Increased brain synthesis of prostaglandin E2 and F2-isoprostane in human and experimental transmissible spongiform encephalopathies

The levels of 2 arachidonic acid metabolites formed either by enzymatic activity of cyclooxygenase, i.e. prostaglandin E-2 (PGE(2)), or by free radical-catalyzed peroxrdation, i.e. F-2-isoprostane 8-epi-prostaglandin F-2 alpha (8-epi-PGF(2 alpha)), were measured in the CSF of subjects with sporadic and familial Creutzfeldt-Jakob disease (CJD) and in brain homogenates of scrapie-infected mice. The CSF levels of both metabolites were increased in sporadic CJD (n = 52) and familial CJD (n = 10) patients when compared with a group of patients with noninflammatory disorders. Similarly, PGE(2) and 8-epi-PGF(2 alpha) levels were higher in brain homogenates obtained from C57BL/6J mice infected with the ME7 scrapie strain than in brain homogenates from control animals. As PGE(2) is 1 of the most abundant prostaglandins released during inflammation and 8-epi-PGF(2 alpha) is a quantitative marker of lipid peroxidation, our results provide in vivo biochemical evidence for the occurrence of inflammation and oxidative stress in human and experimental transmissible spongiform encephalopathies (TSEs), a concept so far based mainly on histopathological and in vitro evidence. Interestingly, in sporadic CJD patients, high CSF levels of PGE(2), but not 8-epi-PGF(2 alpha), correlated with short survival time, suggesting that the inflammatory response correlates with the clinical duration of disease.