MMP-8 polymorphism is genetic marker to tendinopathy primary posterior tibial tendon.

Posterior tibial tendon is particularly vulnerable and is responsible for much morbidity in sportspersons. Some patients have a predisposition without a clinically recognized cause, suggesting that individual characteristics, inclusive genetic inheritance, play an important role in tendinopathy. Matrix metalloproteinase (MMP)-8 is a proteinase capable of degrading a large amount of extracellular proteins, and influence degradation and remodeling of collagen. To determine whether the -799 polymorphism in the promoter of MMP-8 gene is associated with tendinopathy in posterior tibial tendon, 50 patients undergoing surgical procedures and anatomopathological diagnosis of degenerative lesions of the posterior tibial tendon and 100 control patients with posterior tibial tendon integrity and without signs of degeneration in magnetic resonance imaging were evaluated for the -799 MMP-8 polymorphism. There was a significant difference in the presence of the different alleles (P = 0.001) and genotype (P = 0.003) between the control group and the test group for the MMP-8 gene. The polymorphism at position -799 of the gene for MMP-8 is associated with tendinopathy primary posterior tibial tendon in the population studied. The results suggest that individuals with the T allele are at greater risk of developing tendinopathy.

MMP-3 polymorphism: Genetic marker in pathological processes (Review).

Matrix metalloproteinases (MMPs) are a family of zinc-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 controlled at multiple levels, and the transcriptional regulation of MMPs appears to represent a necessary step in its regulation. MMP-3 is a key member of the MMP family with broad substrate specificity, and is crucial to the connective tissue remodeling process. It is also involved in the turnover of the numerous ECM components. A common functional promoter polymorphism of MMP-3, 5A/6A, affects its activity and has been associated with various diseases. This polymorphism may be used as a genetic marker for certain pathologies to identify individual susceptibility. This review discusses various topics related to MMP-3 in pathological processes, with a focus on the 5A/6A polymorphism.

Association of polymorphisms in the carbonic anhydrase 6 gene with salivary buffer capacity, dental plaque pH, and caries index in children aged 7-9 years.

Carbonic anhydrase VI is a secreted enzyme that catalyzes the hydration of carbon hydroxide in saliva and other body fluids. This enzyme has been implicated in taste and gastrointestinal dysfunctions, tooth erosion, and caries. The purpose of this study was to analyze the allele and genotype distribution of three polymorphisms in the coding sequences of (CA6) gene and check for possible associations with salivary buffer capacity, number of decayed, missing, and filled teeth in deciduous and permanent teeth (dmft/DMFT, Decayed/Missing/Filled Teeth), plaque index (PI), and the plaque pH variation (DeltapH) in children aged 7-9 years. Two hundred and forty-five children from both genders, residents in area with fluoridated water (Piracicaba, São Paulo, Brazil) were divided into two groups: caries free and with caries. The clinical examinations were conducted by a single previously calibrated examiner (kappa=0.91) in an outdoor setting using a mirror and a probe, according to WHO criteria index (dmft/DMFT). Approximately 2 h after the first daily meal, the buffer capacity (BC) and the plaque pH were analyzed by means of a pH meter and an ion selective electrode. Plaque pH was measured immediately and 5 min after a mouth rinse with a 10% sucrose solution. The data were submitted to chi(2), Student's, and Mann-Whitney tests (alpha=0.05). The PI and DeltapH of the upper and lower teeth were significantly higher in the carious group than control (P<0.05). There was no difference between the groups in relation to BC. There was no association between the alleles and genotypes distributions for polymorphisms in the CA6 gene exons 2 and 3 and caries experience (P>0.05). There was a positive association between buffer capacity and the rs2274327 (C/T) polymorphism. The allele T and genotype TT were significantly less frequent in individuals with the highest buffer capacity (P=0.023 and 0.045, respectively). This finding encourages future studies relating CA6 gene polymorphisms and their association with malfunctions, such as taste and gastrointestinal alterations, or the differential effect of chemical modulators on the protein products originated from the distinct genotypes of the CA6 gene.

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.

Parathyroid hormone administration may modulate periodontal tissue levels of interleukin-6, matrix metalloproteinase-2 and matrix metalloproteinase-9 in experimental periodontitis.

BACKGROUND AND OBJECTIVE: Intermittent administration of the parathyroid hormone (1-34) has an anabolic effect on bone and it has been shown to reduce alveolar bone loss in experimental periodontitis models. The aim of the present study was to investigate the effect of parathyroid hormone on tissue degradation-related factors in an experimental periodontitis model in rats. MATERIAL AND METHODS: Periodontitis was induced in seventy-six male Wistar rats using ligature around the lower right first molars. The animals were then treated with parathyroid hormone (1-34) (T-group) or vehicle (C-group), three times a week for 15 d (C15, T15) or 30 d (C30, T30). At each experimental time-point, the 19 rats were killed in each group and the gingival tissue around the first lower molar was removed and prepared for the following analyses: mRNA expression of interleukin-1 beta, interleukin-6, matrix metalloproteinase (MMP)-2 and MMP-9, and gelatinolytic activity of MMP-2 and MMP-9. Hemimandibles were decalcified, and serial sections were processed and analyzed for interleukin-6 immohistochemistry. Samples were also histochemically stained by tartrate-resistant acid phosphatase (TRAP) to evaluate the number of osteoclasts present. RESULTS: Parathyroid hormone-treated samples showed decreased of levels of mRNA for interleukin-6 in the T30 group (p < 0.01) and of MMP-2 in the T15 and T30 groups (p < 0.05). Zymography assays demonstrated that treatment with parathyroid hormone led to a decrease in MMP-9 activity (p < 0.01). TRAP staining of alveolar bone revealed that osteoclasts were present in higher numbers (p < 0.05) in the groups not treated with parathyroid hormone. CONCLUSION: These data suggest that intermittent administration of parathyroid hormone can down-regulate the expression of biomarkers responsible for connective tissue breakdown and bone resorption, and potentially affect alveolar bone resorption activity.

Inhibition of human pulpal gelatinases (MMP-2 and MMP-9) by zinc oxide cements.

The interaction between metal ions and the oral environment is a major subject matter in dental research. Matrix metalloproteinases (MMPs) have been implicated in several pathological and physiological processes such as, periodontal tissue destruction, root caries, dentin calcification and pulpal inflammation. The aim of this work was to test the effect of zinc released from zinc oxide-eugenol (ZOE) cements, on the activity of the major pulpal gelatinolytic MMPs. Pulpal explants were cultured overnight in Dulbecco's Modified Eagle Medium and the activity of secreted enzymes was analysed by gelatin zymography in buffer conditioned with diverse ZOE cements. Phenanthroline, a zinc chelator, was used to revert the inhibition of MMPs caused by zinc. The major gelatinolytic proteinases present in the conditioned media were characterized as MMP-2 and MMP-9 by immunoprecipitation. All ZOE cements inhibited MMPs activity, whereas phenanthroline could partially revert the inhibition caused by plain ZOE and Intermediate Restorative Material (IRM).