BACKGROUNDPressure therapy improves hypertrophic scar healing, but the mechanisms for this process are not well understood. We sought to investigate the differential expression of matrix metalloproteinases (Mmps) and collagen in posttraumatic hypertrophic scar tissue with mechanical pressure and delineate the molecular mechanisms of pressure therapy for hypertrophic scars.

METHODSFibroblast lines of normal skin and scar tissue were established and a mechanical pressure system was devised to simulate pressure therapy. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting assays were used to compare differences in the mRNA and protein expression of Mmps and collagen in scar fibroblasts before and after pressure therapy.

RESULTSThe expression differed between the hypertrophic scar cell line and the normal cell line. RT-PCR assays showed that Collagen I, highly expressed in the hypertrophic scar cell line, decreased significantly after pressure therapy. Mmp2, Mmp9, and Mmp12 expression in the hypertrophic scar tissue increased significantly after pressure therapy (P < 0.05). Western blotting assays further revealed that Mmp9 and Mmp12 expression increased significantly in the hypertrophic scar tissue after pressure therapy (P < 0.05) but not Mmp2 expression (P > 0.05).

CONCLUSIONMechanical pressure induces degradation of Collagen I in hypertrophic scar tissue by affecting the expression of Mmp9 and Mmp12.

Cell Line ; Cicatrix, Hypertrophic ; enzymology ; metabolism ; Collagen Type I ; genetics ; metabolism ; Humans ; Matrix Metalloproteinase 12 ; genetics ; metabolism ; Matrix Metalloproteinase 2 ; genetics ; metabolism ; Matrix Metalloproteinase 9 ; 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

OBJECTIVES: To study the role of the low-density lipoprotein receptor-related protein 1 (LRP1)-proline-rich tyrosine kinase 2 phosphorylation (pPyk2)-matrix metalloproteinases 9 (MMP9) pathway in hyperoxia-induced lung injury in neonatal rats. METHODS: A total of 16 neonatal rats were randomly placed in chambers containing room air (air group) or 95% medical oxygen (hyperoxia group) immediately after birth, with 8 rats in each group. All of the rats were sacrificed on day 8 of life. Hematoxylin and eosin staining was used to observe the pathological changes of lung tissue. ELISA was used to measure the levels of soluble LRP1 (sLRP1) and MMP9 in serum and bronchoalveolar lavage fluid (BALF). Western blot was used to measure the protein expression levels of LRP1, MMP9, Pyk2, and pPyk2 in lung tissue. RT-PCR was used to measure the mRNA expression levels of LRP1 and MMP9 in lung tissue. RESULTS: The hyperoxia group had significantly higher levels of sLRP1 and MMP9 in serum and BALF than the air group ( CONCLUSIONS The activation of the LRP1-pPyk2-MMP9 pathway is enhanced in hyperoxia-induced lung injury in neonatal rats, which may be involved in the pathogenesis of bronchopulmonary dysplasia.
Animals ; Animals, Newborn ; Hyperoxia/complications* ; Lung ; Lung Injury/etiology* ; Matrix Metalloproteinase 9/genetics* ; Rats

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

OBJECTIVETo study the effects of Tongxinluo on the expressions of matrix metalloproteinase-3 (MMP-3), MMP-9 and peroxisome proliferators-activated receptor gamma (PPARgamma) in atherosclerotic rabbits and explore the mechanism of its anti-atherosclerotic effect.

METHODSTwenty-four rabbits were randomized equally into control group, atherosclerotic model group (fed with high-fat diet for 14 weeks) and Tongxinluo group. The expressions of MMP-3, 9 and PPARgamma in the 3 groups were observed by means of immunohistochemistry.

RESULTSThe expressions of MMP-3, 9 and PPARgamma in the model group and Tongxinluo group were significantly higher than those in the control group (P<0.01). After high-fat diet feeding for 14 weeks, Tongxinluo group showed significantly lower expressions of MMP-3 and 9 but higher expression of PPARgamma than the model group (P<0.01).

CONCLUSIONTongxinluo can inhibit the expression of MMP-3 and 9 and increase the expression of PPARgamma, which might be the mechanism of its anti-atherosclerotic effect.

Animals ; Atherosclerosis ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Male ; Matrix Metalloproteinase 3 ; genetics ; metabolism ; Matrix Metalloproteinase 9 ; genetics ; metabolism ; PPAR gamma ; genetics ; metabolism ; Rabbits ; Random Allocation

Objective To explore the effect of overwork (OW) on extracellular matrix of arterial vessel wall in rats. Methods Random number grouping method was employed to assign 18 Sprague-Dawley rats into three groups(n=6):the control group(no special treatment),group OW(forced swimming twice a day for 15 days),and sleep deficiency(SD)+OW group(in addition to forced swimming twice a day,the rats were put on the platforms in water to limit sleep for 15 days).On the 16th day,the abdominal aorta and common carotid artery were collected after blood sampling from heart under deep anesthesia.A part of the abdominal aorta sample was taken for Masson staining of collagen fiber,and Verhoeff-Van Gieson staining was carried out for the elastic fiber of common carotid artery.Image J was employed for the quantitative analysis of collagen fiber and elastic fiber content.The expression of collagen 1(Col-1) protein was quantified by immunohistochemistry and the ultrastructure of vascular matrix was examined by transmission electron microscopy.The other part of the abdominal aorta sample was used to determine the mRNA levels of matrix metalloproteinase(MMP)-1,MMP-2,MMP-9,tissue inhibitor of metalloproteinases-1(TIMP-1),and Col-1 by quantitative real-time polymerase chain reaction. Results Compared with that in control group,the content of collagen fiber in groups OW and SD+OW had no significant change(all P>0.05);the content of elastic fiber in groups OW and SD+OW decreased(all P<0.001) and had no significant difference between each other(P>0.05).The vascular vessel wall of group OW showed slight fiber breakage,while that of group SD+OW presented wormhole-like or spongy fiber fragmentation.The mRNA levels of MMP-1 and MMP-2 in groups OW and SD+OW had no significant difference between each other(P>0.05) but were higher than that in control group(all P<0.001).The mRNA levels of MMP-9 and TIMP-1 had no significant difference among the three groups(all P>0.05).Groups OW and SD+OW had lower mRNA level(all P<0.001) and protein level(all P<0.001) of Col-1 than control group,while the mRNA and protein levels of Col-1 had no significant difference between groups OW and SD+OW(P>0.05). Conclusion OW can reduce the content of Col-1 and elastic fibers in the extracellular matrix of arterial vessels,destroy the elastic lamina of vascular wall,up-regulate the expression of MMP-1 and MMP-2,thereby injuring arterial vessels.
Animals ; Collagen Type I ; Extracellular Matrix/metabolism* ; Matrix Metalloproteinase 1/metabolism* ; Matrix Metalloproteinase 2/metabolism* ; Matrix Metalloproteinase 9/metabolism* ; RNA, Messenger/genetics* ; Rats ; Rats, Sprague-Dawley ; Tissue Inhibitor of Metalloproteinase-1/metabolism*

OBJECTIVETo study the association between the functional polymorphism of matrix metalloproteinases (MMPs) and the development of chronic obstructive pulmonary disease (COPD).

METHODS147 COPD patients and 120 healthy smoking controls were selected. Spirometry and chest X-rays had been taken. Questionnaires including sex, age, smoking history, occupational exposure were completed. MMP-9 (-1562 C/T), MMP-1(-1607 1G/2G), MMP-12 (-82 A/G), MMP-12(-357 Asn/ Ser) alleles were determined using PCR-RFLP method. Independent samples T test analysis was carried out to compare patients' age, smoking index, FEV1 /FVC, FEV1 % pred with that of healthy controlled group. The frequencies of genotypes and alleles between groups were analyzed by chi-square tests and multilogistic regression.

RESULTSMMP12 Asn/Asn, CT/AsnAsn were risk factors for smoking-induced COPD. The ORs were 2.361 (95% CI: 1.369-4.017) and 2.433(95% CI: 1.159-5.342) respectively while CC/1G1G/ SerSer seemed to be a protective factor for smoking-induced COPD, with OR as 0.457 and 95% CI as 0.231-0.911.

CONCLUSIONAsn/Asn, CT/AsnAsn might be susceptible genotypes while CC/GG/SerSer might serve as protective genotype.

Aged ; Case-Control Studies ; China ; ethnology ; Ethnic Groups ; genetics ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Logistic Models ; Male ; Matrix Metalloproteinase 1 ; genetics ; Matrix Metalloproteinase 12 ; genetics ; Matrix Metalloproteinase 9 ; genetics ; Polymorphism, Genetic ; Pulmonary Disease, Chronic Obstructive ; genetics

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.
Humans ; Immunohistochemistry ; Male ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; Matrix Metalloproteinase 9 ; biosynthesis ; genetics ; Neoplasm Invasiveness ; Prostatic Hyperplasia ; metabolism ; pathology ; Prostatic Neoplasms ; metabolism ; pathology

ObjectiveTo explore the expression of pituitary tumor transforming gene 1 (PTTG1) during the transformation of prostate cancer from androgen-dependent (ADPC) to androgen-independent (AIPC).

METHODSWe established an AIPC cell model LNCaP-AI by culturing the androgen-dependent LNCaP cell line in the hormone-deprived medium for over 3 months. The cell model was verified and the PTTG1 expression in the LNCaP cells was detected by Western blot and RT-PCR during hormone deprivation.

RESULTSThe AIPC cell model LNCaP-AI was successfully established. The PTTG1 expression was gradually increased in the LNCaP cells with the prolonged time of hormone deprivation and the expressions of matrix metalloproteinases MMP-2 and -9 were elevated at the same time.

CONCLUSIONSThe expression of PTTG1 is increased gradually in AIPC, which may be a target of gene therapy for advanced prostate cancer.

Blotting, Western ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Humans ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Neoplasms, Hormone-Dependent ; Prostatic Neoplasms ; enzymology ; genetics ; Securin ; genetics

OBJECTIVETo study the role of the synthesis and degradation of collagen at the transcription level during liver fibrogenesis due to schistosomiasis japonica in rabbits.

METHODSNew Zealand rabbits challenged by cercariae of Schistosoma japonicum (S. japonicum) were served as animal models for liver fibrosis. Liver specimens were collected through operations at 4, 6, 8, 10, 12, 16, 20, 24 and 28 wks after challenge. Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels of liver tissue were detected by RT-PCR + Dot blot. The size of egg granulomas and the degree of liver fibrosis were measured by histopathological examinations.

RESULTSType I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased simultaneously in the early stage after challenge. Most of them reached their peak at 10 weeks, and compared with normal controls, type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased by 12.0-, 11.0-, 6.6-, 10.0- and 11.0-fold, respectively, coinciding with the change of egg granulomas, i.e., the change in the inflammatory process. Then both collagen and collagenase mRNA levels decreased. Type I, III and IV collagen mRNA levels declined to 2-fold to 3-fold as compared with normal controls (P < 0.05), while MMP-1 and MMP-9 mRNA levels declined close to normal levels (P > 0.05) at 28 wks. This study shows that the synthesis and degradation of collagen keep a dynamic balance at the early stage of schistosomiasis japonica challenge, while at the later stages the quantity of collagen synthesis was higher than that of collagen degradation.

CONCLUSIONSIt was confirmed at transcription level that when the quantity of collagen synthesis was higher than that of collagen degradation liver fibrogenesis may be resulted in.

Animals ; Collagen ; metabolism ; Liver Cirrhosis, Experimental ; metabolism ; Matrix Metalloproteinase 1 ; genetics ; Matrix Metalloproteinase 9 ; genetics ; RNA, Messenger ; analysis ; Rabbits ; Schistosomiasis japonica ; metabolism ; Transcription, Genetic