Chapter 3 Effect of Hormone Replacement Therapy on Inflammatory Biomarkers. Advances in Clinical Chemistry Volume 47. Elsevier; 2009. pp. 59-93. [DOI: 10.1016/s0065-2423(09)47003-3]

The association between menopausal status and clinical outcomes of female patients with carpal tunnel release: a retrospective observational study

BACKGROUND

The relationship between menopausal status and clinical outcomes of female patients with carpal tunnel release (CTR) has been not clearly investigated. This study aimed to evaluate the clinical outcomes of CTR among women with different menopausal statuses.

METHODS

Two hundred-eighteen consecutive female patients with carpal tunnel syndrome (CTS) who underwent surgery at our hospital between May 2016 and May 2020 were included in this study. Based on whether subjects had undergone menopause before surgery, they were divided into three groups: the premenopausal group, the early postmenopausal group (less than 10 years since menopause) and the late postmenopausal group (more than 10 years since menopause). The clinical outcome was assessed before surgery and at six-month postoperative visits using the Boston Carpal Tunnel Questionnaire (BCTQ).

RESULTS

There were 86 patients in the premenopausal group, 70 patients in the early postmenopausal group and 62 patients in the late postmenopausal group. All the groups showed significant improvements in their Symptom Severity Scale (SSS) and Functional Status Scale (FSS) compared with preoperative scores. Although, there was a significant difference between the groups based and post-surgical SSS and FSS (p < 0.05). Patients in the postmenopausal group had less improvement in SSS and FSS in comparison with those in the other groups (p < 0.05).

CONCLUSIONS

Our results showed that all the groups had significant improvement in their SSS and FSS. However, the clinical outcomes were poorer in late postmenopausal patients than in premenopausal or early postmenopausal patients. These findings can be used in pre-operative counseling and interpretation of outcomes in women with CTR.

Understanding human aging and the fundamental cell signaling link in age-related diseases: the middle-aging hypovascularity hypoxia hypothesis

Aging-related hypoxia, oxidative stress, and inflammation pathophysiology are closely associated with human age-related carcinogenesis and chronic diseases. However, the connection between hypoxia and hormonal cell signaling pathways is unclear, but such human age-related comorbid diseases do coincide with the middle-aging period of declining sex hormonal signaling. This scoping review evaluates the relevant interdisciplinary evidence to assess the systems biology of function, regulation, and homeostasis in order to discern and decipher the etiology of the connection between hypoxia and hormonal signaling in human age-related comorbid diseases. The hypothesis charts the accumulating evidence to support the development of a hypoxic milieu and oxidative stress-inflammation pathophysiology in middle-aged individuals, as well as the induction of amyloidosis, autophagy, and epithelial-to-mesenchymal transition in aging-related degeneration. Taken together, this new approach and strategy can provide the clarity of concepts and patterns to determine the causes of declining vascularity hemodynamics (blood flow) and physiological oxygenation perfusion (oxygen bioavailability) in relation to oxygen homeostasis and vascularity that cause hypoxia (hypovascularity hypoxia). The middle-aging hypovascularity hypoxia hypothesis could provide the mechanistic interface connecting the endocrine, nitric oxide, and oxygen homeostasis signaling that is closely linked to the progressive conditions of degenerative hypertrophy, atrophy, fibrosis, and neoplasm. An in-depth understanding of these intrinsic biological processes of the developing middle-aged hypoxia could provide potential new strategies for time-dependent therapies in maintaining healthspan for healthy lifestyle aging, medical cost savings, and health system sustainability.

Hormone replacement therapy in women and risk of carpal tunnel syndrome: a systematic review and metaanalysis

BACKGROUND

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy. Menopausal status and/or estrogen level may play a role in CTS. The evidence regarding the association between hormone replacement therapy (HRT) in postmenopausal women and CTS is still conflicting. This meta-analysis aimed to investigate the association between carpal tunnel syndrome (CTS) and women using hormone replacement therapy (HRT).

METHODS

A search was conducted in the PubMed/Medline, Scopus, Embase, and Cochrane databases, from their inception through July 2022. Studies which reported on the association between any type of HRT use and the risk of developing CTS in postmenopausal women compared to a control group were included. Studies which did not include a control group were excluded. Of the 1573 articles extracted from database searches, seven studies involving 270,764 women were included of which 10,746 had CTS. The association between CTS and HRT use was evaluated using the pooled odds ratio (OR) with a 95% confidence interval (CI) under random-effects modelling. Risk of bias in each study was assessed using the Newcastle-Ottawa Scale (NOS) and version 2 of the Cochrane tool for assessing risk of bias in randomized trials (RoB 2).

RESULTS

HRT use showed no statistically significant association with a higher risk of CTS with pooled odds ratio (OR) 1.49, 95% confidence interval (CI) 0.99-2.23, and p = 0.06, although high heterogeneity among the studies was observed (I² 97.0%, Q-test p-value < 0.001). Subgroup analysis of groups in non-randomized controlled studies showed a significantly increased risk of CTS, while groups in randomized controlled studies showed a decreased risk of CTS (pooled OR 1.87, 95% CI 1.24-2.83 versus pooled OR 0.79, 95% CI 0.69-0.92, respectively) with the p-value of group difference < 0.001. The risk of bias in most of the included studies was estimated to be low.

CONCLUSIONS

This meta-analysis supports the safety of using HRT in postmenopausal women with potential risk factors for CTS.

LEVEL OF EVIDENCE

I, Prognosis.

REGISTRATION

INPLASY (202280018).

Use of Hormone Replacement Therapy and Risk of Dementia: A Nationwide Cohort Study

BACKGROUND AND OBJECTIVES

Estrogen has the potential to influence brain physiology implicated in dementia pathogenesis. Hormone replacement therapy (HRT) might be expected to influence the risk of dementia. Observational data indicated that HRT was associated with reductions in dementia risk, but experimental evidence demonstrates that HRT increases the incidence of dementia. To determine the effect of HRT on the risk of dementia, a retrospective cohort study was performed using a nationwide claims dataset in Taiwan.

METHODS

A population-based longitudinal study was performed using data from the Longitudinal Health Insurance Database in Taiwan. A total of 35,024 women with HRT were enrolled as the exposed cohort and 70,048 women without HRT were selected on the basis of propensity matching as the comparison cohort. All participants were followed up until the diagnosis of dementia, death, or at the end of December 31, 2013, whichever occurred first. Overall, the average duration of follow-up (±SD) in the HRT and comparison cohorts was 12.3 (±2.3) and 12.2 (±2.4), respectively. The Cox proportional hazards regression models were conducted to produce hazard ratios (HRs) with 95% CIs to evaluate the association of HRT with the risk of dementia.

RESULTS

In the follow-up period, the cumulative incidence of dementia for the HRT cohort (20.04 per 1,000) was significantly higher than the corresponding cumulative incidence for the comparison cohort (15.79 per 1,000), resulting in an adjusted HR of 1.35 (95% CI 1.13-2.62). There was an increased risk of dementia with a higher cumulative dose of HRT prescription (p for trend <0.0001).

DISCUSSION

This cohort study documented that HRT was associated with an increased risk of dementia. The clinical implications of this study merit further investigations.

The Impact of Estrogens and Their Receptors on Immunity and Inflammation during Infection

Simple Summary

Human health is significantly affected by microbial infections. One of the largest determinants of the outcomes of such infections is the host immune response. Too weak of a response can lead to enhanced spread by the pathogen, while an overstimulated response can lead to immune-induced tissue damage. Thus, to effectively treat infected individuals, it is critical to understand the regulators that control inflammatory responses. Recently, it has become widely accepted that estrogens, a class of sex hormones, are capable of dramatically altering the responses of host cells to microbes. In this review, we discuss how estrogens change the host immune response, as well as how these changes can alter the outcome of the infection for the individual.

Abstract

Sex hormones, such as estrogen and testosterone, are steroid compounds with well-characterized effects on the coordination and development of vertebrate reproductive systems. Since their discovery, however, it has become clear that these “sex hormones” also regulate/influence a broad range of biological functions. In this review, we will summarize some current findings on how estrogens interact with and regulate inflammation and immunity. Specifically, we will focus on describing the mechanisms by which estrogens alter immune pathway activation, the impact of these changes during infection and the development of long-term immunity, and how different types of estrogens and their respective concentrations mediate these outcomes.

High Prediagnosis Inflammation-Related Risk Score Associated with Decreased Ovarian Cancer Survival

BACKGROUND

There is suggestive evidence that inflammation is related to ovarian cancer survival. However, more research is needed to identify inflammation-related factors that are associated with ovarian cancer survival and to determine their combined effects.

METHODS

This analysis used pooled data on 8,147 women with invasive epithelial ovarian cancer from the Ovarian Cancer Association Consortium. The prediagnosis inflammation-related exposures of interest included alcohol use; aspirin use; other nonsteroidal anti-inflammatory drug use; body mass index; environmental tobacco smoke exposure; history of pelvic inflammatory disease, polycystic ovarian syndrome, and endometriosis; menopausal hormone therapy use; physical inactivity; smoking status; and talc use. Using Cox proportional hazards models, the relationship between each exposure and survival was assessed in 50% of the data. A weighted inflammation-related risk score (IRRS) was developed, and its association with survival was assessed using Cox proportional hazards models in the remaining 50% of the data.

RESULTS

There was a statistically significant trend of increasing risk of death per quartile of the IRRS [HR = 1.09; 95% confidence interval (CI), 1.03-1.14]. Women in the upper quartile of the IRRS had a 31% higher death rate compared with the lowest quartile (95% CI, 1.11-1.54).

CONCLUSIONS

A higher prediagnosis IRRS was associated with an increased mortality risk after an ovarian cancer diagnosis. Further investigation is warranted to evaluate whether postdiagnosis exposures are also associated with survival.

IMPACT

Given that pre- and postdiagnosis exposures are often correlated and many are modifiable, our study results can ultimately motivate the development of behavioral recommendations to enhance survival among patients with ovarian cancer.

Incidence, laboratory diagnosis and predictors of tracheobronchial tuberculosis in patients with pulmonary tuberculosis in Chongqing, China

Tracheobronchial tuberculosis (TBTB) is reported in 10-40% of patients with pulmonary tuberculosis (PTB). Due to its non-specific presentation, the diagnosis and management are frequently delayed. The aim of the present study was to investigate the incidence, predictors and laboratory diagnosis of concomitant TBTB and PTB in Chongqing, China. Bronchoscopy was performed in all patients with newly diagnosed or relapsed PTB in order to detect TBTB between January 2018 and April 2019 in a sub-tertiary hospital in Chongqing, China. The clinical characteristics and laboratory data were analyzed to identify predictors and determine the diagnostic yield of TBTB. A total of 341 (31.4%) of the 1,085 patients with PTB who underwent the bronchoscopic examination presented with concomitant TBTB. The parameters of female sex [odds ratio (OR)=2.57], clinical symptoms (OR=6.26) and atelectasis (OR=4.3) were independent predictors of TBTB. Cough (OR=32.48) and atelectasis (OR=3.14) were independent predictors of TBTB-associated tracheobronchial stenosis. The diagnostic yields of sputum smear, bronchial brush smear, sputum culture, GeneXpert Mycobacterium tuberculosis/rifampicin resistance (GX) using sputum, GX using brushings and in bronchial brush culture used for the diagnosis of TBTB were 44.2, 44.2, 63.5, 57.7, 71.2 and 75%, respectively. GX brushings had higher diagnostic yields compared with sputum or brush smears; however, there was no significant difference between sputum/brushings cultures and GX with sputum. The incidence of TBTB in PTB was 31.4% in Chongqing, China. The parameters of female sex, atelectasis and cough were the major predictors of concomitant TBTB and associated tracheobronchial stenosis. Although GX is an accurate and rapid test to detect TBTB, additional laboratory techniques should also be adopted to improve diagnostic yields in the detection of TBTB in patients with PTB.

Menopausal hormone therapy prior to the diagnosis of ovarian cancer is associated with improved survival

PURPOSE

Prior studies of menopausal hormone therapy (MHT) and ovarian cancer survival have been limited by lack of hormone regimen detail and insufficient sample sizes. To address these limitations, a comprehensive analysis of 6419 post-menopausal women with pathologically confirmed ovarian carcinoma was conducted to examine the association between MHT use prior to diagnosis and survival.

METHODS

Data from 15 studies in the Ovarian Cancer Association Consortium were included. MHT use was examined by type (estrogen-only (ET) or estrogen+progestin (EPT)), duration, and recency of use relative to diagnosis. Cox proportional hazards models were used to estimate the association between hormone therapy use and survival. Logistic regression and mediation analysis was used to explore the relationship between MHT use and residual disease following debulking surgery.

RESULTS

Use of ET or EPT for at least five years prior to diagnosis was associated with better ovarian cancer survival (hazard ratio, 0.80; 95% CI, 0.74 to 0.87). Among women with advanced stage, high-grade serous carcinoma, those who used MHT were less likely to have any macroscopic residual disease at the time of primary debulking surgery (p for trend <0.01 for duration of MHT use). Residual disease mediated some (17%) of the relationship between MHT and survival.

CONCLUSIONS

Pre-diagnosis MHT use for 5+ years was a favorable prognostic factor for women with ovarian cancer. This large study is consistent with prior smaller studies, and further work is needed to understand the underlying mechanism.

Menopausal hormone therapy and the incidence of carpal tunnel syndrome in postmenopausal women: Findings from the Women's Health Initiative

Importance

Carpal tunnel syndrome (CTS) is a common and debilitating condition that commonly affects postmenopausal women.

Objective

To determine the effect of menopausal hormone therapy (HT) in healthy postmenopausal women on CTS risk.

Design

We conducted a secondary analysis of the Women’s Health Initiative’s (WHI) HT trials linked to Medicare claims data. Separate intention-to-treat analyses were performed for the two trials; the conjugated equine estrogens alone (CEE alone) and the trial of CEE plus medroxyprogesterone acetate (MPA) trial. (ClinicalTrials.gov, NCT number): NCT00000611.

Setting

Two randomized, double-blind, placebo-controlled trials conducted at 40 US clinical centers.

Participants

The sample size included in the analysis was 16,053 community-dwelling women aged ≥65 years at study entry or those who later aged into Medicare eligibility, and who were enrolled in Medicare (including Part A and/or Part B coverage).

Intervention

Women with hysterectomy were randomized to 0.625 mg/d of conjugated equine estrogens (CEE) or placebo (n = 8376). Women without hysterectomy were randomized to estrogen plus progestin (E+P), given as CEE plus 2.5 mg/d of medroxyprogesterone acetate (n = 14203).

Main outcome(s)

The primary outcome was incident CTS and the secondary outcome was therapeutic CTS procedure occurring during the intervention phases of the trials.

Results

A total of 16,053 women were randomized in both trials. During mean follow up of 4.5 ± 2.8 years in the CEE trial (n = 6,833), there were 203 incident CTS cases in the intervention and 262 incident CTS cases in the placebo group (HR, 0.78; 95% CI, 0.65–0.94; P = 0.009). The CEE+MPA trial (n = 9,220) followed participants for a mean of 3.7 ± 2.3 years. There were 173 incident CTS cases in the intervention compared to 203 cases in the placebo group (HR, 0.80, 95% CI, 0.65–0.97; P = 0.027).

Conclusions

These findings suggest a protective effect of menopausal HT on the incidence of CTS among postmenopausal women. A potential therapeutic role for other forms of estrogen therapy in the management of CTS warrants future research.

Association between erythrocyte levels of n-3 polyunsaturated fatty acids and depression in postmenopausal women using or not using hormone therapy

OBJECTIVE

Epidemiologic and clinical studies have suggested that hormone therapy (HT) and n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert antidepressant effects through regulation of the serotonergic pathway. The present study was conducted to evaluate the hypothesis that erythrocyte levels of n-3 PUFAs and depression were negatively associated in postmenopausal women, particularly those using HT.

METHODS

A total of 214 postmenopausal women were divided into groups defined by depression and HT status. Depression was defined as a Beck Depression Inventory score of at least 14, and the types and durations of HT were obtained from medical records.

RESULTS

Erythrocyte levels of EPA, docosapentaenoic acid (DPA), DHA, omega-3 index (sum of EPA + DHA), total n-3 PUFA, and arachidonic acid were significantly higher in women using HT than in those not using HT. There were significant negative correlations between depression and erythrocyte levels of alpha-linolenic acid (r = -0.310), DPA (r = -0.272), DHA (r = -0.209), and total n-3 PUFA (r = -0.234) in women using HT. Multivariate-adjusted logistic regression analysis also showed that depression was negatively associated with the erythrocyte levels of alpha-linolenic acid (P for trend = 0.018), DPA (P for trend = 0.014), and DHA (P for trend = 0.036), only in women using HT.

CONCLUSIONS

Negative associations between erythrocyte levels of n-3 PUFAs and depression were found in Korean postmenopausal women using HT but not in those not using HT, suggesting a synergistic effect of HT and n-3 PUFAs on depression.

Life satisfaction and inflammation in couples: an actor-partner analysis

Life satisfaction has been linked to lower cardiovascular disease mortality. However, much less is known about the biological mechanisms linking life satisfaction to physical health. In addition, the dyadic context of life satisfaction has not been considered despite increasing evidence that partners influence each other in health-relevant ways. These questions were addressed with 94 married couples who completed measures of life satisfaction and had their blood drawn for determination of interleukin-6 (IL-6) and C-reactive protein (CRP). Actor-partner models showed that higher actor levels of life satisfaction predicted lower levels of IL-6 and CRP (p's < .05), whereas partner levels of life satisfaction did not predict any measure of inflammation. The actor results were not mediated by marital satisfaction or health behaviors. Finally, no actor × partner interactions were significant and these links were not moderated by marital satisfaction. These data highlight inflammation as a potentially important biological mechanism linking actor reports of life satisfaction to lower cardiovascular mortality.

Associations between postmenopausal endogenous sex hormones and C-reactive protein: a clearer picture with regional adiposity adjustment?

OBJECTIVE

To better understand the pathogenesis of inflammatory-related diseases after menopause, we studied the adiposity-independent association between endogenous sex hormones and C-reactive protein (CRP), a biomarker of inflammation.

METHODS

We conducted a secondary, cross-sectional analysis of baseline data from the Alberta Physical Activity and Breast Cancer Prevention Trial (2003-2007), including 319 healthy, postmenopausal women not using hormone therapy. Multivariable linear regression models related serum CRP levels to estrogens, androgens, and sex hormone-binding globulin (SHBG), all on the natural logarithmic scale. Models were adjusted for age, lipids, medication, and former menopausal hormone therapy use, and also for adiposity (body mass index [BMI], per cent body fat [via whole-body dual x-ray absorptiometry], or intra-abdominal fat area [via computed tomography]).

RESULTS

Without adiposity adjustment, estrone, total estradiol, and free estradiol were significantly positively associated with CRP, whereas SHBG was significantly inversely associated with CRP. Of all adiposity measures, adjustment for BMI caused the greatest attenuation of CRP-estrogen associations; only free estradiol (β = 0.24, 95% confidence interval [CI] 0.06, 0.43) and SHBG (β = -0.37, 95% CI -0.60, -0.13) associations remained significant. Inverse associations between CRP-total testosterone became stronger with BMI adjustment (β = -0.20, 95% CI -0.40, -0.01). Differential associations across categories of BMI, former hormone therapy use, and years since menopause were suggestive, but not statistically significant (Pheterogeneity > 0.05).

CONCLUSIONS

Prospective and systems epidemiological studies are needed to understand whether or not the cross-sectional associations we observed, independent of adiposity, between CRP-SHBG, CRP-total testosterone, and CRP-free estradiol, are causal.

Associations of estradiol levels and genetic polymorphisms of inflammatory genes with the risk of ischemic stroke

Background

Estrogen plays an important role as an anti-inflammatory and neuroprotective agent in ischemic stroke. In this study, we analyzed the effect of a polygenic risk score (PRS) constructed using inflammatory genes and estradiol levels on the risk of ischemic stroke.

Methods

This case-control study was conducted with 624 ischemic stroke patients and 624 age- and gender-matched controls. The PRS estimated the polygenic contribution of inflammatory genes from ischemic stroke susceptibility loci. Estradiol levels were measured using a radioimmunoassay. High and low estradiol levels were defined according to the log-transformed median estradiol levels in female and male controls.

Results

Subjects in the fourth quartile of the PRS had a significant 1.57-fold risk of ischemic stroke (95% confidence interval [CI], 1.12 ~ 2.19), after adjusting for covariates compared to individuals in the lowest quartile. Compared to individuals with high estradiol levels and a low PRS as the reference group, those exposed to low estradiol levels and a high PRS had an increased risk of ischemic stroke (odds ratio, 3.35; 95% CI, 1.79 ~ 6.28). Similar results were also observed in males when the analysis was stratified by gender.

Conclusions

Our data suggest that the PRS can be useful in evaluating a high risk of ischemic stroke among patients, especially those exposed to low estradiol levels.

Oestrogen exerts anti-inflammation via p38 MAPK/NF-κB cascade in adipocytes

BACKGROUND

Oestrogen has anti-inflammatory property in obesity. However, the mechanism is still not defined.

OBJECTIVE

To investigate the effect of oestrogen on LPS-induced monocyte chemoattractant protein-1 (MCP-1) production in adipocytes.

METHODS

Lipopolysaccharides (LPS) was used to imitate inflammatory responses and monocyte chemotactic protein-1 (MCP-1) was selected as an inflammatory marker to observe. 17β-Estradiol (E₂), SB203580 (SB), pyrrolidine dithiocarbamate (PDTC), pertussis toxin (PTX), wortmannin (WM), p65 siRNA and p38 MAPK siRNA were pre-treated respectively or together in LPS-induced MCP-1. Then p38 MAPK and NF-κB cascade were silenced successively to observe the change of each other. Lastly, oestrogen receptor (ER) α agonist, ERβ agonist and ER antagonist were utilised.

RESULTS

LPS-induced MCP-1 largely impaired by pre-treatment with E₂, SB, PDTC or silencing NF-κB subunit. E₂ inhibited LPS-induced MCP-1 in a time- and dose-dependent manner, which was related to the suppression of p65 translocation to nucleus. Furthermore, LPS rapidly activated p38 MAPK, while E₂ markedly inhibited this activation. It markedly attenuated LPS-stimulated p65 translocation to nucleus and MCP-1 production by transfecting with p38 MAPK siRNA or using p38 MAPK inhibitor. The oestrogen's inhibitory effect was mimicked by the ERα agonist, but not by the ERβ agonist. The inhibition of E₂ on p38 MAPK phosphorylation was prevented by ER antagonist.

CONCLUSIONS

E₂ inhibits LPS-stimulated MCP-1 in adipocytes. This effect is related to the inhibition of p38 MAPK/NF-κB cascade, and ERα appears to be the dominant ER subtype in these events.

The effects of omega-3 polyunsaturated fatty acids and genetic variants on methylation levels of the interleukin-6 gene promoter

SCOPE

Omega-3 PUFAs (n-3 PUFAs) reduce IL-6 gene expression, but their effects on transcription regulatory mechanisms are unknown. We aimed to conduct an integrated analysis with both population and in vitro studies to systematically explore the relationships among n-3 PUFA, DNA methylation, single nucleotide polymorphisms (SNPs), gene expression, and protein concentration of IL6.

METHODS AND RESULTS

Using data in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study and the Encyclopedia of DNA Elements (ENCODE) consortium, we found that higher methylation of IL6 promoter cg01770232 was associated with higher IL-6 plasma concentration (p = 0.03) and greater IL6 gene expression (p = 0.0005). Higher circulating total n-3 PUFA was associated with lower cg01770232 methylation (p = 0.007) and lower IL-6 concentration (p = 0.02). Moreover, an allele of IL6 rs2961298 was associated with higher cg01770232 methylation (p = 2.55 × 10(-7) ). The association between n-3 PUFA and cg01770232 methylation was dependent on rs2961298 genotype (p = 0.02), but higher total n-3 PUFA was associated with lower cg01770232 methylation in the heterozygotes (p = 0.04) not in the homozygotes.

CONCLUSION

Higher n-3 PUFA is associated with lower methylation at IL6 promoter, which may be modified by IL6 SNPs.

Microphysiological modeling of the reproductive tract: a fertile endeavor

Preclinical toxicity testing in animal models is a cornerstone of the drug development process, yet it is often unable to predict adverse effects and tolerability issues in human subjects. Species-specific responses to investigational drugs have led researchers to utilize human tissues and cells to better estimate human toxicity. Unfortunately, human cell-derived models are imperfect because toxicity is assessed in isolation, removed from the normal physiologic microenvironment. Microphysiological modeling often referred to as 'organ-on-a-chip' or 'human-on-a-chip' places human tissue into a microfluidic system that mimics the complexity of human in vivo physiology, thereby allowing for toxicity testing on several cell types, tissues, and organs within a more biologically relevant environment. Here we describe important concepts when developing a repro-on-a-chip model. The development of female and male reproductive microfluidic systems is critical to sex-based in vitro toxicity and drug testing. This review addresses the biological and physiological aspects of the male and female reproductive systems in vivo and what should be considered when designing a microphysiological human-on-a-chip model. Additionally, interactions between the reproductive tract and other systems are explored, focusing on the impact of factors and hormones produced by the reproductive tract and disease pathophysiology.

Postmenopausal hormone therapy is not associated with risk of all-cause dementia and Alzheimer's disease

The relationship of postmenopausal hormone therapy with all-cause dementia and Alzheimer's disease dementia has been controversial. Given continued interest in the role of hormone therapy in chronic disease prevention and the emergence of more prospective studies, we conducted a systematic review to identify all epidemiologic studies meeting prespecified criteria reporting on postmenopausal hormone therapy use and risk of Alzheimer's disease or dementia. A systematic search of Medline and Embase through December 31, 2012, returned 15 articles meeting our criteria. Our meta-analysis of any versus never use did not support the hypothesis that hormone therapy reduces risk of Alzheimer's disease (summary estimate = 0.88, 95% confidence interval: 0.66, 1.16). Exclusion of trial findings did not change this estimate. There were not enough all-cause dementia results for a separate meta-analysis, but when we combined all-cause dementia results (n = 3) with Alzheimer's disease results (n = 7), the summary estimate remained null (summary estimate = 0.94, 95% confidence interval: 0.71, 1.26). The limited explorations of timing of use-both duration and early initiation-did not yield consistent findings. Our findings support current recommendations that hormone therapy should not be used for dementia prevention. We discuss trends in hormone therapy research that could explain our novel findings and highlight areas where additional data are needed.

Aging, estrogen loss and epoxyeicosatrienoic acids (EETs)

Inflammation is a key element in many cardiovascular diseases. Both estrogen loss, caused by menopause, and aging have inflammatory consequences. Epoxyeicosatrienoic acids (EETs) are anti-inflammatory molecules synthesized by various cytochrome P450 (Cyp) enzymes from arachidonic acid. EETs are in the third (Cytochrome P450) pathway of arachindonic acid metabolism, others being cyclooxygenases and lipoxygenases. We hypothesized that aging and estrogen loss would reduce levels of anti-inflammatory EETs. Adult (6 mo) and aged (22 mo) ovariectomized rats with (OP) and without (Ovx) 17-∃-estradiol replacement were used in this study. Mass spectrometry was used to measure levels of EETs and their metabolites, dihydroxyeicosatrienoic acids (DHETs). Levels of Cyp2C2, Cyp2C6, and Cyp2J2, the principal Cyps responsible for EETs synthesis, as well as soluble epoxide hydrolase (sEH), which metabolizes EETS to DHETs, were determined via western blot. Overall Cyp levels decreased with age, though Cyp2C6 increased in the liver. sEH was increased in the kidney with estrogen replacement. Despite protein changes, no differences were measured in plasma or aortic tissue levels of EETs. However, plasma 14,15 DHET was increased in aged Ovx, and 5,6 DHET in adult OP. In conclusion neither aging nor estrogen loss decreased the anti-inflammatory EETs in the cardiovascular system.

Proteomic profiling of the autoimmune response to breast cancer antigens uncovers a suppressive effect of hormone therapy

PURPOSE

Proteomics technologies are well suited for harnessing the immune response to tumor antigens for diagnostic applications as in the case of breast cancer. We previously reported a substantial impact of hormone therapy (HT) on the proteome. Here, we investigated the effect of HT on the immune response toward breast tumor antigens.

EXPERIMENTAL DESIGN

Plasmas collected 0-10 months prior to diagnosis of ER+ breast cancer from 190 postmenopausal women and 190 controls that participated in the Women's Health Initiative Observational Study were analyzed for the effect of HT on IgG reactivity against arrayed proteins from MCF-7 or SKBR3 breast cancer cell line lysates following extensive fractionation.

RESULTS

HT user cases exhibited significantly reduced autoantibody reactivity against arrayed proteins compared to cases who were Not Current users. An associated reduced level of IL-6 and other immune-related cytokines was observed among HT users relative to nonusers.

CONCLUSION AND CLINICAL RELEVANCE

Our findings suggest occurrence of a global altered immune response to breast cancer-derived proteins associated with HT. Thus a full understanding of factors that modulate the immune response is necessary to translate autoantibody panels into clinical applications.

Thrombophilic screening in Turner syndrome

AIM

The aim of this study was to determine, in patients with Turner syndrome (TS), the prevalence of thrombophilic disorders correlating with a higher risk of venous thromboembolism (VTE), to evaluate if thrombophilia is associated with the genetic features of these patients and whether screening before hormone replacement therapy (HRT) is advisable.

PATIENTS AND METHODS

We examined 82 TS patients. In all patients we analyzed activated factor VIII:C, fibrinogen, antithrombin (AT), protein C (PC), protein S (PS), activated PC resistance, and homocysteine. For every patient, an investigation for mutations in prothrombin G20210A, factor V R506Q, methylenetetrahydropholate reductase (MTHFR) C 677T and A1298C was conducted.

RESULTS

Low values of PC in 3 patients (3.70%), low values of PS in 12 (14.81%), and hyperhomocysteinemia in 4 (4.87%) were found; 52 girls (64.2%) presented hyperfibrinogenemia. Three patients were heterozygous for the prothrombin G20210A allele mutation (3.66%) and the factor V mutation was present in 4 patients (4.88%). No TS patient had a homozygous mutation. Mutations in the MTHFR gene were present in 62 girls, in 17 patients (20.7%) they were homozygous and in 45 patients (54.88%) heterozygous.

CONCLUSIONS

Considering the increased risks with the association between VTE and the higher prevalence of PC and PS deficiencies, TT genotype mutations and high level of fibrinogen, it is advisable to perform a complete thrombophilia screening in TS patients before starting HRT.

Estrogen, hormonal replacement therapy and cardiovascular disease

PURPOSE OF REVIEW

Premenopausal women have a lower risk and incidence of hypertension and cardiovascular disease (CVD) compared to age-matched men and this sex advantage for women gradually disappears after menopause, suggesting that sexual hormones play a cardioprotective role in women. However, randomized prospective primary or secondary prevention trials failed to confirm that hormone replacement therapy (HRT) affords cardioprotection. This review highlights the factors that may contribute to this divergent outcome and could reveal why young or premenopausal women are protected from CVD and yet postmenopausal women do not benefit from HRT.

RECENT FINDINGS

In addition to the two classical estrogen receptors, ERα and ERβ, a third, G-protein-coupled estrogen receptor GPR30, has been identified. New intracellular signaling pathways and actions for the cardiovascular protective properties of estrogen have been proposed. In addition, recent Women's Health Initiative (WHI) studies restricted to younger postmenopausal women showed that initiation of HRT closer to menopause reduced the risk of CVD. Moreover, dosage, duration, the type of estrogen and route of administration all merit consideration when determining the outcome of HRT.

SUMMARY

HRT has become one of the most controversial topics related to women's health. Future studies are necessary if we are to understand the divergent published findings regarding HRT and develop new therapeutic strategies to improve the quality of life for women.

Exercise training in ovariectomized rats stimulates estrogenic-like effects on expression of genes involved in lipid accumulation and subclinical inflammation in liver

We hypothesized that the reduction in liver fat accumulation known to occur with exercise training in ovariectomized (Ovx) rats is associated with reduced expression of genes involved in lipogenesis while favoring the expression of transcription factors regulating lipid oxidation. We also tested the hypothesis that liver fat accumulation in Ovx rats is associated with an increased gene expression of several inflammatory biomarkers and that exercise training would attenuate this response. Sprague-Dawley female rats (14 weeks of age) were randomly divided into 4 groups of sedentary sham-operated (Sham), Ovx, Ovx with 17β-estradiol (E2) supplementation using a pellet (0.72 mg; 0.012 mg/d) with a biodegradable carrier binder, and Ovx trained with endurance exercise. Endurance exercise training consisted of continuous running on a motor-driven rodent treadmill 5 times per week for 5 weeks. Fat accumulation in liver as well as in adipose fat depots was higher (P < .01) in Ovx than in Sham rats. This response was prevented in Ovx animals with 17β-estradiol supplementation and with endurance exercise training. Liver gene expressions of sterol regulatory element-binding protein 1-c, stearoyl coenzyme A desaturase 1 (and its protein content), carbohydrate response element binding protein, and acetyl-coenzyme A carboxylase were increased with estrogen withdrawal (P < .01). These responses were corrected with E2 supplementation alone as well as with training alone. Conversely, hepatic peroxisome proliferator-activated receptor α messenger RNA levels were lower (P < .01) after estrogen removal compared with Sham rats. The lower hepatic peroxisome proliferator-activated receptor α messenger RNA levels in Ovx rats were reincreased by E2 replacement or by exercise training. Gene expression of proinflammatory cytokines including inhibitor-κB kinase β and interleukin-6, as well as protein content of nuclear factor-κB, was higher (P < .01) in Ovx than in Sham animals. E2 supplementation or exercise training prevented the expression of the proinflammatory markers. It is concluded that exercise training reduces fat accumulation in liver of Ovx rats possibly through regulation of key molecules involved in lipogenesis and lipid oxidation. Exercise training also acts as estrogens in properly regulating the expression of inflammatory biomarkers in liver of Ovx rats.

Transdermal menopausal hormone therapy: delivery through skin changes the rules

IMPORTANCE TO THE FIELD

Transdermal hormone therapy is replacing oral estrogens and androgens as safe enhancements of life quality for postmenopausal women. Estradiol and testosterone are dosed into the microvascular circulation directly through skin so there is no first-pass hepatic transformation or deactivation of the dosed estradiol or testosterone.

AREAS COVERED IN THIS REVIEW

This review critically examines recent clinical trials describing experience with transdermal estradiol and testosterone in postmenopausal women. Transdermal estradiol is effective in the treatment of vasomotor symptoms (VMS) and can provide its benefits at higher levels of safety than have been heretofore possible with oral estrogens. Transdermal testosterone is effective in the treatment of hypoactive sexual desire disorder (HSDD) documented in multiple, well-powered randomized clinical trials with demonstrated high levels of safety.

WHAT THE READER WILL GAIN

The reader will learn that transdermal estradiol and testosterone, in properly selected postmenopausal women, significantly and safely enhance life quality, are likely to become increasingly popular, and will probably replace oral hormone therapy.

TAKE HOME MESSAGE

Transdermal delivery of native estradiol for VMS and testosterone for HSDD has significant advantages in safety and efficacy over traditional oral preparations which are now available for clinical use.

C-reactive protein and venous thromboembolism: causal or casual association?

The plasma concentration of C-reactive protein (CRP), the first acute-phase protein to be identified, increases dramatically following tissue injury or inflammation. Although the physiological role of CRP is still not fully known, it has been suggested that concentrations might increase as part of the acute-phase response for facilitating non-specific immune functions, defense against bacterial pathogens, clearance of apoptotic and necrotic cells to prevent immunization against autoantigens and acceleration of the repair process. In agreement with the evidence that inflammation plays a pivotal role in the pathogenesis of atherosclerosis, CRP concentrations have been associated with cardiovascular disease, and measurement of CRP has therefore been proposed as a valuable aid to predict and stratify the risk of myocardial infarction and stroke. Recently, some clinical and biological evidence in support of the hypothesis that CRP might be also involved in the onset of venous thrombosis have emerged. Native and monomeric CRP exert several prothrombotic activities, including activation of blood coagulation, impairment of the endogenous fibrinolytic capacity, and stimulation or enhancement of platelet adhesiveness and responsiveness. Epidemiological investigations have also shown that CRP concentrations are associated with increased risk of venous thromboembolism and, even more interestingly, that statins might be effective in reducing the risk of this pathology. Although there is increasing emphasis that CRP might not only be a marker but also an active player in the development of venous thrombosis, further evidence is needed to establish which event comes first--thrombosis or inflammation.

The estrogen receptor-alpha in osteoclasts mediates the protective effects of estrogens on cancellous but not cortical bone

Estrogens attenuate osteoclastogenesis and stimulate osteoclast apoptosis, but the molecular mechanism and contribution of these effects to the overall antiosteoporotic efficacy of estrogens remain controversial. We selectively deleted the estrogen receptor (ER)alpha from the monocyte/macrophage cell lineage in mice (ERalpha(LysM)(-/-)) and found a 2-fold increase in osteoclast progenitors in the marrow and the number of osteoclasts in cancellous bone, along with a decrease in cancellous bone mass. After loss of estrogens these mice failed to exhibit the expected increase in osteoclast progenitors, the number of osteoclasts in bone, and further loss of cancellous bone. However, they lost cortical bone indistinguishably from their littermate controls. Mature osteoclasts from ERalpha(LysM)(-/-) were resistant to the proapoptotic effect of 17beta-estradiol. Nonetheless, the effects of estrogens on osteoclasts were unhindered in mice bearing an ERalpha knock-in mutation that prevented binding to DNA. Moreover, a polymeric form of estrogen that is not capable of stimulating the nuclear-initiated actions of ERalpha was as effective as 17beta-estradiol in inducing osteoclast apoptosis in cells with the wild-type ERalpha. We conclude that estrogens attenuate osteoclast generation and life span via cell autonomous effects mediated by DNA-binding-independent actions of ERalpha. Elimination of these effects is sufficient for loss of bone in the cancellous compartment in which complete perforation of trabeculae by osteoclastic resorption precludes subsequent refilling of the cavities by the bone-forming osteoblasts. However, additional effects of estrogens on osteoblasts, osteocytes, and perhaps other cell types are required for their protective effects on the cortical compartment, which constitutes 80% of the skeleton.