Inhibition of breast cancer cell extracellular matrix degradative activity by chemically modified tetracyclines

BACKGROUND: Inhibition of tumour cell proliferation, invasion and metastasis by chemically modified tetracyclines has been ascribed to inhibition of matrix metalloproteinase (MMP) activity. METHODS: Exposure of the human breast carcinoma cell line MDA-MB-231 or its MMP-9-overproducing transfected clone (E-10) to 6-demethyl, 6-deoxy, 4-de [dimethylamino]-tetracycline (CMT-3), a chemically modified non-antimicrobial tetracycline followed by analysis using gelatinase activity assay, zymography, degradation of radiolabelled extracellular matrix (ECM), Western blotting, TNF-alpha ELISA and cell viability assays. RESULTS: CMT-3 treatment results in diminution in extracellular MMP-9 protein levels as well as inhibition of gelatinase activity. This prevents cell-mediated ECM degradation without inducing general cytostasis or cytotoxicity. Culturing E-10 cells in 10 or 20 microM CMT-3 diminished secreted MMP-9 levels by 45% or 60%, respectively, but did not affect levels of most other secreted proteins, including tissue inhibitor of Metalloproteinases (TIMP-1). ECM degradation by E-10 cells or their conditioned medium was inhibited by approximately 20%-30% in the presence of 20 microM CMT-3, reflecting inhibition of MMP-9 activity in addition to diminution of released MMP-9 levels. TNF-alpha levels were also diminished in E-10 conditioned medium in the presence of CMT-3, but cell viability, measured by MTS reduction and cytosolic LDH retention, was unaffected. CONCLUSIONS: It is proposed that the reduction in ECM-degradative activity reflects diminished levels of expression as well as inhibition of enzymatic activity of MMPs released by cells in the presence of CMT-3. These multiple effects of CMT-3 may offer promise for use in suppressing tumour invasion, and if used in conjunction with other chemotherapy agents, may lead to more successful treatment of cancer.     

Inhibition of breast cancer cell extracellular matrix degradative activity by chemically modified tetracyclines

BACKGROUND. Inhibition of tumour cell proliferation, invasion and metastasis by chemically modified tetracyclines has been ascribed to inhibition of matrix metalloproteinase (MMP) activity.

METHODS. Exposure of the human breast carcinoma cell line MDA‐MB‐231 or its MMP‐9‐overproducing transfected clone (E‐10) to 6‐demethyl, 6‐deoxy, 4‐de [dimethylamino]‐tetracycline (CMT‐3), a chemically modified non‐antimicrobial tetracycline followed by analysis using gelatinase activity assay, zymography, degradation of radiolabelled extracellular matrix (ECM), Western blotting, TNF‐α ELISA and cell viability assays.

RESULTS. CMT‐3 treatment results in diminution in extracellular MMP‐9 protein levels as well as inhibition of gelatinase activity. This prevents cell‐mediated ECM degradation without inducing general cytostasis or cytotoxicity. Culturing E‐10 cells in 10 or 20?µM CMT‐3 diminished secreted MMP‐9 levels by 45% or 60%, respectively, but did not affect levels of most other secreted proteins, including tissue inhibitor of Metalloproteinases (TIMP‐1). ECM degradation by E‐10 cells or their conditioned medium was inhibited by ～ 20%–30% in the presence of 20?µM CMT‐3, reflecting inhibition of MMP‐9 activity in addition to diminution of released MMP‐9 levels. TNF‐α levels were also diminished in E‐10 conditioned medium in the presence of CMT‐3, but cell viability, measured by MTS reduction and cytosolic LDH retention, was unaffected.

CONCLUSIONS. It is proposed that the reduction in ECM‐degradative activity reflects diminished levels of expression as well as inhibition of enzymatic activity of MMPs released by cells in the presence of CMT‐3. These multiple effects of CMT‐3 may offer promise for use in suppressing tumour invasion, and if used in conjunction with other chemotherapy agents, may lead to more successful treatment of cancer.     

Dynamic changes of matrix metalloproteinases and their tissue inhibitors in severe sepsis

Purpose

Little is known about the dynamic changes of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) in sepsis. Our aim was therefore to investigate the time course of MMPs and their inhibitors in patients experiencing severe sepsis.

Methods

Our prospective controlled analysis included 38 patients with severe sepsis. Plasma levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured daily at a 5-day-long period with enzyme-linked immunosorbent assay. Seventeen healthy volunteers were invited as controls.

Results

MMP-2 showed no difference compared to controls, whereas significantly elevated MMP-9 levels were detected on admission (P < .005). Significantly elevated but declining TIMP-1 levels were measured during the whole trial (P < .002-.004). Except for the second day, TIMP-2 levels were significantly lower than controls (P < .05-.009). MMP2/TIMP-1 ratios were significantly lower in septic patients (P < .03-.006), whereas MMP-2/TIMP-2 ratios were elevated throughout our study (P < .03-.006). MMP-9/TIMP-1 ratios were significantly lower at the first 3 days (P < .05-.008). MMP-9/TIMP-2 was significantly elevated on admission (P < .006).

Conclusions

Our research is the first follow-up study dealing with MMPs, TIMPs, and their ratios in severe sepsis. Our results indicate that MMPs and TIMPs may play a crucial role in severe sepsis, especially TIMP-1, MMP-9, and possibly TIMP-2, after an extensive study.     

Elevated plasma matrix metalloproteinases and their tissue inhibitors in patients with severe sepsis

Purpose

Matrix metalloproteinases (MMPs) are essential for tissue remodeling. Our objectives were to determine (1) the concentrations of MMPs and their tissue inhibitors (TIMPs) in plasma obtained from patients with severe sepsis, (2) to correlate changes in MMP and TIMP levels with disease severity, and (3) to investigate recombinant activated protein C (rAPC) actions on plasma MMP2, 9 activities from severe sepsis patients.

Materials and methods

Matrix metalloproteinase and TIMP levels were quantified in plasma from patients with severe sepsis using antibody microarrays and gelatin zymography.

Results

Plasma MMPs (3, 7, 8, 9) and TIMPs (1, 2, 4) on microarray were increased in severe sepsis on intensive care unit (ICU) day 1, with more than 3-fold increases in MMP3, MMP7, MMP8, MMP9, and TIMP4. Latent forms of MMP2, 9 on zymography were increased in plasma from patients with severe sepsis, whereas only half of severe sepsis patients showed active MMP9. Elevated MMP7 and MMP9 on ICU days 1 and 3 negatively correlated with multiple organ dysfunctions. The temporal activity patterns of MMP2, 9 during 21 ICU days were not altered in patients treated with rAPC or by the addition of exogenous rAPC to plasma.

Conclusion

Most plasma MMPs and TIMPS were elevated in patients with severe sepsis, but only a limited subset of MMPs (7, 9) negatively correlated with disease severity. Recombinant activated protein C does not appear to directly alter MMP2, 9 activities.     

Role of chemically modified tetracycline on TNF-alpha and mitogen-activated protein kinases in sepsis

Chemically modified tetracyclines are orally active inhibitors of multiple proteases and cytokines. In this study, we focused on the regulation of tumor necrosis factor (TNF)-alpha and mitogen-activated protein kinases (MAPKs) in sepsis and their reduction by treatment with nonantimicrobial chemically modified tetracycline-3 (CMT-3), which retains their antiinflammatory activity. Sepsis was induced in rats by cecal ligation and puncture (CLP). At 24 h and 1 h before CLP, treated rats received CMT-3 (25 mg/kg), and untreated rats received saline by gavage. At 0 h, 0.5 h, 1.5 h, and 24 h after CLP, blood and liver samples were collected. TNF-alpha was determined by ELISA, and MAPKs were determined by Western blot analysis. A significant activation of p38 MAPK was observed after 0.5 h and 1.5 h of sepsis that appeared to coincide with the increased circulating TNF-alpha level. The activation of p42/44 was increased after 24 h of sepsis, whereas that of SAPK/JNK was unaltered throughout the course of sepsis. CMT-3 pretreatment inhibited the TNF-alpha level as well as p38 MAPK activation seen after 0.5 and 1.5 h of CLP and also suppressed the activation of p42/44 after 24 h post-CLP. These results indicate increased activity of TNF-alpha and MAPK following sepsis and demonstrate the beneficial effect of CMT-3 in preventing the increase in TNF-alpha, p38 MAPK, p42/44 MAPK, and the progression of septic shock.     

Inhibition of matrix metalloproteinases by lung TIMP-1 gene transfer limits monocrotaline-induced pulmonary vascular remodeling in rats

Extracellular matrix dysregulation is key to the development of pulmonary hypertension (PH), suggesting a pivotal role for the proteases that control matrix remodeling. Both hypoxia- and monocrotaline-induced PH are associated with increased protease activity in the distal and proximal pulmonary arteries. However, the role of proteases is not completely understood. In hypoxic PH, matrix metalloproteinase (MMP) inhibition increased pulmonary vascular remodeling, whereas in monocrotaline PH, serine elastase inhibition reversed pulmonary vascular remodeling. These conflicting effects of protease inhibition may be ascribable to differences across experimental models in either the mechanisms underlying PH or the methods used to inhibit protease activity. In the present study, we investigated the effects of specific MMP inhibition on monocrotaline PH development. To inhibit lung MMP in rats exposed to monocrotaline (60 mg/kg as a single subcutaneous injection), we used intratracheal instillation of the adenovirus-mediated human TIMP-1 gene (Ad.hTIMP-1, 10(8) plaque-forming units) as in our previous study on hypoxic PH. MMP inhibition in lungs was evaluated by in situ zymography. Rats treated with Ad.hTIMP-1 had less severe pulmonary vascular remodeling evidenced by a decreased right ventricular hypertrophy, with decreased muscularization of peripheral pulmonary arteries and increased lung-cell apoptosis compared to controls. No periadventitial collagen accumulation was observed in distal pulmonary arteries, whereas elastin content was significantly increased in Ad.hTIMP-1-treated rats. These data support a deleterious role for proteases in toxic and inflammatory PH and indicate that MMPs may have opposite effects in different PH models.     

MMP-2、MMP-9、TIMP-1和TIMP-2在乳腺癌中的表达及临床意义

目的 研究MMP—2、MMP—9、TIMP—1和TIMP—2在乳腺癌中的表达及与临床病理特征的关系。方法 免疫组化SP法检测历例原发性乳腺癌、13例乳腺纤维腺瘤和15例乳腺纤维腺病中的蛋白表达。结果 ①乳腺癌中MMP—2、MMP—9的阳性表达显著高于乳腺纤维腺瘤和纤维腺病(P＜0．05)；②MMP—9的阳性表达与乳腺癌肿瘤大小、临床分期呈正相关(P＜0．05)，伴腋窝淋巴结转移的乳腺癌中MMP—9、MMP—2呈高表达，但TIMP—1显著低表达；乳腺癌中MMP—9与TIMP—1的表达呈负相关(P＜0.05)；③MMP—2、MMP—9表达的乳腺癌患者预后差。结论 乳腺癌中MMP—2、MMP—9表达显著高于乳腺良性病变；可作为判断乳腺癌预后的标记。     

Role of matrix metalloproteinases in intestinal inflammation

Matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitors of MMPs (TIMPs), are produced in the gastrointestinal tract by several structural cells. The balance between MMPs and TIMPs is essential for many physiological processes in the gut. However, imbalance between MMPs and TIMPs plays an important role in the pathophysiology of diverse intestinal inflammatory conditions. We reviewed the role of the MMP/TIMP system in the pathogenesis of intestinal inflammatory diseases and pharmacologic perspectives for the use of compounds that restore the MMP/TIMP balance.     

Relationship between matrix metalloproteinases/tissue inhibitors of matrix metalloproteinases systems and autoantibody patterns in systemic sclerosis

OBJECTIVE: Systemic sclerosis (SSc) is a connective tissue disease characterized by tissue fibrosis that reflects an imbalance between collagen production and degradation. Matrix metalloproteinases (MMPs) are a family of endopeptidases involved in the remodelling of extracellular matrix (ECM). This activity is controlled by tissue inhibitors of MMP (TIMPs). Aim of this study was the evaluation of MMP-9/TIMP-1 and MMP-2/TIMP-2 systems in patients with SSc. DESIGN AND METHODS: SearchLight Human MMP Array 1 was used to measure MMPs and TIMPs in 32 SSc patients and 32 matched healthy controls. RESULTS: SSc patients showed higher values of both MMP-9 and TIMP-1 in comparison with controls. The patients with anticentromere antibodies (ACA) positivity showed higher values of MMPs and TIMPs in comparison with either controls or the patients with anti-Scl70-positive antibodies. CONCLUSION: Results of this investigation suggest that SSc patients with ACA positivity, after a primary fibrogenetic noxa, react with a more abundant release of MMP/TIMP, whereas patients with anti-Scl70 antibody show a normal response.     

Targeting the tumor microenvironment with chemically modified tetracyclines: inhibition of laminin 5 gamma2 chain promigratory fragments and vasculogenic mimicry

The laminin 5 (Ln-5) gamma2 chain and matrix metalloproteinases (MMPs) MMP-2 and membrane type 1 (MT1)-MMP act cooperatively and are required for highly aggressive melanoma cells to engage in vasculogenic mimicry when cultured on a three-dimensional matrix. Furthermore, generation of Ln-5 gamma2 chain promigratory fragments by MMP-2 and MT1-MMP proteolysis is necessary for an aggressive tumor cell-preconditioned matrix to induce vasculogenic mimicry in poorly aggressive tumor cells. These observations suggest that treatment regimes that specifically target aggressive tumor cells may fail to take into account changes in the extracellular microenvironment that persist after removal or destruction of an aggressive tumor and could result in a recurrence or continuance of the tumor. As a potential therapeutic approach to address this concern, the work presented here measured the molecular consequences of adding a chemically modified tetracycline (CMT-3; COL-3) that inhibits MMP activity to aggressive metastatic melanoma cells in three-dimensional culture. COL-3 inhibited vasculogenic mimicry and the expression of vasculogenic mimicry-associated genes in aggressive cells, as well as the induction of vasculogenic mimicry in poorly aggressive cells seeded onto an aggressive cell-preconditioned matrix. Furthermore, molecular analysis revealed that COL-3 not only inhibited the generation of Ln-5 gamma2 chain promigratory fragments in the aggressive cell-preconditioned matrix but also inhibited the induction of Ln-5 gamma2 chain gene expression in poorly aggressive cells by the aggressive cell-preconditioned matrix. These results suggest that COL-3 (and related chemically modified tetracyclines) may be useful in targeting molecular cues in the microenvironment of aggressive tumors and could potentially be used in a combinatorial manner with other therapies that specifically target and kill aggressive tumor cells.     

Potent and selective inhibition of matrix metalloproteinases by lanthanide trichloride

Matrix metalloproteinases (MMPs) are a family of Zn-containing and Ca-dependent proteases with vital roles in extracellular matrix remodeling. Deregulation of MMPs occurs in many pathological conditions such as cardiovascular diseases, inflammation, and cancer. The therapeutic potential of MMP inhibitors has been demonstrated in diseases such as arthritis and cancer. Here we demonstrated that the 3-valent lanthanide compounds LaCl₃, TbCl₃, GdCl₃, YbCl₃, and EuCl₃ inhibit MMPs such as MMP-2, MMP-13, and MMP-14 (MT1-MMP). The inhibition is more potent and selective toward MT1-MMP compared to the other MMPs. EuCl₃ was further selected to study the enzyme kinetics of the MT1-MMP inhibition. The results showed that the inhibition is a mixed type with anti-competition and non-competitive types, which indicated that inhibition was achieved by the compound bound to the non-active center of MT1-MMP and changing the enzyme conformation. The interaction between EuCl₃ and MT1-MMP was further studied by UV-visible (UV-vis) light absorption. EuCl₃ caused a slight blue shift of the maximum absorption wavelength of MT1-MMP, indicating the interaction reduced protein hydrophobicity. Moreover, EuCl₃ exerted substantial inhibitory effects on the migration of HT-1080 cells. Thus, EuCl₃ may play a role in modulating tumor cell behavior by inhibiting MMPs activities especially the MT1-MMP activity. These findings provide initial insight into the biological activity and potential therapeutic value of EuCl₃.

The specific inhibition of EuCl₃ on MT1-MMP and it inhibits on HT-1080 cell migration in a dose-dependent manner.     

基质金属蛋白酶在大鼠肾小球硬化中的表达

目的检测基质金属蛋白酶-2（MMP-2）和基质金属蛋白酶-9（MMP-9）在大鼠局灶节段肾小球硬化中的表达,探讨其与细胞外基质沉积的关系。方法12只雄性Wistar大鼠,实验组7只,一次性静脉注射氨基核苷嘌呤霉素9mg/100g体重,对照组5只,静脉注射生理盐水一次,动态观察尿蛋白定量变化。第20周末宰杀,腹主动脉取血,检测血浆白蛋白、血脂、肾功能。留取肾脏,制备病理标本。应用免疫组织化学法观察两组大鼠肾组织中MMP-2、MMP-9和FN的表达,分析其在肾组织中的相对含量,及与蛋白尿程度的相关性。结果FSGS模型组大鼠用药后尿蛋白定量显著增高,血总胆固醇显著增高。肾脏病理变化示部分肾小球局灶节段硬化或全球性硬化,细胞外基质节段性增多。MMP-9在正常大鼠肾小球上皮细胞和内皮细胞有少量表达,在模型组大鼠肾组织中的表达显著减少（P〈0.05）;MMP-9的表达与尿蛋白定量之间无显著相关性。MMP-2在正常大鼠的肾小球动脉和肾小管间质有少量表达,在模型组大鼠肾组织中,MMP-2的表达略有减少（P〉0.05）;MMP-2的表达与尿蛋白的定量之间无显著相关性。在正常大鼠肾组织中FN表达于肾小球系膜区,基底膜及肾间质处,在模型组大鼠肾组织中FN的表达明显增多（P〈0.05）。FN的表达与尿蛋白定量、MMP-2的表达无显著相关性,与MMP-9的表达呈直线负相关。结论局灶节段肾小球硬化时,MMP-9的表达下调,可以引起FN降解减少,细胞外基质沉积,促进肾小球硬化的发生。     

Heparin affects matrix metalloproteinases and tissue inhibitors of metalloproteinases circulating in peripheral blood

Objectives

Blood sampling/handling alters matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) expression. The aim of this study is to evaluate the effects of high molecular weight heparin on MMP and TIMP expression in blood.

Design and methods

We analyzed by gelatin zymography and ELISA assays the effects of different heparin salts, dose- and time-dependence of MMP and TIMP concentrations in plasma and sera collected with and without clot-accelerator in plastic tubes from 50 healthy donors.

Results

The levels and zymography of MMP-2 did not show significant changes among all samples, and during time- and dose-dependent heparin treatments. MMP-9 and TIMP-2 expression were strongly affected by heparin, with significant increase of their content and gelatinolytic activity both in time- and in dose-dependent fashion. Addition of heparin allowed also the displacement of MMP-2 prodomain, favouring zymogen activation.

Conclusions

Heparin has direct and indirect effects, altering MMP/TIMP complexes circulating in blood, and increasing the release of TIMP-2. To avoid misinterpretations due to MMP/TIMP complex alteration and MMP prodomain displacement, heparin should be cautiously used in blood collection procedures.     

脓毒症大鼠肺基质金属蛋白酶-2/9表达与血必净干预

目的 观察创伤弧菌脓毒症大鼠肺基质金属蛋白酶(MMP)-2/9和组织型金属蛋白酶抑制剂(TIMP)-1/2的动态表达及血必净干预.方法 温州医学院生命科学院实验室,清洁级SD大鼠110只,随机(随机数字法)分为正常对照组(A组,n=10)、创伤弧菌脓毒症组(B组,n=50,采用大鼠左下肢皮下注射创伤弧菌悬液制作创伤弧菌脓毒症大鼠模型)及血必净干预组(C组,n=50,感染后0.5 h腹腔注射血必净4 mL/kg).B、C组大鼠于染菌后1,6,12,24,48 h麻醉后活杀,留取右肺标本.观察大鼠行为学变化,采用考马斯亮蓝法测肺通透性,采用逆转录-聚合酶链式反应(RT-PCR)法测肺MMP-2/9,TIMP-1/2 mRNA的表达,免疫组化法和双抗体夹心酶联免疫吸附法(ELISA)测肺MMP-2/9和TIMP-1/2的表达.数据采用单因素方差分析,并用LSD-t法进行组间两两比较,以P＜0.05为差异有统计学意义.结果 B组和C组肺通透性显著高于A组,C组显著低于B组.B组和C组MMP-2/9,TIMP-1/2mRNA显著升高,B组分别于6 h(0.344±0.108),6 h(1.230±0.377),12 h(0.523±0.098),12 h(0.280±0.070)达高峰(P＜0.05),C组分别于12 h(0.256±0.074),6 h(0.968±0.225),12 h(0.746±0.316),12 h(0.356±0.035)达高峰(P＜0.05),C组MMP-2/9mRNA升高趋势显著低于B组(P＜0.05),TIMP-1/2mRNA显著高于B组(P＜0.05).B组和C组MMP-2/9,TIMP-1/2蛋白也升高,B组分别于12 h(0.692±0.191),12 h(0.061±0.017),24 h(1384.42±91),24 h(41.04±3.60)达高峰(P＜0.05);C组分别于24 h(0.217±0.065),12 h(0.045±0.013),24 h(1617.22±103),24 h(47.66±3.58)达高峰(P＜0.05);C组MMP-2/9蛋白升高趋势低于B组(P＜0.05),TIMP-1/2蛋白早期与B组差别不大,后期显著高于B组(P＜0.05).结论 MMP/TIMP比例失衡是创伤弧菌脓毒症大鼠肺损伤机制之一,血必净可促进MMP/TIMP比例恢复平衡,对创伤弧菌脓毒症大鼠肺损伤具有保护作用.

Abstract：

Objective To detect the expression of MMP-2/9 and TIMP-1/2 in the lung of Vibrio vulnificus sepsis rats and observe the intervention of Xuebijing injection. Method One hundred and ten SD rats of clean grade were randomly(random number) divided into normal control group (group A, n = 10),Vibrio vulnificus sepsis group (group B, n = 50. Sepsis was reproduced in rats with subcutaneous injection in left lower limb with Vibrio vulnificus) and Xuebijin intervention group ( group C, n = 50. Rats were intraperitoneal(ip) with the dose of Xuebijing 4mL/kg at the time of 30 min later after infection). The rats in group B and C were sacrificed at 1 h, 6 h, 12 h, 24 h, 48 h after infection, the expression of MMP-2/9 and TIMP-1/2 were examined by PCR, Immunohistochemistry or ELISA methods, the lung permeability were measured by Coomassie Brilliant Blue method. Experimental data used single factor analysis of variance, and between groups by LSD method for pairwise comparison,P ＜0.05 statistically significant difference. Results The lung permeability increased both in group B and C compared with group A,and in group B were relatively higher. The lung MMP-2/9, TIMP-1/2mRNA expression in groups B and C compared with in group A was markedly higher, and reached the peak at 6 h(0. 344 ± 0. 108 ),6 h ( 1. 230 ± 0.377 ), 12 h (0.523 ±0.098),12 h(0.280±0.070) (P＜0.05) in group B while at 12 h(0.256 ±0.074),6 h(0.968±0.225) ,12 h(0.746 ±0. 316) ,12 h(0.356 ±0.035) (P ＜0. 05) in group C; the MMP-2/9mRNA expression in group C decreased(P＜0. 05) compared with the group B while the TIMP-1/2mRNA expression increased(P＜0. 05). The lung MMP-2/9, TIMP-1/2 protein expression in groups B and C compared with the group A(0.345±0.109) also increased, and the peak was at 12 h (0. 692 ± 0. 191 ), 12 h (0. 061 ±0.017) ,24 h(1384.42 ±91) ,24 h(41.04 ±3.60)in group B while at 24 h(0. 217 ±0.065) ,12 h(0. 045± 0. 013 ) ,24 h ( 1617.22 ± 103 ) ,24 h (47.66 ± 3.58 )in group C, the MMP-2/9 protein expression in group C was lower than in group B(P＜0.05), the TIMP-1/2 protein expression in group C was similar to in group B early while marked increased(P＜0.05)later. Conclusions MMP/TIMP imbalance was one of the mechanisms of the lung injury in the rats with Vibrio vulnificus sepsis, Xuebijing could restore the balance of MMP/TIMP ratio.     

脓毒症大鼠肺基质金属蛋白酶-2/9表达与血必净干预

Objective To detect the expression of MMP-2/9 and TIMP-1/2 in the lung of Vibrio vulnificus sepsis rats and observe the intervention of Xuebijing injection. Method One hundred and ten SD rats of clean grade were randomly(random number) divided into normal control group (group A, n = 10),Vibrio vulnificus sepsis group (group B, n = 50. Sepsis was reproduced in rats with subcutaneous injection in left lower limb with Vibrio vulnificus) and Xuebijin intervention group ( group C, n = 50. Rats were intraperitoneal(ip) with the dose of Xuebijing 4mL/kg at the time of 30 min later after infection). The rats in group B and C were sacrificed at 1 h, 6 h, 12 h, 24 h, 48 h after infection, the expression of MMP-2/9 and TIMP-1/2 were examined by PCR, Immunohistochemistry or ELISA methods, the lung permeability were measured by Coomassie Brilliant Blue method. Experimental data used single factor analysis of variance, and between groups by LSD method for pairwise comparison,P ＜0.05 statistically significant difference. Results The lung permeability increased both in group B and C compared with group A,and in group B were relatively higher. The lung MMP-2/9, TIMP-1/2mRNA expression in groups B and C compared with in group A was markedly higher, and reached the peak at 6 h(0. 344 ± 0. 108 ),6 h ( 1. 230 ± 0.377 ), 12 h (0.523 ±0.098),12 h(0.280±0.070) (P＜0.05) in group B while at 12 h(0.256 ±0.074),6 h(0.968±0.225) ,12 h(0.746 ±0. 316) ,12 h(0.356 ±0.035) (P ＜0. 05) in group C; the MMP-2/9mRNA expression in group C decreased(P＜0. 05) compared with the group B while the TIMP-1/2mRNA expression increased(P＜0. 05). The lung MMP-2/9, TIMP-1/2 protein expression in groups B and C compared with the group A(0.345±0.109) also increased, and the peak was at 12 h (0. 692 ± 0. 191 ), 12 h (0. 061 ±0.017) ,24 h(1384.42 ±91) ,24 h(41.04 ±3.60)in group B while at 24 h(0. 217 ±0.065) ,12 h(0. 045± 0. 013 ) ,24 h ( 1617.22 ± 103 ) ,24 h (47.66 ± 3.58 )in group C, the MMP-2/9 protein expression in group C was lower than in group B(P＜0.05), the TIMP-1/2 protein expression in group C was similar to in group B early while marked increased(P＜0.05)later. Conclusions MMP/TIMP imbalance was one of the mechanisms of the lung injury in the rats with Vibrio vulnificus sepsis, Xuebijing could restore the balance of MMP/TIMP ratio.     

Circulating matrix metalloproteinases and their inhibitors in hypertension

Growing experimental evidence indicates that matrix metalloproteinases (MMPs) are implicated in many cardiovascular diseases including hypertension and its chronic complications. It is now clear that MMPs have many more substrates other than components of the extracellular matrix. In fact, intracellular targets now include those associated with the cardiovascular system. Clinical studies have suggested that circulating MMPs may predict cardiovascular morbidity and mortality. It is highly probable that increased MMPs may predispose hypertensive patients to additional complications and clinical sequelae. In this article, we review the basic principles linking MMP activity with hypertension and summarize clinical studies examining two specific MMPs (MMP-2 and -9) in hypertension. We also discuss how antihypertensive drugs may affect MMPs and their endogenous inhibitors, i.e., tissue inhibitors of matrix metalloproteinases (TIMPs). Circulating MMPs may predict increased risk of developing cardiovascular complications associated with hypertension. As such, patients could benefit from early pharmacologic intervention including use of MMP inhibitors.     

胃癌进展时基质金属蛋白酶的作用

胃癌是消化道最普通的恶性肿瘤之一,其特征是临床表现晚和病程进展迅速.由于它具有侵袭性和早期转移的能力,可降解细胞外基质和基底膜屏障.基质金属蛋白酶在这个过程中起着决定性的作用.这些酶影响早期癌发生、肿瘤发展和生长以及在原始位置和转移位置癌细胞的侵袭.然而,需要进一步研究此酶及它们的抑制剂在肿瘤生物学中的作用,以改善胃癌病人的诊断和治疗.