Israel Medical Association Journal

Background: Although exercise has been shown to improve mood and well-being, the precise mechanism remains unknown. Neurosteroids are important neuroactive molecules with demonstrated involvement in several neurophysiological and disease processes. Previous research has noted neurosteroid changes in dehydroepiandrosterone (DHEA) levels following exercise.



Objectives: To determine whether changes in DHEA levels are associated with mood improvement after exercise and whether there are any differences in the effects on younger and older individuals. 



Methods: Individuals ≤ 50 years of age or > 65 years of age were recruited for study participation. Before and after 30 minutes of a standardized cycling regimen, each patient provided a blood sample and completed a questionnaire on mood and well-being. 



Results: Findings confirmed a significant increase in DHEA levels post-exercise. A decrease in negative factors (fatigue, tension, depression, anger) and an increase in positive mood factors were noted. No difference in change of measures was noted between younger and older subjects. A positive correlation was noted between mood change and DHEA blood-level changes in older subjects. Among older males, DHEA appeared to be associated with mood change after exercise. 



Conclusions: While preliminary, findings indicate a possible association between mood improvement following exercise and DHEA blood level changes. Understanding the biological mechanisms of exercise-induced mood changes is critical to utilizing exercise as a treatment for mood disorders.

Background: The neurosteroids dehydroepiandrosterone (DHEA) and its sulfated metabolite (DHEAS) have been reported to possess neuroprotective as well as anti-tumoral activity in vitro and in vivo.

Objectives: To compare the effect of the two neurohor­mones on cell viability in primary whole-brain fetal mouse culture and isolated neuronal culture, as well as in a human neuroblastoma cell line (SK-N-SH).

Methods: Cell viability and cell proliferation were deter­mined with the neutral red and ³H-thymidine uptake methods, Apoptosis in propidium iodide-stained neuroblastoma cells was determined using flow cytometry.

Results: DHEA (1 nM-10 ìM) decreased the viability of selected primary neuronal cells (33-95% after 24 and 72 hours) but not of whole-brain cultured cells (neuron+glia). DHEAS did not significantly modify cell viability in either primary culture. In a human neuroblastoma cell line, DHEA (1 nM- 1 ìM) decreased ³H-thymidine uptake (30-60%) and cell viability (23-52%) after 24 hours. DHEAS did not significantly modify, or only slightly stimulated, cell viability and uptake of  ³H-thymidine (132% of controls). The combination of DHEA and DHEAS neutralized the toxic effect of DHEA in both primary neuronal culture and neuroblastoma cell line. Flow cytometric analysis of DNA fragmentation in neuroblastoma cells treated with 100 nM DHEA/DHEAS for 24 hours showed an increase in apoptotic events (31.9% and 26.3%. respec­tively, vs. control 2.54%).

Conclusions: Our results do not confirm a neuroprotective role for DHEA and suggest that DHEA and DHEAS have a differential role: DHEA possesses a neurotoxic (expressed only in isolated neurons) and anti-proliferative effect DHEAS demonstrates only a slight neuroprotective effect.
 

Background: DHEAS, the most abundant steroid secreted by the adrenal cortex, is suggested to have an important role in the development of immune reaction by activating T cell function and increasing antibody response, and has been tried as a vaccine adjuvant in elderly people.

Objectives: We examined the correlation between endogenous DHEAS and antibody response in the neonatal period by comparing the serum DHEAS levels with the amount of antibody response against hepatitis B vaccination in neonates.

Methods: Vaccine was administered to 12 healthy infants within 24 hours of birth (day 0), and blood specimens were obtained on days 0 and 30 for determination of anti-hepatitis B surface antibody concentration and DHEAS levels.

Results: DHEAS levels varied widely (range 0.38-3.70 μg/ml, mean±SD 2.14±0.98). While we could identify two groups of patients - those with high DHEAS levels (2.90±0.56) and those with lower levels (1.30±0.56) - there was no correlation between DHEAS levels and the antibody response to hepatitis B vaccine (γ=-0.05).

Conclusions: In neonates, antibody response to hepatitis B vaccine does not correlate with DHEAS serum levels. These results do not support the usage of DHEAS as a vaccine adjuvant in neonates.

__________________________________

DHEAS= dehydepiandrosterone sulphate