Angiotensin II Moderately Decreases Plasmodium Infection and Experimental Cerebral Malaria in Mice

PLoS One. 2015 Sep 16;10(9):e0138191. doi: 10.1371/journal.pone.0138191. eCollection 2015.

Abstract

Angiotensin II, a peptide hormone that regulates blood pressure, has been proposed as a protective factor against cerebral malaria based on a genetic analysis. In vitro studies have documented an inhibitory effect of angiotensin II on Plasmodium growth, while studies using chemical inhibitors of angiotensin II in mice showed protection against experimental cerebral malaria but not major effects on parasite growth. To determine whether the level of angiotensin II affects Plasmodium growth and/or disease outcome in malaria, elevated levels of angiotensin II were induced in mice by intradermal implantation of osmotic mini-pumps providing constant release of this hormone. Mice were then infected with P. berghei and monitored for parasitemia and incidence of cerebral malaria. Mice infused with angiotensin II showed decreased parasitemia seven days after infection. The development of experimental cerebral malaria was delayed and a moderate increase in survival was observed in mice with elevated angiotensin II, as confirmed by decreased number of cerebral hemorrhages compared to controls. The results presented here show for the first time the effect of elevated levels of angiotensin II in an in vivo model of malaria. The decreased pathogenesis observed in mice complements a previous human genetic study, reinforcing the hypothesis of a beneficial effect of angiotensin II in malaria.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II / pharmacology*
  • Animals
  • Disease Models, Animal*
  • Humans
  • Malaria / blood
  • Malaria / parasitology
  • Malaria / prevention & control*
  • Malaria, Cerebral / blood
  • Malaria, Cerebral / parasitology
  • Malaria, Cerebral / prevention & control*
  • Mice
  • Mice, Inbred C57BL
  • Parasitemia / blood
  • Parasitemia / parasitology
  • Parasitemia / prevention & control*
  • Plasmodium berghei / physiology*
  • Vasoconstrictor Agents / pharmacology

Substances

  • Vasoconstrictor Agents
  • Angiotensin II