Opposing effects of estradiol and progesterone on the oxidative stress-induced production of chemokine and proinflammatory cytokines in murine peritoneal macrophages

Addressing Psychosocial Care Needs in Women with Peripheral Artery Disease

PURPOSE OF REVIEW

Peripheral artery disease (PAD) is a growing global epidemic. Women with PAD are at elevated risk of experiencing psychosocial stressors that influence the diagnosis, management, and course of their illness due to unique sex- and gender-based factors.

RECENT FINDINGS

We review existing evidence for increased psychosocial risk in women with PAD with a focus on mood disorders, chronic stress, pain experiences, substance use disorders, health behaviors and illness perceptions, and healthcare access. We discuss how these factors exacerbate PAD symptomatology and lead to adverse outcomes. Existing gaps in women's vascular care are reviewed and potential solutions to bridge these gaps through psychosocial care integration are proposed. Current care paradigms for women's vascular care do not adequately screen for and address psychosocial comorbidities. Clinician education, integration of evidence-based psychological care strategies, implementation of workflows for the management of individuals with PAD and mental health comorbidities, reform to reimbursement structures, and further advocacy are needed in this space. This review provides a construct for integrated behavioral health care for women with PAD and advocates for further integration of care.

Sex-specific differences in cytokine signaling pathways in circulating monocytes of cardiovascular disease patients

BACKGROUND AND AIMS

This study aims to identify sex-specific transcriptional differences and signaling pathways in circulating monocytes contributing to cardiovascular disease.

METHODS AND RESULTS

We generated sex-biased gene expression signatures by comparing male versus female monocytes of coronary artery disease (CAD) patients (n = 450) from the Center for Translational Molecular Medicine-Circulating Cells Cohort. Gene set enrichment analysis demonstrated that monocytes from female CAD patients carry stronger chemotaxis and migratory signature than those from males. We then inferred cytokine signaling activities based on CytoSig database of 51 cytokine and growth factor regulation profiles. Monocytes from females feature a higher activation level of EGF, IFN1, VEGF, GM-CSF, and CD40L pathways, whereas IL-4, INS, and HMGB1 signaling was seen to be more activated in males. These sex differences were not observed in healthy subjects, as shown for an independent monocyte cohort of healthy subjects (GSE56034, n = 485). More pronounced GM-CSF signaling in monocytes of female CAD patients was confirmed by the significant enrichment of GM-CSF-activated monocyte signature in females. As we show these effects were not due to increased plasma levels of the corresponding ligands, sex-intrinsic differences in monocyte signaling regulation are suggested. Consistently, regulatory network analysis revealed jun-B as a shared transcription factor activated in all female-specific pathways except IFN1 but suppressed in male-activated IL-4.

CONCLUSIONS

We observed overt CAD-specific sex differences in monocyte transcriptional profiles and cytokine- or growth factor-induced responses, which provide insights into underlying mechanisms of sex differences in CVD.

Impacts of pregnancy and menopause on COVID-19 severity: a systematic review and meta-analysis of 4.6 million women

BACKGROUND

Corona Virus Disease 2019 (COVID-19) pandemic is still a public health emergency of international concern. However, whether pregnancy and menopause impact the severity of COVID-19 remain unclear.

AIM

This study is performed to investigate the truth.

DESIGN

Study appraisal and synthesis follows PRISMA guideline. Meta-analysis is performed in random-effects model.

METHODS

PubMed, Embase, Cochrane database, Central, CINAHL, ClinicalTrials.gov, WHO COVID-19 database and WHO-ICTRP are searched until 28 March 2023.

RESULTS

In total, 57 studies (4 640 275 COVID-19 women) were analyzed. Pregnant women were at a lower risk of severe COVID-19, intensive care unit (ICU) admission and disease mortality compared to those nonpregnant women with comparable comorbidities. In contrast, pregnant women with more prepregnancy comorbidities were at a higher risk of severe COVID-19, ICU admission and invasive mechanical ventilation (IMV). In addition, pregnant women with pregnancy complications had a significantly increased risk of severe COVID-19 and ICU admission. Menopause increased COVID-19 severity, IMV requirement and disease mortality. Hormone replacement therapy inhibited COVID-19 severity in postmenopausal women. Premenopausal and postmenopausal women had a lower chance of severe illness than age-matched men. The impact of pregnancy on COVID-19 severity was significant in Americans and Caucasians, whereas the effect of menopause on COVID-19 severity was only significant in Chinese.

CONCLUSIONS

Pregnancy and menopause are protective and risk factors for severe COVID-19, respectively. The protective role of pregnancy on COVID-19 is minimal and could be counteracted or masked by prepregnancy or pregnancy comorbidities. The administration of estrogen and progesterone may prevent severe COVID-19.

Immunomodulatory role of estrogen in ischemic stroke: neuroinflammation and effect of sex

Although estrogen is predominantly related to the maintenance of reproductive functioning in females, it mediates various physiological effects in nearly all tissues, especially the central nervous system. Clinical trials have revealed that estrogen, especially 17β-estradiol, can attenuate cerebral damage caused by an ischemic stroke. One mechanism underlying this effect of 17β-estradiol is by modulating the responses of immune cells, indicating its utility as a novel therapeutic strategy for ischemic stroke. The present review summarizes the effect of sex on ischemic stroke progression, the role of estrogen as an immunomodulator in immune reactions, and the potential clinical value of estrogen replacement therapy. The data presented here will help better understand the immunomodulatory function of estrogen and may provide a basis for its novel therapeutic use in ischemic stroke.

Sex and gender differences in myocarditis and dilated cardiomyopathy: An update

In the past decade there has been a growing interest in understanding sex and gender differences in myocarditis and dilated cardiomyopathy (DCM), and the purpose of this review is to provide an update on this topic including epidemiology, pathogenesis and clinical presentation, diagnosis and management. Recently, many clinical studies have been conducted examining sex differences in myocarditis. Studies consistently report that myocarditis occurs more often in men than women with a sex ratio ranging from 1:2-4 female to male. Studies reveal that DCM also has a sex ratio of around 1:3 women to men and this is also true for familial/genetic forms of DCM. Animal models have demonstrated that DCM develops after myocarditis in susceptible mouse strains and evidence exists for this progress clinically as well. A consistent finding is that myocarditis occurs primarily in men under 50 years of age, but in women after age 50 or post-menopause. In contrast, DCM typically occurs after age 50, although the age that post-myocarditis DCM occurs has not been investigated. In a small study, more men with myocarditis presented with symptoms of chest pain while women presented with dyspnea. Men with myocarditis have been found to have higher levels of heart failure biomarkers soluble ST2, creatine kinase, myoglobin and T helper 17-associated cytokines while women develop a better regulatory immune response. Studies of the pathogenesis of disease have found that Toll-like receptor (TLR)2 and TLR4 signaling pathways play a central role in increasing inflammation during myocarditis and in promoting remodeling and fibrosis that leads to DCM, and all of these pathways are elevated in males. Management of myocarditis follows heart failure guidelines and there are currently no disease-specific therapies. Research on standard heart failure medications reveal important sex differences. Overall, many advances in our understanding of the effect of biologic sex on myocarditis and DCM have occurred over the past decade, but many gaps in our understanding remain. A better understanding of sex and gender effects are needed to develop disease-targeted and individualized medicine approaches in the future.

Inflammatory Basis of Atherosclerosis: Modulation by Sex Hormones

Atherosclerosis-related cardiovascular diseases (CVDs) are the leading cause of death globally. Several lines of evidence are supportive of the contributory role of vascular inflammation in atherosclerosis. Diverse immune cell types, including monocytes/macrophages, T-cells and neutrophils, as well as specialized proresolving lipid mediators, have been successfully characterized as key players in vascular inflammation. The increased prevalence of atherosclerotic CVD in men in comparison to age-matched premenopausal women and the abolition of sex differences in prevalence during menopause strongly suggest a pivotal role of sex hormones in the development of CVD. Indeed, many animal and human studies conclusively implicate sex hormones as a crucial component in driving the immune response. This is further corroborated by the effective identification of sex hormone receptors in vascular endothelial cells, vascular smooth muscle cells and immune cells. Collectively, these findings suggest a cellular communication between sex hormones and vascular or immune cells underlying the vascular inflammation in atherosclerosis. The aim of this review is to provide an overview of vascular inflammation as a causal cue underlying atherosclerotic CVDs within the context of the modulatory effects of sex hormones. Moreover, the cellular and molecular signaling pathways underlying the sex hormones- immune system interactions as potential culprits for vascular inflammation are highlighted with detailed and critical discussion. Finally, the review concludes by speculations on the potential sex-related efficacy of currently available immunotherapies in mitigating vascular inflammation. Conceivably, a deeper understanding of the immunoregulatory influence of sex hormones on vascular inflammation-mediated atherosclerosis permits sex-based management of atherosclerosis-related CVDs.

C-C motif chemokine receptor 2 as a novel intermediate in the ovulatory cascade

Expression of immune function genes within follicle cells has been reported in ovaries from many species. Recent work from our laboratory showed a direct effect of the monocyte chemoattractant protein 1/C-C motif chemokine receptor 2 system within the feline cumulus oocyte complex, by increasing the mRNA levels of key genes involved in the ovulatory cascade in vitro. Studies were designed to evaluate if C-C motif chemokine receptor 2 acts as a novel mediator of the ovulatory cascade in vitro. Therefore, feline cumulus oocyte complexes were cultured in the presence or absence of a highly selective C-C motif chemokine receptor 2 antagonist together with known inducers of cumulus-oocyte expansion and/or oocyte maturation to assess mRNA expression of key genes related to periovulatory events in other species as well as oocyte maturation. Also, the effects of recombinant monocyte chemoattractant protein 1 on spontaneous or gonadotrophin-induced oocyte maturation were assessed. This is an in vitro system using isolated cumulus oocyte complexes from feline ovaries. The present study reveals the modulation of several key ovulatory genes by a highly selective C-C motif chemokine receptor 2 antagonist. However, this antagonist was not enough to block the oocyte maturation induced by gonadotropins or amphiregulin. Nonetheless, recombinant monocyte chemoattractant protein 1 had a significant effect on spontaneous oocyte maturation, increasing the percentage of metaphase II stage oocytes in comparison to the control. This is the first study in any species to establish C-C motif chemokine receptor 2 as a mediator of some actions of the mid-cycle gonadotrophin surge.

Interactions between inflammation and female sexual desire and arousal function

PURPOSE OF REVIEW

To describe the current state of research on interactions between inflammation and female sexual function.

RECENT FINDINGS

Inflammation may interfere with female sexual desire and arousal via direct (neural) and indirect (endocrine, vascular, social/behavioral) pathways. There are significant sex differences in the effect of inflammation on sexual function, arising from different evolutionary selection pressures on regulation of reproduction. A variety of inflammation-related conditions are associated with risk of female sexual dysfunction, including cardiovascular disease, metabolic syndrome, and chronic pain.

SUMMARY

Clinical implications include the need for routine assessment for sexual dysfunction in patients with inflammation-related conditions, the potential for anti-inflammatory diets to improve sexual desire and arousal function, and consideration of chronic inflammation as moderator of sexual effects of hormonal treatments. Although the evidence points to a role for inflammation in the development and maintenance of female sexual dysfunction, the precise nature of these associations remains unclear.

Beneficial and Deleterious Effects of Female Sex Hormones, Oral Contraceptives, and Phytoestrogens by Immunomodulation on the Liver

The liver is considered the laboratory of the human body because of its many metabolic processes. It accomplishes diverse activities as a mixed gland and is in continuous cross-talk with the endocrine system. Not only do hormones from the gastrointestinal tract that participate in digestion regulate the liver functions, but the sex hormones also exert a strong influence on this sexually dimorphic organ, via their receptors expressed in liver, in both health and disease. Besides, the liver modifies the actions of sex hormones through their metabolism and transport proteins. Given the anatomical position and physiological importance of liver, this organ is evidenced as an immune vigilante that mediates the systemic immune response, and, in turn, the immune system regulates the hepatic functions. Such feedback is performed by cytokines. Pro-inflammatory and anti-inflammatory cytokines are strongly involved in hepatic homeostasis and in pathological states; indeed, female sex hormones, oral contraceptives, and phytoestrogens have immunomodulatory effects in the liver and the whole organism. To analyze the complex and interesting beneficial or deleterious effects of these drugs by their immunomodulatory actions in the liver can provide the basis for either their pharmacological use in therapeutic treatments or to avoid their intake in some diseases.

Immunomodulatory effects of progesterone and selective ligands of membrane progesterone receptors

Progesterone (P4) and its analogues regulate various reproductive processes, such as ovulation, implantation, pregnancy maintenance and delivery. In these processes, an important role is played by the immune cells recruited to the female reproductive organs and tissues, where they are exposed to the action of P4. Progestins regulate cellular processes, acting through nuclear steroid receptors (nSRs), membrane P4 receptors (mPRs), and through the sensors. It remains unclear, what type of receptors is used by P4 and its derivatives to exert their effect on the immune cells and how similar their effects are in different types of these cells. We have previously synthesized new progesterone derivatives, among which two selective mPRs ligands, not interacting with nSRs were identified. The objective of this study was to examine the effects of P4 and new selective mPRs ligands on the expression of pro- and anti-inflammatory cytokines in activated human peripheral blood mononuclear cells (PBMCs), THP-1 monocyte cells, and Jurkat T cells. It was demonstrated that the action of P4 and selective ligands was unidirectional, but in different types of the immune cells, their effects were different, and sometimes even opposite. In PBMCs, exposure to these steroids resulted in the increase of mRNA and secreted protein levels of IL-1β, TNFα, and IL-6 cytokines, as well as in the increase of INFγ mRNA level, decrease of IL-2 mRNA level, increase of TGFβ mRNA level, and decrease of IL-4 mRNA and IL-10 secreted protein levels. In monocytes, similarly to PBMCs, expression of IL-1β and TNFα mRNA was increased, but expression of IL-10 was also increased, and the TGFβ expression statistically significantly remained the same. In Jurkat T cells, expression of IL-2 and TNFα mRNA decreased, while expression of IL-10 increased, and expression of TGFβ did not change. Thus, progestins act on the immune cells through mPRs and have both pro- and anti-inflammatory effects, depending on the phenotypes of these cells. The data obtained are important for understanding the complexity of the immune system regulation by progestins, which depends on the type of the immune cells and individual characteristics of the immune system.

Sex differences in pulmonary arterial hypertension: role of infection and autoimmunity in the pathogenesis of disease

Registry data worldwide indicate an overall female predominance for pulmonary arterial hypertension (PAH) of 2–4 over men. Genetic predisposition accounts for only 1–5% of PAH cases, while autoimmune diseases and infections are closely linked to PAH. Idiopathic PAH may include patients with undiagnosed autoimmune diseases based on the relatively high presence of autoantibodies in this group. The two largest PAH registries to date report a sex ratio for autoimmune connective tissue disease-associated PAH of 9:1 female to male, highlighting the need for future studies to analyze subgroup data according to sex. Autoimmune diseases that have been associated with PAH include female-dominant systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, Sjögren’s syndrome, and thyroiditis as well as male-dominant autoimmune diseases like myocarditis which has been linked to HIV-associated PAH. The sex-specific association of PAH to certain infections and autoimmune diseases suggests that sex hormones and inflammation may play an important role in driving the pathogenesis of disease. However, there is a paucity of data on sex differences in inflammation in PAH, and more research is needed to better understand the pathogenesis underlying PAH in men and women. This review uses data on sex differences in PAH and PAH-associated autoimmune diseases from registries to provide insight into the pathogenesis of disease.

The pulmonary inflammatory response to multiwalled carbon nanotubes is influenced by gender and glutathione synthesis

Inhalation of multiwalled carbon nanotubes (MWCNTs) during their manufacture or incorporation into various commercial products may cause lung inflammation, fibrosis, and oxidative stress in exposed workers. Some workers may be more susceptible to these effects because of differences in their ability to synthesize the major antioxidant and immune system modulator glutathione (GSH). Accordingly, in this study we examined the influence of GSH synthesis and gender on MWCNT-induced lung inflammation in C57BL/6 mice. GSH synthesis was impaired through genetic manipulation of Gclm, the modifier subunit of glutamate cysteine ligase, the rate-limiting enzyme in GSH synthesis. Twenty-four hours after aspirating 25µg of MWCNTs, all male mice developed neutrophilia in their lungs, regardless of Gclm genotype. However, female mice with moderate (Gclm heterozygous) and severe (Gclm null) GSH deficiencies developed significantly less neutrophilia. We found no indications of MWCNT-induced oxidative stress as reflected in the GSH content of lung tissue and epithelial lining fluid, 3-nitrotyrosine formation, or altered mRNA or protein expression of several redox-responsive enzymes. Our results indicate that GSH-deficient female mice are rendered uniquely susceptible to an attenuated neutrophil response. If the same effects occur in humans, GSH-deficient women manufacturing MWCNTs may be at greater risk for impaired neutrophil-dependent clearance of MWCNTs from the lung. In contrast, men may have effective neutrophil-dependent clearance, but may be at risk for lung neutrophilia regardless of their GSH levels.

Assessment of TNFA polymorphisms at positions -857 and -863 in Polish peptic ulcer patients

PURPOSE

Peptic ulceration connected with chronic inflammation in gastrointestinal mucosa could be induced by Helicobacter pylori infection. Tumor necrosis factor alpha (TNF-α) encoded by TNFA gene is a key mediator in the inflammation process. There are several polymorphisms in the promoter of TNFA influencing its transcriptional activity. -857C>T (rs1799724) and -863C>A (rs1800630) substitutions may be responsible for increased TNFA transcription and TNF-α production. The association of these two polymorphisms with peptic ulceration and the development of H. pylori infection in peptic ulcer patients in Poles were evaluated.

MATERIAL AND METHODS

Polymorphisms were assessed by PCR-RFLP in 203 peptic ulcer patients. H. pylori infection was confirmed by rapid urease test. The results of genotyping were compared with those obtained for 248 healthy Polish individuals.

RESULTS

There were no significant differences in genotype and allele frequencies for both investigated polymorphisms between peptic ulcer patients and healthy individuals. No associations between frequencies of particular genotypes and alleles for both SNPs and the presence of H. pylori infection in peptic ulcer patients and in subgroups of peptic ulcer women and men were confirmed.

CONCLUSIONS

The investigated SNPs are not risk factors for peptic ulcer development. They are not risk factors for H. pylori infection in ulcer patients.

Female Sex Hormones Pattern and Its Relation to Disease Severity and Treatment in Pre- and Postmenopausal Patients with Chronic Hepatitis C Virus (Genotype 4) Infection

Chronic hepatitis C (CHC) course revealed differences between men and women. Male gender and postmenopausal women are thought to be of the critical factors affecting HCV infection progression. The study aimed to assess female sex hormones and their relation to disease severity and treatment in HCV infected females. Subjects were divided to 2 groups: 44 CHC female patients and 44 controls. Both groups were classified to premenopausal and postmenopausal females. Serum estradiol (E2), progesterone (PRG), and total testosterone (TT) were assessed using chemiluminescent immunoassay. Our results showed that menopausal patients had significantly higher levels of estradiol, total testosterone, and progesterone compared to controls (P < 0.001). Reproductive aged patients had lower level of total testosterone compared to menopausal patients (P < 0.001). HCV infected females of reproductive age had higher level of progesterone compared to menopausal HCV infected females (P = 0.0014). Indicators of disease severity and treatment response were significantly worse in menopausal women compared to reproductive aged women (fibrosis: P < 0.001, activity: P = 0.045, and treatment: P < 0.001). We observed that lower estradiol level may be related to fibrosis severity in CHC females. Higher total testosterone and progesterone levels may be related to fibrosis severity and poor response to treatment in CHC menopausal females only.

Redox proteomics of the inflammatory secretome identifies a common set of redoxins and other glutathionylated proteins released in inflammation, influenza virus infection and oxidative stress

Protein cysteines can form transient disulfides with glutathione (GSH), resulting in the production of glutathionylated proteins, and this process is regarded as a mechanism by which the redox state of the cell can regulate protein function. Most studies on redox regulation of immunity have focused on intracellular proteins. In this study we have used redox proteomics to identify those proteins released in glutathionylated form by macrophages stimulated with lipopolysaccharide (LPS) after pre-loading the cells with biotinylated GSH. Of the several proteins identified in the redox secretome, we have selected a number for validation. Proteomic analysis indicated that LPS stimulated the release of peroxiredoxin (PRDX) 1, PRDX2, vimentin (VIM), profilin1 (PFN1) and thioredoxin 1 (TXN1). For PRDX1 and TXN1, we were able to confirm that the released protein is glutathionylated. PRDX1, PRDX2 and TXN1 were also released by the human pulmonary epithelial cell line, A549, infected with influenza virus. The release of the proteins identified was inhibited by the anti-inflammatory glucocorticoid, dexamethasone (DEX), which also inhibited tumor necrosis factor (TNF)-α release, and by thiol antioxidants (N-butanoyl GSH derivative, GSH-C4, and N-acetylcysteine (NAC), which did not affect TNF-α production. The proteins identified could be useful as biomarkers of oxidative stress associated with inflammation, and further studies will be required to investigate if the extracellular forms of these proteins has immunoregulatory functions.

Sex differences in inflammation during atherosclerosis

Atherosclerosis is the leading cause of death in the United States and worldwide, yet more men die from atherosclerosis than women, and at a younger age. Women, on the other hand, mainly develop atherosclerosis following menopause, and particularly if they have one or more autoimmune diseases, suggesting that the immune mechanisms that increase disease in men are different from those in women. The key processes in the pathogenesis of atherosclerosis are vascular inflammation, lipid accumulation, intimal thickening and fibrosis, remodeling, and plaque rupture or erosion leading to myocardial infarction and ischemia. Evidence indicates that sex hormones alter the immune response during atherosclerosis, resulting in different disease phenotypes according to sex. Women, for example, respond to infection and damage with increased antibody and autoantibody responses, while men have elevated innate immune activation. This review describes current knowledge regarding sex differences in the inflammatory immune response during atherosclerosis. Understanding sex differences is critical for improving individualized medicine.

Effects of High Estrogen Levels on Monocyte Chemoattractant Protein-1 and Wound Healing

Objective: Herein, we tested the effects of high levels of supplemental estrogen treatment on cutaneous wound healing. Approach: Female mice were implanted with a 17β-estradiol (E₂) secreting pellet or placebo before receiving a full-thickness dermal excisional wound. Mice receiving the E₂ pellet attained hormone levels that are comparable to those achieved during pregnancy. At 1, 3, and 5 days after injury, the dermal excision wound was examined for their histologic appearance, rate of closure, and chemokine levels. Results: Wound closure, assessed by percent reepithelialization, was slower in E₂-treated mice relative to placebo (42.6%±6.6% vs. 70.0%±5.3%, respectively, 3 days after injury). In addition, there was a marked reduction in the subepithelial inflammatory infiltrate and granulation tissue in E₂-treated mice relative to placebo. Wound levels of monocyte chemoattractant protein-1 (MCP-1) were increased by 3 days after injury and continued to rise at 5 days after injury in placebo-treated mice (p<0.01). By contrast, MCP-1 levels were significantly reduced at 3 and 5 days after injury in E₂-treated mice relative to placebo-treated controls (p<0.01). This attenuation could be reversed by treatment with an estrogen receptor antagonist. Innovation: High levels of estrogen are able to suppress normal wound closure. Conclusion: Dermal wound healing can be altered by manipulating the gonadal steroid hormone levels. In particular, high levels of estrogen can be utilized to slow down the rate of wound healing through a reduction in the inflammatory response.

Sex-specific association of estrogen receptor 2 polymorphisms with hepatitis C virus infection outcomes in a high-risk Chinese Han population

Hepatitis C virus (HCV) has different clinical and biological characteristics in women versus men, which suggests the potential involvement of estrogen. Estrogen signaling is mediated by the estrogen receptor, and genetic variations in the estrogen receptor gene might affect the pathology of HCV infection. We performed logistic regression analysis to explore the associations between rs1256049, rs4986938 and rs944459 polymorphisms of the estrogen receptor 2 gene (ESR2) and HCV infection outcomes. The variant A allele of rs4986938 was associated with an increased HCV infection susceptibility in the males (additive model: adjusted OR=1.493, P=0.010) and a significantly reduced risk of HCV infection in the female subgroup (GA vs. GG: adjusted OR=0.710, P=0.012; dominant model: adjusted OR=0.686, P=0.004; additive model: adjusted OR=0.703, P=0.002). In addition, females carrying the rs4986938 AA genotype appeared to clear HCV spontaneously more readily (adjusted OR=0.237, P=0.011), and additive model analyses showed that each additional allele contributed a decreased risk of approximately 34% for HCV chronicity (adjusted OR=0.659, P=0.006). Furthermore, a significant multiplicative interaction between the combined rs1256049 and rs4986938 genotypes was found to decrease HCV infection risk (adjusted OR=0.583, P=3.000×10(-4)). The area under the curve, based on the model and including age, gender, HCV genotypes and the three SNPs, was significantly related to the clearance of HCV (P=0.003). We provide here the first report that rs4986938 in the ESR2 gene played a potential sex-specific role in the etiology of HCV infection in a high-risk Chinese Han population, suggesting that ESR2 is a candidate susceptibility gene for HCV infection and viral clearance.

Ovarian steroid hormone-regulated uterine remodeling occurs independently of macrophages in mice

Macrophages are abundant in the uterine stroma and are intimately juxtaposed with other cell lineages comprising the uterine epithelial and stromal compartments. We postulated that macrophages may participate in mediating or amplifying the effects of ovarian steroid hormones to facilitate the uterine remodeling that is a characteristic feature of every estrus cycle and is essential for pregnancy. Using the Cd11b-Dtr transgenic mouse model with an ovariectomy and hormone replacement strategy, we depleted macrophages to determine their role in hormone-driven proliferation of uterine epithelial and stromal cells and uterine vascular development. Following diphtheria toxin (DT) administration, approximately 85% of EMR1-positive (EMR1⁺) macrophages, as well as 70% of CD11C⁺ dendritic cells, were depleted from Cd11b-Dtr mice. There was no change in bromodeoxyuridine incorporation into epithelial cells induced to proliferate by administration of 17beta-estradiol (E2) to ovariectomized mice or into stromal cells induced to proliferate in response to E2 and progesterone (P4), and the resulting sizes and structures of the luminal epithelial and stromal cell compartments were not altered compared with those of leukocyte replete controls. Depletion of CD11B⁺ myeloid cells failed to alter the density or pattern of distribution of uterine blood vessels, as identified by staining PECAM1-positive endothelial cells in the uterine stroma of E2- or E2 combined with P4 (E2P4)-treated ovariectomized mice. These experiments support the interpretation that macrophages are dispensable to regulation of proliferative events induced by steroid hormones in the cycling and early pregnant mouse uterus to establish the epithelial, stromal, and vascular architecture which is critical for normal reproductive competence.

Depression and cardiovascular disease in women: is there a common immunological basis? A theoretical synthesis

Clinical studies have established an inherent comorbidity between depression and the development of cardiovascular disease (CVD). Furthermore, this comorbidity seems to be more amplified in women than in men. To further investigate this comorbidity, a thorough literature review was conducted on studies from 1992 to date. The PubMed database was accessed using the keywords: cardiovascular disease, inflammation, depression, and sex differences. Both human and animal studies were considered. This review takes the standpoint that depression and CVD are both inflammatory disorders, and that their co-occurrence may be related to how the hypothalamic–pituitary–adrenal axis, serotonergic transmission and circulation, and the renin–angiotensin–aldosterone system via angiotensin II are affected by the excess secretion of proinflammatory cytokines. More recently, preliminary research attributes this systemic inflammation to a global deficiency in CD4+CD25+FOXP3 regulatory T cells. 17-β estradiol and progesterone mediated modulation of cytokine secretion may partially explain the sex differences observed. These hormones and reproductive events associated with hormonal fluctuations are discussed in depth, including the analysis of perinatal models of depression and CVD, including preeclampsia. However, as evidenced by this review, there is a need for mechanistic research in humans to truly understand the nature and directionality of the relationship between depression and CVD.

Hepatoprotective effect of tamoxifen on steatosis and non-alcoholic steatohepatitis in mouse models

Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic lipid accumulation that starts with steatosis and progresses to non-alcoholic steatohepatitis (NASH). Recently, the number of patients with such liver diseases has increased, but the understanding of the fundamental mechanisms and appropriate therapies are lacking. Tamoxifen (TAM) is a selective estrogen receptor modulator. We previously reported that TAM plays a protective role against drug-induced and chemical-induced acute liver injuries. However, the effects of TAM on chronic liver injury, including steatosis and NASH, remain to be addressed. We first found that the administration of TAM to mouse models of steatosis and NASH significantly decreased the plasma ALT and AST levels. The administration of TAM decreased the accumulated fat and inflammation in the livers in both mouse models. In addition, we observed decreased hepatic mRNA levels of triglyceride synthesis, acyl-CoA: diacylglycerol acyltransferase 2 (DGAT2), proinflammatory cytokines, tumor necrosis factor (TNF) α, and chemokines, monocyte chemoattractant protein (MCP) -1. TAM increased the extracellular signal-regulated kinase (ERK) phosphorylation, which is related to the proliferation and regeneration of liver and to decreased DGAT2 gene expression. Furthermore, a decrease in eukaryotic translational initiation factor (eIF2α), which is involved in apoptosis, was observed in both models. These findings suggest that TAM treatment exerts a hepatoprotective effect against steatosis and NASH, presumably via up-regulation of the ERK pathways and attenuation of eIF2α activation. These pathways represent a potential therapeutic target for steatosis and NASH in drug development.

Sex, stroke, and inflammation: the potential for estrogen-mediated immunoprotection in stroke

Stroke is the third leading cause of death and the primary cause of disability in the developed world. Experimental and clinical data indicate that stroke is a sexually dimorphic disease, with males demonstrating an enhanced intrinsic sensitivity to ischemic damage throughout most of their lifespan. The neuroprotective role of estrogen in the female brain is well established, however, estrogen exposure can also be deleterious, especially in older women. The mechanisms for this remain unclear. Our current understanding is based on studies examining estrogen as it relates to neuronal injury, yet cerebral ischemia also induces a robust sterile inflammatory response involving local and systemic immune cells. Despite the potent anti-inflammatory effects of estrogen, few studies have investigated the contribution of estrogen to sex differences in the inflammatory response to stroke. This review examines the potential role for estrogen-mediated immunoprotection in ischemic injury.

Sex-associated expression of co-stimulatory molecules CD80, CD86, and accessory molecules, PDL-1, PDL-2 and MHC-II, in F480+ macrophages during murine cysticercosis

Macrophages are critically involved in the interaction between T. crassiceps and the murine host immune system. Also, a strong gender-associated susceptibility to murine cysticercosis has been reported. Here, we examined the sex-associated expression of molecules MHC-II, CD80, CD86, PD-L1, and PD-L2 on peritoneal F4/80^hi macrophages of BALB/c mice infected with Taenia crassiceps. Peritoneal macrophages from both sexes of mice were exposed to T. crassiceps total extract (TcEx). BALB/c Females mice recruit higher number of macrophages to the peritoneum. Macrophages from infected animals show increased expression of PDL2 and CD80 that was dependent from the sex of the host. These findings suggest that macrophage recruitment at early time points during T. crassiceps infection is a possible mechanism that underlies the differential sex-associated susceptibility displayed by the mouse gender.

Modulation of temporomandibular joint nociception and inflammation in male rats after administering a physiological concentration of 17β-oestradiol

BACKGROUND

Previous studies have shown 17β-estradiol will reduce temporomandibular joint (TMJ) inflammation and hypersensitivity in female rats. Although male rats contain significant amounts of oestradiol, it was unknown whether a physiological concentration of 17β-estradiol would attenuate male TMJ inflammation and nociception.

METHODS

Intact and castrated rats were given a physiological concentration of oestradiol to examine first, if oestradiol will affect male TMJ nociception/inflammation and, second, if administration of oestradiol would act synergistically with endogenous male hormones to attenuate TMJ nociception. The hormonally treated rats were given TMJ injections of complete Freund's adjuvant (CFA) and then nociception was measured using a validated method in which a lengthening in meal duration is directly correlated to the intensity of deep TMJ nociception. Inflammation was assayed by quantitating pro-inflammatory gene expression.

RESULTS

Meal duration was significantly lengthened after TMJ CFA injection and this lengthening was significantly attenuated in the castrated but not intact males after administering a physiological concentration of oestradiol. A physiological concentration of 17β-estradiol also significantly increased IL-6 expression in the inflamed TMJ of castrated males while 17β-estradiol did not alter IL-1β, CXCL2 and CCL20 expression. Castration increased pro-inflammatory mediators IL-6, IL-1β and CXCL2 suggesting male sex hormones were anti-inflammatory. Calcitonin gene-related peptide in the trigeminal ganglia was unchanged.

CONCLUSIONS

Similar to females, male rats with TMJ inflammation showed a reduced nociceptive response after treatment with a physiological concentration of oestradiol suggesting the effects of oestradiol treatment were not constrained by organizational processes in the males.

Mechanism of exacerbative effect of progesterone on drug-induced liver injury

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical drug therapy. However, the underlying mechanism of DILI is little known. It is generally believed that women exhibit worse outcomes from DILI than men. Recently, we found that pretreatment of mice with estradiol attenuated halothane (HAL)-induced liver injury, whereas pretreatment with progesterone exacerbated it in female mice. To investigate the mechanism of sex difference of DILI, we focused on progesterone in this study. We found the exacerbating effect of progesterone in thioacetamide (TA), α-naphthylisothiocyanate, and dicloxacillin-induced liver injury only in female mice. Higher number of myeloperoxidase-positive mononuclear cells infiltrated into the liver and increased levels of Chemokine (C-X-C motif) ligand 1 and 2 (CXCL1 and CXCL2) and intercellular adhesion molecule-1 in the liver were observed. Interestingly, CXCL1 was slightly increased by progesterone pretreatment alone. Progesterone pretreatment increased the extracellular signal-regulated kinase (ERK) phosphorylation in HAL-induced liver injury. Pretreatment with U0126 (ERK inhibitor) significantly suppressed the exacerbating effect of progesterone and the expression of inflammatory mediators. In addition, pretreatment with gadolinium chloride (GdCl(3): inhibitor of Kupffer cells) significantly suppressed the exacerbating effect of progesterone pretreatment and the expression of inflammatory mediators. Moreover, posttreatment of RU486 (progesterone receptor antagonist) 1 h after the HAL or TA administration ameliorated the HAL- or TA-induced liver injury, respectively, in female mice. In conclusion, progesterone exacerbated the immune-mediated hepatotoxic responses in DILI via Kupffer cells and ERK pathway. The inhibition of progesterone receptor and decrease of the immune response may have important therapeutic implications in DILI.

Estrogen deficiency worsens steatohepatitis in mice fed high-fat and high-cholesterol diet

Recent studies indicate an accelerated progression of nonalcoholic steatohepatitis (NASH) in postmenopausal women. Hypercholesterolemia, an important risk factor for NASH progression, is often observed after menopause. This study examined the effects of estrogen on NASH in ovariectomized (OVX) mice fed a high-fat and high-cholesterol (HFHC) diet. To investigate the effects of estrogen deficiency, OVX mice and sham-operated (SO) mice were fed normal chow or HFHC diet for 6 wk. Next, to investigate the effects of exogenous estrogen replenishment, OVX mice fed with HFHC diet were treated with implanted hormone release pellets (containing 17β-estradiol or placebo vehicle) for 6 wk. OVX mice on the HFHC diet showed enhanced liver injury with increased liver macrophage infiltration and elevated serum cholesterol levels compared with SO-HFHC mice. Hepatocyte monocyte chemoattractant protein-1 (MCP1) protein expression in OVX-HFHC mice was also enhanced compared with SO-HFHC mice. In addition, hepatic inflammatory gene expressions, including monocytes chemokine (C-C motif) receptor 2 (CCR2), were significantly elevated in OVX-HFHC mice. Estrogen treatment improved serum cholesterol levels, liver injury, macrophage infiltration, and inflammatory gene expressions in OVX-HFHC mice. Moreover, the elevated expression of liver CCR2 and MCP1 were decreased by estrogen treatment in OVX-HFHC mice, whereas low-density lipoprotein dose dependently enhanced CCR2 expression in THP1 monocytes. Our study demonstrated that estrogen deficiency accelerated NASH progression in OVX mice fed HFHC diet and that this effect was improved by estrogen therapy. Hypercholesterolemia in postmenopausal women would be a potential risk factor for NASH progression.

Evaluation of cytokine expression by blood monocytes of lactating Holstein cows with or without postpartum uterine disease

Whereas neutrophils are the main phagocytic leukocytes, monocytes and macrophages are actively involved in immunomodulation after infection. Recent studies have demonstrated that neutrophil function is impaired by the state of negative energy balance around parturition, and that cows that develop uterine disease have a greater degree of negative energy balance than healthy cows. The objectives of this study were to compare monocyte gene expression and protein secretion of selected cytokines from calving to 42 d after calving in Holstein cows that did or did not develop uterine disease. Real time quantitative RT-PCR (Tumor necrosis factor-α (TNFα), Interleukin (IL)-1β, IL-6, IL-8 and IL-10) and ELISA (TNFα, IL-1β and IL-8) were used to evaluate cytokine response following in vitro stimulation of blood-derived monocytes with irradiated E. coli. Relative to unstimulated cells, E. coli-stimulated monocytes from cows with metritis had lower gene expression of key pro-inflammatory cytokines than healthy cows from calving to 14 d after calving (TNFα at 0, 7, and 14 d after calving, IL-1β and IL-6 at 7 and 14 d after calving; P < 0.05). There were no significant differences between groups for expression of IL-8 or the anti-inflammatory cytokine IL-10. This was due, in part, to higher gene expression in unstimulated monocytes (TNFα, IL-1β, IL-6 and IL-10) in early lactation from cows with metritis. Expression of mRNA in stimulated cells (relative to housekeeping genes) was lower for TNFα (7 and 14 d postpartum) and for IL-10 (7 and 14 d postpartum) in cows with metritis. Concentration of TNFα was lower in the culture medium of E. coli-stimulated monocytes from cows with metritis than healthy cows at calving and 7 and 21 d after calving (P < 0.05). Circulating cytokine concentrations were not different between groups for IL-8 and were below the limits of detection for TNFα and IL-1β. Cytokine gene expression and production were similar between healthy cows and cows that developed endometritis, diagnosed cytologically at 42 d after calving. We concluded that altered levels of expression and production of pro-inflammatory cytokines postpartum could contribute to impaired inflammatory response and predispose cows to development of metritis.

Dual roles for macrophages in ovarian cycle-associated development and remodelling of the mammary gland epithelium

Each ovarian cycle, the mammary gland epithelium rotates through a sequence of hormonally regulated cell proliferation, differentiation and apoptosis. These studies investigate the role of macrophages in this cellular turnover. Macrophage populations and their spatial distribution were found to fluctuate across the cycle. The number of macrophages was highest at diestrus, and the greatest number of macrophages in direct contact with epithelial cells occurred at proestrus. The physiological necessity of macrophages in mammary gland morphogenesis during the estrous cycle was demonstrated in Cd11b-Dtr transgenic mice. Ovariectomised mice were treated with estradiol and progesterone to stimulate alveolar development, and with the progesterone receptor antagonist mifepristone to induce regression of the newly formed alveolar buds. Macrophage depletion during alveolar development resulted in a reduction in both ductal epithelial cell proliferation and the number of alveolar buds. Macrophage depletion during alveolar regression resulted in an increased number of branch points and an accumulation of TUNEL-positive cells. These studies show that macrophages have two roles in the cellular turnover of epithelial cells in the cycling mammary gland; following ovulation, they promote the development of alveolar buds in preparation for possible pregnancy, and they remodel the tissue back to its basic architecture in preparation for a new estrous cycle.

Atherosclerosis and sex hormones: current concepts

CVD (cardiovascular disease) is the leading cause of death for women. Considerable progress has been made in both our understanding of the complexities governing menopausal hormone therapy and our understanding of the cellular and molecular mechanisms underlying hormone and hormone receptor function. Understanding the interplay of atherosclerosis and sex steroid hormones and their cognate receptors at the level of the vessel wall has important ramifications for clinical practice. In the present review, we discuss the epidemiology of CVD in men and women, the clinical impact of sex hormones on CVD, and summarize our current understanding of the pathogenesis of atherosclerosis with a focus on gender differences in CVD, its clinical presentation and course, and pathobiology. The critical animal and human data that pertain to the role of oestrogens, androgens and progestins on the vessel wall is also reviewed, with particular attention to the actions of sex hormones on each of the three key cell types involved in atherogenesis: the endothelium, smooth muscle cells and macrophages. Where relevant, the systemic (metabolic) effects of sex hormones that influence atherogenesis, such as those involving vascular reactivity, inflammation and lipoprotein metabolism, are discussed. In addition, four key current concepts in the field are explored: (i) total hormone exposure time and coronary heart disease risk; (ii) the importance of tissue specificity of sex steroid hormones, critical timing and the stage of atherosclerosis in hormone action; (iii) biomarkers for atherosclerosis with regard to hormone therapy; and (iv) the complex role of sex steroids in inflammation. Future studies in this field will contribute to guiding clinical treatment recommendations for women and help define research priorities.

Sex steroids as inflammatory regulators

It is becoming increasingly clear that endogenous sex steroids are key players in a range of inflammatory contexts. Androgens and estrogens have been shown to have a profound influence on the function of inflammatory cells including macrophages and on the secretion and activation of a range of plasma-borne inflammatory mediators. The menopause and polymorphisms in estrogen receptor genes have separately been shown to affect the incidence of a range of inflammatory disorders. Sex steroids themselves have been shown to be protective in certain conditions; harmful in others. This review will summarize their documented effects on inflammatory processes, with particular focus on two areas that have received much recent attention: the antiatherosclerotic properties of estrogens in females and the wound healing effects of sex steroids.

Rat mesangial cells exhibit sex-specific profibrotic and proinflammatory phenotypes

BACKGROUND

Chronic renal disease progresses more rapidly in males compared to females. This study investigated whether there were any inherent differences between male and female mesangial cells that could contribute to this phenomenon and whether these differences could be modulated by sex hormones.

METHODS

Experiments were carried out on cultured mesangial cells derived from adult male and female Wistar rat kidneys. Fibronectin, TNFalpha and IL-1beta levels were measured in control and macrophage-conditioned medium (MCM)-injured cells in the presence and absence of 17beta estradiol or testosterone.

RESULTS

Male mesangial cells expressed higher baseline fibronectin levels compared to female cells. Similarly, basal levels of the proinflammatory cytokines TNFalpha and IL-1beta were higher in male cells. Fibronectin and IL-1beta levels were enhanced proportionately between the sexes in response to MCM stimulation, whilst the increase in TNFalpha levels was greater in MCM-stimulated female cells. Treatment with 10(-8) M estradiol down-regulated baseline fibronectin levels in female mesangial cells but had no effect on basal levels in male cells. Estradiol had no effect on MCM-stimulated fibronectin levels in female mesangial cells but further increased stimulated levels in male cells. Testosterone had no effect on basal fibronectin levels of either sex but further enhanced MCM-stimulated fibronectin levels in mesangial cells of both sexes. Sex hormone treatment had no effect on cytokine levels in male mesangial cells. However, in female cells estradiol decreased TNFalpha levels and increased IL-1beta levels, while testosterone increased the levels of both cytokines.

CONCLUSION

These data would suggest that male mesangial cells inherently exhibit greater profibrotic and proinflammatory characteristics than female cells. The inherent gender phenotypes are further modulated by sex hormones. This sexual dimorphism in mesangial cells may play a contributory role in the faster rate of progression to end-stage renal disease in males.

Dietary calcium and dairy modulation of oxidative stress and mortality in aP2-agouti and wild-type mice

Oxidative and inflammatory stress have been implicated as major contributors to the aging process. Dietary Ca reduced both factors in short-term interventions, while milk exerted a greater effect than supplemental Ca. In this work, we examined the effects of life-long supplemental and dairy calcium on lifespan and life-span related biomarkers in aP2-agouti transgenic (model of diet-induced obesity) and wild-type mice fed obesigenic diets until their death. These data demonstrate that dairy Ca exerts sustained effects resulting in attenuated adiposity, protection against age-related muscle loss and reduction of oxidative and inflammatory stress in both mouse strains. Although these effects did not alter maximum lifespan, they did suppress early mortality in wild-type mice, but not in aP2-agouti transgenic mice.

Effects of estradiol and progesterone on the proinflammatory cytokine production by mononuclear cells from patients with chronic hepatitis C

AIM: To investigate the effects of estradiol (E2) and progesterone on the unstimulated and oxidative stress-stimulated production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, and macrophage chemotactic protein (MCP)-1 by peripheral blood mononuclear cells (PBMCs) from patients with chronic hepatitis C and healthy controls.

METHODS: The PBMCs were separated from age-matched 72 males and 71 females with and without chronic hepatitis C, who were divided into two groups based on a mean menopausal age of 50 years. Oxidative stress was induced by hydrogen peroxide in the cells incubated in serum-free media. Cytokines in the culture supernatant were measured by an enzyme-linked immunosorbent assay.

RESULTS: The highest levels of the spontaneous production of TNF-α, IL-1β, IL-8, and MCP-1 by the unstimulated PBMCs were in the older male patients with chronic hepatitis C and the lowest levels were in the pre-menopausal female healthy controls. E2 inhibited the cytokine production by the unstimulated PBMCs from the older male and post-menopausal female patients, which was further stimulated by progesterone. The exposure to hydrogen peroxide in the PBMCs from the younger male and pre-menopausal female healthy subjects induced the production of cytokines. The change rates of the hydrogen peroxide-stimulated cytokine production were suppressed by E2 and enhanced by progesterone.

CONCLUSION: These findings suggest that E2 may play a favorable role in the course of persistent liver injury by preventing the accumulation of monocytes-macrophages and by inhibiting proinflammatory cytokine production, whereas progesterone may counteract the favorable E2 effects.