Prolactin Protects the Structural Integrity of Human Fetal Membranes by Downregulating Inflammation-induced Secretion of Matrix Metalloproteinases.

Prolactin (PRL) is a pleiotropic hormone with a key role in pregnancy. In fetal membranes, PRL can regulate the secretion of pro-inflammatory factors, which induces the activation of matrix metalloproteinases (MMPs). The increase and activation of MMPs deregulate the turnover of the extracellular matrix in the fetal membranes, altering its structure and function, causing premature rupture of the membranes and preterm labor. In this work, we evaluate the effect of PRL upon the secretion of MMP-1, MMP-2, MMP-9, MMP-13, and the tissue inhibitors of metalloproteinases (TIMPs) in human fetal membranes after lipopolysaccharide (LPS) challenge. Nine fetal membranes from healthy non-laboring cesarean deliveries at term were cultured in a 2-independent chamber system and pre-treated with 250, 500, 1000 or 4000 ng/ml of PRL for 24 h, then choriodecidual region was stimulated with 500 ng/ml of LPS plus fresh PRL for 24 h. The MMPs and TIMPs secretion were quantified by ELISA, additionally MMP-2 and MMP-9 gelatinolytic activity was measured by zymography. LPS induced the MMP-9 and MMP-1 secretion, but no MMP-2 or MMP-13 in comparison with basal levels. PRL co-treatment decreased the MMP-2, MMP-9 and MMP-1 secretion induced by LPS. The active forms were present in the tissue extract, showing a response consistent with the secretion profile. TIMP-1 and TIMP-2 secretion was decreased after LPS treatment and the PRL co-treatment reverts this effect. The present results support that PRL may favor the balance between these factors involved in the structural maintenance of fetal membranes in an inflammatory event.

Ski Is Required for Tri-Methylation of H3K9 in Major Satellite and for Repression of Pericentromeric Genes: Mmp3, Mmp10 and Mmp13, in Mouse Fibroblasts.

Several mechanisms directing a rapid transcriptional reactivation of genes immediately after mitosis have been described. However, little is known about the maintenance of repressive signals during mitosis. In this work, we address the role of Ski in the repression of gene expression during M/G1 transition in mouse embryonic fibroblasts (MEFs). We found that Ski localises as a distinct pair of dots at the pericentromeric region of mitotic chromosomes, and the absence of the protein is related to high acetylation and low tri-methylation of H3K9 in pericentromeric major satellite. Moreover, differential expression assays in early G1 cells showed that the presence of Ski is significantly associated with repression of genes localised nearby to pericentromeric DNA. In mitotic cells, chromatin immunoprecipitation assays confirmed the association of Ski to major satellite and the promoters of the most repressed genes: Mmp3, Mmp10 and Mmp13. These genes are at pericentromeric region of chromosome 9. In these promoters, the presence of Ski resulted in increased H3K9 tri-methylation levels. This Ski-dependent regulation is also observed during interphase. Consequently, Mmp activity is augmented in Ski-/- MEFs. Altogether, these data indicate that association of Ski with the pericentromeric region of chromosomes during mitosis is required to maintain the silencing bookmarks of underlying chromatin.

Isolated and combined effects of photobiomodulation therapy, topical nonsteroidal anti-inflammatory drugs, and physical activity in the treatment of osteoarthritis induced by papain.

Osteoarthritis (OA) is a chronic inflammatory disease and is characterized as a degenerative process. This study aimed to evaluate and compare the effects of a topical nonsteroidal anti-inflammatory drug (NSAID), physical activity, and photobiomodulation therapy (PBMT) applied alone and/or in combination between them in an experimental model of knee OA. OA was induced by injection of papain in the knees of rats. After 21 days, the animals started to be treated with the above treatment. Histological analysis shows that the experimental model of OA induction causes morphological changes consistent with the disease, and among treatments, the PBMT is the most effective for reducing these changes. Moreover, the results demonstrate that PBMT and NSAID reduce the total number of cells in the inflammatory infiltrate (p<0.05) and PBMT was the most effective for reducing the activity of myeloperoxidase (p<0.05). Finally, we observed that both NSAID and PBMT were effective for reducing the gene expression of MMP-3 (p<0.05), but in relation to the gene expression of MMP-13, PBMT was the most effective treatment (p<0.05). The results of this study indicate that PBMT is the most effective therapy in stopping disease progression, and improving inflammatory conditions observed in OA.

Co-expression of MMP-14 and MMP-19 predicts poor survival in human glioma.

AIM: Matrix metalloproteinase (MMP)-14 and MMP-19 have been demonstrated to play an important role in the development of human gliomas. However, their prognostic values are not clear. The aim of this study was to investigate whether co-expression of MMP-14 and MMP-19 has prognostic relevance in human gliomas. METHODS: Immunohistochemistry and western blot were used to investigate the expression of MMP-14 and MMP-19 proteins in 128 patients with gliomas. RESULTS: The expression levels of MMP-14 and MMP-19 proteins in glioma tissues were both significantly higher (both P < 0.001) than those in non-neoplastic brain tissues according to the immunohistochemistry analysis, which was confirmed by the western blot analysis. Additionally, the overexpression of either MMP-14 or MMP-19 was significantly associated with the advanced WHO grade (both P = 0.02), the low Karnofsky performance score (KPS) (P = 0.008 and 0.01, respectively) and the poor overall survival (both P = 0.01). Moreover, the Multivariate Cox proportional-hazards regression analysis revealed that the increased expressions of MMP-14 and MMP-19 were both independent prognostic factors for poor overall survival (both P = 0.02). Furthermore, the co-expression of MMP-14 and MMP-19 was additively and more significantly (P = 0.006) associated with adverse prognosis in patients with gliomas than respective expression of MMP-14 and MMP-19. CONCLUSIONS: These findings indicated for the first time that the co-expression of MMP-14 and MMP-19 is significantly correlated with prognosis in glioma patients, suggesting that the co-expression of these proteins may be used as both an early diagnostic and independent prognostic marker.

Matrix metalloproteinase-19 is a key regulator of lung fibrosis in mice and humans.

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by epithelial phenotypic changes and fibroblast activation. Based on the temporal heterogeneity of IPF, we hypothesized that hyperplastic alveolar epithelial cells regulate the fibrotic response. OBJECTIVES: To identify novel mediators of fibrosis comparing the transcriptional signature of hyperplastic epithelial cells and conserved epithelial cells in the same lung. METHODS: Laser capture microscope and microarrays analysis were used to identify differentially expressed genes in IPF lungs. Bleomycin-induced lung fibrosis was evaluated in Mmp19-deficient and wild-type (WT) mice. The role of matrix metalloproteinase (MMP)-19 was additionally studied by transfecting the human MMP19 in alveolar epithelial cells. MEASUREMENTS AND MAIN RESULTS: Laser capture microscope followed by microarray analysis revealed a novel mediator, MMP-19, in hyperplastic epithelial cells adjacent to fibrotic regions. Mmp19(-/-) mice showed a significantly increased lung fibrotic response to bleomycin compared with WT mice. A549 epithelial cells transfected with human MMP19 stimulated wound healing and cell migration, whereas silencing MMP19 had the opposite effect. Gene expression microarray of transfected A549 cells showed that PTGS2 (prostaglandin-endoperoxide synthase 2) was one of the highly induced genes. PTGS2 was overexpressed in IPF lungs and colocalized with MMP-19 in hyperplastic epithelial cells. In WT mice, PTGS2 was significantly increased in bronchoalveolar lavage and lung tissues after bleomycin-induced fibrosis, but not in Mmp19(-/-) mice. Inhibition of Mmp-19 by siRNA resulted in inhibition of Ptgs2 at mRNA and protein levels. CONCLUSIONS: Up-regulation of MMP19 induced by lung injury may play a protective role in the development of fibrosis through the induction of PTGS2.

Localization and hormonal regulation of endometrial matrix metalloproteinase-26 in the rhesus macaque.

BACKGROUND: The current understanding of hormonal regulation of matrix metalloproteinase-26 (MMP-26) in the primate endometrium is incomplete. The goal of this work was to clarify estrogen and progesterone regulation of MMP-26 in the endometrium of ovariectomized, hormone-treated rhesus macaques. METHODS: Ovariectomized rhesus macaques (n= 66) were treated with estradiol (E(2)), E(2) plus progesterone, E(2) followed by progesterone alone or no hormone. Endometrium was collected from the hormone-treated animals during the early, mid- and late proliferative and secretory phases of the artificial menstrual cycle. MMP-26 expression was quantified by real-time PCR, and MMP-26 transcript and protein were localized by in situ hybridization and immunohistochemistry and correlated with estrogen receptor 1 and progesterone receptor (PGR). RESULTS: MMP-26 was localized to glandular epithelium and was undetectable in the endometrial stroma and vasculature. MMP-26 transcript levels were minimal in the hormone-deprived macaques and treatment with E(2) alone did not affect MMP-26 levels. Treatment with progesterone both in the presence and absence of E(2) stimulated MMP-26 expression in the early and mid-secretory phases (P < 0.001). MMP-26 expression preceded decidualization of endometrial stroma. MMP-26 levels then declined to baseline in the late secretory phase (P < 0.01) despite continued E(2) plus progesterone treatment. Loss of detectable MMP-26 expression in the late secretory phase was correlated with late secretory phase loss of glandular epithelial PGR. CONCLUSIONS: Endometrial MMP-26 expression is dependent on the presence of progesterone in the early secretory phase and then gradually becomes refractory to progesterone stimulation in the late secretory phase. In the macaque, MMP-26 is a marker of the pre-decidual, secretory endometrium. During the second half of the late secretory phase, and during decidualization, MMP-26 loses its response to progesterone concurrent with the loss of epithelial PGR. The decline in MMP-26 levels between the mid- and late secretory phases may play a role in the receptive window for embryo implantation.

Brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing the NF-κB pathway in human dermal fibroblasts.

Brazilin (7, 11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol), the major component of Caesalpinia sappan L., is a natural red pigment used for histological staining. Recent studies have shown that brazilin exhibits distinct biological effects, including anti-hepatotoxicity, antiplatelet activity, and anti-inflammatory activities. In the present study, we evaluated the effects of brazilin on MMP-1 and -3 expressions in human dermal fibroblasts exposed to ultraviolet B (UVB) irradiation. Brazilin showed protective effect on UVB-induced loss of cell viability of fibroblasts. Brazilin also blocked significantly UVB-induced Reactive Oxygen Species generation in fibroblasts. Brazilin inhibited UVB-induced MMP-1/3 expressions and secretions in a dose-dependent manner. Moreover, UVB-induced NF-κB activation was completely blocked by treatment with brazilin. These findings suggest that brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing of NF-κB activation in human dermal fibroblasts. Thus, brazilin might be used as a potential agent for treatment of UV-induced skin photoaging.

Immunohistochemical expression of matrix metalloproteinases 1, 2, 7, 9, and 26 in the calcifying cystic odontogenic tumor.

OBJECTIVE: The aim was to evaluate immunoexpression of matrix metalloproteinases (MMPs) 1, 2, 7, 9, and 26 in calcifying cystic odontogenic tumor (CCOT). STUDY DESIGN: Ten cases of CCOT were assessed by immunohistochemical expression of MMPs 1, 2, 7, 9, and 26 in the parenchyma and stroma. Metalloproteinase immunoexpressions and their distribution pattern were semiquantitatively scored. RESULTS: MMPs were expressed in the parenchyma and stroma in all cases of CCOT. Regarding the percentage of immunostained parenchymal cells, MMPs 1, 7, and 9 showed score 2 in 100% of cases. For MMP-2, there was a predominance of score 0 (90%), whereas for MMP-26 immunostaining was varied. CONCLUSIONS: The staining of these metalloproteinases, with the exception of MMP-2, suggests their contribution to tumor growth and expansion. The presence of these metalloproteinases in stromal cells reveals the active participation of these cells in the degradation of the extracellular matrix, contributing to the growth of the tumor studied.

Immunohistochemical expression of matrix metalloproteinases in squamous cell carcinoma of the tongue and lower lip.

OBJECTIVE: To evaluate the immunohistochemical expression of MMP-1, -2, -7, -9 and -26 in oral squamous cell carcinomas (SCCs) according to tumour site and histological grade of malignancy. STUDY DESIGN: Fifteen cases of SCC of the lower lip and 15 cases of tongue SCC were selected and divided into low grade malignancy (n = 17) and high grade malignancy (n = 13). RESULTS: Higher immunohistochemical expression of MMPs by neoplastic cells was observed in tongue SCCs, with a statistically significant difference for MMP-9 (P < 0.05). High-grade SCCs showed a higher expression of MMPs, except for MMP-2, with a statistically significant difference for MMP-7 (P < 0.05) and MMP-26 (P < 0.05). In addition, a direct association was observed between morphological scores of malignancy and MMP immunoreactivity, with the association being significant for MMP-7 and MMP-26. CONCLUSION: The present results demonstrate the important role of MMPs in the development of SCCs of the lower lip and tongue.

Matrilysins may not predict the metastatic potential in squamous cell carcinoma of the tongue.

OBJECTIVE: To examine immunoexpression of matrix metalloproteinase (MMP)-7 and -26 in squamous cell carcinoma (SCC) of the tongue and its relation with cervical metastasis. MATERIAL AND METHODS: Twenty-four cases were selected and divided into two groups: a metastatic group (n = 12) and a non-metastatic group (n = 12). Cases were graded as either negative (score 0), positive (score +) or strongly positive (score ++). RESULTS: MMP-7 expression was identical in both groups, with 17% of the cases graded as score 0, 50% as score + and 33% as score ++. MMP-26 expression was 25% score 0, 8% score + and 67% score ++ in the metastatic group, and 8% score 0, 50% score + and 42% score ++ in the non-metastatic group. Statistical analysis showed no differences between the studied groups and no correlations between proteins. CONCLUSIONS: MMP-7 and -26 immunostaining is not a useful indicator of the metastatic potential of SCCs of the tongue. However, the role of these proteins in the process of invasion and metastasis cannot be ruled out since their more marked presence along the tumor invasion front compared to more central areas of the tumors indicates higher secretion of these proteases in this region, facilitating the invasion process.

Immunohistochemical expression of matrilysins (MMP-7 and MMP-26) in ameloblastomas and adenomatoid odontogenic tumors.

OBJECTIVE: The aim was to evaluate the expression of matrix metalloproteinases (MMPs) 7 and 26 in ameloblastomas and adenomatoid odontogenic tumors (AOTs). STUDY DESIGN: Twenty intraosseous solid ameloblastomas and 10 intraosseous AOTs were evaluated regarding immunohistochemical expression of MMP-7 and -26 in the epithelium and stroma. RESULTS: There was no statistically significant difference in MMP-7 and -26 expression between the epithelium of ameloblastomas (P = .50) and AOTs (P = .90). Stromal staining for MMP-7 was evident in all cases. For MMP-26, stromal staining was observed in 65% of ameloblastomas and 50% of AOTs, and this difference was not statistically significant (P = .69). CONCLUSION: The marked expression of these matrilysins suggests their role in the process of tissue remodeling and growth in the studied tumors, but it does not relate to the their distinct patterns of aggressiveness.

[Extracellular matrix metalloproteases profile identification in chorioamniotic membranes of term and preterm pregnancies through soluble microarrays]. / Identificación del perfil de metaloproteasas de matriz extracelular en membranas corioamnióticas de embarazos a término y pretérmino mediante microarreglos solubles.

BACKGROUND: Physiological and pathological membrane rupture is a complex phenomenon with different biochemical processes; it is known that collagenolitic activity rises and collagen content diminishes within term tissue membranes in comparison to preterm membranes. Identification of these processes within rupture mechanism allows to suggest that fetal membranes and decidua can respond to biochemical and mechanical stimulus alike, and to produce mediators that degrade matrix of intracellular membranes. OBJECTIVE: To identify simultaneously, whit a soluble microarray, different matrix metalloproteinases in extracts from amniochorion of pregnancies at term and preterm. PATIENTS AND METHODS: Biomedical experimental study where amniochorion explants were obtained from four women groups. Group 1: at term with spontaneous labor; group 2: at term without labor; group 3: at term with premature rupture of membranes, and group 4: preterm labor. Explants were cultured for 24 h and then homogenated in their own culture media to obtain cell free extracts. MMP were identified in these extracts using a soluble microarray for MMPs that included: MMP-1, -2, -3, -7, -8, -9, -12 and -13. RESULTS: MMP-8 and -2 were the enzymes most abundant in all the extracts of amniochorion. However, the concentration of MMP-8 in the extracts of group 3 (PROM) was significantly greater in comparison with the extracts of groups 1 and 2 (p = 0.01). The MMP-8 also was in greater concentration in the extracts of group 4 (preterm labor) in comparison with in the extracts of group 1 (p = 0.01). CONCLUSION: Activation of cellular processes that lead to the degradation of connective tissue in the MCA under physiological conditions seems to defer in originating tissues from cases with PROM or preterm labor, and this activation is characterized by an increase in the concentration of MMP-8.

Immunohistochemical expression of MMPs 1, 7, and 26 in syndrome and nonsyndrome odontogenic keratocysts.

OBJECTIVE: The objective of this study was to analyze the expression of matrix metalloproteinases (MMPs) 1, 7, and 26 in odontogenic keratocysts (OKCs) associated with Gorlin syndrome (SOKCs) and nonsyndrome OKCs (NSOKCs). STUDY DESIGN: Twenty-one SOKCs and 20 NSOKCs were evaluated for epithelial expression of MMP-1, MMP-7, and MMP-26 and for mesenchymal expression of MMP-1 by immunohistochemistry. RESULTS: Strong epithelial positivity to MMP-1 was observed in 76% of SOKCs and in 15% of NSOKCs (P < .05). Strong mesenchymal immunoreactivity to MMP-1 was observed in 38% of SOKCs and in 20% of NSOKCs (P > .05). Epithelial immunoreactivity to MMP-7 was strongly positive in 67% of SOKCs and in 40% of NSOKCs (P > .05). For MMP-26, strong positivity was found in 62% of SOKCs, in contrast to 35% of NSOKCs (P > .05). CONCLUSION: MMPs-1, -7 and -26 may play important roles in the biology of OKCs. Furthermore, the presence of these proteases at higher levels in SOKCs may help to explain increased OKC aggressiveness associated with nevoid basal cell carcinoma syndrome.

Identification of a calcium-dependent matrix metalloproteinase complex in rat chorioallantoid membranes during labour.

The induction of the expression of matrix metalloproteinases (MMPs) and their extracellular activation are key processes in connective tissue degradation in the chorioallantoid membrane during rat labour. However, the regulatory mechanisms remain largely unknown. Here, we report the identification of a calcium-dependent high molecular weight complex composed of MMP-9, MMP-3, MMP-2, tissue inhibitor of metalloproteinase 1 (TIMP-1) and TIMP-2, identified by zymography and western blotting. Molecular sieve chromatography confirmed the presence of a complex of MMPs and TIMPs with an exclusion volume >670 kDa. Differential scanning calorimetry of the complex confirmed the existence of a macromolecular complex that unfolds with a broad transition; it is denatured over a wide range of temperatures and has a T(m) of 72 degrees C in the presence of Ca(2+). When denatured in the absence of Ca(2+), there were at least eight transitions with T(m)s that corresponded to pro-MMP-9, MMP-9, pro-MMP-3, MMP-3, pro-MMP-2, MMP-2, TIMP-1 and TIMP-2. Co-localization of the same molecular components was demonstrated by confocal microscopy using cell-depleted chorioallantoid membranes. The assembly and disassembly of the complex can be reproduced at physiological concentrations of Ca(2+). This complex provides a potential mechanism for the enzymatic regulation of MMPs, which may participate in connective tissue degradation leading to the rupture of the fetal membranes during labour.

Tissue mRNA expression in rat of newly described matrix metalloproteinases.

Matrix metalloproteinases (MMPs) comprise a large group of endoproteinases that degrade all protein components of the extracellular matrix. Functionally, MMPs contribute to several different physiological as well as pathological conditions. The number of newly described MMPs has increased in recent years, although current knowledge about their expression pattern in various tissues remains incomplete. Here we analyzed the relative mRNA expression of the most recently described MMPs--MT5-MMP (MMP-24), MT6-MMP (MMP-25), MMP-27 and epilysin (MMP-28)--in a broad selection of rat tissues using real time-PCR. MMP-24 mRNA was found to be widely expressed with predominance in the central nervous system. MMP-25 mRNA, in contrast, exhibited peak expression levels in testis, kidney and skeletal muscle, differing from previously described distribution patterns in humans. mRNAs for MMP-27 and MMP-28 were generally expressed at a lower level. All four MMPs studied were detected at higher mRNA levels in bone and kidney, suggesting a possible role of these MMPs in physiological processes within these two organs. The present study highlights the differential distribution pattern of newly described MMPs among different tissues and underlines differences in the mRNA expression between different species.