Variation in the matrix metalloproteinase-3, -7, -12 and -13 genes is associated with functional status in rheumatoid arthritis

Association between matrix metalloproteinase-9-1562C/T gene polymorphism and MMP-9 serum level in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease indicated by joint inflammation and cartilage destruction. Matrix metalloproteinase (MMP) enzymes play an influential role in inflammation by affecting the invasion and degradation of anatomical barriers. In this way, the current study investigated the relationship between the MMP-9-1562C/T gene polymorphism and this enzyme's serum level in RA.

METHODS

The serum levels of MMP-9 in RA patients and healthy controls were measured using the enzyme-linked immunosorbent assay (ELISA). RA was confirmed using rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and C-reactive protein (CRP). Then the MMP-9-1562C/T gene polymorphism was analyzed utilizing polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Also, multivariate analysis investigated the connection between this polymorphism and the risk of RA.

RESULTS

In this study, the increase of MMP-9 in patients due to the development of single nucleotide polymorphism in the promoter region of this gene (-1562 C→T) was confirmed by increasing the frequency of heterozygous genotype (CT). Logistic regression analysis also demonstrated that the chance of development of RA is higher in people with CT/CC genotype than in other alleles.

CONCLUSIONS

We demonstrated that MMP-9-1562C/T gene polymorphism can play a significant role in the occurrence of RA.

MMP3 single-nucleotide polymorphisms are associated with noncontact ACL injuries in competing high-level athletes

Matrix metalloproteinases (MMPs) play an important role in matrix remodeling, as well as in ligament integrity. Anterior cruciate ligament (ACL) rupture is a severe and frequent knee injury in sports. The aim of this study was to investigate polymorphisms within the MMP3 gene with the predisposition for noncontact ACL rupture in the Croatian professional athletes. One hundred eighty-seven (95 with ACL rupture occurring through a noncontact mechanism and 92 asymptomatic controls) unrelated Caucasians were recruited between 2016 and 2017. All participants were genotyped for three single-nucleotide polymorphisms (SNP) within the MMP3 gene: rs591058 C/T, rs650108 A/G, and rs679620 G/A using the pyrosequencing method. For all three investigated SNPs, genotype frequencies have significantly differed between cases and controls. The MMP3 rs591058 TT (p = 0.0012, odds ratio [OR] = 38.541, 95% confidence interval [CI] = 1.7024-8.7254), rs650108 GG (p = 0.0051, OR = 23.338, 95% CI = 1.2899-4.2226) and rs679620 AA (p = 0.0030, OR = 34.750, 95% CI = 1.5266-7.9101) genotypes, as well as haplotype variant T-G-A (p = 0.0104, OR = 1.71, 95% CI = 1.13-2.59) were significantly overrepresented in cases compared to controls. These results support association between functional variants within the MMP3 gene and the risk of ACL rupture. Still, further research is needed to corroborate these results in a larger population.

Interleukin-1 genetic polymorphisms in knee osteoarthritis: What do we know? A meta-analysis and systematic review

PURPOSE

Interleukin-1 is the main proinflammatory cytokine in osteoarthritis (OA). Several single-nucleotide polymorphisms (SNPs) within the IL-1 gene cluster (IL-1β, IL-1R1, and IL-1RN) have been determined, but their associations with knee OA remain poorly understood. The present study aimed to identify the associations between IL-1 SNPs and knee osteoarthritis.

METHODS

This meta-analysis and systematic review included all comparative studies published in the MEDLINE/PubMed, Embase, Google Scholar, and Cochrane Library databases. We performed a systematic search to identify relevant studies on the evaluation of the correlation between the IL-1 gene and knee OA published up to February 2020 that met the eligibility criteria. Nine studies on a total of 2256 knees with OA and 3527 healthy knees met the eligibility criteria. Results associated with IL-1A, IL-1B, IL-1R1, and IL-1RN SNPs were extracted and compared between knees with OA and healthy knees. Methodological quality was assessed using the Newcastle-Ottawa scale (NOS). All studies with fair or good quality were included.

RESULTS

The meta-analysis showed that the risk of knee OA is decreased by the IL-1RN*1 and IL-1RN*1/*1 genotypes and increased by the IL-1RN*2 and I-L1RN*1/*2 genotypes. The systematic review revealed only two studies associating the IL-1RN allele, none associating the IL-1B polymorphism, and only one study associating IL-1A and IL-1R1 polymorphisms with knee OA.

CONCLUSIONS

Several IL-1RN alleles and genotypes play a role in knee OA but other genetic variations in the IL-1 region were still conflicting in its association with knee OA.

Decreased H19, GAS5, and linc0597 Expression and Association Analysis of Related Gene Polymorphisms in Rheumatoid Arthritis

Long noncoding RNAs (lncRNAs) widely participate in human diseases by regulating gene transcription, modulating protein function, or acting as ceRNAs. Yet, their roles in rheumatoid arthritis (RA) remain obscure. In this study, the expression of three lncRNAs (H19, GAS5, and linc0597) in peripheral blood mononuclear cells (PBMCs) were detected in 77 RA patients and 78 controls using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The association of lncRNAs related gene polymorphisms with RA were evaluated in 828 RA patients and 780 controls using TaqMan single nucleotide polymorphism (SNP) genotyping assays. We observed that the expression levels of H19, GAS5 and linc0597 were down-regulated in PBMCs of RA patients, of which GAS5 level decreased in patients with hypocomplementemia, and negatively correlated with C-reactive protein (CRP) level in RA patients. Moreover, we highlighted two related potential functional SNPs, GAS5 rs6790 and linc0597 rs2680700 for associations with RA susceptibility. The precise roles of these lncRNAs in mechanism of RA remain to be further explored.

Haemophilus parasuis Infection Disrupts Adherens Junctions and Initializes EMT Dependent on Canonical Wnt/β-Catenin Signaling Pathway

In this study, animal experimentation verified that the canonical Wnt/β-catenin signaling pathway was activated under a reduced activity of p-β-catenin (Ser33/37/Thr41) and an increased accumulation of β-catenin in the lungs and kidneys of pigs infected with a highly virulent strain of H. parasuis. In PK-15 and NPTr cells, it was also confirmed that infection with a high-virulence strain of H. parasuis induced cytoplasmic accumulation and nuclear translocation of β-catenin. H. parasuis infection caused a sharp degradation of E-cadherin and an increase of the epithelial cell monolayer permeability, as well as a broken interaction between β-catenin and E-cadherin dependent on Wnt/β-catenin signaling pathway. Moreover, Wnt/β-catenin signaling pathway also contributed to the initiation of epithelial-mesenchymal transition (EMT) during high-virulence strain of H. parasuis infection with expression changes of epithelial/mesenchymal markers, increased migratory capabilities as well as the morphologically spindle-like switch in PK-15 and NPTr cells. Therefore, we originally speculated that H. parasuis infection activates the canonical Wnt/β-catenin signaling pathway leading to a disruption of the epithelial barrier, altering cell structure and increasing cell migration, which results in severe acute systemic infection characterized by fibrinous polyserositis during H. parasuis infection.

Association of matrix metalloprotease 1, 3, and 12 polymorphisms with rheumatic heart disease in a Chinese Han population

BACKGROUND

Rheumatic heart disease (RHD) is an autoimmune disease triggered by acute rheumatic fever (ARF). Matrix metalloproteinases (MMPs) play an important role in the modulation of immune responses. The purpose of this study was to evaluate the association of MMP1, 3, and 12 promoter polymorphisms with RHD in a Han population in Southern China since the 3 genes are localized on the same chromosome and have a combined effect.

METHODS

DNA samples were obtained from 90 adult patients with RHD and 90 control subjects. Polymorphisms in MMP1 (rs1799750), MMP3 (rs3025058), and MMP12 (rs2276109) were genotyped by direct sequencing. Differences in genotype and allele frequencies of these polymorphisms were compared between the cases and the controls using Unconditional logistic regression models and Chi-squared test.

RESULTS

The 2G/2G genotype of rs1799750 in MMP1 was associated with a significantly higher risk of RHD when compared with the 1G/1G genotype (OR = 3.227; 95% CI:1.118-9.31; p = 0.03). The frequency of allele 2G was higher in patients with RHD compared to the controls (69.4% vs. 58.9%; p = 0.048) No significant differences in genotype and allele frequencies of rs3025058 in MMP3 and rs2276109 in MMP12 were found between the patients with RHD and the controls (p > 0.05).

CONCLUSIONS

Our results suggest that rs1799750 in MMP1 might be a risk factor for RHD in a Han population in Southern China, and individuals carrying the 2G/2G genotype are likely more susceptible to RHD. In contrast, rs3025058 in MMP3 and rs2276109 in MMP12 might not contribute to the risk of developing RHD in this population. Further studies with larger samples and other ethnic populations are required to confirm these findings.

Lack of association of matrix metalloproteinase-3 gene polymorphism with susceptibility to rheumatoid arthritis: a meta-analysis

Background

Epidemiological studies have investigated the association between matrix metalloproteinase-3(MMP-3) gene-1171 5A/6A polymorphism and rheumatoid arthritis (RA), but the results were inconsistent. To evaluate the specific relationship, we performed a meta-analysis to clarify the controversies.

Methods

The relevant literatures dated to December 07th 2013 were retrieved from PubMed, EMBASE and the China National knowledge Infrastructure (CNKI) databases. The number of the alleles and genotypes for MMP-3 were obtained. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the association between MMP-3 5A/6A promoter polymorphism and RA. All of the statistical analyses were conducted by STATA11.0 software.

Results

A total of 6 case-control studies covering 1451 cases and 1239 controls were included in the final meta-analysis. There was no significant association between MMP-3 5A/6A promoter polymorphism and RA in all genetic models (for 6A versus 5A: OR = 1.19, 95% CI = 0.91-1.56, P = 0.203; 5A/6A versus 5A/5A: OR = 1.31, 95% CI = 0.89-1.92, P = 0.174; 6A/6A versus 5A/5A: OR = 1.78, 95% CI = 0.68-4.61, P = 0.238; the recessive model: OR = 1.48, 95% CI = 0.88-2.47, P = 0.141; and the dominant model: OR = 1.46, 95% CI = 0.71-3.00, P = 0.299). In the subgroup analysis by ethnicity, we obtained the similar results.

Conclusions

We systematically investigate the association between MMP-3-1171 5A/6A polymorphism and RA susceptibility; however, the results show a lack of correlation. Considering the small sample size and the selection bias existed in some studies, further studies are needed to confirm the findings.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-376) contains supplementary material, which is available to authorized users.

Association of matrix metalloproteinase-7A-181G variants with the risk of multiple sclerosis

Aim: To investigate the influence of matrix metalloproteinase-7 (MMP-7) A-181G on the risk of multiple sclerosis (MS) and neurological disability. Patients & methods: The variants of MMP-7 were studied in 126 MS patients and 190 healthy controls. Results: The MMP-7 G allele and AG+GG genotype significantly increased the risk of MS in females (odds ratio: 1.59; p = 0.011) and patients with the age at disease onset of ≤19 years (odds ratio: 8.77; p = 0.038), respectively. Patients with clinical course of secondary progressive MS carriers of AG genotype had higher mean Expanded Disability Status Scale (4.9 ± 0.85; p = 0.01) compared with carriers of AA genotype (3.75 ± 0.41). Conclusion: The MMP-7 A-181G polymorphism might be associated with susceptibility to MS in females and individuals with the age at disease onset of ≤19 years and with neurological disability in secondary progressive MS.

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 relationship of metalloproteinase gene polymorphisms and lung cancer

BACKGROUND

We analyzed the relationship between matrix metalloproteinase (MMP)-2, -7, and -13 gene expression and polymorphisms and disease susceptibility and prognosis in patients who had undergone surgery for non-small-cell lung cancers.

MATERIALS AND METHODS

The study group consisted of 132 patients who had undergone radical surgery for non-small-cell lung cancers. The control group consisted of 80 healthy volunteers. We isolated deoxyribonuclease samples for use in analyzing gene polymorphisms from pathology blocks for the patient group and from blood samples for the control group. We identified MMP gene polymorphisms with polymerase chain reaction and restriction fragment length polymorphisms. Results were compared with those of the control group to evaluate disease susceptibility, correlation with other clinical parameters, and with survival and prognosis by using appropriate statistical methods.

RESULTS

When we compared polymorphisms pertaining to MMP genes in healthy controls and lung tumor DNA, we observed a decrease in the MMP-2 (-735) polymorphism GG genotype and increases in the MMP-13 (A77G) polymorphism AG and GG genotypes (P = 0.008, P = 0.047, and P = 0.047, respectively). For the MMP-7 (-181) polymorphism, the genotype did not differ significantly for disease susceptibility. Median overall survival time was 25.5 mo in the MMP-13 AA/AG genotypes and 9.3 mo in the GG genotype.

CONCLUSIONS

Decreases in the MMP-2 (-735) polymorphism GG genotype and increases in the MMP-13 (A77G) polymorphism AG and GG genotypes increase the risk for lung cancer. Furthermore, the presence of the MMP-13 (A77G) polymorphism GG genotype is an unfavorable prognostic factor.

MMP expression in rheumatoid inflammation: the rs11568818 polymorphism is associated with MMP-7 expression at an extra-articular site

Matrix metalloproteinases (MMPs) contribute to the joint damage in rheumatoid arthritis (RA). Less is known of the involvement of MMPs at extra-articular sites of rheumatoid inflammation. We assessed the relative contribution from MMP-1, MMP-3, MMP-7 and MMP-12 to joint and extra-articular tissue destruction and inflammation by comparing gene expression in joint synovia and subcutaneous rheumatoid nodules from RA patients. Expression of MMP-1 and MMP-3 predominated in synovia, whereas MMP-12 expression was significantly higher in rheumatoid nodules. Markedly higher MMP-7 expression distinguished a subgroup of nodules that featured infiltrating monocyte/macrophage-producing MMP-7 protein. The high MMP-7 expression in nodules was associated with the single-nucleotide polymorphism (SNP) rs11568818 (-181A>G, MMP-7 promoter) and more active inflammation within the nodule lesions. Patients with such nodules had significantly earlier age of RA onset. Our findings indicate that the expression of MMP-1 and MMP-3 occurs relatively independent of the tissue microenvironment with substantial expression also at extra-articular sites. MMP-12 expression reflects the involvement of monocyte/macrophages in rheumatoid inflammation. Evidence for the association between the rs11568818 SNP and increased MMP-7 expression is restricted to nodules, which indicates that consequences of the MMP-7 polymorphism are likely to manifest within aspects of immune/inflammatory activity that are monocyte/macrophage-mediated.

Association of MMP-3 (-1612 5A/6A) polymorphism with knee osteoarthritis in Thai population

Osteoarthritis (OA) is a degenerative joint disorder resulting in destruction of articular cartilage, osteophyte formation, and subchondral bone sclerosis. In recent years, numerous genetic factors have been identified and implicated in causing osteoarthritis. One such genetic defect is a single nucleotide polymorphism at position -1612 of matrix metalloproteinase-3 (MMP-3) promoter region, known to lead to three possible genotypes, 5A/5A, 6A/6A, and 5A/6A. The purpose of this study was to investigate the association of MMP-3 -1612 5A/6A gene polymorphism with knee osteoarthritis in Thai population. Genotype distributions and allelic frequencies of MMP-3 -1612 5A/6A polymorphism were investigated in 200 participants (100 patients with knee osteoarthritis and 100 healthy controls). Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. There was no statistically significant difference between the groups with respect to genotype distribution (P > 0.05). The 5A allele frequency was indicated as 15.5 %, and 6A allele was as 84.5 % in OA patients, whereas it was 10-90 % in the control group. Accordingly, the present study has indicated that the -1612 5A/6A polymorphism genotypes of MMP-3 gene promoter do not play a role in the development of osteoarthritis in the Thai population.

Human matrix metalloproteinases: an ubiquitarian class of enzymes involved in several pathological processes

Human matrix metalloproteinases (MMPs) belong to the M10 family of the MA clan of endopeptidases. They are ubiquitarian enzymes, structurally characterized by an active site where a Zn(2+) atom, coordinated by three histidines, plays the catalytic role, assisted by a glutamic acid as a general base. Various MMPs display different domain composition, which is very important for macromolecular substrates recognition. Substrate specificity is very different among MMPs, being often associated to their cellular compartmentalization and/or cellular type where they are expressed. An extensive review of the different MMPs structural and functional features is integrated with their pathological role in several types of diseases, spanning from cancer to cardiovascular diseases and to neurodegeneration. It emerges a very complex and crucial role played by these enzymes in many physiological and pathological processes.

Variation of matrix metalloproteinase 1 and 3 haplotypes and their serum levels in patients with rheumatoid arthritis and osteoarthritis

The matrix metalloproteinases 1 and 3 (MMP1 and MMP3) are thought to be important in destructive joint changes seen in rheumatoid arthritis (RA) and osteoarthritis (OA) diseases. The aim of this study was to analyze whether functional polymorphisms in the promoter region of the MMP1 and MMP3 genes were associated with RA and OA. The MMP1 (-1607 1G/2G) and MMP3 (-1171 5A/6A) polymorphisms were screened by polymerase chain reaction-restriction fragment length polymorphism in 100 patients with (RA), 100 patients with (OA), and 100 controls. Serum MMP1 and MMP3 levels were measured by enzyme-linked immunosorbent assay. The results reported a significant difference between patients with OA and controls regarding allele distributions of MMP1 polymorphism, but not between patients with RA and controls. For MMP3 polymorphism, the 6A/6A genotype was significantly more frequent in patients with RA and OA than in controls. The haplotype 2G-6A, which carries the abnormal alleles, showed higher frequencies in the patients with RA and OA than in controls (28%, 30% and 8%, respectively). There were no significant differences in serum MMP1 and MMP3 levels between all studied groups. In conclusion, the MMP1 and MMP3 haplotypes may represent genetic determinants for RA and OA in the Egyptian population. The results suggest that MMP polymorphism genotypes may be more useful in predicting joint damage than measurement of serum concentrations of MMP1 and MMP3. Moreover, MMP1 and MMP3 polymorphisms may predict the activity and severity of these diseases.

Association and expression study of MMP3, TGFβ1 and COL10A1 as candidate genes for leg weakness-related traits in pigs

The present study was aimed to determine the association between metalloproteinase 3 (MMP3), transforming growth factor beta 1 (TGFβ1) and collagen type X alpha I (COL10A1) gene polymorphisms with traits related to leg weakness in pigs. Three hundred Duroc × Pietrain cross breds (DuPi) and 299 pigs of a commercial population (CP) were used for the experiment. DuPi animals were examined for 10 different traits describing leg and feet structure, osteochondrosis (OC) scores and bone density status. Data of OC score at condylus medialis humeri, condylus medialis femoris and distal epiphysis ulna regions of CP were used for association analysis. Significant association (P < 0.05) was found for MMP3 SNP (g.158 C>T) with OC at head of femur and bone mineral density in the DuPi population. Association (P < 0.05) was found between SNP of TGFβ1 (g.180 G>A) with rear leg score and the principle component denoting both OC and feet and leg scores in the DuPi population. No association was found between COL10A1 (g.72 C>T) and leg weakness related traits. The associations of SNPs with OC traits could not be confirmed in the commercial population. Expression analysis of the three candidate genes was performed to compare between healthy and OC. TGFβ1 was found to be highly expressed (P < 0.05) in the OC compared to healthy cartilages, but no significant different expressions were observed for MMP3 and COL10A1 genes. The present finding suggested that TGFβ1 and MMP3 genes variants have an effect on some of the leg weakness related traits.

Genetic polymorphisms of matrix metalloproteinase 3 in primary sclerosing cholangitis

BACKGROUND

The damaging cholestasis inherent to primary sclerosing cholangitis (PSC) results from bile duct stricturing because of progressive fibrosis. The matrix metalloproteinase 3 (MMP3) degrades a wide range of matrix components and is expressed by activated liver stellate cells, and so is a candidate for involvement with the fibrotic processes underlying PSC. Moreover, the MMP3 gene harbours polymorphisms associated with variation in its activity directly impacting clinical phenotypes.

AIMS

We aimed to examine the influence of MMP3 polymorphisms on PSC risk and progression.

METHODS

Nine single nucleotide polymorphisms (SNPs) tagging the common genetic variation of MMP3 were genotyped in 266 PSC patients and 407 controls. SNPs and inferred haplotypes were assessed for PSC association by logistic regression and score tests. The effect of SNPs on survival to liver transplant or death was analysed using Cox regression, and Kaplan-Meier curves were constructed.

RESULTS

No association of PSC with individual SNPs or haplotypes of MMP3 was detected. However, progression to death or liver transplant was significantly associated with homozygosity for minor alleles of rs522616, rs650108 and rs683878, particularly among PSC patients with concurrent ulcerative colitis (UC) (strongest in redundant SNPs rs650108/rs683878, hazard ratio=3.23, 95% confidence interval 1.45-7.25, P=0.004).

CONCLUSIONS

Genetic variation in MMP3 influences PSC progression, possibly in the context of coexisting UC. While the functional variants and specific mechanisms remain unknown, this finding implicates the turnover of the extracellular matrix as an important and variable component of PSC pathogenesis. Efforts to understand this process could form the basis for developing effective treatments, which are currently lacking for PSC.

Proteolytic release of the receptor for advanced glycation end products from in vitro and in situ alveolar epithelial cells

Although the receptor for advanced glycation end products (RAGE) has been used as a biological marker of alveolar epithelial cell injury in clinical studies, the mechanism for release of soluble RAGE from lung epithelial cells has not been well studied. Therefore, these studies were designed to determine the mechanism for release of soluble RAGE after lipopolysaccharide (LPS) challenge. For these purposes, alveolar epithelial cells from rat lungs were cultured on Transwell inserts, and LPS was added to the apical side (500 μg/ml) for 16 h on day 7. On day 7, RAGE was expressed predominantly in surfactant protein D-negative cells, and LPS challenge induced release of RAGE into the medium. This response was partially blocked by matrix metalloproteinase (MMP) inhibitors. Transcripts of MMP-3 and MMP-13 were upregulated by LPS, whereas RAGE transcripts did not change. Proteolysis by MMP-3 and MMP-13 resulted in soluble RAGE expression in the bronchoalveolar lavage fluid in the in situ rat lung, and this reaction was inhibited by MMP inhibitors. In human studies, both MMP-3 and -13 antigen levels were significantly correlated with the level of RAGE in pulmonary edema fluid samples. These results support the conclusion that release of RAGE is primarily mediated by proteolytic damage in alveolar epithelial cells in the lung, caused by proteases in acute inflammatory conditions in the distal air spaces.

MMP-1 polymorphism and its relationship to pathological processes

Matrix metalloproteinases (MMPs) are a family of zinc (Zn)-dependent endopeptidases that are collectively capable of cleaving virtually all extracellular matrix (ECM) substrates and play an important role in diverse physiological and pathological processes. The activity of MMPs is regulated at multiple levels. The transcriptional regulation of MMP appears to represent the key step in MMP regulation. There are diverse types of MMPs that differ structural and functionally. MMP-1 is the most ubiquitously expressed interstitial collagenase and has a prominent role in initial cleavage of the ECM. The level of MMP-1 expression can be influenced by different single-nucleotide polymorphisms (SNPs) in the promoter region. A functional polymorphism at position -1607 has been shown to alter the transcriptional activity of MMP-1 and was associated with diverse pathological processes. The aim of our review was to discuss some topics related to MMP in physiological and pathological processes, with a focus on MMP-1 polymorphism.

Polymorphism of matrix metalloproteinase genes (MMP1 and MMP3) in patients with varicose veins

BACKGROUND

Several risk factors for varicose veins have been identified: female gender, combined with obesity and pregnancy, occupations requiring standing for long periods, sedentary lifestyle, history of deep-vein thrombosis and family history. However, no specific gene variants related to a wide prevalence of varicosities in general population have been identified. Extracellular matrix composition, predominantly maintained by matrix metalloproteinases (MMPs), may affect the vein-wall structure, which may lead to dilation of vessels and cause varicosities.

AIMS

MMP-1 (tissue collagenase I) and MMP-3 (stromelysin I) expression was found to be raised in varicose veins compared with normal vessels. Therefore, a study was conducted to evaluate a potential association between MMP1 and MMP3 promoter polymorphisms and a risk of varicose veins.

METHODS

Genotyping for the presence of the polymorphisms -1607dupG (rs1799750) in MMP1 and -1171dupA (rs3025058) in the MMP3 promoter region was performed using PCR and restriction-fragment length polymorphism assays in a group of 109 patients diagnosed with varicose veins and 112 healthy controls.

RESULTS

The frequencies of the MMP1 and MMP3 alleles (minor allele frequency 0.440 in patients vs. 0.451 in the controls for MMP1-1607*G and 0.514 vs. 0.469 for MMP3-1171*dupA, respectively) and of genotypes did not differ significantly between patients and controls.

CONCLUSIONS

The MMP1-1607dupG and MMP3-1171dupA promoter polymorphisms are not valuable markers of susceptibility for varicose veins.

Matrix metalloproteinase gene polymorphisms in patients with rheumatoid arthritis

Several genetic factors seem to be involved in the pathogenesis of rheumatoid arthritis (RA). The aim of this study was to analyze whether functional polymorphisms in the promoter region of the MMP-1, -3 and -9 genes were associated with RA. The study population comprises 110 RA patients and 100 healthy controls. The -1607 1G/2G MMP-1, -1171 5A/6A MMP-3, and -1562 C/T MMP-9 polymorphisms were analyzed. The frequency of the 5A allele of MMP-3 gene was significantly higher in the controls when compared with the RA patients (0.45 vs. 0.32, P < 0.01). No significant differences were observed in the allele frequencies for the MMP-1 and -9 polymorphisms between RA patients and controls. Individuals carrying MMP-3 5A allele have significant higher frequency of extra-articular manifestations and rheumatoid nodules than individuals homozygous for 6A allele (P < 0.05). The results presented in this study provide evidence of an association between the MMP-3 gene polymorphism and RA.

Progress in matrix metalloproteinase research

Matrix metalloproteinases (MMPs) are now acknowledged as key players in the regulation of both cell-cell and cell-extracellular matrix interactions. They are involved in modifying matrix structure, growth factor availability and the function of cell surface signalling systems, with consequent effects on cellular differentiation, proliferation and apoptosis. They play central roles in morphogenesis, wound healing, tissue repair and remodelling in response to injury and in the progression of diseases such as arthritis, cancer and cardiovascular disease. Because of their wide spectrum of activities and expression sites, the elucidation of their potential as drug targets in disease or as important features of the repair process will be dependent upon careful analysis of their role in different cellular locations and at different disease stages. Novel approaches to the specific regulation of individual MMPs in different contexts are also being developed.