High basal serum allopregnanolone levels in overweight girls

Circulating steroids and mood disorders in patients with polycystic ovary syndrome

Aberrant androgen metabolism is a characteristic feature of polycystic ovary syndrome (PCOS). Various androgens as well as their precursors and metabolites can accumulate in the blood of PCOS patients. Although these steroids include neuroactive steroids, such as allopregnanolone and androstenedione (Δ4A), it remains unknown whether altered blood steroid levels contribute to the high risk of mood disorders in PCOS. In this study, we measured blood levels of 11 steroids in 25 PCOS patients using liquid chromatography-tandem mass spectrometry and chemiluminescent enzyme immunoassay, and assessed the psychological status of these patients using the Hospital Anxiety and Depression Scale (HADS) questionnaire. We also examined age and the degree of metabolic abnormalities of each patient. Steroid values of the patients were compared to our previous data from 31 eumenorrheic women. As a result, 20 patients exhibited aberrant blood levels of one or more of the 11 tested steroids. In most cases, Δ4A and allopregnanolone levels were within or close to the reference ranges. Levels of four steroids were negatively correlated with patients' age, while no correlation was observed between steroid values and metabolic conditions. Seven patients showed high HADS scores. HADS scores were correlated with blood Δ4A levels even after stratifying by body mass indexes, but not with the levels of other steroids or clinical data. These results indicate that the high frequency of anxiety and depression in PCOS patients cannot be ascribed to altered blood levels of a specific steroid, although there may be a weak association between circulating Δ4A levels and psychological conditions of the patients.

GABAA receptor currents in the dorsal motor nucleus of the vagus in females: influence of ovarian cycle and 5α-reductase inhibition

The dorsal motor nucleus of the vagus (DMV) contains the preganglionic motor neurons important in the regulation of glucose homeostasis and gastrointestinal function. Despite the role of sex in the regulation of these processes, few studies examine the role of sex and/or ovarian cycle in the regulation of synaptic neurotransmission to the DMV. Since GABAergic neurotransmission is critical to normal DMV function, the present study used in vitro whole cell patch-clamping to investigate whether sex differences exist in GABAergic neurotransmission to DMV neurons. It additionally investigated whether the ovarian cycle plays a role in those sex differences. The frequency of phasic GABAA receptor-mediated inhibitory postsynaptic currents in DMV neurons from females was lower compared with males, and this effect was TTX sensitive and abolished by ovariectomy (OVX). Amplitudes of GABAergic currents (both phasic and tonic) were not different. However, females demonstrated significantly more variability in the amplitude of both phasic and tonic GABAA receptor currents. This difference was eliminated by OVX in females, suggesting that these differences were related to reproductive hormone levels. This was confirmed for GABAergic tonic currents by comparing females in two ovarian stages, estrus versus diestrus. Female mice in diestrus had larger tonic current amplitudes compared with those in estrus, and this increase was abolished after administration of a 5α-reductase inhibitor but not modulation of estrogen. Taken together, these findings demonstrate that DMV neurons undergo GABAA receptor activity plasticity as a function of sex and/or sex steroids.NEW & NOTEWORTHY Results show that GABAergic signaling in dorsal vagal motor neurons (DMV) demonstrates sex differences and fluctuates across the ovarian cycle in females. These findings are the first to demonstrate that female GABAA receptor activity in this brain region is modulated by 5α-reductase-dependent hormones. Since DMV activity is critical to both glucose and gastrointestinal homeostasis, these results suggest that sex hormones, including those synthesized by 5α-reductase, contribute to visceral, autonomic function related to these physiological processes.

The additive effect of allopregnanolone on ghrelin's orexigenic effect in rats

The progesterone metabolite, allopregnanolone (AlloP), is a GABA_A receptor modulating steroid and is known to have orexigenic and pro-obesity effects. The neurobiological mechanisms underpinning these effects are most likely due to enhanced GABAergic signaling in the lateral arcuate nucleus (ARC) and medial paraventricular nucleus (PVN) of the hypothalamus. Inspired by the finding that GABAergic signaling is also important for the orexigenic effects of the circulating hormone, ghrelin, we sought to determine the extent to which AlloP (one of the most potent endogenous GABA_A-receptor modulators) operates alongside ghrelin to enhance food intake. Male rats with ad libitum access to standard chow were injected intravenously with AlloP and/or ghrelin, alone or in combination. The intake of the standard chow was greater after AlloP 1 mg/kg together with ghrelin 30 μg/kg than with 30 μg/kg ghrelin alone. Food intake was also increased for the combined treatment of AlloP 0.5 mg/kg + ghrelin 10 μg/kg, AlloP 1 mg/kg + ghrelin 10 μg/kg, and AlloP 0.5 mg/kg + ghrelin 30 μg/kg. There was no significant difference in food intake between the two ghrelin doses or between the two doses of AlloP and the vehicle. In electrophysiological studies, physiologically relevant concentrations of AlloP prolonged the current decay time of spontaneous inhibitory post-synaptic current of dissociated cells of the ARC and PVN. We conclude that AlloP enhances the hyperphagic effect of ghrelin, findings of potential relevance for the hyperphagia associated with the luteal phase of the reproductive cycle.

Allopregnanolone and reproductive psychiatry: an overview

Psychiatric symptoms that coincide with reproductive transitions are related to changes in sex steroids, but studies show that this relationship is governed by individual women's vulnerability to change rather than by differences in level. There is growing interest in the role of allopregnanolone (ALLO), a 3-α reduced metabolite of progesterone and a strong allosteric modulator of the GABA_A receptor, in such symptoms, with enough evidence now across various times of reproductive transition to offer an overview of the role of this hormone in reproductive psychiatry. This review offers a brief overview, focusing on literature of the last 3 years, of the relationship between allopregnanolone and mood at menarche; in the menstrual cycle; in the peripartum; and in the menopausal transition. ALLO dysregulation is identified in all of these transitions and found to be associated with mood symptoms, although evidence of its exact role; its relationship to other systems; and directionality is not consistent.

Allopregnanolone involvement in feeding regulation, overeating and obesity

Obesity is strongly associated with ill health, primarily caused by consumption of excessive calories, and promoted (inter alia) by gamma-amino-butyric-acid (GABA) stimulating food intake by activating GABA_A receptors (primarily with α3 and α2 subunits) in the hypothalamic arcuate nucleus and paraventricular nucleus. Allopregnanolone is a potent positive GABA_A receptor modulating steroid (GAMS). As reviewed here, elevated allopregnanolone levels are associated with increases in food intake, preferences for energy-rich food, and obesity in humans and other mammals. In women with polycystic ovarian disease, high serum allopregnanolone concentrations are linked to uncontrolled eating, and perturbed sensitivity to allopregnanolone. Increases in weight during pregnancy also correlate with increases in allopregnanolone levels. Moreover, Prader-Willis syndrome is associated with massive overeating, absence of a GABA_A receptor (with compensatory >12-, >5- and >1.5-fold increases in α4, γ2, and α1, α3 subunits), and increases in the α4, βx, δ receptor subtype, which is highly sensitive to allopregnanolone. GABA and positive GABA-A receptor modulating steroids like allopregnanolone stimulates food intake and weight gain.

Allopregnanolone levels and depressive symptoms during pregnancy in relation to single nucleotide polymorphisms in the allopregnanolone synthesis pathway

Allopregnanolone, a neurosteroid whose levels rise throughout gestation, putatively stabilizes antenatal mood. The present study aimed to investigate associations of plasma allopregnanolone to antenatal depressive symptoms, as well as to genetic and obstetric factors. Allopregnanolone plasma levels from 284 pregnant women were measured around gestational week 18. Haplotype tag single nucleotide polymorphisms in the aldo-keto reductase family 1, members C2 and C4 (AKR1C2, AKR1C4), and steroid 5 alpha-reductase 1 and 2 (SRD5A1, and SRD5A2) genes were genotyped in a larger sample of pregnant women (n=1351). The Edinburgh Postnatal Depression Scale (EPDS) was administered via web-questionnaires in gestational weeks 17 and 32. Demographic and obstetric data was retrieved from web-questionnaires and medical records. There was no association between allopregnanolone levels and depressive symptoms. Furthermore, no associations between allopregnanolone level and synthesis pathway genotypes were found after accounting for multiple comparisons. However, exploratory analyses suggested that the women who were homozygous for the minor allele of the AKR1C2 polymorphism rs1937863 had nominally lower allopregnanolone levels and lower depression scores in gestational week 17, but also the highest increase in depression scores between week 17 and 32. Additionally, higher body mass index was associated with lower allopregnanolone levels. The results do not support second trimester plasma allopregnanolone as a mood stabilizing factor. However, we speculate that AKR1C2 variation may alter the susceptibility to depressive symptoms through effects on central allopregnanolone synthesis. Another implication of this study is that the relationship between neuroactive steroids and obesity in pregnancy deserves to be investigated.

Women with polycystic ovary syndrome have elevated serum concentrations of and altered GABA(A) receptor sensitivity to allopregnanolone

OBJECTIVE

Several studies have reported that γ-aminobutyric acid (GABA) ergic circuits are involved in the pathophysiology of polycystic ovary syndrome (PCOS). The progesterone metabolite allopregnanolone is a potent GABA(A) -receptor-modulating steroid, and patients may have increased concentrations of allopregnanolone or altered GABAA receptor sensitivity. We investigated both of these possibilities in this study.

PATIENTS

We enrolled 9 women with PCOS and 24 age-matched eumenorrhoeic controls, who were divided into two groups by body mass index (BMI) (16 normal weight and 8 overweight).

MEASUREMENTS

We investigated the effects of allopregnanolone injection on GABA(A) receptor sensitivity in both groups of women. All women received a single intravenous dose of allopregnanolone (0·050 mg/kg). GABA(A) receptor sensitivity was assessed with the saccadic eye velocity (SEV) over 30° (SEV30°), the SEV30°/allopregnanolone concentration ([Allo]) ratio, and sedation, which were measured together with serum allopregnanolone at intervals for 180 min after injection. The controls were tested in the follicular phase of the menstrual cycle.

RESULTS

Baseline allopregnanolone concentrations were higher in the PCOS women than in the normal-weight (P = 0·034) and overweight controls (P = 0·004). The allopregnanolone concentrations after injection were higher in the PCOS women (P = 0·006) and overweight controls (P = 0·037) than in the normal-weight controls. All groups showed a decline in the SEV30°/[Allo] ratio after injection. Allopregnanolone had a smaller effect on the SEV30°/[Allo] ratio in the overweight women (PCOS, P = 0·032; controls, P = 0·007) than in the normal-weight controls. The sedation score after allopregnanolone injection was lower in the PCOS patients than in the controls, but was not different between the two control groups.

CONCLUSIONS

PCOS women had elevated baseline allopregnanolone concentrations compared with follicular-phase controls. All overweight women (PCOS and controls) were less sensitive to allopregnanolone than normal-weight controls.

Effects of Roux-en-Y gastric bypass surgery on eating behaviour and allopregnanolone levels in obese women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with abnormal eating habits. We examined whether surgical treatment affected allopregnanolone levels and eating behaviour in nine women with PCOS who qualified for Rou-en-Y gastric bypass surgery. Blood samples were obtained to measure sex-hormone-binding globulin, total testosterone, progesterone, and allopregnanolone, and eating behaviour was evaluated using the Three-Factor Eating Questionnaire before surgery and at 6 and 12 months after surgery. Body mass index and total testosterone levels decreased, and progesterone and sex-hormone-binding globulin levels increased after bariatric surgery compared with pre-surgical values. In patients with anovulatory menstrual cycles, both the serum allopregnanolone level and the allopregnanolone/progesterone ratio were unchanged after surgery. The patients had high uncontrolled and emotional eating scores, and low cognitive restraint scores before surgery, and these scores had improved significantly at 6 and 12 months after surgery. The presurgical allopregnanolone levels were significantly correlated with uncontrolled eating. In conclusion, these results suggest that allopregnanolone appear to be part of the mechanism underlying the abnormal eating behaviour of obese PCOS patients by causing the loss of control over food intake. Roux-en-Y gastric bypass surgery can improve eating behaviour and clinical symptoms, and may facilitate weight loss in obese women with PCOS.

Differential responses of two related neurosteroids to methylphenidate based on ADHD subtype and the presence of depressive symptomatology

RATIONALE

Attention deficit with hyperactivity disorder is a neurodevelopmental disorder associated with alterations in the prefrontal cortex via dopaminergic and noradrenergic neurotransmission. Neurosteroids (e.g. allopregnanolone and dehydroepiandrosterone) modulate the release of multiple neurotransmitters.

OBJECTIVE

This study aims to determine the baseline concentrations and daily variations in allopregnanolone and dehydroepiandrosterone in children with attention deficit hyperactivity disorder (ADHD) and to determine the effect of chronic administration of methylphenidate on clinical symptoms and on the concentrations of these two neurosteroids.

METHODS

We included 148 children aged 5 to 14 years, subdivided into two groups: ADHD group (n = 107, with a diagnosis of ADHD (DSM-IV-TR criteria), further classified in subtypes by an "attention deficit and hyperactivity scale" and subgroups by the "Children's Depression Inventory") and a control group (n = 41). The clinical workup included blood samples that were drawn at 20:00 and 09:00 hours, at inclusion in both groups, and after 4.61 ± 2.29 months of treatment only in the ADHD group, for measurements for allopregnanolone and dehydroepiandrosterone. Factorial analysis, adjusted for age and gender, was performed by using Stata 12.0.

RESULTS

Methylphenidate induced the doubling of allopregnanolone levels in the predominantly inattentive ADHD patients without depressive symptoms (27.26 ± 12.90 vs. 12.67 ± 6.22 ng/ml, morning values). Although without statistical differences, baseline dehydroepiandrosterone levels were higher and slightly increased after methylphenidate in the ADHD subtype with depressive symptoms (7.74 ± 11.46 vs. 6.18 ± 5.99 ng/ml, in the morning), opposite to the lower baseline levels, and further decrease after methylphenidate in the inattentive subtype with depressive symptoms.

CONCLUSIONS

Different neurosteroids may have different baseline concentrations and differential responses to methylphenidate treatment as a function of ADHD subtype and subgroup. These differential responses may be a clinical marker of ADHD subtype and/or co-morbidities.

Accuracy of self-assessed Tanner staging against hormonal assessment of sexual maturation in overweight African-American children

AIM

To evaluate the accuracy of self-reported Tanner (SRT) staging against a proxy method of physician's assessment of sexual maturation, using pubertal hormones in overweight African-American (AA) children.

METHODS

Cross-sectional data from 196 children (113 girls, 83 boys) aged 9-11 years, who were 'overweight' (>85th and <95th percentile for age- and gender-matched BMI; n = 43) or 'obese' (>95th percentile; n = 153) were used. Children assessed their breast or genital and pubic hair development using standardized Tanner drawings representing different stages of sexual maturity. SRT data were compared to pubertal stage assessed by measuring fasting serum concentrations of luteinizing hormone (LH) in boys, and LH and estradiol (E2) in girls, which were used to stage children into pubertal stages 1-5.

RESULTS

SRT stages of genital and pubic hair assessments in boys, and breast and pubic hair assessments in girls, yielded 15-20% concordance (kappa statistic = 0.02-0.12) compared to their hormone-derived pubertal stages.

CONCLUSIONS

Among overweight AA 9-11 year-old children, self-assessment of Tanner staging did not accurately assess their pubertal development when compared to a hormone-derived pubertal assessment method.