Background: Aluminum (AL) is toxic to the central nervous system, and Nigella Sativa (NS) reduces lipid peroxidation by its antioxidant activity.
Objective: This study was carried out to investigate the histological changes in the cerebellar cortex of rats after AL treatment and to detect any possible protective role of NS when given concomitantly with AL.
Materials and methods: This study was carried out on 25 adult male albino rats, each one weighing 100 g. They were divided into five groups: Control group (5 rats) received no treatment, Group I (NS treated group) (5 rats) received nigella sativa oil only at a dose level of 1ml/kg orally for 1.5 month. Group II (AL-treated group) (5 rats) received aluminum chloride daily in a dose of 320 mg/kg/L added to the drinking water for 1.5 month. Group III (AL + NS) (5 rats) received NS with AL for 1.5 month in the same dose of AL and NS of the two previous groups. Group IV (withdrawal) (5 rats) received AL only without NS in the same previous dose of AL for 1.5 month and then animals left without treatment for another 1.5 month . The animals of each group were randomly divided into two subgroups; the first was processed for light and the second for transmission electron microscopic study. The sections of the cerebellar cortex for light microscopic study were stained with Hematoxylin and Eosin and Toluidine blue (semithin sections). Morphometric and statistical analysis were conducted.
Results: The NS treated group showed non-significant changes compared to control. After AL administration, the cerebellum exhibited degenerative changes in Purkinje cells and in granular layer as well as significant reduction in the number of Purkinje cells and prominent perineuronal spaces in the molecular layer around basket and stellate cells and in the Purkinje cell layer. Ultrastructurally, some of the few encountered Purkinje cells showed swollen mitochondria with ruptured membranes and cristae. Granule cells were rich in mitochondria which were variable in size and shap in addition to presence of irregular areas of degeneration. Concomitant administration of NS with AL displayed an observable protection against these changes. Withdrawal group showed degenerative changes and a significant difference compared to NS + AL group.
Conclusion: NS may have a protective role against AL-induced cerebellar toxicity in humans.