Tissue inhibitor of metalloproteinase-3 expression affects clinicopathological features and prognosis of aflatoxin B1-related hepatocellular carcinoma

BACKGROUND The dysregulation of tissue inhibitor of metalloproteinase-3(TIMP3)was positively correlated with the progression of hepatocellular carcinoma(HCC).However,it is not clear whether TIMP3 expression is associated with the clinico-pathological features and prognosis of aflatoxin B1(AFB1)-related HCC(AHCC).A retrospective study,including 182 patients with AHCC,was conducted to explore the link between TIMP3 expression in cancerous tissues and the clinico-pathological characteristics and prognosis of AHCC.TIMP3 expression was detected by immunohistochemistry and its effects on the clinicopathological features and prognosis of AHCC were evaluated by Kaplan-Meier survival analysis and Cox regression survival analysis.Odds ratio,hazard ratio(HR),median overall survival time(MST),median tumor recurrence-free survival time(MRT),and corresponding 95%confidential interval(CI)was calculated to RESULTS Kaplan-Meier survival analysis showed that compared with high TIMP3 expression,low TIMP3 expression in tumor tissues significantly decreased the MST(36.00 mo vs 18.00 mo)and MRT(32.00 mo vs 16 mo)of patients with AHCC.Multivariate Cox regression survival analysis further proved that decreased expression of TIMP3 increased the risk of death(HR=2.85,95%CI:2.04-4.00)and tumor recurrence(HR=2.26,95%CI:1.57-3.26).Furthermore,decreased expression of TIMP3 protein in tissues with AHCC was significantly correlated with tumor clinicopatho-logical features,such as tumor size,tumor grade and stage,tumor microvessel density,and tumor blood invasion.Additionally,TIMP3 protein expression was also negatively associated with amount of AFB1-DNA adducts in tumor tissues.CONCLUSION These findings indicate that the dysregulation of TIMP3 expression is related to AHCC biological behaviors and affects tumor outcome,suggesting that TIMP3 may act as a prognostic biomarker for AHCC.

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.

Expression of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 in ulcerative colitis

AIM: To examine the expression of metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the colonic mucosa of patients with ulcer- ative colitis (UC). METHODS: Reverse transcription-polymerase chain re- action (RT-PCR) and immunohistochemistry were used to study the expression of MMP-1 and TIMP-1 at both mRNA and protein levels in patients with UC and con- trols. The relationship between MMP-1 mRNA, TIMP-1 mRNA, MMP-1 mRNA/TIMP-1 mRNA ratio and the sever- ity of clinical symptoms of the patients with UC were also analyzed. RESULTS: The expression of MMP-1 mRNA and TIMP-1 mRNA in the ulcerated and inflamed colonic mucosa was signifi cantly higher than that in the non-inflamed colonic mucosa (P < 0.001), but there was no statistically signif i- cant difference in the non-inflamed colonic mucosa of UC patients and normal controls (P > 0.05). The mRNA ex- pression of MMP-1 and TIMP-1 in ulcerated colonic mu- cosa of UC patients was increased by 80-fold and 2.2-fold, respectively when compared with the normal controls. In the inflamed colonic mucosa, the increase was 30-fold and 1.6-fold, respectively. Immunohistochemical analy- sis showed that among the ulcerated, inflamed, and non-inflamed colonic mucosae of UC patients and the normal controls, the positive rate of MMP-1 expression was 87%, 87%, 40% and 35% respectively, and the positive rate of TIMP-1 expression was 89%, 89%, 80% and 75%, respectively. Furthermore, the expression of MMP-1 mRNA, TIMP-1 mRNA and the MMP-1 mRNA/ TIMP-1 mRNA ratio were correlated with the severity of clinical symptoms (P <0.05).CONCLUSION: Excessive expression of MMP-1 in the diseased colonic mucosa causes excessive hydrolysis of the extracellular matrix (ECM) and ulceration in UC pa-tients. MMP-1 mRNA, TIMP-1 mRNA and MMP-1 mRNA/ TIMP-1 mRNA ratio can be used as biomarkers to judge the severity of clinical symptoms in patients with UC. Exogenous TIMP-1 or MMP-1 inhibitor therapy is a novel treatment for patients with UC.

Levels of matrix metalloproteinase-1 and tissue inhibitors of metalloproteinase-1 in gastric cancer

AIM:To evaluate the levels of preoperative serum matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in gastric cancer.METHODS:One hundred gastric cancer patients who underwent gastrectomy were enrolled in this study.The serum concentrations of MMP-1 and TIMP-1 in these patients and in fifty healthy controls were determined using an enzyme-linked immunosorbent assay.RESULTS:Higher serum MMP-1 and TIMP-1 levels were observed in patients than in controls (P < 0.001).Serum MMP-1 and TIMP-1 levels were positively associated with morphological appearance,tumor size,depth of wall invasion,lymph node metastasis,liver metastasis,perineural invasion,and pathological stage.They were not significantly associated with age,gender,tumor location,or histological type.CONCLUSION:Increased MMP-1 and TIMP-1 were associated with gastric cancer.Although these markers are not good markers for diagnosis,these markers show in advanced gastric cancer.

LOW DOSE PIRFENIDONE SUPPRESSES TRANSFORMING GROWTH FACTOR BETA-1 AND TISSUE INHIBITOR OF METALLOPROTEINASE-1, AND PROTECTS RATS FROM LUNG FIBROSIS INDUCED BY BLEOMYCIN

Objective To investigate the optimal dosage of pirfenidone for the treatment of pulmonary fibrosis induced by bleomycin in Wistar rats, and the alteration of expressions of transforming growth factor beta-1 （ TGF-β1 ）, tissue inhibitor of metalloproteinase-1 （ TIMP-1 ）, and matrix metalloproteinase-13 （ MMP-13 ） in lung tissue. Methods Male Wistar rats were endotracheally instilled with bleomycin or normal saline. Pirfenidone （25-800 mg · kg^-l · d^-1 ）, dexamethasone （3 mg/kg）, or 1% carboxymethylcellulose sodium were given daily by feed 2 days before instillation of bleomycin. Groups T7 and T14 were fed pirfenidone 50 mg · kg^-1 · d^-1 at 7 days or 14 daYs after bleomycin instillation. Lungs were harvested at 28 days after bleomycin instillation. Patholological changes in luffg tissues were evaluated with HE staining. Lung collagen was stained by sirius red and measured by content of hydroxypro- line. Expression of proteins of TGF-β1 TIMP-1, and MMP-13 were detected by Western blotting. Results At doses of 25, 50, and 100 mg· kg^- 1 · d ^- 1, pirfenidone had significant anti-fibrotic effects for bleomy- cin-induced rat pulmonary fibrosis, and these effects were most significantly attenuated at the dosage of 50 mg · kg^-1 ·d^ -1（ HE： P 〈 0. 01, P 〈 0.01, and P = 0.064; sirius red： P 〈0.05, P 〈 0.01, and P 〈 0.05 ; hydroxyproline： P = 0.595, P 〈 0.01, and P = 0.976）. Pirfenidone at a dosage of 50 mg · kg^- l · d^-1 inhibited protein expression of TGF-131 and TIMP-1 in lung tissue in the early phase （0.79 and 0.75 times of control group）, but had no effect on ex- nr^eelnn nf MMP-13. Conclusion Low dose pirfenidone, especially at dosage of 50 mg · kg^-1 · d^-1, has significant anti-fibrotic effects on bleomycin-induced rat pulmonary fibrosis. Pirfenidone partially inhibits the enhancement of the expression of TGF-131 and TIMP-β1 in lung tissue.

Matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 expression in early focal cerebral infarction following urokinase thrombolysis in rats

Activity of matrix metalloproteinase-9 increases following cerebral ischemia/reperfusion, and is associated with cerebral microvascular permeability, blood-brain barrier destruction, inflammatory cell infiltration and brain edema. Matrix metalloproteinase-9 also likely participates in thrombolysis. A rat model of middle cerebral artery infarction was established by injecting autologous blood clots into the internal carotid artery. At 3 hours following model induction, urokinase was injected into the caudal vein. Decreased neurological severity score, reduced infarct volume, and increased expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 were observed in the cerebral cortex 24 hours after urokinase thrombolysis. These results suggest that urokinase can suppress damage in the acute-early stage of cerebral infarction.

Plasma matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 as biomarkers of ulcerative colitis activity

AIM:Overexpression of mucosal metalloproteinases(MMP) has been demonstrated recently in inflammatory bowel disease.Their activity can be counterbalanced by the tissue inhibitor of metalloproteinases(TIMP).The aim of this study was to evaluate the effect of ulcerative colitis(UC)on MMP- 1 and TIMP-1 plasma concentrations,as two possible biomarkers of the disease activity. METHODS:MMP-1 and TIMP-1 plasma concentrations were measured with an enzyme immunoassay in 16 patients with endoscopically confirmed active UC. RESULTS:Plasma concentrations of both MMP-1(13.7±0.2 ng/ml)and TIMP-1(799±140 ng/ml)were significantly elevated in UC patients in comparison to healthy controls (11.9±0.9 ng/ml and 220±7 ng/ml respectively).There was no correlation between TIMP-1 and MMP-1 concentrations (r=0.02).TIMP-1 levels revealed significant positive correlations with scored endoscopic degree of mucosal injury, disease activity index and clinical activity index values as well as C-reactive protein concentration.There was no correlation between MMP-1 and laboratory,clinical or endoscopic indices of the disease activity.CONCLUSION: These results confirm the role of both MMP- 1 and TIMP-1 in the pathogenesis of ulcerative colitis. However only TIMP-1 can be useful as a biomarker of the disease activity, demonstrating association with clinical and endoscopic pictures.

Expression of matrix metalloproteinase-1 and tumor necrosis factor-α in ulcerative colitis

AIM： To examine the expression of matrix metalloproteinase-1 （MMP-1） and tumor necrosis factor-α （TNF-~~） in the colon mucosa of patients with ulcerative colitis （UC）.METHODS： Reverse transcription-polymerase chain reaction （RT-PCR） and immunohistochemistry were used to examine the expression of MMP-1 and TNF-α at both mRNA and protein levels in the colon mucosa of patients with UC. Correlation between MMP-1 and TNF-α and their correlation with the severity of the disease were also analyzed statistically.RESULTS： The expression of MMP-1 and TNF-α in the ulcerated and inflamed colon mucosa of patients with UC was significantly higher than that in the non-inflamed mucosa of normal controls at both mRNA and protein levels. Furthermore, the expression of MMP-1 and TNF-α in the ulcerated area was significantly higher than that in the inflamed area of patients with UC （0.9797 ± 0.1433 vs 0.6746 ± 0.0373, 0.8669 ± 0.0746 vs 0.5227 ± 0.0435, P 〈 0.05）. There was no statistically significant difference in the non-inflamed area of normal controls. There was a significant correlation between MMP-1 and TNF-c~ expression （0.9797 ± 0.1433 vs 0.8669 ± 0.0746, P 〈 0.05）, the correlating factor was 0.877. MMP-1 and TNF-α showed a significant correlation with the severity of the disease （0.0915 ：e 0.0044 vs 0.0749 vs 0.0032, 0.0932 ± 0.0019 vs 0.0724 ± 0.0043, P 〈 0.05）, their correlating factors were 0.942 and 0.890, respectively.CONCLUSION： Excessively expressed MMP-1 directly damages the colon mucosa by degrading extracellular matrix （ECM） in patients with UC. While damaging colon mucosa, excessively expressed TNF-α stimulates MMPs secreting cells to produce more MMP-1 and aggravates the mucosa damage. MMP-1 promotes secretion of TNF-α in a positive feedback manner to cause further injury in the colon mucosa. MMP-1 and TNF-α correlate well with the severity of the disease, and therefore, can be used clinically as biological markers to judge the severity of UC.

Interleukin-1 beta up-regulates tissue inhibitor of matrix metalloproteinase-1 mRNA and phosphorylation of c-jun N-terminal kinase and p38 in hepatic stellate cells

AIM： To study the relationship between interleukin-lbeta （IL-1β） up-regulating tissue inhibitor of matrix metalloproteinase-1 （TIMMP-1） mRNA expression and phosphorylation of both c-jun N-terminal kinase （INK） and p38 in rat heffatic stellate cells （HSC）. METHODS： RT-PCR was performed to measure the expression of TIMMP-1 mRNA in rat HSC. Western blot was performed to measure IL-1β-induced JNK and p38 activities in rat HSC. RESULTS： TIMMP-1 mRNA expression （1.191± 0.079） was much higher after treatment with IL-1β （10 ng/mL） for 24 h than in control group （0.545±0.091） （P〈0.01）. IL-1β activated INK and p38 in a time-dependent manner. After stimulation with IL-1β for 0, 5, 15, 30, 60 and 120 min, the INK activity was 0.982±0.299, 1.501±0.720, 2.133±0.882, 3.360±0.452, 2.181±0.789, and 1.385 ± 0.368, respectively. There was a significant difference in JNK activity at 15 min （P〈 0.01）, 30 min （P〈 0.01） and 60 min （P〈0.01） in comparison to that at 0 min. The p38 activity was 1.061±0.310, 2.050±0.863, 2.380±0.573, 2.973±0.953, 2.421±0.793, and 1.755 ± 0.433 at the 6 time points （0, 5, 15, 30, 60 and 120 min） respectively. There was a significant difference in p38 activity at 5 min （P〈0.05）, 15 min （P〈0.01）, 30 min （P〈0.01） and 60 min （P〈0.01） compared to that at 0 min. TIMMP-1 mRNA expression trended to decrease in 3 groups pretreated with different concentrations of SP600125 （10 μmol/L, 1.022±0.113; 20 μmol/L, 0.869±0.070; 40 μmol/L, 0.666±0.123）. Their decreases were all significant （P〈0.05, P〈0.01, P〈0.01） in comparison to control group （without SP600125 treatment, 1.163±0.107）. In the other 3 groups pretreated with different concentrations of SB203580 （10 μmol/L, 1.507±0.099; 20 μmol/L, 1.698±0.107; 40 μmol/L, 1.857±0.054）, the expression of TIMMP-1 mRNA increased. Their levels were higher than those in the control group （without SB203580 treatment, 1.027 ± 0.061） with a significant statistical significance （P〈 0.01）. CONCLUSION： IL-1β has a direct action on hepatic fibrosis by up-regulating TIMMP-1 mRNA expression in ratessionin in rate HSC.JNK and p38 mitogen-activated protein kinases （MAPKs） are involved in IL-1β-induced TIMMP-1 gene expression, and play a distinct role in this process, indicating that p38 and .INK pathways cooperatively mediate TIMP-1 mRNA expression in rat HSC.

Macrophage-derived matrix metalloproteinase-1 enhances aortic aneurysm formation in transgenic rabbits

Increased expression of matrix metalloproteinase-1(MMP-1)has been observed in the lesions of atherosclerosis and aneurysms;however,it is not fully understood whether macrophage-derived MMP-1 affects these diseases.To investigate whether macrophage-derived MMP-1 participates in the development of vascular diseases,we generated transgenic(Tg)rabbits expressing human MMP-1 in the monocyte/macrophage lineage under the control of the human scavenger receptor enhancer/promoter.Tg rabbits exhibited no visible abnormalities throughout their bodies.Western blotting analysis revealed that the amount of MMP-1 proteins in the conditioned media secreted from peritoneal macrophages of Tg rabbits was up to 3-fold higher than that in non-Tg rabbits.For the first experiment,Tg and non-Tg rabbits were fed a cholesterol diet for 16 weeks,and aortic and coronary atherosclerosis were evaluated.The gross lesion area of aortic atherosclerosis in Tg rabbits was not significantly different from that in non-Tg rabbits,but Tg rabbits had marked destruction of the medial elastic lamina of the aortic lesions on microscopic examination.For the second experiment,we generated aortic aneurysms by incubating with elastase.Compared with non-Tg rabbits,Tg rabbits exhibited a significantly greater aortic dilation.Increased macrophage-derived MMP-1 led to increased medial destruction in both aortic atherosclerosis and aneurysms.These results demonstrate that MMP-1 plays a different role in the pathogenesis of atherosclerosis and aneurysms.

Expression of tissue inhibitor of metalloproteinase-1 in progression muscular dystrophy

Objective Tissue inhibitor of metalloproteinase-1 （TIMP-1） is a muhifunctional protein that has thc capacity to modify cellular activities and to modulate matrix turnover. This paper revealed the contributive role of TIMP-1 in progressive muscular dystrophy （PMD）. Methods We examined the expression and cellular localization of TIMP-1 protein using biopsied frozen muscle from patients with Duchenne muscular dystrophy （DMD）, Becker muscular dystrophy （BMD） , congenital muscular dystrophy （CMD） by immunohistochemistry, double immunofluorescence and Western blot analysis. Results The results of immunohistochemistry and double immunofluorescence showed that TIMP-1 was positive only in vascular endothelial cells of normal muscles. Immunohistochemistry and Western blot analysis showed that the staining intensity was distinctly increased in some dystrophic muscles of PMD for TIMP-1. Double immunofluorescence revealed that TIMP-1 strongly expressed in the regenerating muscle fibers, macrophages and macrophage infiltrating necrotic fibers. Some activated fibroblasts in endomysium and perimysium of DMD and CMD muscles were also positive for TIMP- 1. Conclusion The functional consequence of overexpression of TIMP-1 in the dystrophic muscles is unknown, but the elevated local expression of TIMP-1 in diseased muscles of PMD and their distinct distribution pattern provide evidence that TIMP-1 may participate in the pathogenesis of PMD.

Expressions of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in malignant peripheral nerve sheath tumor

BACKGROUND： Matrix metalloproteinase-9 （MMP-9） can degrade collagen IV （the main structural ingredient of basilar membrane）, and it also plays an important role in tumor vascularization, tumor cell progression, formation of metastatic focus, etc. Tissue inhibitor of metalloproteinase-1 （T1MP-1） can bind with MMP-9 to form 1 ： 1 compound and inhibit its activity, and can negatively regulate the tumor progression and metastasis. OBJECTIVE： To analyze the relationship of MMP-9 and T1MP-1 expressions with the pathological grade, metastasis and prognosis of malignant peripheral nerve sheath tumor （MPNST）. DESIGN： An observational comparative experiment. SETTING： Heze Medical College. PARTICIPANTS： Fifty-eight surgical pathological samples, which were clearly diagnosed to be MPNST, were collected from the pathological laboratory archives in the Department of Pathology, Heze Municipal Hospital from January 1988 to December 2003. The MPNST pathological types were common tumor in 53 cases, malignant triton tumor in 2 cases, epithelial MPNST in 2 cases and MPNST with gland differentiation in 1 case. The pathological grade was grade 1 in 11 cases, grade 2 in 24 cases and grade 3 in 23 cases. Besides, the resected tumor samples of 20 patients with benign peripheral nerve tumor （10 cases of nerve sheath tumor and 10 cases of neurofibromatosis） and the normal peripheral nerves （by-products of some surgeries） of 5 patients were also collected. The samples were used with the approval of the patients. Rat-anti-human MMP-9, TIMP-1 monoclonal antibody and S-P kit were purchased from Fuzhou Maixin Biotechnology, Co.,Ltd. METHODS： The documented paraffin blocks were again prepared to sections of 5 lJ m. The expressions of MMP-9 and TIMP-1 in the samples were detected with mmunohistochemical S-P method. The relationships of the MPNST severity, recurrence, metastasis and survival rate with the expressions of MMP-9 and TIMP-1 were analyzed. MAIN OUTCOME MEASURES： Relationships of MMP-9 and TIMP-1 expressions with the MPNST severity and prognosis. RESULTS： ①Expressions of MMP-9 and TIMP-1 in three tissues： MMP-9 and TIMP-1 stainings were mainly observed in cytoplasm. Among the 58 MPNST patients, the MMP-9 expression was significantly higher than those in normal peripheral nerve and benign tumor （P 〈 0.05）, while the TIMP-1 expression in MPNST was lower than those in normal peripheral nerve and benign tumor （P 〈 0.05）. ②Relationship of MMP-9 and TIMP-1 expressions with the severity and prognosis of MPNST： The expressions of both proteins were observed in the four subtypes. The positive expression of MMP-9 in the MPNST patients of grades 2 - 3 was significantly higher than that in the MPNST patients of grade 1 （P 〈 0.05）, while the expression of MMP-9 was significantly lower than that in the MPNST patients of grade 1 （P 〈 0.05）. The metastatic rate was positively correlated with MMP-9 expression （r =1.696, P 〈 0.05）, but negatively correlated with TIMP-1 expression （r = - 2.125, P 〈 0.05）. CONCLUSION： MMP-9 and TIMP-1 are associated with MPNST pathological grades and metastasis, and can be used as the indicators for judging the severity and orognosis of MPNST.

Imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 may contribute to hemorrhage in cerebellar arteriovenous malformations

In this study, we determined the expression levels of matrix metalloproteinase-2 and -9 and matrix metalloproteinase tissue inhibitor-1 and -2 in brain tissues and blood plasma of patients undergoing surgery for cerebellar arteriovenous malformations or primary epilepsy （control group）. Immunohistochemistry and enzyme-linked immunosorbent assay revealed that the expression of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with cerebellar arteriovenous malformations than in patients with primary epilepsy. The ratio of matrix metalloproteinase-9 to matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with hemorrhagic cerebellar arteriovenous malformations compared with those with non-hemorrhagic malformations. Matrix metalloproteinase-2 and matrix metalloproteinase tissue inhibitor-2 levels were not significantly changed. These findings indicate that an imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-I, resulting in a relative overabundance of matrix metalloproteinase-9, might be the underlying mechanism of hemorrhage of cerebellar arteriovenous malformations.

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.

哮喘豚鼠气道重构中基质金属蛋白酶-9及抑制物TIMP-1的表达

目的:探讨哮喘豚鼠模型中基质金属蛋白酶(MMPs)及其组织抑制因子(TIMP)在哮喘气道重构发病中的作用.方法:重复雾化吸人卵蛋白建立豚鼠哮喘气道重构模型.实验分为对照组、哮喘激发4,6和8wk组.免疫组化方法结合显微图像分析检测MMP9,TIMP1的表达.半定量PCR检测MMP9及TIMP1mRNA水平.结果:①哮喘各组动物均出现管壁增厚、平滑肌增生等气道重构的特征性改变.②哮喘豚鼠MMP9的mRNA表达:哮喘4wk组为(0.52±0.05),哮喘6wk组为(0.74±0.05);哮喘8wk组为(0.48±0.04);对照组为(0.21±0.04);哮喘各组与对照组组间比较差异有统计学意义(P<0.05).哮喘豚鼠TIMP1的mRNA水平:哮喘4wk组为(0.36±0.04);哮喘6wk组为(0.83±0.05);哮喘8wk组为(0.97±0.05);对照组为(0.20±0.02);哮喘各组与对照组组间比较差异有统计学意义(P<0.05).③免疫组化的结果和RTPCR的结果一致.④在哮喘各时段组中,MMP9的表达增高自第4wk时明显变缓,而TIMP1仍持续增高,导致MMP9/TIMP1比例下降.结论:哮喘的气道重构与MMP9和TIMP1的表达密切相关,而二者的比例可能反映气道重构的严重程度.

丁苯酞预处理对脑缺血再灌注损伤大鼠基质金属蛋白酶-9、基质金属蛋白酶组织抑制因子-1和血脑屏障的影响

目的：探讨丁苯酞预处理对脑缺血再灌注损伤大鼠基质金属蛋白酶-9（MMP-9）、基质金属蛋白酶组织抑制因子-1（TIMP-1）和血脑屏障的影响.方法：90只雄性SD大鼠随机分为假手术组,模型组,NBP预处理低剂量组、中剂量组、高剂量组.采用线栓法制作大脑中动脉栓塞（MCAO）模型,缺血2h再灌注24 h后以干湿重法测定脑组织含水量,伊文思蓝（EB）评估血脑屏障的破坏程度,实时PCR检测MMP-9及TIMP-1 mRNA的表达水平.结果：脑缺血再灌注后,脑组织含水量及EB含量明显增加,MMP-9和TIMP-1表达均增强,与假手术组比较差异有统计学意义.丁苯酞预处理各组脑组织含水量及EB含量较模型组明显下降,MMP-9表达显著减少,TIMP-1表达明显增加,丁苯酞预处理中、高剂量组差异无统计学意义.结论：丁苯酞预处理对脑缺血再灌注损伤大鼠可通过调节MMP-9/TIMP-1的表达,降低血脑屏障通透性,减轻脑水肿,发挥预防性保护作用.

Ets-1转录因子在大鼠糖尿病肾病中的作用

目的观察转录因子Ets-1、基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-2组织抑制剂(TIMP-2)、平滑肌肌动蛋白(α-SMA)及Ⅳ型胶原(ColⅣ)在实验性糖尿病肾病(DN)进程中的表达及意义。方法雄性SD大鼠随机分成对照组(NC组,n=30);糖尿病组(DM组,n=40),腹腔注射链脲佐菌素(STZ)诱导糖尿病动物模型。STZ注射后第1、4、8、12、16周分别处死各实验组动物6～8只,采用免疫组化观察各组大鼠肾内Ets-1、MMP-2、TIMP-2、α-SMA及ColⅣ表达,并进行免疫双染共定位分析。结果免疫组化表明,同NC组相比,DM组Ets-1在肾小球、肾小管间质的表达于STZ注射后第1周明显增加(P<0.05),至第4、8周分别达到高峰(P<0.05),随后呈下降趋势,16周降至最低(P>0.05)。MMP-2在肾小球内的表达与Ets-1在肾小球内的表达相似;DM组TIMP-2在肾小球及肾小管间质的表达于STZ注射后第1周开始增加,第16周升至最高(P<0.01);肾小球内MMP-2/TIMP-2比率于STZ注射后第1周显著性升高(P<0.01),第4周起明显下降(P<0.01),第12、16周时甚至低于相同时间点NC组大鼠,有显著性统计学差异(均P<0.01),而肾小管间质内MMP-2/TIMP-2比率于STZ注射后第4周开始明显降低(P<0.05),并且随病程进展进一步下降;DM组ColⅣ在肾小球及肾小管间质内的沉积于STZ注射后第1周开始增加,第16周达高峰(P<0.05)。α-SMA在肾小球内及肾小管间质的表达于STZ注射后第1周开始增加,并且随病程进展逐渐增加,第16周升至最高(P<0.05)。相关分析表明,DM组肾小球及肾小管间质内Ets-1表达与MMP-2的表达呈显著正相关(r=0.856,P<0.01;r=0.642,P<0.01),而与MMP-2/TIMP-2比率呈负相关(r=-0.549,P<0.01;r=-0.580,P<0.01);MMP-2/TIMP-2比率与ColⅣ的表达呈显著负相关(r=-0.701,P<0.01;r=-0.626,P<0.01)。免疫双染显示,Ets-1阳性的肾小球固有细胞及肾小管间质细胞同时出现MMP-2阳性表达,TIMP-2染色阳性的肾小球固有细胞及肾小管间质细胞同时具有α-SMA阳性表达。结论 Ets-1转录因子可能通过调节MMP-2/TIMP-2系统平衡而影响细胞外基质(ECM)沉积,对DN基质重塑起关键性作用。

Survivin、TGFβ3与TIMP-1慢病毒载体的构建及其人髄核细胞表达

目的构建人生存素（Survivin）、转化生长因子03（TGFtβ3）与基质金属蛋白酶抑制剂-1（TIMP-1）三基因过表达慢病毒载体，通过一次转染，实现Survivin、TGFβ3、TIMP-1三基因在人退变椎间盘髓核细胞的稳定转染，为逆转或延缓椎间盘退变的基因治疗提供实验基础。方法应用Survivin、TGFβ3、TIMP-1慢病毒载体联合转染人退变髓核细胞，应用Real—TimePCR技术检测转染后基因表达情况。结果人退变椎间盘髓核细胞在转染后1周，Survivin、TGFβ3、TIMP-1三基因在基因水平均获得稳定过表达，并且其表达能维持细胞传至第3代或更久。Real—TimePCR检测结果显示，目的病毒组Survivin、TGFβ3、TIMP-1均过表达，其相对表达量与空白组比较，差异有显著性（F=12．96～3889．70，P〈O．05）。结论Survivin、TGFβ3与TIMP-1慢病毒载体能够稳定转染人退变椎间盘髓核细胞，并且能长时间维持其表达，从而发挥生物学效应。

携TIMP-1基因RNAi慢病毒载体感染大鼠HSC-T6细胞抑制目的基因表达

目的验证构建成功的携基质金属蛋白酶组织抑制因子-1(TIMP-1)基因特异性小干扰RNA的慢病毒载体对目的基因表达的抑制效应。方法以慢病毒质粒感染HSC-T6细胞,在感染6天和8天后,观察慢病毒感染效率;采用定量PCR法检测TIMP-1 mRNA水平变化;采用免疫印迹法检测TIMP-1蛋白表达变化。结果在慢病毒载体感染6天时,TIMP-1 mRNA水平较正常对照组下降约0.668倍[2-ΔΔCt为(0.668±0.046)],下降程度明显高于阴性对照组[2-ΔΔCt为(1.001±0.041),(P<0.05)];在慢病毒感染6天和8天时,RNAi组对TIMP-1蛋白表达具有明显的抑制作用,且以感染第6天为显著。结论构建成功的携TIMP-1基因特异性RNAi慢病毒载体能有效感染HSC-T6细胞,并抑制目的基因的表达。

Methodologic research on TIMP-1,TIMP-2 detection as a new diagnostic index for hepatic fibrosis and its significance

AIM: To set up a new method to detect tissue inhibitors of metalloproteinase-1 and -2(TIMP-1 and TIMP-2) in sera of patients with hepatic cirrhosis, and to investigate the expression and location of TIMP-1 and TIMP-2 in liver tissue of patients with hepatic cirrhosis, and the correlation between TIMPs in liver and those in sera so as to discuss whether TIMPs can be used as a diagnosis index of hepatic fibrosis. METHODS: The monoclonal antibodies (McAbs) of TIMP-1 and TIMP-2 were used to sensitize erythrocytes, and solid-phase absorption to sensitized erythrocytes (SPASE) was used to detect TIMP-1 and TIMP-2 in the sera of patients with hepatic cirrhosis. Meanwhile, with the method of in situ hybridization and immunohistochemistry, we studied the mRNA expression and antigen location of TIMP-1 and TIMP-2 in the livers of 40 hepatic cirrhosis patients with pathologic diagnosis. RESULTS: With SPASE, they were 16.4% higher in the acute hepatitis group, 33.3% higher in the chronic hepatitis group, and the positive rates were 73.6% and 61.2% respectively in sera of hepatic cirrhosis patients, which were remarkably higher than those in chronic hepatitis and acute hepatitis group (P【0.001). In 40 samples of hepatic cirrhosis tissues, all of them showed positive expression of TIMP-1 and TIMP-2 mRNA detected with immunohistochemistry or in situ hybridization (positive rate was 100%). Expression of TIMPs in different degrees could be found in liver tissue with cirrhosis. TIMPs were located in cytoplasm of liver cells of patients with hepatic cirrhosis. There was a significant correlation between serum TIMPs level and liver TIMPs level. CONCLUSION: SPASE is a useful method to detect the TIMP-1 and TIMP-2 in sera of patients with hepatic cirrhosis, and TIMP-1 and TIMP-2 can be considered as a useful diagnostic index of hepatic fibrosis, especially TIMP-1.