Dehydroepiandrosterone: a modulator of cellular immunity and heat shock protein 70 production during polymicrobial sepsis.

OBJECTIVE

DHEA is an immunomodulatory steroid hormone that improves survival during systemic inflammation. A DHEA-induced modulation of heat shock protein response may be an alternative mechanism contributing to the beneficial effects of this hormone. We investigated the effect of DHEA administration on survival, cellular immune functions, and HSP-70 production in septic mice.

DESIGN AND SETTING

Randomized animal study, level I trauma center, university research laboratory.

SUBJECTS

Male NMRI mice.

INTERVENTIONS

Mice were subjected to sham operation (laparotomy, LAP) or sepsis (cecal ligation and puncture, CLP) with or without administration of either saline 0.9% (LAP, CLP) or 20 mg/kg DHEA subcutaneously (LAP/DHEA, CLP/DHEA). Survival was monitored over a 48-h period. Splenocyte apoptosis rate (AnnexinV binding), splenocyte proliferation ([3H]thymidine incorporation), TNF-alpha plasma concentration (ELISA), and HSP-70 concentration (ELISA) in tissue extracts from liver, lung, and spleen were monitored 48 h after onset of sepsis.

RESULTS

DHEA administration improved the survival of septic mice (78% vs. 50%). This effect was paralleled by increased splenocyte proliferation, decreased cellular apoptosis rate of splenocytes, and attenuation of TNF-alpha release. Furthermore, an increased HSP-70 concentration was observed in lungs and spleens of DHEA-treated septic animals.

CONCLUSIONS

DHEA-treatment decreased the mortality rate of septic mice. This was accompanied by improved cellular immune functions and an augmented heat shock response (HSP-70) of lungs and spleens. Further studies are required to demonstrate a direct relationship between the improved survival and the observed alterations in the immune system in DHEA-treated animals.