The complex role of estrogens in inflammation

MRI-derived abdominal adipose tissue is associated with multisite and widespread chronic pain

INTRODUCTION

Musculoskeletal pain typically occurs in multiple sites; however, no study has examined whether excessive visceral and subcutaneous adipose tissue are associated with musculoskeletal pain. This study therefore aimed to describe the associations between MRI-derived abdominal adipose tissue and multisite and widespread chronic musculoskeletal pain.

METHODS

Data from the UK Biobank, a large prospective, population-based cohort study, were used. Abdominal MRI scans were performed at two imaging visits to quantify visceral adipose tissue and subcutaneous adipose tissue. Pain in the neck/shoulder, back, hip, knee or 'all over the body' was assessed at the corresponding visits. Mixed-effects ordinal/multinomial/logistic regression models were used for the analyses.

RESULTS

A total of 32 409 participants were included (50.8% women, mean age 55.0±7.4 years). In multivariable analyses, there was a dose-response association of visceral adipose tissue, subcutaneous adipose tissue and their ratio with the number of chronic pain sites in both women (visceral adipose tissue: OR 2.04 per SD (95% CI 1.85 to 2.26); subcutaneous adipose tissue: OR 1.60 (95% CI 1.50 to 1.70); and their ratio: OR 1.60 (95% CI 1.37 to 1.87)) and men (visceral adipose tissue: OR 1.34 (95% CI 1.26 to 1.42); subcutaneous adipose tissue: OR 1.39 (95% CI 1.29 to 1.49); and their ratio: OR 1.13 (95% CI 1.07 to 1.20)). Higher levels of adipose tissue were also associated with greater odds of reporting chronic pain in both sexes. The effect estimates of these adipose measures were relatively larger in women than in men.

CONCLUSION

Abdominal adipose tissue was associated with chronic musculoskeletal pain, suggesting that excessive and ectopic fat depositions may be involved in the pathogenesis of multisite and widespread chronic musculoskeletal pain. The identified stronger effects in women than men may reflect sex differences in fat distribution and hormones.

The Estrogen-Immune Interface in Endometriosis

Endometriosis is a gynecologic condition characterized by the growth of endometrium-like stroma and glandular elements outside of the uterine cavity. The involvement of hormonal dysregulation, specifically estrogen, is well established in the initiation, progression, and maintenance of the condition. Evidence also highlights the association between endometriosis and altered immune states. The human endometrium is a highly dynamic tissue that undergoes frequent remodeling in response to hormonal regulation during the menstrual cycle. Similarly, endometriosis shares this propensity, compounded by unclear pathogenic mechanisms, presenting unique challenges in defining its etiology and pathology. Here, we provide a lens to understand the interplay between estrogen and innate and adaptive immune systems throughout the menstrual cycle in the pathogenesis of endometriosis. Estrogen is closely linked to many altered inflammatory and immunomodulatory states, affecting both tissue-resident and circulatory immune cells. This review summarizes estrogenic interactions with specific myeloid and lymphoid cells, highlighting their implications in the progression of endometriosis.

Exploring the role of sex hormones and gender diversity in multiple sclerosis

Sex and sex hormones are thought to influence multiple sclerosis (MS) through effects on inflammation, myelination and neurodegeneration, and exogenous hormones have been explored for their therapeutic potential. However, our understanding of how sex hormones influence MS disease processes and outcomes remains incomplete. Furthermore, our current knowledge is derived primarily from studies that focus exclusively on cisgender populations with exclusion of gender-diverse people. Gender-affirming hormone therapy comprising exogenous sex hormones or sex hormone blocking agents are commonly used by transgender and gender-diverse individuals, and it could influence MS risk and outcomes at various stages of disease. A better understanding of the impact and potential therapeutic effects of both endogenous and exogenous sex hormones in MS is needed to improve care and outcomes for cisgender individuals and, moreover, for gender-diverse populations wherein an evidence base does not exist. In this Perspective, we discuss the effects of endogenous and exogenous sex hormones in MS, including their potential therapeutic benefits, and examine both established sex-based dimorphisms and the potential for gender-diverse dimorphisms. We advocate for future research that includes gender-diverse people to enhance our knowledge of the interplay of sex and sex hormones in MS, leading to the development of more effective and inclusive treatment strategies and improvement of care for all individuals with MS.

Predictive biomarkers for immune checkpoint inhibitors therapy in lung cancer

Immune checkpoint inhibitors (ICIs) have changed the treatment mode of lung cancer, extending the survival time of patients unprecedentedly. Once patients respond to ICIs, the median duration of response is usually longer than that achieved with cytotoxic or targeted drugs. Unfortunately, there is still a large proportion of lung cancer patients do not respond to ICI. Effective biomarkers are crucial for identifying lung cancer patients who can benefit from them. The first predictive biomarker is programmed death-ligand 1 (PD-L1), but its predictive value is limited to specific populations. With the development of single-cell sequencing and spatial imaging technologies, as well as the use of deep learning and artificial intelligence, the identification of predictive biomarkers has been greatly expanded. In this review, we will dissect the biomarkers used to predict ICIs efficacy in lung cancer from the tumor-immune microenvironment and host perspectives, and describe cutting-edge technologies to further identify biomarkers.

Gut Microbiota Modulation: A Novel Strategy for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint inflammation, progressive tissue damage and significant disability, severely impacting patients' quality of life. While the exact mechanisms underlying RA remain elusive, growing evidence suggests a strong link between intestinal microbiota dysbiosis and the disease's development and progression. Differences in microbial composition between healthy individuals and RA patients point to the role of gut microbiota in modulating immune responses and promoting inflammation. Therapies targeting microbiota restoration have demonstrated promise in improving treatment efficacy, enhancing patient outcomes and slowing disease progression. However, the complex interplay between gut microbiota and autoimmune pathways in RA requires further investigation to establish causative relationships and mechanisms. Here, we review the current understanding of the gut microbiota's role in RA pathogenesis and its potential as a therapeutic target.

Sexual dimorphism in aortic aneurysm: A review of the contributions of sex hormones and sex chromosomes

Aortic aneurysm is a common cardiovascular disease. Over time, the disease damages the structural and functional integrity of the aorta, causing it to abnormally expand and potentially rupture, which can be fatal. Sex differences are evident in the disease, with men experiencing an earlier onset and higher incidence. However, women may face a worse prognosis and a higher risk of rupture. While there are some studies on the cellular and molecular mechanisms of aneurysm formation, it remains unclear how sex factors contribute to sexual dimorphism. Therefore, this review aims to summarize the role of sex in the occurrence of aortic aneurysms, offering valuable insights for disease prevention and the development of appropriate treatment options.

New insights into the combined effects of aflatoxin B1 and Eimeria ovinoidalis on uterine function by disrupting the gut-blood-reproductive axis in sheep

BACKGROUND

Sheep coccidiosis is an infectious parasitic disease that primarily causes diarrhea and growth retardation in young animals, significantly hindering the development of the sheep breeding industry. Cereal grains and animal feeds are frequently contaminated with mycotoxins worldwide, with aflatoxin B1 (AFB1) being the most common form. AFB1 poses a serious threat to gastrointestinal health upon ingestion and affects the function of parenteral organs, thus endangering livestock health. However, the impact of the combined effects of coccidia and AFB1 on the reproductive system of sheep has not been reported. Therefore, this study utilized sheep as an animal model to investigate the mechanisms underlying the reproductive toxicity induced by the individual or combined effects of AFB1 and Eimeria ovinoidalis (E. ovinoidalis) on the gut-blood-reproductive axis.

RESULTS

The results showed that AFB1 and coccidia adversely affect the reproductive system defense of sheep by altering uterine histopathology and hormone levels and triggering inflammation, which is associated with changes in the gut microbiota and metabolites. Moreover, co-exposure to AFB1 and coccidia disrupted the intestinal structure of the colon, resulting in reduced crypt depth. The impaired barrier function of the colon manifests primarily through the suppression of barrier protein expression, changes in the gut microbiome composition, and disruptions in gut metabolism. Importantly, the levels of blood inflammatory factors (IL-6, IL-10, TNF-α, and LPS) increased, suggesting that exposure to AFB1 and coccidia compromises the function of uterine organs in sheep by perturbing the gut-blood-reproductive axis. Blood metabolomics analysis further revealed that the differential metabolites predominantly concentrate in the amino acid pathway, particularly N-acetyl-L-phenylalanine. This metabolite is significantly correlated with IL-6, TNF-α, LPS, ERα, and ERβ, and it influences hormone levels while inducing uterine damage through the regulation of the downstream genes PI3K, AKT, and eNOS in the relaxin signaling pathway, as demonstrated by RNA sequencing.

CONCLUSIONS

These findings reveal for the first time that the combined effects of AFB1 and E. ovinoidalis on sheep uterine function operate at the level of the gut-blood-reproductive axis. This suggests that regulating gut microbiota and its metabolites may represent a potential therapeutic strategy for addressing mycotoxins and coccidia-co-induced female reproductive toxicity.

Systematic low-grade chronic inflammation and intrinsic mechanisms in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder affecting 6-20% of women of childbearing age worldwide. Immune cell imbalance and dysregulation of inflammatory factors can lead to systematic low-grade chronic inflammation (SLCI), which plays a pivotal role in the pathogenesis of PCOS. A significant higher infiltration of immune cells such as macrophages and lymphocytes and pro-inflammatory factors IL-6 and TNF-α has been detected in PCOS organ systems, impacting not only the female reproductive system but also other organs such as the cardiovascular, intestine, liver, thyroid, brain and other organs. Obesity, insulin resistance (IR), steroid hormones imbalance and intestinal microecological imbalance, deficiencies in vitamin D and selenium, as well as hyperhomocysteinemia (HHcy) can induce systematic imbalance between pro-inflammatory and anti-inflammatory cells and molecules. The pro-inflammatory cells and cytokines also interact with obesity, steroid hormones imbalance and IR, leading to increased metabolic imbalance and reproductive-endocrine dysfunction in PCOS patients. This review aims to summarize the dysregulation of immune response in PCOS organ system and the intrinsic mechanisms affecting SLCI in PCOS to provide new insights for the systemic inflammatory treatment of PCOS in the future.

17β-estradiol inhibits lipopolysaccharide-induced inflammation and pyroptosis of Leydig cells of the domestic yak (Bos grunniens) via the SIRT1/Nox4/ROS pathway

Estradiol (E2) secreted by Leydig cells (LCs) can accumulate in the testes due to constriction of the reproductive lumen. Estrogen is not only important for reproduction, but also protects against inflammation. In this study, the role of pyroptosis in testicular inflammation and the effects of E2 against inflammation and pyroptosis of yak interstitial cells were investigated. Inflamed testes exhibited structural damage and pyroptosis with decreased E2, testosterone, and estrogen receptor β (ERβ) levels in testicular fluid. E2 alone inhibited testosterone secretion and increased ERβ expression in mature LCs. In LCs, lipopolysaccharide (LPS) causes inflammation by activation of TNF-α and IL-6, and pyroptosis via activation of the classical and non-classical pyroptosis pathways. LPS inhibits sex hormone secretion and ERβ expression in LCs. E2 inhibited the LPS-induced decrease of ER expression in LCs and also inhibited LPS-induced interstitial cell inflammation and pyroptosis, which was partially blocked by Selisistat (EX-527, SIRT1 inhibitor) or Fulvestrant (ICI 182,780, E2 non-genomic receptor inhibitors). In conclusion, E2 relieved LPS-induced inflammation and pyroptosis of yak LCs via the SIRT1/Nox4/ROS pathway. This finding provides new insights into the role of estrogen in male reproductive health and offers a potential therapeutic strategy to improve testicular immune and reproductive function by modulating hormonal homeostasis.

Unique cardiometabolic factors in women that contribute to modified cardiovascular disease risk

Major risk factors of cardiovascular disease (CVD) include hypertension, obesity, diabetes mellitus and metabolic syndrome; all of which are considered inflammatory conditions. Women are disproportionately affected by inflammatory conditions, with sex differences emerging as early as adolescence. Hormonal fluctuations associated with reproductive events such as menarche, pregnancy and menopause, are hypothesized to promote a pro-inflammatory state in women. Moreover, women who have experienced inflammatory-type conditions such as polycystic ovarian syndrome (PCOS), gestational diabetes or pre-eclampsia, have a cardiometabolic phenotype that pre-disposes to increased risk of myocardial infarction, stroke and coronary heart disease. Women with no notable CVD risk factors are often relatively protected from CVD pre-menopause; but overtake men in risk of major cardiovascular events when the cardiovascular protective effects of oestrogen begin to wane. Sex differences and female-specific factors have long been considered challenging to study and this has led to an underrepresentation of females in clinical trials and lack of female-specific data from pre-clinical studies. However, there is now a clear prerogative to include females at all stages of research, despite inherent complexities and potential variability in data. This review explores recent advancements in our understanding of CVD in women. We summarise the underlying factors unique to women that can promote CVD risk factors, ultimately contributing to CVD burden and the emerging therapies aimed to combat this.

Plasma ferritin, C-reactive protein, and adenosine deaminase levels in tuberculous lymphadenitis and pleuritis and their role in monitoring treatment response

BACKGROUND

We aimed to assess the plasma levels of ferritin, C-reactive protein (CRP), and adenosine deaminase (ADA) at baseline and their utility as biomarkers to monitor response to treatment in extrapulmonary tuberculosis (EPTB) patients.

METHODS

Prospective measurements of ferritin, CRP, and ADA were done in unstimulated plasma samples of 92 EPTB (49 TB lymphadenitis and 43 TB pleuritis) patients registered for anti-TB treatment. Blood samples were taken at the start, 2, and 6 months of treatment, plasma levels of ferritin and CRP were measured by the enzyme-linked immunosorbent assay and ADA levels by kinetic chemistry method at each time point. Data was analyzed using SPSS version 22. Non-parametric tests were used for paired analysis and two groups' comparison. Spearman's rank test was used for correlation analysis. A Chi-square test was used for categorical variables. A p-value < 0.05 was considered statistically significant.

RESULTS

Before the start of treatment, plasma levels of ferritin were raised in 13% and 45%, CRP in 21% and 64%, and ADA in 70% and 60% of TB lymphadenitis and pleuritis cases respectively. Levels of all three biomarkers with raised values at baseline decreased significantly with treatment at both 2 and 6 months in all patients. [Ferritin (2 months p = 0.001, 6 months p < 0.001), CRP (2 months p < 0.001, 6 months p < 0.001), ADA (2 months p = 0.039, 6 months p < 0.004)]. Plasma levels of ferritin (median 300 ng/ml range = 145-758 ng/ml) and CRP (median 11.73 mg/L, range = 10.45-17.84 mg/L) were significantly higher in TB pleuritis patients, while the levels of ADA were not significantly different among the two groups. Biosignatures generated by different combinations showed that a combination of all three biomarkers could predict treatment response in 83% and 100% of all patients at 2 and 6 months of treatment respectively.

CONCLUSION

A combination of serum ferritin, CRP, and ADA shows a promising role in monitoring response to treatment in TB lymphadenitis and TB pleuritis patients. Similar studies in larger cohorts are needed to establish a definite role of these biomarkers in EPTB patients.

Inhibition of neuroinflammation and neuronal damage by the selective non-steroidal ERβ agonist AC-186

BACKGROUND

AC-186 (4-[4-4-Difluoro-1-(2-fluorophenyl) cyclohexyl] phenol) is a neuroprotective non-steroidal selective oestrogen receptor modulator. This study investigated whether inhibition of neuroinflammation contributed to neuroprotective activity of this compound.

METHODS

BV-2 microglia were treated with AC-186 (0.65-5 μM) prior to stimulation with LPS (100 ng/mL). Levels of pro-inflammatory mediators and proteins were then evaluated.

RESULTS

Treatment of LPS-activated BV-2 microglia with AC-186 resulted in significant (p < 0.05) reduction in TNFα, IL-6, NO, PGE2, iNOS and COX-2. Further investigations showed that AC-186 decreased LPS-induced elevated levels of phospho-p65, phospho-IκBα and acetyl-p65 proteins, while blocking DNA binding and luciferase activity of NF-κB. AC-186 induced significant (p < 0.05) increase in protein expression of ERβ, while enhancing ERE luciferase activity in BV-2 cells. Effects of the compound on oestrogen signalling in the microglia was confirmed in knockdown experiments which revealed a loss of anti-inflammatory activity following transfection with ERβ siRNA. In vitro neuroprotective activity of AC-186 was demonstrated by inhibition of activated microglia-mediated damage to HT-22 neurons.

CONCLUSIONS

This study established that AC-186 produces NF-κB-mediated anti-inflammatory activity, which is proposed as a contributory mechanism involved in its neuroprotective actions. It is suggested that the anti-inflammatory activity of this compound is linked to its agonist effect on ERβ.

Oestrogens, adipose tissues and environmental exposures influence obesity and diabetes across the lifecycle

Endogenous oestrogens regulate essential functions to include menstrual cycles, energy balance, adipose tissue distribution, pancreatic β-cell function, insulin sensitivity and lipid homeostasis. Oestrogens are a family of hormones which include oestradiol (E2), oestrone (E1) and oestriol (E3). Oestrogens function by binding and activating oestrogen receptors (ERs). Phytoestrogens are plant-derived compounds which exhibit oestrogenic-like activity and can bind to ERs. Phytoestrogens exert potential oestrogenic-like benefits; however, their effects are context-dependent and require cautious consideration regarding generalised health benefits. Xenoestrogens are synthetic compounds which have been determined to disrupt endocrine function through binding to ERs. Xenoestrogens enter the body through various routes and given their chemical structure they can accumulate, posing long-term health risks. Xenoestrogens interfere with endogenous oestrogens and their functions contributing to conditions like cancer, infertility, and metabolic disorders. Understanding the interplay between endogenous and exogenous oestrogens is critical in order to determine their potential health consequences and requires further investigation. This manuscript provides a summary of the role endogenous oestrogens have in regulating metabolic functions. Additionally, we discuss the impact phytoestrogens and synthetic xenoestrogens have on biological systems across various life stages. We highlight their mechanisms of action, potential benefits, risks and discuss the need for further research to bridge gaps in understanding and mitigate exposure-related health risks.

Helper T cells: A potential target for sex hormones to ameliorate rheumatoid arthritis? (Review)

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease whose etiology is not fully understood. Defective peripheral immune tolerance and subsequent mis‑differentiation and aberrant infiltration of synovium by various immune cells, especially helper T (Th) cells, play an important role in the development of RA. There are significant sex differences in RA, but the results of studies on the effects of sex hormones on RA have been difficult to standardize and hormone replacement therapy has been limited by the potential for serious side effects. Existing research has amply demonstrated that cellular immune responses are largely determined by sex and that sex hormones play a key role in Th cell responses. Based on the aforementioned background and the plasticity of Th cells, it is reasonable to hypothesize that the action of sex hormones on Th cells will hopefully become a therapeutic target for RA. The present review discussed the role of various Th cell subsets in the pathogenesis of RA and also explored the role of sex hormones on the phenotype and function of these aberrantly regulated immune cells in RA as well as other pathologic effects on RA.

Investigating the influence of oral contraceptive pill use on multiple sclerosis risk using UK Biobank data

OBJECTIVE

To investigate the association between oral contraceptive (OC) pill use and the risk of developing multiple sclerosis (MS), attempting to address the limitations present in previous studies that produced conflicting results.

DESIGN

A population-based cohort study using data from the UK Biobank.

PATIENTS

The study included 181,058 women of white ethnicity born in England between 1937 and 1970, among which 1,131 had an MS diagnosis.

INTERVENTION

Oral contraceptive use, considering the self-reported age of initiation and discontinuation. The exposures of interest include the following: ever-use, current use, duration of current use in years, and age and year at initiation.

MAIN OUTCOME MEASURES

Multiple sclerosis diagnosis (International Classification of Disease, 10th revision: G35) was used as an outcome of interest, and the associations with the exposures of interest were investigated using marginal structural models with a time-to-event approach. To adjust for confounding, we included in the models several variables, including MS polygenic risk score, education level, parity, smoking, fertility problems, obesity, and mononucleosis. We further aimed to evaluate the influence of parity using a mediation analysis.

RESULTS

The association of both ever and current OC use did not result in a statistically significant MS hazard increase (ever vs. never-users, hazard ratio [HR] = 1.30 [95% confidence interval {CI}: 0.93,1.82]; current vs. never-users, HR = 1.35 [95% CI: 0.81, 2.25]). However, we highlighted parity as an effect modifier for this association. In nulliparous women, ever and current use resulted in a significant twofold and threefold MS hazard increase (HR = 2.08 [95% CI: 1.04, 4.17] and HR = 3.15 [95% CI: 1.43, 6.9]). These associations were supported by significant MS hazard increases for a higher duration of current use and for an earlier age at initiation. We further highlighted genetic MS susceptibility as another effect modifier, as a stronger OC-MS hazard association was found in women with a low MS polygenic risk score.

CONCLUSION

Our findings highlighted how the association between OC use and MS varies on the basis of individual characteristics such as parity and genetic MS susceptibility. Importantly, current use in nulliparous women was found to be associated with a threefold increase in MS hazard. We acknowledge the need for cautious causal interpretation and further research to validate these findings across diverse populations and OC types.

Menopause and Alzheimer's disease susceptibility: Exploring the potential mechanisms

Alzheimer's Disease (AD), responsible for 62% of all dementia cases, is a progressive neurodegenerative condition that leads to cognitive dysfunction. The prevalence of AD is consistently higher in women suggesting they are disproportionately affected by this disease. Despite this, our understanding of this female AD vulnerability remains limited. Menopause has been identified as a potential contributing factor to AD in women, with earlier menopause onset associated with greater AD risk. However, the underlying mechanisms responsible for this increased risk are not fully understood. This review examines the potential role of menopause in the development of Alzheimer's Disease providing a mechanistic overview of the available literature from hormones to pathology. While literature is now emerging that indicates a role of hormonal shifts, gut dysbiosis, lipid dysregulation and inflammation, more research is needed to fully elucidate the mechanisms involved.

Exposure to Per- and Polyfluoroalkyl Substances and Risk of Psoriasis: A Population-Based Study

PFAS are a group of synthetic chemicals that have been reported to be associated with adverse health outcomes. However, the relationship of PFAS exposure with psoriasis risk has not been reported. Utilizing data from the 2003-2018 NHANES, we explored the relationship of PFAS exposure with psoriasis risk. Our study included 5370 participants and examined serum levels of five PFAS compounds: PFOA, PFOS, PFHxS, PFNA, and PFDA, along with self-reported psoriasis status. Generalized linear regression, quantile g-computation, repeated hold out WQS regression, and BKMR models were employed to assess individual and combined effects of PFAS on psoriasis risk. We found each doubling the PFOS concentration was associated with a 19% increased risk of psoriasis (OR: 1.19; 95% CI: 1.01, 1.41) in the overall population. Sex-stratified analyses indicated significant associations between PFOA and PFNA exposure and psoriasis risk in females. Mixture analyses using WQS regression indicated that PFAS mixtures were associated with an 11% increased risk of psoriasis (OR: 1.11, 95% CI: 1.01, 1.22) in females in both the negative and positive direction. BKMR analyses also indicated a positive trend of PFAS mixtures with psoriasis risk in females. Our findings indicate a possible association between PFAS exposure and psoriasis risk, particularly in females.

Unraveling the complex interplay of sex, endocrinology, and inflammation in post-Injury articular cartilage breakdown through in silico modeling

The onset of degenerative joint diseases such as post-traumatic osteoarthritis (PTOA) are associated with joint injury, biomechanical changes, and synovial biochemical anomalies. Sex and reproductive endocrinology have been emerging as potential risk factors, with epidemiological evidence revealing that female's exhibit higher PTOA risk and poorer outcomes post-injury compared to males. Sex hormones, including estradiol, progesterone, and testosterone, have been shown to regulate inflammatory signaling in immune and synovial cells, yet their collective impact on injury-induced joint inflammation and catabolism is poorly understood. Using an in silico kinetic model, we investigated the effects of sex-specific endocrine states on post-injury mechanisms in the human synovial joint. Our model results reveal that heightened estradiol levels in pre-menopausal females during the peri-ovulatory phase increase interleukin (IL)-1β expression and suppress IL-10 expression within the synovium after a simulated injury. Conversely, elevated testosterone levels in males decrease post-injury IL-1β, tumor necrosis factor alpha (TNF)-α, and stromelysin (MMP)-3 expression while increasing IL-10 production compared to females. Gaining insight into the effects of sex hormones on injury-induced inflammation and cartilage degradation provides a basis for designing future experimental and clinical studies to explore their effects on the synovial system, with a particular focus on the female sex.

Targeting the osteoclastogenic cytokine IL-9 as a novel immunotherapeutic strategy in mitigating inflammatory bone loss in post-menopausal osteoporosis

Recent discoveries have established the pivotal role of IL-9-secreting immune cells in a wide spectrum of inflammatory and autoimmune diseases. However, little is known about how IL-9 contributes to the etiology of inflammatory bone loss in PMO. We observed that IL-9 has a pathological impact on inflammatory bone loss in ovariectomized (Ovx) mice. Our in vivo temporal kinetics analysis revealed that estrogen deprivation enhanced the production of IL-9 from Th cells (majorly Th9 and Th17). Both our ex vivo and in vivo studies corroborated these findings in Ovx mice, as estrogen diminishes the potential of Th9 cells to produce IL-9. Mechanistically, Th9 cells in an IL-9-dependent manner enhance osteoclastogenesis and thus could establish themselves as a novel osteoclastogenic Th cell subset. Therapeutically neutralizing/blocking IL-9 improves bone health by inhibiting the differentiation and function of osteoclasts, Th9, and Th17 cells along with maintaining gut integrity in Ovx mice. Post-menopausal osteoporotic patients have increased IL-9-secreting Th9 cells, which may suggest a potential role for IL-9 in the development of osteoporosis. Collectively, our study identifies IL-9-secreting Th9 cells as a driver of bone loss with attendant modulation of gut-immune-bone axis, which implies IL-9-targeted immunotherapies as a potential strategy for the management and treatment of inflammatory bone loss observed in PMO.

A Prospective Study of the Relationship of COVID-19 Vaccination to Menstrual Cycle Characteristics in Adolescent Girls

PURPOSE

The current study aimed to evaluate the impact of the COVID-19 booster vaccine on menstrual cycle characteristics in adolescent girls (aged 13-20) compared to those who did not receive a booster vaccine.

METHODS

This prospective study measured menstrual cycle length for three cycles prior to and four cycles after vaccination (booster group), seven cycles without vaccination (control group). Menstrual flow, menstrual pain, and menstrual symptoms were assessed at baseline and monthly for 3 months. Stress was assessed at baseline using the PROMIS Pediatric Psychological Stress Experiences scale. Generalized linear mixed effects models were used to examine the changes in menstrual characteristics.

RESULTS

65 adolescent girls (47 booster; 18 control) were recruited via social media and from ongoing studies in the United States. Girls in the booster group experienced shorter postbooster cycles by an average 5.35 days (p = .03) compared to prebooster cycle lengths, specifically in the second postbooster cycle, while the control group did not show any changes in cycle length pre-to postbooster. Participants who received the booster in the follicular phase had shorter mean postbooster cycle length (p = .0157) compared to their prebooster cycle length. Higher stress was associated with shorter cycles (p = .03) and increased menstrual symptoms (p = <.001), regardless of group. There were no differences in menstrual flow, menstrual pain, or menstrual symptoms in either group.

DISCUSSION

The COVID-19 booster vaccine was associated with shorter cycles in adolescent girls. These data demonstrate the need for further investigation regarding potential mechanisms of these observed changes.

Sex differences in the outcome of critically Ill patients with COVID-19 - An international multicenter critical care consortium study

BACKGROUND

Sex differences in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) susceptibility, illness severity, and hospital course are widely acknowledged. The effects of sex on outcomes experienced by patients with severe Coronavirus Disease 2019 (COVID-19) admitted to the intensive care unit (ICU) remains unknown.

OBJECTIVES

To determine the effects of sex on ICU mortality in patients with COVID-19 METHODS: This retrospective analysis of an international multi-center prospective observational database included adults admitted to ICU for treatment of acute COVID-19 between 1st January 2020 and 30th June 2022. The primary outcome was ICU mortality. Multivariable Cox regression was used to ascertain the hazard of death (Hazard Ratio=HR) adjusted for pre-selected covariates. The secondary outcome was sex differences in complications of COVID-19 during hospital stay.

RESULTS

Overall, 10,259 patients (3,314 females, 6,945 males) were included with a median age of 60 (interquartile range [IQR]=49-68) and 59 (IQR=49-67) years, respectively. Baseline characteristics were similar between sexes. More females were non-smokers (65% vs. 44 %, p < 0.01) and obese (39% vs. 30 %, p < 0.01), compared to males. Also, males received greater ICU intervention (mechanical ventilation, prone ventilation, vasopressors, and tracheostomy) than females. Males had a greater hazard of death (compared to females, HR=1.14; 95 % CI=1.02-1.26). Adjustment for complications during hospital stay did not alter the hazard of death (HR=1.16; 95 % CI=1.05-1.28). Males had a significantly elevated hazard of death among patients who received ECMO (HR=1.24; 95 % CI=1.01-1.53). Male sex was associated with cardiac arrest (adjusted OR [aOR]=1.37; 95 % CI=1.16-1.62) and PE (aOR=1.28; 95 % CI=1.06-1.55).

CONCLUSION

Among patients admitted to ICU for severe COVID-19, males experienced higher severity of illness and more frequent intervention than females. Ultimately, the hazard of death was moderately elevated in males compared to females despite greater PE and cardiac arrest.

Clinical Performance and Safety of Cerviron® Vaginal Ovules in the Management of Symptomatic Cervical Lesions: A National, Multicentric Study

Background

Cervical ectropion is frequently associated with vaginal symptoms requiring therapeutic intervention. However, no scientific consensus has been reached regarding the use of local re-epithelialization therapy to prevent severe bleeding, wound inflammation, and infection of cervical lesions.

Objective

The aim of our study was to investigate the aspect of the cervix by colposcopy after a 3-month treatment with an intravaginal medical device in the context of postoperative care of the symptomatic ectropion. The study analyzed additional clinical parameters, such as the evolution of primary and secondary inflammation and the degree of cervical epithelialization as secondary objectives.

Methods

Our pilot study included 27 participants with symptomatic cervical ectopy, with or without an associated human papillomavirus infection. The treatment protocol consisted of the monthly delivery of the medical device intravaginally, during day 1 to day 15, with a total study duration of 3 months.

Results

The medical device had a positive impact on cervical epithelialization, in terms of aspect of the cervix returning to normal for 100% of the participants. Between study visits, it was observed that primary inflammation was reduced by 85.19%, whereas vaginal ulceration, colpitis, and leukorrhea were improved by 70.37%, 81.48%, and by 66.67%, respectively.

Conclusions

The degree of cervical epithelialization reflects how well the cervix has healed after an injury or infection. The device showed clinical performance in complete re-epithelialization after surgical procedures. Moreover, our study findings suggest that supportive treatment with this intravaginal medical device can be recommended for cervical wound healing in patients with human papillomavirus infection. ClinicalTrials.gov identifier: NCT04735718.

Uncovering the role of traditional Chinese medicine in immune-metabolic balance of gastritis from the perspective of Cold and Hot: Jin Hong Tablets as a case study

Chronic gastritis (CG) is a common inflammatory disease of chronic inflammatory lesion of gastric mucosa and in the diagnosis of gastritis in traditional Chinese medicine (TCM), CG can be classified into Cold ZHENG (syndrome in TCM) and Hot ZHENG. However, the molecular features of Cold/Hot ZHENG in CG and the mechanism of Cold/Hot herbs in formulae for CG remained unclear. In this study, we collected a transcriptomics data including 35 patients of Cold/Hot ZHENG CG and 3 scRNA-seq CG samples. And 25 formulae for CG and 89 herbs recorded in these formulae were also collected. We conduct a comprehensive analysis based on the combination of transcriptomics datasets and machine learning algorithms, to discover biomarkers for Cold/Hot ZHENG CG. Then the target profiles of the collected formulae and Cold/Hot herbs were predicted to uncover the features and biomarkers of them against Cold/Hot ZHENG CG. These biomarkers suggest that Hot ZHENG CG might be characterized by over-inflammation and exuberant metabolism, and Cold ZHENG CG showed a trend of suppression in immune regulation and energy metabolism. Biomarkers and specific pathways of Hot herbs tend to regulate immune responses and energy metabolism, while those of Cold herbs are more likely to participate in anti-inflammatory effects. Finally, the findings were verified based on public transcriptomics datasets, as well as transcriptomics and ELISA detection, taking Jin Hong tablets as a case study. Biomarkers like leptin and IL-6 together with proportions of immune cells showed significant changes after the intervention. These findings might reflect the mechanism and build a bridge between macro and micro views of Cold/Hot ZHENG as well as Cold/Hot herbs.

Considering the role of estradiol in the psychoneuroimmunology of perimenopausal depression

In recent years, a burgeoning field of research has focused on women's mental health and psychiatric conditions associated with perinatal and postpartum periods. An emerging trend points to the link between hormone fluctuations during pregnancy and postpartum that have immunologic consequences in cases of perinatal depression and postpartum psychosis. The transition to menopause (or "perimenopause") has garnered comparatively less attention, but existing studies point to the influential interaction of hormonal and immune pathways. Moreover, the role of this cross talk in perturbing neural networks has been implicated in risk for cognitive decline, but relatively less work has focused on the depressed brain during perimenopause. This brief review brings a psychoneuroimmunology lens to depression during the perimenopausal period by providing an overview of existing knowledge and suggestions for future research to intertwine these bodies of work.

Prenatal exposure to bisphenol AF causes toxicities in liver, spleen, and kidney tissues of SD rats

As a replacement for bisphenol A (BPA), bisphenol AF (BPAF) showed stronger maternal transfer and higher fetal accumulation than BPA. Therefore, concerns should be raised about the health risks of maternal exposure to BPAF during gestation on the offspring. In this study, SD rats were exposed to BPAF (0, 50, and 100 mg/kg/day) during gestation to investigate the bioaccumulation and adverse effects in liver, spleen, and kidney tissues of the offspring at weaning period. Bioaccumulation of BPAF in these tissues with concentrations ranging from 1.56 ng/mg (in spleen of males) to 55.44 ng/mg (in liver of females) led to adverse effects at different biological levels, including increased relative weights of spleen and kidneys, histopathological damage in liver, spleen, and kidney, organ functional damage in liver, spleen, and kidney, upregulated expression of genes related to lipid metabolism (in liver), oxidative stress response (in kidney), immunity and inflammatory (in spleen). Furthermore, dysregulated metabolomics was identified in spleen, with 217 differential metabolites screened and 9 KEGG pathways significantly enriched. This study provides a comprehensive insight into the systemic toxicities of prenatal exposure to BPAF in SD rats. Given the broad applications and widespread occurrence of BPAF, its safety should be re-considered.

COPD-Like Phenotypes in TBC-Treated Mice Can be Effectively Alleviated via Estrogen Supplement

Tris(2,3-dibromopropyl) isocyanurate (TBC), recognized as an endocrine disruptor, can cause inflammatory injury to the lung tissue of mice. To investigate the specific respiratory effects of TBC, male C57BL/6J mice were administered a daily dose of 20 mg/kg of TBC over 14 days. Postexposure, these mice developed chronic obstructive pulmonary disease (COPD)-like symptoms characterized by inflammatory lung damage and functional impairment. In light of the antiestrogenic properties of TBC, we administrated estradiol (E2) to investigate its potential protective role against TBC-induced damage and found that the coexposure of E2 notably mitigated the COPD-like phenotypes. Immunohistochemical analysis revealed that TBC exposure reduced estrogen receptor alpha (ERα) expression and increased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, while E2 treatment rebalanced the expression levels of ERα and NF-κB to their normative states. Our findings indicate that TBC, as an antiestrogenic agent, may contribute to the pathogenesis of COPD through an ERα-mediated inflammatory pathway, but that E2 treatment could reverse the impairment, providing a potentially promising remedial treatment. Given the lung status as a primary target of air pollution, the presence of antiestrogenic compounds like TBC in atmospheric particulates presents a significant concern, with the potential to exacerbate respiratory conditions such as COPD and pneumonia.

Handgrip Strength Is Inversely Associated With the Progression of Kidney Damage in a General Japanese Population: A Prospective Cohort Study

Background Handgrip strength is an indicator of muscle function and a predictor of health outcomes. However, only a few studies have examined the association between handgrip strength and the development of kidney damage. This study aimed to investigate the longitudinal association of handgrip strength with kidney damage in a general Japanese population. Methods This prospective cohort study enrolled participants with normal kidney function who attended annual health check-ups in Ibaraki Prefecture, Japan, between April 2016 and March 2020. Clinical information, including data from blood and urine tests, physiological examinations, and handgrip strength tests, was collected at enrollment. Lifestyle information was also collected via a self-administered questionnaire. The study participants were followed up for the progression of kidney damage until March 2023. Relative handgrip strength was calculated by dividing the handgrip strength by the body mass index to adjust for differences in body mass. A Cox proportional hazards model was used to examine the relationship between relative handgrip strength and the progression of kidney damage. Results A total of 4304 participants with normal kidney function were enrolled in this study. During the mean follow-up period of approximately 4 years (SD 1.8 years), 15.4% of the participants developed kidney damage. After adjusting for covariates, higher relative handgrip strength was associated with a lower risk of kidney damage in men (HR = 0.63, 95% CI: 0.43 - 0.90; p = 0.012), but no significant association was observed in women. Conclusions Higher relative handgrip strength is associated with a lower risk of kidney damage in men. This finding highlights the importance of muscle strength in preventing kidney damage.

Donor Sex and Passage Conditions Influence MSC Osteogenic Response in Mineralized Collagen Scaffolds

Contemporary tissue engineering efforts often seek to use mesenchymal stem cells (MSCs) due to their multi-potent potential and ability to generate a pro-regenerative secretome. While many have reported the influence of matrix environment on MSC osteogenic response, few have investigated the effects of donor and sex. Here, a well-defined mineralized collagen scaffold is used to study the influence of passage number and donor-reported sex on MSC proliferation and osteogenic potential. A library of bone marrow and adipose tissue-derived stem cells from eight donors to examine donor viability in osteogenic capacity in mineralized collagen scaffolds is obtained. MSCs displayed reduced proliferative capacity as a function of passage duration. Further, MSCs showed significant sex-associated variability in osteogenic capacity. Notably, MSCs from male donors displayed significantly higher cell proliferation while MSCs from female donors displayed significantly higher osteogenic response via increased alkaline phosphate activity, osteoprotegerin release, and mineral formation in vitro. The study highlights the essentiality of including donor-reported sex as an experimental variable and reporting culture expansion in future studies of biomaterial regenerative potential.

Covid-19 vaccination and menstrual bleeding disturbances among women of fertile age: a Norwegian registry study

This study evaluated the relationship between Covid-19 vaccination and menstrual bleeding disturbances using a large national registry linkage including 666,467 women between 20 and 40 years of age residing in Norway on January 1st, 2019. Information on vaccination-BNT162b2 and mRNA-1273 - was obtained from the Norwegian vaccination registry. Diagnoses of menstrual disturbances (absent/scanty, excessive, irregular/frequent menstruation, and intermenstrual bleeding) was obtained from the general practitioner database. We examined new-onset menstrual bleeding disturbances using a Cox regression comparing vaccinated to unvaccinated women, where women contributed follow-up time as unvaccinated until the day of vaccination. In addition, we conducted a self-controlled case-series analysis, and a sensitivity analysis excluding all those who remained unvaccinated throughout the pandemic, to evaluate the role of unmeasured confounding. We observed an increased risk of several menstrual bleeding disturbances after vaccination against Covid-19, ranging from an adjusted HR (aHR) of 1.18 (95% CI: 1.04, 1.33) for intermenstrual bleeding to 1.29 (95% CI: 1.23, 1.36) for irregular/frequent menstrual periods. However, estimates were fully attenuated when excluding women who remained unvaccinated at the end of follow-up (aHRs between 0.97 and 1.08). No differences were identified according to vaccine dose or type. Our self-controlled case series analysis confirmed no increased risk after a first dose of vaccination, though there was a slightly increased risk of menstrual bleeding disturbances from 61 days after vaccination with dose 2. In conclusion, the modestly increased risk of menstrual bleeding disturbances after Covid-19 vaccination appeared to reflect a role of unmeasured confounding by women who never received Covid-19 vaccinations, as associations did not remain when risk after vaccination were compared to risk before vaccination among ever vaccinated women.

Sex differences in the roles of nicotine use and puberty on youth C-reactive protein levels: Effects above and beyond adversity

Inflammation likely mediates associations between nicotine use and negative health outcomes. Sex differences have been observed in nicotine use-inflammation links, and physiological processes during puberty might allow for these differences to arise. In this cross-sectional study of 498 youth (ages 8-13, 52% girls, 77% with history of child maltreatment (CM) investigation), sex-differentiated associations between self-reported nicotine use and high-sensitivity C-reactive protein (hs-CRP) were explored. Additionally, self-reported pubertal stage was investigated as a moderator of such nicotine use-hs-CRP links. Hierarchical generalized estimating equation models were adjusted for a wide range of adversity effects: CM investigation history derived from state records, self- and caregiver-report of traumatic life events, adversity-related demographic risk factors (i.e., identification with historically marginalized racial and ethnic groups, household income), and other characteristics that may influence the variables of interest (e.g., medication use, age, body mass index). Nicotine use had a negative main effect on hs-CRP among boys (β = -0.50, p = 0.02), and pubertal stage did not moderate this association (β = 0.06, p = 0.71). In contrast, pubertal stage moderated the association between nicotine use and hs-CRP among girls (β = 0.48, p = 0.02) such that a positive association between nicotine use and hs-CRP levels was stronger at more advanced pubertal stages (β = 0.45, SE = 0.21, 95% CI [0.03, 0.87]). Findings suggest that puberty may influence the effect of nicotine on inflammation in sex-differentiated ways and have implications for timing of prevention and treatment efforts geared toward reducing nicotine use and subsequent inflammation-related health risk among youth.

Coronary microvascular disease in women: epidemiology, mechanisms, evaluation, and treatment

Coronary microvascular dysfunction (CMD) involves functional or structural abnormalities of the coronary microvasculature resulting in dysregulation of coronary blood flow (CBF) in response to myocardial oxygen demand. This perfusion mismatch causes myocardial ischemia, which manifests in patients as microvascular angina (MVA). CMD can be diagnosed non-invasively via multiple imaging techniques or invasively using coronary function testing (CFT), which assists in determining the specific mechanisms involving endothelium-independent and dependent epicardial and microcirculation domains. Unlike traditional coronary artery disease (CAD), CMD can often occur in patients without obstructive atherosclerotic epicardial disease, which can make the diagnosis of CMD difficult. Moreover, MVA due to CMD is more prevalent in women and carries increased risk of future cardiovascular events. Successful treatment of symptomatic CMD is often patient-specific risk factor and endotype targeted. This article aims to review newly identified mechanisms and novel treatment strategies for managing CMD, and outline sex-specific differences in the presentation and pathophysiology of the disease.

Sex-specific association of peripheral blood cell indices and inflammatory markers with depressive symptoms in early adolescence

BACKGROUND

Previous studies have reported the correlation of dysregulated blood cell indices and peripheral inflammatory markers with depression in adults but limited studies have examined this correlation in early adolescents.

METHODS

This study used data from the Chinese Early Adolescents Cohort Study, which was conducted in Anhui, China. Students' depression symptoms were repeatedly measured using the Chinese version of the Center for Epidemiological Studies Depression Scale for Children. Students' blood samples were collected in September 2019 and September 2021. The peripheral blood cell counts and inflammatory marker levels were determined using routine blood tests. Multivariable regression models were used to explore the associations between blood cell indices and adolescent depressive symptoms in both the whole sample and the sex-stratified samples.

RESULTS

The white blood cell (WBC) count, neutrophil count (NC), platelet (PLT) count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, and systemic immune inflammation index (SII) were positively correlated with the severity of depressive symptoms during follow-up. The mean corpuscular volume (MCV), mean hemoglobin (HGB) volume (MCH), and mean corpuscular HGB concentration (MCHC) exhibited negative temporal correlations with depressive symptoms. Additionally, several sex-specific blood cell markers were correlated with depression. Male adolescents with increased red blood cell (RBC) and female adolescents with decreased HGB levels and upregulated WBC, NC, NLR, and SII levels exhibited severe depressive symptoms at follow-up.

CONCLUSIONS

These findings suggested the potential usefulness of peripheral blood cell indices in the assessment of depression in early adolescents.

Unveiling the impact of estrogen exposure on ovarian cancer: a comprehensive risk model and immune landscape analysis

This study examines the impact of estrogenic compounds like bisphenol A (BPA), estradiol (E2), and zearalenone (ZEA) on human ovarian cancer, focusing on constructing a risk model, conducting gene set variation analysis (GSVA), and evaluating immune infiltration. Differential gene expression analysis identified 980 shared differentially expressed genes (DEGs) in human ovarian cells exposed to BPA, E2, and ZEA, indicating disruptions in ribosome biogenesis and RNA processing. Using the cancer genome atlas ovarian cancer (TCGA-OV) dataset, a least absolute shrinkage and selection operator (LASSO)-based risk model was developed incorporating prognostic genes 4-hydroxyphenylpyruvate dioxygenase like (HPDL), Thy-1 cell surface antigen (THY1), and peptidase inhibitor 3 (PI3). This model effectively stratified ovarian cancer patients into high-risk and low-risk categories, showing significant differences in overall survival, disease-specific survival, and progression-free survival. GSVA analysis linked HPDL expression to pathways related to the cell cycle, DNA damage, and repair, while THY1 and PI3 were associated with apoptosis, hypoxia, and proliferation pathways. Immune infiltration analysis revealed distinct immune cell profiles for high and low-expression groups of HPDL, THY1, and PI3, indicating their influence on the tumor microenvironment. The findings demonstrate that estrogenic compounds significantly alter gene expression and oncogenic pathways in ovarian cancer. The risk model integrating HPDL, THY1, and PI3 offers a strong prognostic tool, with GSVA and immune infiltration analyses providing insights into the interplay between these genes and the tumor microenvironment, suggesting potential targets for personalized therapies.

Menopausal state and rheumatoid arthritis: a systematic review and meta-analysis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory condition primarily affecting the joints. The higher prevalence of RA among females, combined with the known effects of sex hormones on immune function, has led researchers to investigate the potential relationship between menopausal status and the risk, severity, or progression of RA. This systematic review and meta-analysis aimed to determine the association between menopause and rheumatoid arthritis.

METHODS

In 2023, we conducted a comprehensive search across multiple databases, including Google Scholar, Scopus, PubMed/MEDLINE, Science Direct, Web of Science, EMBASE, Springer, and ProQuest. The search aimed to identify studies exploring the association between menopause and rheumatoid arthritis.

RESULTS

Our analysis revealed that post-menopausal women had a higher risk of developing rheumatoid arthritis compared to pre-menopausal women, with an estimated odds ratio of 1.35 (95% CI: 1.04-1.67). Additionally, women who experienced early menopause (defined as onset before age 45) showed significantly higher odds of developing RA, with an odds ratio of 2.97 (95% CI: 1.73-4.22).

CONCLUSION

These findings highlight the importance of considering menopausal status when assessing the risk of RA development in women. The results suggest that post-menopausal women, particularly those who experience early menopause, may be at higher risk for developing RA. Further research in this area could provide valuable insights into potential preventive measures and targeted interventions for high-risk individuals.

Acute estradiol and progesterone therapy in hospitalized adults to reduce COVID-19 severity: a randomized control trial

COVID-19 outcomes are less severe in women than men suggesting that female sex is protective. The steroids estradiol (E2) and progesterone (P4) promote anti-inflammatory immune responses and their therapeutic use for COVID-19 has been under investigation. The aim of the study was to evaluate the efficacy of a short systemic E2 and P4 combination in mitigating COVID-19 severity in hospitalized men and women. In a phase 2, single center, double blind, randomized placebo-controlled trial, ten male and female participants hospitalized for COVID-19 with scores 3-5 on the 9-point WHO ordinal scale were randomized to receive either (1) E2 cypionate (5 mg, IM) and micronized P4 (200 mg, PO), or (2) placebo-equivalent, in addition to standard of care (SOC). The primary outcome was the proportion of patients whose WHO scores improved to 1-2 on the day of discharge. Secondary outcomes included length of hospital stay (LOS), days on oxygen therapy (DOT), readmission rates (RR), adverse events (AEs), and change in circulating biomarkers using untargeted proteomics and cytokine profiling. There were no significant changes between the groups in primary outcome, LOS, DOT, RR or AEs. The E2P4 group exhibited a decrease in biomarker pathways of respiratory and gastrointestinal disease inflammation, infection by coronavirus, and immune cell trafficking and inflammatory response. A short-term E2P4 treatment in patients hospitalized for COVID-19 decreases biomarkers of inflammation. Considering the availability, low cost, and safety of E2 and P4, our results warrant additional studies to explore their effects in mitigating other viral pandemics. Clinical Trial Registration NCT04865029, ClinicalTrials.gov; (First trial registration 29/04/2021).

Further evidence that peritraumatic 17β-estradiol levels influence chronic posttraumatic pain outcomes in women, data from both humans and animals

ABSTRACT

Chronic posttraumatic pain (CPTP) is common after traumatic stress exposure (TSE) and disproportionately burdens women. We previously showed across 3 independent longitudinal cohort studies that, in women, increased peritraumatic 17β-estradiol (E2) levels were associated with substantially lower CPTP over 1 year. Here, we assessed this relationship in a fourth longitudinal cohort and also assessed the relationship between E2 and CPTP at additional time points post-TSE. Furthermore, we used a well-validated animal model of TSE to determine whether exogenous E2 administration protects against mechanical hypersensitivity. Using nested samples and data from the Advancing Understanding of RecOvery afteR traumA study (n = 543 samples, 389 participants), an emergency department-based prospective study of TSE survivors, we assessed the relationship between circulating E2 levels and CPTP in women and men using multivariate repeated-measures mixed modeling. Male and ovariectomized female Sprague Dawley rats were exposed to TSE and administered E2 either immediately after or 3 days post-TSE. Consistent with previous results, we observed an inverse relationship between peritraumatic E2 and longitudinal CPTP in women only (β = -0.137, P = 0.033). In animals, E2 protected against mechanical hypersensitivity in female ovariectomized rats only if administered immediately post-TSE. In conclusion, peritraumatic E2 levels, but not those at post-TSE time points, predict CPTP in women TSE survivors. Administration of E2 immediately post TSE protects against mechanical hypersensitivity in female rats. Together with previous findings, these data indicate that increased peritraumatic E2 levels in women have protective effects against CPTP development and suggest that immediate post-TSE E2 administration in women could be a promising therapeutic strategy for reducing risk of CPTP.

The role of ALDH2 rs671 polymorphism and C-reactive protein in the phenotypes of male ALS patients

Background

The aldehyde dehydrogenase 2 (ALDH2) rs671 (A) allele has been implicated in neurodegeneration, potentially through oxidative and inflammatory pathways. The study aims to investigate the effects of the ALDH2 rs671 (A) allele and high sensitivity C-reactive protein (hs-CRP) on the clinical phenotypes of amyotrophic lateral sclerosis (ALS) in male and female patients.

Methods

Clinical data and ALDH2 rs671 genotype of 143 ALS patients, including 85 males and 58 females, were collected from January 2018 to December 2022. All patients underwent assessment using the Chinese version of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). Complete blood count and metabolic profiles were measured. Clinical and laboratory parameters were compared between carriers and non-carriers of the rs671 (A) allele in males and females, respectively. The significant parameters and rs671 (A) Allele were included in multivariate linear regression models to identify potential contributors to motor and cognitive impairment. Mediation analysis was employed to evaluate any mediation effects.

Results

Male patients carrying rs671 (A) allele exhibited higher levels of hs-CRP than non-carriers (1.70 mg/L vs. 0.50 mg/L, p = 0.006). The rs671 (A) allele was identified as an independent risk factor for faster disease progression only in male patients (β = 0.274, 95% CI = 0.048-0.499, p = 0.018). The effect of the rs671 (A) allele on the executive function in male patients was fully mediated by hs-CRP (Indirect effect = -1.790, 95% CI = -4.555--0.225). No effects of the rs671 (A) allele or hs-CRP were observed in female ALS patients. The effects of the ALDH2 rs671 (A) allele and the mediating role of hs-CRP in male patients remained significant in the sensitivity analyses.

Conclusion

The ALDH2 rs671 (A) allele contributed to faster disease progression and hs-CRP mediated cognitive impairment in male ALS patients.

N-acetyltransferase 10 mediates cognitive dysfunction through the acetylation of GABABR1 mRNA in sepsis-associated encephalopathy

Sepsis-associated encephalopathy (SAE) is a critical neurological complication of sepsis and represents a crucial factor contributing to high mortality and adverse prognosis in septic patients. This study explored the contribution of NAT10-mediated messenger RNA (mRNA) acetylation in cognitive dysfunction associated with SAE, utilizing a cecal ligation and puncture (CLP)-induced SAE mouse model. Our findings demonstrate that CLP significantly upregulates NAT10 expression and mRNA acetylation in the excitatory neurons of the hippocampal dentate gyrus (DG). Notably, neuronal-specific Nat10 knockdown improved cognitive function in septic mice, highlighting its critical role in SAE. Proteomic analysis, RNA immunoprecipitation, and real-time qPCR identified GABABR1 as a key downstream target of NAT10. Nat10 deletion reduced GABABR1 expression, and subsequently weakened inhibitory postsynaptic currents in hippocampal DG neurons. Further analysis revealed that microglia activation and the release of inflammatory mediators lead to the increased NAT10 expression in neurons. Microglia depletion with PLX3397 effectively reduced NAT10 and GABABR1 expression in neurons, and ameliorated cognitive dysfunction induced by SAE. In summary, our findings revealed that after CLP, NAT10 in hippocampal DG neurons promotes GABABR1 expression through mRNA acetylation, leading to cognitive dysfunction.

Sex differences in osteoarthritis prevalence, pain perception, physical function and therapeutics

OBJECTIVE

Women have a higher prevalence of osteoarthritis (OA) and worse clinical courses than men. However, the underlying factors and therapeutic outcomes of these sex-specific differences are incompletely researched. This review examines the current state of knowledge regarding sex differences in OA prevalence, risk factors, pain severity, functional outcomes, and use and response to therapeutics.

METHODS

PubMed database was used with the title keyword combinations "{gender OR sex} AND osteoarthritis" plus additional manual search of the included papers for pertinent references, yielding 212 references. Additional references were added and 343 were reviewed for appropriateness.

RESULTS

Globally, women account for 60% of people with osteoarthritis, with a greater difference after age 40. The higher risk for women may be due to differences in joint anatomy, alignment, muscle strength, hormonal influences, obesity, and/or genetics. At the same radiographic severity, women have greater pain severity than men, which may be explained by biologically distinct pain pathways, differential activation of central pain pathways, differences in pain sensitivity, perception, reporting, and coping strategies. Women have greater limitations of physical function and performance than men independent of BMI, OA severity, injury history, and amount of weekly exercise. Women also have greater use of analgesic medications than men but less use of arthroplasty and poorer prognosis after surgical interventions.

CONCLUSIONS

The recognition of sex differences in OA manifestations and management could guide tailoring of sex-specific treatment protocols, and analysis of sex as a biological variable in future research would enhance development of precision medicine.

The impact of reproductive hormones on T cell immunity; normal and assisted reproductive cycles

During pregnancy, a unique immune milieu is established systemically and locally at the maternal-fetal interface. While preparing for embryonic implantation, endometrial effectors significantly change their proportions and function, which are synchronized with hormonal changes. During assisted reproductive technology cycles, various cytokines, chemokines, and immune factors dynamically change with the altered receptor expressions on the immune effectors. Thus, the hormonal regulation of immune effectors is critical to maintaining the immune milieu. In this review, hormonal effects on T cell subsets are reviewed. Sex hormones affect T cell ontogeny and development, consequently affecting their functions. Like other T cell subsets, CD4+ T helper (Th) cells are modulated by estrogen, where low estrogen concentration promotes Th1-driven cell-mediated immunity in the uterus and in vitro by enhancing IFN-γ production, while a high estrogen level decreases it. The abundance and differentiation of T regulatory (Treg) cells are controlled by estrogen, inducing Treg expansion. Conversely, progesterone maintains immune homeostasis by balancing Th1/Th2 and Th17/Treg immunity, leading to maternal-fetal tolerance. Therefore, the understanding of the hormonal impact on various T cell subsets during the reproductive cycles is critical to improving reproductive outcomes in women with recurrent pregnancy losses, repeated implantation failures, and undergoing assisted reproductive cycles.

Influence of the Onset of Menopause on the Risk of Developing Alzheimer's Disease

Menopause is a natural phase marked by the permanent cessation of menstrual cycles, occurring when the production of reproductive hormones from the ovaries stops for at least 12 consecutive months. Studies have suggested a potential connection between menopause and a heightened risk of developing Alzheimer's disease (AD), underscoring the significant role of reduced estrogen levels in the development of AD. Estrogen plays a crucial role in brain metabolism, influencing energy metabolism, synaptic plasticity, and cognitive functions. The cognitive benefits associated with hormone replacement therapy (HRT) are believed to be linked to estrogen's neuroprotective effects, either through direct action on the brain or indirectly by improving cardiovascular health. Extensive literature supports the positive impact of estrogen on brain cells. While the physiological effects of estrogen on the brain have not been consistently replicated in clinical trials, further research is crucial to provide more definitive recommendations to menopausal patients regarding the influence of HRT on AD. This review aims to comprehensively explore the interplay between menopause and AD, as well as the potential of HRT to mitigate cognitive decline in post-menopausal individuals.

Comprehensive alpha, beta, and delta cell transcriptomics reveal an association of cellular aging with MHC class I upregulation

OBJECTIVES

This study aimed to evaluate the efficacy of a purification method developed for isolating alpha, beta, and delta cells from pancreatic islets of adult mice, extending its application to islets from newborn and aged mice. Furthermore, it sought to examine transcriptome dynamics in mouse pancreatic endocrine islet cells throughout postnatal development and to validate age-related alterations within these cell populations.

METHODS

We leveraged the high surface expression of CD71 on beta cells and CD24 on delta cells to FACS-purify alpha, beta, and delta cells from newborn (1-week-old), adult (12-week-old), and old (18-month-old) mice. Bulk RNA sequencing was conducted on these purified cell populations, and subsequent bioinformatic analyses included differential gene expression, overrepresentation, and intersection analysis.

RESULTS

Alpha, beta, and delta cells from newborn and aged mice were successfully FACS-purified using the same method employed for adult mice. Our analysis of the age-related transcriptional changes in alpha, beta, and delta cell populations revealed a decrease in cell cycling and an increase in neuron-like features processes during the transition from newborn to adult mice. Progressing from adult to old mice, we identified an inflammatory gene signature related to aging (inflammaging) encompassing an increase in β-2 microglobulin and major histocompatibility complex (MHC) Class I expression.

CONCLUSIONS

Our study demonstrates the effectiveness of our cell sorting technique in purifying endocrine subsets from mouse islets at different ages. We provide a valuable resource for better understanding endocrine pancreas aging and identified an inflammaging gene signature with increased β-2 microglobulin and MHC Class I expression as a common hallmark of old alpha, beta, and delta cells, with potential implications for immune response regulation and age-related diabetes.

Association between brominated flame retardants (BFRs) and periodontitis: Results from a large population-based study

BACKGROUND

Brominated flame retardants (BFRs) are widely utilized to mitigate the flammability of various materials. Previous studies have revealed the impact of BFRs exposure on hormonal disruption and bone metabolism which are closely related to periodontitis. However, it remains unknown the potential relationship between BFRs and periodontitis. This study aimed to explore the association between BFRs exposure and periodontitis in US adults.

METHODS

The data analyzed in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) 2009-2014. Twelve serum BFRs were quantified using isotope dilution gas chromatography high-resolution mass spectrometry. Univariable and multivariable logistic regression was employed to evaluate the association between serum BFRs and periodontitis. Bayesian kernel machine regression (BKMR) analyses were utilized to assess the association between mixtures of BFRs and periodontitis.

RESULTS

A total of 3311 eligible participants were included. Serum BFRs (PBDE-47, PBDE-99, and PBDE-154) were significantly associated with periodontitis, and the odds ratios (ORs) and corresponding 95% confidence intervals(CIs) were 1.15(1.01,1.29), 1.10(1.01,1.20), and 1.12(1.01,1.25), respectively. Notably, these three BFRs were also significantly associated with the severity of periodontitis. Additionally, the BKMR model revealed a significant association between the mixture of all twelve BFRs and periodontitis.

CONCLUSIONS

This preliminary study suggests a significant association between specific serum BFRs (PBDE-47, PBDE-99, and PBDE-154) and periodontitis and its severity. Further prospective and experimental studies are warranted to validate our findings.

Investigating 7,8-Dihydroxyflavone to combat maternal immune activation effects on offspring gene expression and behaviour

Infection during pregnancy is a substantial risk factor for the unborn child to develop autism or schizophrenia later in life, and is thought to be driven by maternal immune activation (MIA). MIA can be modelled by exposing pregnant mice to Polyinosinic: polycytidylic acid (Poly-I:C), a viral mimetic that induces an immune response and recapitulates in the offspring many neurochemical features of ASD and schizophrenia, including altered BDNF-TrkB signalling and disruptions to excitatory/inhibitory balance. Therefore, we hypothesised that a BDNF mimetic, 7,8-Dihydroxyflavone (7,8-DHF), administered prophylactically to the dam may prevent the neurobehavioural sequelae of disruptions induced by MIA. Dams were treated with 7,8-DHF in the drinking water (0.08 mg/ML) from gestational day (GD) 9-20 and were exposed to Poly-I:C at GD17 (20 mg/kg, i.p.). Foetal brains were collected 6 h post Poly-I:C exposure for RT-qPCR analysis of BDNF, cytokine, GABAergic and glutamatergic gene targets. A second adult cohort were tested in a battery of behavioural tests relevant to schizophrenia and the prefrontal cortex and ventral hippocampus dissected for RT-qPCR analysis. Foetal brains exposed to Poly-I:C showed increased IL-6, but reduced expression of Ntrk2 and multiple GABAergic and glutamatergic markers. Anxiety-like behaviour was observed in adult offspring prenatally exposed to poly-I:C, which was accompanied by altered expression of Gria2 in the prefrontal cortex and Gria4 in the ventral hippocampus. While 7-8 DHF normalised the expression of some glutamatergic (Grm5) and GABAergic (Gabra1) genes in Poly-I:C exposed offspring, it also led to substantial alterations in offspring not exposed to Poly-I:C. Furthermore, mice exposed to 7,8-DHF prenatally showed increased pre-pulse inhibition and reduced working memory in adulthood. These data advance understanding of how 7,8-DHF and MIA prenatal exposure impacts genes critical to excitatory/inhibitory pathways and related behaviour.

Upregulation of Mitochondrial Sirt3 and Alleviation of the Inflammatory Phenotype in Macrophages by Estrogen

BACKGROUND

Aging and comorbidities like type 2 diabetes and obesity contribute to the development of chronic systemic inflammation, which impacts the development of heart failure and vascular disease. Increasing evidence suggests a role of pro-inflammatory M1 macrophages in chronic inflammation. A shift of metabolism from mitochondrial oxidation to glycolysis is essential for the activation of the pro-inflammatory M1 phenotype. Thus, reprogramming the macrophage metabolism may alleviate the pro-inflammatory phenotype and protect against cardiovascular diseases. In the present study, we hypothesized that the activation of estrogen receptors leads to the elevation of the mitochondrial deacetylase Sirt3, which supports mitochondrial function and mitigates the pro-inflammatory phenotype in macrophages.

MATERIALS AND METHODS

Experiments were performed using the mouse macrophage cell line RAW264.7, as well as primary male or female murine bone marrow macrophages (BMMs). Macrophages were treated for 24 h with estradiol (E2) or vehicle (dextrin). The effect of E2 on Sirt3 expression was investigated in pro-inflammatory M1, anti-inflammatory/immunoregulatory M2, and naïve M0 macrophages. Mitochondrial respiration was measured by Seahorse assay, and protein expression and acetylation were determined by western blotting.

RESULTS

E2 treatment upregulated mitochondrial Sirt3, reduced mitochondrial protein acetylation, and increased basal mitochondrial respiration in naïve RAW264.7 macrophages. Similar effects on Sirt3 expression and mitochondrial protein acetylation were observed in primary female but not in male murine BMMs. Although E2 upregulated Sirt3 in naïve M0, pro-inflammatory M1, and anti-inflammatory/immunoregulatory M2 macrophages, it reduced superoxide dismutase 2 acetylation and suppressed mitochondrial reactive oxygen species formation only in pro-inflammatory M1 macrophages. E2 alleviated the pro-inflammatory phenotype in M1 RAW264.7 cells.

CONCLUSIONS

The study suggests that E2 treatment upregulates Sirt3 expression in macrophages. In primary BMMs, female-specific Sirt3 upregulation was observed. The Sirt3 upregulation was accompanied by mitochondrial protein deacetylation and the alleviation of the oxidative and pro-inflammatory phenotype in M1 macrophages. Thus, the E2-Sirt3 axis might be used in a therapeutic strategy to fight chronic systemic inflammation and prevent the development of inflammation-linked diseases.

A History of Psycho-Neuro-Endocrine Immune Interactions in Rheumatic Diseases

BACKGROUND

All active scientists stand on the shoulders of giants and many other more anonymous scientists, and this is not different in our field of psycho-neuro-endocrine immunology in rheumatic diseases. Too often, the modern world of publishing forgets about the collective enterprise of scientists. Some journals advise the authors to present only literature from the last decade, and it has become a natural attitude of many scientists to present only the latest publications. In order to work against this general unempirical behavior, neuroimmunomodulation devotes the 30th anniversary issue to the history of medical science in psycho-neuro-endocrine immunology.

SUMMARY

Keywords were derived from the psycho-neuro-endocrine immunology research field very well known to the authors (R.H.S. has collected a list of keywords since 1994). We screened PubMed, the Cochran Library of Medicine, Embase, Scopus database, and the ORCID database to find relevant historical literature. The Snowballing procedure helped find related work. According to the historical appearance of discoveries in the field, the order of presentation follows the subsequent scheme: (1) the sensory nervous system, (2) the sympathetic nervous system, (3) the vagus nerve, (4) steroid hormones (glucocorticoids, androgens, progesterone, estrogens, and the vitamin D hormone), (5) afferent pathways involved in fatigue, anxiety, insomnia, and depression (includes pathophysiology), and (6) evolutionary medicine and energy regulation - an umbrella theory.

KEY MESSAGES

A brief history on psycho-neuro-endocrine immunology cannot address all relevant aspects of the field. The authors are aware of this shortcoming. The reader must see this review as a viewpoint through the biased eyes of the authors. Nevertheless, the text gives an overview of the history in psycho-neuro-endocrine immunology of rheumatic diseases.

Severe COVID-19 infection: An institutional review and literature overview

BACKGROUND

Our study aimed to describe the group of severe COVID-19 patients at an institutional level, and determine factors associated with different outcomes.

METHODS

A retrospective chart review of patients admitted with severe acute hypoxic respiratory failure due to COVID-19 infection. Based on outcomes, we categorized 3 groups of severe COVID-19: (1) Favorable outcome: progressive care unit admission and discharge (2) Intermediate outcome: ICU care (3) Poor outcome: in-hospital mortality.

RESULTS

Eighty-nine patients met our inclusion criteria; 42.7% were female. The average age was 59.7 (standard deviation (SD):13.7). Most of the population were Caucasian (95.5%) and non-Hispanic (91.0%). Age, sex, race, and ethnicity were similar between outcome groups. Medicare and Medicaid patients accounted for 62.9%. The average BMI was 33.5 (SD:8.2). Moderate comorbidity was observed, with an average Charlson Comorbidity index (CCI) of 3.8 (SD:2.6). There were no differences in the average CCI between groups(p = 0.291). Many patients (67.4%) had hypertension, diabetes (42.7%) and chronic lung disease (32.6%). A statistical difference was found when chronic lung disease was evaluated; p = 0.002. The prevalence of chronic lung disease was 19.6%, 27.8%, and 40% in the favorable, intermediate, and poor outcome groups, respectively. Smoking history was associated with poor outcomes (p = 0.04). Only 7.9% were fully vaccinated. Almost half (46.1%) were intubated and mechanically ventilated. Patients spent an average of 12.1 days ventilated (SD:8.5), with an average of 6.0 days from admission to ventilation (SD:5.1). The intermediate group had a shorter average interval from admission to ventilator (77.2 hours, SD:67.6), than the poor group (212.8 hours, SD:126.8); (p = 0.001). The presence of bacterial pneumonia was greatest in the intermediate group (72.2%), compared to the favorable group (17.4%), and the poor group (56%); this was significant (p<0.0001). In-hospital mortality was seen in 28.1%.

CONCLUSION

Most patients were male, obese, had moderate-level comorbidity, a history of tobacco abuse, and government-funded insurance. Nearly 50% required mechanical ventilation, and about 28% died during hospitalization. Bacterial pneumonia was most prevalent in intubated groups. Patients who were intubated with a good outcome were intubated earlier during their hospital course, with an average difference of 135.6 hours. A history of cigarette smoking and chronic lung disease were associated with poor outcomes.

17β-estradiol promotes the progression of temporomandibular joint osteoarthritis by regulating the FTO/IGF2BP1/m6A-NLRC5 axis

BACKGROUND

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative cartilage disease. 17β-estradiol (E2) aggravates the pathological process of TMJOA; however, the mechanisms of its action have not been elucidated. Thus, we investigate the influence of E2 on the cellular biological behaviors of synoviocytes and the molecular mechanisms.

METHODS

Primary fibroblast-like synoviocytes (FLSs) isolated from rats were treated with TNF-α to establish cell model, and phenotypes were evaluated using cell counting kit-8, EdU, Tanswell, enzyme-linked immunosorbent assay, and quantitative real-time PCR (qPCR). The underlying mechanism of E2, FTO-mediated NLRC5 m6A methylation, was assessed using microarray, methylated RNA immunoprecipitation, qPCR, and western blot. Moreover, TMJOA-like rat model was established by intra-articular injection of monosodium iodoacetate (MIA), and bone morphology and pathology were assessed using micro-CT and H&E staining.

RESULTS

The results illustrated that E2 facilitated the proliferation, migration, invasion, and inflammation of TNF-α-treated FLSs. FTO expression was downregulated in TMJOA and was reduced by E2 in FLSs. Knockdown of FTO promoted m6A methylation of NLRC5 and enhanced NLRC5 stability by IGF2BP1 recognition. Moreover, E2 promoted TMJ pathology and condyle remodeling, and increased bone mineral density and trabecular bone volume fraction, which was rescued by NLRC5 knockdown.

CONCLUSION

E2 promoted the progression of TMJOA.

Role of estrogen signaling in fibroblastic reticular cells for innate and adaptive immune responses in antigen-induced arthritis

Women are more prone to develop rheumatoid arthritis, with peak incidence occurring around menopause. Estrogen has major effects on the immune system and is protective against arthritis. We have previously shown that treatment with estrogen inhibits inflammation and joint destruction in murine models of arthritis, although the mechanisms involved remain unclear. Fibroblastic reticular cells (FRCs) are specialized stromal cells that generate the three-dimensional structure of lymph nodes (LNs). FRCs are vital for coordinating immune responses from within LNs and are characterized by the expression of the chemokine CCL19, which attracts immune cells. The aim of this study was to determine whether the influence of estrogen on innate and adaptive immune cells in arthritis is mediated by estrogen signaling in FRCs. Conditional knockout mice lacking estrogen receptor α (ERα) in CCL19-expressing cells (Ccl19-CreERαfl/fl) were generated and tested. Ccl19-CreERαfl/fl mice and littermate controls were ovariectomized, treated with vehicle or estradiol and subjected to the 28-day-long antigen-induced arthritis model to enable analyses of differentiated T- and B-cell populations and innate cells in LNs by flow cytometry. The results reveal that while the response to estradiol treatment in numbers of FRCs per LN is significantly reduced in mice lacking ERα in FRCs, estrogen does not inhibit joint inflammation or markedly affect immune responses in this arthritis model. Thus, this study validates the Ccl19-CreERαfl/fl strain for studying estrogen signaling in FRCs within inflammatory diseases, although the chosen arthritis model is deemed unsuitable for addressing this question.

Estrogen deprivation and estrogen receptor α antagonism decrease DSS colitis in female mice

The association of hormonal contraception with increased risk of inflammatory bowel disease (IBD) observed in females suggests involvement of ovarian hormones, such as estradiol, and the estrogen receptors in the progression of intestinal inflammation. Here, we investigated the effects of prophylactic SERM2 and estradiol supplementation in dextran sulfate sodium-induced colitis using mice with intact ovaries and ovariectomized (OVX) female mice. We found that graded colitis score was threefold reduced in the OVX mice, compared to mice with intact ovaries. Estradiol supplementation, however, aggravated the colitis in OVX mice, increasing the colitis score to a similar level than what was observed in the intact mice. Further, we observed that immune infiltration and gene expression of inflammatory interleukins Il1b, Il6, and Il17a were up to 200-fold increased in estradiol supplemented OVX colitis mice, while a mild but consistent decrease was observed by SERM2 treatment in intact animals. Additionally, cyclo-oxygenase 2 induction was increased in the colon of colitis mice, in correlation with increased serum estradiol levels. Measured antagonist properties of SERM2, together with the other results presented here, indicates an exaggerating role of ERα signaling in colitis. Our results contribute to the knowledge of ovarian hormone effects in colitis and encourage further research on the potential use of ER antagonists in the colon, in order to alleviate inflammation.