The Blood Level of Leptin in Alzheimer’s Patients and Healthy Individuals

Document Type : Original Articles


1 Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan

2 Zanjan University of Medical Sciences


Background: Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by accumulation of extracellular amyloid-β plaques and intracellular neurofibrillary tangles tau protein. Obesity significantly increases the risk of developing AD. Leptin is a peptide hormone secreted by adipocytes. In the present study the serum levels of leptin in AD was evaluated. Material and method: This study was performed on 12 Alzheimer patients referred to Zanjan Vali-e-Asr Hospital, and 12 healthy individuals. Serum levels of leptin were measured by ELISA method. Results: Our results show that the level of leptin was significantly different in AD patients and control group. Considering the relationship between leptin levels and the age, oldest the patients, the lowest the levels of leptin hormone, in both male and female. Also, the severity of disease was related to the level of leptin hormone.  Conclusion: There presumably could be a cause and effect relationship between AD progress and reduction in the serum level of leptin. It may also point to the potential usage of measuring the leptin concentration in finding a biomarker for the disease.


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