Increased plasma levels of BDNF and inflammatory markers in Alzheimer's disease.

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Neurotrophic factors and inflammatory markers may play considerable roles in AD. In this study we measured, through Enzyme-Linked Immunosorbent Assay, the plasma levels of brain derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF) and neuronal growth factor (NGF), as well as tumor necrosis factor-alpha soluble receptors, sTNFR1 and sTNFR2, and soluble intercellular adhesion molecule 1 (sICAM-1), in 50 AD patients, 37 patients with mild cognitive impairment (MCI) and 56 healthy elderly controls.