Possible therapeutic role of Grape (Vitis vinifera) Leaves Polyphenolic Extract in the regression of Aluminium-induced Alzheimer s disease in rats

Alzheimer’s disease (AD) is a multifactorial neurodegenerative disease. The main histological hallmark of AD-induced brain is neurotoxic amyloid-β (Aβ) plaques, accompanied with oxidative stress and disorders in lipid metabolism. This study demonstrated the therapeutic effect of Vitis vinifera (grape) Leaves Polyphenolic (VLP) extract on aluminium chloride (AlCl_3)-induced AD in aged male rats. AD- rats showed significant increase in oxidative stress biomarkers (malondialdehyde (MDA), nitric oxide (NO) and protein carbonyls (PC)), amyloid β (Aβ) and lipid profile markers, as well as, sphingomyelins (SM) and phosphatidylcholine (P.Ch.) were elevated. Additionally, brain total protein (TP) content showed significant reduction. The biochemical findings were supported with the histological investigation of brain tissues of AD-rats which demonstrated neurodegeneration in brain cells and amyloid plaques formation. While, treatment with VLP extract has effective role in brain tissue architecture restoration as well as modulating the aforementioned parameters. This work demonstrated that VLP extract has antioxidative, antihypercholesterolemic and antiamyloidogenic activities against AlCl3-induced oxidative stress and dementia in rats, indicating the therapeutic potential of polyphenols in regression of AD.