基质金属蛋白酶和细胞因子在强直性脊柱炎骨破坏中的作用

强直性脊柱炎(ankylosing spondylitis,AS)是以中轴关节慢性炎症为主的原因不明的全身性免疫性疾病。其特点为几乎全部累及骶髂关节,常发生椎间盘纤维环及其附近韧带钙化和骨性强直,也可累及外周关节并造成关节软骨及骨的破坏,晚期可发生脊柱及外周关节强直、畸形以致严重功能受损[1]。所以我们必须强调重视AS骨质破坏发生机制的研究,有利于寻找有效药物,减少致残。1骶髂关节炎组织学研究较系统的骶髂关节炎组织学研究表明,AS的5个阶段不同程度存在滑膜炎、骨髓黏液样变、浅表软骨破坏、肌腱端炎、关节内纤维赘、新骨形成和骨性强直等众多病理表现;其中滑膜炎和软骨下骨髓黏液样变较肌腱端炎更能合理解     

Expression of epithelial matrix molecules collagen and laminin and corresponding integrins in chronic wounds

Re-epithelialization of cutaneous wounds is a coordinated process of proliferation and migration of keratinocytes at the wound edge. The study objective was to identify the differences in epidermal morphology, keratinocyte proliferation and matrix molecules (laminin 1, laminin 5, type IV collagen) and their specific integrin (α3, α6) expression in biopsies of meshed split thickness grafted and chronic wounds. The mean mitotic index of keratinocytes (ratio of cell cycle associated antigen Ki-67 expressing keratinocytes to basal keratinocytes) was highest in chronic wounds (38.7%) compared to acute wounds (22.25%, range 5.7% to 54%). The mean thickness of the hyper-proliferative epithelium at the wound edge of chronic wounds was 0.69 mm compared to 0.15 mm at the wound margin of split thickness grafted wounds. Both chronic wounds and skin grafted wounds exhibited strong laminin 5 immunoreactivity at the basal side of the epithelium, which extended under the most forward keratinocytes. Laminin 1 and type IV collagen immunoreactivity did not extend to the wound margin in either skin grafted or chronic wounds. In both transplanted skin and chronic wounds, the integrin sub-units α3 and α6 exhibited a strong pericellular immunoreactivity on the leading keratinocytes of the wound margin. Our data demonstrates that the proliferation of keratinocytes and the expression of associated integrins are not impaired in chronic wounds. Presented at the 33rd Congress of the Association of German Plastic Surgeons, Germany, 18–21 September, 2002.     

Selective coating of cylindrical matrices with a central hole. I. An interpretation of the swelling process

Cylindrical matrices were prepared by compression either of polyvinyl alcohol 100000 or mixtures of the excipient and a drug (sodium salicylate or theophylline). To modify the cylindrical shape, a hole was bored in the centre of the flat surface through both sides of the matrices. Different swellable systems were obtained applying an impermeable coating to one, two or three surfaces of the perforated matrices. The swelling of the perforated matrices was modified according to the number and the position of the coated surfaces (selective coating) and the loaded drug. Pseudo-zero order kinetics were obtained when the interior hole was the only uncoated surface.     

Matrix Metalloproteinase-2 and Tissue Inhibitor of Metalloproteinase-1 in the Retinal Pigment Epithelium and Interphotoreceptor Matrix: Vectorial Secretion and Regulation

Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE.     

Expression of matrix metalloproteinase matrilysin (mmp-7) was induced by activated ki-ras via ap-1 activation in sw1417 colon cancer cells

The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.     

尿激酶溶栓对大鼠局灶性脑缺血基质金属蛋白酶-9表达的影响

目的研究大鼠局灶性脑缺血后应用尿激酶(urokinase,UK)溶栓对基质金属蛋白酶-9(Matrix metalloproteinase-9,MMP-9)表达的影响,探讨MMP-9在UK溶栓引起的再灌注损伤及出血性转化中的作用。方法将实验动物随机分成3组进行研究(1)UK溶栓组;(2)缺血对照组;(3)假手术组。分别用免疫组织化学方法分析3组缺血后24hMMP-9的表达,对比研究两组MMP-9表达的差异性。结果缺血后24h前两组均有MMP-9的表达,但是UK溶栓组表达的程度明显高于缺血对照组;假手术组无MMP-9的表达。结论(1)缺血能导致MMP- 9的表达。(2)UK溶栓引起MMP-9表达的上调。     

基质金属蛋白酶与肺癌转移的关系

基质金属蛋白酶(matrix metalloproteinases，MMPs)是一组锌离子依赖的蛋白水解酶，在ECM降解中起着重要作用。目前研究表明，MMPs活性异常不仅能促进肿瘤血管形成，还是人类多种肿瘤侵袭和转移的必要条件。本文就与肺癌侵袭和转移有关的MMPs研究作一综述。     

Effect of different phospholipid-cholesterol membrane compositions on liposome-mediated formation of calcium phosphates

Summary The present report compares the effects of different membrane phospholipid (PL)-cholesterol compositions on the kinetics of liposome-mediated formation of calcium phosphates from metastable solutions (2.25 mM CaCl₂; 1.5 mM KH₂PO₄) at 22°C, pH 7.4 and 240 mOsm. In most experiments, the liposomes were composed of 7:2:X mixtures of phosphatidylcholine (PC), neutral or acidic phospholipids, and cholesterol (Chol, X=0, 10, 35, or 50 mol%). The neutral phospholipids (NPL) examined, in addition to PC, were phosphatidylethanolamine (PE) and sphingomyelin (Sph), and the acidic phospholipids (APL) examined were dicetylphosphate (DCP), dioleolylphosphatidylglycerol (DOPG), dioleolylphosphatidic acid (DOPA), phosphatidylserine (PS) and phosphatidylinositol (PI). The 7:2:X liposomes did not initiate mineralization in metastable external solutions per se or, with the exception of DOPA, show extensive Ca-PL binding. However, solution Ca²⁺ losses due to precipitation occurred when the liposomes were encapsulated with 50 mM KH₂PO₄ and made permeable to external Ca²⁺ with X-537A. The extent of these Ca²⁺ losses was sensitive to both the phospholipid and Chol makeup of the membrane. Moderate-to-extensive intraliposomal precipitation occurred in all 7PC:2APL and 7PC:2NPL liposomes containing 0 or 10 mol% Chol. In contrast, at 50 mol% Chol, mineralization inside all liposomes was negligible. The only significant discriminating effect on internal mineralization among the different phospholipids was observed at 35 mol% Chol, where mineral accumulations ranged from negligible to moderate. At 0 or 10 mol% Chol, extraliposomal precipitation was extensive in all but DOPA- and PS-containing liposomes. However, onece intraliposomal yields declined at the higher Chol levels, external mineralization was either delayed or totally blocked in all liposome preparations. Other experiments showed that Sph substituted for PC in 7NPL:2DCP:1Chol liposomes totally blocked both intra- and extraliposomal precipitaiton. PE substituted in this manner, however, blocked only extraliposomal precipitation. The results of this study suggest that interference of the membrane transport processes controlling intraliposomal precipitation [15] by high (50 mol%) Chol levels is not significantly compromised by the specific APL or NPL incorporated in the membrane. Similarly, the data suggest that Chol does not directly affect the specfic interactions of the different membrane APLs with the mineral phase. On the other hand, the substitution of other NPLs for PC can affect the role of APLs such as DCP in liposome-mediated mineralization.     

The Domain of Hypertrophic Chondrocytes in Growth Plates Growing at Different Rates

In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed) and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and 35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R ²= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of bone length growth. Received: 2 December 1996 / Accepted: 24 March 1997     

还原型谷胱甘肽对大鼠肝星状细胞TIMP—1表达的影响

目的 研究还原型谷胱甘肽对大鼠肝星状细胞（hepatic stellate,cells,HSC)中金属蛋白酶1组织抑制因子（TIMP－2）表达的影响。从分子和蛋白水平探讨还原型谷胱甘肽对大鼠肝纤维化的作用和可能机制。方法 采用50％CCl4制备大鼠肝纤维化模型，在造模过程中给予还原型谷胱甘肽进行干预。应用RT－PCR才Western Blot技术，在分子和蛋白水平检测体外分离大鼠HSC中的TIMP－1的表达情况。结果 还原型谷胱甘肽干预组与模型组和正常对照组相比，HSC中TIMP的表达降低（P＜0．05）。结论 还原型谷胱甘肽的干预可下调大鼠HSC中TIMP－1的表达，对实验性肝纤维化起到减轻作用。