Hypothalamic pituitary gonadal axis dysregulation in depressed women

Preconception depression reduces fertility: a couple-based prospective preconception cohort

STUDY QUESTION

Is preconception depression associated with time to pregnancy (TTP) and infertility?

SUMMARY ANSWER

Couples with preconception depression needed a longer time to become pregnant and exhibited an increased risk of infertility.

WHAT IS KNOWN ALREADY

Preconception depression in women contributes to impaired fertility in clinical populations. However, evidence from the general population-especially based on couples-is relatively scant.

STUDY DESIGN SIZE DURATION

A couple-based prospective preconception cohort study was performed in 16 premarital examination centers between April 2019 and June 2021. The final analysis included 16 521 couples who tried to conceive for ≤6 months at enrollment. Patients with infertility were defined as those with a TTP ≥12 months and those who conceived through ART.

PARTICIPANTS/MATERIALS SETTING METHODS

Couples' depression was assessed using the Patient Health Questionnaire-9 at baseline. Reproductive outcomes were obtained via telephone at 6 and 12 months after enrollment. Fertility odds ratios (FORs) and infertility risk ratios (RRs) in different preconception depression groups were analyzed using the Cox proportional-hazard models and logistic regression, respectively.

MAIN RESULTS AND THE ROLE OF CHANCE

Of the 16 521 couples analyzed, 10 834 (65.6%) and 746 (4.5%) couples achieved pregnancy within the first 6 months and between the 6th and 12th months, respectively. The median (P25, P75) TTP was 3.0 (2.0, 6.0) months. The infertility rate was 13.01%. After adjusting for potential confounders, in the individual-specific analyses, we found that preconception depression in women was significantly related to reduced odds of fertility (FOR = 0.947, 95% CI: 0.908-0.988), and preconception depression in either men or women was associated with an increased risk of infertility (women: RR = 1.212, 95% CI: 1.076-1.366; men: RR = 1.214, 95% CI: 1.068-1.381); in the couple-based analyses, we found that-compared to couples where neither partner had depression-the couples where both partners had depression exhibited reduced fertility (adjusted FOR = 0.904, 95% CI: 0.838-0.975). The risk of infertility in the group where only the woman had depression and both partners had depression increased by 17.8% (RR = 1.178, 95% CI: 1.026-1.353) and 46.9% (RR = 1.469, 95% CI: 1.203-1.793), respectively.

LIMITATIONS REASONS FOR CAUTION

Reporting and recall bias were unavoidable in this large epidemiological study. Some residual confounding factors-such as the use of anti-depressants and other medications, sexual habits, and prior depressive and anxiety symptoms-remain unaddressed. We used a cut-off score of 5 to define depression, which is lower than prior studies. Finally, we assessed depression only at baseline, therefore we could not detect effects of temporal changes in depression on fertility.

WIDER IMPLICATIONS OF THE FINDINGS

This couple-based study indicated that preconception depression in individuals and couples negatively impacts couples' fertility. Early detection and intervention of depression to improve fertility should focus on both sexes.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by grants from the National Natural Science Foundation of China (No. 82273638) and the National Key Research and Development Program of China (No. 2018YFC1004201). All authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Changes in Psychotropic Drug Concentrations Across the Menstrual Cycle: A Pilot Study

BACKGROUND

The escalating prescription of psychopharmacological medications to women of reproductive age underscores the growing significance of sex-specific variations in pharmacotherapy. Despite this, clinical trials have largely overlooked these differences. Preliminary data indicate sex-specific variations in the neurobiology of affective disorders and in the metabolism, pharmacodynamics, and kinetics of therapeutic drugs. This underscores the imperative for a more nuanced exploration of menstrual cycle-dependent fluctuations in psychotropic drugs. This pilot study aimed to investigate drug and hormone fluctuations in female patients with affective disorders, aiming to enhance comprehension of the interplay between cycle-related hormone fluctuations and pharmacokinetics. The ultimate goal is to facilitate more effective and safer pharmacological therapy in the future.

METHODS

Blood samples were collected from 27 patients and 27 age-matched control participants at 3 distinct time points (early follicular phase, ovulation, and late luteal phase) during each menstrual cycle. Depressive and manic symptoms were assessed, and hormone concentrations were measured in the entire sample, while drug concentrations were assessed solely in the affective disorder sample using mass spectrometry.

RESULTS

Significant variations in drug concentration were observed throughout the menstrual cycle for bupropion, with a trend toward altered concentration for venlafaxine. Moreover, notable differences in hormone concentrations were identified between patients and controls, even after accounting for the impact of contraceptive use, diagnoses, and medication.

CONCLUSIONS

This pilot study reinforces previously reported data, underscoring the significance of sex-specific pharmacological therapy approaches. It provides further evidence supporting the interaction among sex hormones, drugs, and symptoms of affective disorders.

Association between testosterone levels and mood disorders: A minireview

BACKGROUND

Although many studies reported the neuropsychiatric involvement of testosterone (T) levels in the development of mood disorders, its role in this disabling disorder is still not well understood. Therefore, in this review, we aim to summarize the current literature exploring serum testosterone levels in both major depressive disorder (MDD) and bipolar disorder (BD), with particular attention given to the possible causal relationship between pathological mood alterations and T levels.

METHODS

We selected 9 original studies from a bibliographic search on PubMed, excluding studies on hormonal therapy and other psychiatric disorders other than mood disorders.

RESULTS

The results reported by the reviewed studies were conflicting especially with regards to the presence of dysfunctional levels of T in patients with BD. Specifically, while MDD was found to be associated with low levels of T compared to healthy controls (HC), in BD the results were highly heterogeneous, with a mixed picture of reduced, increased or no difference in T levels in BD patients compared to HC.

LIMITATIONS

Studies were highly heterogeneous in terms of samples employed, psychometric scales used for assessing depressive symptoms, T assay methods and therapeutic regimens.

CONCLUSIONS

Overall, T levels were shown to be reduced in both MDD and BD patients, ultimately suggesting that T could be useful as a biomarker in mood disorders and provide guidance for future research.

Self-reported menstrual cycle length during reproductive years in relation to menopausal symptoms at midlife in Project Viva

OBJECTIVE

The aim of this study was to investigate the extent to which self-reported menstrual cycle length during reproductive years is associated with menopausal symptoms and age at natural menopause at midlife.

METHODS

This analysis includes 634 women who enrolled in Project Viva during pregnancy (1999-2002) and completed the midlife visit approximately 18 years later. Women self-reported menstrual cycle length at enrollment (early pregnancy) and at midlife reported total and specific menopausal symptoms using the Menopause Rating Scale as well as age at natural menopause. We used linear and regression models to evaluate associations of cycle length with total and specific menopausal symptoms. We also applied a time-to-event Cox proportional hazards model to investigate the relationship between menstrual cycle length and onset of natural menopause. We adjusted models for age at midlife visit, prepregnancy body mass index, race/ethnicity, education, and parity.

RESULTS

At enrollment (median age, 33.3 years), 90 (14%) women reported having short (≤25 days) and 39 (6%) reported long (≥35 days) menstrual cycles. Compared with women with a normal menstrual cycle length of 26 to 34 days, women whose cycles were short had a higher total Menopause Rating Scale at midlife ( β = 2.05; 95% confidence interval [CI], 0.73-3.38). Specifically, women with short menstrual cycles during their reproductive years had higher odds of midlife sleep problems (odds ratio [OR], 1.92; 95% CI, 1.10-3.37), heart discomfort (OR, 1.68; 95% CI, 1.03-2.73), and depressive symptoms (OR, 1.85; 95% CI, 1.16-2.96). In addition, compared with women with a normal cycle length of 26 to 34 days, women reporting short cycles had an earlier onset of natural menopause (hazard ratio, 1.67; 95% CI, 1.11-2.51).

CONCLUSIONS

Compared with women with normal menstrual cycle length, those with short menstrual cycles during their reproductive years had a higher frequency of total and certain menopausal symptoms at midlife and reached menopause earlier.

Increased inhibitory activity in the basolateral amygdala and decreased anxiety during estrus: A potential role for ASIC1a channels

The amygdala is central to emotional behavior, and the excitability level of the basolateral nucleus of the amygdala (BLA) is associated with the level of anxiety. The excitability of neuronal networks is significantly controlled by GABAergic inhibition. Here, we investigated whether GABAergic inhibition in the BLA is altered during the rat estrous cycle. In rat amygdala slices, most principal BLA neurons display spontaneous IPSCs (sIPSCs) in the form of "bursts" of inhibitory currents, occurring rhythmically at a frequency of about 0.5 Hz. The percentage of BLA neurons displaying sIPSC bursts, along with the inhibitory charge transferred by sIPSCs and the frequency of sIPSC bursts, were significantly increased during the estrus phase; increased inhibition was accompanied by reduced anxiety in the open field, the light-dark box, and the acoustic startle response tests. sIPSC bursts were blocked by ibuprofen, an antagonist of acid-sensing-1a channels (ASIC1a), whose activity is known to increase by decreasing temperature. A transient reduction in the temperature of the slice medium, strengthened the sIPSCs bursts; this effect was blocked in the presence of ibuprofen. Further analysis of the sIPSC bursts during estrus showed significantly stronger rhythmic inhibitory activity in early estrus, when body temperature drops, compared with late estrus. To the extent that these results may relate to humans, it is suggested that "a calmer amygdala" due to increased inhibitory activity may underlie the positive affect in women around ovulation time. ASIC1a may contribute to increased inhibition, with their activity facilitated by the body-temperature drop preceding ovulation.

No Correlation between Blood Benzene Levels and Luteinizing Hormone Plasma Values in Outdoor Workers

OBJECTIVE

The purpose of the study is to evaluate whether low-dose exposure to benzene, an environmental pollutant to which male and female traffic policemen are daily exposed to could cause alterations in plasma luteinizing hormone (LH) levels.

METHODS

From an initial sample of 1594 workers, we only selected 95 workers of whom study we knew the values of late-shift benzene and LH hormone. All subjects underwent biological monitoring (final blood benzene evaluation) and luteinizing hormone dosing. Excluding subjects with the main confounding factors, the final sample included 76 workers. The normal distribution of the variables was evaluated using the Kolmogorov - Smirnov test, followed by the logarithmic transformation of the LH and benzene values. The comparison among means was performed by using the t-test for the independent samples. The ANOVA test was performed for variables with more than 2 modes (ages and seniority) and Pearson correlation index between variables in the total sample and after subdivision as to sex, job, sports activity and smoking. The results were considered significant when p values were less than 0.05.

RESULTS/CONCLUSION

The study did not show a correlation between benzene levels and LH plasma levels in outdoor workers.

Comparison of affect changes during the ovulatory phase in women with and without hormonal contraceptives

Studies about affect changes during the menstrual cycle and the role of hormones in these changes have yielded contradictory results. Often research has focused on the pre-menstrual phase, with few studies paying specific attention to the affect changes around ovulation. In this research thirty women completed a daily questionnaire measuring the positive and negative affect during their menstrual cycle. These women were divided in two groups: hormonally-contracepting and naturally-cycling. The Positive and Negative Affect Schedule was used to measure the affect. A Digital Ovulation Test was used to determine the day of ovulation in the participants not taking hormonal contraceptives by measuring the Luteinizing Hormone peak. The differences in positive affect (PA) and negative affect (NA) between groups were examined. The results indicate that during the ovulatory phase, PA scores are significantly higher in naturally-cycling women than hormonally-contracepting women.

The influence of the HPG axis on stress response and depressive-like behaviour in a transgenic mouse model of Huntington's disease

Huntington's disease (HD) is an autosomal dominant, neurodegenerative disease caused by a CAG tandem repeat mutation encoding a polyglutamine tract expansion in the huntingtin protein. Depression is among the most common affective symptoms in HD but the pathophysiology is unclear. We have previously discovered sexually dimorphic depressive-like behaviours in the R6/1 transgenic mouse model of HD at a pre-motor symptomatic age. Interestingly, only female R6/1 mice display this phenotype. Sexual dimorphism has not been explored in the human HD population despite the well-established knowledge that the clinical depression rate in females is almost twice that of males. Female susceptibility suggests a role of sex hormones, which have been shown to modulate stress response. There is evidence suggesting that the gonads are adversely affected in HD patients, which could alter sex hormone levels. The present study examined the role sex hormones play on stress response in the R6/1 mouse model of HD, in particular, its modulatory effect on the hypothalamic-pituitary-adrenal (HPA) axis and depression-like behaviour. We found that the gonads of female R6/1 mice show atrophy at an early age. Expression levels of gonadotropin-releasing hormone (GnRH) were decreased in the hypothalamus of female HD mice, relative to wild-type female littermates, as were serum testosterone levels. Female serum estradiol levels were not significantly changed. Gonadectomy surgery reduced HPA-axis activity in female mice but had no effect on behavioural phenotypes. Furthermore, expression of the oestrogen receptor (ER) α gene was found to be higher in the adrenal cells of female HD mice. Finally, administration of an ERβ agonist diarylpropionitrile (DPN) rescued depressive-like behaviour in the female HD mice. Our findings provide new insight into the pathogenesis of sexually dimorphic neuroendocrine, physiological and behavioural endophenotypes in HD, and suggest a new avenue for therapeutic intervention.

First manic episode associated with use of human chorionic gonadotropin for obesity: a case report

BACKGROUND

Although highly controversial, the treatment of obesity with exogenous human chorionic gonadotropin (HCG) remains popular in the USA. We report the case of a patient whose first manic episode was associated with the use of HCG for weight loss.

CASE REPORT

A 32-year-old female patient was admitted to our psychiatric inpatient unit due to a two-week history of manic symptoms. She had no previous history of manic or hypomanic episodes and had completed a 45-day course of sublingual HCG for weight loss immediately prior to the onset of the manic episode. The patient was treated with lithium carbonate and aripiprazole, and progressed with improvement in the symptoms.

CONCLUSION

While it is not possible to definitively link the HCG use to the development of mania, available evidence suggests that HCG may have a contributing role in triggering manic symptomatology.

Disruption of fetal hormonal programming (prenatal stress) implicates shared risk for sex differences in depression and cardiovascular disease

Comorbidity of major depressive disorder (MDD) and cardiovascular disease (CVD) represents the fourth leading cause of morbidity and mortality worldwide, and women have a two times greater risk than men. Thus understanding the pathophysiology has widespread implications for attenuation and prevention of disease burden. We suggest that sex-dependent MDD-CVD comorbidity may result from alterations in fetal programming consequent to the prenatal maternal environments that produce excess glucocorticoids, which then drive sex-dependent developmental alterations of the fetal hypothalamic-pituitary-adrenal (HPA) axis circuitry impacting mood, stress regulation, autonomic nervous system (ANS), and the vasculature in adulthood. Evidence is consistent with the hypothesis that disruptions of pathways associated with gamma aminobutyric acid (GABA) in neuronal and vascular development and growth factors have critical roles in key developmental periods and adult responses to injury in heart and brain. Understanding the potential fetal origins of these sex differences will contribute to development of novel sex-dependent therapeutics.

Stress, depression, and coronary artery disease: modeling comorbidity in female primates

Depression and coronary heart disease (CHD) are leading contributors to disease burden in women. CHD and depression are comorbid; whether they have common etiology or depression causes CHD is unclear. The underlying pathology of CHD, coronary artery atherosclerosis (CAA), is present decades before CHD, and the temporal relationship between depression and CAA is unclear. The evidence of involvement of depression in early CAA in cynomolgus monkeys, an established model of CAA and depression, is summarized. Like people, monkeys may respond to the stress of low social status with depressive behavior accompanied by perturbations in hypothalamic-pituitary-adrenal (HPA), autonomic nervous system, lipid metabolism, ovarian, and neural serotonergic system function, all of which are associated with exacerbated CAA. The primate data are consistent with the hypothesis that depression may cause CAA, and also with the hypothesis that CAA and depression may be the result of social stress. More study is needed to discriminate between these two possibilities. The primate data paint a compelling picture of depression as a whole-body disease.

Mood disorders and fertility in women: a critical review of the literature and implications for future research

A medline literature review of fertility and mood disorder articles published since 1980 was performed in order to critically review the literature regarding a relationship between mood disorders, fertility and infertility treatment. Previous studies suggests that mood disorders, both in the bipolar and unipolar spectrum, may be associated with decreased fertility rates. Most studies report that women seeking treatment for infertility have an increased rate of depressive symptoms and possibly major depression (none showed evaluated mood elevations). Many, but not all, studies found that depressive symptoms may decrease the success rate of fertility treatment. Treatments for infertility may independently influence mood through their effects on estrogen and progesterone, which have been shown to influence mood through their actions on serotonin. Studies are limited in scope and confounding variables are many, limiting the strength of the results. In conclusion, a range of existing studies suggests that fertility and mood disorders are related in a complex way. Future studies should use clinical interviews and standardized and validated measures to confirm the diagnosis of mood disorders and control for the variables of medication treatment, desire for children, frequency of sexual intercourse, age, FSH levels, menstrual cycle regularity in assessing an interrelationship between mood disorders and fertility.

Hypothalamic-pituitary-end organ function in women with bipolar depression

Disturbance of each of the three hypothalamic-pituitary-end organ systems [hypothalamic-pituitary-thyroid (HPT), -adrenal (HPA), and -gonadal (HPG)] has been reported in depressive disorders. Little is known about potential reciprocal interaction among the three HP-end organ systems in patients with depressive disorders. The present pilot study examined selective HPA and HPG hormones in a detailed time series in women with bipolar disorder (depressed type) before and after treatment with levothyroxine (L-T4), and in matched control subjects. Six medically stable, euthyroid, premenopausal women with bipolar depression, and 5 age-matched controls underwent overnight blood sampling from 2100 to 0900 h for measurement of adrenocorticotropic hormone (ACTH), cortisol, luteinizing hormone (LH), and estradiol every 15 min. Bipolar patients underwent a second overnight blood sampling procedure following 7-weeks of open-label add-on treatment with L-T4. Results revealed lower baseline cortisol parameters in bipolar patients in comparison to control subjects, while ACTH, LH, and estradiol parameters were similar. Thyroid hormones (TSH, free and total T4) were not correlated with any of the HPA or HPG hormones. ACTH and cortisol levels were correlated in control subjects, but not in bipolar patients. After L-T4 treatment, thyroid hormones increased significantly and depression scores significantly declined. No significant changes in HPA or HPG hormones parameters were observed, although the small sample size may have limited results. Upon visual inspection, ACTH and cortisol appeared to decrease after L-T4 treatment, while estradiol appeared to increase. These pilot data suggest lower levels of cortisol in women with bipolar depression, unlike previously published studies that reported higher cortisol in patients with depression. The data also suggest reciprocal changes in the HPA and HPG axes upon pharmacological modulation of the HPT system, although whether this change was due to the L-T4 treatment or the improvement of depression is unknown. The results are preliminary, and require replication in larger samples.

Role of androgens and glucocorticoids in the regulation of diazepam-binding inhibitor mRNA levels in male mouse hypothalamus

In peripheral organs, gonadal and adrenal steroids regulate diazepam-binding inhibitor (DBI) mRNA expression. In order to further investigate the involvement of peripheral steroid hormones in the modulation of brain DBI mRNA expression, we studied by semiquantitative in situ hybridization the effect of adrenalectomy (ADX) and castration (CX) and short-term replacement therapy on DBI mRNA levels in the male mouse hypothalamus. Cells expressing DBI mRNA were mostly observed in the arcuate nucleus, the median eminence and the ependyma bordering the third ventricle. In the median eminence and the ependyma bordering the third ventricule, the DBI gene expression was decreased in ADX rats and a single injection of corticosterone to ADX rats induced a significant increase in DBI gene expression at 3 and 12 h time intervals without completely restoring the basal DBI mRNA expression observed in intact mice. In the arcuate nucleus, ADX and corticosterone administration did not modify DBI mRNA expression. CX down-regulated DBI gene expression in the ependyma bordering the third ventricle. The administration of dihydrotestosterone (3-24 h) completely reversed the inhibitory effect of CX. In the median eminence and arcuate nucleus, neither CX or dihydrotestosterone administration modified DBI mRNA levels. These results suggest that the effects of glucocorticoids on the hypothalamo-pituitary-adrenocortical axis and androgens on the hypothalamo-pituitary-gonadal axis are mediated by DBI.

Homeostatic regulation of sleep in a genetic model of depression in the mouse: effects of muscarinic and 5-HT1A receptor activation

In depressed patients, sleep undergoes marked alterations, especially sleep onset insomnia, sleep fragmentation, and disturbances of the Rapid Eye Movement (REM) sleep. Abnormalities of rest-activity rhythms and of hypothalamic-pituitary-adrenocortical function have also been described in these patients. In the present study, we examined the presence of such abnormalities in a recently developed line of mice (Helpless mice-H) that exhibit depression-like behaviors in validated tests, compared to the nonhelpless (NH) line derived from the same colony. Experiments were essentially carried out in females for which previous studies showed marked differences between H and NH lines. Compared to NH mice, the H line exhibited (i) lower basal locomotor activity, (ii) sleep fragmentation, shift towards lighter sleep stages, and facilitation of REM sleep reflected by increased amounts and decreased latency, (iii) larger response to the REM sleep promoting effect of muscarinic receptor stimulation (by arecoline). In contrast, H and NH mice were equally responsive to the REM sleep inhibitory effect of 5-HT1A receptor stimulation (by 8-OH-DPAT). In addition, a deficiency in delta power enhancement after sleep deprivation was observed in the H group, and acute immobilization stress in this group failed to elicit a REM sleep rebound and was associated with a long-lasting raise in serum corticosterone levels. These results further validate H mice as a depression model and suggest they might be of particular interest for investigating the neurobiological mechanisms and possibly genetic substrates underlying sleep alterations associated with depression.

Ovarian dysfunction in peripubertal hyperinsulinemia

OBJECTIVE

Increasing evidence suggests that hyperinsulinemia plays an important role in the pathogenesis of polycystic ovary syndrome (PCOS). However, the timing for the onset of hyperinsulinemia is not clear. The objective of this study was to examine the effect of peripubertal hyperinsulinemia on the maturing female reproductive axis.

METHODS

Hyperinsulinemia was induced in 28-day-old peripubertal female rats by infusing insulin (0.04 IU/d) via subcutaneously implanted Alzet minipumps (Model #2004; Durect Corp, Cupertino, CA; constant flow rate 0.25 muL/h) for 4 weeks. Control animals were administered normal saline. Estrus cyclicity was monitored regularly. Upon termination of the experimental period, the animals were killed, trunk blood and pituitaries were collected for hormone assays, and ovaries were collected for histological and immunocytochemical studies.

RESULTS

In contrast to the control animals, hyperinsulinemic animals had (1) erratic estrus cycles, with prolonged (2 to 3 days) metestrus-diestrus or diestrus-proestrus stages; (2) significantly (P <.05) decreased levels of serum progesterone, and significantly (P <.05) increased levels of serum testosterone and dehydroepiandrostene sulfate; (3) prematurely luteinized ovarian follicles with prominent thecal and interfollicular stromal proliferation; and (4) markedly reduced expression of growth differentiation factor-9 (GDF-9) and activin receptors (ActR) I and IB in the ovaries.

CONCLUSION

Peripubertal hyperinsulinemia in rats causes hormonal and ovarian changes similar to those in women with PCOS. Based on these novel findings, we speculate that peripubertal hyperinsulinemia may be a risk factor for the development of PCOS later in life.

Exposure to urban stressor and effects on luteinizing hormone (LH) in female outdoor workers

There are few studies in literature about exposure to urban pollutants and effects on female reproductive health. The aim of the study was to evaluate if the occupational exposure to chemical urban stressor could cause luteinizing hormone (LH) plasma levels alterations in female traffic police compared to a control group. One hundred and eighty subjects were included in the study, subdivided into three different groups according to the day of the menstrual cycle (7th, 14th, 21st) in which a blood sample was taken. In follicular and lutheal phase of ovarian cycle, the LH mean levels were significantly higher in traffic police vs. controls. The distribution of LH values in traffic police and controls was significant in follicular, and lutheal phase. In ovulatory phase, LH mean levels were lower but not significant in traffic police compared to controls. An increase was found concerning mental health disorders referred to the questionnaire items in traffic police vs. controls, although the difference was not significant. Our results suggest that occupational exposure to urban stressor in female traffic police, may alter LH plasma concentrations. LH may be used in occupational set as an early biomarker of exposure to urban stressor.

Adverse effects of methylphenidate on the reproductive axis of adolescent female rats

OBJECTIVE

To examine the effects of chronic methylphenidate use on the reproductive axis of adolescent female rats.

DESIGN

Controlled prospective study.

SETTING

University research laboratory.

ANIMAL(S)

Twenty prepubertal female Sprague Dawley rats.

INTERVENTION(S)

Subcutaneous implantation of drug-filled Alzet minipumps (Durect Corporation, Cupertino, CA) for infusing methylphenidate (450 microg/d, treated) or physiological saline (control) for 4 weeks. Estrous cyclicity was checked from 3 weeks of pump implantation till the termination of the experiments. Animals were killed after 4 weeks of treatment.

MAIN OUTCOME MEASURE(S)

Estrous cyclicity, pituitary and peripheral FSH and LH, serum estrogen and progesterone, ovarian histology, and immunocytochemistry for localizing growth differentiation factor-9 and activin receptors-I.

RESULT(S)

Compared with the control group, the treated animals exhibited the following: [1] poor vaginal opening and erratic estrous cyclicity; [2] undeveloped, disrupted, or prematurely luteinized ovarian follicles; [3] absence of growth differentiation factor-9 and of activin receptors I and IB in the oocyte; and [4] high levels of LH in the pituitary.

CONCLUSION(S)

Chronic methylphenidate administration during adolescence perturbs pubertal onset, adversely affects maturation of the female reproductive axis by retarding pituitary LH release, and adversely affects ovarian folliculogenesis. These novel findings may have significant clinical implications in evaluating the effects of methylphenidate abuse on adolescent health.

The stress system in the human brain in depression and neurodegeneration

Corticotropin-releasing hormone (CRH) plays a central role in the regulation of the hypothalamic-pituitary-adrenal (HPA)-axis, i.e., the final common pathway in the stress response. The action of CRH on ACTH release is strongly potentiated by vasopressin, that is co-produced in increasing amounts when the hypothalamic paraventricular neurons are chronically activated. Whereas vasopressin stimulates ACTH release in humans, oxytocin inhibits it. ACTH release results in the release of corticosteroids from the adrenal that, subsequently, through mineralocorticoid and glucocorticoid receptors, exert negative feedback on, among other things, the hippocampus, the pituitary and the hypothalamus. The most important glucocorticoid in humans is cortisol, present in higher levels in women than in men. During aging, the activation of the CRH neurons is modest compared to the extra activation observed in Alzheimer's disease (AD) and the even stronger increase in major depression. The HPA-axis is hyperactive in depression, due to genetic factors or due to aversive stimuli that may occur during early development or adult life. At least five interacting hypothalamic peptidergic systems are involved in the symptoms of major depression. Increased production of vasopressin in depression does not only occur in neurons that colocalize CRH, but also in neurons of the supraoptic nucleus (SON), which may lead to increased plasma levels of vasopressin, that have been related to an enhanced suicide risk. The increased activity of oxytocin neurons in the paraventricular nucleus (PVN) may be related to the eating disorders in depression. The suprachiasmatic nucleus (SCN), i.e., the biological clock of the brain, shows lower vasopressin production and a smaller circadian amplitude in depression, which may explain the sleeping problems in this disorder and may contribute to the strong CRH activation. The hypothalamo-pituitary thyroid (HPT)-axis is inhibited in depression. These hypothalamic peptidergic systems, i.e., the HPA-axis, the SCN, the SON and the HPT-axis, have many interactions with aminergic systems that are also implicated in depression. CRH neurons are strongly activated in depressed patients, and so is their HPA-axis, at all levels, but the individual variability is large. It is hypothesized that particularly a subgroup of CRH neurons that projects into the brain is activated in depression and induces the symptoms of this disorder. On the other hand, there is also a lot of evidence for a direct involvement of glucocorticoids in the etiology and symptoms of depression. Although there is a close association between cerebrospinal fluid (CSF) levels of CRH and alterations in the HPA-axis in depression, much of the CRH in CSF is likely to be derived from sources other than the PVN. Furthermore, a close interaction between the HPA-axis and the hypothalamic-pituitary-gonadal (HPG)-axis exists. Organizing effects during fetal life as well as activating effects of sex hormones on the HPA-axis have been reported. Such mechanisms may be a basis for the higher prevalence of mood disorders in women as compared to men. In addition, the stress system is affected by changing levels of sex hormones, as found, e.g., in the premenstrual period, ante- and postpartum, during the transition phase to the menopause and during the use of oral contraceptives. In depressed women, plasma levels of estrogen are usually lower and plasma levels of androgens are increased, while testosterone levels are decreased in depressed men. This is explained by the fact that both in depressed males and females the HPA-axis is increased in activity, parallel to a diminished HPG-axis, while the major source of androgens in women is the adrenal, whereas in men it is the testes. It is speculated, however, that in the etiology of depression the relative levels of sex hormones play a more important role than their absolute levels. Sex hormone replacement therapy indeed seems to improve mood in elderly people and AD patients. Studies of rats have shown that high levels of cumulative corticosteroid exposure and rather extreme chronic stress induce neuronal damage that selectively affects hippocampal structure. Studies performed under less extreme circumstances have so far provided conflicting data. The corticosteroid neurotoxicity hypothesis that evolved as a result of these initial observations is, however, not supported by clinical and experimental observations. In a few recent postmortem studies in patients treated with corticosteroids and patients who had been seriously and chronically depressed no indications for AD neuropathology, massive cell loss, or loss of plasticity could be found, while the incidence of apoptosis was extremely rare and only seen outside regions expected to be at risk for steroid overexposure. In addition, various recent experimental studies using good stereological methods failed to find massive cell loss in the hippocampus following exposure to stress or steroids, but rather showed adaptive and reversible changes in structural parameters after stress. Thus, the HPA-axis in AD is only moderately activated, possibly due to the initial (primary) hippocampal degeneration in this condition. There are no convincing arguments to presume a causal, primary role for cortisol in the pathogenesis of AD. Although cortisol and CRH may well be causally involved in the signs and symptoms of depression, there is so far no evidence for any major irreversible damage in the human hippocampus in this disorder.

Gonadotropin-releasing hormone-stimulated gonadotropin levels in women with premenstrual dysphoria

Despite consistent evidence that premenstrual dysphoria (PMD) is not characterized by abnormalities in basal ovarian hormone secretion, the possibility remains that PMD is associated with an abnormality in the regulation of the hypothalamic-pituitary-ovarian (HPO) axis. We studied HPO axis regulation in 11 women with prospectively confirmed PMD and 20 asymptomatic controls, during both the follicular and luteal phases of the menstrual cycle. Plasma levels of the gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), were obtained before and after stimulation with gonadotropin-releasing hormone (GnRH) (100 microg intravenously). Potential diagnostic- and menstrual cycle phase-related diferences in basal and plasma hormone levels were analyzed by repeated-measures analysis of variance. No significant differences were observed between women with PMD and controls in either basal or stimulated levels of FSH and LH. Stimulated FSH was significantly increased and stimulated LH was significantly decreased during the follicular compared with the luteal phase in both women with PMD and controls. These data are consistent with prior findings of normal basal reproductive hormone levels in women with PMD. Our data suggest the absence in women with PMD of an abnormality of dynamic ovarian function as measured by GnRH stimulation.

Pulsatile luteinizing hormone disruption in depression

Two independent groups recently published data comparing pulsatile luteinizing hormone (LH) release between depressed and control women. Despite similar populations and LH sampling frequency, they reached different conclusions: Meller et al. [Am. J. Psych. 154 (1997) 1454] found disruption of normal LH pulsatility in depressed women, whereas Young et al. [Arch. Gen. Psych. 57 (2000) 1157] did not. To resolve this discrepancy, the current study applies a single, well-established statistical method, spectral analysis, to the two data sets and concludes that both depressed populations display significantly altered LH pulsatile release.

In vivo action of a new octadecaneuropeptide (ODN) antagonist on gonadotropin-releasing hormone gene expression in the male rat brain

It has been reported that several of the effects induced by octadecaneuropeptide (ODN) could be mediated by an activation of a metabotropic receptor. In order to investigate the role and mechanism of action of ODN in gonadotropin-releasing hormone (GnRH) neuron regulation, we studied the effects of the acute i.c.v. administration of ODN and of a new ODN antagonist to metabotropic receptor, cyclo(1-8)[Dleu(5)]OP, on GnRH mRNA expression as evaluated by in situ hybridization in castrated male rats. The administration of ODN produced a decrease in the hybridization signal while the administration of cyclo(1-8)[Dleu(5)]OP alone produced an 18% increase. When administrated concomitantly with ODN, the antagonist both inhibited the depressing effect of ODN and induced a 22% increase over the values detected in ODN-treated rats. The data suggest that the effect of ODN on GnRH mRNA expression might be mediated by interaction with metabotropic receptors.

Treatment of depression with the CRH-1-receptor antagonist R121919: endocrine changes and side effects

A dysregulation of the hypothalamus-pituitary-adrenocortical (HPA) system has been hypothesized to account for a myriad of cardinal symptoms of affective disorders. Specifically, increased CRH signalling via CRH type 1 receptors is thought to be an important factor in the pathogenesis of major depression and anxiety disorders. Consequently, a number of drugs have been developed in order to target the postulated increase in CRH/CRH 1 receptor signalling. One of these compounds, R121919, binds with high affinity to CRH1 receptors antagonising the action of CRH. R121919 was recently tested in an open-label study conceptualized as a safety and tolerability study. As part of this study, a thorough endocrine evaluation and detailed clinical laboratory analysis were assessed several times during 30 days of treatment with two different dose regimens of R121919 (5-40 mg vs. 40-80 mg) in 24 patients with a major depressive episode. During treatment with the experimental drug no serious side effects were noted. In particular, there were no adverse effects or impairment of the hypothalamic-pituitary-gonadal system, the hypothalamic-pituitary-thyroid axis, the renin-angiotensin system, prolactin or vasopressin secretion. Furthermore, no changes in the serum corticotropin and cortisol concentrations and in the responsivity of corticotropin and cortisol following a CRH stimulation test were noted. No effects of R121919 on clinical laboratory parameters including liver enzymes, EEG and ECG were observed. These results encourage the development of other CRH-1-R antagonists as a novel class of antidepressive drugs.

Luteinizing hormone following light exposure in healthy young men

Urinary luteinizing hormone (LH) and the melatonin metabolite (6-sulfatoxymelatonin; aMT6s) were measured in normal young men following early morning light exposure. Eleven young healthy men ages 19-30 years participated in this study. During separate weeks in counterbalanced order, each subject received both 5 days of bright light treatment (BL) and 5 days of placebo light treatment (PL) for 1 h (05:00-06:00). LH excretion was increased 69.5% after bright light exposure, but was not changed by placebo light exposure. The acrophases and offsets of aMT6s were advanced, but the duration of aMT6s excretion was not changed after BL. Light stimulation of LH could have interesting applications in psychiatry and reproductive endocrinology.

Gender differences in the efficacy of fluoxetine and maprotiline in depressed patients: a double-blind trial of antidepressants with serotonergic or norepinephrinergic reuptake inhibition profile

BACKGROUND

Depression has emerged as a contrastive area of gender differences in psychiatry, as epidemiological data has consistently shown depression is twice as common in women as men. The pharmacodynamic effect of antidepressants may also show gender differences, as suggested by reports of better response of young women to non-tricyclic antidepressants.

METHODS

The antidepressive effect of an SSRI (fluoxetine) and a tetracyclic antidepressant with selective norepinephrine reuptake inhibitory effect (maprotiline) was compared in a 6-week, double-blind trial of 105 depressed patients.

RESULTS

No significant difference was observed in the change of HAMD17 total score from baseline to week 6 between fluoxetine- and maprotiline-treated patients. A significant difference was observed in females (fluoxetine, -17.8; maprotiline, -13.9; P=0.017) between treatment groups, but not in males. Amongst females, the difference was significant in women aged <44 years (fluoxetine, -18.4; maprotiline, -12.9; P=0.023) but not > or =44 years.

CONCLUSIONS

Females in their reproductive period are more responsive to SSRI (fluoxetine) than norepinephrinergic tetracyclic antidepressant (maprotiline) treatment. Normal cyclical ovulation, and estrogen release may have a clinically relevant pharmacodynamic interaction with serotonergic antidepressants.