Investigating gender differences in Alzheimer's disease

Alzheimer's disease (AD) is an age-related neurodegenerative disorder that is characterized by neurocognitive dysfunction, deposition of amyloid-β (Aβ) plaques, and formation of hyperphosphorylated tau protein. Oxidative stress and neuroinflammation are the main pathological events in AD development. AD is a gender-dependent brain disorder that is predominant in females. Cessation of production of female hormones, such as 17β-estradiol (either due to menopausal or surgical menopause causes), exhibited pro-AD and neurotoxic activities that deteriorate cognitive functions and promote AD development. We investigated the key regulatory role of gender-dependent factors that control the process of AD neuropathogenesis, on the activities of Nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome, Nuclear factor erythroid 2-related factor 2 (Nrf2), and Apolipoprotein E (APOE). This review aimed to examine the impact of gender-based differences on incidence rates of AD dementia and to reveal the mechanisms regulating the gender differences in AD. In addition, we highlighted the anti-AD activities of sex hormones and the current application of hormonal replacement therapy and estrogen receptor beta-based therapeutic interventions. Furthermore, we presented the impact of gender differences on metabolism in the brain, insulin resistance, and astrocytic activity.