Does sex hormone treatment reverse the sex-dependent stress regulation? A longitudinal study on hypothalamus-pituitary-adrenal (HPA) axis activity in transgender individuals

Sexual function of transgender assigned female at birth seeking gender affirming care: a narrative review

Sexual health is pivotal to the overall health and well-being of individuals. To date, transgender persons' sexual function results to be poorly investigated. Gender affirming medical and/or surgical treatments (GAMSTs) in transgender assigned female at birth (t-AFAB) can have an impact on overall quality of life and subsequently on sexual life. Before GAMSTs, literature shows a low sexual wellbeing of t-AFAB due to a complex interaction of organic and psychological factors. During gender affirming hormone therapy, testosterone treatments induce virilization that results in a better sexual satisfaction, in particular for sexual desire, arousal and orgasm. The majority of the available literature reports an increased sexual quality of life among t-AFAB after gender affirming surgery. Nevertheless, the different surgical techniques, the possible post-operative complications and sexual pain can negatively influence sexual function. Thus, this narrative review aims to summarize the available data about modifications on sexual health status in t-AFAB before and after GAMSTs. In transgender population, dealing with the evaluation of sexual life and satisfaction represents a relevant topic with a view to promote and sustain not only sexual wellbeing but especially general quality of life.

Gender minority stress and diurnal cortisol profiles among transgender and gender diverse people in the United States

The field of behavioral neuroendocrinology has only begun to explore the lived experiences of transgender and gender diverse (TGD) people exposed to stigma. In light of escalating attacks and legislation targeting TGD people in the United States, it is crucial to examine the physiological pathways through which gender minority stressors become embodied, impact health, and contribute to health inequities. The Trans Resilience and Health Study included baseline data collection from fall 2019 to spring 2020 from a sample of 124 TGD people, reflecting a diversity of gender identities (e.g., trans masculine, trans feminine, and nonbinary) and ages (range = 19-70 years old; M = 34.10), living in Michigan, Nebraska, Oregon, and Tennessee. These analyses examine experiences of gender-related enacted stigma in association with hypothalamic-pituitary-adrenal (HPA)-axis functioning. Among those experiencing the highest levels of enacted stigma, findings show a blunted cortisol awakening response and sluggish daily decline that resulted in elevated concentrations at bedtime compared to those experiencing less enacted stigma. These results of flattened diurnal activity are consistent with an emergent literature on discrimination as a social determinant of potential stress pathophysiology. In contrast, community connectedness was associated with a larger, more dynamic cortisol awakening response. These findings emphasize the importance of incorporating gender-minority stress and resilience measures when studying HPA-axis functioning among TGD people.

Gender-affirming hormone therapy effect on cortisol levels in trans males and trans females

PURPOSE

Previous studies have shown differences in baseline and stimulated cortisol levels between men and women. Whether this difference is secondary to sex hormones or to other factors, such as genetic or epigenetic changes, is unknown. We investigated the effect of gender-affirming hormone treatment (GAHT) on the hypothalamo-pituitary-adrenal axis of transgender subjects in an effort to throw light on this question.

METHODS

Ten transgender males (TM) and eight transgender females (TF) underwent a low-dose (1 µg) adrenocorticotropic hormone (ACTH) stimulation test before and 6 months after GAHT initiation. Serum total, free and salivary cortisol (SC) levels were measured at baseline and at 20, 30 and 40 min.

RESULTS

For the TM, all three levels were significantly lower at several time points after ACTH injection compared to pretreatment levels following 6 months of treatment (p < .05). Likewise, the overall SC response as calculated by the area under the curve was significantly lower (p = .0053). For the TF, the basal total cortisol (TC) level increased after 6 months of treatment (p < .01) while ACTH-stimulated SC levels decreased significantly. The basal ACTH levels were significantly lower following hormonal therapy (p < .001).

CONCLUSION

Stimulated salivary cortisol levels decreased significantly after 6 months of GAHT in both male and female transgender subjects, possibly reflecting a decreased state of anxiety associated with treatment initiation. Additionally, basal and stimulated serum TC levels increased after hormonal treatment in the TF, probably secondary to the effect of oestrogen on cortisol-binding globulin.

The effect of short-term increase of estradiol levels on sexual desire and orgasm frequency in women and men: A double-blind, randomized, placebo-controlled trial

Estradiol (E2) has been implicated in sexual functioning in both sexes. E2 levels change distinctively over the menstrual cycle, peaking around ovulation. Data on short-term effects of fluctuating E2 levels on sexual desire are however sparse and mostly based on observational studies. To fill this gap, we ran a double-blind, randomized, placebo-controlled study (N = 126) to investigate the effects of a short-term increase in E2 on sexual desire and orgasm frequency in healthy, young men and women. Circulating E2 levels were elevated through estradiol valerate (E2V) administered over two consecutive days to simulate the rise in E2 levels around ovulation. E2V had no effect on orgasm frequency and only minor effects on sexual desire. On average, the administered E2V dampened change in sexual desire compared to untreated participants with comparable baseline sexual desire in such a way that sexual desire was slightly reduced even in those with higher baseline sexual desire. These findings suggest that short-term increases in E2 have little effect on sexual function and are unlikely to explain the increase in sexual desire around ovulation.

Gender Dysphoria in Young People: A Model of Chronic Stress

BACKGROUND

Gender dysphoria (GD) refers to the distress that may accompany gender incongruence, often heightened at the onset of puberty, with the development of secondary sex characteristics. Children and adolescents may be especially vulnerable to severe stressors, including GD, with potentially irreversible effects if these exposures occur during critical periods of development and brain maturation.

SUMMARY

We describe the evidence for GD as a chronic stressor, drawing parallels to other established models of stress, activating both innate psychological and biological stress responses. As well as being an inherently distressing experience, a person who experiences GD may also experience minority stress. Minority stress has been demonstrated in young people who experience GD with higher rates of social rejection and internalized stigma and shame. The biological stress response in young people with GD is illustrated through the activation of the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and pro-inflammatory response. The number of young people who report experiencing GD has increased exponentially worldwide in the past decade, demanding a change in the clinic infrastructure. Paediatric endocrinologists and specialists in mental health work together to both support psychosocial well-being and offer individualized treatment to align the phenotype with gender identity with the aim of alleviating the distress of GD. Medical interventions may include puberty suppression and gender-affirming hormones. Ongoing monitoring is required prior to initiation and during treatment to ensure that the goals of treatment are being achieved.

Effects of circulating estradiol on physiological, behavioural, and subjective correlates of anxiety: A double-blind, randomized, placebo-controlled trial

Anxiety-related behaviours as well as the prevalence of anxiety disorders show a large sex difference in humans. Clinical studies in humans as well as behavioural studies in rodents suggest that estradiol may have anxiolytic properties. In line with this, anxiety symptoms fluctuate with estradiol levels along the menstrual cycle. However, the influence of estradiol on subjective, behavioural, as well as physiological correlates of anxiety has never been systematically addressed in humans. We ran a double-blind, randomized, placebo-controlled study (N = 126) to investigate the effects of estradiol on anxiety in men and women. In healthy volunteers, circulating estradiol levels were elevated through estradiol administration over two consecutive days to simulate the rise in estradiol levels around ovulation. Subjective, behavioral, as well as, physiological correlates of anxiety were assessed using a virtual reality elevated plus-maze (EPM). Estradiol treatment reduced the physiological stress response with blunted heart rate response and lower cortisol levels compared to placebo treatment in both sexes. In contrast, respiration frequency was only reduced in women after estradiol treatment. Behavioural measures of anxiety as well as subjective anxiety on the EPM were not affected by estradiol treatment. In general, women showed more avoidance and less approach behavior and reported higher subjective anxiety levels on the EPM than men. These results highlight the limited anxiolytic properties of circulating levels of estradiol in humans, which influence physiological markers of anxiety but not approach and avoidance behaviour or subjective anxiety levels.

Stressing the need for validated measures of cortisol in HIV research: A scoping review

OBJECTIVES

People living with HIV experience numerous endocrine abnormalities and psychosocial stressors. However, interactions between HIV, cortisol levels, and health outcomes have not been well described among people living with HIV on effective therapy. Furthermore, methods for measuring cortisol are disparate across studies. We describe the literature reporting cortisol levels in people living with HIV, describe methods to measure cortisol, and explore how this relates to health outcomes.

METHODS

We searched the PubMed database for articles published in the past 20 years regarding HIV and cortisol with ≥50% of participants on antiretroviral therapies. Articles included observational, case-control, cross-sectional, and randomized controlled trials analyzing cortisol by any method. Studies were excluded if abnormal cortisol was due to medications or other infections. Variables were extracted from selected studies and their quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

In total, 19 articles were selected and included, covering the prevalence of abnormal cortisol (n = 4), exercise (n = 4), metabolic syndrome and/or cardiovascular disease (n = 2), mental health and cognition (n = 9), and sex/gender (n = 6). Cortisol was measured in serum (n = 7), saliva (n = 8), urine (n = 2), and hair (n = 3) specimens. Comparisons between people with and without HIV were inconsistent, with some evidence that people with HIV have increased rates of hypocortisolism. Depression and cognitive decline may be associated with cortisol excess, whereas anxiety and metabolic disease may be related to low cortisol; more data are needed to confirm these relationships.

CONCLUSIONS

Data on cortisol levels in the era of antiretroviral therapy remain sparse. Future studies should include controls without HIV, appropriately timed sample collection, and consideration of sex/gender and psychosocial factors.

Cardiovascular Health of Youth During Gender-Affirming Testosterone Treatment: A Review

PURPOSE

Many birth-assigned female/transgender male and nonbinary people (identified as masculine spectrum here) begin gender-affirming testosterone therapy by the age of 24 years. Few data inform assessment of cardiovascular health of masculine spectrum youth as a specific subgroup of the 1.5 million transgender people in the United States. The purpose of this review is to help youth-serving practitioners consider, understand, and evaluate cardiovascular health in adolescent and young adult masculine spectrum patients receiving gender-affirming testosterone treatment.

METHODS

This is a narrative review intended to synthesize a broad body of clinical and research literature.

RESULTS

Common cardiovascular health changes associated with testosterone include increased red blood cell mass and likely insignificant changes in high-density lipoprotein and low-density lipoprotein levels. Changes in heart mass, heart electrophysiology, and endothelial reactivity are likely, based on extrapolation of data from adults. Testosterone may have indirect effects on cardiovascular health through influences on depression, anxiety, stress, and anorexia nervosa as well as on behaviors such as tobacco use.

CONCLUSIONS

Testosterone contributes importantly to the cardiovascular health and well-being of masculine spectrum gender-diverse youth. We need to do a better job of supporting these young people with data on cardiovascular health over the life span.

The gonadal response to social stress and its relationship to cortisol

The cortisol response to social evaluative stress has been well characterized. However, data regarding changes in gonadal hormones after stress are still scarce and inconsistent. The majority of studies have focused on testosterone reactivity to stress in men, while estradiol responses or gonadal stress responses in women have hardly been investigated. Furthermore, it has not been evaluated whether sex hormone reactivity to stress differs between men and women and the relationship between cortisol and gonadal reactivity to stress is still unclear. To address these questions, we re-analyzed saliva samples collected from 37 men and 30 women in their luteal cycle phase before and repeatedly after social-evaluative stress. Both, testosterone and estradiol levels were assessed. In both men and women, testosterone was significantly reduced after stress. Testosterone levels were at their lowest after 20 minutes, but did not return to baseline until 35 minutes after stress. Across the whole sample, estradiol was significantly increased after stress with two separate peaks after 15 and 30 minutes. Follow-up analyses revealed that 41 participants actually responded with a decrease in estradiol levels to stress, with lowest levels after 20 min, while the remaining participants responded with an increase in estradiol levels. These gonadal stress responses appear to be largely independent of the cortisol response to stress. These results demonstrate that the endocrinological stress response is not restricted to the HPA axis and stress responsivity of gonadal hormones is not simply driven by cortisol. Accordingly, the stress responsivity of gonadal hormones and their association to psychological variables is an additional avenue to explore in both men and women.

New Insights Into Extended Steroid Hormone Profiles in Transwomen in a Multi-Center Setting in Germany

BACKGROUND

Little information is available on steroid hormone profiles in transwomen on the day of gender affirming surgery (GAS) after gender affirming hormone therapy (GAHT).

AIM

We compared extended serum steroid hormone profiles of 77 transwomen with 3 different treatment regimens in order to get more insight on how GAHT changes the hormone system.

METHODS

Samples were obtained from 3 independent clinics. Individuals in clinic A (n = 13) and B (n = 51) discontinued GAHT 4-6 weeks and 2 weeks before GAS, individuals in clinic C (n = 13) continued treatment. Testicular tissue, blood samples and questionnaires on age, weight, height, and medication use were received from each patient. Steroid hormones were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS), 6 sex hormones were determined by immunofluorometric assays, and ELISA. Spermatogenesis was scored using the Bergman/Kliesch score.

OUTCOMES

Participants were not different with regard to age, BMI, treatment duration, and dosage. Feminized blood serum levels with low LH, low FSH and low testosterone, however, were achieved in persons taking GAHT until GAS. Significantly reduced cortisone levels were seen after stopping GAHT before GAS.

RESULTS

GAHT had marked effects on the sex-steroid profile in each person. Factor analysis provided a model explaining 78% of the variance and interdependency of sex steroid levels. Stopping treatment was inversely associated with intactness of the corticosteroid-axis with adrenal steroidogenesis as well as it was inversely associated with pituitary-gonadal hormone production.

CLINICAL IMPLICATIONS

Transwomen generally did not have elevated cortisone levels but differed significantly depending on and when GAHT was stopped.

STRENGTHS & LIMITATIONS

This is the first study examining the steroid hormone profiles of transgender persons on the day of GAS in a multi-center setting. Additional studies (including follow ups before and after GAS and stress questionnaires) will be necessary to assess these conflicting results about the possible psychological impact on persons undergoing GAS to improve care.

CONCLUSION

Concerning feminized blood serum levels, continued GAHT seems the better alternative, however stopping treatment 4-6 weeks prior to surgery was associated with reduced cortisone levels. Schneider F, Wistuba J, Holterhus P-M, et al. New Insights Into Extended Steroid Hormone Profiles in Transwomen in a Multi-Center Setting in Germany. J Sex Med 2021;18:1807-1817.

Testosterone treatment, internalizing symptoms, and body image dissatisfaction in transgender boys

OBJECTIVE

Many transgender adolescents experience clinically elevated anxiety and depression. Testosterone (T), used as a gender affirming treatment, may reduce symptoms of anxiety and depression. We assessed the effect of gender affirming T treatment on internalizing symptoms, body image dissatisfaction, and activation patterns within the amygdala-prefrontal cortex circuit in transgender adolescent boys.

METHOD

Symptoms of generalized anxiety, social anxiety, depression, suicidality and body image dissatisfaction were measured by self-report and brain activation was measured during a face processing task with functional MRI in a group of 19 adolescent transgender boys receiving T treatment and 23 not receiving gonadal hormone treatment (UT).

RESULTS

Severity of anxiety and depression was significantly lower in the T treated group relative to the UT group, along with a trend of lower suicidality. The T group also reported less distress with body features and exhibited stronger connectivity within the amygdala-prefrontal cortex circuit compared to the UT group. Finally, group differences on depression and suicidality were directly associated with body image dissatisfaction, and anxiety symptoms were moderated by amygdala-prefrontal cortex connectivity differences between groups.

CONCLUSION

T treatment is associated with lower levels of internalizing symptoms among transgender adolescent boys. T is also associated with greater body satisfaction and greater connectivity in a neural circuit associated with anxiety and depression. Satisfaction with body image was found to overlap with the association between T and both depression and suicidality, and amygdala-prefrontal co-activation moderated the role of T on anxiety.

Childhood adversities are common among trans people and associated with adult depression and suicidality

Trans people suffer from increased rates of depression and suicidality even after gender-affirming medical interventions. The present study aims to examine the prevalence of childhood adversities in patients with gender dysphoria and to analyze its impact on adult depression and suicidality. Participants meeting diagnostic criteria of Gender Dysphoria were recruited in a cross-sectional multicenter study at four German health-care centers. Childhood adversities were assessed with the Childhood Trauma Questionnaire (CTQ) and additional single items for other childhood adversities. Associations between childhood adversities and adult depression and suicidality were calculated using regression analyses. A large majority of participants reported childhood adversities, and only 7% endorsed no adversities in the CTQ. Over 30% reported severe to extreme childhood adversities. One-fourth reported parents exhibiting violent behavior while bullying by peers was experienced by 70%. These adversities were associated with an increased risk for adult depression and suicidality. Time since beginning of hormonal therapy did not show a significant influence neither on depression nor on suicidality. Childhood adversities are common and associated with adult depression and suicidality in trans people. Adequately addressing these childhood adversities and providing trauma-informed mental health care might ameliorate the mental health burden in trans people.

11-oxygenated androgens and their relation to hypothalamus-pituitary-gonadal-axis disturbances in adults with congenital adrenal hyperplasia

CONTEXT

Hypothalamus-pituitary-gonadal (HPG)-axis disturbances are a common phenomenon in patients with classic congenital adrenal hyperplasia (CAH). 11-oxygenated androgens have been suggested to play a role in this context.

DESIGN

Cross-sectional single center study including 89 patients (N = 42 men, N = 55 women) with classic CAH.

MAIN OUTCOME MEASURES

Differences in steroid markers in men with hypogonadism and women with secondary amenorrhea with a special focus on 11-ketotestosterone (11KT) and 11β-hydroxyandrostenedione (11OHA4).

RESULTS

Hypogonadotropic hypogonadism was present in 23 % of men and 61 % of those women currently not on contraceptives suffered from irregular menstrual cycles or amenorrhea. Testicular adrenal rest tumor (TART) was documented in 28 % of men. 11KT (3.5x) and 11OHA4 (5.7x) among other adrenal steroids were significantly elevated in men with hypogonadism and in women with amenorrhea in comparison to those with a regular cycle (11KT: 5.2x; 11OHA4: 3.7x). 11-oxygenated androgens were not higher in men with TART than in those without. There was a negative association of 11KT and 11OHA4 with FSH but not with LH in men. As expected, all steroids were strongly correlated with each other and cases of disproportionally elevated 11-oxygenated androgens that could explain for HPG-disturbances or TART in otherwise controlled patients were rare and also found in eugonadal individuals.

CONCLUSIONS

In CAH, 11-oxygenated androgens are elevated in women with menstrual disturbances and in men with hypogonadotropic hypogonadism. Due to the close correlation of 11-oxygenated androgens with other adrenal steroids it remains to be shown if their measurement is superior to conventional markers of androgen control.

Menstrual variation in the acute testosterone and cortisol response to laboratory stressors correlate with baseline testosterone fluctuations at a within- and between-person level

Studies have compared HPA and HPG stress reactivity across the follicular and luteal phases to assess the menstrual impact of estradiol and progesterone fluctuations. Ovulatory shifts in baseline and stressor-induced testosterone among athletic women offer a new framework to explore these responses. Here we investigated menstrual variation in baseline testosterone as a predictor of the acute testosterone and cortisol response to laboratory stressors in female athletes. Using a semi-randomized crossover design, thirty athletic women completed a physical (4 × 6-s bike sprints) and psychological (5 × 2-min cognitive tests with social evaluation) stressor on day seven (D7), 14 (D14), and 21 (D21) of a menstrual cycle. Baseline fluctuations and acute changes in salivary testosterone and cortisol were measured. The D14 testosterone response to both stressors (13.7%) exceeded D7 (7.3%) and D21 (7.0%), whereas cortisol was less responsive on D14 (9.8%) than D7 (13.0%) and D21 (12.0%); all moderate to large effect size differences (p < 0.01). Baseline testosterone, which presented large individual and menstrual variation with a D14 peak, was significantly related (moderate correlations) to testosterone and cortisol stress reactivity on a between-person level. Both outcomes were related (weak correlations) to within-person fluctuations in baseline testosterone, but these effects were mediated by testing day. In conclusion, menstrual variation in baseline testosterone concentration correlated with testosterone and cortisol reactivity to a physical and psychological stressor. Thus, gradients of stressor-induced hormonal change showed some dependency to endogenous testosterone, both individual differences and fluctuations over time, among naturally cycling athletic women.Lay summaryThe female menstrual cycle is accompanied by dramatic shifts in estradiol and progesterone concentration, but less is known about testosterone variability and its role in stress regulation. In this study, menstrual fluctuations in baseline testosterone concentration correlated with acute testosterone and cortisol reactivity to laboratory stressors.

Sex and Gender Differences in Clinical Pharmacology: Implications for Transgender Medicine

The transgender adult population is growing globally, but clinical pharmacology has lagged behind other areas of transgender medicine. Medical care for transgender adults may include long‐term testosterone or estrogen treatment to align secondary sex characteristics with gender identity. Clinicians often use drug–drug interaction data from the general adult population to predict medication disposition or safety among transgender adults. However, this approach does not address the complex pharmacodynamic effects of hormone therapy in transgender adults. In this review, we critically examine sex‐related and gender‐related differences in clinical pharmacology and apply these data to discuss current gaps in transgender medicine.

Sex and Gender Differences in Clinical Pharmacology: Implications for Transgender Medicine

The transgender adult population is growing globally, but clinical pharmacology has lagged behind other areas of transgender medicine. Medical care for transgender adults may include long-term testosterone or estrogen treatment to align secondary sex characteristics with gender identity. Clinicians often use drug-drug interaction data from the general adult population to predict medication disposition or safety among transgender adults. However, this approach does not address the complex pharmacodynamic effects of hormone therapy in transgender adults. In this review, we critically examine sex-related and gender-related differences in clinical pharmacology and apply these data to discuss current gaps in transgender medicine.

Body Image and Sexual Desire in the Context of Gender Affirming Therapy: Results of a Cross-sectional Multi-centered Transgender Study

It has been posited that gender-affirming treatment (GAT) can have an influence on body image and sexual desire in trans people. This study aims to examine associations between GAT and sexual desire as well as whether body image mediates the influences of gender-affirming hormone therapy (GAHT) or gender-affirming surgery (GAS) on sexual desire. A total of 210 individuals diagnosed with gender dysphoria (n = 105 of each gender) were assessed via self-assessment questionnaires in a cross-sectional study. Associations between GAT and sexual desire were investigated via multivariate analyses of variance. Mediation analyses were conducted to clarify associations between GAHT/GAS, body image, and sexual desire. GAHT was associated with increased sexual desire only in transmen. GAS had no significant effect on sexual desire in transmen and transwomen. Body image did not mediate the influence of GAHT or GAS on sexual desire in both groups. GAHT and GAS had significant direct effects on body image in both genders, whereas body image showed no significant direct effect on sexual desire. The results indicate that effects of GAT on sexual desire seem to be attributable to other factors than body image, such as the hormonal influence of testosterone in transmen.

Testosterone, cortisol, and secretory immunoglobulin-A within a single day and across two sequential days among trans- and cis-gender men

BACKGROUND

Previous research on the association between testosterone (T) and immunity has produced conflicting results.

OBJECTIVES

We address two potential reasons for these empirical inconsistencies in the present research. First, the association between T and immunity may depend on which branch of the immune system is considered. Here, we examine secretory IgA (sIgA), a measure of mucosal immunity functionally related to respiratory infection risk. Second, the association between T and immunity may depend on a third regulatory variable. Therefore, we examine the interaction between T and cortisol (CORT) as well as their independent and combined effects on mucosal immunity. To do this, we explore intra-individual associations between sIgA, CORT, and T within a single day (i.e., morning vs. evening) and across 2 sequential mornings. We target two samples of men: (1) cisgender (i.e., born and identifying as men), and (2) transgender (i.e., born female but identifying as men) undergoing T therapy for gender realignment.

MATERIALS AND METHODS

One hundred and forty-eight adult men (transgender n = 29) provided saliva samples at three time points: (1) upon waking, (2) before sleep on the same day, and (3) upon waking the following day. Samples were assayed in duplicate for sIgA, T and CORT.

RESULTS

For cisgender men, sIgA, T, and CORT exhibited clear circadian rhythms and were significantly related within and between samples. For transgender men, evidence for circadian change was found for sIgA and CORT, but not T. Further, sIgA was associated with CORT, but not T.

DISCUSSION AND CONCLUSIONS

This study provides the first evidence that salivary T and sIgA concentrations are associated within a single day and across sequential days for cisgender men. Differences between cis- and transgender men suggest that this may only be true for T levels driven by endogenous production; however, future studies should employ a larger sample size.

Pituitary Hyperplasia, Hormonal Changes and Prolactinoma Development in Males Exposed to Estrogens-An Insight From Translational Studies

Estrogen signaling plays an important role in pituitary development and function. In sensitive rat or mice strains of both sexes, estrogen treatments promote lactotropic cell proliferation and induce the formation of pituitary adenomas (dominantly prolactin or growth-hormone-secreting ones). In male patients receiving estrogen, treatment does not necessarily result in pituitary hyperplasia, hyperprolactinemia or adenoma development. In this review, we comprehensively analyze the mechanisms of estrogen action upon their application in male animal models comparing it with available data in human subjects. Sex-specific molecular targets of estrogen action in lactotropic (PRL) cells are highlighted in the context of their proliferative and secretory activity. In addition, putative effects of estradiol on the cellular/tumor microenvironment and the contribution of postnatal pituitary progenitor/stem cells and transdifferentiation processes to prolactinoma development have been analyzed. Finally, estrogen-induced morphological and hormone-secreting changes in pituitary thyrotropic (TSH) and adrenocorticotropic (ACTH) cells are discussed, as well as the putative role of the thyroid and/or glucocorticoid hormones in prolactinoma development, based on the current scarce literature.

Sex differences in stress-related disorders: Major depressive disorder, bipolar disorder, and posttraumatic stress disorder

Stress-related disorders, such as mood disorders and posttraumatic stress disorder (PTSD), are more common in women than in men. This sex difference is at least partly due to the organizing effect of sex steroids during intrauterine development, while activating or inhibiting effects of circulating sex hormones in the postnatal period and adulthood also play a role. Such effects result in structural and functional changes in neuronal networks, neurotransmitters, and neuropeptides, which make the arousal- and stress-related brain systems more vulnerable to environmental stressful events in women. Certain brainstem nuclei, the amygdala, habenula, prefrontal cortex, and hypothalamus are important hubs in the stress-related neuronal network. Various hypothalamic nuclei play a central role in this sexually dimorphic network. This concerns not only the hypothalamus-pituitary-adrenal axis (HPA-axis), which integrates the neuro-endocrine-immune responses to stress, but also other hypothalamic nuclei and systems that play a key role in the symptoms of mood disorders, such as disordered day-night rhythm, lack of reward feelings, disturbed eating and sex, and disturbed cognitive functions. The present chapter focuses on the structural and functional sex differences that are present in the stress-related brain systems in mood disorders and PTSD, placing the HPA-axis in the center. The individual differences in the vulnerability of the discussed systems, caused by genetic and epigenetic developmental factors warrant further research to develop tailor-made therapeutic strategies.

Vasopressin Surrogate Marker Copeptin as a Potential Novel Endocrine Biomarker for Antidepressant Treatment Response in Major Depression: A Pilot Study

BACKGROUND

Major depressive disorder (MDD) constitutes the leading cause of disability worldwide. Although efficacious antidepressant pharmacotherapies exist for MDD, only about 40-60% of the patients respond to initial treatment. However, there is still a lack of robustly established and applicable biomarkers for antidepressant response in everyday clinical practice.

OBJECTIVE

This study targets the assessment of the vasopressin (AVP) surrogate marker Copeptin (CoP), as a potential peripheral hypothalamic-level biomarker of antidepressant treatment response in MDD.

METHODS

We measured baseline and dynamic levels of plasma CoP along with plasma ACTH and cortisol (CORT) in drug-naive outpatients with MDD before and after overnight manipulation of the hypothalamic-pituitary-adrenal (HPA) axis [i.e., stimulation (metyrapone) and suppression (dexamethasone)] on three consecutive days and their association with treatment response to 4 weeks of escitalopram treatment.

RESULTS

Our findings suggest significantly higher baseline and post-metyrapone plasma CoP levels in future non-responders, a statistically significant invert association between baseline CoP levels and probability of treatment response and a potential baseline plasma CoP cut-off level of above 2.9 pmol/L for future non-response screening. Baseline and dynamic plasma ACTH and CORT levels showed no association with treatment response.

CONCLUSIONS

This pilot study provide first evidence in humans that CoP may represent a novel, clinically easily applicable, endocrine biomarker of antidepressant response, based on a single-measurement, cut-off level. These findings, underline the role of the vasopressinergic system in the pathophysiology of MDD and may represent a significant new tool in the clinical and biological phenotyping of MDD enhancing individual-tailored therapies.