Sex Differences in Effects of Obesity on Reproductive Hormones and Glucose Metabolism in Early Puberty

Longitudinal analysis of cortisol changes during pubertal development in indigenous Qom girls

Pubertal research has primarily focused on hypothalamic-pituitary-gonadal axis (HPG) regulation of puberty, though the hypothalamic-pituitary-adrenal axis (HPA) is increasingly considered critical. Heightened HPA function proxied by increasing cortisol levels may play a role in accelerated pubertal timing. However, the extent to which cortisol varies across ages and its relation to pubertal changes in linear growth are less well substantiated. We explored relationships between age, linear growth, adiposity, C-peptide (proxy for insulin), and cortisol across puberty, and we tested whether higher cortisol levels are associated with earlier ages at menarche and peak height velocity. We utilize longitudinal data (n = 777 urine samples) from Qom females ages 7-14 (n = 46) and test our pre-registered analysis using Bayesian longitudinal mixed effects models and joint modeling techniques. We find limited evidence supporting the overarching hypothesis that HPA upregulation is associated with pubertal maturation or timing. We find some evidence that HPA upregulation, as proxied by cortisol, may be more clearly related to differences in relative linear growth at early-mid puberty, as measured by height-for-age z-scores. Transdisciplinary perspectives on puberty, including the assumption that stressors acting via cortisol accelerate pubertal development, are discussed.

Comprehensive transition of care for polycystic ovary syndrome from adolescence to adulthood

Polycystic ovary syndrome (PCOS) is a lifelong chronic condition that affects one in ten females and can be diagnosed in adolescence. As adolescents with PCOS transition to adulthood, counselling for lifestyle management and mental health concerns often transition from involving the family unit to increasingly individual-focused approaches. PCOS is associated with a large range of comorbidities affecting reproductive, metabolic, dermatological, and psychological health. The diagnosis and comorbidities of PCOS are influenced by pubertal hormones and need to be reassessed continuously to ensure that treatment remains appropriate for age and development. As young patients grow up, personal concerns often change, especially in relation to reproductive management. In this Review, we present prevalence rates, screening tools, and treatment recommendations for PCOS-related conditions, and we consider the diagnostic and clinical elements of optimal transition of care models that ensure continuity of comprehensive care for adolescents moving from the paediatric health-care system to the adult health-care system.

Association between serum vitamin A and body mass index in adolescents from NHANES 1999 to 2006

Vitamin A plays a pivotal role in health, particularly in regulating fat metabolism. Despite its significance, research into the direct relationship between vitamin A levels and obesity, especially among adolescents, is sparse. This study aims to explore this association within the adolescent population in the United States. This cross-sectional study analyzed the National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2006, with 8218 participants. The levels of vitamin A in the serum were determined based on utilizing high-performance liquid chromatography with photodiode array detection. The relationship between serum vitamin A concentrations and body mass index (BMI) was evaluated using weighted multiple linear regression models, incorporating subgroup analyses by sex and race/ethnicity to provide nuanced insights. A positive correlation was observed between serum vitamin A levels and BMI, with BMI increasing progressively across vitamin A quartiles (P < 0.001). Using the lowest quartile of serum vitamin A as a reference, the BMI of the highest quartile of serum vitamin A was 1.236 times higher (95% CI 0.888, 1.585). Subgroup analyses revealed that this positive association persisted across different genders and racial/ethnic groups (P < 0.001). Notably, smooth curve fitting and saturation threshold analysis unveiled an inverted U-shaped relationship between serum vitamin A and BMI among female adolescents, non-Hispanic Whites, Mexican Americans, and other races/ethnicities groups. Our study substantiates the association between serum vitamin A levels and the risk of obesity/overweight status in adolescents. The findings suggest the potential serum vitamin A is an early biomarker for identifying obesity risk, although further studies are needed to determine to clarify its role as a contributing factor to obesity. This study contributes to the understanding of nutritional influences on adolescent obesity, highlighting the need for targeted interventions based on serum biomarkers.

Causal associations of cognition, intelligence, education, health and lifestyle factors with cervical spondylosis: a mendelian randomization study

Background: Education, cognition, and intelligence are phenotypically and genetically related. Education has been shown to have a protective effect on the risk of developing cervical spondylosis. However, it is unclear whether cognition and intelligence have independent causal effects on cervical spondylosis, and whether health and lifestyle factors influence this association. Methods: We first assessed the independent effects of education, cognition, and intelligence on cervical spondylosis by two-sample Mendelian randomization and multivariable Mendelian randomization analysis, and evaluated 26 potential association mediators using two-step Mendelian randomization, and calculated the median proportion. Results: The results showed that only education had an independent causal effect on cervical spondylosis, and had a protective effect on the risk of cervical spondylosis (β: 0.3395; se: 0.166; p < 0.05; OR:0.71; [95%CI: 0.481-0.943]. Of the 26 potential associated mediators, a factor was identified: SHBG (mediated proportion: 2.5%). Univariable Mendelian randomization results showed that the risk factors for cervical spondylosis were time spent watching TV (OR:1.96; [95%CI: 1.39-2.76]), smoking (OR:2.56; [95%CI: 1.061-1.486]), body mass index (OR:1.26; [95%CI: 1.124-1.418]), percentage of body fat (OR:1.32; [95%CI: 1.097-1.593]), major depression (OR:1.27; [95%CI: 1.017-1.587]) and sitting height (OR:1.15; [95%CI: 1.025-1.291]). Protective factors include computer using (OR:0.65; [95%CI: 0.418-0.995]), sex hormone binding globulin (OR:0.87; [95%CI: 0.7955-0.951]) and high-density lipoprotein (OR:0.90; [95%CI: 0.826-0.990]). Conclusion: Our findings demonstrate the causal and independent effects of education on cervical spondylosis and suggest that lifestyle media may be a priority target for the prevention of cervical spondylosis due to low educational attainment.

High Fat Diet and Polycystic Ovary Syndrome (PCOS) in Adolescence: An Overview of Nutritional Strategies

Polycystic ovary syndrome (PCOS) is a multifaceted and heterogeneous disorder, linked with notable reproductive, metabolic, and psychological outcomes. During adolescence, key components of PCOS treatment involve weight loss achieved through lifestyle and dietary interventions, subsequently pursued by pharmacological or surgical therapies. Nutritional interventions represent the first-line therapeutic approach in adolescents affected by PCOS, but different kinds of dietary protocols exist, so it is necessary to clarify the effectiveness and benefits of the most well-known nutritional approaches. We provided a comprehensive review of the current literature concerning PCOS definition, pathophysiology, and treatment options, highlighting nutritional strategies, particularly those related to high-fat diets. The high-fat nutritional protocols proposed in the literature, such as the ketogenic diet (KD), appear to provide benefits to patients with PCOS in terms of weight loss and control of metabolic parameters. Among the different types of KD studies, very low-calorie ketogenic diets (VLCKD), can be considered an effective dietary intervention for the short-term treatment of patients with PCOS. It rapidly leads to weight loss alongside improvements in body composition and metabolic profile. Even though extremely advantageous, long-term adherence to the KD is a limiting factor. Indeed, this dietary regimen could become unsustainable due to the important restrictions required for ketosis development. Thus, a combination of high-fat diets with more nutrient-rich nutritional regimens, such as the Mediterranean diet, can amplify positive effects for individuals with PCOS.

Prediction of body mass index and skeletal maturity for early menarche risk at menarche onset: a cross-sectional study of Chinese girls

BACKGROUND

This study aimed to assess the predictive value of body mass index (BMI) and skeletal maturity for the occurrence of early menarche in Chinese girls.

METHODS

A cross-sectional analysis was conducted on 785 girls aged 8.1-14.6 years who visited our hospital within 3 months of menarche onset. Early menarche was defined as menarche age (MA) <10 years. Skeletal maturity was classified based on the difference between bone age (BA) and chronological age (CA), termed BA-CA; advanced BA was defined as BA-CA>2 years.

RESULTS

The average MA was 10.7 (SD: 1.1) years, with a prevalence of early menarche of 23.3%. BA exhibited relative stability compared with MA, with an average of 12.8 (SD: 0.5) years at menarche onset. At menarche onset, the average height, weight and BMI were 149.1 (SD: 5.1) cm, 43.3 (SD: 7.2) kg and 19.4 (SD: 2.8) kg/m², respectively. Logistic regression analyses indicated that every 1-year increment in BA-CA was independently associated with a 18.90-fold higher risk of early menarche (95% CI 11.77 to 30.32), respectively, and remained statistically significant even after adjusting for height or mid-parental height. Furthermore, the prediction of BA-CA for early menarche demonstrated a dose-dependent pattern across BMI categories, with the greatest risk observed in normal-weight girls, the lowest risk in obese girls and an intermediate risk in overweight girls at the same degree of BA advancement.

CONCLUSIONS

Our findings provide evidence supporting the significant contributions of BMI and skeletal maturity in predicting early menarche among Chinese girls at menarche onset. Additionally, the results suggest a dose-dependent relationship between skeletal maturity and BMI categories, with normal-weight girls displaying a higher risk of early menarche compared to overweight and obese girls with the same degree of BA advancement.

Beyond the Metabolic Syndrome: Non-Obvious Complications of Obesity in Children

Obesity is currently one of the most significant public health challenges worldwide due to the continuous increase in obesity rates among children, especially younger children. Complications related to obesity, including serious ones, are increasingly being diagnosed in younger children. A search was performed from January 2023 to September 2023 using the PubMed, Cochrane Library, Science Direct, MEDLINE, and EBSCO databases. The focus was on English-language meta-analyses, systematic reviews, randomized clinical trials, and observational studies worldwide. Four main topics were defined as follows: disorders of glucose metabolism; liver disease associated with childhood obesity; the relationship between respiratory disorders and obesity in children; and the effects of obesity on the hypothalamic-pituitary-gonadal axis and puberty. Understanding potential complications and their underlying mechanisms can expedite the diagnostic process and enhance the effectiveness of treatment. We aspire that this study will bring insight into the often-overlooked complications associated with obesity.

Combined training in addition to cortisol reduction can improve the mental health of girls with precocious puberty and obesity

Background

Obesity and central precocious puberty (CPP) are associated with increased anxiety, depression, and anger in girls. The contribution of exercise as an efficacious component in decreasing anxiety, depression, and anger has been increasingly recognized.

Objectives

This study aims to evaluate the effects of combined training on cortisol, anxiety, depression, and anger in overweight and obese girls with CPP.

Methods

The study involved 30 girls aged 7-9 years diagnosed with CPP (undergoing triptorelin treatment) and dealing with obesity. In addition, these girls scored higher than the cut-off line for anxiety, depression, and anger. The participants were divided into two groups, with 15 individuals in each group. The exercise group engaged in 60 min of combined aerobic and resistance training three times per week for a duration of 12 weeks. On the other hand, the control group did not receive any training. Throughout the study, the serum cortisol levels were measured in both groups. Anxiety, anger, and depression questionnaires were also completed at three different stages, namely, baseline, 12 weeks, and 16 weeks (after a 4-week period of detraining).

Results

In the exercise group, there was a significant decrease (P < 0.05) in cortisol serum levels and anxiety, depression, and anger scores. These changes were observed consistently during detraining (P > 0.05). However, in the control group, only the depression score significantly decreased (P < 0.05).

Conclusions

Based on the results, it can be concluded that combined training is a method to improve the mental health of CPP girls.

Clinical Trial Registration

https://en.irct.ir/trial/61990, identifier IRCT20170411033378N10.

Endocrinological Involvement in Children and Adolescents Affected by COVID-19: A Narrative Review

Since the advent of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, an increased incidence of several endocrinological anomalies in acute-phase and/or long-term complications has been described. The aim of this review is to provide a broad overview of the available literature regarding changes in the worldwide epidemiology of endocrinological involvement in children since December 2019 and to report the evidence supporting its association with coronavirus disease 2019 (COVID-19). Although little is known regarding the involvement of endocrine organs during COVID-19 in children, the current evidence in adults and epidemiological studies on the pediatric population suggest the presence of a causal association between the virus and endocrinopathies. Untreated transient thyroid dysfunction, sick euthyroid syndrome, nonthyroidal illness syndrome, and hypothalamic-pituitary-adrenal (HPA) axis and central precocious puberty have been observed in children in acute infection and/or during multisystem inflammatory syndrome development. Furthermore, a higher frequency of ketoacidosis at onset in children with a new diagnosis of type 1 diabetes is reported in the literature. Although the direct association between COVID-19 and endocrinological involvement has not been confirmed yet, data on the development of different endocrinopathies in children, both during acute infection and as a result of its long-term complications, have been reported. This information is of primary importance to guide the management of patients with previous or current COVID-19.

Impact of puberty, sex determinants and chronic inflammation on cardiovascular risk in young people

Worrying trends of increased cardiovascular disease (CVD) risk in children, adolescents and young people in the Modern Era have channelled research and public health strategies to tackle this growing epidemic. However, there are still controversies related to the dynamic of the impact of sex, age and puberty on this risk and on cardiovascular health outcomes later in life. In this comprehensive review of current literature, we examine the relationship between puberty, sex determinants and various traditional CVD-risk factors, as well as subclinical atherosclerosis in young people in general population. In addition, we evaluate the role of chronic inflammation, sex hormone therapy and health-risk behaviours on augmenting traditional CVD-risk factors and health outcomes, ultimately aiming to determine whether tailored management strategies for this age group are justified.

Risk factors on testicular function in adolescents

PURPOSE

Adolescence represents an important window for gonadal development. The aim of this review is to carry out a critical excursus of the most recent literature on endogenous and exogenous risk factors related to testicular function, focusing the research on adolescence period.

METHODS

A comprehensive literature search within PubMed was performed to provide a summary of currently available evidence regarding the impact on adolescence of varicocele, cryptorchidism, cancer, diabetes, lifestyle factors, endocrine disruptors, obesity and sexually transmitted diseases. We focused on human studies that evaluated a possible impact of these factors on puberty timing and their effects on andrological health.

RESULTS

Evidence collected seems to suggest that andrological health in adolescence may be impaired by several factors, as varicocele, cryptorchidism, and childhood cancer. Despite an early diagnosis and treatment, many adolescents might still have symptoms and sign of a testicular dysfunction in their adult life and at the current time it is not possible to predict which of them will experience andrological problems. Lifestyle factors might have a role in these discrepancies. Most studies point out towards a correlation between obesity, insulin resistance, alcohol, smoking, use of illegal drugs and testicular function in pubertal boys. Also, endocrine disruptors and sexually transmitted diseases might contribute to impair reproductive health, but more studies in adolescents are needed.

CONCLUSION

According to currently available evidence, there is an emerging global adverse trend of high-risk and unhealthy behaviors in male adolescents. A significant proportion of young men with unsuspected and undiagnosed andrological disorders engage in behaviors that could impair testicular development and function, with an increased risk for later male infertility and/or hypogonadism during the adult life. Therefore, adolescence should be considered a key time for intervention and prevention of later andrological diseases.

Effects of a 3-Month Physical Training on Cortisol and Testosterone Responses in Women After Bariatric Surgery

PURPOSE

Although it is well established that physical activity (PA) may partially correct the metabolic and hormonal alterations observed in patients with obesity, knowledge of its impact after bariatric surgery (BS) remains poor. The purpose of this study was to assess the repercussions of physical training on cortisol and testosterone responses in post-BS women.

MATERIALS AND METHODS

According to a randomized clinical trial, a PA group (11 women) started a 3-month physical training 6 weeks after BS, whereas no specific activity was proposed to a control group (9 women). Submaximal exercise (i.e., 30 min at 60% VO₂peak) was performed by all subjects just before and after the 3-month period. Blood samples were taken at rest, after 10, 20, and 30 min of exercise and 10 min of passive recovery for cortisol and testosterone analyses. Blood glucose, blood lactate, and heart rate were assessed at the same time.

RESULTS

Before the program, a significant increase in cortisol, blood lactate, and heart rate was observed in all subjects during the submaximal exercise vs. rest, with no change in blood glucose and testosterone. After vs. before the 3-month period, no modification in any parameter was noted at rest in either group. However, during exercise, lack of cortisol increase and lower heart rate were found in the PA group only, with disappearance of the increase in blood lactate in both groups.

CONCLUSION

Our results show some beneficial effects of physical training on hormonal and physical parameters. Further studies are needed to determine the biological and clinical significance of these adaptations induced by physical training in women after BS.

High levels of FSH before puberty are associated with increased risk of metabolic syndrome during pubertal transition

BACKGROUND

During perimenopause, the rise in serum follicle-stimulating hormone (FSH) is associated with increased adiposity, insulin resistance (IR), and metabolic syndrome (MetS). However, data for the pubertal period, which is characterized by increasing FSH levels and changing body composition, are limited.

OBJECTIVES

To investigate the relationships between FSH and anthropometric changes, IR markers, and development of MetS in the peripubertal period.

METHODS

Uppsala Longitudinal Study of Childhood Obesity (ULSCO) is an ongoing study that aims to understand the factors contributing to childhood obesity and the development of obesity-related diseases. We analysed the subset of participants who were prepubertal at the first visit (n = 95, 77 with obesity). Mean follow-up time was 3.0 ± 1.4 years.

RESULTS

Higher serum FSH levels at the first visit were associated with an increased likelihood of elevation in body mass index (BMI SDS) (p = 0.025, OR = 16.10) and having MetS (p = 0.044, OR = 4.67) at the follow-up. We observed nonlinear relationships between varying serum FSH levels and markers of adiposity and IR, especially in girls. At the first visit, when girls were prepubertal, FSH was negatively associated with BMI (β = -0.491, p = 0.005) and positively associated with sex hormone-binding globulin (SHBG) (β = 0.625, p = 0.002). With the progression of puberty, negative associations between BMI and SHBG disappeared while FSH became positively associated with HOMA-IR (β = 0.678, p = 0.025) and fasting insulin (β = 0.668, p = 0.027).

CONCLUSIONS

Higher serum FSH levels in prepubertal children were associated with an increased risk of MetS development during pubertal transition. Along with nonlinear associations between varying serum FSH levels and IR markers, our results might imply a relationship between FSH and IR of puberty.

Multi-Timescale Rhythmicity of Blood Glucose and Insulin Delivery Reveals Key Advantages of Hybrid Closed Loop Therapy

BACKGROUND

Blood glucose and insulin exhibit coordinated daily and hourly rhythms in people without diabetes (nonT1D). Although the presence and stability of these rhythms are associated with euglycemia, it is unknown if they (1) are preserved in individuals with type 1 diabetes (T1D) and (2) vary by therapy type. In particular, Hybrid Closed Loop (HCL) systems improve glycemia in T1D compared to Sensor Augmented Pump (SAP) therapies, but the extent to which either recapitulates coupled glucose and insulin rhythmicity is not well described. In HCL systems, more rapid modulation of glucose via automated insulin delivery may result in greater rhythmic coordination and euglycemia. Such precision may not be possible in SAP systems. We hypothesized that HCL users would exhibit fewer hyperglycemic event, superior rhythmicity, and coordination relative to SAP users.

METHODS

Wavelet and coherence analyses were used to compare glucose and insulin delivery rate (IDR) within-day and daily rhythms, and their coordination, in 3 datasets: HCL (n = 150), SAP (n = 89), and nonT1D glucose (n = 16).

RESULTS

Glycemia, correlation between normalized glucose and IDR, daily coherence of glucose and IDR, and amplitude of glucose oscillations differed significantly between SAP and HCL users. Daily glucose rhythms differed significantly between SAP, but not HCL, users and nonT1D individuals.

CONCLUSIONS

SAP use is associated with greater hyperglycemia, higher amplitude glucose fluctuations, and a less stably coordinated rhythmic phenotype compared to HCL use. Improvements in glucose and IDR rhythmicity may contribute to the overall effectiveness of HCL systems.

The Relationship between Fat Mass Percentage and Glucose Metabolism in Children and Adolescents: A Systematic Review and Meta-Analysis

To assess the relationship between fat mass percentage (FMP) and glucose metabolism in children aged 0−18 years we performed a systematic review of the literature on Medline/PubMed, SinoMed, Embase and Cochrane Library using the PRISMA 2020 guidelines up to 12 October 2021 for observational studies that assessed the relationship of FMP and glucose metabolism. Twenty studies with 18,576 individuals were included in the meta-analysis. The results showed that FMP was significantly associated with fasting plasma glucose (FPG) (r = 0.08, 95% confidence interval (CI): 0.04−0.13, p < 0.001), fasting plasma insulin (INS) (r = 0.48, 95% CI: 0.37−0.57, p < 0.001), and homeostasis model assessment (HOMA)- insulin resistance (IR) (r = 0.44, 95% CI: 0.33−0.53, p < 0.001). The subgroup analysis according to country or overweight and obesity indicated that these associations remained significant between FMP and INS or HOMA-IR. Our results demonstrated that there is a positive relationship between FMP and FPG. Moreover, subgroup analysis according to country or overweight and obesity indicated that FMP is significantly associated with INS and HOMA-IR. This is the first known systematic review and meta-analysis to determine the associations of FMP with glucose metabolism in children and adolescents.

The Interaction of Obesity and Reproductive Function in Adolescents

Obesity is increasing worldwide, including in pediatrics. Adequate nutrition is required for initiation of menses, and there is a clear secular trend toward earlier pubertal onset and menarche in females in countries around the globe. Similar findings of earlier pubertal start are suggested in males. However, as individuals and populations have crossed into over-nutritional states including overweight and obesity, the effect of excess weight on disrupting reproductive function has become apparent. Hypothalamic hypogonadism and polycystic ovary syndrome are two conditions where reproductive function appears to directly relate to excess weight. Clinical findings in individuals with certain polygenic and monogenic obesity syndromes, which also have reproductive disruptions, have helped elucidate neurologic pathways that are common to both. Clinical endocrinopathies such as hypothyroidism or panhypopituitarism also aide in the understanding of the role of the endocrine system in weight gain. Understanding the intersection of obesity and reproductive function may lead to future therapies which can treat both conditions.

The Association Between Food Addiction and Weight Status in School-Age Children and Adolescents

Background

The association between food addiction (FA) and weight status in children and adolescents remains poorly understood. This study aimed to elucidate the association between FA and weight status using the validated Chinese version of the dimensional Yale Food Addiction Scale for Children 2.0 (dYFAS-C 2.0).

Methods

Participants were enrolled from clinic visitors for regular physical check in a children's hospital. The dYFAS-C 2.0 was translated into Chinese and validated using reliability and validity tests. The participants' body mass index Z score (BMIZ) and waist-to-height ratio (WHtR) were used to characterize weight status. The FA severity was assessed using the translated dYFAS-C 2.0.

Results

Among the 903 children and adolescents enrolled, 426 (47.2%) completed the survey [277 (65%) females and 149 (35%) males]. The Cronbach α of translated dYFAS-C 2.0 was 0.934, and confirmatory factor analysis indicated an acceptable model fit. FA correlated positively with BMIZ and WHtR in the whole sample after adjusting for the effect of gender (p < 0.001). Further analyses showed that the correlation remained significant in participants with BMIZ > 1 (p = 0.006) but not in those with BMIZ ≤ 1 (p = 0.220). However, the correlations between FA and WHtR were statistically significant in both participants with or without abdominal obesity (p < 0.05). The FA could explain 12.1 and 15.8% of variance in BMIZ and WHtR, respectively. The corresponding cutoff points of FA for excessive weight risk were 0.7 (BMIZ) and 0.4 (WHtR).

Conclusion

The dYFAS-C 2.0 has good reliability and validity in the Chinese population. FA is associated with weight status characterized by BMIZ and WHtR, especially in participants with BMIZ > 1 and in those with abdominal obesity.

Clinical Trial Registration

[www.chictr.org.cn], identifier [ChiCTR2100052239].

The role of gonadotropin-releasing hormone neurons in polycystic ovary syndrome

Given the critical central role of gonadotropin-releasing hormone (GnRH) neurons in fertility, it is not surprising that the GnRH neural network is implicated in the pathology of polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility. Although many symptoms of PCOS relate most proximately to ovarian dysfunction, the central reproductive neuroendocrine system ultimately drives ovarian function through its regulation of anterior pituitary gonadotropin release. The typical cyclical changes in frequency of GnRH release are often absent in women with PCOS, resulting in a persistent high-frequency drive promoting gonadotropin changes (i.e., relatively high luteinizing hormone and relatively low follicle-stimulating hormone concentrations) that contribute to ovarian hyperandrogenemia and ovulatory dysfunction. However, the specific mechanisms underpinning GnRH neuron dysfunction in PCOS remain unclear. Here, we summarize several preclinical and clinical studies that explore the causes of aberrant GnRH secretion in PCOS and the role of disordered GnRH secretion in PCOS pathophysiology.

Lower Circulating Sertoli and Leydig Cell Hormone Levels During Puberty in Obese Boys: A Cross-sectional Study

CONTEXT

Alterations in semen characteristics and circulating Sertoli and Leydig cell hormones have been described in obese male adults. Whether hormonal alterations occur before adulthood has not been fully evaluated.

OBJECTIVE

We describe circulating Sertoli and Leydig cell hormone levels in overweight-obese (ow/ob) boys through childhood and adolescence in a cross-sectional study.

METHODS

Monocentric study in the Pediatric Endocrinology Unit of Angers University Hospital. Three hundred and fifty-one obese and overweight boys aged 5-19 years underwent physical examination, dual-energy X-ray absorptiometry for body composition, oral glucose tolerance test on insulin and glucose, and measurements of follicle-stimulating hormone, luteinizing hormone, anti-Müllerian hormone (AMH), inhibin B, testosterone, and estradiol. Hormonal levels were compared with normative data obtained from 652 healthy nonoverweight nonobese boys of similar age or Tanner stage.

RESULTS

Median inhibin B and testosterone levels during puberty were significantly lower in ow/ob than in healthy boys (1) from age >12 years and thereafter for inhibin B, and (2) from age >14 years and thereafter for testosterone. At Tanner stages 4 and 5, 26%, 31%, and 18% of inhibin B, testosterone, and AMH values were below the 5th percentile in ow/ob subjects (P < .01). In multiple regression analyses, estradiol and total bone mineral density Z-score were negative predictors of inhibin B, fat mass percentage was a negative predictor of testosterone, and insulin was a negative predictor of AMH.

CONCLUSION

Lower Sertoli and Leydig cell hormone levels during puberty were observed in the ow/ob boys.

Profile of Daughters and Sisters of Women With Polycystic Ovary Syndrome: The Role of Proband's Glucose Tolerance

CONTEXT

First-degree relatives of women with polycystic ovary syndrome (PCOS) present hormonal and metabolic alterations compared to girls unrelated to PCOS. It is unknown whether glucose intolerance in the PCOS proband confers a more severe metabolic predisposition on their first-degree relatives.

OBJECTIVE

To determine whether glucose tolerance status in women with PCOS is associated with worsened glucose metabolism and sex hormone levels in their peripubertal daughters or sisters.

DESIGN

Cross-sectional study.

SETTING

Seven academic centers in North America, South America, and Europe.

PATIENTS

Sixty-four pairs of women with PCOS and their daughters or younger sisters aged between 8 and 14 years were recruited. Twenty-five mothers or older sisters with PCOS were glucose intolerant (GI) and 39 were normal glucose tolerant (NGT).

MAIN OUTCOME MEASURES

Beta-cell function estimated by the insulin secretion-sensitivity index-2 (ISSI-2) during an oral glucose tolerance test and by the disposition index during a frequently sampled IV glucose tolerance test. Free testosterone and 17-hydroxyprogesterone (17-OHP) levels.

RESULTS

Being related to a GI PCOS proband was associated with a lower ISSI-2 (P-value = 0.032) after adjusting for ethnicity, body mass index z-score, and pubertal stage. They also had higher free testosterone (P-value = 0.011) and 17-OHP levels compared to girls with an NGT proband, the latter becoming significant after adjusting for confounders (P-value = 0.040).

CONCLUSIONS

Compared to first-degree female relatives of women with PCOS and NGT, first-degree relatives of women with PCOS and GI display lower beta-cell function and hyperandrogenemia, putting them at higher risk of GI and PCOS development.

Effect of Sex Hormone-Binding Globulin on Polycystic Ovary Syndrome: Mechanisms, Manifestations, Genetics, and Treatment

Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases causing infertility in women of childbearing age. It is characterized by hyperandrogenemia (HA), chronic anovulation, and polycystic ovary morphology (PCOM). Most women with PCOS have metabolic abnormalities. Sex hormone-binding globulin (SHBG), a transport carrier that binds estrogen and androgens and regulates their biological activity, is usually used as an indicator of hyperandrogenism in women with PCOS. Low serum SHBG levels are considered a biomarker of metabolic abnormalities and are associated with insulin resistance (IR), HA, and abnormal glucose and lipid metabolism in PCOS patients. SHBG is also related to the long-term prognosis of PCOS, whereas SHBG gene polymorphism is associated with PCOS risk. In addition, the administration of metformin (MET), glucagon-like peptide-1 receptor agonists (GLP-1 RAs), thiazolidinediones (TZDs), compound oral contraceptives (COCs), as well as nutrient supplements such as inositol (MI), vitamin D, and synbiotics can regulate SHBG levels to ameliorate PCOS complications and improve prognosis. This review focuses on the interaction between SHBG and various PCOS complications as well as the regulation of SHBG by various drugs and nutrients and its therapeutic effects on PCOS.

Spectrum of Phenotypes and Causes of Type 2 Diabetes in Children

Several factors, including genetics, family history, diet, physical activity, obesity, and insulin resistance in puberty, appear to increase the risk of type 2 diabetes in youth. Youth-onset type 2 diabetes is often thought of as a single entity but rather exists as a spectrum of disease with differences in presentation, metabolic characteristics, clinical progression, and complication rates. We review what is currently known regarding the risks associated with developing type 2 diabetes in youth. Additionally, we focus on the spectrum of phenotypes of pediatric type 2 diabetes, discuss the pathogenic underpinnings and potential therapeutic relevance of this heterogeneity, and compare youth-onset type 2 diabetes with type 1 diabetes and adult-onset type 2 diabetes. Finally, we highlight knowledge gaps in prediction and prevention of youth-onset type 2 diabetes.

Early and precocious puberty during the COVID-19 pandemic

During the year 2020, the COVID-19 pandemic rapidly became a severe health emergency worldwide. In order to contrast the spread of the novel SARS-CoV-2, many countries implemented extraordinary restrictive measures, such as a strict lockdown and school closures. The pandemic had a great impact on children and adolescents' daily life, leading to a much more sedentary lifestyle, to larger use of electronic devices and to an increase in stress-related symptoms. These conspicuous changes acted as disruptors of children's normal development. Since the beginning of the pandemic, many studies reported an increase in the number of precocious puberty cases as well as a faster progression rate of puberty itself, if compared to the pre-pandemic years. In this review, our aim was to evaluate the incidence of new cases of early and precocious puberty during the COVID-19 pandemic, analyzing variations in the timing of puberty and in pubertal progression rate, and to investigate the role of environmental and lifestyle factors during the pandemic in modulating the physiopathology of pubertal development. While a direct effect of SARS-CoV-2 infection remains, at the moment, a remote hypothesis, both physical and psychological factors related to the pandemic seem to have a role in triggering GnRH pulsatile secretion leading to earlier pubertal onset. It is indeed important to stress the need to clarify the exact role of COVID-19 in early pubertal onset comparing data from all over the world; long-term comprehensive studies are also pivotal to explain whether this phenomenon will continue while we resume pre-pandemic habits.

Association of Obesity and Body Fat Percentage with Pubertal State in Six- to Nine-Year-Old Chinese Females

Background: An early trend in the mean age of pubertal onset appears in adolescents, but the association between body fat percentage (BF%) of children and precocious puberty is unclear. The aim of the study was to analyze the association of sexual development with BF% in girls. Methods: A total of 407 females were included in this cross-sectional study. BF% was measured by Inbody S10, International Obesity Task Force was used to judge overweight or obesity, and early puberty was defined as a younger age than the median age in each of the pubertal Tanner stages. Logistic regression analysis was used to test relationships between pubertal states and independent variables, including age, weight, waist circumference (WC), type of school, and residency. Results: Females with early puberty exhibited higher anthropometry data (such as weight, BMI, BF%) than females with normal maturation (p < 0.001). Weight, BMI, WC, BF% residency, and school type were related to pubertal state (p < 0.001). Females with higher BF% were more likely to exhibit early puberty (odds ratio = 1.138, 95% confidence interval = 1.046-1.237). The students who lived in urban areas and studied in public schools had a lower risk of early puberty. Moreover, BF% continuously increased with age in 6- to 9-year-old girls. Conclusions: Females with higher BF% may be more likely to exhibit early puberty. In future studies, more research is needed to analyze this mechanism of how BF% influences puberty development.

Obesity is a risk factor for central precocious puberty: a case-control study

BACKGROUND

Obesity is an important underlying cause of central precocious puberty (CPP), but previous large studies are flawed by using just age and breast examination to diagnose CPP. We aimed to determine whether overweight and obesity in childhood increases hormonally diagnosed CPP.

METHODS

Our retrospective, case-control study recruited 846 children diagnosed as having CPP and randomly sampled 1650 healthy control subjects in Xingtai Third Hospital in China between November 2018 and March 2021. Information was obtained from an electronic medical record and questionnaire investigated in the outpatient visit. Observations were made before the a priori hypothesis. Unconditional logistic regression for analysis was used to determine whether overweight and obesity status and duration of overweight/obesity were associated with CPP.

RESULTS

Overweight and obesity were significantly associated with increased odds of CPP among girls, even after adjusting for birth weight, exclusive breastfeeding for 6 month, household income, maternal overweight, paternal overweight, and maternal menarche age (overweight: the adjusted odds ratio (aOR) (95%CI): 1.92 (1.16, 3.24), p = 0.02; obesity: aOR (95%CI): 1.78 (1.13, 3.48), p = 0.03). Furthermore, the effects of overweight and obesity were significant when ongoing for 1 to 2 years, 2 to 3 years, and greater than 3 years, but not at less than 1 year. For boys, association between obesity and increased odds of CPP was observed (aOR (95%CI): 1.68 (1.09, 3.75), p = 0.03). The effects of overweight and/or obesity were only significant when ongoing for greater than 2 years.

CONCLUSIONS

Prolonged overweight and obesity in early childhood may be risk factors for CPP, especially in girls. Weight loss might be an important approach for the prevention of precocious puberty in children.

Genetic Risk Score for Type 2 Diabetes and Traits Related to Glucose-Insulin Homeostasis in Youth: The Exploring Perinatal Outcomes Among Children (EPOCH) Study

OBJECTIVE

The metabolic phenotype of youth-onset type 2 diabetes (T2D) differs from that of adult-onset T2D, but little is known about genetic contributions. We aimed to evaluate the association between a T2D genetic risk score (GRS) and traits related to glucose-insulin homeostasis among healthy youth.

RESEARCH DESIGN AND METHODS

We used data from 356 youth (mean age 16.7 years; 50% female) in the Exploring Perinatal Outcomes Among Children (EPOCH) cohort to calculate a standardized weighted GRS based on 271 single nucleotide polymorphisms associated with T2D in adults. We used linear regression to assess associations of the GRS with log-transformed fasting glucose, 2-h glucose, HOMA of insulin resistance (HOMA-IR), oral disposition index, and insulinogenic index adjusted for age, sex, BMI z score, in utero exposure to maternal diabetes, and genetic principal components. We also evaluated effect modification by BMI z score, in utero exposure to maternal diabetes, and ethnicity.

RESULTS

Higher weighted GRS was associated with lower oral disposition index (β = -0.11; 95% CI -0.19, -0.02) and insulinogenic index (β = -0.08; 95% CI -0.17, -0.001), but not with fasting glucose (β = 0.01; 95% CI -0.01, 0.02), 2-h glucose (β = 0.03; 95% CI -0.0004, 0.06), or HOMA-IR (β = 0.02; 95% CI -0.04, 0.07). BMI z score and in utero exposure to maternal diabetes increased the effect of the GRS on glucose levels.

CONCLUSIONS

Our results suggest that T2D genetic risk factors established in adults are relevant to glucose-insulin homeostasis in youth and that maintaining a healthy weight may be particularly important for youth with high genetic risk of T2D.

Oxidative stress promotes hyperandrogenism by reducing sex hormone-binding globulin in polycystic ovary syndrome

OBJECTIVE

To determine the relationships between circulating sex hormone-binding globulin (SHBG) and oxidized low-density lipoprotein (ox-LDL), total oxidant status, total antioxidant capacity, oxidative stress index, malondialdehyde, and the high-density lipoprotein (HDL) inflammatory index in patients with polycystic ovary syndrome (PCOS) and to investigate the effect of oxidative stress on the expression of SHBG and its mechanism in HepG2 cells.

DESIGN

Cross-sectional study.

SETTING

University hospital.

PATIENT(S)

A total of 533 women with PCOS and 292 control women were included.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Circulating SHBG, hormones, and metabolic and oxidative stress indices were determined in all subjects. The effects of ox-LDL and ox-HDL on the mRNA and protein expression of SHBG and related transcription factors were observed in HepG2 cells.

RESULT(S)

The HDL inflammatory index, total oxidant status, oxidative stress index, and malondialdehyde levels were significantly higher in the three PCOS subgroups with different SHBG levels than in the controls. The ox-LDL and total antioxidant capacity were higher in the PCOS subgroups with SHBG levels <75th percentile compared with the controls or the PCOS subgroup with SHBG levels ≥75th percentile. In HepG2 cells, the SHBG concentration in the culture supernatant, the mRNA levels of SHBG and hepatocyte nuclear factor-4α (HNF-4α), and the protein levels of HNF-4α were significantly lower in ox-LDL- and ox-HDL-treated cells than in the control cells and lipoprotein-treated cells.

CONCLUSION(S)

Oxidative stress inhibits the expression and secretion of SHBG by downregulating HNF-4α in vitro and may be an important factor promoting the occurrence of hyperandrogenemia in PCOS.

Sex steroids and adiposity in a prospective observational cohort of youth

OBJECTIVE

Adiposity, particularly visceral adipose tissue (VAT), predicts adverse cardiovascular risk factor profiles in children as well as adults. Although endogenous sex steroids likely influence VAT in adults, such an association has not been established in youth. The association between childhood and adolescent sex steroids with adiposity, specifically VAT, was examined before and after adjustment for other hormone changes.

METHODS

These analyses examined longitudinal associations between sex steroids (testosterone, estradiol, dehydroepiandrosterone [DHEA]) and magnetic resonance imaging assessments of VAT in 418 children, 49% of whom were non-White, at approximately 10 years old at Visit 1 (V1) and 17 years old at Visit 2 (V2). Linear mixed effects models adjusted for maternal education, household income, child caloric intake, physical activity, fasting insulin and leptin, and hepatic fat fraction. Differences in associations by race and pubertal stage were also assessed.

RESULTS

At V1, mean body mass index (BMI) for boys was 19.1 (4.7) kg/m2 and for girls was 18.5 (4.1) kg/m2. At V2, mean BMI for boys was 23.7 (5.5) kg/m2 and for girls was 23.6 (5.7) kg/m2. For each ng/dl (0.035 nmol/L) increase in testosterone at V1, there was a 0.25 cm2 increase in concurrent and future VAT in non-White (p = 0.04) but not White girls (p = 0.78). Higher levels of testosterone and DHEA at V1 were associated with greater concurrent and future VAT at V2. These associations were consistent regardless of pubertal stage. In boys, higher testosterone predicted higher future VAT but lower concurrent VAT. Estradiol and DHEA did not predict future VAT in boys. In girls, DHEA predicted future subcutaneous adipose tissue (SAT), and no sex steroids predicted future SAT in boys.

CONCLUSIONS

Testosterone levels predict VAT in boys and girls, and DHEA predicts VAT in girls, even after adjustment for other hormone changes.

The link between obesity and puberty: what is new?

PURPOSE OF REVIEW

The objective of this review is to assess the most recent literature on pubertal trends in boys and girls as well as evaluate genetic, epigenetic, and environmental factors implicated in the timing of pubertal progression.

RECENT FINDINGS

Recent studies confirm the previously described link between increased adiposity and earlier onset of puberty in girls, and more recent studies shed light onto the previously unclear situation in boys as a preponderance of recent longitudinal studies suggests that increased adiposity is linked with earlier pubertal timing also in boys. Discoveries of novel pathways highlights the complexity of pubertal development and suggest mechanistic links between nutrition, obesity, leptin, insulin resistance, and puberty. Furthermore, genetic and epigenetic variants can be linked to early puberty. Other factors, such as prenatal and postnatal environment, gut microbiota, and endocrine-disrupting chemicals have also been linked to both obesity and earlier puberty.

SUMMARY

Understanding how the interactions of these factors contribute the relationship between obesity and early pubertal onset is crucial as early puberty has been linked with long-term consequences, such as short stature, earlier type 2 diabetes, cardiovascular disease, and poor psychological and behavioral outcomes.

Independent and combined associations of urinary heavy metals exposure and serum sex hormones among adults in NHANES 2013-2016

Accumulating evidences indicated that heavy metals may disrupt human sex hormones. However, the combined effects of heavy metals on sex hormones remain to be clarified. To explore the independent and combined associations between heavy metal exposure and serum sex hormones among adults, data of 2728 adults from the National Health and Nutrition Examination Survey (NHANES) was applied. We examined independent and combined associations of fourteen urinary heavy metals and three serum sex steroid hormones (total testosterone (TT), estradiol (E2) and sex hormone-binding globulin (SHBG)). Multivariate linear regression was used to evaluate the independent associations between metal exposure and sex hormone alterations. Principle component analysis -weighted quantile sum regression (PCA-WQSR) model was performed to estimate the combined associations in our individuals. In the co-exposure model, we determined that weighted quantile sum (WQS) index of industrial pollutants was negatively associated with E2 in females (WQS Percent change_8-metal = -20.6%; 95% CI: -30.1%, -9.96%), while in males WQS index of water pollutants was negatively related to SHBG (WQS Percent change_8-metal = -5.35%; 95% CI: -9.88%, -0.598%). Cadmium (Cd), tin (Sn) and lead (Pb) were the dominating metals of female E2-negative association while Ba was the leading contributor related to male SHBG reduction, which was consistent with the results of multivariate linear regression. Additionally, in postmenopausal women, the associations of E2 decrease with heavy metal co-exposure remained significant while Cd and monomethylarsonic acid (MMA) were identified as hazardous metals in the mixture. We concluded that the exposure to heavy metals was associated with human sex hormone alterations in independent or combined manners. Considering the design of NHANES study, further studies from other national-representative surveys are necessary.

Dynamic alterations in linear growth and endocrine parameters in children with obesity and height reference values

BACKGROUND

Obesity can affect linear growth of children but there is uncertainty regarding the dynamics and potential causes.

METHODS

In the population-based LIFE Child and the obesity-enriched Leipzig Obesity Childhood cohorts (8,629 children, 37,493 measurements), recruited from 1999 to 2018 in Germany, we compared height, growth, and endocrine parameters between normal-weight and children with obesity (0-20 years). Derived from the independent German CrescNet registry (12,703 children) we generated height reference values specific for children with obesity (data collected from 1999 to 2020).

FINDINGS

Children with obesity were significantly taller than normal-weight peers, differing at maximum by 7·6 cm (1·4 height, standard deviation scores or SDS) at age 6-8 years. Already at birth, children with obesity were slightly taller and thereafter had increased growth velocities by up to 1·2 cm/year. This growth acceleration was unrelated to parental height, but was accompanied by increased levels of insulin-like growth factor-1 (IGF-1), insulin and leptin. During puberty, children with obesity showed a catch-down in height SDS. The reduction in pubertal growth velocity by up to 25% coincided with a decrease in levels of IGF-1 (by 17%) and testosterone (by 62%) in boys and estradiol (by 37%) in girls. We confirmed these alterations in growth in the independent CrescNet cohort and furthermore provide height reference values for children with obesity for open access.

INTERPRETATION

Dynamics of linear growth are altered distinctively in different developmental phases in children with obesity. Early emergence before other profound comorbidities implies predisposition, environmental, and/or endocrine factors affecting growth in early life. Height reference values for children with obesity may enhance the precision of clinical health surveillance.

FUNDING

German Research Foundation, German Diabetes Association, EU, ESF, ERDF, State of Saxony, ESPE, Hexal, Novo Nordisk, Pfizer Pharma.

Two-Year Treatment With Metformin During Puberty Does Not Preserve β-Cell Function in Youth With Obesity

CONTEXT

Youth-onset type 2 diabetes is a disease of pubertal onset, associated with additional burden of pubertal insulin resistance on the β-cell.

OBJECTIVE

Evaluate the impact of metformin treatment during puberty, a critical window of cardiometabolic change, on insulin sensitivity (Si) and compensatory β-cell response in youth with obesity.

SETTING

Pediatric academic hospital clinical translational research center.

PARTICIPANTS

Healthy youth in early puberty [Tanner stage (T) 2-3] with normoglycemia and obesity (n = 44).

INTERVENTION

Double-blinded placebo-control trial of metformin during puberty (until T5).

MAIN OUTCOME MEASURES

Insulin sensitivity (Si), insulin response [acute insulin response to glucose (AIRg)], and disposition index (DI), estimated from frequently sampled intravenous glucose tolerance testing; body fat (dual X-ray absorptiometry); and other laboratory parameters, collected at baseline, T4, and T5. Placebo-subtracted treatment effect was calculated using linear mixed models.

RESULTS

At T5, metformin treatment, adjusting for sex, race, and baseline value, was associated with improved BMI z-score (-0.44 ± 0.16, P = 0.02), percentage body fat (%body fat; -3.4 ± 1.2%, P = 0.06), and waist circumference (-11.3 ± 3.2cm, P = 0.003). There were no significant treatment effects at T5 on Si or secretion: Si (0.85 ± 0.87 × 10-4/min-1/μIU/mL, P = 0.34), AIRg (-259 ± 386 μIU/mL, P = 0.51), or DI (508 ± 802 × 10-4/min-1, P = 0.53). High baseline DI predicted longitudinal decline in DI.

CONCLUSIONS

Two years of metformin treatment in obese youth during puberty improved BMI and body fat, but not Si or β-cell function. Of note, high DI in early puberty may be predictive of later decline in DI. Further studies are needed to develop strategies for preservation of β-cell function in youth at risk for type 2 diabetes.

Polycystic Ovary Syndrome in Insulin-Resistant Adolescents with Obesity: The Role of Nutrition Therapy and Food Supplements as a Strategy to Protect Fertility

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in young reproductive-aged women. PCOS is often associated with obesity and impairs reproductive health. Even though several theories have been proposed to explain the pathogenic mechanism of PCOS, the role of insulin resistance (IR) as a key etiological component, independently of (but amplified by) obesity, is well recognized. The consequent hyperinsulinemia activates excessive ovarian androgen production, leading to PCOS. Additionally, the state of chronic inflammation related to obesity impacts ovarian physiology due to insulin sensitivity impairment. The first-line treatment for adolescents with obesity and PCOS includes lifestyle changes; personalized dietary interventions; and, when needed, weight loss. Medical nutrition therapy (MNT) and the use of specific food supplements in these patients aim at improving symptoms and signs, including insulin resistance and metabolic and reproductive functions. The purpose of this narrative review is to present and discuss PCOS in adolescents with obesity, its relationship with IR and the role of MNT and food supplements in treatment. Appropriate early dietary intervention for the management of adolescents with obesity and PCOS should be considered as the recommended approach to restore ovulation and to protect fertility.

Early menarche is associated with insulin-resistance and non-alcoholic fatty liver disease in adolescents with obesity

OBJECTIVES

Recent evidence linked early menarche to a higher risk of insulin-resistance (IR) and nonalcoholic fatty liver disease (NAFLD) in adulthood. We aimed to evaluate the impact of early menarche on glucose derangements and NAFLD in a sample of Italian adolescents with obesity.

METHODS

Anthropometric and biochemical evaluations were conducted in all the enrolled 318 obese patients (mean age 12.31 ± 2.95 years). NAFLD was defined by the presence of ultrasound detected liver steatosis and/or alanine transaminase (ALT) levels >40 IU/L.

RESULTS

Patients with early menarche showed both higher homeostasis model assessment of insulin-resistance (HOMA-IR) (p=0.008) and ALT (p=0.02) values, an increased prevalence of NAFLD (p=0.001), and lower Matsuda and Insulinogenic Index (IGI) values than the other obese patients. The association between early menarche and both ALT and Matsuda Index remained significant in General Linear Models (GLMs) in which respectively body mass index standard deviation score (BMI-SDS) and Matsuda Index, and BMI-SDS were included as covariates. Patients with early menarche also showed a higher risk of both HOMA-IR>3 (OR 1.69, CI 1.05-2.70, p=0.02) and NAFLD (OR 1.10, CI 1.01-1.21, p=0.03).

CONCLUSIONS

Girls with obesity presenting early menarche showed higher HOMA-IR levels, lower Matsuda Index and IGI values, and higher risk of NAFLD compared to girls without early menarche.

Longitudinal Investigation of Pubertal Milestones and Hormones as a Function of Body Fat in Girls

CONTEXT

Epidemiologic studies have demonstrated that overweight/obese girls (OW/OB) undergo thelarche and menarche earlier than normal weight girls (NW). There have been no longitudinal studies to specifically investigate how body weight/fat affects both clinical and biochemical pubertal markers in girls.

OBJECTIVE

To investigate the effect of total body fat on reproductive hormones and on the maturation of estrogen-sensitive tissues during puberty in girls.

METHODS

Ninety girls (36 OW/OB, 54 NW), aged 8.2 to 14.7 years, completed 2.8 ± 1.7 study visits over 4 years. Visits included dual-energy x-ray absorptiometry to calculate total body fat (TBF), Tanner staging, breast ultrasound for morphological staging (BMORPH; A-E), pelvic ultrasound, hormone tests, and assessment of menarchal status. The effect of TBF on pubertal markers was determined using a mixed, multistate, or Cox proportional hazards model, controlling for baseline BMORPH.

RESULTS

NW were older than OW/OB (11.3 vs 10.2 years, P < .01) at baseline and had more advanced BMORPH (P < .01). Luteinizing hormone, estradiol, and ovarian and uterine volumes increased with time with no effect of TBF. There was a time × TBF interaction for follicle-stimulating hormone, inhibin B, estrone, total and free testosterone, and androstenedione: Levels were initially similar, but after 1 year, levels increased in girls with higher TBF, plateaued in girls with midrange TBF, and decreased in girls with lower TBF. Girls with higher TBF progressed through BMORPH stage D more slowly but achieved menarche earlier than girls with lower TBF.

CONCLUSION

In late puberty, girls with higher TBF demonstrate differences in standard hormonal and clinical markers of puberty. Investigation of the underlying causes and clinical consequences of these differences in girls with higher TBF deserves further study.

Body Composition and Markers of Cardiometabolic Health in Transgender Youth on Gonadotropin-Releasing Hormone Agonists

Purpose: Up to 1.8% of youth identify as transgender; many will be treated with a gonadotropin-releasing hormone agonist (GnRHa). The impact of GnRHa on insulin sensitivity and body composition in transgender youth is understudied. We aimed to evaluate differences in insulin sensitivity and body composition in transgender youth on GnRHa therapy compared with cisgender youth. Methods: Transgender participants were matched to cisgender participants on age, body mass index, and sex assigned at birth. Transgender males (n=9, ages 10.1-16.0 years) on GnRHa (mean±standard deviation duration of exposure: 20.9±19.8 months) were compared with cisgender females (n=14, ages 10.6-16.2). Transgender females (n=8, ages 12.6-16.1) on GnRHa (11.3±7 months) were compared with cisgender males (n=17, ages 12.5-15.5). Differences in insulin sensitivity (1/[fasting insulin], homeostatic model of insulin resistance [HOMA-IR]), glycemia (hemoglobin A1C [HbA1c], fasting glucose), and body composition (dual-energy X-ray absorptiometry) were evaluated using a mixed linear regression model. Results: Transgender males had lower 1/fasting insulin and higher HOMA-IR (p=0.031, p=0.01, respectively), fasting glucose (89±4 vs. 79±13 mg/dL, p=0.012), HbA1c (5.4±0.2 vs. 5.2±0.2%, p=0.039), and percent body fat (36±7 vs. 32±5%, p=0.042) than matched cisgender females. Transgender females had lower 1/fasting insulin and higher HOMA-IR (p=0.028, p=0.035), HbA1c (5.4±0.1% vs. 5.1±0.2%, p=0.007), percent body fat (31±9 vs. 24±10%, p=0.002), and lower percent lean mass (66±8 vs. 74±10%, p<0.001) than matched cisgender males. Conclusion: Transgender youth on a GnRHa have lower estimated insulin sensitivity and higher glycemic markers and body fat than cisgender controls with similar characteristics. Longitudinal studies are needed to understand the significance of these changes. Clinical Trial.gov ID: NCT02550431.

The NIMH Intramural Longitudinal Study of the Endocrine and Neurobiological Events Accompanying Puberty: Protocol and rationale for methods and measures

Delineating the relationship between human neurodevelopment and the maturation of the hypothalamic-pituitary-gonadal (HPG) axis during puberty is critical for investigating the increase in vulnerability to neuropsychiatric disorders that is well documented during this period. Preclinical research demonstrates a clear association between gonadal production of sex steroids and neurodevelopment; however, identifying similar associations in humans has been complicated by confounding variables (such as age) and the coactivation of two additional endocrine systems (the adrenal androgenic system and the somatotropic growth axis) and requires further elucidation. In this paper, we present the design of, and preliminary observations from, the ongoing NIMH Intramural Longitudinal Study of the Endocrine and Neurobiological Events Accompanying Puberty. The aim of this study is to directly examine how the increase in sex steroid hormone production following activation of the HPG-axis (i.e., gonadarche) impacts neurodevelopment, and, additionally, to determine how gonadal development and maturation is associated with longitudinal changes in brain structure and function in boys and girls. To disentangle the effects of sex steroids from those of age and other endocrine events on brain development, our study design includes 1) selection criteria that establish a well-characterized baseline cohort of healthy 8-year-old children prior to the onset of puberty (e.g., prior to puberty-related sex steroid hormone production); 2) temporally dense longitudinal, repeated-measures sampling of typically developing children at 8-10 month intervals over a 10-year period between the ages of eight and 18; 3) contemporaneous collection of endocrine and other measures of gonadal, adrenal, and growth axis function at each timepoint; and 4) collection of multimodal neuroimaging measures at these same timepoints, including brain structure (gray and white matter volume, cortical thickness and area, white matter integrity, myelination) and function (reward processing, emotional processing, inhibition/impulsivity, working memory, resting-state network connectivity, regional cerebral blood flow). This report of our ongoing longitudinal study 1) provides a comprehensive review of the endocrine events of puberty; 2) details our overall study design; 3) presents our selection criteria for study entry (e.g., well-characterized prepubertal baseline) along with the endocrinological considerations and guiding principles that underlie these criteria; 4) describes our longitudinal outcome measures and how they specifically relate to investigating the effects of gonadal development on brain development; and 5) documents patterns of fMRI activation and resting-state networks from an early, representative subsample of our cohort of prepubertal 8-year-old children.

Polycystic Ovary Syndrome: Ontogeny in Adolescence

The pathophysiology of symptomatic polycystic ovary syndrome (PCOS) often unfolds across puberty, but the ontogeny of PCOS is difficult to study because, in general, its pathophysiology is well entrenched before the diagnosis can be confirmed. However, the study of high-risk groups (daughters of women with PCOS, girls with premature pubarche, and girls with obesity) can offer insight in this regard. Available data support the hypothesis that the pubertal development of PCOS involves various combinations of genetic predisposition, intrauterine programming, hyperinsulinism, and numerous other abnormalities that provoke reproductive symptoms (eg, hyperandrogenism, ovulatory dysfunction) in response to the pubertal increase in gonadotropin secretion.

Puberty Is Associated with a Rising Hemoglobin A1c, Even in Youth with Normal Weight

Our objective was to explore the longitudinal trajectory of hemoglobin A1c (HbA1c) in well-characterized youth (n = 84) with normal weight and obesity during puberty. HbA1c rose from early puberty to Tanner stage 5, even in healthy, normal weight youth, revealing important implications for defining normal glycemia and prediabetes in adolescents.

Comparison of Growth Velocity Among School Age Children With Different Body Mass Index From Childhood Into Early Adolescence in Hualien County, Taiwan: A Retrospective Cohort Study

Objective: This study aimed to investigate the contribution of high body mass index (BMI) to growth velocity among school-aged children who remained in the same BMI categories for a 6-year period. Methods: This retrospective cohort study included children who enrolled in the school year 2009 and remained in the same BMI categories during their 1st, 4th, and 7th grades (6-7, 9-10, 12-13 years of age). Annual linear growth velocity and weight gain were calculated and compared between sexes, BMI groups, and different times. Risk analysis and repeated measures analysis of variance were performed to identify the impact of BMI on growth velocity. Results: Of the 1,637 subjects, 53.0% were male, and 2.5% and 10.9% belonged to BMI groups of overweight and obese, respectively. In students between 6 and 13 years of age, obesity was associated with higher annual weight gain and height gain. Risk analysis showed that obese subjects had higher linear growth velocity than normal BMI groups of both sexes between 6 and 9 years of age. Unexpectedly, overweight and obese girls between 9 and 13 years of age had less linear growth velocity than underweight girls at the same interval. Repeated measures analysis of variance in both sexes showed a significant statistical association between BMI and different times of growth. However, the effect was less in girls between 9 and 13 years of age. Conclusion: Puberty may dominate over BMI as the main contributor to high growth velocity in girls with underweight BMI emerging into pubertal age.

Classic and Novel Sex Hormone Binding Globulin Effects on the Cardiovascular System in Men

In men, 70% of circulating testosterone binds with high affinity to plasma sex hormone binding globulin (SHBG), which determines its bioavailability in their target cells. In recent years, a growing body of evidence has shown that circulating SHBG not only is a passive carrier for steroid hormones but also actively regulates testosterone signaling through putative plasma membrane receptors and by local expression of androgen-binding proteins apparently to reach local elevated testosterone concentrations in specific androgen target tissues. Circulating SHBG levels are influenced by metabolic and hormonal factors, and they are reduced in obesity and insulin resistance, suggesting that SHBG may have a broader clinical utility in assessing the risk for cardiovascular diseases. Importantly, plasma SHBG levels are strongly correlated with testosterone concentrations, and in men, low testosterone levels are associated with an adverse cardiometabolic profile. Although obesity and insulin resistance are associated with an increased incidence of cardiovascular disease, whether they lead to abnormal expression of circulating SHBG or its interaction with androgen signaling remains to be elucidated. SHBG is produced mainly in the liver, but it can also be expressed in several tissues including the brain, fat tissue, and myocardium. Expression of SHBG is controlled by peroxisome proliferator-activated receptor γ (PPARγ) and AMP-activated protein kinase (AMPK). AMPK/PPAR interaction is critical to regulate hepatocyte nuclear factor-4 (HNF4), a prerequisite for SHBG upregulation. In cardiomyocytes, testosterone activates AMPK and PPARs. Therefore, the description of local expression of cardiac SHBG and its circulating levels may shed new light to explain physiological and adverse cardiometabolic roles of androgens in different tissues. According to emerging clinical evidence, here, we will discuss the potential mechanisms with cardioprotective effects and SHBG levels to be used as an early metabolic and cardiovascular biomarker in men.

Connections Between Obesity and Puberty: Invited by Manuel Tena-Sempere, Cordoba

The relationship between obesity and puberty remains controversial. Whereas cross-sectional and longitudinal studies show a clear shift toward earlier puberty in obese girls, the trend in obese boys remains less obvious. Overweight boys mature earlier whereas obese boys mature later compared to healthy weight boys. Newer epidemiologic studies attempt to address these knowledge gaps. This review provides a detailed overview of the recent literature regarding secular trends in pubertal onset and tempo, and the connection with obesity. Additionally, this review summarizes potential mediators that permit obesity to promote early puberty. Other factors such as socioeconomic status, in utero exposures, nutritional, and even endocrine disrupting chemicals can cause perturbation of both metabolism and the endocrine axis that can ultimately have effects on pubertal development.

Age at menopause, body mass index, and risk of type 2 diabetes mellitus in postmenopausal Chinese women: The Henan Rural Cohort study

BACKGROUND AND AIM

The present study was conducted to explore the stratified and joint effects of age at menopause and body mass index (BMI) with the risk of type 2 diabetes mellitus (T2DM) in Chinese rural adults.

METHODS AND RESULTS

A total of 15,406 postmenopausal Chinese women were included in this study. Multivariable logistic regression analysis was used to quantify the stratified and joint effects of age at menopause and BMI on T2DM. Overall, the mean age at menopause and BMI was 48.8 ± 4.7 years and 25.1 ± 3.6 kg/m², respectively. In general, data suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, later menopause had a higher risk of T2DM (OR, 1.52; 95% CI, 1.16-2.01); 3) the risk of T2DM was higher only in patients with early or normal age at menopause and BMI ≥ 24, with 0R (95% CI) of (1.58, 1.28-1.94) and (1.48, 1.31-1.67), respectively.

CONCLUSION

Our findings suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, a higher risk of T2DM was found only in those with later menopause; 3) women with later menopause had a higher risk of T2DM, irrespective of BMI; 4) in patients with early or normal age at menopause, a higher risk of T2DM was found only in patients with BMI ≥ 24.

THE CHINESE CLINICAL TRIAL REGISTRATION

ChiCTR-OOC-1500669(URL:http://www.chictr.org.cn/showproj.aspx?proj=11375).

The Impact of Obesity On Insulin Sensitivity and Secretion During Pubertal Progression: A Longitudinal Study

CONTEXT

Physiologic changes in glucose metabolism are well-described to occur during puberty. However, there are important gaps in understanding the interaction between obesity and the normal physiologic changes during puberty, as well as how these changes could contribute to the increased risk of comorbidities, such as type 2 diabetes and dyslipidemia, in youth with obesity.

OBJECTIVE

The objective of this study was to compare longitudinal changes in insulin sensitivity (Si) and secretion during pubertal progression in youth with obesity versus those with normal weight.

DESIGN

Longitudinal observational study evaluating youth from early puberty (Tanner [T]2-T3) until puberty completion (T5).

SETTING

Pediatric academic hospital Clinical Translational Research Center.

PARTICIPANTS

Pubertal youth with normal weight (n = 47; 22 female, 25 male) and obesity (n = 37; 23 female, 14 male).

MAIN OUTCOME MEASURES

Si, insulin response (acute insulin response to glucose, AIRg) and disposition index (DI) by intravenous glucose tolerance test at baseline (T2-T3), T4, and T5.

RESULTS

Youth with obesity had significantly lower Si and higher AIRg at each time point (P < 0.001), but DI was similar between the groups. There were no group differences in trajectory of Si, AIRg or DI over time. Leptin, insulin-like growth factor-1, and obesity were most strongly associated with Si and AIRg at all time points.

CONCLUSIONS

Obesity significantly impacts Si during puberty, even at the earliest stages. However, in general, obese youth have adequate β-cell compensation for the significantly reduced Si of puberty. Future studies are needed to better predict the subset of youth who fail to maintain β-cell compensation during puberty.

Body Composition and Markers of Cardiometabolic Health in Transgender Youth Compared With Cisgender Youth

CONTEXT

As many as 1.8% of adolescents identify as transgender and many more seek care, yet the impact of gender-affirming hormone therapy (GAHT) on cardiometabolic health is unknown.

OBJECTIVE

To determine insulin sensitivity and body composition among transgender females (TF) and males (TM) on estradiol or testosterone, compared with cisgender females (CF) and males (CM).

DESIGN

Pilot, cross-sectional study conducted from 2016-2018.

SETTING

Academic regional transgender referral center.

PARTICIPANTS

Transgender adolescents on either testosterone or estradiol for at least 3 months were recruited. Nineteen TM were matched to 19 CM and 42 CF on pubertal stage and body mass index (BMI). Eleven TF were matched to 23 CF and 13 TF to 24 CM on age and BMI.

MAIN OUTCOME MEASURES

1/[fasting insulin] and body composition (dual-energy x-ray absorptiometry).

RESULTS

Total body fat was lower in TM than CF mean ± SD: (29% ± 7% vs 33% ± 7%; P = 0.002) and higher than in CM (28% ± 7% vs 24% ± 9%; P = 0.047). TM had higher lean mass than CF (68% ± 7% vs 64% ± 7%, P = 0.002) and lower than CM (69% ± 7% vs 73% ± 8%; P = 0.029). Insulin sensitivity was not different between the groups.TF had lower body fat than CF (31% ± 7% vs 35% ± 8%; P = 0.033) and higher than CM (28% ± 6% vs 20% ± 10%; P = 0.001). TF had higher lean mass than CF (66% ± 6% vs 62% ± 7%; P = 0.032) and lower than CM (69% ± 5% vs 77% ± 9%; P = 0.001). TF were more insulin resistant than CM (0.078 ± 0.025 vs 0.142 ± 0.064 mL/μU; P = 0.011).

CONCLUSIONS

Transgender adolescents on GAHT have significant differences in body composition compared with cisgender controls, with a body composition intermediate between BMI-matched CMs and CFs. These changes in body composition may have consequences for the cardiometabolic health of transgender adolescents.

CLINICALTRIALS.GOV

NCT02550431.

The Role of Diet and Weight Loss in Improving Secondary Hypogonadism in Men with Obesity with or without Type 2 Diabetes Mellitus

Despite growing recognition of the issue, obesity represents one of the most common public health problems, and its rates are still increasing globally. Among the number of comorbidities and complications associated with obesity, hypogonadism is listed, and this disorder, although frequently neglected, is characterized by a relevant impact on both quality of life and life expectancy. It is generally accepted that hypogonadism secondary to obesity is functional since it is reversible following weight loss. This review summarizes all current research examining the bidirectional relationship between excess body weight and low testosterone levels. Specifically, it evaluates the role that diet, with or without physical activity, plays in improving body weight and hypogonadism in adult and elderly men with obesity, with or without type 2 diabetes mellitus.

Sex hormone-binding globulin and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS), one of the most common endocrine diseases that causes infertility in reproductive women, is characterized by hyperandrogenemia, chronic anovulation, and polycystic ovary morphology (PCOM), and most women with PCOS have metabolic abnormalities. A reduction in plasma sex hormone-binding globulin (SHBG), a transport carrier that binds estrogen and androgens and regulates their biological activities, is often used as an indicator of hyperandrogenism in women with PCOS. Low serum SHBG levels are considered a biomarker of abnormal metabolism and are related to insulin resistance (IR), compensatory hyperinsulinemia and abnormalities in glucose and lipid metabolism in PCOS patients. SHBG is also associated with the long-term prognosis of PCOS. SHBG gene polymorphism is correlated with the risk of PCOS. As SHBG plays a vital role in the occurrence and development of PCOS, knowledge regarding its role in PCOS is helpful for further understanding the molecular mechanism of SHBG in PCOS development and providing new ideas for the treatment of female infertility. Hepatocyte nuclear factor-4α (HNF-4α) is a vital transcription factor in the SHBG synthesis process. HNF-4α binds to the cis-type element DR1 in the SHBG promoter to initiate transcription and regulates hepatic SHBG levels by modulating glucose and lipid metabolism and inflammatory factors. However, it remains unclear whether HNF-4α is indirectly involved in the pathogenesis of PCOS via regulation of hepatic SHBG synthesis. Therefore, this review discusses the interaction between SHBG and the various complications of PCOS as well as the regulatory effect of HNF-4α on SHBG expression.