Tissue inhibitor of metalloproteinase-1 (TIMP-1) polymorphisms in a Caucasian population with abdominal aortic aneurysm

Genetic and Epigenetic Mechanisms Underlying Vascular Smooth Muscle Cell Phenotypic Modulation in Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) refers to the localized dilatation of the infra-renal aorta, in which the diameter exceeds 3.0 cm. Loss of vascular smooth muscle cells, degradation of the extracellular matrix (ECM), vascular inflammation, and oxidative stress are hallmarks of AAA pathogenesis and contribute to the progressive thinning of the media and adventitia of the aortic wall. With increasing AAA diameter, and left untreated, aortic rupture ensues with high mortality. Collective evidence of recent genetic and epigenetic studies has shown that phenotypic modulation of smooth muscle cells (SMCs) towards dedifferentiation and proliferative state, which associate with the ECM remodeling of the vascular wall and accompanied with increased cell senescence and inflammation, is seen in in vitro and in vivo models of the disease. This review critically analyses existing publications on the genetic and epigenetic mechanisms implicated in the complex role of SMCs within the aortic wall in AAA formation and reflects the importance of SMCs plasticity in AAA formation. Although evidence from the wide variety of mouse models is convincing, how this knowledge is applied to human biology needs to be addressed urgently leveraging modern in vitro and in vivo experimental technology.

Association of TIMP-1 and COL4A4 Gene Polymorphisms with Keratoconus in an Iranian Population

PURPOSE

Keratoconus (KC) is a bilateral and noninflammatory disease, characterized by progressive thinning and anterior protrusion of the cornea and may result in severe visual impairment due to irregular astigmatism. Matrix metalloproteinases (MMP) are the main group of enzymes that degrade extracellular matrix proteins including collagens; Type IV collagen is found in the corneal stroma. MMP enzymatic activity is inhibited by tissue inhibitor of metalloproteinase-1 (TIMP-1). A decrease in TIMP-1 level is associated with the development of KC. In the present study, we investigated the impact of COL4A4 rs2228557 C/T and TIMP-1 rs4898 C/T (X-chromosome) variants on the odds of KC development in a sample of Iranian population.

METHODS

This case-control study was conducted on 140 patients with KC and 150 healthy control subjects. We used modified methods of Nested-PCR and ARMS-PCR in combination (Nested-ARMS-PCR) and confirmed their validity with RFLP-PCR.

RESULTS

Significant differences were noticed between KC patients and healthy individuals regarding the genotype TY or T allele frequencies of rs4898 in the male subjects (OR = 0.43, 95%CI: 0.20-0.92, P = 0.03), whereas no significant differences were identified in the female subjects (OR = 1.07, 95%CI: 0.52-2.20, P = 0.85). The rs2228557, T allele was associated with KC (OR = 0.69, 95% CI: 0.50-0.97, P = 0.035).

CONCLUSION

In the rs2228557 variant, T allele acts as a protective factor from the disease and decreases the risk of KC compared with the C allele. Also, in our investigation about rs4898, we found that TY genotype or T allele decreased the risk of KC compared with the C allele in males and was a protective factor for KC in our population.

Proteolysis is the most fundamental property of malignancy and its inhibition may be used therapeutically (Review)

The mortality rates of cancer patients decreased by ~1.5% per year between 2001 and 2015, although the decrease depends on patient sex, ethnic group and type of malignancy. Cancer remains a significant global health problem, requiring a search for novel treatments. The most common property of malignant tumors is their capacity to invade adjacent tissue and to metastasize, and this cancer aggressiveness is contingent on overexpression of proteolytic enzymes. The components of the plasminogen activation system (PAS) and the metal-loproteinase family [mainly matrix metalloproteinases (MMPs)] are overexpressed in malignant tumors, driving the local invasion, metastasis and angiogenesis. This is the case for numerous types of cancer, such as breast, colon, prostate and oral carcinoma, among others. Present chemotherapeutics agents typically attack all dividing cells; however, for future therapeutic agents to be clinically successful, they need to be highly selective for a specific protein(s) and act on the cancerous tissues without adverse systemic effects. Inhibition of proteolysis in cancerous tissue has the ability to attenuate tumor invasion, angiogenesis and migration. For that purpose, inhibiting both PAS and MMPs may be another approach, since the two groups of enzymes are overexpressed in cancer. In the present review, the roles and new findings on PAS and MMP families in cancer formation, growth and possible treatments are discussed.

Autoimmunity in the Abdominal Aortic Aneurysm and its Association with Smoking

Smoking increases the risk of abdominal aortic aneurysm (AAA) in both humans and mice, although the underlying mechanisms are not completely understood. An adventitial aortic antigen, AAAP-40, has been partially sequenced. It has motifs with similarities to all three fibrinogen chains and appears to be connected in evolution to a large family of proteins called fibrinogen-related proteins. Fibrinogen may undergo non-enzymatic nitration, which may result from exposure to nitric oxide in cigarette smoke. Nitration of proteins renders them more immunogenic. It has recently been reported that anti-fibrinogen antibody promotes AAA development in mice. Also, anti-fibrinogen antibodies are present in patients with AAA. These matters are reviewed in the overall context of autoimmunity in AAA. The evidence suggests that smoking amplifies an auto-immune reaction that is critical to the pathogenesis of AAA.

Abdominal Aortic Aneurysm Genetic Associations: Mostly False? A Systematic Review and Meta-analysis

OBJECTIVE/BACKGROUND

Many associations between abdominal aortic aneurysm (AAA) and genetic polymorphisms have been reported. It is unclear which are genuine and which may be caused by type 1 errors, biases, and flexible study design. The objectives of the study were to identify associations supported by current evidence and to investigate the effect of study design on reporting associations.

METHODS

Data sources were MEDLINE, Embase, and Web of Science. Reports were dual-reviewed for relevance and inclusion against predefined criteria (studies of genetic polymorphisms and AAA risk). Study characteristics and data were extracted using an agreed tool and reports assessed for quality. Heterogeneity was assessed using I(2) and fixed- and random-effects meta-analyses were conducted for variants that were reported at least twice, if any had reported an association. Strength of evidence was assessed using a standard guideline.

RESULTS

Searches identified 467 unique articles, of which 97 were included. Of 97 studies, 63 reported at least one association. Of 92 studies that conducted multiple tests, only 27% corrected their analyses. In total, 263 genes were investigated, and associations were reported in polymorphisms in 87 genes. Associations in CDKN2BAS, SORT1, LRP1, IL6R, MMP3, AGTR1, ACE, and APOA1 were supported by meta-analyses.

CONCLUSION

Uncorrected multiple testing and flexible study design (particularly testing many inheritance models and subgroups, and failure to check for Hardy-Weinberg equilibrium) contributed to apparently false associations being reported. Heterogeneity, possibly due to the case mix, geographical, temporal, and environmental variation between different studies, was evident. Polymorphisms in nine genes had strong or moderate support on the basis of the literature at this time. Suggestions are made for improving AAA genetics study design and conduct.

Current status of medical treatment for abdominal aortic aneurysm

Although cardiovascular disease is widely recognized as the leading cause of death, a lesser known fact is that aortic aneurysm is the 15th leading cause of death over the age of 65 years in the USA. The golden standard of the treatments are invasive interventions either with open surgical repair (OS) or endovascular aneurysm repair (EVAR). The concept of medical treatment is to prevent abdominal aortic aneurysm (AAA) from rupture and avoid surgical treatment by preventing aneurysm enlargement or even reducing aneurysm size. Matrix metalloproteinases (MMP) are structurally related metalloendopeptidases that can degrade the extracellular matrix and is thought to play important roles in AAA. There are many proposed pharmacological treatments including: β-blockers, angiotensin-converting enzyme inhibitor (ACE inhibitors), angiotensin-receptor blocker (ARB), statins, macrolides and, doxycycline, an inhibitor of the MMP. The latter is a potential promising drug as medical treatment for AAA and the Non-invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA(3)CT) is currently ongoing in the USA. Here, the pathophysiology and potential medical therapy for AAA will be reviewed.

TIMP-1 polymorphisms in a Chinese Han population with intracerebral hemorrhage

Remodeling of extracellular matrix (ECM) and breakdown of blood-brain barrier (BBB) are crucial events in the pathogenesis of intracerebral hemorrhage (ICH). Matrix metalloproteinases (MMPs), particularly MMP-9 and MMP-2, are the most important degrading enzymes in the ECM and BBB. These proteolytic effects are controlled predominantly by tissue inhibitors of metalloproteinases (TIMPs). TIMP-1 is the main endogenous inhibitor of MMP-9. Two polymorphisms in the TIMP-1 gene (rs4898 and rs2070584) were selected through a literature review and successfully genotyped in a study sample of 410 ICH patients and 305 controls. Differences in genotype and allele frequencies of identified polymorphisms were determined. Furthermore, the serum levels of TIMP-1 were measured in a subgroup of 96 ICH patients on days 1 after ICH onset and 76 controls. Analyses showed that C allele of rs2070584 was significantly associated with the development of ICH in male subjects (p = 0.037, OR = 1.535, 95%CI 1.025-2.300). Multiple logistic regression analysis under three genetic models demonstrated both rs4898 and rs2070584 were not risk factors for ICH in female subjects. Furthermore, serum levels of TIMP-1 were significantly higher in ICH patients than those in normal controls. However, the serum levels of TIMP-1 showed a nonsignificant decrease, depending on the alleles and genotypes of rs2070584 both in male and female cases. In conclusion, this is the first association study of the TIMP-1 gene variants with ICH. Our data suggest that C allele of rs2070584 is a risk factor for ICH development in the Chinese male population. However, the precise function of this variant needs further investigation.

Exposure to environmental tobacco smoke, human E-cadherin C-160A polymorphism, and childhood asthma

BACKGROUND

Environmental tobacco smoke (ETS) is a risk factor for asthma. Importantly, cigarette smoke can decrease the adherence of epithelial cells and increase detachment. The adhesion molecule E-cadherin (CDH1) has an essential role in the formation of epithelial junction. Turnover of the extracellular matrix, which is characterized by airway remodeling, depends on the imbalance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs).

OBJECTIVE

To evaluate the effects of ETS exposure and CDH1, MMP-3, and TIMP-1 genetic polymorphisms on childhood asthma.

METHODS

The CDH1 C-160A, MMP-3 -1171, and TIMP-1 T372C genotypes were identified by polymerase chain reaction in 299 asthmatic children and 383 healthy controls.

RESULTS

More ETS exposure (>5 vs 0 cigarettes/day; odds ratio [OR], 1.45; 95% confidence interval [CI], 1.05-2.01) and the presence of CDH1 AA/CA genotypes (OR, 1.53; 95% CI, 1.08-2.17) were associated with childhood asthma. Compared with children with less ETS exposure (0-5 cigarettes/day) and the CDH1 CC genotype, those with less ETS exposure and the CDH1 AA/CA genotypes and those with more ETS exposure and the CDH1 CC genotype had a moderate risk of asthma. The greatest risk for asthma was in children with more ETS exposure and the CDH1 AA/CA genotypes (OR, 3.03; 95% CI, 1.81-5.06), and this interaction between CDH1 polymorphism and ETS exposure was significant. In addition, asthma cases with more ETS exposure or the CDH1 AA/CA genotypes had obviously increased eosinophil counts.

CONCLUSION

Susceptible CDH1 genotypes might modulate the development of asthma, especially for children exposed to ETS.

Association of TIMP-1 and TIMP-2 gene polymorphisms with progression of liver fibrosis in patients with type C chronic liver disease

We examined the association of TIMP-1 and TIMP-2 gene polymorphisms with the progression of chronic liver disease related to the hepatitis C virus (HCV). We used PCR to analyze 188 patients with HCV-related liver disease (95 with chronic hepatitis and 93 with cirrhosis) for TIMP-1 372 T/C and TIMP-2 -418 G/C polymorphisms. Comparing chronic hepatitis and cirrhosis, there were no significant differences in TIMP-1 and TIMP-2 gene polymorphisms. Among chronic hepatitis patients, TIMP-2 -418 G homozygotes showed significantly faster fibrosis progression than C carriers. Among cirrhotic patients, males with the TIMP-1 372 T allele developed cirrhosis at a younger age, and patients who were homozygous for the higher-transcription TIMP-2 -418 G allele had significantly lower serum albumin concentrations. These results suggest that faster progression of liver fibrosis could be associated with TIMP-2 -418 G homozygotes.

The α(1)AT and TIMP-1 Gene Polymorphism in the Development of Asthma

Asthma has been an inflammatory disorder accompanied by tissue remodeling and protease-antiprotease imbalance in lungs. The SNPs of alpha-1 antitrypsin (α(1)AT) and tissue inhibitor of metalloproteinase-1 (TIMP-1) genes were studied for their association with asthma. Genotyping of α(1)AT and TIMP-1 genes was performed in 202 asthmatics and 204 controls. Serum levels of α(1)AT, TIMP-1 and cytokines were estimated to find if the interplay between genotypes and cellular biomarkers determines the pathogenesis of asthma. The analysis of results showed significantly low level of α(1)AT in the serum of asthmatics as compared to controls (P = 0.001), whereas cytokines were elevated in patients. No significant difference was observed in the concentration of TIMP-1 in patients and controls. Genotyping led to the identification of 3 SNPs (Val213Ala, Glu363Lys, and Glu376Asp) in α(1)AT gene. The novel SNP Glu363Lys of α(1)AT was found to be associated with asthma (P = 0.001). The analysis of TIMP-1 gene showed the occurrence of seven SNPs, including a novel intronic SNP at base G3774A. The allele frequency of G3774A and Phe124Phe was significantly higher in asthmatics as compared to controls. Thus, the SNP Glu363Lys of α(1)AT and G3774A and Phe124Phe of TIMP-1 could be important genetic markers for use in better management of the disease.

The association between levels of tissue inhibitor of metalloproteinase-1 with acute heart failure and left ventricular dysfunction in patients with ST elevation myocardial infarction treated by primary percutaneous coronary intervention

AIMS

Tissue inhibitors of metalloproteinase (TIMPs) bind to active matrix metalloproteinase (MMPs), and thereby inhibit their proteolytic activity. We investigated the role of polymorphisms in the gene for TIMP-1 and serum levels of TIMP-1 in association with postmyocardial infarction (MI), left ventricular (LV) dysfunction, and symptoms of acute heart failure (AHF) in patients treated with primary percutaneous coronary intervention.

METHODS

In total, 556 patients with STEMI were evaluated. Levels of TIMP-1 were measured at admission and 24 h after MI onset. The TIMP-1 exon 5 SNP rs4898 (F124F with T>C) located at X chromosome was assayed.

RESULTS

TIMP-1 levels were higher for men with AHF as well as for men with LV dysfunction (ejection fraction [EF]<40%). According to multivariate analysis, the TIMP-1 level was a factor with an independent negative relationship to EF and AHF in men. An independent relationship between exon 5 TIMP-1 gene polymorphism and EF, AHF or TIMP-1 level was not documented.

CONCLUSION

These results provide evidence that a higher level of circulating TIMP-1 is independently associated with worse EF and AHF.

Combinatorial effect of TIMP-1 and α1AT gene polymorphisms on development of chronic obstructive pulmonary disease

OBJECTIVE

To study the role of α(1)AT and TIMP-1 gene polymorphisms in development of COPD.

DESIGN AND METHODS

Blood samples from total 408 subjects (217 COPD patients and 191 controls) were used for genotyping and estimating biolevels of α(1)AT, TIMP-1 and inflammatory cytokines. Data was analyzed to determine the role of interaction of TIMP-1 and α(1)AT genes; and interplay between various genotypes and biolevels of α(1)AT, TIMP-1 and inflammatory cytokines in development of COPD.

RESULTS

Significantly low levels of α(1)AT and TIMP-1 were observed in COPD patients as compared to controls (P = 0.001), where as the inflammatory cytokines were found to be increased in patients. PIM3 allele of α(1)AT gene in COPD patients was found to be associated with low levels of α(1)AT (P = 0.001), the effect being more pronounced when PIM3 combined with rs6609533 of TIMP-1 gene (P = 0.0001). Combination of genotypes rs6609533 of TIMP-1 and PIM3 of α(1)AT containing the risk alleles was over-represented in patients (P = 0.005).

CONCLUSION

The SNP rs6609533 of TIMP-1 gene interacted with PIM3 of α(1)AT to make a possible risk combination for development of COPD.

Single-nucleotide polymorphisms of matrix metalloproteinases and their inhibitors in gastrointestinal cancer

Matrix metalloproteinases (MMPs) are implicated in cancer development and progression and are associated with prognosis. Single-nucleotide polymorphisms (SNPs) of MMPs, most frequently located in the promoter region of the genes, have been shown to influence cancer susceptibility and/or progression. SNPs of MMP-1, -2, -3, -7, -8, -9, -12, -13 and -21 and of the tissue inhibitor of metalloproteinases (TIMPs) TIMP-1 and TIMP-2 have been studied in digestive tract tumors. The contribution of these polymorphisms to the cancer risk and prognosis of gastrointestinal tumors are reviewed in this paper.

Genes and abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is a multifactorial disease with a strong genetic component. Since the first candidate gene studies were published 20 years ago, approximately 100 genetic association studies using single nucleotide polymorphisms (SNPs) in biologically relevant genes have been reported on AAA. These studies investigated SNPs in genes of the extracellular matrix, the cardiovascular system, the immune system, and signaling pathways. Very few studies were large enough to draw firm conclusions and very few results could be replicated in another sample set. The more recent unbiased approaches are family-based DNA linkage studies and genome-wide genetic association studies, which have the potential of identifying the genetic basis for AAA, only when appropriately powered and well-characterized large AAA cohorts are used. SNPs associated with AAA have already been identified in these large multicenter studies. One significant association was of a variant in a gene called contactin-3, which is located on chromosome 3p12.3. However, two follow-up studies could not replicate this association. Two other SNPs, which are located on chromosome 9p21 and 9q33, were replicated in other samples. The two genes with the strongest supporting evidence of contribution to the genetic risk for AAA are the CDKN2BAS gene, also known as ANRIL, which encodes an antisense ribonucleic acid that regulates expression of the cyclin-dependent kinase inhibitors CDKN2A and CDKN2B, and DAB2IP, which encodes an inhibitor of cell growth and survival. Functional studies are now needed to establish the mechanisms by which these genes contribute toward AAA pathogenesis.

Abdominal aortic aneurysm: a review of the genetic basis

BACKGROUND

Abdominal aortic aneurysm (AAA) is a complex disease with a largely unknown pathophysiological background and a strong genetic component. Various studies have tried to link specific genetic variants with AAA.

METHODS

Systematic review of the literature (1947-2009).

RESULTS

A total of 249 studies were identified, 89 of which were eventually deemed relevant to this review. Genetic variants (polymorphisms) in a wide variety of genes, most of which encode proteolytic enzymes and inflammatory molecules, have been associated with AAA development and progression.

CONCLUSION

The genetic basis of AAA remains unknown, and most results from ''candidate-gene'' association studies are contradictory. Further analyses in appropriately powered studies in large, phenotypically well-characterized populations, including genome-wide association studies, are necessary to elucidate the exact genetic contribution to the pathophysiology of AAA.

Markers of Proteolysis, Fibrinolysis, and Coagulation in Relation to Size and Growth Rate of Abdominal Aortic Aneurysms

We evaluated whether matrix metalloproteinases (MMPs) 2 and 9, their inhibitors, markers for fibrinolysis, and thrombin activation are associated with diameter and growth of abdominal aortic aneurysms (AAAs). Material and Methods: Matrix metalloproteinases 2 and 9, tissue inhibitor of MMPs (TIMP-1), serpine-1, tPa-serpine-1, and activated protein C— protein C inhibitor (APC-PCI) complex were analyzed in 353 patients with AAA grouped according to AAA size, and 219 gender- and age-matched healthy individuals. Follow-up of AAA growth for up to 7 years was possible in 178 of 353 patients. Results: At baseline, all groups of patients with AAA showed lower levels of MMP-2 and -9, and higher levels of TIMP-1, serpine-1, and t-Pa-serpine-1 than controls. Matrix metalloproteinase 2 correlated inversely and APC-PCI complex correlated directly with AAA diameter. We found no correlations between markers for proteolysis, fibrinolysis, coagulation, and yearly AAA growth. Conclusion: Matrix metalloproteinase 2 is lower and APC-PCI higher in patients with larger AAA, but the relevance of the markers for AAA growth is far from clarified.

Genetic polymorphisms of the matrix metalloproteinase-3 (MMP-3) and tissue inhibitors of matrix metalloproteinases-1 (TIMP-1) modulate the development of ankylosing spondylitis

BACKGROUND

The aetiology of ankylosing spondylitis (AS) remains unclear. Inflammation progresses to fibrosis and calcification of the spine and sacroiliac joints in AS development. Fibrosis results from excessive accumulations of the extracellular matrix (ECM). ECM turnover depends on the balance between matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs).

OBJECTIVE

To evaluate the effects of the MMP-3 -1171 and TIMP-1 372 T>C polymorphisms on the modified risk of AS.

METHODS

Genotypes of 241 patients with AS and 241 controls were identified by PCR. Disease activity and functional status were assessed by the Bath Ankylosing Spondylitis Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI) and the Bath Ankylosing Spondylitis Global (BAS-G) Score.

RESULTS

MMP-3 6A/6A carriers had a 2.41-fold (95% confidence interval (CI) 1.55 to 3.74) increased risk of AS compared with 6A/5A and 5A/5A carriers. TIMP-1 C alleles had a greater risk of AS, but this was not significant (odds ratio (OR) = 1.28, 95% CI 0.92 to 1.77). Pairwise analysis of the MMP-3/TIMP-1 alleles showed that 6A/C (OR = 3.23, 95% CI 1.50 to 6.95) and 6A/T (OR = 2.55, 95% CI 1.17 to 5.54) had a significantly greater risk of AS than the 5A/T alleles. After adjustment for the effects of age, gender and disease duration, the MMP-3/TIMP-1 5A/T alleles had the lowest BASDAI (p = 0.02), BASFI (p = 0.05) and BAS-G (p = 0.02) among all MMP-3/TIMP-1 alleles.

CONCLUSION

The findings highlight the importance of the MMP-3 and TIMP-1 genes as crucial elements in AS development.

Matrix metalloproteinases and their tissue inhibitors as prognostic indicators for diagnostic and surgical recurrence in Crohn's disease

BACKGROUND

Recurrence of disease after surgically induced remission constitutes a major and largely unpredictable problem in Crohn's disease (CD). Matrix metalloproteinases (MMP) and the tissue inhibitors of metalloproteinases (TIMP) are involved in the (etio)pathogenesis of CD and may thereby also affect postsurgical outcome. We studied the predictive value of 1) allelic composition at MMP, TIMP, and TNF-alpha single nucleotide polymorphism loci, and 2) MMP and TIMP intestinal protein levels relative to important clinical variables for recurrence of CD after resection of diseased bowel.

METHODS

From 87 CD patients with a full medical record, surgically resected tissue was homogenized and analyzed for single nucleotide polymorphism (SNP) genotype and MMP-TIMP protein levels. The prognostic value of these parameters was determined using the uni- and multivariate Cox proportional hazards analyses.

RESULTS

The T allele at TIMP-1 SNP +372 T/C was found to be associated with an increased risk for surgical recurrence. Higher levels of TIMP-1, TIMP-2, and MMP-9 in noninflamed CD tissue, but not in inflamed tissue, and negative smoking status independently protected against diagnostic and/or surgical recurrence.

CONCLUSIONS

The TIMP-1 SNP +372 T allele with an increased risk of recurrence is in line with our previous results demonstrating increased CD susceptibility and low TIMP-1 protein expression associated with this allele. High TIMP and MMP-9 levels in noninflamed tissue are predictive of a favorable disease recurrence in CD. The contribution of MMP-9 and TIMPs to disease recurrence appears not to be mediated by smoking status, since no correlation with this parameter could be demonstrated.