Altered Levels of Hypothalamic‐Pituitary‐Adrenocortical Axis Hormones in Baboons and Mice during the Course of Infection withSchistosoma mansoni

Abstract

Baboons with primary or secondary exposure to Schistosoma mansoni were compared with each other over a 12-week infection period and with baseline values obtained from uninfected baboons with respect to serum levels of the hypothalamic-pituitary-adrenal (HPA) axis hormones-corticotropin-releasing hormone, adrenocorticotropic hormone, dehydroepiandrosterone sulfate (DHEA-S), and cortisol. Baboons with primary infections, when worm recovery and oviposition rates were high and hepatic schistosome egg granulomas were large, had decreasing levels of these hormones as infection progressed, compared with both uninfected and reexposed baboons. The most reduced hormone level was that of DHEA-S. Reduction of DHEA-S and cortisol levels also occurred in primary murine infections. Reexposed baboons with low worm recovery and oviposition rates and small (modulated) hepatic granulomas showed the opposite pattern: HPA axis hormone levels were maintained at, or exceeded, the baseline values of uninfected baboons. These results suggest that HPA axis hormones may play a role in regulating the establishment, maturation, and oviposition of schistosomes and the progression of schistosomiasis.

Experimental models of Schistosoma mansoni infection

“…Decreased levels of corticotropin-releasing hormone, adrenocorticotropic hormone and dehydroepiandrosterone were reported by Morales-Montor et al (2001) in acutely infected baboons and mice but not in rechallenged chronically infected baboons. In baboons, but not mice, the lower hormone levels correlated with unmodulated granulomas.…”

Regulation of Granulomatous Inflammation in Experimental Models of Schistosomiasis

“…Serum levels of hypothalamic-pituitary-adrenal axis hormones, including corticotropin-releasing hormone, adrenocorticotropic hormone, dehydroepiandrosterone sulfate (DHEA-S), and cortisol, were assayed in S. mansoni-infected baboons for 12 weeks (98). During the primary infections the numbers of worms and eggs were high, and HG were large.…”

Influence of age of mice on the susceptibility to murine schistosomiasis infection

“…Baboons with primary infections (which had higher worm recovery and oviposition rates, and large hepatic egg granulomas) had decreasing levels of DHEA as infection progressed compared with uninfected or re-exposed baboons [6]. When cercariae, schistosomula and adult worms of S. mansoni were exposed in vitro to DHEA, cercariae were found to be more susceptible to damage by DHEA than schistosomula or adult worms [7]. Urinary schistosomiasis has been reported to cause delay in puberty in human males [8].…”