Estrogen receptor α gene polymorphism and vascular complications in girls with type 1 diabetes mellitus

Considering hormones as sex- and gender-related factors in biomedical research: Challenging false dichotomies and embracing complexity

The inclusion of sex and gender considerations in biomedicine has been increasing in light of calls from research and funding agencies, governmental bodies, and advocacy groups to direct research attention to these issues. Although the inclusion of both female and male participants is often an important element, overreliance on a female-male binary tends to oversimplify the interactions between sex- and gender-related factors and health, and runs a risk of being influenced by cultural stereotypes about sex and gender. When biomedical researchers are examining how hormones associated with gender and sex may influence pathways of interest, it is of crucial importance to approach this work with a critical lens on the rhetoric used, and in ways that acknowledge the complexity of hormone physiology. Here, we document the ways in which discourses around sex, gender and hormones shape our scientific thinking and practice in biomedical research, and review how the existing scientific knowledge about hormones reflects a complex and dynamic reality that is often not reflected outside of specialist niches of hormone biology. Where biomedical scientists take up sex- and gender-associated hormones as a way of addressing sex and gender considerations, it is valuable for us to bring a critical lens to the rhetoric and discourses used, to employ a sex contextualist approach in designing experimentation, and be rigorous and reflexive about the approaches used in analysis and interpretation of data. These strategies will allow us to design experimentation that goes beyond binaries, and grapples more directly with the material intricacies of sex, gender, and hormones.

A Low Dose of Ouabain Alters the Metabolic Profile of Adult Rats Experiencing Intrauterine Growth Restriction in a Sex-Specific Manner

Intrauterine growth restriction (IUGR) increases the risk of type 2 diabetes mellitus (T2DM) and metabolic diseases. The pancreas of fetuses with IUGR is usually characterized by pancreatic dysplasia and reduced levels of insulin secretion caused by the diminished replication of β-cells. Previous studies showed that a low dose of ouabain could reduce the apoptosis of embryonic nephric cells during IUGR and partially restore the number of nephrons at birth. The rescued kidneys functioned well and decreased the prevalence of hypertension. Thus, we hypothesized that ouabain could rescue pancreatic development during IUGR and reduce the morbidity of T2DM and metabolic diseases. Maternal malnutrition was used to induce the IUGR model, and then a low dose of ouabain was administered to rats with IUGR during pregnancy. Throughout the experiment, we monitored the pattern of weight increase and evaluated the metabolic parameters in the offspring in different stages. Male, but not female, offspring in the IUGR group presented catch-up growth. Ouabain could benefit the impaired glucose tolerance of male offspring; however, this desirable effect was eliminated by aging. The insulin sensitivity was significantly impaired in male offspring with IUGR, but it was improved by ouabain, even during old age. However, in the female offspring, low birth weight appeared to be a beneficial factor even in old age; administering ouabain exacerbated these favorable effects. Our data suggested that IUGR influenced glucose metabolism in a sex-specific manner and ouabain treatment during pregnancy exerted strongly contrasting effects in male and female rats.

Sex-dependent effects on the gut microbiota and host metabolome in type 1 diabetic mice

Sexual dimorphism exists in the onset and development of type 1 diabetes (T1D), but its potential pathological mechanism is poorly understood. In the present study, we examined sex-specific changes in the gut microbiome and host metabolome of T1D mice via 16S rRNA gene sequencing and nuclear magnetic resonance (NMR)-based metabolomics approach, and aimed to investigate potential mechanism of the gut microbiota-host metabolic interaction in the sexual dimorphism of T1D. Our results demonstrate that female mice had a greater shift in the gut microbiota than male mice during the development of T1D; however, host metabolome was more susceptible to T1D in male mice. The correlation network analysis indicates that T1D-induced host metabolic changes may be regulated by the gut microbiota in a sex-specific manner, mainly involving short-chain fatty acids (SCFAs) metabolism, energy metabolism, amino acid metabolism, and choline metabolism. Therefore, our study suggests that sex-dependent "gut microbiota-host metabolism axis" may be implicated in the sexual dimorphism of T1D, and the link between microbes and metabolites might contribute to the prevention and treatment of T1D.

Antimicrobial photodynamic therapy (aPDT) with curcumin controls intradermal infection by Staphylococcus aureus in mice with type 1 diabetes mellitus: a pilot study

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main pathogens that cause infections in diabetic individuals. In this paper, we report the outcomes of our investigation on the intradermal application of antimicrobial photodynamic therapy (PDT) with curcumin in an infection induced by MRSA ATCC 43300 strain in the ear of mice with Type 1 Diabetes Mellitus (T1DM). A solution containing 100 μg of curcumin was photoactivated ex vivo with a LED light (450 nm) delivering a fluency of 13.5 J/cm³. This solution was administered in the ear intradermally, at the same inoculum site as the MRSA ATCC 43300 strain (PDT Group). This study also included the use of two control groups (both infected): One was treated with saline and the other was treated with non-photoactivated curcumin. The animals were euthanized 24 h after these treatments and samples of draining lymph node and treated ear were collected for examination. The PDT group showed lower bacterial load in the draining lymph node when compared to the saline and curcumin groups (p-value <0.05) 24 h after treatment. In addition to bacterial load, the PDT group presented a higher concentration of nitrates and nitrites in the draining lymph node when compared to the saline and curcumin groups (p-value <0.001). Examining the infectious site, despite apparently having similar inflammatory cell recruitment compared with the control groups, the PDT group showed a profile with less intense activity in the myeloperoxidase expression when compared to the saline group (p-value <0.001). Additionally, the detected concentration of cytokines such as IL-1β, IL-12, and IL-10 was significantly lower in the PDT group when compared to the saline group (p-value <0.01; p-value <0.05; p-value <0.05, respectively), thus presenting a less intense inflammatory response during infection resolution. Our pilot study showed for the first time the therapeutic potential of PDT using curcumin when administered intradermally in the treatment of infections caused by S. aureus in mice with T1DM.

Characterization of immune pleiotropy of ESR1 gene in pigs

It is well known that the estrogen receptor alpha gene (ESR1) affects the reproductive traits of pigs; however, the immune role of ESR1 gene has not yet been resolved. Here, we characterized the pleiotropic aspects of ESR1 gene in immunity using the pig model. Tissue expression profile showed that the ESR1 gene had a broad ectopic expression in multiple reproductive and immune-related tissues/organs, which provided the tissue-level spatial fundamental of ESR1 gene that might function as a pleiotropic immune regulator. Using the peripheral blood cell model, a coupling transcriptome analytical strategy was proposed and verified that there existed strong positive or negative correlations of ESR1 gene with hundreds of differentially expressed genes that were involved in the immune regulation, indicating that the ESR1 gene might affect or be affected by, directly or indirectly, dozens of immune-related genes in the peripheral blood cells. Furthermore, the results of genetic association analysis showed that the SmaI-polymorphism of ESR1 gene had significant or highly significant associations with multiple immune traits, including platelet (PLT), hematocrit (HCT), the number of CD4-CD8-CD3- cells, plateletcrit (PCT), mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC). Multiple evidences supported the immune pleiotropic roles of ESR1 gene in pigs. The study advances our understanding of the cross-species immune pleiotropic landscape of ESR1 gene and also provides a potential pleiotropic molecular marker for disease-resistant breeding in pigs.

Diabetic vasculopathy: macro and microvascular injury

PURPOSE OF REVIEW

Diabetes is a common and prevalent medical condition as it affects many lives around the globe. Specifically, type-2 Diabetes (T2D) is characterized by chronic systemic inflammation alongside hyperglycemia and insulin resistance in the body, which can result in atherosclerotic legion formation in the arteries and thus progression of related conditions called diabetic vasculopathies. T2D patients are especially at risk for vascular injury; adjunct in many of these patients heir cholesterol and triglyceride levels reach dangerously high levels and accumulate in the lumen of their vascular system.

RECENT FINDINGS

Microvascular and macrovascular vasculopathies as complications of diabetes can accentuate the onset of organ illnesses, thus it is imperative that research efforts help identify more effective methods for prevention and diagnosis of early vascular injuries. Current research into vasculopathy identification/treatment will aid in the amelioration of diabetes-related symptoms and thus reduce the large number of deaths that this disease accounts annually.

SUMMARY

This review aims to showcase the evolution and effects of diabetic vasculopathy from development to clinical disease as macrovascular and microvascular complications with a concerted reference to sex-specific disease progression as well.

Effect of Estrogen Receptor- Alpha Gene Polymorphism (IVS1-397 T>C) on Microvascular Complications of Type 1 Diabetes Mellitus

BACKGROUND

Type 1 diabetes mellitus (T1DM) is an autoimmune disease whose etiology involves genetic predisposition as well as environmental factors. Polymorphisms of some genes are among the most important genetic factors that influence autoimmunity. Gender is another important factor affecting autoimmunity. Females are more susceptible to autoimmune diseases which may be due to the effect of sex hormones on the immune system activity. The metabolic effects of estrogen are mediated through its receptor - alpha. The exact mechanism is not well understood. A number of polymorphisms have been reported in the Estrogen Receptor- alpha (ER-alpha) IVS1 397 T>C gene which may be involved in the pathogenesis of diabetes.

OBJECTIVES

To assess the influence of Estrogen Receptor- alpha gene [IVS1-397 T>C] polymorphism on vascular complications of type1 diabetes mellitus in pubertal females and on the glycemic control.

METHODS

This cross-sectional case-control study included 40 pubertal regularly menstruating girls less than 18 years with type 1 diabetes mellitus recruited from the Pediatric Diabetes Clinic, Children's Hospital, Ain-Shams University and 20 healthy age-and sex-matched controls. Estrogen receptor alpha genotypes were analyzed by Restriction Fragment Length PCR and correlated with both clinical and laboratory parameters in the studied cases. ER-alpha was chosen as it might play a role in diabetes pathogenesis.

RESULTS

The study revealed the TC genotype was the most prevalent genotype of the estrogen receptor. The TT genotype patients had a younger age of onset of T1DM. The prevalence of obesity was higher among TC and TT than in CC bearing patients. In addition, CC genotype patients had the least prevalence of microalbuminuria and had better glycemic control than other genotypes.

CONCLUSION

Our findings suggest that Estrogen receptor- alpha gene may be affecting the age of onset of Type1 diabetes mellitus in pubertal girls as well as the glycemic control of these patients, where CC bearing girls had better glycemic control than other genotypes and less incidence of microalbuminuria.

Estrogen receptor 1 gene polymorphisms (PvuII and XbaI) are associated with type 2 diabetes in Palestinian women

Background

Type 2 diabetes mellitus (T2DM) is a multifactorial disease where both genetic and environmental factors contribute to its pathogenesis. The PvuII and XbaI polymorphisms of the estrogen receptor 1 (ESR1) gene have been variably associated with T2DM in several populations. This association has not been studied in the Palestinian population. Therefore, the aim of this study was to investigate the association between the PvuII and XbaI variants in the ESR1 and T2DM and its related metabolic traits among Palestinian women.

Methods

This case-control study included 102 T2DM and 112 controls in which PvuII and XbaI variants of the ESR1 gene were genotyped using amplicon based next generation sequencing (NGS).

Results

Allele frequencies of both PvuII and XbaI variants were not significantly different between patients and control subjects (P > 0.05). In logestic regression analysis adjusted for age and BMI, the ESR1 PvuII variant was associated with risk of T2DM in three genotypic models (P < 0.025) but the strongest association was observed under over-dominant model (TT+CC vs. TC) (OR = 2.32, CI [1.18-4.55] adjusted P = 0.013). A similar but non-significant trend was also observed for the ESR1 XbaI variant under the over-dominant model (AA+GG vs. AG) (OR = 2.03, CI [1.05-3.95]; adjusted P = 0.035). The frequencies of the four haplotypes (TA, CG, CA, TG) were not significantly different in the T2DM patients compared with control group (P > 0.025). Among diabetic group, an inverse trend with risk of cardio vascular diseases was shown in carriers of CG haplotype compared to those with TA haplotype (OR = 0.28, CI [0.09-0.90]; adjusted P = 0.035). Further, stratified analyses based on ESR1 PvuII and XbaI genotypes revealed no evidence for association with lipid levels (TC, TG, HDL, LDL).

Conclusions

This is the first Palestinian study to conclude that ESR1 PuvII and XbaI variants may contribute to diabetes susceptibility in Palestinian women. Identification of genetic risk markers can be used in defining high risk subjects and in prevention trials.

Maternal lipopolysaccharide exposure results in glucose metabolism disorders and sex hormone imbalance in male offspring

An adverse intrauterine environment may be an important factor contributing to the development of type 2 diabetes in later life. The present study investigated the longitudinal effects of maternal lipopolysaccharide (LPS) exposure during the third trimester on glucose metabolism and sex hormone balance in the offspring. Pregnant mice were intraperitoneally injected with LPS (50 μg/kg) daily from gestational day (GD) 15 to GD17. Glucose tolerance test (GTT) and insulin tolerance test (ITT) were assessed at postnatal day (PND) 60 and PND120. Sex hormones, their receptors, and metabolic enzymes (aromatase) were measured in male offspring at different phases of development (PND14: juvenile; PND35: adolescence; PND60: adulthood; and PND120: middle age). LPS-exposed male offspring exhibited glucose intolerance and insulin resistance by GTT and ITT at middle age, accompanied by an increase in fasting blood glucose and reductions in serum insulin levels and hepatic phosphorylated (p) -AKT/AKT ratio. However, glucose intolerance and insulin resistance were not observed in LPS-exposed female offspring. Maternal LPS exposure upregulated hepatic aromatase proteins and mRNA levels in male offspring at all time points. At adolescence, the testosterone/estradiol ratio (T/E2) was markedly reduced in LPS-exposed male offspring. Moreover, maternal LPS exposure significantly increased hepatic estrogen receptor (ER) α expressions and decreased hepatic androgen receptor (AR) expressions in male offspring. At adulthood, maternal LPS exposure increased serum estradiol levels, decreased serum testosterone levels and elevated hepatic ERβ expressions in male offspring. In conclusion, maternal LPS exposure upregulated aromatase expressions, followed by a reduction in the T/E2 ratio and an alteration in sex hormone receptor activity, which might be involved in the development of glucose metabolism disorders in middle-aged male offspring. This study provides a novel clue and direction to clarify the pathogenesis of maternal infection-related diabetes in male offspring.