Cortisol, prolactin, cytokines and the susceptibility of pregnant Sudanese women to Plasmodium falciparum malaria

Abstract

Understanding the hormonal and cytokine interactions that underlie susceptibility to the disease should be helpful in elucidating the pathogenesis of malaria during pregnancy. The current study was conducted in the Wad Medani hospital, in an area of central Sudan that is characterised by unstable malarial transmission. Its aims were to investigate the roles and interactions of cortisol, prolactin, interferon-γ (IFN-γ), interleukin-4 (IL-4) and interleukin-10 (IL-10) in pregnant women with Plasmodium falciparum malaria. The 82 pregnant subjects who were enrolled either had uncomplicated, P. falciparum malaria (the 47 cases) or were apparently uninfected and healthy women (the 37 controls) who were similar to the cases in terms of their mean age, weight, gravidity, gestational age and haemoglobin concentration.

Compared with the controls, the cases were found to have significantly higher serum concentrations of total cortisol and IL-10 and significantly lower levels of prolactin and IFN-γ (but similar concentrations of IL-4). The hormone and cytokine concentrations measured in the infected primigravidae were similar to those recorded in the infected multigravidae.

Among the cases, there was a significant positive correlation between serum cortisol and IL-10 (r=0.188; P=0.025) and significant negative correlations between prolactin and both IL-4 (r=−0.175; P=0.038) and IL-10 (r=−0.186; P=0.027) but no significant correlation between prolactin and cortisol.

During pregnancy, immune responses appear to be influenced by P. falciparum infections, irrespective of parity. Cortisol, prolactin and some cytokines appear to be key mediators in the host response to P. ?falciparum infection, although further research on this subject is clearly needed.