Inhibition of Plasmodium berghei Liver Schizont Development and Reduction of Cytokine Production Capacity in Rats by Dietary Fish Oil Supplementation

Experimental primary infection with Plasmodium berghei in rats is known to be influenced by several cytokines. Dietary supplementation of n-3 fatty acids has been shown to influence cytokine production capacity and to protect mice from cerebral malaria. We investigated the effect of dietary fish oil (FO) supplementation on cytokine and nitric oxide production and liver schizont development in male brown Norway rats. Control groups were fed either a corn oil-supplemented diet (CO) or standard lab chow (LC). After six weeks on either diet, rats given supplementary FO had a significantly lower production of interleukin-1 (IL-1) and IL-6 after stimulation with lipopolysaccharide, and also had significantly lower numbers of liver schizonts compared with CO- or LC-fed animals. We conclude that in rats, an FO-supplemented diet reduces the production capacity of IL-I and IL-6 and inhibits schizont development after intravenous inoculation of P. berghei sporozoites. Fish oil did not influence nitric oxide production by peritoneal macrophages.