Monocyte chemoattractant protein (MCP-1) A-2518G gene polymorphism in stroke patients with different comorbidities

Ex vivo coronary endothelial cell activation associated with indoor coal combustion initiated atherosclerosis

Plenty of rural populations still chronically exposed to indoor coal burning, which tremendously raises the risk of cardiovascular disease, in China. This study aimed to further investigate the association between indoor coal burning exposure and atherosclerotic cardiovascular diseases to search for relevant markers for disease prevention. Herein, we conducted a cross-sectional study, carried out on 752 local long-term residents with or without bituminous coal for cooking and heating indoor, in Nangong County, Hebei Province, China. We utilized a nearest neighbor propensity score match (PSM) with a caliper distance equal to 0.001 to eliminate bias caused by confounding factors. The expression of genes associated with endothelial activation (CCL2, CCL5, CXCL8, CXCL12, VCAM, ICAM, SELP) in primary human coronary artery endothelial cells (HCAECs) were quantified through ex vivo biosensor assay. Multiple linear regression models with stratification analyses by gender and binary logit regression models were used to evaluate the association between mRNA expression of biosensor genes and indoor coal burning pollution or carotid atherosclerosis, respectively. Protein secretion level was detected by enzyme-linked immunosorbent assay (ELISA). The prevalence of carotid atherosclerosis in exposure group was higher than control (P = 0.023), before PSM. The gene expression of CCL2 in exposure group was significantly higher than control (P = 0.002). Indoor coal burning exposure was correlated with gene expression of CCL2 (β = 3.45, 95 % CI: 0.04-6.87, P = 0.047) and CXCL8 (β = 1.25, 95 % CI: 0.02-2.49, P = 0.046) in female. A higher risk of carotid atherosclerosis was observed in the same as the increase expression of CCL2 (OR = 1.07, 95 % CI: 1.01-1.14, P = 0.020). In conclusion, prolonged exposure to indoor coal burning could elevate the gene expression of CCL2 by activating vascular endothelial cells and was relative to the initiation of carotid atherosclerosis.

Upregulated C-C Motif Chemokine Ligand 2 Promotes Ischemic Stroke via Chemokine Signaling Pathway

BACKGROUND

This study aims to evaluate the potential effect and the underlying mechanism of C-C motif chemokine ligand 2 (CCL2) in ischemic stroke.

METHODS

An integrated bioinformatics analysis was performed to identify the differentially expressed (DE) genes and their related pathways in ischemic stroke. In vivo study of a rat model of middle cerebral artery occlusion (MCAO) was further established to assess the effect of CCL2 on severity of neurologic impairments. The expression levels of proinflammatory cytokines were also evaluated using the ELISA assay, and Western blot was also used to determine the expression of CCL2 and other DE proteins in the related pathways.

RESULTS

A total of 88 DE genes were identified from the microarray dataset of ischemic stroke. The bioinformatics analysis revealed that CCL2 was highly expressed in ischemic stroke tissue and promoted the ischemic stroke progression via activation of the chemokine signaling pathway and cytokine-cytokine receptor interaction pathway. The in vivo study of the ischemic stroke rat model also showed that the CCL2 expression was elevated in the MCAO/R rats, with significant neurological impairments and ischemic infarct area in the brain tissue being observed. The administration of CCL2 inhibitors significantly inhibited the inflammatory response, attenuated the neurological impairments, and decreased the ischemic infarct area in the MCAO/R rats. Furthermore, the downregulation of CCL2 also inhibited the expression of the pathway-related proteins including CCL7, CCR2, CXCL16, and TNF-α.

CONCLUSIONS

These results indicate that the CCL2/chemokine signaling pathway is responsible for ischemic stroke progression and might represent a potential therapeutic target for ischemic stroke treatment.

Design and optimization of crocetin loaded PLGA nanoparticles against diabetic nephropathy via suppression of inflammatory biomarkers: a formulation approach to preclinical study

Diabetic nephropathy (DN) is a serious complication of diabetes mellitus whose expand process is linked with the fibrosis, renal hypertrophy and inflammation. The current study was to formulate and optimize the nano-formulation of crocetin (CT-PLGA-NPs) against Streptozotocin-induced renal nephropathy in rats. Double emulsion evaporation technique was used for the preparation of CT-PLGA-NPs. CT-PLGA-NPs were scrutinized for polydispersity index, size, gastric stability, entrapment, drug-loading capacity and in-vitro drug release and in vivo preclinical study. Single intraperitoneal injection of streptozotocin (STZ) (55 mg/kg) and rats were divided into different group. Renal function and metabolic parameters of urine and serum were estimated. Fibrotic protein, renal pro-inflammatory cytokines and degree of renal damage expression were also determined. We also estimated the fibronectin, type IV collagen and transforming growth factor-β1 for a possible mechanism of action. Crocetin supplement (10 mg/kg) and CT-PLGA-NPs exhibited the accumulation of the drug in kidney and liver of diabetic rats. Crocetin reduced the BGL and enhanced plasma insulin and body weight. Dose dependent treatment of crocetin significantly (p < .001) down-regulated the expression of renal tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin (IL)-1β (IL-1β) and Monocyte Chemoattractant Protein-1 (MCP-1). Crocetin significantly (p < .001) altered the expression of fibronectin, type IV collagen, and transforming growth factor-β1 (TGF-1β). Crocetin significantly (p < .001) down-regulated the protein kinase C activity and the expression of nuclear factor κB (NF-κB) p65 activity and protein production in renal tissue. On the basis of the available result, we can conclude that nano-formulation of crocetin could attenuate the diabetic nephropathy via antifibrotic and anti-inflammatory effect.

Cerebrovascular Gene Expression in Spontaneously Hypertensive Rats After Transient Middle Cerebral Artery Occlusion

Hypertension is a major risk factor for stroke, which is one of the leading global causes of death. In the search for new and effective therapeutic targets in stroke research, we need to understand the influence of hypertension in the vasculature following stroke. We used Affymetrix whole-transcriptome expression profiling as a tool to address gene expression differences between the occluded and non-occluded middle cerebral arteries (MCAs) from spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats after transient middle cerebral artery occlusion (tMCAO), to provide clues about the pathological mechanisms set in play after stroke. Verified by quantitative PCR, expression of Ccl2, Edn1, Tgfβ2, Olr1 and Serpine1 was significantly increased in the occluded compared to non-occluded MCAs from both SHRs and WKY rats. Additionally, expression of Mmp9, Icam1, Hif1α and Timp1 was increased in the occluded compared to non-occluded MCAs isolated from WKY rats. In comparison between occluded MCAs from SHRs versus occluded MCAs from WKY rats, expression of Ccl2, Olr1 and Serpine1 was significantly increased in SHR MCAs. However, the opposite was observed regarding expression of Edn1. Thus these data suggest that Ccl2, Edn1, Tgfβ2, Olr1 and Serpine1 may be possible mediators of the vascular changes in the occluded MCAs from both SHRs and WKY rats after tMCAO. The aforementioned genes possess biological functions that are consistent with early stroke injuries. In conclusion, these genes may be potential targets in future strategies for acute stroke treatments that can be used in patients with and without hypertension.

Cellular connections, microenvironment and brain angiogenesis in diabetes: Lost communication signals in the post-stroke period

Diabetes not only increases the risk but also worsens the motor and cognitive recovery after stroke, which is the leading cause of disability worldwide. Repair after stroke requires coordinated communication among various cell types in the central nervous system as well as circulating cells. Vascular restoration is critical for the enhancement of neurogenesis and neuroplasticity. Given that vascular disease is a major component of all complications associated with diabetes including stroke, this review will focus on cellular communications that are important for vascular restoration in the context of diabetes. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.

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.

Interplay between brain stem angiotensins and monocyte chemoattractant protein-1 as a novel mechanism for pressor response after ischemic stroke

Pressor response after stroke commonly leads to early death or susceptibility to stroke recurrence, and detailed mechanisms are still lacking. We assessed the hypothesis that the renin-angiotensin system contributes to pressor response after stroke by differential modulation of the pro-inflammatory chemokine monocyte chemoattractant protein-1 (MCP-1) in the rostral ventrolateral medulla (RVLM), a key brain stem site that maintains blood pressure. We also investigated the beneficial effects of a novel renin inhibitor, aliskiren, against stroke-elicited pressor response. Experiments were performed in male adult Sprague-Dawley rats. Stroke induced by middle cerebral artery occlusion elicited significant pressor response, accompanied by activation of angiotensin II (Ang II)/type I receptor (AT1R) and AT2R signaling, depression of Ang-(1-7)/MasR and Ang IV/AT4R cascade, alongside augmentation of MCP-1/C-C chemokine receptor 2 (CCR2) signaling and neuroinflammation in the RVLM. Stroke-elicited pressor response was significantly blunted by antagonism of AT1R, AT2R or MCP-1/CCR2 signaling, and eliminated by applying Ang-(1-7) or Ang IV into the RVLM. Furthermore, stroke-activated MCP-1/CCR2 signaling was enhanced by AT1R and AT2R activation, and depressed by Ang-(1-7)/MasR and Ang IV/AT4R cascade. Aliskiren inhibited stroke-elicited pressor response via downregulating MCP-1/CCR2 activity and reduced neuroinflammation in the RVLM; these effects were potentiated by Ang-(1-7) or Ang IV. We conclude that whereas Ang II/AT1R or Ang II/AT2R signaling in the brain stem enhances, Ang-(1-7)/MasR or Ang IV/AT4R antagonizes pressor response after stroke by differential modulations of MCP-1 in the RVLM. Furthermore, combined administration of aliskiren and Ang-(1-7) or Ang IV into the brain stem provides more effective amelioration of stroked-induced pressor response.

Correlations of MCP-1 -2518A>G polymorphism and serum levels with cerebral infarction risk: a meta-analysis

This meta-analysis was performed to evaluate the relationships between the monocyte chemoattractant protein-1 (MCP-1) -2518A>G (rs1024611 A>G) polymorphism and its serum levels, and the risk of cerebral infarction. The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched for relevant articles published before October 1st, 2013 without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratios (ORs) or standardized mean difference (SMD) with their 95% confidence intervals (95% CIs) were calculated. Twelve case-control studies that met all the inclusion criteria were included in this meta-analysis. A total of 1272 patients with cerebral infarction and 1210 healthy control subjects were involved in this meta-analysis. Our meta-analysis results reveal that the MCP-1 -2518A>G polymorphism might increase the risk of cerebral infarction (A allele vs. G allele: OR=1.37, 95% CI: 1.18-1.60, p<0.001; GA+AA vs. GG: OR=1.33, 95% CI: 1.09-1.62, p=0.005; respectively). Furthermore, cerebral infarction patients had higher levels of serum MCP-1 than did healthy control subjects (SMD=2.96, 95% CI: 2.00-3.92, p<0.001). Statistical analysis revealed no evidence of publication bias in this meta-analysis (all p>0.05). Our findings indicate that the MCP-1 -2518A>G polymorphism and serum MCP-1 levels may contribute to the development of cerebral infarction. Thus, the MCP-1 -2518A>G polymorphism and serum MCP-1 levels could be potential biomarkers for the early detection of cerebral infarction.

Association of oxysterol binding protein-related protein 9 polymorphism with cerebral infarction in Hunan Han population

BACKGROUND

Oxysterol binding protein-related protein 9 (ORP9) may be related to the pathogenesis of cerebral infarction since it is closely related with glucose and lipid metabolism. The present study was designed to investigate the genetic relationship between ORP9 gene polymorphisms and cerebral infarction (CI) in Hunan Han population.

METHODS

Total 544 cerebral infarction patients (60.0 ± 10.3 years) and 284 healthy controls (59.0 ± 9.5 years) were enrolled. Sociodemographic and clinical data of the subjects, such as age, gender, body mass index, smoking, drinking, diabetes mellitus, hypertension, systolic and diastolic blood pressures, fasting blood glucose, triglycerides, total cholesterol, low-density and high-density lipoprotein were recorded, and two single-nucleotide polymorphisms (SNPs) of ORP9 gene including rs856600 and rs768529 with high mutation annotation format (MAF) values of 0.103 and 0.485 were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

No statistical difference was observed in allele distributions and frequencies of the two SNPs between control and CI groups. However, the percentage of atherosclerosis in CI group was significantly higher than that in the control group (p < 0.001). The frequencies of the TT genotype and T allele of rs768529 were significantly higher in patients with vulnerable plaque than those in patients with stable plaque (p < 0.001, p = 0.002). Logistic association analysis showed no correlations between cerebral infarction and different alleles (p > 0.05).

CONCLUSION

T allele of rs768529 may be a risk factor for the formation of the carotid vulnerable plaque in Chinese Hunan Han population.

Functional genetic polymorphisms of monocyte chemoattractant protein 1 and C-C chemokine receptor type 2 in ischemic stroke

Recent findings indicated that monocyte chemoattractant protein 1 (MCP1) and its C-C chemokine receptor type 2 (CCR2) play a key role in ischemic stroke (IS) progression. This study was aimed at evaluating the potential association of the MCP1 gene (MCP1) rs1024611 (-2518 A>G) and CCR2 gene (CCR2) rs1799864 (V64I; 190 G>A) functional single nucleotide polymorphisms (SNPs) with IS in the Armenian population. For the purpose of this study, genomic DNA samples of 100 patients with the first-episode IS and 115 healthy subjects (controls) were genotyped for the selected SNPs using a polymerase chain reaction with sequence-specific primers. The results obtained demonstrated that while the CCR2 rs1799864 SNP genotypes were equally distributed among patients and controls, the frequency and carriage rate of the of the MCP1 rs1024611*G minor allele were higher in patients. While a potential association between IS and CCR2 rs1799864 SNP was evaluated for the first time, the latest finding was in agreement with the earlier data reported for some other populations. In summary, this study revealed no association of CCR2 rs1799864 SNP with IS, and a positive association between G minor allele of MCP1 rs1024611 SNP and IS in the Armenian population. Based on the present and earlier reported data, we concluded that the minor G allele of the MCP1 rs1024611 SNP might be considered a risk factor for IS.

Association of inflammatory gene polymorphisms and conventional risk factors with arterial stiffness by age

Background

Inflammatory gene polymorphisms are potentially associated with atherosclerosis risk, but their age-related effects are unclear. To investigate the age-related effects of inflammatory gene polymorphisms on arterial stiffness, we conducted cross-sectional and 5-year follow-up studies using the cardio-ankle vascular index (CAVI) as a surrogate marker of arterial stiffness.

Methods

We recruited 1850 adults aged 34 to 69 years from the Japanese general population. Inflammatory gene polymorphisms were selected from NF-kB1, CD14, IL-6, IL-10, MCP-1, ICAM-1, and TNF-α. Associations of CAVI with genetic and conventional risk factors were estimated by sex and age group (34–49, 50–59, and 60–69 years) using a general linear model. The association with 5-year change in CAVI was examined longitudinally.

Results

Glucose intolerance was associated with high CAVI among women in all age groups, while hypertension was associated with high CAVI among participants in all age groups, except younger women. Mean CAVI for the CD14 CC genotype was lower than those for the TT and CT genotypes (P for trend = 0.005), while the CD14 polymorphism was associated with CAVI only among men aged 34 to 49 years (P = 0.006). No association of the other 6 polymorphisms with CAVI was observed. No association with 5-year change in CAVI was apparent.

Conclusions

Inflammatory gene polymorphisms were not associated with arterial stiffness. To confirm these results, further large-scale prospective studies are warranted.

Association of CXCL1 promoter polymorphism with ischaemic stroke in Korean population

This is a pilot study analysing association of chemokine gene polymorphisms (CXCL1, rs3117604; CXCL2, rs3806792; CCL2, rs2857656 and rs3760396; CCL5, rs2107538) in Korean patients with ischemic stroke (IS) (n = 120) and age-matched controls (n = 267). The CXCL1 gene and particularly T allele of rs3117604 was associated with IS.

Systemic immune activation shapes stroke outcome

Stroke is a major cause of morbidity and mortality, and activation of the immune system can impact on stroke outcome. Although the majority of research has focused on the role of the immune system after stroke there is increasing evidence to suggest that inflammation and immune activation prior to brain injury can influence stroke risk and outcome. With the high prevalence of co-morbidities in the Western world such as obesity, hypertension and diabetes, pre-existing chronic 'low-grade' systemic inflammation has become a customary characteristic of stroke pathophysiology that needs to be considered in the search for new therapies. The importance of the immune system in stroke has been demonstrated in a number of ways, both experimentally and in the clinical setting. This review will focus on the effect of immune activation arising from systemic inflammatory conditions and infection, how it affects the incidence and outcomes of stroke, and the possible underlying mechanisms involved. This article is part of a Special Issue entitled 'Neuroinflammation in neurodegeneration and neurodysfunction'.

Polymorphisms of integrin, alpha 6 contribute to the development and neurologic symptoms of intracerebral hemorrhage in korean population

OBJECTIVE

The extracellular matrix (ECM) and cell adhesion molecules play crucial roles in angiogenesis, apoptosis, thrombosis, and inflammation, and also contribute to the pathogenesis of stroke. Integrin, alpha 6 (ITGA6) is a member of ECM adhesion receptors. We investigated whether two single nucleotide polymorphisms (SNPs) (rs11895564, Ala380Thr; rs2293649, Asp694Asp) of ITGA6 were associated with the development and clinical phenotypes of intracerebral hemorrhage (ICH) and ischemic stroke (IS).

METHODS

We enrolled 199 stroke (78 ICH and 121 IS) and 291 control subjects. Stroke patients were divided into subgroups according to the scores of the National Institutes of Health Stroke Survey (NIHSS, <6 and ≥6) and Modified Barthel Index (MBI, <60 and ≥60). SNPStats, SNPAnalyzer, and Helixtree programs were used to calculate odds ratios, 95% confidence intervals, and p values. Multiple logistic regression models were used to analyze genetic data.

RESULTS

A missense SNP rs11895564 was associated with the development of ICH (p=0.026 in codominant2, p=0.013 in recessive, p=0.02 in log-additive models; p=0.041 in allele distributions). The A allele frequency of rs11895564 was higher in the ICH group (13.5%) than in the control group (8.1%). In the clinical phenotypes, rs11895564 and rs2293649 showed significant associations in the MBI scores of IS (p=0.014 in codominant1 model; p=0.02 in allele distributions) and NIHSS scores of ICH (p=0.017 in codominant2, p=0.035 in recessive, p=0.035 in log-additive models), respectively.

CONCLUSION

These results suggest that ITGA6 may be associated with the development and clinical phenotypes of stroke in Korean population.