Functional hypothalamic and drug-induced amenorrhea: an overview

Psychological stressors involved in the pathogenesis of premature ovarian insufficiency and potential intervention measures

Premature ovarian insufficiency (POI) is a common gynecological endocrine disease, which seriously affects women's physical and mental health and fertility, and its incidence is increasing year by year. With the development of social economy and technology, psychological stressors such as anxiety and depression caused by social, life and environmental factors may be one of the risk factors for POI. We used PubMed to search peer-reviewed original English manuscripts published over the last 10 years to identify established and experimental studies on the relationship between various types of stress and decreased ovarian function. Oxidative stress, follicular atresia, and excessive activation of oocytes, caused by Stress-associated factors may be the main causes of ovarian function damage. This article reviews the relationship between psychological stressors and hypoovarian function and the possible early intervention measures in order to provide new ideas for future clinical treatment and intervention.

Dose-response association between 24-hour total movement activity and testosterone deficiency in adult males

Background and objectives

Previous studies on the relationship between physical activity and testosterone are limited and controversial. Hence we investigated whether high level of physical activity is associated with a low risk of testosterone deficiency (TD).

Methods

This cross-sectional analysis was conducted in a representative sample of US adult males who participated in the 2011-2014 cycle of the National Health and Nutrition Examination Survey (NHANES). We used the monitor independent movement summary (MIMS) to assess activity intensity, a novel physical activity metrics developed using raw data collected by accelerometers. Multivariable regression and smooth curve fitting was used to describe the relationships between physical activity and TD, and segmented regression model were used to analyze the threshold effect between them. Sensitivity analysis was conducted using interaction and stratified analysis.

Results

A U-shaped relationship between daily MIMS units and risk of TD was observed. The optimal value of daily MIMS units for the lowest risk of TD was 14.77 (×103), the risk of TD decreased by 5% in patients per unit increase of daily MIMS units when daily MIMS units <14.77 (×103) (adjusted OR = 0.95, 95%CI: 0.91, 0.99), but increased by 12% per unit increase of daily MIMS units when daily MIMS units ≥14.77 (×103) (adjusted OR = 1.12, 95%CI: 1.01, 1.23). In sensitivity analyses, the threshold effect was also similar according to baseline characteristics (P-interaction >0.05).

Conclusion

In a nationally representative sample of US adult males, light to moderate intensity physical activity is associated with a lower odds of TD, while high-intensity physical activity is associated with a higher risk of TD.

Neuroendocrine disturbances in women with functional hypothalamic amenorrhea: an update and future directions

Functional hypothalamic amenorrhea (FHA) is one of the most common causes of both primary and secondary amenorrhea in women of reproductive age. It is characterized by chronic anovulation and the absence of menses that appear as a result of stressors such as eating disorders, excessive exercise, or psychological distress. FHA is presumed to be a functional disruption in the pulsatile secretion of hypothalamic gonadotropin-releasing hormone, which in turn impairs the release of gonadotropin. Hypoestrogenism is observed due to the absence of ovarian follicle recruitment. Numerous neurotransmitters have been identified which play an important role in the regulation of the hypothalamic-pituitary-ovarian axis and of which the impairment would contribute to developing FHA. In this review we summarize the most recent advances in the identification of contributing neuroendocrine disturbances and relevant contributors to the development of FHA.

Current pharmacotherapy and future directions for neuroendocrine causes of female infertility

INTRODUCTION

Infertility is recognized as a major global health issue, often associated with significant psychological distress for affected couples. Causes of female infertility include endocrine conditions leading to oligo/anovulation, in addition to structural causes such as tubal, uterine, or peritoneal disorders. Pharmacological treatments, targeting pathways in the hypothalamic-pituitary-ovarian axis, can improve rates of ovulation, conception, pregnancy, and birth. Some existing therapeutic options are hindered by limited efficacy or by a non-physiological mechanism, which can risk excessive stimulation and treatment-related adverse effects. Therefore, there is a continued need for novel therapies to improve care for patients suffering with infertility.

AREAS COVERED

In this review, the authors focus on endocrine causes of oligo/anovulation in women and on advances in assisted reproductive technology. Current pharmacological treatments and putative future therapeutic avenues in development to aid fertility in women are outlined.

EXPERT OPINION

A deeper understanding of the reproductive neuroendocrine network governing hypothalamic gonadotropin-releasing hormone release can offer novel therapeutic targets for the treatment of female subfertility, leading to improved clinical outcomes, less invasive routes of administration, and decreased treatment-related side-effects. The ultimate aim of development in female subfertility is to offer therapeutic interventions that are effective, reproducible, associated with minimal risks, and have an acceptable route of administration.

Stress, kisspeptin, and functional hypothalamic amenorrhea

Functional hypothalamic amenorrhea (FHA) is the most common cause of secondary amenorrhea in women of reproductive age. FHA is predominantly caused by stress, decreased caloric intake, excessive exercise, or a combination thereof. These physical, psychological, and metabolic stressors cause aberration in the pulsatile release of gonadotropin-releasing hormone (GnRH) and subsequently impair function of the hypothalamic-pituitary-ovarian (HPO) axis. Various neurotransmitters acting in the central nervous system are involved in control of the HPO axis and of these, kisspeptin is one of the most important. Corticotropin-releasing hormone (CRH), also inhibits the pulsatile secretion of GnRH and also acts as an intermediary between stress factors and the reproductive system. One of the main ongoing concerns in patients with FHA is chronic hypoestrogenism, a condition, which is associated with sexual dysfunction and infertility. It may also lead to osteoporosis, and predispose to neurodegenerative and cardiovascular diseases. Treatment of FHA requires the elimination of causative factors, however, making the necessary lifestyle changes is not always easy to initiate and maintain. Broadening our knowledge of the complex neural mechanisms regulating reproductive function in which kisspeptin plays a key role can help in the development of new treatment options such as the potential of kisspeptin receptor agonists for patients with FHA.

The influence of estro-progestin therapy on neurohormonal activity in functional hypothalamic amenorrhea

Background: Functional hypothalamic amenorrhea (FHA) is a chronic endocrine disorder caused by the abnormal pulsatile secretion of neurohormones in the hypothalamus. Secretion of GnRH is regulated by kisspeptin/neurokinin B/dynorphin (KNDy) neurons. These neurons produce, among other neurohormones, neurokinin B (NKB) which regulates the coordinated stimulation or inhibition of GnRH secreting neurons. Aim of the study: Assessment and comparison of serum NKB in patients with FHA at baseline, and following 6 months of estrogen-progestagen therapy. Materials and methods: Fifty-five patients with functional hypothalamic amenorrhea were included in the study group. Serum concentrations of neurokinin B (NKB), follicle stimulating hormone (FSH), luteinizing hormone (LH), 17-β-estradiol (E2), prolactin (PRL), cortisol, testosterone (T), dehydroepiandrosterone sulfate (DHEA-S), thyroid-stimulating hormone (TSH), free thyroxine (fT4), fasting glucose and insulin, as well as lipid profile were measured at baseline. At the time of diagnosis, patients with FHA were prescribed a course of 2 mg 17-β-estradiol and 10 mg dydrogesterone for duration of 6 months. Serum NKB was then reassessed following treatment at 6 months. Results: At baseline, the FHA group was found to have a decreased serum NKB concentration when compared to a healthy control group. Following 6 months of sequential estrogen-progestogen hormone therapy, this study did not find any statistically significant difference in serum NKB concentration in the treatment arm compared to baseline. Conclusions: For the first time, NKB secretion has been studied in patients with FHA. A significantly lower level of serum NKB was observed in these patients at baseline, when compared to a control group. After 6 months of combination estrogen-progesterone therapy, no significant changes in NKB levels were observed in these patients. These findings, for the first time in the literature, provide insight into the perceived benefit of HRT, calling into question its benefit in addressing the underlying etiopathogenetic contributors of FHA. These new findings may contribute to more targeted and appropriate treatment of such patients in the future.

Cognition, Behavior, Sexuality, and Autonomic Responses of Women with Hypothalamic Amenorrhea

(1) Background: Functional Hypothalamic Amenorrhea (FHA) can be caused by the hyper activation of neuro-endocrine responses to stress. Among other endocrine factors and hypothalamic dysfunctions, the psychophysiological stress response can very frequently lead to an inhibition of the gonadal-pituitary axis. The aim of this study was to investigate the level of neurovegetative activation in a group of young women affected by this condition. (2) Methods: Twenty-five women (mean age = 21.1 ± 4.34) with FHA were consecutively recruited. Information on psycho-physiological distress was collected through a Psychopathological assessment (with the administration of three psychometric tests) and the Psychophysiological Stress Profile (PSP). Their data were compared with a control group. (3) Results: In the PSP, the patients displayed significantly higher values compared to controls in terms of the parameters of muscle tension (sEMG), skin conductance (SCL/SCR), heart rate (HR), and peripheral temperature (PT). Furthermore, autonomic hyper-activation at rest, marked reactivity to stress, and reduced recovery were seen. Moreover, a condition characterized by psychological distress (anxiety and somatic complaints, depressed and irritable mood, obsessive-compulsive traits) emerged. (4) Conclusions: The results highlight autonomic hyper-activation in FHA, which is also associated with psychological distress. Considering that FHA is a condition that affects multiple systems between mind and body, a multimodal, multidimensional, and multidisciplinary assessment of stress is becoming an emerging need.

Bone health in adolescence

Adolescence is a fundamental period for the formation of the skeleton, because is the stage in which bones grow more in both size and strength, laying a solid foundation for the future health of the skeleton. Any condition interfering with optimal peak bone mass accrual can increase fracture risk later in life. Up to 80% of peak bone mass is genetically determined while the remaining 20% is modulated by environmental factors that, if deleterious, may result in low bone mineral density (BMD) and an increased risk of fracture. The preferred test to assess bone health is dual-energy x-ray absorptiometry (spine or total body less head) using Z scores instead of T scores, even though in short stature or growth delay, should be used the height Z-score. The correction of risk factors is the first treatment for low BMD in children and adolescents. It's necessary having a correct lifestyle for preserving bone health: a proper nutrition, an adequate physical weight-bearing activity and avoidance of alcohol intake and tobacco smoke. Bisphosphonates could be used in children who sustained osteoporotic fractures, impairing quality of life, when spontaneous recovery is low for the persistence of osteoporosis risk factors. This clinical review discusses factors affecting bone health during childhood and adolescence and deals with diagnosis and treatment of low bone mass or osteoporosis in this age group.

Has Menstruation Disappeared? Functional Hypothalamic Amenorrhea-What Is This Story about?

Functional hypothalamic amenorrhea (FHA) is a very common condition affecting women of procreative age. There are many reasons for this disorder, including a low availability of energy in the diet, low micro- and macronutrient intake, overly intensive physical activity, disturbed regeneration processes, sleep disorders, stress, and psychological disorders. The main determinant is long-term stress and an inability to handle the effects of that stress. FHA is a very complex disorder and often goes undiagnosed. Moreover, therapeutic interventions do not address all the causes of the disorder, which could have implications for women’s health. As shown by scientific reports, this condition can be reversed by modifying its causes. This review of the literature aims to update the current knowledge of functional hypothalamic amenorrhea and underscores the complexity of the disorder, with particular emphasis on the nutritional aspects and potential interventions for restoring balance.

Mechanisms of Central Hypogonadism

Reproductive function depends upon an operational hypothalamo–pituitary–gonadal (HPG) axis. Due to its role in determining survival versus reproductive strategies, the HPG axis is vulnerable to a diverse plethora of signals that ultimately manifest with Central Hypogonadism (CH) in all its many guises. Acquired CH can result from any pituitary or hypothalamic lesion, including its treatment (such as surgical resection and/or radiotherapy). The HPG axis is particularly sensitive to the suppressive effects of hyperprolactinaemia that can occur for many reasons, including prolactinomas, and as a side effect of certain drug therapies. Physiologically, prolactin (combined with the suppressive effects of autonomic neural signals from suckling) plays a key role in suppressing the gonadal axis and establishing temporary CH during lactation. Leptin is a further key endocrine regulator of the HPG axis. During starvation, hypoleptinaemia (from diminished fat stores) results in activation of hypothalamic agouti-related peptide neurons that have a dual purpose to enhance appetite (important for survival) and concomitantly suppresses GnRH neurons via effects on neural kisspeptin release. Obesity is associated with hyperleptinaemia and leptin resistance that may also suppress the HPG axis. The suppressibility of the HPG axis also leaves it vulnerable to the effects of external signals that include morphine, anabolic-androgenic steroids, physical trauma and stress, all of which are relatively common causes of CH. Finally, the HPG axis is susceptible to congenital malformations, with reports of mutations within >50 genes that manifest with congenital CH, including Kallmann Syndrome associated with hyposmia or anosmia (reduction or loss of the sense of smell due to the closely associated migration of GnRH with olfactory neurons during embryogenesis). Analogous to the HPG axis itself, patients with CH are often vulnerable, and their clinical management requires both sensitivity and empathy.

Perils of prolonged ovarian suppression and hypoestrogenism in the treatment of breast cancer: Is the risk of treatment worse than the risk of recurrence?

Premenopausal breast cancer is usually estrogen receptor positive, and hence, prolonged ovarian suppression by medical or surgical means to prevent recurrence has become standard of management to improve disease-free survival. Ten-year adjuvant tamoxifen therapy is associated with 3.5% fewer recurrences compared to five years. The SOFT trial demonstrated small but statistically significant incremental improvements in long-term disease-free survival by the addition of gonadotropin-releasing hormone analog treatment (triptorelin) to an aromatase inhibitor (exemestane). Profound hypoestrogenism in the premenopausal age group may not be well tolerated due to a host of bothersome side effects (primarily vasomotor symptoms, musculoskeletal complaints, genitourinary syndrome of menopause, and mood disorders). Prolonged hypoestrogenism in younger women is associated with premature development of cardiovascular disease, bone loss, cognitive decline, and all-cause mortality. This paper explores multi-system consequences of prolonged hypoestrogenism in premenopausal women derived from studies of women with and without breast cancer. Pretreatment counseling in estrogen receptor positive breast cancer should emphasize the benefit of prolonged estrogen suppression on breast cancer recurrence and established risks of lifelong hypoestrogenism on quality of life and all-cause mortality. Future genomic research may help identify the best candidates for extended ovarian suppression to avoid treating many women when only a minority benefit.

Effects of Environment and Lifestyle Factors on Anovulatory Disorder

Anovulatory disorder comprises around 30% of female infertility. The origin of ovulatory failure is rooted in pituitary FSH secretion. Any factor or process that disrupts the finely tuned interactions of hypothalamo-pituitary-ovarian axis can potentially lead to anovulation. The World Health Organization (WHO) has classified anovulatory disorders into three categories: hypothalamic-pituitary failure, hypothalamic-pituitary dysregulation, and ovarian failure. Due to industrial development, environmental pollution, and global warming, the human living environment has undergone tremendous changes. Industrial waste, noise, pesticides, fertilizers, and vehicular emission are visible pollutants responsible for environmental contamination and ill effects on health of all living systems. A considerable body of research suggests that chemical exposures in the environment or workplace may be associated with endocrine disruption of the synthesis, secretion, transport, binding, or elimination of natural hormones. For instance, some advanced biological mechanisms suggest that heavy metals may affect progesterone production, which possibly disturbs endocrine function in pregnant women. On the other hand, our lifestyle factors have also changed accordingly, which greatly influence overall health and well-being, including fertility. Many lifestyle factors such as nutrition, weight, exercise, and psychological stress can have substantial effects on female ovulation.

Endogenous transient doping: physical exercise acutely increases testosterone levels-results from a meta-analysis

PURPOSE

Although endogenous testosterone levels are demonstrated to be affected by both acute exercise and resistance training, the dynamic regulation of androgen production after physical activity is still a matter of debate. This meta-analysis was designed to assess whether physical exercise acutely affects testosterone levels in men.

METHODS

The literature search was conducted to identify longitudinal trials evaluating the acute change of both total testosterone (TT) and free testosterone (fT) after physical activity in adult men. Sensitivity analyses were performed considering the sample collected (blood or saliva), the intensity of the physical exercise and the interval between the end of the exercise and the sample collection.

RESULTS

Forty-eight studies were included in the analysis, accounting for 126 trials. A total of 569 patients were enrolled (mean age 29.7 ± 13.1 years). The physical activity increased acutely TT (standardized mean difference 0.74, 95%CI: 0.56, 0.91 nmol/L), considering both serum and saliva samples (p < 0.001). Testosterone increased after moderate (p < 0.001) and high-intensity (p < 0.001) exercises, but not after mild physical activity (p = 0.19). Moreover, the testosterone increase was evident when measured immediately at the end of the exercise and within 30 min (p < 0.001), but not after 30 min (p = 0.930). Similar significant results were obtained considering fT, while SHBG did not change after physical activity (p = 0.090).

CONCLUSION

The comprehensive evaluation of the acute physical activity effect on testosterone levels identified a clear increase after exercise, irrespective of the sample collected. The main determinant of this fluctuation was the exercise intensity, with a mechanism that seems to be mostly SHBG independent. In particular, moderate/intense physical activity resulted able to increase endogenous androgenic production, albeit acutely and transitory.

TRIAL REGISTRATION NUMBER

PROSPERO registration ID: 157348.

The effect of underweight on female and male reproduction

Chronic energy deficiency can impair the hypothalamic-pituitary-gonadal (HPG) axis and lead to hypothalamic anovulation in underweight women. This review presents the syndromes related to underweight status that are associated with infertility, summarizes the underlying mechanisms, and reviews the available treatment options. Eating disorders, such as anorexia nervosa (AN), constitute the most common cause of infertility in underweight women, who, in addition, experience miscarriages, and sexual dysfunction. The relative energy deficiency in sports (RED-S; former terminology: athlete's triad) involves menstrual dysfunction due to low energy availability, which results in anovulation. Moreover, lipodystrophies, malnutrition, starvation, systematic illnesses (malignancies, endocrinopathies, infectious diseases, advanced chronic diseases, neurologic illnesses), and the utilization of drugs can cause excessive weight loss. They may result in fertility problems due to the loss of adipose tissue and the subsequent hormonal disturbances. Each of these conditions requires multidisciplinary management. Nutritional counseling should target the restoration of energy balance by increasing intake and reducing output. Medical treatment, recommended only for patients who did not respond to standard treatment, may include antipsychotics, antidepressants, or leptin administration. Finally, psychiatric treatment is considered an integral part of the standard treatment.