Therapeutic Effects of Thymoquinone on Alzheimer's Disease through Modulating Amyloid-beta Neurotoxicity and Neuro-inflammatory Cytokine Levels

Abstract

Alzheimer's disease (AD) is a neurodegenerative disease that involves several impaired neuronal pathways. Modulating the amyloid-beta (β-amyloid) system is being tested to treat AD. Amyloid-beta neurotoxicity is associated with neuroinflammation and plaque formation, further progressing to AD. Protecting neurons from β-amyloid neurotoxicity could be an efficient strategy for the treatment of AD. Thymoquinone (TQ) is an active ingredient in Nigella sativa (NS) and has shown effective therapeutic properties in AD models. TQ was able to attenuate the behavioral dysfunctions in AD models. Moreover, TQ could attenuate the neuroinflammation properties in animals with AD. In addition, studies have shown that TQ could modulate β -amyloid neurotoxicity, an effect associated with improved AD behavioral symptoms. In this review, we highlighted the therapeutic effects of TQ on the progression of AD through modulating β-amyloid neurotoxicity and neuro-inflammatory cytokine levels. Other phenolic compounds also present in NS improved behavioral and neuronal impairments in AD models, supporting TQ's anti-Alzhiemer's efficacy.

Keywords: Alzheimer’s disease; Nigella sativa; acetylcholinesterase; amyloid-beta neurotoxicity; glutamate; neuroinflammation; thymoquinone therapy.