Association of MCP-1 -2518 A/G single nucleotide polymorphism with the serum level of CRP in Slovak patients with ischemic heart disease, angina pectoris, and hypertension

Association of eNOS and MCP-1 Genetic Variants with Type 2 Diabetes and Diabetic Nephropathy Susceptibility: A Case-Control and Meta-Analysis Study

Type 2 diabetes (T2D) and its secondary complications result from the complex interplay of genetic and environmental factors. To understand the role of these factors on disease susceptibility, the present study was conducted to assess the association of eNOS and MCP-1 variants with T2D and diabetic nephropathy (DN) in two ethnically and geographically different cohorts from North India. A total of 1313 subjects from two cohorts were genotyped for eNOS (rs2070744, rs869109213 and rs1799983) and MCP-1 (rs1024611 and rs3917887) variants. Cohort-I (Punjab) comprised 461 T2D cases (204 T2D with DN and 257 T2D without DN) and 315 healthy controls. Cohort-II (Jammu and Kashmir) included 337 T2D (150 T2D with DN and 187 T2D without DN) and 200 controls. Allele, genotype and haplotype frequencies were compared among the studied participants, and phenotype-genotype interactions were determined. Meta-analysis was performed to investigate the association between the selected variants and disease susceptibility. All three eNOS variants were associated with 1.5-4.0-fold risk of DN in both cohorts. MCP-1 rs1024611 conferred twofold risk towards DN progression in cohort-II, while rs3917887 provided twofold risk for both T2D and DN in both cohorts. eNOS and MCP-1 haplotypes conferred risk for T2D and DN susceptibility. Phenotype-genotype interactions showed significant associations between the studied variants and anthropometric and biochemical parameters. In meta-analysis, all eNOS variants conferred risk towards DN progression, whereas no significant association was observed for MCP-1 rs1024611. We show evidences for an association of eNOS and MCP-1 variants with T2D and DN susceptibility.

Does C-C Motif Chemokine Ligand 2 (CCL2) Link Obesity to a Pro-Inflammatory State?

The mechanisms of how obesity contributes to the development of cardio-metabolic diseases are not entirely understood. Obesity is frequently associated with adipose tissue dysfunction, characterized by, e.g., adipocyte hypertrophy, ectopic fat accumulation, immune cell infiltration, and the altered secretion of adipokines. Factors secreted from adipose tissue may induce and/or maintain a local and systemic low-grade activation of the innate immune system. Attraction of macrophages into adipose tissue and altered crosstalk between macrophages, adipocytes, and other cells of adipose tissue are symptoms of metabolic inflammation. Among several secreted factors attracting immune cells to adipose tissue, chemotactic C-C motif chemokine ligand 2 (CCL2) (also described as monocyte chemoattractant protein-1 (MCP-1)) has been shown to play a crucial role in adipose tissue macrophage infiltration. In this review, we aimed to summarize and discuss the current knowledge on CCL2 with a focus on its role in linking obesity to cardio-metabolic diseases.

Chemokines and Heart Disease: A Network Connecting Cardiovascular Biology to Immune and Autonomic Nervous Systems

Among the chemokines discovered to date, nineteen are presently considered to be relevant in heart disease and are involved in all stages of cardiovascular response to injury. Chemokines are interesting as biomarkers to predict risk of cardiovascular events in apparently healthy people and as possible therapeutic targets. Moreover, they could have a role as mediators of crosstalk between immune and cardiovascular system, since they seem to act as a “working-network” in deep linkage with the autonomic nervous system. In this paper we will describe the single chemokines more involved in heart diseases; then we will present a comprehensive perspective of them as a complex network connecting the cardiovascular system to both the immune and the autonomic nervous systems. Finally, some recent evidences indicating chemokines as a possible new tool to predict cardiovascular risk will be described.

Association of monocyte chemoattractant protein-1 (MCP-1)-2518A>G polymorphism with susceptibility to coronary artery disease: a meta-analysis

We attempted to systematically elucidate the association between monocyte chemoattractant protein-1 (MCP-1) -2518A>G polymorphism and risk of coronary artery disease (CAD). Eligible studies were identified through PubMed, EBSCO, and Web of Science Databases. The magnitude of MCP-1 polymorphism effect and its possible mode of action on CAD were estimated. The odds ratio (OR) with 95% confidence intervals (CI) were pooled in a specific genetic model to assess the association. A total of 21 studies were involved. There was significant gene effect on CAD risk in the overall population (likelihood ratio test: p < 0.0001). Patients with GG and AG genotypes had 1.435 (95% CI: 1.183-1.740) and 1.087 (95% CI: 1.008-1.172) times higher risk of CAD than those with AA genotype. These gene effects suggested a recessive model to be appropriate. The pooled OR was 1.362 (95% CI: 1.137-1.631; puncorrected = 0.001, pFDR = 0.005) in the recessive model. In the ethnicity-stratified analysis, significant association was observed in the Caucasian population (OR = 1.492; 95% CI: 1.106-2.014; puncorrected = 0.009, pFDR = 0.015), whereas no statistical significant association was detected in the Asian population (adjusted p = 0.124). The results suggested that MCP-1 -2518A>G polymorphism may be associated with susceptibility to CAD, especially in Caucasians.

The associations between the MCP-1 -2518 A/G polymorphism and ischemic heart disease and ischemic stroke: a meta-analysis of 28 research studies involving 21,524 individuals

Epidemiologic studies have been performed to explore the relationship between MCP-1 polymorphism and ischemic heart disease (IHD) and ischemic stroke (IS). But, the results are not consistent. Because of the poor effect of each individual study, we've performed a systematic review and a meta-analysis. A comprehensive search was carried out from PubMed, Embase, Foreign Medical Journal Service (FMJS), China National Knowledge Infrastructure and Wanfang Data. Odds ratios (OR) with 95% confidence interval (CI) were used to evaluate the strength of associations between the MCP-1 A-2518G polymorphism (rs1024611) and IHD and IS susceptibilities. The pooled OR was calculated by the allelic model (G vs A), the additive model (GG vs AA), the dominant model (GG+GA vs AA) and the recessive model (GG vs AA+GA), respectively. The homogeneity among studies was checked using Cochrane Q statistic. The stability of results was checked by one-way sensitivity analysis. The publication bias between studies was examined by Begg's funnel plots and Egger's test. 28 eligible case-control studies met all the criteria and were involved in the present meta-analysis, including a total of 8,901 cases and 12,623 controls. Overall, the MCP-1 A-2518G polymorphism was significantly associated with the IHD susceptibility. The pooled OR was 1.27 (95% CI 1.09-1.48, P = 0.002) in the dominant model, 1.20 (95% CI 1.07-1.35, P = 0.001) in the allelic model, 1.25 (95% CI 1.05-1.50, P = 0.015) in the recessive model and 1.39 (95% CI 1.10-1.75, P = 0.005) in the additive model. At the same time, the MCP-1 A-2518G polymorphism was significantly associated with the IS susceptibility. The pooled OR was 1.72 (95% CI 1.12-2.65, P = 0.013) in the dominant model, 1.39 (95% CI 1.12-1.74, P = 0.003) in the allelic model, 1.59 (95% CI 1.30-1.93, P = 0.000) in the recessive model, and 2.33 (95% CI 1.76-3.08, P = 0.000) in the additive model, respectively. No significant publication bias was found in the present meta-analysis. The results of the present meta-analysis suggest that MCP-1 gene A-2518G polymorphism may be associated with the IHD and IS susceptibilities. But the positive result exists in relatively small sample size subgroup.

Monocyte chemoattractant protein-1 (MCP-1) g.-2518A>G polymorphism and susceptibility to type 2 diabetes (T2D) and end stage renal disease (ESRD) in the North-West Indian population of Punjab

BACKGROUND

Diabetic nephropathy (DN) is a major microvascular complication that develops in nearly 20-30% of patients with type 2 diabetes (T2D) and is currently the leading cause of end stage renal disease (ESRD). Monocyte chemoattractant protein-1 (MCP-1), a potent chemokine secreted by adipocytes, has been implicated as a causal factor in the progression of vascular complications in T2D, thus MCP-1 appears to be a promising candidate for association study.

AIM

The objective of the present study is to evaluate the association, if any, of g.-2518A>G polymorphism (rs1024611) in MCP-1 gene in T2D cases with and without ESRD in the population of Punjab from North-West India.

SUBJECTS AND METHODS

A total of 571 samples from Punjab comprising 350 T2D cases (145 with ESRD and 205 without ESRD) and 221 controls were genotyped for g.-2518A>G MCP-1 polymorphism using amplification refractory mutation system- polymerase chain reaction.

RESULTS

The frequency of G allele was observed to be higher in T2D cases with ESRD (34.49%) compared to T2D cases without ESRD (24.39%) and controls (31.67%). Under the dominant model, G allele increased the risk of ESRD by 1.68-fold [p = 0.047, OR = 1.68 (1.0-2.79) at 95% CI].

CONCLUSION

MCP-1 -2518 GG genotype and G allele may increase the risk of progression to ESRD in T2D cases.

Genetic variants of the monocyte chemoattractant protein-1 gene and its receptor CCR2 and risk of coronary artery disease: a meta-analysis

OBJECTIVE

Monocyte chemoattractant protein-1 (MCP-1) and its receptor chemokine (C-C motif) receptor 2 (CCR2) are implicated in promoting atherosclerosis. Many studies have searched the association between variants of the MCP-1 gene or CCR2 gene and risk of coronary artery disease (CAD), but the results are inconsistent.

METHODS

We conducted a meta-analysis of 20 publications including 24 studies on 2 genetic variants [A-2518G in the MCP-1 and V64I in the CCR2] published before January 2011, including a total of 9844 patients with CAD and 11,821 controls. Publication bias and heterogeneity among studies were explored.

RESULTS

In a combined analysis, the pooled OR for CAD of the -2518G allele was 1.42 (95%CI: 1.06-1.92) compared to wild-type A allele under a recessive model in Caucasian group, but there is an indication of publication bias and heterogeneity among the 9 studies. When the analyses were restricted to 2 large studies (n≥500 cases), the pooled OR was 1.08 (95%CI: 0.85-1.37). Our analyses detected a possibility of publication bias with an overestimate of the true association by smaller studies. A meta-analysis of studies on the CCR2 V64I variant showed no significant association with CAD, the pooled OR of 64I was 1.27 (95%CI: 0.81-1.99) in recessive model and 1.06 (95%CI: 0.95-1.19) in dominant model, respectively.

CONCLUSIONS

The results indicate that MCP-1-2518G allele had probably increased risk of CAD in Caucasian but this is likely to be due to publication bias and insufficient sample size. The CCR2 V64I has not been found any association with CAD.

Association of interleukin-6 gene polymorphism with angina pectoris

In this study, we investigated the role of the -174G>C polymorphism of interleukin-6 (IL-6) as a predisposing factor to angina pectoris. Patients were separated into 2 groups: angina (N = 72) and nonangina (N = 71). There were no statistical differences between groups for all cardiovascular risk factors evaluated. The GG genotype frequency was 18% lower in the angina than in the non-angina group, whereas GC + CC was 18% higher in the angina group (P = .036). The frequency of G allele was 11% lower in the angina than in the nonangina group and C allele was 11% higher in the angina group (P = .043). Patients carrying the C allele showed a 2-fold increased risk for angina pectoris (P = .036). Our study demonstrates a high incidence of the -174G>C polymorphism of the IL-6 gene in patients with angina pectoris compared with those carrying the G allele, reinforcing the contribution of genetic factors to the symptoms of angina pectoris.

Monocyte chemoattractant protein 1-2518 A/G polymorphism and susceptibility to type 2 diabetes in a Chinese population

BACKGROUND

Hyperglycemia could accelerate monocyte chemoattractant protein 1 (MCP-1) production in monocytes and vascular endothelial cells. Recently, a genetic polymorphism (-2518 A/G) located in MCP-1 gene promoter has been found that could influence the expression of MCP-1. A large cohort study of Caucasians reported that MCP-1 G-2518 gene variant was negatively correlated with the prevalence of insulin resistance and type 2 diabetes. However, it is unclear whether this polymorphism is associated with type 2 diabetes in Han Chinese.

METHODS

We conducted a population-based case-control study of 416 type 2 diabetes cases and 416 controls.

RESULTS

Compared with the wild genotype AA, MCP-1 G-2518 gene variant could significantly decrease the prevalence of type 2 diabetes in Han Chinese (adjusted OR=0.49, 95% CI 0.32-0.77, P<0.0001). The results of stratified analyses indicated that a decreased risk of type 2 diabetes related with variant genotypes was evident in younger participants (age ≤50) (adjusted OR=0.35, 95% CI 0.20-0.61, P<0.0001), and similar results were observed in males (adjusted OR=0.37, 95% CI 0.21-0.66, P=0.001) and urban participants (adjusted OR=0.35, 95% CI 0.21-0.58, P<0.0001). In addition, a statistically significant difference was observed between MCP-1-2518 A/G polymorphism and waist to hip ratio.

CONCLUSIONS

Our present pilot study indicated that MCP-1 G-2518 gene variant could significantly decrease the risk of type 2 diabetes in a Chinese population.