Evaluation of the effect of sleep disturbance on the immunohistochemical expression of beta Amyloid precursor protein in cerebral and cerebellar cortices of adult mice

Abstract

The circadian timing system , provides organization for most neurobehavioral, physiological, and biochemical variables, including the sleep-wake cycle .Circadian rhythm changes are associated with sleep disturbances during the day, neurodegenerative diseases is associated with sleep disturbance either as a causative factor or as a result, characterized by  protein folding and aggregation with  synaptic dysfunction and neuronal loss. Amyloid precursor protein has been linked to neurodegenerative disease as  it impair synapses, leading to memory loss and, dementia. This study aim to evaluate the effect of different types of sleep disturbance by light stimulation (sleep reduction, and sleep interruption) on the histological features and immunohistochemical expression of beta Amyloid precursor protein (ß APP) in cerebral and cerebellar cortices in adult male mice. Results showed marked histological changes in cerebral and cerebellar cortical cellular layers, Purkinji cells loss in cerebellar cortex, nuclear apoptotic changes, vascular changes and hemorrhage were more marked in sleep reduction group. Immunohistochemical study of ß APP showed significant increase in its expression in sleep reduction group compared to control and sleep interruption groups at P≤0.05. These changes emphasize on the importance of sleep in maintaining neural tissue integrity and homeostasis, as its concerned with clearance of neurotoxins.