Serum matrix metalloproteinase-3 concentration is influenced by MMP-3 -1612 5A/6A promoter genotype and associated with myocardial infarction

Inflammatory biomarkers and long-term outcome in young patients three months after a first myocardial infarction

BACKGROUND

Studies on predictive value of circulating inflammatory biomarkers after myocardial infarction (MI) have often been limited by blood sampling only in an acute setting and short follow-up time. We aimed to compare the long-term predictive value of nine inflammatory biomarkers, known to be involved in atherosclerosis, in young patients investigated three months after a first-time MI.

METHODS

Nine biomarkers (high-sensitivity C-reactive protein, interleukin (IL)-6, IL-18, monocyte chemoattractant protein-1, matrix metalloproteinase (MMP)-1, MMP-3, MMP-9, serum amyloid A and tumor necrosis factor-alfa) were sampled in 382 young (<60 years) patients and in age and sex-matched controls, three months after a first-time MI between 1996 and 2000. Swedish national patient registers were used to determine cardiovascular (CV) outcomes during 20 years of follow-up.

RESULTS

In cases, random forest models identified IL-6 as the most important predictor of the primary composite endpoint of death, heart failure (HF) or MI hospitalization, and the separate endpoints death and HF hospitalization. IL-18 was the most important predictor of MI hospitalization. In a Cox regression, the highest tertile of IL-6 was associated with the composite endpoint (HR (95% CI) 1.91 (1.31-2.79)), death (2.38 (1.42-3.98)) and HF hospitalization (2.70 (1.32-5.50)), when adjusting for age, sex and CV risk factors. The highest tertile of IL-18 was associated with MI hospitalization (2.31 (1.08-4.91)) when severity of coronary atherosclerosis was added to the same type of model.

CONCLUSIONS

When nine inflammatory markers involved in atherosclerosis were analyzed three months after the acute event in young MI patients, IL-6 and IL-18 were the most important biomarkers to predict long-term CV outcomes during 20 years of follow-up.

Deregulation of MMP-2 and MMP-9 in laryngeal cancer: A retrospective observational study

Laryngeal carcinoma (LC) is reported to have a higher incidence rate among all types of head and neck cancers around the globe. Mechanisms resulting in the pathogenesis of LC are complicated due to involvement of invasion and metastasis and there is a need to understand this complicated multistep process. Numerous molecules including matrix metalloproteinases (MMPs) are involved in regulating metastatic mechanisms. Furthermore, activation and expression of different classes of MMPs have been observed in multiple pathological and physiological events including inflammation, invasion, and metastasis. Among all members of MMPs, matrix metalloproteinases-2 (MMP-2), and matrix metalloproteinases-9 (MMP-9) have been frequently reported to correlate with tumor pathogenesis. The present study is designed to check the involvement of MMP-2 and MMP-9 in LC pathogenesis. 184 laryngeal tumor samples along with adjacent uninvolved healthy sections were collected to check the expression deregulation of the above-mentioned gene in LC using real-time PCR and immunohistochemistry (IHC). Real-time PCR and IHC analyses showed the significant upregulation of MMP-2 (P < .0001) and MMP-9 (P < .0001) genes in laryngeal tumors compared to controls. Spearman correlation showed the positive correlation of expression deregulation of selected MMPs with advanced TNM stage [MMP-2, (P < .0001); MMP-9, P < .0001] and smoking status [MMP-2 (P < .0001); MMP-9 P < .0001] in laryngeal pathogenesis. Receiver operating curve (ROC) analysis showed the good diagnostic/prognostic value of said markers in laryngeal cancer patients. The present study showed that significant upregulation of selected MMPs was found associated with an increased risk of laryngeal cancer and can act as good diagnostic markers for the detection of said disease.

Effect of SARS-CoV-2 Infection and BNT162b2 Vaccination on the mRNA Expression of Genes Associated with Angiogenesis

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), discovered in December 2019 in Wuhan, China, caused the coronavirus disease 2019 (COVID-19). Due to the rate of spread of this virus, the World Health Organization, in March 2020, recognised COVID-19 as a worldwide pandemic. The disease is multisystemic with varying degrees of severity. Unfortunately, despite intensive research, the molecular changes caused by SARS-CoV-2 remain unclear. Mechanisms affected by the virus infection include endothelial dysfunction and angiogenesis. Similarly, the vaccines developed so far affect the process of angiogenesis, contributing to the development of undesirable effects on part of the cardiovascular system. The presented research aimed to investigate the impact of the SARS-CoV-2 infection and the Pfizer Comirnaty vaccine (BNT162b2) on the molecular aspect of angiogenesis. We found that convalescents vaccinated with one dose of BNT162b2 were characterised by higher MMP-7 (metalloproteinases 7) expression than non-vaccinated convalescents and healthy volunteers vaccinated with one dose of BNT162b2. Moreover, non-vaccinated convalescents showed increased mRNA expression of ADAMTS1 (ADAM metallopeptidase with thrombospondin type 1 motif 1) compared to healthy volunteers vaccinated with one dose of BNT162b2. In addition, we showed significant sex differences in the expression of MMP-7. In conclusion, the results of our study suggest a significant impact of SARS-CoV-2 infection and vaccination on the course of angiogenesis at the molecular level.

Adverse birth outcomes are associated with circulating matrix metalloproteinases among pregnant women in Puerto Rico

Matrix metalloproteinases (MMPs) are major extracellular matrix (ECM) remodeling proteinases and regulate uterine remodeling, which is a critical process for healthy pregnancies. The goal of this study was to investigate associations between maternal blood MMPs during pregnancy and birth outcomes among 898 pregnant women in the Puerto Rico PROTECT birth cohort. MMPs (MMP1, MMP2, and MMP9) were quantified using a customized Luminex assay in blood samples collected at two gestational study visits (around 18 and 26 weeks gestation). Linear and logistic regression models were used to regress continuous and binary birth outcomes, respectively, on MMPs at each study visit separately. Sensitivity analyses were conducted to test for effect modification by fetal sex on associations between MMPs and birth outcomes. We observed significant associations between MMP2 at visit 1 and newborn length that were in the opposite direction from the associations between MMP9 at visit 3 and newborn length. MMPs were associated with increased odds of preeclampsia and gestational diabetes mellitus, though case numbers were low. We also observed significant inverse associations with gestational age for MMP9 and MMP2 at visit 1 and visit 3, respectively, and these associations were observed only in mothers carrying male fetuses. Further, MMP2 was associated with heavier female fetuses, whereas MMP9 was associated with lighter female fetuses. We observed significant associations between birth outcomes and MMPs, and the majority of these associations differed by fetal sex. This study highlighted significant MMPs-birth outcomes associations that may provide a basis to explore the impact of MMPs on endometrium health and physiology.

New insights into the role of matrix metalloproteinase 3 (MMP3) in bone

The Matrix Metalloproteinases are important regulators of bone metabolism and can influence bone mass and bone remodeling. We investigate the role of Matrix Metalloproteinase 3 (MMP3) on bone in mice, by using Mmp3 knockout (Mmp3 KO) in the context of estrogen deficiency, and in human, by analyzing the association of promoter polymorphism with bone mineral density in postmenopausal women and with MMP3 expression. We presented evidence in this paper that Mmp3 KO significantly increases trabecular bone mass and trabecular number and does not affect cortical bone thickness. We also found that Mmp3 KO protects from the deleterious effects of ovariectomy on bone mineral density in mice by preventing deterioration of bone microarchitecture. The effect of Mmp3 KO does not involve bone formation parameters but instead acts by inhibition of bone resorption, leading to a reduced bone loss associated to ovariectomy. By studying a human cohort, we found that a polymorphism located in the promoter of the human MMP3 gene is associated with bone mineral density in postmenopausal women and found that MMP3 rs632478 promoter variants are associated with change in promoter activity in transfection experiments. In conclusion MMP3, although weakly expressed in bone cells, could be one of the important regulators of sex hormone action in bone and whose activity could be targeted for therapeutic applications such as in Osteoporosis.

Sex-Related Differences of Matrix Metalloproteinases (MMPs): New Perspectives for These Biomarkers in Cardiovascular and Neurological Diseases

It is now established that sex differences occur in clinical manifestation, disease progression, and prognosis for both cardiovascular (CVDs) and central nervous system (CNS) disorders. As such, a great deal of effort is now being put into understanding these differences and turning them into “advantages”: (a) for the discovery of new sex-specific biomarkers and (b) through a review of old biomarkers from the perspective of the “newly” discovered sex/gender medicine. This is also true for matrix metalloproteinases (MMPs), enzymes involved in extracellular matrix (ECM) remodelling, which play a role in both CVDs and CNS disorders. However, most of the studies conducted up to now relegated sex to a mere confounding variable used for statistical model correction rather than a determining factor that can influence MMP levels and, in turn, disease prognosis. Consistently, this approach causes a loss of information that might help clinicians in identifying novel patterns and improve the applicability of MMPs in clinical practice by providing sex-specific threshold values. In this scenario, the current review aims to gather the available knowledge on sex-related differences in MMPs levels in CVDs and CNS conditions, hoping to shed light on their use as sex-specific biomarkers of disease prognosis or progression.

Tissue, age, sex, and disease patterns of matrisome expression in GTEx transcriptome data

The extracellular matrix (ECM) has historically been explored through proteomic methods. Whether or not global transcriptomics can yield meaningful information on the human matrisome is unknown. Gene expression data from 17,382 samples across 52 tissues, were obtained from the Genotype-Tissue Expression (GTEx) project. Additional datasets were obtained from The Cancer Genome Atlas (TCGA) program and the Gene Expression Omnibus for comparisons. Gene expression levels generally matched proteome-derived matrisome expression patterns. Further, matrisome gene expression properly clustered tissue types, with some matrisome genes including SERPIN family members having tissue-restricted expression patterns. Deeper analyses revealed 382 gene transcripts varied by age and 315 varied by sex in at least one tissue, with expression correlating with digitally imaged histologic tissue features. A comparison of TCGA tumor, TCGA adjacent normal and GTEx normal tissues demonstrated robustness of the GTEx samples as a generalized matrix control, while also determining a common primary tumor matrisome. Additionally, GTEx tissues served as a useful non-diseased control in a separate study of idiopathic pulmonary fibrosis (IPF) matrix changes, while identifying 22 matrix genes upregulated in IPF. Altogether, these findings indicate that the transcriptome, in general, and GTEx in particular, has value in understanding the state of organ ECM.

Serum MMP-3 and its association with central arterial stiffness among young adults is moderated by smoking and BMI

Central arterial stiffness is an independent predictor of cardiovascular disease. It is characterized by a marked reduction in the elastin-collagen ratio of the arterial wall extracellular matrix (ECM), and is largely the result of degradation of various ECM components. Matrix metalloproteinase-3 (MMP-3) may contribute to central arterial stiffness via its involvement in ECM homeostasis and remodeling. This study examined the association between serum MMP-3 concentrations and central arterial stiffness and potential interactions of MMP-3 and traditional cardiovascular risk factors in a population of healthy young adults. A total of 206 participants (n = 109 females) aged 19-25 years were included in the current study. Central arterial stiffness was measured non-invasively as carotid-femoral pulse wave velocity (cfPWV) (m/s). MMP-3 concentrations (ng/ml) were measured using ELISA techniques. Regression analyses were used to examine the association between cfPWV and MMP-3, adjusting for age, sex, smoking status, body mass index (BMI), instantaneous mean arterial pressure (MAP) and heart rate, and serum C-reactive protein. Interactions between MMP-3 with smoking, BMI, sex, and MAP were analyzed in subsequent regression models. MMP-3 was an independent predictor of cfPWV (β = 0.187, p = 0.007), and significant interactions between MMP-3 and regular smoking (β = 0.291, p = 0.022), and MMP-3 and BMI (β = 0.210, p = 0.013) were observed. Higher serum MMP-3 concentrations were associated with a faster cfPWV and thus, greater central arterial stiffness. Interactions between MMP-3 and smoking, and MMP-3 and BMI may, in part, drive the association between MMP-3 and central arterial stiffness.

Profiles of histidine-rich glycoprotein associate with age and risk of all-cause mortality

Despite recognizing aging as a common risk factor of many human diseases, little is known about its molecular traits. To identify age-associated proteins circulating in human blood, we screened 156 individuals aged 50-92 using exploratory and multiplexed affinity proteomics assays. Profiling eight additional study sets (N = 3,987), performing antibody validation, and conducting a meta-analysis revealed a consistent age association (P = 6.61 × 10^-6) for circulating histidine-rich glycoprotein (HRG). Sequence variants of HRG influenced how the protein was recognized in the immunoassays. Indeed, only the HRG profiles affected by rs9898 were associated with age and predicted the risk of mortality (HR = 1.25 per SD; 95% CI = 1.12-1.39; P = 6.45 × 10^-5) during a follow-up period of 8.5 yr after blood sampling (IQR = 7.7-9.3 yr). Our affinity proteomics analysis found associations between the particular molecular traits of circulating HRG with age and all-cause mortality. The distinct profiles of this multipurpose protein could serve as an accessible and informative indicator of the physiological processes related to biological aging.

Matrix Metalloproteinases (MMP-2,-3,-9) Gene Polymorphisms in Cases of Benign Vocal Fold Lesions and Laryngeal Carcinoma

BACKGROUND/AIM

The matrix metalloproteinases (MMP) play an important role in the physiological and pathological remodeling of tissues including carcinogenesis. The study's aim was to assess the relations between MMP-2(-735C/T), MMP-2(-1306C/T), MMP-9(-1562C/T), and MMP-3(-11715A/6A) polymorphisms, and clinical/morphological manifestation of laryngeal squamous cell carcinoma (LSCC) and benign vocal fold lesions (BVFL).

PATIENTS AND METHODS

Two hundred and seventeen patients with LSCC and BVFL and 458 controls were included in this study. The genotyping was performed using the real-time polymerase chain reaction method.

RESULTS

The MMP-2(-1306C/T) C/T genotype was significantly rarer among the patients with moderate-poorly differentiated LSCC compared to the control group, however the MMP-3(-11715A/6A) 6A/6A genotype was significantly more frequent compared to controls. Smoking and 6A/6A genotype of MMP-3(-11715A/6A) polymorphism were associated with increased odds of LSCC risk. No associations between MMP genotypes and BVFL were found.

CONCLUSION

Smoking and MMP-3 (-11715A/6A) 6A/6A genotype may cause a higher risk for developing LSCC.

Angiopoietin-like protein 8 differentially regulates ANGPTL3 and ANGPTL4 during postprandial partitioning of fatty acids

Angiopoietin-like protein (ANGPTL)8 has been implicated in metabolic syndrome and reported to regulate adipose FA uptake through unknown mechanisms. Here, we studied how complex formation of ANGPTL8 with ANGPTL3 or ANGPTL4 varies with feeding to regulate LPL. In human serum, ANGPTL3/8 and ANGPTL4/8 complexes both increased postprandially, correlated negatively with HDL, and correlated positively with all other metabolic syndrome markers. ANGPTL3/8 also correlated positively with LDL-C and blocked LPL-facilitated hepatocyte VLDL-C uptake. LPL-inhibitory activity of ANGPTL3/8 was >100-fold more potent than that of ANGPTL3, and LPL-inhibitory activity of ANGPTL4/8 was >100-fold less potent than that of ANGPTL4. Quantitative analyses of inhibitory activities and competition experiments among the complexes suggested a model in which localized ANGPTL4/8 blocks the LPL-inhibitory activity of both circulating ANGPTL3/8 and localized ANGPTL4, allowing lipid sequestration into fat rather than muscle during the fed state. Supporting this model, insulin increased ANGPTL3/8 secretion from hepatocytes and ANGPTL4/8 secretion from adipocytes. These results suggest that low ANGPTL8 levels during fasting enable ANGPTL4-mediated LPL inhibition in fat tissue to minimize adipose FA uptake. During feeding, increased ANGPTL8 increases ANGPTL3 inhibition of LPL in muscle via circulating ANGPTL3/8, while decreasing ANGPTL4 inhibition of LPL in adipose tissue through localized ANGPTL4/8, thereby increasing FA uptake into adipose tissue. Excessive caloric intake may shift this system toward the latter conditions, possibly predisposing to metabolic syndrome.

Expression of Nik-related kinase in smooth muscle cells attenuates vascular inflammation and intimal hyperplasia

Inflammation of the vascular microenvironment modulates distinct types of vascular cells, and plays important roles in promoting atherosclerosis, stenosis/restenosis, and vascular-related diseases. Nik-related kinase (Nrk), a member of the Ste20-type kinase family, has been reported to be selectively expressed in embryonic skeletal muscle. However, whether Nrk is expressed in adult vascular smooth muscle, and if it influences intimal hyperplasia is unclear. Here, we found that Nrk is abundantly expressed in cultured vascular smooth muscle cells (VSMC) and mouse arterial intima. Treatment of mouse VSMCs with lipopolysaccharide (LPS) or platelet-derived growth factor significantly reduced Nrk expression. In addition, expression of Nrk was significantly reduced in regions of neointimal formation caused by guide-wire carotid artery injuries in mice, as well as in human atherosclerotic tissues, when compared to normal vessels. We identified that expression of matrix metalloproteinases (MMP3, MMP8 and MMP12) and inflammatory cytokines/chemokines (CCL6, CCL8, CCL11, CXCL1, CXCL3, CXCL5 and CXCL9) are synergistically induced by Nrk siRNA in LPS-treated mouse VSMCs. Moreover, we found that resveratrol significantly impaired LPS- and Nrk siRNA-induced expression of MMP3, CCL8, CCL11, CXCL3 and CXCL5. These results suggested that Nrk may play important roles in regulating pathological progression of atherosclerosis or neointimal- hyperplasia-related vascular diseases.

Genetic variation in CADM2 as a link between psychological traits and obesity

CADM2 has been associated with a range of behavioural and metabolic traits, including physical activity, risk-taking, educational attainment, alcohol and cannabis use and obesity. Here, we set out to determine whether CADM2 contributes to mechanisms shared between mental and physical health disorders. We assessed genetic variants in the CADM2 locus for association with phenotypes in the UK Biobank, IMPROVE, PROCARDIS and SCARFSHEEP studies, before performing meta-analyses. A wide range of metabolic phenotypes were meta-analysed. Psychological phenotypes analysed in UK Biobank only were major depressive disorder, generalised anxiety disorder, bipolar disorder, neuroticism, mood instability and risk-taking behaviour. In UK Biobank, four, 88 and 172 genetic variants were significantly (p < 1 × 10⁻⁵) associated with neuroticism, mood instability and risk-taking respectively. In meta-analyses of 4 cohorts, we identified 362, 63 and 11 genetic variants significantly (p < 1 × 10⁻⁵) associated with BMI, SBP and CRP respectively. Genetic effects on BMI, CRP and risk-taking were all positively correlated, and were consistently inversely correlated with genetic effects on SBP, mood instability and neuroticism. Conditional analyses suggested an overlap in the signals for physical and psychological traits. Many significant variants had genotype-specific effects on CADM2 expression levels in adult brain and adipose tissues. CADM2 variants influence a wide range of both psychological and metabolic traits, suggesting common biological mechanisms across phenotypes via regulation of CADM2 expression levels in adipose tissue. Functional studies of CADM2 are required to fully understand mechanisms connecting mental and physical health conditions.

Soluble EMMPRIN levels discriminate aortic ectasia in Marfan syndrome patients

Marfan syndrome (MFS) is a rare genetic disease characterized by a matrix metalloproteases (MMPs) dysregulation that leads to extracellular matrix degradation. Consequently, MFS patients are prone to develop progressive thoracic aortic enlargement and detrimental aneurysm. Since MMPs are activated by the extracellular MMP inducer (EMMPRIN) protein, we determined whether its plasmatic soluble form (sEMMPRIN) may be considered a marker of thoracic aortic ectasia (AE). Methods: We compared plasma sEMMPRIN levels of 42 adult Caucasian MFS patients not previously subjected to aortic surgery with those of matched healthy controls (HC) by ELISA. In the MFS cohort we prospectively evaluated the relationship between plasma sEMMPRIN levels and the main MFS-related manifestations. Results: MFS patients had lower plasma sEMMPRIN levels (mean±SD: 2071±637 pg/ml) than HC (2441±642 pg/ml, p=0.009). Amongst all considered MFS-related clinical features, we found that only aortic root dilatation associated with circulating sEMMPRIN levels. Specifically, plasma sEMMPRIN levels negatively correlated with aortic Z-score (r=-0.431, p=0.004), and were significantly lower in patients with AE (Z-score≥2, 1788±510 pg/ml) compared to those without AE (Z-score<2, 2355±634 pg/ml; p=0.003). ROC curve analysis revealed that plasma sEMMPRIN levels discriminated patients with AE (AUC [95%CI]: 0.763 [0.610-0.916], p=0.003) with 85.7% sensitivity, 76.2% specificity, and 81% accuracy. We defined plasma sEMMPRIN levels ≤2246 pg/ml as the best threshold discriminating the presence of AE in MFS patients with an odds ratio [95%CI] of 19.2 [3.947-93.389] (p<0.001). Conclusions: MFS patients are characterized by lower sEMMPRIN levels than HC. Notably, plasma sEMMPRIN levels are strongly associated with thoracic AE.

Correlations of MMP-1, MMP-3, and MMP-12 with the degree of atherosclerosis, plaque stability and cardiovascular and cerebrovascular events

We analyzed the effects of matrix metalloproteinase (MMP)-1, MMP-3, and MMP-12 on the degree of carotid atherosclerosis (CAS) and plaque stability, and investigated their correlations with cardiovascular and cerebrovascular events (CCEs). Two hundred CAS patients were enrolled. Carotid intima-media thickness (IMT) was measured using ultrasonic examination. Patients were divided into the no plaque group (NP group), stable plaque group (SP group), and vulnerable plaque group (VP group). The Crouse method was used for the evaluation of plaque scores. Additionally, 60 healthy subjects were enrolled as the control group. Serum triacylglycerol (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were analyzed. The serum protein levels of MMP-1, MMP-3, and MMP-12 were measured by western blotting. The frequency of CCEs within 2 years was recorded, and its correlation with MMP-1, MMP-3, and MMP-12 was analyzed. The CAS plaque scores in the SP and VP groups were significantly increased compared with the NP group, and the difference between the SP and VP groups was significant. The levels of TC, TG, LDL-C, and HDL-C of CAS patients were significantly increased compared with those in the control group, but the differences in these indexes between the patient groups were not significant. Western blotting showed that the levels of MMP-1, MMP-3, and MMP-12 in the patient groups were significantly increased compared with those in the control group, and the protein levels in the VP group were significantly higher than those in the SP and NP groups. Additionally, the levels of MMP-1, MMP-3, and MMP-12 had significantly positive correlations with the occurrence of CCEs in CAS patients. In conclusion, MMP-1, MMP-3, and MMP-12 are positively correlated with CCEs in CAS patients. They can be used as markers for the clinical diagnosis and prognosis of CAS.

Chronic inhalation of e-cigarette vapor containing nicotine disrupts airway barrier function and induces systemic inflammation and multiorgan fibrosis in mice

Electronic (e)-cigarettes theoretically may be safer than conventional tobacco. However, our prior studies demonstrated direct adverse effects of e-cigarette vapor (EV) on airway cells, including decreased viability and function. We hypothesize that repetitive, chronic inhalation of EV will diminish airway barrier function, leading to inflammatory protein release into circulation, creating a systemic inflammatory state, ultimately leading to distant organ injury and dysfunction. C57BL/6 and CD-1 mice underwent nose only EV exposure daily for 3-6 mo, followed by cardiorenal physiological testing. Primary human bronchial epithelial cells were grown at an air-liquid interface and exposed to EV for 15 min daily for 3-5 days before functional testing. Daily inhalation of EV increased circulating proinflammatory and profibrotic proteins in both C57BL/6 and CD-1 mice: the greatest increases observed were in angiopoietin-1 (31-fold) and EGF (25-fold). Proinflammatory responses were recapitulated by daily EV exposures in vitro of human airway epithelium, with EV epithelium secreting higher IL-8 in response to infection (227 vs. 37 pg/ml, respectively; P < 0.05). Chronic EV inhalation in vivo reduced renal filtration by 20% ( P = 0.017). Fibrosis, assessed by Masson's trichrome and Picrosirius red staining, was increased in EV kidneys (1.86-fold, C57BL/6; 3.2-fold, CD-1; P < 0.05), heart (2.75-fold, C57BL/6 mice; P < 0.05), and liver (1.77-fold in CD-1; P < 0.0001). Gene expression changes demonstrated profibrotic pathway activation. EV inhalation altered cardiovascular function, with decreased heart rate ( P < 0.01), and elevated blood pressure ( P = 0.016). These data demonstrate that chronic inhalation of EV may lead to increased inflammation, organ damage, and cardiorenal and hepatic disease.

Substrate stiffness regulated migration and angiogenesis potential of A549 cells and HUVECs

Tumor tissue tends to stiffen during solid tumor progression. Substrate stiffness is known to alter cell behaviors, such as proliferation and migration, during which angiogenesis is requisite. Mono- and co-culture systems of lung cancer cell line A549 and human umbilical vein endothelial cells (HUVECs), on polydimethylsiloxane substrates (PDMS) with varying stiffness, were used for investigating the effects of substrate stiffness on the migration and angiogenesis of lung cancer. The expressions of matrix metalloproteinases (MMPs) and angiogenesis-related growth factors were up-regulated with the increase of substrate stiffness, whereas that of tissue inhibitor of matrix metalloproteinase (TIMPs) were down-regulated with increasing substrate stiffness. Our data not only suggested that stiff substrate may promote the migration and angiogenesis capacities of lung cancer, but also suggested that therapeutically targeting lung tumor stiffness or response of ECs to lung tumor stiffness may help reduce migration and angiogenesis of lung tumor.

Fast and general tests of genetic interaction for genome-wide association studies

A complex disease has, by definition, multiple genetic causes. In theory, these causes could be identified individually, but their identification will likely benefit from informed use of anticipated interactions between causes. In addition, characterizing and understanding interactions must be considered key to revealing the etiology of any complex disease. Large-scale collaborative efforts are now paving the way for comprehensive studies of interaction. As a consequence, there is a need for methods with a computational efficiency sufficient for modern data sets as well as for improvements of statistical accuracy and power. Another issue is that, currently, the relation between different methods for interaction inference is in many cases not transparent, complicating the comparison and interpretation of results between different interaction studies. In this paper we present computationally efficient tests of interaction for the complete family of generalized linear models (GLMs). The tests can be applied for inference of single or multiple interaction parameters, but we show, by simulation, that jointly testing the full set of interaction parameters yields superior power and control of false positive rate. Based on these tests we also describe how to combine results from multiple independent studies of interaction in a meta-analysis. We investigate the impact of several assumptions commonly made when modeling interactions. We also show that, across the important class of models with a full set of interaction parameters, jointly testing the interaction parameters yields identical results. Further, we apply our method to genetic data for cardiovascular disease. This allowed us to identify a putative interaction involved in Lp(a) plasma levels between two ‘tag’ variants in the LPA locus (p = 2.42 ⋅ 10⁻⁰⁹) as well as replicate the interaction (p = 6.97 ⋅ 10⁻⁰⁷). Finally, our meta-analysis method is used in a small (N = 16,181) study of interactions in myocardial infarction.

Interaction between organic molecules forms the basis of all biological systems. The availability of high-throughput genotyping and sequencing platforms enables us to cost-effectively genotype a large number of individuals. For sufficiently large datasets it is possible to reconstruct the genetic dependencies that underlie complex traits and diseases. However, there is a need for efficient statistical methodologies that can tackle the large sample size and computational resources required to study interaction. In this work we provide theory that reduces the required computational resources, and enable multiple research groups to effectively combine their results.

The T Allele of rs8075977 in the 5'-Flanking Region of the PEDF Gene Is Associated with Reduced Risk of Coronary Artery Disease in Elderly Chinese Men

Coronary artery disease (CAD) is a multifactorial disease with a genetic component. Pigment epithelium-derived factor (PEDF) exerts anti-inflammatory, anti-oxidant, anti-thrombotic, and anti-angiogenic effects and thus has received increasing attention as a sensitive biomarker of atherosclerosis and CAD. To explore the potential association between PEDF single nucleotide polymorphisms (SNPs) and CAD, we performed this case-control study of consecutive elderly Chinese Han male patients (n = 416) and age-matched male controls (n = 528) without a history of CAD or electrocardiographic signs of CAD. The enrolled CAD patients (age ≥ 60 years) are not biologically related. A tag approach was used to examine 100% of common variations in the PEDF gene (r² ≥ 0.8, minor allele frequency > 0.1). PEDF tag SNPs (tSNPs) were selected using the HapMap Data-CHB which describes the common patterns of human DNA sequence variation and Tagger program. SNPs were genotyped using ligase detection reaction (LDR). Seven tSNPs (rs8075977, rs11658342, rs1136287, rs12603825, rs12453107, rs6828 and rs11078634) were selected. Among them, only one SNP, rs8075977 (C/T) located in the 5'-flanking region, showed the significant effect on the susceptibility to CAD. The frequency of its T allele was significantly higher in the controls (52.7%) than that in the CAD group (46.2%) (adjusted OR = 0.88, 95% CI: 0.80-0.96; P = 0.005). In conclusion, the T allele of rs8075977 in the 5'-flanking region of the PEDF gene may be protective for CAD. Conversely, the C allele at this variation site is associated with CAD in elderly Chinese Han men.

Genetic Influences on the Development of Fibrosis in Crohn's Disease

Fibrostenotic strictures are an important complication in patients with Crohn’s disease (CD), very often necessitating surgery. This fibrotic process develops in a genetically susceptible individual and is influenced by an interplay with environmental, immunological, and disease-related factors. A deeper understanding of the genetic factors driving this fibrostenotic process might help to unravel the pathogenesis, and ultimately lead to development of new, anti-fibrotic therapy. Here, we review the genetic factors that have been associated with the development of fibrosis in patients with CD, as well as their potential pathophysiological mechanism(s). We also hypothesize on clinical implications, if any, and future research directions.

NLRP3 Inflammasome Expression and Activation in Human Atherosclerosis

Background

The NLR family, pyrin domain containing 3 (NLRP3) inflammasome is an interleukin (IL)‐1β and IL‐18 cytokine processing complex that is activated in inflammatory conditions. The role of the NLRP3 inflammasome in the pathogenesis of atherosclerosis and myocardial infarction is not fully understood.

Methods and Results

Atherosclerotic plaques were analyzed for transcripts of the NLRP3 inflammasome, and for IL‐1β release. The Swedish First‐ever myocardial Infarction study in Ac‐county (FIA) cohort consisting of DNA from 555 myocardial infarction patients and 1016 healthy individuals was used to determine the frequency of 4 single nucleotide polymorphisms (SNPs) from the downstream regulatory region of NLRP3. Expression of NLRP3, Apoptosis‐associated speck‐like protein containing a CARD (ASC), caspase‐1 (CASP1), IL1B, and IL18 mRNA was significantly increased in atherosclerotic plaques compared to normal arteries. The expression of NLRP3 mRNA was significantly higher in plaques of symptomatic patients when compared to asymptomatic ones. CD68‐positive macrophages were observed in the same areas of atherosclerotic lesions as NLRP3 and ASC expression. Occasionally, expression of NLRP3 and ASC was also present in smooth muscle cells. Cholesterol crystals and ATP induced IL‐1β release from lipopolysaccharide‐primed human atherosclerotic lesion plaques. The minor alleles of the variants rs4266924, rs6672995, and rs10733113 were associated with NLRP3 mRNA levels in peripheral blood mononuclear cells but not with the risk of myocardial infarction.

Conclusions

Our results indicate a possible role of the NLRP3 inflammasome and its genetic variants in the pathogenesis of atherosclerosis.

Matrix Metalloproteinase 3 Gene Polymorphism and Its Level Predict Morbidity After Acute Myocardial Infarction

OBJECTIVES

Matrix metalloproteinase is responsible for ventricular remodeling after acute myocardial infarction (MI). The purpose of the present study was to determine whether the matrix metalloproteinase 3 (MMP-3) polymorphism and its level predict morbidity after acute MI (AMI).

METHODS

We studied 112 patients with AMI and 140 controls. All patients were followed for AMI complications during their hospitalization and 6 months after. Serum MMP-3 was measured. MMP-3-1612 5A/6A polymorphism was genotyped by polymerase chain reaction.

RESULTS

We observed that the serum MMP-3 levels were significantly increased in patients with AMI with morbidity compared with patients without complications. Also, MMP-3 levels in patients with AMI carrying 5A/5A were elevated compared with those carrying 6A/6A. The frequencies of 5A/5A genotypes were significantly increased in patients with AMI compared with controls, and patients with AMI carrying 5A/5A had a fivefold increased risk of developing morbidity. The impairment of left ventricular function (ΔFS [fractional shortening] and ΔEF [ejection fraction]) was observed more in the 5A/5A genotype compared with the 6A/6A genotype. A significant inverse correlation between predischarge MMP-3 levels and FS and EF was found at 6 months follow-up.

CONCLUSIONS

MMP-3 polymorphism has a significant association with the risk of developing morbidity after AMI. Higher predischarge MMP-3 levels are associated with left ventricular dysfunction after AMI.

The effect of gender and genetic polymorphisms on matrix metalloprotease (MMP) and tissue inhibitor (TIMP) plasma levels in different infectious and non-infectious conditions

Matrix metalloproteases (MMPs) are increased in different infections due to their role in controlling immune responses and are regulated by tissue inhibitors (TIMPs). Different MMP promoter single nucleotide polymorphisms (SNPs) induce changes in MMP genes, mRNA and protein expression. Gender might also modify MMP plasma levels. In order to determine the weight of these variables on MMP secretion we studied MMP-1, -2, -3, -8, -9, -10, -13 and TIMP-1, -2, -4 plasma levels in 90 patients with severe bacterial sepsis, 102 with anti-retroviral (ARV)-treated HIV monoinfection, 111 with ARV-treated HIV-hepatitis C virus (HCV) co-infection and 86 non-infected controls (45 stroke and 41 trauma patients). MMP-1(-1607 1G/2G), MMP-3(-1612 5A/6A), MMP-8(-799C/T), MMP-9(-1562 C/T) and MMP-13(-77A/G) SNPs were genotyped. MMP-3 plasma levels were significantly higher in men than in women in each diagnostic group, and MMP-3 SNP allele 6A carriers also had higher levels than allele 5A carriers, an effect that was magnified by sepsis. Independent predictors of higher MMP-3 levels were male gender (P = 0.0001), MMP-3(-1612 5A/6A) SNP (P = 0.001), higher levels of TIMP-4 (P = 0.004) and MMP-8 (P = 0.006) and lower levels of MMP-1 (P = 0.03) by multivariate analysis. No strong associations with gender or SNPs were observed for other MMPs or TIMPs. In conclusion, male gender and MMP-3(-1612 5A/6A) 6A allele carriage increased MMP-3 plasma levels significantly, especially in patients with severe bacterial sepsis. This confounding gender effect needs to be addressed when evaluating MMP-3 plasma levels in any infectious or non-infectious condition.

Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF

Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] ≥0.01 and <0.05) and rare (MAF <0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76,000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n = 2) and rare (n = 10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways.

Duffy antigen receptor genetic variant and the association with Interleukin 8 levels

The aim of this study is to identify loci associated with circulating levels of Interleukin 8 (IL8). We investigated the associations of 121,445 single nucleotide polymorphisms (SNPs) from the Illumina 200K CardioMetabochip with IL8 levels in 1077 controls from the Stockholm Heart Epidemiology Program (SHEEP) study, using linear regression under an additive model of inheritance. Five SNPs (rs12075A/G, rs13179413C/T, rs6907989T/A, rs9352745A/C, rs1779553T/C) reached the pre-defined threshold of genome-wide significance (p<1.0×10(-5)) and were tested for in silico replication in three independent populations, derived from the PIVUS, MDC-CC and SCARF studies. IL8 was measured in serum (SHEEP, PIVUS) and plasma (MDC-CC, SCARF). The strongest association was found with the SNP rs12075 A/G, Asp42Gly (p=1.6×10(-6)), mapping to the Duffy antigen receptor for chemokines (DARC) gene on chromosome 1. The minor allele G was associated with 15.6% and 10.4% reduction in serum IL8 per copy of the allele in SHEEP and PIVUS studies respectively. No association was observed between rs12075 and plasma IL8.

CONCLUSION

rs12075 was associated with serum levels but not with plasma levels of IL8. It is likely that serum IL8 represents the combination of levels of circulating plasma IL8 and additional chemokine liberated from the erythrocyte DARC reservoir due to clotting. These findings highlight the importance of understanding IL8 as a biomarker in cardiometabolic diseases.

Autoantibodies against basement membrane collagen type IV are associated with myocardial infarction

Background

Collagen type IV is the major constituent of basement membranes underlying endothelial cells and is important for endothelial cell attachment and function. Autoantibodies against native collagen type IV have been found in various autoimmune diseases. Oxidation of LDL in the vascular wall results in the formation of reactive aldehydes, which could modify surrounding matrix proteins. Like oxidized LDL, these modified matrix proteins are likely to induce immune responses. We examined whether autoantibodies against native or aldehyde-modified collagen type IV are associated with myocardial infarction.

Methods

IgM and IgG against native and aldehyde-modified collagen type IV were measured by ELISA in serum from 387 survivors of a first myocardial infarction and 387 age- and sex-matched controls.

Results

Post-infarction patients had significantly increased levels of IgM against native collagen type IV, and IgG against native collagen type IV was present at detectable level in 17% of patients as opposed to 7% of controls (p < 0.001). Controlling for major cardiovascular risk factors demonstrated that the presence of IgG against native collagen type IV was associated with myocardial infarction (OR 2.9 (1.6–5.4), p = 0.001). Similarly, subjects in the highest quartile of IgM against native collagen type IV had increased risk of having suffered myocardial infarction (OR 3.11 (1.8–5.4), p < 0.001) after adjusting for cardiovascular risk factors. In contrast, IgG against aldehyde-modified collagen type IV was decreased in myocardial infarction patients, but this association was not independent of established cardiovascular risk factors.

Conclusion

Autoantibodies against collagen type IV are associated with myocardial infarction independently of traditional cardiovascular risk factors.

•

We measured native and MDA-collagen type IV IgM and IgG in MI patients and controls.

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Post-infarction patients had increased levels of IgM against native collagen type IV.

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Presence of IgG against native collagen type IV was associated with MI.

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In contrast, IgG against MDA-collagen type IV was decreased in MI patients.

Lim domain binding 2: a key driver of transendothelial migration of leukocytes and atherosclerosis

OBJECTIVE

Using a multi-tissue, genome-wide gene expression approach, we recently identified a gene module linked to the extent of human atherosclerosis. This atherosclerosis module was enriched with inherited risk for coronary and carotid artery disease (CAD) and overlapped with genes in the transendothelial migration of leukocyte (TEML) pathway. Among the atherosclerosis module genes, the transcription cofactor Lim domain binding 2 (LDB2) was the most connected in a CAD vascular wall regulatory gene network. Here, we used human genomics and atherosclerosis-prone mice to evaluate the possible role of LDB2 in TEML and atherosclerosis.

APPROACH AND RESULTS

mRNA profiles generated from blood macrophages in patients with CAD were used to infer transcription factor regulatory gene networks; Ldlr(-/-)Apob(100/100) mice were used to study the effects of Ldb2 deficiency on TEML activity and atherogenesis. LDB2 was the most connected gene in a transcription factor regulatory network inferred from TEML and atherosclerosis module genes in CAD macrophages. In Ldlr(-/-)Apob(100/100) mice, loss of Ldb2 increased atherosclerotic lesion size ≈2-fold and decreased plaque stability. The exacerbated atherosclerosis was caused by increased TEML activity, as demonstrated in air-pouch and retinal vasculature models in vivo, by ex vivo perfusion of primary leukocytes, and by leukocyte migration in vitro. In THP1 cells, migration was increased by overexpression and decreased by small interfering RNA inhibition of LDB2. A functional LDB2 variant (rs10939673) was associated with the risk and extent of CAD across several cohorts.

CONCLUSIONS

As a key driver of the TEML pathway in CAD macrophages, LDB2 is a novel candidate to target CAD by inhibiting the overall activity of TEML.

Role of plasma matrix-metalloproteases (MMPs) and their polymorphisms (SNPs) in sepsis development and outcome in ICU patients

Matrix-metalloproteases (MMPs) and their tissue-inhibitors (TIMPs), modulated by different single nucleotide polymorphisms (SNPs), are critical in sepsis development. Ninety ICU severely septic and 91 ICU uninfected patients were prospectively studied. MMP-1 (−1607 1G/2G), MMP-3 (−1612 5A/6A), MMP-8 (−799 C/T), MMP-9 (−1562 C/T), and MMP-13 (−77A/G) SNPs were genotyped. Plasma MMPs (-1, -2, -3, -8, -9, -10, -13) and TIMPs (-1,-2,-4) were measured. AA homozygotes and A allele carriers of MMP-13 (−77 A/G) and 1G2G carriers of the MMP-1 (−1607 1G/2G) SNPs frequencies were different between septic and uninfected patients (p < 0.05), as well as plasma MMP-3, -8, -9 -10 and TIMP-2 levels (p < 0.04). No differences in MMPs levels among MMP-13 or MMP-1 SNPs genotypes carriers were observed. The area under the ROC curve for MMP-8 in the diagnosis of sepsis was 0.87 (95% CI 0.82–0.92), and that of CRP was 0.98 (0.94–0.998), whereas the area of MMP-9 in the detection of non-septic state was 0.73 (0.65–0.80), p < 0.0001 for all curves. Sepsis associated with increased MMP-8 and decreased MMP-9 levels in multivariate analysis (p < 0.0002). We report for the first time an association between MMP-13 and MMP-1 SNPs and sepsis. An independent association of MMP-8 and MMP-9 levels with sepsis was also observed.

The Role of Matrix Metalloproteinases Polymorphisms in Age-Related Macular Degeneration

BACKGROUND

Matrix metalloproteinases (MMP) are responsible for the degradation of extracellular matrix components and play an important role in the physiological and pathological remodeling of tissues.

PURPOSE

To assess the impact of MMP-2 Rs2285053 (C->T), MMP-3 Rs3025039 (5A->6A), and MMP-9 Rs3918242 (C->T) single nucleotide polymorphism on the development of early age-related macular degeneration (AMD).

METHODS

The study group comprised 148 patients with AMD, and the control group enrolled 526 randomly selected persons. The genotyping of MMP-3 Rs3025039, MMP-2 Rs2285053, and MMP-9 Rs3918242 was performed by using the real-time PCR method.

RESULTS

The frequency of the MMP-2 (-735) C/T and MMP-3 (-1171) 5A/6A genotypes did not differ significantly between the patients with AMD and the control group, while the MMP-9 (-1562) C/C genotype was more frequently detected in patients with AMD than the control group (73.7% vs. 64.6%, p=0.048). Logistic regression analysis showed that the MMP-9 (-1562) C/C genotype increased the likelihood of developing early AMD (OR=1.51, 95% CI: 1.01-2.21; p=0.046). After the subdivision into the groups by age, a significant difference only in the frequency of the MMP-9 (-1562) C/C genotype was found comparing the AMD patients and the control group younger than 65 years (79.7% vs. 66.4%, p=0.039).

CONCLUSIONS

Only MMP-9 Rs3918242 (C->T) single nucleotide polymorphism was found to play a significant role in the development of AMD, and the effect was more pronounced at the age of less than 65 years.

CARD8 gene encoding a protein of innate immunity is expressed in human atherosclerosis and associated with markers of inflammation

Inflammation is a key factor in the development of atherosclerotic coronary artery disease. It is promoted through the inflammasome, a molecular machine that produces IL (interleukin)-1β in response to cholesterol crystal accumulation in macrophages. The CARD8 (caspase recruitment domain 8) protein modulates this process by suppressing caspase 1 and the transcription factor NF-κB (nuclear factor κB). The expression of CARD8 mRNA was examined in atherosclerotic vascular tissue and the impact on MI (myocardial infarction) of a polymorphism in the CARD8 gene determined. CARD8 mRNA was analysed by microarray of human atherosclerotic tissue and compared with transplant donor arterial tissue. Microarray analysis was performed for proximal genes associated with the rs2043211 locus in plaque. The CARD8 rs2043211 polymorphism was analysed by genotyping of two Swedish MI cohorts, FIA (First Myocardial Infarction in Northern Sweden) and SCARF (Stockholm Coronary Atherosclerosis Risk Factor). The CRP (C-reactive protein) level was measured in both cohorts, but the levels of the pro-inflammatory cytokines IL-1β, IL-18, TNF (tumour necrosis factor) and MCP-1 (monocyte chemoattractant protein) were measured in sera available from the SCARF cohort. CARD8 mRNA was highly expressed in atherosclerotic plaques compared with the expression in transplant donor vessel (P<0.00001). The minor allele was associated with lower expression of CARD8 in the plaques, suggesting that CARD8 may promote inflammation. Carriers of the minor allele of the rs2043211 polymorphism also displayed lower circulating CRP and lower levels of the pro-atherosclerotic chemokine MCP-1. However, no significant association could be detected between this polymorphism and MI in the two cohorts. Genetic alterations in the CARD8 gene therefore seem to be of limited importance for the development of MI.

Auto-antibodies as emergent prognostic markers and possible mediators of ischemic cardiovascular diseases

During the last 15 years, a growing body of evidence supported the fact that auto-antibodies represent not only emergent markers but also active mediators of cardiovascular disease (CVD), clinically represented mostly by acute coronary syndrome (ACS) and stroke. There is a contrasted relationship between auto-antibodies and CVD, some being protective, while others acting as potential risk factors. Therefore, we performed a review of the literature on the respective cardiovascular prognostic value of the most relevant auto-antibodies in ACS and stroke, and their putative pathophysiological properties in atherogenesis. This review highlights auto-antibodies as active modulators of the innate immune system in atherogenesis (either toward a pro- or anti-inflammatory response), or by affecting basal heart rate regulation (anti-apoA-1 IgG). Given their apparent prognostic independency towards traditional cardiovascular risk factors, the data available in the literature indicates that some of those auto-antibodies could be of valuable help for cardiovascular risk stratification in the future, especially because their deleterious effects have been shown to be potentially abrogated in vivo and in vitro by existing therapeutic modalities. Although evidence in humans is currently lacking, these studies may open innovative therapeutic perspectives for CVD in the future.

Association of circulating levels of MMP-8 with mortality from respiratory disease in patients with rheumatoid arthritis

Introduction

Matrix metalloproteinases (MMPs) are implicated in the destruction of the joint and have been shown to be strongly associated with inflammation in rheumatoid arthritis (RA). Circulating MMPs have also been associated with cardiovascular disease in the general population, and are predictive of cardiovascular mortality. The purpose of the present study was to determine whether circulating levels of MMPs are predictive of mortality in RA.

Methods

A multiplex suspension array system (Luminex^®) was used to measure levels of MMPs (1, 2, 3, 8 and 9) in sera taken at recruitment of RA patients (n = 487) in a study of factors associated with mortality in RA. Patients were tracked on the National Health Service Central Register for notification of death, and the relationship between baseline MMP levels and mortality was analysed using Cox proportional hazards regression analysis.

Results

At the time of follow-up, 204/486 patients had died, of which 94 (46.1%) had died of circulatory diseases, 49 of malignancy (24.0%), and 42 (20.6%) of respiratory diseases. In a stepwise analysis which included all MMPs, only MMP-8 was significantly associated with all cause mortality (P = 0.0007, 0.6% hazard ratio increase per ng/ml). No association was found between MMP levels and mortality due to circulatory disease or malignancy. However MMP-8 levels were strongly associated with mortality due to respiratory disease (P < 0.0001, 1.3% hazard ratio increase per ng/ml). The association with respiratory disease related mortality remained highly significant in multivariate models which included smoking as well as markers of severity and disease activity such as rheumatoid factor, nodular disease, and C-reactive protein (CRP).

Conclusions

The serum level of MMP-8 is a strong predictor of mortality in RA, especially that due to respiratory disease. This finding is consistent with increased activation of neutrophils in RA and identifies serum MMP-8 as a useful marker for increased risk of premature death.

A CYP26B1 polymorphism enhances retinoic acid catabolism and may aggravate atherosclerosis

All-trans retinoic acid, controlled by cytochrome P450, family 26 (CYP26) enzymes, potentially has beneficial effects in atherosclerosis treatment. This study investigates CYP26 subfamily B, polypeptide 1 (CYP26B1) in atherosclerosis and the effects of a genetic polymorphism in CYP26B1 on retinoid catabolism. We found that CYP26B1 mRNA was induced by retinoic acid in human atherosclerotic arteries, and CYP26B1 and the macrophage marker CD68 were colocalized in human atherosclerotic lesions. In mice, Cyp26B1 mRNA was higher in atherosclerotic arteries than in normal arteries. Databases were queried for nonsynonymous CYP26B1 single nucleotide polymorphisms (SNPs) and rs2241057 selected for further studies. Constructs of the CYP26B1 variants were created and used for production of purified proteins and transfection of macrophagelike cells. The minor variant catabolized retinoic acid with significantly higher efficiency, indicating that rs2241057 is functional and suggesting reduced retinoid availability in tissues with the minor variant. rs2241057 was investigated in a Stockholm Coronary Atherosclerosis Risk Factor (SCARF) subgroup. The minor allele was associated with slightly larger lesions, as determined by angiography. In summary, this study identifies the first CYP26B1 polymorphism that alters CYP26B1 capacity to metabolize retinoic acid. CYP26B1 was expressed in macrophage-rich areas of human atherosclerotic lesions, induced by retinoic acid and increased in murine atherosclerosis. Taken together, the results indicate that CYP26B1 capacity is genetically regulated and suggest that local CYP26B1 activity may influence atherosclerosis.

NAMPT (visfatin) and AKT1 genetic variants associate with myocardial infarction

BACKGROUND

High plasma levels of the adipokine NAMPT (or visfatin) have been associated with cardiovascular disease. However experimental data suggest that NAMPT, via Akt signaling, protects the myocardium against hypoxic insults. We studied whether the NAMPT rs1319501, AKT1 rs3730358, p53 rs1042522, Mdm2 rs2279744 or eNOS rs1799983 SNP:s linked to NAMPT and Akt signaling associate with risk of myocardial infarction (MI).

METHODS

Cases were 828 men and 346 women aged 45-70 who had suffered a first MI. Control individuals, 1062 men and 513 women, were randomly chosen from the study base. We employed unconditional logistic regression analysis.

RESULTS

The rs1319501 minor allele associated with MI among women aged 45-60; odds ratio (OR) under a recessive model of inheritance: 2.96 (95% confidence interval [CI] 1.06-8.29). Replication analysis in an independent material yielded OR point estimates in the same direction. The rs3730358 minor allele associated with low MI risk in men aged 45-60 (OR dominant model: 0.72, 95% CI 0.53-0.97), an association completely attenuated by adjusting for inflammatory markers.

CONCLUSIONS

The NAMPT rs1319501 minor allele associates with increased MI risk in young women. In young men a protective effect of the AKT1 rs3730358 minor allele was suggested, possibly related to an attenuated inflammation.

Genetic polymorphism of MMP family and coronary disease susceptibility: a meta-analysis

The issue that genetic polymorphism of matrix metalloproteinase (MMP) family is in association with coronary disease is controversial. So we did a meta-analysis to clarify it clearly. We made a literature search of PubMed, the Web of Science, and Cochrane Collaboration's database to identify eligible reports. The methodological quality of each included studies was assessed. We calculated the pooled ORs with their 95%CI for each genetic polymorphism in STATA 11 software. Separate analysis was performed to address the consistency of results across the subgroup with different continents. A total of 39 studies were included, with a sample of 42269 individuals. This meta-analysis provided evidence that genetic polymorphism of MMP1-1607 1G/2G, MMP3-Gly45lys, MMP3-376 G/C, MMP3-1171 5A/6A, MMP9-1562 C/T and MMP9-R279Q have a small to medium effect on incidence of coronary disease. There was no evidence that MMP1-519 A/G, MMP1-340 T/C and MMP2-1306 C/T polymorphism could increase risk of coronary disease. Results from subgroup analysis supported a relation between MMP3-1711 5A allele, MMP9-1562 C allele and coronary disease especially in Asian population. The results provide moderate association between the six common genetic polymorphism of matrix metalloproteinase family and coronary disease. However, the challenge for researcher is identifying separate effect on different races.

Matrix metalloproteinases in tumorigenesis: an evolving paradigm

Proteases are crucial for development, tissue remodeling, and tumorigenesis. Matrix metalloproteinases (MMPs) family, in particular, consists of more than 20 members with unique substrates and diverse function. The expression and activity of MMPs in a variety of human cancers have been intensively studied. MMPs have well-recognized roles in the late stage of tumor progression, invasion, and metastasis. However, increasing evidence demonstrates that MMPs are involved earlier in tumorigenesis, e.g., in malignant transformation, angiogenesis, and tumor growth both at the primary and metastatic sites. Recent studies also suggest that MMPs play complex roles in tumor progression. While most MMPs promote tumor progression, some of them may protect the host against tumorigenesis in a context-dependent manner. MMPs have been chosen as promising targets for cancer therapy on the basis of their aberrant up-regulation in malignant tumors and their ability to promote cancer metastasis. Although preclinical studies testing the efficacy of MMP suppression in tumor models were so encouraging, the results of clinical trials in cancer patients have been rather disappointing. Here, we review the complex roles of MMPs and their endogenous inhibitors such as tissue inhibitors of metalloproteinase in tumorigenesis and strategies in suppressing MMPs.

Relationships of plasma factor VIIa-antithrombin complexes to manifest and future cardiovascular disease

BACKGROUND

Low levels of free activated coagulation factor VII (VIIa) are normally present in plasma to prime the coagulation of blood in normal hemostasis and during thrombus formation. VIIa also circulates in inactive form, in complex with antithrombin (VIIaAT) formed when VIIa is bound to tissue factor (TF). This study evaluated VIIaAT in relation to cardiovascular disease (CVD).

METHODS

We determined the plasma VIIaAT concentration in samples from the Stockholm Coronary Atherosclerosis Risk Factor (SCARF) study, a population-based case-control study of myocardial infarction (MI) and in samples from the Stockholm study of 60-years-old individuals, a prospective study of CVD. VIIaAT was measured with a sandwich ELISA that captures the complex between a monoclonal antibody to VIIa and a polyclonal antibody to AT.

RESULTS

In the SCARF study (200 post-MI cases, 340 controls), VIIaAT was statistically significantly associated with patient status [odds ratio (95% confidence interval (CI)] 1.51 (1.09-2.08), p=0.0126). The case-control differences were however small, with VIIaAT values that largely overlap between the two groups. When a nested case-control design (211 incident CVD cases and 633 matched controls) was applied on 5- to 7-year follow-up results of the Stockholm prospective study of 60-year-olds, plasma VIIaAT concentration was not associated with incident CVD (odds ratio (95% CI) 1.001 (0.997-1.005), p=0.5447).

CONCLUSIONS

Plasma VIIaAT concentration had no predictive value for future CVD in our study population. Slightly increased plasma VIIaAT concentrations observed after MI may reflect processes that occur in connection with the acute event when TF and VIIa availability is increased.

The utility of collaborative biobanks for cardiovascular research

Differences between animal and human atherosclerosis have led to the requirement for clinical data, imaging information and biological material from large numbers of patients and healthy persons. Where such "biobanks" exist, they have been fruitful sources for genomewide association, diagnostic accuracy, ethnicity, and risk stratification cohort studies. In addition once established, they attract funding for future projects. Biobanks require a network of medical contributors, secure storage facilities, bioinformatics expertise, database managers, and ethical working practices to function optimally. There is the opportunity for collaboration between individual biobanks to further amplify the advantages afforded.

Plasma CD93 concentration is a potential novel biomarker for coronary artery disease

OBJECTIVES

A common nonsynonymous single nucleotide polymorphism (SNP) in the CD93 gene (rs3746731, Pro541Ser) has been associated with risk of coronary artery disease (CAD). CD93 is a transmembrane glycoprotein, which is detectable in soluble form in human plasma. We investigated whether the concentration of soluble CD93 in plasma is related to risk of myocardial infarction (MI) and CAD, using a case-control study of premature MI (n = 764) and a nested case-control analysis of a longitudinal cohort study of 60-year-old subjects (analysis comprising 844 of 4232 subjects enrolled at baseline). In addition, SNPs in the CD93 gene were studied in relation to plasma CD93 concentration and CD93 mRNA expression.

METHODS AND RESULTS

A sensitive and specific enzyme-linked immunosorbent assay was established for determination of the plasma CD93 concentration. Subjects were divided into three groups according to tertiles of the distribution of CD93 concentration. Lower odds ratios for risk of MI and incidence of CAD were observed in the middle CD93 tertile (142-173 μg L(-1) ): odds ratio (95% confidence interval), 0.69 (0.49-0.97) and 0.61 (0.40-0.94), respectively. These associations were independent of traditional CAD risk factors. The minor allele of a SNP in the 3' untranslated region of CD93 (rs2749812) was associated with increased plasma CD93 concentrations (P = 0.03) and increased CD93 mRNA expression levels (P = 0.02).

CONCLUSION

The results of the present study suggest that the concentration of soluble CD93 in plasma is a potential novel biomarker for CAD, including MI.

Genetic polymorphisms and plasma levels of matrix metalloproteinases and their relationships with developing acute myocardial infarction

OBJECTIVES

Matrix metalloproteinases (MMPs) play an important role in early atherosclerosis, plaque rupture, extracellular matrix remodeling, and myocardial infarction (MI). MMP gene polymorphisms contribute to the risk of developing cardiovascular disease. We designed to investigate the association of acute MI (AMI) with a polymorphism in the human MMP-1, 2, 3, and 9 genes in Iranian patients with AMI.

METHODS

Genomic DNA of 400 enrolled patients with AMI and 200 controls was extracted from their blood samples. The -1607 1G/2G MMP-1, -1306 C/T MMP-2, -1171 5A/6A MMP-3, -1562 C/T MMP-9 polymorphisms were detected. Plasma levels of MMPs were analyzed.

RESULTS

There are significant differences in MMP-3 '5A' allele and genotype in the patients with AMI comparing with controls. However, no significant differences were observed in MMP-1, 2, and 9 allele frequencies between the patients and controls. Differences between plasma levels of MMPs were significant in the patients than in controls. There were statistically significant differences between plasma MMP-3 in carriers of 5A allele compared with 6A allele. MMP-9 plasma levels were significantly higher in the carriers of -1306 TT and -1306 CT than CC. However, there were no statistically significant association between genetic variation of MMP-1, 2, and 3 in the patients and their plasma levels.

CONCLUSION

These data suggest that MMP genotyping such as genetic polymorphism in MMP-3 might be helpful in determining susceptibility to AMI in Iranian patients. In addition, susceptibility to AMI might be related to MMP-9 gene expression, which affects its plasma levels.

MMP-3 (5A/6A) polymorphism does not influence human smooth muscle cell invasion

BACKGROUND

Stromelysin (MMP-3) is an important regulator of vascular smooth muscle cell (SMC) invasion, a key contributor to saphenous vein (SV) bypass graft failure. The 5A allele of the common -1612 MMP-3 5A/6A promoter polymorphism reportedly confers increased promoter activity, MMP-3 tissue expression, and susceptibility to a number of vascular pathologies. The aim of this study was to determine whether the MMP-3 5A/6A polymorphism directly influences endogenous MMP-3 expression levels and, consequently, cell invasion, in SV-derived SMC cultured from patients with different genotypes.

MATERIAL AND METHODS

Genotyping of 226 patients revealed -1612 MMP-3 5A/6A genotype frequencies of 20.8% 5A/5A, 52.7% 5A/6A, and 26.5% 6A/6A. Using a standardized, controlled protocol, we investigated cytokine- and growth factor-induced MMP-3 expression (real-time polymerase chain reaction [RT-PCR], ELISA) and SV-SMC invasion (Boyden chamber with Matrigel barrier) using cultured SV-SMC from patients with different MMP-3 genotypes.

RESULTS

Despite observing a strong correlation between MMP-3 mRNA levels and MMP-3 protein secretion, no significant differences were apparent in MMP-3 expression levels or cell invasion between cells with different MMP-3 5A/6A genotypes.

CONCLUSIONS

Our data suggest that the MMP-3 5A/6A promoter polymorphism in isolation does not influence levels of MMP-3 secretion or cellular invasion in human SV-SMC.