Variants in matrix metalloproteinase-9 gene are associated with hemorrhagic transformation in acute ischemic stroke patients with atherothrombosis, small artery disease, and cardioembolic stroke

Influence of matrix metalloproteinase 9 variant rs17576 on ischemic stroke risk and severity in acute coronary syndrome

BACKGROUND

Ischemic injury is a common mechanism in both ischemic stroke (IS) and acute coronary syndrome (ACS). Matrix metalloproteinase 9 (MMP-9), an endopeptidase that degrades extracellular matrix, is important in the pathogenesis of IS. The purpose of this study is to evaluate the association between the SNP rs17576 in MMP-9 gene with (1) the risk and severity of acute ischemic stroke in Saudi Arab individuals with recent acute coronary syndrome, and (2) the risk of acute coronary syndrome in Saudi Arab individuals without ischemic stroke.

METHODS

A case control study of 200 IS patients, 520 ACS patients (without IS), and 500 aged-matched healthy controls were genotyped to detect the MMP-9 polymorphism rs17156.

RESULTS

Our study demonstrated a non-significant difference in the genotype and allele frequencies of the MMP9 rs17576 polymorphism between the patients with IS and patients with ACS without IS (P = 0.31 for the GA genotype, 0.25 for the AA genotype and P = 0.20 for the A allele). AA genotype was found to be statistically significant between IS and control groups; [OR=1.84, 95 % CI (1.08-3.14), p =0.015]. A allele showed a significant difference between the two groups [OR=1.28, 95 % CI (1.00-1.64), p =0.028]. By comparing ACS without IS and controls, AA genotype was significant [OR=1.46, 95 % CI (1.01-2.12), p =0.029]. Stratification by NIHSS score revealed higher mortality and early neurologic deterioration in IS patients with NIHSS score ≥ 16 (p < 0.001, 0.044 respectively).

CONCLUSION

We deduced the lack of association either with allele or genotype frequencies (p>0.05) between the IS cases and the cases of ACS without IS. In contrast there was a significant association of mutant genotype AA between either the IS group or ACS (without IS) group, and the control group. In addition, different rs17576 genotypes were not associated with raised mortality or a tendency to develop early neurologic deterioration.

Does the functional polymorphism-1562C/T of MMP-9 gene influence brain disorders?

Metalloproteinase-9 (MMP-9) is one of the most strongly expressed matrix metalloproteinases (MMPs) in the brain. The MMP-9 activity in the brain is strictly regulated, and any disruptions in this regulation contribute to a development of many disorders of the nervous system including multiple sclerosis, brain strokes, neurodegenerative disorders, brain tumors, schizophrenia, or Guillain-Barré syndrome. This article discusses a relationship between development of the nervous system diseases and the functional single nucleotide polymorphism (SNP) at position -1562C/T within the MMP-9 gene. A pathogenic influence of MMP-9-1562C/T SNP was observed both in neurological and psychiatric disorders. The presence of the allele T often increases the activity of the MMP-9 gene promoter and consequently the expression of MMP-9 when compared to the allele C. This leads to a change in the likelihood of an occurrence of diseases and modifies the course of certain brain diseases in humans, as discussed below. The presented data indicates that the MMP-9-1562C/T functional polymorphism influences the course of many neuropsychiatric disorders in humans suggesting a significant pathological role of the MMP-9 metalloproteinase in pathologies of the human central nervous system.

ALDH2 rs671 Polymorphism Likely a Risk Factor for Hemorrhagic Stroke: A Hospital-Based Study

Background

Hypertension is the main risk factor for hemorrhagic stroke. Aldehyde dehydrogenase 2 (ALDH2) may inhibit the occurrence of hypertension by anti-oxidative stress and vascular dilation. The purpose was to investigate the relationship of ALDH2 polymorphisms with hemorrhagic stroke in Hakka Chinese.

Methods

A total of 329 patients with hemorrhagic stroke and 515 controls were enrolled, and medical records (smoking and drinking history, hypertension, and diabetes) were collected. The genotypes of ALDH2 rs671 of the two groups were detected and analyzed.

Results

The proportion of the ALDH2 rs671 G/G, G/A, and A/A genotype in patients with hemorrhagic stroke was 55.9%, 37.4%, and 6.7%, respectively, while those were 65.0%, 30.7%, and 4.3% in controls, respectively. There was statistically significant difference in ALDH2 rs671 genotypes distribution (P=0.021) and alleles distribution (P=0.005) between patients and controls. Among hemorrhagic stroke patients, no statistically significant differences were observed between patients with ALDH2 different genotypes. Logistic regression analysis showed that there was significantly high risk of hemorrhagic stroke in men (male vs female: adjusted OR 1.711, 95% CI 1.154-2.538, P=0.008), the presence of hypertension (with vs without hypertension: adjusted OR 16.095, 95% CI 10.958-23.641, P<0.001), and the presence of ALDH2 rs671 G/A genotype (G/A vs G/G: adjusted OR 1.679, 95% CI 1.151-2.450, P=0.007) or A/A genotype (A/A vs G/G: adjusted OR 2.516, 95% CI 1.132-5.591, P=0.024).

Conclusion

ALDH2 rs671 polymorphism likely a risk factor for hemorrhagic stroke.

MMP9 SNP and MMP SNP-SNP interactions increase the risk for ischemic stroke in the Han Hakka population

OBJECTIVES

To investigate the association of eight variants of four matrix metalloproteinase (MMP) genes with ischemic stroke (IS) and whether interactions among these single nucleotide polymorphisms (SNPs) increases the risk of IS.

METHODS

Among 547 patients with ischemic stroke and 350 controls, matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to examine eight variants arising from four different genes, including MMP-1 (rs1799750), MMP-2 (rs243865, rs2285053, rs2241145), MMP-9 (rs17576), and MMP-12 (rs660599, rs2276109, and rs652438). Gene-gene interactions were employed using generalized multifactor dimensionality reduction (GMDR) methods.

RESULTS

The frequency of rs17576 was significantly higher in IS patients than in controls (p = .033). Logistic regression analysis revealed the AG and GG genotypes of rs17576 to be associated with a higher risk for IS, with the odds ratio and 95% confidence interval being 2.490 (1.251-4.959) and 2.494 (1.274-4.886), respectively. GMDR analysis showed a significant SNP-SNP interaction between rs17576 and rs660599 (the testing balanced accuracy was 53.70% and cross-validation consistency was 8/10, p = .0107). Logistic regression analysis showed the interaction between rs17576 and rs660599 to be an independent risk factor for IS with an odds ratio of 1.568 and a 95% confidence interval of 1.152-2.135.

CONCLUSION

An MMP-9 rs17576 polymorphism is associated with increased IS risk in the Han Hakka population and interaction between MMP-9 rs17576 and MMP-12 rs660599 is associated with increased IS risk as well.

Acute Inflammation in Cerebrovascular Disease: A Critical Reappraisal with Focus on Human Studies

Recent attention has been focused on the field of inflammatory biomarkers associated with vascular disorders, regarding diagnosis, prognosis, and possible therapeutical targets. In this study, we aimed to perform a comprehensive review of the literature regarding the use of inflammatory biomarkers in stroke patients. We searched studies that evaluated inflammation biomarkers associated with Cerebrovascular Disease (CVD), namely, ischemic Stroke (IS), Intracerebral Hemorrhage (ICH) and Cerebral Venous Thrombosis (CVT). As of today, neutrophil–lymphocyte ratio (NLR) seems the be the most widely studied and accepted biomarker for cerebrovascular disease due to its easy access and availability. Although demonstrated as a prognostic risk factor, in IS, ICH and CVT, its diagnostic role is still under investigation. Several other prognostic factors could be used or even combined together into a diagnostic or prognostic index. Multiple inflammatory biomarkers appear to be involved in IS, ICH, and CVT. Blood inflammatory cells, easily measured and accessible at admission may provide information regarding accurate diagnosis and prognosis. Although not yet a reality, increasing evidence exists to suggest that these may become potential therapeutic targets, likely influencing or mitigating complications of CVD and improving prognosis. Nevertheless, further larger, well-designed randomized clinical trials are still needed to follow up this hypothesis.

TT genotype of the MMP-9-1562C/T polymorphism may be a risk factor for thrombolytic therapy-induced hemorrhagic complications after acute ischemic stroke

INTRODUCTION

Levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) influence recombinant tissue plasminogen activator (rtPA) therapy response in patients with acute ischemic stroke (AIS). Serum levels of MMPs and TIMPs along with the expression of genes coding these proteins are related to the recovery and appearance of adverse effects (AE) after AIS. Consequently, it is important to explore whether polymorphisms in regulatory sequences of MMPs and TIMPs are associated with rtPA response in AIS patients.

OBJECTIVES

To determine whether selected polymorphic variants within MMP-2, MMP-9, and TIMP-2 genes may influence rtPA therapy response with regard to outcomes in patients with AIS and the occurrence of AE.

METHODS

Our study included 166 patients suffering AIS, treated with rtPA. Patients' recovery was estimated using the Modified Rankin Scale (mRS) 3 months after the AIS occurred. Favorable outcome was defined with scores 0-1 and poor outcome with scores 2-6. Genotyping was performed using real-time PCR (rs243866, rs243865, rs243864, rs2277698, and rs8179090) and PCR-RFLP (rs2285053, rs3918242) methods. Additionally, rtPA AE were followed during the hospitalization.

RESULTS

There was no significant association between genotypes and alleles of selected polymorphisms and rtPA therapy response measured through the decrease of the mRS score in patients with AIS. Intracranial hemorrhage, as well as parenchymal hematoma type 2, was significantly more frequent in patients with TT genotype of the MMP-9-1562C/T polymorphism (p = 0.047, p = 0.011, respectively). Patients with intracranial hemorrhages after rtPA were significantly more likely to have the TT genotype of TIMP-2-303C/T polymorphism and the TT genotype of MMP-9-1562C/T polymorphism (p < 0.001).

CONCLUSION

TT genotype of the MMP-9-1562C/T polymorphism may be a risk factor for rtPA-induced hemorrhagic complications after AIS.

Association of Matrix Metalloproteinase 9 and Cellular Fibronectin and Outcome in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Introduction: The role of matrix metalloproteinase 9 (MMP-9) and cellular fibronectin (c-Fn) in acute ischemic stroke is controversial. We systematically reviewed the literature to investigate the association of circulating MMP-9 and c-Fn levels and MMP-9 rs3918242 polymorphism with the risk of three outcome measures after stroke.

Methods: We searched English and Chinese databases to identify eligible studies. Outcomes included severe brain edema, hemorrhagic transformation, and poor outcome (modified Rankin scale score ≥3). We estimated standardized mean differences (SMDs) and pooled odds ratios (ORs) with 95% confidence intervals (CIs).

Results: Totally, 28 studies involving 7,239 patients were included in the analysis of circulating MMP-9 and c-Fn levels. Meta-analysis indicated higher levels of MMP-9 in patients with severe brain edema (SMD, 0.76; 95% CI, 0.18–1.35; four studies, 419 patients) and hemorrhagic transformation (SMD, 1.00; 95% CI, 0.41–1.59; 11 studies, 1,709 patients) but not poor outcome (SMD, 0.30; 95% CI, −0.12 to 0.72; four studies, 759 patients). Circulating c-Fn levels were also significantly higher in patients with severe brain edema (SMD, 1.55; 95% CI, 1.18–1.93; four studies, 419 patients), hemorrhagic transformation (SMD, 1.75; 95% CI, 0.72–2.78; four studies, 458 patients), and poor outcome (SMD, 0.46; 95% CI, 0.16–0.76; two studies, 210 patients). Meta-analysis of three studies indicated that the MMP-9 rs3918242 polymorphism may be associated with hemorrhagic transformation susceptibility under the dominant model (TT + CT vs. CC: OR, 0.621; 95% CI, 0.424–0.908; P = 0.014). No studies reported the association between MMP-9 rs3918242 polymorphism and brain edema or functional outcome after acute stroke.

Conclusion: Our meta-analysis showed that higher MMP-9 levels were seen in stroke patients with severe brain edema and hemorrhagic transformation but not poor outcome. Circulating c-Fn levels appear to be associated with all three outcomes including severe brain edema, hemorrhagic transformation, and poor functional outcome. The C-to-T transition at the MMP-9 rs3918242 gene appears to reduce the risk of hemorrhagic transformation.

MMP9 rs17576 Is Simultaneously Correlated with Symptomatic Intracranial Atherosclerotic Stenosis and White Matter Hyperintensities in Chinese Population

PURPOSE

The aim of this study was screening for single nucleotide polymorphisms (SNPs) associated with white matter hyperintensities (WMHs) in symptomatic intracranial atherosclerotic stenosis (sICAS) patients and exploring a possible connection in the genetic background between macrovascular disease and small vessel disease.

METHODS

There were 400 sICAS patients enrolled in the study. Fazekas scores were applied to WMH classification. Healthy controls were referred to 1,000 Genome Project and GeneSky company who provided 1,007 Chinese healthy controls. Fast target sequencing technology was used to select the SNPs of 102 genes related to the pathogenesis of sICAS in the sICAS patients.

RESULTS

The allele frequencies of 88 SNPs were significantly different between the sICAS group and the healthy controls (p < 0.05). The allele frequencies of 53 SNPs were significantly different between the sICAS patients with and without WMHs (p < 0.05). Further analysis found that matrix metalloproteinase 9 (MMP9) rs17576 was simultaneously related to sICAS and WMHs. The frequency of the rs17576 A allele was significantly lower in sICAS patients when compared to the normal controls (p = 0.03, OR [95% CI] = 0.75 [0.625-0.91]). Also, the frequency of the rs17576 genotypes was significantly different under codominant (p = 0.009), dominant (p = 0.014), and recessive (p= 0.023) models. The frequency of the rs17576 A allele was significantly higher in sICAS with WMH patients, compared to those without WMHs (p = 0.022, OR [95% CI] = 1.54 [1.06-2.22]); the frequency of the rs17576 genotypes was significantly different under codominant (p = 0.019) and recessive (p = 0.032) models. Logistic regression analysis showed that age, hypertension, and MMP9 rs17576 AA genotype were independent risk factors for sICAS with WMHs.

CONCLUSION

MMP9 rs17576 may be simultaneously associated with the risk of sICAS and WMHs.

Early Electroacupuncture Extends the rtPA Time Window to 6 h in a Male Rat Model of Embolic Stroke via the ERK1/2-MMP9 Pathway

Background. Recombinant tissue plasminogen activator (rtPA) is the only recommended pharmacological treatment for acute ischemic stroke, but it has a restricted therapeutic time window. When administered at time points greater than 4.5 h after stroke onset, rtPA disrupts the blood-brain barrier (BBB), which leads to serious brain edema and hemorrhagic transformation. Electroacupuncture (EA) exerts a neuroprotective effect on cerebral ischemia; however, researchers have not clearly determined whether EA increases the safety of thrombolysis and extends the therapeutic time window of rtPA administration following ischemic stroke. Objective. The present study was conducted to test the hypothesis that EA extends the therapeutic time window of rtPA for ischemic stroke in a male rat model of embolic stroke. Methods. SD rats were randomly divided into the sham operation group, model group, rtPA group, EA+rtPA group, and rtPA+MEK1/2 inhibitor group. An injection of rtPA was administered 6 h after ischemia. Rats were treated with EA at the Shuigou (GV26) and Neiguan (PC6) acupoints at 2 h after ischemia. Neurological function, infarct volume, BBB permeability, brain edema, and hemorrhagic transformation were assessed at 24 h after ischemia. Western blotting and immunofluorescence staining were performed to detect the levels of proteins involved in the ERK1/2 signaling pathway (MEK1/2 and ERK1/2), tight junction proteins (Claudin5 and ZO-1), and MMP9 in the ischemic penumbra at 24 h after stroke. Results. Delayed rtPA treatment aggravated hemorrhagic transformation and brain edema. However, treatment with EA plus rtPA significantly improved neurological function and reduced the infarct volume, hemorrhagic transformation, brain edema, and EB leakage in rats compared with rtPA alone. EA increased the levels of tight junction proteins, inhibited the activation of the ERK1/2 signaling pathway, and reduced MMP9 overexpression induced by delayed rtPA thrombolysis. Conclusions. EA potentially represents an effective adjunct method to increase the safety of thrombolytic therapy and extend the therapeutic time window of rtPA administration following ischemic stroke. This neuroprotective effect may be mediated by the inhibition of the ERK1/2-MMP9 pathway and alleviation of the destruction of the BBB.

Dataset of allele and genotype frequencies of the three functionally significant polymorphisms of the MMP genes in Russian patients with primary open-angle glaucoma, essential hypertension and peptic ulcer

Data on the allele and genotype frequencies of the three functionally significant single nucleotide polymorphisms (SNPs) of the matrix metalloproteinases (MMP) genes (rs1799750 MMP1, rs3918242 and rs17576 MMP9) in Russian patients with primary open-angle glaucoma (POAG), essential hypertension (EH) and peptic ulcer (PU) are presented. Association studies identified these SNPs as possible significant markers associated with many multifactorial disorders, including POAG, EH, and PU. The frequencies of alleles and genotypes of the three SNPs in Russian patients with POAG, EH, and PU were presented separately for the entire study sample, females, and males, respectively. The data can be used as a reference for the Russian population.

Heavy Metal-Induced Cerebral Small Vessel Disease: Insights into Molecular Mechanisms and Possible Reversal Strategies

Heavy metals are considered a continuous threat to humanity, as they cannot be eradicated. Prolonged exposure to heavy metals/metalloids in humans has been associated with several health risks, including neurodegeneration, vascular dysfunction, metabolic disorders, cancer, etc. Small blood vessels are highly vulnerable to heavy metals as they are directly exposed to the blood circulatory system, which has comparatively higher concentration of heavy metals than other organs. Cerebral small vessel disease (CSVD) is an umbrella term used to describe various pathological processes that affect the cerebral small blood vessels and is accepted as a primary contributor in associated disorders, such as dementia, cognitive disabilities, mood disorder, and ischemic, as well as a hemorrhagic stroke. In this review, we discuss the possible implication of heavy metals/metalloid exposure in CSVD and its associated disorders based on in-vitro, preclinical, and clinical evidences. We briefly discuss the CSVD, prevalence, epidemiology, and risk factors for development such as genetic, traditional, and environmental factors. Toxic effects of specific heavy metal/metalloid intoxication (As, Cd, Pb, Hg, and Cu) in the small vessel associated endothelium and vascular dysfunction too have been reviewed. An attempt has been made to highlight the possible molecular mechanism involved in the pathophysiology, such as oxidative stress, inflammatory pathway, matrix metalloproteinases (MMPs) expression, and amyloid angiopathy in the CSVD and related disorders. Finally, we discussed the role of cellular antioxidant defense enzymes to neutralize the toxic effect, and also highlighted the potential reversal strategies to combat heavy metal-induced vascular changes. In conclusion, heavy metals in small vessels are strongly associated with the development as well as the progression of CSVD. Chelation therapy may be an effective strategy to reduce the toxic metal load and the associated complications.

Variants in matrix metalloproteinase-9 gene are associated with hemorrhagic transformation in acute ischemic stroke patients with atherothrombosis, small artery disease, and cardioembolic stroke

OBJECTIVE

The potential effect of matrix metalloproteinase-9 (MMP-9) variants and these variants interactions on hemorrhagic transformation (HT) risk after ischemic stroke (IS) remain unclear. The aims of present study were to investigate the associations of six variants in MMP-9 with HT, and these variants interactions whether related to increased HT risk.

METHOD

A total of 705 patients with IS who were admitted to the participating hospitals within 48 hr of symptom onset were consecutively enrolled between March 2014 and December 2016. HT was confirmed by brain computed tomography (CT) scan during 14 days from stroke onset. Six variants of MMP-9 gene were measured by mass spectrometry. Interactions of gene variant-gene variant were assessed through generalized multifactor dimensionality reduction method (GMDR).

RESULTS

HT occurred in 104 (14.8%) patients. There were no differences in genotypes for the six variants between patients with and without HT using univariate analysis (all p > 0.05). GMDR analysis revealed that there was a synergistic effect of gene variant-gene variant interactions between rs3918242 and rs3787268 in MMP-9 gene. Cox regression analysis showed that high-risk interactions of rs3918242 and rs3787268 were associated with increased risk of HT after adjusting for covariates (hazard ratio: 2.08; 95% confidence interval: 1.34-7.85; p = 0.016).

CONCLUSION

Incidence of HT is common in acute IS in Chinese population. The mechanisms leading to HT are most likely multifactorial. Two-loci interactions of rs3918242 and rs3787268 in MMP-9 gene may confer a higher risk for HT.