A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is unclear.Ultrasound targeted microbubble destruction mediated gene transfection is a new method to overexpress genes.AIM To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of HCC.METHODS In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,respectively.In addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell behavior.Next,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and EMT.In vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation ability.RESULTS We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of UTMBs.Additionally,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of TIMP2.And miR-873-5p mimic counteracted the impact of HAND2-AS1.Further,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to UTMBs.We discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/MMP9.In vivo results showed that HAND2-AS1 silencing significantly inhibited tumor formation in mice.CONCLUSION LncRNA HAND2-AS1 promotes TIMP2 expression by targeting miR-873-5p to inhibit HepG2 cell growth and delay HCC progression.

Suppression of matrix metalloproteinase-2 via RNA interference inhibits pancreatic carcinoma cell invasiveness and adhesion

AIM:To investigate the inhibitory effects of RNA interference (RNAi) on expression of matrix metalloproteinase-2 (MMP-2) gene and invasiveness and adhesion of human pancreatic cancer cell line,BxPC-3.METHODS:RNAi was performed using the vector (pGPU6)-based small interference RNA (siRNA) plasmid gene silence system to specifically knock down MMP-2 expression in pancreatic cancer cell line,BxPC-3. Four groups of different specific target sequence in coding region of MMP-2 and one non-specific sequence were chosen to construct four experimental siRNA plasmids of pGPU6-1,pGPU6-2,pGPU6-3 and pGPU6-4,and one negative control siRNA plasmid of pGPU6 (-). MMP-2 expression was measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Cell proliferation and apoptosis were examined by methyl thiazolyl tetrazolium (MTT) and flow cytometry,respectively. The abilities of adhesion and invasion were detected by cell adhesion assay and cell invasion assay using Transwell chambers.RESULTS:The expression of MMP-2 was inhibited and the inhibitory effects of different sequence varied. pGPU6-1 group had the most efficient inhibitory effect,followed by pGPU6-2 and pGPU6-3 groups.Invasiveness and adhesion were more significantly reduced in pGPU6-1,pGPU6-2 and pGPU6-3 groups as compared with pGPU6 (-) and blank control groups. However,no difference concerning cell proliferation and apoptosis was observed after transfection between experiment groups and control groups.CONCLUSION:RNAi against MMP-2 successfully inhibited the mRNA and protein expression of MMP-2 in the pancreatic cancer cell line,BxPC-3,leading to a potent suppression of tumor cell adhesion and invasion without affecting cell proliferation and apoptosis. These findings suggest that the RNAi approach towards MMP-2 may be an effective therapeutic strategy for the clinical management of pancreatic tumor.

Relationship between matrix metalloproteinase-2 mRNA expression and clinicopathological and urokinase-type plasminogen activator system parameters and prognosis in human gastric cancer

AIM: To investigate the relationship between matrix metalloproteinase-2 (MMP-2) mRNA expression and clinicopathologic and urokinase-type plasminogen activator (uPA) system parameter and prognosis in human gastric cancer. METHODS: Expression of MMP-2 mRNA, uPA, and uPA-R mRNA in tumor tissues and ≥5 cm adjacent normal tissues from 67 cases of gastric cancer was studied using RT-PCR and Northern blot respectively.Survival analyses were done using the Kaplan-Meier method. RESULTS: The expression rates of MMP-2 mRNA,uPA and uPA-R mRNA in tumor tissues (31%,41%,and 51%, respectively) were significantly higher than those in ≥5 cm adjacent tissues (19%, 11%, and 9%; X2=4.59,43.58, and 53.24 respectively, P<0.05,0.0001,and 0.0001, respectively). Expression of MMP-2 mRNA was significantly correlated with lymph node metastasis (metastasis: 61.9%, no metastasis: 39.1%, X2= 7.61, P<0.05),Lauren's classification of diffuse/mixed types:54.2%,intestinal type: 26.3%,X2 = 4.25, P<0.05, expression of uPA and uPA-R mRNA (uPA+: 55.1%, uPA-: 22.2% and uPA-R+: 54.9%, uPA-R-: 18.8%, X2=5.72 and 6.40 respectively, P<0.05).Kaplan-Meier survival analysis of MMP-2 mRNA expression did not show significant difference in all 67 cases, but revealed an association of the expression of MMP-2 mRNA, uPA, and uPA-R mRNA with worse prognosis (P= 0.0083, 0.0160, and 0.0094, respectively). CONCLUSION: MMP-2 may play an important role in the development of invasion and metastasis of gastric cancer.

Correlation of RECK with Matrix Metalloproteinase-2 in Regulation of Trophoblast Invasion of Early Pregnancy

To study the role of the reversion-inducing-cysteine-rich protein with Kazal motifs （RECK） gene and matrix metalloproteinase-2 （MMP-2） in the regulation of trophoblast invasion of early pregnancy. Immunohistochemistry, Western blot and gelatin zymography were used to detect the RECK protein expression localization, expression level and MMP-2 activation level in the placental tissues harvested from 52 normal pregnant women （27 in the early pregnancy, 25 in the term pregnancy）. Immunohistochemistry showed that RECK expression was found both in villous tissues of early pregnancy group and term pregnancy group and was mainly observed in cell membrane and cytoplasm of cytotrophoblasts and syneytiotrophoblasts. RECK expression increased with gestational time. RECK expression of early pregnancy group was significantly lower than that of term pregnancy group （P〈0.05）. RECK expression was significantly lower in cellular column （CC） with invasion ability. Western blot showed that the RECK protein expression in early pregnancy group was significantly lower than that in term pregnancy （P〈0.05）. The optical density values of RECK protein expression in early pregnancy group and term pregnancy group were 1.35±0.14 and 2.68±0.26, respectively, while MMP-2 activation ratio was contrary to RECK protein expression and decreased with the gestation time （P〈0.01）. The MMP-2 activation ratios of early pregnancy group and term pregnancy group were 0.46±0.05 and 0.10±0.02, respectively. The expression of the tumor inhibitory gene RECK was positively related with the invasion ability of trophoblasts, while the invasion gene MMP-2 was negatively related with the ability. The interaction between RECK and MMP-2 may play an important role in the regulation of the trophoblast invasion in early pregnancy.

Recent progress in ternary mixed matrix membranes for CO_(2) separation

Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,such as the presence of interfacial voids,hardening of polymer chains,and blockage of micropores by polymers between common MMMsfillers and the polymer matrix,currently limit the gas sep-aration performance of MMMs.Ternary phase MMMs(consisting of afiller,an additive,and a matrix)made by adding a third compound,usually functionalized additives,can overcome the structural problems of binary phase MMMs and positively impact membrane separation performance.This review introduces the structure and fabrication processes for ternary MMMs,categorizes various nanofillers and the third component,and summarizes and analyzes in detail the CO_(2) separation performance of newly developed ternary MMMs based on both rubbery and glassy polymers.Based on this separation data,the challenges of ternary MMMs are also discussed.Finally,future directions for ternary MMMs are proposed.

Distribution and relative activity of matrix metalloproteinase-2 in human coronal dentin

The presence of matrix metalloproteinase-2 （MMP-2） in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determine the MMP-2 distribution and relative activity in demineralized dentin. Crowns of twenty eight human molars were sectioned into inner （ID）, middle （MD）, and outer dentin （OD） regions and demineralized. MMP-2 was extracted with 0.33 mol·L-1 EDTA/2 mol·L-1 guanidine-HCl, pH 7.4, and MMP-2 concentration was estimated with enzyme-linked immunoabsorbant assay （ELISA）. Further characterization was accomplished by Western blotting analysis and gelatin zymography. The mean concentrations of MMP-2 per mg dentin protein in the dentin regions were significantly different （P=0.043）： 0.9 ng （ID）, 0.4 ng （MD）, and 2.2 ng （OD）, respectively. The pattern of MMP-2 concentration was OD〉ID〉MD. Western blotting analysis detected -66 and -72 kDa immunopositive proteins corresponding to pro- and mature MMP-2, respectively, in the ID and MD, and a -66 kDa protein in the OD. Gelatinolytic activity consistent with MMP-2 was detected in all regions. Interestingly, the pattern of levels of Western blot immunodetection and gelatinolytic activity was MD〉ID〉OD. The eoneentration of MMP-2 in human coronal dentin was highest in the region of dentin that contains the dentinoenamel junction and least in the middle region of dentin. However, levels of Western blot immunodetection and gelatinolytic activity did not correlate with the estimated regional concentrations of MMP-2, potentially indicating region specific protein interactions.

Vascular Endothelial Growth Factorl65-regulated Nasopharyngeal Carcinoma Cell Lines Invasion and Migration Involve Expression and Activation of Matrix Metalloproteinase-2

The effect of vascular endothelial growth factor （VEGF） overexpression on matrix metalloproteinase-2 （MMP-2） in nasopharyngeal carcinoma （NPC） cells in vitro and the possible mechanism involved were investigated, and the correlation between the expression of VEGF and MMP-2 in NPC evaluated. The NPC cells were transfected with PAd-trackVEGF165 plasmid. The expression levels of VEGF and MMP-2 mRNA and protein in NPC cells were detected by semi-quantitative RT-PCR and Western blot respectively. It was found that the expression of VEGF and MMP-2 mRNA and protein was significantly increased in NPC cells after transfection of VEGF 165. It was concluded that the expression of VEGF was correlated to the in vitro invasion of NPC cells, and the induction of MMP-2 by VEGF was a key process of NPC cell invasion.

Matrix metalloproteinase-9-1562C>T polymorphism may increase the risk of lymphatic metastasis of colorectal cancer

AIM. To explore the role of the matrix metalloproteinase-9 （MMP-9） polymorphism in colorectal cancer （CRC） in a northeast Chinese population.METHODS： Genotyping of MNP-9-1562C〉T and 279R〉Q polymorphisms was carried out on blood samples from 137 colorectal cancer patients and 199 controls using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. Multivariate logistic regression models were used to calculate adjusted odds ratios （OR） and 95% confidence intervals （95% CI）.RESULTS： The distribution of IVllVlP-9 -2562C〉T and 279 R〉Q genotype was not significantly associated with the risk of CRC. However, the risk of Ilymph node metastasis of CRC was increased in patients with the -1562T allele （OR = 2.601; 95% CI = 1.160-5.835; P = 0.022）. The frequency of MMP-9 279RR ＋ RQ genotype was higher than the QQ genotype among CRC patients younger than sixty years old （OR = 0.102, 95% CI = 0.013-0.812; P = 0.012）.CONCLUSION： Our results indicated that the MMP-9- 1562C〉T polymorphism affects lymph node metastasis of CRC. In addition, the MMP-9 279R allele may lead to a younger age of onset of colorectal cancer.

Expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic stellate cells during rat hepatic fibrosis and its intervention by IL-10

AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibrosis was induced by CCI4 administration and 60 male Sprague-Dawley rats were randomly divided into normal control group (group N, 8 rats), CCI4-induced group (group C, 28 rats) and IL-10-treated group (group I, 24 rats). At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type IV collagenase through portal vein catheter and the suspension was centrifuged by 11% Nycodenz density gradient to isolate hepatic stellate cells (HSCs). RT-PCR was used to analyze mRNA of MMP-2 and TIMP-1 from freshly isolated cells. Densitometric data were standardized with β-actin signals. Immunocytochemistry was performed to detect MMP-2 and TIMP-1 expression in HSC cultured for 72 h. RESULTS: Compared to group N in the 7th wk, MMP-2 and TIMP-1 mRNA increased in group C (P= 0.001/0.001) and group I (P= 0.001/0.009). The level of MMP-2 and TIMP-1 mRNA in group I was significantly lower than that in group C (P= 0.001/0.001). In the 11th wk, MMP-2 mRNA in group I was still lower than that in group C (P = 0.005), but both dropped compared with that in the 7th week (P = 0.001/0.004). TIMP-1 mRNA in group I was still lower than that in group C (P= 0.001), and increased in group C (P= 0.001) while decreased in group I (P = 0.042) compared with that in the 7th wk. Same results were found by immunocytochemistry. CONCLUSION: Expression of MMP-2 and TIMP-1 is increased in hepatic fibrosis. IL-10 exhibits an antifibrogenic effect by suppressing MMP-2 and TIMP-1 expression.

Expressions of cyclooxygenase-2 and matrix metalloproteinase-9 in cervical carcinoma and their clinical significance

Objective: To investigate the expressions of cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 in cervical carcinoma and their clinical significance. Methods: Immunohistochemistry SP method was used to detect the expres- sions of COX-2 and MMP-9 in 72 cases of invasive carcinoma of cervix (ICC) and 16 cases of normal cervical epithelium remote from tumor (NCE). The relationships between the expressions of COX-2, MMP-9 in ICC and some characteristics relating to clinical pathology of cervical carcinoma such as histological grading, lymph node metastasis, stromal invasion and FIGO stage were analyzed statistically. Results: The rates of the positive expressions of COX-2 and MMP-9 in ICC were significantly higher than those in NCE. COX-2: 88.9% (64/72) in group ICC and 12.5% (2/16) in group NCE, P = 0.000; MMP-9: 94.4% (68/72) in group ICC and 43.8% (7/16) in group NCE, P = 0.000. The expression of COX-2 was positively correlated with lymph node metastasis (r = 0.296, P = 0.012) and stromal invasion (r = 0.257, P = 0.029). The expression of MMP-9 was positively correlated with FIGO stage (r = 0.329, P = 0.005) and histological grading (r = 0.351, P = 0.003). The expression of COX-2 was positively correlated with the expression of MMP-9 in ICC (r = 0.297, P = 0.011). Conclusion: The overexpressions of COX-2 and MMP-9 were closely related to the invasion and growth of cervical carcinoma. The tissue with the overexpression of COX-2 had strong invasion ability. COX-2 and MMP-9 had synergistic effect on proliferation, invasion and metastasis of cancer cells. Detecting the coexpression of COX-2 and MMP-9 may be of value in further understanding the biological behavior and predicting the prognosis of cervical carcinoma.

Do different bariatric surgical procedures influence plasma levels of matrix metalloproteinase-2,-7,and-9 among patients with type 2 diabetes mellitus?

BACKGROUND Bariatric surgery is an efficient strategy for body weight and type 2 diabetes mellitus(T2 DM) management. Abnormal lipid deposition in visceral organs,especially the pancreas and liver, might cause beta-cell dysfunction and insulin resistance. Extracellular matrix(ECM) remodeling allows adipose expansion, and matrix metalloproteinases(MMPs) play essential roles in ECM construction.MMP-2 and MMP-9 are the substrates of MMP-7. Different studies have reported that MMP-2,-7, and-9 increase in patients with obesity and metabolic syndromes or T2 DM and are considered biomarkers in obesity and hyperglycemia patients.AIMTo prospectively investigate whether MMP-2, MMP-7, and MMP-9 differ after two bariatric surgeries: Gastric bypass(GB) and sleeve gastrectomy(SG).METHODS We performed GB in 23 and SG in 19 obese patients with T2 DM. We measured body weight, waist circumference, body mass index(BMI), and serum concentrations of total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fasting blood sugar(FBS),hemoglobin A1 c(Hb A1 c), C-peptide, homeostasis model assessments of insulin resistance, and MMP-2, MMP-7, and MMP-9 levels at baseline and at 3, 12, and 24 mo post-operation.RESULTS Twenty-three patients aged 44.7 ± 9.7 years underwent GB, and 19 patients aged40.1 ± 9.1 years underwent SG. In the GB group, BMI decreased from 30.3 ± 3.4 to24.4 ± 2.4 kg/m2, Hb A1 c decreased from 9.2% ± 1.5% to 6.7% ± 1.4%, and FBS decreased from 171.6 ± 65.0 mg/d L to 117.7 ± 37.5 mg/d L 2 years post-operation(P < 0.001). However, the MMP-2, MMP-7, and MMP-9 levels pre-and post-GB were similar even 2 years post-operation(P = 0.107, 0.258, and 0.466,respectively). The SG group revealed similar results: BMI decreased from 36.2 ±5.1 to 26.9 ± 4.7 kg/m2, Hb A1 c decreased from 7.9% ± 1.7% to 5.8% ± 0.6%, and FBS decreased from 138.3 ± 55.6 mg/d L to 95.1 ± 3.1 mg/d L(P < 0.001). The serum MMP-2,-7, and-9 levels pre-and post-SG were not different(P = 0.083,0.869, and 0.1, respectively).CONCLUSION Improvements in obesity and T2 DM induced by bariatric surgery might be the result of MMP-2,-7, or-9 independent pathways.

Methanol extract of Codium fragile inhibits tumor necrosis factor-ɑ-induced matrix metalloproteinase-9 and invasiveness of MDA-MB-231 cells by suppressing nuclear factor-κB activation

Objective:To evaluate whether the methanol extract of Codium fragile(MECF) regulates tumor necrosis factor-α(TNF-α)-induced invasion of human breast cancer MDA-MB-231 cells by suppressing matrix metalloproteinase-9(MMP-9).Methods:Reverse transcriptionpolymerase chain reaction(RT-PCR) and western blot analysis were performed to analyze the expression of MMP-9 and nuclear factor-κB(NF-κB) subunits,p65 and p50,and IκB in MDA-MB-231 cells.3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide(MTT) assay was used for cell viability.MMP-9 activity and invasion were measured by gelatin zymography and a matrigel invasion assay,respectively.NF- κB activity was measured by an electrophoretic mobility shift assay and luciferase activity.Results:MECF had no effects on cell viability up to a concentration of 100 μg/mL in human breast cancer MDA-MB-231 cells regardless of the presence of TNF-α.MDA-MB-231 cells that were stimulated with TNF-α showed a marked increase of invasion compared to the untreated control,whereas pretreatment with MECF downregulated the TNF-α-induced invasion of MDA-MB-231 cells.Additionally,zymography,western blot analysis,and reverse transcriptase-polymerase chain reaction(RT-PCR) confirmed that MECF decreased TNF-α-induced MMP-9 expression and activity which is a key regulator for cancer invasion.According to an electrophoretic morbidity shift assay,pretreatment with MECF in MDA-MB-231 cells significantly decreased the TNF-α-induced DNA-binding activity of nuclear factor- κB(NF- κB),which is an important transcription factor for regulating cancer invasion-related genes such as MMP-9.Furthermore,treatment with MECF sustained the expression of p65 and p50 in response to TNF-α in the cytosolic compartment.The luciferase assay demonstrated that MECF attenuated TNF-α-induced NF- κB luciferase activity.Conclusion:MECF exhibited its antiinvasive capability by downregulating TNF-α-induced MMP-9 expression,resulting from the suppression of NF- κB activity in the human breast cancer cell line MDA-MB-231.

Effects of hypoxia,hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 in hepatic stellate cells

AIM: To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells (HSC). METHODS: The expressions of MMP-2, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and membrane type matrix metalloproteinase-1 (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supernatant was revealed by zymography. RESULTS: In the situation of hypoxia for 12h, the expression of MMP-2 protein was enhanced (hypoxia group positive indexes: 5.7 +/- 2.0, n=10; control: 3.2 +/- 1.0, n = 7; P【0.05), while TIMP-2 protein was decreased in HSC (hypoxia group positive indexes: 2.5 +/- 0.7, n = 10; control: 3.6 +/- 1.0, n = 7; P 【 0.05), and the activity (total A) of MMP-2 in supernatant declined obviously (hypoxia group: 7.334 +/- 1.922, n = 9; control: 17.277 +/- 7.424, n = 11; P 【 0.01). Compared the varied duration of hypoxia, the changes of expressions including mRNA and protein level as well as activity of MMP-2 were most notable in 6h group. The highest value(A(hypoxia)-A(control)) of the protein and the most intense signal of mRNA were in the period of hypoxia for 6h, along with the lowest activity of MMP-2. In the situation of hyperoxia for 12h, the contents (A(450)) of MMP-2 and TIMP-2 in supernatant were both higher than those in the control, especially the TIMP-2 (hyperoxia group: 0.0499 +/- 0.0144, n = 16; control: 0.0219 +/- 0.0098, n = 14; P 【 0.01), and so was the activity of MMP-2 (hyperoxia group: 5.252 +/- 0.771, n = 14; control: 4.304 +/- 1.083, n = 12; P 【 0.05), and the expression of MT1-MMP was increased. CONCLUSION: HSC is sensitive to the oxygen, hypoxia enhances the expression of MMP-2 and the effect is more marked at the early stage; hyperoxia mainly raises the activity of MMP-2.

Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were collected.Fourteen SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic regression.The multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)modeling.Results Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 rs1053605.Carriers of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased risk.CCL2 rs4586 and MMP-2 rs14070 exhibited the most significant interactions.Conclusion CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

A nonwoven supported mixed matrix membrane for CH4/N2 separation

Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions.This study focuses on modifying the overall performance of CH_(4)/N_(2)separation membranes.A novel mixed matrix membrane(MMM)with a reinforced substrate structure was developed through a straightforward dip-coating technique.This MMM incorporates a polytetrafluoroethylene(PTFE)porous membrane as the supporting framework,while a composite of block polymer(styrene-butadiene-styrene)and metal-organic framework(Ni-MOF-74)forms the selective separation layer.Comprehensive characterization of Ni-MOF-74 and the fabricatedmembranes was conducted using X-rays diffraction,scanning electron microscope,Brunauer-Emmett-Teller analysis,and gas permeance tests.The findings indicate a robust integration of the PTFE porous support with the membrane layer,enhancing the mechanical stability of theMMM.Under optimal conditions,the mechanical strength of the PM20 membrane(containing 20%Ni-MOF-74)was observed to be 37.7 MPa,representing remarkable increase compared to the non-reinforcedMMM.Additionally,thePM20membrane exhibited an impressive CH4 permeation rate of 92 barrer(1 barrer﹦3.35×10^(-16)mol·m·m^(-2)·s^(-1)·Pa^(-1))alongside a CH_(4)/N_(2)selectivity of 4.18.These results underscore the MMM's substantial performance and its promising potential in methane enrichment applications.

Immunohistochemical Studies of the Expression of Matrix Metalloproteinase-2 and Metalloproteinase-9 in Human Prostate Cancer

To study the expression of matrix metalloproteinase 2 and 9 in human prostate cancer, matrix metalloproteinase 2 and 9 were immunohistochemically detected in tissues of prostate cancer and benign prostatic hyperplasia (BPH). Our results showed that matrix metalloproteinase 2 and 9 levels in prostate cancer were much higher than those in tissues of BPH, with the cancer invasion being positively correlated with the expression of the metalloproteinases. It is concluded that matrix metalloproteinase 2 and 9 are better molecular markers, which are of help in the diagnosis and prediction of prognosis of prostate cancer.

Rosiglitazone uppresses lipopolysaccharide-induced matrix metalloproteinase-2 activity in rat aortic endothelial cells via rasMEK1/2 signaling

ix metalloproteinase(MMPs) plays a key role in the pathogenesis of chronic inflammatory disease,such as atherosclerosis.Among MMPs,MMP-2 is regarded as a major proteinase in atherosclerotic plaque lesions.Peroxisome proliferator activated receptor-gamma(PPARg) ameliorates oxidative stress and the inflammatory response.The aim of the present study was to evaluate the effect of Rosiglitazone on Lipopolysaccharide(LPS)-induced MMP-2 activation as well as its possible mechanism.LPS-induced MMP-2 activity was inhibited by Rosiglitazone(PPARg agonist) in the rat aortic endothelial cells(RAEC).LPS-induced MMP-2 activation was diminished no matter exposure to NF-kB Activation Inhibitor II(JSH-23)or Ras inhibitor,farnesylthiosalicylic acid(FTS). Further study shows that LPS-induced activation of Phospho-Rho A and Phospho-MEKl/2 were significantly inhibited by Rosiglitazone.The activation of NF-kB p65 in the nuclear extract of cells was also significantly suppressed by Rosiglitazone, moreover,the expression of NF-κB p65 was partly activated by GW9662(PPARg antagonist).NF-kB DNA binding activity was also demolished by Rosiglitazone.In summary,our data showed that PPARg agonist,Rosiglitazone suppresses LPS-activated MMP-2 secretion via Ras-MEK1/2 signaling pathways and NF-kB activation.PPARg agonist and Ras-MEK1/2 pathway may be another potential therapeutic target for the disease induced by chronic inflammation.

EXPRESSION OF MATRIX METALLOPROTEINASE-2 AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN HUMAN GLIOMA AND THEIR RELATION TO THE INVASION OF THE TUMOR

Objective To study the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 (MMP-2) in different grade human glioma. To investigate their relation to the pathological grade and invasion of the tumor. Methods The expression of MMP-2 and VEGF were determined by immunohistochemical technique in 48 cases of human glioma and 10 specimens of normal brain tissue. Results The expression levels of MMP-2 and VEGF in human glioma were positively related to tumor grades (P<0.01), and their expressions in the glioma of grade Ⅲ and Ⅳ were significantly different from those in the glioma of grade Ⅰ-Ⅱand normal brain tissue (P<0.01). The expression of MMP-2 was positively correlated to that of VEGF (P<0.01). Conclusion MMP-2 and VEGF were highly expression in human glioma and were positively related to the tumor grades. The synergic interaction of MMP-2 and VEGF promoted the angiogenesis and invasion of human glioma.