The role of an MMP inhibitor in the regulation of mechanical tension by Dupuytren's disease fibroblasts

MMP-1, MMP-8, and MMP-13 Gene Polymorphisms and Haplotype Is a Risk Factor for Dupuytren Contracture: A Case-Control Study

BACKGROUND

There is an increased tissue expression of matrix metalloproteinases (MMPs) on Dupuytren contracture (DC). Genetic polymorphisms (single nucleotide polymorphism [SNPs]) in genes of these enzymes may individually influence these transcriptions. Haplotype analysis, which is the observation of a group of alleles, could be more useful to identify the association between SNPs and DC. The purpose of this study was to evaluate the influence of MMP-1 g.-1607 G>GG (rs1799750), MMP-8 g.-799 C>T (rs11225395), and MMP-13 g.-77 A>G (rs2252070) SNPs individually and in haplotype on DC.

METHODS

A total of 60 patients with a clinical diagnosis of DC were evaluated and matched, according to age and gender, with the control group of 100 patients without this clinical diagnosis. Genomic DNA was extracted from saliva samples, and genotypes were obtained by polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis of the results included Mann-Whitney U test, Chi-squared test, and PHASE and R software, with a significance level of 5%.

RESULTS

The 3 SNPs studied showed significant differences in allele and genotype frequencies between the groups: 2G in MMP-1 (P = .018; odds ratio [OR] 1.80 (95% confidence interval [CI], 1.13-2.88)), T in MMP-8 (P = .015; OR 0.53 (95% CI, 0.33-0.88)), and A in MMP-13 (rs2252070) SNPs (P = .040, OR 0.54 (95% CI, 0.33-0.90)) are risk alleles. The global haplotype analysis indicated a significant difference between both groups.

CONCLUSIONS

In conclusion, MMP-1 g.-1607 G>GG (rs1799750), MMP-8 g.-799 C>T (rs11225395), and MMP-13 g.-77 A>G (rs2252070) SNPs, individually and in haplotype, are a risk factor for DC, indicating that these SNPs may be a potential diagnostic and prognostic factor for DC.

The Deep Fascia and its Role in Chronic Pain & Pathological Conditions: A Review

INTRODUCTION

The deep fascia is a three-dimensional continuum of connective tissue surrounding the bones, muscles, nerves and blood vessels throughout our body. Its importance in chronically debilitating conditions has recently been brought to light. This work investigates changes in these tissues in pathological settings.

MATERIALS AND METHODS

A state-of-the-art review was conducted in PubMed and Google Scholar following a two-stage process. A first search was performed to identify main types of deep fasciae. A second search was performed to identify studies considering a deep fascia, common pathologies of this deep fascia and the associated alterations in tissue anatomy.

RESULTS

We find that five main deep fasciae pathologies are chronic low back pain, chronic neck pain, Dupuytren's disease, plantar fasciitis and iliotibial band syndrome. The corresponding fasciae are respectively the thoracolumbar fascia, the cervical fascia, the palmar fascia, the plantar fascia and the iliotibial tract. Pathological fascia is characterized by increased tissue stiffness along with alterations in myofibroblast activity and the extra-cellular matrix, both in terms of collagen and Matrix Metalloproteases (MMP) levels. Innervation changes such as increased density and sensitization of nociceptive nerve fibers are observed. Additionally, markers of inflammation such as pro-inflammatory cytokines and immune cells are documented. Pain originating from the deep fascia likely results from a combination of increased nerve density, sensitization and chronic nociceptive stimulation, whether physical or chemical.

CONCLUSIONS

The pathological fascia is characterized by changes in innervation, immunology and tissue contracture. Further investigation is required to best benefit both research opportunities and patient care.

Update on the role of molecular factors and fibroblasts in the pathogenesis of Dupuytren's disease

The mechanism by which the fibroblast is able to trigger palmar fibromatosis is still not yet fully understood. It would appear certain that the "abnormal" fibroblasts continuously synthesise profibrotic cytokines which are able to determine the activation to myofibroblasts, to stimulate them to the further proliferation and synthesis of other cytokines, to modify the cells' differentiation and ultrastructural characteristics, as well as the production of matrix and other proteins. Several fibroblast growth factors have been suggested to be responsible of an abnormal cell activation with an aberrantly elevated collagen synthesis and extracellular deposition in Dupuytren's disease, as TGF-Beta, TNF-Alfa, PDGF, GM-CSF, free radicals, metalloproteinases, sex hormones, gene modified expression, mechanical stimulation. The Authors review the current state of knowledge in the field, by analyzing the role of these cytokines in the palmar fibromatosis.

Down-regulation of collagen synthesis and matrix metalloproteinase expression in myofibroblasts from Dupuytren nodule using adenovirus-mediated relaxin gene therapy

Dupuytren's disease is a fibroproliferative connective tissue disorder characterized by contracture of the palmer fascia of the hand. Relaxin (RLN) is a multifunctional factor which contributes to the remodeling of the pelvic ligament by inhibiting fibrosis and inflammatory activities. The aim of this study was to investigate the effect of the RLN gene on the inhibition of fibrosis in myofibroblastic cells. Myofibroblast cells with adenovirus LacZ (Ad-LacZ) as a marker gene or adenovirus relaxin (Ad-RLN) as therapeutic gene showed transgene expressions in beta-galactosidase assay and Western blot analysis. Myofibroblastic cells with Ad-RLN demonstrated a 22% and 48% reduction in collagen I and III mRNA expressions respectively, a 50% decrease in MMP-1, 70% decrease in MMP-2, 80% decrease in MMP-9, and a 15% reduction in MMP-13 protein expression compared with cultures with viral control and saline control. In addition, myofibroblastic cells with Ad-RLN showed a 40% decrease in TIMP 1 and a 15% increase in TIMP 3 protein expression at 48 h compared to cultures with viral control and saline control. Also, myofibroblastic cell with Ad-RLN demonstrated a 74% inhibition of fibronectin and a 52% decrease in total collagen synthesis at 48 h compared with cultures with viral control and saline control. In conclusion, the RLN gene render antifibrogenic effect on myofibroblastic cells from Dupuytren's nodule via direct inhibition of collagen synthesis not through collagenolytic pathway such as MMP-1, -13, TIMP 1, and 3. Therefore relaxin can be an alternative therapeutic strategy in initial stage of Dupuytren's disease by its antifibrogenic effect.

Characterisation of ilomastat for prolonged ocular drug release

We are developing tablet dosage forms for implantation directly into the subconjunctival space of the eye. The matrix metalloproteinase inhibitor, ilomastat, has previously been shown to be efficacious at suppressing scarring following glaucoma filtration surgery (GFS). We report on the physical characterisation of ilomastat which is being developed for ocular implantation. Since ilomastat is being considered for implantation it is necessary to examine its polymorphs and their influence on aspects of the in vitro drug release profile. X-ray powder diffraction identified two polymorphs of ilomastat from different commercial batches of the compound. Tablets were prepared from the two different polymorphs. Isothermal perfusion calorimetry was used to show that amorphous content is not increased during tablet formulation. The melting points of the two polymorphs are 188 and 208°C as determined by differential scanning calorimetry. Utilising single crystal X-ray diffraction, the structural conformations and packing arrangements of the different polymorphs were determined. The orthorhombic crystal crystallised as a monohydrate while the second monoclinic crystal form is non-solvated. Ilomastat tablets prepared from the two different solid forms exhibited similar drug release profiles in vitro under conditions mimicking the aqueous composition, volume and flow of the subconjunctival space after GFS. This suggests that a reproducible dose at each time point during release after implantation should be achievable in vivo with ilomastat tablets prepared from the two polymorphs identified.

Nuclear transport of the serum response factor coactivator MRTF-A is downregulated at tensional homeostasis

The serum response factor (SRF) coactivator myocardin-related transcription factor A (MAL/MKL1/MRTF-A), the nuclear transport and activity of which is regulated by monomeric actin, has been implicated in tension-based regulation of SRF-mediated transcriptional activity. However, the mechanisms involved remain unclear. We used fibroblasts grown within collagen matrices to explore whether MRTF-A transport is regulated by tissue tension. We show that MRTF-A nuclear accumulation following stimulation with serum, actin drugs or acute mechanical stress is prevented within mechanically loaded, anchored matrices at tensional homeostasis. This is accompanied by a higher G/F actin ratio, defective nuclear import and increased cofilin expression. We propose that tension regulates MRTF-A/SRF activity through cofilin-mediated modulation of actin dynamics.

Dupuytren's Disease: Review of the Current Literature

Dupuytren’s disease is one of the most common condition seen by hand surgeons. It is not only prevalent but can also be a most debilitating condition resulting in significant loss of function of the fingers involved. The cause of this disease, however still remains largely unknown although some recent evidence suggests a stem cell etiology. This review article summarizes the current known knowledge of Dupuytren’s as well as the clinical findings, investigations and treatments available.

Molecular mechanisms and treatment strategies for Dupuytren's disease

Dupuytren’s disease (DD) is a common disease of the hand and is characterized by thickening of the palmar fascia and formation of tight collagenous disease cords. At present, the disease is incurable and the molecular pathophysiology of DD is unknown. Surgery remains the most commonly used treatment for DD, but this requires extensive postoperative therapy and is associated with high rates of recurrence. Over the past decades, more indepth exploration of the molecular basis of DD has raised the hopes of developing new treatment modalities. This paper reviews the clinical presentation and molecular pathophysiology of this disease, as well as current and emerging treatment. It also explores the implications of new findings in the laboratory for future treatment.