Effect of Bisphenol A on invasion ability of human trophoblastic cell line BeWo

Bisphenol A (BPA) is a kind of environmental endocrine disruptors (EEDs) that interfere embryo implantation. Trophoblast invasion plays a crucial role during embryo implantation. In this study, the effects of BPA on invasion ability of human trophoblastic cell line BeWo and its possible mechanism were investigated. BeWo cells were exposed to BPA and co-cultured with human endometrial cells to mimic embryo implantation in transwell model. The proliferation and invasion capability of BeWo cells were detected. The expression of E-cadherin, DNMT1, MMP-2, MMP-9, TIMP-1 and TIMP-2 were also analyzed. The results showed that the invasion capability of BeWo was reduced after daily exposure to BPA. BPA had biphasic effect on E-cadherin expression level in BeWo cells and expression level of DNMT1 was decreased when treated with BPA. Moreover, BPA treatment also changed the balance of MMPs/TIMPs in BeWo cells by down-regulating MMP-2, MMP-9 and up-regulating TIMP-1, TIMP-2 with increasing BPA concentration. Taken together, these results showed that BPA treatment could reduce the invasion ability of BeWo cells and alter the expression level of E-cadherin, DNMT1, TIMP-1, TIMP-2, MMP-2, and MMP-9. Our study would help us to understand the possible mechanism of BPA effect on invasion ability of human trophoblastic cell line BeWo.     

Altered proteolytic activity and expression of MMPs and aggrecanases and their inhibitors in Kashin–Beck disease

Kashin–Beck disease (KBD) is a chronic, deforming endemic osteoarticular disease with altered metabolism of the cartilage matrix. Matrix metalloproteinases (MMPs), aggrecanases (ATAMTSs), and their inhibitors (TIMPs) play important roles in cartilage formation and matrix degradation. This study investigated these proteases and inhibitors in young KBD cartilage. The percentages of chondrocytes staining for MMP‐1/‐13 and MMP‐generated DIPEN neoepitope, aggrecanase‐generated ITEGE neoepitope in aggrecan in KBD patients were significantly higher than in controls. However, TIMP‐1 was significantly less numerous than in controls in the superficial and middle zones of KBD samples, the percentage of chondrocytes staining for the TIMP‐2 was significantly higher than in controls. Staining for MMP‐1/‐13 and, TIMP‐1/‐2 in KBD patients was prominent in the superficial zone and the middle zone of articular cartilage. Staining for ITEGE and DIPEN neoepitopes in KBD samples was prominent in the superficial zone and the middle zone of articular cartilage. The strongest staining for the MMP and aggrecanase‐generated neoepitopes was adjacent to areas of chondronecrosis. These results indicated that KBD cartilage destruction depends on collagen‐ and aggrecan‐degrading proteases such as collagenases (MMP‐1/‐13), as well as aggrecanases. Increased TIMP‐2 level adjacent to necrotic areas suggest that attempted repair mechanism are also activated. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:47–55, 2015.     

Staphylococcus aureus on the effect of expression of MMPs/TIMPs and uPA system in bovine mammary fibroblasts

BackgroundBovine mammary fibrosis is characteristic of chronic in injury in response to diverse pathogens. Staphylococcus aureus (S.aureus) is a frequent cause of mastitis in bovine and is prone to persistent infection. Diverse studies have shown MMPs/TIMPs and uPA system as a potent target for the treatment of fibrosis. However, pathogenesis of S. aureus-induced mammary fibrosis has not been completely defined.MethodsBMFBs treated with heat-inactivated S. aureus (10⁵, 10⁶, and 10⁸ CFU/mL) for 6, 12, 24, and 48 h. Total RNA and protein were isolated from the treatments and controls of BMFBs samples. MMP-1, MMP-2, MMP-3, MMP-9, MMP-13, TIMP-1, TIMP-2, COL Ⅰ, uPA, uPAR and PAI-1 gene and protein expression were examined by RT-qPCR and Western blot analysis. Gelatin zymography assay was performed to assess the levels of MMP-2 and MMP-9 enzyme secreted.ResultsBMFBs treated with heat-inactivated S. aureus increased mRNA and protein expression levels of MMP-1, MMP-2, MMP-3, MMP-9 and MMP-13, and heat-inactivated S. aureus induced TIMP-1, TIMP-2 and COL Ⅰ expression. There was a clear activation of MMP-2 in the presence of heat-inactivated S. aureus in the conditioned medium from the BMFBs, whereas MMP-9 was no significantly altered. Moreover, uPA system was activated in BMFBs to S. aureus.ConclusionActivation of the uPA system together with its impact on the MMPs levels could play a significant role in S. aureus-induced BMFBs with mechanism of ECM metabolism, MMPs/TIMPs and uPA system could participate in bovine mammary fibrosis.     

Homocysteine induces oxidative stress,inflammatory infiltration,fibrosis and reduces glycogen/glycoprotein content in liver of rats

Hyperhomocysteinemia has been related to various diseases, including homocystinuria, neurodegenerative and hepatic diseases. In the present study we initially investigated the effect of chronic homocysteine administration on some parameters of oxidative stress, named total radical-trapping antioxidant potential, total antioxidant reactivity, catalase activity, chemiluminescence, thiobarbituric acid-reactive substances, and total thiol content in liver of rats. We also performed histological analysis, evaluating steatosis, inflammatory infiltration, fibrosis, and glycogen/glycoprotein content in liver tissue sections from hyperhomocysteinemic rats. Finally, we evaluated the activities of aminotransferases in liver and plasma of hyperhomocysteinemic rats. Wistar rats received daily subcutaneous injection of Hcy from their 6th to their 28th day of life. Twelve hours after the last injection the rats were sacrificed, liver and plasma were collected. Hyperhomocysteinemia decreased antioxidant defenses and total thiol content, and increased lipid peroxidation in liver of rats, characterizing a reliable oxidative stress. Histological analysis indicated the presence of inflammatory infiltrate, fibrosis and reduced content of glycogen/glycoprotein in liver tissue sections from hyperhomocysteinemic rats. Aminotransferases activities were not altered by homocysteine. Our data showed a consistent profile of liver injury elicited by homocysteine, which could contribute to explain, at least in part, the mechanisms involved in human liver diseases associated to hyperhomocysteinemia.     

Multi-focal motor neuropathy: one treatment works but many uncertainties remain

The activity of a set of peptidases (proteases) involved in cancer progression is collectively known as the cancer ‘degradome’. Invasion and metastasis were initially considered as late events in cancer development and the processes in which proteases were involved. However, recent studies indicate that invasion and metastasis are not late events, but can occur during early stages as well. Moreover, other processes occurring in various stages of cancer progression are also protease-dependent, such as (upregulation of) cell proliferation, (downregulation of) apoptosis, involvement of white blood cells, angiogenesis and induction of multi-drug resistance. Proteolytic activity in tumours is regulated in a complex manner, as both genetically unstable cancer cells and stable stromal cells, such as fibroblasts, endothelial cells and inflammatory cells, are involved. In vitro studies and studies using animal models have clearly shown protease dependency of many processes in carcinogenesis. However, clinical trials using protease inhibitors have thus far been unsuccessful except for a few applications of matrix metalloprotease (MMP) inhibitors when used in combination with cytostatic anticancer agents and/or in the early stages of cancer. Antithrombotics, such as low-molecular-weight heparin and warfarin, were also successful in clinical trials, probably by interfering with proteases of the coagulation cascade. The two-way association between cancer and thrombosis has long been recognised in the clinic. The poor outcome of other clinical trials of protease inhibitors is probably due to the late stages of cancer of the patient populations included, and the limited understanding of the complex regulation and effects of the activity of the various proteases in tumours depending on, among others, tumour type and stage, interactions between the cancer cells, other cells and the extracellular matrix in tumours. Therefore, a better fundamental understanding of the proteolytic complexity in tumours is essential before clinical trials can be rationally designed. At present, antithrombotics, the urokinase-type plasminogen activator system, the membrane-bound membrane-type 1-MMP, cathepsin L and the proteasome seem the most promising candidates as targets for anticancer strategies in early stages of cancer in combination with cytotoxic drugs. Moreover, metronomic therapy is an attractive approach using low doses of inhibitors for prolonged periods of time without interruption to specifically target endothelial cells that are involved in angiogenesis.     

MMP-2、TIMP-1和TIMP-2在胚胎停育绒毛和蜕膜组织中的表达

目的:探讨MMP-2,TIMP-1和TIMP-2与胚胎停育的关系。方法:选取胚胎停止发育妇女为病例组,另设同期正常早孕自愿要求流产的妇女为对照组,分别留取其绒毛和蜕膜组织标本,采用半定量RT-PCR法对标本MMP-2,TIMP-1和TIMP-2 mRNA转录水平进行分析。结果:在绒毛标本中,MMP-2和TIMP-1 mRNA在病例组中表达水平显著低于对照组(P<0.01);而TIMP-2mRNA表达水平组间差异无统计学意义(P>0.05)。在蜕膜标本中,病例组TIMP-1 mRNA的表达水平显著低于对照组(P<0.01)。而MMP-2和TIMP-2 mRNA的表达水平组间差异无统计学意义(P>0.05)。结论:MMP-2,TIMP-1和TIMP-2的差异表达可能参与了胚胎停育的发生发展。     

Matrix metalloproteinase inhibitor properties of tetracyclines: Therapeutic potential in cardiovascular diseases

Matrix metalloproteinases (MMPs) are a family of proteases best known for their capacity to proteolyse several proteins of the extracellular matrix. Their increased activity contributes to the pathogenesis of several cardiovascular diseases. MMP-2 in particular is now considered to be also an important intracellular protease which has the ability to proteolyse specific intracellular proteins in cardiac muscle cells and thus reduce contractile function. Accordingly, inhibition of MMPs is a growing therapeutic aim in the treatment or prevention of various cardiovascular diseases. Tetracyclines, especially doxycycline, have been frequently used as important MMP inhibitors since they inhibit MMP activity independently of their antimicrobial properties. In this review we will focus on the intracellular actions of MMPs in some cardiovascular diseases including ischemia and reperfusion (I/R) injury, inflammatory heart diseases and septic shock; and explain how tetracyclines, as MMP inhibitors, have therapeutic actions to treat such diseases. We will also briefly discuss how MMPs can be intracellularly regulated and activated by oxidative stress, thus cleaving several important proteins inside cells. In addition to their potential therapeutic effects, MMP inhibitors may also be useful tools to understand the biological consequences of MMP activity and its respective extra- and intracellular effects.     

针刺对膝骨关节炎大鼠软骨基质金属蛋白酶及其抑制剂表达的影响

目的:探讨针刺治疗骨关节炎(OA)的作用机制.方法:选用SD雌性大鼠40只,采用随机数字表随机分为正常组、模型组、针刺组和药物组,每组10只.单侧后肢跟腱切除建立OA动物模型,针刺组采用电针大鼠"膝前"穴和"后三里"穴,药物组采用膝关节处涂擦扶他林乳剂进行治疗,正常组与模型组不予干预.采用免疫组化技术,观察各组关节软骨中基质金属蛋白酶-1(MMP-1)、基质金属蛋白酶-3(MMP-3)及组织金属蛋白酶抑制剂-1(TIMP-1)表达的特点,并比较各组间的差异.结果:4组组间差异非常显著,模型组、针刺组和药物组的MMP-1、MMP-3和TIMP-1表达均较正常组显著上调(均P<0.01);针刺组和药物组与模型组比较,均下调MMP-1和MMP-3,上调TIMP-1,差异均有统计学意义(均P<0.01);但针刺组MMP-1和MMP-3的表达显著低于药物组(均P<0.01),而TIMP-1的表达则显著高于药物组(P<0.01)o结论:针刺对OA软骨细胞MMP-1、MMP-3、TIMP-1的表达具有影响作用,下调MMP-1、MMP-3,上调TIMP-1,作用优于扶他林乳剂,说明针刺对OA软骨具有一定的保护作用.