Candidate gene analysis in premature pubarche and adolescent hyperandrogenism

Childhood Obesity: An Updated Review

BACKGROUND

Childhood obesity is an important and serious public health problem worldwide.

OBJECTIVE

This article aims to familiarize physicians with the evaluation, management, and prevention of childhood.

METHODS

A PubMed search was conducted in May, 2021, in Clinical Queries using the key terms "obesity" OR "obese". The search included clinical trials, randomized controlled trials, case-control studies, cohort studies, meta-analyses, observational studies, clinical guidelines, case reports, case series, and reviews. The search was restricted to English literature and children. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Most obese children have exogenous obesity characterized by a growth rate for height above the 50th percentile, normal intelligence, normal genitalia, and lack of historical or physical evidence of an endocrine abnormality or a congenital syndrome. Obese children are at risk for dyslipidemia, hypertension, diabetes mellitus, non-alcoholic fatty liver disease, obstructive sleep apnea, psychosocial disturbances, impaired quality of life, and shorter life expectancy. The multitude of serious comorbidities necessitates effective treatment modalities. Dietary modification, therapeutic exercise, and behavioral modification are the fundamentals of treatment. Pharmacotherapy and/or bariatric surgery should be considered for obese individuals who do not respond to the above measures and suffer from a serious comorbid condition.

CONCLUSION

Childhood obesity, once established, is often refractory to treatment. Most treatment programs lead to a brief period of weight loss, followed by rapid re-accumulation of the lost weight after the termination of therapy. As such, preventive activity is the key to solving the problem of childhood obesity. Childhood obesity can be prevented by promoting a healthy diet, regular physical activity, and lifestyle modification. Parents should be encouraged to get involved in school and community programs that improve their children's nutritional status and physical activity.

Serum 21-Deoxycortisol for Diagnosis of Nonclassic Congenital Adrenal Hyperplasia in Women With Androgen Excess

CONTEXT

Nonclassic congenital adrenal hyperplasia (NCCAH) requires exclusion before diagnosing polycystic ovary syndrome (PCOS). Increasing use of liquid chromatography and tandem mass spectrometry (LC-MS/MS) necessitates revision of immunoassay-based criteria for NCCAH. Measurement of 21-deoxycortisol (21DF) may simplify the diagnosis of heterozygosity (HTZ), the presence of 1 affected CYP21A2 allele, which currently relies on complex molecular studies.

OBJECTIVE

We aimed to determine LC-MS/MS-specific criteria for NCCAH and HTZ and compare the diagnostic accuracy of 21DF and 17-hydroxyprogesterone (17OHP).

METHODS

A cross-sectional study involving 99 hyperandrogenic females was performed. We identified females who had undergone both a synacthen stimulation test (SST) and CYP21A2 genotyping from 2010 to 2017, and prospectively recruited females referred for an SST to investigate hyperandrogenic symptoms from 2017 to 2021. Steroids were compared between genetically confirmed NCCAH, HTZ, and PCOS. Optimal 17OHP and 21DF thresholds for HTZ and NCCAH were determined by receiver operating characteristic analysis.

RESULTS

Basal 17OHP, stimulated 17OHP, and 21DF were measured in 99, 85, and 42 participants, respectively. Optimal thresholds for NCCAH were 3.0 nmol/L and 20.7 nmol/L for basal and stimulated 17OHP, respectively. Basal and stimulated 21DF thresholds of 0.31 nmol/L and 13.3 nmol/L provided 100% sensitivity with specificities of 96.8% and 100% for NCCAH, respectively. Diagnostic thresholds for HTZ of 8.0 nmol/L, 1.0 nmol/L, and 13.6 for stimulated 17OHP, 21DF, and the ratio (21DF + 17OHP)/cortisol each provided 100% sensitivity with specificities of 80.4%, 90.5%, and 85.0%, respectively.

CONCLUSION

LC-MS/MS-specific 17OHP thresholds for NCCAH are lower than those based on immunoassay. LC-MS/MS-quantified 17OHP and 21DF accurately discriminate HTZ and NCCAH from PCOS.

Differences in hormonal levels between heterozygous CYP21A2 pathogenic variant carriers, non-carriers, and females with non-classic congenital hyperplasia

Objective

CYP21A2 mutation heterozygote carriers seem to have an increased risk of hyperandrogenism. However, the clinical relevance of the heterozygote carrier status and the reliability of hormonal testing in discriminating a carrier from a non-carrier are puzzling questions. We aimed to characterize a population of Portuguese females suspected of having non-classic congenital adrenal hyperplasia (NC-CAH) due to clinical and biochemical criteria and who have undergone CYP21A2 molecular analysis.

Methods

Retrospectively, we have analyzed the clinical records of 131 females (32 girls aged 3-9 and 99 adolescents and premenopausal women aged 13-49) who underwent complete CYP21A2 molecular analysis due to suspicion of NC-CAH. We divided included participants into three groups according to the CYP21A2 molecular analysis: NC-CAH females (46), heterozygous carriers (49), and wild type (36). We then compared clinical signs and symptoms as well as biochemical and molecular data between carriers and NC-CAH individuals and between carriers and wild type females. We measured 17OHP by electrochemiluminescence immunoassay.

Results

Clinical features were similar between groups. Heterozygous carriers presented higher basal and post-cosyntropin 17-hydroxyprogesterone (17OHP) than wild type individuals (p < 0.05) and lower basal and stimulated 17OHP levels than NC-CAH patients (p < 0.05). We discovered a considerable overlap between 17OHP levels among groups. The most common pathogenic variant we identified was p.Val282Leu.

Conclusion

In this population of hyperandrogenic women and children, heterozygous carriers showed higher basal and stimulated 17OHP than non-carriers although normal basal and stimulated 17OHP responses do not exclude heterozygosity for CYP21A2 pathogenic variants. In this study, only the molecular analysis presented good sensitivity in identifying heterozygotes.

Premature adrenarche--a common condition with variable presentation

Adrenarche refers to a maturational increase in the secretion of adrenal androgen precursors, mainly dehydroepiandrosterone (DHEA) and its sulfate (DHEAS). In premature adrenarche (PA), clinical signs of androgen action appear before the age of 8/9 years in girls/boys, concurrently with the circulating DHEA(S) concentrations above the usually low prepubertal level. The most pronounced sign of PA is the appearance of pubic/axillary hair, but also other signs of androgen effect (adult type body odor, acne/comedones, greasy hair, accelerated statural growth) are important to recognize. PA children are often overweight and taller than their peers, and the higher prevalence of PA in girls than in boys is probably explained by higher female adiposity and peripheral DHEA(S) conversion to active androgens. PA diagnosis requires exclusion of other causes of androgen excess: congenital adrenal hyperplasia, androgen-producing tumors, precocious puberty, and exogenous source of androgens. PA has been linked with unfavorable metabolic features including hyperinsulinism, dyslipidemia, and later-appearing ovarian hyperandrogenism. Although this common condition is usually benign, PA children with additional risk factors including obesity should be followed up, with the focus on weight and lifestyle. Long-term follow-up studies are warranted to clarify if the metabolic changes detected in PA children persist until adulthood.

Effect of metformin on sleep disorders in adolescent girls with polycystic ovarian syndrome

OBJECTIVE

Patients with polycystic ovarian syndrome (PCOS) have a high prevalence of sleep disorders. Metformin is an antidiabetic drug that may have a role in treatment of the manifestations of PCOS. The aim of this study was to assess the presence of sleep disorders in adolescent girls with PCOS and to study the effects of using metformin on sleep disorders in these girls.

METHODS

This study was carried out on 90 adolescent girls aging from 12 to 18 years who were divided into 3 equal groups: control untreated group, untreated PCOS group, and PCOS + metformin group. Body weight, height, body mass index, hirsutism score, fasting and postprandial blood glucose, fasting serum insulin, Homeostatic Model Assessment (HOMA) index, sleep disturbances scale, and Epworth sleepiness scale were measured.

RESULTS

Metformin administration resulted in significant decrease in the body weight, body mass index, hirsutism score, fasting and postprandial blood glucose, fasting serum insulin, HOMA index, sleep disturbances scale, and Epworth sleepiness scale compared to the untreated PCOS group.

CONCLUSION

Metformin can reduce the incidence of sleep disorders and excessive daytime sleepiness in adolescent girls with PCOS.

Genetic variants associated with insulin signaling and glucose homeostasis in the pathogenesis of insulin resistance in polycystic ovary syndrome: a systematic review

BACKGROUND

Polycystic ovary syndrome must be recognized as a serious issue due to its implication on long term health regardless of an individual's age. PCOS and insulin resistance are interlinked, as approximately 40 % of women with PCOS are insulin resistant. However, the detailed molecular basis for insulin resistance that is coupled with PCOS remains poorly understood.

OBJECTIVE

To review the published evidence that polymorphisms in genes that are involved in insulin secretion and action are associated with an increased risk of PCOS.

METHODS

We reviewed articles published through November 2012 which concerned polymorphisms of genes related to insulin signaling and glucose homeostasis as well as their associations with PCOS. The articles were identified via Medline searches.

CONCLUSIONS

No consistent evidence emerged of a strong association between the risk of PCOS and any known gene that is related to insulin signaling and glucose homeostasis. Moreover, recent genome-wide association studies are inconsistent in identifying the associations between PCOS and insulin metabolism genes. Many of the studies reviewed were limited by heterogeneity in the PCOS diagnosis and by not have having a sufficient number of study participants. Further studies are warranted to determine predisposing risk factors which could modify environmental factors and thus reduce the risk of PCOS. Large genome-wide association studies devoted solely to PCOS will be necessary to identify new candidate genes and proteins that are involved in PCOS risk.

Association of IRS-1 and IRS-2 genes polymorphisms with polycystic ovary syndrome: a meta-analysis

Insulin resistance (IR) plays an important role in the pathogenesis of polycystic ovary syndrome (PCOS) which is a common disorder in premenopausal women. The association between the single nucleotide polymorphisms (SNPs) of insulin receptor substrate (IRS) gene and PCOS in several populations has been studied, but the results are conflicting. The aim of this study was undertaken to investigate association of IRS-1 and IRS-2 genes polymorphisms with PCOS by conducting a meta-analysis. Literature search was conducted through PubMed and EMBASE databases (up to July 31, 2011). Fifteen articles with 1,358 cases and 1,561 controls were enrolled in the meta-analysis of the association between Gly972Arg variant and PCOS, and five articles with 519 cases and 883 controls were enrolled in the meta-analysis of Gly1057Asp variant. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed and random-effects models. The Q-statistic test was used to assess heterogeneity, and Begg's test and Egger's test were used to evaluate publication bias. Sensitivity analysis was also performed. Our results indicated that A allele of Gly972Arg conferred a significantly increased risk of PCOS compared with G allele (OR = 1.91, 95% CI: 1.36-2.68). However, in Gly1057Asp polymorphism the OR of allele A vs. G is 0.92 (95% CI: 0.72, 1.18). Our meta-analysis suggested that IRS-1 Gly972Arg polymorphism might be considered a significant risk for PCOS. Otherwise, no significant associations were observed in IRS-2 Gly1057Asp polymorphism which needs to be further confirmed by further studies.

Report of the international symposium: polycystic ovary syndrome: first Latin-American consensus

During the last years, numerous consensuses have been held in different countries in order to review the data concerning diagnosis and treatment and their relationship with the ethnic origin, social status and lifestyle of women with Polycystic Ovary Syndrome (PCOS). This study describes the conclusions concerning diagnostic criteria and the appropriate treatment of women with PCOS reached during the International Symposium Polycystic Ovary Syndrome, First Latin-American Consensus held in Buenos Aires, Argentina on 4th and 5th May 2009 to be applied in South American.

Characteristics and prevalence of non-classical congenital adrenal hyperplasia with a V2811 mutation in patients with premature pubarche

We aimed to determine the prevalence and clinical characteristics of non-classical congenital adrenal hyperplasia (NCCAH) with V281L mutation in patients with premature pubarche. An adrenocorticotrophic hormone (ACTH) stimulation test was performed in 14 of the 159 patients with premature pubarche (PP). Patients whose stimulated 17alpha-hydroxyprogesterone (17-OHP) level on the ACTH test was > or =10 ng/mL underwent a mutational analysis of the CYP21 gene. NCCAH was defined in nine (5.7%) patients, all of whom had the V281L mutation. Four of the NCCAH patients were homozygote and four of them were heterozygote. One other patient was compound heterozygote for V281L mutation and the I2 splice mutation. One of the patients with V281L heterozygous mutation developed true precocious puberty and the other one had rapid progressive early puberty and developed polycystic ovary syndrome. ACTH stimulated 17-OHP > or = 10 ng/mL in PP patients is load star to mutation analysis and heterozygote patients should be followed for clinical and biological hyperandrogenism up to completion of the whole 'genome sequence'.

Study of association of IRS-1 and IRS-2 genes polymorphisms with clinical and metabolic features in women with polycystic ovary syndrome. Is there an impact?

OBJECTIVE

Insulin receptor substrate (IRS) proteins are critical to signal transduction in insulin target tissues. The present study was undertaken to determine whether IRS-1 Gly972Arg and IRS-2 Gly1057Asp influence hormonal and metabolic characteristics in Greek patients with polycystic ovary syndrome (PCOS) and controls.

MATERIAL AND METHODS

One hundred and eighty-three women with PCOS and 88 healthy volunteers were enrolled. Venous blood samples were obtained for genetic study and hormonal profile, glucose, and insulin assays, on days 3 to 7 from cycling patients. DNA was extracted by whole blood samples for genotyping and detection of IRS-1 Gly972Arg and IRS-2 Gly1057Asp polymorphisms.

RESULTS

Fifty-six women with PCOS (30.60%), whereas 12 women in the control group (13.64%) carried the IRS-1 polymorphism (p = 0.0026). No statistically significant differences in genotypes or allele frequencies for IRS-2 polymorphism were observed between controls and PCOS women. No significant differences in any clinical or hormonal measures between subjects on the basis of genotype were observed, except the increased levels of fasting glucose that exhibit the carriers of the Asp allele of the IRS-2 polymorphism.

CONCLUSIONS

Only the IRS-1 polymorphism is associated with increased susceptibility to PCOS in a Greek population. These loci should not be considered as major contributors to the hormonal and metabolic phenotype of PCOS.

Premature pubarche in Mediterranean girls: high prevalence of heterozygous CYP21 mutation carriers

AIM

This study investigated the prevalence and consequences of heterozygous CYP21A2 mutations in premature pubarche (PP) girls.

MAIN FINDING

We investigated 36 French Mediterranean girls with isolated PP. We performed synacthen testing with 17OHP and 21-deoxycortisol evaluation, along with molecular analysis of the CYP21A2 gene in girls with abnormal elevation of one of these two adrenal steroids. Three girls (8.3%) had nonclassical adrenal hyperplasia, secondary to compound heterozygosity that associated at least one severe mutation for the three girls. A heterozygous mutation of the CYP21A2 gene was confirmed by molecular biology in eight girls (22%); a deletion of the CYP21A2 gene was found in one of them. Biological hyperandrogenism was found in the prepubertal CYP21A2 mutation carriers, whereas the four heterozygous girls who were followed long enough to have reached pubertal age presented biological and clinical hyperandrogenism.

CONCLUSIONS

We underline the high prevalence of heterozygous CYP21A2 mutations in girls with PP and demonstrate the usefulness of systematic screening by synacthen testing, both to improve their future clinical management and to prevent the transmission of classical adrenal hyperplasia to future offspring. Because of the severe metabolic and cardiovascular consequences of hyperandrogenism, long-term follow-up of these heterozygous patients is mandatory.

Polymorphisms of the insulin receptor and the insulin receptor substrates genes in polycystic ovary syndrome: a Mendelian randomization meta-analysis

Polycystic ovary syndrome (PCOS) is a heterogeneous condition with unknown aetiology which is considered to be the most common endocrine disorder in women of reproductive age. In this work we investigated the association of insulin receptor (IotaNSR) and insulin receptor substrates (IRSs) polymorphisms with the risk of developing PCOS. The meta-analysis of eleven studies (889 cases, 1303 controls) yielded a significant association for IRS-1 Gly972Arg (G972R) polymorphism concerning the GR vs. GG genotype (OR: 1.77, 95% CI: 1.28, 2.45), with no between-studies heterogeneity. Concerning IotaNSR His1058 C/T, the meta-analysis of eight studies (795 cases, 576 controls) found no significant evidence for association with PCOS (OR for the TT+CT vs. CC comparison equal to 1.28 with 95% CI: 0.88, 1.85) and a moderate between studies variability (I(2)=44.6%). No evidence for publication bias was found in these meta-analyses. Following a multivariate Mendelian randomization approach, the overall OR was unaffected but the overall mean difference of fasting insulin levels between carriers of GR and RR genotypes in controls was significant (2.18, 95% CI: 0.36, 4.01). These results suggest that IRS-1 Gly972Arg polymorphism is significantly associated with the risk of developing PCOS and that this association is primarily mediated by increasing the levels of fasting insulin. The particular polymorphism is located in a region nearby two phosphorylation sites that interact physically with INSR and PI 3-kinase and there is enough evidence from the literature suggesting that the Arg972 variant is associated with decreased PI 3-kinase activity and impaired insulin-stimulated signaling.

Genetic variation of FTO and TCF7L2 in premature adrenarche

Premature adrenarche (PA) has been associated with increased body mass index. Our aim was to determine whether the obesity-associated variant at fat mass and obesity gene (FTO) is more frequent in PA subjects. Furthermore, we hypothesized that altered Wnt signaling due to genetic variants at transcription factor 7-like 2 (TCF7L2) could play a role in the polygenic pathogenesis of PA. We genotyped polymorphisms at FTO rs9939609 and at TCF7L2 rs7903146 and rs12255372 in 73 Finnish white prepubertal children with PA and in 97 age- and sex-matched healthy controls. In addition, we investigated the associations of these genetic variations with weight, height, circulating adrenocortical hormone levels, glucose metabolism, lipid profile, and blood pressure. The differences in the minor allele frequencies (MAFs) of rs9939609, rs7903146, and rs12255372 were not statistically significant between the PA and control groups (difference in MAFs [95% confidence interval]: -0.06 [-0.18, 0.05], 0.04 [-0.05, 0.12], and 0.01 [-0.07, 0.10]; P = .3, .4, and .8, respectively). However, the risk allele at TCF7L2 rs7903146 was more frequent in PA subjects than in controls when we restricted the analysis to the subjects with lower weight-for-height than the median of the PA subjects (weight-for-height <108%, corresponding body mass index SD score <0.79; difference in MAFs [95% confidence interval]: 0.12 [-0.001, 0.23]; P = .038). Risk variant at FTO rs9939609 associated with higher weight-for-height in the healthy children (P = .001). In conclusion, the minor variant at FTO rs9939609 seems to play no major role in the increased weight-for-height of PA subjects; but the risk allele at TCF7L2 rs7903146 may have a role in the pathogenesis of PA in lean subjects.

LRP5 in premature adrenarche and in metabolic characteristics of prepubertal children

OBJECTIVE

Premature adrenarche (PA) is associated with unfavourable metabolic characteristics. We hypothesized that genetic variation in low density lipoprotein (LDL) receptor-related protein 5 (LRP5), which is involved in Wnt signalling in the adrenal cortex and in cholesterol metabolism, plays a role in the pathogenesis of PA.

DESIGN AND PATIENTS

We performed a cross-sectional association study in 73 Finnish children with PA and 97 age- and gender-matched healthy controls.

MEASUREMENTS

LRP5 genotypes were determined by direct sequencing. Single-marker associations with clinical-metabolic characteristics, including adrenocortical function, glucose tolerance and lipid profile, were examined with age and gender as covariates.

RESULTS

Nineteen single nucleotide polymorphisms (SNPs) in LRP5 were found in the 170 children. No significant differences in the genotype distributions were observed between the PA and control groups. SNPs A1330V and N740N were associated with higher serum dehydroepiandrosterone sulphate (DHEAS) levels in the control subjects (A/A vs. A/a; mean 0.8 vs. 1.4 micromol/l, P = 0.01). They were also associated with higher plasma levels of total (4.2 vs. 4.7 mmol/l, P = 0.02) and LDL cholesterol (2.4 vs. 2.9 mmol/l, P = 0.02) in the control group, as was SNP V1119V (P = 0.04 and P = 0.03, respectively). SNPs F549F and V1119V were associated with higher systolic blood pressure (P = 0.04 and P = 0.02, respectively). There were no differences in the parameters of glucose metabolism between the genotype groups.

CONCLUSIONS

Genetic variation in LRP5 did not predispose to PA but was associated with metabolic characteristics, especially lipid profile, in healthy prepubertal children.

ACTH receptor promoter polymorphism associates with severity of premature adrenarche and modulates hypothalamo-pituitary-adrenal axis in children

The genetic mechanisms underlying the regulation of adrenarche are unknown. The aim of the study was to find out whether ACTH receptor (MC2R) promoter polymorphism associates with premature adrenarche (PA) and its characteristics. DNA samples of 74 prepubertal children with PA and their age- and gender-matched 97 healthy controls were genotyped for the -2 bp T/C diallelic MC2R promoter polymorphism (MC2R -2 T>C) All children were examined clinically, and hormonal measurements after an overnight fast and a low-dose ACTH stimulation test were performed. In controls, the baseline ACTH/cortisol ratio was significantly higher (p = 0.002) in subjects with the polymorphism than in the T/T group indicating decreased ACTH sensitivity. The frequency of the MC2R -2 T>C polymorphism was significantly higher in PA children with premature pubarche than in those with milder signs of PA or in control children (p = 0.04). In children with PA, the polymorphism associated with higher baseline serum dehydroepiandrosterone (p = 0.03), androstenedione (p = 0.02), plasma ACTH (p = 0.03) levels and with lower birth weight (p = 0.02). Our study provides evidence that the MC2R promoter polymorphism modulates the hypothalamo-pituitary-adrenal axis in children and may play a role in altered regulation of adrenarche.

Association of the GAA1013→GAG polymorphism of the insulin-like growth factor-1 receptor (IGF1R) gene with premature pubarche

OBJECTIVE

A single-nucleotide polymorphism (SNP), the G variant in codon 1013 (GAA1013-->GAG) of the insulin-like growth factor-1 (IGF-1) receptor (IGFIR) gene, has been associated with higher IGF-1 concentrations in Caucasian subjects. Because elevated serum levels of IGF-1 have been described in children with premature pubarche (PP) and in adolescent girls with hyperandrogenism, we tested the a priori hypothesis that the frequency of the A-->G variant would be overrepresented among children with PP.

DESIGN

Case-control association study.

SETTING

University-based pediatric endocrinology practice.

PATIENT(S)

Sixty-nine children (63 girls and 6 boys) with PP, 52 adolescent girls with hyperandrogenism, and 92 healthy subjects.

INTERVENTION(S)

Blood was obtained for genotype analysis, glucose measurement, and hormone (A, insulin, 17-hydroxyprogesterone, and T) determinations.

MAIN OUTCOME MEASURE(S)

Frequency of the SNP in the IGF1R gene and correlation of this SNP with hormone concentrations.

RESULT(S)

Distribution of the G allele was statistically significantly different between the children with PP and the healthy control subjects, independent of insulin sensitivity.

CONCLUSION(S)

This common SNP in the IGF1R gene may be associated with PP caused by premature adrenarche in children. Because PP has been associated with higher IGF-1 concentrations, these data suggest a potential molecular basis for prior clinical observations of elevated IGF-1 concentrations in children with PP.

[Mutation screening in Angiotensin II receptors, AGTR1 and AGTR2, and evaluation of AGTR1 polymorphisms C573T and A1166C in patients with premature adrenarche]

Precocious pubarche is the appearance of pubic hair before the age of 8 years in girls and 9 years in boys. The most frequent etiology is idiopathic precocious adrenarche, suggested, after long-term follow-up, to be associated with metabolic syndrome. One of the factors involved in the genesis of precocious adrenarche is Angiotensin II (Ang II), which promotes cell proliferation and steroidogenesis through type 1 (AT1) and type 2 (AT2) receptors. In order to study Ang II receptors mutations, 50 children with idiopathic precocious adrenarche were evaluated and compared to a control group of normal individuals. Mutations were not detected in the AGTR1 and AGTR2 genes; however, two polymorphisms were identified in the AGTR1 gene: the C573T (exon 5) and the A1166C (3' untranslated region). The polymorphic allele T573 was found in 35% of the patients and 38% of controls. The polymorphic allele C1166 was present in 24% of the patients and 26% of controls. There was no statistical difference between groups. There was also no correlation between the polymorphisms and clinical and laboratory findings, as well as their family history of metabolic syndrome.

Puberty and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous familial disorder characterized by chronic anovulation and hyperandrogenism. This multi-system, polygenic, multi-factorial disorder is associated with an increased risk for metabolic abnormalities such as type 2 diabetes mellitus. Signs and symptoms of PCOS often emerge during the peri-pubertal years with premature pubarche (PP) being the earliest manifestation for some girls. Insulin resistance and hyperinsulinemia are important pathophysiological features that are common to both PP and PCOS. Future investigations are needed to uncover the relevant genetic and hormonal factors and identify effective interventions.

Position of the American Dietetic Association: individual-, family-, school-, and community-based interventions for pediatric overweight

The American Dietetic Association (ADA), recognizing that overweight is a significant problem for children and adolescents in the United States, takes the position that pediatric overweight intervention requires a combination of family-based and school-based multi-component programs that include the promotion of physical activity, parent training/modeling, behavioral counseling, and nutrition education. Furthermore, although not yet evidence-based, community-based and environmental interventions are recommended as among the most feasible ways to support healthful lifestyles for the greatest numbers of children and their families. ADA supports the commitment of resources for programs, policy development, and research for the efficacious promotion of healthful eating habits and increased physical activity in all children and adolescents, regardless of weight status. This is the first position paper of ADA to be based on a rigorous systematic evidence-based analysis of the pediatric overweight literature on intervention programs. The research showed positive effects of two specific kinds of overweight interventions: a) multicomponent, family-based programs for children between the ages of 5 and 12 years, and b) multicomponent, school-based programs for adolescents. Multicomponent programs include behavioral counseling, promotion of physical activity, parent training/modeling, dietary counseling, and nutrition education. Analysis of the literature to date points to the need for further investigation of promising strategies not yet adequately evaluated. Furthermore, this review highlights the need for research to develop effective and innovative overweight prevention programs for various sectors of the population, including those of varying ethnicities, young children, and adolescents. To support and enhance the efficacy of family- and school-based weight interventions, community-wide interventions should be undertaken; few such interventions have been conducted and even fewer evaluated.

Abnormal glucose tolerance and insulin resistance in polycystic ovary syndrome amongst the Taiwanese population- not correlated with insulin receptor substrate-1 Gly972Arg/Ala513Pro polymorphism

Background

Insulin resistance and glucose dysmetabolism in polycystic ovary syndrome (PCOS) are related with the polymorphisms in the genes encoding the insulin receptor substrate (IRS) proteins, especially Gly972Arg/Ala513Pro polymorphism being reported to be associated with type-2 diabetes and PCOS. We intended to assess the prevalence of abnormal glucose tolerance (AGT) and insulin resistance in Taiwanese PCOS women. We also tried to assess whether the particular identity of Gly972Arg/Ala513Pro polymorphic alleles of the IRS-1 gene mutation can be used as an appropriate diagnostic indicator for PCOS.

Methods

We designed a prospective clinical study. Forty-seven Taiwanese Hoklo and Hakka women, diagnosed with PCOS were enrolled in this study as were forty-five healthy Hoklo and Hakka women as the control group. Insulin resistance was evaluated with fasting insulin, fasting glucose/insulin ratio, and homeostasis model assessment index for insulin resistance (HOMA_IR). The genomic DNA of the subjects was amplified by PCR and digested by restriction fragmented length polymorphism (RFLP) with Bst N1 used for codon 972 and Dra III for codon 513.

Results

AGT was found in 46.8% of these PCOS patients and was significantly related to high insulin resistance rather than the low insulin resistance. Those patients with either insulin resistance or AGT comprised the majority of PCOS affected patients (AGT + fasting insulin ≥17: 83%, AGT + glucose/insulin ratio ≥6.5: 85.1%, AGT + HOMA_IR ≥ 2: 87.2%, and AGT + HOMA_IR ≥ 3.8: 72.3%). None of the tested samples revealed any polymorphism due to the absence of any Dra III recognition site or any Bst N1 recognition site in the amplified PCR fragment digested by restriction fragmented length polymorphism.

Conclusion

There is significantly high prevalence of AGT and insulin resistance in PCOS women, but Gly972Arg and Ala513Pro polymorphic alleles of IRS-1 are rare and are not associated with the elevated risk of PCOS amongst Taiwanese subjects. This is quite different from the similar study in phylogenetically diverged Caucasian subjects.

Association of Gly972Arg variant of insulin receptor substrate-1 with metabolic features in women with polycystic ovary syndrome

OBJECTIVE

To examine the prevalence and the effects of Gly972Arg (G972A) variant of insulin receptor substrate-1 (IRS-1) in women with polycystic ovary syndrome (PCOS).

DESIGN

Controlled clinical study.

SETTING

An academic clinical research center.

PATIENT(S)

Sixty women with PCOS and 60 control women matched for age.

INTERVENTION(S)

Biometric measures, metabolic and hormonal measures, genetic analyses.

MAIN OUTCOME MEASURE(S)

Serum androgens, glucose, and insulin were measured. Blood leukocytes were used for genetic analyses.

RESULT(S)

The G972A variant was encountered more often in women with PCOS. The G972A carriers were more obese than their counterparts, had higher fasting insulin levels, and were more insulin-resistant. However, androgen levels did not differ on the basis of IRS-1 genotype.

CONCLUSION(S)

We observed that the G972A variant of IRS-1 was more prevalent in women with PCOS, and that it had important metabolic effects without having a direct effect on the androgen levels. However, the G972A variant of IRS-1 may modulate reproduction by lowering sex hormone-binding globulin in both healthy women and women with PCOS.

Polymorphisms in the insulin receptor substrate-1 (IRS-1) gene and the insulin receptor substrate-2 (IRS-2) gene influence glucose homeostasis and body mass index in women with polycystic ovary syndrome and non-hyperandrogenic controls

BACKGROUND

We aimed to evaluate the influence of the Gly972Arg variant of the insulin receptor substrate-1 gene (IRS-1) and the Gly1057Asp variant in IRS-2 on insulin resistance and glucose tolerance in women with polycystic ovary syndrome (PCOS) and healthy controls.

METHODS

Genotypes, allelic frequencies, indexes of insulin resistance, glucose tolerance and hormone profiles were studied in a large sample of Spanish PCOS (n = 103) women compared with a control group (n = 48) of healthy women matched for body mass index.

RESULTS

No differences in genotype or allelic frequencies were found between PCOS patients and healthy controls. When considering control subjects and PCOS patients as a whole, IRS-1 Arg972 carriers also presented with increased fasting insulin (133 +/- 60 versus 95 +/- 67 pmol/l, P = 0.008) and insulin resistance measured by homeostasis model assessment (4.3 +/- 2.1 versus 3.1 +/- 2.4, P = 0.009) compared with subjects homozygous for Gly972 alleles. These differences were even higher when restricting the analysis to PCOS patients. Subjects homozygous for the Gly1057 allele of IRS-2 presented with increased 60 and 90 min oral glucose tolerance test (OGTT) glucose levels compared with carriers of one or two Asp1057 alleles (7.9 +/- 2.1 versus 7.1 +/- 2.1 mmol/l, P = 0.042 and 7.0 +/- 2.1 versus 6.0 +/- 1.8 mmol/l, P = 0.014), and a similar tendency was observed for 120 min OGTT glucose levels.

CONCLUSIONS

The Gly972Arg in IRS-1 and Gly1057Asp in IRS-2 polymorphisms influence glucose homeostasis in premenopausal women, but are not associated with PCOS.

The molecular-genetic basis of functional hyperandrogenism and the polycystic ovary syndrome

The genetic mechanisms underlying functional hyperandrogenism and the polycystic ovary syndrome (PCOS) remain largely unknown. Given the large number of genetic variants found in association with these disorders, the emerging picture is that of a complex multigenic trait in which environmental influences play an important role in the expression of the hyperandrogenic phenotype. Among others, genomic variants in genes related to the regulation of androgen biosynthesis and function, insulin resistance, and the metabolic syndrome, and proinflammatory genotypes may be involved in the genetic predisposition to functional hyperandrogenism and PCOS. The elucidation of the molecular genetic basis of these disorders has been burdened by the heterogeneity in the diagnostic criteria used to define PCOS, the limited sample size of the studies conducted to date, and the lack of precision in the identification of ethnic and environmental factors that trigger the development of hyperandrogenic disorders. Progress in this area requires adequately sized multicenter collaborative studies after standardization of the diagnostic criteria used to classify hyperandrogenic patients, in whom modifying environmental factors such as ethnicity, diet, and lifestyle are identified with precision. In addition to classic molecular genetic techniques such as linkage analysis in the form of a whole-genome scan and large case-control studies, promising genomic and proteomic approaches will be paramount to our understanding of the pathogenesis of functional hyperandrogenism and PCOS, allowing a more precise prevention, diagnosis, and treatment of these prevalent disorders.

Prevalence of CYP21 mutations and IRS1 variant among women with polycystic ovary syndrome and adrenal androgen excess

OBJECTIVE

To determine whether frequencies of the mutations in the 21-hydroxylase (CYP21) gene and the G972R variant of the insulin receptor substrate-1 (IRS1) gene are increased in women with polycystic ovary syndrome (PCOS) and adrenal androgen (AA) excess.

DESIGN

Prospective case-control study.

SETTING

University reproductive endocrinology laboratory and outpatient clinic.

PATIENT(S)

Consecutive patients of non-Hispanic white race diagnosed with PCOS (n = 114) and healthy controls (n = 95).

INTERVENTION(S)

Blood and DNA sampling before hormonal therapy.

MAIN OUTCOME MEASURE(S)

Polycystic ovary syndrome patient and healthy control genotypes, with the CYP21 and IRS1 variants.

RESULT(S)

Fifty-four PCOS patients with (DHEAS >3000 ng/mL) and 55 without (DHEAS <2500 ng/mL) AA excess, respectively, were studied. Of 109 patients studied, 16 (14.7%) were found to be heterozygous carriers of mutations in the CYP21 gene. Of these 16, 10 (62.5%) had excessive AA secretion (i.e., excess DHEAS levels). Fifteen patients (13.8%) were found to be heterozygous carriers of the IRS1 variant; 9 (60.0%) of these 15 had excessive AA secretion. There were no significant differences in the allele frequency of CYP21 mutations or the IRS1 variant between PCOS patients with and without AA excess, and controls. None of the subjects were found to be homozygous carriers of CYP21 mutations or the IRS1 variant. Combined heterozygosity for CYP21 mutations and the IRS1 variant was limited to women with PCOS and excessive AA (n = 3).

CONCLUSION(S)

The G972R variant of the IRS1 gene might represent a modifier locus among women who are heterozygous carriers of CYP21 mutations, potentially increasing their risk of developing AA excess in PCOS. Nonetheless, this IRS1 variant and CYP21 mutations seem to play a limited role in the development of PCOS in the population studied.

Genetic contributions to glucose intolerance in polycystic ovary syndrome

Women with polycystic ovary syndrome (PCOS) are predisposed to develop impaired glucose tolerance and type-2 diabetes mellitus. Genetic factors appear to contribute to the insulin resistance that is characteristic of PCOS as well as to the failure of the pancreatic beta-cell to compensate adequately for this insulin resistance. The cumulative results of studies examining the genetic contribution to both the reproductive and metabolic phenotypes of PCOS are consistent with PCOS as a complex, polygenic disorder. This article reviews the background and recent studies examining the genetic contributions to glucose intolerance in PCOS.

The importance of IRS-1 Gly972Arg polymorphism in evaluating the response to metformin treatment in polycystic ovary syndrome

BACKGROUND

Recent evidence suggests that one of the modes of action of metformin may be through phosphorylation of the insulin receptor and insulin receptor substrates. With this in mind, we supposed that the G972A variant of insulin receptor substrate-1 (IRS-1) may modulate the response to metformin treatment in women with polycystic ovary syndrome (PCOS).

METHODS

This preliminary study involved 60 randomly selected women with PCOS. All patients received dietary instructions and metformin 500 mg three times daily for 6 months. Main outcome measures were androgen levels, parameters of glucose and insulin metabolism and anthropometric variables. After a second evaluation of the patients at 6 months, they were genotyped for the Gly972Arg variant of the IRS-1 gene.

RESULTS

Metformin had differential effects on fasting insulin levels, insulin resistance as demonstrated by homeostasis model assessment (HOMA), LH, total testosterone, dehydroepiandrosterone sulphate and free testosterone index on the basis of IRS genotype. The response to metformin therapy in other parameters was not different according to IRS genotype.

CONCLUSION

There was a differential effect of metformin therapy in PCOS women on the basis of IRS genotype. This study may call attention to the importance of molecular markers in the management of women with PCOS.

Mutational analysis of the melanocortin-4 receptor (MC4R) gene in children with premature pubarche and adolescent girls with hyperandrogenism

To determine if variants in the melanocortin-4 receptor (MC4R) gene are associated with premature pubarche (PP) in children and hyperandrogenism (HA) in adolescent girls, we performed single-strand conformational polymorphism (SSCP) in 75 children (69 girls/six boys) with PP, 53 adolescent girls with HA, and 95 healthy adult control subjects. DNA sequence analysis of the conformers identified by SSCP revealed variants in six patients (two silent and one missense) and in none of the control subjects.

Genetic Basis of Metabolic Abnormalities in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common heterogeneous disorder characterized by hyperandrogenism and chronic anovulation. The syndrome is frequently associated with an increased risk for insulin resistance and type 2 diabetes mellitus; obesity exacerbates insulin resistance and favors the progression from impaired glucose tolerance to diabetes in these patients. In young women, precocious pubarche and hyperinsulinemia are early manifestations of PCOS. The familial clustering of women with PCOS suggests that heredity is implicated in the origin of the syndrome. However, genetic approaches to its pathogenesis have been hampered by the heterogeneity of phenotypic features within families, and the lack of uniform criteria for diagnosis. Currently, PCOS is considered a polygenic trait that might result from the interaction of susceptibility and protective genomic variants under the influence of environmental factors. Both linkage analysis and association studies are valid tools for the study of the genetics of PCOS. Candidate genes for PCOS include those related to androgenic pathways and metabolic associations of the syndrome. More recently, genes encoding inflammatory cytokines have been identified as target genes for PCOS, as proinflammatory genotypes and phenotypes are also associated with obesity, insulin resistance, type 2 diabetes, PCOS, and increased cardiovascular risk. This paper reviews the candidate genes involved in the metabolic pathways that are altered in patients with PCOS. Despite a significant amount of research in this area, none of the genes studied so far has been identified as the PCOS susceptibility gene for the majority of cases. PCOS is the first component of the metabolic syndrome to be detected in many women, so the identification and correct diagnosis of PCOS has important preventive and therapeutic implications for the affected women and their families. In the future, new therapeutic approaches to PCOS will rely on knowing the genes, environmental influences, and etiologic mechanisms associated with the disorder.

The Management of Polycystic Ovary Syndrome

It is well known that subjects with polycystic ovary syndrome (PCOS) show very variable clinical and biochemical aspects. Considering long-term repercussions, two main disturbances, not always strictly related, need to be countered: hyperandrogenism and insulin resistance, with compensatory hyperinsulinemia. The aim of this review is to summarize therapeutic perspectives for PCOS, starting from basic approach, such as weight reduction and changes in lifestyle. The benefits of long-term use of oral contraceptives and the criteria of choice of the estro-progestin combinations are discussed. With severe hyperandrogenism, a pure antiandrogen should be added. The experiences with insulin-sensitizing drugs, especially metformin, are reviewed; while their beneficial role as an adjuvant to treatment of ovulatory infertility has been well established, the effects of a long-term treatment, especially in very young patients, are still under debate. Current studies are testing the results of combinations of different treatments at low dosage; randomized comparative trials on the long-term efficacy of these approaches have yet to be scheduled.

Frequency of the T228A polymorphism in the SORBS1 gene in children with premature pubarche and in adolescent girls with hyperandrogenism

OBJECTIVE

Because the metabolic actions of insulin are more impaired than the mitogenic pathways in polycystic ovary syndrome (PCOS), genes coding for proteins involved in insulin-mediated glucose transport can be considered as candidate genes. The sorbin and SH3-domain-containing-1 (SORBS1) gene codes for c-Cbl-associated protein (CAP) involved in insulin-mediated glucose uptake. An association study showed that a missense variant of the SORBS1 gene is protective against obesity and diabetes. We tested the hypothesis that the frequency of the protective allele would be decreased in children with premature pubarche and adolescent girls with hyperandrogenism.

DESIGN

Association study.

SETTING

Academic research environment.

PATIENT(S)

Children referred for the evaluation of premature pubarche (n = 79), adolescent girls with hyperandrogenism (n = 56), and healthy nondiabetic controls (n = 50).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Frequency of the T228A allele in our patients and the relationship of body mass index to presence or absence of the T228A variant in our patient population.

RESULT(S)

Using allele-specific restriction fragment length polymorphism, allele frequencies were found to be similar among the premature pubarche, hyperandrogenism, and control groups (6.0%, 4.6%, and 8.0%, respectively). No statistically significant relationships were found between the SORBS1 genotypes and body mass index or hormone status.

CONCLUSION(S)

This SORBS1 polymorphism does not play a major role in premature pubarche, hyperandrogenism, and/or polycystic ovary syndrome in our patient population.

Increased frequency of the G972R variant of the insulin receptor substrate-1 (irs-1) gene among girls with a history of precocious pubarche

To test the hypothesis that lower sex hormone-binding globulin (SHBG) concentrations are associated with heterozygosity for the G972R variant of the IRS-1 gene among adolescent girls with a history of precocious pubarche (PP) and hyperinsulinemic ovarian hyperandrogenism.Association study. Academic research environment. Adolescent girls with a history of PP and healthy adolescent female control subjects. Determine body mass index; measure serum androgen, insulin-like growth factor (IGF)-binding protein 1, lipids, IGF-1, and SHBG concentrations; perform glucose tolerance tests; and assay for G972R variant of the IRS-1 gene. Serum androgen, IGFBP-1, and SHBG concentrations; IRS-1 genotypes.Twenty-five of 54 (45%) girls with a history of PP developed hyperinsulinemic ovarian hyperandrogenism at adolescence. Frequency of heterozygosity for G972 was 31% among girls with a history of PP, 40% among girls with hyperinsulinemic ovarian hyperandrogenism, and 19% among healthy control subjects. Sex hormone-binding globulin concentrations were lower among girls heterozygous for G972R variant. Predictors of progression from PP to hyperinsulinemic ovarian hyperandrogenism included chronological age, insulin, low-density lipoprotein cholesterol, and IGFBP-1 concentrations. The low mean SHBG concentration found among G972R carriers suggests that this variant may be a minor locus associated with development of hyperinsulinemic insulin resistance and ovarian androgen excess in girls with a history of PP.

Inter- and intrafamilial variability in premature pubarche and polycystic ovary syndrome

OBJECTIVE

To ascertain the extent of phenotypic heterogeneity for premature pubarche and polycystic ovary syndrome between and within families.

DESIGN

Association study.

SETTING

Academic research environment.

PATIENT(S)

Three families in which the propositus had presented with either premature pubic hair or adolescent hyperandrogenism.

INTERVENTION(S)

Detailed medical histories, hormone determinations, and genotype analyses.

MAIN OUTCOME MEASURE(S)

Clinical phenotype. Genotypes for CYP21, HSD3B2, G972R variant of IRS-1, N363S variant of GRL, W64R variant of ADRB3, CAG repeat in exon 1 of AR, MspAI polymorphism in CYP17, and R264C variant of CYP19.

RESULT(S)

Significant phenotypic and genetic heterogeneity was observed both within and between families. In one family, CYP21 and IRS-1 variants were observed to co-segregate with symptoms of androgen excess and obesity. No genetic markers were consistently noted to associate with clinical features of hyperandrogenism in the other two families.

CONCLUSION(S)

The difficulties in classifying female family members as clearly affected or unaffected and lack of definitive male phenotype complicate the use of linkage analysis to identify the polycystic ovary syndrome genes. Each family is best considered on an individual basis to identify genetic markers that segregate with the clinical features of androgen excess.

Relationship of insulin receptor substrate-1 and -2 genotypes to phenotypic features of polycystic ovary syndrome

Insulin resistance is a key component in the pathogenesis of polycystic ovary syndrome (PCOS) and type 2 diabetes. Polymorphisms in the genes encoding the insulin receptor substrate (IRS) proteins, IRS-1 (Gly(972)Arg) and IRS-2 (Gly(1057)Asp), influence susceptibility to type 2 diabetes. This study was undertaken to assess the influence of these polymorphisms on insulin resistance, glucose tolerance, and androgen levels in nondiabetic PCOS women. We studied 227 PCOS subjects including 126 and 48 nondiabetic white and African-American subjects, respectively. The IRS-1 Gly(972)Arg allele frequencies were identical in whites and African-Americans [0.95 (Gly) and 0.05 (Arg)]. The IRS-2 Gly(1057)Asp allele frequencies were 0.85 (Gly) and 0.15 (Asp) in African-Americans and 0.59 (Gly) and 0.41 (Asp) in whites. There was no association of IRS-1 genotype with any clinical or hormonal measure in nondiabetic white or African-American PCOS subjects. However, nondiabetic subjects with the IRS-2 Gly/Gly genotype had significantly higher 2-h oral glucose tolerance test glucose levels compared with those with Gly/Asp and Asp/Asp genotypes in whites or Gly/Asp genotype in African-Americans (there were no Asp/Asp subjects in our modest size African-American sample). These results suggest that the IRS-2 Gly(1057)Asp polymorphism influences blood glucose levels in nondiabetic white and African-American women with PCOS. Thus, individuals with the common IRS-2 Gly/Gly genotype may be at increased risk of developing type 2 diabetes.

Reproductive characteristics of cloned heifers derived from adult somatic cells

This study examined the onset of puberty, follicular dynamics, reproductive hormone profiles, and ability to maintain pregnancy in cloned heifers produced by somatic cell nuclear transfer. Four adult somatic cell-cloned heifers, derived from a 13-yr-old Holstein cow, were compared to 4 individual age- and weight-matched heifers produced by artificial insemination (AI). From 7 to 9 mo of age, jugular venous blood samples were collected twice weekly, and from 10 to 11 or 12 mo of age, blood sampling was carried out every other day. After the heifers reached puberty (defined as the first of 3 consecutive blood samples with peripheral plasma progesterone concentrations of >1 ng/ml), ultrasound examination of ovaries and jugular plasma sample collection were carried out daily for 1 estrous cycle. Cloned heifers reached puberty later than controls (mean +/- SEM, 314.7 +/- 9.6 vs. 272 +/- 4.4 days and 336.7 +/- 13 vs. 302.8 +/- 4.5 kg for clones and controls, respectively; P < 0.05). However, cloned and control heifers were not different in estrous cycle length, ovulatory follicle diameter, number of follicular waves, or profiles of hormonal changes (LH, FSH, estradiol, and progesterone). Three of the 4 clones and all 4 control heifers became pregnant after AI. These results demonstrate that clones from an aged adult have normal reproductive development.