Suppression of prostaglandin E2 by malaria parasite products and antipyretics promotes overproduction of tumor necrosis factor-alpha: association with the pathogenesis of childhood malarial anemia.

Published

Journal Article

Cytokines and effector molecules are important immunoregulatory molecules in human malaria. Tumor necrosis factor (TNF)-alpha limits malaria parasitemia but also promotes pathogenesis at high concentrations, whereas prostaglandin E2 (PGE2) inhibits TNF-alpha production and is reduced in childhood malaria, at least in part, through suppression of cyclooxygenase (COX)-2 following the ingestion of Plasmodium falciparum hemozoin (pfHz; malarial pigment) by peripheral blood mononuclear cells (PBMCs). Although molecular interactions between TNF-alpha and PGE2 are largely unexplored in human malaria, results presented here show that pfHz-induced suppression of PBMC COX-2 gene products induces overproduction of TNF-alpha. Moreover, addition of exogenous PGE2 to pfHz-treated PBMCs dose-dependently decreased TNF-alpha production, whereas experimental COX inhibitors and antipyretics used during human malaria generated increased TNF-alpha production. Healthy, malaria-exposed children had elevated levels of circulating bicyclo-PGE2/TNF-alpha, compared with children with malarial anemia (P<.01), with systemic bicyclo-PGE2 and TNF-alpha significantly associated with hemoglobin concentrations (r=0.745; P<.01). The results of the present study illustrate that pfHz-induced suppression of PGE2 promotes overproduction of TNF-alpha, which is associated with enhanced malarial anemia.

Full Text

Duke Authors

Cited Authors

  • Keller, CC; Davenport, GC; Dickman, KR; Hittner, JB; Kaplan, SS; Weinberg, JB; Kremsner, PG; Perkins, DJ

Published Date

  • May 2006

Published In

Volume / Issue

  • 193 / 10

Start / End Page

  • 1384 - 1393

PubMed ID

  • 16619186

Pubmed Central ID

  • 16619186

Electronic International Standard Serial Number (EISSN)

  • 1537-6613

International Standard Serial Number (ISSN)

  • 0022-1899

Digital Object Identifier (DOI)

  • 10.1086/503047

Language

  • eng