Androgen receptor gene CAG repeat length in women with metabolic syndrome

Revisiting the relationships of 2D:4D with androgen receptor (AR) gene and current testosterone levels: Replication study and meta-analyses

The relationships of digit ratio (2D:4D) with the length of AR (CAG)n, and testosterone levels from saliva and blood have been extensively debated over the years. This research including three studies further clarifies such controversies. To do so, we re-examined the relationships between the length of AR (CAG)n, 2D:4D, and current testosterone levels, through replication study and meta-analysis for each study. The results indicate: (a) the length of AR (CAG)n is not significantly associated with 2D:4D; (b) current testosterone levels are not significantly associated with the ratio; and (c) the length is not significantly associated with testosterone levels. Thus, AR (CAG)n and current testosterone levels are not significantly related to 2D:4D at individual level.

Androgen receptor (CAG)n polymorphism and androgen levels in women with systemic lupus erythematosus and healthy controls

Systemic lupus erythematosus (SLE) is an autoimmune disorder that affects mainly females. Therefore, interrelations between the reproductive and immune system have been assumed. Considering the complex influence of hormones and receptors, we aimed to investigate the influence of androgens and androgen receptor (AR) polymorphism in women with SLE. One hundred and sixteen patients and 44 healthy women were investigated. Testosterone, sex hormone-binding globulin (SHBG), dehydroepiandrosterone-sulphate (DHEAS) concentrations and AR (CAG)n polymorphism were determined. SLE patients had significantly lower levels of total and free testosterone and DHEAS in comparison with the controls. No differences in the CAG repeat length between the groups were established. Women with two alleles carrying more than 22 CAG repeats had significantly higher levels of SHBG (101.51 ± 61.81 vs. 69.22 ± 45.93 nmol/l, p = 0.015) and DHEAS (3.11 ± 2.65 vs. 2.11 ± 3.06 μmol/l, p = 0.007) and a tendency to higher testosterone concentrations (2.35 ± 2.10 vs. 1.71 ± 1.70 nmol/l, p = 0.056) in comparison with other women. The CAG repeat length in the relatively longer (CAG)n allele was inversely related to the Systemic Lupus International Collaborating Clinics/ACR index (r = -0.258, p = 0.009). In conclusion, the androgen receptor (CAG)n polymorphism is not related to the development of SLE, but it could modulate the severity of the lupus chronic damages as well as the androgen levels in women.

The role of androgens in follicle maturation and ovulation induction: friend or foe of infertility treatment?

BACKGROUND

Effects of androgens on follicle maturation have been controversial for some time. Here, we review the potential of their applications in improving human ovulation induction, based on human and animal data, reported in the literature.

METHODS

We reviewed the published literature for the years 2005-2011, using relevant key words, in PubMed, Medline and Cochrane reviews, and then performed secondary reviews of referenced articles, which previously had not been known or preceded the searched time period. A total of 217 publications were reviewed.

RESULTS

Contrary to widely held opinion, recent data, mostly developed in the mouse, convincingly demonstrate essential contribution of androgens to normal follicle maturation and, therefore, female fertility. Androgens appear most engaged at preantral and antral stages, primarily affect granulosa cells, and exert effects via androgen receptors (AR) through transcriptional regulation but also in non-genomic ways, with ligand-activated AR modulating follicle stimulating hormone (FSH) activity in granulosa cells. While some androgens, like testosterone (T) and dehydroepiandrosterone (DHEA), appear effective in improving functional ovarian reserve (FOR) in women with diminished ovarian reserve (DOR), others may even exert opposite effects. Such differences in androgens may, at least partially, reflect different levels of agonism to AR.

DISCUSSION

Selective androgens appear capable of improving early stages of folliculogenesis. They, therefore, may represent forerunners of a completely new class of ovulation-inducing medications, which, in contrast to gonadotropins, affect follicle maturation at much earlier stages.

Androgens and polycystic ovary syndrome

PURPOSE OF REVIEW

Polycystic ovary syndrome (PCOS) is a common complex endocrine genetic disorder, which involves overproduction of androgens, leading to heterogeneous range of symptoms and associated with increased metabolic and cardiovascular morbidity. This review focuses on androgen biosynthesis, use, metabolism in PCOS and clinical consequences of hyperandrogenism.

RECENT FINDINGS

Controversial definition of the disorder and different phenotypic subgroups present a challenge for clinical and basic research. Further investigation of different phenotypes highlights the fact that PCOS probably represents a group of disorders with different etiologies. Prenatal androgen exposure and adolescent studies suggest early in life androgen excess as initiating factor of PCOS, but insufficient evidence available to confirm this hypothesis. Various intracellular signaling pathways implicated in PCOS steroidogenesis and in androgen action have been studied, however, PCOS pathogenesis remains obscure. Growing evidence links androgens with pathophysiology of PCOS and metabolic derangements.

SUMMARY

Despite intensive investigation, etiology and underlying mechanisms of PCOS remain unclear, warranting further investigation. Better understanding of molecular and genetic basis might lead to invention of novel therapeutic approaches. Long-term interventional studies that lower androgen levels in women with hyperandrogenism might protect against metabolic and cardiovascular comorbidities are needed.