Variations in estrogen receptor alpha gene and risk of dementia, and brain volumes on MRI

Comorbidity of osteoporosis and Alzheimer's disease: Is `AKT `-ing on cellular glucose uptake the missing link?

Osteoporosis and Alzheimer's disease (AD) are both degenerative diseases. Osteoporosis often proceeds cognitive deficits, and multiple studies have revealed common triggers that lead to energy deficits in brain and bone. Risk factors for osteoporosis and AD, such as obesity, type 2 diabetes, aging, chemotherapy, vitamin deficiency, alcohol abuse, and apolipoprotein Eε4 and/or Il-6 gene variants, reduce cellular glucose uptake, and protective factors, such as estrogen, insulin, exercise, mammalian target of rapamycin inhibitors, hydrogen sulfide, and most phytochemicals, increase uptake. Glucose uptake is a fine-tuned process that depends on an abundance of glucose transporters (Gluts) on the cell surface. Gluts are stored in vesicles under the plasma membrane, and protective factors cause these vesicles to fuse with the membrane, resulting in presentation of Gluts on the cell surface. This translocation depends mainly on AKT kinase signaling and can be affected by a range of factors. Reduced AKT kinase signaling results in intracellular glucose deprivation, which causes endoplasmic reticulum stress and iron depletion, leading to activation of HIF-1α, the transcription factor necessary for higher Glut expression. The link between diseases and aging is a topic of growing interest. Here, we show that diseases that affect the same biochemical pathways tend to co-occur, which may explain why osteoporosis and/or diabetes are often associated with AD.

Effects of Sex Steroids in the Human Brain

Sex steroids are thought to play a critical developmental role in shaping both cortical and subcortical structures in the human brain. Periods of profound changes in sex steroids invariably coincide with the onset of sex differences in mental health vulnerability, highlighting the importance of sex steroids in determining sexual differentiation of the brain. Yet, most of the evidence for the central effects of sex steroids relies on non-human studies, as several challenges have limited our understanding of these effects in humans: the lack of systematic assessment of the human sex steroid metabolome, the different developmental trajectories of specific sex steroids, the impact of genetic variation and epigenetic changes, and the plethora of interactions between sex steroids, sex chromosomes, neurotransmitters, and other hormonal systems. Here we review how multimodal strategies may be employed to bridge the gap between the basic and clinical understanding of sex steroid-related changes in the human brain.

Pathomechanisms of atrophy in insular cortex in Alzheimer's disease

The insular cortex is associated with neuropsychiatric symptoms, changes in cardiovascular and autonomic control, and mortality in Alzheimer's dementia. However, the insular cortex does not provide information on the contribution of the other cortices to cognitive decline. We hypothesized that the factors that affect to atrophy in insular cortex are different from other cortical regions. A total of 42 patients with probable Alzheimer's dementia were included in the analyses. The manual drawing of regions of interest was used to detect insular cortex located in the deep gray matter and to avoid coatrophy. Covariates, which could affect to the atrophy of the cerebral cortex, were selected based on previous studies. Any of the demographic factors, vascular risk factors, and the severity scales of dementia was not associated with any insular volume ratio. We suggest that the pathomechanisms of atrophy in insular cortex are different from those of other cortex regions in Alzheimer's disease.

HPIminer: A text mining system for building and visualizing human protein interaction networks and pathways

The knowledge on protein-protein interactions (PPI) and their related pathways are equally important to understand the biological functions of the living cell. Such information on human proteins is highly desirable to understand the mechanism of several diseases such as cancer, diabetes, and Alzheimer's disease. Because much of that information is buried in biomedical literature, an automated text mining system for visualizing human PPI and pathways is highly desirable. In this paper, we present HPIminer, a text mining system for visualizing human protein interactions and pathways from biomedical literature. HPIminer extracts human PPI information and PPI pairs from biomedical literature, and visualize their associated interactions, networks and pathways using two curated databases HPRD and KEGG. To our knowledge, HPIminer is the first system to build interaction networks from literature as well as curated databases. Further, the new interactions mined only from literature and not reported earlier in databases are highlighted as new. A comparative study with other similar tools shows that the resultant network is more informative and provides additional information on interacting proteins and their associated networks.

Meta-analysis of the association between polymorphisms of estrogen receptor α genes rs9340799 and rs2234693 and Alzheimer's disease: evidence from 23 articles

OBJECTIVE

A meta-analysis was performed to better clarify the association between polymorphisms of estrogen receptor α genes rs9340799 and rs2234693 and risk of Alzheimer's disease (AD).

METHODS

Pooled odds ratios (ORs) with 95% confidence intervals (CIs) from fixed and random effect models were calculated. Heterogeneity among studies was evaluated using the I(2). Meta-regression was used to explore the potential sources of between-study heterogeneity.

RESULTS

A total of 23 studies about rs9340799 and 24 studies about rs2234693 were included in this meta-analysis. The combined evidence suggested that the x allele of rs9340799 had a significant protective effect on the risk of AD in codominant model (ORs = 0.893, 95%CIs = 0.822-0.970), especially for AD in Asia and sporadic AD (SAD). The p allele of rs2234693 was associated with decreased risk of AD in codominant model for patients with SAD. No publication bias was detected.

CONCLUSIONS

This meta-analysis suggested that x allele of rs9340799 might have a protective effect on the risk of AD in Asia and in patients with SAD. In addition, the p allele of rs2234693 might decrease the risk of patients with SAD.

Estrogen receptor α gene polymorphisms and risk of Alzheimer's disease: evidence from a meta-analysis

Objective

Human estrogen receptor α (ESR1), a member of the nuclear receptor superfamily of ligand-activated transcription factors, is one of the key mediators of hormonal response in estrogen-sensitive tissues. Accumulating evidence has demonstrated that two of the most widely studied single-nucleotide polymorphisms in ESR1 – PvuII (T/C, rs223493) and Xbal (A/G, rs9340799) – are possibly associated with Alzheimer’s disease (AD). However, individual study results are still controversial.

Materials and methods

We searched PubMed, Embase, Web of Science, Science Direct, SpringerLink, and the Chinese National Knowledge Infrastructure databases for eligible studies assessing the association of ESR1 polymorphisms and AD risk (last search performed in November 2013). Thereafter, a meta-analysis of 13,192 subjects from 18 individual studies was conducted to evaluate the association between ESR1 polymorphisms and susceptibility to AD.

Results

The results indicated that a significant association was found between the ESR1 PvuII polymorphism and AD risk in Caucasian populations (CC + CT versus TT, odds ratio [OR] 1.14, 95% confidence interval [CI] 1.02–1.28, P=0.03; CT versus TT, OR 1.16, 95% CI 1.02–1.31, P=0.02), whereas no evidence of association was found in Asian populations. Nevertheless, we did not find any significant association between the ESR1 XbaI polymorphism and AD risk for any model in Caucasian and Asian populations (all P>0.05).

Conclusion

Based on this meta-analysis, we conclude that the ESR1 PvuII polymorphism might be a risk factor in AD development in Caucasian populations, not in Asian populations. Further confirmation is needed from better-designed and larger studies.

Common variants in psychiatric risk genes predict brain structure at birth

Studies in adolescents and adults have demonstrated that polymorphisms in putative psychiatric risk genes are associated with differences in brain structure, but cannot address when in development these relationships arise. To determine if common genetic variants in disrupted-in-schizophrenia-1 (DISC1; rs821616 and rs6675281), catechol-O-methyltransferase (COMT; rs4680), neuregulin 1 (NRG1; rs35753505 and rs6994992), apolipoprotein E (APOE; ε3ε4 vs. ε3ε3), estrogen receptor alpha (ESR1; rs9340799 and rs2234693), brain-derived neurotrophic factor (BDNF; rs6265), and glutamate decarboxylase 1 (GAD1; rs2270335) are associated with individual differences in brain tissue volumes in neonates, we applied both automated region-of-interest volumetry and tensor-based morphometry to a sample of 272 neonates who had received high-resolution magnetic resonance imaging scans. ESR1 (rs9340799) predicted intracranial volume. Local variation in gray matter (GM) volume was significantly associated with polymorphisms in DISC1 (rs821616), COMT, NRG1, APOE, ESR1 (rs9340799), and BDNF. No associations were identified for DISC1 (rs6675281), ESR1 (rs2234693), or GAD1. Of note, neonates homozygous for the DISC1 (rs821616) serine allele exhibited numerous large clusters of reduced GM in the frontal lobes, and neonates homozygous for the COMT valine allele exhibited reduced GM in the temporal cortex and hippocampus, mirroring findings in adults. The results highlight the importance of prenatal brain development in mediating psychiatric risk.

Prospective analysis of the association between estrogen receptor gene variants and the risk of cognitive decline in elderly women

A plethora of data suggests a role for estrogen in cognitive function and genetic variants in the estrogen receptors ESR1 and ESR2 have been implicated in a range of hormone-sensitive diseases. It remains unknown however, whether ESR polymorphisms are associated with the risk of decline in specific domains of cognitive function. Data came from 3799 non-demented, community-dwelling elderly women recruited in France to the 3C Study. A short cognitive test battery was administered at baseline and 2, 4 and 7 years follow-up to assess global function, verbal fluency, visual memory, psychomotor speed and executive function. Detailed socio-demographic, behavioral, physical and mental health information was also gathered and genotyping of five common ESR1 and ESR2 polymorphisms was also performed. In multivariable-adjusted Cox analysis, ESR1 rs2234693 and rs9340799 were not significantly associated with the risk of decline on any of the cognitive tasks. However, significant associations with ESR2 polymorphisms were identified. The A allele of rs1256049 was associated with an increased risk of substantial decline in visual memory (HR:1.64, 95% CI: 1.23-2.18, p=0.0007), psychomotor speed (HR:1.43, 95% CI: 1.12-1.83, p=0.004), and on the incidence of Mild Cognitive Impairment (HR:1.31, 95% CI: 1.05-1.64, p=0.02). There was also a weaker association between the A allele of rs4986938 and a decreased risk of decline in psychomotor speed. Our large multicentre prospective study provides preliminary evidence that ESR2 genetic variants may be associated with specific cognitive domains and suggests that further examination of the role of this gene in cognitive function is warranted.

Oestrogen receptor polymorphisms are an associated risk factor for mild cognitive impairment and Alzheimer disease in women APOE {varepsilon}4 carriers: a case-control study

OBJECTIVES

Examine the role of single nucleotide polymorphisms (SNPs) in the oestrogen receptor (ER) genes: rs9340799, rs2234693, rs2228480 (in the ESR1 gene) and rs4986938 (in the ESR2 gene) as a risk factor for amnesic mild cognitive impairment (MCIa) and Alzheimer's disease (AD) and its possible association with the apolipoprotein E (APOE) gene.

DESIGN

We have investigated the independent and combined association of different alleles of the oestrogen receptor genes and APOE*ε4 allele with cognitive impairment using a case-control design.

SETTING

Participants were prospectively recruited from the neurology departments of several Basque Country hospitals.

PARTICIPANTS

This study comprised 816 Caucasian participants who were aged 50 years and older: 204 MCIa, 350 sporadic patients with AD and 262 healthy controls.

PRIMARY AND SECONDARY OUTCOME MEASURES

Clinical criteria and neuropsychological tests were used to establish the diagnostic groups (MCIa, AD and healthy controls). A dichotomous variable was used for each allele and genotype and the association with MCIa and AD was established using Logistic Regression Models.

RESULTS

Neither alleles nor genotypes of SNPs rs9340799, rs2234693, rs2228480 and rs4986938 of oestrogen receptor genes (ESR1 and ESR2) are independently associated with the risk of MCIa or AD. However, the genetic profile created with the combination of the less represented alleles of these SNPs (expressed as XPAA) was associated with an increased risk for MCIa (OR=3.30, 95% CI 1.28 to 8.54, p=0.014) and AD (OR=5.16, 95% CI 2.19 to 12.14, p<0.001) in women APOE*ε4 allele carriers.

CONCLUSIONS

The less represented alleles of SNPs studied are associated with MCIa and AD in APOE*E4 carriers. In particular, the genetic profile created with the less represented alleles of ESR1 and ESR2 SNPs are associated with an increased risk for MCIa and AD in women APOEε4 allele carriers.

Understanding Youth Antisocial Behavior Using Neuroscience through a Developmental Psychopathology Lens: Review, Integration, and Directions for Research

Youth antisocial behavior (AB) is an important public health concern impacting perpetrators, victims, and society. Functional neuroimaging is becoming a more common and useful modality for understanding neural correlates of youth AB. Although there has been a recent increase in neuroimaging studies of youth AB and corresponding theoretical articles on the neurobiology of AB, there has been little work critically examining the strengths and weaknesses of individual studies and using this knowledge to inform the design of future studies. Additionally, research on neuroimaging and youth AB has not been integrated within the broader framework of developmental psychopathology. Thus, this paper provides an in-depth review of the youth AB functional neuroimaging literature with the following goals: 1. to evaluate how this literature has informed our understanding of youth AB, 2. to evaluate current neuroimaging studies of youth AB from a developmental psychopathology perspective with a focus on integrating research from neuroscience and developmental psychopathology, as well as placing this research in the context of other related areas (e.g., psychopathy, molecular genetics), and 3. to examine strengths and weaknesses of neuroimaging and behavioral studies of youth AB to suggest how future studies can develop a more informed and integrated understanding of youth AB.

Oestrogen alpha-receptor variant and two-year memory decline in midlife Australian women

OBJECTIVE

To prospectively examine the influence of the oestrogen-α receptor (ESR1)PvuII polymorphism on changes in memory performance over a 2-year period among 80 midlife postmenopausal Australian women.

METHODS

Healthy women aged 56-67 years were administered a battery of four memory (verbal and non-verbal) tasks at baseline and 2 years later.

RESULTS

Carriers of the ESR1 p allele had significantly greater declines in logical memory compared to participants with the PP genotype, independent of demographic characteristics (e.g. age), chronic illness (e.g. hypertension), sleep aid usage, hormone levels, apolipoprotein E e4 status and prospective changes in mood, smoking and alcohol consumption.

CONCLUSION

These findings provide preliminary evidence for larger and longer prospective trials that will be able to determine if the p allele of the ESR1PvuII polymorphism is a potential biomarker of logical memory decline among aging women.

Progression from amnesic mild cognitive impairment to Alzheimer's disease: ESR1 and ESR2 polymorphisms and APOE gene

BACKGROUND

Many genes have been studied to determine how they might be involved in Alzheimer's disease (AD). Estrogens have a protective effect in the central nervous system. The mechanisms of action of estrogens are mediated by two estrogen receptors (ERs), ERα and ERβ. Thus, these genes could also play a role in the progression of amnesic mild cognitive impairment (MCIa) to AD. The aim of this study was to examine the role of ER single nucleotide polymorphisms (SNPs) as a risk factor for MCIa, as well as the interaction with apolipoprotein E (APOE) ε4 in the progression to AD.

METHODS

79 MCIa patients and 138 healthy controls were analyzed. SNPs were genotyped via restriction fragment length polymorphisms and real-time PCR, RT-PCR or RT-PCR (TaqMan) assays.

RESULTS

There is a lack of association between MCIa patients who converted to AD and ER SNPs. APOE ε4 allele is an independent risk factor of MCIa (OR=1.86; 95% CI=1.02-3.38, p=0.042) with a high prevalence in converted subjects. APOE ε4 is able to predict the progression from MCIa patients to AD (OR=2.55; 95% CI=1.20-5.42, p=0.015).

CONCLUSIONS

The presence of the APOE ε4 allele, and not the alleles of ER SNPs, is a risk factor for MCIa. Furthermore, APOE genotype seems to predict the conversion from MCIa to AD.

Estrogen receptor alpha gene variants and major depressive episodes

BACKGROUND

Despite evidence of estrogen's mood-enhancing effects, the association between estrogen receptor (ER) gene variants and lifetime major depression has been insufficiently studied.

METHODS

3987 community-dwelling women aged 65years and over were recruited in France as part of the Three City Study. Current and past major depressive disorders (MDD) were diagnosed using the Mini-International Neuropsychiatry Interview, according to DSM-IV criteria. The association between two common estrogen receptor alpha (ESR1) polymorphisms with lifetime MDD was examined using adjusted logistic regression models, taking into account the age at first depressive episode and the recurrence of depression.

RESULTS

Women homozygous for the variant G allele of ESR1 rs9340799 had a 1.6-fold increased risk of MDD across their lifetime compared with women who were homozygous for the A allele (p=0.009). There was a similar non-significant trend for the C allele of rs2234693 being associated with an increased risk (p=0.09). Polytomous regression analysis further indicated that the GG genotype of rs9340799 was specifically associated with an increased risk of recurrent depressive episodes, regardless of the age at first onset of depression relative to the menopause.

LIMITATIONS

The duration and severity of depressive episodes was not considered in the analysis.

CONCLUSIONS

This is the first study to examine the association between ESR1 gene variants and lifetime MDD. Our findings indicate a significant association between common variants and the risk of recurrent depressive episodes. This suggests that certain depressed women could be most responsive to hormone-based treatment.

The Rotterdam Study: 2012 objectives and design update

The Rotterdam Study is a prospective cohort study ongoing since 1990 in the city of Rotterdam in The Netherlands. The study targets cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric, dermatological, oncological, and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. The findings of the Rotterdam Study have been presented in over a 1,000 research articles and reports (see www.erasmus-epidemiology.nl/rotterdamstudy ). This article gives the rationale of the study and its design. It also presents a summary of the major findings and an update of the objectives and methods.

A review of estrogen receptor alpha gene (ESR1) polymorphisms, mood, and cognition

OBJECTIVE

There are significant individual differences in the extent to which mood and cognition change as a function of reproductive stage, menstrual phase, postpartum, and hormone therapy use. This review explores the extent to which variations or polymorphisms in the estrogen receptor alpha gene (ESR1) predict cognitive and mood outcomes.

METHODS

A literature search was conducted from 1995 to November 2009 through PubMed, Embase, and PsychINFO. Twenty-five manuscripts that summarize investigations of ESR1 in mental health were reviewed.

RESULTS

Among studies investigating ESR1 in relation to cognition, 11 of 14 case-control studies reported an association between ESR1 polymorphisms and risk for developing dementia. Three of four prospective cohort studies reported an association between ESR1 polymorphisms and significant cognitive decline. There are inconsistencies between case-control and cohort studies regarding whether specific ESR1 alleles increase or decrease the risk for cognitive dysfunction. The relationships between ESR1 and cognitive impairment tend to be specific to or driven by women and restricted to risk for Alzheimer disease rather than other dementia causes. Three of five studies examining ESR1 polymorphisms in relation to anxiety or depressive symptoms found significant associations. Significant associations have also been reported between ESR1 polymorphisms and childhood-onset mood disorder and premenstrual dysphoric disorder.

CONCLUSIONS

A strong relationship between ESR1 variants and cognitive outcomes is evident, and preliminary evidence suggests a role of the ESR1 gene in certain mood outcomes. Insights into the discordant results will come from future studies that include haplotype analyses, analyses within specific ethnic/racial populations, and sex-stratified analyses.

Estrogen receptor alpha gene variants are associated with Alzheimer's disease

The present research is aimed at assessing the role of 3 estrogen receptor alpha (ESR1) gene variants in late onset Alzheimer's disease (AD) susceptibility. One thousand one hundred thirteen unrelated late onset sporadic AD patients, 1109 healthy controls and 121 neurologically healthy elderly controls were used to carry out case-control genetic association studies with ESR1 rs3844508, rs2234693, and ESR1 noncoding deletion 1 (ESR1-NCD1) polymorphisms. Thirty-five healthy male samples were used for molecular analyses. The rs2234693 polymorphism is associated with AD in our population (odds ratio [OR], 1.29; p = 0.008). The rs3844508 marker confers protection against AD in males (OR, 0.57; p = 0.001) and the deletion ESR1-NCD1 is a risk factor for AD in women (OR, 1.67; p < 0.001). Molecular analyses on ESR1-NCD1 indicate that this deletion confers a higher response to estradiol activity on ESR1 receptor and it is also associated with differential expression of ESR1 isoforms. Our results support the involvement of ESR1 gene in AD and point to the existence of sexual dimorphism for ESR1 markers. In addition, carriers of ESR1-NCD1 deletion could overrespond to estradiol action.

The Rotterdam Study: 2010 objectives and design update

The Rotterdam Study is a prospective cohort study ongoing since 1990 in the city of Rotterdam in The Netherlands. The study targets cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. The findings of the Rotterdam Study have been presented in close to a 1,000 research articles and reports (see www.epib.nl/rotterdamstudy). This article gives the rationale of the study and its design. It also presents a summary of the major findings and an update of the objectives and methods.

Hormonal treatment, mild cognitive impairment and Alzheimer's disease

A plethora of in vitro and in vivo studies have supported the neuroprotective role of estrogens and their impact on the neurotransmitter systems implicated in cognition. Recent hormonal replacement therapy (HRT) trials in non-demented postmenopausal women suggest a temporary positive effect (notably on verbal memory), and four meta-analyses converge to suggest a possible protective effect in relation to Alzheimer's disease (reducing risk by 29 to 44%). However, data from the only large randomized controlled trial published to date, the Women's Health Initiative Memory Study, did not confirm these observations and have even suggested an increase in dementia risk for women using HRT compared to controls. Apart from methodological differences, one key shortcoming of this trial has probably been the focus on late-onset (postmenopausal) hormonal changes, i.e. at a time when the neurodegenerative process has already begun and without taking into account individual lifetime exposure to hormone variability. Multifactorial models based on an exhaustive view of all hormonal events throughout the reproductive life (rather than on a specific exposure to a given steroid) together with other risk factors (notably genetic risk factors related to estrogen receptor polymorphisms) should be explored to clarify the role of hormonal risk factors, or protective factors for cognitive dysfunction and dementia.

Estrogen receptor-alpha variants increase risk of Alzheimer's disease in women with Down syndrome

BACKGROUND

Genetic variants that affect estrogen activity may influence the risk of Alzheimer's disease (AD). Two tightly linked polymorphisms (PvuII and XbaI) in the first intron of estrogen receptor 1 (ESR1), the gene for ER-alpha, have been reported to influence estrogen receptor expression and may influence the risk of AD.

METHODS

We examined the relation of polymorphisms in ESR1 to the risk of AD in women with Down syndrome. The subjects (181 women with DS, 41-78 years of age) were followed at 14- to 18-month intervals. Information from cognitive assessments, caregiver interviews, medical record reviews and neurological examinations was used to classify dementia. Genomic DNA was genotyped for 5 single-nucleotide polymorphisms in the upstream region and the first exon/intron of the ESR1 gene. Their association with dementia risk was evaluated, adjusting for covariates.

RESULTS

Women with at least 1 copy of the C allele at rs2234693 (PvuII) and those homozygous for the C allele at rs2077647 had an almost 3-fold increase in the risk of AD, compared with women without the C allele. The increased risks were independent of the apolipoprotein E genotype.

CONCLUSION

These findings support a role for estrogen receptor activity in the development of AD in women with Down syndrome.

Estrogen Receptor 1 gene (ESR1) variants in Alzheimer's disease. Results of a meta-analysis

BACKGROUND AND AIMS

There is some disagreement between clinical and basic science as to the benefit of estrogen in preventing cognitive decline. For cardiovascular disease, estrogen effects have been shown to vary with estrogen receptor (ESR) genotype. The present study was conceived to review evidence of ESR association with Alzheimer's disease (AD) which could account for the variability observed in estrogen treatment outcome.

METHODS

A meta-analysis was performed on data from 8288 cases and controls, controlling for ethnicity (Asian vs European). To explore the specificity of our findings further, a second meta-analysis of association studies was then appended, addressing non-AD forms of dementia or cognitive impairment (total n=11036).

RESULTS

A significant overall association of AD with two neighboring ESR1 variants located in a transcription-enhancing region (p=0.015) was noted. The genotypic effect was driven by the minor alleles in Asian populations, and did not reach significance in European samples (OR=1.1, p>0.267). When the phenotype was extended to other forms of dementia or cognitive impairment, the association was no longer observed.

CONCLUSIONS

ESR1 variability was confirmed to modulate susceptibility to AD in Asian individuals, but not in Europeans. More research is required to address possible clinical implications, e.g., for hormone replacement therapy in early stages of AD.

Estrogen receptor alpha-351 XbaI*G and -397 PvuII*C-related genotypes and alleles are associated with higher susceptibilities of endometriosis and leiomyoma

Endometriosis and leiomyoma are both common estrogen-related gynaecological diseases. We aimed to elucidate the association of estrogen receptor alpha (ERalpha)-351 A>G (XbaI) and -397 T>C (PvuII) gene polymorphisms with endometriosis and leiomyoma. Women were divided into three groups: (i) severe endometriosis (n = 112), (ii) leiomyoma (n = 106) and (iii) normal controls (n = 110). Genomic DNA was obtained from peripheral leukocytes. ERalpha-351 A/G XbaI and -397 T/C PvuII polymorphisms were assayed by the method of PCR and restriction fragment length polymorphism (RFLP). Genotypes and allelic frequencies in each group were compared. The genotype/allele frequencies of ERalpha-351 and -397 polymorphisms in endometriosis or leiomyoma groups were different from those of normal controls. ERalpha mutant-related genotypes/alleles (-351G and -397C) presented higher percentages in the endometriosis/leiomyoma population compared with normal controls. Proportions of ERalpha-351 AA/AG/GG genotypes and A/G alleles in each group were (i) 26.8/57.1/16.1 and 55.4/44.6%; (ii) 19.8/52.8/27.4 and 46.2/53.8% and (iii) 33.6/64.6/1.8 and 65.9/34.1%. Proportions of ERalpha-397 TT/TC/CC genotypes and T/C alleles in each group were (i) 24.1/60.7/15.2 and 54.5/45.5%; (ii) 23.6/70.8/5.6 and 59/41% and (iii) 54.5/40/5.5 and 74.5/25.5%. We concluded that ERalpha-351 XbaI*G- and -397 PvuII*C-related genotypes/alleles were correlated with higher susceptibilities of endometriosis or leiomyoma, which might be associated with related pathogeneses.

Effects of hormone therapy on brain morphology of healthy postmenopausal women: a Voxel-based morphometry study

OBJECTIVE

Estrogens are known to be protective in age-associated cognitive changes in humans and in neurodegeneration in animal models. The aim of this study was to evaluate the potential effects of estrogen therapy (ET) on human gray matter volume in vivo.

DESIGN

Forty healthy postmenopausal women underwent three-dimensional high-resolution magnetic resonance imaging: 17 were never treated, 16 were currently receiving ET, and 7 had had ET in the past. Voxel-based morphometry (VBM) with SPM2 was used, according to an optimized protocol, to compare women under past and current ET to those never treated. Significance threshold was set at P = 0.01, corrected by false discovery rate.

RESULTS

Voxel-based morphometry indicated that estrogen use was associated with greater gray matter volumes in the whole group of treated women, which included the cerebellum (cluster size, Z coordinates: 5,527; 5.15; -14 -54 -10), the amygdaloid-hippocampal complex (left: 19; 3.55; -22 -4 -18; right: 45; 3.61; 16 -6 -16), and extended to the frontal, temporal, parietal, and occipital neocortex. The comparison current ET versus past ET use showed that women who underwent treatment in the past had greater volumes of gray matter compared to women under current treatment.

CONCLUSIONS

ET might slow down age-related gray matter loss in postmenopausal women. The structures that exhibited greater volume in association with ET included the cerebellar and cerebral cortices and, typically involved in Alzheimer's disease, the medial temporal structures and the temporoparietal junction.

Estrogen receptor alpha and risk for cognitive impairment in postmenopausal women

The estrogen receptor alpha (ESR1) gene has been implicated in the process of cognitive impairment in elderly women. In a paired case-control study, we tested whether two ESR1 gene polymorphisms (the XbaI and PvuII sites) are risk factors for cognitive impairment as measured by the six-item Orientation-Memory-Concentration test in postmenopausal Danish women. Hormone replacement therapy, age and executive cognitive ability were examined as covariates for ESR1 gene effects on cognitive impairment. The XbaI polymorphism showed a marginal effect on cognitive abilities (P=0.054) when adjusted for executive cognitive ability. Using a dominant genetic model for the X allele, we found an elevated risk (executive cognitive ability adjusted P=0.033) for cognitive impairment. Hormone replacement therapy also had a borderline effect on cognitive ability (P=0.049) and this effect was reflected in executive cognitive ability. These data support that the ESR1 gene variants affect cognitive functioning in postmenopausal women.

Influence of serotonin receptor 2A His452Tyr polymorphism on brain temporal structures: a volumetric MR study

Serotonin (5-HT) receptors 2A are expressed in brain regions involved in memory and learning processes. Recently, a functional single nucleotide polymorphism in the 5-HT2A receptor gene leading to an amino-acid substitution at residue 452 (His452Tyr) has been involved in memory performance, persons with the rare 452Tyr allele showing poorer memory performance compared to His452His subjects. To investigate a putative structural effect of this polymorphism on temporal areas typically involved in memory processes, we performed voxel-based morphometry (VBM) and region-of-interest (ROI) volumetric analysis on high-resolution magnetic resonance images in 15 carriers and 61 noncarriers of the 452Tyr allele. ROI volumetric analysis showed a significant reduction of the fractional volume of the temporal white matter in 452Tyr carriers (0.67+/-0.07 vs 0.73+/-0.08; P=0.007). VBM confirmed this finding and in addition showed reduced grey matter in the left hippocampus, left inferior temporal gyrus, and bilaterally in the middle and superior temporal gyrus. A possible effect on synaptic plasticity or neurodevelopment might explain the influence of the His452Tyr polymorphism on temporal brain structures, and this might be the basis for poorer memory performance in 452Tyr carriers. These findings should be considered preliminary and future replication is needed.

Gene variants for osteoporosis and their pleiotropic effects in aging

The prevalence of osteoporosis is raising worldwide as improving conditions of living and treatment of other common diseases continuously increases life expectancy. Thus, osteoporosis affects most women above 80 years of age and, at the age of 50, the lifetime risk of suffering an osteoporosis-related fracture approaches 50% in women and 20% in men. Numerous genetic, hormonal, nutritional and life-style factors contribute to the acquisition and maintenance of bone mass. Among them, genetic variations explain as much as 70% of the variance for bone mineral density (BMD) in the population. Dozens of quantitative trait loci (QTLs) for BMD have been identified by genome screening and linkage approaches in humans and mice, and more than 100 candidate gene polymorphisms tested for association with BMD and/or fracture. Sequence variants in the vitamin D receptor (VDR), collagen 1 alpha 1 chain (Col1A1), estrogen receptor alpha (ESR1), interleukin-6 (IL-6) and LDL receptor-related protein 5 (LRP5) genes were all found to be significantly associated with differences in BMD and/or fracture risk in multiple replication studies. Moreover, some genes, such as VDR and IL-6, were shown to interact with non-genetic factors, i.e. calcium intake and estrogens, to modulate BMD. Since these gene variants have also been associated with other complex disorders, including cancer and coronary heart disease, they may represent common genetic susceptibility factors exerting pleiotropic effects during the aging process.