Elevated central nervous system prostaglandins in human immunodeficiency virus—associated dementia

The dementia associated with human immunodeficiency virus (HIV) is poorly understood. Dementia is accompanied by infection and activation of macrophage lineage cells in the brain and production of toxic products by these cells has been postulated to play a role in the pathogenesis of dementia. Eicosanoids are potential products of activated macrophages that can mediate cell injury. We measured the levels of prostaglandin E₂ in the cerebrospinal fluid of HIV‐positive individuals with dementia and/or myelopathy and compared these levels with those of HIV‐negative patients with other neurological diseases and HIV‐positive patients without dementia. Cerebrospinal fluid prostaglandin E₂ levels were increased in dementia. This increase was associated with severity of dementia and correlated with cerebrospinal fluid levels of neopterin and β₂‐microglobulin. Prostaglandins F_2α and thromboxane B₂, additional products of the cyclooxygenase pathway of arachidonic acid metabolism, were also elevated in dementia, but leukotriene C₄, a product of the lipoxygenase pathway was not. Since synthesis of prostaglandins is regulated in part by the levels of inducible forms of cyclooxygenase, we measured the levels of cyclooxygenase‐1 and 2 mRNAs in the brains of HIV‐positive individuals with and without dementia by reverse transcriptase polymerase chain reaction. Levels of intact cyclooxygenase‐1 mRNA were higher in the brains of demented individuals, but this did not reach statistical significance. These data demonstrate that prostaglandins are increased in the central nervous system in HIV‐associated dementia and may play a role in the development of neurological dysfunction.