Prepubertal girls with premature adrenarche have greater bone mineral content and density than controls

Hormonal Control of Bone Architecture Throughout the Lifespan: Implications for Fracture Prediction and Prevention

BACKGROUND

Skeletal modeling in childhood and adolescence and continuous remodeling throughout the lifespan are designed to adapt to a changing environment and resist external forces and fractures. The flux of sex steroids in men and women, beginning from fetal development and evolving through infancy, childhood, puberty, young adulthood, peri/menopause transition, and postmenopause, is critical for bone size, peak bone mass, and fracture resistance.

OBJECTIVE

This review will highlight how changes in sex steroids throughout the lifespan affect bone cells and the consequence of these changes on bone architecture and strength.

METHODS

Literature review and discussion.

RESULTS

The contributions of estrogen and testosterone on skeletal development have been difficult to study due to the reciprocal and intertwining contributions of one on the other. Although orchiectomy in men renders circulating testosterone absent, circulating estrogen also declines due to testosterone being the substrate for estradiol. The discovery of men with absent estradiol or resistance to estrogen and the study of mouse models led to the understanding that estrogen has a larger direct role in skeletal development and maintenance in men and women. The mechanistic reason for larger bone size in men is incompletely understood but related to indirect effects of testosterone on the skeleton, such as higher muscle mass leading to larger mechanical loading. Declines in sex steroids during menopause in women and androgen deprivation therapies in men have profound and negative effects on the skeleton. Therapies to prevent such bone loss are available, but how such therapies can be tailored based on bone size and architecture remains an area of investigation.

CONCLUSION

In this review, the elegant interplay and contribution of sex steroids on bone architecture in men and women throughout the lifespan is described.

Update on Adrenarche-Still a Mystery

CONTEXT

Adrenarche marks the timepoint of human adrenal development when the cortex starts secreting androgens in increasing amounts, in healthy children at age 8-9 years, with premature adrenarche (PA) earlier. Because the molecular regulation and significance of adrenarche are unknown, this prepubertal event is characterized descriptively, and PA is a diagnosis by exclusion with unclear long-term consequences.

EVIDENCE ACQUISITION

We searched the literature of the past 5 years, including original articles, reviews, and meta-analyses from PubMed, ScienceDirect, Web of Science, Embase, and Scopus, using search terms adrenarche, pubarche, DHEAS, steroidogenesis, adrenal, and zona reticularis.

EVIDENCE SYNTHESIS

Numerous studies addressed different topics of adrenarche and PA. Although basic studies on human adrenal development, zonation, and zona reticularis function enhanced our knowledge, the exact mechanism leading to adrenarche remains unsolved. Many regulators seem involved. A promising marker of adrenarche (11-ketotestosterone) was found in the 11-oxy androgen pathway. By current definition, the prevalence of PA can be as high as 9% to 23% in girls and 2% to 10% in boys, but only a subset of these children might face related adverse health outcomes.

CONCLUSION

New criteria for defining adrenarche and PA are needed to identify children at risk for later disease and to spare children with a normal variation. Further research is therefore required to understand adrenarche. Prospective, long-term studies should characterize prenatal or early postnatal developmental pathways that modulate trajectories of birth size, early postnatal growth, childhood overweight/obesity, adrenarche and puberty onset, and lead to abnormal sexual maturation, fertility, and other adverse outcomes.

Etiological, Clinical and Biochemical Characteristics of 367 Children with Early Pubertal Development from Thrace Region of Turkey

Background: Appearance of menarche before nine years of age, secondary sex characteristics before 8 in girls and 9 in boys is defined as Precocious Puberty (PP). Objective: The aim of this study was to describe etiologies, clinical findings, and compare anthropometric properties and biochemical characteristics of children with PP. Methods: In this single-centre study, 367 patients of whom medical records were reviewed diagnosed as premature thelarche (PT), premature adrenarche (PA), Central PP (CPP), and peripheral PP (PPP). The diagnosis was based on clinical, laboratory, and radiologic investigations and their follow-up. Results: During six years, 349 girls (%95,1) and 18 boys (%4,9) diagnosed as PP. The most common etiologies were CPP;127 (%34,6), PT;117 (%31,9), PA;112(%30,5) and PPP 11(%3), respectively. CPP group had significantly higher levels of height, weight, body mass index (BMI) and obesity/overweight incidence, estradiol (E2), basal luteinizing hormone (LH), peak LH, and peak LH/ follicle-stimulating hormone (FSH) ratio and higher uterine dimensions compared to the PT group while the PT group had significantly higher levels of peak FSH compared to the CPP group (p

Association between dehydroepiandrosterone sulphate levels at 7 years old and bone mineral density at 10 years old: a prospective cohort study

We aimed to explore the effect of dehydroepiandrosterone sulphate (DHEAS) at age 7 on areal bone mineral density (aBMD) at age 10 and to distinguish the direct and indirect effects (explained by sexual maturity and by aBMD at age 7), for each sex, after adjustment for body mass index (BMI) z-score. In a subsample of 274 children (139 girls, 135 boys) from Generation XXI cohort, aBMD was assessed with dual-energy X-ray absorptiometry (DXA) scan at ages 7 and 10. The increase in aBMD at age 10 for each 10 µg/dL increase in DHEAS levels at age 7 was estimated using path analysis. Both the direct and the indirect effects were calculated. In girls, higher DHEAS levels at age 7 were associated with higher aBMD at age 10. No direct effect was observed. The indirect effect via higher aBMD at age 7 explained 61% of the total effect, and the indirect effect via higher Tanner stage explained 21%. After adjustment for BMI, the total effect remained statistically significant, explained in 33% by the indirect effect of DHEAS on Tanner stage and Tanner stage on aBMD. In boys, no effect of DHEAS on aBMD was observed.

CONCLUSION

An indirect effect of DHEAS at age 7 on aBMD at age 10 was found in girls, but not in boys, as higher DHEAS levels were associated with more advanced sexual maturation at age 10, and more advanced sexual maturation to higher aBMD. No direct effect of DHEAS on aBMD was observed.

WHAT IS KNOWN

• Conditions associated with elevated DHEAS, adrenarche's biomarker, are accompanied by advanced bone maturity. • Whether adrenal androgens influence bone mineralization in childhood remains puzzling, and longitudinal data is scarce.

WHAT IS NEW

• In girls, but not in boys, higher DHEAS at age 7 was associated with higher aBMD at age 10. • This was partially explained by the indirect effect of DHEAS at age 7 on sexual maturity at age 10, as DHEAS at age 7 was positively associated with sexual maturity at age 10, which was further associated with aBMD.

Normal and Premature Adrenarche

Adrenarche is the maturational increase in adrenal androgen production that normally begins in early childhood. It results from changes in the secretory response to adrenocorticotropin (ACTH) that are best indexed by dehydroepiandrosterone sulfate (DHEAS) rise. These changes are related to the development of the zona reticularis (ZR) and its unique gene/enzyme expression pattern of low 3ß-hydroxysteroid dehydrogenase type 2 with high cytochrome b5A, sulfotransferase 2A1, and 17ß-hydroxysteroid dehydrogenase type 5. Recently 11-ketotestosterone was identified as an important bioactive adrenarchal androgen. Birth weight, body growth, obesity, and prolactin are related to ZR development. Adrenarchal androgens normally contribute to the onset of sexual pubic hair (pubarche) and sebaceous and apocrine gland development. Premature adrenarche causes ≥90% of premature pubarche (PP). Its cause is unknown. Affected children have a significantly increased growth rate with proportionate bone age advancement that typically does not compromise growth potential. Serum DHEAS and testosterone levels increase to levels normal for early female puberty. It is associated with mildly increased risks for obesity, insulin resistance, and possibly mood disorder and polycystic ovary syndrome. Between 5% and 10% of PP is due to virilizing disorders, which are usually characterized by more rapid advancement of pubarche and compromise of adult height potential than premature adrenarche. Most cases are due to nonclassic congenital adrenal hyperplasia. Algorithms are presented for the differential diagnosis of PP. This review highlights recent advances in molecular genetic and developmental biologic understanding of ZR development and insights into adrenarche emanating from mass spectrometric steroid assays.

Osteoblasts Generate Testosterone From DHEA and Activate Androgen Signaling in Prostate Cancer Cells

Bone metastasis is a complication of prostate cancer in up to 90% of men afflicted with advanced disease. Therapies that reduce androgen exposure remain at the forefront of treatment. However, most prostate cancers transition to a state whereby reducing testicular androgen action becomes ineffective. A common mechanism of this transition is intratumoral production of testosterone (T) using the adrenal androgen precursor dehydroepiandrosterone (DHEA) through enzymatic conversion by 3β- and 17β-hydroxysteroid dehydrogenases (3βHSD and 17βHSD). Given the ability of prostate cancer to form blastic metastases in bone, we hypothesized that osteoblasts might be a source of androgen synthesis. RNA expression analyses of murine osteoblasts and human bone confirmed that at least one 3βHSD and 17βHSD enzyme isoform was expressed, suggesting that osteoblasts are capable of generating androgens from adrenal DHEA. Murine osteoblasts were treated with 100 nM and 1 μM DHEA or vehicle control. Conditioned media from these osteoblasts were assayed for intermediate and active androgens by liquid chromatography-tandem mass spectrometry. As DHEA was consumed, the androgen intermediates androstenediol and androstenedione were generated and subsequently converted to T. Conditioned media of DHEA-treated osteoblasts increased androgen receptor (AR) signaling, prostate-specific antigen (PSA) production, and cell numbers of the androgen-sensitive prostate cancer cell lines C4-2B and LNCaP. DHEA did not induce AR signaling in osteoblasts despite AR expression in this cell type. We describe an unreported function of osteoblasts as a source of T that is especially relevant during androgen-responsive metastatic prostate cancer invasion into bone. © 2021 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Interpretation of androgen and anti-Mullerian hormone profiles in a Hispanic cohort of 5- to 8-year-old girls with premature adrenarche

PURPOSE

Premature adrenarche (PA) often leads to polycystic ovary syndrome (PCOS). Higher anti-mullerian hormone (AMH) levels are reported in PCOS. We studied the androgen profile and AMH profiles in Hispanic girls with PA (aged 5-8 years) and age and body mass index (BMI) matched controls.

METHODS

Retrospective review of electronic medical records of girls who met the inclusion criteria for premature adrenarche were done.

RESULTS

PA girls (n=76) were matched to control girls (n=12) for age (mean±standard deviation) (6.7±1 years vs. 6.2±1.3 years) and BMI (20±10 kg/m2 vs. 17.8±2.7 kg/m2). Dehydroepiandrostenedione sulfate (63.3±51.3 μg/dL vs. 29.8±17.3 μg/dL, P<0.001) and testosterone levels (11.4±4.8 ng/dL vs. 8.2±2.9 ng/dL, P=0.001) were significantly higher in the PA group than controls. AMH values (<14 years: reference range, 0.49-3.15 ng/mL) were 3.2±2.2 ng/mL vs. 4.6± 3.2 ng/mL respectively in the PA and control groups and were not different (P=0.4). AMH did not show a correlation with bone age (P=0.1), and testosterone (P=0.9) in the PA group. 17-hydroxyprogesterone levels (17-OHP ng/dL) were 39.5±30.5 ng/dL vs. 36.8±19.8 ng/dL in PA versus control girls. The concentration of 17-OHP was not statistically different between the control and PA groups.

CONCLUSION

Higher AMH was not observed in PA girls and no correlation with BA and androgen levels was observed.

Cortical bone mineral density in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

BACKGROUND

Prior studies reveal that bone mineral density (BMD) in congenital adrenal hyperplasia (CAH) is mostly in the osteopaenic range and is associated with lifetime glucocorticoid dose. The forearm, a measure of cortical bone density, has not been evaluated.

OBJECTIVE

We aimed to evaluate BMD at various sites, including the forearm, and the factors associated with low BMD in CAH patients.

METHODS

Eighty CAH adults (47 classic, 33 nonclassic) underwent dual-energy-x-ray absorptiometry and laboratory and clinical evaluation. BMD Z-scores at the AP spine, total hip, femoral neck, forearm and whole body were examined in relation to phenotype, body mass index, current glucocorticoid dose, average 5-year glucocorticoid dose, vitamin D, 17-hydroxyprogesterone, androstenedione, testosterone, dehydroepiandrosterone and dehydroepiandrosterone sulphate (DHEAS).

RESULTS

Reduced BMD (T-score <-1 at hip, spine, or forearm) was present in 52% and was more common in classic than nonclassic patients (P = 0·005), with the greatest difference observed at the forearm (P = 0·01). Patients with classic compared to nonclassic CAH, had higher 17-hydroxyprogesterone (P = 0·005), lower DHEAS (P = 0·0002) and higher non-traumatic fracture rate (P = 0·0005). In a multivariate analysis after adjusting for age, gender, height standard deviation, phenotype and cumulative glucocorticoid exposure, higher DHEAS was independently associated with higher BMD at the spine, radius and whole body.

CONCLUSION

Classic CAH patients have lower BMD than nonclassic patients, with the most affected area being the forearm. This first study of forearm BMD in CAH patients suggests that low DHEAS may be associated with weak cortical bone independent of glucocorticoid exposure.

Premature adrenarche: etiology, clinical findings, and consequences

Adrenarche means the morphological and functional change of the adrenal cortex leading to increasing production of adrenal androgen precursors (AAPs) in mid childhood, typically at around 5-8 years of age in humans. The AAPs dehydroepiandrosterone (DHEA) and its sulfate conjugate (DHEAS) are the best serum markers of adrenal androgen (AA) secretion and adrenarche. Normal ACTH secretion and action are needed for adrenarche, but additional inherent and exogenous factors regulate AA secretion. Inter-individual variation in the timing of adrenarche and serum concentrations of DHEA(S) in adolescence and adulthood are remarkable. Premature adrenarche (PA) is defined as the appearance of clinical signs of androgen action (pubic/axillary hair, adult type body odor, oily skin or hair, comedones, acne, accelerated statural growth) before the age of 8 years in girls or 9 years in boys associated with AAP concentrations high for the prepubertal chronological age. To accept the diagnosis of PA, central puberty, adrenocortical and gonadal sex hormone secreting tumors, congenital adrenal hyperplasia, and exogenous source of androgens need to be excluded. The individually variable peripheral conversion of circulating AAPs to biologically more active androgens (testosterone, dihydrotestosterone) and the androgen receptor activity in the target tissues are as important as the circulating AAP concentrations as determinants of androgen action. PA has gained much attention during the last decades, as it has been associated with small birth size, the metabolic and polycystic ovarian syndrome (PCOS), and thus with an increased risk for type 2 diabetes and cardiovascular diseases in later life. The aim of this review is to describe the known hormonal changes and their possible regulators in on-time and premature adrenarche, and the clinical features and possible later health problems associating with PA.

The Relationship of Metabolic Syndrome and Body Composition in Children with Premature Adrenarche: Is It Age Related?

BACKGROUND

Studies that evaluate both body composition and metabolic syndrome (MeS) risk in prepubertal children with premature adrenarche (PA) are limited.

METHODS

Fifty-eight prepubertal children (aged 5-9 years, 33 female and 25 male), 30 with PA and 28 controls, were evaluated for the presence of MeS as defined by age-modified National Cholesterol Education Program Adult Treatment Panel III criteria. A subset had dual-energy X-ray absorptiometry and bone markers (n = 23/58) to evaluate the effect of hyperandrogenism on metabolic abnormalities and body composition.

RESULTS

There was no difference in the prevalence of MeS between PA and controls (p = 0.138). Children with MeS were obese with an increased waist circumference (WC) and decreased high-density lipoprotein levels. Androgens were not associated with having more than one criterion for MeS (p = 0.08) but were associated with triglycerides and WC (p = 0.029 and p = 0.041, respectively). Lean mass was greater in PA subjects (p = 0.039), and androgens correlated with bone mineral density (p = 0.029) and total body fat (p = 0.008). Subjects with a higher percent of body fat were more likely to have more than one MeS risk factor (p = 0.005).

CONCLUSIONS

MeS was seen only in obese subjects whether or not they had PA. Thus, it appears that obesity drives metabolic risk in the prepubertal population rather than PA. Our findings are important in determining how the prepubertal patient with PA should be evaluated for metabolic risk.

Relation of adrenal-derived steroids with bone maturation, mineral density and geometry in healthy prepubertal and early pubertal boys

BACKGROUND

Little is known about the effects of adrenal steroids on skeletal maturation and bone mass acquisition in healthy prepubertal boys.

OBJECTIVE

To study whether adrenal-derived steroids within the physiological range are associated with skeletal maturation, areal and volumetric bone mineral density (aBMD and vBMD) and bone geometry in healthy prepubertal and early pubertal boys.

METHODS

98 healthy prepubertal and early pubertal boys (aged 6-14 y) were studied cross-sectionally. Androstenedione (A) and estrone (E1) were determined by liquid chromatography tandem mass spectrometry and DHEAS was determined by immunoassay. Whole body and lumbar spine aBMD and bone area were determined by dual-energy X-ray absorptiometry. Trabecular (distal site) and cortical (proximal site) vBMD and bone geometry were assessed at the non-dominant forearm and leg using peripheral QCT. Skeletal age was determined by X-ray of the left hand.

RESULTS

Adrenal-derived steroids (DHEAS, A and E1) are positively associated with bone age in prepubertal and early pubertal children, independently of age. There are no associations between the adrenal-derived steroids and the studied parameters of bone size (lumbar spine and whole body bone area, trabecular or cortical area at the radius or tibia, periosteal circumference and cortical thickness at the radius or tibia) or BMD (aBMD or vBMD).

CONCLUSION

In healthy prepubertal and early pubertal boys, serum adrenal-derived steroid levels, are associated with skeletal maturation, independently of age, but not with bone size or (v)BMD. Our data suggest that adrenal derived steroids are not implicated in the accretion of bone mass before puberty in boys.

Risky, early, controversial. Puberty in medical discourses

This article comes within the compass of a research program (entitled CorAge. Bodily Experiences and AgePassages among 9-13 year-olds (ANR-09-ENFT-017) conducted between 2009 and 2013 about the emergence of a "new" age in life--"preadolescence"--as instanced in France (Alsace, Lorraine) and Italy (Venetia). The impressive amount of references to "early puberty" and "precocious puberty", in a context of feeling of a premature end of childhood, led us to make an in-depth study of this issue: first, through an analysis of international and French and Italian medical journals; second, through interviews with health professionals. Following the thesis of Foucault, we assume that the discourses on puberty timing participate of classifications of the child body drenched with moral representations of childhood, especially on gender and age issue. Our results: the question of whether a secular trend in puberty timing even exists continues to be debated between American and European scientists. Second, the terms "puberty", "precocious puberty", "early puberty" have been used to indicate a variety of puberty markers, increasing confusion. A controversy has focused on early breast development in girls, because this attribute is questioning the order of ages and gender. Moreover, psychosocial factors presented as accelerating early puberty, do not demonstrate the relation between earliness and risk behavior. The literature, as it is moved by the female precocity, creates a medical category to objectify the complex and flexible process of puberty and invent female child precocity. These differences between American and European scholars and the interviews with French and Italian health professional show a gap between the international literature and practitioners, clinicians and nurses who regularly work with children: they neither find pubertal advancement, nor increase of "true precocious puberty", although they share concerns about premature feminization of girls (France) or environmental toxicity (Italy) on children.

Approach to the girl with early onset of pubic hair

Premature pubarche, or the development of pubic hair before the age of 8 in girls or 9 in boys, is most commonly caused by premature adrenarche. Adrenarche is the maturation of the adrenal zona reticularis in both boys and girls, resulting in the development of pubic hair, axillary hair, and adult apocrine body odor. Although originally thought to be a benign variant of normal development, premature adrenarche has been associated with insulin resistance and the later development of metabolic syndrome and polycystic ovary syndrome. Although further studies are needed to confirm these relationships, the case presented herein argues for periodic assessment of children at risk. Indeed, recognition of these associations may allow for early preventive measures.

Bone age advancement in prepubertal children with obesity and premature adrenarche: possible potentiating factors

Obesity and premature adrenarche (PA) are both associated with bone age (BA) advancement of unclear etiology, which may lead to earlier puberty, suboptimal final height and obesity in adulthood. Our objective was to understand the hormonal and anthropometric characteristics of BA advancement in a spectrum of prepubertal children with and without obesity and PA. In this cross-sectional study of 66 prepubertal children (35 PA, 31 control, 5-9 years), BMI z-score, hormonal values and response to an oral glucose tolerance test were the main outcome measures. Subjects were divided into tertiles by BA divided by chronological age (BA/CA), an index of BA advancement. Subjects in the top tertile for BA/CA had the highest dehydroepiandrosterone sulfate (DHEAS), free testosterone (%), hemoglobin A(1C), BMI z-score, and weight (P < 0.05). BMI z-score (r = 0.47), weight (r = 0.40), free testosterone (%) (r = 0.34), and DHEAS (r = 0.30) correlated with BA/CA (P < 0.02). Regression analysis showed greater BA/CA in PA compared to controls after controlling for weight (0.21 ± 0.56, P < 0.004). An exploratory stepwise regression model showed that weight, estradiol, and DHEAS were the strongest predictors of BA/CA accounting for 24% of its variance. Obesity was highly associated with BA advancement in this study of prepubertal children. In addition, children with PA had greater BA/CA at any given weight when compared to controls. These findings suggest a possible hormonal factor, which potentiates the effect of obesity on BA advancement in children with obesity and/or PA.

Body composition and bone mineral density in children with premature adrenarche and the association of LRP5 gene polymorphisms with bone mineral density

CONTEXT

Precocious increase in adrenal androgen production is the hallmark of premature adrenarche (PA). Adrenal androgens have anabolic properties.

OBJECTIVE

The objective of the study was to test whether body composition and bone mineral density (BMD) are altered in PA and study whether genetic variation in low-density lipoprotein receptor-related protein 5 (LRP5) affects BMD in PA.

DESIGN

This was a cross-sectional study.

SETTING

The study was conducted at a university hospital.

SUBJECTS AND MEASURES

The study included 126 prepubertal children (64 with PA, 10 boys; 62 non-PA controls, 10 boys). Femoral neck and lumbar spine areal and calculated volumetric BMD (dual energy X-ray absorptiometry), body composition (bioimpedance), serum 25-hydroxyvitamin D, and markers of bone turnover and calcium homeostasis were compared between the PA and control groups. Single-nucleotide polymorphisms of LRP5 were determined and associated with BMD.

RESULTS

Children with PA had higher femoral neck and lumbar spine BMD(areal) than the controls (Z-score 0.56 vs. -0.09, P < 0.001, and 0.20 vs. -0.31, P = 0.009, respectively). However, the mean BMDs did not differ significantly between the groups when adjusted for height or bone size. BMD(areal) correlated strongly with height sd score in both groups. Among the PA children, LRP5 single-nucleotide polymorphism E644E minor variant was associated with lower and F549F minor variant with higher BMD. Total body fat mass, fat percent, serum PTH, and alkaline phosphatase concentrations were higher and 25-hydroxyvitamin D lower in the PA group.

CONCLUSIONS

Prepubertal children with PA had higher BMD(areal) compared with healthy controls. This was mainly explained by their increased height. LRP5 polymorphisms may contribute to bone mass accrual in prepubertal PA children.

Adrenal function during childhood and puberty in daughters of women with polycystic ovary syndrome

CONTEXT

In some patients, PCOS may develop as a consequence of an exaggerated adrenarche during pubertal development.

OBJECTIVE

The aim of the study was to assess adrenal function during childhood and pubertal development in daughters of women with PCOS (PCOSd).

DESIGN

We included 98 PCOSd [64 during childhood (ages 4-8 yr) and 34 during the peripubertal period (ages 9-13 yr)] and 51 daughters of control women (Cd) [30 during childhood and 21 during the peripubertal period]. In both groups, an acute ACTH-(1-24) stimulation test (0.25 mg) and an oral glucose tolerance test were performed. Bone age and serum concentrations of cortisol, androstenedione, 17-hydroxyprogesterone, dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), glucose, and insulin were determined.

RESULTS

PCOSd and Cd were similar in age and body mass index. During the peripubertal period, basal and poststimulated DHEAS concentrations were higher in PCOSd compared to Cd. Among PCOSd, 12.5% of girls in childhood and 32.4% in peripuberty presented biochemical evidence of exaggerated adrenarche. Stimulated insulin was higher in PCOSd compared to Cd during childhood (P = 0.03) and peripuberty (P = 0.03). An advancement of 8 months between bone and chronological age was observed in peripubertal PCOSd compared to Cd.

CONCLUSIONS

In PCOSd, basal and stimulated DHEAS concentrations were higher during the onset of puberty. Around 30% of the PCOSd demonstrated an exacerbated adrenarche, which may reflect increased P450c17 activity. In addition, a modest advance in bone age was observed, probably secondary to the hyperinsulinemia and/or adrenal hyperandrogenism.

Body composition in premature adrenarche by structural MRI, 1H MRS and DXA

BACKGROUND

Premature adrenarche (PA) is recognized to be a possible precursor of polycystic ovarian syndrome, type 2 diabetes mellitus and cardiovascular disease. Visceral adiposity and increased intramyocellular lipid (IMCL) are associated with insulin resistance and increased risk of cardiovascular disease.

AIM

To determine whether prepubertal girls with PA have altered visceral adiposity and/or increased muscle lipid content compared to prepubertal girls without PA using proton magnetic resonance imaging (MRI) and spectroscopy (1H MRS).

PATIENTS AND METHODS

We performed total body dual energy X-ray absorptiometry (DXA) scans, MRI of the trunk, and MRS of the tibialis anterior muscle in the right calf on six girls with PA and eight prepubertal controls.

RESULTS

Amount of visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT), and VAT to SAT ratio did not differ significantly between the PA and control girls. Those with PA, however, had significantly greater IMCL than controls (p = 0.004).

CONCLUSIONS

This study adds further evidence that PA is not a benign condition, and future studies investigating early intervention with dietary and exercise counseling may help diminish potential risk for diabetes mellitus and/or cardiovascular disease.

Clinical spectrum of premature pubarche: links to metabolic syndrome and ovarian hyperandrogenism

Premature pubarche-defined as the appearance of pubic hair before age 8 years in girls and 9 years in boys-has been traditionally considered a benign entity. However, recent evidence supports the notion that premature pubarche in girls may be a forerunner of the metabolic syndrome, and may precede the development of clinical ovarian androgen excess in adolescence. This sequence seems to occur more frequently when premature pubarche was preceded by reduced fetal growth and followed by excessive postnatal catch-up in height and particularly in weight; hyperinsulinemia appears to be a key factor in the development of this sequence of events. In girls with premature pubarche and a history of a low birth weight, puberty tends to start earlier and to have a faster course, so that final height may be moderately reduced. In these girls, metformin therapy may reverse the progression to clinical ovarian hyperandrogenism, normalize body composition and excess visceral fat, and delay pubertal progression without attenuating linear growth and bone mineralization, suggesting that adult height may be improved. Long-term follow-up of these patients is needed to fully determine the ultimate effects of insulin sensitization as well as the maintenance of these benefits after discontinuation of therapy.

Prepubertal healthy children's urinary androstenediol predicts diaphyseal bone strength in late puberty

CONTEXT

During the physiological process of adrenarche, the adrenal glands of healthy children secrete increasing amounts of weak androgenic steroids partly metabolized to potent sex steroids.

OBJECTIVE

The aim of the study was to examine whether adrenal androgen metabolite excretion rates before the onset of puberty may be prospectively associated with late-pubertal diaphyseal bone strength.

SETTING

We conducted the study in an auxological and metabolic child nutrition research facility.

STUDY POPULATION AND DESIGN

The sample included 45 healthy adolescents who underwent proximal forearm bone and muscle area measurements by peripheral quantitative computed tomography at the age of 16 yr (SD 1.5) and who had collected a 24-h urine sample 8 yr earlier, allowing to quantify the prepubertal urine metabolome. Prepubertal hormonal predictors quantified by gas chromatography-mass spectrometry were: dehydroepiandrosterone, its 16-hydroxylated downstream metabolites, 5-androstene-3beta,17beta-diol (androstenediol), sums of total androgen and glucocorticoid metabolites, cortisol, and 6beta-hydroxycortisol.

MAIN OUTCOMES

Proximal forearm radius was measured.

RESULTS

Of all prepubertal hormones analyzed, only sex- and age-specific androstenediol levels significantly predicted pubertal stage-, height-, and muscularity-adjusted diaphyseal bone modeling (periosteal circumference, beta = 0.67, P = 0.002; cortical area, beta = 2.15, P = 0.02), bone mineral content (beta = 2.2; P = 0.04), and polar strength strain index (beta = 12.2; P = 0.002). Androstenediol explained 5-10% of the late-pubertal diaphyseal radius variability.

CONCLUSIONS

Our prospective profiling of urinary steroid metabolites in 24-h urine samples collected before puberty suggests that androstenediol is an early predictor of the diaphyseal bone strength in late puberty. This predominantly peripheral conversion product of adrenarchal dehydroepiandrosterone by 17beta-hydroxysteroid dehydrogenase may hence be involved in a sustained improvement of radial bone accretion during growth.

Public health implications of altered puberty timing

Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated with an increased risk for testicular cancer according to several, but not all, epidemiologic studies. Girls and, possibly, boys who exhibit premature adrenarche are at a higher risk for developing features of metabolic syndrome, including obesity, type 2 diabetes, and cardiovascular disease later in adulthood. Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment for chemicals. Recent US legislation has mandated improved chemical testing approaches for protecting children's health and screening for endocrine-disrupting agents, which has led to changes in the US Environmental Protection Agency's risk assessment and toxicity testing guidelines to include puberty-related assessments and to the validation of pubertal male and female rat assays for endocrine screening.

Effects of testosterone on cancellous bone, marrow adipocytes, and ovarian phenotype in a young female rat model of polycystic ovary syndrome

OBJECTIVE

To investigate the effects of testosterone on cancellous bone and marrow adipocytes in a young female rat model of polycystic ovary syndrome (PCOS).

DESIGN

Comparative and controlled study.

SETTING

University animal research laboratory.

PATIENT(S)

Fifty-one Sprague-Dawley rats.

INTERVENTION(S)

The rats were divided into four groups based on the day of testosterone propionate (0.1 mg/weight (g)) injection: no testosterone treatment (control group, C); injected on the ninth day after birth (9D); injected 4 weeks after birth (4W); and injected 8 weeks after birth (8W). About 16 weeks after birth, all animals were killed.

MAIN OUTCOME MEASURE(S)

Bone mineral density (BMD) and bone and fat histomorphometry for the proximal tibia and serum hormonal parameters were measured.

RESULT(S)

The ovaries of group 9D showed many cystic follicles without corpora lutea. The BMD of group 9D (0.309 +/- 0.023 g/cm2) was significantly higher than the other groups groups (CONT, 0.262 +/- 0.017; 4W, 0.256 +/- 0.017; 8W, 0.256 +/- 0.022 g/cm2; P < .0001). Based on bone histomorphometry, group 9D had a higher bone volume (BV/TV), lower bone formation (OV/BV, OS/BS, sLS/BS, MAR, BFR/BS), lower bone resorption (ES/BS, Oc.S/BS), and lower rate of longitudinal growth compared to the other groups. Based on fat histomorphometry, group 9D had a lower bone fat volume and number of fat cells in the bone marrow compared to the other groups. On the other hand, groups 4W and 8W showed similar values of bone and fat histomorphometric parameters to group C.

CONCLUSION(S)

Female rats receiving testosterone within nine days of birth develop polycystic ovaries, high bone volume, low bone turnover, and lower fat content in the bone marrow.

Adrenarche and bone modeling and remodeling at the proximal radius: weak androgens make stronger cortical bone in healthy children

Adrenarche, the physiological increase in adrenal androgen secretion, may contribute to better bone status. Proximal radial bone and 24-h urinary steroid hormones were analyzed cross-sectionally in 205 healthy children and adolescents. Positive adrenarchal effects on radial diaphyseal bone were observed. Obviously, adrenarche is one determinant of bone mineral status in children.

INTRODUCTION

Increased bone mass has been reported in several conditions with supraphysiological adrenal androgen secretion during growth. However, no data are available for normal children. Therefore, our aim was to examine whether adrenal androgens within their physiological ranges may be involved in the strengthening of diaphyseal bone during growth.

METHODS

Periosteal circumference (PC), cortical density, cortical area, bone mineral content, bone strength strain index (SSI), and forearm cross-sectional muscle area were determined with peripheral quantitative computed tomography (pQCT) at the proximal radial diaphysis in healthy children and adolescents. All subjects, aged 6-18 years, who collected a 24-h urine sample around the time of their pQCT analysis (100 boys, 105 girls), were included in the present study, and major urinary glucocorticoid (C21) and androgen (C19) metabolites were quantified using gas chromatography-mass spectrometry.

RESULTS AND CONCLUSIONS

We found a significant influence of muscularity, but not of hormones, on periosteal modeling (PC) before the appearance of pubic hair (prepubarche). Similarly, no influence of total cortisol secretion (C21) was seen on the other bone variables. However, positive effects of C19 on cortical density (p < 0.01), cortical area (p < 0.001), bone mineral content (p < 0.001), and SSI (p < 0.001)--reflecting, at least in part, reduction in intracortical remodeling-were observed in prepubarchal children after muscularity or age had been adjusted for. This early adrenarchal contribution to proximal radial diaphyseal bone strength was further confirmed for all cortical variables (except PC) when, instead of C19 and C21, specific dehydroepiandrosterone metabolites were included as independent variables in the multiple regression model. During development of pubic hair (pubarche), muscularity and pubertal stage rather than adrenarchal hormones seemed to influence bone variables. Our study shows that especially the prepubarchal increase in adrenal androgen secretion plays an independent role in the accretion of proximal radial diaphyseal bone strength in healthy children.