Androgen-responsive aspects of cognition in girls with Turner syndrome

The Changing Face of Turner Syndrome

Turner syndrome (TS) is a condition in females missing the second sex chromosome (45,X) or parts thereof. It is considered a rare genetic condition and is associated with a wide range of clinical stigmata, such as short stature, ovarian dysgenesis, delayed puberty and infertility, congenital malformations, endocrine disorders, including a range of autoimmune conditions and type 2 diabetes, and neurocognitive deficits. Morbidity and mortality are clearly increased compared with the general population and the average age at diagnosis is quite delayed. During recent years it has become clear that a multidisciplinary approach is necessary toward the patient with TS. A number of clinical advances has been implemented, and these are reviewed. Our understanding of the genomic architecture of TS is advancing rapidly, and these latest developments are reviewed and discussed. Several candidate genes, genomic pathways and mechanisms, including an altered transcriptome and epigenome, are also presented.

Women With Turner Syndrome Are Both Estrogen and Androgen Deficient: The Impact of Hormone Replacement Therapy

CONTEXT

Women with Turner syndrome (TS) suffer from hypergonadotropic hypogonadism, causing a deficit in gonadal hormone secretion. As a consequence, these women are treated with estrogen from the age of 12 years, and later in combination with progesterone. However, androgens have been given less attention.

OBJECTIVE

To assess sex hormone levels in women with TS, both those treated and those nontreated with hormone replacement therapy (HRT), and investigate the impact of HRT on sex hormone levels.

METHODS

At Aarhus University Hospital, 99 women with TS were followed 3 times from August 2003 to February 2010. Seventeen were lost during follow-up. Control group 1 consisted of 68 healthy age-matched control women seen once during this period. Control group 2 consisted of 28 young, eumenorrheic women sampled 9 times throughout the same menstrual cycle. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17β-estradiol, estrone sulfate, DHEAS, testosterone, free androgen index, androstenedione, 17-OH progesterone, and sex hormone-binding globulin (SHBG) were analyzed.

RESULTS

All androgens, 17-OH progesterone, and sex hormone-binding globulin (SHBG) were 30% to 50% lower in TS compared with controls (P < 0.01). FSH, LH, and estrone sulfate were more than doubled in women with TS compared with controls (P < 0.02). Using principal component analysis, we describe a positive correlation between women with TS receiving HRT, elevated levels of SHBG, and decreased levels of androgens.

CONCLUSION

The sex hormone profile in TS reveals a picture of androgen deficiency, aggravated further by HRT. Conventional HRT does not normalize estradiol levels in TS.

The contribution of Xp22.31 gene dosage to Turner and Klinefelter syndromes and sex-biased phenotypes

Turner syndrome (TS) is a rare developmental condition in females caused by complete, or partial, loss of the second sex chromosome; it is associated with a number of phenotypes including short stature, ovarian failure and infertility, as well as neurobehavioural and cognitive manifestations. In contrast, Klinefelter syndrome (KS) arises from an excess of X chromosome material in males (typical karyotype is 47,XXY); like TS, KS is associated with infertility and hormonal imbalance, and behavioural/neurocognitive differences from gonadal sex-matched counterparts. Lower dosage of genes that escape X-inactivation may partially explain TS phenotypes, whilst overdosage of these genes may contribute towards KS-related symptoms. Here, I discuss new findings from individuals with deletions or duplications limited to Xp22.31 (a region escaping X-inactivation), and consider the extent to which altered gene dosage within this small interval (and of the steroid sulfatase (STS) gene in particular) may influence the phenotypic profiles of TS and KS. The expression of X-escapees can be higher in female than male tissues; I conclude by considering how lower Xp22.31 gene dosage in males may increase their likelihood of exhibiting particular phenotypes relative to females. Understanding the genetic contribution to specific phenotypes in rare disorders such as TS and KS, and to more common sex-biased phenotypes, will be important for developing more effective, and more personalised, therapeutic approaches.

Oxandrolone for growth hormone-treated girls aged up to 18 years with Turner syndrome

BACKGROUND

The final adult height of untreated girls aged up to 18 years with Turner syndrome (TS) is approximately 20 cm shorter compared with healthy females. Treatment with growth hormone (GH) increases the adult height of people with TS. The effects of adding the androgen, oxandrolone, in addition to GH are unclear. Therefore, we conducted this systematic review to investigate the benefits and harms of oxandrolone as an adjuvant therapy for people with TS treated with GH.

OBJECTIVES

To assess the effects of oxandrolone on growth hormone-treated girls aged up to 18 years with Turner syndrome.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, the ICTRP Search Portal and ClinicalTrials.gov. The date of the last search was October 2018. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled clinical trials (RCTs) that enrolled girls aged up to 18 years with TS who were treated with GH and oxandrolone compared with GH only treatment.

DATA COLLECTION AND ANALYSIS

Three review authors independently screened titles and abstracts for relevance, selected trials, extracted data and assessed risk of bias. We resolved disagreements by consensus, or by consultation with a fourth review author. We assessed trials for overall certainty of the evidence using the GRADE instrument.

MAIN RESULTS

We included six trials with 498 participants with TS, 267 participants were randomised to oxandrolone plus GH treatment and 231 participants were randomised to GH only treatment. The individual trial sample size ranged between 22 and 133 participants. The included trials were conducted in 65 different paediatric endocrinology healthcare facilities including clinics, centres, hospitals and academia in the USA and Europe. The duration of interventions ranged between 3 and 7.6 years. The mean age of participants at start of therapy ranged from 9 to 12 years. Overall, we judged only one trial at low risk of bias in all domains and another trial at high risk of bias in most domains. We downgraded the level of evidence mainly because of imprecision (low number of trials, low number of participants or both). Comparing oxandrolone plus GH with GH only for final adult height showed a mean difference (MD) of 2.7 cm in favour of oxandrolone plus GH treatment (95% confidence interval (CI) 1.3 to 4.1; P < 0.001; 5 trials, 270 participants; moderate-quality evidence). The 95% prediction interval ranged between 0.3 cm and 5.1 cm. For adverse events, we based our main analysis on reliable date from two trials with overall low risk of bias. There was no evidence of a difference between oxandrolone plus GH and GH for adverse events (RR 1.81, 95% CI 0.83 to 3.96; P = 0.14; 2 trials, 170 participants; low-quality evidence). Six out of 86 (18.6%) participants receiving oxandrolone plus GH compared with 8/84 (9.5%) participants receiving GH only reported adverse events, mainly signs of virilisation (e.g. deepening of the voice). One trial each investigated the effects of treatments on speech (voice frequency; 88 participants), cognition (51 participants) and psychological status (106 participants). The overall results for these comparisons were inconclusive (very low-quality evidence). No trial reported on health-related quality of life or all-cause mortality.

AUTHORS' CONCLUSIONS

Addition of oxandrolone to the GH therapy led to a modest increase in the final adult height of girls aged up to 18 years with TS. Adverse effects identified included virilising effects such as deepening of the voice, but reporting was inadequate in some trials.

Clinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting

Turner syndrome affects 25-50 per 100,000 females and can involve multiple organs through all stages of life, necessitating multidisciplinary approach to care. Previous guidelines have highlighted this, but numerous important advances have been noted recently. These advances cover all specialty fields involved in the care of girls and women with TS. This paper is based on an international effort that started with exploratory meetings in 2014 in both Europe and the USA, and culminated with a Consensus Meeting held in Cincinnati, Ohio, USA in July 2016. Prior to this meeting, five groups each addressed important areas in TS care: 1) diagnostic and genetic issues, 2) growth and development during childhood and adolescence, 3) congenital and acquired cardiovascular disease, 4) transition and adult care, and 5) other comorbidities and neurocognitive issues. These groups produced proposals for the present guidelines. Additionally, four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with a separate systematic review of the literature. These four questions related to the efficacy and most optimal treatment of short stature, infertility, hypertension, and hormonal replacement therapy. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with The European Society for Pediatric Endocrinology, The Endocrine Society, European Society of Human Reproduction and Embryology, The American Heart Association, The Society for Endocrinology, and the European Society of Cardiology. The guideline has been formally endorsed by the European Society for Endocrinology, the Pediatric Endocrine Society, the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology and the Endocrine Society. Advocacy groups appointed representatives who participated in pre-meeting discussions and in the consensus meeting.

HRT for women with premature ovarian insufficiency: a comprehensive review

BACKGROUND

Premature ovarian insufficiency (POI), often and misleadingly referred to as ‘premature menopause’, is defined as a loss of ovarian activity before the age of 40 years and is characterized by irregular or absent periods and reduced fertility. Symptoms include those associated with the natural menopause (night sweats and vaginal dryness), and with the long-term adverse effects of estrogen deficiency (osteoporosis and cardiovascular disease): the latter is believed to explain the shorter life expectancy associated with POI.

OBJECTIVE AND RATIONALE

The objective of the current review was to collect all relevant studies supporting recommendations on the indications, treatment options, and risks of hormone replacement therapy (HRT) (estrogen, progestogens and androgens) for women with POI.

SEARCH METHODS

The current review was written based on the best available evidence on the topic collected for the recently published ESHRE guideline on the management of women with POI. PUBMED/MEDLINE and the Cochrane library were searched in a stepwise approach. Relevant references were summarized in evidence tables, with assessment of the quality.

OUTCOMES

HRT is strongly recommended for women with POI, mainly for vasomotor and genito-urinary symptom relief. In addition, HRT has been shown to have a role in bone protection and probably also in primary prevention of cardiovascular disease. There is little evidence on the optimal type, regimen and dose of HRT; patient preference for route and method of administration of each component of HRT must be considered when prescribing, as should contraceptive needs. In women with POI, physiological replacement of estrogen (and progesterone) is essential for their health, and the controversies that surround the use of HRT in postmenopausal women do not apply.

LIMITATIONS, REASONS FOR CAUTION

N/A.

WIDER IMPLICATIONS

New areas of study on HRT for women with POI should focus on life expectancy, quality of life and neurological function. Furthermore, randomized controlled trials comparing transdermal estradiol with oral estrogens with regard to efficacy, patient satisfaction and side effects are urgently needed.

STUDY FUNDING/COMPETING INTERESTS

The authors received no funding for the review. The costs for the development of the ESHRE guideline were covered by ESHRE. The authors have no conflicts of interest to disclose.

A meta-analysis of math performance in Turner syndrome

AIM

Studies investigating the relationship between Turner syndrome and math learning disability have used a wide variation of tasks designed to test various aspects of mathematical competencies. Although these studies have revealed much about the math deficits common to Turner syndrome, their diversity makes comparisons between individual studies difficult. As a result, the consistency of outcomes among these diverse measures remains unknown. The overarching aim of this review is to provide a systematic meta-analysis of the differences in math and number performance between females with Turner syndrome and age-matched neurotypical peers.

METHOD

We provide a meta-analysis of behavioral performance in Turner syndrome relative to age-matched neurotypical populations on assessments of math and number aptitude. In total, 112 comparisons collected across 17 studies were included.

RESULTS

Although 54% of all statistical comparisons in our analyses failed to reject the null hypothesis, our results indicate that meaningful group differences exist on all comparisons except those that do not require explicit calculation.

INTERPRETATION

Taken together, these results help elucidate our current understanding of math and number weaknesses in Turner syndrome, while highlighting specific topics that require further investigation.

Elucidating X chromosome influences on Attention Deficit Hyperactivity Disorder and executive function

OBJECTIVE

To identify distinct behavioral and cognitive profiles associated with ADHD in Turner syndrome (TS), relative to idiopathic ADHD and neurotypical controls, in order to elucidate X-linked influences contributing to ADHD.

METHODS

We used a multilevel-model approach to compare 49 girls with TS to 37 neurotypical females, aged 5-12, on established measures of behavior (BASC-2) and neurocognitive function (NEPSY). We further compared girls with TS to BASC-2 and NEPSY age-matched reference data obtained from children with idiopathic ADHD.

RESULTS

Within the TS group, 51% scored at or above the "at-risk" range for ADHD-associated behaviors on the BASC-2 (TS/+ADHD). The BASC-2 behavioral profile in this TS/+ADHD-subgroup was comparable to a reference group of boys with ADHD with respect to attentional problems and hyperactivity. However, the TS/+ADHD-subgroup had significantly higher hyperactivity scores relative to a reference sample of girls with ADHD (p = 0.016). The behavioral profile in TS was associated with significantly lower attention and executive function scores on the NEPSY relative to neurotypical controls (p = 0.015); but was comparable to scores from a reference sample of children with idiopathic ADHD. Deficits in attention and executive function were not observed in girls with TS having low levels of ADHD-associated behavior (TS/-ADHD).

CONCLUSIONS

ADHD-associated behavioral and cognitive problems in TS are prevalent and comparable in severity to those found in children with idiopathic ADHD. The ADHD phenotype in TS also appears relatively independent of cognitive features typically associated with TS, like visuospatial weaknesses. These findings suggest that X-linked haploinsufficiency and downstream biological effects contribute to increased risk for ADHD.

Effect of oxandrolone therapy on adult height in Turner syndrome patients treated with growth hormone: a meta-analysis

Turner syndrome is a chromosomal abnormality in which there is complete or partial absence of the X chromosome. Turner syndrome effects 1 in every 2000 live births. Short stature is a cardinal feature of Turner Syndrome and the standard treatment is recombinant human growth hormone. When growth hormone is started at an early age a normal adult height can be achieved. With delayed diagnosis young women with Turner Syndrome may not reach a normal height. Adjuvant therapy with oxandrolone is used but there is no consensus on the optimal timing of treatment, the duration of treatment and the long term adverse effects of treatment. The objective of this review and meta-analysis is to examine the effect of oxandrolone on adult height in growth hormone treated Turner syndrome patients. Eligible trials were identified by a literature search using the terms: Turner syndrome, oxandrolone. The search was limited to English language randomized-controlled trials after 1980. Twenty-six articles were reviewed and four were included in the meta-analysis. A random effects model was used to calculate an effect size and confidence interval. The pooled effect size of 2.0759 (95 % CI 0.0988 to 4.0529) indicates that oxandrolone has a positive effect on adult height in Turner syndrome when combined with growth hormone therapy. In conclusion, the addition of oxandrolone to growth hormone therapy for treatment of short stature in Turner syndrome improves adult height. Further studies are warranted to investigate if there is a subset of Turner syndrome patients that would benefit most from growth hormone plus oxandrolone therapy, and to determine the optimal timing and duration of such therapy.

Novel approaches to short stature therapy

Besides growth hormone, several pharmaceutical products have been investigated for efficacy and safety in increasing short term growth or adult height. Short-term treatment with testosterone esters in boys with constitutional delay of growth and puberty is efficacious in generating secondary sex characteristics and growth acceleration. The addition of oxandrolone to growth hormone (GH) in Turner syndrome has an additive effect on adult height gain. Treatment with GnRH analogs is the established treatment of central precocious puberty, and its addition to GH therapy appears effective in increasing adult height in GH deficient children, and possibly short children born SGA or with SHOX deficiency, who are still short at pubertal onset. Aromatase inhibitors appear effective in several rare disorders, but their value in increasing adult height in early pubertal boys with GH deficiency or idiopathic short stature is uncertain. A trial with a C-natriuretic peptide analog offers hope for children with achondroplasia.

Long-term effects of oxandrolone treatment in childhood on neurocognition, quality of life and social-emotional functioning in young adults with Turner syndrome

Turner syndrome (TS) is the result of (partial) absence of one X-chromosome. Besides short stature, gonadal dysgenesis and other physical aspects, TS women have typical psychological features. Since psychological effects of androgen exposure in childhood probably are long-lasting, we explored long-term psychological functioning after oxandrolone (Ox) therapy during childhood in adults with TS in terms of neurocognition, quality of life and social-emotional functioning. During the initial study, girls were treated with growth hormone (GH) combined with placebo (Pl), Ox 0.03 mg/kg/day, or Ox 0.06 mg/kg/day from the age of eight, and estrogen from the age of twelve. Sixty-eight women participated in the current double-blinded follow-up study (mean age 24.0 years, mean time since stopping GH/Ox 8.7 years). We found no effects on neurocognition. Concerning quality of life women treated with Ox had higher anxiety levels (STAI 37.4 ± 8.4 vs 31.8 ± 5.0, p=0.002) and higher scores on the depression subscale of the SCL-90-R (25.7 ± 10.7 vs 20.5 ± 4.7, p=0.01). Regarding social-emotional functioning, emotion perception for fearful faces was lower in the Ox-treated patients, without effect on interpersonal behavior. Our exploratory study is the first to suggest that androgen treatment in adolescence possibly has long-term effects on adult quality of life and social-emotional functioning. However, differences are small and clinical implications of our results seem limited. Therefore we would not recommend against the use of Ox in light of psychological consequences.

Sex differences in attention Deficit Hyperactivity Disorder: candidate genetic and endocrine mechanisms

Attention Deficit Hyperactivity Disorder (ADHD) is a developmental condition characterised by severe inattention, pathological impulsivity and hyperactivity; it is relatively common affecting up to 6% of children, and is associated with a risk of long-term adverse educational and social consequences. Males are considerably more likely to be diagnosed with ADHD than females; the course of the disorder and its associated co-morbidities also appear to be sensitive to sex. Here, I discuss fundamental biological (genetic and endocrine) mechanisms that have been shown to, or could theoretically, contribute towards these sexually dimorphic phenomena. Greater understanding of how and why the sexes differ with respect to ADHD vulnerability should allow us to identify and characterise novel protective and risk factors for the disorder, and should ultimately facilitate improved diagnosis, prognosis and treatment.

Cognitive effects of cancer and its treatments at the intersection of aging: what do we know; what do we need to know?

There is a fairly consistent, albeit non-universal body of research documenting cognitive declines after cancer and its treatments. While few of these studies have included subjects aged 65 years and older, it is logical to expect that older patients are at risk of cognitive decline. Here, we use breast cancer as an exemplar disease for inquiry into the intersection of aging and cognitive effects of cancer and its therapies. There are a striking number of common underlying potential biological risks and pathways for the development of cancer, cancer-related cognitive declines, and aging processes, including the development of a frail phenotype. Candidate shared pathways include changes in hormonal milieu, inflammation, oxidative stress, DNA damage and compromised DNA repair, genetic susceptibility, decreased brain blood flow or disruption of the blood-brain barrier, direct neurotoxicity, decreased telomere length, and cell senescence. There also are similar structure and functional changes seen in brain imaging studies of cancer patients and those seen with "normal" aging and Alzheimer's disease. Disentangling the role of these overlapping processes is difficult since they require aged animal models and large samples of older human subjects. From what we do know, frailty and its low cognitive reserve seem to be a clinically useful marker of risk for cognitive decline after cancer and its treatments. This and other results from this review suggest the value of geriatric assessments to identify older patients at the highest risk of cognitive decline. Further research is needed to understand the interactions between aging, genetic predisposition, lifestyle factors, and frailty phenotypes to best identify the subgroups of older patients at greatest risk for decline and to develop behavioral and pharmacological interventions targeting this group. We recommend that basic science and population trials be developed specifically for older hosts with intermediate endpoints of relevance to this group, including cognitive function and trajectories of frailty. Clinicians and their older patients can advance the field by active encouragement of and participation in research designed to improve the care and outcomes of the growing population of older cancer patients.

Interactions between opioids and anabolic androgenic steroids: implications for the development of addictive behavior

Over the past decades, research on doping agents, such as anabolic androgenic steroids (AAS), has revealed that these compounds are often used in combination with other drugs of abuse. It seems that misuse of AAS probably involves more than a desire to enhance appearance or sports performance and studies have revealed that steroids are commonly connected with alcohol, opioids, tobacco, and psychotropic drugs. We have observed that AAS may interact with the endogenous opioids, excitatory amino acids, and dopaminergic pathways involved in the brain reward system. Furthermore, our studies provide evidence that AAS may induce an imbalance in these signal systems leading to an increased sensitivity toward opioid narcotics and central stimulants. In fact, studies performed in various clinics have shown that individuals taking AAS are likely to get addicted to opioids like heroin. This chapter reviews current knowledge on interactions between AAS and endogenous as well as exogenous opioids based not only on research in our laboratory but also on research carried out by several other clinical and preclinical investigators.

Vulnerability for autism traits in boys and men with an extra X chromosome (47,XXY): the mediating role of cognitive flexibility

The XXY chromosomal pattern (Klinefelter syndrome, KS) has been associated with specific effects on physical, neurobiological, endocrinological and psychological development. This study was focused on the described risk for autism in KS, and the cognitive mechanisms that mediate this risk. Our aim was to assess whether autistic features in KS result from impairments in executive functioning, more specifically difficulties in cognitive flexibility. In total, 71 boys and men with KS and 61 non-clinical controls participated in the study. Autistic features were assessed using the Autism-spectrum Quotient (AQ). Mental flexibility was measured using the Wisconsin Card Sorting Test (WCST). The level of autism traits was significantly increased in the KS group, the effect size for total AQ score was 1.6. The KS group also showed significantly more difficulties in cognitive flexibility, as indicated by and increased number of perseverative (but not non-perseverative) errors in the WCST. This effect was independent of intellectual functioning, age or testosterone supplements. Within the KS group, the number of perseverative errors was significantly (positively) correlated with total AQ score. Our findings suggest that KS can be associated with dysfunctions in mental flexibility, and that individuals with more mental flexibility problems also have more autism traits. This insight is relevant for diagnosis, prevention and treatment of severe problems in individuals with KS. Implications also extend beyond this specific syndrome. As executive dysfunctions in KS have also been linked to ADHD symptoms and thought disorder, this could be a shared mechanism contributing to overlap in symptoms and comorbidity between different psychiatric conditions.

Sex hormone replacement in Turner syndrome

The cardinal features of Turner syndrome (TS) are short stature, congenital abnormalities, infertility due to gonadal dysgenesis, with sex hormone insufficiency ensuing from premature ovarian failure, which is involved in lack of proper development of secondary sex characteristics and the frequent osteoporosis seen in Turner syndrome. But sex hormone insufficiency is also involved in the increased cardiovascular risk, state of physical fitness, insulin resistance, body composition, and may play a role in the increased incidence of autoimmunity. Severe morbidity and mortality affects females with Turner syndrome. Recent research emphasizes the need for proper sex hormone replacement therapy (HRT) during the entire lifespan of females with TS and new hypotheses concerning estrogen receptors, genetics and the timing of HRT offers valuable new information. In this review, we will discuss the effects of estrogen and androgen insufficiency as well as the effects of sex HRT on morbidity and mortality with special emphasis on evidence based research and areas needing further studies.

Turner syndrome and sexual differentiation of the brain: implications for understanding male-biased neurodevelopmental disorders

Turner syndrome (TS) is one of the most common sex chromosome abnormalities. Affected individuals often show a unique pattern of cognitive strengths and weaknesses and are at increased risk for a number of other neurodevelopmental conditions, many of which are more common in typical males than typical females (e.g., autism and attention-deficit hyperactivity disorder). This phenotype may reflect gonadal steroid deficiency, haploinsufficiency of X chromosome genes, failure to express parentally imprinted genes, and the uncovering of X chromosome mutations. Understanding the contribution of these different mechanisms to outcome has the potential to improve clinical care for individuals with TS and to better our understanding of the differential vulnerability to and expression of neurodevelopmental disorders in males and females. In this paper, we review what is currently known about cognition and brain development in individuals with TS, discuss underlying mechanisms and their relevance to understanding male-biased neurodevelopmental conditions, and suggest directions for future research.

Reduced sebum production in Turner syndrome: a study of twenty-two patients

Turner's syndrome (TS) is a genetic disorder caused by numeric and/or structural abnormalities of the X chromosome. In a previous study it was observed that acne is less frequent in TS than in the general population. Since the onset of acne in pre-pubertal or pubertal age is related to sebum production, this study evaluates sebum secretion in TS patients, comparing the results with those of a control group of age-matched healthy female subjects. A total of 22 patients affected by TS (mean age 26.56±7.89 years) and a control group of 23 age-matched healthy females were studied. Sebum production was measured using a Sebumeter SM810. Mean sebum secretion in TS subjects was significantly lower than in the control group (81.35±66.44 UA vs 147.09±33.62 UA, p<0.001) and this significant difference was found in every facial zone. The reduction of sebum secretion may explain, using a simple and non-invasive method, the absence or the low incidence of acne in TS patients.

Salivary testosterone does not predict mental rotation performance in men or women

Multiple studies report relationships between circulating androgens and performance on sexually differentiated spatial cognitive tasks in human adults, yet other studies find no such relationships. Relatively small sample sizes are a likely source of some of these discrepancies. The present study thus tests for activational effects of testosterone (T) using a within-participants design by examining relationships between diurnal fluctuations in salivary T and performance on a male-biased spatial cognitive task (Mental Rotation Task) in the largest sample yet collected: 160 women and 177 men. T concentrations were unrelated to within-sex variation in mental rotation performance in both sexes. Further, between-session learning-related changes in performance were unrelated to T levels, and circadian changes in T were unrelated to changes in spatial performance in either sex. These results suggest that circulating T does not contribute substantially to sex differences in spatial ability in young men and women. By elimination, the contribution of androgens to sex differences in human performance on these tasks may be limited to earlier, organizational periods.

Cognitive profile of Turner syndrome

Turner syndrome (TS) is a relatively common neurogenetic disorder characterized by complete or partial monosomy-X in a phenotypic female. TS is associated with a cognitive profile that typically includes intact intellectual function and verbal abilities with relative weaknesses in visual-spatial, executive, and social cognitive domains. In this report, we review previous and current research related to the cognitive profile of TS. We also discuss how cognitive impairments in this syndrome may reflect integrative rather than modular deficits. For example, the less commonly reported areas of verbal difficulty in TS and certain visual-spatial deficits seem significantly influenced by impairments in executive function and spatially loaded stimuli. We provide a summary of cognitive testing measures used in the assessment of visual-spatial and executive skills, which includes test domain descriptions as well as a comprehensive examination of social cognitive function in TS. This review concludes with a discussion of ecological interpretations regarding the meaning of cognitive deficits in TS at the individual level.

Androgen replacement therapy in Turner syndrome: a pilot study

CONTEXT

Women with Turner syndrome (TS) have reduced levels of androgens due to ovarian failure.

HYPOTHESES

Morbidity associated with TS, such as bone fragility, metabolic changes, obesity, neurocognitive profile, and sexual problems may partly relate to androgen insufficiency and improve on androgen replacement therapy (ART).

OBJECTIVES

The objective of the study was to determine the effect of androgens on morbidity in TS.

DESIGN

Fourteen TS women (aged 17-27 yr) participated in a randomized, double-blind, placebo-controlled crossover pilot. The study was conducted in a hospital outpatient clinic between December 2001 and July 2004.

INTERVENTION

TS patients were on estrogen/progestin replacement therapy. Subjects received oral 1.5 mg methyl testosterone (ART) or placebo for 1 yr and the alternative for another year.

MAIN OUTCOME MEASURES

The study compared body composition as a primary outcome, and physiology, biochemistry, visceral fat, cognition, and quality of life (QOL) as secondary outcomes.

RESULTS

ART as compared with placebo reduced total cholesterol, triglycerides, and high-density lipoprotein cholesterol. It improved bone mineral density, increased lean body mass, and decreased fat mass. ART improved attention, reaction time, and verbal memory and had no effect on executive functions and spatial cognition. Patients reported improved QOL, including general health, coping with stress, and sexual desire.

CONCLUSIONS

Androgen insufficiency plays a role in TS-impaired body composition, neurocognition, and QOL, and these aspects improve with ART, which was safe and effective when given for 1 yr.

Effects of treatment with oxandrolone for 4 years on the frequency of severe arithmetic learning disability in girls with Turner syndrome

OBJECTIVES

To study androgen treatment effects on arithmetic performance in girls with Turner syndrome.

STUDY DESIGN

Forty-four girls, ages 10 to 14 years at baseline, completed 4 years of treatment with oxandrolone (Ox) or placebo (Pl). All received growth hormone and estrogen replacement therapy. We assessed the number of girls with severe learning disability (LD, standard score <or=5(th) percentile) on measures of academic arithmetic and reading achievement (WRAT-3, arithmetic and reading), given yearly, and the WIAT numerical operations (NOS) and reading subtests, given at year 4.

RESULTS

On the WRAT-3 arithmetic, the frequency of severe arithmetic LD was similar in the Ox and Pl groups at baseline and at years 1 and 2. At years 3 and 4, fewer girls in the Ox than Pl group had a severe arithmetic LD (year 4: 0/22 vs 5/21, P = .02). On the WIAT NOS (year 4), fewer girls in the Ox than Pl groups had a severe arithmetic LD (3/21 vs 8/20, P = .09). WIAT NOS error analysis suggested that the improved performance in the Ox group was associated with better performance on multiplication and division (P < .01). The frequency of severe LD for the WRAT-3 reading was similar for the Ox and Pl groups (all years) and for the WIAT reading subtest (year 4).

CONCLUSIONS

Androgen treatment for 4 years in girls with Turner syndrome resulted in a small decrease in frequency of severe arithmetic LD, with no effect on reading LD.

Cognitive mechanisms underlying disorganization of thought in a genetic syndrome (47,XXY)

Because of the risk for development of psychopathology such as psychotic symptoms, it has been suggested that studying men with the XXY karyotype may help in the search for underlying cognitive, neural and genetic mechanisms. The aim of this study was to identify cognitive mechanisms that may contribute to disorganization of thought in XXY men. A group of 24 XXY men and two non-clinical control groups (N=20, N=18) participated in the study. The level of disorganization of thought was measured using the Schizotypal Personality Questionnaire. We assessed IQ, lateralization of verbal information processing and executive functions including inhibition and mental flexibility. XXY men with high levels of disorganization showed more severe impairments in mental flexibility and inhibition as compared to non-clinical controls and other XXY men. This subgroup also showed a stronger reduction in lateralization of verbal information processing. IQ measures did not differentiate XXY men with high versus low levels of disorganization. These findings indicate that executive impairments in the domains of inhibition and mental flexibility might play a role in the increased vulnerability for disorganized thought in the XXY group. Reduced lateralization of verbal information processing points to non-optimal cerebral specialization in the XXY group, especially in XXY men with high levels of disorganization. This fits with deficits in brain functions most vulnerable to such maturational disruptions, i.e. executive dysfunctions. Our findings are in line with those reported for schizophrenia patients with thought disorder. We speculate that the underlying mechanisms of thought disorder probably are deficit specific rather than disorder specific.

Vulnerabilidad social en el síndrome de turner: interacción genes-ambiente

En este trabajo se exponen los fundamentos teóricos que permiten considerar al Síndrome de Turner como un “modelo genético sensible” en el cual analizar asociaciones entre caracteres psicológicos y factores genéticos y ambientales. La investigación en esta línea permitiría dilucidar mecanismos de riesgo ambiental y comprender el grado de “vulnerabilidad” que presentan las mujeres con el síndrome. El Síndrome de Turner es un trastorno genético, no heredable, que se caracteriza por la deleción total o parcial del cromosoma X en el sexo femenino. El estudio de la disfunción social que presentan las mujeres con este síndrome, es decir, de la capacidad para relacionarse con el entorno y la calidad de los vínculos tiene importantes implicaciones en la comprensión de la forma en que actúa el ambiente sobre el desarrollo psicológico, y de cómo a su vez éste se ve afectado por factores genéticos que actúan en interacción.

Paternal X could relate to arithmetic function; study of cognitive function and parental origin of X chromosome in Turner syndrome

BACKGROUND

45,X Turner syndrome (TS) female subjects have visuospatial skill and social cognition deficits that may arise from X-linked imprinting. The aim of the present study was to compare phenotypic characteristics and neurocognitive pattern of 12 monosomic TS girls, according to X-linked imprinting.

METHODS

Microsatellite markers were used to determine the parental origin of the missing chromosome X. Wechsler Intelligence Scale for Children-Revised (WISC-R) was administered as measures of general intellectual functioning. The results were compared in TS patients with maternally derived X chromosome (Xm) and paternally derived X chromosome (Xp).

RESULTS

Six out of 12 patients (50%) had Xm, and the other six (50%) had Xp chromosome. There was no difference in the total, verbal and performance IQ score between the TS subgroups with Xm and Xp. When the WISC-R subtest score patterns were compared, the mean arithmetic scores were significantly poorer in the Xm TS than in the Xp TS.

CONCLUSION

In monosomic TS cases, paternal imprinting may predict arithmetic ability, on the other hand, reductionist consideration defined by genetic imprinting is not sufficient to confirm this. Further studies should be undertaken to clarify this situation.

Turner Syndrome

Turner syndrome is a neurogenetic disorder characterized by partial or complete monosomy-X. It is associated with certain physical and medical features, including estrogen deficiency, short stature, and increased risk for several diseases, with cardiac conditions being among the most serious. The cognitive-behavioral phenotype associated with the syndrome includes strengths in verbal domains with impairments in visuospatial, executive function, and emotion processing. Less is known regarding psychosocial and psychiatric functioning in Turner syndrome, but essential aspects of psychotherapeutic treatment plans are suggested. Future investigations should include continued genetic studies and determination of candidate genes for physical and cognitive features. Multimodal, interdisciplinary studies are essential for identifying optimal, syndrome-specific interventions for improving the lives of individuals who have Turner syndrome.

A Turner syndrome neurocognitive phenotype maps to Xp22.3

BACKGROUND

Turner syndrome (TS) is associated with a neurocognitive phenotype that includes selective nonverbal deficits, e.g., impaired visual-spatial abilities. We previously reported evidence that this phenotype results from haploinsufficiency of one or more genes on distal Xp. This inference was based on genotype/phenotype comparisons of individual girls and women with partial Xp deletions, with the neurocognitive phenotype considered a dichotomous trait. We sought to confirm our findings in a large cohort (n = 47) of adult women with partial deletions of Xp or Xq, enriched for subjects with distal Xp deletions.

METHODS

Subjects were recruited from North American genetics and endocrinology clinics. Phenotype assessment included measures of stature, ovarian function, and detailed neurocognitive testing. The neurocognitive phenotype was measured as a quantitative trait, the Turner Syndrome Cognitive Summary (TSCS) score, derived from discriminant function analysis. Genetic analysis included karyotyping, X inactivation studies, fluorescent in situ hybridization, microsatellite marker genotyping, and array comparative genomic hybridization.

RESULTS

We report statistical evidence that deletion of Xp22.3, an interval containing 31 annotated genes, is sufficient to cause the neurocognitive phenotype described by the TSCS score. Two other cardinal TS features, ovarian failure and short stature, as well as X chromosome inactivation pattern and subject's age, were unrelated to the TSCS score.

CONCLUSION

Detailed mapping suggests that haploinsufficiency of one or more genes in Xp22.3, the distal 8.3 megabases (Mb) of the X chromosome, is responsible for a TS neurocognitive phenotype. This interval includes the 2.6 Mb Xp-Yp pseudoautosomal region (PAR1). Haploinsufficiency of the short stature gene SHOX in PAR1 probably does not cause this TS neurocognitive phenotype. Two genes proximal to PAR1 within the 8.3 Mb critical region, STS and NLGN4X, are attractive candidates for this neurocognitive phenotype.

Testosterone levels and cognitive functioning in women with polycystic ovary syndrome and in healthy young women

We investigated the possible influence of testosterone (T) on cognitive functioning in women with polycystic ovary syndrome (PCOS), an endocrine disorder associated with elevated levels of free testosterone (free T). Performance on a battery of neuropsychological tests in 29 women with elevated free T levels due to PCOS was compared to the performance of 22 age- and education-matched, healthy control women with free T levels in the normal female range. Women with PCOS had significantly higher levels of free T (estimated by the free androgen index) and demonstrated significantly worse performance on tests of verbal fluency, verbal memory, manual dexterity, and visuospatial working memory than the healthy control women. No differences between the groups were found on tests of mental rotation, spatial visualization, spatial perception, or perceptual speed. These results suggest that, in women, elevations in free T may be associated with poorer performance on cognitive tasks that tend to show a female advantage.

Influence of X chromosome and hormones on human brain development: a magnetic resonance imaging and proton magnetic resonance spectroscopy study of Turner syndrome

BACKGROUND

Women with Turner syndrome (TS; 45,X) lack a normal second X chromosome, and many are prescribed exogenous sex and growth hormones (GH). Hence, they allow us an opportunity to investigate genetic and endocrine influences on brain development.

METHODS

We examined brain anatomy and metabolism in 27 adult monosomic TS women and 21 control subjects with volumetric magnetic resonance imaging and magnetic resonance spectroscopy.

RESULTS

In TS women, regional gray matter volume was significantly smaller in parieto-occipital cortex and caudate nucleus and larger in cerebellar hemispheres. White matter was reduced in the cerebellar hemispheres, parieto-occipital regions, and splenium of the corpus callosum but was increased in the temporal and orbitofrontal lobes and genui of corpus callosum. Women with TS had a significantly lower parietal lobe concentration of N-acetyl aspartate, and higher hippocampal choline. Also, among women with TS, there were significant differences in regional gray matter volumes and/or neuronal integrity, depending upon parental origin of X chromosome and oxandrolone and GH use.

CONCLUSIONS

X chromosome monosomy, imprinting and neuroendocrine milieu modulate human brain development-perhaps in a regionally specific manner.

Cognition and the sex chromosomes: studies in Turner syndrome

Turner syndrome (TS) is a human genetic disorder involving females who lack all or part of one X chromosome. The complex phenotype includes ovarian failure, a characteristic neurocognitive profile and typical physical features. TS features are associated not only with complete monosomy X but also with partial deletions of either the short (Xp) or long (Xq) arm (partial monosomy X). Impaired visual-spatial/perceptual abilities are characteristic of TS children and adults of varying races and socioeconomic status, but global developmental delay is uncommon. The cognitive phenotype generally includes normal verbal function with relatively impaired visual-spatial ability, attention, working memory, and spatially dependent executive function. The constellation of neurocognitive deficits observed in TS is most likely multifactorial and related to a complex interaction between genetic abnormalities and hormonal deficiencies. Furthermore, other determinants, including an additional genetic mechanism, imprinting, may also contribute to cognitive deficits associated with monosomy X. As a relatively common genetic disorder with well-defined manifestations, TS presents an opportunity to investigate genetic and hormonal factors that influence female cognitive development. TS is an excellent model for such studies because of its prevalence, the well-characterized phenotype, and the wealth of molecular resources available for the X chromosome. In the current review, we summarize the hormonal and genetic factors that may contribute to the TS neurocognitive phenotype. The hormonal determinants of cognition in TS are related to estrogen and androgen deficiency. Our genetic hypothesis is that haploinsufficiency for gene/genes on the short arm of the X chromosome (Xp) is responsible for the hallmark features of the TS cognitive phenotype. Careful clinical and molecular characterization of adult subjects missing part of Xp links the TS phenotype of impaired visual spatial/perceptual ability to specific distal Xp chromosome regions. We demonstrate that small, nonmosaic deletion of the distal short arm of the X chromosome in adult women is associated with the same hallmark cognitive profile seen in adult women with TS. Future studies will elucidate the cognitive deficits and the underlying etiology. These results should allow us to begin to design cognitive interventions that might lessen those deficits in the TS population.

Androgen therapy in women

Androgens in women either derive from direct ovarian production or from peripheral conversion of the adrenal sex steroid precursor, dehydroepiandrosterone, towards active androgens. Therefore, loss of adrenal or ovarian function, caused by Addison's disease or consequent to bilateral oophorectomy, results in severe androgen deficiency, clinically often associated with a loss of libido and energy. Importantly, physiological menopause does not necessarily lead to androgen deficiency, as androgen synthesis in the ovaries may persist despite the decline in estrogen production. However, the definition of female androgen deficiency, as recently provided by the Princeton consensus statement, is not precise enough and may lead to over-diagnosis due to the high prevalence of its diagnostic criteria: androgen levels below or within the lower quartile of the normal range and concurrent sexual dysfunction. Importantly, physiological menopause is not necessarily associated with androgen deficiency and therefore does not routinely require androgen therapy. Current replacement options include transdermal testosterone administration or dehydroepiandrosterone treatment, both of which have been shown to result in significant improvements, in particular in libido and mood, while effects on body composition and muscular function are not well documented. It is important to keep in mind that the number of randomized controlled trials is still limited and that currently none of the available preparations is officially approved for use in women. Currently, androgen replacement should be reserved for women with severe androgen deficiency due to an established cause and matching clinical signs and symptoms.

Turner syndrome in adulthood

Turner syndrome is a common genetic disorder associated with abnormalities of the X chromosome and occurs in about 50 per 100,000 liveborn girls. It is associated with reduced adult height, gonadal dysgenesis and thus insufficient circulating levels of female sex steroids and infertility. Morbidity and mortality are increased throughout the lifespan. The average intellectual performance is within the normal range. A number of recent clinical studies have given new insight particularly into the adult phase of Turner syndrome. Treatment with growth hormone during childhood and adolescence enables a considerable gain in adult height. In most cases puberty has to be induced and female sex hormone replacement therapy is given during adulthood. Type 2 diabetes is often seen, and hypertension and associated cardiovascular disorders are frequent. The proper treatments of these disorders have not been firmly established. Since the risk of cardiovascular and endocrinological disease is clearly elevated, proper care during adulthood is crucial. Cognition and social functioning are altered in Turner syndrome.

Expression of SHOX in human fetal and childhood growth plate

Abnormalities in the growth plate may lead to short stature and skeletal deformity including Leri Weil syndrome, which has been shown to result from deletions or mutations in the SHOX gene, a homeobox gene located at the pseudoautosomal region of the X and Y chromosome. We studied the expression of SHOX protein, by immunohistochemistry, in human fetal and childhood growth plates and mRNA by in situ hybridization in childhood normal and Leri Weil growth plate. SHOX protein was found in reserve, proliferative, and hypertrophic zones of fetal growth plate from 12 wk to term and childhood control and Leri Weil growth plates. The pattern of immunostaining in the proliferative zone of childhood growth plate was patchy, with more intense uniform immunostaining in the hypertrophic zone. In situ hybridization studies of childhood growth plate demonstrated SHOX mRNA expression throughout the growth plate. No difference in the pattern of SHOX protein or mRNA expression was seen between the control and Leri Weil growth plate. These findings suggest that SHOX plays a role in chondrocyte function in the growth plate.

Serum androgen bioactivity in adolescence: a longitudinal study of boys with constitutional delay of puberty

We have examined the relationship between serum androgen bioactivity, as measured with a recombinant cell bioassay, and progression of puberty in 14 boys with constitutional delay of puberty. Six boys were followed up without treatment (control group), and eight boys received low-dose (1 mg/kg) testosterone enanthate im for 0-6 months together with an aromatase inhibitor, letrozole, 2.5 mg orally once a day for 0-12 months (treatment group). In the control group, serum androgen bioactivity increased during the course of puberty (P < 0.001). During 0-12 months of the study, the boys in the treatment group had higher androgen bioactivity levels (P < 0.05) and faster rate of pubic hair growth than the control boys (P < 0.05). Overall, the average serum androgen bioactivity during 12 months of follow-up correlated strongly with the concomitant changes in Tanner genital (r(S) = 0.89; n = 13; P < 0.005) and pubic hair stages (r(S) = 0.79; n = 13; P < 0.01). In conclusion, our results suggest that circulating androgen bioactivity mediates the tempo of pubertal maturation and that the combination of testosterone and letrozole given to boys with constitutional delay of puberty accelerates puberty.

Androgens increase spine synapse density in the CA1 hippocampal subfield of ovariectomized female rats

The effects of androgen on the density of spine synapses on pyramidal neurons in the CA1 area of the hippocampus were studied in ovariectomized (OVX) adult female rats. Treatment of OVX rats with testosterone propionate (TP; 500 microg/d, s.c., 2 d) significantly increased spine synapse density (from 0.661 +/- 0.016 spine synapse/microm3 in OVX rats to 1.081 +/- 0.018 spine synapse/microm3 after TP treatment). A smaller, but still statistically significant, increase in synapse density (0.955 +/- 0.029 spine synapse/microm3) was observed in OVX animals after treatment with the nonaromatizable androgen dihydrotestosterone (DHT; 500 microg/d, s.c., 2 d). Administration of 1 mg of letrozole, a powerful nonsteroidal aromatase inhibitor, 1 hr before the steroid injections almost completely blocked the synaptic response to testosterone, resulting in a mean synapse density (0.723 +/- 0.003 spine synapse/microm3) only slightly higher than in OVX control rats. By contrast, the response to DHT was unaffected by letrozole pretreatment. These data suggest that androgen secretion during the female reproductive cycle may contribute to cyclical changes in hippocampal synaptic density. They also indicate that androgen treatment may be as effective as estrogen replacement in reversing the decline in hippocampal CA1 spine synapses that follows loss of ovarian function. Induction of hippocampal synapse formation by androgen is not mediated entirely via intracerebral estrogen biosynthesis, however, because aromatase-independent mechanisms also significantly affect CA1 spine synapse density.

A review of neuropsychological and motor studies in Turner Syndrome

We reviewed the literature on Turner Syndrome (TS) from 1962 until March 2003 with respect to the following questions: Is there a consistent pattern of cognitive and/or motor dysfunction in TS girls and if so, is there an explanation for the disturbance? Many studies indicate that girls with TS have a disharmonic IQ profile: a verbal IQ that seems to be at a (nearly) normal level and a decreased PIQ. This profile remains into adulthood. Visual-spatial problems are mentioned most frequently and there is some evidence for a relationship to particular neuro-anatomical structures, hormonal dysfunction, and genotype. Although much less research has been done on motor performance in TS, there is clear evidence that it is disturbed too in TS. Many authors emphasize the interaction between somatic, psychological and social factors, but we did not find a clear theoretical framework explaining this relationship. We argue that there may be two independent problems: a visuospatial and a motor deficit possible related to specific genotypes and both have implications for functioning in daily life.

Management of the androgen-deficient woman

Active androgens in women either derive from direct ovarian production or from peripheral synthesis via downstream conversion of the adrenal sex steroid precursor dehydroepiandrosterone (DHEA). Significant androgen deficiency is present in adrenal and/or gonadal failure (e.g., due to Addison's disease, hypopituitarism, premature ovarian failure, or chronic glucocorticoid therapy). Androgen replacement in these women may result in significant improvements with regard to libido, mood, and bone mineral density. However, choosing both a convenient and efficient mode of androgen administration currently remains a challenge. Androgen levels do not necessarily change during physiological menopause, and the so-called female androgen deficiency syndrome (FADS) still awaits precise definition. Thus, androgen replacement should not be routinely considered in postmenopausal women but should be reserved for women with established androgen deficiency and related symptoms.