Lysyl oxidase suppresses the inflammatory response in anterior cruciate ligament fibroblasts and promotes tissue regeneration by targeting myotrophin via the nuclear factor-kappa B pathway.

Anterior cruciate ligament (ACL) regeneration is severely affected by the injury-induced overexpression of matrix metalloproteinases (MMPs) and downregulation of lysyl oxidase (LOX). Previous studies have focused on how the expression of MMPs and downregulation of LOX are physiologically balanced at injured sites for regenerating the ACL tissue, but the role of LOX in regulating cellular functions has not been investigated yet. Herein, we conducted an in vitro cellular experiment and unexpectedly found that exogenous LOX inhibited the expression of MMPs and inflammatory factors and recovered the cell growth; thus, LOX strongly inhibited the tumor necrosis factor-alpha (TNF-α)-induced inflammatory responses.

Mechanical injury and IL-1β regulated LOXs and MMP-1, 2, 3 expression in ACL fibroblasts co-cultured with synoviocytes.

Objective: Interleukin (IL)-1β in the joint cavity increases to promote healing after anterior cruciate ligament (ACL) injury. Synovial tissue is a major joint microenvironmental regulator after ACL injury. The purpose of this study was to investigate the effects of synovial cells (SCs) on lysyl oxidase (LOX) and matrix metalloproteinase (MMP) production by ACL fibroblasts (ACLfs) in the presence of IL-1β.

Bay11-7082 facilitates wound healing by antagonizing mechanical injury- and TNF-α-induced expression of MMPs in posterior cruciate ligament.

To investigate the ability of synoviocytes (SCs) in regulating MMPs expression in the posterior cruciate ligament fibroblasts (PCLfs) after TNF-α treatment, to test whether a specific inflammation inhibitor Bay11-7082 can antagonize the expression of MMPs in PCLfs after injury. : The microenvironment of knee joint cavity after PCL injury was mimicked in an co-culture system. The effects of TNF-α treatment on the expression of MMPs in PCL fibroblasts (PCLfs) were studied.

Expression of LOXs and MMP-1, 2, 3 by ACL Fibroblasts and Synoviocytes Impact of Coculture and TNF-α.

This study aims to confirm the effects of synoviocytes (SCs) on regulating lysyl oxidases (LOXs) and matrix metalloproteinase (MMP)-1, 2, 3 in the normal and injured anterior cruciate ligament (ACL) fibroblasts response to tumor necrosis factor-α(TNF-α). The gene and protein expression levels of LOXs and MMP-1, 2, 3 in SCs cocultured ACL fibroblasts (ACLfs) induced by TNF-α and mechanical injury were analyzed by real-time polymerase chain reaction (PCR) and western bolting; the MMP-2 activity were analyzed by zymography. The results exhibited that TNF-α alone slightly downregulated the expressions of LOXs and upregulated the expression of MMP-1, 2, 3 in both normal and injured ACL fibroblasts.

Modulation of MMP-2 and MMP-9 through connected pathways and growth factors is critical for extracellular matrix balance of intra-articular ligaments.

The healing mechanism of cruciate ligaments is not well elucidated. Crosstalk between adjacent tissues in the knee joint plays an important role in wound healing and tissue regeneration, but the gelatinase modulation in posterior cruciate ligament fibroblasts (PCLfs) and synovial cells (SCs) based on co-culture is still elusive. The present study sought to systematically elucidate the gelatinase modulation in both PCLfs and SCs based on in vitro co-culture and in a rabbit PCL-injury model in vivo.

Influences of Tumor Necrosis Factor-α on Lysyl Oxidases and Matrix Metalloproteinases of Injured Anterior Cruciate Ligament and Medial Collateral Ligament Fibroblasts.

The anterior cruciate ligament (ACL) fails to heal after injury, even after a primary surgical attempt. In contrast, the medial collateral ligament (MCL) can heal relatively well and restore the full joint function. The difference in intrinsic properties of these ligament cells can be due to their different responses to their local factors.

Silk structure and degradation.

To investigate the structure of silk and its degradation properties, we have monitored the structure of silk using scanning electron microscopy and frozen sections. Raw silk and degummed raw silk were immersed in four types of degradation solutions for 156 d to observe their degradation properties. The subcutaneous implants in rats were removed after 7, 14, 56, 84, 129, and 145 d for frozen sectioning and subsequent staining with hematoxylin and eosin (H.

Differential expressions of the lysyl oxidase family and matrix metalloproteinases-1, 2, 3 in posterior cruciate ligament fibroblasts after being co-cultured with synovial cells.

Purpose: The adult human posterior cruciate ligament (PCL) has poor functional healing response. The synovial tissue, which surrounds the PCL ligament, might be the major regulator of the microenvironment in the joint cavity after PCL injury, thus affecting the healing process. Here we establish a novel co-culture system for PCL fibroblasts and synovial cells (SC) in vitro to explore the direct influence of paracrine on PCL cells by characterizing the different expressions of the lysyl oxidase family (LOXs) and matrix metalloproteinases (MMP-1, 2, 3), which respectively facilitate extracellular matrix (ECM) repair and degradation.

[Effect of titanium particles and TNF-alpha on the gene expression and activity of MMP-1, 2, 3 in human knee joint synovial cells].

This paper is aimed to investigate the effect of titanium (Ti) particles and tumor necrosis factor alpha (TNF-alpha) on the expressions of MMP-1, 2, 3 in human synovial cells, so as to explore the possible mechanism of osteolysis post-operation of metal-on-metal total joint arthroplasty in human synovial cells induced by Ti particles. In vitro cell cultures, human synovial cells were treated by Ti particles and/or TNF-alpha. The total RNA was isolated at 2 hours after the treatment.

[Gene expressions of LOXs and MMPs of the ACL fibroblasts cells co-cultured with synovial cells].

The progress of research on the the anterior cruciate ligament (ACL) wound healing demonstrates that the synovial tissue in the knee joint plays a very important role in the healing process of injured ACL. Therefore, the molecular response mechanisms of lysyl oxidase (LOX) and matrix metalloproteina (MMP) in normal/injured ACL fibroblast cells could be considered to perform the major analysis function of injured ACL healing mechanism. The mRNA expressions of LOXs and MMPs and the activity expressions of MMP-2 in ACL fibroblasts co-cultured with synovial cells were analyzed by quantitative real-time PCR and zymography.

TNF-α induced down-regulation of lysyl oxidase family in anterior cruciate ligament and medial collateral ligament fibroblasts.

Background: The lysyl oxidase (LOX) family has the capacity to catalyze the cross-linking of collagen and elastin, implicating its important fundamental role in injury healing. Tumor necrosis factor alpha (TNF-α) is considered to be an important chemical mediator in the acute inflammatory phase of the ligament injury. The role of the lysyl oxidase family induced by TNF-α in the knee ligaments' wound healing process is poorly understood.

TGF-beta1 induces the different expressions of lysyl oxidases and matrix metalloproteinases in anterior cruciate ligament and medial collateral ligament fibroblasts after mechanical injury.

The anterior cruciate ligament (ACL) is known to have a poor self-healing ability. In contrast, the medial collateral ligament (MCL) can heal relatively well and restore the joint function. Transforming growth factor-beta1 (TGF-β1) is considered to be an important chemical mediator in the wound healing of the ligaments.

Differential expressions of lysyl oxidase family in ACL and MCL fibroblasts after mechanical injury.

Lysyl oxidase (LOX) family has the capacity to catalyse the cross-linking of collagen and elastin, implicating its important fundamental roles in tissue development and injury healing. However, the variations in expression of the LOX family in the normal and injured anterior cruciate ligament (ACL) are not fully known. To better understand the role of LOX family in the self-healing inability mechanism of injured ACL, this study is to measure the LOX family's differential expressions in ACL and medial collateral ligament (MCL) fibroblasts after mechanical injury induced by using an equi-biaxial stretching chamber.

Regulation of the differentiation of mesenchymal stem cells in vitro and osteogenesis in vivo by microenvironmental modification of titanium alloy surfaces.

To mimic the extracellular microenvironment of bone, a bioactive multilayered structure of gelatin/chitosan pair, containing bone morphogenetic protein 2(BMP2) and fibronectin (FN), was constructed onto Ti6Al4V surface via a layer-by-layer assembly technique. The successful fabrication of multilayered structure was confirmed by contact angle measurement, field emission scanning electron microscopy (FE-SEM) and confocal laser scanning microscopy (CLSM), respectively. Bioactive BMP2 released in a sustained manner along with the degradation of multilayered structure.

Up-regulation expressions of lysyl oxidase family in Anterior Cruciate Ligament and Medial Collateral Ligament fibroblasts induced by Transforming Growth Factor-Beta 1.

Purpose: The lysyl oxidase (LOX) family plays a crucial role in the formation and stabilisation of extracellular matrix (ECM) by catalysing the cross-linking of collagen and elastin, implicating its important fundamental roles in injury healing. A high level of transforming growth factor-β(1) (TGF-β(1)) accompanies the inflammatory phase of an injury of the knee joint. Our purpose was to detect the expressions of the LOX family in anterior cruciate ligament (ACL) and medial collateral ligament (MCL) response to TGF-β(1).

Biophysical regulation of histone acetylation in mesenchymal stem cells.

Histone deacetylation and acetylation are catalyzed by histone deacetylase (HDAC) and histone acetyltransferase, respectively, which play important roles in the regulation of chromatin remodeling, gene expression, and cell functions. However, whether and how biophysical cues modulate HDAC activity and histone acetylation is not well understood. Here, we tested the hypothesis that microtopographic patterning and mechanical strain on the substrate regulate nuclear shape, HDAC activity, and histone acetylation.

The profile of MMP and TIMP in injured rat ACL.

Human anterior cruciate ligament (ACL) has poor healing ability after injury. The devastating effects of matrix metalloproteinases (MMPs) excess expression are regarded as the main reason. Tissue inhibitor metalloproteinases (TIMPs) may be independent of MMPs inhibition.

Differential MMP-2 activity induced by mechanical compression and inflammatory factors in human synoviocytes.

The anterior cruciate ligament, posterior cruciate ligament, cartilage and meniscus in human knee joint have poor healing ability. Accumulation of MMPs in the joint fluids due to knee injury has been considered as the main reason. Our previous experiments showed that synovium may be the major regulator of MMPs in joint cavity after injury.

[Advance of researches in nitric oxide biological function on wound repair].

Nitric oxide (NO) is a short-life free radical that acts as the small biological molecule, and exists in body extensively. Since its discovery over 20 years ago, NO has been found to play an important regulation role in angiogenesis, nerve and immune system. The subsequent studies also showed that NO exerted an important biological action in wound repairing and healing, which involved in the following phases of wound repair, inflammation, cell proliferation, matrix deposition and remodeling.

Targeting eradication of malignant cells derived from human bone marrow mesenchymal stromal cells.

Human bone marrow mesenchymal stromal cells (hBMSC) have been shown to participate in malignant transformation. However, hampered by the low frequency of malignant transformation of hBMSC, we do not yet know how to prevent malignant transformation of implanted hBMSC. In this study, in order to establish a model for the eradication of hBMSC-derived malignant cells, a gene fusion consisting of a human telomerase (hTERT) promoter modified with both c-Myc and myeloid zinc finger protein2 (MZF-2) binding elements and followed by the E.

Surface engineering of titanium with potassium hydroxide and its effects on the growth behavior of mesenchymal stem cells.

To improve the corrosion resistance and biological performance of commercially pure titanium (cp-Ti) substrates, potassium hydroxide was employed to modify the surfaces of titanium substrates, followed by biomimetic deposition of apatite on the substrates in a simulated body fluid. The morphologies of native and treated titanium substrates were characterized by field emission scanning electron microscopy (FE-SEM). Treatment with potassium hydroxide led to the formation of intermediate layers of potassium titanate on the surfaces of titanium substrates, while apatite was subsequently deposited onto the intermediate layer.

Coordinated expression of MMPs and TIMPs in rat knee intra-articular tissues after ACL injury.

Anterior cruciate ligament (ACL) has poor healing ability and an injured ACL would induce the degeneration of other intra-articular connective tissues. However, the coordinated expression and activities of matrix metalloproteinase (MMPs) in intra-articular tissues induced by ACL rupture were poorly understood. With a rat ACL rotating injury model, we found that after ACL injury, the mRNA levels of MMP-13, TIMP-1, and CD147 were significantly elevated in ACL, posterior cruciate ligament (PCL), synovium, meniscus, and cartilage.

Differential expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in anterior cruciate ligament and medial collateral ligament fibroblasts after a mechanical injury: involvement of the p65 subunit of NF-kappaB.

The anterior cruciate ligament (ACL) is known to have a poor healing ability, especially in comparison with the medial collateral ligament, which can heal relatively well. In this study, we detected significant increases in the mRNA levels of multiple matrix metalloproteinases (MMPs) (MMP-1, -2, -7, -9, -11, -14, -17, -21, -23A, -24, -25, -27, and -28) and tissue inhibitors of metalloproteinases (TIMPs) (TIMP-1, -2, -3, and -4) in ACL fibroblasts after an in vitro injury with an equi-biaxial stretch chamber. However, only some MMPs (MMP-7, -9, -14, -21, and -24) showed increases in injured medial collateral ligament fibroblasts, and to a much lesser degree than that observed in the injured ACL fibroblasts.

Oxidized low-density lipoprotein (Ox-LDL) impacts on erythrocyte viscoelasticity and its molecular mechanism.

The oxidized low-density lipoprotein (Ox-LDL) plays an important role in atherosclerosis, yet it remains unclear if it damages circulating erythrocytes. In this study, erythrocyte deformability and its membrane proteins after Ox-LDL incubations are investigated by micropipette aspiration, thiol radical measurement, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Results show that Ox-LDL incubation reduces the erythrocyte deformability, decreases free thiol radical contents in erythrocytes, and induces the cross-linking among membrane proteins.

Mechanical stretch regulates the expression of matrix metalloproteinase in rheumatoid arthritis fibroblast-like synoviocytes.

Mechanical stretch plays a crucial role in articular joints. In rheumatoid arthritis (RA), it is well known that fibroblast-like synoviocytes (FLS) produce matrix metalloproteinases (MMPs), resulting in local invasion into and degradation of bone and cartilage. We sought to examine whether mechanical stretch regulates the expression and underlying signal pathways of MMP secretion (MMP-1, -3, -13) in RA-FLS.