BACKGROUND: Matrix metalloproteinases (MMPs) have been implicated in the remodelling of extracellular matrix (ECM), including basement membrane. ECM remodelling is associated with pathological processes, including hepatic fibrosis, tumor invasion and metastasis. Tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 were known to inhibit MMP-9 and MMP-2, respectively. In the present study, we examined the expression of TIMP-1 and TIMP-2 in surgical specimen pairs of hepatocellular carcinoma and nontumoral liver and the correlation between their expression and clinicopathological characteristics. METHODS: The localization of both transcripts and protein of TIMP-1 and TIMP-2 was studied by using in situ hybridization and immunohistochemistry. RESULTS: TIMP-1 and TIMP-2 mRNA transcripts were found in tumor cells, hepatocyte, sinusoidal cells, endothelial cells and stromal cells. Signal intensity of TIMP-1 was stronger than that of TIMP-2. The results of immunohistochemical stainings were concordant with those obtained by in situ hybridization. Expression of TIMP-1 and TIMP-2 was observed in tumorous tissue, in nontumorous tissue and in the portions of the tumors adjacent to the capsules. However, a clear difference in TIMP-1 and TIMP-2 mRNA expression was not observed among the three tissue types. The intensity of TIMP-2 expression was generally weaker than that of TIMP-1, and the intensity of TIMP-1 and TIMP-2 mRNA expression did not correlate with variable clinicopathological characteristics. CONCLUSION: TIMPs was expressed in tumor cells and many cell types of the nontumoral liver. Further investigations for TIMPs' unknown functional role are needed.
Adult ; Aged ; Carcinoma, Hepatocellular/pathology ; Carcinoma, Hepatocellular/metabolism* ; Female ; Human ; Immunohistochemistry ; Liver Neoplasms/pathology ; Liver Neoplasms/metabolism* ; Male ; Middle Age ; RNA, Messenger/analysis ; Tissue Inhibitor-of Metalloproteinase-2/physiology ; Tissue Inhibitor-of Metalloproteinase-2/genetics* ; Tissue Inhibitor-of Metalloproteinase-2/analysis ; Tissue-Inhibitor of Metalloproteinase-1/physiology ; Tissue-Inhibitor of Metalloproteinase-1/genetics* ; Tissue-Inhibitor of Metalloproteinase-1/analysis

BACKGROUNDExposure of adult mice to more than 95% O2 produces a lethal injury by 72 hours. Nuclear factor kappa B (NF-κB) is a transcriptional factor that plays a key role in the modulation of cytokine networks during hyperoxia-induced acute lung injury (ALI). Osteopontin (OPN) is a phosphorylated glycoprotein produced principally by macrophages. Studies have reported that exogenous OPN can maintain the integrity of the cerebral microvascular basement membrane and reduce brain damage through inhibiting NF-κB activities in the brain after subarachnoid hemorrhage. However, it is not clear whether OPN can reduce lung injury during ALI by inhibiting transcriptional signal pathways of NF-κB and consequent inhibition of inflammatory cytokines. Thus we examined the effects and mechanisms of recombinant OPN (r-OPN) on ALI.

METHODSNinety-six mice were randomly divided into phosphate buffered saline (PBS) and r-OPN groups. Mice were put in an oxygen chamber (>95% O2) and assessed for lung injury at 24, 48, and 72 hours. Expressions of NF-κB, matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9), and tissue inhibitors of MMP-2 and MMP-9 (TIMP-1, TIMP-2) mRNA in lungs were examined with RT-PCR. Expression and distribution of NF-κB protein in lungs were measured with immunohistochemistry.

RESULTSExposure to hyperoxia for 72 hours induced more severe lung injury in the PBS group compared with the r-OPN group. Expression of NF-κB mRNA in the PBS group exposed to hyperoxia for 48 and 72 hours was significantly higher than the r-OPN group (P < 0.05). With 72-hour exposure, expression of TIMP-1 mRNA in the r-OPN group was significantly higher than that of the PBS group (P < 0.05). Expression of TIMP-2 mRNA in the r-OPN group at 48 and 72 hours was significantly higher than those in the PBS group (P < 0.05). After 72-hour exposure, expression of NF-κB protein in airway epithelium in the PBS group was significantly higher than that in the r-OPN group (P < 0.05).

CONCLUSIONr-OPN can inhibit the release and activation of MMPs through inhibition of the expression of NF-κB and promotion of the expression of TIMPs, and alleviate hyperoxia-induced ALI.

Acute Lung Injury ; genetics ; metabolism ; Animals ; Hyperoxia ; metabolism ; physiopathology ; Matrix Metalloproteinase 2 ; genetics ; metabolism ; Matrix Metalloproteinase 9 ; genetics ; metabolism ; Mice ; NF-kappa B ; genetics ; metabolism ; Osteopontin ; genetics ; metabolism ; Tissue Inhibitor of Metalloproteinase-1 ; genetics ; metabolism ; Tissue Inhibitor of Metalloproteinase-2 ; genetics ; metabolism

The aim of the present study was to investigate the protective effect of propofol on the experimental myocardial infarction in rats. The myocardial infarction model was established by ligating the anterior descending branch of left coronary artery in rats. Model rats were treated with propofol. Cardiac function was evaluated by echocardiography. Cardiac hemodynamic changes were detected by multiconductor biorecorder. Pathological changes in the infarcted myocardia were detected by HE staining. The expression levels of cardiac hypertrophy marker genes and fibrosis marker proteins were analyzed by real-time quantitative PCR and Western blot. The results showed that, compared with the sham surgery group, the model group exhibited larger infarct size (> 40%), impaired heart function, and significantly increased left ventricular end-diastolic pressure (LVEDP). Propofol reduced cardiac function impairment and decreased LVEDP in the model group. Propofol significantly reduced lung weight/body weight ratio, heart weight/body weight ratio, left ventricular weight/body weight ratio and left atrial weight/body weight ratio in the model group. Furthermore, after myocardial infarction, the administration of propofol significantly improved the diastolic strain rate, down-regulated the mRNA expression levels of myocardial hypertrophy markers, atrial natriuretic peptide and β-myosin heavy chain, and reversed the up-regulation of matrix metalloproteinase 2 (MMP2), MMP9 and tissue inhibitor of metalloproteinase-2 (TIMP-2) induced by myocardial infarction. These results suggest propofol can reduce adverse ventricular remodeling, cardiac dysfunction, myocardial hypertrophy and fibrosis after myocardial infarction, and has protective effect against the experimental myocardial infarction induced by coronary artery ligation in rats.
Animals ; Cardiotonic Agents/pharmacology* ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; Myocardial Infarction/drug therapy* ; Myocardium ; Propofol/pharmacology* ; Rats ; Tissue Inhibitor of Metalloproteinase-2/genetics* ; Ventricular Remodeling

Tissue inhibitor of metalloproteinases-2 (TIMP-2) inhibits tumor migration and invasion. Obtaining TIMP-2 protein is conducive to a comprehensive and in-depth study of its function and mechanism in tumorigenesis and development. We collected human TIMP-2 protein through prokaryotic expression in vitro. We expressed, purified and characterized human TIMP-2 protein. First, the human TIMP-2 gene was cloned from the cDNA obtained by reverse transcription of total RNA of human lung cancer A549 cells, and constructed to pET28a vector. The recombinant plasmid pET28a-TIMP-2 was transformed into Escherichia coli BL21(DE3) after restriction endonuclease digestion and sequencing analysis. The expression of TIMP-2 protein was induced by isopropyl-β-D-thiogalactoside (IPTG), and the expression conditions were optimized. After purification by nickel affinity column, the fusion protein His-TIMP-2 was identified by Western blotting method and its biological activity was detected by gelatin zymography. The fusion protein His-TIMP-2 existed in the form of inclusion body in E. coli. In a certain range, the concentration of IPTG had no significant effect on the expression amount of His-TIMP-2. But in this expression system, induction temperature and time were the key parameters, and the expression amount of His-TIMP-2 in E. coli increased with the increase of induction temperature. The purified and refolded fusion protein could effectively inhibit the activity of matrix metalloproteinases expressed by human lung cancer A549 cells. The acquisition of active fusion protein lays a foundation for further study of the function and mechanism of human TIMP-2, and is of great significance for tumor therapy.
Cloning, Molecular ; Escherichia coli/genetics* ; Humans ; Recombinant Fusion Proteins/genetics* ; Recombinant Proteins ; Tissue Inhibitor of Metalloproteinase-2/genetics*

OBJECTIVESTo explore the dynamic changes and interactions between MMP-2 and TIMP-2 during experimental liver fibrosis.

METHODSWistar rats were randomly allocated into a normal group and a model group. To induce liver fibrosis, rats were injected intraperitoneally with dimethylnitrosamine (DMN) three consecutive times in the first week, then two consecutive times per week, totally for 6 weeks. In the normal control group, rats were injected with saline by the same method as the model group. Animals were sacrificed 1, 4, 10, 17, 28, 42, 56 days after starting DMN injections. Conventional histological examinations of the livers were performed with hematoxylin and eosin and Masson staining. The fibrosis was classified into 0 to 4 stages. Hydroxyproline content was determined after liver tissues were hydrolyzed in HCl at 160 degree C for 2 hrs and then measured with spectrometry at 560 nm wavelength. mRNA levels of MMP-2 and TIMP-2 were determined by semi-quantitive RT-PCR. Gelatinase activity of MMP-2 was examined by zymography using gelatin substrate.

RESULTSIn the model group the hepatic MMP-2 mRNA expression started to increase 10 days after DMN administration and remained at a much higher level than in the normal group throughout the study period, while TIMP-2 mRNA expression started to be lower than in the normal group 17 days after DMN administration and reached the lowest level on the 28th day. Then it rapidly rebounded and remained higher than that in the normal group from the 42nd day to the end of the study period. TIMP-2/MMP-2 began to be lower by several days than that of the normal group after DMN administration through the remaining study period. Zymography showed that the enzymatic activities of both latent MMP-2 and active MMP-2 were increased during the process of liver fibrosis.

CONCLUSIONIn liver fibrosis, MMP-2 expression increases, while TIMP-2 expression relatively decreases. The enzymatic activities of MMP-2 increase as the liver fibrosis develops.

Animals ; Female ; Liver Cirrhosis, Experimental ; enzymology ; metabolism ; Male ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-2 ; biosynthesis ; genetics ; metabolism

OBJECTIVETo determine the molecular mechanisms involved in atrial fibrosis which occurs in patients with atrial fibrillation (AF) and to investigate their effects on the initiation and maintenance of AF.

METHODSThe right atrial tissue samples were taken from 73 patients with rheumatic heart disease who underwent heart valve replacement surgery. 34 patients had no history of AF (sinus rhythm group), 9 patients had paroxysmal AF and 30 patients had persistent AF. The mRNA content of collagen type I, collagen type III, MMP-2, TIMP-1, TIMP-2, TIMP-3 and TIMP-4 was measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and normalized to beta-actin or GAPDH.

RESULTSCompared to sinus rhythm group, the mRNA of collagen type I and MMP-2 increased significantly in the persistent AF group (all, P < 0.01), followed by the paroxysmal AF group (all, P < 0.05). The mRNA of collagen type III was slightly higher in both AF groups than in the sinus rhythm group, but the differences were not statistically significant (P > 0.05). The mRNA of TIMP-1, TIMP-2 and TIMP-3 was down-regulated in the persistent AF group (all, P < 0.01, respectively), however, the trends of reduction did not reach statistical significance in the paroxysmal AF group (P > 0.05). The mRNA of TIMP-4 remained compatible in each group. The mRNA of collagen type I was significantly correlated with left atrial dimension (r = 0.336, P = 0.004) and AF duration (r = 0.339, P = 0.003). The mRNA of MMP-2 was significantly correlated with the mRNA of TIMP-2 (r = -0.326, P = 0.006), the mRNA of collagen type I (r = 0.322, P = 0.006), left atrial dimension (r = 0.300, P = 0.011) and AF duration (r = 0.300, P = 0.010).

CONCLUSIONThe increased level of collagen type I associated with selective downregulation of TIMP-2 and upregulation of MMP-2 gene expression in atrium could be one of the molecular mechanisms of atrial fibrosis during atrial fibrillation, which correlates with the initiation and maintenance of AF.

Adolescent ; Adult ; Atrial Fibrillation ; metabolism ; pathology ; Collagen Type I ; genetics ; Female ; Fibrosis ; Humans ; Male ; Matrix Metalloproteinase 2 ; genetics ; Middle Aged ; Myocardium ; pathology ; RNA, Messenger ; analysis ; Tissue Inhibitor of Metalloproteinase-2 ; genetics ; Tissue Inhibitor of Metalloproteinases ; genetics

The fundamental event of cancer invasion and metastasis is the complicated interaction of cancer cells with host cells, in which event, a number of proteases and their inhibitors are involved. Matrix metalloproteinases are the potent proteases in degrading the basement membrane and extra cellular matrix and are inhibited by specific endogeneous inhibitors, tissue inhibitors of metalloproteinases-1(TIMP-1) and TIMP-2. The expression of mRNA for TIMP-1 and -2 was investigated by Northern blot analysis in specimens taken from 27 patients with primary gastric adenocarcinoma; 25 samples from the primary site, six from the metastatic lymph nodes and two from the peritoneal fluids. The expression for TIMP-1 and -2 was compared in primary gastric cancer tissues, metastatic lymph nodes and normal gastric mucosae. TIMP-1 mRNA was overexpressed in 24 (96%) out of 25 primary cancer tissues compared with the paired normal mucosae, while TIMP-2 was in 10 (40%). In six specimens of metastatic lymph nodes, TIMP-1 and -2 were overexpressed in 6 (100%) and 4 (67%) specimens, respectively. Of two specimens prepared from the peritoneal fluids, all specimens overexpressed TIMP-1 compared with the those of primary cancer tissues, while one (50%) specimen overexpressed TIMP-2. Immunohistochemical staining was done to investigate the localization of TIMP-1 and -2, demonstrating that the immunoreactivity for TIMP-1 and -2 was clearly detected in the cytoplasm of the stromal cells. These results suggest that both TIMP-1 and -2 are overexpressed by stromal cells in most of primary and some metastatic gastric cancer tissues and that TIMP-1 and TIMP-2, produced by stromal cells, may play an important role in inhibiting the proteolytic activity of matrix metalloproteinases originated from cancer cells, in gastric cancer.
Adenocarcinoma/*enzymology ; Blotting, Northern ; Glycoproteins/*biosynthesis/genetics ; Human ; Proteins/*biosynthesis/genetics ; RNA, Messenger/biosynthesis ; Stomach Neoplasms/*enzymology ; Support, Non-U.S. Gov't ; Tissue Inhibitor of Metalloproteinases ; Tissue Inhibitor-of Metalloproteinase-2

The fundamental event of cancer invasion and metastasis is the complicated interaction of cancer cells with host cells, in which event, a number of proteases and their inhibitors are involved. Matrix metalloproteinases are the potent proteases in degrading the basement membrane and extra cellular matrix and are inhibited by specific endogeneous inhibitors, tissue inhibitors of metalloproteinases-1(TIMP-1) and TIMP-2. The expression of mRNA for TIMP-1 and -2 was investigated by Northern blot analysis in specimens taken from 27 patients with primary gastric adenocarcinoma; 25 samples from the primary site, six from the metastatic lymph nodes and two from the peritoneal fluids. The expression for TIMP-1 and -2 was compared in primary gastric cancer tissues, metastatic lymph nodes and normal gastric mucosae. TIMP-1 mRNA was overexpressed in 24 (96%) out of 25 primary cancer tissues compared with the paired normal mucosae, while TIMP-2 was in 10 (40%). In six specimens of metastatic lymph nodes, TIMP-1 and -2 were overexpressed in 6 (100%) and 4 (67%) specimens, respectively. Of two specimens prepared from the peritoneal fluids, all specimens overexpressed TIMP-1 compared with the those of primary cancer tissues, while one (50%) specimen overexpressed TIMP-2. Immunohistochemical staining was done to investigate the localization of TIMP-1 and -2, demonstrating that the immunoreactivity for TIMP-1 and -2 was clearly detected in the cytoplasm of the stromal cells. These results suggest that both TIMP-1 and -2 are overexpressed by stromal cells in most of primary and some metastatic gastric cancer tissues and that TIMP-1 and TIMP-2, produced by stromal cells, may play an important role in inhibiting the proteolytic activity of matrix metalloproteinases originated from cancer cells, in gastric cancer.
Adenocarcinoma/*enzymology ; Blotting, Northern ; Glycoproteins/*biosynthesis/genetics ; Human ; Proteins/*biosynthesis/genetics ; RNA, Messenger/biosynthesis ; Stomach Neoplasms/*enzymology ; Support, Non-U.S. Gov't ; Tissue Inhibitor of Metalloproteinases ; Tissue Inhibitor-of Metalloproteinase-2

OBJECTIVETo construct the siRNA eukaryotic expression vectors targeting on TGFβ1, TIMP-1 and TIMP-2 and to investigate the inhibitory efficiency of target genes expression on rat hepatic stellate cell in vitro.

METHODSThe siRNA cDNA sequences of TGFβ1, TIMP-1 and TIMP-2 were designed, synthesized and inserted into plasmid pGenesil-1 respectively to generate eukaryotic expression plasmids. The plasmids were transfected into HSC T6 cells in vitro and the inhibitory efficiency of target genes expression was observed with real-time PCR and Western blot.

RESULTSThe eukaryotic expression vectors were constructed successfully. The expressions of TGFβ1 mRNA, TIMP-1 mRNA and TIMP-2mRNA in siRNA-transfected groups were decreased by 63.4% ± 8.0%, 64.5% ± 9.0% and 55.0% ± 17.0% respectively and the expressions of TGFβ1 protein, TIMP-1 protein and TIMP-2 protein were decreased by 57.8% ± 3.0%, 55.1% ± 5.0%, 49.3% ± 1.0% respectively as compared to the control groups.

CONCLUSIONSThe siRNA eukaryotic expression vectors constructed targeting on TGFβ1, TIMP-1 and TIMP-2 could reduce the expressions of target genes and they might be able to used for the exploration of new anti-fibrosis drugs genetically.

Animals ; Cell Line ; Gene Expression ; Genetic Vectors ; Hepatic Stellate Cells ; metabolism ; Plasmids ; RNA, Messenger ; genetics ; RNA, Small Interfering ; genetics ; Rats ; Tissue Inhibitor of Metalloproteinase-1 ; genetics ; Tissue Inhibitor of Metalloproteinase-2 ; genetics ; Transfection ; Transforming Growth Factor beta1 ; genetics

Animals ; Female ; Liver ; enzymology ; Liver Cirrhosis, Experimental ; enzymology ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-2 ; biosynthesis ; genetics