Association between chemerin rs17173608 and rs4721 gene polymorphisms and gestational diabetes mellitus in Iranian pregnant women

Association of RARRES2 rs17173608 gene polymorphism and serum Chemerin with acute myocardial infarction and its risk factors: A case-control study in an Iranian population

OBJECTIVE

The adipokine Chemerin and the retinoic acid receptor responder 2 (RARRES2) gene have been associated with an increased incidence of obesity, insulin resistance, endothelial dysfunction, type 2 diabetes mellitus, and coronary artery disease. The impact of RARRES2 rs17173608 gene polymorphism on acute myocardial infarction and Chemerin levels has not yet been entirely elucidated. This study aimed to assess the association of RARRES2 rs17173608 gene polymorphism and serum Chemerin with acute myocardial infarction (AMI) and its risk factors in an Iranian population.

METHODS

In this case-control study, 134 AMI patients and 100 healthy controls were recruited from tertiary referral hospitals in Zanjan, Iran. Whole blood samples were collected for DNA extraction and Chemerin level determination. An enzyme-linked immunosorbent assay was used to quantify plasma levels of Chemerin. Tetra-primer amplification refractory mutation system-polymerase chain reaction and agarose gel electrophoresis techniques were used to detect gene polymorphism of Chemerin rs17173608 from DNA samples.

RESULTS

Serum Chemerin levels were higher in the control group than in the AMI group. However, after adjusting for age, sex, and other risk factors, there was no significant association between serum Chemerin level and AMI occurrence. In the genotype analysis, 21.6% of patients had the TT genotype, and 78.4% had the TG genotype. The GG genotype was not detected in any patient. The genotype distribution of the healthy control group was 19.0% TT genotype, 80.0% TG genotype, and 1.0% GG genotype. Serum Chemerin levels in participants with TG genotype were statistically different between case and control groups.

CONCLUSION

Serum Chemerin levels and RARRES2 rs17173608 gene polymorphism were not correlated with AMI occurrence after adjusting for AMI risk factors in Iranian patients. More research with a larger sample size and diverse ethnicities is needed to corroborate our findings.

Gestational diabetes mellitus: genetic factors, epigenetic alterations, and microbial composition

Gestational diabetes mellitus (GDM) is a common metabolic disorder, usually diagnosed during the third trimester of pregnancy that usually disappears after delivery. In GDM, the excess of glucose, fatty acids, and amino acids results in foetuses large for gestational age. Hyperglycaemia and insulin resistance accelerate the metabolism, raising the oxygen demand, and creating chronic hypoxia and inflammation. Women who experienced GDM and their offspring are at risk of developing type-2 diabetes, obesity, and other metabolic or cardiovascular conditions later in life. Genetic factors may predispose the development of GDM; however, they do not account for all GDM cases; lifestyle and diet also play important roles in GDM development by modulating epigenetic signatures and the body's microbial composition; therefore, this is a condition with a complex, multifactorial aetiology. In this context, we revised published reports describing GDM-associated single-nucleotide polymorphisms (SNPs), DNA methylation and microRNA expression in different tissues (such as placenta, umbilical cord, adipose tissue, and peripheral blood), and microbial composition in the gut, oral cavity, and vagina from pregnant women with GDM, as well as the bacterial composition of the offspring. Altogether, these reports indicate that a number of SNPs are associated to GDM phenotypes and may predispose the development of the disease. However, extrinsic factors (lifestyle, nutrition) modulate, through epigenetic mechanisms, the risk of developing the disease, and some association exists between the microbial composition with GDM in an organ-specific manner. Genes, epigenetic signatures, and microbiota could be transferred to the offspring, increasing the possibility of developing chronic degenerative conditions through postnatal life.

Is Chemerin Associated with Gestational Diabetes Mellitus? A Case-Control Study

Purpose

The aim of this study was to investigate the relationship between gestational diabetes mellitus (GDM) and Chemerin by analyzing chemerin levels in peripheral blood and cord blood, and chemerin mRNA and its protein expression in placenta and adipose tissue.

Methods

A case-control study was conducted in 110 women with GDM and 110 controls without GDM who received regular prenatal services and delivered at Shanghai Pudong New Area Healthcare Hospital for Women and Children from June 2019 to December 2020.

Results

The age, pre-pregnancy weight, pre-pregnancy BMI, antepartum BMI, TG/HDL ratio and TG levels in pregnant women with GDM were significantly higher than those in women without GDM, and HDL levels were significantly lower than those in the normal group. Chemerin in the umbilical cord blood of the GDM group was significantly higher than in that of the normal group, but there was no difference in chemerin levels in peripheral blood. In the two groups, the chemerin concentration in peripheral blood was significantly higher than that in umbilical cord blood (P<0.001). The Chemerin mRNA and protein expression levels in the placenta and adipose tissue of pregnant women in the GDM group were significantly higher than those in the normal group (P <0.001). In the GDM group, the expression of chemerin protein in adipose tissue was significantly higher than that in placental tissue. Regression analysis showed that the expression level of chemerin protein in placental tissue and adipose tissue was positively correlated with the risk of GDM.

Conclusion

Elevated chemerin is closely related to the risk of GDM, and the placenta may be an important secretion of chemotactic factor sources in addition to adipose tissue and participate in the development of GDM.

Chemerin Forms: Their Generation and Activity

Chemerin is the product of the RARRES2 gene which is secreted as a precursor of 143 amino acids. That precursor is inactive, but proteases from the coagulation and fibrinolytic cascades, as well as from inflammatory reactions, process the C-terminus of chemerin to first activate it and then subsequently inactivate it. Chemerin can signal via two G protein-coupled receptors, chem1 and chem2, as well as be bound to a third non-signaling receptor, CCRL2. Chemerin is produced by the liver and secreted into the circulation as a precursor, but it is also expressed in some tissues where it can be activated locally. This review discusses the specific tissue expression of the components of the chemerin system, and the role of different proteases in regulating the activation and inactivation of chemerin. Methods of identifying and determining the levels of different chemerin forms in both mass and activity assays are reviewed. The levels of chemerin in circulation are correlated with certain disease conditions, such as patients with obesity or diabetes, leading to the possibility of using chemerin as a biomarker.

Single-nucleotide polymorphisms as important risk factors of diabetes among Middle East population

Diabetes is a chronic metabolic disorder that leads to the dysfunction of various tissues and organs, including eyes, kidneys, and cardiovascular system. According to the World Health Organization, diabetes prevalence is 8.8% globally among whom about 90% of cases are type 2 diabetes. There are not any significant clinical manifestations in the primary stages of diabetes. Therefore, screening can be an efficient way to reduce the diabetic complications. Over the recent decades, the prevalence of diabetes has increased alarmingly among the Middle East population, which has imposed exorbitant costs on the health care system in this region. Given that the genetic changes are among the important risk factors associated with predisposing people to diabetes, we examined the role of single-nucleotide polymorphisms (SNPs) in the pathogenesis of diabetes among Middle East population. In the present review, we assessed the molecular pathology of diabetes in the Middle East population that paves the way for introducing an efficient SNP-based diagnostic panel for diabetes screening among the Middle East population. Since, the Middle East has a population of 370 million people; the current review can be a reliable model for the introduction of SNP-based diagnostic panels in other populations and countries around the world.

Role of chemerin in the control of glucose homeostasis

Chemerin is an adipokine produced by the white adipose tissue and other tissues, which plays various roles in the pathogenesis of inflammatory and metabolic diseases in multiple organs. The present review aims at gathering scientific evidence reported in the last ten years, concerning the relationship of chemerin with alterations of glycaemic control, such as insulin resistance, type 2 diabetes and gestational diabetes in humans. Although the vast majority of the studies have shown a positive correlation between the chemerin level and a bad glycaemic control, a general consensus has not been reached. The reported results come from case-control and observational longitudinal studies, thereby limiting their interpretation. In fact, it cannot be stated whether insulin resistance and diabetes lead to an increase in chemerin levels or, on the contrary, if high levels of chemerin contribute to an impaired glycaemic control. Elevated levels of circulating chemerin are also associated with gestational diabetes mellitus. Chemerin gene polymorphisms could be proposed as mediators of glucose-related diseases. Nevertheless, to date very little is known about their implication in glucose metabolism. With regard to the mechanisms of action, chemerin impairs insulin cascade signaling by acting on several proteins of this cascade and by inducing inflammation.

Biochemical studies of adiponectin gene polymorphism in patients with obesity in Egyptians

BACKGROUND

Adiponectin gene polymorphisms have recently been reported to be associated with obesity. In Egypt, obesity has expanded especially with the changing nourishment propensities and the inexorably inactive ways of life, with almost 70 percent of the Egyptian populations being obese.

AIM

To assess the relationship of the adiponectin gene (ADIPOQ) polymorphism in patients with Obesity in Egyptians.

SUBJECTS AND METHODS

This study included 100 patients with obesity and 97 random controls.

RESULTS

Adiponectin rs1501299 polymorphism showed significant difference cases with different obesity grades where the T/T genotype was relatively higher in higher classes of obesity (Class II and III; (66.7% and 55.6% respectively, p = 000), which determines the susceptibility to obesity.

CONCLUSION

Adiponectin rs1501299 polymorphism might be a candidate gene, which determines the susceptibility to obesity. Larger studies are necessary to confirm these findings in various populations.

Chemerin levels and its genetic variants are associated with Gestational Diabetes Mellitus: a hospital-based study in a Chinese cohort

BACKGROUND

Gestational diabetes mellitus (GDM) is a glucose intolerance condition encounters for the first time in a fraction of pregnant women. The role of different host inflammatory molecules in GDM etiology has been deciphered. Chemerin is a chemoattractant protein primarily associated with the pathogenesis of type 2 diabetes, obesity, and metabolic syndrome. However, the association of chemerin and its genetic variants with the predisposition of GDM is not clear, and our present study is aimed to address the issue.

MATERIALS AND METHODS

A total of 703 Chinese women comprising of GDM (n=303), glucose tolerant pregnant women (n=211), and non-pregnant glucose tolerant controls (n=189) were recruited in the present investigation. GDM was diagnosed according to the World Health Organization recommendation for diagnosis of gestational diabetes during pregnancy. Plasma levels of chemerin were quantified by an Enzyme-linked Immunosorbent Assay (ELISA). Common variants in the chemerin gene (rs4721, rs17173617, rs7806429, and rs17173608) were genotyped by using TaqMan assay.

RESULTS

Plasma chemerin level was found higher in subjects with GDM as compared to glucose tolerant pregnant and non-pregnant women. Further, a positive correlation between plasma chemerin and HOMA-IR index suggesting an essential role of chemerin in mediating insulin resistance. Variants of rs4721 and rs17173608 polymorphisms were associated with lower levels of plasma chemerin and low HOMA-IR index. Furthermore, mutants of rs4721 and rs17173608 polymorphisms were associated with protection against the development of GDM in the Chinese cohort.

CONCLUSIONS

Plasma chemerin is elevated in GDM patients. Genetic variation in chemerin gene associated with lower plasma levels of chemerin, HOMA-IR index and protects against the development of GDM in Chinese.

The Role of the Adipokines in the Most Common Gestational Complications

Adipocytokines are hormonally active molecules that are believed to play a key role in the regulation of crucial biological processes in the human body. Numerous experimental studies established significant alterations in the adipokine secretion patterns throughout pregnancy. The exact etiology of various gestational complications, such as gestational diabetes, preeclampsia, and fetal growth abnormalities, needs to be fully elucidated. The discovery of adipokines raised questions about their potential contribution to the molecular pathophysiology of those diseases. Multiple studies analyzed their local mRNA expression and circulating protein levels. However, most studies report conflicting results. Several adipokines such as leptin, resistin, irisin, apelin, chemerin, and omentin were proposed as potential novel early markers of heterogeneous gestational complications. The inclusion of the adipokines in the standard predictive multifactorial models could improve their prognostic values. Nonetheless, their independent diagnostic value is mostly insufficient to be implemented into standard clinical practice. Routine assessments of adipokine levels during pregnancy are not recommended in the management of both normal and complicated pregnancies. Based on the animal models (e.g., apelin and its receptors in the rodent preeclampsia models), future implementation of adipokines and their receptors as new therapeutic targets appears promising but requires further validation in humans.

The associations among RARRES2 rs17173608 gene polymorphism, serum chemerin, and non-traditional lipid profile in patients with metabolic syndrome

Background

The adipokine chemerin retinoic acid receptor responder protein 2 (RARRES2) has been associated with insulin resistance, type II diabetes mellitus (T2DM), obesity, and metabolic syndrome (MetS). The impact of RARRES2 rs17173608 gene polymorphism on MetS and chemerin levels is not completely elucidated. This study included 100 patients with MetS and 68 healthy subjects (non-MetS group). The RARRES2 rs17173608 gene variant was analyzed by tetra amplification refractory mutation system polymerase chain reaction (T-ARMS-PCR). Circulating chemerin levels were determined by ELISA. Serum urea, creatinine, fasting blood glucose, glycated hemoglobin, and traditional lipid profile were measured by colorimetric methods. The estimated glomerular filtration rate (eGFR) and non-traditional lipid parameters were calculated.

Results

Serum chemerin levels were significantly higher in MetS than in non-MetS subjects, type II diabetics (T2DM) than non-diabetics, and overweight compared to lean subjects, but it did not differ significantly between patients with and without hypertension. Strikingly, newly diagnosed diabetic patients had significantly higher serum chermerin levels. Correlation and multiple linear regression analysis showed that serum chemerin levels and non-traditional lipid parameters were correlated significantly with the clinical criteria of MetS. Genotyping and allelic frequency distribution of RARRES2 rs17173608 gene polymorphism showed its significant association with MetS. The TT genotype of RARRES2 rs17173608 SNP was more distributed in T2DM in comparison with non-diabetics, and it was associated significantly with higher serum chemerin and higher glycated hemoglobin levels. RARRES2 rs17173608 GG genotype and G allele frequency were less distributed in T2DM patients than in non-diabetic patients.

Conclusions

The RARRES2 rs17173608 SNP might have an impact on chemerin levels and lipid parameters. The GG genotype and G allele may have a protective role towards the risk of T2DM but not for MetS. Serum chemerin and non-traditional lipid profile are significantly associated with MetS.

The impact of GSTM1 and GSTT1 polymorphisms on susceptibility to gestational diabetes in Iranian population

Background: Gestational diabetes mellitus (GDM) is characterized as a common metabolic disorder during pregnancy which is associated with glucose intolerance and insulin resistance. Genetic predisposition could contribute to the development of GDM.Methods: We conducted a case-control study to inspect the impact of GSTM1 and GSTT1 polymorphism on GDM susceptibility in Iranian population. The population consisted of 149 pregnant women with GDM as cases, and 138 healthy pregnant women without any history of GDM as controls. Polymerase chain reaction-restriction fragment length polymorphism method was applied to determine the GSTM1 and GSTT1 gene polymorphisms.Results: There were statistically significant differences between the cases and controls in terms of age (p = .005), BMI (p < .001), family history of gestational diabetes (p < .001), FBS (p = .001), TG (p ≤ .001), and HDL (p = .003). However, no significant differences were observed in TC (p = .078) and LDL (p = .062). There were significant differences between GSTM1 polymorphism (Null and present) in the case and controls groups [OR (95% CI); 2.3 (1.4-3.7), p < .001]. The distribution of GSTM1-null genotype was found to be significantly higher in GDM patients (68.6%) than the control group (48.5%). No significant variance was detected between GSTT1 polymorphism (Null and present) in the case and controls groups [OR (95% CI); 1.1 (0.6-1.6), p = .088]. The frequency of GSTM1 null/GSTT1 null [OR (95% CI); 2.7 (1.2-5.2), p = .01] and GSTM1 null/GSTT1 present [OR (95% CI); 2.6 (1.4-4.8), p = .002] genotypes significantly differed between the GDM and control groups.Conclusion: It seems that GSTM1 null genotype might be considered as GDM risk factor in Iranian population.

Update on the genetic and epigenetic etiology of gestational diabetes mellitus: a review

Background

Many studies have been conducted on the genetic and epigenetic etiology of gestational diabetes mellitus (GDM) in the last two decades because of the disease’s increasing prevalence and role in global diabetes mellitus (DM) explosion. An update on the genetic and epigenetic etiology of GDM then becomes imperative to better understand and stem the rising incidence of the disease. This review, therefore, articulated GDM candidate genes and their pathophysiology for the awareness of stakeholders.

Main body (genetic and epigenetic etiology, GDM)

The search discovered 83 GDM candidate genes, of which TCF7L2, MTNR1B, CDKAL1, IRS1, and KCNQ1 are the most prevalent. Certain polymorphisms of these genes can modulate beta-cell dysfunction, adiposity, obesity, and insulin resistance through several mechanisms. Environmental triggers such as diets, pollutants, and microbes may also cause epigenetic changes in these genes, resulting in a loss of insulin-boosting and glucose metabolism functions. Early detection and adequate management may resolve the condition after delivery; otherwise, it will progress to maternal type 2 diabetes mellitus (T2DM) and fetal configuration to future obesity and DM. This shows that GDM is a strong risk factor for T2DM and, in rare cases, type 1 diabetes mellitus (T1DM) and maturity-onset diabetes of the young (MODY). This further shows that GDM significantly contributes to the rising incidence and burden of DM worldwide and its prevention may reverse the trend.

Conclusion

Mutations and epigenetic changes in certain genes are strong risk factors for GDM. For affected individuals with such etiologies, medical practitioners should formulate drugs and treatment procedures that target these genes and their pathophysiology.

Serum concentration of angiogenic (CXCL1, CXCL12) and angiostasis (CXCL9, CXCL10) CXC chemokines are differentially altered in normal and gestational diabetes mellitus associated pregnancies

BACKGROUND

The present study was aimed and designed to determine the serum levels of CXCL1 and CXCL12 as angiogenesis along with CXCL9 and CXCL10 as angiostasis, chemokines in, Gestational diabetes mellitus mothers (GDMM) and normal pregnancy mothers (NPM) and neonates who delivered by them.

METHODS

We have recruited 63 pregnant GDMM and 63 normal pregnant mothers at the third trimester of pregnancy to this cross-sectional study. Cord blood specimens were obtained from neonates who were delivered from GDMM and NPM. The serum and cord blood levels of chemokines were measured by ELISA in studied groups. Data were analyzed by chi-square and student's t test between two groups. The P-values less than 0.05 were considered significant.

RESULTS

Our results revealed that the serum levels of CXCL1, CXCL9 and CXCL12 were increased in GDMM, while no alteration was found in the serum levels of CXCL10 when compared to NPM. We have observed that in neonates the serum levels of angiogeneic chemokines followed an inverse fashion when compared to angiostasis chemokines. Interestingly, CXCL1 and CXCL12 were both increased in neonates who were delivered by GDMM, while, CXCL9 and CXCL10 were decreased in neonates delivered by GDMM.