicine. Recently, curcumin nano-formulations showed better bioavailability and solubility, hence delivering more therapeutic concentrations of curcumin, enhancing its efficacy.
Aim of the work: This study was carried out to investigate the effect of nano-curcumin versus BSO on aspartame-induced cortical histological changes in adult male albino rat.
Materials and methods: Forty-five rats were divided into 4 groups; 1 control and 3 experimental groups; Aspartame group: received aspartame orally (200 mg/ kg/day) for 6 weeks, nano-curcumin and BSO groups: received aspartame as the previous group concomitantly with nano-curcumin (200 mg/kg/day) and BSO (0.2 ml/kg/day) respectively orally for 6 weeks. Serum levels of urea and creatinine (Cr) and renal tissue level of superoxide dismutase (SOD) were measured. Renal sections were stained with H&E, Periodic Acid Schiff's Reaction (PAS) and immunohistochemical stains for Caspase-3, Cox-2 and Ki67. Additionally, morphometric measurements and statistical analysis were done.
Results: The aspartame group showed obvious histological degenerative changes in renal corpuscles and tubules with a significant decrease in the glomerular area, mean area% of PAS and mean number of Ki-67 immuno-positive cells with significant increase in the area% of COX-2 and caspase-3 immunoreaction. Whereas, nano-curcumin and BSO groups showed apparently normal structure of the renal cortex and amelioration of the biochemical and morphometric parameters detected in the aspartame group.
Conclusion: Both nano-curcumin and BSO proved a protective effect on the renal cortex against the adverse changes caused by aspartame and their efficiency was nearly similar. These findings can be considered clinically after extra human-based studies to define the suitable patient and to adjust the required dose.