Flutamide metformin for post-menarcheal girls with preclinical ovarian androgen excess: evidence for differential response by androgen receptor genotype

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.

Comparison of the effects of metformin, flutamide plus oral contraceptives, and simvastatin on the metabolic consequences of polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the common endocrine disorders in women of reproductive ages. It is associated with a range of disorders, such as dyslipidemia, hypertension, insulin resistance (IR), compensatory hyperinsulinemia, gestational, and type 2 diabetes, and increased risk of cardiovascular morbidity. There are different treatments available for PCOS. The purpose of this study was to determine and compare the effects of metformin, flutamide plus oral contraceptives (OCs), and simvastatin on the metabolic consequences of PCOS.

MATERIALS AND METHODS

This study was a single-blind clinical trial. The subjects were selected from a group of patient with PCOS and metabolic syndrome, who were referred to the midwifery clinic of Al-Zahra Hospital and Beheshti Hospital, Isfahan, Iran. A total of 111 subjects were randomly assigned to three groups: metformin, flutamide plus OCs, and simvastatin groups. The measurements were performed at baseline and after 6 months of therapy. Paired t-test, analysis of variance (ANOVA), and chi-square test were applied in this study.

RESULTS

A total of 102 subjects were analyzed in this study, 34 subjects were allotted in each group. The prevalence of IR was statistically different between three groups (P-value = 0.001). After a 6-month course, metformin showed larger reduction in fasting blood sugar (FBS) level (P-value < 0.001). However, except for metformin, two other treatments reduced C-reactive protein (CRP) level significantly (both P-values < 0.001). The level of triglycerides (TGs) decreased considerably in all groups (all P-values < 0.001). Both metformin and simvastatin decreased BMI significantly (both P-values < 0.001). None of the treatments changed high-density lipoprotein (HDL) level (all P-values > 0.05).

CONCLUSION

Metformin performed better in FBS reduction. Simvastatin had better performance in terms of reducing TG level and waist circumference.

Systemic therapy of androgenic alopecia

The article describes the literature sources related to the efficacy of systemic therapy of androgenic alopecia in female and male.

Fatty acid-binding protein-4 plasma levels are associated to metabolic abnormalities and response to therapy in girls and young women with androgen excess

OBJECTIVE

To assess the usefulness of circulating fatty acid-binding protein 4 (FABP4) as a predictive marker of long-term therapeutic outcome in girls with ovarian androgen excess and a history of precocious pubarche (PP) and low birth weight (LBW) and in young women with polycystic ovary syndrome (PCOS).

METHODS

We included 97 patients. Thirty-nine had a history of LBW-PP and were randomized to remain untreated (n = 13) or to receive metformin (n = 26). PCOS women (n = 58) received low-dose flutamide-metformin plus an oral contraceptive. Auxology, androgens, glucose, insulin, homeostasis model assessment (HOMA)-insulin resistance (IR), lipid profile, FABP4, and body composition (by dual-energy X-ray absorptiometry) were assessed at baseline and after 2 years.

RESULTS

At baseline, FABP4 was associated with anthropometric measurements and fat body mass (all P < 0.05). FABP4 levels increased less after follow-up in the PP-treated girls (P < 0.05); in the PCOS patients, basal FABP4 levels were inversely associated with changes in systolic blood pressure, HOMA-IR, and total fat mass (all P < 0.05). Body mass index-standard deviation scores was the main independent predictor of FABP4 variations (33%, P < 0.001).

CONCLUSION

FABP4 is a strong clinical biomarker of adiposity, IR, and the presence of the components of the metabolic syndrome in non-obese hyperandrogenic girls and young women; pretreatment FABP4 levels appear to predict therapeutic long-term response.

A single nucleotide polymorphism in STK11 influences insulin sensitivity and metformin efficacy in hyperinsulinemic girls with androgen excess

OBJECTIVE

Serine-threonine kinase STK11 catalyzes the AMP-activated protein kinase complex. We tested the hypothesis that a gene variant in STK11 contributes to variation in insulin sensitivity and metformin efficacy.

RESEARCH DESIGN AND METHODS

We studied the effects of a single nucleotide polymorphism (SNP) (rs8111699) in STK11 on endocrine-metabolic and body composition indexes before and after 1 year of metformin in 85 hyperinsulinemic girls with androgen excess, representing a continuum from prepuberal girls with a combined history of low birth weight and precocious pubarche over to postmenarchial girls with hyperinsulinemic ovarian hyperandrogenism. Metformin was dosed at 425 mg/day in younger girls and 850 mg/day in older girls. STK11 rs8111699 was genotyped. Endocrine-metabolic features were assessed in the fasting state; body composition was estimated by absorptiometry.

RESULTS

Genotype effects were similar in younger and older girls. At baseline, the mutated G allele in STK11 rs8111699 was associated with higher insulin and IGF-I levels (both P < 0.005). The response to metformin differed by STK11 genotype: GG homozygotes (n = 24) had robust metabolic improvements, GC heterozygotes (n = 38) had intermediate responses, and CC homozygotes (n = 23) had almost no response. Such differences were found for 1-year changes in body composition, circulating insulin, IGF-I, free androgen index, and lipids (all P < 0.005).

CONCLUSIONS

In hyperinsulinemic girls with androgen excess, the STK11 rs8111699 SNP influences insulin sensitivity and metformin efficacy, so that the girls with the least favorable endocrine-metabolic profile improve most with metformin therapy.

Pharmacogenetics of testosterone replacement therapy

Variable phenotypes of androgen insensitivity exist in humans, mainly owing to defective, mutated androgen receptors. A more subtle modulation of androgen effects is related to the CAG repeat polymorphism ([CAG]n) in exon 1 of the androgen receptor gene, in vitro, transcription of androgen-dependent target genes is attenuated with increasing length of triplets. As a clinical entity, the CAG repeat polymorphism can relate to variations of androgenicity in (apparently) eugonadal men in various tissues and psychological traits, the longer the (CAG)n, the less prominent the androgen effect when individuals with similar testosterone concentrations are compared. A strictly defined threshold to hypogonadism is likely to be replaced by a continuum spanned by genetics as well as symptom specificity. In addition, effects of externally applied testosterone can be markedly influenced by the (CAG)n and respective pharmacogenetic implications are likely influence indications as well as modalities of testosterone treatment of hypogonadal men.

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.

Androgen receptor gene CAG repeat polymorphism and X-chromosome inactivation in children with premature adrenarche

CONTEXT

There is variation in the adrenal androgen levels and clinical findings of children with premature adrenarche (PA).

OBJECTIVES

We hypothesized that androgen sensitivity, indicated by the length of CAG repeat in the X-chromosomal androgen receptor (AR) gene has a role in the polygenic pathogenesis of PA.

DESIGN AND PATIENTS

We performed a cross-sectional association study among 73 Finnish Caucasian children with PA (10 boys and 63 girls) and 97 age- and gender-matched healthy controls (18 boys and 79 girls).

MAIN OUTCOME MEASURES

AR gene methylation-weighted CAG(n)(mwCAG(n)) via CAG(n) length and X-chromosome inactivation analysis and clinical phenotype were determined.

SETTING

The study took place at a university hospital.

RESULTS

PA subjects had significantly shorter mwCAG(n) than controls [mean difference (95% confidence interval); 0.76 (0.14-1.38); P = 0.017]. AR gene mwCAG(n) did not correlate with androgen or SHBG levels in either group. In children with PA, mwCAG(n) correlated positively with body mass index (BMI) (tau = 0.19; P = 0.02). The mean of mwCAG(n) was significantly shorter in PA children with lower BMI compared with PA children with higher BMI [BMI sd score < 0.79, n = 35, vs. BMI sd score > 0.79, n = 36; 1.13 (0.38-1.87), P = 0.004] and in PA children with lower BMI compared with healthy children with same BMI (P = 0.004).

CONCLUSIONS

The AR gene CAG(n) polymorphism may have a significant role in the pathogenesis of PA, especially in lean children.