new insights into the effect of diabetes and obesity in alzheimer’s disease

abstract alzheimer’s disease (ad) is the most common cause of dementia in elderly people. the prevalence of alzheimer diseases is increasing in the world due to population aging. metabolic disease such as diabetes and obesity play important role in alzheimer disease. hyperglycemia can play important role in brain damage. it causes cognitive impairments, functional and structural alterations in the brain. since insulin has neuro protective effect in vivo, impaired insulin action in brain may affect neurodegenerative diseases. obesity correlated increased free fatty acid can lead to alzheimer disease. free fatty acids agitate the synthesis of amyloid and tau filaments in vitro. in this paper, alzheimer disease and its mechanism are discussed in section 1. in section 2, diabetes and alzheimer, brain insulin signaling pathway in ad are explained. obesity and oxidative stress in ad are discussed in section 3, 4.