Cytosolic Prostaglandin E Synthase: Expression Patterns in Control and Alzheimer's Disease Brains

Anti-inflammatory drugs reduce the risk of Alzheimer's disease but fail to slow its progression. Studying the expression of prostaglandin E-2 synthases downstream of cyclooxygenase-2 is important. Here, the expression patterns of cytosolic prostaglandin E-2 synthases, an immediate prostaglandin E-2 source was investigated. Sections taken from the middle frontal gyrus of brains of 10 patients with Alzheimer's and 5 age-matched controls were examined by immunostaining for the presence of the synthases. Immunofluorescence analysis of control brains showed that cytosolic prostaglandin E-2 synthases co-localize with microglia, neurone, and endothelium markers, but not with astrocytes or smooth muscle cells. Immunohistochemical staining for the synthases was positive in the pyramidal neurons of controls but barely detectable in the brain of Alzheimer's patients. These findings revealed that cytosolic prostaglandin E-2 synthases is found in microglia, neurons, and endothelium of control human middle frontal gyrus and that its levels decrease in pyramidal cells of Alzheimer's disease brains.