Single Nucleotide Polymorphism rs17173608 in the Chemerin Encoding Gene: Is It a Predictor of Insulin Resistance and Severity of Coronary Artery Disease in Non-Obese Type 2 Diabetes?

Single nucleotide polymorphisms: Implications in the early diagnosis and targeted intervention of coronary microvascular dysfunction

Coronary microvascular dysfunction (CMD) is a clinical syndrome of myocardial ischemia caused by structural and/or functional abnormalities of pre-coronary arterioles and arterioles. While genetics and other factors play a role in CMD etiology, the key pathogenic mechanism remains unclear. Currently, the diagnostic procedure for CMD is still cumbersome, and there is a lack of effective targeted interventions. Single nucleotide polymorphisms (SNPs) offer promise in addressing these issues. SNPs, reflecting common genetic variations, have garnered extensive investigation across multiple diseases. Several SNPs associated with CMD have been discovered, and some have the potential to be therapeutic targets. Nevertheless, studies on CMD-related SNPs are relatively nascent and limited in number. In this review, we summarize the previously reported CMD-associated SNPs, delineate their pathophysiological mechanisms, and predict potentially important CMD sites by analyzing the SNPs linked to diseases sharing similar pathogenetic mechanisms and risk factors, such as coronary artery disease. We aim to explore reliable genetic markers implicated in CMD risk and prognosis, thereby providing a novel approach for early diagnosis and gene-targeted interventions of CMD in subsequent studies.

Adiponectin rs1501299 and chemerin rs17173608 gene polymorphism in children with type 1 diabetes mellitus: relation with macroangiopathy and peripheral artery disease

AIM

Although macrovascular complications represent the leading cause of mortality in type 1 diabetes mellitus (T1DM), the prevalence of subtle macrovascular affection including peripheral artery disease (PAD) among children with T1DM and its genetic predictors remains to be unraveled. Increasing evidence suggests a link between adiponectin rs1501299 and chemerin rs17173608 gene polymorphism and atherogenesis, and insulin resistance. Hence, this study assess the prevalence of these variants among children with T1DM in comparison to healthy controls and their association with macrovascular complications, namely PAD and hyperlipidemia.

METHODS

Fifty children with T1DM and 50 matched controls underwent a thorough assessment including adiponectin rs1501299 and chemerin rs17173608 gene polymorphisms, fasting lipids, glycated hemoglobin (HbA1c), and ankle-brachial index (ABI). Cochran-Armitage trend test was used to decide the risk allele and evaluate the association between the candidate variant and PAD using a case-control design.

RESULTS

Children with T1DM were found to have significantly higher ABI (p = 0.011) than controls. Chemerin gene polymorphism was detected in 41 children with T1DM (82.0%), while adiponectin gene polymorphism was detected in 19 children (38.0%). Children with T1DM having GG chemerin variant and those having TT adiponectin variant had significantly higher cholesterol with significantly lower HDL-C and ABI than those having the other two variants (p < 0.005). Children with T1DM having abnormal ABI had significantly higher chemerin G (p = 0.017) and adiponectin T (p = 0.022) alleles than those with normal ABI. Cholesterol and ABI were independently associated with chemerin and adiponectin gene polymorphism by multivariable regression analysis.

CONCLUSION

Children with T1DM having chemerin and adiponectin gene polymorphisms have significantly higher cholesterol and ABI than those without these polymorphisms and controls.

TRIAL REGISTRATION

The Research Ethics Committee of Ain Shams University, approval number R 31/2021.

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.

Microalgae as a Nutraceutical Tool to Antagonize the Impairment of Redox Status Induced by SNPs: Implications on Insulin Resistance

Microalgae represent a growing innovative source of nutraceuticals such as carotenoids and phenolic compound which are naturally present within these single-celled organisms or can be induced in response to specific growth conditions. The presence of the unfavourable allelic variant in genes involved in the control of oxidative stress, due to one or more SNPs in gene encoding protein involved in the regulation of redox balance, can lead to pathological conditions such as insulin resistance, which, in turn, is directly involved in the pathogenesis of type 2 diabetes mellitus. In this review we provide an overview of the main SNPs in antioxidant genes involved in the promotion of insulin resistance with a focus on the potential role of microalgae-derived antioxidant molecules as novel nutritional tools to mitigate oxidative stress and improve insulin sensitivity.

Genetic Markers of Insulin Resistance and Atherosclerosis in Type 2 Diabetes Mellitus Patients with Coronary Artery Disease

Type 2 diabetes mellitus (T2DM) is characterized by impaired insulin secretion on a background of insulin resistance (IR). IR and T2DM are associated with atherosclerotic coronary artery disease (CAD). The mechanisms of IR and atherosclerosis are known to share similar genetic and environmental roots. Endothelial dysfunction (ED) detected at the earliest stages of IR might be the origin of atherosclerosis progression. ED influences the secretion of pro-inflammatory cytokines and their encoding genes. The genes and their single nucleotide polymorphisms (SNPs) act as potential genetic markers of IR and atherosclerosis. This review focuses on the link between IR, T2DM, atherosclerosis, CAD, and the potential genetic markers CHI3L1, CD36, LEPR, RETN, IL-18, RBP-4, and RARRES2 genes.

Current Knowledge on the Pathophysiology of Lean/Normal-Weight Type 2 Diabetes

Since early times, being overweight and obesity have been associated with impaired glucose metabolism and type 2 diabetes (T2D). Similarly, a less frequent adult-onset diabetes in low body mass index (BMI) people has been known for many decades. This form is mainly found in developing countries, whereby the largest increase in diabetes incidence is expected in coming years. The number of non-obese patients with T2D is also on the rise among non-white ethnic minorities living in high-income Western countries due to growing migratory flows. A great deal of energy has been spent on understanding the mechanisms that bind obesity to T2D. Conversely, the pathophysiologic features and factors driving the risk of T2D development in non-obese people are still much debated. To reduce the global burden of diabetes, we need to understand why not all obese people develop T2D and not all those with T2D are obese. Moreover, through both an effective prevention and the implementation of an individualized clinical management in all people with diabetes, it is hoped that this will help to reduce this global burden. The purpose of this review is to take stock of current knowledge about the pathophysiology of diabetes not associated to obesity and to highlight which aspects are worthy of future studies.

Association of admission serum calcium level with left ventricular dysfunction in patients with acute coronary syndrome

Background

The relationship between serum calcium and left ventricular function in patients with acute coronary syndrome (ACS) has not been explored. Our aim was to investigate the correlation of admission serum calcium with left ventricular dysfunction in ACS patients.

Methods

In this cross-sectional study, 658 ACS patients who were admitted in the Department of Cardiovascular Disease from June 1st, 2019 to December 31st, 2019 were enrolled in the present study. Serum calcium and B-type natriuretic peptide (BNP) were measured at admission. Left ventricular ejection fraction (LVEF) was assessed using echocardiography. The correlation between admission serum calcium and left ventricular dysfunction was analyzed.

Results

When stratified by serum calcium quartiles calculated from all patients, patients with lower serum calcium quartile showed a markedly higher BNP and lower LVEF (P &lt; 0.05). Patients with LVEF ≤ 50% showed a significantly lower serum calcium and higher BNP compared to those with LVEF&gt; 50% (P &lt; 0.05). Admission serum calcium was positively correlated with LVEF (P &lt; 0.01) but negatively correlated with BNP (P &lt; 0.01). Multivariate logistic regression analysis showed that lower serum calcium (adjusted OR: 0.720, 95% CI: 0.519–0.997, P = 0.048) was independently associated with BNP ≥ 300 pg/ml in ACS patients. Using LVEF as a dependent variable, no significant correlation between low serum calcium and left ventricular systolic dysfunction was found in ACS patients.

Conclusions

In patients with ACS, admission serum calcium was positively correlated with LVEF and negatively with BNP. Lower admission serum calcium was an independent risk factor for elevated BNP.

Prognostic value of plasma adipokine chemerin in patients with coronary artery disease

Background

Adipokine chemerin was proven to be associated with coronary artery disease (CAD), but its prognostic implications in CAD remain unclear.

Methods

This study consists of two parts, one is a basic study and the other is a clinical cohort study. First, we investigated the differential expression of six adipokines in the atherosclerotic mice model compared to mice with milder degrees of atherosclerosis and mice without atherosclerosis using microarray data. We then examined the potential of chemerin as a diagnostic and prognostic indicator in a CAD cohort. A total of 152 patients were enrolled in our study, including 77 patients with angiographically proven CAD and 75 control subjects without cardiovascular disease. Plasma adipokine chemerin levels were measured in all patients, and major adverse cardiovascular events (MACEs) were followed up, including ischemic stroke, non-fatal myocardial infarction, revascularization, and cardiovascular death.

Results

In the aortas of atherosclerotic mice, chemerin expression was up-regulated compared to control mice. The plasma chemerin levels of CAD patients were higher than those of non-CAD patients (128.93 ± 37.06 vs. 109.85 ± 27.47 mmol/L, respectively, P < 0.001). High chemerin levels were an independent predictor of CAD (β = 2.702, 95% CI, 1.344–5.431, P = 0.001). We followed up with patients for a median duration of 5.5 years (3.9–5.6). The Kaplan–Meier curves showed that patients in the high chemerin group had a significantly higher risk of MACEs than the low chemerin group in patients with CAD (log-rank P = 0.003), not with non-CAD (Log-rank P = 0.120). Furthermore, Cox multivariate analysis revealed that high chemerin levels were an independent predictor of MACEs (HR 2.267; 95% CI, 1.139–4.515; P = 0.020). Finally, the cellular study showed that chemerin is predominantly expressed in PBMC-derived macrophages.

Conclusion

Plasma chemerin levels were increased in the CAD patients, and a high chemerin level increased the risk of MACEs in CAD patients.

Retinol-Binding Protein-4-A Predictor of Insulin Resistance and the Severity of Coronary Artery Disease in Type 2 Diabetes Patients with Coronary Artery Disease

(1) Background: Insulin resistance (IR) is the fundamental cause of type 2 diabetes (T2D), which leads to endothelial dysfunction and alters systemic lipid metabolism. The changes in the endothelium and lipid metabolism result in atherosclerotic coronary artery disease (CAD). In insulin-resistant and atherosclerotic CAD states, serum cytokine retinol-binding protein-4 (RBP-4) levels are elevated. The adipocyte-specific deletion of glucose transporter 4 (GLUT4) results in higher RBP-4 expression and IR and atherosclerotic CAD progression. (2) Aim: This study aimed to investigate the association of RBP-4 and clinical factors with IR and the severity of CAD. (3) Methods: Patients were recruited from diabetes and cardiology clinics and divided into three subgroups, namely (i) T2D patients with CAD, (ii) T2D-only patients, and (iii) CAD-only patients. The severity of CAD was classified as either single-vessel disease (SVD), double-vessel disease (DVD), or triple-vessel disease (TVD). An enzyme-linked immunosorbent assay was conducted to assess the concentration of serum RBP-4. Univariate (preliminary analysis) and multivariate (secondary analysis) logistic regressions were applied to assess the associations of RBP-4 and clinical factors with IR and the severity of CAD. (4) Results: Serum RBP-4 levels were associated with IR and the severity of CAD in all the three groups (all p-values are less than 0.05). Specifically, serum RBP-4 levels were associated with IR (p = 0.030) and the severity of CAD (SVD vs. DVD, p = 0.044; SVD vs. TVD, p = 0.036) in T2D patients with CAD. The clinical factors fasting plasma glucose (FPG) and angiotensin-converting-enzyme inhibitor (ACEI) were also associated with both IR and the severity of CAD in T2D patients with CAD. (5) Conclusion: RBP-4, FPG, and ACEI are predictors of IR and severity of CAD in T2D patients with CAD.