Association of estrogen receptor alpha gene polymorphisms with metabolic syndrome in Egyptian women

The evolutionary impact and influence of oestrogens on adipose tissue structure and function

Oestrogens are sex steroid hormones that have gained prominence over the years owing to their crucial roles in human health and reproduction functions which have been preserved throughout evolution. One of oestrogens actions, and the focus of this review, is their ability to determine adipose tissue distribution, function and adipose tissue 'health'. Body fat distribution is sexually dimorphic, affecting males and females differently. These differences are also apparent in the development of the metabolic syndrome and other chronic conditions where oestrogens are critical. In this review, we summarize the different molecular mechanisms, pathways and resulting pathophysiology which are a result of oestrogens actions in and on adipose tissues. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part I)'.

Metabolic Syndrome, BMI, and Polymorphism of Estrogen Receptor-α in Peri- and Post-Menopausal Polish Women

The study aimed to investigate the association between the estrogen receptor alpha (ERα) polymorphism and the prevalence of metabolic syndrome (MetS) and obesity, as well as the coexistence of MetS and obesity, in peri- and post-menopausal Polish women. The study group consisted of 202 peri-menopausal and 202 post-menopausal women. ERα polymorphism: Xba I and Pvu II, MetS, BMI, and serum estrogen concentration were analyzed. MetS was found in 29% of the peri-menopausal women and in 21% of the post-menopausal women. BMI did not significantly differ between the peri- and post-menopausal women (≈42% were normal weight, ≈40% were overweight, and ≈18% were obese), (p = 0.82). Serum estrogen concentration in the peri-menopausal women was 91 ± 75 pg/mL, while that in the post-menopausal women was 17 ± 9. pg/mL, on average. Peri-menopausal women with AA and TT genotypes of the ERα polymorphism have a lower risk of obesity and MetS and the co-existence of obesity and MetS, whereas those women with the G or C allele have a higher risk of those health problems.

Associations of serum vitamin D and Fok I polymorphism of receptor gene with unexplained recurrent spontaneous abortion

Background: To investigate the associations of serum vitamin D and Fok I polymorphism of its receptor (VDR) with unexplained recurrent spontaneous abortion (URSA).

Methods: Ninety URSA patients and another 104 healthy pregnant women were selected as URSA and control groups, respectively. 25-Hydroxyvitamin D [25-(OH)D] level was detected by chemiluminescence. VDR gene Fok I polymorphism was analyzed by PCR, and the distribution of genotype frequency was calculated by Hardy-Weinberg equilibrium test. Association between Fok I polymorphism and susceptibility to URSA was investigated by logistic regression analysis.

Results: Gestational age, uterine height, waist circumference, 25-(OH)D level and proportions of Fok I FF and Ff genotypes were significantly lower in the URSA group (P<0.05). Compared with ff genotype, risk of URSA reduced for Ff and FF genotypes. Compared with allele f, risk of URSA was lower for allele F. 25-(OH)D level of ff genotype was significantly lower in the URSA group, which was lower than that of FF genotype (P<0.05). Compared with women with 25-(OH)D level >30 ng/mL and F allele (FF+Ff), the risk of URSA increased 2.45-, 2.43- and 5.34-fold for those with 25-(OH)D level >30 ng/mL and ff genotype, with 25-(OH)D level ≤30 ng/mL, and with ff genotype and 25-(OH)D level ≤30 ng/mL, respectively.

Conclusions: The 25-(OH)D level of the URSA group was significantly lower than that of normal pregnant women. Probably, VDR gene Fok I polymorphism is associated with URSA occurrence, and allele F decreases the risk. The risk of URSA dramatically increases in women with ff genotype and 25-(OH)D deficiency.

Genetic Studies of Metabolic Syndrome in Arab Populations: A Systematic Review and Meta-Analysis

Background: The metabolic syndrome (MetS) is prevalent in Arabian populations. Several small-scale studies have been performed to investigate the genetic basis of MetS. This systematic review and meta-analysis aimed to examine whether candidate gene polymorphisms are associated with MetS susceptibility among ethnic groups of the Arabian world and to suggest possible directions for future research regarding genetic markers and MetS.

Methods: A search was conducted for peer-reviewed articles that examined the genetic association of MetS in Arabian populations in the following databases: Medline, Embase, Scopus, Direct Science, Web of Science, ProQuest, and Google Scholar until March 31, 2021. Articles were eligible if they were case-control studies, which investigated MetS as a dichotomous outcome (MetS vs no MetS). To assess the quality of the studies, the Q-Genie tool (Quality of Genetic Association Studies) was used. A non-central chi2 (random-effect) distribution was used to determine the heterogeneity (H) of Q and I (Galassi et al., The American journal of medicine, 2006, 119, 812–819) statistics.

Results: Our search strategy identified 36 studies that met our inclusion criteria. In most cases, studies were excluded due to a lack of statistical information such as odds ratios, confidence intervals, and p-values. According to the Q-Genie tool, 12 studies scored poorly (a score of≤35), 13 studies scored moderately ( >35 and≤45), and 12 studies had good quality ( >45 or higher). The most frequently studied genes were FTO and VDR (both included in four studies). Three SNPs indicated increased risk for MetS after calculating the pooled odds ratios: FTO-rs9939609 (odds ratio 1.49, 95% CI: 0.96–2.32); LEP-rs7799039 (odds ratio 1.85, 95% CI: 1.37–2.5); and SERPINA12-rs2236242 (odds ratio 1.65, 95% CI: 1.21–2.24). Meta-analysis studies showed no significant heterogeneity.

Conclusion: There were many sources of heterogeneity in the study settings. Most of the studies had low to moderate quality because of sample size and power issues, not considering all potential sources of bias, and not providing details about genotyping methods and results. As most studies were small-scale, aimed to replicate findings from other populations, we did not find any unique genetic association between MetS and Arabian populations.

Prevalence of ApoB100 rs693 gene polymorphism in metabolic syndrome among female students at King Abdulaziz University

Apolipoprotein B100 (ApoB100) is a glycoprotein and a member of the adipokine family. It plays a central role in lipoprotein metabolism. Many research studies have revealed a strong relation between ApoB100 and metabolic syndrome (MetS) and insulin resistance.

In our research, we examined the relationship between ApoB100 rs693 gene polymorphism, body mass index (BMI) and the probability of MetS in young female students studying at King Abdulaziz University (KAU) in Saudi Arabia. The study group comprised 141 females whose ages ranged from 18 to 25 years. Anthropometric measurements and biochemical parameters were measured alongside a genetic analysis of ApoB100 rs693.

The BMI, glucose concentration and total cholesterol level were found to be significantly associated with the ApoB100 rs693 gene. The differences noted between control and MetS groups regarding glucose concentrations were statistically significant (P = 0.001).

A growing number of young females are being diagnosed with MetS in KAU because of unhealthy eating habits, in combination with the absence of physical exercise, causing increased body weight and the potential progression of chronic diseases. Our study showed that the allele associated with hypertensive individuals at ApoB100 rs693 and MetS may have a direct genetic influence. Further research on expanded sample sizes, however, is required in order to draw rigid conclusions.

Estrogen receptor 1 gene polymorphisms are associated with metabolic syndrome in postmenopausal women in China

BACKGROUND

Metabolic syndrome (MetS) includes obesity, diabetes, dyslipidemia and hypertension. Its incidence is rapidly increasing worldwide, particularly in postmenopausal women. Estrogens regulate glucose homeostasis and lipid metabolism via estrogen receptors 1 (ESR1) and 2 (ESR2). The current study aimed to elucidate associations of MetS with ESR1 and ESR2 gene polymorphisms in postmenopausal Chinese women.

METHODS

This case-control study included 304 postmenopausal women (154 and 150 control and MetS patients, respectively). Clinical indicators related to MetS were assessed. Two ESR1 (PvuII and XbaI) and two ESR2 (RsaI and AluI) polymorphisms were evaluated by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis.

RESULTS

ESR1 polymorphisms were significantly different between MetS patients and healthy controls. G allele frequency for the XbaI polymorphism was significantly higher in patients than in control patients (p = 0.004, OR = 1.610, 95%CI 1.169-2.18). The haplotypes A-T (p = 0.015) and G-C (p = 0.024) showed significant differences. The minor alleles of the XbaI and PvuII gene polymorphisms in both homozygous and heterozygous forms showed associations with elevated waist circumference, fasting serum insulin and HOMA-IR. The minor G allele in homozygous and heterozygous forms of the RsaI and AluI gene polymorphisms showed associations with elevated total cholesterol and LDL-C.

CONCLUSIONS

In postmenopausal Chinese women, ESR1 polymorphism and the haplotypes A-T and G-C of XbaI-PvuII are associated with MetS, unlike ESR2 polymorphisms. Patients harboring the G allele of XbaI have elevated BMI, waist circumference, systolic and diastolic BP, FBG, HOMA-IR, total cholesterol, TG, LDL-C and NAFLD (%), and reduced HDL-C.

Sex Hormones and Cardiometabolic Health: Role of Estrogen and Estrogen Receptors

With increased life expectancy, women will spend over three decades of life postmenopause. The menopausal transition increases susceptibility to metabolic diseases such as obesity, diabetes, cardiovascular disease, and cancer. Thus, it is more important than ever to develop effective hormonal treatment strategies to protect aging women. Understanding the role of estrogens, and their biological actions mediated by estrogen receptors (ERs), in the regulation of cardiometabolic health is of paramount importance to discover novel targeted therapeutics. In this brief review, we provide a detailed overview of the literature, from basic science findings to human clinical trial evidence, supporting a protective role of estrogens and their receptors, specifically ERα, in maintenance of cardiometabolic health. In so doing, we provide a concise mechanistic discussion of some of the major tissue-specific roles of estrogens signaling through ERα. Taken together, evidence suggests that targeted, perhaps receptor-specific, hormonal therapies can and should be used to optimize the health of women as they transition through menopause, while reducing the undesired complications that have limited the efficacy and use of traditional hormone replacement interventions.

Association of chemerin Rs17173608 and vaspin Rs2236242 gene polymorphisms with metabolic syndrome in Egyptian women

AIM

The metabolic syndrome is a complex of interrelated risk factors for cardiovascular disease and diabetes. The adipokines, chemerin and vaspin, are known to have metabolic regulatory roles. This study aimed to assess the relation of chemerin rs17173608 and vaspin rs2236242 polymorphisms with metabolic syndrome and its related phenotypes in Egyptian women.

SUBJECTS AND METHODS

The study included 100 healthy female subjects and 100 metabolic syndrome patients. The component traits of metabolic syndrome were determined and the genotypes of the polymorphisms were assessed using the tetra amplification refractory mutation system polymerase chain reaction procedure.

RESULTS

The minor G allele of the chemerin rs17173608 polymorphism had a significantly higher frequency in metabolic syndrome patients (p = 0.0001). The component traits of metabolic syndrome were significantly increased in the carriers of the GG and TG genotypes. In contrast, the rare A allele of vaspin rs2236242 polymorphism was significantly higher in the control subjects (p = 0.005). The carriers of the TA and AA genotypes showed significant relation with lower values of the phenotypes of metabolic syndrome.

CONCLUSION

Metabolic syndrome in Egyptian females is associated with the minor allele of chemerin rs17173608 polymorphism, whereas the minor allele of vaspin rs2236242 polymorphism plays a protective role against metabolic syndrome.

Polymorphisms in the LPL and CETP Genes and Haplotype in the ESR1 Gene Are Associated with Metabolic Syndrome in Women from Southwestern Mexico

Metabolic syndrome (MetS) is a combination of metabolic disorders associated with an increased risk for cardiovascular disease (CVD). Studies in women reported associations between polymorphisms in ESR1, LPL and CETP genes and MetS. Our aim was to evaluate the association between variants in ESR1, LPL and CETP genes with MetS and its components. Four hundred and eighty women were analyzed, anthropometric features and biochemical profiles were evaluated, and genotyping was performed by real-time PCR. We found an association with elevated glucose levels (odds ratio (OR) = 2.9; p = 0.013) in carrying the AA genotype of rs1884051 in the ESR1 gene compared with the GG genotype, and the CC genotype of rs328 in the LPL gene was associated with MetS compared to the CG or GG genotype (OR = 2.8; p = 0.04). Moreover, the GA genotype of rs708272 in the CETP gene is associated with MetS compared to the GG or AA genotype (OR = 1.8; p = 0.006). In addition the ACTCCG haplotype in the ESR1 gene is associated with a decrease in the risk of MetS (OR = 0.02; p < 0.001). In conclusion, our results show the involvement of the variants of ESR1, LPL and CETP genes in metabolic events related to MetS or some of its features.

Genetic association studies of obesity in Africa: a systematic review

Obesity is increasing in Africa, but the underlying genetic background largely remains unknown. We assessed existing evidence on genetic determinants of obesity among populations within Africa. MEDLINE and EMBASE were searched and the bibliographies of retrieved articles were examined. Included studies had to report on the association of a genetic marker with obesity indices and the presence/occurrence of obesity/obesity trait. Data were extracted on study design and characteristics, genetic determinants and effect estimates of associations with obesity indices. According to this data, over 300 polymorphisms in 42 genes have been studied in various population groups within Africa mostly through the candidate gene approach. Polymorphisms in genes such as ACE, ADIPOQ, ADRB2, AGRP, AR, CAPN10, CD36, C7orf31, DRD4, FTO, MC3R, MC4R, SGIP1 and LEP were found to be associated with various measures of obesity. Of the 36 polymorphisms previously validated by genome-wide association studies (GWAS) elsewhere, only FTO and MC4R polymorphisms showed significant associations with obesity in black South Africans, Nigerians and Ghanaians. However, these data are insufficient to establish the true nature of genetic susceptibility to obesity in populations within Africa. There has been recent progress in describing the genetic architecture of obesity among populations within Africa. This effort needs to be sustained via GWAS studies.

Relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women

CONTEXT

Myeloperoxidase is a heme protein secreted by activated macrophages and generates intermediates that oxidize lipoproteins. Myeloperoxidase-463G/A is a functional polymorphism involved in regulation of myeloperoxidase expression.

OBJECTIVE

The aim of this study is to assess the relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women from the Suez Canal area.

METHODS

The study includes 100 healthy female subjects and 100 metabolic syndrome patients. The component traits of metabolic syndrome are determined and the genotypes of the polymorphisms assessed using the PCR-RFLP technique.

RESULTS

There was no significant difference in the allele frequencies between the metabolic syndrome and control groups. However, the GA and AA genotypes were associated with lower total cholesterol, LDL-C, systolic and diastolic blood pressure in the patients.

CONCLUSION

Myeloperoxidase-463G/A polymorphism is not associated with the incidence of metabolic syndrome.

An estrogen-responsive module in the ventromedial hypothalamus selectively drives sex-specific activity in females

Estrogen-receptor alpha (ERα) neurons in the ventrolateral region of the ventromedial hypothalamus (VMHVL) control an array of sex-specific responses to maximize reproductive success. In females, these VMHVL neurons are believed to coordinate metabolism and reproduction. However, it remains unknown whether specific neuronal populations control distinct components of this physiological repertoire. Here, we identify a subset of ERα VMHVL neurons that promotes hormone-dependent female locomotion. Activating Nkx2-1-expressing VMHVL neurons via pharmacogenetics elicits a female-specific burst of spontaneous movement, which requires ERα and Tac1 signaling. Disrupting the development of Nkx2-1(+) VMHVL neurons results in female-specific obesity, inactivity, and loss of VMHVL neurons coexpressing ERα and Tac1. Unexpectedly, two responses controlled by ERα(+) neurons, fertility and brown adipose tissue thermogenesis, are unaffected. We conclude that a dedicated subset of VMHVL neurons marked by ERα, NKX2-1, and Tac1 regulates estrogen-dependent fluctuations in physical activity and constitutes one of several neuroendocrine modules that drive sex-specific responses.