The inhibition of microRNA-326 by SP1/HDAC1 contributes to proliferation and metastasis of osteosarcoma through promoting SMO expression

Osteosarcoma (OS) is a malignant bone cancer lacking of effective treatment target when the metastasis occurred. This study investigated the implication of MicroRNA-326 in OS proliferation and metastasis to provide the clue for the treatment of metastatic OS. This study knocked down SP1 in MG63 and 143B cells and then performed Microarray assay to find the expression of miRNAs that were influenced by SP1. MTT, EdU, wound-healing and cell invasion assays were performed to evaluated cell proliferation and invasion. OS metastasis to lung was detected in a nude mice model. ChIP assay and DAPA were applied to determine the regulatory effect of SP1 and histone deacetylase 1 (HDAC) complex on miR-326 expression. Human OS tissues showed lowly expressed miR-326 but highly expressed Sp1 and HDAC. Sp1 recruited HDAC1 to miR-326 gene promoter, which caused the histone deacetylation and subsequent transcriptional inhibition of miR-326 gene. miR-326 deficiency induced the stimulation of SMO/Hedgehog pathway and promoted the proliferation and invasion of 143B and MG63 cells as well as the growth and metastasis in nude mice. SP1/HDAC1 caused the transcriptional inhibition of miR-326 gene by promoting histone deacetylation; miR-326 deficiency conversely stimulated SMO/Hedgehog pathway that was responsible for the proliferation and metastasis of OS.

The Impact of Matrix Metalloproteinase-9 on the Sequential Steps of the Metastatic Process

In industrialized countries, cancer is the second leading cause of death after cardiovascular disease. Most cancer patients die because of metastases, which consist of the self-transplantation of malignant cells in anatomical sites other than the one from where the tumor arose. Disseminated cancer cells retain the phenotypic features of the primary tumor, and display very poor differentiation indices and functional regulation. Upon arrival at the target organ, they replace preexisting, normal cells, thereby permanently compromising the patient's health; the metastasis can, in turn, metastasize. The spread of cancer cells implies the degradation of the extracellular matrix by a variety of enzymes, among which the matrix metalloproteinase (MMP)-9 is particularly effective. This article reviews the available published literature concerning the important role that MMP-9 has in the metastatic process. Additionally, information is provided on therapeutic approaches aimed at counteracting, or even preventing, the development of metastasis via the use of MMP-9 antagonists.

Evaluation of genetic polymorphisms in MMP2, MMP9 and MMP20 in Brazilian children with dental fluorosis

Recent studies suggested that genetics contribute to differences in dental fluorosis (DF) susceptibility among individuals having the same environmental exposure. This study evaluated if MMP2, MMP9 and MMP20 are expressed during enamel development and assessed the association between polymorphisms in these genes with DF. Mice susceptible and resistant to DF were used to evaluate if MMPs were candidate genes for DF. The animals received fluoride and their enamels were used for immunohistochemistry. Additionally, 481 subjects from a city with fluoridation of public water supplies were recruited. Genotyping was performed using real time PCR. Allele/genotype frequencies were compared between groups. MMP2, MMP9 and MMP20 immunostaining was detected in both animal groups. DF was observed in 22.4% of the subjects. A borderline association was observed in MMP2 (rs243865), MMP9 (rs17576) and in MMP20 (rs1784418) (p = 0.06, p = 0.08 and p = 0.06 respectively). Briefly, MMPs were expressed during enamel maturation and genetic polymorphisms were not associated with DF.

CD147 as an apoptosis regulator in spermatogenesis: deciphering its association with matrix metalloproteinases' pathway

CD147 plays an important role in germ cells migration and survival/apoptosis during the spermatogenesis process. However, to best of our knowledge, there is no report on the exact role of CD147 gene in the regulation of germ cells apoptosis through matrix metalloproteinases (MMPs). So, the current study aims to evaluate the role of CD147 gene expression in the regulation of germ cells apoptosis in conjunction with MMPs. Real-Time PCR was applied to investigate the expression of CD147, MMP2, MMP7, and MMP9 genes in the azoospermic patients and fertile males. Receiver-operating characteristic curve was used to interpret gene expression data. According to our results, a significant decrease in the expression of CD147 gene and an increase in MMPs genes expression were observed in infertile patients compared to fertile males. These results proved this fact that the CD147 gene has an important role in the regulation of germ cells apoptosis via a MMPs-dependent pathway.

Liver-Selective MMP-9 Inhibition in the Rat Eliminates Ischemia-Reperfusion Injury and Accelerates Liver Regeneration

Recruitment of liver sinusoidal endothelial cell progenitor cells (sprocs) from the bone marrow by vascular endothelial growth factor-stromal cell-derived factor-1 (VEGF-sdf-1) signaling promotes recovery from injury and drives liver regeneration. Matrix metalloproteinases (MMPs) can proteolytically cleave VEGF, which might inhibit progenitor cell recruitment, but systemic matrix metalloproteinase inhibition might prevent efflux of progenitors from the bone marrow. The hypothesis for this study was that liver-selective MMP-9 inhibition would protect the hepatic VEGF-sdf-1 signaling pathway, enhance bone marrow sproc recruitment, and thereby ameliorate liver injury and accelerate liver regeneration, whereas systemic MMP inhibition would impair bone marrow sproc mobilization and therefore have less benefit or be detrimental. We found that liver-selective MMP-9 inhibition accelerated liver regeneration after partial hepatectomy by 40%, whereas systemic MMP inhibition impaired liver regeneration. Liver-selective MMP-9 inhibition largely abolished warm ischemia-reperfusion injury. In the extended hepatectomy model, liver-selective MMP-9 inhibition restored liver sinusoidal endothelial cell integrity, enhanced liver regeneration, and reduced ascites. Liver-selective MMP-9 inhibition markedly increased recruitment and engraftment of bone marrow sprocs, whereas systemic MMP inhibition impaired mobilization of bone marrow sprocs and their hepatic engraftment. Hepatic MMP-9 proteolytically cleaved VEGF after partial hepatectomy. Liver-selective MMP-9 inhibition prevented VEGF cleavage and doubled protein expression of VEGF and its downstream signaling partner sdf-1. In contrast, systemic MMP inhibition enhanced recruitment and engraftment of infused allogeneic progenitors. Conclusion: Liver-selective MMP inhibition prevents proteolytic cleavage of hepatic VEGF, which enhances recruitment and engraftment of bone marrow sprocs after liver injury. This ameliorates injury and accelerates liver regeneration. Liver-selective MMP-9 inhibition may be a therapeutic tool for liver injury that damages the vasculature, whereas systemic MMP inhibition can enhance the benefit of stem cell therapy with endothelial progenitor cells.

Involvement of matrix metalloproteinases (MMP-2, -7, -9) and their tissue inhibitors (TIMP-2, -3) in the regression of chicken postovulatory follicles

The study was undertaken to examine mRNA expression and localization of selected matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), and the activity of MMPs in chicken postovulatory follicles (POFs) during their apoptotic regression. Apoptotic cells and apoptosis-related caspase expression and activity were examined as well. Chickens were sacrificed 2 h and 21 h after ovulation, and five POFs (POF1 to POF5) were isolated from the ovaries. It was found that the number of apoptotic cells (TUNEL-positive) increased along with follicle regression. The relative expression (RQ) of caspase-2, -3, -8 and -9 mRNA increased (P < 0.05) in POF5, while the activity of all examined caspases elevated gradually (approximately 80-150%) reaching the highest level in POF3, and then slowly decreased to the value noted in POF1 (P < 0.05 - P < 0.001). Real-time polymerase chain reaction revealed different expression of MMP-2, -7, -9 and TIMP-2 and -3 on mRNA levels, and activity assay showed the changes in activity of MMP-2 and -9 in the POFs. Regression of the follicles was accompanied predominantly by an increase in the relative expression of MMP-2, and a decrease in TIMP-2 and -3 mRNAs (P < 0.05 - P < 0.001). The activity levels of MMP-2 and -9 showed pronounced changes during the examined period. During follicle regression elevated activity of MMP-2 and -9 was found (P < 0.05 - P < 0.001). Immunohistochemistry demonstrated tissue- and follicle-dependent immunoreactivity of the examined members of the MMP system. In summary, the results showing the apoptotic regression-related changes as well as tissue-dependent differences in the expression of selected MMPs and TIMPs, and activity of MMP-2 and MMP-9, point to the significance that these molecules might participate in the complex orchestration of chicken POF regression.

Ethanol Extract of Lycopodium serratum Thunb. Attenuates Lipopolysaccharide-Induced C6 Glioma Cells Migration via Matrix Metalloproteinase-9 Expression

OBJECTIVE

To elucidate how ethanol extract of L. serratum (ELS) could exert anti-migratory effects on glioma with the suppression of nuclear factor kappa B (NF-κB) downstream pathway.

METHODS

Cell viability of ELS on C6 glioma was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Nitric oxide (NO) assay and 2',7'-dichlorofluorescin diacetate (DCFH-DA) assay were applied to measure NO production and reactive oxygen species (ROS) generation on lipopolysaccharide (LPS)-induced C6 glioma cells. NF-κB, mitogen-activated protein kinase (MAPK), inducible nictric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein were determined by Western blot. Wound healing assay was used to investigate the inhibitory effect of ELS on fetal bovine serum (FBS)-induced migration and matrix metalloproteinase (MMP)-9 and -2 activity was examined by zymography.

RESULTS

ELS suppressed LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 through inhibiting the expression of chemokine CCL2 (or monocyte chemoattractant protein-1, MCP-1). In addition, ELS inhibited the expression of iNOS, COX-2, and the production of NO by LPS in C6 glioma cells. ELS also significantly decreased serum-induced migration of C6 glioma cells in scratch wound healing in a dose-dependent manner (P<0.01). The activity of MMP-9 and -2 were also significantly attenuated by ELS with LPS treatment (P<0.01).

CONCLUSIONS

Our results suggest that downregulation of MMP-9 gene expression might be involved in the anti-migration effect of ELS against LPS-induced C6 glioma cells.

[Neutrophils regulate the process of angiogenesis]

Neutrophils are one of the most abundant leukocytes present in the human blood circulation system, which could provide continuous immune surveillance. Recent studies have shown that neutrophils are closely related to angiogenesis. Neutrophils could release various cytokines, which regulate the angiogenic process by affecting the growth and migration of endothelial cells directly or indirectly. In the present review, the regulatory effects of neutrophils on angiogenic process and mechanisms are analyzed and summarized, which would provide clues for the treatment of related diseases using neutrophils as the targets in the future.

The effect of Epigallocatechin-3-gallate in allergic airway inflammation

BACKGROUND

The variety of beneficial effects of green tea has been reported. Epigallocatechin-3-gallate (EGCG) is a major component of green tea extract. The biological activity of EGCG includes anti-allergic and anti-inflammatory activities. However, the precise effect of EGCG on the allergic airway inflammation has not been fully defined.

METHODOLOGY

In lung tissues of an asthma model-mouse, and nasal epithelial cells of patients with allergic rhinitis, the effect and brief signaling pathway of EGCG on MUC5B expression were investigated using real-time polymerase chain reaction, immunohistochemical, and immunoblot analysis.

RESULTS

In the asthma model-mouse, mucus production, MUC5B expression, p38 mitogen-activated protein kinase (MAPK) and matrix metalloprotease (MMP)-9 expression of the asthma group were significantly higher than in the control group. Extracellular signal related kinase (ERK)1/2 MAPK expression did not change. Mucus production, MUC5B expression, p38 MAPK expression, and MMP-9 expression of the asthma + EGCG group were significantly lower than in the asthma group. In the nasal epithelial cells of patients with allergic rhinitis, EGCG significantly decreased phorbol 12-myristate 13-acetate (PMA)-induced MUC5B and MMP-9 expression.

CONCLUSION

These results suggest that EGCG reduces mucin expression in the asthma model-mouse and nasal epithelial cells of patients with allergic inflammation.

Matrix Metalloproteinase-9 and Synaptic Plasticity in the Central Amygdala in Control of Alcohol-Seeking Behavior

BACKGROUND

Dysfunction of the glutamatergic system has been implicated in alcohol addiction; however, the molecular underpinnings of this phenomenon are still poorly understood. In the current study we have investigated the possible function of matrix metalloproteinase-9 (MMP-9) in alcohol addiction because this protein has recently emerged as an important regulator of excitatory synaptic plasticity.

METHODS

For long-term studies of alcohol drinking in mice we used IntelliCages. Dendritic spines were analyzed using Diolistic staining with DiI. Whole-cell patch clamp was used to assess silent synapses. Motivation for alcohol in human subjects was assessed on the basis of a Semi-Structured Assessment for the Genetics of Alcoholism interview.

RESULTS

Mice devoid of MMP-9 (MMP-9 knockout) drank as much alcohol as wild-type animals; however, they were impaired in alcohol seeking during the motivation test and withdrawal. The deficit could be rescued by overexpression of exogenous MMP-9 in the central nucleus of the amygdala (CeA). Furthermore, the impaired alcohol seeking was associated with structural alterations of dendritic spines in the CeA and, moreover, whole-cell patch clamp analysis of the basal amygdala to CeA projections showed that alcohol consumption and withdrawal were associated with generation of silent synapses. These plastic changes were impaired in MMP-9 knockout mice. Finally, C/T polymorphism of MMP-9 gene at position -1562, which upregulates MMP-9 expression, correlated with increased motivation for alcohol in alcoholics.

CONCLUSIONS

In aggregate, our results indicate a novel mechanism of alcohol craving that involves MMP-9-dependent synaptic plasticity in CeA.

Study on the expression of Toll-like receptor 4 and matrix metalloproteinase-9 in patients with chronic obstructive pulmonary disease and their clinical significance

OBJECTIVE

To investigate the expression of Toll-like receptor 4 (TLR4) and matrix metalloproteinase-9 (MMP-9) in patients with chronic obstructive pulmonary disease (COPD) and their clinical significance.

PATIENTS AND METHODS

Paracancerous tissues from 48 patients with lung squamous cell carcinoma harvested during pulmonary lobectomy were studied. Twenty-four cases of COPD were chosen as the observation group and 24 cases of non-COPD as the control group. The degree of lung inflammation was observed; the ratio of the thickness of the wall to the external diameter of the pulmonary arterioles (WT%), and the ratio of the area of the wall to that of the pulmonary arterioles (WA%) were calculated. Immunohistochemistry was used to evaluate the expression of TLR4, MMP-9, and proliferating cell nuclear antigen (PCNA) in vascular smooth muscle cells, and the expressions were correlated with lung revascularization.

RESULTS

(1) Compared with the non-COPD group, the degree of inflammatory cell infiltration, WA%, and WT% of the COPD group were significantly increased (p<0.05). Additionally, the expression of TLR4, MMP-9, and PCNA in vascular smooth muscle cells was significantly increased (p<0.05). (2) Correlative analysis revealed that the expression of TLR4 and MMP-9 had significant positive correlation with the degree of inflammatory cell infiltration, WA%, WT%, and PCNA expression (p<0.05). Multivariate regression analysis showed that, compared with the smoking index and inflammation score, TLR4 and MMP-9 expression were the strongest factors affecting the parameters of lung revascularization (WA% and WT%) (p<0.05).

CONCLUSIONS

High expression of MMP-9 and TLR4 in patients with COPD may promote inflammatory cell infiltration, induce proliferation of smooth muscle cells, degrade extracellular matrix, and play an important role in lung revascularization.

The role of interleukin 8 and matrix metalloproteinases 2 and 9 in breast cancer treated with tamoxifen

PURPOSE

To evaluate the role of interleukin 8 (IL8) and matrix metalloproteinase (MMP) 2 and 9 as potential parameters of response to adjuvant tamoxifen and to examine possible associations between biomarkers that might imply possible biological dependence.

METHODS

The study included 59 postmenopausal breast cancer patients who received adjuvant tamoxifen. Biomarker levels were determined by ELISA in cytosol tumor extracts.

RESULTS

Estrogen receptor (ER) proved as a reliable parameter of response to tamoxifen; patients with ER+ status had significantly longer median relapse-free survival (RFS) compared to those with ER- status (p=0.04). Patients with IL8-status had longer median RFS compared to those with IL8+ status (77 and 53 months, respectively) but without significant difference. Patients with MMP9+ status had longer median RFS compared to those with MMP9-status (92 and 66 months, respectively) but without significant difference. There was no significant difference in RFS between the subgroups formed according to MMP2 median value. A significant positive correlation was found between IL8 and MMP9 levels (p<0.001). Expression of MMP9 was significantly higher in patients with IL8 levels higher than the median (p=0.001).

CONCLUSIONS

IL8 showed a tendency to act as an unfavorable parameter while MMP9 showed a tendency to act as a favorable parameter of response to tamoxifen, whereas the role of MMP2 as a potential predictive parameter is more complex. The results indicate that possible existence of positive feedback between IL8 and MMP9 might contribute to progression of breast cancer.

The extracellular matrix glycoprotein tenascin-C and matrix metalloproteinases modify cerebellar structural plasticity by exposure to an enriched environment

The importance of the extracellular matrix (ECM) glycoprotein tenascin-C (TnC) and the ECM degrading enzymes, matrix metalloproteinases (MMPs) -2 and -9, in cerebellar histogenesis is well established. This study aimed to examine whether there is a functional relationship between these molecules in regulating structural plasticity of the lateral deep cerebellar nucleus. To this end, starting from postnatal day 21, TnC- or MMP-9-deficient mice were exposed to an enriched environment (EE). We show that 8 weeks of exposure to EE leads to reduced lectin-based staining of perineuronal nets (PNNs), reduction in the size of GABAergic and increase in the number and size of glutamatergic synaptic terminals in wild-type mice. Conversely, TnC-deficient mice showed reduced staining of PNNs compared to wild-type mice maintained under standard conditions, and exposure to EE did not further reduce, but even slightly increased PNN staining. EE did not affect the densities of the two types of synaptic terminals in TnC-deficient mice, while the size of inhibitory, but not excitatory synaptic terminals was increased. In the time frame of 4-8 weeks, MMP-9, but not MMP-2, was observed to influence PNN remodeling and cerebellar synaptic plasticity as revealed by measurement of MMP-9 activity and colocalization with PNNs and synaptic markers. These findings were supported by observations on MMP-9-deficient mice. The present study suggests that TnC contributes to the regulation of structural plasticity in the cerebellum and that interactions between TnC and MMP-9 are likely to be important for these processes to occur.

The effect of granulocyte and granulocyte-macrophage colony stimulating factors on tumor promotion

GM-CSF and G-CSF are capable to regulate the maturation of undifferentiated multipotent stem cells into mature granulocytes, macrophages and T cells in the bone marrow. Thereby, clinicians correct neutropenia induced by chemotherapy or radiation routinely with recombinant G- or GM-CSFs in clinical practice. However, relevant studies found that treatment for cancer patients with adjuvant G-/GM-CSF would occasionally enhance the progression of tumors. Besides, constitutive production of G-CSF or GM-CSF by lung cancer cells could stimulate the growth or the invasion of tumor and result in protecting the tumor against unfavorable environment. These findings convinced researchers that G-/GM-CSF overexpression has a positive effect on malignant tumor progression. The purpose of this article was to explore the most recent research and the mechanisms of GM-CSF and G-CSF-induced tumor promotion and their clinical therapeutic applications.

Role of G protein-coupled estrogen receptor-1 in estradiol 17β-induced alterations in protein synthesis and protein degradation rates in fused bovine satellite cell cultures

In feedlot steers, estradiol-17β (E2) and combined E2 and trenbolone acetate (a testosterone analog) implants enhance rate and efficiency of muscle growth; and, consequently, these compounds are widely used as growth promoters in several countries. Treatment with E2 stimulates protein synthesis rate and suppresses protein degradation rate in fused bovine satellite cell (BSC) cultures; however, the mechanisms involved in these effects are not known with certainty. Although the genomic effects of E2 mediated through the classical estrogen receptors have been characterized, recent studies indicate that binding of E2 to the G protein-coupled estrogen receptor (GPER)-1 mediates nongenomic effects of E2 on cellular function. Our current data show that inhibition of GPER-1, matrix metalloproteinases 2 and 9 (MMP2/9), or heparin binding epidermal growth factor-like growth factor (hbEGF) suppresses E2 stimulate protein synthesis rate in cultured BSCs (P < 0.001) suggesting that all of these are required in order for E2 to stimulate protein synthesis in these cultures. In contrast, inhibition of GPER-1, MMP2/9, or hbEGF has no effect on the ability of E2 to suppress protein degradation rates in fused BSC cultures indicating that these factors are not required in order for E2 to suppress protein degradation rate in these cells. Furthermore, treatment of fused BSC cultures with E2 increased (P < 0.05) pAKT levels indicating that the pAKT pathway may play a role in E2-stimulated effects on cultured BSC. In summary, our current data show that active GPER-1, MMP2/9, and hbEGF are necessary for E2-stimulated protein synthesis but not for E2-simulated suppression of protein degradation in cultured BSC. In addition, E2 treatment increases pAKT levels in cultured BSC.

Venous Hypertension and the Inflammatory Cascade: Major Manifestations and Trigger Mechanisms

Recent histologic and immunocytochemical evidence of venous leg ulcers supports the hypothesis that lesions observed at different stages of chronic venous insufficiency may be associated with, and possibly caused by, an inflammatory process. Evidence has been obtained that venous valve deficiency may be associated with leukocyte infiltration into valve leaflets; therefore, it is hypothesized that an essential event in the inflammatory cascade is the enzymatic degradation of the valve leaflets and venous wall. The metalloproteinases (MMP) in veins exposed to elevated pressures up to 6 weeks were examined in a rat femoral fistula model with venous hypertension. Zymography shows increased activity of pro-MMP-2 at 3 and 6 weeks. MMP-2 and MMP-9 activity was predominantly observed at days 7 and 21 after creation of the fistula. The degree of extracellular matrix remodeling correlates with the morphological finding of macroscopic lesions. Therefore, the MMP-2 and MMP-9 activation is already present in veins days after exposure to elevated blood pressure and coincides with periods of early alterations in the valve morphology and early forms of reflux.

Implication of gelatinases in retinoblastoma development

The aim of this paper was to reveal the latest clinical and research findings regarding the implications of MMP2 and MMP9 matrix metalloproteinases in retinoblastoma development. The targets were finding better options for the therapeutic approach, considering the etiopathogeny and biology of this tumor.

Serum-Induced Differentiation of Glioblastoma Neurospheres Leads to Enhanced Migration/Invasion Capacity That Is Associated with Increased MMP9

Glioblastoma (GBM) is a highly infiltrative brain tumor in which cells with properties of stem cells, called glioblastoma stem cells (GSCs), have been identified. In general, the dominant view is that GSCs are responsible for the initiation, progression, invasion and recurrence of this tumor. In this study, we addressed the question whether the differentiation status of GBM cells is associated with their invasive capacity. For this, several primary GBM cell lines were used, cultured either as neurospheres known to enrich for GSCs or in medium supplemented with 10% FCS that promotes differentiation. The differentiation state of the cells was confirmed by determining the expression of stem cell and differentiation markers. The migration/invasion potential of these cells was tested using in vitro assays and intracranial mouse models. Interestingly, we found that serum-induced differentiation enhanced the invasive potential of GBM cells, which was associated with enhanced MMP9 expression. Chemical inhibition of MMP9 significantly reduced the invasive potential of differentiated cells in vitro. Furthermore, the serum-differentiated cells could revert back to an undifferentiated/stem cell state that were able to form neurospheres, although with a reduced efficiency as compared to non-differentiated counterparts. We propose a model in which activation of the differentiation program in GBM cells enhances their infiltrative potential and that depending on microenvironmental cues a significant portion of these cells are able to revert back to an undifferentiated state with enhanced tumorigenic potential. Thus, effective therapy should target both GSCs and differentiated offspring and targeting of differentiation-associated pathways may offer therapeutic opportunities to reduce invasive growth of GBM.

Matrix Metalloproteinase 9 Exerts Antiviral Activity against Respiratory Syncytial Virus

Increased lung levels of matrix metalloproteinase 9 (MMP9) are frequently observed during respiratory syncytial virus (RSV) infection and elevated MMP9 concentrations are associated with severe disease. However little is known of the functional role of MMP9 during lung infection with RSV. To determine whether MMP9 exerted direct antiviral potential, active MMP9 was incubated with RSV, which showed that MMP9 directly prevented RSV infectivity to airway epithelial cells. Using knockout mice the effect of the loss of Mmp9 expression was examined during RSV infection to demonstrate MMP9’s role in viral clearance and disease progression. Seven days following RSV infection, Mmp9^-/- mice displayed substantial weight loss, increased RSV-induced airway hyperresponsiveness (AHR) and reduced clearance of RSV from the lungs compared to wild type mice. Although total bronchoalveolar lavage fluid (BALF) cell counts were similar in both groups, neutrophil recruitment to the lungs during RSV infection was significantly reduced in Mmp9^-/- mice. Reduced neutrophil recruitment coincided with diminished RANTES, IL-1β, SCF, G-CSF expression and p38 phosphorylation. Induction of p38 signaling was required for RANTES and G-CSF expression during RSV infection in airway epithelial cells. Therefore, MMP9 in RSV lung infection significantly enhances neutrophil recruitment, cytokine production and viral clearance while reducing AHR.

Fucoidan Stimulates Monocyte Migration via ERK/p38 Signaling Pathways and MMP9 Secretion

Critical limb ischemia (CLI) induces the secretion of paracrine signals, leading to monocyte recruitment and thereby contributing to the initiation of angiogenesis and tissue healing. We have previously demonstrated that fucoidan, an antithrombotic polysaccharide, promotes the formation of new blood vessels in a mouse model of hindlimb ischemia. We examined the effect of fucoidan on the capacity of peripheral blood monocytes to adhere and migrate. Monocytes negatively isolated with magnetic beads from peripheral blood of healthy donors were treated with fucoidan. Fucoidan induced a 1.5-fold increase in monocyte adhesion to gelatin (p < 0.05) and a five-fold increase in chemotaxis in Boyden chambers (p < 0.05). Fucoidan also enhanced migration 2.5-fold in a transmigration assay (p < 0.05). MMP9 activity in monocyte supernatants was significantly enhanced by fucoidan (p < 0.05). Finally, Western blot analysis of fucoidan-treated monocytes showed upregulation of ERK/p38 phosphorylation. Inhibition of ERK/p38 phosphorylation abrogated fucoidan enhancement of migration (p < 0.01). Fucoidan displays striking biological effects, notably promoting monocyte adhesion and migration. These effects involve the ERK and p38 pathways, and increased MMP9 activity. Fucoidan could improve critical limb ischemia by promoting monocyte recruitment.

Regulation of high glucose-mediated mucin expression by matrix metalloproteinase-9 in human airway epithelial cells

Mucus hypersecretion is the key manifestation in patients with chronic inflammatory airway diseases and mucin 5AC (MUC5AC) is a major component of airway mucus. Matrix metalloproteinases (MMP)-9, have been found to be involved in the pathogenesis of inflammatory airway diseases. Hyperglycemia has been shown to be an independent risk factor for respiratory infections. We hypothesize that high glucose (HG)-regulates MMP-9 production and MMP-9 activity through nicotinamide adenine dinucleotide phosphate (NADPH)/reactive oxygen species (ROS) cascades pathways, leading to mucin production in human airway epithelial cells (16HBE). We show that HG increases MMP-9 production, MMP-9 activity and MUC5AC expression. These effects are prevented by small interfering RNA (siRNA) for MMP-9, indicating that HG-induced mucin production is MMP-9-dependent. HG activates MMP-9 production, MMP-9 activity and MUC5AC overproduction, which is inhibited by nPG, DMSO and DPI (inhibitors of ROS and NADPH), suggesting that HG-activated mucin synthesis is mediated by NADPH/ROS in 16HBE cells. These observations demonstrate an important role for MMP-9 activated by NADPH/ROS signaling pathways in regulating HG-induced MUC5AC expression. These findings may bring new insights into the molecular pathogenesis of the infections related to diabetes mellitus and lead to novel therapeutic intervention for mucin overproduction in chronic inflammatory airway diseases.

The effect of Epigallocatechin-3-gallate in allergic airway inflammation

BACKGROUND

The variety of beneficial effects of green tea has been reported. Epigallocatechin-3-gallate (EGCG) is a major component of green tea extract. The biological activity of EGCG includes anti-allergic and anti-inflammatory activities. However, the precise effect of EGCG on the allergic airway inflammation has not been fully defined.

METHODOLOGY

In lung tissues of an asthma model-mouse, and nasal epithelial cells of patients with allergic rhinitis, the effect and brief signaling pathway of EGCG on MUC5B expression were investigated using real-time polymerase chain reaction, immunohistochemical, and immunoblot analysis.

RESULTS

In the asthma model-mouse, mucus production, MUC5B expression, p38 mitogen-activated protein kinase (MAPK) and matrix metalloprotease (MMP)-9 expression of the asthma group were significantly higher than in the control group. Extracellular signal related kinase (ERK)1/2 MAPK expression did not change. Mucus production, MUC5B expression, p38 MAPK expression, and MMP-9 expression of the asthma + EGCG group were significantly lower than in the asthma group. In the nasal epithelial cells of patients with allergic rhinitis, EGCG significantly decreased phorbol 12-myristate 13-acetate (PMA)-induced MUC5B and MMP-9 expression.

CONCLUSION

These results suggest that EGCG reduces mucin expression in the asthma model-mouse and nasal epithelial cells of patients with allergic inflammation.

Nerve growth factor metabolic dysfunction in Down's syndrome brains

Basal forebrain cholinergic neurons play a key role in cognition. This neuronal system is highly dependent on NGF for its synaptic integrity and the phenotypic maintenance of its cell bodies. Basal forebrain cholinergic neurons progressively degenerate in Alzheimer's disease and Down's syndrome, and their atrophy contributes to the manifestation of dementia. Paradoxically, in Alzheimer's disease brains, the synthesis of NGF is not affected and there is abundance of the NGF precursor, proNGF. We have shown that this phenomenon is the result of a deficit in NGF's extracellular metabolism that compromises proNGF maturation and exacerbates its subsequent degradation. We hypothesized that a similar imbalance should be present in Down's syndrome. Using a combination of quantitative reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting and zymography, we investigated signs of NGF metabolic dysfunction in post-mortem brains from the temporal (n = 14), frontal (n = 34) and parietal (n = 20) cortex obtained from subjects with Down's syndrome and age-matched controls (age range 31-68 years). We further examined primary cultures of human foetal Down's syndrome cortex (17-21 gestational age weeks) and brains from Ts65Dn mice (12-22 months), a widely used animal model of Down's syndrome. We report a significant increase in proNGF levels in human and mouse Down's syndrome brains, with a concomitant reduction in the levels of plasminogen and tissue plasminogen activator messenger RNA as well as an increment in neuroserpin expression; enzymes that partake in proNGF maturation. Human Down's syndrome brains also exhibited elevated zymogenic activity of MMP9, the major NGF-degrading protease. Our results indicate a failure in NGF precursor maturation in Down's syndrome brains and a likely enhanced proteolytic degradation of NGF, changes which can compromise the trophic support of basal forebrain cholinergic neurons. The alterations in proNGF and MMP9 were also present in cultures of Down's syndrome foetal cortex; suggesting that this trophic compromise may be amenable to rescue, before frank dementia onset. Our study thus provides a novel paradigm for cholinergic neuroprotection in Alzheimer's disease and Down's syndrome.

PSY-1, a Taxus chinensis var. mairei extract, inhibits cancer cell metastasis by interfering with MMPs

Cancer is the most common disease worldwide, with death often occurring as a result of metastasis. Thus, interfering with metastasis has been regarded as a promising strategy to improve the current cancer treatments. However, exploration and development of novel anti-metastatic agents remains a major challenge. Recent evidence indicated that a polysaccharide isolated from Taxus yunnanensis suppressed tumor cells proliferation. With the objective of seeking bioactive extracts, we had previously isolated, purified and characterized a complex, water-soluble polysaccharides, PSY-1, from the leaves of Taxus chinensis var. mairei, and identified its anti-neoplastic effects. In this study, we focused on the effects of PSY-1 on cancer metastasis and its mechanism(s). The results illustrated that PSY-1 effectively suppressed the migration and invasion ability of the melanoma cancer cell line B16-F10, caused down-regulation of MMP-2 and MMP-9, and that the NF-kappaB pathway was involved in the anti-metastatic effects imposed by PSY-1.

Propofol suppresses proliferation, invasion and angiogenesis by down-regulating ERK-VEGF/MMP-9 signaling in Eca-109 esophageal squamous cell carcinoma cells

BACKGROUND AND AIMS

Propofol (2,6-diisopropylphenol), one of the most commonly used intravenous anaesthetic agents during cancer resection surgery, has been reported to have the ability of influencing the invasion of human cancer cells. However, the mechanisms are not very clear. In this study, we investigated the effects of propofol on the proliferation, invasion and angiogenesis of human Eca-109 cells, and explored the mechanism.

METHODS

The human Eca-109 cells was treated with propofol at the concentrations of 10-100 µmol/L for 72 hours or at the concentration of 100 µmol for 8-72 hours. Cell viability was determined by the MTT assay; the effect of propofol on apoptosis by 5'-triphosphate-biotin nick end labeling (TUNEL) staining. The effect of propofol on angiogenesis was determined by the chicken chorioallantoic membrane (CAM) angiogenesis assay. The effect of propofol on cell invasion using a modified Matrigel Boyden chamber assay. ERK1/2, MMP-9 and VEGF leves was detected by western blotting assay.

RESULTS

In human Eca-109 cells, propofol significantly promoted cell apoptosis and inhibited proliferation in a dose and time-dependent manner. Furthermore, propofol inhibited dose and time-dependent invasion and angiogenesis. Propofol significantly dose and time-dependently down-regulated gene expression and protein production of ERK/pERK, VEGF and MMP-9. The functional effects and MMP-9/VEGF inhibition were shown to be dependent on the ERK/VEGF and ERK/MMP-9 signaling pathways. It was noteworthy that the ERK activator (phorbol 12-myristate 13-acetate [PMA]) treatment increased the MMP-9/VEGF levels after propofol treatment, and led to significant increase of proliferation, invasion and angiogenesis.

CONCLUSIONS

These findings indicate that propofol inhibited proliferation, invasion and angiogenesis of human Eca-109 cells in vitro through modulation of ERK-VEGF /MMP-9 signaling. Propofol not only can be an anesthesia agent which reduces pain but plays an important role of inhibiting the migration and angiogenesis of ESCC cells in the therapy of ESCC patients.

S100A4 silencing suppresses proliferation, angiogenesis and invasion of thyroid cancer cells through downregulation of MMP-9 and VEGF

BACKGROUND AND AIM

It is well documented that S100A4 is upregulated in many cancers and plays a pivotal role in tumor proliferation, invasion, metastasis and angiogenesis. However, the precise role and mechanism S100A4 exerts in the thyroid cancer have not been fully elucidated to date. In the present study, we investigated the effect of S100A4 on proliferation, invasion, metastasis and angiogenesis in thyroid cancer cells.

MATERIALS AND METHODS

A plasmid construct was made that expressed full long S100A4 cDNA. The construct was stably transfected into BCPAP and ML-1 thyroid cancer cells (BCPAP/ S100A4 cDNA, ML-1/S100A4 cDNA). S100A4 siRNA was transiently transfected into the DRO cells (DRO/S100A4 siRNA). MMP-9 siRNA or VEGF siRNA was transiently transfected into the BCPAP/ S100A4 cDNA, ML-1/S100A4 cDNA cells (BCPAP/ S100A4 cDNA/VEGF siRNA, ML-1/S100A4 cDNA/ MMP-9 siRNA).

RESULTS

We found that the down-regulation of S100A4 by small interfering RNA decreased cell invasion, metastasis, and angiogenesis by using chicken chorioallantoic membrane (CAM), whereas S100A4 overexpression by cDNA transfection led to increased tumor cell invasion, metastasis, and angiogenesis. Consistent with these results, we found that the down-regulation of S100A4 reduced VEGF and MMP-9 expression. Furthermore, Knockdown of MMP-9 by MMP-9 siRNA inhibited cell invasion and metastasis in the BCPAP/S100A4 cDNA, ML-1/S100A4 cDNA cells. Knockdown of VEGF by VEGF siRNA inhibited cell angiogenesis in the BCPAP/ S100A4 cDNA, ML-1/S100A4 cDNA cells.We also found that downregulation of S100A4 by small interfering RNA resulted in enhanced cell growth inhibition and apoptosis, and vice versa. Our data suggest S100A4 could be an effective approach for the regulation of proliferation, invasion and angiogenesis. Downregulation of S100A4 could inhibit angiogenesis, proliferation and invasion by regulating the expression of MMP-9 and VEGF.

CONCLUSIONS

Our results provide evidence that the downregulation of S100A4 using RNAi technology may provide an effective tool for thyroid cancer therapy.

RNAi-mediated knockdown of relaxin decreases in vitro proliferation and invasiveness of osteosarcoma MG-63 cells by inhibition of MMP-9

PURPOSE

The purpose of this study is to determine the role of relaxin knowdown by siRNA transfection in cellular growth and invasion of osteosarcoma MG-63 cells, and discusses the molecular mechanisms of this action.

MATERIALS AND METHODS

The expression of relaxin in MG-63 cell was examined by western blot or RT-PCR. To evaluate the biological role of relaxin, proliferation assay (MTT) and invasion assay (BD Matrigel™), apoptosis assay (TUNEL and ELISA) and cell cycle analysis (flow cytometer) were performed after silencing relaxin using siRNA. MMP-9 expressions were analyzed using RT-PCR, western blot and zymography after silencing relaxin.

RESULTS

Results showed that the downregulation of relaxin expression by siRNA in human osteosarcoma MG-63 cells significantly inhibited cell proliferation and invasion in vitro. Furthermore, relaxin knockdown led to cell arrest in the G1/G0 phase of the cell cycle, and eventual apoptosis enhancement in MG-63 cells. We provide evidence in our cell model that the relaxin siRNA down-regulated the expression of MMP-9 and the MMP-9 activity, suggesting that relaxin may promote the proliferation, invasion and metastasis of osteosarcoma cells by regulating the expression of MMP-9 and facilitating ECM degradation.

CONCLUSIONS

Therefore, siRNA-directed knockdown of relaxin may represent a viable clinical therapy for osteosarcoma.

Does inhibiting Sur1 complement rt-PA in cerebral ischemia?

Hemorrhagic transformation (HT) associated with recombinant tissue plasminogen activator (rt-PA) complicates and limits its use in stroke. Here, we provide a focused review on the involvement of matrix metalloproteinase 9 (MMP-9) in rt-PA-associated HT in cerebral ischemia, and we review emerging evidence that the selective inhibitor of the sulfonylurea receptor 1 (Sur1), glibenclamide (U.S. adopted name, glyburide), may provide protection against rt-PA-associated HT in cerebral ischemia. Glyburide inhibits activation of MMP-9, ameliorates edema formation, swelling, and symptomatic hemorrhagic transformation, and improves preclinical outcomes in several clinically relevant models of stroke, both without and with rt-PA treatment. A retrospective clinical study comparing outcomes in diabetic patients with stroke treated with rt-PA showed that those who were previously on and were maintained on a sulfonylurea fared significantly better than those whose diabetes was managed without sulfonylureas. Inhibition of Sur1 with injectable glyburide holds promise for ameliorating rt-PA-associated HT in stroke.

MMP-9 increases HER2/neu expression and alters apoptosis levels in human mammary epithelial cells (HMEC)

HER2/neu overexpression leads to poorer prognosis and higher risk of disease reoccurrence in breast cancer patients. The causative factors responsible for increasing HER2/neu expression levels on mammary cells are not known. We investigated whether factors associated with inflammation or metastasis could induce HER2/neu expression on human mammary epithelial cells (HMECs). Human mammary epithelial cells and several human breast cancer cell lines used in our studies were treated with several agents, including estrogen and matrix metalloproteinase-9 (MMP-9), either alone or in various combinations. Relative expression of HER2/neu on the surface of target cells was assessed using fluorochrome-tagged antibodies and a fluorescence cytometer. HER2/neu gene expression was also determined by Western blot analysis and PCR. Apoptosis levels were also determined. MMP-9, administered either alone or in combination with interleukin-7 and estrogen, caused a significant rise in HER2/neu expression on the surface of HMECs. The induction in HER2/neu protein expression was suppressed using a MMP-9 inhibitor. Similar results were obtained for breast cancer cells treated with the estrogen in combination with MMP-9. MMP-9 treatment significantly decreased apoptotic levels in HMECs. Our results indicate that MMP-9 is a regulator of HER2/neu expression on human mammary epithelial cells and suggest that upregulation of HER2/neu by MMP-9 may be relevant to altering the characteristics of normal mammary cells toward a transformed phenotype.

Modification of osteopontin and MMP-9 levels in patients with psoriasis on anti-TNF-α therapy

Psoriasis is a chronic skin inflammatory disease in which a pleiotropic cytokine, tumor necrosis factor alpha (TNF-α), plays a central role, as demonstrated by the clinical success of anti-TNF-α therapy. Among the multiple effects of TNF-α on keratinocytes, the induction of matrix metalloproteinase-9 (MMP-9), a collagenase implicated in joint inflammation, might be one of the key mechanisms in psoriasis pathogenesis. Interestingly, MMP-9 expression can be enhanced also by osteopontin (OPN), a glycosylated protein whose levels are increased in skin and peripheral blood mononuclear cells (PBMC) of psoriasis patients. The aim of the current study is to investigate the relationship between OPN, MMP-9 and TNF-α in psoriasis. Our survey identified high levels of both OPN and MMP-9 in PBMC as well as skin of psoriatic patients with respect to healthy controls. Significant reduction of OPN and MMP-9 levels in PBMC, plasma and lesional skin of psoriasis patients was observed after 24 weeks of anti-TNF-α therapy. Moreover, OPN and MMP-9 were enhanced by TNF-α and down-regulated by anti-TNF-α treatment in healthy PBMC. These findings may suggest that OPN and MMP-9 may be regulated by TNF-α, indicating a possible role in the pathogenesis of psoriasis.

Bone marrow transplantation improves hepatic fibrosis in Abcb4-/- mice via Th1 response and matrix metalloproteinase activity

OBJECTIVE

Reports on the effects of bone marrow-derived cells on hepatic fibrosis are contradictory. Impaired fibrosis but increased inflammation has recently been demonstrated 10 weeks after bone marrow transplantation (BM-Tx) in Abcb4-/- mice. It is hypothesised that BM-Tx might have long-term therapeutic potential by altering the immunological and matrix remodelling processes leading to hepatic regeneration.

METHODS

After lethal irradiation of recipient mice, BM cells from GFP+ donor mice (allogeneic Tx) or Abcb4-/- mice (syngeneic Tx) were transplanted via tail vein injection. Readouts were performed 2, 10 and 20 weeks after Tx. Liver integrity was assessed serologically and histologically. Surrogate markers for fibrogenesis, T helper (Th) response, inflammation, graft-versus-host disease and fibrolysis were analysed by quantitative real-time PCR, zymography and immunohistology.

RESULTS

20 weeks after syngeneic and allogeneic BM-Tx, hepatic grading and staging were significantly improved. In contrast, 2 weeks after BM-Tx inflammatory grading, expression of inflammatory cell markers and associated chemokines and their receptors were increased and subsequently declined. In parallel, CD8+/GFP+ donor-derived T cells infiltrated the liver 2 weeks after BM-Tx. The Th1 cyokine interferon γ was increased 2 and 10 weeks after BM-Tx whereas the Th2 associated interleukin 13 was not altered. The gene expression of matrix metalloproteinases MMP-2, MMP-7, MMP-9 and MMP-13 was transiently upregulated and MMP-9 protein remained elevated 20 weeks after BM-Tx with enhanced gelatinase activity located within the fibrotic areas. Neutrophils were identified as major sources of MMP-9.

CONCLUSION

These results show that BM-Tx causes an antifibrotic Th1 response combined with transient inflammatory effects and subsequently upregulated MMP activity. Antifibrotic Th polarisation and prolonged proteolytic activity, especially of MMP-9, might be responsible for long-term amelioration of hepatic fibrosis.

Role of metalloproteinases and tissue inhibitors of metalloproteinases during cardiopulmonary bypass in rats

Matrix metalloproteinases (MMPs) and the tissue inhibitors of matrix metalloproteinases (TIMPs) regulate matrix remodeling in the heart. Changes in synthesis and release of MMPs and TIMPs are observed after extracorporeal circulation (ECC). Thus, MMPs and TIMPs are supposed to be involved in ECC-mediated cardiac dysfunction. The aim was to examine the role of MMPs and TIMPs in ECC-mediated cardiac dysfunction. Extracorporeal circulation was instituted in rats for 60 min at a flow rate of 120 ml/kg/min. Three groups (n = 10) were studied: group CAO: 60 min ECC without aortic cross-clamping, group CAC: 60 min ECC including 30 min aortic cross-clamping (crystalloid Inzolen(®) cardioplegia), and group CAB: 60 min ECC including 30 min aortic cross-clamping (blood cardioplegia). Left ventricular (LV) function was measured with conductance catheter. Matrix metalloproteinase-activity was determined by zymography and TIMP activity was determined by reverse zymography. Gene expression of MMPs and TIMPs was determined by real-time polymerase chain reaction. Sixty minutes after weaning from bypass, there was a preserved LV function in the CAO and CAB group and an impaired LV function in the CAC group. We observed an increased myocardial activity and an increased myocardial messenger RNA expression of MMP-2, MMP-9, TIMP-1, and TIMP-4 in all ECC groups, when compared with sham animals. With regard to enzyme activity, there was an imbalance of MMP/TIMP ratio leading to an increased activity of MMP in the CAC group. In terms of gene expression, there was an imbalance of MMP-2/TIMP-4 ratio leading to an increased expression of MMP-2 in the CAC group. MMP-2 contributes to myocardial reperfusion injury in this in vivo model of ECC with cardioplegic arrest.

The MMP-9/TIMP-1 axis controls the status of differentiation and function of myelin-forming Schwann cells in nerve regeneration

Background

Myelinating Schwann cells (mSCs) form myelin in the peripheral nervous system. Because of the works by us and others, matrix metalloproteinase-9 (MMP-9) has recently emerged as an essential component of the Schwann cell signaling network during sciatic nerve regeneration.

Methodology/Principal Findings

In the present study, using the genome-wide transcriptional profiling of normal and injured sciatic nerves in mice followed by extensive bioinformatics analyses of the data, we determined that an endogenous, specific MMP-9 inhibitor [tissue inhibitor of metalloproteinases (TIMP)-1] was a top up-regulated gene in the injured nerve. MMP-9 capture followed by gelatin zymography and Western blotting of the isolated samples revealed the presence of the MMP-9/TIMP-1 heterodimers and the activated MMP-9 enzyme in the injured nerve within the first 24 h post-injury. MMP-9 and TIMP-1 co-localized in mSCs. Knockout of the MMP-9 gene in mice resulted in elevated numbers of de-differentiated/immature mSCs in the damaged nerve. Our comparative studies using MMP-9 knockout and wild-type mice documented an aberrantly enhanced proliferative activity and, accordingly, an increased number of post-mitotic Schwann cells, short internodes and additional nodal abnormalities in remyelinated nerves of MMP-9 knockout mice. These data imply that during the first days post-injury MMP-9 exhibits a functionally important anti-mitogenic activity in the wild-type mice. Pharmacological inhibition of MMP activity suppressed the expression of Na_v1.7/1.8 channels in the crushed nerves.

Conclusion/Significance

Collectively, our data established an essential role of the MMP-9/TIMP-1 axis in guiding the mSC differentiation and the molecular assembly of myelin domains in the course of the nerve repair process. Our findings of the MMP-dependent regulation of Na_v channels, which we document here for the first time, provide a basis for therapeutic intervention in sensorimotor pathologies and pain.

[Role of matrix metalloproteinase-9 in the pathogenesis of osteoporosis in patients with chronic obstructive pulmonary disease]

AIM

To determine a relationship between matrix metalloproteinase-9 (MMP-9) activity and its tissue inhibitors TIMP-1 and 2, tumor necrosis factor-alpha (TNF-alpha), bone mineral density (BMD), and bone exchange in chronic obstructive pulmonary disease (COPD).

SUBJECTS AND METHODS

Seventy-six patients with COPD and 20 healthy volunteers were examined using dual-energy X-ray absorptiometry n the lumbar spine (L(II)-L(IV)) and femoral neck (FN). The serum levels of MMP-9, TIMP-1 and TIMP-2, TNF-alpha, and beta-Crosslaps (betaCL) were measured.

RESULTS

There was a higher MMP-9 level in COPD than that in the controls ((383.8 +/- 54.2 and 137.6 +/- 31.4 pg/ml, respectively; p < 0.01). The levels of TIMP-1 and TIMP-2 were not different from those in the control group. An inverse correlation was found between forced expiratory volume in one second (FEV1) and MMP-9 concentration (r = -0.59; p = 0.002) and a positive correlation with smoking index (r = 0.47; p = 0.04). There was an inverse correlation between MMP-9 concentration and BMD in both L(II)-L(IV) and FN (r = -0.67; p < 0.001 and r = -0.61; p < 0.01, respectively) and a direct correlation with betaCL (r = 0.53; p = 0.04). An inverse correlation was established between TNF-alpha and T index in both L(II)-L(IV) (r = -0.54; p < 0.01) and FN (r = -0.48; p < 0.01). At the same time, the level of TNF-alpha directly correlated with the bone resorption marker betaCL (r = 0.53; p = 0.002) and MMP-9 (r = 0.57; p = 0.003).

CONCLUSION

Elevated MMP-9 levels may play an important role in type I collagen degradation, giving rise to enhanced bone resorption in COPD.

New facets of matrix metalloproteinases MMP-2 and MMP-9 as cell surface transducers: outside-in signaling and relationship to tumor progression

This review focuses on matrix metalloproteinases (MMPs)-2 (gelatinase A) and -9 (gelatinase B), both of which are cancer-associated, secreted, zinc-dependent endopeptidases. Gelatinases cleave many different targets (extracellular matrix, cytokines, growth factors, chemokines and cytokine/growth factor receptors) that in turn regulate key signaling pathways in cell growth, migration, invasion, inflammation and angiogenesis. Interactions with cell surface integral membrane proteins (CD44, αVβ/αβ1/αβ2 integrins and Ku protein) can occur through the gelatinases' active site or hemopexin-like C-terminal domain. This review evaluates the recent literature on the non-enzymatic, signal transduction roles of surface-bound gelatinases and their subsequent effects on cell survival, migration and angiogenesis. Gelatinases have long been drug targets. The current status of gelatinase inhibitors as anticancer agents and their failure in the clinic is discussed in light of these new data on the gelatinases' roles as cell surface transducers - data that may lead to the design and development of novel, gelatinase-targeting inhibitors.

Cancer-derived matrix metalloproteinase-9 contributes to tumor tolerance

BACKGROUND AND AIMS

Tumor-specific T regulatory cells (Treg) play a critical role in tumor cell survival. The development of tumor-specific Treg is not fully understood. This study aims to elucidate the role of matrix metalloproteinase (MMP)9 in tumor tolerance development.

METHODS

We recruited 38 patients with laryngeal cancer (LC) in this study. MMP9 levels in the LC were measured by western blotting. Immune cells were isolated from LC tissue for indicated experiments. The cells' activities were characterized by flow cytometry.

RESULTS

High levels of MMP9 were detected in LC that plays a critical role in the development of tolerogenic dendritic cells and LC-specific Tregs. The isolated LC Tregs have the ability to suppress tumor-specific CD8 T cells in a tumor antigen-specific manner.

CONCLUSIONS

This study reveals a novel mechanism in tumor tolerance in which MMP9 plays a critical role in tumor survival. The data imply that MMP9 may be a potential target in the treatment of malignant tumors.

A mechanobiological model of epiphysis structures formation

Developing bone consists of epiphysis, metaphysis and diaphysis. The secondary ossification centre (SOC) appears and grows within the epiphysis, involving two histological stages. Firstly, cartilage canals appear; they carry hypertrophy factors towards the central area of the epiphysis. Canal growth and expansion is modulated by stress on the epiphysis. Secondly, the diffusion of hypertrophy factors causes SOC growth. Hypertrophy is regulated by biological and mechanical factors present within the epiphysis. The finite element method has been used for solving a coupled system of differential equations for modelling these histological stages of epiphyseal development. Cartilage canal spatial-temporal growth patterns were obtained as well as the SOC formation pattern. This model qualitatively agreed with experimental results reported by other authors.

Activation of arterial matrix metalloproteinases leads to vascular calcification in chronic kidney disease

BACKGROUND

The objective of the current study was to determine if altered regulation of matrix metalloproteinases (MMPs) may predispose to extracellular matrix degradation, facilitating arterial calcification in chronic kidney disease (CKD) using a progressive model of CKD-MBD, the Cy/+ rat.

METHODS

Sera were collected from normal or CKD rats at various times and MMP-2 and MMP-9 levels determined by ELISA or zymography. Aorta tissue was harvested at sacrifice for RT-PCR and immunostaining. Calcification of aorta rings was assessed with MMP inhibitors.

RESULTS

There was an increase in MMP-2, MMP-9, TIMP-1, and RUNX-2 expression in the aorta with progressive CKD, and increased MMP-2 activity in the serum. Immunostaining revealed increased expression of MMP-2 and MMP-9 in areas of aorta calcification. There was also an upregulation of MMP-2 and MMP-9 in vascular smooth muscle cells (VSMC) from CKD rats. MMP inhibitors decreased calcification of aorta rings from normal and CKD rats. High phosphorus increased MMP-2 and MMP-9 expressions in VSMC from normal rats but not from CKD rats.

CONCLUSION

MMP-2 and MMP-9 expression and activity are increased with progressive CKD, and blockade of MMP activity can inhibit arterial calcification. These data suggest degradation of the extracellular matrix is a critical step in the pathogenesis of arterial calcification in CKD.

[The role of matrix metalloproteinases in human thymus aging]

The use of immunohistochemical method enabled to obtain for the first time expression ferments of extracellular matrix MMP2 and MMP9 in human thymus. Expression of matrix metalloproteinases is discreased in thymus of old age people in comparison with middle age people. These data testify to the important role of metalloproteinases 2 and 9 in extracellular interaction and proliferation activity in thymus aging.

Matrix metalloproteinase inhibition impairs murine adipose tissue development independently of leptin

Administration of Tolylsam, a MMP inhibitor with relative specificity for gelatinases, at a dose of 100 mg/kg/day to leptin-deficient (ob/ob) mice kept on high fat diet for 15 weeks, was associated with significantly reduced weight gain as compared to controls (p < 0.0005), resulting in lower body weight (p < 0.0005) at the end of the experiments. Food intake, physical activity and body temperature were not affected. Subcutaneous (SC) (2.9 ± 0.1g vs. 3.4 ± 0.2g in controls; p < 0.05) and gonadal (GON) (3.4 ± 0.1g vs. 3.7 ± 0.1g in controls; p = NS) fat mass were reduced by Tolylsam treatment. Reduced MMP-2 (gelatinase A) activity in adipose tissue extracts was confirmed by zymography. Mild adipocyte hypotrophy was observed in treated SC and GON adipose tissues. Blood vessel density was significantly reduced in Tolylsam treated SC (p < 0.05) and GON (p < 0.005) adipose tissues. Sirius red staining revealed comparable collagen content in both SC and GON fat of treated mice, whereas collagen disorganization (ratio thick/thin fibers) was also similar. Thus, gelatinase inhibition in mice with leptin deficiency resulted in lower body and fat pad weights, associated with mild adipocyte hypotrophy. This indicates that MMP inhibition may impair adipose tissue development independently of leptin.

Role of anti-angiogenic factor endostatin in the pathogenesis of experimental ulcerative colitis

AIMS

Vascular endothelial growth factor (VEGF) and pathologic angiogenesis have been demonstrated to play a pathogenic role in the development and progression of inflammatory bowel disease. Thus, we hypothesized that the potent anti-angiogenic factor endostatin might play a beneficial role in experimental ulcerative colitis (UC).

MAIN METHODS

We used three animal models of UC: (1) induced by 6% iodoacetamide (IA) in rats, or (2) by 3% dextran sulfate sodium (DSS) in matrix metalloproteinase-9 (MMP-9) knockout (KO) and wild-type mice, and (3) interleukin-10 (IL-10) KO mice. Groups of MMP-9 KO mice with DSS-induced UC were treated with endostatin or water for 5days.

KEY FINDINGS

We found concomitant upregulation of VEGF, PDGF, MMP-9 and endostatin in both rat and mouse models of UC. A positive correlation between the levels of endostatin or VEGF and the sizes of colonic lesions was seen in IA-induced UC. The levels and activities of MMP-9 were also significantly increased during UC induced by IA and IL-10 KO. Deletion of MMP-9 decreased the levels of endostatin in both water- and DSS-treated MMP-9 KO mice. Treatment with endostatin significantly improved DSS-induced UC in MMP-9 KO mice.

SIGNIFICANCE

1) Concomitantly increased endostatin is a defensive response to the increased VEGF in UC, 2) MMP-9 is a key enzyme to generate endostatin which may modulate the balance between VEGF and endostatin during experimental UC, and 3) endostatin treatment plays a beneficial role in UC. Thus, anti-angiogenesis seems to be a new therapeutic option for UC.

Angiotensin-(1-7) ameliorates myocardial remodeling and interstitial fibrosis in spontaneous hypertension: role of MMPs/TIMPs

Angiotensin-(1-7) displays antihypertensive and antiproliferative properties although its effect on cardiac remodeling and hypertrophy in hypertension has not been fully elucidated. The present study was designed to examine the effect of chronic angiotensin-(1-7) treatment on myocardial remodeling, cardiac hypertrophy and underlying mechanisms in spontaneous hypertension. Adult male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were treated with or without angiotensin-(1-7) or the angiotensin-(1-7) antagonist A-779 for 24 weeks. Mean arterial pressure, left ventricular geometry, expression of the hypertrophic markers ANP and β-MHC, collagen contents (type I and III), collagenase (MMP-1), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of MMPs-1 (TIMP-1) were evaluated in WKY and SHR rats with or without treatment. Our data revealed that chronic angiotensin-(1-7) treatment significantly suppressed hypertension, left ventricular hypertrophy, expression of ANP and β-MHC as well as myocardial fibrosis in SHR rats, the effects of which were nullified by the angiotensin-(1-7) receptor antagonist A-779. In addition, angiotensin-(1-7) treatment significantly counteracted hypertension-induced changes in the mRNA expression of MMP-2 and TIMP-1 and collagenase activity, the effects of which were blunted by A-779. In vitro study revealed that angiotensin-(1-7) directly increased the activity of MMP-2 and MMP-9 while decreasing the content of TIMP-1 and TIMP-2. Taken together, our results revealed a protective effect of angiotensin-(1-7) against cardiac hypertrophy and collagen deposition, which may be related to concerted changes in MMPs and TIMPs levels. These data indicated the therapeutic potential of angiotensin-(1-7) in spontaneous hypertension-induced cardiac remodeling.

Matrix metalloproteinase-9 promotes chronic lymphocytic leukemia b cell survival through its hemopexin domain

Matrix metalloproteinase-9 (MMP-9) is the major MMP produced by B-CLL cells and contributes to their tissue infiltration by degrading extracellular and membrane-anchored substrates. Here we describe a different function for MMP-9 in B-CLL, which involves the hemopexin domain rather than its catalytic function. Binding of soluble or immobilized (pro)MMP-9, a catalytically inactive proMMP-9 mutant, or the MMP-9 hemopexin domain to its docking receptors alpha4beta1 integrin and CD44v, induces an intracellular signaling pathway that prevents B-CLL apoptosis. This pathway is induced in all B-CLL cases, is active in B-CLL lymphoid tissues, and consists of Lyn activation, STAT3 phosphorylation, and Mcl-1 upregulation. Our results establish that MMP/receptor binding induces intracellular survival signals and highlight the role of (pro)MMP-9 in B-CLL pathogenesis.

Interleukin (IL)-23 mediates Toxoplasma gondii-induced immunopathology in the gut via matrixmetalloproteinase-2 and IL-22 but independent of IL-17

Peroral infection with Toxoplasma gondii leads to the development of small intestinal inflammation dependent on Th1 cytokines. The role of Th17 cells in ileitis is unknown. We report interleukin (IL)-23-mediated gelatinase A (matrixmetalloproteinase [MMP]-2) up-regulation in the ileum of infected mice. MMP-2 deficiency as well as therapeutic or prophylactic selective gelatinase blockage protected mice from the development of T. gondii-induced immunopathology. Moreover, IL-23-dependent up-regulation of IL-22 was essential for the development of ileitis, whereas IL-17 was down-regulated and dispensable. CD4(+) T cells were the main source of IL-22 in the small intestinal lamina propria. Thus, IL-23 regulates small intestinal inflammation via IL-22 but independent of IL-17. Gelatinases may be useful targets for treatment of intestinal inflammation.