Any facts behind the DHEA hype?

Dehydroepiandrosterone and alpha-estradiol limit the functional alterations of rat brain mitochondria submitted to different experimental stresses

The effects of dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA-S), alpha-estradiol and beta-estradiol on the main functions of purified rat brain mitochondria were investigated in basal conditions and after being submitted to various stresses including anoxia-reoxygenation, uncoupling and apoptosis. In basal conditions, DHEA (1 microM) and alpha-estradiol (1 microM) inhibited the respiratory control ratio (RCR) from 3.1 to 2.3 (25%). After anoxia-reoxygenation, DHEA (1 microM) and alpha-estradiol (1 microM) reversed significantly (P<0.01) the RCR decrease from 1.4 to 2.0 (21.5%) by restoring the state 4. This effect was observed when DHEA was added either before anoxia or before reoxygenation and when alpha-estradiol was added before anoxia. The mitochondrial membranes damaged after the anoxia-reoxygenation were 70 and 50%, respectively, protected by DHEA and alpha-estradiol at 1 microM. They also limited by about 50%, the cytochrome c release induced by the anoxia-reoxygenation. The oxygen consumption of mitochondria in presence of NADH (130 microM) and cytochrome c (5 microM) was significantly inhibited by DHEA and alpha-estradiol with high EC(50) of 30 and 22 pM, respectively. At 1 microM, they also inhibited the 10 microM carbonyl cyanide m-chlorophenylhydrazone-induced uncoupling to about 35% whereas beta-estradiol only decreased it to 9%. Our results indicated that DHEA and alpha-estradiol partly preserved the mitochondrial functions altered by an anoxia-reoxygenation with a concentration-dependent effect. The mechanism involved was independent of the classical genomic effect of steroids, the antioxidant properties but implicated a direct action on the mitochondrial membranes.

Dehydroepiandrosterone sulphate prevents oxygen-glucose deprivation-induced injury in cerebellar granule cell culture

Decreased levels of dehydroepiandrosterone sulphate have been hypothesized to contribute to increased vulnerability of the ageing or stressed human brain to ischemia. To help to address the question of whether of dehydroepiandrosterone sulphate has a possible neuroprotective effect against ischemic neuronal injury, we tested its effect on the neurodegeneration induced by oxygen-glucose deprivation in rat cultured cerebellar granule cells. Dehydroepiandrosterone sulphate added to the medium after injury demonstrated a neuroprotective effect with a median inhibitory concentration of 0.5 microM. At 10 microM concentration almost full neuroprotection was observed. Even more pronounced neuroprotective effect was found when dehydroepiandrosterone sulphate was added for 48h before injury. Furthermore, partial neuroprotection of dehydroepiandrosterone sulphate was also found against 1-methyl-4-phenylpyridinium, colchicine, glutamate and N-methyl-D-aspartate-induced toxicity. Further analysis demonstrated that dehydroepiandrosterone sulphate eliminated the apoptotic features of the oxygen-glucose deprivation-induced neuronal death: DNA fragmentation and nuclear condensation/fragmentation.Thus, our data suggest that dehydroepiandrosterone sulphate may have therapeutic potential in the prevention and treatment of ischemic/hypoxic neuronal damage. The neuroprotective action of dehydroepiandrosterone sulphate was inhibited by both a GABA(A) receptor-linked chloride channel agonist and an antagonist, pentobarbital and picrotoxin, respectively. It seems that GABA(A) receptor-mediated neuronal inhibition as well as neuronal excitation can reduce the neuroprotective action of dehydroepiandrosterone sulphate.

Dehydroepiandrosterone (DHEA) reduces neuronal injury in a rat model of global cerebral ischemia

INTRODUCTION

Many studies report an inverse correlation between levels of DHEA and neurological diseases. Exogenous DHEA protects hippocampal neurons against excitatory amino acid induced neurotoxicity. The purpose of this experiment is to evaluate the effect of DHEA in an animal model of transient but severe forebrain ischemia.

METHODS

At thirteen days prior to induction of ischemia, male Wistar rats were implanted with various doses of DHEA-placebo, 25 mg, 50 mg or 100 mg. Forebrain ischemia was induced for 10 min using a modified four-vessel occlusion technique, with hippocampal neuronal injury assessed at 7 days post-ischemically and expressed as a percentage of total cells.

RESULTS

Both normal and necrotic hippocampal CA(1) cells were counted. Percentages of hippocampal injury observed were 88+/-13% in animals treated with placebo, 84+/-8% in the 25 mg DHEA group, and 60+/-7% in the 50 mg DHEA group. Animals treated with 100 mg DHEA displayed a significant (P<0.05) reduction of hippocampal CA(1) cell injury at 60+/-7%

CONCLUSION

Treatment with a high dose, but not a low or moderate dose, of DHEA implantation reduces hippocampal CA(1) neuronal injury following severe but transient forebrain ischemia.

Relationships among cortisol (CRT), dehydroepiandrosterone-sulfate (DHEAS), and memory in a longitudinal study of healthy elderly men and women

At test times 18 months apart (Time 1 and Time 2), men (n Time 1 = 31, Time 2 = 23), women estrogen-users (n Time 1 = 14, Time 2 = 10), and women estrogen non-users (n Time 1 = 41, Time 2 = 27), whose average age was 72.1 and 73.4 years at Time 1 and Time 2, respectively, were tested with a battery of neuropsychological tests measuring verbal memory, visual memory, concentration/attention, language fluency and semantic memory. Plasma levels of CRT and DHEAS were assayed by radioimmunoassay at both test times. The men had higher DHEAS levels than both groups of women at both test times (p < 0.001) and also had a higher DHEAS/CRT ratio compared to the estrogen non-users (p < 0.05). Although there were no group differences in CRT levels at either time, CRT levels increased in the estrogen non-using women from Time 1 to Time 2 (p < 0.001). Subjects with lower CRT levels performed better than those with higher levels on several tests of declarative memory (p < 0.05). Men and estrogen-users had higher Digit Span scores compared to female estrogen non-users at both test times (p < 0.01), and women estrogen-users also had higher Backward Digit Span scores than non-users (p < 0.05). Both groups of women performed better than men on Category Retrieval (p < 0.01). These findings suggest that higher CRT levels in elderly men and women are associated with poorer explicit memory functioning; however, these results failed to provide any evidence that DHEAS is protective against declarative memory decline with aging.

Dehydroepiandrosterone (DHEA) protects hippocampal cells from oxidative stress-induced damage

It has been postulated that decreases in plasma levels of dehydroepiandrosterone (DHEA) may contribute to the development of some age-related disorders. Along with neuroprotective and memory enhancing effects, DHEA has been shown to display antioxidant properties. Moreover, oxidative stress is known to cause lipid peroxidation and degenerative changes in the hippocampus, an area involved in memory processes and especially afflicted in Alzheimer's disease (AD). Accordingly, we investigated the antioxidant effects of DHEA in models of oxidative stress using rat primary hippocampal cells and human hippocampal tissue from AD patients and age-matched controls. A pre-treatment of rat primary mixed hippocampal cell cultures with DHEA (10-100 microM) protected against the toxicity induced by H2O2 and sodium nitroprusside. Moreover, DHEA (10-100 microM) was also able to prevent H2O2/FeSO4-stimulated lipid oxidation in both control and AD hippocampal tissues. Taken together, these data suggest that DHEA may be useful in treating age-related central nervous system diseases based on its protective effects in the hippocampus.

Possible dihydroepiandrosterone-induced mania

BACKGROUND

Dehydroepiandrosterone (DHEA) is among the most abundant steroids in the human body and appears to have diverse biochemical activities. This multifunctional hormone has long been a compound of interest to research psychiatrists. Its recent promotion and availability as an over-the-counter supplement to the general public has led to widespread use. Little is known about potential adverse effects of DHEA when consumed on an acute or chronic basis. We report a case of mania in an older man acutely admitted to our psychiatric facility with no previous personal or family history of bipolar disorder that appeared to be related to recent DHEA use. The patient had initiated DHEA use 6 months prior to admission and was taking 200-300 mg/day at the time of presentation.

METHODS

He was treated with valproic acid 500 mg twice daily.

RESULTS

The patient showed sufficient improvement to be discharged following a 7-day inpatient hospitalization.

CONCLUSIONS

A wide range of medications have been associated with the induction of hypomania and mania, and we have provided a brief discussion of the potential for DHEA to trigger manic symptoms.