Comparing effects of perfusion and hydrostatic pressure on gene profiles of human chondrocyte.

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Zhu, Ge; Mayer-Wagner, Susanne; Schröder, Christian; Woiczinski, Matthias; Blum, Helmut; Lavagi, Ilaria; Krebs, Stefan; Redeker, Julia I; Hölzer, Andreas; Jansson, Volkmar; Betz, Oliver; Müller, Peter E

2015-09-20

Hydrostatic pressure and perfusion have been shown to regulate the chondrogenic potential of articular chondrocytes. In order to compare the effects of hydrostatic pressure plus perfusion (HPP) and perfusion (P) we investigated the complete gene expression profiles of human chondrocytes under HPP and P. A simplified bioreactor was constructed to apply loading (0.1 MPa for 2 h) and perfusion (2 ml) through the same piping by pressurizing the medium directly. High-density monolayer cultures of human chondrocytes were exposed to HPP or P for 4 days. Controls (C) were maintained in static cultures. Gene expression was evaluated by sequencing (RNAseq) and quantitative real-time PCR analysis. Both treatments changed gene expression levels of human chondrocytes significantly. Specifically, HPP and P increased COL2A1 expression and decreased COL1A1 and MMP-13 expression. Despite of these similarities, RNAseq revealed a list of cartilage genes including ACAN, ITGA10 and TNC, which were differentially expressed by HPP and P. Of these candidates, adhesion related molecules were found to be upregulated in HPP. Both HPP and P treatment had beneficial effects on chondrocyte differentiation and decreased catabolic enzyme expression. The study provides new insight into how hydrostatic pressure and perfusion enhance cartilage differentiation and inhibit catabolic effects. Copyright © 2015 Elsevier B.V. All rights reserved.

Nicotine promotes proliferation and collagen synthesis of chondrocytes isolated from normal human and osteoarthritis patients.

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Ying, Xiaozhou; Cheng, Shaowen; Shen, Yue; Cheng, Xiaojie; An Rompis, Ferdinand; Wang, Wei; Lin, Zhongqin; Chen, Qingyu; Zhang, Wei; Kou, Dongquan; Peng, Lei; Tian, Xin Qiao; Lu, Chuan Zhu

2012-01-01

The aims of the study were to show the direct effect of nicotine with different concentrations (0, 25, 50, and 100 ng/ml) on chondrocytes isolated from normal human and osteoarthritis patients, respectively. Microscopic observation was performed during the culture with an inverted microscope. Methyl thiazolyl tetrazolium (MTT) assay method was adopted to observe the influence of nicotine on the proliferation of chondrocytes, and real-time PCR and ELISA were used to assay the mRNA and protein expression of type II collagen and aggrecan, respectively. We discovered that the OA chondrocytes were similar to fibroblasts in shape and grow slower than normal chondrocytes. The proliferation of the two kinds of chondrocytes was increased in a concentration-dependent manner and in a time-dependent manner (P<0.05). Also, we found that the mRNA level of type II collagen were upregulated under 25-100 ng/ml nicotine doses both in the two kinds of chondrocytes compared with control. The expression of protein levels of type II collagen were synthesized in line with the increase in mRNA. No effect was observed on aggrecan synthesis with any nicotine dose. We concluded that nicotine has the same effect on both chondrocytes, obtained either from osteoarthritis patients or from normal human, and the positive effect of smoking in OA may relate to the alteration in metabolism of chondrocytes.

Interleukin-1 Acts via the JNK-2 Signaling Pathway to Induce Aggrecan Degradation by Human Chondrocytes.

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Ismail, Heba M; Yamamoto, Kazuhiro; Vincent, Tonia L; Nagase, Hideaki; Troeberg, Linda; Saklatvala, Jeremy

2015-07-01

Aggrecan enables articular cartilage to bear load and resist compression. Aggrecan loss occurs early in osteoarthritis and rheumatoid arthritis and can be induced by inflammatory cytokines such as interleukin-1 (IL-1). IL-1 induces cleavage of specific aggrecans characteristic of the ADAMTS proteinases. The aim of this study was to identify the intracellular signaling pathways by which IL-1 causes aggrecan degradation by human chondrocytes and to investigate how aggrecanase activity is controlled by chondrocytes. We developed a cell-based assay combining small interfering RNA (siRNA)-induced knockdown with aggrecan degradation assays. Human articular chondrocytes were overlaid with bovine aggrecan after transfection with siRNAs against molecules of the IL-1 signaling pathway. After IL-1 stimulation, released aggrecan fragments were detected with AGEG and ARGS neoepitope antibodies. Aggrecanase activity and tissue inhibitor of metalloproteinases 3 levels were measured by enzyme-linked immunosorbent assay. Low-density lipoprotein receptor-related protein 1 (LRP-1) shedding was analyzed by Western blotting. ADAMTS-5 is a major aggrecanase in human chondrocytes, regulating aggrecan degradation in response to IL-1. The tumor necrosis factor receptor-associated 6 (TRAF-6)/transforming growth factor β-activated kinase 1 (TAK-1)/MKK-4 signaling axis is essential for IL-1-induced aggrecan degradation, while NF-κB is not. Of the 3 MAPKs (ERK, p38, and JNK), only JNK-2 showed a significant role in aggrecan degradation. Chondrocytes constitutively secreted aggrecanase, which was continuously endocytosed by LRP-1, keeping the extracellular level of aggrecanase low. IL-1 induced aggrecanase activity in the medium in a JNK-2-dependent manner, possibly by reducing aggrecanase endocytosis, because IL-1 caused JNK-2-dependent shedding of LRP-1. The signaling axis TRAF-6/TAK-1/MKK-4/JNK-2 mediates IL-1-induced aggrecanolysis. The level of aggrecanase is controlled by its

Effects of tofacitinib on nucleic acid metabolism in human articular chondrocytes.

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Koizumi, Hideki; Arito, Mitsumi; Endo, Wataru; Kurokawa, Manae S; Okamoto, Kazuki; Omoteyama, Kazuki; Suematsu, Naoya; Beppu, Moroe; Kato, Tomohiro

2015-07-01

In our previous screening of chondrocyte protein profiles, the amount of adenosine monophosphate deaminase (AMPD) 2 was found to be decreased by tofacitinib. Extending the study, here we confirmed the decrease of AMPD2 by tofacitinib and further investigated effects of tofacitinib on purine nucleotide metabolism. Human articular chondrocytes and a chondrosarcoma cell line: OUMS-27 were stimulated with tofacitinib. Then the levels of AMPD2 and its related enzymes were investigated by Western blot. The levels of AMP and adenosine were assessed by mass spectrometry. We confirmed the significant decrease of AMPD2 by tofacitinib in chondrocytes (p = 0.025). The levels of adenosine kinase and 5'-nucleotidase were decreased in chondrocytes, although they did not meet statistical significance (p = 0.067 and p = 0.074, respectively). The results from OUMS-27 were similar to those from the chondrocytes. The cellular adenosine levels were significantly decreased by tofacitinib in OUMS-27 (p = 0.014). The cellular AMP levels were increased, although they did not meet statistical significance in OUMS-27 (p = 0.066). Our data indicate that tofacitinib increases the cellular levels of adenosine, which is known to have anti-inflammatory activity, through the downregulation of AMPD2. This would be a novel functional aspect of tofacitinib.

Nanosized fibers' effect on adult human articular chondrocytes behavior

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Stenhamre, Hanna [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Thorvaldsson, Anna, E-mail: anna.thorvaldsson@swerea.se [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Swerea IVF, Mölndal (Sweden); Enochson, Lars [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Walkenström, Pernilla [Swerea IVF, Mölndal (Sweden); Lindahl, Anders [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Brittberg, Mats [Cartilage Research Unit, University of Gothenburg, Department Orthopaedics, Kungsbacka Hospital, Kungsbacka (Sweden); Gatenholm, Paul [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden)

2013-04-01

Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. - Highlights: ► Chondrocyte behavior in nanofiber-coated microfiber versus microfiber scaffolds ► High porosity (> 90%) and large pore sizes (a few hundred μm) of nanofibrous scaffolds ► Proliferation enhanced by presence of nanofibers ► Differentiation not significantly affected ► Cell attachment improved in presence of both nanofibers and serum.

Nitric oxide from both exogenous and endogenous sources activates mitochondria-dependent events and induces insults to human chondrocytes.

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Wu, Gong-Jhe; Chen, Tyng-Guey; Chang, Huai-Chia; Chiu, Wen-Ta; Chang, Chia-Chen; Chen, Ruei-Ming

2007-08-15

During inflammation, overproduction of nitric oxide (NO) can damage chondrocytes. In this study, we separately evaluated the toxic effects of exogenous and endogenous NO on human chondrocytes and their possible mechanisms. Human chondrocytes were exposed to sodium nitroprusside (SNP), an NO donor, or a combination of lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) as the exogenous and endogenous sources of NO, respectively. Administration of SNP or a combination of LPS and IFN-gamma in human chondrocytes increased cellular NO levels but decreased cell viability. Exposure to exogenous or endogenous NO significantly induced apoptosis of human chondrocytes. When treated with exogenous or endogenous NO, the mitochondrial membrane potential time-dependently decreased. Exposure to exogenous or endogenous NO significantly enhanced cellular reactive oxygen species (ROS) and cytochrome c (Cyt c) levels. Administration of exogenous or endogenous NO increased caspase-3 activity and consequently induced DNA fragmentation. Suppression of caspase-3 activation by Z-DEVD-FMK decreased NO-induced DNA fragmentation and cell apoptosis. Similar to SNP, exposure of human chondrocytes to S-nitrosoglutathione (GSNO), another NO donor, caused significant increases in Cyt c levels, caspase-3 activity, and DNA fragmentation, and induced cell apoptosis. Pretreatment with N-monomethyl arginine (NMMA), an inhibitor of NO synthase, significantly decreased cellular NO levels, and lowered endogenous NO-induced alterations in cellular Cyt c amounts, caspase-3 activity, DNA fragmentation, and cell apoptosis. Results of this study show that NO from exogenous and endogenous sources can induce apoptotic insults to human chondrocytes via a mitochondria-dependent mechanism.

Acquiring Chondrocyte Phenotype from Human Mesenchymal Stem Cells under Inflammatory Conditions

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Masahiro Kondo

2014-11-01

Full Text Available An inflammatory milieu breaks down the cartilage matrix and induces chondrocyte apoptosis, resulting in cartilage destruction in patients with cartilage degenerative diseases, such as rheumatoid arthritis or osteoarthritis. Because of the limited regenerative ability of chondrocytes, defects in cartilage are irreversible and difficult to repair. Mesenchymal stem cells (MSCs are expected to be a new tool for cartilage repair because they are present in the cartilage and are able to differentiate into multiple lineages of cells, including chondrocytes. Although clinical trials using MSCs for patients with cartilage defects have already begun, its efficacy and repair mechanisms remain unknown. A PubMed search conducted in October 2014 using the following medical subject headings (MeSH terms: mesenchymal stromal cells, chondrogenesis, and cytokines resulted in 204 articles. The titles and abstracts were screened and nine articles relevant to “inflammatory” cytokines and “human” MSCs were identified. Herein, we review the cell biology and mechanisms of chondrocyte phenotype acquisition from human MSCs in an inflammatory milieu and discuss the clinical potential of MSCs for cartilage repair.

Carnosol Inhibits Pro-Inflammatory and Catabolic Mediators of Cartilage Breakdown in Human Osteoarthritic Chondrocytes and Mediates Cross-Talk between Subchondral Bone Osteoblasts and Chondrocytes.

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Christelle Sanchez

Full Text Available The aim of this work was to evaluate the effects of carnosol, a rosemary polyphenol, on pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes and via bone-cartilage crosstalk.Osteoarthritic (OA human chondrocytes were cultured in alginate beads for 4 days in presence or absence of carnosol (6 nM to 9 μM. The production of aggrecan, matrix metalloproteinase (MMP-3, tissue inhibitor of metalloproteinase (TIMP-1, interleukin (IL-6 and nitric oxide (NO and the expression of type II collagen and ADAMTS-4 and -5 were analyzed. Human osteoblasts from sclerotic (SC or non-sclerotic (NSC subchondral bone were cultured for 3 days in presence or absence of carnosol before co-culture with chondrocytes. Chondrocyte gene expression was analyzed after 4 days of co-culture.In chondrocytes, type II collagen expression was significantly enhanced in the presence of 3 μM carnosol (p = 0.008. MMP-3, IL-6, NO production and ADAMTS-4 expression were down-regulated in a concentration-dependent manner by carnosol (p<0.01. TIMP-1 production was slightly increased at 3 μM (p = 0.02 and ADAMTS-5 expression was decreased from 0.2 to 9 μM carnosol (p<0.05. IL-6 and PGE2 production was reduced in the presence of carnosol in both SC and NSC osteoblasts while alkaline phosphatase activity was not changed. In co-culture experiments preincubation of NSC and SC osteoblasts wih carnosol resulted in similar effects to incubation with anti-IL-6 antibody, namely a significant increase in aggrecan and decrease in MMP-3, ADAMTS-4 and -5 gene expression by chondrocytes.Carnosol showed potent inhibition of pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes. Inhibition of matrix degradation and enhancement of formation was observed in chondrocytes cocultured with subchondral osteoblasts preincubated with carnosol indicating a cross-talk between these two cellular compartments, potentially mediated via inhibition of IL-6 in

Topographic variation in redifferentiation capacity of chondrocytes in the adult human knee joint.

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Stenhamre, H; Slynarski, K; Petrén, C; Tallheden, T; Lindahl, A

2008-11-01

The aim of this study was to investigate the topographic variation in matrix production and cell density in the adult human knee joint. Additionally, we have examined the redifferentiation potential of chondrocytes expanded in vitro from the different locations. Full thickness cartilage-bone biopsies were harvested from seven separate anatomical locations of healthy knee joints from deceased adult human donors. Chondrocytes were isolated, expanded in vitro and redifferentiated in a pellet mass culture. Biochemical analysis of total collagen, proteoglycans and cellular content as well as histology and immunohistochemistry were performed on biopsies and pellets. In the biochemical analysis of the biopsies, we found lower proteoglycan to collagen (GAG/HP) ratio in the non-weight bearing (NWB) areas compared to the weight bearing (WB) areas. The chondrocytes harvested from different locations in femur showed a significantly better attachment and proliferation ability as well as good post-expansion chondrogenic capacity in pellet mass culture compared with the cells harvested from tibia. These results demonstrate that there are differences in extra cellular content within the adult human knee in respect to GAG/HP ratio. Additionally, the data show that clear differences between chondrocytes harvested from femur and tibia from healthy human knee joints exist and that the differences are not completely abolished during the process of de- and redifferentiation. These findings emphasize the importance of the understanding of topographic variation in articular cartilage biology when approaching new cartilage repair strategies.

Culture temperature affects human chondrocyte messenger RNA expression in monolayer and pellet culture systems.

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Ito, Akira; Nagai, Momoko; Tajino, Junichi; Yamaguchi, Shoki; Iijima, Hirotaka; Zhang, Xiangkai; Aoyama, Tomoki; Kuroki, Hiroshi

2015-01-01

Cell-based therapy has been explored for articular cartilage regeneration. Autologous chondrocyte implantation is a promising cell-based technique for repairing articular cartilage defects. However, there are several issues such as chondrocyte de-differentiation. While numerous studies have been designed to overcome some of these issues, only a few have focused on the thermal environment that can affect chondrocyte metabolism and phenotype. In this study, the effects of different culture temperatures on human chondrocyte metabolism- and phenotype-related gene expression were investigated in 2D and 3D environments. Human chondrocytes were cultured in a monolayer or in a pellet culture system at three different culture temperatures (32°C, 37°C, and 41°C) for 3 days. The results showed that the total RNA level, normalized to the threshold cycle value of internal reference genes, was higher at lower temperatures in both culture systems. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and citrate synthase (CS), which are involved in glycolysis and the citric acid cycle, respectively, were expressed at similar levels at 32°C and 37°C in pellet cultures, but the levels were significantly lower at 41°C. Expression of the chondrogenic markers, collagen type IIA1 (COL2A1) and aggrecan (ACAN), was higher at 37°C than at 32°C and 41°C in both culture systems. However, this phenomenon did not coincide with SRY (sex-determining region Y)-box 9 (SOX9), which is a fundamental transcription factor for chondrogenesis, indicating that a SOX9-independent pathway might be involved in this phenomenon. In conclusion, the expression of chondrocyte metabolism-related genes at 32°C was maintained or enhanced compared to that at 37°C. However, chondrogenesis-related genes were further induced at 37°C in both culture systems. Therefore, manipulating the culture temperature may be an advantageous approach for regulating human chondrocyte metabolic activity and chondrogenesis.

Culture temperature affects human chondrocyte messenger RNA expression in monolayer and pellet culture systems.

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Akira Ito

Full Text Available Cell-based therapy has been explored for articular cartilage regeneration. Autologous chondrocyte implantation is a promising cell-based technique for repairing articular cartilage defects. However, there are several issues such as chondrocyte de-differentiation. While numerous studies have been designed to overcome some of these issues, only a few have focused on the thermal environment that can affect chondrocyte metabolism and phenotype. In this study, the effects of different culture temperatures on human chondrocyte metabolism- and phenotype-related gene expression were investigated in 2D and 3D environments. Human chondrocytes were cultured in a monolayer or in a pellet culture system at three different culture temperatures (32°C, 37°C, and 41°C for 3 days. The results showed that the total RNA level, normalized to the threshold cycle value of internal reference genes, was higher at lower temperatures in both culture systems. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH and citrate synthase (CS, which are involved in glycolysis and the citric acid cycle, respectively, were expressed at similar levels at 32°C and 37°C in pellet cultures, but the levels were significantly lower at 41°C. Expression of the chondrogenic markers, collagen type IIA1 (COL2A1 and aggrecan (ACAN, was higher at 37°C than at 32°C and 41°C in both culture systems. However, this phenomenon did not coincide with SRY (sex-determining region Y-box 9 (SOX9, which is a fundamental transcription factor for chondrogenesis, indicating that a SOX9-independent pathway might be involved in this phenomenon. In conclusion, the expression of chondrocyte metabolism-related genes at 32°C was maintained or enhanced compared to that at 37°C. However, chondrogenesis-related genes were further induced at 37°C in both culture systems. Therefore, manipulating the culture temperature may be an advantageous approach for regulating human chondrocyte metabolic activity and

Long Intergenic Noncoding RNAs Mediate the Human Chondrocyte Inflammatory Response and Are Differentially Expressed in Osteoarthritis Cartilage.

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Pearson, Mark J; Philp, Ashleigh M; Heward, James A; Roux, Benoit T; Walsh, David A; Davis, Edward T; Lindsay, Mark A; Jones, Simon W

2016-04-01

To identify long noncoding RNAs (lncRNAs), including long intergenic noncoding RNAs (lincRNAs), antisense RNAs, and pseudogenes, associated with the inflammatory response in human primary osteoarthritis (OA) chondrocytes and to explore their expression and function in OA. OA cartilage was obtained from patients with hip or knee OA following joint replacement surgery. Non-OA cartilage was obtained from postmortem donors and patients with fracture of the neck of the femur. Primary OA chondrocytes were isolated by collagenase digestion. LncRNA expression analysis was performed by RNA sequencing (RNAseq) and quantitative reverse transcriptase-polymerase chain reaction. Modulation of lncRNA chondrocyte expression was achieved using LNA longRNA GapmeRs (Exiqon). Cytokine production was measured with Luminex. RNAseq identified 983 lncRNAs in primary human hip OA chondrocytes, 183 of which had not previously been identified. Following interleukin-1β (IL-1β) stimulation, we identified 125 lincRNAs that were differentially expressed. The lincRNA p50-associated cyclooxygenase 2-extragenic RNA (PACER) and 2 novel chondrocyte inflammation-associated lincRNAs (CILinc01 and CILinc02) were differentially expressed in both knee and hip OA cartilage compared to non-OA cartilage. In primary OA chondrocytes, these lincRNAs were rapidly and transiently induced in response to multiple proinflammatory cytokines. Knockdown of CILinc01 and CILinc02 expression in human chondrocytes significantly enhanced the IL-1-stimulated secretion of proinflammatory cytokines. The inflammatory response in human OA chondrocytes is associated with widespread changes in the profile of lncRNAs, including PACER, CILinc01, and CILinc02. Differential expression of CILinc01 and CIinc02 in hip and knee OA cartilage, and their role in modulating cytokine production during the chondrocyte inflammatory response, suggest that they may play an important role in mediating inflammation-driven cartilage degeneration in

In-vitro chondrogenic potential of synovial stem cells and chondrocytes allocated for autologous chondrocyte implantation

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Kubosch, Eva Johanna; Heidt, Emanuel; Niemeyer, Philipp

2017-01-01

Purpose: The use of passaged chondrocytes is the current standard for autologous chondrocyte implantation (ACI). De-differentiation due to amplification and donor site morbidity are known drawbacks highlighting the need for alternative cell sources. Methods: Via clinically validated flow cytometry...... analysis, we compared the expression of human stem cell and cartilage markers (collagen type 2 (Col2), aggrecan (ACAN), CD44) of chondrocytes (CHDR), passaged chondrocytes for ACI (CellGenix™), bone marrow derived mesenchymal stem cells (BMSC), and synovial derived stem cells (SDSC). Results: Primary...

Human IGF-I propeptide A promotes articular chondrocyte biosynthesis and employs glycosylation-dependent heparin binding.

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Shi, Shuiliang; Kelly, Brian J; Wang, Congrong; Klingler, Ken; Chan, Albert; Eckert, George J; Trippel, Stephen B

2018-03-01

Insulin-like growth factor I (IGF-I) is a key regulator of chondrogenesis, but its therapeutic application to articular cartilage damage is limited by rapid elimination from the repair site. The human IGF-I gene gives rise to three IGF-I propeptides (proIGF-IA, proIGF-IB and proIGF-IC) that are cleaved to create mature IGF-I. In this study, we elucidate the processing of IGF-I precursors by articular chondrocytes, and test the hypotheses that proIGF-I isoforms bind to heparin and regulate articular chondrocyte biosynthesis. Human IGF-I propeptides and mutants were overexpressed in bovine articular chondrocytes. IGF-I products were characterized by ELISA, western blot and FPLC using a heparin column. The biosynthetic activity of IGF-I products on articular chondrocytes was assayed for DNA and glycosaminoglycan that the cells produced. Secreted IGF-I propeptides stimulated articular chondrocyte biosynthetic activity to the same degree as mature IGF-I. Of the three IGF-I propeptides, only one, proIGF-IA, strongly bound to heparin. Interestingly, heparin binding of proIGF-IA depended on N-glycosylation at Asn92 in the EA peptide. To our knowledge, this is the first demonstration that N-glycosylation determines the binding of a heparin-binding protein to heparin. The biosynthetic and heparin binding abilities of proIGF-IA, coupled with its generation of IGF-I, suggest that proIGF-IA may have therapeutic value for articular cartilage repair. These data identify human pro-insulin-like growth factor IA as a bifunctional protein. Its combined ability to bind heparin and augment chondrocyte biosynthesis makes it a promising therapeutic agent for cartilage damage due to trauma and osteoarthritis. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of Four Protocols to Generate Chondrocyte-Like Cells from Human Induced Pluripotent Stem Cells (hiPSCs).

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Suchorska, Wiktoria Maria; Augustyniak, Ewelina; Richter, Magdalena; Trzeciak, Tomasz

2017-04-01

Stem cells (SCs) are a promising approach to regenerative medicine, with the potential to treat numerous orthopedic disorders, including osteo-degenerative diseases. The development of human-induced pluripotent stem cells (hiPSCs) has increased the potential of SCs for new treatments. However, current methods of differentiating hiPSCs into chondrocyte-like cells are suboptimal and better methods are needed. The aim of the present study was to assess four different chondrogenic differentiation protocols to identify the most efficient method of generating hiPSC-derived chondrocytes. For this study, hiPSCs were obtained from primary human dermal fibroblasts (PHDFs) and differentiated into chondrocyte-like cells using four different protocols: 1) monolayer culture with defined growth factors (GF); 2) embryoid bodies (EBs) in a chondrogenic medium with TGF-β3 cells; 3) EBs in chondrogenic medium conditioned with human chondrocytes (HC-402-05a cell line) and 4) EBs in chondrogenic medium conditioned with human chondrocytes and supplemented with TGF-β3. The cells obtained through these four protocols were evaluated and compared at the mRNA and protein levels. Although chondrogenic differentiation of hiPSCs was successfully achieved with all of these protocols, the two fastest and most cost-effective methods were the monolayer culture with GFs and the medium conditioned with human chondrocytes. Both of these methods are superior to other available techniques. The main advantage of the conditioned medium is that the technique is relatively simple and inexpensive while the directed method (i.e., monolayer culture with GFs) is faster than any protocol described to date because it is does not require additional steps such as EB formation.

Isolation and characterization of human articular chondrocytes from surgical waste after total knee arthroplasty (TKA

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Jakob Naranda

2017-03-01

Full Text Available Background Cartilage tissue engineering is a fast-evolving field of biomedical engineering, in which the chondrocytes represent the most commonly used cell type. Since research in tissue engineering always consumes a lot of cells, simple and cheap isolation methods could form a powerful basis to boost such studies and enable their faster progress to the clinics. Isolated chondrocytes can be used for autologous chondrocyte implantation in cartilage repair, and are the base for valuable models to investigate cartilage phenotype preservation, as well as enable studies of molecular features, nature and scales of cellular responses to alterations in the cartilage tissue. Methods Isolation and consequent cultivation of primary human adult articular chondrocytes from the surgical waste obtained during total knee arthroplasty (TKA was performed. To evaluate the chondrogenic potential of the isolated cells, gene expression of collagen type 2 (COL2, collagen 1 (COL1 and aggrecan (ACAN was evaluated. Immunocytochemical staining of all mentioned proteins was performed to evaluate chondrocyte specific production. Results Cartilage specific gene expression of COL2 and ACAN has been shown that the proposed protocol leads to isolation of cells with a high chondrogenic potential, possibly even specific phenotype preservation up to the second passage. COL1 expression has confirmed the tendency of the isolated cells dedifferentiation into a fibroblast-like phenotype already in the second passage, which confirms previous findings that higher passages should be used with care in cartilage tissue engineering. To evaluate the effectiveness of our approach, immunocytochemical staining of the evaluated chondrocyte specific products was performed as well. Discussion In this study, we developed a protocol for isolation and consequent cultivation of primary human adult articular chondrocytes with the desired phenotype from the surgical waste obtained during TKA. TKA is a

Investigation of the direct effects of salmon calcitonin on human osteoarthritic chondrocytes

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Pedersen Christian

2010-04-01

Full Text Available Abstract Background Calcitonin has been demonstrated to have chondroprotective effects under pre-clinical settings. It is debated whether this effect is mediated through subchondral-bone, directly on cartilage or both in combination. We investigated possible direct effects of salmon calcitonin on proteoglycans and collagen-type-II synthesis in osteoarthritic (OA cartilage. Methods Human OA cartilage explants were cultured with salmon calcitonin [100 pM-100 nM]. Direct effects of calcitonin on articular cartilage were evaluated by 1 measurement of proteoglycan synthesis by incorporation of radioactive labeled 35SO4 [5 μCi] 2 quantification of collagen-type-II formation by pro-peptides of collagen type II (PIINP ELISA, 3 QPCR expression of the calcitonin receptor in OA chondrocytes using four individual primer pairs, 4 activation of the cAMP signaling pathway by EIA and, 5 investigations of metabolic activity by AlamarBlue. Results QPCR analysis and subsequent sequencing confirmed expression of the calcitonin receptor in human chondrocytes. All doses of salmon calcitonin significantly elevated cAMP levels (P 35SO4 incorporation, with a 96% maximal induction at 10 nM (P Conclusion Calcitonin treatment increased proteoglycan and collagen synthesis in human OA cartilage. In addition to its well-established effect on subchondral bone, calcitonin may prove beneficial to the management of joint diseases through direct effects on chondrocytes.

The Involvement of Mutual Inhibition of ERK and mTOR in PLCγ1-Mediated MMP-13 Expression in Human Osteoarthritis Chondrocytes

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Zejun Liu

2015-08-01

Full Text Available The issue of whether ERK activation determines matrix synthesis or degradation in osteoarthritis (OA pathogenesis currently remains controversial. Our previous study shows that PLCγ1 and mTOR are involved in the matrix metabolism of OA cartilage. Investigating the interplays of PLCγ1, mTOR and ERK in matrix degradation of OA will facilitate future attempts to manipulate ERK in OA prevention and therapy. Here, cultured human normal chondrocytes and OA chondrocytes were treated with different inhibitors or transfected with expression vectors, respectively. The levels of ERK, p-ERK, PLCγ1, p-PLCγ1, mTOR, p-mTOR and MMP-13 were then evaluated by Western blotting analysis. The results manifested that the expression level of ERK in human OA chondrocytes was lower than that in human normal articular chondrocytes, and the up-regulation of ERK could promote matrix synthesis, including the decrease in MMP-13 level and the increase in Aggrecan level in human OA chondrocytes. Furthermore, the PLCγ1/ERK axis and a mutual inhibition of mTOR and ERK were observed in human OA chondrocytes. Interestingly, activated ERK had no inhibitory effect on MMP-13 expression in PLCγ1-transformed OA chondrocytes. Combined with our previous study, the non-effective state of ERK activation by PLCγ1 on MMP-13 may be partly attributed to the inhibition of the PLCγ1/mTOR axis on the PLCγ1/ERK axis. Therefore, the study indicates that the mutual inhibition of ERK and mTOR is involved in PLCγ1-mediated MMP-13 expression in human OA chondrocytes, with important implication for the understanding of OA pathogenesis as well as for its prevention and therapy.

High seeding density of human chondrocytes in agarose produces tissue-engineered cartilage approaching native mechanical and biochemical properties.

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Cigan, Alexander D; Roach, Brendan L; Nims, Robert J; Tan, Andrea R; Albro, Michael B; Stoker, Aaron M; Cook, James L; Vunjak-Novakovic, Gordana; Hung, Clark T; Ateshian, Gerard A

2016-06-14

Animal cells have served as highly controllable model systems for furthering cartilage tissue engineering practices in pursuit of treating osteoarthritis. Although successful strategies for animal cells must ultimately be adapted to human cells to be clinically relevant, human chondrocytes are rarely employed in such studies. In this study, we evaluated the applicability of culture techniques established for juvenile bovine and adult canine chondrocytes to human chondrocytes obtained from fresh or expired osteochondral allografts. Human chondrocytes were expanded and encapsulated in 2% agarose scaffolds measuring ∅3-4mm×2.3mm, with cell seeding densities ranging from 15 to 90×10(6)cells/mL. Subsets of constructs were subjected to transient or sustained TGF-β treatment, or provided channels to enhance nutrient transport. Human cartilaginous constructs physically resembled native human cartilage, and reached compressive Young's moduli of up to ~250kPa (corresponding to the low end of ranges reported for native knee cartilage), dynamic moduli of ~950kPa (0.01Hz), and contained 5.7% wet weight (%/ww) of glycosaminoglycans (≥ native levels) and 1.5%/ww collagen. We found that the initial seeding density had pronounced effects on tissue outcomes, with high cell seeding densities significantly increasing nearly all measured properties. Transient TGF-β treatment was ineffective for adult human cells, and tissue construct properties plateaued or declined beyond 28 days of culture. Finally, nutrient channels improved construct mechanical properties, presumably due to enhanced rates of mass transport. These results demonstrate that our previously established culture system can be successfully translated to human chondrocytes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reconstruction of Hyaline Cartilage Deep Layer Properties in 3-Dimensional Cultures of Human Articular Chondrocytes.

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Nanduri, Vibudha; Tattikota, Surendra Mohan; T, Avinash Raj; Sriramagiri, Vijaya Rama Rao; Kantipudi, Suma; Pande, Gopal

2014-06-01

Articular cartilage (AC) injuries and malformations are commonly noticed because of trauma or age-related degeneration. Many methods have been adopted for replacing or repairing the damaged tissue. Currently available AC repair methods, in several cases, fail to yield good-quality long-lasting results, perhaps because the reconstructed tissue lacks the cellular and matrix properties seen in hyaline cartilage (HC). To reconstruct HC tissue from 2-dimensional (2D) and 3-dimensional (3D) cultures of AC-derived human chondrocytes that would specifically exhibit the cellular and biochemical properties of the deep layer of HC. Descriptive laboratory study. Two-dimensional cultures of human AC-derived chondrocytes were established in classical medium (CM) and newly defined medium (NDM) and maintained for a period of 6 weeks. These cells were suspended in 2 mm-thick collagen I gels, placed in 24-well culture inserts, and further cultured up to 30 days. Properties of chondrocytes, grown in 2D cultures and the reconstructed 3D cartilage tissue, were studied by optical and scanning electron microscopic techniques, immunohistochemistry, and cartilage-specific gene expression profiling by reverse transcription polymerase chain reaction and were compared with those of the deep layer of native human AC. Two-dimensional chondrocyte cultures grown in NDM, in comparison with those grown in CM, showed more chondrocyte-specific gene activity and matrix properties. The NDM-grown chondrocytes in 3D cultures also showed better reproduction of deep layer properties of HC, as confirmed by microscopic and gene expression analysis. The method used in this study can yield cartilage tissue up to approximately 1.6 cm in diameter and 2 mm in thickness that satisfies the very low cell density and matrix composition properties present in the deep layer of normal HC. This study presents a novel and reproducible method for long-term culture of AC-derived chondrocytes and reconstruction of cartilage

Biotechnological Chondroitin a Novel Glycosamminoglycan With Remarkable Biological Function on Human Primary Chondrocytes.

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Stellavato, Antonietta; Tirino, Virginia; de Novellis, Francesca; Della Vecchia, Antonella; Cinquegrani, Fabio; De Rosa, Mario; Papaccio, Gianpaolo; Schiraldi, Chiara

2016-09-01

Cartilage tissue engineering, with in vitro expansion of autologus chondrocytes, is a promising technique for tissue regeneration and is a new potential strategy to prevent and/or treat cartilage damage (e.g., osteoarthritis). The aim of this study was (i) to investigate and compare the effects of new biotechnological chondroitin (BC) and a commercial extractive chondroitin sulfate (CS) on human chondrocytes in vitro culture; (ii) to evaluate the anti-inflammatory effects of the innovative BC compared to extractive CS. A chondrogenic cell population was isolated from human nasoseptal cartilage and in vitro cultures were studied through time-lapse video microscopy (TLVM), immunohistochemical staining and cytometry. In order to investigate the effect of BC and CS on phenotype maintainance, chondrogenic gene expression of aggrecan (AGN), of the transcriptor factor SOX9, of the types I and II collagen (COL1A1 and COL1A2), were quantified through transcriptional and protein evaluation at increasing cultivation time and passages. In addition to resemble the osteoarthritis-like in vitro model, chondrocytes were treated with IL-1β and the anti-inflammatory activity of BC and CS was assessed using cytokines quantification by multiplex array. BC significantly enhances cell proliferation also preserving chondrocyte phenotype increasing type II collagen expression up to 10 days of treatment and reduces inflammatory response in IL-1β treated chondrocytes respect to CS treated cells. Our results, taken together, suggest that this new BC is of foremost importance in translational medicine because it can be applied in novel scaffolds and pharmaceutical preparations aiming at cartilage pathology treatments such as the osteoarthritis. J. Cell. Biochem. 117: 2158-2169, 2016. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.

Indian hedgehog signaling promotes chondrocyte differentiation in enchondral ossification in human cervical ossification of the posterior longitudinal ligament.

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Sugita, Daisuke; Yayama, Takafumi; Uchida, Kenzo; Kokubo, Yasuo; Nakajima, Hideaki; Yamagishi, Atsushi; Takeura, Naoto; Baba, Hisatoshi

2013-10-15

Histological, immunohistochemical, and immunoblot analyses of the expression of Indian hedgehog (Ihh) signaling in human cervical ossification of the posterior longitudinal ligament (OPLL). To examine the hypothesis that Ihh signaling in correlation with Sox9 and parathyroid-related peptide hormone (PTHrP) facilitates chondrocyte differentiation in enchondral ossification process in human cervical OPLL. In enchondral ossification, certain transcriptional factors regulate cell differentiation. OPLL is characterized by overexpression of these factors and disturbance of the normal cell differentiation process. Ihh signaling is essential for enchondral ossification, especially in chondrocyte hypertrophy. Samples of ossified ligaments were harvested from 45 patients who underwent anterior cervical decompressive surgery for symptomatic OPLL, and 6 control samples from patients with cervical spondylotic myelopathy/radiculopathy without OPLL. The harvested sections were stained with hematoxylin-eosin and toluidine blue, examined by transmission electron microscopy, and immunohistochemically stained for Ihh, PTHrP, Sox9, type X, XI collagen, and alkaline phosphatase. Immunoblot analysis was performed in cultured cells derived from the posterior longitudinal ligaments in the vicinity of the ossified plaque and examined for the expression of these factors. The ossification front in OPLL contained chondrocytes at various differentiation stages, including proliferating chondrocytes in fibrocartilaginous area, hypertrophic chondrocytes around the calcification front, and apoptotic chondrocytes near the ossified area. Immunoreactivity for Ihh and Sox9 was evident in proliferating chondrocytes and was strongly positive for PTHrP in hypertrophic chondrocytes. Mesenchymal cells with blood vessel formation were positive for Ihh, PTHrP, and Sox9. Cultured cells from OPLL tissues expressed significantly higher levels of Ihh, PTHrP, and Sox9 than those in non-OPLL cells. Our results

Differences in Cartilage-Forming Capacity of Expanded Human Chondrocytes From Ear and Nose and Their Gene Expression Profiles

NARCIS (Netherlands)

Hellingman, C.A.; Verwiel, E.T.P.; Slagt, I.; Koevoet, W.; Poublon, R.M.L.; Nolst-Trenite, G.J.; de Jong, R.J.B.; Jahr, H.; van Osch, G.J.V.M.

2011-01-01

The aim of this study was to evaluate the potential of culture-expanded human auricular and nasoseptal chondrocytes as cell source for regeneration of stable cartilage and to analyze the differences in gene expression profile of expanded chondrocytes from these specific locations. Auricular

Differences in cartilage-forming capacity of expanded human chondrocytes from ear and nose and their gene expression profiles

NARCIS (Netherlands)

Hellingman, Catharine A.; Verwiel, Eugène T. P.; Slagt, Inez; Koevoet, Wendy; Poublon, René M. L.; Nolst-Trenité, Gilbert J.; Baatenburg de Jong, Robert J.; Jahr, Holger; van Osch, Gerjo J. V. M.

2011-01-01

The aim of this study was to evaluate the potential of culture-expanded human auricular and nasoseptal chondrocytes as cell source for regeneration of stable cartilage and to analyze the differences in gene expression profile of expanded chondrocytes from these specific locations. Auricular

Human-like collagen/nano-hydroxyapatite scaffolds for the culture of chondrocytes

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Jia, Liping; Duan, Zhiguang [Shaanxi Key Laboratory of Degradable Biomedical Materials, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Shaanxi R and D Center of Biomaterials and Fermentation Engineering, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Fan, Daidi, E-mail: fandaidi@nwu.edu.cn [Shaanxi Key Laboratory of Degradable Biomedical Materials, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Shaanxi R and D Center of Biomaterials and Fermentation Engineering, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Mi, Yu; Hui, Junfeng [Shaanxi Key Laboratory of Degradable Biomedical Materials, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Shaanxi R and D Center of Biomaterials and Fermentation Engineering, Northwest University, 229 Taibai North Road, Xi' an, Shaanxi 710069 (China); Chang, Le [School of Chemical Engineering, Northwest University, Xi' an, Shaanxi 710069 (China)

2013-03-01

Three dimensional (3D) biodegradable porous scaffolds play a key role in cartilage tissue repair. Freeze-drying and cross-linking techniques were used to fabricate a 3D composite scaffold that combined the excellent biological characteristics of human-like collagen (HLC) and the outstanding mechanical properties of nano-hydroxyapatite (nHA). The scaffolds were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and compression tests, using Relive Registered-Sign Artificial Bone (RAB) scaffolds as a control. HLC/nHA scaffolds displayed homogeneous interconnected macroporous structure and could withstand a compression stress of 2.67 {+-} 0.37 MPa, which was higher than that of the control group. Rabbit chondrocytes were seeded on the composite porous scaffolds and cultured for 21 days. Cell/scaffold constructs were examined using SEM, histological procedures, and biochemical assays for cell proliferation and the production of glycosaminoglycans (GAGs). The results indicated that HLC/nHA porous scaffolds were capable of encouraging cell adhesion, homogeneous distribution and abundant GAG synthesis, and maintaining natural chondrocyte morphology compared to RAB scaffolds. In conclusion, the presented data warrants the further exploration of HLC/nHA scaffolds as a potential biomimetic platform for chondrocytes in cartilage tissue engineering. - Highlights: Black-Right-Pointing-Pointer Human-like collagen was first used to prepare cartilage tissue engineering scaffold. Black-Right-Pointing-Pointer Genipin, a natural biological cross-linking agent, was introduced to treat scaffold. Black-Right-Pointing-Pointer We chose market product as a control.

Chondrogenic differentiation of human articular chondrocytes differs in biodegradable PGA/PLA scaffolds

DEFF Research Database (Denmark)

Zwingmann, Joern; Mehlhorn, Alexander T; Südkamp, Norbert

2007-01-01

Cartilage tissue engineering is applied clinically to cover and regenerate articular cartilage defects. Two bioresorbable nonwoven scaffolds, polyglycolic acid (PGA) and poly(lactic-co-glycolic acid) (PLGA) (90/10 copolymer of L-lactide and glycolide), were seeded with human chondrocytes after in...

Bone marrow extract as a growth supplement for human iliac apophyseal chondrocyte culture

Directory of Open Access Journals (Sweden)

Balasubramanian Balakumar

2016-01-01

Full Text Available Background & objectives: Human bone marrow is rich in various growth factors which may support the chondrocyte growth. This study was conducted to compare the culture characteristics of human growth plate chondrocyte in foetal bovine serum (FBS and human autologous bone marrow extract (BME in monolayer culture. Methods: Iliac crest apophyseal cartilage was harvested from four donors, aged between two and nine years, undergoing hip surgery. Chondrocytes were propagated under two culture conditions, with 10 per cent FBS and 10 per cent autologous BME harvested from the same donors. Cells were harvested at 7, 14 and 21 days to assess viability, morphology, cell count and immunocytochemistry. Results: With an initial seeding density of 2500 cells/cm 2 , the average yield in monolayer cultured with FBS was 3.35 × 10 5 , 5.9 × 10 5 , 14.1 × 10 5 and BME was 0.66 × 10 5 , 1.57 × 10 5 and 3.48 × 10 5 at 7, 14 and 21 days, respectively. Viability was 98.21 per cent with FBS and 97.45 per cent with BME at 21 days. In BME supplemented cultures, hyaline phenotype was maintained up to 21 days. The yield was higher in the FBS supplemented group; however, the phenotype could not be maintained by the FBS group as long as BME group. Interpretation & conclusions: Autologous BME was found to be a safer alternative to FBS for human studies. BME could maintain the hyaline phenotype for a longer time. Ways to enhance the cell yield needs to be explored in future studies.

The synovial microenvironment of osteoarthritic joints alters RNA-seq expression profiles of human primary articular chondrocytes

Science.gov (United States)

Lewallen, Eric A.; Bonin, Carolina A.; Li, Xin; Smith, Jay; Karperien, Marcel; Larson, A. Noelle; Lewallen, David G.; Cool, Simon M.; Westendorf, Jennifer J.; Krych, Aaron J.; Leontovich, Alexey A.; Im, Hee-Jeong; van Wijnen, Andre J.

2018-01-01

Osteoarthritis (OA) is a disabling degenerative joint disease that prompts pain with limited treatment options. To permit early diagnosis and treatment of OA, a high resolution mechanistic understanding of human chondrocytes in normal and diseased states is necessary. In this study, we assessed the biological effects of OA-related changes in the synovial microenvironment on chondrocytes embedded within anatomically intact cartilage from joints with different pathological grades by next generation RNA-sequencing (RNA-seq). We determined the transcriptome of primary articular chondrocytes derived from pristine knees and ankles, as well as from joints affected by OA. The GALAXY bioinformatics platform was used to facilitate biological interpretations. Comparisons of patient samples by k-means, hierarchical clustering and principal component analysis reveal that primary chondrocytes exhibit OA grade-related differences in gene expression, including genes involved in cell-adhesion, ECM production and immune response. We conclude that diseased synovial microenvironments in joints with different histopathological OA grades directly alter gene expression in chondrocytes. One ramification of this finding is that sampling anatomically intact cartilage from OA joints is not an ideal source of healthy chondrocytes, nor should they be used to generate a normal baseline for the molecular characterization of diseased joints. PMID:27378743

Fluoroquinolone's effect on growth of human chondrocytes and chondrosarcomas. In vitro and in vivo correlation

DEFF Research Database (Denmark)

Multhaupt, H A; Alvarez, J C; Rafferty, P A

2001-01-01

Clinical and in vitro studies have demonstrated that fluoroquinolones are toxic to chondrocytes; however, the exact mechanism of fluoroquinolone arthropathy is unknown. We investigated the toxicity of ciprofloxacin on normal cartilage and on cartilaginous tumors. Normal human cartilage, enchondroma...... with use of conventional light microscopy, electron microscopy, and immunohistochemistry to identify extracellular matrix, cell proliferation, and apoptosis. Cultures of normal chondrocytes expressed type-II collagen. Electron microscopy revealed a large amount of glycogen in the cells; the presence of fat...... of vimentin filaments. The treated chondrocytes showed a decrease in cell proliferation, but there was no induction of apoptosis or effect on the expression of extracellular matrix proteins. Ciprofloxacin-treated chondrosarcoma cultures and tissue samples showed changes in cartilage matrix composition...

The Regulatory Role of Signaling Crosstalk in Hypertrophy of MSCs and Human Articular Chondrocytes

Directory of Open Access Journals (Sweden)

Leilei Zhong

2015-08-01

Full Text Available Hypertrophic differentiation of chondrocytes is a main barrier in application of mesenchymal stem cells (MSCs for cartilage repair. In addition, hypertrophy occurs occasionally in osteoarthritis (OA. Here we provide a comprehensive review on recent literature describing signal pathways in the hypertrophy of MSCs-derived in vitro differentiated chondrocytes and chondrocytes, with an emphasis on the crosstalk between these pathways. Insight into the exact regulation of hypertrophy by the signaling network is necessary for the efficient application of MSCs for articular cartilage repair and for developing novel strategies for curing OA. We focus on articles describing the role of the main signaling pathways in regulating chondrocyte hypertrophy-like changes. Most studies report hypertrophic differentiation in chondrogenesis of MSCs, in both human OA and experimental OA. Chondrocyte hypertrophy is not under the strict control of a single pathway but appears to be regulated by an intricately regulated network of multiple signaling pathways, such as WNT, Bone morphogenetic protein (BMP/Transforming growth factor-β (TGFβ, Parathyroid hormone-related peptide (PTHrP, Indian hedgehog (IHH, Fibroblast growth factor (FGF, Insulin like growth factor (IGF and Hypoxia-inducible factor (HIF. This comprehensive review describes how this intricate signaling network influences tissue-engineering applications of MSCs in articular cartilage (AC repair, and improves understanding of the disease stages and cellular responses within an OA articular joint.

THE EFFECT OF PIROXICAM ON THE METABOLISM OF ISOLATED HUMAN CHONDROCYTES

NARCIS (Netherlands)

BULSTRA, SK; KUIJER, R; BUURMAN, WA; TERWINDTROUWENHORST, E; GUELEN, PJM; VANDERLINDEN, AJ

The effect of piroxicam on the metabolism of healthy and osteoarthrotic (OA) chondrocytes was studied in vitro. The chondrocytes were obtained from five healthy, five moderately OA, and four severely OA hips or knees. The chondrocytes were cultured in a high-density, short-term in vitro model. In

Analysis of human articular chondrocyte CD44 isoform expression and function in health and disease.

Science.gov (United States)

Salter, D M; Godolphin, J L; Gourlay, M S; Lawson, M F; Hughes, D E; Dunne, E

1996-08-01

Interactions between articular chondrocytes and components of the extracellular matrix are of potential importance in the normal function of cartilage and in the pathophysiology of arthritis. Little is known of the basis of these interactions, but cell adhesive molecules such as CD44 are likely to be involved. Immunohistology using six well-characterized anti-CD44 monoclonal antibodies demonstrated standard CD44 isoform (CD44H) expression by all chondrocytes in normal and osteoarthrotic (OA) cartilage but absence of the CD44E variant. Polymerase chain reaction (PCR) of reverse transcribed mRNA from monolayer cultures of normal and OA chondrocytes using primer sequences which span the region containing variably spliced exons produced a predominant band representing the standard form of CD44, which lacks the variable exons 6-15 (v1-v10). No product was seen at the expected size of the epithelial variant of CD44 (CD44v8-10). Use of exon-specific primers, however, showed expression of variant exons resulting in multiple minor isoforms. Standard CD44 was also shown to be the predominantly expressed isoform identified by immunoprecipitation, but human articular chondrocytes did not adhere to hyaluronan in vitro. Chondrocyte CD44 may function as an adhesion receptor for other matrix molecules such as fibronectin or collagen.

BMP-2, hypoxia, and COL1A1/HtrA1 siRNAs favor neo-cartilage hyaline matrix formation in chondrocytes.

Science.gov (United States)

Ollitrault, David; Legendre, Florence; Drougard, Carole; Briand, Mélanie; Benateau, Hervé; Goux, Didier; Chajra, Hanane; Poulain, Laurent; Hartmann, Daniel; Vivien, Denis; Shridhar, Vijayalakshmi; Baldi, Alfonso; Mallein-Gerin, Frédéric; Boumediene, Karim; Demoor, Magali; Galera, Philippe

2015-02-01

Osteoarthritis (OA) is an irreversible pathology that causes a decrease in articular cartilage thickness, leading finally to the complete degradation of the affected joint. The low spontaneous repair capacity of cartilage prevents any restoration of the joint surface, making OA a major public health issue. Here, we developed an innovative combination of treatment conditions to improve the human chondrocyte phenotype before autologous chondrocyte implantation. First, we seeded human dedifferentiated chondrocytes into a collagen sponge as a scaffold, cultured them in hypoxia in the presence of a bone morphogenetic protein (BMP), BMP-2, and transfected them with small interfering RNAs targeting two markers overexpressed in OA dedifferentiated chondrocytes, that is, type I collagen and/or HtrA1 serine protease. This strategy significantly decreased mRNA and protein expression of type I collagen and HtrA1, and led to an improvement in the chondrocyte phenotype index of differentiation. The effectiveness of our in vitro culture process was also demonstrated in the nude mouse model in vivo after subcutaneous implantation. We, thus, provide here a new protocol able to favor human hyaline chondrocyte phenotype in primarily dedifferentiated cells, both in vitro and in vivo. Our study also offers an innovative strategy for chondrocyte redifferentiation and opens new opportunities for developing therapeutic targets.

Cell expansion of human articular chondrocytes on macroporous gelatine scaffolds-impact of microcarrier selection on cell proliferation

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Pettersson, Sofia; Kratz, Gunnar [Laboratory for Reconstructive Plastic Surgery, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Wetteroe, Jonas [Rheumatology/AIR, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Tengvall, Pentti, E-mail: sofia.pettersson@liu.se [Institute of Clinical Sciences, Department of Biomaterials, The Sahlgrenska Academy at University of Gothenburg, SE-405 30 Gothenburg (Sweden)

2011-12-15

This study investigates human chondrocyte expansion on four macroporous gelatine microcarriers (CultiSpher) differing with respect to two manufacturing processes-the amount of emulsifier used during initial preparation and the gelatine cross-linking medium. Monolayer-expanded articular chondrocytes from three donors were seeded onto the microcarriers and cultured in spinner flask systems for a total of 15 days. Samples were extracted every other day to monitor cell viability and establish cell counts, which were analysed using analysis of variance and piecewise linear regression. Chondrocyte densities increased according to a linear pattern for all microcarriers, indicating an ongoing, though limited, cell proliferation. A strong chondrocyte donor effect was seen during the initial expansion phase. The final cell yield differed significantly between the microcarriers and our results indicate that manufacturing differences affected chondrocyte densities at this point. Remaining cells stained positive for chondrogenic markers SOX-9 and S-100 but extracellular matrix formation was modest to undetectable. In conclusion, the four gelatine microcarriers supported chondrocyte adhesion and proliferation over a two week period. The best yield was observed for microcarriers produced with low emulsifier content and cross-linked in water and acetone. These results add to the identification of optimal biomaterial parameters for specific cellular processes and populations.

Three-dimensional scaffold-free fusion culture: the way to enhance chondrogenesis of in vitro propagated human articular chondrocytes

Directory of Open Access Journals (Sweden)

M. Lehmann

2013-11-01

Full Text Available Cartilage regeneration based on isolated and culture-expanded chondrocytes has been studied in various in vitro models, but the quality varies with respect to the morphology and the physiology of the synthesized tissues. The aim of our study was to promote in vitro chondrogenesis of human articular chondrocytes using a novel three-dimensional (3-D cultivation system in combination with the chondrogenic differentiation factors transforming growth factor beta 2 (TGF-b2 and L-ascorbic acid. Articular chondrocytes isolated from six elderly patients were expanded in monolayer culture. A single-cell suspension of the dedifferentiated chondrocytes was then added to agar-coated dishes without using any scaffold material, in the presence, or absence of TGF-b2 and/or L-ascorbic acid. Three-dimensional cartilage-like constructs, called single spheroids, and microtissues consisting of several spheroids fused together, named as fusions, were formed. Generated tissues were mainly characterized using histological and immunohistochemical techniques. The morphology of the in vitro tissues shared some similarities to native hyaline cartilage in regard to differentiated S100-positive chondrocytes within a cartilaginous matrix, with strong collagen type II expression and increased synthesis of proteoglycans. Finally, our innovative scaffold-free fusion culture technique supported enhanced chondrogenesis of human articular chondrocytes in vitro. These 3-D hyaline cartilage-like microtissues will be useful for in vitro studies of cartilage differentiation and regeneration, enabling optimization of functional tissue engineering and possibly contributing to the development of new approaches to treat traumatic cartilage defects or osteoarthritis.

Chondrocyte secreted CRTAC1: a glycosylated extracellular matrix molecule of human articular cartilage.

Science.gov (United States)

Steck, Eric; Bräun, Jessica; Pelttari, Karoliina; Kadel, Stephanie; Kalbacher, Hubert; Richter, Wiltrud

2007-01-01

Cartilage acidic protein 1 (CRTAC1), a novel human marker which allowed discrimination of human chondrocytes from osteoblasts and mesenchymal stem cells in culture was so far studied only on the RNA-level. We here describe its genomic organisation and detect a new brain expressed (CRTAC1-B) isoform resulting from alternate last exon usage which is highly conserved in vertebrates. In humans, we identify an exon sharing process with the neighbouring tail-to-tail orientated gene leading to CRTAC1-A. This isoform is produced by cultured human chondrocytes, localized in the extracellular matrix of articular cartilage and its secretion can be stimulated by BMP4. Of five putative O-glycosylation motifs in the last exon of CRTAC1-A, the most C-terminal one is modified according to exposure of serial C-terminal deletion mutants to the O-glycosylation inhibitor Benzyl-alpha-GalNAc. Both isoforms contain four FG-GAP repeat domains and an RGD integrin binding motif, suggesting cell-cell or cell-matrix interaction potential. In summary, CRTAC1 acquired an alternate last exon from the tail-to-tail oriented neighbouring gene in humans resulting in the glycosylated isoform CRTAC1-A which represents a new extracellular matrix molecule of articular cartilage.

High fat-diet and saturated fatty acid palmitate inhibits IGF-1 function in chondrocytes.

Science.gov (United States)

Nazli, S A; Loeser, R F; Chubinskaya, S; Willey, J S; Yammani, R R

2017-09-01

Insulin-like growth factor-1 (IGF-1) promotes matrix synthesis and cell survival in cartilage. Chondrocytes from aged and osteoarthritic cartilage have a reduced response to IGF-1. The purpose of this study was to determine the effect of free fatty acids (FFA) present in a high-fat diet on IGF-1 function in cartilage and the role of endoplasmic reticulum (ER) stress. C57BL/6 male mice were maintained on either a high-fat (60% kcal from fat) or a low-fat (10% kcal from fat) diet for 4 months. Mice were then sacrificed; femoral head cartilage caps were collected and treated with IGF-1 to measure proteoglycan (PG) synthesis. Cultured human chondrocytes were treated with 500 μM FFA palmitate or oleate, followed by stimulation with (100 ng/ml) IGF-1 overnight to measure CHOP (a protein marker for ER stress) and PG synthesis. Human chondrocytes were pre-treated with palmitate or 1 mM 4-phenyl butyric acid (PBA) or 1 μM C-Jun N terminal Kinase (JNK) inhibitor, and IGF-1 function (PG synthesis and signaling) was measured. Cartilage explants from mice on the high fat-diet showed reduced IGF-1 mediated PG synthesis compared to a low-fat group. Treatment of human chondrocytes with palmitate induced expression of CHOP, activated JNK and inhibited IGF-1 function. PBA, a small molecule chemical chaperone that alleviates ER stress rescued IGF-1 function and a JNK inhibitor rescued IGF-1 signaling. Palmitate-induced ER stress inhibited IGF-1 function in chondrocytes/cartilage via activating the mitogen-activated protein (MAP) kinase JNK. This is the first study to demonstrate that ER stress is metabolic factor that regulates IGF-1 function in chondrocytes. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

PPAR-δ Agonist With Mesenchymal Stem Cells Induces Type II Collagen-Producing Chondrocytes in Human Arthritic Synovial Fluid.

Science.gov (United States)

Heck, Bruce E; Park, Joshua J; Makani, Vishruti; Kim, Eun-Cheol; Kim, Dong Hyun

2017-08-01

Osteoarthritis (OA) is an inflammatory joint disease characterized by degeneration of articular cartilage within synovial joints. An estimated 27 million Americans suffer from OA, and the population is expected to reach 67 million in the United States by 2030. Thus, it is urgent to find an effective treatment for OA. Traditional OA treatments have no disease-modifying effect, while regenerative OA therapies such as autologous chondrocyte implantation show some promise. Nonetheless, current regenerative therapies do not overcome synovial inflammation that suppresses the differentiation of mesenchymal stem cells (MSCs) to chondrocytes and the expression of type II collagen, the major constituent of functional cartilage. We discovered a synergistic combination that overcame synovial inflammation to form type II collagen-producing chondrocytes. The combination consists of peroxisome proliferator-activated receptor (PPAR) δ agonist, human bone marrow (hBM)-derived MSCs, and hyaluronic acid (HA) gel. Interestingly, those individual components showed their own strong enhancing effects on chondrogenesis. GW0742, a PPAR-δ agonist, greatly enhanced MSC chondrogenesis and the expression of type II collagen and glycosaminoglycan (GAG) in hBM-MSC-derived chondrocytes. GW0742 also increased the expression of transforming growth factor β that enhances chondrogenesis and suppresses cartilage fibrillation, ossification, and inflammation. HA gel also increased MSC chondrogenesis and GAG production. However, neither GW0742 nor HA gel could enhance the formation of type II collagen-producing chondrocytes from hBM-MSCs within human OA synovial fluid. Our data demonstrated that the combination of hBM-MSCs, PPAR-δ agonist, and HA gel significantly enhanced the formation of type II collagen-producing chondrocytes within OA synovial fluid from 3 different donors. In other words, the novel combination of PPAR-δ agonist, hBM-MSCs, and HA gel can overcome synovial inflammation to form

Activation of Indian Hedgehog Promotes Chondrocyte Hypertrophy and Upregulation of MMP-13 in Human Osteoarthritic Cartilage

Science.gov (United States)

Wei, Fangyuan; Zhou, Jingming; Wei, Xiaochun; Zhang, Juntao; Fleming, Braden C.; Terek, Richard; Pei, Ming; Chen, Qian; Liu, Tao; Wei, Lei

2012-01-01

Objective The objectives of this study were to 1) determine the correlation between osteoarthritis (OA) and Ihh expression, and 2) establish the effects of Ihh on expression of markers of chondrocyte hypertrophy and MMP-13 in human OA cartilage. Design OA cartilage and synovial fluid samples were obtained during total knee arthroplasty. Normal cartilage samples were obtained from intra-articular tumor resections, and normal synovial fluid samples were obtained from healthy volunteers and the contralateral uninjured knee of patients undergoing anterior cruciate ligament reconstruction. OA was graded using the Mankin score. Expression of Ihh in synovial fluid was determined by western blot. Ihh, type X collagen and MMP-13 mRNA were determined by real time PCR. Protein expression of type X collagen and MMP-13 in cartilage samples were analyzed with immunohistochemistry. Chondrocyte size was measured using image analysis. Results Ihh expression was increased 2.6 fold in OA cartilage and 37% in OA synovial fluid when compared to normal control samples. Increased expression of Ihh was associated with the severity of OA and expression of markers of chondrocyte hypertrophy: type X collagen and MMP-13, and chondocyte size. Chondrocytes were more spherical with increasing severity of OA. There was a significant correlation between Mankin score and cell size (r2= 0.80) and Ihh intensity (r2 = 0.89). Exogenous Ihh induced a 6.8 fold increase of type X collagen and 2.8 fold increase of MMP-13 mRNA expression in cultured chondrocytes. Conversely, knockdown of Ihh by siRNA and Hh inhibitor Cyclopamine had the opposite effect. Conclusions Ihh expression correlates with OA progression and changes in chondrocyte morphology and gene expression consistent with chondrocyte hypertrophy and cartilage degradation seen in OA cartilage. Thus, Ihh may be a potential therapeutic target to prevent OA progression. PMID:22469853

Effects of scaffold composition and architecture on human nasal chondrocyte redifferentiation and cartilaginous matrix deposition

NARCIS (Netherlands)

Miot, Sylvie; Woodfield, T.B.F.; Daniels, Alma U.; Suetterlin, Rosemarie; Peterschmitt, Iman; Heberer, Michael; van Blitterswijk, Clemens; Riesle, J.U.; Martin, Ivan

2005-01-01

We investigated whether the post-expansion redifferentiation and cartilage tissue formation capacity of adult human nasal chondrocytes can be regulated by controlled modifications of scaffold composition and architecture. As a model system, we used poly(ethylene

Regulation of human mesenchymal stem cells differentiation into chondrocytes in extracellular matrix-based hydrogel scaffolds.

Science.gov (United States)

Du, Mingchun; Liang, Hui; Mou, Chenchen; Li, Xiaoran; Sun, Jie; Zhuang, Yan; Xiao, Zhifeng; Chen, Bing; Dai, Jianwu

2014-02-01

To induce human mesenchymal stem cells (hMSCs) to differentiate into chondrocytes in three-dimensional (3D) microenvironments, we developed porous hydrogel scaffolds using the cartilage extracellular matrix (ECM) components of chondroitin sulfate (CS) and collagen (COL). The turbidity and viscosity experiments indicated hydrogel could form through pH-triggered co-precipitation when pH=2-3. Enzyme-linked immunosorbent assay (ELISA) confirmed the hydrogel scaffolds could controllably release growth factors as envisaged. Transforming growth factor-β (TGF-β) was released to stimulate hMSCs differentiation into chondrocytes; and then collagen binding domain-basic fibroblast growth factor (CBD-bFGF) was released to improve the differentiation and preserve the chondrocyte phenotype. In in vitro cell culture experiments, the differentiation processes were compared in different microenvironments: 2D culture in culture plate as control, 3D culture in the fabricated scaffolds without growth factors (CC), the samples with CBD-bFGF (CC-C), the samples with TGF-β (CC-T), the samples with CBD-bFGF/TGF-β (CC-CT). Real-time polymerase chain reaction (RT-PCR) revealed the hMSC marker genes of CD44 and CD105 decreased; at the same time the chondrocyte marker genes of collagen type II and aggrecan increased, especially in the CC-CT sample. Immunostaining results further confirmed the hMSC marker protein of CD 44 disappeared and the chondrocyte marker protein of collagen type II emerged over time in the CC-CT sample. These results imply the ECM-based hydrogel scaffolds with growth factors can supply suitable 3D cell niches for hMSCs differentiation into chondrocytes and the differentiation process can be regulated by the controllably released growth factors. Copyright © 2013 Elsevier B.V. All rights reserved.

Chondrocytes and stem cells in 3D-bioprinted structures create human cartilage in vivo

OpenAIRE

Apelgren, Peter; Amoroso, Matteo; Lindahl, Anders; Brantsing, Camilla; Rotter, Nicole; Gatenholm, Paul; Kölby, Lars

2017-01-01

Cartilage repair and replacement is a major challenge in plastic reconstructive surgery. The development of a process capable of creating a patient-specific cartilage framework would be a major breakthrough. Here, we described methods for creating human cartilage in vivo and quantitatively assessing the proliferative capacity and cartilage-formation ability in mono- and co-cultures of human chondrocytes and human mesenchymal stem cells in a three-dimensional (3D)-bioprinted hydrogel scaffold....

Fetal Mesenchymal Stromal Cells Differentiating towards Chondrocytes Acquire a Gene Expression Profile Resembling Human Growth Plate Cartilage

NARCIS (Netherlands)

van Gool, S.A.; Emons, J.A.M.; Leijten, Jeroen Christianus Hermanus; Decker, E.; Sticht, C.; van Houwelingen, J.C.; Goeman, J.J.; Kleijburg, C.; Scherjon, S.; Gretz, N.; Wit, J.M.; Rappold, G.; Post, Janine Nicole; Karperien, Hermanus Bernardus Johannes

2012-01-01

Abstract We used human fetal bone marrow-derived mesenchymal stromal cells (hfMSCs) differentiating towards chondrocytes as an alternative model for the human growth plate (GP). Our aims were to study gene expression patterns associated with chondrogenic differentiation to assess whether

Role of interleukin-1 in antigen presentation by normal articular chondrocytes

International Nuclear Information System (INIS)

Tiku, M.L.; Liu, S.; Tiku, K.

1986-01-01

Recently the authors have described that normal articular chondrocytes of rabbits present antigen to immune T cells. In the present study the authors investigated the role of interleukin-1 (IL-1) on antigen presentation by chondrocytes. For these experiments the antigen pulsed chondroyctes were either untreated or fixed with paraformaldehyde and then co-cultured with immune T cells. T cell proliferation was measured by 3 H-thymidine incorporation. Pulsed non-fixed chondrocytes presented antigen, as expected, but pulsed and fixed cells failed to present antigen to T cells. The 3 H-TdR incorporation was partially restored by addition of purified human IL-1. Next, IL-1 activity was measured in primary chondrocyte culture supernatants stimulated with or without lipopolysaccharide (LPS) in comitogen thymocyte assay. No activity was detected in chondrocyte supernatants. Propagated chondrocyte culture supernatants also lacked IL-1 activity when stimulated with LPS in the presence of increasing concentration of indomethacin. On the other hand the authors observed that chondrocyte culture supernatants in a dose dependent manner inhibited human IL-1 induced 3 H-TdR incorporation of murine thymocytes. This suggested that these cells may produce an inhibitor of IL-1 and IL-1 production by chondrocytes may be essential for T cell proliferation by these cells. Inability to detect IL-1 in chondrocyte supernatants may be due to the presence of an inhibitor to IL-1. These findings may help in elucidating the immunological mechanisms in situations where chondrocytes and T cell interact, such as in arthritis

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Contribute to Chondrogenesis in Coculture with Chondrocytes.

Science.gov (United States)

Li, Xingfu; Duan, Li; Liang, Yujie; Zhu, Weimin; Xiong, Jianyi; Wang, Daping

2016-01-01

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs) and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation as well as to determine the optimal ratio of the two cell types. Also, we compared the difference between direct coculture and indirect coculture at low density. Monolayer cultures of hUCB-MSCs and hACs were investigated at different ratios, at direct cell-cell contact groups for 21 days. Compared to direct coculture, hUCB-MSCs and hACs indirect contact culture significantly increased type II collagen (COL2) and decreased type I collagen (COL1) protein expression levels. SRY-box 9 (SOX9) mRNA levels and protein expression were highest in indirect coculture. Overall, these results indicate that low density direct coculture induces fibrocartilage. However, indirect coculture in conditioned chondrocyte cell culture medium can increase expression of chondrogenic markers and induce hUCB-MSCs differentiation into mature chondrocytes. This work demonstrates that it is possible to promote chondrogenesis of hUCB-MSCs in combination with hACs, further supporting the concept of novel coculture strategies for tissue engineering.

Chondrocyte heterogeneity: immunohistologically defined variation of integrin expression at different sites in human fetal knees.

Science.gov (United States)

Salter, D M; Godolphin, J L; Gourlay, M S

1995-04-01

During development and at maturity different forms of cartilage vary in morphology and macromolecular content. This reflects heterogeneity of chondrocyte activity, in part involving differential interactions with the adjacent extracellular matrix via specialized cell surface receptors such as integrins. We undertook an immunohistological study on a series of human fetal knee joints to assess variation in the expression of integrins by chondrocytes and potential matrix ligands in articular, epiphyseal, growth plate, and meniscal cartilage. The results show that articular chondrocytes (beta 1+, beta 5 alpha V+, alpha 1+, alpha 2+/-, alpha 5+, weakly alpha 6+, alpha V+) differed from epiphyseal (beta 1+, beta 5 alpha V+, alpha 1+/-, alpha 2+/-, alpha 5+, alpha 6+, alpha V+) growth plate (beta 1+, beta 5 alpha V+, alpha 1-, alpha 2-, alpha 5+, alpha 6+, alpha V+), and meniscal cells (beta 1+, beta 5 alpha V+, alpha 1+, strongly alpha 2+, alpha 5+, alpha 6+, alpha V+ in expression of integrin subunits. There was no expression of beta 3, beta 4, beta 6, or alpha 3 by chondrocytes. These results differ from previous reports on the expression of integrins by adult articular cartilage, where alpha 2 and alpha 6 are not seen. Variation in distribution of matrix ligands was also seen. Fibronectin, laminin and Type VI collagen were expressed in all cartilages but there was restricted expression of tenascin, ED-A and ED-B fibronectin isoforms (articular cartilage and meniscus), and vitronectin (absent from growth plate cartilage). Regulated expression of integrins by chondrocytes, associated with changes in the pericellular matrix composition, is of potential importance in control of cartilage differentiation and function in health and disease.

Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

International Nuclear Information System (INIS)

Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon

2014-01-01

Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA

Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon, E-mail: yonseranglab@daum.net

2014-05-16

Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA.

Effect of Cell Sheet Manipulation Techniques on the Expression of Collagen Type II and Stress Fiber Formation in Human Chondrocyte Sheets.

Science.gov (United States)

Wongin, Sopita; Waikakul, Saranatra; Chotiyarnwong, Pojchong; Siriwatwechakul, Wanwipa; Viravaidya-Pasuwat, Kwanchanok

2018-03-01

Cell sheet technology is applied to human articular chondrocytes to construct a tissue-like structure as an alternative treatment for cartilage defect. The effect of a gelatin manipulator, as a cell sheet transfer system, on the quality of the chondrocyte sheets was investigated. The changes of important chondrogenic markers and stress fibers, resulting from the cell sheet manipulation, were also studied. The chondrocyte cell sheets were constructed with patient-derived chondrocytes using a temperature-responsive polymer and a gelatin manipulator as a transfer carrier. The properties of the cell sheets, including sizes, expression levels of collagen type II and I, and the localization of the stress fibers, were assessed and compared with those of the cell sheets harvested without the gelatin manipulator. Using the gelatin manipulator, the original size of the chondrocyte cell sheets was retained with abundant stress fibers, but with a decrease in the expression of collagen type II. Without the gelatin manipulator, although the cell shrinkage occurred, the cell sheet with suppressed stress fiber formation showed significantly higher levels of collagen type II. These results support our observations that stress fiber formation in chondrocyte cell sheets affected the production of chondrogenic markers. These densely packed tissue-like structures possessed a good chondrogenic activity, indicating their potential for use in autologous chondrocyte implantation to treat cartilage defects.

Antioxidant effect of bisphosphonates and simvastatin on chondrocyte lipid peroxidation

International Nuclear Information System (INIS)

Dombrecht, E.J.; De Tollenaere, C.B.; Aerts, K.; Cos, P.; Schuerwegh, A.J.; Bridts, C.H.; Van Offel, J.F.; Ebo, D.G.; Stevens, W.J.; De Clerck, L.S.

2006-01-01

The objective of this study was to evaluate the effect of bisphosphonates (BPs) and simvastatin on chondrocyte lipid peroxidation. For this purpose, a flow cytometrical method using C11-BODIPY 581/591 was developed to detect hydroperoxide-induced lipid peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP) induced a time and concentration dependent increase in chondrocyte lipid peroxidation. Addition of a Fe 2+ /EDTA complex to t-BHP or hydrogen peroxide (H 2 O 2 ) clearly enhanced lipid peroxidation. The lipophilic simvastatin demonstrated a small inhibition in the chondrocyte lipid peroxidation. None of three tested BPs (clodronate, pamidronate, and risedronate) had an effect on chondrocyte lipid peroxidation induced by t-BHP. However, when Fe 2+ /EDTA complex was added to t-BHP or H 2 O 2 , BPs inhibited the lipid peroxidation process varying from 25% to 58%. This study demonstrates that BPs have antioxidant properties as iron chelators, thereby inhibiting the chondrocyte lipid peroxidation. These findings add evidence to the therapeutic potential of bisphosphonates and statins in rheumatoid arthritis

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Contribute to Chondrogenesis in Coculture with Chondrocytes

Directory of Open Access Journals (Sweden)

Xingfu Li

2016-01-01

Full Text Available Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation as well as to determine the optimal ratio of the two cell types. Also, we compared the difference between direct coculture and indirect coculture at low density. Monolayer cultures of hUCB-MSCs and hACs were investigated at different ratios, at direct cell-cell contact groups for 21 days. Compared to direct coculture, hUCB-MSCs and hACs indirect contact culture significantly increased type II collagen (COL2 and decreased type I collagen (COL1 protein expression levels. SRY-box 9 (SOX9 mRNA levels and protein expression were highest in indirect coculture. Overall, these results indicate that low density direct coculture induces fibrocartilage. However, indirect coculture in conditioned chondrocyte cell culture medium can increase expression of chondrogenic markers and induce hUCB-MSCs differentiation into mature chondrocytes. This work demonstrates that it is possible to promote chondrogenesis of hUCB-MSCs in combination with hACs, further supporting the concept of novel coculture strategies for tissue engineering.

Considerations on the use of ear chondrocytes as donor chondrocytes for cartilage tissue engineering

NARCIS (Netherlands)

van Osch, Gerjo J. V. M.; Mandl, Erik W.; Jahr, Holger; Koevoet, Wendy; Nolst-Trenité, Gilbert; Verhaar, Jan A. N.

2004-01-01

Articular cartilage is often used for research on cartilage tissue engineering. However, ear cartilage is easier to harvest, with less donor-site morbidity. The aim of this study was to evaluate whether adult human ear chondrocytes were capable of producing cartilage after expansion in monolayer

R-spondin 2 facilitates differentiation of proliferating chondrocytes into hypertrophic chondrocytes by enhancing Wnt/β-catenin signaling in endochondral ossification

International Nuclear Information System (INIS)

Takegami, Yasuhiko; Ohkawara, Bisei; Ito, Mikako; Masuda, Akio; Nakashima, Hiroaki; Ishiguro, Naoki; Ohno, Kinji

2016-01-01

Endochondral ossification is a crucial process for longitudinal growth of bones. Differentiating chondrocytes in growth cartilage form four sequential zones of proliferation, alignment into column, hypertrophy, and substitution of chondrocytes with osteoblasts. Wnt/β-catenin signaling is essential for differentiation of proliferating chondrocytes into hypertrophic chondrocytes in growth cartilage. R-spondin 2 (Rspo2), a member of R-spondin family, is an agonist for Wnt signaling, but its role in chondrocyte differentiation remains unknown. Here we report that growth cartilage of Rspo2-knockout mice shows a decreased amount of β-catenin and increased amounts collagen type II (CII) and Sox9 in the abnormally extended proliferating zone. In contrast, expression of collagen type X (CX) in the hypertrophic zone remains unchanged. Differentiating chondrogenic ATDC5 cells, mimicking proliferating chondrocytes, upregulate Rspo2 and its putative receptor, Lgr5, in parallel. Addition of recombinant human Rspo2 to differentiating ATDC5 cells decreases expressions of Col2a1, Sox9, and Acan, as well as production of proteoglycans. In contrast, lentivirus-mediated knockdown of Rspo2 has the opposite effect. The effect of Rspo2 on chondrogenic differentiation is mediated by Wnt/β-catenin signaling, and not by Wnt/PCP or Wnt/Ca 2+ signaling. We propose that Rspo2 activates Wnt/β-catenin signaling to reduce Col2a1 and Sox9 and to facilitate differentiation of proliferating chondrocytes into hypertrophic chondrocytes in growth cartilage. - Highlights: • Rspo2 is a secreted activator of Wnt, and its knockout shows extended proliferating chondrocytes in endochondral ossification. • In proliferating chondrocytes of Rspo2-knockout mice, Sox9 and collagen type 2 are increased and β-catenin is decreased. • Rspo2 and its receptor Lgr5, as well as Sox9 and collagen type 2, are expressed in differentiating ATDC5 chondrogenic cells. • In ATDC5 cells, Rspo2 decreases expressions

R-spondin 2 facilitates differentiation of proliferating chondrocytes into hypertrophic chondrocytes by enhancing Wnt/β-catenin signaling in endochondral ossification

Energy Technology Data Exchange (ETDEWEB)

Takegami, Yasuhiko [Division of Neurogenetics, Center of Neurological Disease and Cancer, Nagoya University Graduate School of Medicine, Nagoya (Japan); Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya (Japan); Ohkawara, Bisei; Ito, Mikako; Masuda, Akio [Division of Neurogenetics, Center of Neurological Disease and Cancer, Nagoya University Graduate School of Medicine, Nagoya (Japan); Nakashima, Hiroaki; Ishiguro, Naoki [Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya (Japan); Ohno, Kinji, E-mail: ohnok@med.nagoya-u.ac.jp [Division of Neurogenetics, Center of Neurological Disease and Cancer, Nagoya University Graduate School of Medicine, Nagoya (Japan)

2016-04-22

Endochondral ossification is a crucial process for longitudinal growth of bones. Differentiating chondrocytes in growth cartilage form four sequential zones of proliferation, alignment into column, hypertrophy, and substitution of chondrocytes with osteoblasts. Wnt/β-catenin signaling is essential for differentiation of proliferating chondrocytes into hypertrophic chondrocytes in growth cartilage. R-spondin 2 (Rspo2), a member of R-spondin family, is an agonist for Wnt signaling, but its role in chondrocyte differentiation remains unknown. Here we report that growth cartilage of Rspo2-knockout mice shows a decreased amount of β-catenin and increased amounts collagen type II (CII) and Sox9 in the abnormally extended proliferating zone. In contrast, expression of collagen type X (CX) in the hypertrophic zone remains unchanged. Differentiating chondrogenic ATDC5 cells, mimicking proliferating chondrocytes, upregulate Rspo2 and its putative receptor, Lgr5, in parallel. Addition of recombinant human Rspo2 to differentiating ATDC5 cells decreases expressions of Col2a1, Sox9, and Acan, as well as production of proteoglycans. In contrast, lentivirus-mediated knockdown of Rspo2 has the opposite effect. The effect of Rspo2 on chondrogenic differentiation is mediated by Wnt/β-catenin signaling, and not by Wnt/PCP or Wnt/Ca{sup 2+} signaling. We propose that Rspo2 activates Wnt/β-catenin signaling to reduce Col2a1 and Sox9 and to facilitate differentiation of proliferating chondrocytes into hypertrophic chondrocytes in growth cartilage. - Highlights: • Rspo2 is a secreted activator of Wnt, and its knockout shows extended proliferating chondrocytes in endochondral ossification. • In proliferating chondrocytes of Rspo2-knockout mice, Sox9 and collagen type 2 are increased and β-catenin is decreased. • Rspo2 and its receptor Lgr5, as well as Sox9 and collagen type 2, are expressed in differentiating ATDC5 chondrogenic cells. • In ATDC5 cells, Rspo2 decreases

Lithium Chloride Dependent Glycogen Synthase Kinase 3 Inactivation Links Oxidative DNA Damage, Hypertrophy and Senescence in Human Articular Chondrocytes and Reproduces Chondrocyte Phenotype of Obese Osteoarthritis Patients.

Directory of Open Access Journals (Sweden)

Serena Guidotti

Full Text Available Recent evidence suggests that GSK3 activity is chondroprotective in osteoarthritis (OA, but at the same time, its inactivation has been proposed as an anti-inflammatory therapeutic option. Here we evaluated the extent of GSK3β inactivation in vivo in OA knee cartilage and the molecular events downstream GSK3β inactivation in vitro to assess their contribution to cell senescence and hypertrophy.In vivo level of phosphorylated GSK3β was analyzed in cartilage and oxidative damage was assessed by 8-oxo-deoxyguanosine staining. The in vitro effects of GSK3β inactivation (using either LiCl or SB216763 were evaluated on proliferating primary human chondrocytes by combined confocal microscopy analysis of Mitotracker staining and reactive oxygen species (ROS production (2',7'-dichlorofluorescin diacetate staining. Downstream effects on DNA damage and senescence were investigated by western blot (γH2AX, GADD45β and p21, flow cytometric analysis of cell cycle and light scattering properties, quantitative assessment of senescence associated β galactosidase activity, and PAS staining.In vivo chondrocytes from obese OA patients showed higher levels of phosphorylated GSK3β, oxidative damage and expression of GADD45β and p21, in comparison with chondrocytes of nonobese OA patients. LiCl mediated GSK3β inactivation in vitro resulted in increased mitochondrial ROS production, responsible for reduced cell proliferation, S phase transient arrest, and increase in cell senescence, size and granularity. Collectively, western blot data supported the occurrence of a DNA damage response leading to cellular senescence with increase in γH2AX, GADD45β and p21. Moreover, LiCl boosted 8-oxo-dG staining, expression of IKKα and MMP-10.In articular chondrocytes, GSK3β activity is required for the maintenance of proliferative potential and phenotype. Conversely, GSK3β inactivation, although preserving chondrocyte survival, results in functional impairment via

Lithium Chloride Dependent Glycogen Synthase Kinase 3 Inactivation Links Oxidative DNA Damage, Hypertrophy and Senescence in Human Articular Chondrocytes and Reproduces Chondrocyte Phenotype of Obese Osteoarthritis Patients.

Science.gov (United States)

Guidotti, Serena; Minguzzi, Manuela; Platano, Daniela; Cattini, Luca; Trisolino, Giovanni; Mariani, Erminia; Borzì, Rosa Maria

2015-01-01

Recent evidence suggests that GSK3 activity is chondroprotective in osteoarthritis (OA), but at the same time, its inactivation has been proposed as an anti-inflammatory therapeutic option. Here we evaluated the extent of GSK3β inactivation in vivo in OA knee cartilage and the molecular events downstream GSK3β inactivation in vitro to assess their contribution to cell senescence and hypertrophy. In vivo level of phosphorylated GSK3β was analyzed in cartilage and oxidative damage was assessed by 8-oxo-deoxyguanosine staining. The in vitro effects of GSK3β inactivation (using either LiCl or SB216763) were evaluated on proliferating primary human chondrocytes by combined confocal microscopy analysis of Mitotracker staining and reactive oxygen species (ROS) production (2',7'-dichlorofluorescin diacetate staining). Downstream effects on DNA damage and senescence were investigated by western blot (γH2AX, GADD45β and p21), flow cytometric analysis of cell cycle and light scattering properties, quantitative assessment of senescence associated β galactosidase activity, and PAS staining. In vivo chondrocytes from obese OA patients showed higher levels of phosphorylated GSK3β, oxidative damage and expression of GADD45β and p21, in comparison with chondrocytes of nonobese OA patients. LiCl mediated GSK3β inactivation in vitro resulted in increased mitochondrial ROS production, responsible for reduced cell proliferation, S phase transient arrest, and increase in cell senescence, size and granularity. Collectively, western blot data supported the occurrence of a DNA damage response leading to cellular senescence with increase in γH2AX, GADD45β and p21. Moreover, LiCl boosted 8-oxo-dG staining, expression of IKKα and MMP-10. In articular chondrocytes, GSK3β activity is required for the maintenance of proliferative potential and phenotype. Conversely, GSK3β inactivation, although preserving chondrocyte survival, results in functional impairment via induction of

Green tea polyphenol epigallocatechin-3-gallate inhibits advanced glycation end product-induced expression of tumor necrosis factor-alpha and matrix metalloproteinase-13 in human chondrocytes.

Science.gov (United States)

Rasheed, Zafar; Anbazhagan, Arivarasu N; Akhtar, Nahid; Ramamurthy, Sangeetha; Voss, Frank R; Haqqi, Tariq M

2009-01-01

The major risk factor for osteoarthritis (OA) is aging, but the mechanisms underlying this risk are only partly understood. Age-related accumulation of advanced glycation end products (AGEs) can activate chondrocytes and induce the production of proinflammatory cytokines and matrix metalloproteinases (MMPs). In the present study, we examined the effect of epigallocatechin-3-gallate (EGCG) on AGE-modified-BSA (AGE-BSA)-induced activation and production of TNFalpha and MMP-13 in human OA chondrocytes. Human chondrocytes were derived from OA cartilage by enzymatic digestion and stimulated with in vitro-generated AGE-BSA. Gene expression of TNFalpha and MMP-13 was measured by quantitative RT-PCR. TNFalpha protein in culture medium was determined using cytokine-specific ELISA. Western immunoblotting was used to analyze the MMP-13 production in the culture medium, phosphorylation of mitogen-activated protein kinases (MAPKs), and the activation of NF-kappaB. DNA binding activity of NF-kappaB p65 was determined using a highly sensitive and specific ELISA. IkappaB kinase (IKK) activity was determined using an in vitro kinase activity assay. MMP-13 activity in the culture medium was assayed by gelatin zymography. EGCG significantly decreased AGE-stimulated gene expression and production of TNFalpha and MMP-13 in human chondrocytes. The inhibitory effect of EGCG on the AGE-BSA-induced expression of TNFalpha and MMP-13 was mediated at least in part via suppression of p38-MAPK and JNK activation. In addition, EGCG inhibited the phosphorylating activity of IKKbeta kinase in an in vitro activity assay and EGCG inhibited the AGE-mediated activation and DNA binding activity of NF-kappaB by suppressing the degradation of its inhibitory protein IkappaBalpha in the cytoplasm. These novel pharmacological actions of EGCG on AGE-BSA-stimulated human OA chondrocytes provide new suggestions that EGCG or EGCG-derived compounds may inhibit cartilage degradation by suppressing AGE

Fetal mesenchymal stromal cells differentiating towards chondrocytes acquire a gene expression profile resembling human growth plate cartilage.

Directory of Open Access Journals (Sweden)

Sandy A van Gool

Full Text Available We used human fetal bone marrow-derived mesenchymal stromal cells (hfMSCs differentiating towards chondrocytes as an alternative model for the human growth plate (GP. Our aims were to study gene expression patterns associated with chondrogenic differentiation to assess whether chondrocytes derived from hfMSCs are a suitable model for studying the development and maturation of the GP. hfMSCs efficiently formed hyaline cartilage in a pellet culture in the presence of TGFβ3 and BMP6. Microarray and principal component analysis were applied to study gene expression profiles during chondrogenic differentiation. A set of 232 genes was found to correlate with in vitro cartilage formation. Several identified genes are known to be involved in cartilage formation and validate the robustness of the differentiating hfMSC model. KEGG pathway analysis using the 232 genes revealed 9 significant signaling pathways correlated with cartilage formation. To determine the progression of growth plate cartilage formation, we compared the gene expression profile of differentiating hfMSCs with previously established expression profiles of epiphyseal GP cartilage. As differentiation towards chondrocytes proceeds, hfMSCs gradually obtain a gene expression profile resembling epiphyseal GP cartilage. We visualized the differences in gene expression profiles as protein interaction clusters and identified many protein clusters that are activated during the early chondrogenic differentiation of hfMSCs showing the potential of this system to study GP development.

RHEB: a potential regulator of chondrocyte phenotype for cartilage tissue regeneration.

Science.gov (United States)

Ashraf, S; Ahn, J; Cha, B-H; Kim, J-S; Han, I; Park, H; Lee, S-H

2017-09-01

As articular cartilage has a limited ability to self-repair, successful cartilage regeneration requires clinical-grade chondrocytes with innate characteristics. However, cartilage regeneration via chondrocyte transplantation is challenging, because chondrocytes lose their innate characteristics during in vitro expansion. Here, we investigated the mechanistic underpinning of the gene Ras homologue enriched in brain (RHEB) in the control of senescence and dedifferentiation through the modulation of oxidative stress in chondrocytes, a hallmark of osteoarthritis. Serial expansion of human chondrocytes led to senescence, dedifferentiation and oxidative stress. RHEB maintained the innate characteristics of chondrocytes by regulating senescence, dedifferentiation and oxidative stress, leading to the upregulation of COL2 expression via SOX9 and the downregulation of p27 expression via MCL1. RHEB also decreased the expression of COL10. RHEB knockdown mimics decreased the expression of SOX9, COL2 and MCL1, while abrogating the suppressive function of RHEB on p27 and COL10 in chondrocytes. RHEB-overexpressing chondrocytes successfully formed cartilage tissue in vitro as well as in vivo, with increased expression of GAG matrix and chondrogenic markers. RHEB induces a distinct gene expression signature that maintained the innate chondrogenic properties over a long period. Therefore, RHEB expression represents a potentially useful mechanism in terms of cartilage tissue regeneration from chondrocytes, by which chondrocyte phenotypic and molecular characteristics can be retained through the modulation of senescence, dedifferentiation and oxidative stress. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Effect of donor age on DNA repair by articular chondrocytes

International Nuclear Information System (INIS)

Lipman, J.M.

1986-01-01

The hypothesis that aging of articular chondrocytes at a cellular level results from loss of DNA repair capability was studied by two different measures: unscheduled DNA synthesis (UDS) and O 6 -methylguanine acceptor protein (MGAP) activity. UDS following damage by 254 nm ultraviolet irradiation (20J/m 2 ) was examined in intact articular cartilage from rabbits of different ages. Semiconservative DNA synthesis was suppressed with hydroxurea and repair followed by the incorporation of [ 3 H]-thymidine ([ 3 H]-dThd). After repair the cartilage was digested in proteinase K (0.5mg/ml) with dodecyl sodium sulfate (0.2%) and DNA determined with Hoechst 33258 dye. UDS (dpm [ 3 H]-dThd/μg DNA) was greater in articular cartilage from 3- than 39-month-old rabbits. MGAP was studied in cell extracts of cultured human and rabbit chondrocytes by transfer of [ 3 H] O 6 -methyl groups from exogenous DNA to protein. It was significantly less in rabbit than in human cells on a per protein or DNA basis. There was no decline in this activity in human chondrocytes from newborn to 60 years of age; and rabbits from 3- to 36-months-old. The data indicate that in the two different repair mechanisms, age differences are found with resting but not dividing chondrocytes

Chondrocyte-seeded type I/III collagen membrane for autologous chondrocyte transplantation

DEFF Research Database (Denmark)

Niemeyer, Philipp; Lenz, Philipp; Kreuz, Peter C

2010-01-01

PURPOSE: We report the 2-year clinical results and identify prognostic factors in patients treated with autologous chondrocyte transplantation by use of a collagen membrane to seed the chondrocytes (ACT-CS). METHODS: This is a prospective study of 59 patients who were treated with ACT......-CS represents a technical modification of membrane-associated autologous chondrocyte transplantation that combines easy handling and attractive application properties with reliable clinical results 24 months after surgery, especially in patients with isolated cartilage defects. Even though the failure rate...

SHP2 regulates chondrocyte terminal differentiation, growth plate architecture and skeletal cell fates.

Directory of Open Access Journals (Sweden)

Margot E Bowen

Full Text Available Loss of PTPN11/SHP2 in mice or in human metachondromatosis (MC patients causes benign cartilage tumors on the bone surface (exostoses and within bones (enchondromas. To elucidate the mechanisms underlying cartilage tumor formation, we investigated the role of SHP2 in the specification, maturation and organization of chondrocytes. Firstly, we studied chondrocyte maturation by performing RNA-seq on primary chondrocyte pellet cultures. We found that SHP2 depletion, or inhibition of the ERK1/2 pathway, delays the terminal differentiation of chondrocytes from the early-hypertrophic to the late-hypertrophic stage. Secondly, we studied chondrocyte maturation and organization in mice with a mosaic postnatal inactivation of Ptpn11 in chondrocytes. We found that the vertebral growth plates of these mice have expanded domains of early-hypertrophic chondrocytes that have not yet terminally differentiated, and their enchondroma-like lesions arise from chondrocytes displaced from the growth plate due to a disruption in the organization of maturation and ossification zones. Furthermore, we observed that lesions from human MC patients also display disorganized chondrocyte maturation zones. Next, we found that inactivation of Ptpn11 in Fsp1-Cre-expressing fibroblasts induces exostosis-like outgrowths, suggesting that loss of SHP2 in cells on the bone surface and at bone-ligament attachment sites induces ectopic chondrogenesis. Finally, we performed lineage tracing to show that exostoses and enchondromas in mice likely contain mixtures of wild-type and SHP2-deficient chondrocytes. Together, these data indicate that in patients with MC, who are heterozygous for inherited PTPN11 loss-of-function mutations, second-hit mutations in PTPN11 can induce enchondromas by disrupting the organization and delaying the terminal differentiation of growth plate chondrocytes, and can induce exostoses by causing ectopic chondrogenesis of cells on the bone surface. Furthermore, the

[Comparative effects of vitamin C on the effects of local anesthetics ropivacaine, bupivacaine, and lidocaine on human chondrocytes].

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Tian, Jun; Li, Yan

2016-01-01

Intra-articular injections of local anesthetics are commonly used to enhance post-operative analgesia following orthopedic surgery as arthroscopic surgeries. Nevertheless, recent reports of severe complications due to the use of intra-articular local anesthetic have raised concerns. The study aims to assess use of vitamin C in reducing adverse effects of the most commonly employed anesthetics - ropivacaine, bupivacaine and lidocaine - on human chondrocytes. The chondrocyte viability following exposure to 0.5% bupivacaine or 0.75% ropivacaine or 1.0% lidocaine and/or vitamin C at doses 125, 250 and 500μM was determined by Live/Dead assay and annexin V staining. Expression levels of caspases 3 and 9 were assessed using antibodies by Western blotting. Flow cytometry was performed to analyze the generation of reactive oxygen species. On exposure to the local anesthetics, chondrotoxicity was found in the order ropivacaineC effectively improved the reduced chondrocyte viability and decreased the raised apoptosis levels following exposure to anesthesia. At higher doses, vitamin C was found efficient in reducing the generation of reactive oxygen species and as well down-regulate the expressions of caspases 3 and 9. Vitamin C was observed to effectively protect chondrocytes against the toxic insult of local anesthetics ropivacaine, bupivacaine and lidocaine. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Comparative effects of vitamin C on the effects of local anesthetics ropivacaine, bupivacaine, and lidocaine on human chondrocytes.

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Tian, Jun; Li, Yan

2016-01-01

Intra-articular injections of local anesthetics are commonly used to enhance post-operative analgesia following orthopedic surgery as arthroscopic surgeries. Nevertheless, recent reports of severe complications due to the use of intra-articular local anesthetic have raised concerns. The study aims to assess use of vitamin C in reducing adverse effects of the most commonly employed anesthetics - ropivacaine, bupivacaine and lidocaine - on human chondrocytes. The chondrocyte viability following exposure to 0.5% bupivacaine or 0.75% ropivacaine or 1.0% lidocaine and/or vitamin C at doses 125, 250 and 500 μM was determined by LIVE/DEAD assay and annexin V staining. Expression levels of caspases 3 and 9 were assessed using antibodies by Western blotting. Flow cytometry was performed to analyze the generation of reactive oxygen species. On exposure to the local anesthetics, chondrotoxicity was found in the order ropivacaineC effectively improved the reduced chondrocyte viability and decreased the raised apoptosis levels following exposure to anesthesia. At higher doses, vitamin C was found efficient in reducing the generation of reactive oxygen species and as well down-regulate the expressions of caspases 3 and 9. Vitamin C was observed to effectively protect chondrocytes against the toxic insult of local anesthetics ropivacaine, bupivacaine and lidocaine. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Inflammation induction of Dickkopf-1 mediates chondrocyte apoptosis in osteoarthritic joint.

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Weng, L-H; Wang, C-J; Ko, J-Y; Sun, Y-C; Su, Y-S; Wang, F-S

2009-07-01

Dysregulated Wnt signaling appears to modulate chondrocyte fate and joint disorders. Dickkopf-1 (DKK1) regulates the pathogenesis of skeletal tissue by inhibiting Wnt actions. This study examined whether DKK1 expression is linked to chondrocyte fate in osteoarthritis (OA). Articular cartilage specimens harvested from nine patients with knee OA and from six controls with femoral neck fracture were assessed for DKK1, interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), Bad, Bax, Bcl2 and caspase-3 expression by real time-polymerase chain reaction (RT-PCR) and immunohistochemistry. Apoptotic chondrocytes were detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labelling (TUNEL) and 4', 6-dianidino-2-phenylindole dihydrochloride (DAPI) staining. Human chondrocyte cultures were treated with recombinant IL-1beta and monoclonal DKK1 antibody to determine whether DKK1 impairs chondrocyte survival. Expression of DKK1 correlated with inflammatory cytokine levels (IL-1beta and TNF-alpha expressions), proapoptosis regulators (Bad and caspase-3 expressions) and TUNEL staining in OA cartilage tissues. The IL-1beta induced expressions of DKK1, Bax, Bad and caspase-3-dependent apoptosis of chondrocyte cultures. Neutralization of DKK1 by monoclonal DKK1 antibody significantly abrogated IL-1beta-mediated caspase-3 cleavage and apoptosis and reversed chondrocyte proliferation. Recombinant DKK1 treatment impaired chondrocyte growth and promoted apoptosis. By suppressing nuclear beta-catenin accumulation and Akt phosphorylation, DKK1 mediated IL-1beta promotion of chondrocyte apoptosis. Chondrocyte apoptosis correlates with joint OA. Expression of DKK1 contributes to cartilage deterioration and is a potent factor in OA pathogenesis. Attenuating DKK1 may reduce cartilage deterioration in OA.

The effects of monosodium urate monohydrate crystals on chondrocyte viability and function: implications for development of cartilage damage in gout.

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Chhana, Ashika; Callon, Karen E; Pool, Bregina; Naot, Dorit; Gamble, Gregory D; Dray, Michael; Pitto, Rocco; Bentley, Jarome; McQueen, Fiona M; Cornish, Jillian; Dalbeth, Nicola

2013-12-01

Cartilage damage is frequently observed in advanced destructive gout. The aim of our study was to investigate the effects of monosodium urate monohydrate (MSU) crystals on chondrocyte viability and function. The alamarBlue assay and flow cytometry were used to assess the viability of primary human chondrocytes and cartilage explants following culture with MSU crystals. The number of dead chondrocytes in cartilage explants cultured with MSU crystals was quantified. Real-time PCR was used to determine changes in the relative mRNA expression levels of chondrocytic genes. The histological appearance of cartilage in joints affected by gout was also examined. MSU crystals rapidly reduced primary human chondrocyte and cartilage explant viability in a dose-dependent manner (p gout, normal cartilage architecture was lost, with empty chondrocyte lacunae observed. MSU crystals have profound inhibitory effects on chondrocyte viability and function. Interactions between MSU crystals and chondrocytes may contribute to cartilage damage in gout through reduction of chondrocyte viability and promotion of a catabolic state.

High throughput generated micro-aggregates of chondrocytes stimulate cartilage formation in vitro and in vivo

Directory of Open Access Journals (Sweden)

LS Moreira Teixeira

2012-06-01

Full Text Available Cell-based cartilage repair strategies such as matrix-induced autologous chondrocyte implantation (MACI could be improved by enhancing cell performance. We hypothesised that micro-aggregates of chondrocytes generated in high-throughput prior to implantation in a defect could stimulate cartilaginous matrix deposition and remodelling. To address this issue, we designed a micro-mould to enable controlled high-throughput formation of micro-aggregates. Morphology, stability, gene expression profiles and chondrogenic potential of micro-aggregates of human and bovine chondrocytes were evaluated and compared to single-cells cultured in micro-wells and in 3D after encapsulation in Dextran-Tyramine (Dex-TA hydrogels in vitro and in vivo. We successfully formed micro-aggregates of human and bovine chondrocytes with highly controlled size, stability and viability within 24 hours. Micro-aggregates of 100 cells presented a superior balance in Collagen type I and Collagen type II gene expression over single cells and micro-aggregates of 50 and 200 cells. Matrix metalloproteinases 1, 9 and 13 mRNA levels were decreased in micro-aggregates compared to single-cells. Histological and biochemical analysis demonstrated enhanced matrix deposition in constructs seeded with micro-aggregates cultured in vitro and in vivo, compared to single-cell seeded constructs. Whole genome microarray analysis and single gene expression profiles using human chondrocytes confirmed increased expression of cartilage-related genes when chondrocytes were cultured in micro-aggregates. In conclusion, we succeeded in controlled high-throughput formation of micro-aggregates of chondrocytes. Compared to single cell-seeded constructs, seeding of constructs with micro-aggregates greatly improved neo-cartilage formation. Therefore, micro-aggregation prior to chondrocyte implantation in current MACI procedures, may effectively accelerate hyaline cartilage formation.

High throughput generated micro-aggregates of chondrocytes stimulate cartilage formation in vitro and in vivo.

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Moreira Teixeira, L S; Leijten, J C H; Sobral, J; Jin, R; van Apeldoorn, A A; Feijen, J; van Blitterswijk, C; Dijkstra, P J; Karperien, M

2012-06-05

Cell-based cartilage repair strategies such as matrix-induced autologous chondrocyte implantation (MACI) could be improved by enhancing cell performance. We hypothesised that micro-aggregates of chondrocytes generated in high-throughput prior to implantation in a defect could stimulate cartilaginous matrix deposition and remodelling. To address this issue, we designed a micro-mould to enable controlled high-throughput formation of micro-aggregates. Morphology, stability, gene expression profiles and chondrogenic potential of micro-aggregates of human and bovine chondrocytes were evaluated and compared to single-cells cultured in micro-wells and in 3D after encapsulation in Dextran-Tyramine (Dex-TA) hydrogels in vitro and in vivo. We successfully formed micro-aggregates of human and bovine chondrocytes with highly controlled size, stability and viability within 24 hours. Micro-aggregates of 100 cells presented a superior balance in Collagen type I and Collagen type II gene expression over single cells and micro-aggregates of 50 and 200 cells. Matrix metalloproteinases 1, 9 and 13 mRNA levels were decreased in micro-aggregates compared to single-cells. Histological and biochemical analysis demonstrated enhanced matrix deposition in constructs seeded with micro-aggregates cultured in vitro and in vivo, compared to single-cell seeded constructs. Whole genome microarray analysis and single gene expression profiles using human chondrocytes confirmed increased expression of cartilage-related genes when chondrocytes were cultured in micro-aggregates. In conclusion, we succeeded in controlled high-throughput formation of micro-aggregates of chondrocytes. Compared to single cell-seeded constructs, seeding of constructs with micro-aggregates greatly improved neo-cartilage formation. Therefore, micro-aggregation prior to chondrocyte implantation in current MACI procedures, may effectively accelerate hyaline cartilage formation.

Rabbit chondrocytes maintained in serum-free medium. I. Synthesis and secretion of hydrodynamically-small proteoglycans

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Malemud, C.J.; Papay, R.S.

1986-01-01

The biosynthesis of sulfated proteoglycan in vitro by rabbit articular chondrocytes in first passage monolayer culture maintained in fetal bovine serum (FBS) or in serum-free conditions was compared. Neosynthesized proteoglycan in the culture medium in the most dense fraction of an associative CsCl density gradient (fraction dAl) declined with increasing time under serum-free conditions, but not when cells were maintained in the presence of serum. After one day, the major peak of incorporated 35 SO 4 in medium fraction dAl eluted as a retarded peak on Sepharose CL-2B, whether cells were maintained under serum-free or serum-containing conditions. The hydrodynamic size of proteoglycan monomer fraction dAlDl obtained after one day of exposure to serum-free culture media was smaller than dAlDl from serum-containing cultures. The hydrodynamic size of dAlDl obtained from serum-free culture media became even progressively smaller after 2 and 3 days' exposure to these conditions. Hydrodynamically small sulfated proteoglycans were identified in the cell-associated dAlDl fraction as early as one day after switching chondrocytes from serum-containing to serum-free medium. Proteoglycan monomer from serum-containing medium reaggregated more efficiently under both conditions. No change in the size of glycosaminoglycan chains was seen in the smaller proteoglycan subpopulations, nor was there any indication of marked changes in the glycosaminoglycan types

Nasal chondrocyte-based engineered autologous cartilage tissue for repair of articular cartilage defects: an observational first-in-human trial.

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Mumme, Marcus; Barbero, Andrea; Miot, Sylvie; Wixmerten, Anke; Feliciano, Sandra; Wolf, Francine; Asnaghi, Adelaide M; Baumhoer, Daniel; Bieri, Oliver; Kretzschmar, Martin; Pagenstert, Geert; Haug, Martin; Schaefer, Dirk J; Martin, Ivan; Jakob, Marcel

2016-10-22

Articular cartilage injuries have poor repair capacity, leading to progressive joint damage, and cannot be restored predictably by either conventional treatments or advanced therapies based on implantation of articular chondrocytes. Compared with articular chondrocytes, chondrocytes derived from the nasal septum have superior and more reproducible capacity to generate hyaline-like cartilage tissues, with the plasticity to adapt to a joint environment. We aimed to assess whether engineered autologous nasal chondrocyte-based cartilage grafts allow safe and functional restoration of knee cartilage defects. In a first-in-human trial, ten patients with symptomatic, post-traumatic, full-thickness cartilage lesions (2-6 cm 2 ) on the femoral condyle or trochlea were treated at University Hospital Basel in Switzerland. Chondrocytes isolated from a 6 mm nasal septum biopsy specimen were expanded and cultured onto collagen membranes to engineer cartilage grafts (30 × 40 × 2 mm). The engineered tissues were implanted into the femoral defects via mini-arthrotomy and assessed up to 24 months after surgery. Primary outcomes were feasibility and safety of the procedure. Secondary outcomes included self-assessed clinical scores and MRI-based estimation of morphological and compositional quality of the repair tissue. This study is registered with ClinicalTrials.gov, number NCT01605201. The study is ongoing, with an approved extension to 25 patients. For every patient, it was feasible to manufacture cartilaginous grafts with nasal chondrocytes embedded in an extracellular matrix rich in glycosaminoglycan and type II collagen. Engineered tissues were stable through handling with forceps and could be secured in the injured joints. No adverse reactions were recorded and self-assessed clinical scores for pain, knee function, and quality of life were improved significantly from before surgery to 24 months after surgery. Radiological assessments indicated variable degrees of

Molecular analysis of expansion, differentiation, and growth factor treatment of human chondrocytes identifies differentiation markers and growth-related genes.

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Benz, Karin; Breit, Stephen; Lukoschek, Martin; Mau, Hans; Richter, Wiltrud

2002-04-26

This study is intended to optimise expansion and differentiation of cultured human chondrocytes by growth factor application and to identify molecular markers to monitor their differentiation state. We dissected the molecular consequences of matrix release, monolayer, and 3D-alginate culture, growth factor optimised expansion, and re-differentiation protocols by gene expression analysis. Among 19 common cartilage molecules assessed by cDNA array, six proved best to monitor differentiation. Instant down-regulation at release of cells from the matrix was strongest for COL 2A1, fibromodulin, and PRELP while LUM, CHI3L1, and CHI3L2 were expansion-related. Both gene sets reflected the physiologic effects of the most potent growth-inducing (PDGF-BB) and proteoglycan-inducing (BMP-4) factors. Only CRTAC1 expression correlated with 2D/3D switches while the molecular phenotype of native chondrocytes was not restored. The markers and optimised protocols we suggest can help to improve cell therapy of cartilage defects and chondrocyte differentiation from stem cell sources.

Cartilage repair: Generations of autologous chondrocyte transplantation

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Marlovits, Stefan; Zeller, Philip; Singer, Philipp; Resinger, Christoph; Vecsei, Vilmos

2006-01-01

Articular cartilage in adults has a limited capacity for self-repair after a substantial injury. Surgical therapeutic efforts to treat cartilage defects have focused on delivering new cells capable of chondrogenesis into the lesions. Autologous chondrocyte transplantation (ACT) is an advanced cell-based orthobiologic technology used for the treatment of chondral defects of the knee that has been in clinical use since 1987 and has been performed on 12,000 patients internationally. With ACT, good to excellent clinical results are seen in isolated post-traumatic lesions of the knee joint in the younger patient, with the formation of hyaline or hyaline-like repair tissue. In the classic ACT technique, chondrocytes are isolated from small slices of cartilage harvested arthroscopically from a minor weight-bearing area of the injured knee. The extracellular matrix is removed by enzymatic digestion, and the cells are then expanded in monolayer culture. Once a sufficient number of cells has been obtained, the chondrocytes are implanted into the cartilage defect, using a periosteal patch over the defect as a method of cell containment. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. Further improvements in tissue engineering have contributed to the next generation of ACT techniques, where cells are combined with resorbable biomaterials, as in matrix-associated autologous chondrocyte transplantation (MACT). These biomaterials secure the cells in the defect area and enhance their proliferation and differentiation

Cartilage repair: Generations of autologous chondrocyte transplantation

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Marlovits, Stefan [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.marlovits@meduniwien.ac.at; Zeller, Philip [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Singer, Philipp [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Resinger, Christoph [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Vecsei, Vilmos [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

2006-01-15

Articular cartilage in adults has a limited capacity for self-repair after a substantial injury. Surgical therapeutic efforts to treat cartilage defects have focused on delivering new cells capable of chondrogenesis into the lesions. Autologous chondrocyte transplantation (ACT) is an advanced cell-based orthobiologic technology used for the treatment of chondral defects of the knee that has been in clinical use since 1987 and has been performed on 12,000 patients internationally. With ACT, good to excellent clinical results are seen in isolated post-traumatic lesions of the knee joint in the younger patient, with the formation of hyaline or hyaline-like repair tissue. In the classic ACT technique, chondrocytes are isolated from small slices of cartilage harvested arthroscopically from a minor weight-bearing area of the injured knee. The extracellular matrix is removed by enzymatic digestion, and the cells are then expanded in monolayer culture. Once a sufficient number of cells has been obtained, the chondrocytes are implanted into the cartilage defect, using a periosteal patch over the defect as a method of cell containment. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. Further improvements in tissue engineering have contributed to the next generation of ACT techniques, where cells are combined with resorbable biomaterials, as in matrix-associated autologous chondrocyte transplantation (MACT). These biomaterials secure the cells in the defect area and enhance their proliferation and differentiation.

Passaged adult chondrocytes can form engineered cartilage with functional mechanical properties: a canine model.

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Ng, Kenneth W; Lima, Eric G; Bian, Liming; O'Conor, Christopher J; Jayabalan, Prakash S; Stoker, Aaron M; Kuroki, Keiichi; Cook, Cristi R; Ateshian, Gerard A; Cook, James L; Hung, Clark T

2010-03-01

It was hypothesized that previously optimized serum-free culture conditions for juvenile bovine chondrocytes could be adapted to generate engineered cartilage with physiologic mechanical properties in a preclinical, adult canine model. Primary or passaged (using growth factors) adult chondrocytes from three adult dogs were encapsulated in agarose, and cultured in serum-free media with transforming growth factor-beta3. After 28 days in culture, engineered cartilage formed by primary chondrocytes exhibited only small increases in glycosaminoglycan content. However, all passaged chondrocytes on day 28 elaborated a cartilage matrix with compressive properties and glycosaminoglycan content in the range of native adult canine cartilage values. A preliminary biocompatibility study utilizing chondral and osteochondral constructs showed no gross or histological signs of rejection, with all implanted constructs showing excellent integration with surrounding cartilage and subchondral bone. This study demonstrates that adult canine chondrocytes can form a mechanically functional, biocompatible engineered cartilage tissue under optimized culture conditions. The encouraging findings of this work highlight the potential for tissue engineering strategies using adult chondrocytes in the clinical treatment of cartilage defects.

The chondrocytic journey in endochondral bone growth and skeletal dysplasia.

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Yeung Tsang, Kwok; Wa Tsang, Shun; Chan, Danny; Cheah, Kathryn S E

2014-03-01

The endochondral bones of the skeleton develop from a cartilage template and grow via a process involving a cascade of chondrocyte differentiation steps culminating in formation of a growth plate and the replacement of cartilage by bone. This process of endochondral ossification, driven by the generation of chondrocytes and their subsequent proliferation, differentiation, and production of extracellular matrix constitute a journey, deviation from which inevitably disrupts bone growth and development, and is the basis of human skeletal dysplasias with a wide range of phenotypic severity, from perinatal lethality to progressively deforming. This highly coordinated journey of chondrocyte specification and fate determination is controlled by a myriad of intrinsic and extrinsic factors. SOX9 is the master transcription factor that, in concert with varying partners along the way, directs the different phases of the journey from mesenchymal condensation, chondrogenesis, differentiation, proliferation, and maturation. Extracellular signals, including bone morphogenetic proteins, wingless-related MMTV integration site (WNT), fibroblast growth factor, Indian hedgehog, and parathyroid hormone-related peptide, are all indispensable for growth plate chondrocytes to align and organize into the appropriate columnar architecture and controls their maturation and transition to hypertrophy. Chondrocyte hypertrophy, marked by dramatic volume increase in phases, is controlled by transcription factors SOX9, Runt-related transcription factor, and FOXA2. Hypertrophic chondrocytes mediate the cartilage to bone transition and concomitantly face a live-or-die situation, a subject of much debate. We review recent insights into the coordination of the phases of the chondrocyte journey, and highlight the need for a systems level understanding of the regulatory networks that will facilitate the development of therapeutic approaches for skeletal dysplasia. Copyright © 2014 Wiley Periodicals

Aging and oxidative stress reduce the response of human articular chondrocytes to insulin-like growth factor 1 and osteogenic protein 1.

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Loeser, Richard F; Gandhi, Uma; Long, David L; Yin, Weihong; Chubinskaya, Susan

2014-08-01

To determine the effects of aging and oxidative stress on the response of human articular chondrocytes to insulin-like growth factor 1 (IGF-1) and osteogenic protein 1 (OP-1). Chondrocytes isolated from normal articular cartilage obtained from tissue donors were cultured in alginate beads or monolayer. Cells were stimulated with 50-100 ng/ml of IGF-1, OP-1, or both. Oxidative stress was induced using tert-butyl hydroperoxide. Sulfate incorporation was used to measure proteoglycan synthesis, and immunoblotting of cell lysates was performed to analyze cell signaling. Confocal microscopy was performed to measure nuclear translocation of Smad4. Chondrocytes isolated from the articular cartilage of tissue donors ranging in age from 24 years to 81 years demonstrated an age-related decline in proteoglycan synthesis stimulated by IGF-1 and IGF-1 plus OP-1. Induction of oxidative stress inhibited both IGF-1- and OP-1-stimulated proteoglycan synthesis. Signaling studies showed that oxidative stress inhibited IGF-1-stimulated Akt phosphorylation while increasing phosphorylation of ERK, and that these effects were greater in cells from older donors. Oxidative stress also increased p38 phosphorylation, which resulted in phosphorylation of Smad1 at the Ser(206) inhibitory site and reduced nuclear accumulation of Smad1. Oxidative stress also modestly reduced OP-1-stimulated nuclear translocation of Smad4. These results demonstrate an age-related reduction in the response of human chondrocytes to IGF-1 and OP-1, which are 2 important anabolic factors in cartilage, and suggest that oxidative stress may be a contributing factor by altering IGF-1 and OP-1 signaling. Copyright © 2014 by the American College of Rheumatology.

Stromal cell-derived factor 1 regulates the actin organization of chondrocytes and chondrocyte hypertrophy.

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Murata, Koichi; Kitaori, Toshiyuki; Oishi, Shinya; Watanabe, Naoki; Yoshitomi, Hiroyuki; Tanida, Shimei; Ishikawa, Masahiro; Kasahara, Takashi; Shibuya, Hideyuki; Fujii, Nobutaka; Nagasawa, Takashi; Nakamura, Takashi; Ito, Hiromu

2012-01-01

Stromal cell-derived factor 1 (SDF-1/CXCL12/PBSF) plays important roles in the biological and physiological functions of haematopoietic and mesenchymal stem cells. This chemokine regulates the formation of multiple organ systems during embryogenesis. However, its roles in skeletal development remain unclear. Here we investigated the roles of SDF-1 in chondrocyte differentiation. We demonstrated that SDF-1 protein was expressed at pre-hypertrophic and hypertrophic chondrocytes in the newly formed endochondral callus of rib fracture as well as in the growth plate of normal mouse tibia by immunohistochemical analysis. Using SDF-1(-/-) mouse embryo, we histologically showed that the total length of the whole humeri of SDF-1(-/-) mice was significantly shorter than that of wild-type mice, which was contributed mainly by shorter hypertrophic and calcified zones in SDF-1(-/-) mice. Actin cytoskeleton of hypertrophic chondrocytes in SDF-1(-/-) mouse humeri showed less F-actin and rounder shape than that of wild-type mice. Primary chondrocytes from SDF-1(-/-) mice showed the enhanced formation of philopodia and loss of F-actin. The administration of SDF-1 to primary chondrocytes of wild-type mice and SDF-1(-/-) mice promoted the formation of actin stress fibers. Organ culture of embryonic metatarsals from SDF-1(-/-) mice showed the growth delay, which was recovered by an exogenous administration of SDF-1. mRNA expression of type X collagen in metatarsals and in primary chondrocytes of SDF-1(-/-) mouse embryo was down-regulated while the administration of SDF-1 to metatarsals recovered. These data suggests that SDF-1 regulates the actin organization and stimulates bone growth by mediating chondrocyte hypertrophy.

Stromal cell-derived factor 1 regulates the actin organization of chondrocytes and chondrocyte hypertrophy.

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Koichi Murata

Full Text Available Stromal cell-derived factor 1 (SDF-1/CXCL12/PBSF plays important roles in the biological and physiological functions of haematopoietic and mesenchymal stem cells. This chemokine regulates the formation of multiple organ systems during embryogenesis. However, its roles in skeletal development remain unclear. Here we investigated the roles of SDF-1 in chondrocyte differentiation. We demonstrated that SDF-1 protein was expressed at pre-hypertrophic and hypertrophic chondrocytes in the newly formed endochondral callus of rib fracture as well as in the growth plate of normal mouse tibia by immunohistochemical analysis. Using SDF-1(-/- mouse embryo, we histologically showed that the total length of the whole humeri of SDF-1(-/- mice was significantly shorter than that of wild-type mice, which was contributed mainly by shorter hypertrophic and calcified zones in SDF-1(-/- mice. Actin cytoskeleton of hypertrophic chondrocytes in SDF-1(-/- mouse humeri showed less F-actin and rounder shape than that of wild-type mice. Primary chondrocytes from SDF-1(-/- mice showed the enhanced formation of philopodia and loss of F-actin. The administration of SDF-1 to primary chondrocytes of wild-type mice and SDF-1(-/- mice promoted the formation of actin stress fibers. Organ culture of embryonic metatarsals from SDF-1(-/- mice showed the growth delay, which was recovered by an exogenous administration of SDF-1. mRNA expression of type X collagen in metatarsals and in primary chondrocytes of SDF-1(-/- mouse embryo was down-regulated while the administration of SDF-1 to metatarsals recovered. These data suggests that SDF-1 regulates the actin organization and stimulates bone growth by mediating chondrocyte hypertrophy.

A standardized extract of Butea monosperma (Lam.) flowers suppresses the IL-1β-induced expression of IL-6 and matrix-metalloproteases by activating autophagy in human osteoarthritis chondrocytes.

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Ansari, Mohammad Y; Khan, Nazir M; Haqqi, Tariq M

2017-12-01

Osteoarthritis (OA) is a leading cause of joint dysfunction, disability and poor quality of life in the affected population. The underlying mechanism of joint dysfunction involves increased oxidative stress, inflammation, high levels of cartilage extracellular matrix degrading proteases and decline in autophagy-a mechanism of cellular defense. There is no disease modifying therapies currently available for OA. Different parts of the Butea monosperma (Lam.) plant have widely been used in the traditional Indian Ayurvedic medicine system for the treatment of various human diseases including inflammatory conditions. Here we studied the chondroprotective effect of hydromethanolic extract of Butea monosperma (Lam.) flowers (BME) standardized to the concentration of Butein on human OA chondrocytes stimulated with IL-1β. The hydromethanolic extract of Butea monosperma (Lam.) (BME) was prepared with 70% methanol-water mixer using Soxhlet. Chondrocytes viability after BME treatment was measured by MTT assay. Gene expression levels were determined by quantitative polymerase chain reaction (qPCR) using TaqMan assays and immunoblotting with specific antibodies. Autophagy activation was determined by measuring the levels of microtubule associated protein 1 light chain 3-II (LC3-II) by immunoblotting and visualization of autophagosomes by transmission electron and confocal microscopy. BME was non-toxic to the OA chondrocytes at the doses employed and suppressed the IL-1β induced expression of inerleukin-6 (IL-6) and matrix metalloprotease-3 (MMP-3), MMP-9 and MMP-13. BME enhanced autophagy in chondrocytes as determined by measuring the levels of LC3-II by immunoblotting and increased number of autophagosomes in BME treated chondrocytes by transmission electron microscopy and confocal microscopy. BME upregulated the expression of several autophagy related genes and increased the autophagy flux in human OA chondrocytes under pathological conditions. Further analysis revealed that

New bioreactor vessel for tissue engineering of human nasal septal chondrocytes

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Princz Sascha

2016-09-01

Full Text Available Cultivation of human nasal septal chondrocytes in a self-established automated bioreactor system with a new designed reactor glass vessel and the results of a computational fluid dynamics model are presented. The first results show the effect of a homogeneous fluidic condition of the continuous medium flow and the resulting stresses on the scaffolds’ surface and their influence on the migration of the cells into the scaffold matrix under these conditions. For this purpose computational models, generated with the computational fluid dynamics software STAR-CCM+, and the results of alcian blue staining for newly synthesized sulphated glycosaminoglycans have been compared during cultivation in the new and a first version of the glass reactor vessel with inhomogeneous fluidic conditions, with the same automated bioreactor system and under similar cultivation conditions.

Effect of microcavitary alginate hydrogel with different pore sizes on chondrocyte culture for cartilage tissue engineering

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Zeng, Lei; Yao, Yongchang; Wang, Dong-an; Chen, Xiaofeng

2014-01-01

In our previous work, a novel microcavitary hydrogel was proven to be effective for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we further investigated whether the size of microcavity would affect the growth and the function of chondrocytes. By changing the stirring rate, gelatin microspheres in different sizes including small size (80–120 μm), middle size (150–200 μm) and large size (250–300 μm) were prepared. And then porcine chondrocytes were encapsulated into alginate hydrogel with various sizes of gelatin microspheres. Cell Counting Kit-8 (CCK-8), Live/dead staining and real-time PCR were used to analyze the effect of the pore size on cell proliferation and expression of specific chondrocytic genes. According to all the data, cells cultivated in microcavitary hydrogel, especially in small size, had preferable abilities of proliferation and higher expression of cartilaginous markers including type II collagen, aggrecan and cartilage oligomeric matrix protein (COMP). Furthermore, it was shown by western blot assay that the culture of chondrocytes in microcavitary hydrogel could improve the proliferation of cells potentially by inducing the Erk1/2-MAPK pathway. Taken together, this study demonstrated that chondrocytes favored microcavitary alginate hydrogel with pore size within the range of 80–120 μm for better growth and ECM synthesis, in which Erk1/2 pathway was involved. This culture system would be promising for cartilage tissue engineering. - Highlights: • A novel model with microcavitary structure was set up to study the interaction between cells and materials. • Microcavitary alginate hydrogel could enhance the proliferation of chondrocytes and promote the expression of cartilaginous genes as compared with plain alginate hydrogel. • Cells in microcavitary alginate hydrogel with pore size within the range of 80–120 μm were capable of better growth and ECM synthesis

Effect of microcavitary alginate hydrogel with different pore sizes on chondrocyte culture for cartilage tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Zeng, Lei; Yao, Yongchang [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Wang, Dong-an, E-mail: DAWang@ntu.edu.sg [National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457 (Singapore); Chen, Xiaofeng, E-mail: chenxf@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China)

2014-01-01

In our previous work, a novel microcavitary hydrogel was proven to be effective for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we further investigated whether the size of microcavity would affect the growth and the function of chondrocytes. By changing the stirring rate, gelatin microspheres in different sizes including small size (80–120 μm), middle size (150–200 μm) and large size (250–300 μm) were prepared. And then porcine chondrocytes were encapsulated into alginate hydrogel with various sizes of gelatin microspheres. Cell Counting Kit-8 (CCK-8), Live/dead staining and real-time PCR were used to analyze the effect of the pore size on cell proliferation and expression of specific chondrocytic genes. According to all the data, cells cultivated in microcavitary hydrogel, especially in small size, had preferable abilities of proliferation and higher expression of cartilaginous markers including type II collagen, aggrecan and cartilage oligomeric matrix protein (COMP). Furthermore, it was shown by western blot assay that the culture of chondrocytes in microcavitary hydrogel could improve the proliferation of cells potentially by inducing the Erk1/2-MAPK pathway. Taken together, this study demonstrated that chondrocytes favored microcavitary alginate hydrogel with pore size within the range of 80–120 μm for better growth and ECM synthesis, in which Erk1/2 pathway was involved. This culture system would be promising for cartilage tissue engineering. - Highlights: • A novel model with microcavitary structure was set up to study the interaction between cells and materials. • Microcavitary alginate hydrogel could enhance the proliferation of chondrocytes and promote the expression of cartilaginous genes as compared with plain alginate hydrogel. • Cells in microcavitary alginate hydrogel with pore size within the range of 80–120 μm were capable of better growth and ECM synthesis.

Influence of cell printing on biological characters of chondrocytes.

Science.gov (United States)

Qu, Miao; Gao, Xiaoyan; Hou, Yikang; Shen, Congcong; Xu, Yourong; Zhu, Ming; Wang, Hengjian; Xu, Haisong; Chai, Gang; Zhang, Yan

2015-01-01

To establish a two-dimensional biological printing technique of chondrocytes and compare the difference of related biological characters between printed chondrocytes and unprinted cells so as to control the cell transfer process and keep cell viability after printing. Primary chondrocytes were obtained from human mature and fetal cartilage tissues and then were regularly sub-cultured to harvest cells at passage 2 (P2), which were adjusted to the single cell suspension at a density of 1×10(6)/mL. The experiment was divided into 2 groups: experimental group P2 chondrocytes were transferred by rapid prototype biological printer (driving voltage value 50 V, interval in x-axis 300 μm, interval in y-axis 1500 μm). Afterwards Live/Dead viability Kit and flow cytometry were respectively adopted to detect cell viability; CCK-8 Kit was adopted to detect cell proliferation viability; immunocytochemistry, immunofluorescence and RT-PCR was employed to identify related markers of chondrocytes; control group steps were the same as the printing group except that cell suspension received no printing. Fluorescence microscopy and flow cytometry analyses showed that there was no significant difference between experimental group and control group in terms of cell viability. After 7-day in vitro culture, control group exhibited higher O.D values than experimental group from 2nd day to 7th day but there was no distinct difference between these two groups (P>0.05). Inverted microscope observation demonstrated that the morphology of these two groups had no significant difference either. Similarly, Immunocytochemistry, immunofluorescence and RT-PCR assays also showed that there was no significant difference in the protein and gene expression of type II collagen and aggrecan between these two groups (P>0.05). Conclusion Cell printing has no distinctly negative effect on cell vitality, proliferation and phenotype of chondrocytes. Biological printing technique may provide a novel approach

IKKα/CHUK regulates extracellular matrix remodeling independent of its kinase activity to facilitate articular chondrocyte differentiation.

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Eleonora Olivotto

Full Text Available BACKGROUND: The non-canonical NF-κB activating kinase IKKα, encoded by CHUK (conserved-helix-loop-helix-ubiquitous-kinase, has been reported to modulate pro- or anti- inflammatory responses, cellular survival and cellular differentiation. Here, we have investigated the mechanism of action of IKKα as a novel effector of human and murine chondrocyte extracellular matrix (ECM homeostasis and differentiation towards hypertrophy. METHODOLOGY/PRINCIPAL FINDINGS: IKKα expression was ablated in primary human osteoarthritic (OA chondrocytes and in immature murine articular chondrocytes (iMACs derived from IKKα(f/f:CreERT2 mice by retroviral-mediated stable shRNA transduction and Cre recombinase-dependent Lox P site recombination, respectively. MMP-10 was identified as a major target of IKKα in chondrocytes by mRNA profiling, quantitative RT-PCR analysis, immunohistochemistry and immunoblotting. ECM integrity, as assessed by type II collagen (COL2 deposition and the lack of MMP-dependent COL2 degradation products, was enhanced by IKKα ablation in mice. MMP-13 and total collagenase activities were significantly reduced, while TIMP-3 (tissue inhibitor of metalloproteinase-3 protein levels were enhanced in IKKα-deficient chondrocytes. IKKα deficiency suppressed chondrocyte differentiation, as shown by the quantitative inhibition of.Alizarin red staining and the reduced expression of multiple chondrocyte differentiation effectors, including Runx2, Col10a1 and Vegfa,. Importantly, the differentiation of IKKα-deficient chondrocytes was rescued by a kinase-dead IKKα protein mutant. CONCLUSIONS/SIGNIFICANCE: IKKα acts independent of its kinase activity to help drive chondrocyte differentiation towards a hypertrophic-like state. IKKα positively modulates ECM remodeling via multiple downstream targets (including MMP-10 and TIMP-3 at the mRNA and post-transcriptional levels, respectively to maintain maximal MMP-13 activity, which is required for ECM

Oxidative Stress Promotes Peroxiredoxin Hyperoxidation and Attenuates Pro-survival Signaling in Aging Chondrocytes*

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Collins, John A.; Wood, Scott T.; Nelson, Kimberly J.; Rowe, Meredith A.; Carlson, Cathy S.; Chubinskaya, Susan; Poole, Leslie B.; Furdui, Cristina M.; Loeser, Richard F.

2016-01-01

Oxidative stress-mediated post-translational modifications of redox-sensitive proteins are postulated as a key mechanism underlying age-related cellular dysfunction and disease progression. Peroxiredoxins (PRX) are critical intracellular antioxidants that also regulate redox signaling events. Age-related osteoarthritis is a common form of arthritis that has been associated with mitochondrial dysfunction and oxidative stress. The objective of this study was to determine the effect of aging and oxidative stress on chondrocyte intracellular signaling, with a specific focus on oxidation of cytosolic PRX2 and mitochondrial PRX3. Menadione was used as a model to induce cellular oxidative stress. Compared with chondrocytes isolated from young adult humans, chondrocytes from older adults exhibited higher levels of PRX1–3 hyperoxidation basally and under conditions of oxidative stress. Peroxiredoxin hyperoxidation was associated with inhibition of pro-survival Akt signaling and stimulation of pro-death p38 signaling. These changes were prevented in cultured human chondrocytes by adenoviral expression of catalase targeted to the mitochondria (MCAT) and in cartilage explants from MCAT transgenic mice. Peroxiredoxin hyperoxidation was observed in situ in human cartilage sections from older adults and in osteoarthritic cartilage. MCAT transgenic mice exhibited less age-related osteoarthritis. These findings demonstrate that age-related oxidative stress can disrupt normal physiological signaling and contribute to osteoarthritis and suggest peroxiredoxin hyperoxidation as a potential mechanism. PMID:26797130

Chondrocyte-specific ablation of Osterix leads to impaired endochondral ossification

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Oh, Jung-Hoon [Department of Molecular Medicine, Cell and Matrix Research Institute, BK21 Medical Education Program for Human Resources, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Park, Seung-Yoon [Department of Biochemistry, School of Medicine, Dongguk University, Gyeongju 780-714 (Korea, Republic of); Crombrugghe, Benoit de [Department of Genetics, University of Texas, M.D. Anderson Cancer Center, Houston (United States); Kim, Jung-Eun, E-mail: kjeun@knu.ac.kr [Department of Molecular Medicine, Cell and Matrix Research Institute, BK21 Medical Education Program for Human Resources, Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

2012-02-24

Highlights: Black-Right-Pointing-Pointer Conditional ablation of Osterix (Osx) in chondrocytes leads to skeletal defects. Black-Right-Pointing-Pointer Osx regulates chondrocyte differentiation and bone growth in growth plate chondrocytes. Black-Right-Pointing-Pointer Osx has an autonomous function in chondrocytes during endochondral ossification. -- Abstract: Osterix (Osx) is an essential transcription factor required for osteoblast differentiation during both intramembranous and endochondral ossification. Endochondral ossification, a process in which bone formation initiates from a cartilage intermediate, is crucial for skeletal development and growth. Osx is expressed in differentiating chondrocytes as well as osteoblasts during mouse development, but its role in chondrocytes has not been well studied. Here, the in vivo function of Osx in chondrocytes was examined in a chondrocyte-specific Osx conditional knockout model using Col2a1-Cre. Chondrocyte-specific Osx deficiency resulted in a weak and bent skeleton which was evident in newborn by radiographic analysis and skeletal preparation. To further understand the skeletal deformity of the chondrocyte-specific Osx conditional knockout, histological analysis was performed on developing long bones during embryogenesis. Hypertrophic chondrocytes were expanded, the formation of bone trabeculae and marrow cavities was remarkably delayed, and subsequent skeletal growth was reduced. The expression of several chondrocyte differentiation markers was reduced, indicating the impairment of chondrocyte differentiation and endochondral ossification in the chondrocyte-specific Osx conditional knockout. Taken together, Osx regulates chondrocyte differentiation and bone growth in growth plate chondrocytes, suggesting an autonomous function of Osx in chondrocytes during endochondral ossification.

Bovine lactoferricin induces TIMP-3 via the ERK1/2-Sp1 axis in human articular chondrocytes.

Science.gov (United States)

Yan, Dongyao; Chen, Di; Hawse, John R; van Wijnen, Andre J; Im, Hee-Jeong

2013-03-15

Bovine lactoferricin (LfcinB) is a heparan sulfate-binding peptide with multiple bioactivities. In human articular cartilage, LfcinB antagonizes interleukin-1 β (IL-1β) and fibroblast growth factor 2 (FGF-2) in proteoglycan metabolism, catabolic protease expression, and induction of pro-inflammatory mediators. LfcinB specifically activates ERK1/2, p38 and Akt, but whether these signaling pathways control the expression of LfcinB target genes remained unknown. In this report, we characterized a novel aspect of LfcinB-mediated genetic response in human articular chondrocytes, tissue inhibitor of metalloproteinase 3 (TIMP-3) induction. Inhibition of individual signaling pathways revealed that ERK1/2 functions as the major pathway in TIMP-3 expression, whereas Akt plays a minor role. Further investigation identified Sp1 as a critical transcriptional activator in TIMP-3 regulation, and Sp1 activity is modulated by ERK1/2, not Akt. Comparative quantification indicates that significant downregulation of TIMP-3 occurs in OA chondrocytes, suggesting a beneficial role of LfcinB in OA pathogenesis. Our results collectively provide new insights into the mechanism of action of LfcinB, and support the candidacy of LfcinB as a chondroprotective agent. Copyright © 2013 Elsevier B.V. All rights reserved.

Culture of chondrocytes in alginate surrounded by fibrin gel: characteristics of the cells over a period of eight weeks

NARCIS (Netherlands)

Almqvist, K. F.; Wang, L.; Wang, J.; Baeten, D.; Cornelissen, M.; Verdonk, R.; Veys, E. M.; Verbruggen, G.

2001-01-01

OBJECTIVE: To produce tissue engineered cartilage by human articular chondrocytes in vitro for further use in in vivo manipulations for the treatment of cartilage defects. METHODS: Human articular chondrocytes were cultured in 0.5%, 1.0%, and 2.0% of alginate for up to four weeks. The optimal

Primary chondrocytes enhance cartilage tissue formation upon co-culture with expanded chondrocytes, dermal fibroblasts, 3T3 feeder cells and embryonic stem cells

NARCIS (Netherlands)

Hendriks, J.A.A.; Miclea, Razvan L.; Schotel, Roka; de Bruijn, Ewart; Moroni, Lorenzo; Karperien, Hermanus Bernardus Johannes; Riesle, J.U.; van Blitterswijk, Clemens

2010-01-01

Co-culture models have been increasingly used in tissue engineering applications to understand cell–cell interactions and consequently improve regenerative medicine strategies. Aiming at further elucidating cartilage tissue formation, we co-cultured bovine primary chondrocytes (BPCs) with human

Applications of Chondrocyte-Based Cartilage Engineering: An Overview

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Abdul-Rehman Phull

2016-01-01

Full Text Available Chondrocytes are the exclusive cells residing in cartilage and maintain the functionality of cartilage tissue. Series of biocomponents such as different growth factors, cytokines, and transcriptional factors regulate the mesenchymal stem cells (MSCs differentiation to chondrocytes. The number of chondrocytes and dedifferentiation are the key limitations in subsequent clinical application of the chondrocytes. Different culture methods are being developed to overcome such issues. Using tissue engineering and cell based approaches, chondrocytes offer prominent therapeutic option specifically in orthopedics for cartilage repair and to treat ailments such as tracheal defects, facial reconstruction, and urinary incontinence. Matrix-assisted autologous chondrocyte transplantation/implantation is an improved version of traditional autologous chondrocyte transplantation (ACT method. An increasing number of studies show the clinical significance of this technique for the chondral lesions treatment. Literature survey was carried out to address clinical and functional findings by using various ACT procedures. The current study was conducted to study the pharmacological significance and biomedical application of chondrocytes. Furthermore, it is inferred from the present study that long term follow-up studies are required to evaluate the potential of these methods and specific positive outcomes.

An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films

International Nuclear Information System (INIS)

Antonioli, Eliane; Lobo, Anderson O.; Ferretti, Mario; Cohen, Moisés; Marciano, Fernanda R.; Corat, Evaldo J.; Trava-Airoldi, Vladimir J.

2013-01-01

Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O 2 plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Highlights: ► Chondrocytes were cultivated on Superhydrophilic Vertically Aligned Multiwall Carbon Nanotubes (VACNT). ► We have shown a correlation between gene expression and thermodynamics aspects. ► Superhydrhophilic VACNT will be an excellent substrate for cartilage and bone tissue regeneration.

An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films

Energy Technology Data Exchange (ETDEWEB)

Antonioli, Eliane, E-mail: eliane.antonioli@einstein.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Lobo, Anderson O., E-mail: aolobo@univap.br [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Ferretti, Mario, E-mail: ferretti@einstein.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Cohen, Moises, E-mail: m.cohen@uol.com.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Marciano, Fernanda R., E-mail: femarciano@uol.com.br [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Corat, Evaldo J., E-mail: corat@las.inpe.br [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil); Trava-Airoldi, Vladimir J., E-mail: vladimir@las.inpe.br [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil)

2013-03-01

Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O{sub 2} plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Highlights: Black-Right-Pointing-Pointer Chondrocytes were cultivated on Superhydrophilic Vertically Aligned Multiwall Carbon Nanotubes (VACNT). Black-Right-Pointing-Pointer We have shown a correlation between gene expression and thermodynamics aspects. Black-Right-Pointing-Pointer Superhydrhophilic VACNT will be an excellent substrate for cartilage and bone tissue regeneration.

Doublecortin May Play a Role in Defining Chondrocyte Phenotype

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Dongxia Ge

2014-04-01

Full Text Available Embryonic development of articular cartilage has not been well understood and the role of doublecortin (DCX in determination of chondrocyte phenotype is unknown. Here, we use a DCX promoter-driven eGFP reporter mouse model to study the dynamic gene expression profiles in mouse embryonic handplates at E12.5 to E13.5 when the condensed mesenchymal cells differentiate into either endochondral chondrocytes or joint interzone cells. Illumina microarray analysis identified a variety of genes that were expressed differentially in the different regions of mouse handplate. The unique expression patterns of many genes were revealed. Cytl1 and 3110032G18RIK were highly expressed in the proximal region of E12.5 handplate and the carpal region of E13.5 handplate, whereas Olfr538, Kctd15, and Cited1 were highly expressed in the distal region of E12.5 and the metacarpal region of E13.5 handplates. There was an increasing gradient of Hrc expression in the proximal to distal direction in E13.5 handplate. Furthermore, when human DCX protein was expressed in human adipose stem cells, collagen II was decreased while aggrecan, matrilin 2, and GDF5 were increased during the 14-day pellet culture. These findings suggest that DCX may play a role in defining chondrocyte phenotype.

An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films.

Science.gov (United States)

Antonioli, Eliane; Lobo, Anderson O; Ferretti, Mario; Cohen, Moisés; Marciano, Fernanda R; Corat, Evaldo J; Trava-Airoldi, Vladimir J

2013-03-01

Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O2 plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Copyright © 2012 Elsevier B.V. All rights reserved.

Chondrocyte behavior on nanostructured micropillar polypropylene and polystyrene surfaces

Energy Technology Data Exchange (ETDEWEB)

Prittinen, Juha [Department of Applied Physics, University of Eastern Finland, Kuopio (Finland); Jiang, Yu [Department of Chemistry, University of Eastern Finland, Joensuu (Finland); Ylärinne, Janne H. [Department of Applied Physics, University of Eastern Finland, Kuopio (Finland); Pakkanen, Tapani A. [Department of Chemistry, University of Eastern Finland, Joensuu (Finland); Lammi, Mikko J., E-mail: mikko.lammi@uef.fi [Department of Applied Physics, University of Eastern Finland, Kuopio (Finland); Qu, Chengjuan [Department of Applied Physics, University of Eastern Finland, Kuopio (Finland)

2014-10-01

This study was aimed to investigate whether patterned polypropylene (PP) or polystyrene (PS) could enhance the chondrocytes' extracellular matrix (ECM) production and phenotype maintenance. Bovine primary chondrocytes were cultured on smooth PP and PS, as well as on nanostructured micropillar PP (patterned PP) and PS (patterned PS) for 2 weeks. Subsequently, the samples were collected for fluorescein diacetate-based cell viability tests, for immunocytochemical assays of types I and II collagen, actin and vinculin, for scanning electronic microscopic analysis of cell morphology and distribution, and for gene expression assays of Sox9, aggrecan, procollagen α{sub 1}(II), procollagen α{sub 1}(X), and procollagen α{sub 2}(I) using quantitative RT-PCR assays. After two weeks of culture, the bovine primary chondrocytes had attached on both patterned PP and PS, while practically no adhesion was observed on smooth PP. However, the best adhesion of the cells was on smooth PS. The cells, which attached on patterned PP and PS surfaces synthesized types I and II collagen. The chondrocytes' morphology was extended, and an abundant ECM network formed around the attached chondrocytes on both patterned PP and PS. Upon passaging, no significant differences on the chondrocyte-specific gene expression were observed, although the highest expression level of aggrecan was observed on the patterned PS in passage 1 chondrocytes, and the expression level of procollagen α{sub 1}(II) appeared to decrease in passaged chondrocytes. However, the expressions of procollagen α{sub 2}(I) were increased in all passaged cell cultures. In conclusion, the bovine primary chondrocytes could be grown on patterned PS and PP surfaces, and they produced extracellular matrix network around the adhered cells. However, neither the patterned PS nor PP could prevent the dedifferentiation of chondrocytes. - Highlights: • Methods to avoid chondrocyte dedifferentiation would be useful for cartilage

ICAM-1 expression on chondrocytes in rheumatoid arthritis: induction by synovial cytokines

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M. E. Davies

1992-01-01

Full Text Available The intercellular adhesion molecule-1 (ICAM-1 was found by immunostaining chondrocytes in cartilage from three patients with rheumatoid arthritis. Expression of ICAM-1 was restricted to chondrocytes in areas of erodedcartilage adjacent to the invading synovial tissue. Toluidine blue staining of these areas demonstrated severe depletion of the cartilage extracellular matrix. In areas of undamaged cartilage there was no ICAM-1 expression. Since ICAM-1 is not constitutively expressed on normal human articular cartilage, but could be induced in vitro by exogenous IL-1α, TNFα and IFNγ or by co-culturing cartilage with inflammatory rheumatoid synovium, we conclude that the induction of ICAM-1 on rheumatoid chondrocytes results from the synergistic action of a variety of cytokines produced by the inflammatory cells of the invading pannus.

5-Aza-2'-deoxycytidine acts as a modulator of chondrocyte hypertrophy and maturation in chick caudal region chondrocytes in culture.

Science.gov (United States)

Haq, Samina Hyder

2016-06-01

This study was carried out to explore the effect of DNA hypomethylation on chondrocytes phenotype, in particular the effect on chondrocyte hypertrophy, maturation, and apoptosis. Chondrocytes derived from caudal region of day 17 embryonic chick sterna were pretreated with hypomethylating drug 5-aza-2'-deoxycytidine for 48 hours and then maintained in the normal culture medium for up to 14 days. Histological studies showed distinct morphological changes occurred in the pretreated cultures when compared to the control cultures. The pretreated chondrocytes after 7 days in culture became bigger in size and acquired more flattened fibroblastic phenotype as well as a loss of cartilage specific extracellular matrix. Scanning electron microscopy at day 7 showed chondrocytes to have increased in cell volume and at day 14 in culture the extracellular matrix of the pretreated cultures showed regular fibrillar structure heavily embedded with matrix vesicles, which is the characteristic feature of chondrocyte hypertrophy. Transmission electron microscopic studies indicated the terminal fate of the hypertrophic cells in culture. The pretreated chondrocytes grown for 14 days in culture showed two types of cells: dark cells which had condense chromatin in dark patches and dark cytoplasm. The other light chondrocytes appeared to be heavily loaded with endoplasmic reticulum indicative of very active protein and secretory activity; their cytoplasm had large vacuoles and disintegrating cytoplasm. The biosynthetic profile showed that the pretreated cultures were actively synthesizing and secreting type X collagen and alkaline phosphatase as a major biosynthetic product.

In vitro evaluation of chondrosarcoma cells and canine chondrocytes on layer-by-layer (LbL) self-assembled multilayer nanofilms

International Nuclear Information System (INIS)

Shaik, J; Mohammed, J Shaikh; McShane, M J; Mills, D K

2013-01-01

Short-term cell–substrate interactions of two secondary chondrocyte cell lines (human chondrosarcoma cells, canine chondrocytes) with layer-by-layer self-assembled multilayer nanofilms were investigated for a better understanding of cellular-behaviour dependence on a number of nanofilm layers. Cell–substrate interactions were studied on polyelectrolyte multilayer nanofilms (PMNs) of eleven different biomaterials. Surface characterization of PMNs performed using AFM showed increasing surface roughness with increasing number of layers for most of the biomaterials. LDH-L and MTT assays were performed on chondrosarcoma cells and canine chondrocytes, respectively. A major observation was that 10-bilayer nanofilms exhibited lesser cytotoxicity towards human chondrosarcoma cells than their 5-bilayer counterparts. In the case of canine chondrocytes, BSA enhanced cell metabolic activity with increasing number of layers, underscoring the importance of the multilayer nanofilm architecture on cellular behaviour. (paper)

Cellular automata model for human articular chondrocytes migration, proliferation and cell death: An in vitro validation.

Science.gov (United States)

Vaca-González, J J; Gutiérrez, M L; Guevara, J M; Garzón-Alvarado, D A

2017-01-01

Articular cartilage is characterized by low cell density of only one cell type, chondrocytes, and has limited self-healing properties. When articular cartilage is affected by traumatic injuries, a therapeutic strategy such as autologous chondrocyte implantation is usually proposed for its treatment. This approach requires in vitro chondrocyte expansion to yield high cell number for cell transplantation. To improve the efficiency of this procedure, it is necessary to assess cell dynamics such as migration, proliferation and cell death during culture. Computational models such as cellular automata can be used to simulate cell dynamics in order to enhance the result of cell culture procedures. This methodology has been implemented for several cell types; however, an experimental validation is required for each one. For this reason, in this research a cellular automata model, based on random-walk theory, was devised in order to predict articular chondrocyte behavior in monolayer culture during cell expansion. Results demonstrated that the cellular automata model corresponded to cell dynamics and computed-accurate quantitative results. Moreover, it was possible to observe that cell dynamics depend on weighted probabilities derived from experimental data and cell behavior varies according to the cell culture period. Thus, depending on whether cells were just seeded or proliferated exponentially, culture time probabilities differed in percentages in the CA model. Furthermore, in the experimental assessment a decreased chondrocyte proliferation was observed along with increased passage number. This approach is expected to having other uses as in enhancing articular cartilage therapies based on tissue engineering and regenerative medicine.

Effect of chondrocyte-derived early extracellular matrix on chondrogenesis of placenta-derived mesenchymal stem cells.

Science.gov (United States)

Park, Yong-Beom; Seo, Sinji; Kim, Jin-A; Heo, Jin-Chul; Lim, Young-Cheol; Ha, Chul-Won

2015-06-24

The extracellular matrix (ECM) surrounding cells contains a variety of proteins that provide structural support and regulate cellular functions. Previous studies have shown that decellularized ECM isolated from tissues or cultured cells can be used to improve cell differentiation in tissue engineering applications. In this study we evaluated the effect of decellularized chondrocyte-derived ECM (CDECM) on the chondrogenesis of human placenta-derived mesenchymal stem cells (hPDMSCs) in a pellet culture system. After incubation with or without chondrocyte-derived ECM in chondrogenic medium for 1 or 3 weeks, the sizes and wet masses of the cell pellets were compared with untreated controls (hPDMSCs incubated in chondrogenic medium without chondrocyte-derived ECM). In addition, histologic analysis of the cell pellets (Safranin O and collagen type II staining) and quantitative reverse transcription-PCR analysis of chondrogenic markers (aggrecan, collagen type II, and SOX9) were carried out. Our results showed that the sizes and masses of hPDMSC pellets incubated with chondrocyte-derived ECM were significantly higher than those of untreated controls. Differentiation of hPDMSCs (both with and without chondrocyte-derived ECM) was confirmed by Safranin O and collagen type II staining. Chondrogenic marker expression and glycosaminoglycan (GAG) levels were significantly higher in hPDMSC pellets incubated with chondrocyte-derived ECM compared with untreated controls, especially in cells precultured with chondrocyte-derived ECM for 7 d. Taken together, these results demonstrate that chondrocyte-derived ECM enhances the chondrogenesis of hPDMSCs, and this effect is further increased by preculture with chondrocyte-derived ECM. This preculture method for hPDMSC chondrogenesis represents a promising approach for cartilage tissue engineering.

New insight on FGFR3-related chondrodysplasias molecular physiopathology revealed by human chondrocyte gene expression profiling.

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Laurent Schibler

Full Text Available Endochondral ossification is the process by which the appendicular skeleton, facial bones, vertebrae and medial clavicles are formed and relies on the tight control of chondrocyte maturation. Fibroblast growth factor receptor (FGFR3 plays a role in bone development and maintenance and belongs to a family of proteins which differ in their ligand affinities and tissue distribution. Activating mutations of the FGFR3 gene lead to craniosynostosis and multiple types of skeletal dysplasia with varying degrees of severity: thanatophoric dysplasia (TD, achondroplasia and hypochondroplasia. Despite progress in the characterization of FGFR3-mediated regulation of cartilage development, many aspects remain unclear. The aim and the novelty of our study was to examine whole gene expression differences occurring in primary human chondrocytes isolated from normal cartilage or pathological cartilage from TD-affected fetuses, using Affymetrix technology. The phenotype of the primary cells was confirmed by the high expression of chondrocytic markers. Altered expression of genes associated with many cellular processes was observed, including cell growth and proliferation, cell cycle, cell adhesion, cell motility, metabolic pathways, signal transduction, cell cycle process and cell signaling. Most of the cell cycle process genes were down-regulated and consisted of genes involved in cell cycle progression, DNA biosynthesis, spindle dynamics and cytokinesis. About eight percent of all modulated genes were found to impact extracellular matrix (ECM structure and turnover, especially glycosaminoglycan (GAG and proteoglycan biosynthesis and sulfation. Altogether, the gene expression analyses provide new insight into the consequences of FGFR3 mutations in cell cycle regulation, onset of pre-hypertrophic differentiation and concomitant metabolism changes. Moreover, impaired motility and ECM properties may also provide clues about growth plate disorganization. These

The Results of Fetal Chondrocytes Transplantation in Patients with Rheumatoid Arthritis

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Natalya Krivoruchko

2014-12-01

Full Text Available Introduction. Nowadays anti-inflammatory and immunosuppressive therapy has significantly improved the quality of life and prognosis of rheumatoid arthritis (RA. Nevertheless, there are still many patients with progressive rheumatoid inflammation, resulting in the destruction of joints. Cell therapy seems like a promising direction in rheumatology. The aim of our research was to evaluate the efficacy of fetal chondrocyte transplantation in patients with RA.Methods. We examined 60 patients with rheumatoid arthritis (I - III stages between 20 and 63 years of age. They were divided into 2 groups: the first group underwent the fetal chondrocytes transplantation (n = 40, and the second was a control group who got conservative therapy (n = 20. Donor cells were taken from the chondrogenic layer of the humerus or femur heads and hip condyles of human embryos in gestation for 17-20 weeks. A suspension of fetal chondrocytes injected into affected areas of the articular surfaces under X-ray control. Cell viability was determined before the injection. Efficacy of the therapy was assessed by clinical, instrumental, and laboratory tests. This clinical trial was allowed by The Ministry of Public Health and Ethics Committee. All of our patients gave informed consent for the fetal chondrocytes transplantation.Results. Evaluation of the clinical manifestations of RA in the first group of patients showed 3.7 times decrease in pain and 1.6 times relief of synovitis. Complete reduction of contracture was observed in 82% of patients in the first group. Morphometric changes in X-ray demonstrated inhibition of the destruction in articular cartilage and surfaces of bones after transplantation of fetal chondrocytes. The dynamics of morphological changes in synovium showed 2.5 times reduction of the inflammatory reaction. Transplantation of fetal chondrocytes led to a significant reduction in ESR, CRP, fibrinogen , γ-globulin after a period of 12 months (p < 0

ADAM12-S stimulates bone growth in transgenic mice by modulating chondrocyte proliferation and maturation

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Kveiborg, Marie; Albrechtsen, Reidar; Rudkjaer, Lise

2006-01-01

ADAM12-S transgenic mice exhibit a pronounced increase in the length of bones, such as femur, tibia, and vertebrae. The effect of ADAM12-S on longitudinal bone growth involves the modulation of chondrocyte proliferation and maturation, likely through proteolytic activities and altered cell......: Transgenic mice expressing the secreted form of human ADAM12, ADAM12-S, or a truncated metalloprotease-deficient form of ADAM12-S in the circulation were used to study the effects of ADAM12 on the skeleton. In addition, murine chondrocyte cultures were used to study the effect of ADAM12-S on cell...... studies showed that ADAM12-S inhibits chondrocyte adhesion to fibronectin and collagen type II. CONCLUSIONS: ADAM12-S stimulates bone growth in mice by modulating chondrocyte proliferation and maturation through mechanisms probably involving both metalloprotease and adhesion activities....

Effect of a Herbal-Leucine mix on the IL-1β-induced cartilage degradation and inflammatory gene expression in human chondrocytes

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Haqqi Tariq M

2011-08-01

Full Text Available Abstract Background Conventional treatments for the articular diseases are often effective for symptom relief, but can also cause significant side effects and do not slow the progression of the disease. Several natural substances have been shown to be effective at relieving the symptoms of osteoarthritis (OA, and preliminary evidence suggests that some of these compounds may exert a favorable influence on the course of the disease. The objective of this study was to investigate the anti-inflammatory/chondroprotective potential of a Herbal and amino acid mixture containing extract of the Uncaria tomentosa, Boswellia spp., Lepidium meyenii and L-Leucine on the IL-1β-induced production of nitric oxide (NO, glycosaminoglycan (GAG, matrix metalloproteinases (MMPs, aggrecan (ACAN and type II collagen (COL2A1 in human OA chondrocytes and OA cartilage explants. Methods Primary OA chondrocytes or OA cartilage explants were pretreated with Herbal-Leucine mixture (HLM, 1-10 μg/ml and then stimulated with IL-1β (5 ng/ml. Effect of HLM on IL-1β-induced gene expression of iNOS, MMP-9, MMP-13, ACAN and COL2A1 was verified by real time-PCR. Estimation of NO and GAG release in culture supernatant was done using commercially available kits. Results HLM tested in these in vitro studies was found to be an effective anti-inflammatory agent, as evidenced by strong inhibition of iNOS, MMP-9 and MMP-13 expression and NO production in IL-1β-stimulated OA chondrocytes (p Leucine mixture (HLM up-regulation of ACAN and COL2A1 expression in IL-1β-stimulated OA chondrocytes was also noted (p Conclusion Our data suggests that HLM could be chondroprotective and anti-inflammatory agent in arthritis, switching chondrocyte gene expression from catabolic direction towards anabolic and regenerative, and consequently this approach may be potentially useful as a new adjunct therapeutic/preventive agent for OA or injury recovery.

NF-κB Mediates the Stimulation of Cytokine and Chemokine Expression by Human Articular Chondrocytes in Response to Fibronectin Fragments1

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Pulai, Judit I.; Chen, Hong; Im, Hee-Jeong; Kumar, Sanjay; Hanning, Charles; Hegde, Priti S.; Loeser, Richard F.

2010-01-01

Fibronectin fragments (FN-f) that bind to the α5β1 integrin stimulate chondrocyte-mediated cartilage destruction and could play an important role in the progression of arthritis. The objective of this study was to identify potential cytokine mediators of cartilage inflammation and destruction induced by FN-f and to investigate the mechanism of their stimulation. Human articular chondrocytes, isolated from normal ankle cartilage obtained from tissue donors, were treated with a 110-kDa FN-f in serum-free culture, and expression of various cytokine genes was analyzed by cDNA microarray and by a cytokine protein array. Compared with untreated control cultures, stimulation by FN-f resulted in a >2-fold increase in IL-6, IL-8, MCP-1, and growth-related oncogene β (GRO-β). Constitutive and FN-f-inducible expression of GRO-α and GRO-γ were also noted by RT-PCR and confirmed by immunoblotting. Previous reports of IL-1β expression induced by FN-f were also confirmed, while TNF expression was found to be very low. Inhibitor studies revealed that FN-f-induced stimulation of chondrocyte chemokine expression was dependent on NF-κB activity, but independent of IL-1 autocrine signaling. The ability of FN-f to stimulate chondrocyte expression of multiple proinflammatory cytokines and chemokines suggests that damage to the cartilage matrix is capable of inducing a proinflammatory state responsible for further progressive matrix destruction, which also includes the chemoattraction of inflammatory cells. Targeting the signaling pathways activated by FN-f may be an effective means of inhibiting production of multiple mediators of cartilage destruction. PMID:15843581

MSX2 stimulates chondrocyte maturation by controlling Ihh expression.

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Amano, Katsuhiko; Ichida, Fumitaka; Sugita, Atsushi; Hata, Kenji; Wada, Masahiro; Takigawa, Yoko; Nakanishi, Masako; Kogo, Mikihiko; Nishimura, Riko; Yoneda, Toshiyuki

2008-10-24

Several studies indicated that a homeobox gene, Msx2, is implicated in regulation of skeletal development by controlling enchondral ossification as well as membranous ossification. However, the molecular basis by which Msx2 conducts chondrogenesis is currently unclear. In this study, we examined the role of Msx2 in chondrocyte differentiation using mouse primary chondrocytes and embryonic metatarsal explants. Treatment with BMP2 up-regulated the expression of Msx2 mRNA along with chondrocyte differentiation in murine primary chondrocytes. Overexpression of wild-type Msx2 stimulated calcification of primary chondrocytes in the presence of BMP2. We also found that constitutively active Msx2 (caMsx2) enhanced BMP2-dependent calcification more efficiently than wild-type Msx2. Consistently, caMsx2 overexpression up-regulated the expression of alkaline phosphatase and collagen type X induced by BMP2. Furthermore, organ culture experiments using mouse embryonic metatarsals indicated that caMsx2 clearly stimulated the maturation of chondrocytes into the prehypertrophic and hypertrophic stages in the presence of BMP2. In contrast, knockdown of Msx2 inhibited maturation of primary chondrocytes. The stimulatory effect of Msx2 on chondrocyte maturation was enhanced by overexpression of Smad1 and Smad4 but inhibited by Smad6, an inhibitory Smad for BMP2 signaling. These data suggest that Msx2 requires BMP2/Smad signaling for its chondrogenic action. In addition, caMsx2 overexpression induced Ihh (Indian hedgehog) expression in mouse primary chondrocytes. Importantly, treatment with cyclopamine, a specific inhibitor for hedgehogs, blocked Msx2-induced chondrogenesis. Collectively, our results indicated that Msx2 promotes the maturation of chondrocytes, at least in part, through up-regulating Ihh expression.

Study on human chondrocyte culture viability for autologous transplantation in clinical application

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Christiane Lombello

2003-06-01

Full Text Available Objective: The limited regenerative capacity of the cartilage tissuemakes the treatment of chondral lesions difficult. The techniquescurrently available to treat cartilage lesions may relieve symptoms,but do not regenerate the injured tissue. Autologous chondrocytetransplantation uses cell biology and cell culture techniques toregenerate the hyaline cartilage. Methods: In this study, we analyzechondrocyte biopsy collection and culture for autologoustransplantation. Ultrastructural analyses of hyaline cartilage biopsieswere performed 0, 6, 24 and 48 hours after collection. The tissue evenafter 48 hours. Eleven cell culture assays were performed to evaluateisolation, viability, morphology, proliferation and absence ofcontaminants. Results: The cell culture techniques used allowedchondrocyte proliferation. Rates on cell viability were maintained abovethe acceptable patterns (above 90. Control of cell culture laboratoryconditions showed absence of contaminants, assuring safety of theprocess. The chondrocytes obtained presented the morphology typicalof cultured cell monolayers. Conclusion: The results indicate viabilityof chondrocyte culture technique for clinical application in autologoustransplantation.

Proteoglycon synthesis by articular chondrocytes in agarose culture

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Sweet, M.B.E.; Grisillo, A.; Coehlo, A.; Schnitzler, C.M.

1987-01-01

Articular chondrocytes were isolated from knee joints of full-term bovine foetuses and grown in long-term agarose cultures. At intervals, cultures were labelled with 35 S-[sulphate] or D[6- 3 H] glucosamine. Newly synthesized proteoglycans were extracted with 4 M guanidine HCl and purified by isopycnic density gradient centrifugation or on DEAE cellulose in the presence of 8 M urea. Characterization of the proteoglycans revealed them to be identical in size to those present in the tissue and to be similarly capable of aggregation with hyaluronate. Newly synthesized chondroitin sulphate chains were identical in size, but newly synthesized keratan sulphate chains were somewhat larger than those present in the tissue. The newly synthesized proteoglycans were shown to contain the same range of O-linked oligosaccharides identified in proteoglycans of the Swarm rat chondrosarcoma. Cartilage-specific proteoglycan continued to be synthesized by the chondrocytes for up to 60 days; however, with time, proportionately more of a small non-aggregating proteoglycan appeared

Importance of Donor Chondrocyte Viability for Osteochondral Allografts.

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Cook, James L; Stannard, James P; Stoker, Aaron M; Bozynski, Chantelle C; Kuroki, Keiichi; Cook, Cristi R; Pfeiffer, Ferris M

2016-05-01

Osteochondral allograft (OCA) transplantation provides a biological treatment option for functional restoration of large articular cartilage defects in multiple joints. While successful outcomes after OCA transplantation have been linked to viable donor chondrocytes, the importance of donor cell viability has not been comprehensively validated. To use a canine model to determine the importance of donor chondrocyte viability at the time of implantation with respect to functional success of femoral condylar OCAs based on radiographic, gross, cell viability, histologic, biochemical, and biomechanical outcome measures. Controlled laboratory study. After approval was obtained from the institutional animal care and use committee, adult female dogs (N = 16) were implanted with 8-mm cylindrical OCAs from male dogs in the lateral and medial femoral condyles of 1 knee. OCAs were preserved for 28 or 60 days after procurement, and chondrocyte viability was quantified before implantation. Two different storage media, temperatures, and time points were used to obtain a spectrum of percentage chondrocyte viability at the time of implantation. A successful outcome was defined as an OCA that was associated with graft integration, maintenance of hyaline cartilage, lack of associated cartilage disorder, and lack of fibrillation, fissuring, or fibrous tissue infiltration of the allograft based on subjective radiographic, gross, and histologic assessments at 6 months after implantation. Chondrocyte viability ranged from 23% to 99% at the time of implantation. All successful grafts had >70% chondrocyte viability at the time of implantation, and no graft with chondrocyte viability <70% was associated with a successful outcome. Live-dead stained sections and histologic findings with respect to cell morphological features suggested that successful grafts were consistently composed of viable chondrocytes in lacunae, while grafts that were not successful were composed of nonviable

Regulative mechanisms of chondrocyte adhesion

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Schmal, Hagen; Mehlhorn, Alexander T; Fehrenbach, Miriam

2006-01-01

Interaction between chondrocytes and extracellular matrix is considered a key factor in the generation of grafts for matrix-associated chondrocyte transplantation. Therefore, our objective was to study the influence of differentiation status on cellular attachment. Adhesion of chondrocytes...... to collagen type II increased after removal from native cartilage up to the third day in monolayer in a dose-dependent manner. Following dedifferentiation after the second passage, adhesion to collagen types I (-84%) and II (-46%) decreased, whereas adhesion to fibrinogen (+59%) and fibronectin (+43......%) increased. A cartilage construct was developed based on a clinically established collagen type I scaffold. In this matrix, more than 80% of the cells could be immobilized by mechanisms of adhesion, filtration, and cell entrapment. Confocal laser microscopy revealed focal adhesion sites as points of cell...

Sprifermin (rhFGF18) enables proliferation of chondrocytes producing a hyaline cartilage matrix.

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Gigout, A; Guehring, H; Froemel, D; Meurer, A; Ladel, C; Reker, D; Bay-Jensen, A C; Karsdal, M A; Lindemann, S

2017-11-01

Fibroblast growth factor (FGF) 18 has been shown to increase cartilage volume when injected intra-articularly in animal models of osteoarthritis (OA) and in patients with knee OA (during clinical development of the recombinant human FGF18, sprifermin). However, the exact nature of this effect is still unknown. In this study, we aimed to investigate the effects of sprifermin at the cellular level. A combination of different chondrocyte culture systems was used and the effects of sprifermin on proliferation, the phenotype and matrix production were evaluated. The involvement of MAPKs in sprifermin signalling was also studied. In monolayer, we observed that sprifermin promoted a round cell morphology and stimulated both cellular proliferation and Sox9 expression while strongly decreasing type I collagen expression. In 3D culture, sprifermin increased the number of matrix-producing chondrocytes, improved the type II:I collagen ratio and enabled human OA chondrocytes to produce a hyaline extracellular matrix (ECM). Furthermore, we found that sprifermin displayed a 'hit and run' mode of action, with intermittent exposure required for the compound to fully exert its anabolic effect. Finally, sprifermin appeared to signal through activation of ERK. Our results indicate that intermittent exposure to sprifermin leads to expansion of hyaline cartilage-producing chondrocytes. These in vitro findings are consistent with the increased cartilage volume observed in the knees of OA patients after intra-articular injection with sprifermin in clinical studies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mesenchymal stem cell-derived extracellular matrix enhances chondrogenic phenotype of and cartilage formation by encapsulated chondrocytes in vitro and in vivo.

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Yang, Yuanheng; Lin, Hang; Shen, He; Wang, Bing; Lei, Guanghua; Tuan, Rocky S

2018-03-15

Mesenchymal stem cell derived extracellular matrix (MSC-ECM) is a natural biomaterial with robust bioactivity and good biocompatibility, and has been studied as a scaffold for tissue engineering. In this investigation, we tested the applicability of using decellularized human bone marrow derived MSC-ECM (hBMSC-ECM) as a culture substrate for chondrocyte expansion in vitro, as well as a scaffold for chondrocyte-based cartilage repair. hBMSC-ECM deposited by hBMSCs cultured on tissue culture plastic (TCP) was harvested, and then subjected to a decellularization process to remove hBMSCs. Compared with chondrocytes grown on TCP, chondrocytes seeded onto hBMSC-ECM exhibited significantly increased proliferation rate, and maintained better chondrocytic phenotype than TCP group. After being expanded to the same cell number and placed in high-density micromass cultures, chondrocytes from the ECM group showed better chondrogenic differentiation profile than those from the TCP group. To test cartilage formation ability, composites of hBMSC-ECM impregnated with chondrocytes were subjected to brief trypsin treatment to allow cell-mediated contraction, and folded to form 3-dimensional chondrocyte-impregnated hBMSC-ECM (Cell/ECM constructs). Upon culture in vitro in chondrogenic medium for 21 days, robust cartilage formation was observed in the Cell/ECM constructs. Similarly prepared Cell/ECM constructs were tested in vivo by subcutaneous implantation into SCID mice. Prominent cartilage formation was observed in the implanted Cell/ECM constructs 14 days post-implantation, with higher sGAG deposition compared to controls consisting of chondrocyte cell sheets. Taken together, these findings demonstrate that hBMSC-ECM is a superior culture substrate for chondrocyte expansion and a bioactive matrix potentially applicable for cartilage regeneration in vivo. Current cell-based treatments for focal cartilage defects face challenges, including chondrocyte dedifferentiation, need for

Silencing of microRNA-138-5p promotes IL-1β-induced cartilage degradation in human chondrocytes by targeting FOXC1: miR-138 promotes cartilage degradation.

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Yuan, Y; Zhang, G Q; Chai, W; Ni, M; Xu, C; Chen, J Y

2016-10-01

Osteoarthritis (OA) is characterised by articular cartilage degradation. MicroRNAs (miRNAs) have been identified in the development of OA. The purpose of our study was to explore the functional role and underlying mechanism of miR-138-5p in interleukin-1 beta (IL-1β)-induced extracellular matrix (ECM) degradation of OA cartilage. Human articular cartilage was obtained from patients with and without OA, and chondrocytes were isolated and stimulated by IL-1β. The expression levels of miR-138-5p in cartilage and chondrocytes were both determined. After transfection with miR-138-5p mimics, allele-specific oligonucleotide (ASO)-miR-138-5p, or their negative controls, the messenger RNA (mRNA) levels of aggrecan (ACAN), collagen type II and alpha 1 (COL2A1), the protein levels of glycosaminoglycans (GAGs), and both the mRNA and protein levels of matrix metalloproteinase (MMP)-13 were evaluated. Luciferase reporter assay, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot were performed to explore whether Forkhead Box C1 (FOCX1) was a target of miR-138-5p. Further, we co-transfected OA chondrocytes with miR-138-5p mimics and pcDNA3.1 (+)-FOXC1 and then stimulated with IL-1β to determine whether miR-138-5p-mediated IL-1β-induced cartilage matrix degradation resulted from targeting FOXC1. MiR-138-5p was significantly increased in OA cartilage and in chondrocytes in response to IL-1β-stimulation. Overexpression of miR-138-5p significantly increased the IL-1β-induced downregulation of COL2A1, ACAN, and GAGs, and increased the IL-1β-induced over expression of MMP-13.We found that FOXC1 is directly regulated by miR-138-5p. Additionally, co-transfection with miR-138-5p mimics and pcDNA3.1 (+)-FOXC1 resulted in higher levels of COL2A1, ACAN, and GAGs, but lower levels of MMP-13. miR-138-5p promotes IL-1β-induced cartilage degradation in human chondrocytes, possibly by targeting FOXC1.Cite this article: Y. Yuan, G. Q. Zhang, W. Chai,M. Ni, C. Xu, J

Regulation of collagenase inhibitor production in chondrosarcoma chondrocytes

International Nuclear Information System (INIS)

Harper, J.; Harper, E.

1987-01-01

Swarm rat chondrosarcoma chondrocytes produce an inhibitor of collagenase. This inhibitor is similar to those isolated from normal cartilage tissues. These cells will synthesize proteins in the absence of serum. Since serum contains inhibitors of collagenase, it is necessary to culture cells without serum in order to obtain accurate measurements of enzyme and inhibitor levels. They examined the effect of insulin on inhibitor secretion by cultures of Swarm rat chondrosarcoma chondrocytes. They observed a 2.5 to 3.5 fold stimulation of inhibitory activity in the presence of as little as 10 ng/ml insulin as compared to controls in serum free Dulbecco's modified Eagle's medium supplemented with 4.5 g/l glucose. The units of inhibitor were determined over a 7 day culture period. Medium was harvested daily and assayed for collagenase activity and for inhibition of a known collagenase from rabbit skin or human skin, using the 14 C-glycine peptide release assay. The amount of inhibitor obtained from days 2 through 7 were: 1.4 unit (control), 3.8 units (10 ng/ml insulin), 5.2 units (1 μg/ml insulin). The addition of 1 mM dibutyryl cyclic AMP to these chondrocytes in the presence of 1 μg/ml insulin caused a decrease in the level of inhibitor, suggesting that a dephosphorylation event may be necessary for this stimulation by insulin to occur

Biomarkers of Chondrocyte Apoptosis and Autophagy in Osteoarthritis

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Musumeci, Giuseppe; Castrogiovanni, Paola; Trovato, Francesca Maria; Weinberg, Annelie Martina; Al-Wasiyah, Mohammad K.; Alqahtani, Mohammed H.; Mobasheri, Ali

2015-01-01

Cell death with morphological and molecular features of apoptosis has been detected in osteoarthritic (OA) cartilage, which suggests a key role for chondrocyte death/survival in the pathogenesis of OA. Identification of biomarkers of chondrocyte apoptosis may facilitate the development of novel therapies that may eliminate the cause or, at least, slow down the degenerative processes in OA. The aim of this review was to explore the molecular markers and signals that induce chondrocyte apoptosis in OA. A literature search was conducted in PubMed, Scopus, Web of Science and Google Scholar using the keywords chondrocyte death, apoptosis, osteoarthritis, autophagy and biomarker. Several molecules considered to be markers of chondrocyte apoptosis will be discussed in this brief review. Molecular markers and signalling pathways associated with chondroycte apoptosis may turn out to be therapeutic targets in OA and approaches aimed at neutralizing apoptosis-inducing molecules may at least delay the progression of cartilage degeneration in OA. PMID:26334269

The inhibitory roles of Ihh downregulation on chondrocyte growth and differentiation.

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Deng, Ang; Zhang, Hongqi; Hu, Minyu; Liu, Shaohua; Wang, Yuxiang; Gao, Qile; Guo, Chaofeng

2018-01-01

The proliferative rate of chondrocytes affects bone elongation. Chondrocyte hypertrophy is required for endochondral bone formation as chondrocytes secrete factors required for osteoblast differentiation and maturation. Previous studies have demonstrated that the Indian hedgehog (Ihh) signaling pathway is a key regulator of skeletal development and homeostasis. The aim of the present study was to investigate the function of Ihh in chondrocyte proliferation and differentiation, as well as the underlying mechanisms. Ihh was knocked down in mouse chondrocyte cells using short hairpin RNA. Chondrocyte apoptosis and cell cycle arrest were assessed using flow cytometry and the results indicated that knockdown of Ihh significantly inhibited cell growth (PIhh also resulted in cell cycle arrest at G1 to S phase in chondrocytes. It was also observed that knockdown of Ihh decreased alkaline phosphatase activity and mineral deposition of chondrocytes. The inhibitory roles of Ihh downregulation on chondrocyte growth and differentiation may be associated with the transforming growth factor-β/mothers against decapentaplegic and osteoprotegerin/receptor activator of nuclear factor κB ligand signaling pathway. The results of the present study suggest that chondrocyte-derived Ihh is essential for maintaining bone growth plates and that manipulation of Ihh expression or its signaling components may be a novel therapeutic technique for the treatment of skeletal diseases, including achondroplasia.

Tissue engineering applications: cartilage lesions repair by the use of autologous chondrocytes

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L. De Franceschi

2011-09-01

Full Text Available Promising new therapies based on tissue engineering have been recently developed for cartilage repair. The association of biomaterials with autologous chondrocytes expanded in vitro can represent a useful tool to regenerate this tissue. The scaffolds utilised in such therapeutical applications should provide a pre-formed three-dimensional shape, prevent cells from floating out of the defect, have sufficient mechanical strength, facilitate uniform spread of cells and stimulate the phenotype of transplanted cells. Hyaff®-11 is a hyaluronic-acid based biodegradable polymer, that has been shown to provide successful cell carrier for tissue-engineered repair. From our findings we can state that human chondrocytes seeded on Hyaff®-11 are able to maintain in vitro the characteristic of differentiated cells, expressing and producing collagen type II and aggrecan which are the main markers of cartilage phenotype, down-regulating collagen type I. Moreover, it seems to be a useful scaffold for cartilage repair both in animal models and clinical trials in humans, favouring the formation of a hyaline-like tissue. In the light of these data, we can hypothesise, for the future, the use of autologous chondrocyte transplantation together with gene therapy as a treatment for rheumatic diseases such as osteoarthritis.

Constitutive activation of MEK1 in chondrocytes causes Stat1-independent achondroplasia-like dwarfism and rescues the Fgfr3-deficient mouse phenotype

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Murakami, Shunichi; Balmes, Gener; McKinney, Sandra; Zhang, Zhaoping; Givol, David; de Crombrugghe, Benoit

2004-01-01

We generated transgenic mice that express a constitutively active mutant of MEK1 in chondrocytes. These mice showed a dwarf phenotype similar to achondroplasia, the most common human dwarfism, caused by activating mutations in FGFR3. These mice displayed incomplete hypertrophy of chondrocytes in the growth plates and a general delay in endochondral ossification, whereas chondrocyte proliferation was unaffected. Immunohistochemical analysis of the cranial base in transgenic embryos showed reduced staining for collagen type X and persistent expression of Sox9 in chondrocytes. These observations indicate that the MAPK pathway inhibits hypertrophic differentiation of chondrocytes and negatively regulates bone growth without inhibiting chondrocyte proliferation. Expression of a constitutively active mutant of MEK1 in chondrocytes of Fgfr3-deficient mice inhibited skeletal overgrowth, strongly suggesting that regulation of bone growth by FGFR3 is mediated at least in part by the MAPK pathway. Although loss of Stat1 restored the reduced chondrocyte proliferation in mice expressing an achondroplasia mutant of Fgfr3, it did not rescue the reduced hypertrophic zone, the delay in formation of secondary ossification centers, and the achondroplasia-like phenotype. These observations suggest a model in which Fgfr3 signaling inhibits bone growth by inhibiting chondrocyte differentiation through the MAPK pathway and by inhibiting chondrocyte proliferation through Stat1. PMID:14871928

Sphingosine-1-phosphate stimulates rat primary chondrocyte proliferation

International Nuclear Information System (INIS)

Kim, Mi-Kyoung; Lee, Ha Young; Kwak, Jong-Young; Park, Joo-In; Yun, Jeanho; Bae, Yoe-Sik

2006-01-01

Rat primary chondrocytes express the sphingosine-1-phosphate (S1P) receptor, S1P 2 , S1P 3 , S1P 4 , but not S1P 1 . When chondrocytes were stimulated with S1P or phytosphingosine-1-phosphate (PhS1P, an S1P 1 - and S1P 4 -selective agonist), phospholipase C-mediated cytosolic calcium increase was dramatically induced. S1P and PhS1P also stimulated two kinds of mitogen-activated protein kinases, extracellular signal-regulated kinase (ERK) and p38 kinase in chondrocytes. In terms of the two phospholipids-mediated functional modulation of chondrocytes, S1P and PhS1P stimulated cellular proliferation. The two phospholipids-induced chondrocyte proliferations were almost completely blocked by PD98059 but not by SB203580, suggesting that ERK but not p38 kinase is essentially required for the proliferation. Pertussis toxin almost completely inhibited the two phospholipids-induced cellular proliferation and ERK activation, indicating the crucial role of G i protein. This study demonstrates the physiological role of two important phospholipids (S1P and PhS1P) on the modulation of rat primary chondrocyte proliferation, and the crucial role played by ERK in the process

TGF-β1, GDF-5, and BMP-2 stimulation induces chondrogenesis in expanded human articular chondrocytes and marrow-derived stromal cells.

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Murphy, Meghan K; Huey, Daniel J; Hu, Jerry C; Athanasiou, Kyriacos A

2015-03-01

Replacement of degenerated cartilage with cell-based cartilage products may offer a long-term solution to halt arthritis' degenerative progression. Chondrocytes are frequently used in cell-based FDA-approved cartilage products; yet human marrow-derived stromal cells (hMSCs) show significant translational potential, reducing donor site morbidity and maintaining their undifferentiated phenotype with expansion. This study sought to investigate the effects of transforming growth factor β1 (TGF-β1), growth/differentiation factor 5 (GDF-5), and bone morphogenetic protein 2 (BMP-2) during postexpansion chondrogenesis in human articular chondrocytes (hACs) and to compare chondrogenesis in passaged hACs with that of passaged hMSCs. Through serial expansion, chondrocytes dedifferentiated, decreasing expression of chondrogenic genes while increasing expression of fibroblastic genes. However, following expansion, 10 ng/mL TGF-β1, 100 ng/mL GDF-5, or 100 ng/mL BMP-2 supplementation during three-dimensional aggregate culture each upregulated one or more markers of chondrogenic gene expression in both hACs and hMSCs. Additionally, in both cell types, the combination of TGF-β1, GDF-5, and BMP-2 induced the greatest upregulation of chondrogenic genes, that is, Col2A1, Col2A1/Col1A1 ratio, SOX9, and ACAN, and synthesis of cartilage-specific matrix, that is, glycosaminoglycans (GAGs) and ratio of collagen II/I. Finally, TGF-β1, GDF-5, and BMP-2 stimulation yielded mechanically robust cartilage rich in collagen II and GAGs in both cell types, following 4 weeks maturation. This study illustrates notable success in using the self-assembling method to generate robust, scaffold-free neocartilage constructs using expanded hACs and hMSCs. © 2014 AlphaMed Press.

Elastic cartilage reconstruction by transplantation of cultured hyaline cartilage-derived chondrocytes.

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Mizuno, M; Takebe, T; Kobayashi, S; Kimura, S; Masutani, M; Lee, S; Jo, Y H; Lee, J I; Taniguchi, H

2014-05-01

Current surgical intervention of craniofacial defects caused by injuries or abnormalities uses reconstructive materials, such as autologous cartilage grafts. Transplantation of autologous tissues, however, places a significant invasiveness on patients, and many efforts have been made for establishing an alternative graft. Recently, we and others have shown the potential use of reconstructed elastic cartilage from ear-derived chondrocytes or progenitors with the unique elastic properties. Here, we examined the differentiation potential of canine joint cartilage-derived chondrocytes into elastic cartilage for expanding the cell sources, such as hyaline cartilage. Articular chondrocytes are isolated from canine joint, cultivated, and compared regarding characteristic differences with auricular chondrocytes, including proliferation rates, gene expression, extracellular matrix production, and cartilage reconstruction capability after transplantation. Canine articular chondrocytes proliferated less robustly than auricular chondrocytes, but there was no significant difference in the amount of sulfated glycosaminoglycan produced from redifferentiated chondrocytes. Furthermore, in vitro expanded and redifferentiated articular chondrocytes have been shown to reconstruct elastic cartilage on transplantation that has histologic characteristics distinct from hyaline cartilage. Taken together, cultured hyaline cartilage-derived chondrocytes are a possible cell source for elastic cartilage reconstruction. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is increased in osteoarthritis and regulates chondrocyte catabolic and anabolic activities

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Long, D.L.; Ulici, V.; Chubinskaya, S.; Loeser, R.F.

2015-01-01

Objective We determined if the epidermal growth factor receptor ligand HB-EGF is produced in cartilage and if it regulates chondrocyte anabolic or catabolic activity. Methods HB-EGF expression was measured by quantitative PCR using RNA isolated from mouse knee joint tissues and from normal and OA human chondrocytes. Immunohistochemistry was performed on normal and OA human cartilage and meniscus sections. Cultured chondrocytes were treated with fibronectin fragments (FN-f) as a catabolic stimulus and osteogenic protein 1 (OP-1) as an anabolic stimulus. Effects of HB-EGF on cell signaling were analyzed by immunoblotting of selected signaling proteins. MMP-13 was measured in conditioned media, proteoglycan synthesis was measured by sulfate incorporation, and matrix gene expression by quantitative PCR. Results HB-EGF expression was increased in 12-month old mice at 8 weeks after surgery to induce OA and increased amounts of HB-EGF were noted in human articular cartilage from OA knees. FN-f stimulated chondrocyte HB-EGF expression and HB-EGF stimulated chondrocyte MMP-13 production. However, HB-EGF was not required for FN-f stimulation of MMP-13 production. HB-EGF activated the ERK and p38 MAP kinases and stimulated phosphorylation of Smad1 at an inhibitory serine site which was associated with inhibition of OP-1 mediated proteoglycan synthesis and reduced aggrecan (ACAN) but not COL2A1 expression. Conclusion HB-EGF is a new factor identified in OA cartilage that promotes chondrocyte catabolic activity while inhibiting anabolic activity suggesting it could contribute to the catabolic-anabolic imbalance seen in OA cartilage. PMID:25937027

Transforming growth factor-beta predominantly stimulates phenotypically changed chondrocytes in osteoarthritic human cartilage

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Lafeber, F. P.; van Roy, H. L.; van der Kraan, P. M.; van den Berg, W. B.; Bijlsma, J. W.

1997-01-01

One of the most prominent alterations that characterizes osteoarthritic cartilage damage is a reduction of proteoglycan content, reflecting an imbalance between synthesis and release of proteoglycans. Both synthesis and release depend on the activity of cartilage cells. Chondrocytes in the upper

Na⁺, K⁺-ATPase Subunit Composition in a Human Chondrocyte Cell Line; Evidence for the Presence of α1, α3, β1, β2 and β3 Isoforms

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Ali Mobasheri

2012-04-01

Full Text Available Membrane transport systems participate in fundamental activities such as cell cycle control, proliferation, survival, volume regulation, pH maintenance and regulation of extracellular matrix synthesis. Multiple isoforms of Na⁺, K⁺-ATPase are expressed in primary chondrocytes. Some of these isoforms have previously been reported to be expressed exclusively in electrically excitable cells (i.e., cardiomyocytes and neurons. Studying the distribution of Na⁺, K⁺-ATPase isoforms in chondrocytes makes it possible to document the diversity of isozyme pairing and to clarify issues concerning Na⁺, K⁺-ATPase isoform abundance and the physiological relevance of their expression. In this study, we investigated the expression of Na⁺, K⁺-ATPase in a human chondrocyte cell line (C-20/A4 using a combination of immunological and biochemical techniques. A panel of well-characterized antibodies revealed abundant expression of the α1, β1 and β2 isoforms. Western blot analysis of plasma membranes confirmed the above findings. Na⁺, K⁺-ATPase consists of multiple isozyme variants that endow chondrocytes with additional homeostatic control capabilities. In terms of Na⁺, K⁺-ATPase expression, the C-20/A4 cell line is phenotypically similar to primary and in situ chondrocytes. However, unlike freshly isolated chondrocytes, C-20/A4 cells are an easily accessible and convenient in vitro model for the study of Na⁺, K⁺-ATPase expression and regulation in chondrocytes.

Downregulation of protein kinase CK2 activity facilitates tumor necrosis factor-α-mediated chondrocyte death through apoptosis and autophagy.

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Sung Won Lee

Full Text Available Despite the numerous studies of protein kinase CK2, little progress has been made in understanding its function in chondrocyte death. Our previous study first demonstrated that CK2 is involved in apoptosis of rat articular chondrocytes. Recent studies have suggested that CK2 downregulation is associated with aging. Thus examining the involvement of CK2 downregulation in chondrocyte death is an urgently required task. We undertook this study to examine whether CK2 downregulation modulates chondrocyte death. We first measured CK2 activity in articular chondrocytes of 6-, 21- and 30-month-old rats. Noticeably, CK2 activity was downregulated in chondrocytes with advancing age. To build an in vitro experimental system for simulating tumor necrosis factor (TNF-α-induced cell death in aged chondrocytes with decreased CK2 activity, chondrocytes were co-treated with CK2 inhibitors and TNF-α. Viability assay demonstrated that CK2 inhibitors facilitated TNF-α-mediated chondrocyte death. Pulsed-field gel electrophoresis, nuclear staining, flow cytometry, TUNEL staining, confocal microscopy, western blot and transmission electron microscopy were conducted to assess cell death modes. The results of multiple assays showed that this cell death was mediated by apoptosis. Importantly, autophagy was also involved in this process, as supported by the appearance of a punctuate LC3 pattern and autophagic vacuoles. The inhibition of autophagy by silencing of autophage-related genes 5 and 7 as well as by 3-methyladenine treatment protected chondrocytes against cell death and caspase activation, indicating that autophagy led to the induction of apoptosis. Autophagic cells were observed in cartilage obtained from osteoarthritis (OA model rats and human OA patients. Our findings indicate that CK2 down regulation facilitates TNF-α-mediated chondrocyte death through apoptosis and autophagy. It should be clarified in the future if autophagy observed is a consequence

Multi-membrane chitosan hydrogels as chondrocytic cell bioreactors.

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Ladet, S G; Tahiri, K; Montembault, A S; Domard, A J; Corvol, M-T M

2011-08-01

We investigated the bioactivity of new chitosan-based multi-membrane hydrogel (MMH) architectures towards chondrocyte-like cells. The microstructure of the hydrogels constituting the membranes precludes any living cell penetration, whereas their lower scale architecture allows the protein diffusion. The biological behavior of chondrocytes implanted within the MMH inter-membrane spaces was studied for 45 days in culture. Chondrocytes formed cell aggregates and proliferated without loosing their chondrogenic phenotype as illustrated by collagen II and aggrecan expressions at the mRNA and protein levels. Cells produced neo-formed alcyan blue matrix proteins filling MMH interspaces. The HiF-2α/SOX9 pattern of expression suggested that the elevated chondrocytic phenotype in MMH could be related to a better hypoxic local environment than in classical culture conditions. Pro-inflammatory markers were not expressed during the period of culture. The low level of nitric oxide accumulation within the inter-membrane spaces and in the incubation medium implied that chitosan consumed nitrites produced by entrapped chondrocytes, in relation with the decrease of its molecular weight of 50%. Our data suggest that MMH structures may be considered as complex chondrocytic cell bioreactors; "active decoys of biological media", potentially promising for various biomedical applications like the inter-vertebral disk replacement. Copyright © 2011 Elsevier Ltd. All rights reserved.

Micromass co-culture of human articular chondrocytes and human bone marrow mesenchymal stem cells to investigate stable neocartilage tissue formation in vitro

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S Giovannini

2010-10-01

Full Text Available Cell therapies for articular cartilage defects rely on expanded chondrocytes. Mesenchymal stem cells (MSC represent an alternative cell source should their hypertrophic differentiation pathway be prevented. Possible cellular instruction between human articular chondrocytes (HAC and human bone marrow MSC was investigated in micromass pellets. HAC and MSC were mixed in different percentages or incubated individually in pellets for 3 or 6 weeks with and without TGF-beta1 and dexamethasone (±T±D as chondrogenic factors. Collagen II, collagen X and S100 protein expression were assessed using immunohistochemistry. Proteoglycan synthesis was evaluated applying the Bern score and quantified using dimethylmethylene blue dye binding assay. Alkaline phosphatase activity (ALP was detected on cryosections and soluble ALP measured in pellet supernatants. HAC alone generated hyaline-like discs, while MSC formed spheroid pellets in ±T±D. Co-cultured pellets changed from disc to spheroid shape with decreasing number of HAC, and displayed random cell distribution. In -T-D, HAC expressed S100, produced GAG and collagen II, and formed lacunae, while MSC did not produce any cartilage-specific proteins. Based on GAG, collagen type II and S100 expression chondrogenic differentiation occurred in -T-D MSC co-cultures. However, quantitative experimental GAG and DNA values did not differ from predicted values, suggesting only HAC contribution to GAG production. MSC produced cartilage-specific matrix only in +T+D but underwent hypertrophy in all pellet cultures. In summary, influence of HAC on MSC was restricted to early signs of neochondrogenesis. However, MSC did not contribute to the proteoglycan deposition, and HAC could not prevent hypertrophy of MSC induced by chondrogenic stimuli.

Viability of chondrocytes seeded onto a collagen I/III membrane for matrix-induced autologous chondrocyte implantation.

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Hindle, Paul; Hall, Andrew C; Biant, Leela C

2014-11-01

Cell viability is crucial for effective cell-based cartilage repair. The aim of this study was to determine the effect of handling the membrane during matrix-induced autologous chondrocyte implantation surgery on the viability of implanted chondrocytes. Images were acquired under five conditions: (i) Pre-operative; (ii) Handled during surgery; (iii) Cut edge; (iv) Thumb pressure applied; (v) Heavily grasped with forceps. Live and dead cell stains were used. Images were obtained for cell counting and morphology. Mean cell density was 6.60 × 10(5) cells/cm(2) (5.74-7.11 × 10(5) ) in specimens that did not have significant trauma decreasing significantly in specimens that had been grasped with forceps (p < 0.001) or cut (p = 0.004). Cell viability on delivery grade membrane was 75.1%(72.4-77.8%). This dropped to 67.4%(64.1-69.7%) after handling (p = 0.002), 56.3%(51.5-61.6%) after being thumbed (p < 0.001) and 28.8%(24.7-31.2%) after crushing with forceps (p < 0.001). When cut with scissors there was a band of cell death approximately 275 µm in width where cell viability decreased to 13.7%(10.2-18.2%, p < 0.001). Higher magnification revealed cells without the typical rounded appearance of chondrocytes. We found that confocal laser-scanning microscope (CLSM) can be used to quantify and image the fine morphology of cells on a matrix-induced autologous chondrocyte implantation (MACI) membrane. Careful handling of the membrane is essential to minimise chondrocyte death during surgery. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

The properties of bioengineered chondrocyte sheets for cartilage regeneration

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Ota Naoshi

2009-03-01

Full Text Available Abstract Background Although the clinical results of autologous chondrocyte implantation for articular cartilage defects have recently improved as a result of advanced techniques based on tissue engineering procedures, problems with cell handling and scaffold imperfections remain to be solved. A new cell-sheet technique has been developed, and is potentially able to overcome these obstacles. Chondrocyte sheets applicable to cartilage regeneration can be prepared with this cell-sheet technique using temperature-responsive culture dishes. However, for clinical application, it is necessary to evaluate the characteristics of the cells in these sheets and to identify their similarities to naive cartilage. Results The expression of SOX 9, collagen type 2, 27, integrin α10, and fibronectin genes in triple-layered chondrocyte sheets was significantly increased in comparison to those in conventional monolayer culture and in a single chondrocyte sheet, implying a nature similar to ordinary cartilage. In addition, immunohistochemistry demonstrated that collagen type II, fibronectin, and integrin α10 were present in the triple-layered chondrocyte sheets. Conclusion The results of this study indicate that these chondrocyte sheets with a consistent cartilaginous phenotype and adhesive properties may lead to a new strategy for cartilage regeneration.

Deciphering chondrocyte behaviour in matrix-induced autologous chondrocyte implantation to undergo accurate cartilage repair with hyaline matrix.

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Demoor, M; Maneix, L; Ollitrault, D; Legendre, F; Duval, E; Claus, S; Mallein-Gerin, F; Moslemi, S; Boumediene, K; Galera, P

2012-06-01

Since the emergence in the 1990s of the autologous chondrocytes transplantation (ACT) in the treatment of cartilage defects, the technique, corresponding initially to implantation of chondrocytes, previously isolated and amplified in vitro, under a periosteal membrane, has greatly evolved. Indeed, the first generations of ACT showed their limits, with in particular the dedifferentiation of chondrocytes during the monolayer culture, inducing the synthesis of fibroblastic collagens, notably type I collagen to the detriment of type II collagen. Beyond the clinical aspect with its encouraging results, new biological substitutes must be tested to obtain a hyaline neocartilage. Therefore, the use of differentiated chondrocytes phenotypically stabilized is essential for the success of ACT at medium and long-term. That is why researchers try now to develop more reliable culture techniques, using among others, new types of biomaterials and molecules known for their chondrogenic activity, giving rise to the 4th generation of ACT. Other sources of cells, being able to follow chondrogenesis program, are also studied. The success of the cartilage regenerative medicine is based on the phenotypic status of the chondrocyte and on one of its essential component of the cartilage, type II collagen, the expression of which should be supported without induction of type I collagen. The knowledge accumulated by the scientific community and the experience of the clinicians will certainly allow to relief this technological challenge, which influence besides, the validation of such biological substitutes by the sanitary authorities. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Curcumin Inhibits Apoptosis of Chondrocytes through Activation ERK1/2 Signaling Pathways Induced Autophagy

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Xiaodong Li

2017-04-01

Full Text Available Osteoarthritis (OA is an inflammatory disease of load-bearing synovial joints that is currently treated with drugs that exhibit numerous side effects and are only temporarily effective in treating pain, the main symptom of the disease. Consequently, there is an acute need for novel, safe, and more effective chemotherapeutic agents for the treatment of osteoarthritis and related arthritic diseases. Curcumin, the principal curcuminoid and the most active component in turmeric, is a biologically active phytochemical. Evidence from several recent in vitro studies suggests that curcumin may exert a chondroprotective effect through actions such as anti-inflammatory, anti-oxidative stress, and anti-catabolic activity that are critical for mitigating OA disease pathogenesis and symptoms. In the present study, we investigated the protective mechanisms of curcumin on interleukin 1β (IL-1β-stimulated primary chondrocytes in vitro. The treatment of interleukin (IL-1β significantly reduces the cell viability of chondrocytes in dose and time dependent manners. Co-treatment of curcumin with IL-1β significantly decreased the growth inhibition. We observed that curcumin inhibited IL-1β-induced apoptosis and caspase-3 activation in chondrocytes. Curcumin can increase the expression of phosphorylated extracellular signal-regulated kinases 1/2 (ERK1/2, autophagy marker light chain 3 (LC3-II, and Beclin-1 in chondrocytes. The expression of autophagy markers could be decreased when the chondrocytes were incubated with ERK1/2 inhibitor U0126. Our results suggest that curcumin suppresses apoptosis and inflammatory signaling through its actions on the ERK1/2-induced autophagy in chondrocytes. We propose that curcumin should be explored further for the prophylactic treatment of osteoarthritis in humans and companion animals.

Defective postnatal endochondral bone development by chondrocyte-specific targeted expression of parathyroid hormone type 2 receptor.

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Panda, Dibyendu Kumar; Goltzman, David; Karaplis, Andrew C

2012-12-15

The human parathyroid hormone type 2 receptor (PTH2R) is activated by PTH and by tuberoinfundibular peptide of 39 residues (TIP39), the latter likely acting as its natural ligand. Although the receptor is expressed at highest levels in the nervous system, we have observed that both PTH2R and TIP39 are expressed in the newborn mouse growth plate, with the receptor localizing in the resting zone and the ligand TIP39 localizing exclusively in prehypertrophic and hypertrophic chondrocytes. To address the role of PTH2R in postnatal skeletal growth and development, Col2a1-hPTH2R (PTH2R-Tg) transgenic mice were generated. The mice were viable and of nearly normal size at birth. Expression of the transgene in the growth plate was limited to chondrocytes. We found that chondrocyte proliferation was decreased, as determined by in vivo BrdU labeling of proliferating chondrocytes and CDK4 and p21 expression in the growth plate of Col2a1-hPTH2R transgenic mice. Similarly, the differentiation and maturation of chondrocytes was delayed, as characterized by decreased Sox9 expression and weaker immunostaining for the chondrocyte differentiation markers collagen type II and type X and proteoglycans. As well, there was altered expression of Gdf5, Wdr5, and β-catenin, factors implicated in chondrocyte maturation, proliferation, and differentiation.These effects impacted on the process of endochondral ossification, resulting in delayed formation of the secondary ossification center, and diminished trabecular bone volume. The findings substantiate a role for PTH2R signaling in postnatal growth plate development and subsequent bone mass acquisition.

Expansion of bovine chondrocytes on microcarriers enhances redifferentiation

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Malda, J.; van Blitterswijk, Clemens; Grojec, M.; Martens, D.E.; Tramper, J.; Riesle, J.U.

2003-01-01

Functional cartilage implants for orthopedic surgery or in vitro tissue evaluation can be created from expanded chondrocytes and biodegradable scaffolds. Expansion of chondrocytes in two-dimensional culture systems results in their dedifferentiation. The hallmark of this process is the switch of

Indian hedgehog signaling triggers Nkx3.2 protein degradation during chondrocyte maturation

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Choi, Seung-Won; Jeong, Da-Un; Kim, Jeong-Ah; Lee, Boyoung; Joeng, Kyu Sang; Long, Fanxin; Kim, Dae-Won

2015-01-01

The Indian hedgehog (Ihh) pathway plays an essential role in facilitating chondrocyte hypertrophy and bone formation during skeletal development. Nkx3.2 is initially induced in chondrocyte precursor cells, maintained in early-stage chondrocytes, and down-regulated in terminal-stage chondrocytes. Consistent with these expression patterns, Nkx3.2 has been shown to enhance chondrocyte differentiation and cell survival, while inhibiting chondrocyte hypertrophy and apoptosis. Thus, in this work, we investigate whether Nkx3.2, an early stage chondrogenic factor, can be regulated by Ihh, a key regulator for chondrocyte hypertrophy. Here, we show that Ihh signaling can induce proteasomal degradation of Nkx3.2. In addition, we found that Ihh can suppress levels of Lrp (Wnt co-receptor) and Sfrp (Wnt antagonist) expression, which, in turn, may selectively enhance Lrp-independent non-canonical Wnt pathways in chondrocyte. In agreement with these findings, Ihh-induced Nkx3.2 degradation requires Wnt5a, which is capable of triggering Nkx3.2 degradation. Finally, we found that Nkx3.2 protein levels in chondrocytes are remarkably elevated in mice defective in Ihh signaling by deletion of either Ihh or Smoothened. Thus, these results suggest that Ihh/Wnt5a signaling may play a role in negative regulation of Nkx3.2 for appropriate progression of chondrocyte hypertrophy during chondrogenesis. PMID:22507129

Endogenous versus Exogenous Growth Factor Regulation of Articular Chondrocytes

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Shi, Shuiliang; Chan, Albert G.; Mercer, Scott; Eckert, George J.; Trippel, Stephen B.

2014-01-01

Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-ß1 stimulated these reparative functions, while endogenous TGF-ß1 had little effect. Endogenous TGF-ß1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-ß1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. PMID:24105960

The Regulatory Role of Signaling Crosstalk in Hypertrophy of MSCs and Human Articular Chondrocytes

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Zhong, Leilei; Huang, X; Karperien, Hermanus Bernardus Johannes; Post, Janine Nicole

2015-01-01

Hypertrophic differentiation of chondrocytes is a main barrier in application of mesenchymal stem cells (MSCs) for cartilage repair. In addition, hypertrophy occurs occasionally in osteoarthritis (OA). Here we provide a comprehensive review on recent literature describing signal pathways in the

Mechanical confinement regulates cartilage matrix formation by chondrocytes

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Lee, Hong-Pyo; Gu, Luo; Mooney, David J.; Levenston, Marc E.; Chaudhuri, Ovijit

2017-12-01

Cartilage tissue equivalents formed from hydrogels containing chondrocytes could provide a solution for replacing damaged cartilage. Previous approaches have often utilized elastic hydrogels. However, elastic stresses may restrict cartilage matrix formation and alter the chondrocyte phenotype. Here we investigated the use of viscoelastic hydrogels, in which stresses are relaxed over time and which exhibit creep, for three-dimensional (3D) culture of chondrocytes. We found that faster relaxation promoted a striking increase in the volume of interconnected cartilage matrix formed by chondrocytes. In slower relaxing gels, restriction of cell volume expansion by elastic stresses led to increased secretion of IL-1β, which in turn drove strong up-regulation of genes associated with cartilage degradation and cell death. As no cell-adhesion ligands are presented by the hydrogels, these results reveal cell sensing of cell volume confinement as an adhesion-independent mechanism of mechanotransduction in 3D culture, and highlight stress relaxation as a key design parameter for cartilage tissue engineering.

The epigenetic effect of glucosamine and a nuclear factor-kappa B (NF-kB) inhibitor on primary human chondrocytes - Implications for osteoarthritis

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Imagawa, Kei, E-mail: k.Imagawa@soton.ac.uk [University of Southampton Medical School, Bone and Joint Research Group, Southampton (United Kingdom); Tohoku University School of Medicine, Sendai (Japan); Andres, MC de [University of Southampton Medical School, Bone and Joint Research Group, Southampton (United Kingdom); Hashimoto, Ko [Hospital for Special Surgery, NY (United States); Pitt, Dominic [University of Southampton Medical School, Bone and Joint Research Group, Southampton (United Kingdom); Itoi, Eiji [Tohoku University School of Medicine, Sendai (Japan); Goldring, Mary B. [Hospital for Special Surgery, NY (United States); Roach, Helmtrud I.; Oreffo, Richard O.C. [University of Southampton Medical School, Bone and Joint Research Group, Southampton (United Kingdom)

2011-02-18

Research highlights: {yields} Glucosamine and a NF-kB inhibitor reduce inflammation in OA. {yields} Cytokine induced demethylation of CpG site in IL1{beta} promoter prevented by glucosamine. {yields} Glucosamine and NF-kB inhibitor have epigenetic effects on human chondrocytes. -- Abstract: Objective: Idiopathic osteoarthritis is the most common form of osteoarthritis (OA) world-wide and remains the leading cause of disability and the associated socio-economic burden in an increasing aging population. Traditionally, OA has been viewed as a degenerative joint disease characterized by progressive destruction of the articular cartilage and changes in the subchondral bone culminating in joint failure. However, the etiology of OA is multifactorial involving genetic, mechanical and environmental factors. Treatment modalities include analgesia, joint injection with steroids or hyaluronic acid, oral supplements including glucosamine and chondroitin sulfate, as well as physiotherapy. Thus, there is significant interest in the discovery of disease modifying agents. One such agent, glucosamine (GlcN) is commonly prescribed even though the therapeutic efficacy and mechanism of action remain controversial. Inflammatory cytokines, including IL-1{beta}, and proteinases such as MMP-13 have been implicated in the pathogenesis and progression of OA together with an associated CpG demethylation in their promoters. We have investigated the potential of GlcN to modulate NF-kB activity and cytokine-induced abnormal gene expression in articular chondrocytes and, critically, whether this is associated with an epigenetic process. Method: Human chondrocytes were isolated from the articular cartilage of femoral heads, obtained with ethical permission, following fractured neck of femur surgery. Chondrocytes were cultured for 5 weeks in six separate groups; (i) control culture, (ii) cultured with a mixture of 2.5 ng/ml IL-1{beta} and 2.5 ng/ml oncostatin M (OSM), (iii) cultured with 2 mM N

The epigenetic effect of glucosamine and a nuclear factor-kappa B (NF-kB) inhibitor on primary human chondrocytes - Implications for osteoarthritis

International Nuclear Information System (INIS)

Imagawa, Kei; Andres, MC de; Hashimoto, Ko; Pitt, Dominic; Itoi, Eiji; Goldring, Mary B.; Roach, Helmtrud I.; Oreffo, Richard O.C.

2011-01-01

Research highlights: → Glucosamine and a NF-kB inhibitor reduce inflammation in OA. → Cytokine induced demethylation of CpG site in IL1β promoter prevented by glucosamine. → Glucosamine and NF-kB inhibitor have epigenetic effects on human chondrocytes. -- Abstract: Objective: Idiopathic osteoarthritis is the most common form of osteoarthritis (OA) world-wide and remains the leading cause of disability and the associated socio-economic burden in an increasing aging population. Traditionally, OA has been viewed as a degenerative joint disease characterized by progressive destruction of the articular cartilage and changes in the subchondral bone culminating in joint failure. However, the etiology of OA is multifactorial involving genetic, mechanical and environmental factors. Treatment modalities include analgesia, joint injection with steroids or hyaluronic acid, oral supplements including glucosamine and chondroitin sulfate, as well as physiotherapy. Thus, there is significant interest in the discovery of disease modifying agents. One such agent, glucosamine (GlcN) is commonly prescribed even though the therapeutic efficacy and mechanism of action remain controversial. Inflammatory cytokines, including IL-1β, and proteinases such as MMP-13 have been implicated in the pathogenesis and progression of OA together with an associated CpG demethylation in their promoters. We have investigated the potential of GlcN to modulate NF-kB activity and cytokine-induced abnormal gene expression in articular chondrocytes and, critically, whether this is associated with an epigenetic process. Method: Human chondrocytes were isolated from the articular cartilage of femoral heads, obtained with ethical permission, following fractured neck of femur surgery. Chondrocytes were cultured for 5 weeks in six separate groups; (i) control culture, (ii) cultured with a mixture of 2.5 ng/ml IL-1β and 2.5 ng/ml oncostatin M (OSM), (iii) cultured with 2 mM N-acetyl GlcN (Sigma

Carnosol and Related Substances Modulate Chemokine and Cytokine Production in Macrophages and Chondrocytes

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Joseph Schwager

2016-04-01

Full Text Available Phenolic diterpenes present in Rosmarinus officinalis and Salvia officinalis have anti-inflammatory and chemoprotective effects. We investigated the in vitro effects of carnosol (CL, carnosic acid (CA, carnosic acid-12-methylether (CAME, 20-deoxocarnosol and abieta-8,11,13-triene-11,12,20-triol (ABTT in murine macrophages (RAW264.7 cells and human chondrocytes. The substances concentration-dependently reduced nitric oxide (NO and prostaglandin E2 (PGE2 production in LPS-stimulated macrophages (i.e., acute inflammation. They significantly blunted gene expression levels of iNOS, cytokines/interleukins (IL-1α, IL-6 and chemokines including CCL5/RANTES, CXCL10/IP-10. The substances modulated the expression of catabolic and anabolic genes in chondrosarcoma cell line SW1353 and in primary human chondrocytes that were stimulated by IL-1β (i.e., chronic inflammation In SW1353, catabolic genes like MMP-13 and ADAMTS-4 that contribute to cartilage erosion were down-regulated, while expression of anabolic genes including Col2A1 and aggrecan were shifted towards pre-pathophysiological homeostasis. CL had the strongest overall effect on inflammatory mediators, as well as on macrophage and chondrocyte gene expression. Conversely, CAME mainly affected catabolic gene expression, whereas ABTT had a more selectively altered interleukin and chemokine gene exprssion. CL inhibited the IL-1β induced nuclear translocation of NF-κBp65, suggesting that it primarily regulated via the NF-κB signalling pathway. Collectively, CL had the strongest effects on inflammatory mediators and chondrocyte gene expression. The data show that the phenolic diterpenes altered activity pattern of genes that regulate acute and chronic inflammatory processes. Since the substances affected catabolic and anabolic gene expression in cartilage cells in vitro, they may beneficially act on the aetiology of osteoarthritis.

The identification of CD163 expressing phagocytic chondrocytes in joint cartilage and its novel scavenger role in cartilage degradation.

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Kai Jiao

Full Text Available BACKGROUND: Cartilage degradation is a typical characteristic of arthritis. This study examined whether there was a subset of phagocytic chondrocytes that expressed the specific macrophage marker, CD163, and investigated their role in cartilage degradation. METHODS: Cartilage from the knee and temporomandibular joints of Sprague-Dawley rats was harvested. Cartilage degradation was experimentally-induced in rat temporomandibular joints, using published biomechanical dental methods. The expression levels of CD163 and inflammatory factors within cartilage, and the ability of CD163(+ chondrocytes to conduct phagocytosis were investigated. Cartilage from the knees of patients with osteoarthritis and normal cartilage from knee amputations was also investigated. RESULTS: In the experimentally-induced degrading cartilage from temporomandibular joints, phagocytes were capable of engulfing neighboring apoptotic and necrotic cells, and the levels of CD163, TNF-α and MMPs were all increased (P0.05. CD163(+ chondrocytes were found in the cartilage mid-zone of temporomandibular joints and knee from healthy, three-week old rats. Furthermore, an increased number of CD163(+ chondrocytes with enhanced phagocytic activity were present in Col-II(+ chondrocytes isolated from the degraded cartilage of temporomandibular joints in the eight-week experimental group compared with their age-matched controls. Increased number with enhanced phagocytic activity of CD163(+ chondrocytes were also found in isolated Col-II(+ chondrocytes stimulated with TNF-α (P<0.05. Mid-zone distribution of CD163(+ cells accompanied with increased expression of CD163 and TNF-α were further confirmed in the isolated Col-II(+ chondrocytes from the knee cartilage of human patients with osteoarthritis, in contrast to the controls (both P<0.05. CONCLUSIONS: An increased number of CD163(+ chondrocytes with enhanced phagocytic activity were discovered within degraded joint cartilage, indicating a

Reduction of Environmental Temperature Mitigates Local Anesthetic Cytotoxicity in Bovine Articular Chondrocytes

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Tarik Onur, Alexis Dang

2014-09-01

Full Text Available The purpose of this study was to assess whether reducing environmental temperature will lead to increased chondrocyte viability following injury from a single-dose of local anesthetic treatment. Bovine articular chondrocytes from weight bearing portions of femoral condyles were harvested and cultured. 96-well plates were seeded with 15,000 chondrocytes per well. Chondrocytes were treated with one of the following conditions: ITS Media, 1x PBS, 2% lidocaine, 0.5% bupivacaine, or 0.5% ropivacaine. Each plate was then incubated at 37°C, 23°C, or 4°C for one hour and then returned to media at 37°C. Chondrocyte viability was assessed 24 hours after treatment. Chondrocyte viability is presented as a ratio of the fluorescence of the treatment group over the average of the media group at that temperature (ratio ± SEM. At 37°C, lidocaine (0.35 ± 0.04 and bupivacaine (0.30 ± 0.05 treated chondrocytes show low cell viability when compared to the media (1.00 ± 0.03 control group (p < 0.001. Lidocaine treated chondrocytes were significantly more viable at 23°C (0.84 ± 0.08 and 4°C (0.86±0.085 than at 37°C (p < 0.001. Bupivacaine treated chondrocytes were significantly more viable at 4°C (0.660 ± 0.073 than at 37°C or 23°C (0.330 ± 0.069 (p < 0.001 and p = 0.002 respectively. Reducing the temperature from 37°C to 23°C during treatment with lidocaine increases chondrocyte viability following injury. Chondrocytes treated with bupivacaine can be rescued by reducing the temperature to 4°C.

Enhanced hyaline cartilage matrix synthesis in collagen sponge scaffolds by using siRNA to stabilize chondrocytes phenotype cultured with bone morphogenetic protein-2 under hypoxia.

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Legendre, Florence; Ollitrault, David; Hervieu, Magalie; Baugé, Catherine; Maneix, Laure; Goux, Didier; Chajra, Hanane; Mallein-Gerin, Frédéric; Boumediene, Karim; Galera, Philippe; Demoor, Magali

2013-07-01

Cartilage healing by tissue engineering is an alternative strategy to reconstitute functional tissue after trauma or age-related degeneration. However, chondrocytes, the major player in cartilage homeostasis, do not self-regenerate efficiently and lose their phenotype during osteoarthritis. This process is called dedifferentiation and also occurs during the first expansion step of autologous chondrocyte implantation (ACI). To ensure successful ACI therapy, chondrocytes must be differentiated and capable of synthesizing hyaline cartilage matrix molecules. We therefore developed a safe procedure for redifferentiating human chondrocytes by combining appropriate physicochemical factors: hypoxic conditions, collagen scaffolds, chondrogenic factors (bone morphogenetic protein-2 [BMP-2], and insulin-like growth factor I [IGF-I]) and RNA interference targeting the COL1A1 gene. Redifferentiation of dedifferentiated chondrocytes was evaluated using gene/protein analyses to identify the chondrocyte phenotypic profile. In our conditions, under BMP-2 treatment, redifferentiated and metabolically active chondrocytes synthesized a hyaline-like cartilage matrix characterized by type IIB collagen and aggrecan molecules without any sign of hypertrophy or osteogenesis. In contrast, IGF-I increased both specific and noncharacteristic markers (collagens I and X) of chondrocytes. The specific increase in COL2A1 gene expression observed in the BMP-2 treatment was shown to involve the specific enhancer region of COL2A1 that binds the trans-activators Sox9/L-Sox5/Sox6 and Sp1, which are associated with a decrease in the trans-inhibitors of COL2A1, c-Krox, and p65 subunit of NF-kappaB. Our procedure in which BMP-2 treatment under hypoxia is associated with a COL1A1 siRNA, significantly increased the differentiation index of chondrocytes, and should offer the opportunity to develop new ACI-based therapies in humans.

Characterization and chondrocyte differentiation stage-specific expression of KRAB zinc-finger protein gene ZNF470

International Nuclear Information System (INIS)

Hering, Thomas M.; Kazmi, Najam H.; Huynh, Tru D.; Kollar, John; Xu, Laura; Hunyady, Aaron B.; Johnstone, Brian

2004-01-01

As part of a study to identify novel transcriptional regulators of chondrogenesis-related gene expression, we have cloned and characterized cDNA for zinc-finger protein 470 (ZNF470), the human ortholog of which encodes a 717 amino acid residue protein containing 17 Cys 2 His 2 zinc-finger domains, as well as KRAB-A and KRAB-B motifs. The cDNA library used to isolate the initial ZNF470 clone was prepared from human bone marrow-derived mesenchymal progenitor cells at an intermediate stage of chondrogenic differentiation. We have determined the intron-exon structure of the human ZNF470 gene, which has been mapped to a zinc-finger cluster in a known imprinted region of human chromosome 19q13.4. ZNF470 is expressed at high levels in human testis and is expressed at low or undetectible levels in other adult tissues. Human ZNF470 expressed in mammalian cells as an EGFP fusion protein localizes predominantly to the nucleus, consistent with a role in transcriptional regulation. ZNF470, analyzed by quantitative real time PCR, was transiently expressed before the maximal expression of COL2A1 during chondrogenic differentiation in vitro. We have also characterized the bovine ortholog of human ZNF470, which encodes a 508 amino acid residue protein having 10 zinc-finger domains. A bovine ZNF470 cDNA clone was used to examine expression of ZNF470 in bovine articular chondrocytes treated with retinoic acid to stimulate dedifferentiation. Bovine ZNF470 expression was undetectable in freshly isolated bovine articular chondrocytes, but was dramatically upregulated in dedifferentiated retinoic acid-treated chondrocytes. These results, in two model systems, suggest a possible role for ZNF470 in the regulation of chondrogenesis-specific gene expression

Dexamethasone stimulates expression of C-type Natriuretic Peptide in chondrocytes

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Beier Frank

2006-11-01

Full Text Available Abstract Background Growth of endochondral bones is regulated through the activity of cartilaginous growth plates. Disruption of the physiological patterns of chondrocyte proliferation and differentiation – such as in endocrine disorders or in many different genetic diseases (e.g. chondrodysplasias – generally results in dwarfism and skeletal defects. For example, glucocorticoid administration in children inhibits endochondral bone growth, but the molecular targets of these hormones in chondrocytes remain largely unknown. In contrast, recent studies have shown that C-type Natriuretic Peptide (CNP is an important anabolic regulator of cartilage growth, and loss-of-function mutations in the human CNP receptor gene cause dwarfism. We asked whether glucocorticoids could exert their activities by interfering with the expression of CNP or its downstream signaling components. Methods Primary mouse chondrocytes in monolayer where incubated with the synthetic glucocorticoid Dexamethasone (DEX for 12 to 72 hours. Cell numbers were determined by counting, and real-time PCR was performed to examine regulation of genes in the CNP signaling pathway by DEX. Results We show that DEX does influence expression of key genes in the CNP pathway. Most importantly, DEX significantly increases RNA expression of the gene encoding CNP itself (Nppc. In addition, DEX stimulates expression of Prkg2 (encoding cGMP-dependent protein kinase II and Npr3 (natriuretic peptide decoy receptor genes. Conversely, DEX was found to down-regulate the expression of the gene encoding its receptor, Nr3c1 (glucocorticoid receptor, as well as the Npr2 gene (encoding the CNP receptor. Conclusion Our data suggest that the growth-suppressive activities of DEX are not due to blockade of CNP signaling. This study reveals a novel, unanticipated relationship between glucocorticoid and CNP signaling and provides the first evidence that CNP expression in chondrocytes is regulated by endocrine

Autologous Chondrocyte Implantation in Osteoarthritic Surroundings

DEFF Research Database (Denmark)

Ossendorff, Robert; Grad, Sibylle; Stoddart, Martin J

2018-01-01

BACKGROUND: Autologous chondrocyte implantation (ACI) fails in up to 20% of cases. Advanced intra-articular degeneration paired with an inflammatory environment may be closely related to implantation failure. Certain cytokines have been identified to play a major role during early osteoarthritis....... PURPOSE: To investigate the effects of tumor necrosis factor α (TNFα) and its potential inhibition by adalimumab on cartilage regeneration in an in vitro model of ACI. STUDY DESIGN: Controlled laboratory study. METHODS: Bovine articular chondrocytes were cultivated and transferred at passage 3 to fibrin...

The Signaling Pathways Involved in Chondrocyte Differentiation and Hypertrophic Differentiation

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Jianmei Li

2016-01-01

Full Text Available Chondrocytes communicate with each other mainly via diffusible signals rather than direct cell-to-cell contact. The chondrogenic differentiation of mesenchymal stem cells (MSCs is well regulated by the interactions of varieties of growth factors, cytokines, and signaling molecules. A number of critical signaling molecules have been identified to regulate the differentiation of chondrocyte from mesenchymal progenitor cells to their terminal maturation of hypertrophic chondrocytes, including bone morphogenetic proteins (BMPs, SRY-related high-mobility group-box gene 9 (Sox9, parathyroid hormone-related peptide (PTHrP, Indian hedgehog (Ihh, fibroblast growth factor receptor 3 (FGFR3, and β-catenin. Except for these molecules, other factors such as adenosine, O2 tension, and reactive oxygen species (ROS also have a vital role in cartilage formation and chondrocyte maturation. Here, we outlined the complex transcriptional network and the function of key factors in this network that determine and regulate the genetic program of chondrogenesis and chondrocyte differentiation.

Reduced primary cilia length and altered Arl13b expression are associated with deregulated chondrocyte Hedgehog signaling in alkaptonuria.

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Thorpe, Stephen D; Gambassi, Silvia; Thompson, Clare L; Chandrakumar, Charmilie; Santucci, Annalisa; Knight, Martin M

2017-09-01

Alkaptonuria (AKU) is a rare inherited disease resulting from a deficiency of the enzyme homogentisate 1,2-dioxygenase which leads to the accumulation of homogentisic acid (HGA). AKU is characterized by severe cartilage degeneration, similar to that observed in osteoarthritis. Previous studies suggest that AKU is associated with alterations in cytoskeletal organization which could modulate primary cilia structure/function. This study investigated whether AKU is associated with changes in chondrocyte primary cilia and associated Hedgehog signaling which mediates cartilage degradation in osteoarthritis. Human articular chondrocytes were obtained from healthy and AKU donors. Additionally, healthy chondrocytes were treated with HGA to replicate AKU pathology (+HGA). Diseased cells exhibited shorter cilia with length reductions of 36% and 16% in AKU and +HGA chondrocytes respectively, when compared to healthy controls. Both AKU and +HGA chondrocytes demonstrated disruption of the usual cilia length regulation by actin contractility. Furthermore, the proportion of cilia with axoneme breaks and bulbous tips was increased in AKU chondrocytes consistent with defective regulation of ciliary trafficking. Distribution of the Hedgehog-related protein Arl13b along the ciliary axoneme was altered such that its localization was increased at the distal tip in AKU and +HGA chondrocytes. These changes in cilia structure/trafficking in AKU and +HGA chondrocytes were associated with a complete inability to activate Hedgehog signaling in response to exogenous ligand. Thus, we suggest that altered responsiveness to Hedgehog, as a consequence of cilia dysfunction, may be a contributing factor in the development of arthropathy highlighting the cilium as a novel target in AKU. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals Inc.

Chondrocyte survival in osteochondral transplant cylinders depends on the harvesting technique.

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Hafke, Benedikt; Petri, Maximilian; Suero, Eduardo; Neunaber, Claudia; Kwisda, Sebastian; Krettek, Christian; Jagodzinski, Michael; Omar, Mohamed

2016-07-01

In autologous osteochondral transplantation, the edges of the harvested plug are particularly susceptible to mechanical or thermal damage to the chondrocytes. We hypothesised that the applied harvesting device has an impact on chondrocyte vitality. Both knees of five blackhead sheep (ten knees) underwent open osteochondral plug harvesting with three different circular harvesting devices (osteoarticular transfer system harvester [OATS; diameter 8 mm; Arthrex, Munich, Germany], diamond cutter [DC; diameter 8.35 mm; Karl Storz, Tuttlingen, Germany] and hollow reamer with cutting crown [HRCC; diameter 7 mm; Dannoritzer, Tuttlingen, Germany]) from distinctly assigned anatomical sites of the knee joint. The rotary cutters (DC and HRCC) were either used with (+) or without cooling (-). Surgical cuts of the cartilage with a scalpel blade were chosen as control method. After cryotomy cutting, chondrocyte vitality was assessed using fluorescence microscopy and a Live/Dead assay. There were distinct patterns of chondrocyte vitality, with reproducible accumulations of dead chondrocytes along the harvesting edge. No statistical difference in chondrocyte survivorship was seen between the OATS technique and the control method, or between the HRCC+ technique and the control method (P > 0.05). The DC+, HRCC- and DC- techniques yielded significantly lower chondrocyte survival rates compared with the control method (P vitality.

Endogenous versus exogenous growth factor regulation of articular chondrocytes.

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Shi, Shuiliang; Chan, Albert G; Mercer, Scott; Eckert, George J; Trippel, Stephen B

2014-01-01

Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-β1 stimulated these reparative functions, while endogenous TGF-β1 had little effect. Endogenous TGF-β1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-β1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. This article is a U.S. Government work and is in the public domain in the USA.

NF-kappaB specifically activates BMP-2 gene expression in growth plate chondrocytes in vivo and in a chondrocyte cell line in vitro.

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Feng, Jian Q; Xing, Lianping; Zhang, Jiang-Hong; Zhao, Ming; Horn, Diane; Chan, Jeannie; Boyce, Brendan F; Harris, Stephen E; Mundy, Gregory R; Chen, Di

2003-08-01

Bone morphogenetic protein-2 (BMP-2) regulates growth plate chondrogenesis during development and postnatal bone growth, but the control mechanisms of BMP-2 expression in growth plate chondrocytes are unknown. Here we have used both in vitro and in vivo approaches to demonstrate that transcription factor, NF-kappaB, regulates BMP-2 gene expression in chondrocytes. Two putative NF-kappaB response elements were found in the -2712/+165 region of the BMP-2 gene. Cotransfection of mutant I-kappaBalpha expression plasmids with BMP-2 promoter-luciferase reporters into TMC-23 chondrocyte cell line suppressed BMP-2 transcription. Mutations in NF-kappaB response elements in the BMP-2 gene lead to decreases in BMP-2 promoter activity. Electrophoretic mobility shift assay using nuclear extracts from TMC-23 chondrocytic cells revealed that the NF-kappaB subunits p50 and p65 bound to the NF-kappaB response elements of the BMP-2 gene. Thus, NF-kappaB may positively regulate BMP-2 gene transcription. Consistent with these findings, expression of BMP-2 mRNA was significantly reduced in growth plate chondrocytes in NF-kappaB p50/p52 dKO mice, which associated with decreased numbers of 5-bromo-2'-deoxyuridine (BrdUrd)-positive cells in the proliferating zone of growth plate in these mice. Therefore, in postnatal growth plate chondrocytes, expression of BMP-2 is regulated by NF-kappaB, which may play an important role in chondrogenesis.

The impact of polyphenols on chondrocyte growth and survival: a preliminary report

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Salvador Fernández-Arroyo

2015-10-01

Full Text Available Background: Imbalances in the functional binding of fibroblast growth factors (FGFs to their receptors (FGFRs have consequences for cell proliferation and differentiation that in chondrocytes may lead to degraded cartilage. The toxic, proinflammatory, and oxidative response of cytokines and FGFs can be mitigated by dietary polyphenols. Objective: We explored the possible effects of polyphenols in the management of osteoarticular diseases using a model based on the transduction of a mutated human FGFR3 (G380R in murine chondrocytes. This mutation is present in most cases of skeletal dysplasia and is responsible for the overexpression of FGFR3 that, in the presence of its ligand, FGF9, results in toxic effects leading to altered cellular growth. Design: Different combinations of dietary polyphenols derived from plant extracts were assayed in FGFR3 (G380R mutated murine chondrocytes, exploring cell survival, chloride efflux, extracellular matrix (ECM generation, and grade of activation of mitogen-activated protein kinases. Results: Bioactive compounds from Hibiscus sabdariffa reversed the toxic effects of FGF9 and restored normal growth, suggesting a probable translation to clinical requests in humans. Indeed, these compounds activated the intracellular chloride efflux, increased ECM generation, and stimulated cell proliferation. The inhibition of mitogen-activated protein kinase phosphorylation was interpreted as the main mechanism governing these beneficial effects. Conclusions: These findings support the rationale behind the encouragement of the development of drugs that repress the overexpression of FGFRs and suggest the dietary incorporation of supplementary nutrients in the management of degraded cartilage.

Widespread epigenomic, transcriptomic and proteomic differences between hip osteophytic and articular chondrocytes in osteoarthritis.

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Steinberg, Julia; Brooks, Roger A; Southam, Lorraine; Bhatnagar, Sahir; Roumeliotis, Theodoros I; Hatzikotoulas, Konstantinos; Zengini, Eleni; Wilkinson, J Mark; Choudhary, Jyoti S; McCaskie, Andrew W; Zeggini, Eleftheria

2018-05-08

To identify molecular differences between chondrocytes from osteophytic and articular cartilage tissue from OA patients. We investigated genes and pathways by combining genome-wide DNA methylation, RNA sequencing and quantitative proteomics in isolated primary chondrocytes from the cartilaginous layer of osteophytes and matched areas of low- and high-grade articular cartilage across nine patients with OA undergoing hip replacement surgery. Chondrocytes from osteophytic cartilage showed widespread differences to low-grade articular cartilage chondrocytes. These differences were similar to, but more pronounced than, differences between chondrocytes from osteophytic and high-grade articular cartilage, and more pronounced than differences between high- and low-grade articular cartilage. We identified 56 genes with significant differences between osteophytic chondrocytes and low-grade articular cartilage chondrocytes on all three omics levels. Several of these genes have known roles in OA, including ALDH1A2 and cartilage oligomeric matrix protein, which have functional genetic variants associated with OA from genome-wide association studies. An integrative gene ontology enrichment analysis showed that differences between osteophytic and low-grade articular cartilage chondrocytes are associated with extracellular matrix organization, skeletal system development, platelet aggregation and regulation of ERK1 and ERK2 cascade. We present a first comprehensive view of the molecular landscape of chondrocytes from osteophytic cartilage as compared with articular cartilage chondrocytes from the same joints in OA. We found robust changes at genes relevant to chondrocyte function, providing insight into biological processes involved in osteophyte development and thus OA progression.

Unphysiologically high magnesium concentrations support chondrocyte proliferation and redifferentiation.

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Feyerabend, Frank; Witte, Frank; Kammal, Michael; Willumeit, Regine

2006-12-01

The effect of unphysiologically high extracellular magnesium concentrations on chondrocytes, induced by the supplementation of magnesium sulfate, was studied using a 3-phase tissue engineering model. The experiments showed that chondrocyte proliferation and redifferentiation, on the gene and protein expression level, are enhanced. A negative influence was found during chondrogenesis where an inhibition of extracellular matrix formation was observed. In addition, a direct impact on chondrocyte metabolism, elevated magnesium concentrations also affected growth factor effectiveness by consecutive influences during chondrogenesis. All observations were dosage dependent. The results of this study indicate that magnesium may be a useful tool for cartilage tissue engineering.

Effect of Collagen Type I or Type II on Chondrogenesis by Cultured Human Articular Chondrocytes

NARCIS (Netherlands)

Rutgers, M.; Saris, Daniël B.F.; Vonk, L.A.; van Rijen, M.H.P.; Akrum, V.; Langeveld, D.; van Boxtel, A.; Dhert, W.J.A.; Creemers, L.B.

2013-01-01

Introduction: Current cartilage repair procedures using autologous chondrocytes rely on a variety of carriers for implantation. Collagen types I and II are frequently used and valuable properties of both were shown earlier in vitro, although a preference for either was not demonstrated. Recently,

3D Bioprinting Human Chondrocytes with Nanocellulose-Alginate Bioink for Cartilage Tissue Engineering Applications.

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Markstedt, Kajsa; Mantas, Athanasios; Tournier, Ivan; Martínez Ávila, Héctor; Hägg, Daniel; Gatenholm, Paul

2015-05-11

The introduction of 3D bioprinting is expected to revolutionize the field of tissue engineering and regenerative medicine. The 3D bioprinter is able to dispense materials while moving in X, Y, and Z directions, which enables the engineering of complex structures from the bottom up. In this study, a bioink that combines the outstanding shear thinning properties of nanofibrillated cellulose (NFC) with the fast cross-linking ability of alginate was formulated for the 3D bioprinting of living soft tissue with cells. Printability was evaluated with concern to printer parameters and shape fidelity. The shear thinning behavior of the tested bioinks enabled printing of both 2D gridlike structures as well as 3D constructs. Furthermore, anatomically shaped cartilage structures, such as a human ear and sheep meniscus, were 3D printed using MRI and CT images as blueprints. Human chondrocytes bioprinted in the noncytotoxic, nanocellulose-based bioink exhibited a cell viability of 73% and 86% after 1 and 7 days of 3D culture, respectively. On the basis of these results, we can conclude that the nanocellulose-based bioink is a suitable hydrogel for 3D bioprinting with living cells. This study demonstrates the potential use of nanocellulose for 3D bioprinting of living tissues and organs.

Mechanical properties and structure-function relationships of human chondrocyte-seeded cartilage constructs after in vitro culture.

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Middendorf, Jill M; Griffin, Darvin J; Shortkroff, Sonya; Dugopolski, Caroline; Kennedy, Stephen; Siemiatkoski, Joseph; Cohen, Itai; Bonassar, Lawrence J

2017-10-01

Autologous Chondrocyte Implantation (ACI) is a widely recognized method for the repair of focal cartilage defects. Despite the accepted use, problems with this technique still exist, including graft hypertrophy, damage to surrounding tissue by sutures, uneven cell distribution, and delamination. Modified ACI techniques overcome these challenges by seeding autologous chondrocytes onto a 3D scaffold and securing the graft into the defect. Many studies on these tissue engineered grafts have identified the compressive properties, but few have examined frictional and shear properties as suggested by FDA guidance. This study is the first to perform three mechanical tests (compressive, frictional, and shear) on human tissue engineered cartilage. The objective was to understand the complex mechanical behavior, function, and changes that occur with time in these constructs grown in vitro using compression, friction, and shear tests. Safranin-O histology and a DMMB assay both revealed increased sulfated glycosaminoglycan (sGAG) content in the scaffolds with increased maturity. Similarly, immunohistochemistry revealed increased lubricin localization on the construct surface. Confined compression and friction tests both revealed improved properties with increased construct maturity. Compressive properties correlated with the sGAG content, while improved friction coefficients were attributed to increased lubricin localization on the construct surfaces. In contrast, shear properties did not improve with increased culture time. This study suggests the various mechanical and biological properties of tissue engineered cartilage improve at different rates, indicating thorough mechanical evaluation of tissue engineered cartilage is critical to understanding the performance of repaired cartilage. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2298-2306, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Chondrocyte differentiation for auricular cartilage reconstruction using a chitosan based hydrogel.

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García-López, J; Garciadiego-Cázares, D; Melgarejo-Ramírez, Y; Sánchez-Sánchez, R; Solís-Arrieta, L; García-Carvajal, Z; Sánchez-Betancourt, J I; Ibarra, C; Luna-Bárcenas, G; Velasquillo, C

2015-12-01

Tissue engineering with the use of biodegradable and biocompatible scaffolds is an interesting option for ear repair. Chitosan-Polyvinyl alcohol-Epichlorohydrine hydrogel (CS-PVA-ECH) is biocompatible and displays appropriate mechanical properties to be used as a scaffold. The present work, studies the potential of CS-PVA-ECH scaffolds seeded with chondrocytes to develop elastic cartilage engineered-neotissues. Chondrocytes isolated from rabbit and swine elastic cartilage were independently cultured onto CS-PVA-ECH scaffolds for 20 days to form the appropriate constructs. Then, in vitro cell viability and morphology were evaluated by calcein AM and EthD-1 assays and Scanning Electron Microscopy (SEM) respectively, and the constructs were implanted in nu/nu mice for four months, in order to evaluate the neotissue formation. Histological analysis of the formed neotissues was performed by Safranin O, Toluidine blue (GAG's), Verhoeff-Van Gieson (elastic fibers), Masson's trichrome (collagen) and Von Kossa (Calcium salts) stains and SEM. Results indicate appropriate cell viability, seeded with rabbit or swine chondrocyte constructs; nevertheless, upon implantation the constructs developed neotissues with different characteristics depending on the animal species from which the seeded chondrocytes came from. Neotissues developed from swine chondrocytes were similar to auricular cartilage, while neotissues from rabbit chondrocytes were similar to hyaline cartilage and eventually they differentiate to bone. This result suggests that neotissue characteristics may be influenced by the animal species source of the chondrocytes isolated.

Bioluminescence imaging of chondrocytes in rabbits by intraarticular injection of D-luciferin

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Moon, Sung Min; Min, Jung Joon; Kim, Sung Mi; Bom, Hee Seung [Chonnam National University Medical School, Gwangju (Korea, Republic of); Oh, Suk Jung; Kang, Han Saem; Kim, Kwang Yoon [ECOBIO INC., Gwangju (Korea, Republic of); Kim, Young Ho [College of Natural Science, Chosun University, Gwangju (Korea, Republic of)

2007-02-15

Luciferase is one of the most commonly used reporter enzymes in the field of in vivo optical imaging. D-luciferin, the substrate for firefly luciferase has very high cost that allows this kind of experiment limited to small animals such as mice and rats. In this current study, we validated local injection of D-luciferin in the articular capsule for bioluminescence imaging in rabbits. Chondrocytes were cultured and infected by replication-defective adenoviral vector encoding firefly luciferase (Fluc). Chondrocytes expressing Fluc were injected or implanted in the left knee joint. The rabbits underwent optical imaging studies after local injection of D-luciferin at 1, 5, 7, 9 days after cellular administration. We sought whether optimal imaging signals was could be by a cooled CCD camera after local injection of D-luciferin. Imaging signal was not observed from the left knee joint after intraperitoneal injection of D-luciferin (15 mg/kg), whereas it was observed after intraarticular injection. Photon intensity from the left knee joint of rabbits was compared between cell injected and implanted groups after intraarticular injection of D-luciferin. During the period of imaging studies, photon intensity of the cell implanted group was 5-10 times higher than that of the cell injected group. We successfully imaged chondrocytes expressing Fluc after intraarticular injection of D-luciferin. This technique may be further applied to develop new drugs for knee joint disease.

Dynamic compression of chondrocyte-agarose constructs reveals new candidate mechanosensitive genes.

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Carole Bougault

Full Text Available Articular cartilage is physiologically exposed to repeated loads. The mechanical properties of cartilage are due to its extracellular matrix, and homeostasis is maintained by the sole cell type found in cartilage, the chondrocyte. Although mechanical forces clearly control the functions of articular chondrocytes, the biochemical pathways that mediate cellular responses to mechanical stress have not been fully characterised. The aim of our study was to examine early molecular events triggered by dynamic compression in chondrocytes. We used an experimental system consisting of primary mouse chondrocytes embedded within an agarose hydrogel; embedded cells were pre-cultured for one week and subjected to short-term compression experiments. Using Western blots, we demonstrated that chondrocytes maintain a differentiated phenotype in this model system and reproduce typical chondrocyte-cartilage matrix interactions. We investigated the impact of dynamic compression on the phosphorylation state of signalling molecules and genome-wide gene expression. After 15 min of dynamic compression, we observed transient activation of ERK1/2 and p38 (members of the mitogen-activated protein kinase (MAPK pathways and Smad2/3 (members of the canonical transforming growth factor (TGF-β pathways. A microarray analysis performed on chondrocytes compressed for 30 min revealed that only 20 transcripts were modulated more than 2-fold. A less conservative list of 325 modulated genes included genes related to the MAPK and TGF-β pathways and/or known to be mechanosensitive in other biological contexts. Of these candidate mechanosensitive genes, 85% were down-regulated. Down-regulation may therefore represent a general control mechanism for a rapid response to dynamic compression. Furthermore, modulation of transcripts corresponding to different aspects of cellular physiology was observed, such as non-coding RNAs or primary cilium. This study provides new insight into how

Characterization of collagenase-3 binding and internalization by rabbit chondrocytes

International Nuclear Information System (INIS)

Raggatt, L.J.; Choundhury, I.; Williams, S.

2002-01-01

Full text: Collagenase-3 (MMP-13) is an extracellular matrix metalloproteinase that cleaves type II collagen, the major protein component of cartilage, with high specificity. Several studies have identified increased levels of MMP-13 in arthritic synovial fluid where it may contribute to matrix destruction in this disease. Our laboratory has previously documented a process where by osteoblastic cells remove MMP-13 from the surrounding milieu by binding the enzyme to a specific receptor. The enzyme is then internalized and degraded through the actions of the endocytotic receptor, the low-density lipoprotein receptor-related protein (LRP). Such a mechanism provides for a controlled elimination of a potentially destructive enzyme from the extracellular environment. This process of MMP-13 internalization also occurs in chondrocytes and is significantly reduced in OA chondrocytes. We are currently characterizing the internalization of MMP-13 in normal rabbit chondrocytes. Primary rabbit chondrocytes were harvested and cultured in monolayers for three passages. Reverse transcription polymerase chain reaction (RT-PCR) was used to asses the cell phenotype during the culture period and the rabbit chondrocytes were found to express the cartilage specific genes aggrecan and type II collagen throughout this time. 125I-MMP-13 was used to assess the ability of the rabbit chondrocytes to bind MMP-13. Appreciable specific cell-association of MMP-13 was detected after 10 mm of exposure to the ligand and equilibrium was obtained after 2 h. After identifying the time to equilibrium we determined whether binding was saturable by incubating the chondrocytes with increasing concentrations of 125I-MMP-13 ranging from 0 to 100 nM at 4 deg C for 2h. The amount of specifically associated MMP-13 approached saturation at 75 nM, allowing assessment of the receptor kinetics. Finally, we have assessed the ability of rabbit chondrocytes to internalize a single cohort of 125I-MMP-13 over time at

Chondrocytic Atf4 regulates osteoblast differentiation and function via Ihh.

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Wang, Weiguang; Lian, Na; Ma, Yun; Li, Lingzhen; Gallant, Richard C; Elefteriou, Florent; Yang, Xiangli

2012-02-01

Atf4 is a leucine zipper-containing transcription factor that activates osteocalcin (Ocn) in osteoblasts and indian hedgehog (Ihh) in chondrocytes. The relative contribution of Atf4 in chondrocytes and osteoblasts to the regulation of skeletal development and bone formation is poorly understood. Investigations of the Atf4(-/-);Col2a1-Atf4 mouse model, in which Atf4 is selectively overexpressed in chondrocytes in an Atf4-null background, demonstrate that chondrocyte-derived Atf4 regulates osteogenesis during development and bone remodeling postnatally. Atf4 overexpression in chondrocytes of the Atf4(-/-);Col2a1-Atf4 double mutants corrects the reduction in stature and limb in Atf4(-/-) embryos and rectifies the decrease in Ihh expression, Hh signaling, proliferation and accelerated hypertrophy that characterize the Atf4(-/-) developing growth plate cartilages. Unexpectedly, this genetic manipulation also restores the expression of osteoblastic marker genes, namely Ocn and bone sialoprotein, in Atf4(-/-) developing bones. In Atf4(-/-);Col2a1-Atf4 adult mice, all the defective bone parameters found in Atf4(-/-) mice, including bone volume, trabecular number and thickness, and bone formation rate, are rescued. In addition, the conditioned media of ex vivo cultures from wild-type or Atf4(-/-);Col2a1-Atf4, but not Atf4(-/-) cartilage, corrects the differentiation defects of Atf4(-/-) bone marrow stromal cells and Ihh-blocking antibody eliminates this effect. Together, these data indicate that Atf4 in chondrocytes is required for normal Ihh expression and for its paracrine effect on osteoblast differentiation. Therefore, the cell-autonomous role of Atf4 in chondrocytes dominates the role of Atf4 in osteoblasts during development for the control of early osteogenesis and skeletal growth.

Enhanced chondrocyte culture and growth on biologically inspired nanofibrous cell culture dishes.

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Bhardwaj, Garima; Webster, Thomas J

2016-01-01

Chondral and osteochondral defects affect a large number of people in which treatment options are currently limited. Due to its ability to mimic the natural nanofibrous structure of cartilage, this current in vitro study aimed at introducing a new scaffold, called XanoMatrix™, for cartilage regeneration. In addition, this same scaffold is introduced here as a new substrate onto which to study chondrocyte functions. Current studies on chondrocyte functions are limited due to nonbiologically inspired cell culture substrates. With its polyethylene terephthalate and cellulose acetate composition, good mechanical properties and nanofibrous structure resembling an extracellular matrix, XanoMatrix offers an ideal surface for chondrocyte growth and proliferation. This current study demonstrated that the XanoMatrix scaffolds promote chondrocyte growth and proliferation as compared with the Corning and Falcon surfaces normally used for chondrocyte cell culture. The XanoMatrix scaffolds also have greater hydrophobicity, three-dimensional surface area, and greater tensile strength, making them ideal candidates for alternative treatment options for chondral and osteochondral defects as well as cell culture substrates to study chondrocyte functions.

Rapid Chondrocyte Isolation for Tissue Engineering Applications: The Effect of Enzyme Concentration and Temporal Exposure on the Matrix Forming Capacity of Nasal Derived Chondrocytes

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Srujana Vedicherla

2017-01-01

Full Text Available Laboratory based processing and expansion to yield adequate cell numbers had been the standard in Autologous Disc Chondrocyte Transplantation (ADCT, Allogeneic Juvenile Chondrocyte Implantation (NuQu®, and Matrix-Induced Autologous Chondrocyte Implantation (MACI. Optimizing cell isolation is a key challenge in terms of obtaining adequate cell numbers while maintaining a vibrant cell population capable of subsequent proliferation and matrix elaboration. However, typical cell yields from a cartilage digest are highly variable between donors and based on user competency. The overall objective of this study was to optimize chondrocyte isolation from cartilaginous nasal tissue through modulation of enzyme concentration exposure (750 and 3000 U/ml and incubation time (1 and 12 h, combined with physical agitation cycles, and to assess subsequent cell viability and matrix forming capacity. Overall, increasing enzyme exposure time was found to be more detrimental than collagenase concentration for subsequent viability, proliferation, and matrix forming capacity (sGAG and collagen of these cells resulting in nonuniform cartilaginous matrix deposition. Taken together, consolidating a 3000 U/ml collagenase digest of 1 h at a ratio of 10 ml/g of cartilage tissue with physical agitation cycles can improve efficiency of chondrocyte isolation, yielding robust, more uniform matrix formation.

PEDF Is Associated with the Termination of Chondrocyte Phenotype and Catabolism of Cartilage Tissue.

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Klinger, P; Lukassen, S; Ferrazzi, F; Ekici, A B; Hotfiel, T; Swoboda, B; Aigner, T; Gelse, K

2017-01-01

Objective. To investigate the expression and target genes of pigment epithelium-derived factor (PEDF) in cartilage and chondrocytes, respectively. Methods. We analyzed the expression pattern of PEDF in different human cartilaginous tissues including articular cartilage, osteophytic cartilage, and fetal epiphyseal and growth plate cartilage, by immunohistochemistry and quantitative real-time (qRT) PCR. Transcriptome analysis after stimulation of human articular chondrocytes with rhPEDF was performed by RNA sequencing (RNA-Seq) and confirmed by qRT-PCR. Results. Immunohistochemically, PEDF could be detected in transient cartilaginous tissue that is prone to undergo endochondral ossification, including epiphyseal cartilage, growth plate cartilage, and osteophytic cartilage. In contrast, PEDF was hardly detected in healthy articular cartilage and in the superficial zone of epiphyses, regions that are characterized by a permanent stable chondrocyte phenotype. RNA-Seq analysis and qRT-PCR demonstrated that rhPEDF significantly induced the expression of a number of matrix-degrading factors including SAA1, MMP1, MMP3, and MMP13. Simultaneously, a number of cartilage-specific genes including COL2A1, COL9A2, COMP, and LECT were among the most significantly downregulated genes. Conclusions. PEDF represents a marker for transient cartilage during all neonatal and postnatal developmental stages and promotes the termination of cartilage tissue by upregulation of matrix-degrading factors and downregulation of cartilage-specific genes. These data provide the basis for novel strategies to stabilize the phenotype of articular cartilage and prevent its degradation.

Curcumin Inhibits Chondrocyte Hypertrophy of Mesenchymal Stem Cells through IHH and Notch Signaling Pathways.

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Cao, Zhen; Dou, Ce; Dong, Shiwu

2017-01-01

Using tissue engineering technique to repair cartilage damage caused by osteoarthritis is a promising strategy. However, the regenerated tissue usually is fibrous cartilage, which has poor mechanical characteristics compared to hyaline cartilage. Chondrocyte hypertrophy plays an important role in this process. Thus, it is very important to find out a suitable way to maintain the phenotype of chondrocytes and inhibit chondrocyte hypertrophy. Curcumin deriving from turmeric was reported with anti-inflammatory and anti-tumor pharmacological effects. However, the role of curcumin in metabolism of chondrocytes, especially in the chondrocyte hypertrophy remains unclear. Mesenchymal stem cells (MSCs) are widely used in cartilage tissue engineering as seed cells. So we investigated the effect of curcumin on chondrogenesis and chondrocyte hypertrophy in MSCs through examination of cell viability, glycosaminoglycan synthesis and specific gene expression. We found curcumin had no effect on expression of chondrogenic markers including Sox9 and Col2a1 while hypertrophic markers including Runx2 and Col10a1 were down-regulated. Further exploration showed that curcumin inhibited chondrocyte hypertrophy through Indian hedgehog homolog (IHH) and Notch signalings. Our results indicated curcumin was a potential agent in modulating cartilage homeostasis and maintaining chondrocyte phenotype.

Genetic modification of chondrocytes with insulin-like growth factor-1 enhances cartilage healing in an equine model.

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Goodrich, L R; Hidaka, C; Robbins, P D; Evans, C H; Nixon, A J

2007-05-01

correlated with increased collagen type II immunoreaction up to eight months. Genetic modification of chondrocytes with AdIGF-1 prior to transplantation improved early (four to nine weeks), and to a lesser degree long-term, cartilage healing in the equine model. The equine model of cartilage healing closely resembles human clinical cartilage repair. The results of this study suggest that cartilage healing can be enhanced through genetic modification of chondrocytes prior to transplantation.

Stimulation of chondrocytes in vitro by gene transfer with plasmids coding for epidermal growth factor (hEGF) and basic fibroblast growth factor (bFGF)

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Schmal, H; Mehlhorn, A T; Zwingmann, J

2005-01-01

Human epidermal growth factor (hEGF) and basic fibroblast growth factor (bFGF) influence critical characteristics of chondrocytes. The effects on metabolism and differentiation were evaluated following transfection using specific plasmids coding for both cytokines. Chondrocytes were isolated from...... of recombinant hEGF and bFGF resulted in a significant increase in cell proliferation and glucosaminoglycan production. Chondrocytes were transfected with vectors coding for either hEGF or bFGF and the production of these proteins was measured in supernatants by ELISA. Expression kinetics showed different...... patterns: hEGF was detectable 2.5 days following transfection and peaked at day 5.5, whereas bFGF-production reached its maximum 1.5 days after transfection, declining thereafter. Chondrocytes endogenously produced significant amounts of bFGF within 5 days following isolation. Proliferation of h...

Devitalisation of human cartilage by high hydrostatic pressure treatment: Subsequent cultivation of chondrocytes and mesenchymal stem cells on the devitalised tissue

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Hiemer, B.; Genz, B.; Jonitz-Heincke, A.; Pasold, J.; Wree, A.; Dommerich, S.; Bader, R.

2016-01-01

The regeneration of cartilage lesions still represents a major challenge. Cartilage has a tissue-specific architecture, complicating recreation by synthetic biomaterials. A novel approach for reconstruction is the use of devitalised cartilage. Treatment with high hydrostatic pressure (HHP) achieves devitalisation while biomechanical properties are remained. Therefore, in the present study, cartilage was devitalised using HHP treatment and the potential for revitalisation with chondrocytes and mesenchymal stem cells (MSCs) was investigated. The devitalisation of cartilage was performed by application of 480 MPa over 10 minutes. Effective cellular inactivation was demonstrated by the trypan blue exclusion test and DNA quantification. Histology and electron microscopy examinations showed undamaged cartilage structure after HHP treatment. For revitalisation chondrocytes and MSCs were cultured on devitalised cartilage without supplementation of chondrogenic growth factors. Both chondrocytes and MSCs significantly increased expression of cartilage-specific genes. ECM stainings showed neocartilage-like structure with positive AZAN staining as well as collagen type II and aggrecan deposition after three weeks of cultivation. Our results showed that HHP treatment caused devitalisation of cartilage tissue. ECM proteins were not influenced, thus, providing a scaffold for chondrogenic differentiation of MSCs and chondrocytes. Therefore, using HHP-treated tissue might be a promising approach for cartilage repair. PMID:27671122

The NAD-Dependent Deacetylase Sirtuin-1 Regulates the Expression of Osteogenic Transcriptional Activator Runt-Related Transcription Factor 2 (Runx2 and Production of Matrix Metalloproteinase (MMP-13 in Chondrocytes in Osteoarthritis

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Koh Terauchi

2016-06-01

Full Text Available Aging is one of the major pathologic factors associated with osteoarthritis (OA. Recently, numerous reports have demonstrated the impact of sirtuin-1 (Sirt1, which is the NAD-dependent deacetylase, on human aging. It has been demonstrated that Sirt1 induces osteogenic and chondrogenic differentiation of mesenchymal stem cells. However, the role of Sirt1 in the OA chondrocytes still remains unknown. We postulated that Sirt1 regulates a hypertrophic chondrocyte lineage and degeneration of articular cartilage through the activation of osteogenic transcriptional activator Runx2 and matrix metalloproteinase (MMP-13 in OA chondrocytes. To verify whether sirtuin-1 (Sirt1 regulates chondrocyte activity in OA, we studied expressions of Sirt1, Runx2 and production of MMP-13, and their associations in human OA chondrocytes. The expression of Sirt1 was ubiquitously observed in osteoarthritic chondrocytes; in contrast, Runx2 expressed in the osteophyte region in patients with OA and OA model mice. OA relating catabolic factor IL-1βincreased the expression of Runx2 in OA chondrocytes. OA chondrocytes, which were pretreated with Sirt1 inhibitor, inhibited the IL-1β-induced expression of Runx2 compared to the control. Since the Runx2 is a promotor of MMP-13 expression, Sirt1 inactivation may inhibit the Runx2 expression and the resultant down-regulation of MMP-13 production in chondrocytes. Our findings suggest thatSirt1 may regulate the expression of Runx2, which is the osteogenic transcription factor, and the production of MMP-13 from chondrocytes in OA. Since Sirt1 activity is known to be affected by several stresses, including inflammation and oxidative stress, as well as aging, SIRT may be involved in the development of OA.

Secondary chondrocyte-derived Ihh stimulates proliferation of periosteal cells during chick development.

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Buxton, Paul G; Hall, Brian; Archer, Charles W; Francis-West, Philippa

2003-10-01

The development of the skull is characterised by its dependence upon epigenetic influences. One of the most important of these is secondary chondrogenesis, which occurs following ossification within certain membrane bone periostea, as a result of biomechanical articulation. We have studied the genesis, character and function of the secondary chondrocytes of the quadratojugal of the chick between embryonic days 11 and 14. Analysis of gene expression revealed that secondary chondrocytes formed coincident with Sox9 upregulation from a precursor population expressing Cbfa1/Runx2: a reversal of the normal sequence. Such secondary chondrocytes rapidly acquired a phenotype that is a compound of prehypertrophic and hypertrophic chondrocytes, exited from the cell cycle and upregulated Ihh. Pulse and pulse/chase experiments with BrdU confirmed the germinal region as the highly proliferative source of the secondary chondrocytes, which formed by division of chondrocyte-committed precursors. By blocking Hh signalling in explant cultures we show that the enhanced proliferation of the germinal region surrounding the secondary chondrocytes derives from this Ihh source. Additionally, in vitro studies on membrane bone periosteal cells (non-germinal region) demonstrated that these cells can also respond to Ihh, and do so both by enhanced proliferation and precocious osteogenesis. Despite the pro-osteogenic effects of Ihh on periosteal cell differentiation, mechanical articulation of the quadratojugal/quadrate joint in explant culture revealed a negative role for articulation in the regulation of osteocalcin by germinal region descendants. Thus, the mechanical stimulus that is the spur to secondary chondrocyte formation appears able to override the osteogenic influence of Ihh on the periosteum, but does not interfere with the cell cycle-promoting component of Hh signalling.

The chrondoprotective actions of a natural product are associated with the activation of IGF-1 production by human chondrocytes despite the presence of IL-1β

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Bobrowski Paul

2006-04-01

Full Text Available Abstract Background Cartilage loss is a hallmark of arthritis and follows activation of catabolic processes concomitant with a disruption of anabolic pathways like insulin-like growth factor 1 (IGF-1. We hypothesized that two natural products of South American origin, would limit cartilage degradation by respectively suppressing catabolism and activating local IGF-1 anabolic pathways. One extract, derived from cat's claw (Uncaria guianensis, vincaria®, is a well-described inhibitor of NF-κB. The other extract, derived from the vegetable Lepidium meyenii (RNI 249, possessed an uncertain mechanism of action but with defined ethnomedical applications for fertility and vitality. Methods Human cartilage samples were procured from surgical specimens with consent, and were evaluated either as explants or as primary chondrocytes prepared after enzymatic digestion of cartilage matrix. Assessments included IGF-1 gene expression, IGF-1 production (ELISA, cartilage matrix degradation and nitric oxide (NO production, under basal conditions and in the presence of IL-1β. Results RNI 249 enhanced basal IGF-1 mRNA levels in human chondrocytes by 2.7 fold, an effect that was further enhanced to 3.8 fold by co-administration with vincaria. Enhanced basal IGF-1 production by RNI 249 alone and together with vincaria, was confirmed in both explants and in primary chondrocytes (P Conclusion The identification of agents that activate the autocrine production of IGF-1 in cartilage, even in the face of suppressive pro-inflammatory, catabolic cytokines like IL-1β, represents a novel therapeutic approach to cartilage biology. Chondroprotection associated with prevention of the catabolic events and the potential for sustained anabolic activity with this natural product suggests that it holds significant promise in the treatment of debilitating joint diseases.

Roles of Chondrocytes in Endochondral Bone Formation and Fracture Repair

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Hinton, R.J.; Jing, Y.; Jing, J.; Feng, J.Q.

2016-01-01

The formation of the mandibular condylar cartilage (MCC) and its subchondral bone is an important but understudied topic in dental research. The current concept regarding endochondral bone formation postulates that most hypertrophic chondrocytes undergo programmed cell death prior to bone formation. Under this paradigm, the MCC and its underlying bone are thought to result from 2 closely linked but separate processes: chondrogenesis and osteogenesis. However, recent investigations using cell lineage tracing techniques have demonstrated that many, perhaps the majority, of bone cells are derived via direct transformation from chondrocytes. In this review, the authors will briefly discuss the history of this idea and describe recent studies that clearly demonstrate that the direct transformation of chondrocytes into bone cells is common in both long bone and mandibular condyle development and during bone fracture repair. The authors will also provide new evidence of a distinct difference in ossification orientation in the condylar ramus (1 ossification center) versus long bone ossification formation (2 ossification centers). Based on our recent findings and those of other laboratories, we propose a new model that contrasts the mode of bone formation in much of the mandibular ramus (chondrocyte-derived) with intramembranous bone formation of the mandibular body (non-chondrocyte-derived). PMID:27664203

Articular chondrocyte alignment in the rat after surgically induced osteoarthritis

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Takahashi, Hideaki; Tamaki, Hiroyuki; Yamamoto, Noriaki; Onishi, Hideaki

2017-01-01

[Purpose] Chondrocytes in articular cartilage are aligned as columns from the joint surface. Notably, loss of chondrocyte and abnormalities of differentiation factors give rise to osteoarthritis (OA). However, the relationship between chondrocyte alignment and OA progression remains unclear. This study was performed to investigate temporal alterations in surgically-induced OA rats. [Subjects and Methods] Thirteen-week-old Wistar rats (n=30) underwent destabilized medial meniscus surgery in their right knee and sham surgery in their left knee. Specimens (n=5) were collected at 0, 1, 2, 4 and 8 weeks after surgery. Histological analysis with Osteoarthritis Research Society International (OARSI) scores, cell density ratios, cell alignments and correlation between OARSI scores and cell density/alignment was performed. [Results] OARSI scores were significantly higher at 1, 2, 4 and 8 weeks in the DMM group than in the control. Cell density ratios were decreased significantly in the DMM group at 2, 4 and 8 weeks compared with the control. Chondrocyte alignment was decreased significantly in the DMM group at 4 and 8 weeks. There were negative correlations between OA severity and cell density / cell alignment. [Conclusion] The results suggest a relationship between chondrocyte alignment and cartilage homeostasis, which plays an important role in OA progression. PMID:28533592

Autologous chondrocyte implantation: superior biologic properties of hyaline cartilage repairs.

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Henderson, Ian; Lavigne, Patrick; Valenzuela, Herminio; Oakes, Barry

2007-02-01

Information regarding the quality of autologous chondrocyte implantation repair is needed to determine whether the current autologous chondrocyte implantation surgical technology and the subsequent biologic repair processes are capable of reliably forming durable hyaline or hyaline-like cartilage in vivo. We report and analyze the properties and qualities of autologous chondrocyte implantation repairs. We evaluated 66 autologous chondrocyte implantation repairs in 57 patients, 55 of whom had histology, indentometry, and International Cartilage Repair Society repair scoring at reoperation for mechanical symptoms or pain. International Knee Documentation Committee scores were used to address clinical outcome. Maximum stiffness, normalized stiffness, and International Cartilage Repair Society repair scoring were higher for hyaline articular cartilage repairs compared with fibrocartilage, with no difference in clinical outcome. Reoperations revealed 32 macroscopically abnormal repairs (Group B) and 23 knees with normal-looking repairs in which symptoms leading to arthroscopy were accounted for by other joint disorders (Group A). In Group A, 65% of repairs were either hyaline or hyaline-like cartilage compared with 28% in Group B. Autologous chondrocyte repairs composed of fibrocartilage showed more morphologic abnormalities and became symptomatic earlier than hyaline or hyaline-like cartilage repairs. The hyaline articular cartilage repairs had biomechanical properties comparable to surrounding cartilage and superior to those associated with fibrocartilage repairs.

Atf4 regulates chondrocyte proliferation and differentiation during endochondral ossification by activating Ihh transcription.

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Wang, Weiguang; Lian, Na; Li, Lingzhen; Moss, Heather E; Wang, Weixi; Perrien, Daniel S; Elefteriou, Florent; Yang, Xiangli

2009-12-01

Activating transcription factor 4 (Atf4) is a leucine-zipper-containing protein of the cAMP response element-binding protein (CREB) family. Ablation of Atf4 (Atf4(-/-)) in mice leads to severe skeletal defects, including delayed ossification and low bone mass, short stature and short limbs. Atf4 is expressed in proliferative and prehypertrophic growth plate chondrocytes, suggesting an autonomous function of Atf4 in chondrocytes during endochondral ossification. In Atf4(-/-) growth plate, the typical columnar structure of proliferative chondrocytes is disturbed. The proliferative zone is shortened, whereas the hypertrophic zone is transiently expanded. The expression of Indian hedgehog (Ihh) is markedly decreased, whereas the expression of other chondrocyte marker genes, such as type II collagen (Col2a1), PTH/PTHrP receptor (Pth1r) and type X collagen (Col10a1), is normal. Furthermore, forced expression of Atf4 in chondrocytes induces endogenous Ihh mRNA, and Atf4 directly binds to the Ihh promoter and activates its transcription. Supporting these findings, reactivation of Hh signaling pharmacologically in mouse limb explants corrects the Atf4(-/-) chondrocyte proliferation and short limb phenotypes. This study thus identifies Atf4 as a novel transcriptional activator of Ihh in chondrocytes that paces longitudinal bone growth by controlling growth plate chondrocyte proliferation and differentiation.

[Construction of porous hydroxyapatite (HA) block loaded with cultured chondrocytes].

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Yan, M; Dang, G

1999-07-01

To construct a kind of bone healing enhancing implant with cultured chondrocytes bound to hydroxyapatite (HA). Chondrocytes were obtained from the costicartilage of rat and were cultured on the porous HA blocks, 3 mm x 3 mm x 4 mm size, for three and seven days. Scanning electron micrograph was taken to show whether the cells grew outside and inside the pore of HA block. The cells cultured on tiny glass sheet for 2 days were used to prove where the cells come from by in situ hybridization technique with alpha1 (II) cDNA probe. Scanning electron micrographs showed that the pores of the HA surface and inside of the blocks are filled with cultured cells, especially the longer cultured block. The cells were chondrocytes confirmed by in situ hybridization. The porous HA can be used as cell cultured substrate and chondrocyte can adhere and proliferate inside the porous HA block.

Human articular chondrocytes secrete parathyroid hormone-related protein and inhibit hypertrophy of mesenchymal stem cells in coculture during chondrogenesis.

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Fischer, J; Dickhut, A; Rickert, M; Richter, W

2010-09-01

The use of bone marrow-derived mesenchymal stem cells (MSCs) has shown promise in cell-based cartilage regeneration. A yet-unsolved problem, however, is the unwanted up-regulation of markers of hypertrophy, such as alkaline phosphatase (AP) and type X collagen, during in vitro chondrogenesis and the formation of unstable calcifying cartilage at heterotopic sites. In contrast, articular chondrocytes produce stable, nonmineralizing cartilage. The aim of this study was to address whether coculture of MSCs with human articular chondrocytes (HACs) can suppress the undesired hypertrophy in differentiating MSCs. MSCs were differentiated in chondrogenic medium that had or had not been conditioned by parallel culture with HAC pellets, or MSCs were mixed in the same pellet with the HACs (1:1 or 1:2 ratio) and cultured for 6 weeks. Following in vitro differentiation, the pellets were transplanted into SCID mice. The gene expression ratio of COL10A1 to COL2A1 and of Indian hedgehog (IHH) to COL2A1 was significantly reduced by differentiation in HAC-conditioned medium, and less type X collagen protein was deposited relative to type II collagen. AP activity was significantly lower (P chondrogenesis. The main inhibitory effects seen with HAC-conditioned medium were reproducible by PTHrP supplementation of unconditioned medium. HAC-derived soluble factors and direct coculture are potent means of improving chondrogenesis and suppressing the hypertrophic development of MSCs. PTHrP is an important candidate soluble factor involved in this effect.

Conditional expression of constitutively active estrogen receptor α in chondrocytes impairs longitudinal bone growth in mice

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Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko; Horie-Inoue, Kuniko; Inoue, Satoshi

2012-01-01

Highlights: ► Conditional transgenic mice expressing constitutively active estrogen receptor α (caERα) in chondrocytes were developed. ► Expression of caERα in chondrocytes impaired longitudinal bone growth in mice. ► caERα affects chondrocyte proliferation and differentiation. ► This mouse model is useful for understanding the physiological role of ERαin vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caERα ColII , expressing constitutively active mutant estrogen receptor (ER) α in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caERα ColII mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caERα ColII mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caERα ColII mice. These results suggest that ERα is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

Human immunodeficiency virus type 1 enhancer-binding protein 3 is essential for the expression of asparagine-linked glycosylation 2 in the regulation of osteoblast and chondrocyte differentiation.

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Imamura, Katsuyuki; Maeda, Shingo; Kawamura, Ichiro; Matsuyama, Kanehiro; Shinohara, Naohiro; Yahiro, Yuhei; Nagano, Satoshi; Setoguchi, Takao; Yokouchi, Masahiro; Ishidou, Yasuhiro; Komiya, Setsuro

2014-04-04

Human immunodeficiency virus type 1 enhancer-binding protein 3 (Hivep3) suppresses osteoblast differentiation by inducing proteasomal degradation of the osteogenesis master regulator Runx2. In this study, we tested the possibility of cooperation of Hivep1, Hivep2, and Hivep3 in osteoblast and/or chondrocyte differentiation. Microarray analyses with ST-2 bone stroma cells demonstrated that expression of any known osteochondrogenesis-related genes was not commonly affected by the three Hivep siRNAs. Only Hivep3 siRNA promoted osteoblast differentiation in ST-2 cells, whereas all three siRNAs cooperatively suppressed differentiation in ATDC5 chondrocytes. We further used microarray analysis to identify genes commonly down-regulated in both MC3T3-E1 osteoblasts and ST-2 cells upon knockdown of Hivep3 and identified asparagine-linked glycosylation 2 (Alg2), which encodes a mannosyltransferase residing on the endoplasmic reticulum. The Hivep3 siRNA-mediated promotion of osteoblast differentiation was negated by forced Alg2 expression. Alg2 suppressed osteoblast differentiation and bone formation in cultured calvarial bone. Alg2 was immunoprecipitated with Runx2, whereas the combined transfection of Runx2 and Alg2 interfered with Runx2 nuclear localization, which resulted in suppression of Runx2 activity. Chondrocyte differentiation was promoted by Hivep3 overexpression, in concert with increased expression of Creb3l2, whose gene product is the endoplasmic reticulum stress transducer crucial for chondrogenesis. Alg2 silencing suppressed Creb3l2 expression and chondrogenesis of ATDC5 cells, whereas infection of Alg2-expressing virus promoted chondrocyte maturation in cultured cartilage rudiments. Thus, Alg2, as a downstream mediator of Hivep3, suppresses osteogenesis, whereas it promotes chondrogenesis. To our knowledge, this study is the first to link a mannosyltransferase gene to osteochondrogenesis.

Hyaluronan Protects Bovine Articular Chondrocytes against Cell Death Induced by Bupivacaine under Supraphysiologic Temperatures

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Liu, Sen; Zhang, Qing-Song; Hester, William; O’Brien, Michael J.; Savoie, Felix H.; You, Zongbing

2013-01-01

Background Bupivacaine and supraphysiologic temperature can independently reduce cell viability of articular chondrocytes. In combination these two deleterious factors could further impair cell viability. Hypothesis Hyaluronan may protect chondrocytes from death induced by bupivacaine at supraphysiologic temperatures. Study Design Controlled laboratory study. Methods Bovine articular chondrocytes were treated with hyaluronan at physiologic (37°C) and supraphysiologic temperatures (45°C and 50°C) for one hour, and then exposed to bupivacaine for one hour at room temperature. Cell viability was assessed at three time points: immediately after treatment, six hours later, and twenty-four hours later using flow cytometry and fluorescence microscopy. The effects of hyaluronan on the levels of sulfated glycosaminoglycan in the chondrocytes were determined using Alcian blue staining. Results (1) Bupivacaine alone did not induce noticeable chondrocyte death at 37°C; (2) bupivacaine and temperature synergistically increased chondrocyte death, that is, when the chondrocytes were conditioned to 45°C and 50°C, 0.25% and 0.5% bupivacaine increased the cell death rate by 131% to 383% in comparison to the phosphate-buffered saline control group; and, (3) addition of hyaluronan reduced chondrocyte death rates to approximately 14% and 25% at 45°C and 50°C, respectively. Hyaluronan’s protective effects were still observed at six and twenty-four hours after bupivacaine treatment at 45°C. However, at 50°C, hyaluronan delayed but did not prevent the cell death caused by bupivacaine. One-hour treatment with hyaluronan significantly increased sulfated glycosaminoglycan levels in the chondrocytes. Conclusions Bupivacaine and supraphysiologic temperature synergistically increase chondrocyte death and hyaluronan may protect articular chondrocytes from death caused by bupivacaine. Clinical Relevance This study provides a rationale to perform pre-clinical and clinical studies to

Chondroprotective effects of a proanthocyanidin rich Amazonian genonutrient reflects direct inhibition of matrix metalloproteinases and upregulation of IGF-1 production by human chondrocytes

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Gupta Kalpana

2007-08-01

Full Text Available Abstract Background The Amazonian medicinal plant Sangre de grado (Croton palanostigma has traditional applications for the treatment of wound healing and inflammation. We sought to characterize two extracts (progrado and zangrado in terms of safety and oligomeric proanthocyanidin chain length. Additionally progrado was evaluated for antioxidant activity and possible chondroprotective actions. Methods Acute oral safety and toxicity was tested in rats according under OECD protocol number 420. The profile of proanthocyanidin oligomers was determined by HPLC and progrado's antioxidant activity quantified by the ORAC, NORAC and HORAC assays. Human cartilage explants, obtained from surgical specimens, were used to assess chondroproteciton with activity related to direct inhibitory effects on human matrix metalloproteinase (MMP, gelatinolytic activity using synovial fluid and chondrocytes activated with IL-1β (10 ng/ml. Additionally, progrado (2–10 μg/ml was tested for its ability to maintain optimal IGF-1 transcription and translation in cartilage explants and cultured chondrocytes. Results Both progrado and zangrado at doses up to 2000 mg/kg (po displayed no evidence of toxicity. Oligomeric proanthocyanidin content was high for both progrado (158 mg/kg and zangrado (124 mg/kg, with zangrado almost entirely composed of short oligomers ( Conclusion Progrado has a promising safety profile, significant chondroprotective and antioxidant actions, directly inhibits MMP activity and promotes the production of the cartilage repair factor, IGF-1. This suggests that progrado may offer therapeutic benefits in joint health, wound healing and inflammation.

Effects of intermittent versus continuous parathyroid hormone administration on condylar chondrocyte proliferation and differentiation

International Nuclear Information System (INIS)

Liu, Qi; Wan, Qilong; Yang, Rongtao; Zhou, Haihua; Li, Zubing

2012-01-01

Highlights: ► Different PTH administration exerts different effects on condylar chondrocyte. ► Intermittent PTH administration suppresses condylar chondrocyte proliferation. ► Continuous PTH administration maintains condylar chondrocyte proliferating. ► Intermittent PTH administration enhances condylar chondrocyte differentiation. -- Abstract: Endochondral ossification is a complex process involving chondrogenesis and osteogenesis regulated by many hormones and growth factors. Parathyroid hormone (PTH), one of the key hormones regulating bone metabolism, promotes osteoblast differentiation and osteogenesis by intermittent administration, whereas continuous PTH administration inhibits bone formation. However, the effects of PTH on chondrocyte proliferation and differentiation are still unclear. In this study, intermittent PTH administration presented enhanced effects on condylar chondrocyte differentiation and bone formation, as demonstrated by increased mineral nodule formation and alkaline phosphatase (ALP) activity, up-regulated runt-related transcription factor 2 (RUNX2), ALP, collagen type X (COL10a1), collagen type I (COL1a1), osteocalcin (OCN), bone sialoprotein (BSP), bone morphogenetic protein 2 (BMP2) and osterix (OSX) mRNA and/or protein expression. On the contrary, continuous PTH administration promoted condylar chondrocyte proliferation and suppressed its differentiation, as demonstrated by up-regulated collagen type II (COL2a1) mRNA expression, reduced mineral nodule formation and down-regulated expression of the mRNAs and/or proteins mentioned above. Our data suggest that PTH can regulate condylar chondrocyte proliferation and differentiation, depending on the type of PTH administration. These results provide new insight into the effects of PTH on condylar chondrocytes and new evidence for using local PTH administration to cure mandibular asymmetry.

Modulation of Hyaluronan Synthesis by the Interaction between Mesenchymal Stem Cells and Osteoarthritic Chondrocytes

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Eliane Antonioli

2015-01-01

Full Text Available Bone marrow mesenchymal stem cells (BM-MSCs are considered a good source for cellular therapy in cartilage repair. But, their potential to repair the extracellular matrix, in an osteoarthritic environment, is still controversial. In osteoarthritis (OA, anti-inflammatory action and extracellular matrix production are important steps for cartilage healing. This study examined the interaction of BM-MSC and OA-chondrocyte on the production of hyaluronan and inflammatory cytokines in a Transwell system. We compared cocultured BM-MSCs and OA-chondrocytes with the individually cultured controls (monocultures. There was a decrease in BM-MSCs cell count in coculture with OA-chondrocytes when compared to BM-MSCs alone. In monoculture, BM-MSCs produced higher amounts of hyaluronan than OA-chondrocytes and coculture of BM-MSCs with OA-chondrocytes increased hyaluronan production per cell. Hyaluronan synthase-1 mRNA expression was upregulated in BM-MSCs after coculture with OA-chondrocytes, whereas hyaluronidase-1 was downregulated. After coculture, lower IL-6 levels were detected in BM-MSCs compared with OA-chondrocytes. These results indicate that, in response to coculture with OA-chondrocytes, BM-MSCs change their behavior by increasing production of hyaluronan and decreasing inflammatory cytokines. Our results indicate that BM-MSCs per se could be a potential tool for OA regenerative therapy, exerting short-term effects on the local microenvironment even when cell:cell contact is not occurring.

Inhibition of Chondrocyte Hypertrophy of Osteoarthritis by Disruptor Peptide

Science.gov (United States)

2017-07-01

with PTHR and inhibits the pathogenic beta-catenin- mediated PTHR signaling switch. In Aim 2, we will define the role of disruptor peptide in...confirmed that disruptor peptide conjugated to penetratin can enter cells. Importantly, disruptor peptide can reverse the beta-catenin- mediated PTH... mediated PTHR signaling switch in chondrocytes. Mouse primary chondrocytes express both β-catenin and PTHR. Our data showed that Pen-dis- pep

Stable subcutaneous cartilage regeneration of bone marrow stromal cells directed by chondrocyte sheet.

Science.gov (United States)

Li, Dan; Zhu, Lian; Liu, Yu; Yin, Zongqi; Liu, Yi; Liu, Fangjun; He, Aijuan; Feng, Shaoqing; Zhang, Yixin; Zhang, Zhiyong; Zhang, Wenjie; Liu, Wei; Cao, Yilin; Zhou, Guangdong

2017-05-01

In vivo niche plays an important role in regulating differentiation fate of stem cells. Due to lack of proper chondrogenic niche, stable cartilage regeneration of bone marrow stromal cells (BMSCs) in subcutaneous environments is always a great challenge. This study explored the feasibility that chondrocyte sheet created chondrogenic niche retained chondrogenic phenotype of BMSC engineered cartilage (BEC) in subcutaneous environments. Porcine BMSCs were seeded into biodegradable scaffolds followed by 4weeks of chondrogenic induction in vitro to form BEC, which were wrapped with chondrocyte sheets (Sheet group), acellular small intestinal submucosa (SIS, SIS group), or nothing (Blank group) respectively and then implanted subcutaneously into nude mice to trace the maintenance of chondrogenic phenotype. The results showed that all the constructs in Sheet group displayed typical cartilaginous features with abundant lacunae and cartilage specific matrices deposition. These samples became more mature with prolonged in vivo implantation, and few signs of ossification were observed at all time points except for one sample that had not been wrapped completely. Cell labeling results in Sheet group further revealed that the implanted BEC directly participated in cartilage formation. Samples in both SIS and Blank groups mainly showed ossified tissue at all time points with partial fibrogenesis in a few samples. These results suggested that chondrocyte sheet could create a chondrogenic niche for retaining chondrogenic phenotype of BEC in subcutaneous environment and thus provide a novel research model for stable ectopic cartilage regeneration based on stem cells. In vivo niche plays an important role in directing differentiation fate of stem cells. Due to lack of proper chondrogenic niche, stable cartilage regeneration of bone marrow stromal cells (BMSCs) in subcutaneous environments is always a great challenge. The current study demonstrated that chondrocyte sheet generated by

Promoted Chondrogenesis of Cocultured Chondrocytes and Mesenchymal Stem Cells under Hypoxia Using In-situ Forming Degradable Hydrogel Scaffolds

NARCIS (Netherlands)

Huang, Xiaobin; Hou, Yong; Zhong, Leilei; Huang, Dechun; Qian, Hongliang; Karperien, Marcel; Chen, Wei

2018-01-01

We investigated the effects of different oxygen tension (21% and 2.5% O2) on the chondrogenesis of different cell systems cultured in pH-degradable PVA hydrogels, including human articular chondrocytes (hACs), human mesenchymal stem cells (hMSCs), and their cocultures with a hAC/hMSC ratio of 20/80.

Study of differential properties of fibrochondrocytes and hyaline chondrocytes in growing rabbits.

Science.gov (United States)

Huang, L; Li, M; Li, H; Yang, C; Cai, X

2015-02-01

We aimed to build a culture model of chondrocytes in vitro, and to study the differential properties between fibrochondrocytes and hyaline chondrocytes. Histological sections were stained with haematoxylin and eosin so that we could analyse the histological structure of the fibrocartilage and hyaline cartilage. Condylar fibrochondrocytes and femoral hyaline chondrocytes were cultured from four, 4-week-old, New Zealand white rabbits. The production of COL2A1, COL1OA1, SOX9 and aggrecan was detected by real time-q polymerase chain reaction (RT-qPCR) and immunoblotting and the differences between them were compared statistically. Histological structures obviously differed between fibrocartilage and hyaline cartilage. COL2A1 and SOX9 were highly expressed within cell passage 2 (P2) of both fibrochondrocytes and hyaline chondrocytes, and reduced significantly after cell passage 4 (P4). The mRNA expressions of COL2A1 (p=0.05), COL10A1 (p=0.04), SOX9 (p=0.03), and aggrecan (p=0.04) were significantly higher in hyaline chondrocytes than in fibrochondrocytes, whereas the expression of COL1A1 (p=0.02) was the opposite. Immunoblotting showed similar results. We have built a simple and effective culture model of chondrocytes in vitro, and the P2 of chondrocytes is recommended for further studies. Condylar fibrocartilage and femoral hyaline cartilage have unique biological properties, and the regulatory mechanisms of endochondral ossification for the condyle should be studied independently in the future. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

In-vitro interactions of human chondrocytes and mesenchymal stem cells, and of mouse macrophages with phospholipid-covered metallic implant materials

Directory of Open Access Journals (Sweden)

R Willumeit

2007-03-01

Full Text Available Phospholipid-coatings on metallic implant surfaces were evaluated in terms of adhesion, proliferation and matrix production of skeletal cells, and of macrophage stimulation. The working hypothesis is that mimicking a model biomembrane by phospholipids on surfaces to which cells adhere, the surface recognition by surrounding cells is altered. In this study, 1 mirror-like polished Ti-6Al-7Nb and 2 porous Ti-6Al-4V specimens were covered with the phospholipids POPE (palmitoyl-oleoyl phosphatidyl-ethanolamine and POPC (palmitoyl-oleoyl phosphatidyl-choline, and the interactions of a human articular chondrocytes (HAC, b human mesenchymal stem cells (HMSC, and c mouse macrophages (RAW 264.7 were tested in vitro. On POPE-covered polished surfaces adherence of HAC (42% of seeded cells after 2 hrs and metabolic activity (MTT after 3 days were reduced, while on porous surfaces 99% HAC adhered, and metabolic activity was significantly increased, compared to respective native surfaces. On both POPE-covered surfaces the chondrocyte phenotype was present. After 3 weeks of chondrogenic differentiation, cartilage matrix production (measuring chondroitin sulphate per HAC number was significantly increased by about 30% on both POPE-covered metallic surfaces. On both POPC-covered surfaces nearly no adhering and surviving HAC were found. HMSC grown on POPE-covered porous substrates showed osteogenic differentiation by improved osteopontin and collagen I expression in RT-PCR, and osteocalcin fluorescence and bone nodule formation was only detectable on POPE-covered porous surfaces. In contrast to POPC and other phospholipids used as positive controls, POPE did not stimulate the NO production in mouse macrophage cultures. We therefore conclude that a phospholipid coating by POPE shows potential as surface modification for metallic implant materials.

Effects of intermittent versus continuous parathyroid hormone administration on condylar chondrocyte proliferation and differentiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Qi; Wan, Qilong; Yang, Rongtao; Zhou, Haihua [The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079 (China); Li, Zubing, E-mail: lizubing0827@163.com [The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079 (China); Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079 (China)

2012-07-20

Highlights: Black-Right-Pointing-Pointer Different PTH administration exerts different effects on condylar chondrocyte. Black-Right-Pointing-Pointer Intermittent PTH administration suppresses condylar chondrocyte proliferation. Black-Right-Pointing-Pointer Continuous PTH administration maintains condylar chondrocyte proliferating. Black-Right-Pointing-Pointer Intermittent PTH administration enhances condylar chondrocyte differentiation. -- Abstract: Endochondral ossification is a complex process involving chondrogenesis and osteogenesis regulated by many hormones and growth factors. Parathyroid hormone (PTH), one of the key hormones regulating bone metabolism, promotes osteoblast differentiation and osteogenesis by intermittent administration, whereas continuous PTH administration inhibits bone formation. However, the effects of PTH on chondrocyte proliferation and differentiation are still unclear. In this study, intermittent PTH administration presented enhanced effects on condylar chondrocyte differentiation and bone formation, as demonstrated by increased mineral nodule formation and alkaline phosphatase (ALP) activity, up-regulated runt-related transcription factor 2 (RUNX2), ALP, collagen type X (COL10a1), collagen type I (COL1a1), osteocalcin (OCN), bone sialoprotein (BSP), bone morphogenetic protein 2 (BMP2) and osterix (OSX) mRNA and/or protein expression. On the contrary, continuous PTH administration promoted condylar chondrocyte proliferation and suppressed its differentiation, as demonstrated by up-regulated collagen type II (COL2a1) mRNA expression, reduced mineral nodule formation and down-regulated expression of the mRNAs and/or proteins mentioned above. Our data suggest that PTH can regulate condylar chondrocyte proliferation and differentiation, depending on the type of PTH administration. These results provide new insight into the effects of PTH on condylar chondrocytes and new evidence for using local PTH administration to cure mandibular

Differentiation of chondrocytes and scleroblasts during dorsal fin skeletogenesis in flounder larvae.

Science.gov (United States)

Suzuki, Tohru; Haga, Yutaka; Takeuchi, Toshio; Uji, Susumu; Hashimoto, Hisashi; Kurokawa, Tadahide

2003-01-01

In teleosts, the embryonic fin fold consists of a peridermis, an underlying epidermis and a small number of mesenchymal cells. Beginning from such a simple structure, the fin skeletons, including the proximal and distal radials and lepidotrichia (finrays), develop in the dorsal fin fold at the larval stage. Their process of skeletogenesis and embryonic origin are unclear. Using flounder larvae, we report the differentiation process for chondrocytes and scleroblasts prior to fin skeletogenesis and the effects of retinoic acid (RA) on it. In early larvae, the mesenchymal cells grow between the epidermis and spinal cord to form a line of periodical condensations, which are proximal radial primordia, to produce chondrocytes. The prescleroblasts, which ossify the proximal radial cartilages, differentiate in the mesenchymal cells remaining between the cartilages. Then, mesenchymal condensations occur between the distal ends of the proximal radials, forming distal radial primordia, to produce chondrocytes. Simultaneously, condensations occur between the distal radial primordia and peridermis, which are lepidotrichia primordia, to produce prescleroblasts. Exogenous RA specifically inhibits the mesenchymal condensation prior to the proximal radial formation together with the down-regulation of sonic hedgehog (shh) and patched (pta) expression, resulting in the loss of proximal radials. Thus, it was indicated that differentiation of the precursor cells of radials and lepidotrichia begins in the proximal part of the fin fold and that the initial mesenchymal condensation prior to the proximal radial formation is highly susceptible to the effects of RA. Lepidotrichia formation does not occur where proximal radials are absent, indicating that lepidotrichia differentiation requires interaction with the radial cartilages. To examine the suggestion that neural crest cells contribute to the medial fin skeletons, we localized the HNK-1 positive cells in flounder embryos and slug and

THE ACTIVATION OF MATRIX METALLOPROTEINASES AND CHONDROCYTE DIFFERENTIATION, WHICH ACCOMPANIES THE INDUCTION OF COLLAGEN DECOMPOSITION UNDER THE ACTION OF COLLAGEN PEPTIDE IN THE CARTILAGE OFHEALTHY INDIVIDUALS

Directory of Open Access Journals (Sweden)

Elena Vasil'evna Chetina

2010-01-01

Conclusion. This study has shown that the induction of collagenase activity by CB12-2 in the human articular cartilage chondrocytes is attended by terminal differentiation/hypertrophy of these cells. The terminal differentiation of chondrocytes may be one of the mechanisms of chondrolysis in osteoarthrosis since it naturally occurs not only in endochondrial ossification, but also in the development of pathology.

TrxR2 deficiencies promote chondrogenic differentiation and induce apoptosis of chondrocytes through mitochondrial reactive oxygen species

International Nuclear Information System (INIS)

Yan, Jidong; Xu, Jing; Fei, Yao; Jiang, Congshan; Zhu, Wenhua; Han, Yan; Lu, Shemin

2016-01-01

mitochondrial ROS which could stimulate cartilage ECM synthesis that offer novel insights for development of therapeutic agent to prevent cartilage degeneration in human disease. - Highlights: • TrxR2 deficiencies enhance chondrogenic differentiation. • TrxR2 deficiencies stimulate chondrocyte proliferation. • TrxR2 deficiencies induce chondrocyte apoptosis. • TrxR2 deficiencies increase emission of mitochondrial ROS. • Mitochondrial ROS regulate chondrocyte proliferation, differentiation, and apoptosis.

TrxR2 deficiencies promote chondrogenic differentiation and induce apoptosis of chondrocytes through mitochondrial reactive oxygen species

Energy Technology Data Exchange (ETDEWEB)

Yan, Jidong [Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Xu, Jing [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Fei, Yao [College of Life Sciences, Northwest University, Xi’an, Shaanxi Province 710069 (China); Jiang, Congshan; Zhu, Wenhua; Han, Yan [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Lu, Shemin, E-mail: lushemin@xjtu.edu.cn [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education of China (China)

2016-05-15

mitochondrial ROS which could stimulate cartilage ECM synthesis that offer novel insights for development of therapeutic agent to prevent cartilage degeneration in human disease. - Highlights: • TrxR2 deficiencies enhance chondrogenic differentiation. • TrxR2 deficiencies stimulate chondrocyte proliferation. • TrxR2 deficiencies induce chondrocyte apoptosis. • TrxR2 deficiencies increase emission of mitochondrial ROS. • Mitochondrial ROS regulate chondrocyte proliferation, differentiation, and apoptosis.

Smad6/Smurf1 overexpression in cartilage delays chondrocyte hypertrophy and causes dwarfism with osteopenia

Science.gov (United States)

Horiki, Mitsuru; Imamura, Takeshi; Okamoto, Mina; Hayashi, Makoto; Murai, Junko; Myoui, Akira; Ochi, Takahiro; Miyazono, Kohei; Yoshikawa, Hideki; Tsumaki, Noriyuki

2004-01-01

Biochemical experiments have shown that Smad6 and Smad ubiquitin regulatory factor 1 (Smurf1) block the signal transduction of bone morphogenetic proteins (BMPs). However, their in vivo functions are largely unknown. Here, we generated transgenic mice overexpressing Smad6 in chondrocytes. Smad6 transgenic mice showed postnatal dwarfism with osteopenia and inhibition of Smad1/5/8 phosphorylation in chondrocytes. Endochondral ossification during development in these mice was associated with almost normal chondrocyte proliferation, significantly delayed chondrocyte hypertrophy, and thin trabecular bone. The reduced population of hypertrophic chondrocytes after birth seemed to be related to impaired bone growth and formation. Organ culture of cartilage rudiments showed that chondrocyte hypertrophy induced by BMP2 was inhibited in cartilage prepared from Smad6 transgenic mice. We then generated transgenic mice overexpressing Smurf1 in chondrocytes. Abnormalities were undetectable in Smurf1 transgenic mice. Mating Smad6 and Smurf1 transgenic mice produced double-transgenic pups with more delayed endochondral ossification than Smad6 transgenic mice. These results provided evidence that Smurf1 supports Smad6 function in vivo. PMID:15123739

Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

Energy Technology Data Exchange (ETDEWEB)

Ikeda, Kazuhiro [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Tsukui, Tohru [Experimental Animal Laboratory, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Imazawa, Yukiko; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan)

2012-09-07

Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively active mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

Cyclic Equibiaxial Tensile Strain Alters Gene Expression of Chondrocytes via Histone Deacetylase 4 Shuttling.

Directory of Open Access Journals (Sweden)

Chongwei Chen

Full Text Available This paper aims to investigate whether equibiaxial tensile strain alters chondrocyte gene expression via controlling subcellular localization of histone deacetylase 4 (HDAC4.Murine chondrocytes transfected with GFP-HDAC4 were subjected to 3 h cyclic equibiaxial tensile strain (CTS, 6% strain at 0.25 Hz by a Flexcell® FX-5000™ Tension System. Fluorescence microscope and western blot were used to observe subcellular location of HDAC4. The gene expression was analyzed by real-time RT-PCR. The concentration of Glycosaminoglycans in culture medium was quantified by bimethylmethylene blue dye; Collagen II protein was evaluated by western blot. Cells phenotype was identified by immunohistochemistry. Cell viability was evaluated by live-dead cell detect kit. Okadaic acid, an inhibitor of HDAC4 nuclear relocation, was used to further validate whether HDAC4 nuclear relocation plays a role in gene expression in response to tension stimulation.87.5% of HDAC4 was located in the cytoplasm in chondrocytes under no loading condition, but it was relocated to the nucleus after CTS. RT-PCR analysis showed that levels of mRNA for aggrecan, collagen II, LK1 and SOX9 were all increased in chondrocytes subjected to CTS as compared to no loading control chondrocytes; in contrast, the levels of type X collagen, MMP-13, IHH and Runx2 gene expression were decreased in the chondrocytes subjected to CTS as compared to control chondrocytes. Meanwhile, CTS contributed to elevation of glycosaminoglycans and collagen II protein, but did not change collagen I production. When Okadaic acid blocked HDAC4 relocation from the cytoplasm to nucleus, the changes of the chondrocytes induced by CTS were abrogated. There was no chondrocyte dead detected in this study in response to CTS.CTS is able to induce HDAC4 relocation from cytoplasm to nucleus. Thus, CTS alters chondrocytes gene expression in association with the relocation of HDAC4 induced by CTS.

The role of autologous chondrocyte implantation in the treatment of symptomatic chondromalacia patellae.

Science.gov (United States)

Macmull, Simon; Jaiswal, Parag K; Bentley, George; Skinner, John A; Carrington, Richard W J; Briggs, Tim W R

2012-07-01

Chondromalacia patella is a distinct clinical entity of abnormal softening of the articular cartilage of the patella, which results in chronic retropatellar pain. Its aetiology is still unclear but the process is thought to be a due to trauma to superficial chondrocytes resulting in a proteolytic enzymic breakdown of the matrix. Our aim was to assess the effectiveness of autologous chondrocyte implantation on patients with a proven symptomatic retropatellar lesion who had at least one failed conventional marrow-stimulating therapy. We performed chondrocyte implantation on 48 patients: 25 received autologous chondrocyte implantation with a type I/III membrane (ACI-C) method (Geistlich Biomaterials, Wolhusen, Switzerland), and 23 received the Matrix-assisted Chondrocyte Implantation (MACI) technique (Genzyme, Kastrup, Denmark). Over a mean follow-up period of 40.3 months, there was a statistically significant improvement in subjective pain scoring using the visual analogue scale (VAS) and objective functional scores using the Modified Cincinnati Rating System (MCS) in both groups. Chondromalacia patellae lesions responded well to chondrocyte implantation. Better results occurred with MACI than with ACI-C. Excellent and good results were achieved in 40% of ACI-C patients and 57% of MACI patients, but success of chondrocyte implantation was greater with medial/odd-facet lesions. Given that the MACI procedure is technically easier and less time consuming, we consider it to be useful for treating patients with symptomatic chondral defects secondary to chondromalacia patellae.

Centrifugation assay for measuring adhesion of serially passaged bovine chondrocytes to polystyrene surfaces.

Science.gov (United States)

Kaplan, David S; Hitchins, Victoria M; Vegella, Thomas J; Malinauskas, Richard A; Ferlin, Kimberly M; Fisher, John P; Frondoza, Carmelita G

2012-07-01

A major obstacle in chondrocyte-based therapy for cartilage repair is the limited availability of cells that maintain their original phenotype. Propagation of chondrocytes as monolayer cultures on polystyrene surfaces is used extensively for amplifying cell numbers. However, chondrocytes undergo a phenotypic shift when propagated in this manner and display characteristics of more adherent fibroblastic cells. Little information is available about the effect of this phenotypic shift on cellular adhesion properties. We evaluated changes in adhesion property as bovine chondrocytes were serially propagated up to five passages in monolayer culture using a centrifugation cell adhesion assay, which was based on counting of cells before and after being exposed to centrifugal dislodgement forces of 120 and 350 g. Chondrocytes proliferated well in a monolayer culture with doubling times of 2-3 days, but they appeared more fibroblastic and exhibited elongated cell morphology with continued passage. The centrifugation cell adhesion assay showed that chondrocytes became more adhesive with passage as the percentage of adherent cells after centrifugation increased and was not statistically different from the adhesion of the fibroblast cell line, L929, starting at passage 3. This increased adhesiveness correlated with a shift to a fibroblastic morphology and increased collagen I mRNA expression starting at passage 2. Our findings indicate that the centrifugation cell adhesion assay may serve as a reproducible tool to track alterations in chondrocyte phenotype during their extended propagation in culture.

RAGE, receptor of advanced glycation endoproducts, negatively regulates chondrocytes differentiation.

Directory of Open Access Journals (Sweden)

Tatsuya Kosaka

Full Text Available RAGE, receptor for advanced glycation endoproducts (AGE, has been characterized as an activator of osteoclastgenesis. However, whether RAGE directly regulates chondrocyte proliferation and differentiation is unclear. Here, we show that RAGE has an inhibitory role in chondrocyte differentiation. RAGE expression was observed in chondrocytes from the prehypertrophic to hypertrophic regions. In cultured cells, overexpression of RAGE or dominant-negative-RAGE (DN-RAGE demonstrated that RAGE inhibited cartilaginous matrix production, while DN-RAGE promoted production. Additionally, RAGE regulated Ihh and Col10a1 negatively but upregulated PTHrP receptor. Ihh promoter analysis and real-time PCR analysis suggested that downregulation of Cdxs was the key for RAGE-induced inhibition of chondrocyte differentiation. Overexpression of the NF-κB inhibitor I-κB-SR inhibited RAGE-induced NF-κB activation, but did not influence inhibition of cartilaginous matrix production by RAGE. The inhibitory action of RAGE was restored by the Rho family GTPases inhibitor Toxin B. Furthermore, inhibitory action on Ihh, Col10a1 and Cdxs was reproduced by constitutively active forms, L63RhoA, L61Rac, and L61Cdc42, but not by I-κB-SR. Cdx1 induced Ihh and Col10a1 expressions and directly interacted with Ihh promoter. Retinoic acid (RA partially rescued the inhibitory action of RAGE. These data combined suggests that RAGE negatively regulates chondrocyte differentiation at the prehypertrophic stage by modulating NF-κB-independent and Rho family GTPases-dependent mechanisms.

Rabbit articular cartilage defects treated by allogenic chondrocyte transplantation

OpenAIRE

Boopalan, P. R. J. V. C.; Sathishkumar, Solomon; Kumar, Senthil; Chittaranjan, Samuel

2006-01-01

Articular cartilage defects have a poor capacity for repair. Most of the current treatment options result in the formation of fibro-cartilage, which is functionally inferior to normal hyaline articular cartilage. We studied the effectiveness of allogenic chondrocyte transplantation for focal articular cartilage defects in rabbits. Chondrocytes were cultured in vitro from cartilage harvested from the knee joints of a New Zealand White rabbit. A 3 mm defect was created in the articular cartilag...

Msx2 Stimulates Chondrocyte Maturation by Controlling Ihh Expression*

OpenAIRE

Amano, Katsuhiko; Ichida, Fumitaka; Sugita, Atsushi; Hata, Kenji; Wada, Masahiro; Takigawa, Yoko; Nakanishi, Masako; Kogo, Mikihiko; Nishimura, Riko; Yoneda, Toshiyuki

2008-01-01

Several studies indicated that a homeobox gene, Msx2, is implicated in regulation of skeletal development by controlling enchondral ossification as well as membranous ossification. However, the molecular basis by which Msx2 conducts chondrogenesis is currently unclear. In this study, we examined the role of Msx2 in chondrocyte differentiation using mouse primary chondrocytes and embryonic metatarsal explants. Treatment with BMP2 up-regulated the expression of Msx2 mRNA...

Beta1 integrins regulate chondrocyte rotation, G1 progression, and cytokinesis

DEFF Research Database (Denmark)

Aszodi, Attila; Hunziker, Ernst B; Brakebusch, Cord

2003-01-01

Beta1 integrins are highly expressed on chondrocytes, where they mediate adhesion to cartilage matrix proteins. To assess the functions of beta1 integrin during skeletogenesis, we inactivated the beta1 integrin gene in chondrocytes. We show here that these mutant mice develop a chondrodysplasia...... of various severity. beta1-deficient chondrocytes had an abnormal shape and failed to arrange into columns in the growth plate. This is caused by a lack of motility, which is in turn caused by a loss of adhesion to collagen type II, reduced binding to and impaired spreading on fibronectin, and an abnormal F......-actin organization. In addition, mutant chondrocytes show decreased proliferation caused by a defect in G1/S transition and cytokinesis. The G1/S defect is, at least partially, caused by overexpression of Fgfr3, nuclear translocation of Stat1/Stat5a, and up-regulation of the cell cycle inhibitors p16 and p21...

Histone Deacetylase 3 Suppresses Erk Phosphorylation and Matrix Metalloproteinase (Mmp)-13 Activity in Chondrocytes

Science.gov (United States)

Carpio, Lomeli R.; Bradley, Elizabeth W.; Westendorf, Jennifer J.

2017-01-01

Histone deacetylase inhibitors are emerging therapies for many diseases including cancers and neurological disorders; however, these drugs are teratogens to the developing skeleton. Hdac3 is essential for proper endochondral ossification as its deletion in chondrocytes increases cytokine signaling and the expression of matrix remodeling enzymes. Here we explored the mechanism by which Hdac3 controls Mmp13 expression in chondrocytes. In Hdac3-depleted chondrocytes, Erk1/2 as well as its downstream substrate, Runx2, were hyperphosphorylated as a result of decreased expression and activity of the Erk1/2 specific phosphatase, Dusp6. Erk1/2 kinase inhibitors and Dusp6 adenoviruses reduced Mmp13 expression and partially rescued matrix production in Hdac3-deficient chondrocytes. Postnatal chondrocyte-specific deletion of Hdac3 with an inducible Col2a1-Cre caused premature production of pErk1/2 and Mmp13 in the growth plate. Thus, Hdac3 controls the temporal and spatial expression of tissue-remodeling genes in chondrocytes to ensure proper endochondral ossification during development. PMID:27662443

IGF1 regulates RUNX1 expression via IRS1/2: Implications for antler chondrocyte differentiation

OpenAIRE

Yang, Zhan-Qing; Zhang, Hong-Liang; Duan, Cui-Cui; Geng, Shuang; Wang, Kai; Yu, Hai-Fan; Yue, Zhan-Peng; Guo, Bin

2017-01-01

Although IGF1 is important for the proliferation and differentiation of chondrocytes, its underlying molecular mechanism is still unknown. Here we addressed the physiologic function of IGF1 in antler cartilage and explored the interplay of IGF1, IRS1/2 and RUNX1 in chondrocyte differentiation. The results showed that IGF1 was highly expressed in antler chondrocytes. Exogenous rIGF1 could increase the proliferation of chondrocytes and cell proportion in the S phase, whereas IGF1R inhibitor PQ4...

Normal age-related viscoelastic properties of chondrons and chondrocytes isolated from rabbit knee

Institute of Scientific and Technical Information of China (English)

DUAN Wang-ping; SUN Zhen-wei; LI Qi; LI Chun-jiang; WANG Li; CHEN Wei-yi; Jennifer Tickner; ZHENG Ming-hao; WEI Xiao-chun

2012-01-01

Background The mechanical microenvironment of the chondrocytes plays an important role in cartilage homeostasis and in the health of the joint.The pericellular matrix,cellular membrane of the chondrocytes,and their cytoskeletal structures are key elements in the mechanical environment.The aims of this study are to measure the viscoelastic properties of isolated chondrons and chondrocytes from rabbit knee cartilage using micropipette aspiration and to determine the effect of aging on these properties.Methods Three age groups of rabbit knees were evaluated:(1) young (2 months,n=10);(2) adult (8 months,n=10);and (3) old (31 months,n=10).Chondrocytes were isolated from the right knee cartilage and chondrons were isolated from left knees using enzymatic methods.Micropipette aspiration combined with a standard linear viscoelastic solid model was used to quantify changes in the viscoelastic properties of chondrons and chondrocytes within 2 hours of isolation.The morphology and structure of isolated chondrons were evaluated by optical microscope using hematoxylin and eosin staining and collagen-6 immunofluorescence staining.Results In response to an applied constant 0.3-0.4 kPa of negative pressure,all chondrocytes exhibited standard linear viscoelastic solid properties.Model predictions of the creep data showed that the average equilibrium modulus (E∞),instantaneous modulus (E0).and apparent viscosity (μ) of old chondrocytes was significantly lower than the young and adult chondrocytes (P＜0.001);however,no difference was found between young and adult chondrocytes (P＞0.05).The adult and old chondrons generally possessed a thicker pericellular matrix (PCM) with more enclosed cells.The young and adult chondrons exhibited the same viscoelastic creep behavior under a greater applied pressure (1.0-1.1kPa) without the deformation seen in the old chondrons.The viscoelastic properties (E∞,E0,and u) of young and adult chondrons were significantly greater than that observed

Pronounced biomaterial dependency in cartilage regeneration using nonexpanded compared with expanded chondrocytes

NARCIS (Netherlands)

Tsuchida, A.I.; Bekkers, J.E.J.; Beekhuizen, M.; Vonk, L.A.; Dhert, W.J.A.; Saris, Daniël B.F.; Creemers, L.B.

2013-01-01

We aimed to investigate freshly isolated compared with culture-expanded chondrocytes with respect to early regenerative response, cytokine production and cartilage formation in response to four commonly used biomaterials. Materials & methods: Chondrocytes were both directly and after expansion to

The distribution of YKL-40 in osteoarthritic and normal human articular cartilage

DEFF Research Database (Denmark)

Volck, B; Ostergaard, K; Johansen, J S

1999-01-01

YKL-40, also called human cartilage glycoprotein-39, is a major secretory protein of human chondrocytes in cell culture. YKL-40 mRNA is expressed by cartilage from patients with rheumatoid arthritis, but is not detectable in normal human cartilage. The aim was to investigate the distribution of YKL...... in chondrocytes of osteoarthritic cartilage mainly in the superficial and middle zone of the cartilage rather than the deep zone. There was a tendency for high number of YKL-40 positive chondrocytes in areas of the femoral head with a considerable biomechanical load. The number of chondrocytes with a positive...

Isolation and differentiation of chondrocytic cells derived from human embryonic stem cells using dlk1/FA1 as a novel surface marker

DEFF Research Database (Denmark)

Harkness, Linda; Taipaleenmaki, Hanna; Mahmood, Amer

2009-01-01

of dlk1/FA1 as a novel surface marker for chondroprogenitor cells during hESC differentiation. We found that, Dlk1/FA1 is expressed specifically in cells undergoing transition from proliferating to prehypertrophic chondrocytes during endochondral ossification of the mouse limb. In hESC cells, dlk1/FA1...... was not expressed by undifferentiated hESC, but expressed during in vitro embryoid bodies (hEBs) formation upon down-regulation of undifferentiated markers e.g. Oct 3/4. Similarly, dlk1/FA1 was expressed in chondrocytic cells during in vivo teratoma formation. Interestingly, treatment of hEBs with Activin B......, a member of TGF-ss family, markedly increased Dlk1 expression in association with up-regulation of the mesoderm-specific markers (e.g. FOXF1, KDR and VE-cadherin) and SOX9. dlk1/FA1(+) cells isolated by fluorescence activated cell sorting (FACS) were capable of differentiating into chondrocytic cells when...

Normal proliferation and differentiation of Hoxc-8 transgenic chondrocytes in vitro

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Mello Maria

2003-04-01

Full Text Available Abstract Background Hox genes encode transcription factors that are involved in pattern formation in the skeleton, and recent evidence suggests that they also play a role in the regulation of endochondral ossification. To analyze the role of Hoxc-8 in this process in more detail, we applied in vitro culture systems, using high density cultures of primary chondrocytes from neonatal mouse ribs. Results Cultured cells were characterized on the basis of morphology (light microscopy and production of cartilage-specific extracellular matrix (sulfated proteoglycans and type II Collagen. Hypertrophy was demonstrated by increase in cell size, alkaline phosphatase activity and type X Collagen immunohistochemistry. Proliferation was assessed by BrdU uptake and flow cytometry. Unexpectedly, chondrocytes from Hoxc-8 transgenic mice, which exhibit delayed cartilage maturation in vivo 1, were able to proliferate and differentiate normally in our culture systems. This was the case even though freshly isolated Hoxc-8 transgenic chondrocytes exhibited significant molecular differences as measured by real-time quantitative PCR. Conclusions The results demonstrate that primary rib chondrocytes behave similar to published reports for chondrocytes from other sources, validating in vitro approaches for studies of Hox genes in the regulation of endochondral ossification. Our analysis of cartilage-producing cells from Hoxc-8 transgenic mice provides evidence that the cellular phenotype induced by Hoxc-8 overexpression in vivo is reversible in vitro.

Synergistic chondroprotective effects of curcumin and resveratrol in human articular chondrocytes: inhibition of IL-1beta-induced NF-kappaB-mediated inflammation and apoptosis.

Science.gov (United States)

Csaki, Constanze; Mobasheri, Ali; Shakibaei, Mehdi

2009-01-01

Currently available treatments for osteoarthritis (OA) are restricted to nonsteroidal anti-inflammatory drugs, which exhibit numerous side effects and are only temporarily effective. Thus novel, safe and more efficacious anti-inflammatory agents are needed for OA. Naturally occurring polyphenolic compounds, such as curcumin and resveratrol, are potent agents for modulating inflammation. Both compounds mediate their effects by targeting the NF-kappaB signalling pathway. We have recently demonstrated that in chondrocytes resveratrol modulates the NF-kappaB pathway by inhibiting the proteasome, while curcumin modulates the activation of NF-kappaB by inhibiting upstream kinases (Akt). However, the combinational effects of these compounds in chondrocytes has not been studied and/or compared with their individual effects. The aim of this study was to investigate the potential synergistic effects of curcumin and resveratrol on IL-1beta-stimulated human chondrocytes in vitro using immunoblotting and electron microscopy. Treatment with curcumin and resveratrol suppressed NF-kappaB-regulated gene products involved in inflammation (cyclooxygenase-2, matrix metalloproteinase (MMP)-3, MMP-9, vascular endothelial growth factor), inhibited apoptosis (Bcl-2, Bcl-xL, and TNF-alpha receptor-associated factor 1) and prevented activation of caspase-3. IL-1beta-induced NF-kappaB activation was suppressed directly by cocktails of curcumin and resveratrol through inhibition of Ikappakappa and proteasome activation, inhibition of IkappaBalpha phosphorylation and degradation, and inhibition of nuclear translocation of NF-kappaB. The modulatory effects of curcumin and resveratrol on IL-1beta-induced expression of cartilage specific matrix and proinflammatory enzymes were mediated in part by the cartilage-specific transcription factor Sox-9. We propose that combining these natural compounds may be a useful strategy in OA therapy as compared with separate treatment with each individual

RAGE and activation of chondrocytes and fibroblast-like synoviocytes in joint diseases

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Steenvoorden, Marjan Maria Claziena

2007-01-01

This dissertation describes a new model in which cartilage degradation can be studied. New cartilage is formed by bovine chondrocytes obtained from the slaughterhouse and cocultured with synovial cells from rheumatoid arthritis (RA) patients to study the interaction between the chondrocytes and

Autologous chondrocytes as a novel source for neo-chondrogenesis in haemophiliacs.

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Stocco, Elena; Barbon, Silvia; Radossi, Paolo; Rajendran, Senthilkumar; Dalzoppo, Daniele; Bortolami, Marina; Bagno, Andrea; Grandi, Francesca; Gamba, Pier Giorgio; Parnigotto, Pier Paolo; Tagariello, Giuseppe; Grandi, Claudio

2016-10-01

Haemophilic arthropathy is the major cause of disability in patients with haemophilia and, despite prophylaxis with coagulation factor concentrates, some patients still develop articular complications. We evaluate the feasibility of a tissue engineering approach to improve current clinical strategies for cartilage regeneration in haemophiliacs by using autologous chondrocytes (haemophilic chondrocytes; HaeCs). Little is known about articular chondrocytes from haemophilic patients and no characterisation has as yet been performed. An investigation into whether blood exposure alters HaeCs should be interesting from the perspective of autologous implants. The typical morphology and expression of specific target genes and surface markers were therefore assessed by optical microscopy, reverse transcription plus the polymerase chain reaction (PCR), real-time PCR and flow-cytometry. We then considered chondrocyte behaviour on a bio-hybrid scaffold (based on polyvinyl alcohol/Wharton's jelly) as an in vitro model of articular cartilage prosthesis. Articular chondrocytes from non-haemophilic donors were used as controls. HaeC morphology and the resulting immunophenotype CD44(+)/CD49c(+)/CD49e(+)/CD151(+)/CD73(+)/CD49f(-)/CD26(-) resembled those of healthy donors. Moreover, HaeCs were active in the transcription of genes involved in the synthesis of the extracellular matrix proteins of the articular cartilage (ACAN, COL1A, COL2A, COL10A, COL9A, COMP, HAS1, SOX9), although the over-expression of COL1A1, COL10A1, COMP and HAS was observed. In parallel, the composite scaffold showed adequate mechanical and biological properties for cartilage tissue engineering, promoting chondrocyte proliferation. Our preliminary evidence contributes to the characterisation of HaeCs, highlighting the opportunity of using them for autologous cartilage implants in patients with haemophilia.

Hydrostatic Pressure Regulates MicroRNA Expression Levels in Osteoarthritic Chondrocyte Cultures via the Wnt/β-Catenin Pathway

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Sara Cheleschi

2017-01-01

Full Text Available Mechanical loading and hydrostatic pressure (HP regulate chondrocytes’ metabolism; however, how mechanical stimulation acts remain unclear. MicroRNAs (miRNAs play an important role in cartilage homeostasis, mechanotransduction, and in the pathogenesis of osteoarthritis (OA. This study investigated the effects of a cyclic HP (1–5 MPa, in both normal and OA human chondrocytes, on the expression of miR-27a/b, miR-140, miR-146a/b, and miR-365, and of their target genes (MMP-13, ADAMTS-5, IGFBP-5, and HDAC-4. Furthermore, we assessed the possible involvement of Wnt/β-catenin pathway in response to HP. Chondrocytes were exposed to HP for 3h and the evaluations were performed immediately after pressurization, and following 12, 24, and 48 h. Total RNA was extracted and used for real-time PCR. β-catenin was detected by Western blotting analysis and immunofluorescence. In OA chondrocytes, HP induced a significant increase (p < 0.01 of the expression levels of miR-27a/b, miR-140, and miR-146a, and a significant reduction (p < 0.01 of miR-365 at all analyzed time points. MMP-13, ADAMTS-5, and HDAC-4 were significantly downregulated following HP, while no significant modification was found for IGFBP-5. β-catenin levels were significantly increased (p < 0.001 in OA chondrocytes at basal conditions and significantly reduced (p < 0.01 by HP. Pressurization did not cause any significant modification in normal cells. In conclusion, in OA chondrocytes, HP restores the expression levels of some miRNAs, downregulates MMP-13, ADAMTS-5, and HDAC-4, and modulates the Wnt/β-catenin pathway activation.

Latexin is involved in bone morphogenetic protein-2-induced chondrocyte differentiation

International Nuclear Information System (INIS)

Kadouchi, Ichiro; Sakamoto, Kei; Tangjiao, Liu; Murakami, Takashi; Kobayashi, Eiji; Hoshino, Yuichi; Yamaguchi, Akira

2009-01-01

Latexin is the only known carboxypeptidase A inhibitor in mammals. We previously demonstrated that BMP-2 significantly induced latexin expression in Runx2-deficient mesenchymal cells (RD-C6 cells), during chondrocyte and osteoblast differentiation. In this study, we investigated latexin expression in the skeleton and its role in chondrocyte differentiation. Immunohistochemical studies revealed that proliferating and prehypertrophic chondrocytes expressed latexin during skeletogenesis and bone fracture repair. In the early phase of bone fracture, latexin mRNA expression was dramatically upregulated. BMP-2 upregulated the expression of the mRNAs of latexin, Col2a1, and the gene encoding aggrecan (Agc1) in a micromass culture of C3H10T1/2 cells. Overexpression of latexin additively stimulated the BMP-2-induced expression of the mRNAs of Col2a, Agc1, and Col10a1. BMP-2 treatment upregulated Sox9 expression, and Sox9 stimulated the promoter activity of latexin. These results indicate that latexin is involved in BMP-2-induced chondrocyte differentiation and plays an important role in skeletogenesis and skeletal regeneration.

CCAAT/Enhancer Binding Protein β Regulates Expression of Indian Hedgehog during Chondrocytes Differentiation

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Ushijima, Takahiro; Okazaki, Ken; Tsushima, Hidetoshi; Ishihara, Kohei; Doi, Toshio; Iwamoto, Yukihide

2014-01-01

Background CCAAT/enhancer binding protein β (C/EBPβ) is a transcription factor that promotes hypertrophic differentiation of chondrocytes. Indian hedgehog (Ihh) also stimulates the hypertrophic transition of chondrocytes. Furthermore, runt-related transcription factor-2 (RUNX2) was reported to regulate chondrocyte maturation during skeletal development and to directly regulate transcriptional activity of Ihh. In this study, we investigated whether the interaction of C/EBPβ and RUNX2 regulates the expression of Ihh during chondrocyte differentiation. Methodology/Results Immunohistochemistry of embryonic growth plate revealed that both C/EBPβ and Ihh were strongly expressed in pre-hypertrophic and hypertrophic chondrocytes. Overexpression of C/EBPβ by adenovirus vector in ATDC5 cells caused marked stimulation of Ihh and Runx2. Conversely, knockdown of C/EBPβ by lentivirus expressing shRNA significantly repressed Ihh and Runx2 in ATDC5 cells. A reporter assay revealed that C/EBPβ stimulated transcriptional activity of Ihh. Deletion and mutation analysis showed that the C/EBPβ responsive element was located between −214 and −210 bp in the Ihh promoter. An electrophoretic mobility shift assay (EMSA) and a chromatin immunoprecipitation (ChIP) assay also revealed the direct binding of C/EBPβ to this region. Moreover, reporter assays demonstrated that RUNX2 failed to stimulate the transcriptional activity of the Ihh promoter harboring a mutation at the C/EBPβ binding site. EMSA and ChIP assays showed that RUNX2 interacted to this element with C/EBPβ. Immunoprecipitation revealed that RUNX2 and C/EBPβ formed heterodimer complex with each other in the nuclei of chondrocytes. These data suggested that the C/EBPβ binding element is also important for RUNX2 to regulate the expression of Ihh. Ex vivo organ culture of mouse limbs transfected with C/EBPβ showed that the expression of Ihh and RUNX2 was increased upon ectopic C/EBPβ expression. Conclusions C

CCAAT/enhancer binding protein β regulates expression of Indian hedgehog during chondrocytes differentiation.

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Takahiro Ushijima

Full Text Available CCAAT/enhancer binding protein β (C/EBPβ is a transcription factor that promotes hypertrophic differentiation of chondrocytes. Indian hedgehog (Ihh also stimulates the hypertrophic transition of chondrocytes. Furthermore, runt-related transcription factor-2 (RUNX2 was reported to regulate chondrocyte maturation during skeletal development and to directly regulate transcriptional activity of Ihh. In this study, we investigated whether the interaction of C/EBPβ and RUNX2 regulates the expression of Ihh during chondrocyte differentiation.Immunohistochemistry of embryonic growth plate revealed that both C/EBPβ and Ihh were strongly expressed in pre-hypertrophic and hypertrophic chondrocytes. Overexpression of C/EBPβ by adenovirus vector in ATDC5 cells caused marked stimulation of Ihh and Runx2. Conversely, knockdown of C/EBPβ by lentivirus expressing shRNA significantly repressed Ihh and Runx2 in ATDC5 cells. A reporter assay revealed that C/EBPβ stimulated transcriptional activity of Ihh. Deletion and mutation analysis showed that the C/EBPβ responsive element was located between -214 and -210 bp in the Ihh promoter. An electrophoretic mobility shift assay (EMSA and a chromatin immunoprecipitation (ChIP assay also revealed the direct binding of C/EBPβ to this region. Moreover, reporter assays demonstrated that RUNX2 failed to stimulate the transcriptional activity of the Ihh promoter harboring a mutation at the C/EBPβ binding site. EMSA and ChIP assays showed that RUNX2 interacted to this element with C/EBPβ. Immunoprecipitation revealed that RUNX2 and C/EBPβ formed heterodimer complex with each other in the nuclei of chondrocytes. These data suggested that the C/EBPβ binding element is also important for RUNX2 to regulate the expression of Ihh. Ex vivo organ culture of mouse limbs transfected with C/EBPβ showed that the expression of Ihh and RUNX2 was increased upon ectopic C/EBPβ expression.C/EBPβ and RUNX2 cooperatively stimulate

Engineering Cartilage Tissue by Pellet Coculture of Chondrocytes and Mesenchymal Stromal Cells

NARCIS (Netherlands)

Wu, Ling; Post, Janine Nicole; Karperien, Hermanus Bernardus Johannes; Westendorf, Jennifer J.; van Wijnen, Andre J.

2015-01-01

Coculture of chondrocytes and mesenchymal stromal cells (MSCs) in pellets has been shown to be beneficial in engineering cartilage tissue in vitro. In these cultures trophic effects of MSCs increase the proliferation and matrix deposition of chondrocytes. Thus, large cartilage constructs can be made

Chondroprotective Effects of Ginsenoside Rg1 in  Human Osteoarthritis Chondrocytes and a Rat Model  of Anterior Cruciate Ligament Transection

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Wendan Cheng

2017-03-01

Full Text Available This study aimed to assess whether Ginsenoside Rg1 (Rg1 inhibits inflammatory responses in human chondrocytes and reduces articular cartilage damage in a rat model of osteoarthritis (OA. Gene expression and protein levels of type II collagen, aggrecan, matrix metalloproteinase (MMP‐13 and cyclooxygenase‐2 (COX‐2 were determined in vitro by quantitative real‐time‐polymerase chain reaction and Western blotting. Prostaglandin E2 (PGE2 amounts in the culture medium were determined by enzyme‐linked immunosorbent assay (ELISA. For in vivo assessment, a rat model of OA was generated by anterior cruciate ligament transection (ACLT. Four weeks after ACLT, Rg1 (30 or 60 mg/kg or saline was administered by gavage once a day for eight consecutive weeks. Joint damage was analyzed by histology and immunohistochemistry. Ginsenoside Rg1 inhibited Interleukin (IL‐1β‐induced chondrocyte gene and protein expressions of MMP‐13, COX‐2 and PGE2, and prevented type II collagen and aggrecan degradation, in a dose‐dependent manner. Administration of Ginsenoside Rg1 to OA rats attenuated cartilage degeneration, and reduced type II collagen loss and MMP‐13 levels. These findings demonstrated that Ginsenoside Rg1 can inhibit inflammatory responses in human chondrocytes in vitro and reduce articular cartilage damage in vivo, confirming the potential therapeutic value of Ginsenoside Rg1 in OA.

Treatment of osteoarthritis using a helper-dependent adenoviral vector retargeted to chondrocytes

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Merry ZC Ruan

2016-01-01

Full Text Available Osteoarthritis (OA is a joint disease characterized by degeneration of the articular cartilage, subchondral bone remodeling, and secondary inflammation. It is among the top three causes of chronic disability, and currently there are no treatment options to prevent disease progression. The localized nature of OA makes it an ideal candidate for gene and cell therapy. However, gene and cell therapy of OA is impeded by inefficient gene transduction of chondrocytes. In this study, we developed a broadly applicable system that retargets cell surface receptors by conjugating antibodies to the capsid of helper-dependent adenoviral vectors (HDVs. Specifically, we applied this system to retarget chondrocytes by conjugating an HDV to an α-10 integrin monoclonal antibody (a10mab. We show that a10mab-conjugated HDV (a10mabHDV-infected chondrocytes efficiently in vitro and in vivo while detargeting other cell types. The therapeutic index of an intra-articular injection of 10mabHDV-expressing proteoglycan 4 (PRG4 into a murine model of post-traumatic OA was 10-fold higher than with standard HDV. Moreover, we show that PRG4 overexpression from articular, superficial zone chondrocytes is effective for chondroprotection in postinjury OA and that α-10 integrin is an effective protein for chondrocyte targeting.

Exploration of mechanisms underlying the strain-rate-dependent mechanical property of single chondrocytes

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Nguyen, Trung Dung; Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland (Australia)

2014-05-05

Based on the characterization by Atomic Force Microscopy, we report that the mechanical property of single chondrocytes has dependency on the strain-rates. By comparing the mechanical deformation responses and the Young's moduli of living and fixed chondrocytes at four different strain-rates, we explore the deformation mechanisms underlying this dependency property. We found that the strain-rate-dependent mechanical property of living cells is governed by both of the cellular cytoskeleton and the intracellular fluid when the fixed chondrocytes are mainly governed by their intracellular fluid, which is called the consolidation-dependent deformation behavior. Finally, we report that the porohyperelastic constitutive material model which can capture the consolidation-dependent behavior of both living and fixed chondrocytes is a potential candidature to study living cell biomechanics.

Regulation of hypoxia-inducible factor-1α (HIF-1α expression by interleukin-1β (IL-1 β, insulin-like growth factors I (IGF-I and II (IGF-II in human osteoarthritic chondrocytes

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Angelica Rossi Sartori-Cintra

2012-01-01

Full Text Available OBJECTIVE: Hypoxia-inducible factor 1 alpha regulates genes related to cellular survival under hypoxia. This factor is present in osteroarthritic chondrocytes, and cytokines, such as interleukin-1 beta, participate in the pathogenesis of osteoarthritis, thereby increasing the activities of proteolytic enzymes, such as matrix metalloproteinases, and accelerating cartilage destruction. We hypothesize that Hypoxia Inducible Factor-1 alpha (HIF-1α can regulate cytokines (catabolic action and/or growth factors (anabolic action in osteoarthritis. The purpose of this study was to investigate the modulation of HIF-1α in human osteoarthritic chondrocytes by interleukin-1 beta (IL-1β and insulin-like growth factors I (IGF-I and II (IGF-II and to determine the involvement of the phosphatidylinositol-3kinase (PI-3K pathway in this process. METHODS: Human osteroarthritic chondrocytes were stimulated with IL-1β, IGF-I and IGF-II and LY294002, a specific inhibitor of PI-3K. Nuclear protein levels and gene expression were analyzed by western blot and quantitative reverse transcription-polymerase chain reaction analyses, respectively. RESULTS: HIF-1α expression was upregulated by IL-1β at the protein level but not at the gene level. IGF-I treatment resulted in increases in both the protein and mRNA levels of HIF-1α , whereas IGF-II had no effect on its expression. However, all of these stimuli exploited the PI-3K pathway. CONCLUSION: IL-1β upregulated the levels of HIF-1α protein post-transcriptionally, whereas IGF-I increased HIF-1α at the transcript level. In contrast, IGF-II did not affect the protein or gene expression levels of HIF-1α . Furthermore, all of the tested stimuli exploited the PI-3K pathway to some degree. Based on these findings, we are able to suggest that Hypoxia inducible Factor-1 exhibits protective activity in chondrocytes during osteoarthritis.

Streamlined bioreactor-based production of human cartilage tissues.

Science.gov (United States)

Tonnarelli, B; Santoro, R; Adelaide Asnaghi, M; Wendt, D

2016-05-27

Engineered tissue grafts have been manufactured using methods based predominantly on traditional labour-intensive manual benchtop techniques. These methods impart significant regulatory and economic challenges, hindering the successful translation of engineered tissue products to the clinic. Alternatively, bioreactor-based production systems have the potential to overcome such limitations. In this work, we present an innovative manufacturing approach to engineer cartilage tissue within a single bioreactor system, starting from freshly isolated human primary chondrocytes, through the generation of cartilaginous tissue grafts. The limited number of primary chondrocytes that can be isolated from a small clinically-sized cartilage biopsy could be seeded and extensively expanded directly within a 3D scaffold in our perfusion bioreactor (5.4 ± 0.9 doublings in 2 weeks), bypassing conventional 2D expansion in flasks. Chondrocytes expanded in 3D scaffolds better maintained a chondrogenic phenotype than chondrocytes expanded on plastic flasks (collagen type II mRNA, 18-fold; Sox-9, 11-fold). After this "3D expansion" phase, bioreactor culture conditions were changed to subsequently support chondrogenic differentiation for two weeks. Engineered tissues based on 3D-expanded chondrocytes were more cartilaginous than tissues generated from chondrocytes previously expanded in flasks. We then demonstrated that this streamlined bioreactor-based process could be adapted to effectively generate up-scaled cartilage grafts in a size with clinical relevance (50 mm diameter). Streamlined and robust tissue engineering processes, as the one described here, may be key for the future manufacturing of grafts for clinical applications, as they facilitate the establishment of compact and closed bioreactor-based production systems, with minimal automation requirements, lower operating costs, and increased compliance to regulatory guidelines.

Role of Insulin-Transferrin-Selenium in Auricular Chondrocyte Proliferation and Engineered Cartilage Formation in Vitro

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Xia Liu

2014-01-01

Full Text Available The goal of this study is to determine the effects of Insulin-Transferrin-Selenium (ITS on proliferation of auricular chondrocytes and formation of engineered cartilage in vitro. Pig auricular monolayer chondrocytes and chondrocyte pellets were cultured in media containing 1% ITS at different concentrations of fetal bovine serum (FBS, 10%, 6%, 2%, 0%, or 10% FBS alone as a control for four weeks. Parameters including cell proliferation in monolayer, wet weight, collagen type I/II/X (Col I, II, X and glycosaminoglycan (GAG expression, GAG content of pellets and gene expression associated with cartilage formation/dedifferentiation (lost cartilage phenotype/hypertrophy within the chondrocyte pellets were assessed. The results showed that chondrocytes proliferation rates increased when FBS concentrations increased (2%, 6%, 10% FBS in ITS supplemented groups. In addition, 1% ITS plus 10% FBS significantly promoted cell proliferation than 10% FBS alone. No chondrocytes grew in ITS alone medium. 1% ITS plus 10% FBS enhanced cartilage formation in terms of size, wet weight, cartilage specific matrices, and homogeneity, compared to 10% FBS alone group. Furthermore, ITS prevented engineered cartilage from dedifferentiation (i.e., higher index of Col II/Col I mRNA expression and expression of aggrecan and hypertrophy (i.e., lower mRNA expression of Col X and MMP13. In conclusion, our results indicated that ITS efficiently enhanced auricular chondrocytes proliferation, retained chondrogenic phenotypes, and promoted engineered cartilage formation when combined with FBS, which is potentially used as key supplementation in auricular chondrocytes and engineered cartilage culture.

Articular chondrocyte metabolism and osteoarthritis

Energy Technology Data Exchange (ETDEWEB)

Leipold, H.R.

1989-01-01

The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in synovial fluids correlated with higher keratan sulfate in serum. The mean keratan sulfate concentration in sera of older dogs with osteoarthritis was 37% higher than disease-free controls, but the difference between the groups was not statistically significant. Treatment of chondrocytes with 0.5 millimolar (mM) dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. There was no difference between the amount of proteins synthesized by cultures treated with DBcAMP and controls. The amount of fibronectin (FN) in the media of DBcAMP treated cultures detected by an ELISA was specifically reduced, and the amount of {sup 35}S-FN purified by gelatin affinity chromatography decreased. Moreover, the percentage of FN containing the extra domain. A sequence was reduced. Concomitant with the decrease in FN there was an increase in the concentration of keratan sulfate.

Bauhinia championi (Benth.) Benth. polysaccharides upregulate Wnt/β-catenin signaling in chondrocytes.

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Li, Huiting; Li, Xihai; Liu, Guozhong; Chen, Jiashou; Weng, Xiaping; Liu, Fayuan; Xu, Huifeng; Liu, Xianxiang; Ye, Hongzhi

2013-12-01

Bauhinia championi (Benth.) Benth. polysaccharides (BCBPs), extracted from Bauhinia championi (Benth.) Benth., which has been used in traditional Chinese medicine (TCM) for the treatment of osteoarthritis (OA), are the bioactive constituents of Bauhinia championi (Benth.) rattan. However, the molecular mechanisms responsible for their effects on OA are poorly understood. The Wnt/β-catenin signaling pathway plays an important role in the proliferation of chondrocytes. In the present study, the effects of BCBPs on Wnt/β-catenin signaling in chondrocytes were investigated. BCBPs were obtained by hot-water extraction and identified by the modified high performance liquid chromatography (HPLC) method. Chondrocytes were isolated from the knees of Sprague‑Dawley rats and identified by type II collagen immunohistochemistry. The chondrocytes were treated with or without BCBPs for 48 h. Cell viability was evaluated by MTT assay. The mRNA and protein levels of Wnt-4, β-catenin, Frizzled-2, glycogen synthase kinase (GSK)-3β, cyclin D1 and collagen II were detected by western blot analysis and reverse transcription PCR (RT-PCR), respectively. We found that the BCBPs contained at least seven monosaccharides, including D-mannose, rhamnose, D-(+) glucuronic acid, D-(+) galacturonic acid, D-glucose, galactose and arabinose. The cell viability of the chondrocytes treated with 50, 100 and 200 µg/ml BCBPs was significantly higher than that of the chondroctyes in the control group (treated with 0 µg/ml BCBPs). Furthermore, compared with the control group, the mRNA and protein expression of Wnt-4, β-catenin, Frizzled-2 and cyclin D1 in the BCBP-treated groups markedly increased, whereas the mRNA and protein expression of GSK-3β significantly decreased. Of note, the dose of 100 µg/ml BCBPs was more effective than the dose of 50 µg/ml BCBPs and 200 µg/ml BCBPs. In addition, we found that treatment with BCBPs upregulated the protein levels of collagen II in the

Fate of Meckel's cartilage chondrocytes in ocular culture

International Nuclear Information System (INIS)

Richman, J.M.; Diewert, V.M.

1988-01-01

Modulation of the chondrocyte phenotype was observed in an organ culture system using Meckel's cartilage. First branchial arch cartilage was dissected from fetal rats of 16- and 17-day gestation. Perichondrium was mechanically removed, cartilage was split at the rostral process, and each half was grafted into the anterior chamber of an adult rat eye. The observed pattern of development in nonirradiated specimens was the following: hypertrophy of the rostral process and endochondral-type ossification, fibrous atrophy in the midsection, and mineralization of the malleus and incus. A change in matrix composition of the implanted cartilage was demonstrated with immunofluorescence staining for cartilage-specific proteoglycan (CSPG). After 15 days of culture, CSPG was found in the auricular process but not in the midsection or rostral process. In order to mark the implanted cells and follow their fate, cartilage was labeled in vitro with [3H]thymidine [3H]TdR). Immediately after labeling 20% of the chondrocytes contained [3H]TdR. After culturing for 5 days, 20% of the chondrocytes were still labeled and 10% of the osteogenic cells also contained radioactive label. The labeling index decreased in both cell types with increased duration of culture. Multinucleated clast-type cells did not contain label. Additional cartilages not labeled with [3H]TdR were exposed to between 20000 and 6000 rad of gamma irradiation before ocular implantation. Irradiated cartilage did not hypertrophy or form bone but a fibrous region developed in the midsection. Cells of the host animal were not induced to form bone around the irradiated cartilage. Our studies suggest that fully differentiated chondrocytes of Meckel's cartilage have the capacity to become osteocytes, osteoblasts, and fibroblasts

The Ihh signal is essential for regulating proliferation and hypertrophy of cultured chicken chondrocytes.

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Ma, R S; Zhou, Z L; Luo, J W; Zhang, H; Hou, J F

2013-10-01

The Indian hedgehog (Ihh) signal plays a vital role in regulating proliferation and hypertrophy of chondrocytes. To investigate its function in postnatal chicken (Gallus gallus) chondrocytes, cyclopamine was used to inhibit Ihh signaling. The MTT and ALP assays revealed the downgrade-proliferation and upgrade-differentiation of chondrocytes. To further elucidate the mechanism, the mRNA expression levels of Ihh, parathyroid hormone related protein (PTHrP), Gli-2, Bcl-2, Bone Morphogenetic Protein 6 (BMP-6), type X collagen (Col X) and type II collagen (Col II) were detected by quantitative real-time RT-PCR analysis, and the protein expressions of Ihh, Col X, and Col II were determined using Western blot analysis. After the Ihh signal was blocked, chondrocytes demonstrated high expression levels of PTHrP and Col X and low levels of Gli-2, BMP-6, Bcl-2 and Col II although Ihh expression was increased. Based on these results, the Ihh signal is essential for balancing chicken chondrocyte proliferation and hypertrophy, and the regulatory function of PTHrP acts in an Ihh-dependent manner. Furthermore, BMP-6 and Bcl-2 played roles in maintaining the development of chondrocytes and may be downstream regulatory factors of Ihh signaling. © 2013.

TNF/TNFR1 pathway and endoplasmic reticulum stress are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes

International Nuclear Information System (INIS)

Zhang, Fu-Tao; Ding, Yi; Shah, Zahir; Xing, Dan; Gao, Yuan; Liu, Dong Ming; Ding, Ming-Xing

2014-01-01

Background and purpose: Quinolones cause obvious cartilaginous lesions in juvenile animals by chondrocyte apoptosis, which results in the restriction of their use in pediatric and adolescent patients. Studies showed that chondrocytes can be induced to produce TNFα, and the cisternae of the endoplasmic reticulum in quinolone-treated chondrocytes become dilated. We investigated whether TNF/TNFR 1 pathway and endoplasmic reticulum stress (ERs) are involved in ofloxacin (a typical quinolone)-induced apoptosis of juvenile canine chondrocytes. Experimental approach: Canine juvenile chondrocytes were treated with ofloxacin. Cell survival and apoptosis rates were determined with MTT method and flow cytometry, respectively. The gene expression levels of the related signaling molecules (TNFα, TNFR 1 , TRADD, FADD and caspase-8) in death receptor pathways and main apoptosis-related molecules (calpain, caspase-12, GADD153 and GRP78) in ERs were measured by qRT-PCR. The gene expression of TNFR 1 was suppressed with its siRNA. The protein levels of TNFα, TNFR 1 and caspase-12 were assayed using Western blotting. Key results: The survival rates decreased while apoptosis rates increased after the chondrocytes were treated with ofloxacin. The mRNA levels of the measured apoptosis-related molecules in death receptor pathways and ERs, and the protein levels of TNFα, TNFR 1 and caspase-12 increased after the chondrocytes were exposed to ofloxacin. The downregulated mRNA expressions of TNFR 1 , Caspase-8 and TRADD, and the decreased apoptosis rates of the ofloxacin-treated chondrocytes occurred after TNFR 1 –siRNA interference. Conclusions and implications: Ofloxacin-induced chondrocyte apoptosis in a time- and concentration-dependent fashion. TNF/TNFR 1 pathway and ERs are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes in the early stage. - Highlights: • Chondrocyte apoptosis is induced by ofloxacin in a time- and concentration-dependent manners. �

IL-1β Suppresses the Formation of Osteoclasts by Increasing OPG Production via an Autocrine Mechanism Involving Celecoxib-Related Prostaglandins in Chondrocytes

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Yusuke Watanabe

2009-01-01

Full Text Available Elevated interleukin (IL-1 concentrations in synovial fluid have been implicated in joint bone and cartilage destruction. Previously, we showed that IL-1β stimulated the expression of prostaglandin (PG receptor EP4 via increased PGE2 production. However, the effect of IL-1β on osteoclast formation via chondrocytes is unclear. Therefore, we examined the effect of IL-1β and/or celecoxib on the expression of macrophage colony-stimulating factor (M-CSF, receptor activator of NF-κB ligand (RANKL, and osteoprotegerin (OPG in human chondrocytes, and the indirect effect of IL-1β on osteoclast-like cell formation using RAW264.7 cells. OPG and RANKL expression increased with IL-1β; whereas M-CSF expression decreased. Celecoxib blocked the stimulatory effect of IL-1β. Conditioned medium from IL-1β-treated chondrocytes decreased TRAP staining in RAW264.7 cells. These results suggest that IL-1β suppresses the formation of osteoclast-like cells via increased OPG production and decreased M-CSF production in chondrocytes, and OPG production may increase through an autocrine mechanism involving celecoxib-related PGs.

Gli3 acts as a repressor downstream of Ihh in regulating two distinct steps of chondrocyte differentiation.

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Koziel, Lydia; Wuelling, Manuela; Schneider, Sabine; Vortkamp, Andrea

2005-12-01

During endochondral ossification, the secreted growth factor Indian hedgehog (Ihh) regulates several differentiation steps. It interacts with a second secreted factor, parathyroid hormone-related protein (PTHrP), to regulate the onset of hypertrophic differentiation, and it regulates chondrocyte proliferation and ossification of the perichondrium independently of PTHrP. To investigate how the Ihh signal is translated in the different target tissues, we analyzed the role of the zinc-finger transcription factor Gli3, which acts downstream of hedgehog signals in other organs. Loss of Gli3 in Ihh mutants restores chondrocyte proliferation and delays the accelerated onset of hypertrophic differentiation observed in Ihh-/- mutants. Furthermore the expression of the Ihh target genes patched (Ptch) and PTHrP is reactivated in Ihh-/-;Gli3-/- mutants. Gli3 seems thus to act as a strong repressor of Ihh signals in regulating chondrocyte differentiation. In addition, loss of Gli3 in mice that overexpress Ihh in chondrocytes accelerates the onset of hypertrophic differentiation by reducing the domain and possibly the level of PTHrP expression. Careful analysis of chondrocyte differentiation in Gli3-/- mutants revealed that Gli3 negatively regulates the differentiation of distal, low proliferating chondrocytes into columnar, high proliferating cells. Our results suggest a model in which the Ihh/Gli3 system regulates two distinct steps of chondrocyte differentiation: (1) the switch from distal into columnar chondrocytes is repressed by Gli3 in a PTHrP-independent mechanism; (2) the transition from proliferating into hypertrophic chondrocytes is regulated by Gli3-dependent expression of PTHrP. Furthermore, by regulating distal chondrocyte differentiation, Gli3 seems to position the domain of PTHrP expression.

Redifferentiation of in vitro expanded adult articular chondrocytes by combining the hanging-drop cultivation method with hypoxic environment.

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Martinez, Inigo; Elvenes, Jan; Olsen, Randi; Bertheussen, Kjell; Johansen, Oddmund

2008-01-01

The main purpose of this work has been to establish a new culturing technique to improve the chondrogenic commitment of isolated adult human chondrocytes, with the aim of being used during cell-based therapies or tissue engineering strategies. By using a rather novel technique to generate scaffold-free three-dimensional (3D) structures from in vitro expanded chondrocytes, we have explored the effects of different culture environments on cartilage formation. Three-dimensional chondrospheroids were developed by applying the hanging-drop technique. Cartilage tissue formation was attempted after combining critical factors such as serum-containing or serum-free media and atmospheric (20%) or low (2.5%) oxygen tensions. The quality of the formed microtissues was analyzed by histology, immunohistochemistry, electron microscopy, and real-time PCR, and directly compared with native adult cartilage. Our results revealed highly organized, 3D tissue-like structures developed by the hanging-drop method. All culture conditions allowed formation of 3D spheroids; however, cartilage generated under low oxygen tension had a bigger size, enhanced matrix deposition, and higher quality of cartilage formation. Real-time PCR demonstrated enhanced expression of cartilage-specific genes such us collagen type II and aggrecan in 3D cultures when compared to monolayers. Cartilage-specific matrix proteins and genes expressed in hanging-drop-developed spheroids were comparable to the expression obtained by applying the pellet culture system. In summary, our results indicate that a combination of 3D cultures of chondrocytes in hanging drops and a low oxygen environment represent an easy and convenient way to generate cartilage-like microstructures. We also show that a new specially tailored serum-free medium is suitable for in vitro cartilage tissue formation. This new methodology opens up the possibility of using autogenously produced solid 3D structures with redifferentiated chondrocytes as an

Increased adipogenesis in cultured embryonic chondrocytes and in adult bone marrow of dominant negative Erg transgenic mice.

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Sébastien Flajollet

Full Text Available In monolayer culture, primary articular chondrocytes have an intrinsic tendency to lose their phenotype during expansion. The molecular events underlying this chondrocyte dedifferentiation are still largely unknown. Several transcription factors are important for chondrocyte differentiation. The Ets transcription factor family may be involved in skeletal development. One family member, the Erg gene, is mainly expressed during cartilage formation. To further investigate the potential role of Erg in the maintenance of the chondrocyte phenotype, we isolated and cultured chondrocytes from the rib cartilage of embryos of transgenic mice that express a dominant negative form of Erg (DN-Erg during cartilage formation. DN-Erg expression in chondrocytes cultured for up to 20 days did not affect the early dedifferentiation usually observed in cultured chondrocytes. However, lipid droplets accumulated in DN-Erg chondrocytes, suggesting adipocyte emergence. Transcriptomic analysis using a DNA microarray, validated by quantitative RT-PCR, revealed strong differential gene expression, with a decrease in chondrogenesis-related markers and an increase in adipogenesis-related gene expression in cultured DN-Erg chondrocytes. These results indicate that Erg is involved in either maintaining the chondrogenic phenotype in vitro or in cell fate orientation. Along with the in vitro studies, we compared adipocyte presence in wild-type and transgenic mice skeletons. Histological investigations revealed an increase in the number of adipocytes in the bone marrow of adult DN-Erg mice even though no adipocytes were detected in embryonic cartilage or bone. These findings suggest that the Ets transcription factor family may contribute to the homeostatic balance in skeleton cell plasticity.

Assay for plasma somatomedin: (/sup 3/H)thymidine incorporation by isolated rabbit chondrocytes

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Ashton, I K; Francis, M J.O. [Nuffield Orthopaedic Centre, Oxford (UK)

1977-01-01

The incorporation of (/sup 3/H)thymidine by rabbit chondrocytes in vitro has been developed as a sensitive assay for plasma somatomedin. A concentration of normal plasma of 2.5% enhanced (/sup 3/H)thymidine incorporation by 5- to 20-fold compared with basal levels in the absence of plasma. The mean potency of plasma from normal adult men was 0.96 +-0.1 u./ml (mean +- S.D.) and from acromegalic patients 1.9 +- 0.4 u./ml. The apparent potency of hypopituitary plasma alone increased on heating which suggested the presence of heat-labile inhibitors of somatomedin activity. The potency of heated hypopituitary plasma (0.6 +- 0.09 u./ml) remained significantly lower (P < 0.01) than normal plasma. Human growth hormone (0.1 to 20 ..mu..u/ml), bovine growth hormone (0.5 to 20 ..mu..u/ml), insulin (0.5 to 5 ..mu..u/ml) and glucose (0.3 to 2 mmol/l) had no direct effect on the incorporation of (/sup 3/H)thymidine. Chondrocytes which had been previously stored frozen also showed a response to plasma somatomedin.

Do chondroitin sulfates with different structures have different activities on chondrocytes and macrophages?

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da Cunha, André L; Aguiar, Jair A K; Correa da Silva, Flavio S; Michelacci, Yara M

2017-10-01

The aim of the present study was to investigate the activities of natural chondroitin sulfates (CS) with different structures on cultured chondrocytes and macrophages. CS were isolated from cartilages of bovine trachea (BT), porcine trachea (PT), chicken sternum (Ch) and skate (Sk). The preparations were 90-98% pure, with ∼1% proteins, nucleic acids and keratan sulfate contaminants. Structural analysis of these CS and of commercial chondroitin 4- and 6-sulfate (C4S, C6S) have shown that most of their disaccharides are monosulfated, with varying proportions of 4- and 6-sulfation, and 2-7% non-sulfated disaccharides. Sk-CS and C6S contained detectable amounts of disulfated disaccharides. All the CS were polydisperse, with modal molecular weights of 26-135kDa. These CS had anti-inflammatory activities on both chondrocytes and macrophages, but with different efficiencies. On horse and human chondrocytes, they reduced the IL-1β-induced liberation of NO and PGE 2 , and on RAW 264.7 immortalized macrophage-like cell line, C4S, C6S, Ch and Sk-CS decreased the LPS-induced liberation of TNF-α, but did not affect IL-6. In contrast, on bone marrow derived macrophages, C4S, C6S, BT and PT-CS reduced the LPS-induced liberation of TNF-α, IL-6, IL-1β and NO, indicating that the RAW response to CS was different from that of primary macrophages. Copyright © 2017 Elsevier B.V. All rights reserved.

TNF/TNFR{sub 1} pathway and endoplasmic reticulum stress are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes

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Zhang, Fu-Tao; Ding, Yi; Shah, Zahir; Xing, Dan; Gao, Yuan; Liu, Dong Ming; Ding, Ming-Xing, E-mail: dmx@mail.hzau.edu.cn

2014-04-15

Background and purpose: Quinolones cause obvious cartilaginous lesions in juvenile animals by chondrocyte apoptosis, which results in the restriction of their use in pediatric and adolescent patients. Studies showed that chondrocytes can be induced to produce TNFα, and the cisternae of the endoplasmic reticulum in quinolone-treated chondrocytes become dilated. We investigated whether TNF/TNFR{sub 1} pathway and endoplasmic reticulum stress (ERs) are involved in ofloxacin (a typical quinolone)-induced apoptosis of juvenile canine chondrocytes. Experimental approach: Canine juvenile chondrocytes were treated with ofloxacin. Cell survival and apoptosis rates were determined with MTT method and flow cytometry, respectively. The gene expression levels of the related signaling molecules (TNFα, TNFR{sub 1}, TRADD, FADD and caspase-8) in death receptor pathways and main apoptosis-related molecules (calpain, caspase-12, GADD153 and GRP78) in ERs were measured by qRT-PCR. The gene expression of TNFR{sub 1} was suppressed with its siRNA. The protein levels of TNFα, TNFR{sub 1} and caspase-12 were assayed using Western blotting. Key results: The survival rates decreased while apoptosis rates increased after the chondrocytes were treated with ofloxacin. The mRNA levels of the measured apoptosis-related molecules in death receptor pathways and ERs, and the protein levels of TNFα, TNFR{sub 1} and caspase-12 increased after the chondrocytes were exposed to ofloxacin. The downregulated mRNA expressions of TNFR{sub 1}, Caspase-8 and TRADD, and the decreased apoptosis rates of the ofloxacin-treated chondrocytes occurred after TNFR{sub 1}–siRNA interference. Conclusions and implications: Ofloxacin-induced chondrocyte apoptosis in a time- and concentration-dependent fashion. TNF/TNFR{sub 1} pathway and ERs are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes in the early stage. - Highlights: • Chondrocyte apoptosis is induced by ofloxacin in a time- and

ACTIVITY OF CANONICAL WNT SIGNAL SYSTEM IN HYALINE CARTILAGE ARTICULAR CHONDROCYTES IN PROCESS OF SYNOVIAL JOINT DEVELOPMENT

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A.O. Molotkov

2009-03-01

Full Text Available Canonical and non-canonical Wnt systems are essential regulators of chondrogenesis and bone development. However, the roles of these systems in synovial joint development are not well studied. To determine if canonical Wnt system is active in developing articular chondrocytes we used immunohistochemistry for в-galactosidase and doublecortin (cell-type specific marker for articular chondrocytes to double label sections through joint regions of E14.5, E18.5, P10 and adult mice. Here the following results are presented. Canonical Wnt signal system does not work in developing articular chondrocytes at early embryonic stages (E14.5; it is active in the articular chondrocytes at late embryonic stages (E16.5-E18.5 and during postnatal development (P7-P10, but is turned off again in the adult articular chondrocytes. These results suggest that canonical Wnt signaling is being regulated during articular chondrocytes differentiation and joint formation.

MRI evaluation of a new scaffold-based allogenic chondrocyte implantation for cartilage repair

International Nuclear Information System (INIS)

Dhollander, A.A.M.; Huysse, W.C.J.; Verdonk, P.C.M.; Verstraete, K.L.; Verdonk, R.; Verbruggen, G.; Almqvist, K.F.

2010-01-01

Aim: The present study was designed to evaluate the implantation of alginate beads containing human mature allogenic chondrocytes for the treatment of symptomatic cartilage defects of the knee. MRI was used for the morphological analysis of cartilage repair. The correlation between MRI findings and clinical outcome was also studied. Methods: A biodegradable, alginate-based biocompatible scaffold containing human mature allogenic chondrocytes was used for the treatment of symptomatic chondral and osteochondral lesions in the knee. Twenty-one patients were prospectively evaluated with use of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Visual Analogue Scale (VAS) for pain preoperatively and at 3, 6, 9 and 12 months of follow-up. Of the 21 patients, 12 had consented to follow the postoperative MRI evaluation protocol. MRI data were analyzed based on the original MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) and modified MOCART scoring system. The correlation between the clinical outcome and MRI findings was evaluated. Results: A statistically significant clinical improvement became apparent after 6 months and patients continued to improve during the 12 months of follow-up. One of the two MRI scoring systems that were used, showed a statistically significant deterioration of the repair tissue at 1 year of follow-up. Twelve months after the operation complete filling or hypertrophy was found in 41.6%. Bone-marrow edema and effusion were seen in 41.7% and 25% of the study patients, respectively. We did not find a consistent correlation between the MRI criteria and the clinical results. Discussion: The present study confirmed the primary role of MRI in the evaluation of cartilage repair. Two MOCART-based scoring systems were used in a longitudinal fashion and allowed a practical and morphological evaluation of the repair tissue. However, the correlation between clinical outcome and MRI findings was poor. Further

MRI evaluation of a new scaffold-based allogenic chondrocyte implantation for cartilage repair

Energy Technology Data Exchange (ETDEWEB)

Dhollander, A.A.M., E-mail: Aad.Dhollander@Ugent.b [Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, 1P5, B9000 Gent (Belgium); Huysse, W.C.J., E-mail: Wouter.Huysse@Ugent.b [Department of Radiology, Ghent University Hospital, De Pintelaan 185, -1K12 IB, B9000 Gent (Belgium); Verdonk, P.C.M., E-mail: pverdonk@yahoo.co [Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, 1P5, B9000 Gent (Belgium); Verstraete, K.L., E-mail: Koenraad.Verstraete@Ugent.b [Department of Radiology, Ghent University Hospital, De Pintelaan 185, -1K12 IB, B9000 Gent (Belgium); Verdonk, R., E-mail: Rene.Verdonk@Ugent.b [Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, 1P5, B9000 Gent (Belgium); Verbruggen, G., E-mail: Gust.Verbruggen@Ugent.b [Laboratory of Connective Tissue Biology, Department of Rheumatology, Ghent University Hospital, De Pintelaan 185, Ghent (Belgium); Almqvist, K.F., E-mail: Fredrik.Almqvist@Ugent.b [Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, 1P5, B9000 Gent (Belgium)

2010-07-15

Aim: The present study was designed to evaluate the implantation of alginate beads containing human mature allogenic chondrocytes for the treatment of symptomatic cartilage defects of the knee. MRI was used for the morphological analysis of cartilage repair. The correlation between MRI findings and clinical outcome was also studied. Methods: A biodegradable, alginate-based biocompatible scaffold containing human mature allogenic chondrocytes was used for the treatment of symptomatic chondral and osteochondral lesions in the knee. Twenty-one patients were prospectively evaluated with use of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Visual Analogue Scale (VAS) for pain preoperatively and at 3, 6, 9 and 12 months of follow-up. Of the 21 patients, 12 had consented to follow the postoperative MRI evaluation protocol. MRI data were analyzed based on the original MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) and modified MOCART scoring system. The correlation between the clinical outcome and MRI findings was evaluated. Results: A statistically significant clinical improvement became apparent after 6 months and patients continued to improve during the 12 months of follow-up. One of the two MRI scoring systems that were used, showed a statistically significant deterioration of the repair tissue at 1 year of follow-up. Twelve months after the operation complete filling or hypertrophy was found in 41.6%. Bone-marrow edema and effusion were seen in 41.7% and 25% of the study patients, respectively. We did not find a consistent correlation between the MRI criteria and the clinical results. Discussion: The present study confirmed the primary role of MRI in the evaluation of cartilage repair. Two MOCART-based scoring systems were used in a longitudinal fashion and allowed a practical and morphological evaluation of the repair tissue. However, the correlation between clinical outcome and MRI findings was poor. Further

Human and murine very small embryonic-like cells represent multipotent tissue progenitors, in vitro and in vivo.

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Havens, Aaron M; Sun, Hongli; Shiozawa, Yusuke; Jung, Younghun; Wang, Jingcheng; Mishra, Anjali; Jiang, Yajuan; O'Neill, David W; Krebsbach, Paul H; Rodgerson, Denis O; Taichman, Russell S

2014-04-01

The purpose of this study was to determine the lineage progression of human and murine very small embryonic-like (HuVSEL or MuVSEL) cells in vitro and in vivo. In vitro, HuVSEL and MuVSEL cells differentiated into cells of all three embryonic germ layers. HuVSEL cells produced robust mineralized tissue of human origin compared with controls in calvarial defects. Immunohistochemistry demonstrated that the HuVSEL cells gave rise to neurons, adipocytes, chondrocytes, and osteoblasts within the calvarial defects. MuVSEL cells were also able to differentiate into similar lineages. First round serial transplants of MuVSEL cells into irradiated osseous sites demonstrated that ∼60% of the cells maintained their VSEL cell phenotype while other cells differentiated into multiple tissues at 3 months. Secondary transplants did not identify donor VSEL cells, suggesting limited self renewal but did demonstrate VSEL cell derivatives in situ for up to 1 year. At no point were teratomas identified. These studies show that VSEL cells produce multiple cellular structures in vivo and in vitro and lay the foundation for future cell-based regenerative therapies for osseous, neural, and connective tissue disorders.

Biological and Chemical Removal of Primary Cilia Affects Mechanical Activation of Chondrogenesis Markers in Chondroprogenitors and Hypertrophic Chondrocytes.

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Deren, Matthew E; Yang, Xu; Guan, Yingjie; Chen, Qian

2016-02-04

Chondroprogenitors and hypertrophic chondrocytes, which are the first and last stages of the chondrocyte differentiation process, respectively, are sensitive to mechanical signals. We hypothesize that the mechanical sensitivity of these cells depends on the cell surface primary cilia. To test this hypothesis, we removed the primary cilia by biological means with transfection with intraflagellar transport protein 88 (IFT88) siRNA or by chemical means with chloral hydrate treatment. Transfection of IFT88 siRNA significantly reduced the percentage of ciliated cells in both chondroprogenitor ATDC5 cells as well as primary hypertrophic chondrocytes. Cyclic loading (1 Hz, 10% matrix deformation) of ATDC5 cells in three-dimensional (3D) culture stimulates the mRNA levels of chondrogenesis marker Type II collagen (Col II), hypertrophic chondrocyte marker Type X collagen (Col X), and a molecular regulator of chondrogenesis and chondrocyte hypertrophy bone morphogenetic protein 2 (BMP-2). The reduction of ciliated chondroprogenitors abolishes mechanical stimulation of Col II, Col X, and BMP-2. In contrast, cyclic loading stimulates Col X mRNA levels in hypertrophic chondrocytes, but not those of Col II and BMP-2. Both biological and chemical reduction of ciliated hypertrophic chondrocytes reduced but failed to abolish mechanical stimulation of Col X mRNA levels. Thus, primary cilia play a major role in mechanical stimulation of chondrogenesis and chondrocyte hypertrophy in chondroprogenitor cells and at least a partial role in hypertrophic chondrocytes.

Biological and Chemical Removal of Primary Cilia Affects Mechanical Activation of Chondrogenesis Markers in Chondroprogenitors and Hypertrophic Chondrocytes

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Matthew E. Deren

2016-02-01

Full Text Available Chondroprogenitors and hypertrophic chondrocytes, which are the first and last stages of the chondrocyte differentiation process, respectively, are sensitive to mechanical signals. We hypothesize that the mechanical sensitivity of these cells depends on the cell surface primary cilia. To test this hypothesis, we removed the primary cilia by biological means with transfection with intraflagellar transport protein 88 (IFT88 siRNA or by chemical means with chloral hydrate treatment. Transfection of IFT88 siRNA significantly reduced the percentage of ciliated cells in both chondroprogenitor ATDC5 cells as well as primary hypertrophic chondrocytes. Cyclic loading (1 Hz, 10% matrix deformation of ATDC5 cells in three-dimensional (3D culture stimulates the mRNA levels of chondrogenesis marker Type II collagen (Col II, hypertrophic chondrocyte marker Type X collagen (Col X, and a molecular regulator of chondrogenesis and chondrocyte hypertrophy bone morphogenetic protein 2 (BMP-2. The reduction of ciliated chondroprogenitors abolishes mechanical stimulation of Col II, Col X, and BMP-2. In contrast, cyclic loading stimulates Col X mRNA levels in hypertrophic chondrocytes, but not those of Col II and BMP-2. Both biological and chemical reduction of ciliated hypertrophic chondrocytes reduced but failed to abolish mechanical stimulation of Col X mRNA levels. Thus, primary cilia play a major role in mechanical stimulation of chondrogenesis and chondrocyte hypertrophy in chondroprogenitor cells and at least a partial role in hypertrophic chondrocytes.

Comparison of Efficacy of Endogenous and Exogenous IGF-I in Stimulating Matrix Production in Neonatal and Mature Chondrocytes.

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Aguilar, Izath N; Trippel, Stephen B; Shi, Shuiliang; Bonassar, Lawrence J

2015-10-01

The goal of this study was to compare the efficacy of endogenous upregulation of IGF-I by gene therapy and exogenous addition of insulin-like growth factor I (IGF-I) in enhancing proteoglycan synthesis by skeletally mature and neonatal chondrocytes. Chondrocyte transplantation therapy is a common treatment for focal cartilage lesions, with both mature and neonatal chondrocytes used as a cell source. Additionally, gene therapy strategies to upregulate growth factors such as IGF-I have been proposed to augment chondrocyte transplantation therapies. Both skeletally mature and neonatal chondrocytes were exposed to either an adeno-associated virus-based plasmid containing the IGF-I gene or exogenous IGF-I. Analysis of IGF-I and glycosaminoglycan production using a 4-parameter dose-response model established a clear connection between the amount of IGF-I produced by cells and their biosynthetic response. Both neonatal and mature chondrocytes showed this relationship, but the sensitivities were quite different, with EC50 of 0.57 ng/mL for neonatal chondrocytes and EC50 of 8.70 ng/mL IGF-I for skeletally mature chondrocytes. These data suggest that IGF-I gene therapy may be more effective with younger cell sources. Both cell types were less sensitive to exogenous IGF-I than endogenous IGF-I.

Inhibition of cyclooxygenase-2 impacts chondrocyte hypertrophic differentiation during endochondral ossification

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TJM Welting

2011-12-01

Full Text Available Skeletogenesis and bone fracture healing involve endochondral ossification, a process during which cartilaginous primordia are gradually replaced by bone tissue. In line with a role for cyclooxygenase-2 (COX-2 in the endochondral ossification process, non-steroidal anti-inflammatory drugs (NSAIDs were reported to negatively affect bone fracture healing due to impaired osteogenesis. However, a role for COX-2 activity in the chondrogenic phase of endochondral ossification has not been addressed before. We show that COX-2 activity fulfils an important regulatory function in chondrocyte hypertrophic differentiation. Our data reveal essential cross-talk between COX-2 and bone morphogenic protein-2 (BMP-2 during chondrocyte hypertrophic differentiation. BMP-2 mediated chondrocyte hypertrophy is associated with increased COX-2 expression and pharmacological inhibition of COX-2 activity by NSAIDs (e.g., Celecoxib decreases hypertrophic differentiation in various chondrogenic models in vitro and in vivo, while leaving early chondrogenic development unaltered. Our findings demonstrate that COX-2 activity is a novel factor partaking in chondrocyte hypertrophy in the context of endochondral ossification and these observations provide a novel etiological perspective on the adverse effects of NSAIDs on bone fracture healing and have important implications for the use of NSAIDs during endochondral skeletal development.

Chondrocyte activity is increased in psoriatic arthritis and axial spondyloarthritis

DEFF Research Database (Denmark)

Gudmann, Natasja Stæhr; Munk, Heidi Lausten; Christensen, Anne Friesgaard

2016-01-01

. There is a need for biomarkers reflecting core disease pathways for diagnosis and disease mapping. Pro-C2 reflects mature cartilage collagen type IIB formation, while C-Col10 represents turnover of type X collagen, which is exclusively expressed by hypertrophic chondrocytes. The objectives of this study were......SpA undergoing TNFi treatment may reflect that hypertrophic chondrocytes in axSpA are targeted by TNFi. ROC curve analysis showed a diagnostic potential for Pro-C2 in axSpA and PsA....

A Tumor Suppressor Gene Product, Platelet-Derived Growth Factor Receptor-Like Protein Controls Chondrocyte Proliferation and Differentiation.

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Kawata, Kazumi; Kubota, Satoshi; Eguchi, Takanori; Aoyama, Eriko; Moritani, Norifumi H; Oka, Morihiko; Kawaki, Harumi; Takigawa, Masaharu

2017-11-01

The platelet-derived growth factor receptor-like (PDGFRL) gene is regarded as a tumor suppressor gene. However, nothing is known about the molecular function of PDGFRL. In this study, we initially clarified its function in chondrocytes. Among all cell lines examined, the PDGFRL mRNA level was the highest in chondrocytic HCS-2/8 cells. Interestingly, the proliferation of chondrocytic HCS-2/8 cells was promoted by PDGFRL overexpression, whereas that of the breast cancer-derived MDA-MB-231 cells was inhibited. Of note, in PDGFRL-overexpressing HCS-2/8 cells, the expression of chondrocyte differentiation marker genes, SOX9, ACAN, COL2A1, COL10A1, and ALP, was decreased. Moreover, we confirmed the expression of PDGFRL mRNA in normal cartilage tissue and chondrocytes. Eventually, the expression of PDGFRL mRNA in condrocytes except in the case of hypertrophic chondrocytes was demonstrated in vivo and in vitro. These findings suggest that PDGFRL plays the different roles, depending upon cell types. Particularly, in chondrocytes, PDGFRL may play a new and important role which is distinct from the function previously reported. J. Cell. Biochem. 118: 4033-4044, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Stimulation of chondrocyte proliferation following photothermal, thermal, and mechanical injury in ex-vivo cartilage grafts

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Pandoh, Nidhi S.; Truong, Mai T.; Diaz-Valdes, Sergio H.; Gardiner, David M.; Wong, Brian J.

2002-06-01

Laser irradiation may stimulate chondrocytes proliferation in the peripheral region surrounding a photothermally-heated area in rabbit nasal septal cartilage. In this study, ex- vivo rabbit nasal septal cartilages maintained in culture were irradiated with an Nd:YAG laser ((lambda) equals1.32 micrometers , 4-16 sec, 10-45 W/cm2) to examine the relationship between the diameter of replicating cells and irradiation time. Also, this study investigated whether proliferation occurs following heating (by immersion in hot saline baths, with a heated metal rod, and a soldering iron) and mechanical modification (crushing with a metal stamp and scoring with a scalpel). Replicating chondrocytes were identified using a Bromodeoxyuridine (BrdU) double antibody detection system in whole mount tissue. Light microscopy was used to confirm the presence of BrdU stained chondrocytes. The mechanical and thermal stressors used failed to produce a proliferative response in chondrocytes as previously seen with laser irradiation. We suspect that chondrocyte proliferation may be induced as a response to alteration in matrix structure produced by photothermal, thermal, or mechanical modification of the matrix. Heat generated by a laser to stimulate chondrocyte proliferation may lead to new treatment options for degenerative articular diseases and disorders. Laser technology can be adapted for use with minimally invasive surgical instrumentation to deliver light into otherwise inaccessible regions of the body.

CARTILAGE CONSTRUCTS ENGINEERED FROM CHONDROCYTES OVEREXPRESSING IGF-I IMPROVE THE REPAIR OF OSTEOCHONDRAL DEFECTS IN A RABBIT MODEL

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Madry, Henning; Kaul, Gunter; Zurakowski, David; Vunjak-Novakovic, Gordana; Cucchiarini, Magali

2015-01-01

Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes over expressing a human insulin-like growth factor I (IGF-I) gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-over expressing chondrocytes markedly improved osteochondral repair compared with control (lacZ) constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects. PMID:23588785

Cartilage constructs engineered from chondrocytes overexpressing IGF-I improve the repair of osteochondral defects in a rabbit model

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H Madry

2013-04-01

Full Text Available Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes overexpressing a human insulin-like growth factor I (IGF-I gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-overexpressing chondrocytes markedly improved osteochondral repair compared with control (lacZ constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects.

The distribution of YKL-40 in osteoarthritic and normal human articular cartilage

DEFF Research Database (Denmark)

Volck, B; Ostergaard, K; Johansen, J S

1999-01-01

YKL-40, also called human cartilage glycoprotein-39, is a major secretory protein of human chondrocytes in cell culture. YKL-40 mRNA is expressed by cartilage from patients with rheumatoid arthritis, but is not detectable in normal human cartilage. The aim was to investigate the distribution of YKL......-40 in osteoarthritic (n=9) and macroscopically normal (n=5) human articular cartilage, collected from 12 pre-selected areas of the femoral head, to discover a potential role for YKL-40 in cartilage remodelling in osteoarthritis. Immunohistochemical analysis showed that YKL-40 staining was found...... in chondrocytes of osteoarthritic cartilage mainly in the superficial and middle zone of the cartilage rather than the deep zone. There was a tendency for high number of YKL-40 positive chondrocytes in areas of the femoral head with a considerable biomechanical load. The number of chondrocytes with a positive...

Smad signaling pathway is a pivotal component of tissue inhibitor of metalloproteinases-3 regulation by transforming growth factor beta in human chondrocytes.

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Qureshi, Hamid Yaqoob; Ricci, Gemma; Zafarullah, Muhammad

2008-09-01

Transforming growth factor beta (TGF-beta1) promotes cartilage matrix synthesis and induces tissue inhibitor of metalloproteinases-3 (TIMP-3), which inhibits matrix metalloproteinases, aggrecanases and TNF-alpha-converting enzyme implicated in articular cartilage degradation and joint inflammation. TGF-beta1 activates Akt, ERK and Smad2 pathways in chondrocytes. Here we investigated previously unexplored roles of specific Smads in TGF-beta1 induction of TIMP-3 gene by pharmacological and genetic knockdown approaches. TGF-beta1-induced Smad2 phosphorylation and TIMP-3 protein expression could be inhibited by the Smad2/3 phosphorylation inhibitors, PD169316 and SB203580 and by Smad2-specific siRNA. Specific inhibitor of Smad3 (SIS3) and Smad3 siRNA abolished TGF-beta induction of TIMP-3. Smad2/3 siRNAs also down regulated TIMP-3 promoter-driven luciferase activities, suggesting transcriptional regulation. SiRNA-driven co-Smad4 knockdown abrogated TIMP-3 augmentation by TGF-beta. TIMP-3 promoter deletion analysis revealed that -828 deletion retains the original promoter activity while -333 and -167 deletions display somewhat reduced activity suggesting that most of the TGF-beta-responsive, cis-acting elements are found in the -333 fragment. Chromatin Immunoprecipitation (ChIP) analysis confirmed binding of Smad2 and Smad4 with the -940 and -333 promoter sequences. These results suggest that receptor-activated Smad2 and Smad3 and co-Smad4 critically mediate TGF-beta-stimulated TIMP-3 expression in human chondrocytes and TIMP-3 gene is a target of Smad signaling pathway.

Study on the effects of gradient mechanical pressures on the proliferation, apoptosis, chondrogenesis and hypertrophy of mandibular condylar chondrocytes in vitro.

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Li, Hui; Huang, Linjian; Xie, Qianyang; Cai, Xieyi; Yang, Chi; Wang, Shaoyi; Zhang, Min

2017-01-01

To investigate the effects of gradient mechanical pressure on chondrocyte proliferation, apoptosis, and the expression of markers of chondrogenesis and chondrocyte hypertrophy. Mandibular condylar chondrocytes from 5 rabbits were cultured in vitro, and pressed with static pressures of 50kPa, 100kPa, 150kPa and 200kPa for 3h, respectively. The chondrocytes cultured without pressure (0kPa) were used as control. Cell proliferation, apoptosis, and the expression of aggrecan (AGG), collagen II (COL2), collagen X (COL10), alkaline phosphatase (ALP) were investigated. Ultrastructures of the pressurized chondrocytes under transmission electron microscopy (TEM) were observed. Chondrocyte proliferation increased at 100kPa and decreased at 200kPa. Chondrocyte apoptosis increased with peak pressure at 200kPa in a dose-dependent manner. Chondrocyte necrosis increased at 200kPa. The expression of AGG increased at 200kPa. The expression of COL2 decreased at 50kPa and increased at 150kPa. The expression of COL10 and ALP increased at 150kPa. Ultrastructure of the pressurized chondrocytes under TEM showed: at 100kPa, cells were enlarged with less cellular microvillus and a bigger nucleus; at 200kPa, cells shrank with the sign of apoptosis, and apoptosis cells were found. The mechanical loading of 150kPa is the moderate pressure for chondrocyte: cell proliferation and apoptosis is balanced, necrosis is reduced, and chondrogenesis and chondrocyte hypertrophy are promoted. When the pressure is lower, chondrogenesis and chondrocyte hypertrophy are inhibited. At 200kPa, degeneration of cartilage is implied. Copyright © 2016 Elsevier Ltd. All rights reserved.

Visualization of living terminal hypertrophic chondrocytes of growth plate cartilage in situ by differential interference contrast microscopy and time-lapse cinematography.

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Farnum, C E; Turgai, J; Wilsman, N J

1990-09-01

The functional unit within the growth plate consists of a column of chondrocytes that passes through a sequence of phases including proliferation, hypertrophy, and death. It is important to our understanding of the biology of the growth plate to determine if distal hypertrophic cells are viable, highly differentiated cells with the potential of actively controlling terminal events of endochondral ossification prior to their death at the chondro-osseous junction. This study for the first time reports on the visualization of living hypertrophic chondrocytes in situ, including the terminal hypertrophic chondrocyte. Chondrocytes in growth plate explants are visualized using rectified differential interference contrast microscopy. We record and measure, using time-lapse cinematography, the rate of movement of subcellular organelles at the limit of resolution of this light microscopy system. Control experiments to assess viability of hypertrophic chondrocytes include coincubating organ cultures with the intravital dye fluorescein diacetate to assess the integrity of the plasma membrane and cytoplasmic esterases. In this system, all hypertrophic chondrocytes, including the very terminal chondrocyte, exist as rounded, fully hydrated cells. By the criteria of intravital dye staining and organelle movement, distal hypertrophic chondrocytes are identical to chondrocytes in the proliferative and early hypertrophic cell zones.

Investigation of the Effects of Extracellular Osmotic Pressure on Morphology and Mechanical Properties of Individual Chondrocyte.

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Nguyen, Trung Dung; Oloyede, Adekunle; Singh, Sanjleena; Gu, YuanTong

2016-06-01

It has been demonstrated that most cells of the body respond to osmotic pressure in a systematic manner. The disruption of the collagen network in the early stages of osteoarthritis causes an increase in water content of cartilage which leads to a reduction of pericellular osmolality in chondrocytes distributed within the extracellular environment. It is therefore arguable that an insight into the mechanical properties of chondrocytes under varying osmotic pressure would provide a better understanding of chondrocyte mechanotransduction and potentially contribute to knowledge on cartilage degeneration. In this present study, the chondrocyte cells were exposed to solutions with different osmolality. Changes in their dimensions and mechanical properties were measured over time. Atomic force microscopy (AFM) was used to apply load at various strain-rates and the force-time curves were logged. The thin-layer elastic model was used to extract the elastic stiffness of chondrocytes at different strain-rates and at different solution osmolality. In addition, the porohyperelastic (PHE) model was used to investigate the strain-rate-dependent responses under the loading and osmotic pressure conditions. The results revealed that the hypo-osmotic external environment increased chondrocyte dimensions and reduced Young's modulus of the cells at all strain-rates tested. In contrast, the hyper-osmotic external environment reduced dimensions and increased Young's modulus. Moreover, using the PHE model coupled with inverse FEA simulation, we established that the hydraulic permeability of chondrocytes increased with decreasing extracellular osmolality which is consistent with previous work in the literature. This could be due to a higher intracellular fluid volume fraction with lower osmolality.

Can microcarrier-expanded chondrocytes synthesize cartilaginous tissue in vitro?

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Surrao, Denver C; Khan, Aasma A; McGregor, Aaron J; Amsden, Brian G; Waldman, Stephen D

2011-08-01

Tissue engineering is a promising approach for articular cartilage repair; however, it is challenging to produce adequate amounts of tissue in vitro from the limited number of cells that can be extracted from an individual. Relatively few cell expansion methods exist without the problems of de-differentiation and/or loss of potency. Recently, however, several studies have noted the benefits of three-dimensional (3D) over monolayer expansion, but the ability of 3D expanded chondrocytes to synthesize cartilaginous tissue constructs has not been demonstrated. Thus, the purpose of this study was to compare the properties of engineered cartilage constructs from expanded cells (monolayer and 3D microcarriers) to those developed from primary chondrocytes. Isolated bovine chondrocytes were grown for 3 weeks in either monolayer (T-Flasks) or 3D microcarrier (Cytodex 3) expansion culture. Expanded and isolated primary cells were then seeded in high density culture on Millicell™ filters for 4 weeks to evaluate the ability to synthesize cartilaginous tissue. While microcarrier expansion was twice as effective as monolayer expansion (microcarrier: 110-fold increase, monolayer: 52-fold increase), the expanded cells (monolayer and 3D microcarrier) were not effectively able to synthesize cartilaginous tissue in vitro. Tissues developed from primary cells were substantially thicker and accumulated significantly more extracellular matrix (proteoglycan content: 156%-292% increase; collagen content: 70%-191% increase). These results were attributed to phenotypic changes experienced during the expansion phase. Monolayer expanded chondrocytes lost their native morphology within 1 week, whereas microcarrier-expanded cells were spreading by 3 weeks of expansion. While the use of 3D microcarriers can lead to large cellular yields, preservation of chondrogenic phenotype during expansion is required in order to synthesize cartilaginous tissue.

SOX9 governs differentiation stage-specific gene expression in growth plate chondrocytes via direct concomitant transactivation and repression.

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Victor Y L Leung

2011-11-01

Full Text Available Cartilage and endochondral bone development require SOX9 activity to regulate chondrogenesis, chondrocyte proliferation, and transition to a non-mitotic hypertrophic state. The restricted and reciprocal expression of the collagen X gene, Col10a1, in hypertrophic chondrocytes and Sox9 in immature chondrocytes epitomise the precise spatiotemporal control of gene expression as chondrocytes progress through phases of differentiation, but how this is achieved is not clear. Here, we have identified a regulatory element upstream of Col10a1 that enhances its expression in hypertrophic chondrocytes in vivo. In immature chondrocytes, where Col10a1 is not expressed, SOX9 interacts with a conserved sequence within this element that is analogous to that within the intronic enhancer of the collagen II gene Col2a1, the known transactivation target of SOX9. By analysing a series of Col10a1 reporter genes in transgenic mice, we show that the SOX9 binding consensus in this element is required to repress expression of the transgene in non-hypertrophic chondrocytes. Forced ectopic Sox9 expression in hypertrophic chondrocytes in vitro and in mice resulted in down-regulation of Col10a1. Mutation of a binding consensus motif for GLI transcription factors, which are the effectors of Indian hedgehog signaling, close to the SOX9 site in the Col10a1 regulatory element, also derepressed transgene expression in non-hypertrophic chondrocytes. GLI2 and GLI3 bound to the Col10a1 regulatory element but not to the enhancer of Col2a1. In addition to Col10a1, paired SOX9-GLI binding motifs are present in the conserved non-coding regions of several genes that are preferentially expressed in hypertrophic chondrocytes and the occurrence of pairing is unlikely to be by chance. We propose a regulatory paradigm whereby direct concomitant positive and negative transcriptional control by SOX9 ensures differentiation phase-specific gene expression in chondrocytes. Discrimination between

Mechanical and hypoxia stress can cause chondrocytes apoptosis through over-activation of endoplasmic reticulum stress.

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Huang, Ziwei; Zhou, Min; Wang, Qian; Zhu, Mengjiao; Chen, Sheng; Li, Huang

2017-12-01

To examine the role of mechanical force and hypoxia on chondrocytes apoptosis and osteoarthritis (OA)-liked pathological change on mandibular cartilage through over-activation of endoplasmic reticulum stress (ERS). We used two in vitro models to examine the effect of mechanical force and hypoxia on chondrocytes apoptosis separately. The mandibular condylar chondrocytes were obtained from three-week-old male Sprague-Dawley rats. Flexcell 5000T apparatus was used to produce mechanical forces (12%, 0.5Hz, 24h vs 20%, 0.5Hz, 24h) on chondrocytes. For hypoxia experiment, the concentration of O 2 was down regulated to 5% or 1%. Cell apoptosis rates were quantified by annexin V and propidium iodide (PI) double staining and FACS analysis. Quantitative real-time PCR and western blot were performed to evaluate the activation of ERS and cellular hypoxia. Then we used a mechanical stress loading rat model to verify the involvement of ERS in OA-liked mandibular cartilage pathological change. Histological changes in mandibular condylar cartilage were assessed via hematoxylin & eosin (HE) staining. Immunohistochemistry of GRP78, GRP94, HIF-1α, and HIF-2α were performed to evaluate activation of the ERS and existence of hypoxia. Apoptotic cells were detected by the TUNEL method. Tunicamycin, 20% mechanical forces and hypoxia (1% O 2 ) all significantly increased chondrocytes apoptosis rates and expression of ERS markers (GRP78, GRP94 and Caspase 12). However, 12% mechanical forces can only increase the apoptotic sensitivity of chondrocytes. Mechanical stress resulted in OA-liked pathological change on rat mandibular condylar cartilage which included thinning cartilage and bone erosion. The number of apoptotic cells increased. ERS and hypoxia markers expressions were also enhanced. Salubrinal, an ERS inhibitor, can reverse these effects in vitro and in vivo through the down-regulation of ERS markers and hypoxia markers. We confirmed that mechanical stress and local hypoxia both

Lipofection of rabbit chondrocytes and long lasting expression of a lacZ reporter system in alginate beads.

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Stöve, J; Fiedler, J; Huch, K; Günther, K-P; Puhl, W; Brenner, R

2002-03-01

Our aim was to investigate the maintenance of the transfection status of non-viral transfected chondrocytes in an alginate culture system. Chondrocytes harvested from rabbit knees were isolated by sequential digestion and cultivated in monolayer culture. At 60-70% cell density, chondrocytes were transfected with different transfection systems (FuGENE6, CaCl2, Lipofectin). A lac Z expression vector (pcDNA 3.1/Myc-His+ lacZ) was used as a reporter system. In order to improve transfection rates, hyaluronidase (4 U/ml) was used prior and during the transfection procedure. Thereafter, transfected cells were either kept in monolayer culture or embedded in alginate beads and kept in culture for up to the next 30 weeks. Transfection efficiency was maximal using FuGENE6TM/DNA at a ratio of 3:2 and hyaluronidase (4 U/ml). Transfection efficiency reached up to 40.8% (+/- 3.2%) after 36 h. In alginate beads lac Z positive cells declined to 8.5% +/- 3.3% after 4 weeks and to 4.6% +/- 3.2% after 12 weeks of culturing. After 30 weeks 3% of chondrocytes still expressed lac Z. In contrast, during culturing in monolayer, no lac Z expression was detectable after 4 weeks. Differentiation status of the chondrocytes was confirmed by histology and immunohistochemistry methods. After successful gene transfer to rabbit chondrocytes the alginate system made it possible to culture lipofected chondrocytes phenotypically stable. Genetically engineered chondrocytes express the lac Z reporter gene over a period of at least 30 weeks. This transfection and culture system provides a promising tool to further investigate the over-expression of growth factors and enzyme inhibitors. Copyright 2002 OsteoArthritis Research Society International.

RhoA activation and nuclearization marks loss of chondrocyte phenotype in crosstalk with Wnt pathway.

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Öztürk, Ece; Despot-Slade, Evelin; Pichler, Michael; Zenobi-Wong, Marcy

2017-11-15

De-differentiation comprises a major drawback for the use of autologous chondrocytes in cartilage repair. Here, we investigate the role of RhoA and canonical Wnt signaling in chondrocyte phenotype. Chondrocyte de-differentiation is accompanied by an upregulation and nuclear localization of RhoA. Effectors of canonical Wnt signaling including β-catenin and YAP/TAZ are upregulated in de-differentiating chondrocytes in a Rho-dependent manner. Inhibition of Rho activation with C3 transferase inhibits nuclear localization of RhoA, induces expression of chondrogenic markers on 2D and enhances the chondrogenic effect of 3D culturing. Upregulation of chondrogenic markers by Rho inhibition is accompanied by loss of canonical Wnt signaling markers in 3D or on 2D whereas treatment of chondrocytes with Wnt-3a abrogates this effect. However, induction of canonical Wnt signaling inhibits chondrogenic markers on 2D but enhances chondrogenic re-differentiation on 2D with C3 transferase or in 3D. These data provide insights on the context-dependent role of RhoA and Wnt signaling in de-differentiation and on mechanisms to induce chondrogenic markers for therapeutic approaches. Copyright © 2017 Elsevier Inc. All rights reserved.

TGF-β2 is involved in the preservation of the chondrocyte phenotype under hypoxic conditions

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Das, R.; Timur, U. T.; Edip, S.; Haak, E.; Wruck, C.; Weinans, H.; Jahr, H.

2015-01-01

Culturing chondrocytes under oxygen tension closely resembling their in vivo environment has been shown to have positive effects on matrix synthesis. In redifferentiation of expanded chondrocytes, hypoxia increased collagen type II expression. However, the mechanism by which hypoxia enhances

Articular chondrocyte network mediated by gap junctions: role in metabolic cartilage homeostasis

Science.gov (United States)

Mayan, Maria D; Gago-Fuentes, Raquel; Carpintero-Fernandez, Paula; Fernandez-Puente, Patricia; Filgueira-Fernandez, Purificacion; Goyanes, Noa; Valiunas, Virginijus; Brink, Peter R; Goldberg, Gary S; Blanco, Francisco J

2017-01-01

Objective This study investigated whether chondrocytes within the cartilage matrix have the capacity to communicate through intercellular connections mediated by voltage-gated gap junction (GJ) channels. Methods Frozen cartilage samples were used for immunofluorescence and immunohistochemistry assays. Samples were embedded in cacodylate buffer before dehydration for scanning electron microscopy. Co-immunoprecipitation experiments and mass spectrometry (MS) were performed to identify proteins that interact with the C-terminal end of Cx43. GJ communication was studied through in situ electroporation, electrophysiology and dye injection experiments. A transwell layered culture system and MS were used to identify and quantify transferred amino acids. Results Microscopic images revealed the presence of multiple cellular projections connecting chondrocytes within the matrix. These projections were between 5 and 150 μm in length. MS data analysis indicated that the C-terminus of Cx43 interacts with several cytoskeletal proteins implicated in Cx trafficking and GJ assembly, including α-tubulin and β-tubulin, actin, and vinculin. Electrophysiology experiments demonstrated that 12-mer oligonucleotides could be transferred between chondrocytes within 12 min after injection. Glucose was homogeneously distributed within 22 and 35 min. No transfer was detected when glucose was electroporated into A549 cells, which have no GJs. Transwell layered culture systems coupled with MS analysis revealed connexins can mediate the transfer of L-lysine and L-arginine between chondrocytes. Conclusions This study reveals that intercellular connections between chondrocytes contain GJs that play a key role in cell-cell communication and a metabolic function by exchange of nutrients including glucose and essential amino acids. A three-dimensional cellular network mediated through GJs might mediate metabolic and physiological homeostasis to maintain cartilage tissue. PMID:24225059

Effect of ceramic calcium-phosphorus ratio on chondrocyte-mediated biosynthesis and mineralization.

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Boushell, Margaret K; Khanarian, Nora T; LeGeros, Raquel Z; Lu, Helen H

2017-10-01

The osteochondral interface functions as a structural barrier between cartilage and bone, maintaining tissue integrity postinjury and during homeostasis. Regeneration of this calcified cartilage region is thus essential for integrative cartilage healing, and hydrogel-ceramic composite scaffolds have been explored for calcified cartilage formation. The objective of this study is to test the hypothesis that Ca/P ratio of the ceramic phase of the composite scaffold regulates chondrocyte biosynthesis and mineralization potential. Specifically, the response of deep zone chondrocytes to two bioactive ceramics with different calcium-phosphorus ratios (1.35 ± 0.01 and 1.41 ± 0.02) was evaluated in agarose hydrogel scaffolds over two weeks in vitro. It was observed that the ceramic with higher calcium-phosphorus ratio enhanced chondrocyte proliferation, glycosaminoglycan production, and induced an early onset of alkaline phosphorus activity, while the ceramic with lower calcium-phosphorus ratio performed similarly to the ceramic-free control. These results underscore the importance of ceramic bioactivity in directing chondrocyte response, and demonstrate that Ca/P ratio is a key parameter to be considered in osteochondral scaffold design. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2694-2702, 2017. © 2017 Wiley Periodicals, Inc.

Evolution of Autologous Chondrocyte Repair and Comparison to Other Cartilage Repair Techniques

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Ashvin K. Dewan

2014-01-01

Full Text Available Articular cartilage defects have been addressed using microfracture, abrasion chondroplasty, or osteochondral grafting, but these strategies do not generate tissue that adequately recapitulates native cartilage. During the past 25 years, promising new strategies using assorted scaffolds and cell sources to induce chondrocyte expansion have emerged. We reviewed the evolution of autologous chondrocyte implantation and compared it to other cartilage repair techniques. Methods. We searched PubMed from 1949 to 2014 for the keywords “autologous chondrocyte implantation” (ACI and “cartilage repair” in clinical trials, meta-analyses, and review articles. We analyzed these articles, their bibliographies, our experience, and cartilage regeneration textbooks. Results. Microfracture, abrasion chondroplasty, osteochondral grafting, ACI, and autologous matrix-induced chondrogenesis are distinguishable by cell source (including chondrocytes and stem cells and associated scaffolds (natural or synthetic, hydrogels or membranes. ACI seems to be as good as, if not better than, microfracture for repairing large chondral defects in a young patient’s knee as evaluated by multiple clinical indices and the quality of regenerated tissue. Conclusion. Although there is not enough evidence to determine the best repair technique, ACI is the most established cell-based treatment for full-thickness chondral defects in young patients.

Xiphoid Process-Derived Chondrocytes: A Novel Cell Source for Elastic Cartilage Regeneration

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Nam, Seungwoo; Cho, Wheemoon; Cho, Hyunji; Lee, Jungsun

2014-01-01

Reconstruction of elastic cartilage requires a source of chondrocytes that display a reliable differentiation tendency. Predetermined tissue progenitor cells are ideal candidates for meeting this need; however, it is difficult to obtain donor elastic cartilage tissue because most elastic cartilage serves important functions or forms external structures, making these tissues indispensable. We found vestigial cartilage tissue in xiphoid processes and characterized it as hyaline cartilage in the proximal region and elastic cartilage in the distal region. Xiphoid process-derived chondrocytes (XCs) showed superb in vitro expansion ability based on colony-forming unit fibroblast assays, cell yield, and cumulative cell growth. On induction of differentiation into mesenchymal lineages, XCs showed a strong tendency toward chondrogenic differentiation. An examination of the tissue-specific regeneration capacity of XCs in a subcutaneous-transplantation model and autologous chondrocyte implantation model confirmed reliable regeneration of elastic cartilage regardless of the implantation environment. On the basis of these observations, we conclude that xiphoid process cartilage, the only elastic cartilage tissue source that can be obtained without destroying external shape or function, is a source of elastic chondrocytes that show superb in vitro expansion and reliable differentiation capacity. These findings indicate that XCs could be a valuable cell source for reconstruction of elastic cartilage. PMID:25205841

High throughput generated micro-aggregates of chondrocytes stimulate cartilage formation in vitro and in vivo

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Moreira Teixeira, Liliana; Leijten, Jeroen Christianus Hermanus; Sobral, J.; Jin, R.; van Apeldoorn, Aart A.; Feijen, Jan; van Blitterswijk, Clemens; Dijkstra, Pieter J.; Karperien, Hermanus Bernardus Johannes

2012-01-01

Cell-based cartilage repair strategies such as matrix-induced autologous chondrocyte implantation (MACI) could be improved by enhancing cell performance. We hypothesised that micro-aggregates of chondrocytes generated in high-throughput prior to implantation in a defect could stimulate cartilaginous

Targeted Deletion of Autophagy Genes Atg5 or Atg7 in the Chondrocytes Promotes Caspase-Dependent Cell Death and Leads to Mild Growth Retardation.

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Vuppalapati, Karuna K; Bouderlique, Thibault; Newton, Phillip T; Kaminskyy, Vitaliy O; Wehtje, Henrik; Ohlsson, Claes; Zhivotovsky, Boris; Chagin, Andrei S

2015-12-01

Longitudinal bone growth takes place in epiphyseal growth plates located in the ends of long bones. The growth plate consists of chondrocytes traversing from the undifferentiated (resting zone) to the terminally differentiated (hypertrophic zone) stage. Autophagy is an intracellular catabolic process of lysosome-dependent recycling of intracellular organelles and protein complexes. Autophagy is activated during nutritionally depleted or hypoxic conditions in order to facilitate cell survival. Chondrocytes in the middle of the growth plate are hypoxic and nutritionally depleted owing to the avascular nature of the growth plate. Accordingly, autophagy may facilitate their survival. To explore the role of autophagy in chondrocyte survival and constitutional bone growth, we generated mice with cartilage-specific ablation of either Atg5 (Atg5cKO) or Atg7 (Atg7cKO) by crossing Atg5 or Atg7 floxed mice with cartilage-specific collagen type 2 promoter-driven Cre. Both Atg5cKO and Atg7cKO mice showed growth retardation associated with enhanced chondrocyte cell death and decreased cell proliferation. Similarly, inhibition of autophagy by Bafilomycin A1 (Baf) or 3-methyladenine (3MA) promoted cell death in cultured slices of human growth plate tissue. To delineate the underlying mechanisms we employed ex vivo cultures of mouse metatarsal bones and RCJ3.IC5.18 rat chondrogenic cell line. Baf or 3MA impaired metatarsal bone growth associated with processing of caspase-3 and massive cell death. Similarly, treatment of RCJ3.IC5.18 chondrogenic cells by Baf also showed massive cell death and caspase-3 cleavage. This was associated with activation of caspase-9 and cytochrome C release. Altogether, our data suggest that autophagy is important for chondrocyte survival, and inhibition of this process leads to stunted growth and caspase-dependent death of chondrocytes. © 2015 American Society for Bone and Mineral Research.

Nuclear deformation and expression change of cartilaginous genes during in vitro expansion of chondrocytes

International Nuclear Information System (INIS)

Hoshiba, Takashi; Yamada, Tomoe; Lu, Hongxu; Kawazoe, Naoki; Tateishi, Tetsuya; Chen, Guoping

2008-01-01

Cartilaginous gene expression decreased when chondrocytes were expanded on cell-culture plates. Understanding the dedifferentiation mechanism may provide valuable insight into cartilage tissue engineering. Here, we demonstrated the relationship between the nuclear shape and gene expression during in vitro expansion culture of chondrocytes. Specifically, the projected nuclear area increased and cartilaginous gene expressions decreased during in vitro expansion culture. When the nuclear deformation was recovered by cytochalasin D treatment, aggrecan expression was up-regulated and type I collagen (Col1a2) expression was down-regulated. These results suggest that nuclear deformation may be one of the mechanisms for chondrocyte dedifferentiation during in vitro expansion culture

Lactoferrin inhibits dexamethasone-induced chondrocyte impairment from osteoarthritic cartilage through up-regulation of extracellular signal-regulated kinase 1/2 and suppression of FASL, FAS, and Caspase 3

International Nuclear Information System (INIS)

Tu, Yihui; Xue, Huaming; Francis, Wendy; Davies, Andrew P.; Pallister, Ian; Kanamarlapudi, Venkateswarlu; Xia, Zhidao

2013-01-01

Highlights: •Dex exerts dose-dependant inhibition of HACs viability and induction of apoptosis. •Dex-induced impairment of chondrocytes was attenuated by rhLF. •ERK and FASL/FAS signaling are involved in the effects of rhLF. •OA patients with glucocorticoid-induced cartilage damage may benefit from treatment with rhLF. -- Abstract: Dexamethasone (Dex) is commonly used for osteoarthritis (OA) with excellent anti-inflammatory and analgesic effect. However, Dex also has many side effects following repeated use over prolonged periods mainly through increasing apoptosis and inhibiting proliferation. Lactoferrin (LF) exerts significantly anabolic effect on many cells and little is known about its effect on OA chondrocytes. Therefore, the aim of this study is to investigate whether LF can inhibit Dex-induced OA chondrocytes apoptosis and explore its possible molecular mechanism involved in. MTT assay was used to determine the optimal concentration of Dex and recombinant human LF (rhLF) on chondrocytes at different time and dose points. Chondrocytes were then stimulated with Dex in the absence or presence of optimal concentration of rhLF. Cell proliferation and viability were evaluated using MTT and LIVE/DEAD assay, respectively. Cell apoptosis was evaluated by multi-parameter apoptosis assay kit using both confocal microscopy and flow cytometry, respectively. The expression of extracellular signal-regulated kinase (ERK), FAS, FASL, and Caspase-3 (CASP3) at the mRNA and protein levels were examined by real-time polymerase chain reaction (PCR) and immunocytochemistry, respectively. The optimal concentration of Dex (25 μg/ml) and rhLF (200 μg/ml) were chosen for the following experiments. rhLF significantly reversed the detrimental effect of Dex on chondrocytes proliferation, viability, and apoptosis. In addition, rhLF significantly prevented Dex-induced down-regulation of ERK and up-regulation of FAS, FASL, and CASP3. These findings demonstrated that rhLF acts as

Lactoferrin inhibits dexamethasone-induced chondrocyte impairment from osteoarthritic cartilage through up-regulation of extracellular signal-regulated kinase 1/2 and suppression of FASL, FAS, and Caspase 3

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Tu, Yihui [Department of Orthopaedics, Yangpu District Central Hospital Affiliated to Tongji University School of Medicine, 450 Tengyue Road, Shanghai (China); Xue, Huaming [Department of Orthopaedics, Yangpu District Central Hospital Affiliated to Tongji University School of Medicine, 450 Tengyue Road, Shanghai (China); Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Francis, Wendy [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Davies, Andrew P. [Department of Orthopaedics and Trauma, Moriston Hospital, Swansea (United Kingdom); Pallister, Ian; Kanamarlapudi, Venkateswarlu [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Xia, Zhidao, E-mail: zhidao.xia@gmail.com [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom)

2013-11-08

Highlights: •Dex exerts dose-dependant inhibition of HACs viability and induction of apoptosis. •Dex-induced impairment of chondrocytes was attenuated by rhLF. •ERK and FASL/FAS signaling are involved in the effects of rhLF. •OA patients with glucocorticoid-induced cartilage damage may benefit from treatment with rhLF. -- Abstract: Dexamethasone (Dex) is commonly used for osteoarthritis (OA) with excellent anti-inflammatory and analgesic effect. However, Dex also has many side effects following repeated use over prolonged periods mainly through increasing apoptosis and inhibiting proliferation. Lactoferrin (LF) exerts significantly anabolic effect on many cells and little is known about its effect on OA chondrocytes. Therefore, the aim of this study is to investigate whether LF can inhibit Dex-induced OA chondrocytes apoptosis and explore its possible molecular mechanism involved in. MTT assay was used to determine the optimal concentration of Dex and recombinant human LF (rhLF) on chondrocytes at different time and dose points. Chondrocytes were then stimulated with Dex in the absence or presence of optimal concentration of rhLF. Cell proliferation and viability were evaluated using MTT and LIVE/DEAD assay, respectively. Cell apoptosis was evaluated by multi-parameter apoptosis assay kit using both confocal microscopy and flow cytometry, respectively. The expression of extracellular signal-regulated kinase (ERK), FAS, FASL, and Caspase-3 (CASP3) at the mRNA and protein levels were examined by real-time polymerase chain reaction (PCR) and immunocytochemistry, respectively. The optimal concentration of Dex (25 μg/ml) and rhLF (200 μg/ml) were chosen for the following experiments. rhLF significantly reversed the detrimental effect of Dex on chondrocytes proliferation, viability, and apoptosis. In addition, rhLF significantly prevented Dex-induced down-regulation of ERK and up-regulation of FAS, FASL, and CASP3. These findings demonstrated that rhLF acts as

Stress relaxation analysis of single chondrocytes using porohyperelastic model based on AFM experiments

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Trung Dung Nguyen

2014-01-01

Full Text Available Based on atomic force microscopytechnique, we found that the chondrocytes exhibits stress relaxation behavior. We explored the mechanism of this stress relaxation behavior and concluded that the intracellular fluid exuding out from the cells during deformation plays the most important role in the stress relaxation. We applied the inverse finite element analysis technique to determine necessary material parameters for porohyperelastic (PHE model to simulate stress relaxation behavior as this model is proven capable of capturing the non-linear behavior and the fluid-solid interaction during the stress relaxation of the single chondrocytes. It is observed that PHE model can precisely capture the stress relaxation behavior of single chondrocytes and would be a suitable model for cell biomechanics.

Comprehensive high-resolution genomic profiling and cytogenetics of human chondrocyte cultures by GTG-banding, locus-specific FISH, SKY and SNP array.

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Wallenborn, M; Petters, O; Rudolf, D; Hantmann, H; Richter, M; Ahnert, P; Rohani, L; Smink, J J; Bulwin, G C; Krupp, W; Schulz, R M; Holland, H

2018-04-23

In the development of cell-based medicinal products, it is crucial to guarantee that the application of such an advanced therapy medicinal product (ATMP) is safe for the patients. The consensus of the European regulatory authorities is: "In conclusion, on the basis of the state of art, conventional karyotyping can be considered a valuable and useful technique to analyse chromosomal stability during preclinical studies". 408 chondrocyte samples (84 monolayers and 324 spheroids) from six patients were analysed using trypsin-Giemsa staining, spectral karyotyping and fluorescence in situ hybridisation, to evaluate the genetic stability of an ATMP named Spherox®. Single nucleotide polymorphism (SNP) array analysis was performed on chondrocyte spheroids from five of the six donors. Applying this combination of techniques, the genetic analyses performed revealed no significant genetic instability until passage 3 in monolayer cells and interphase cells from spheroid cultures at different time points. Clonal occurrence of polyploid metaphases and endoreduplications were identified associated with prolonged cultivation time. Also, gonosomal losses were observed in chondrocyte spheroids, with increasing passage and duration of the differentiation phase. Interestingly, in one of the donors, chromosomal aberrations that are also described in extraskeletal myxoid chondrosarcoma were identified. The SNP array analysis exhibited chromosomal aberrations in two donors and copy neutral losses of heterozygosity regions in four donors. This study showed the necessity of combined genetic analyses at defined cultivation time points in quality studies within the field of cell therapy.

Biochemical alterations in inflammatory reactive chondrocytes: evidence for intercellular network communication

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Eva Skiöldebrand

2018-01-01

Full Text Available Chondrocytes are effectively involved in the pathophysiological processes of inflammation in joints. They form cellular processes in the superficial layer of the articular cartilage and form gap junction coupled syncytium to facilitate cell-to-cell communication. However, very little is known about their physiological cellular identity and communication. The aim with the present work is to evaluate the physiological behavior after stimulation with the inflammatory inducers interleukin-1β and lipopolysaccharide. The cytoskeleton integrity and intracellular Ca2+ release were assessed as indicators of inflammatory state. Cytoskeleton integrity was analyzed through cartilage oligomeric matrix protein and actin labeling with an Alexa 488-conjugated phalloidin probe. Ca2+ responses were assessed through the Ca2+ sensitive fluorophore Fura-2/AM. Western blot analyses of several inflammatory markers were performed. The results show reorganization of the actin filaments. Glutamate, 5-hydoxytryptamine, and ATP evoked intracellular Ca2+ release changed from single peaks to oscillations after inflammatory induction in the chondrocytes. The expression of toll-like receptor 4, the glutamate transporters GLAST and GLT-1, and the matrix metalloproteinase-13 increased. This work demonstrates that chondrocytes are a key part in conditions that lead to inflammation in the cartilage. The inflammatory inducers modulate the cytoskeleton, the Ca2+ signaling, and several inflammatory parameters. In conclusion, our data show that the cellular responses to inflammatory insults from healthy and inflammatory chondrocytes resemble those previously observed in astrocyte and cardiac fibroblasts networks.

Photobiostimulation on chondrocytes proliferation in different concentration of fetal bovine serum under low-level laser irradiation

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Zheng, Liqin; Wang, Yuhua; Qiu, Caimin; Chen, Jianlin; Yang, Hongqin; Zhang, Yanding; Xie, Shusen

2015-03-01

The aim of this in vitro study was to evaluate the influence of low-level laser irradiation (LLLI) on the chondrocytes proliferation cultured in different concentration of fetal bovine serum (FBS) using 658 nm, 785 nm and 830 nm diode lasers. The role of energy density (10-70 mJ·cm-2) on chondrocytes proliferation following irradiation with 658 nm laser for 2 days was firstly investigated to find out the best laser energy density. Then the effect of LLLI on the proliferation of chondrocytes cultured with fetal bovine serum at 0%, 2%, 5% and 10% was also evaluated. The results showed that there was no or little photobiostimulation on the proliferation of chondrocytes cultured with 0% FBS and 10% FBS; the cell proliferation at 2% and 5% FBS was significantly modulated by LLLI.

Incorporation of hyaluronic acid into collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis

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Tang Shunqing [Department of Biomedical Engineering, Jinan University, Guangzhou 510632 (China); Spector, Myron [Tissue Engineering, VA Boston Healthcare System, Boston, MA 02130 (United States)

2007-09-15

Hyaluronic acid (HA), a principal matrix molecule in many tissues, is present in high amounts in articular cartilage. HA contributes in unique ways to the physical behavior of the tissue, and has been shown to have beneficial effects on chondrocyte activity. The goal of this study was to incorporate graduated amounts of HA into type I collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis in vitro. The results demonstrated that the amount of contraction of HA/collagen scaffolds by adult canine articular chondrocytes increased with the HA content of the scaffolds. The greatest amount of chondrogenesis after two weeks was found in the scaffolds which had undergone the most contraction. HA can play a useful role in adjusting the mechanical behavior of tissue engineering scaffolds and chondrogenesis in chondrocyte-seeded scaffolds.

The in vitro biocompatibility of d-(+) raffinose modified chitosan: Two-dimensional and three-dimensional systems for culturing of horse articular chondrocytes.

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De Angelis, Elena; Ravanetti, Francesca; Martelli, Paolo; Cacchioli, Antonio; Ivanovska, Ana; Corradi, Attilio; Nasi, Sonia; Bianchera, Annalisa; Passeri, Benedetta; Canelli, Elena; Bettini, Ruggero; Borghetti, Paolo

2017-12-01

The present study investigated the biocompatibility of chitosan films and scaffolds modified with d-(+)raffinose and their capability to support the growth and maintenance of the differentiation of articular chondrocytes in vitro. Primary equine articular chondrocytes were cultured on films and scaffolds of modified d-(+) raffinose chitosan. Their behavior was compared to that of chondrocytes grown in conventional bi- and three-dimensional culture systems, such as micromasses and alginate beads. Chitosan films maintained the phenotype of differentiated chondrocytes (typical round morphology) and sustained the synthesis of cartilaginous extracellular matrix (ECM), even at 4weeks of culture. Indeed, starting from 2weeks of culture, chondrocytes seeded on chitosan scaffolds were able to penetrate the surface pores and to colonize the internal matrix. Moreover they produced ECM expressing the genes of typical chondrocytes differentiation markers such as collagen II and aggrecan. In conclusion, chitosan modified with d-raffinose represents an ideal support for chondrocyte adhesion, proliferation and for the maintenance of cellular phenotypic and genotypic differentiation. This novel biomaterial could potentially be a reliable support for the re-differentiation of dedifferentiated chondrocytes. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Effects of in vitro continuous passaging on the phenotype of mouse hyaline chondrocytes and the balance of the extra- cellular matrix].

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Linyi, Cai; Xiangli, Kong; Jing, Xie

2016-06-01

This study aimed to investigate the effects of in vitro continuous passaging on the morphological phenotype and differentiation characteristics of mouse hyaline chondrocytes, as well as on the balance of the extracellular matrix (ECM). Enzymatic digestion was conducted to isolate mouse hyaline chondrocytes, which expanded over five passages in vitro. Hematoxylin-eosin stain was used to show the changes in chondrocyte morphology. Semi-quantitative polymerase chain reaction was performed to analyze the mRNA changes in the marker genes, routine genes, matrix metalloproteinases (MMPs), and tissue inhibitors of MMPs (TIMPs) in chondrocytes. Zymography was carried out to elucidate changes in gelatinase activities. After continuous expansion in vitro, the morphology of round or polygonal chondrocytes changed to elongated and spindled shape. The expression of marker genes significantly decreased (P 0.05). Meanwhile, the ratio of MMPs/TIMPs was altered. At the protein level, the activities of gelatinases decreased after passaging, especially for P4 and P5 chondrocytes (P cartilage ECM became uncontrollable and led to the imbalance of ECM homeostasis. When hyaline chondrocytes are applied in research on relevant diseases or cartilage tissue engineering, P0-P2 chondrocytes should be used.

[Stimulation of maturing and terminal differentiation by concanavalin A in rabbit permanent chondrocyte cultures].

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Yan, W Q; Yang, T S; Hou, L Z; Susuki, F; Kato, Y

1994-12-01

The effect of concanavalin A (Con A) on maturing and terminal differentiation in permanent chondrocyte cultures were examined. Chondrocytes isolated from permanent cartilage were seeded at low density and grown in MEM medium containing 10% fetal bovine serum, 50 micrograms/ml of ascorbic acid and antibiotics, at 37 degrees C under 50% CO2 in air. At 0.3% of low serum concentration, addition of Con A to the culture medium increased by 3- to 4-fold the incorporation of [35S] sulfate into large chondroitin sulfate proteoglycan that characteristically found in cartilage. Chemical analysis showed a 4-fold increase in the accumulation of macromolecular containing hexuronic acid in Con A-maintained cultures. The effect of Con A on [35S]sulfate incorporation into proteoglycan was greater than that of various growth factor or hormones. Brief exposure of the permanent chondrocytes to Con A (5 micrograms/ml) for 24 hours and subsequent incubation in its absence for 5-10 days resulted in 10- to 100-fold increase in alkaline phosphatase and binding of 1.25 (OH)2 vitamin D3 to cells. Treatment with Con A also resulted in 10- to 20-fold increase in calcium content and 45Ca incorporation into insoluble material. Methyl-D-mannopyranoside reversed the effect of Con A on [35S]sulfate incorporation into proteoglycan and alkaline phosphatase activity. Since other lectins, such as wheat germ agglutinin, lentil lectin, phytohemagglutinin, Ulex europeasu agglutinin and garden pea lectin had been tested to have little effect on [35S]sulfate incorporation into proteoglycans and induction of alkaline phosphatase activity, the Con A action on chondrocytes seems specific. These results indicate that Con A is a potent modulator of differentiation of chondrocytes, which induces the onset on a maturing and a terminal differentiation in chondrocytes, leading to extensive calcification of the extracellular matrix.

Upregulation of matrix synthesis in chondrocyte-seeded agarose following sustained bi-axial cyclic loading

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Belinda Pingguan-Murphy

2012-08-01

Full Text Available OBJECTIVES: The promotion of extracellular matrix synthesis by chondrocytes is a requisite part of an effective cartilage tissue engineering strategy. The aim of this in vitro study was to determine the effect of bi-axial cyclic mechanical loading on cell proliferation and the synthesis of glycosaminoglycans by chondrocytes in threedimensional cultures. METHOD: A strain comprising 10% direct compression and 1% compressive shear was applied to bovine chondrocytes seeded in an agarose gel during two 12-hour conditioning periods separated by a 12-hour resting period. RESULTS: The bi-axial-loaded chondrocytes demonstrated a significant increase in glycosaminoglycan synthesis compared with samples exposed to uni-axial or no loading over the same period (p<0.05. The use of a free-swelling recovery period prior to the loading regime resulted in additional glycosaminoglycan production and a significant increase in DNA content (p<0.05, indicating cell proliferation. CONCLUSIONS: These results demonstrate that the use of a bi-axial loading regime results in increased matrix production compared with uni-axial loading.

Effect of Cyclic Dynamic Compressive Loading on Chondrocytes and Adipose-Derived Stem Cells Co-Cultured in Highly Elastic Cryogel Scaffolds

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Chih-Hao Chen

2018-01-01

Full Text Available In this study, we first used gelatin/chondroitin-6-sulfate/hyaluronan/chitosan highly elastic cryogels, which showed total recovery from large strains during repeated compression cycles, as 3D scaffolds to study the effects of cyclic dynamic compressive loading on chondrocyte gene expression and extracellular matrix (ECM production. Dynamic culture of porcine chondrocytes was studied at 1 Hz, 10% to 40% strain and 1 to 9 h/day stimulation duration, in a mechanical-driven multi-chamber bioreactor for 14 days. From the experimental results, we could identify the optimum dynamic culture condition (20% and 3 h/day to enhance the chondrocytic phenotype of chondrocytes from the expression of marker (Col I, Col II, Col X, TNF-α, TGF-β1 and IGF-1 genes by quantitative real-time polymerase chain reactions (qRT-PCR and production of ECM (GAGs and Col II by biochemical analysis and immunofluorescence staining. With up-regulated growth factor (TGF-β1 and IGF-1 genes, co-culture of chondrocytes with porcine adipose-derived stem cells (ASCs was employed to facilitate chondrogenic differentiation of ASCs during dynamic culture in cryogel scaffolds. By replacing half of the chondrocytes with ASCs during co-culture, we could obtain similar production of ECM (GAGs and Col II and expression of Col II, but reduced expression of Col I, Col X and TNF-α. Subcutaneous implantation of cells/scaffold constructs in nude mice after mono-culture (chondrocytes or ASCs or co-culture (chondrocytes + ASCs and subject to static or dynamic culture condition in vitro for 14 days was tested for tissue-engineering applications. The constructs were retrieved 8 weeks post-implantation for histological analysis by Alcian blue, Safranin O and Col II immunohistochemical staining. The most abundant ectopic cartilage tissue was found for the chondrocytes and chondrocytes + ASCs groups using dynamic culture, which showed similar neo-cartilage formation capability with half of the

Biocompatibility of Human Auricular Chondrocytes Cultured onto a Chitosan/Polyvynil Alcohol/Epichlorohydrin-Based Hydrogel for Tissue Engineering Application

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Melgarejo-Ramírez, Yaaziel; Sánchez-Sánchez, Roberto; García-Carvajal, Zaira; García-López, Julieta; Gutiérrez-Gómez, Claudia; Luna-Barcenas, Gabriel; Ibarra, Clemente; Velasquillo, Cristina

2014-01-01

Tissue engineering (TE) has become an alternative for auricular reconstruction based on the combination of cells, molecular signals and biomaterials. Scaffolds are biomaterials that provide structural support for cell attachment and subsequent tissue development. Ideally, a scaffold should have characteristics such as biocompatibility and bioactivity to adequate support cell functions. Our purpose was to evaluate biocompatibility of microtic auricular chondrocytes seeded onto a chitosan-polyv...

CCN2/CTGF is required for matrix organization and to protect growth plate chondrocytes from cellular stress.

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Hall-Glenn, Faith; Aivazi, Armen; Akopyan, Lusi; Ong, Jessica R; Baxter, Ruth R; Benya, Paul D; Goldschmeding, Roel; van Nieuwenhoven, Frans A; Hunziker, Ernst B; Lyons, Karen M

2013-08-01

CCN2 (connective tissue growth factor (CTGF/CCN2)) is a matricellular protein that utilizes integrins to regulate cell proliferation, migration and survival. The loss of CCN2 leads to perinatal lethality resulting from a severe chondrodysplasia. Upon closer inspection of Ccn2 mutant mice, we observed defects in extracellular matrix (ECM) organization and hypothesized that the severe chondrodysplasia caused by loss of CCN2 might be associated with defective chondrocyte survival. Ccn2 mutant growth plate chondrocytes exhibited enlarged endoplasmic reticula (ER), suggesting cellular stress. Immunofluorescence analysis confirmed elevated stress in Ccn2 mutants, with reduced stress observed in Ccn2 overexpressing transgenic mice. In vitro studies revealed that Ccn2 is a stress responsive gene in chondrocytes. The elevated stress observed in Ccn2-/- chondrocytes is direct and mediated in part through integrin α5. The expression of the survival marker NFκB and components of the autophagy pathway were decreased in Ccn2 mutant growth plates, suggesting that CCN2 may be involved in mediating chondrocyte survival. These data demonstrate that absence of a matricellular protein can result in increased cellular stress and highlight a novel protective role for CCN2 in chondrocyte survival. The severe chondrodysplasia caused by the loss of CCN2 may be due to increased chondrocyte stress and defective activation of autophagy pathways, leading to decreased cellular survival. These effects may be mediated through nuclear factor κB (NFκB) as part of a CCN2/integrin/NFκB signaling cascade.

Uptake of {sup 99m}Tc-labeled chondroitin sulfate by chondrocytes and cartilage: a promising agent for imaging of cartilage degeneration?

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Sobal, Grazyna [Department of Nuclear Medicine, Medical University of Vienna, Vienna 1090 (Austria)], E-mail: grazyna.sobal@meduniwien.ac.at; Menzel, Johannes [Institute of Immunology, Medical University of Vienna, Vienna 1090 (Austria); Sinzinger, Helmut [Department of Nuclear Medicine, Medical University of Vienna, Vienna 1090 (Austria)

2009-01-15

Chondroitin sulfate (CS) is used in the treatment of human osteoarthritis as a slow-acting symptomatic drug. For this reason, we performed uptake studies with {sup 99m}TcCS using different chondrocyte cultures, as well as cartilage tissue in vitro. For uptake studies, adherent monolayer cultures of human chondrocytes (2.7x10{sup 4} cells/well) and {sup 99m}TcCS (1 {mu}Ci) were used. In parallel, we also performed uptake studies with cell suspensions of human chondrocytes at 1x10{sup 6} cells/well incubated with {sup 99m}TcCS (5 {mu}Ci) under identical conditions. Uptake was studied also in cartilage tissue samples and frozen tissue sections for autoradiography. The uptake was monitored for 10-240 min, every 10-30 min for cell cultures and for cartilage tissue up to 72 h. As the commercially available drug Condrosulf (IBSA, Lugano, Switzerland) contains magnesium (Mg) stearate as additive, we investigated the uptake with and without this additive. The washout of the tracer was assessed after the uptake experiments with PBS buffer for different time intervals (10 min-3 h). Tracer uptake in monolayer{+-}additives with low number of cells was low. With the use of chondrocytes in culture suspensions with higher number of cells, a higher uptake of 5.9{+-}0.65% and 1.0{+-}0.1% (n=6) was found, with and without additive, respectively. The saturation was achieved after 100 min. With the use of human rib cartilage, the uptake of {sup 99m}TcCS was continuously increasing with time and was very high with additive amounting to 101.8{+-}5.2% vs. 53.0{+-}8.3% (n=6) without after 72 h and showing delayed saturation up to 30 h. Thus, not only the resorption of the drug is enhanced by Mg-stearate, but also the uptake. The washout of the tracer from cartilage after 3 h of uptake amounted to 3.75{+-}1.5% with additive vs. 13.1{+-}2.1% without. After 24 h, washout was lower amounting to 1.75{+-}0.15% vs. 3.25{+-}0.25%, respectively. The autoradiographic studies paralleled the results

Surviving endoplasmic reticulum stress is coupled to altered chondrocyte differentiation and function.

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Kwok Yeung Tsang

2007-03-01

Full Text Available In protein folding and secretion disorders, activation of endoplasmic reticulum (ER stress signaling (ERSS protects cells, alleviating stress that would otherwise trigger apoptosis. Whether the stress-surviving cells resume normal function is not known. We studied the in vivo impact of ER stress in terminally differentiating hypertrophic chondrocytes (HCs during endochondral bone formation. In transgenic mice expressing mutant collagen X as a consequence of a 13-base pair deletion in Col10a1 (13del, misfolded alpha1(X chains accumulate in HCs and elicit ERSS. Histological and gene expression analyses showed that these chondrocytes survived ER stress, but terminal differentiation is interrupted, and endochondral bone formation is delayed, producing a chondrodysplasia phenotype. This altered differentiation involves cell-cycle re-entry, the re-expression of genes characteristic of a prehypertrophic-like state, and is cell-autonomous. Concomitantly, expression of Col10a1 and 13del mRNAs are reduced, and ER stress is alleviated. ERSS, abnormal chondrocyte differentiation, and altered growth plate architecture also occur in mice expressing mutant collagen II and aggrecan. Alteration of the differentiation program in chondrocytes expressing unfolded or misfolded proteins may be part of an adaptive response that facilitates survival and recovery from the ensuing ER stress. However, the altered differentiation disrupts the highly coordinated events of endochondral ossification culminating in chondrodysplasia.

The Effect of Chondroitin Sulphate and Hyaluronic Acid on Chondrocytes Cultured within a Fibrin-Alginate Hydrogel

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Christopher J. Little

2014-09-01

Full Text Available Osteoarthritis is a painful degenerative joint disease that could be better managed if tissue engineers can develop methods to create long-term engineered articular cartilage tissue substitutes. Many of the tissue engineered cartilage constructs currently available lack the chemical stimuli and cell-friendly environment that promote the matrix accumulation and cell proliferation needed for use in joint cartilage repair. The goal of this research was to test the efficacy of using a fibrin-alginate hydrogel containing hyaluronic acid (HA and/or chondroitin sulphate (CS supplements for chondrocyte culture. Neonatal porcine chondrocytes cultured in fibrin-alginate hydrogels retained their phenotype better than chondrocytes cultured in monolayer, as evidenced by analysis of their relative expression of type II versus type I collagen mRNA transcripts. HA or CS supplementation of the hydrogels increased matrix glycosaminoglycan (GAG production during the first week of culture. However, the effects of these supplements on matrix accumulation were not additive and were no longer observed after two weeks of culture. Supplementation of the hydrogels with CS or a combination of both CS and HA increased the chondrocyte cell population after two weeks of culture. Statistical analysis indicated that the HA and CS treatment effects on chondrocyte numbers may be additive. This research suggests that supplementation with CS and/or HA has positive effects on cartilage matrix production and chondrocyte proliferation in three-dimensional (3D fibrin-alginate hydrogels.

Chondrocytes co-cultured with Stromal Vascular Fraction of adipose tissue present more intense chondrogenic characteristics than with Adipose Stem Cells

NARCIS (Netherlands)

Wu, Ling; Prins, H.J.; Leijten, Jeroen Christianus Hermanus; Helder, M.; Evseenko, D.; Moroni, L; van Blitterswijk, Clemens; Lin, Y.; Karperien, Hermanus Bernardus Johannes

2016-01-01

Partly replacement of chondrocytes by stem cells has been proposed to improve the performance of autologous chondrocytes implantation (ACI). Our previous studies showed that the increased cartilage production in pellet co-cultures of chondrocytes and mesenchymal stem cells (MSCs) is due to a trophic

Longitudinal bone growth is impaired by direct involvement of caffeine with chondrocyte differentiation in the growth plate.

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Choi, Hyeonhae; Choi, Yuri; Kim, Jisook; Bae, Jaeman; Roh, Jaesook

2017-01-01

We showed previously that caffeine adversely affects longitudinal bone growth and disrupts the histomorphometry of the growth plate during the pubertal growth spurt. However, little attention has been paid to the direct effects of caffeine on chondrocytes. Here, we investigated the direct effects of caffeine on chondrocytes of the growth plate in vivo and in vitro using a rapidly growing young rat model, and determined whether they were related to the adenosine receptor signaling pathway. A total of 15 male rats (21 days old) were divided randomly into three groups: a control group and two groups fed caffeine via gavage with 120 and 180 mg kg -1  day -1 for 4 weeks. After sacrifice, the tibia processed for the analysis of the long bone growth and proliferation of chondrocytes using tetracycline and BrdU incorporation, respectively. Caffeine-fed animals showed decreases in matrix mineralization and proliferation rate of growth plate chondrocytes compared with the control. To evaluate whether caffeine directly affects chondrocyte proliferation and chondrogenic differentiation, primary rat chondrocytes were isolated from the growth plates and cultured in either the presence or absence of caffeine at concentrations of 0.1-1 mm, followed by determination of the cellular proliferation or expression profiles of cellular differentiation markers. Caffeine caused significant decreases in extracellular matrix production, mineralization, and alkaline phosphatase activity, accompanied with decreases in gene expression of the cartilage-specific matrix proteins such as aggrecan, type II collagen and type X. Our results clearly demonstrate that caffeine is capable of interfering with cartilage induction by directly inhibiting the synthetic activity and orderly expression of marker genes relevant to chondrocyte maturation. In addition, we found that the adenosine type 1 receptor signaling pathway may be partly involved in the detrimental effects of caffeine on chondrogenic

[Study on the method of two dimensional polycrylamide gel electrophoresis on rat condylar chondrocyte].

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Wu, Tuo-jiang; Li, Huang; Ma, Qiao-lin; Wang, Wen-mei

2010-08-01

To investigate the protein profile by two dimensional polycrylamide gel electrophoresis on the rat condylar chondrocyte in vitro. The third-passage chondrocytes were harvested from the mandibular condyles of 2-day-old rats in this study. The protein profile of the rat mandibular condylar chondrocytes was examined by two dimensional polycrylamide gel electrophoresis (2-DE-PAGE). The 2-DE gel maps on different pH gradients were obtained. The result of modified coomassi blue-sliver staining and sliver staining was compared using Pdquest 7.1 image analysis software. The results showed that the good protein profile of the condylar chondrocytes was obtained by standard Bio-Rad manual. The protein was mainly in the field from pH4 to pH7. The 1203±86 protein points were examined on 2-DE gel map by modified coomassi blue-sliver staining, and 1769±97 protein points was examined by sliver staining. The silver staining map showed more distinctly but higher background than modified coomassi blue-sliver staining. The protein profile of the condylar chondrocytes enriches the proteomic database and gives evidence to further proteomic research. The 2-DE map obtained by modified coomassi blue-sliver staining is more suitable for MALDI-TOF mass identification. Supported by National Natural Science Foundation of China (Grant No. C30700963), China Postdoctoral Science Foundation(Grant No.20090461088), Jiangsu Provincial Postdoctoral Science Foundation (Grant No.0802003C) and Nanjing City's Science and Technology Foundation (Grant No.200905011).

The transcription factor ATF3 is upregulated during chondrocyte differentiation and represses cyclin D1 and A gene transcription

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James Claudine G

2006-09-01

Full Text Available Abstract Background Coordinated chondrocyte proliferation and differentiation are required for normal endochondral bone growth. Transcription factors binding to the cyclicAMP response element (CRE are known to regulate these processes. One member of this family, Activating Tanscription Factor 3 (ATF3, is expressed during skeletogenesis and acts as a transcriptional repressor, but the function of this protein in chondrogenesis is unknown. Results Here we demonstrate that Atf3 mRNA levels increase during mouse chondrocyte differentiation in vitro and in vivo. In addition, Atf3 mRNA levels are increased in response to cytochalasin D treatment, an inducer of chondrocyte maturation. This is accompanied by increased Atf3 promoter activity in cytochalasin D-treated chondrocytes. We had shown earlier that transcription of the cell cycle genes cyclin D1 and cyclin A in chondrocytes is dependent on CREs. Here we demonstrate that overexpression of ATF3 in primary mouse chondrocytes results in reduced transcription of both genes, as well as decreased activity of a CRE reporter plasmid. Repression of cyclin A transcription by ATF3 required the CRE in the cyclin A promoter. In parallel, ATF3 overexpression reduces the activity of a SOX9-dependent promoter and increases the activity of a RUNX2-dependent promoter. Conclusion Our data suggest that transcriptional induction of the Atf3 gene in maturing chondrocytes results in down-regulation of cyclin D1 and cyclin A expression as well as activation of RUNX2-dependent transcription. Therefore, ATF3 induction appears to facilitate cell cycle exit and terminal differentiation of chondrocytes.

Strategies on process engineering of chondrocyte culture for cartilage tissue regeneration.

Science.gov (United States)

Mallick, Sarada Prasanna; Rastogi, Amit; Tripathi, Satyavrat; Srivastava, Pradeep

2017-04-01

The current work is an attempt to study the strategies for cartilage tissue regeneration using porous scaffold in wavy walled airlift bioreactor (ALBR). Novel chitosan, poly (L-lactide) and hyaluronic acid based composite scaffold were prepared. The scaffolds were cross-linked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, N-hydroxysuccinimide and chondroitin sulfate to obtain interconnected 3D microstructure showing excellent biocompatibility, higher cellular differentiation and increased stability. The surface morphology and porosity of the scaffolds were analyzed using scanning electron microscopy (SEM) and mercury intrusion porosimeter and optimized for chondrocyte regeneration. The study shows that the scaffolds were highly porous with pore size ranging from 48 to 180 µm and the porosities in the range 80-92%. Swelling and in vitro degradation studies were performed for the composite scaffolds; by increasing the chitosan: HA ratio in the composite scaffolds, the swelling property increases and stabilizes after 24 h. There was controlled degradation of composite scaffolds for 4 weeks. The uniform chondrocyte distribution in the scaffold using various growth modes in the shake flask and ALBR was studied by glycosaminoglycans (GAG) quantification, MTT assay and mixing time evaluation. The cell culture studies demonstrated that efficient designing of ALBR increases the cartilage regeneration as compared to using a shake flask. The free chondrocyte microscopy and cell attachment were performed by inverted microscope and SEM, and from the study it was confirmed that the cells uniformly attached to the scaffold. This study focuses on optimizing strategies for the culture of chondrocyte using suitable scaffold for improved cartilage tissue regeneration.

Ectopic bone formation during tissue-engineered cartilage repair using autologous chondrocytes and novel plasma-derived albumin scaffolds.

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Robla Costales, David; Junquera, Luis; García Pérez, Eva; Gómez Llames, Sara; Álvarez-Viejo, María; Meana-Infiesta, Álvaro

2016-10-01

The aims of this study were twofold: first, to evaluate the production of cartilaginous tissue in vitro and in vivo using a novel plasma-derived scaffold, and second, to test the repair of experimental defects made on ears of New Zealand rabbits (NZr) using this approach. Scaffolds were seeded with chondrocytes and cultured in vitro for 3 months to check in vitro cartilage production. To evaluate in vivo cartilage production, a chondrocyte-seeded scaffold was transplanted subcutaneously to a nude mouse. To check in vivo repair, experimental defects made in the ears of five New Zealand rabbits (NZr) were filled with chondrocyte-seeded scaffolds. In vitro culture produced mature chondrocytes with no extracellular matrix (ECM). Histological examination of redifferentiated in vitro cultures showed differentiated chondrocytes adhered to scaffold pores. Subcutaneous transplantation of these constructs to a nude mouse produced cartilage, confirmed by histological study. Experimental cartilage repair in five NZr showed cartilaginous tissue repairing the defects, mixed with calcified areas of bone formation. It is possible to produce cartilaginous tissue in vivo and to repair experimental auricular defects by means of chondrocyte cultures and the novel plasma-derived scaffold. Further studies are needed to determine the significance of bone formation in the samples. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

The rate of hypo-osmotic challenge influences regulatory volume decrease (RVD) and mechanical properties of articular chondrocytes.

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Wang, Z; Irianto, J; Kazun, S; Wang, W; Knight, M M

2015-02-01

Osteoarthritis (OA) is associated with a gradual reduction in the interstitial osmotic pressure within articular cartilage. The aim of this study was to compare the effects of sudden and gradual hypo-osmotic challenge on chondrocyte morphology and biomechanics. Bovine articular chondrocytes were exposed to a reduction in extracellular osmolality from 327 to 153 mOsmol/kg applied either suddenly (osmotic stress, 66% of chondrocytes exhibited an increase in diameter followed by RVD, whilst 25% showed no RVD. By contrast, cells exposed to gradual hypo-osmotic stress exhibited reduced cell swelling without subsequent RVD. There was an increase in the equilibrium modulus for cells exposed to sudden hypo-osmotic stress. However, gradual hypo-osmotic challenge had no effect on cell mechanical properties. This cell stiffening response to sudden hypo-osmotic challenge was abolished when actin organization was disrupted with cytochalasin D or RVD inhibited with REV5901. Both sudden and gradual hypo-osmotic challenge reduced cortical F-actin distribution and caused chromatin decondensation. Sudden hypo-osmotic challenge increases chondrocyte mechanics by activation of RVD and interaction with the actin cytoskeleton. Moreover, the rate of hypo-osmotic challenge is shown to have a profound effect on chondrocyte morphology and biomechanics. This important phenomenon needs to be considered when studying the response of chondrocytes to pathological hypo-osmotic stress. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Melatonin protects chondrocytes from impairment induced by glucocorticoids via NAD+-dependent SIRT1.

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Yang, Wei; Kang, Xiaomin; Qin, Na; Li, Feng; Jin, Xinxin; Ma, Zhengmin; Qian, Zhuang; Wu, Shufang

2017-10-01

Intra-articular injection of glucocorticoids is used to relieve pain and inflammation in osteoarthritis patients, which is occasionally accompanied with the serious side effects of glucocorticoids in collagen-producing tissue. Melatonin is the major hormone released from the pineal gland and its beneficial effects on cartilage has been suggested. In the present study, we investigated the protective role of melatonin on matrix degeneration in chondrocytes induced by dexamethasone (Dex). The chondrocytes isolated from mice knee joint were treated with Dex, melatonin, EX527 and siRNA targeted for SIRT6, respectively. Dex treatment induced the loss of the extracellular matrix, NAD + /NADH ratio and NADPH concentration in chondrocytes. Melatonin alone have no effect on the quantity of proteoglycans and collagen type IIa1, however, the pretreatment of melatonin reversed the negative effects induced by Dex. Meanwhile, the significant decrease in NAD + /NADH ratio and NADPH concentration in Dex group were up-regulated by pretreatment of melatonin. Furthermore, it was revealed that inhibition of SIRT1 blocked the protective effects of melatonin. The enhancement of NAD + -dependent SIRT1 activity contributes to the chondroprotecfive effects of melatonin, which has a great benefit to prevent dexamethasone-induced chondrocytes impairment. Copyright © 2017 Elsevier Inc. All rights reserved.

The trans-well coculture of human synovial mesenchymal stem cells with chondrocytes leads to self-organization, chondrogenic differentiation, and secretion of TGFβ

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Kubosch, Eva Johanna; Heidt, Emanuel; Bernstein, Anke

2016-01-01

BACKGROUND: Synovial mesenchymal stem cells (SMSC) possess a high chondrogenic differentiation potential, which possibly supports natural and surgically induced healing of cartilage lesions. We hypothesized enhanced chondrogenesis of SMSC caused by the vicinity of chondrocytes (CHDR). METHODS...

Repair of experimentally produced defects in rabbit articular cartilage by autologous chondrocyte transplantation

International Nuclear Information System (INIS)

Grande, D.A.; Pitman, M.I.; Peterson, L.; Menche, D.; Klein, M.

1989-01-01

Using the knee joints of New Zealand White rabbits, a baseline study was made to determine the intrinsic capability of cartilage for healing defects that do not fracture the subchondral plate. A second experiment examined the effect of autologous chondrocytes grown in vitro on the healing rate of these defects. To determine whether any of the reconstituted cartilage resulted from the chondrocyte graft, a third experiment was conducted involving grafts with chondrocytes that had been labeled prior to grafting with a nuclear tracer. Results were evaluated using both qualitative and quantitative light microscopy. Macroscopic results from grafted specimens displayed a marked decrease in synovitis and other degenerative changes. In defects that had received transplants, a significant amount of cartilage was reconstituted (82%) compared to ungrafted controls (18%). Autoradiography on reconstituted cartilage showed that there were labeled cells incorporated into the repair matrix

The role of PTHrP in chondrocyte differentiation

NARCIS (Netherlands)

Hoogendam, Jakomijn

2006-01-01

Longitudinal growth is the key characteristic that distinguishes children from adults. Growth is regulated in the growth plates, which are layers of cartilage located at the ends of the long bones. The cartilage cells are called chondrocytes and go through a coordinated program of proliferation,

In vitro cell quality of articular chondrocytes assigned for autologous implantation in dependence of specific patient characteristics

DEFF Research Database (Denmark)

Pestka, Jan M; Schmal, Hagen; Salzmann, Gian

2011-01-01

OBJECTIVE: Autologous chondrocyte implantation (ACI) is a well-established therapeutic option for the treatment of cartilage defects of the knee joint. Since information concerning the cellular aspects of ACI is still limited, the aim of the present study was to investigate relevant differences...... between chondrocyte quality after in vitro cultivation and possible correlations with patient-specific factors. DESIGN: Cell quality of 252 consecutive ACI patients was assessed after chondrocyte in vitro expansion by determination of the expression of cartilage relevant surface marker CD44 and cartilage......, aggrecan or collagen type II nor cell density or viability after proliferation seemed to correlate with the grade of joint degeneration, defect aetiology or patient gender. However, chondrocytes harvested from the knee joints of patients at less than 20 years of age showed significantly higher expression...

Overexpression of Galnt3 in chondrocytes resulted in dwarfism due to the increase of mucin-type O-glycans and reduction of glycosaminoglycans.

Science.gov (United States)

Yoshida, Carolina Andrea; Kawane, Tetsuya; Moriishi, Takeshi; Purushothaman, Anurag; Miyazaki, Toshihiro; Komori, Hisato; Mori, Masako; Qin, Xin; Hashimoto, Ayako; Sugahara, Kazuyuki; Yamana, Kei; Takada, Kenji; Komori, Toshihisa

2014-09-19

Galnt3, UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 3, transfers N-acetyl-D-galactosamine to serine and threonine residues, initiating mucin type O-glycosylation of proteins. We searched the target genes of Runx2, which is an essential transcription factor for chondrocyte maturation, in chondrocytes and found that Galnt3 expression was up-regulated by Runx2 and severely reduced in Runx2(-/-) cartilaginous skeletons. To investigate the function of Galnt3 in chondrocytes, we generated Galnt3(-/-) mice and chondrocyte-specific Galnt3 transgenic mice under the control of the Col2a1 promoter-enhancer. Galnt3(-/-) mice showed a delay in endochondral ossification and shortened limbs at embryonic day 16.5, suggesting that Galnt3 is involved in chondrocyte maturation. Galnt3 transgenic mice presented dwarfism, the chondrocyte maturation was retarded, the cell cycle in chondrocytes was accelerated, premature chondrocyte apoptosis occurred, and the growth plates were disorganized. The binding of Vicia villosa agglutinin, which recognizes the Tn antigen (GalNAc-O-Ser/Thr), was drastically increased in chondrocytes, and aggrecan (Acan) was highly enriched with Tn antigen. However, safranin O staining, which recognizes glycosaminoglycans (GAGs), and Acan were severely reduced. Chondroitin sulfate was reduced in amount, but the elongation of chondroitin sulfate chains had not been severely disturbed in the isolated GAGs. These findings indicate that overexpression of Galnt3 in chondrocytes caused dwarfism due to the increase of mucin-type O-glycans and the reduction of GAGs, probably through competition with xylosyltransferases, which initiate GAG chains by attaching O-linked xylose to serine residues, suggesting a negative effect of Galnt family proteins on Acan deposition in addition to the positive effect of Galnt3 on chondrocyte maturation. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Down-regulation of ATF2 in the inhibition of T-2-toxin-induced chondrocyte apoptosis by selenium chondroitin sulfate nanoparticles

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Han, Jing; Guo, Xiong

2013-12-01

Selenium chondroitin sulfate nanoparticles (SeCS) with a size range of 30-200 nm were obtained in our previous study. Meanwhile, the up-regulated expression of ATF2 mRNA and protein levels could be observed in the cartilage from Kashin-Beck disease (KBD) patients. In this paper, we investigated the inhibition effect of SeCS on T-2-toxin-induced apoptosis of chondrocyte from KBD patients. Here, we found that when the chondrocytes were treated with T-2 toxin, the chondrocyte apoptosis performed in a concentration-dependent manner. The apoptosis of chondrocyte induced by T-2 toxin involved the increased levels of ATF2, JNK and p38 mRNAs and related protein expression. SeCS could partly block the T-2-toxin-induced chondrocyte apoptosis by decreasing the expression of ATF2, JNK and p38 mRNAs and p-JNK, p-38, ATF2 and p-ATF2 proteins. JNK and p38 pathways involved in the apoptosis of chondrocyte induced by T-2 toxin, and SeCS was efficient in the inhibition of chondrocyte apoptosis by T-2 toxin. These results suggested that SeCS had a potential for further prevention and treatment for KBD as well as other selenium deficiency disease.

Surface modification of cyclic olefin copolymers for osteochondral defect repair can increase pro-destructive potential of human chondrocytes in vitro

Czech Academy of Sciences Publication Activity Database

Polanská, M.; Hulejová, H.; Petrtýl, M.; Bastl, Zdeněk; Spirovová, Ilona; Kruliš, Zdeněk; Horák, Zdeněk; Veigl, D.; Šenolt, L.

2010-01-01

Roč. 59, č. 2 (2010), s. 247-253 ISSN 0862-8408 R&D Projects: GA ČR GA106/06/0761 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40500505 Keywords : osteochondral defects * cycloolefin copolymer * chondrocytes * biocompatibility Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.646, year: 2010

The influence of “Efial” medicine on the chondrocytes functional state

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N. А. Volkova

2014-12-01

Full Text Available Renewal of articular cartilage is a topical issue of modern orthopedics. High frequency of injuries, complexity of clinical diagnosis and subsequent treatment, and also the delay in recovery lead to the development of osteoarthritis, and in some cases, to disability. Articular cartilage belongs to the highly specialized tissues, which is characterized by the lack of blood supply, the low number of cell elements that are placed in the matrix, include collagen, proteoglycans, non-collagenous proteins and water. For the treatment of articular cartilage lesions the medicine which are tissue specific promoters of regeneration are used. The ability of most reparants to stimulate cartilage regeneration combines with other effects, such as: anti-inflammatory, antioxidant and antibacterial. The purpose of administration of these medicines is to stimulate regeneration of tissue in the area of injury. The aim of research was to investigate the effect of “Efial” medicine on functional state of chondrocytes in cultivation conditions. Materials and methods. The chondrocytes were obtained from articular cartilage of rats by enzymatic disaggregation. In all experiments the seeding concentration of chondrocytes was 1.2 x 104 cells/cm2.The "Efial" medicine in concentration of peptides of 0.137 mg/ml was used. Investigated concentration range was 70; 7.6; 1.5; 0.15µg/ml and 75; 15; 1.5 ng/ml. The medicine was added to the cell culture medium when seeding and on the 3rd cultivation day. The control (comparison group was the cultures of chondrocytes which were cultivated under the same conditions without medicine addition. Functional state of chondrocytes under interaction with investigated "Efial" medicine was evaluated by the presence of glycosaminoglycans after Toluidine blue staining (Fluka, Germany and collagen type II (1:200 and FITC-conjugate, Sigma -Aldrich, USA. For statistical study ANOVA and t-Student tests were used with application of Microsoft

Hydrostatic Pressure Influences HIF-2 Alpha Expression in Chondrocytes

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Hiroaki Inoue

2015-01-01

Full Text Available Hypoxia-inducible factor (HIF-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP 70, HIF-2α, nuclear factor kappa B (NF-κB, matrix metalloproteinase (MMP-13, MMP-3, and vascular endothelial growth factor (VEGF gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α.

Hydrostatic pressure influences HIF-2 alpha expression in chondrocytes.

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Inoue, Hiroaki; Arai, Yuji; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Tsuchida, Shinji; Matsuki, Tomohiro; Ueshima, Keiichirou; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

2015-01-05

Hypoxia-inducible factor (HIF)-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP) 70, HIF-2α, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-13, MMP-3, and vascular endothelial growth factor (VEGF) gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α.

Experimental study of tissue-engineered cartilage allograft with RNAi chondrocytes in vivo

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Wang ZH

2014-05-01

Full Text Available Zhenghui Wang,1 Xiaoli Li,2 Xi-Jing He,3 Xianghong Zhang,1 Zhuangqun Yang,4 Min Xu,1 Baojun Wu,1 Junbo Tu,5 Huanan Luo,1 Jing Yan11Department of Otolaryngology – Head and Neck Surgery, 2Department of Dermatology, 3Department of Orthopedics, The Second Hospital, Xi’an Jiaotong University, 4Department of Plastic and Burns Surgery, The First Hospital, Xi’an Jiaotong University, 5Department of Oral and Maxillofacial Plastic Surgery, The Stomatological Hospital, Xi’an Jiaotong University, Xi’an, People’s Republic of ChinaPurpose: To determine the effects of RNA interference (RNAi on chondrocyte proliferation, function, and immunological rejection after allogenic tissue-engineered cartilage transplantation within bone matrix gelatin scaffolds.Methods: Seven million rat normal and RNAi chondrocytes were harvested and separately composited with fibrin glue to make the cell suspension, and then transplanted subcutaneously into the back of Sprague Dawley rats after being cultured for 10 days in vitro. Untransplanted animals served as the control group. The allograft and immunological response were examined at 1, 2, 4, 8, and 12 months postoperatively with hematoxylin and eosin histochemical staining, immunohistochemical staining (aggrecan, type II collagen, class I and II major histocompatibility complex, and flow cytometry for peripheral blood cluster of differentiation 4+ (CD4+ and CD8+ T-cells.Results: There was no infection or death in the rats except one, which died in the first week. Compared to the control group, the RNAi group had fewer eukomonocytes infiltrated, which were only distributed around the graft. The ratio of CD4+/CD8+ T-cells in the RNAi group was significantly lower than the normal one (P<0.05. There were many more positively stained chondrocytes and positively stained areas around the cells in the RNAi group, which were not found in the control group.Conclusion: The aggrecanase-1 and aggrecanase-2 RNAi for chondrocytes

MR imaging of autologous chondrocyte implantation of the knee

Energy Technology Data Exchange (ETDEWEB)

James, S.L.J.; Connell, D.A.; Saifuddin, A.; Skinner, J.A.; Briggs, T.W.R. [RNOH Stanmore, Department of Radiology, Stanmore, Middlesex (United Kingdom)

2006-05-15

Autologous chondrocyte implantation (ACI) is a surgical technique that is increasingly being used in the treatment of full-thickness defects of articular cartilage in the knee. It involves the arthroscopic harvesting and in vitro culture of chondrocytes that are subsequently implanted into a previously identified chondral defect. The aim is to produce a repair tissue that closely resembles hyaline articular cartilage that gradually becomes incorporated, restoring joint congruity. Over the long term, it is hoped that this will prevent the progression of full-thickness articular cartilage defects to osteoarthritis. This article reviews the indications and operative procedure performed in ACI. Magnetic resonance imaging (MRI) sequences that provide optimal visualization of articular cartilage in the post-operative period are discussed. Normal appearances of ACI on MRI are presented along with common complications that are encountered with this technique. (orig.)

IFT88 influences chondrocyte actin organization and biomechanics.

Science.gov (United States)

Wang, Z; Wann, A K T; Thompson, C L; Hassen, A; Wang, W; Knight, M M

2016-03-01

Primary cilia are microtubule based organelles which control a variety of signalling pathways important in cartilage development, health and disease. This study examines the role of the intraflagellar transport (IFT) protein, IFT88, in regulating fundamental actin organisation and mechanics in articular chondrocytes. The study used an established chondrocyte cell line with and without hypomorphic mutation of IFT88 (IFT88(orpk)). Confocal microscopy was used to quantify F-actin and myosin IIB organisation. Viscoelastic cell and actin cortex mechanics were determined using micropipette aspiration with actin dynamics visualised in live cells transfected with LifeACT-GFP. IFT88(orpk) cells exhibited a significant increase in acto-myosin stress fibre organisation relative to wild-type (WT) cells in monolayer and an altered response to cytochalasin D. Rounded IFT88(orpk) cells cultured in suspension exhibited reduced cortical actin expression with reduced cellular equilibrium modulus. Micropipette aspiration resulted in reduced membrane bleb formation in IFT88(orpk) cells. Following membrane blebbing, IFT88(orpk) cells exhibited slower reformation of the actin cortex. IFT88(orpk) cells showed increased actin deformability and reduced cortical tension confirming that IFT regulates actin cortex mechanics. The reduced cortical tension is also consistent with the reduced bleb formation. This study demonstrates for the first time that the ciliary protein IFT88 regulates fundamental actin organisation and the stiffness of the actin cortex leading to alterations in cell deformation, mechanical properties and blebbing in an IFT88 chondrocyte cell line. This adds to the growing understanding of the role of primary cilia and IFT in regulating cartilage biology. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

The effect of dexamethasone and triiodothyronine on terminal differentiation of primary bovine chondrocytes and chondrogenically differentiated mesenchymal stem cells.

Science.gov (United States)

Randau, Thomas M; Schildberg, Frank A; Alini, Mauro; Wimmer, Matthias D; Haddouti, El-Mustapha; Gravius, Sascha; Ito, Keita; Stoddart, Martin J

2013-01-01

The newly evolved field of regenerative medicine is offering solutions in the treatment of bone or cartilage loss and deficiency. Mesenchymal stem cells, as well as articular chondrocytes, are potential cells for the generation of bone or cartilage. The natural mechanism of bone formation is that of endochondral ossification, regulated, among other factors, through the hormones dexamethasone and triiodothyronine. We investigated the effects of these hormones on articular chondrocytes and chondrogenically differentiated mesenchymal stem cells, hypothesizing that these hormones would induce terminal differentiation, with chondrocytes and differentiated stem cells being similar in their response. Using a 3D-alginate cell culture model, bovine chondrocytes and chondrogenically differentiated stem cells were cultured in presence of triiodothyronine or dexamethasone, and cell proliferation and extracellular matrix production were investigated. Collagen mRNA expression was measured by real-time PCR. Col X mRNA and alkaline phosphatase were monitored as markers of terminal differentiation, a prerequisite of endochondral ossification. The alginate culture system worked well, both for the culture of chondrocytes and for the chondrogenic differentiation of mesenchymal stem cells. Dexamethasone led to an increase in glycosaminoglycan production. Triiodothyronine increased the total collagen production only in chondrocytes, where it also induced signs of terminal differentiation, increasing both collagen X mRNA and alkaline phosphatase activity. Dexamethasone induced terminal differentiation in the differentiated stem cells. The immature articular chondrocytes used in this study seem to be able to undergo terminal differentiation, pointing to their possible role in the onset of degenerative osteoarthritis, as well as their potential for a cell source in bone tissue engineering. When chondrocyte-like cells, after their differentiation, can indeed be moved on towards terminal

Improvement of the Chondrocyte-Specific Phenotype upon Equine Bone Marrow Mesenchymal Stem Cell Differentiation: Influence of Culture Time, Transforming Growth Factors and Type I Collagen siRNAs on the Differentiation Index

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Thomas Branly

2018-02-01

Full Text Available Articular cartilage is a tissue characterized by its poor intrinsic capacity for self-repair. This tissue is frequently altered upon trauma or in osteoarthritis (OA, a degenerative disease that is currently incurable. Similar musculoskeletal disorders also affect horses and OA incurs considerable economic loss for the equine sector. In the view to develop new therapies for humans and horses, significant progress in tissue engineering has led to the emergence of new generations of cartilage therapy. Matrix-associated autologous chondrocyte implantation is an advanced 3D cell-based therapy that holds promise for cartilage repair. This study aims to improve the autologous chondrocyte implantation technique by using equine mesenchymal stem cells (MSCs from bone marrow differentiated into chondrocytes that can be implanted in the chondral lesion. The optimized protocol relies on culture under hypoxia within type I/III collagen sponges. Here, we explored three parameters that influence MSC differentiation: culture times, growth factors and RNA interference strategies. Our results suggest first that an increase in culture time from 14 to 28 or 42 days lead to a sharp increase in the expression of chondrocyte markers, notably type II collagen (especially the IIB isoform, along with a concomitant decrease in HtrA1 expression. Nevertheless, the expression of type I collagen also increased with longer culture times. Second, regarding the growth factor cocktail, TGF-β3 alone showed promising result but the previously tested association of BMP-2 and TGF-β1 better limits the expression of type I collagen. Third, RNA interference targeting Col1a2 as well as Col1a1 mRNA led to a more significant knockdown, compared with a conventional strategy targeting Col1a1 alone. This chondrogenic differentiation strategy showed a strong increase in the Col2a1:Col1a1 mRNA ratio in the chondrocytes derived from equine bone marrow MSCs, this ratio being considered as an

Improvement of the Chondrocyte-Specific Phenotype upon Equine Bone Marrow Mesenchymal Stem Cell Differentiation: Influence of Culture Time, Transforming Growth Factors and Type I Collagen siRNAs on the Differentiation Index.

Science.gov (United States)

Branly, Thomas; Contentin, Romain; Desancé, Mélanie; Jacquel, Thibaud; Bertoni, Lélia; Jacquet, Sandrine; Mallein-Gerin, Frédéric; Denoix, Jean-Marie; Audigié, Fabrice; Demoor, Magali; Galéra, Philippe

2018-02-01

Articular cartilage is a tissue characterized by its poor intrinsic capacity for self-repair. This tissue is frequently altered upon trauma or in osteoarthritis (OA), a degenerative disease that is currently incurable. Similar musculoskeletal disorders also affect horses and OA incurs considerable economic loss for the equine sector. In the view to develop new therapies for humans and horses, significant progress in tissue engineering has led to the emergence of new generations of cartilage therapy. Matrix-associated autologous chondrocyte implantation is an advanced 3D cell-based therapy that holds promise for cartilage repair. This study aims to improve the autologous chondrocyte implantation technique by using equine mesenchymal stem cells (MSCs) from bone marrow differentiated into chondrocytes that can be implanted in the chondral lesion. The optimized protocol relies on culture under hypoxia within type I/III collagen sponges. Here, we explored three parameters that influence MSC differentiation: culture times, growth factors and RNA interference strategies. Our results suggest first that an increase in culture time from 14 to 28 or 42 days lead to a sharp increase in the expression of chondrocyte markers, notably type II collagen (especially the IIB isoform), along with a concomitant decrease in HtrA1 expression. Nevertheless, the expression of type I collagen also increased with longer culture times. Second, regarding the growth factor cocktail, TGF-β3 alone showed promising result but the previously tested association of BMP-2 and TGF-β1 better limits the expression of type I collagen. Third, RNA interference targeting Col1a2 as well as Col1a1 mRNA led to a more significant knockdown, compared with a conventional strategy targeting Col1a1 alone. This chondrogenic differentiation strategy showed a strong increase in the Col2a1 : Col1a1 mRNA ratio in the chondrocytes derived from equine bone marrow MSCs, this ratio being considered as an index of the

Subchondral Bone Plate Thickening Precedes Chondrocyte Apoptosis and Cartilage Degradation in Spontaneous Animal Models of Osteoarthritis

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Zaitunnatakhin Zamli

2014-01-01

Full Text Available Osteoarthritis (OA is the most common joint disorder characterised by bone remodelling and cartilage degradation and associated with chondrocyte apoptosis. These processes were investigated at 10, 16, 24, and 30 weeks in Dunkin Hartley (DH and Bristol Strain 2 (BS2 guinea pigs that develop OA spontaneously. Both strains had a more pronounced chondrocyte apoptosis, cartilage degradation, and subchondral bone changes in the medial than the lateral side of the tibia, and between strains, the changes were always greater and faster in DH than BS2. In the medial side, a significant increase of chondrocyte apoptosis and cartilage degradation was observed in DH between 24 and 30 weeks of age preceded by a progressive thickening and stiffening of subchondral bone plate (Sbp. The Sbp thickness consistently increased over the 30-week study period but the bone mineral density (BMD of the Sbp gradually decreased after 16 weeks. The absence of these changes in the medial side of BS2 may indicate that the Sbp of DH was undergoing remodelling. Chondrocyte apoptosis was largely confined to the deep zone of articular cartilage and correlated with thickness of the subchondral bone plate suggesting that cartilage degradation and chondrocyte apoptosis may be a consequence of continuous bone remodelling during the development of OA in these animal models of OA.

Electrospun gelatin/polycaprolactone nanofibrous membranes combined with a coculture of bone marrow stromal cells and chondrocytes for cartilage engineering

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He X

2015-03-01

Full Text Available Xiaomin He,1,* Bei Feng,1,2,* Chuanpei Huang,1 Hao Wang,1 Yang Ge,1 Renjie Hu,1 Meng Yin,1 Zhiwei Xu,1 Wei Wang,1 Wei Fu,1,2 Jinghao Zheng1 1Department of Pediatric Cardiothoracic Surgery, 2Institute of Pediatric Translational Medicine, Shanghai Children’s Medical Center School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Electrospinning has recently received considerable attention, showing notable potential as a novel method of scaffold fabrication for cartilage engineering. The aim of this study was to use a coculture strategy of chondrocytes combined with electrospun gelatin/polycaprolactone (GT/PCL membranes, instead of pure chondrocytes, to evaluate the formation of cartilaginous tissue. We prepared the GT/PCL membranes, seeded bone marrow stromal cell (BMSC/chondrocyte cocultures (75% BMSCs and 25% chondrocytes in a sandwich model in vitro, and then implanted the constructs subcutaneously into nude mice for 12 weeks. Gross observation, histological and immunohistological evaluation, glycosaminoglycan analyses, Young’s modulus measurement, and immunofluorescence staining were performed postimplantation. We found that the coculture group formed mature cartilage-like tissue, with no statistically significant difference from the chondrocyte group, and labeled BMSCs could differentiate into chondrocyte-like cells under the chondrogenic niche of chondrocytes. This entire strategy indicates that GT/PCL membranes are also a suitable scaffold for stem cell-based cartilage engineering and may provide a potentially clinically feasible approach for cartilage repairs. Keywords: electrospinning, nanocomposite, cartilage tissue engineering, nanomaterials, stem cells

Influence of bone morphogenetic protein-2 on the extracellular matrix, material properties, and gene expression of long-term articular chondrocyte cultures: loss of chondrocyte stability.

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Krawczak, David A; Westendorf, Jennifer J; Carlson, Cathy S; Lewis, Jack L

2009-06-01

The aim of this study was to determine the effects of bone morphogenetic protein-2 (BMP-2) on articular chondrocyte tissues grown as monolayers in vitro for up to 8 weeks. Articular chondrocytes were isolated from New Zealand White rabbits and plated in monolayer cultures. The cultures were supplemented with 100 ng/mL of BMP-2 for up to 8 weeks and the extracellular matrix (ECM) composition, material properties, and messenger RNA (mRNA) expression were analyzed. mRNA expression of cartilage-specific genes, type II collagen, and aggrecan showed that BMP-2 enhanced chondrocyte stability for up to 3 weeks. After 3 weeks in culture, there was substantially more type I collagen expression and more osteopontin and runt-related transcription factor 2 expression in 5- and 8-week cultures treated with BMP-2 than in controls. Additionally, matrix metalloproteinase-13 and ADAMTS-5 (A disintegrin-like and metalloproteinase with thrombospondin 5) were upregulated in 5- and 8-week cultures treated with BMP-2, coinciding with a loss of ECM density, collagen, and proteoglycan. Eight-week tissue stimulated with BMP-2 was more fragile and tore more easily when removed from the culture dish as compared to controls, suggesting temporal limitations to the effectiveness of BMP-2 in monolayer systems and perhaps other models to enhance the generation of a cartilage-like tissue for tissue engineering purposes.

Regulation of α5 and αV Integrin Expression by GDF-5 and BMP-7 in Chondrocyte Differentiation and Osteoarthritis.

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David Garciadiego-Cázares

Full Text Available The Integrin β1 family is the major receptors of the Extracellular matrix (ECM, and the synthesis and degradation balance of ECM is seriously disrupted during Osteoarthritis (OA. In this scenario, integrins modify their pattern expression and regulate chondrocyte differentiation in the articular cartilage. Members of the Transforming growth factor beta (Tgf-β Superfamily, such as Growth differentiation factor 5 (Gdf-5 and Bone morphogenetic protein 7 (Bmp-7, play a key role in joint formation and could regulate the integrin expression during chondrocyte differentiation and osteoarthritis progression in an experimental OA rat model. Decrease of α5 integrin expression in articular cartilage was related with chondrocyte dedifferentiation during OA progression, while increase of α1, α2, and α3 integrin expression was related with fibrous areas in articular cartilage during OA. Hypertrophic chondrocytes expressed αV integrin and was increased in the articular cartilage of rats with OA. Integrin expression during chondrocyte differentiation was also analyzed in a micromass culture system of mouse embryo mesenchymal cells, micromass cultures was treated with Gdf-5 or Bmp-7 for 4 and 6 days, respectively. Gdf-5 induced the expression of the α5 sub-unit, while Bmp-7 induced the expression of the αV sub-unit. This suggests a switch in signaling for prehypertrophic chondrocyte differentiation towards hypertrophy, where Gdf-5 could maintain the articular chondrocyte phenotype and Bmp-7 would induce hypertrophy. Decrease of Ihh expression during late stages of OA in rat model suggest that the ossification in OA rat knees and endochondral ossification could be activated by Bmp-7 and αV integrin in absence of Ihh. Thus, chondrocyte phenotype in articular cartilage is similar to prehypetrophic chondrocyte in growth plate, and is preserved due to the presence of Indian hedgehog (Ihh, Gdf-5 and α5 integrin to maintain articular cartilage and prevent

Kaempferol Alleviates the Interleukin-1β-Induced Inflammation in Rat Osteoarthritis Chondrocytes via Suppression of NF-κB.

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Zhuang, Zhengling; Ye, Guangqun; Huang, Bin

2017-08-14

BACKGROUND This study was designed to examine the anti-inflammatory and anti-osteoarthritis (OA) effects of kaempferol in rat articular chondrocytes stimulated with interleukin-1β. MATERIAL AND METHODS Rat articular chondrocytes cultures were treated with interleukin-1β alone or with kaempferol (25, 50, 100, and 200 μM) and interleukin-1β. The effect of kaempferol on chondrocyte cells viability was measured by MTT assay. The effect on prostaglandin E2 (PGE2) and nitric oxide (NO) level were also assessed using the ELISA and Griess reagent, respectively, for kaempferol activity. Moreover, the expression of iNOS, Cox-2 and activation of NF-κB under influence of kaempferol was also assessed by Western blot. RESULTS Kaempferol treatment (up to 100 μM) in a concentration-dependent way caused reduction in the interleukin-1b-stimulated formations of PGE2 and NO. Kaempferol also upregulated the expression of iNOS and Cox-2 in interleukin-1β-stimulated rat OA chondrocytes. Additionally, kaempferol was found to inhibit the IkBa degradation and NF-κB activation in rat chondrocytes stimulated with interleukin-1β. CONCLUSIONS Kaempferol significantly caused reduction in interleukin-1β-stimulated pro-inflammatory mediators in rat OA chondrocytes by inhibiting the NF-κB pathway. These results suggest that kaempferol had significant anti-inflammatory and anti-arthritis effects. Thus, kaempferol, as a novel therapeutic active agent, may prevent, stop, or retard the progression of OA.

MicroRNA-195 induced apoptosis in hypoxic chondrocytes by targeting hypoxia-inducible factor 1 alpha.

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Bai, R; Zhao, A-Q; Zhao, Z-Q; Liu, W-L; Jian, D-M

2015-02-01

The chondrocytes, the resident cells of cartilage, are maintained and take effects in the whole life upon chronic hypoxic exposure, which hypoxia-inducible factor 1 alpha (HIF-1α) play pivotal roles in response to. Dysregulation of some microRNA (miRNAs) have also been identified to be involved in hypoxia-related physiologic and pathophysiologic responses in some tissues or cell lines. However, the mechanism of miRNAs reponse to hypoxia remain largely unknown in chondrocytes, including the microRNA-195 (miR-195). AIM To investigate the effects of microRNAs (miRNAs) and hypoxia-inducible factor 1 alpha (HIF-1α) on chondrocytes in physiologic environment. We compared the expression of miR-195 and HIF-1α mRNA on hypoxia with that on normoxia in ATDC 5 cells by qRT-PCR. Further experiments was performed to confirmed the relationships of miR-195 and HIF-1α by bioinformatics analysis and dual reporter gene assay. we also assessed the effect of miR-195 on apoptosis in hypoxic ATDC 5 cells by transfect with miR-195 mimics. It was found the downregulated miR-195 and upregulated HIF-1α were present in hypoxic ATDC 5 cells. miR-195 negatively regulated HIF-1α by targeting its 3'-untranslated region. Moreover, the founding indicated miR-195 greatly increased apoptosis and downregulated HIF-1α mRNA occurred simultaneously in hypoxic chondrocytes. We concluded that miR-195 induced apoptosis in hypoxic chondrocytes by directly targeting HIF-1α.

Is the repair of articular cartilage lesion by costal chondrocyte transplantation donor age-dependent? An experimental study in rabbits.

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Janusz Popko

2006-09-01

Full Text Available The repair of chondral injuries is a very important problem and a subject of many experimental and clinical studies. Different techniques to induce articular cartilage repair are under investigation. In the present study, we have investigated whether the repair of articular cartilage folowing costal chondrocyte transplantation is donor age-dependent. Transplantation of costal chondrocytes from 4- and 24-week old donors, with artificially induced femoral cartilage lesion, was performed on fourteen 20-week-old New Zealand White male rabbits. In the control group, the lesion was left without chondrocyte transplantation. The evaluation of the cartilage repair was performed after 12 weeks of transplantation. We analyzed the macroscopic and histological appearance of the newly formed tissue. Immunohistochemistry was also performed using monoclonal antibodies against rabbit collagen type II. The newly formed tissue had a hyaline-like appearance in most of the lesions after chondrocyte transplantation. Positive immunohistochemical reaction for collagen II was also observed in both groups with transplanted chondrocytes. Cartilage from adult donors required longer isolation time and induced slightly poorer repair. However, hyaline-like cartilage was observed in most specimens from this group, in contrast to the control group, where fibrous connective tissue filled the lesions. Rabbit costal chondrocytes seem to be a potentially useful material for inducing articular cartilage repair and, even more important, they can also be derived from adult, sexually mature animals.

Andrographolide Enhances Proliferation and Prevents Dedifferentiation of Rabbit Articular Chondrocytes: An In Vitro Study

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Li-ke Luo

2015-01-01

Full Text Available As the main active constituent of Andrographis paniculata that was applied in treatment of many diseases including inflammation in ancient China, andrographolide (ANDRO was found to facilitate reduction of edema and analgesia in arthritis. This suggested that ANDRO may be promising anti-inflammatory agent to relieve destruction and degeneration of cartilage after inflammation. In this study, the effect of ANDRO on rabbit articular chondrocytes in vitro was investigated. Results showed that not more than 8 μM ANDRO did no harm to chondrocytes (P0.05. The viability assay, hematoxylin-eosin, safranin O, and immunohistochemical staining also showed better performances in ANDRO groups. As to the doses, 3 μM ANDRO showed the best performance. The results indicate that ANDRO can accelerate proliferation of rabbit articular chondrocytes in vitro and meanwhile maintain the phenotype, which may provide valuable references for further exploration on arthritis.

99mTc-labeled chondroitin sulfate-uptake by chondrocytes and cartilage. Potential agent for osteoarthritis imaging?

International Nuclear Information System (INIS)

Sobal, G.; Sinzinger, H.; Menzel, J.

2002-01-01

Aim: Chondroitin sulfate (CS) is an endogenous component of cartilage proteoglycan which could monitor osteoarthritic cartilage degradation after radiolabeling. This substance is used in the treatment of human osteoarthritis as a slow acting symptomatic drug (CONDROSULF; Sanova Pharma, Vienna; Ibsa, Switzerland). Material and Methods: Radiolabeling of CS was performed using 99m TcO 4 -/stannous chloride in 0.50 M sodium acetate buffer at pH 5.0. The quality control of the tracer was performed using ITLC-SG chromatography and 0.2 M saline in 10% ethanol as solvent to detect colloid content. Aluminium oxide IB-F TLC-sheets and ethanol as solvent were used to estimate free pertechnetate. For uptake studies cultured human chondrocytes and age-matched cartilage were used. Uptake of the tracer in chondrocytes was studied in monolayer and in suspension cultures at 37 0 C. Uptake was monitored for a total of 120-180 minutes, samples being drawn every 10 minutes. Because the commercially available drug Condrosulf contains calcium stearate as additive to improve the resorption of the drug, we investigated also the uptake with and without additive. Results: The tracer was stable over 6h period after labeling (95% of the radiochemical purity). In plasma the stability was lower amounting to 75%. Viability of chondrocytes after incubation with either CS-preparation was found by trypan blue exclusion to be above 95 %. Uptake of the tracer performed in monolayer ± additives was low and amounted to 0.5%±0.05%, n=6. The cells were saturated already after an incubation interval of 10 minutes. In suspension cultures a maximal uptake of 1.0%±0.1%, n=6 and 5.9%±0.65%, n=6 was found, without and with additives, respectively, the saturation was achieved after 100 min. Thus, not only the resorption of the drug is enhanced by Ca-stearate, but also uptake increases in presence of this additive. Using human rib cartilage the uptake of the tracer was much higher amounting to 4.9%±2.3%, n

Overexpression of hsa-miR-148a promotes cartilage production and inhibits cartilage degradation by osteoarthritic chondrocytes

NARCIS (Netherlands)

Vonk, L A; Kragten, A H M; Dhert, W J A; Saris, D B F; Creemers, L B

OBJECTIVE: Hsa-miR-148a expression is decreased in Osteoarthritis (OA) cartilage, but its functional role in cartilage has never been studied. Therefore, our aim was to investigate the effects of overexpressing hsa-miR-148a on cartilage metabolism of OA chondrocytes. DESIGN: OA chondrocytes were

Phosphodiesterase isoenzyme families in human osteoarthritis chondrocytes – functional importance of phosphodiesterase 4

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Tenor, Hermann; Hedbom, Erik; Häuselmann, Hans-Jörg; Schudt, Christian; Hatzelmann, Armin

2002-01-01

We studied whether selective inhibitors of cyclic nucleotide hydrolysing phosphodiesterase (PDE) isoenzymes influence IL-1β-induced nitric oxide (NO) release from human articular chondrocytes. In addition, the pattern of PDE isoenzymes contributing to cyclic nucleotide hydrolysis in human chondrocytes was characterized.Chondrocytes were isolated from human osteoarthritic cartilage and cultured in alginate beads. IL-1β-induced chondrocyte products (nitric oxide and prostaglandin E2) were measured in culture supernatants after 48 h incubation time. PDE activities were assessed in chondrocyte lysates. Inducible nitric oxide synthase (iNOS) and PDE4A-D proteins were detected by immunoblotting.The selective PDE4 inhibitors Piclamilast and Roflumilast partially attenuated IL-1β-induced NO production whereas selective inhibitors of PDE2 (EHNA), PDE3 (Motapizone) or PDE5 (Sildenafil) were inactive. Indomethacin reversed the reduction of IL-1β-induced NO by PDE4 inhibitors. It was shown that autocrine prostaglandin E2 (PGE2) enabled PDE4 inhibitors to reduce IL-1β-induced NO in this experimental setting.Major PDE4 and PDE1 activities were identified in chondrocyte lysates whereas only minor activities of PDE2, 3 and 5 were found. IL-1β and cyclic AMP-mimetics upregulated PDE4 activity and this was associated with an augmentation of PDE4B2 protein.Based on the view that nitric oxide contributes to cartilage degradation in osteoarthritis our study suggests that PDE4 inhibitors may have chondroprotective effects. PMID:11834608

Human platelet lysate successfully promotes proliferation and subsequent chondrogenic differentiation of adipose-derived stem cells: a comparison with articular chondrocytes.

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Hildner, F; Eder, M J; Hofer, K; Aberl, J; Redl, H; van Griensven, M; Gabriel, C; Peterbauer-Scherb, A

2015-07-01

Fetal calf serum (FCS) bears a potential risk for carrying diseases and eliciting immune reactions. Nevertheless, it still represents the gold standard as medium supplement in cell culture. In the present study, human platelet lysate (PL) was tested as an alternative to FCS for the expansion and subsequent chondrogenic differentiation of human adipose-derived stem cells (ASCs). ASCs were expanded with 10% FCS (group F) or 5% PL (group P). Subsequently, three-dimensional (3D) micromass pellets were created and cultured for 5 weeks in chondrogenic differentiation medium. Additionally, the de- and redifferentiation potential of human articular chondrocytes (HACs) was evaluated and compared to ASCs. Both HACs and ASCs cultured with PL showed strongly enhanced proliferation rates. Redifferentiation of HACs was possible for cells expanded up to 3.3 population doublings (PD). At this stage, PL-expanded HACs demonstrated better redifferentiation potential than FCS-expanded cells. ASCs could also be differentiated following extended passaging. Glycosaminoglycan (GAG) quantification and qRT-PCR of 10 cartilage related markers demonstrated a tendency for increased chondrogenic differentiation of PL-expanded ASCs compared to cells expanded with FCS. Histologically, collagen type II but also collagen type X was mainly present in group P. The present study demonstrates that PL strongly induces proliferation of ASCs, while the chondrogenic differentiation potential is retained. HACs also showed enhanced proliferation and even better redifferentiation when previously expanded with PL. This suggests that PL is superior to FCS as a supplement for the expansion of ASCs and HACs, particularly with regard to chondrogenic (re)differentiation. Copyright © 2013 John Wiley & Sons, Ltd.

Overexpression of hsa-miR-148a promotes cartilage production and inhibits cartilage degradation by osteoarthritic chondrocytes

NARCIS (Netherlands)

Vonk, Lucienne A.; Kragten, Angela H.M.; Dhert, Wouter J.; Saris, Daniël B.F.; Creemers, Laura B.

2014-01-01

Objective Hsa-miR-148a expression is decreased in OA cartilage, but its functional role in cartilage has never been studied. Therefore, our aim was to investigate the effects of overexpressing hsa-miR-148a on cartilage metabolism of OA chondrocytes. Design OA chondrocytes were transfected with a

Induction of increased cAMP levels in articular chondrocytes blocks matrix metalloproteinase-mediated cartilage degradation, but not aggrecanase-mediated cartilage degradation

DEFF Research Database (Denmark)

Karsdal, Morten Asser; Sumer, Eren Ufuk; Wulf, Helle

2007-01-01

OBJECTIVE: Calcitonin has been suggested to have chondroprotective effects. One signaling pathway of calcitonin is via the second messenger cAMP. We undertook this study to investigate whether increased cAMP levels in chondrocytes would be chondroprotective. METHODS: Cartilage degradation......-dependently inhibited by forskolin and IBMX. The highest concentration of IBMX lowered cytokine-induced release of sGAG by 72%. CONCLUSION: Levels of cAMP in chondrocytes play a key role in controlling catabolic activity. Increased cAMP levels in chondrocytes inhibited MMP expression and activity and consequently...... strongly inhibited cartilage degradation. Specific cAMP modulators in chondrocytes may be potential treatments for cartilage degenerative diseases....

The major basement membrane components localize to the chondrocyte pericellular matrix--a cartilage basement membrane equivalent?

DEFF Research Database (Denmark)

Kvist, Alexander J.; Nyström, Alexander; Hultenby, Kjell

2007-01-01

In this study, we demonstrate that articular cartilage chondrocytes are surrounded by the defining basement membrane proteins laminin, collagen type IV, nidogen and perlecan, and suggest that these form the functional equivalent of a basement membrane. We found by real-time PCR that mouse...... chondrocytes express these four cardinal components of basement membranes and demonstrated by immunohistochemistry that the proteins are present in bovine and mouse cartilage tissues and are deposited in a thin pericellular structure. Immunoelectron microscopy confirmed high laminin concentration...... becomes less distinct, especially in areas of obvious mechanical attrition. Interestingly, individual laminin subunits were located in different zones of the cartilage, with laminin alpha1 showing preferential localization around a select population of superficial layer chondrocytes. We propose...

Noonan syndrome-causing SHP2 mutants impair ERK-dependent chondrocyte differentiation during endochondral bone growth.

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Tajan, Mylène; Pernin-Grandjean, Julie; Beton, Nicolas; Gennero, Isabelle; Capilla, Florence; Neel, Benjamin G; Araki, Toshiyuki; Valet, Philippe; Tauber, Maithé; Salles, Jean-Pierre; Yart, Armelle; Edouard, Thomas

2018-04-12

Growth retardation is a constant feature of Noonan syndrome (NS) but its physiopathology remains poorly understood. We previously reported that hyperactive NS-causing SHP2 mutants impair the systemic production of insulin-like growth factor 1 (IGF1) through hyperactivation of the RAS/extracellular signal-regulated kinases (ERK) signalling pathway. Besides endocrine defects, a direct effect of these mutants on growth plate has not been explored, although recent studies have revealed an important physiological role for SHP2 in endochondral bone growth. We demonstrated that growth plate length was reduced in NS mice, mostly due to a shortening of the hypertrophic zone and to a lesser extent of the proliferating zone. These histological features were correlated with decreased expression of early chondrocyte differentiation markers, and with reduced alkaline phosphatase staining and activity, in NS murine primary chondrocytes. Although IGF1 treatment improved growth of NS mice, it did not fully reverse growth plate abnormalities, notably the decreased hypertrophic zone. In contrast, we documented a role of RAS/ERK hyperactivation at the growth plate level since 1) NS-causing SHP2 mutants enhance RAS/ERK activation in chondrocytes in vivo (NS mice) and in vitro (ATDC5 cells) and 2) inhibition of RAS/ERK hyperactivation by U0126 treatment alleviated growth plate abnormalities and enhanced chondrocyte differentiation. Similar effects were obtained by chronic treatment of NS mice with statins.In conclusion, we demonstrated that hyperactive NS-causing SHP2 mutants impair chondrocyte differentiation during endochondral bone growth through a local hyperactivation of the RAS/ERK signalling pathway, and that statin treatment may be a possible therapeutic approach in NS.

Engineering zonal cartilage through bioprinting collagen type II hydrogel constructs with biomimetic chondrocyte density gradient.

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Ren, Xiang; Wang, Fuyou; Chen, Cheng; Gong, Xiaoyuan; Yin, Li; Yang, Liu

2016-07-20

Cartilage tissue engineering is a promising approach for repairing and regenerating cartilage tissue. To date, attempts have been made to construct zonal cartilage that mimics the cartilaginous matrix in different zones. However, little attention has been paid to the chondrocyte density gradient within the articular cartilage. We hypothesized that the chondrocyte density gradient plays an important role in forming the zonal distribution of extracellular matrix (ECM). In this study, collagen type II hydrogel/chondrocyte constructs were fabricated using a bioprinter. Three groups were created according to the total cell seeding density in collagen type II pre-gel: Group A, 2 × 10(7) cells/mL; Group B, 1 × 10(7) cells/mL; and Group C, 0.5 × 10(7) cells/mL. Each group included two types of construct: one with a biomimetic chondrocyte density gradient and the other with a single cell density. The constructs were cultured in vitro and harvested at 0, 1, 2, and 3 weeks for cell viability testing, reverse-transcription quantitative PCR (RT-qPCR), biochemical assays, and histological analysis. We found that total ECM production was positively correlated with the total cell density in the early culture stage, that the cell density gradient distribution resulted in a gradient distribution of ECM, and that the chondrocytes' biosynthetic ability was affected by both the total cell density and the cell distribution pattern. Our results suggested that zonal engineered cartilage could be fabricated by bioprinting collagen type II hydrogel constructs with a biomimetic cell density gradient. Both the total cell density and the cell distribution pattern should be optimized to achieve synergistic biological effects.

Co-electrospun gelatin-poly(L-lactic acid) scaffolds: Modulation of mechanical properties and chondrocyte response as a function of composition

Energy Technology Data Exchange (ETDEWEB)

Torricelli, Paola [Preclinical and Surgical Studies Laboratory, Codivilla Putti Research Institute, Rizzoli Orthopaedic Institute, via di Barbiano, 1/10, 40136 Bologna (Italy); Laboratory of Biocompatibility, Innovative Technologies and Advanced Therapies—Department Rizzoli Research, Innovation, Technology, via di Barbiano, 1/10, 40136 Bologna (Italy); Gioffrè, Michela; Fiorani, Andrea; Panzavolta, Silvia [Department of Chemistry “G. Ciamician” and National Consortium of Materials Science and Technology (INSTM, Bologna RU), University of Bologna (Italy); Gualandi, Chiara [Department of Chemistry “G. Ciamician” and National Consortium of Materials Science and Technology (INSTM, Bologna RU), University of Bologna (Italy); Advanced Mechanics and Materials—Interdepartmental Center for Industrial Research (AMM ICIR), University of Bologna (Italy); Fini, Milena [Preclinical and Surgical Studies Laboratory, Codivilla Putti Research Institute, Rizzoli Orthopaedic Institute, via di Barbiano, 1/10, 40136 Bologna (Italy); Laboratory of Biocompatibility, Innovative Technologies and Advanced Therapies—Department Rizzoli Research, Innovation, Technology, via di Barbiano, 1/10, 40136 Bologna (Italy); Focarete, Maria Letizia, E-mail: marialetizia.focarete@unibo.it [Department of Chemistry “G. Ciamician” and National Consortium of Materials Science and Technology (INSTM, Bologna RU), University of Bologna (Italy); Health Sciences and Technologies—Interdepartmental Center for Industrial Research (HST-ICIR) (Italy); Bigi, Adriana [Department of Chemistry “G. Ciamician” and National Consortium of Materials Science and Technology (INSTM, Bologna RU), University of Bologna (Italy)

2014-03-01

Bio-synthetic scaffolds of interspersed poly(L-lactic acid) (PLLA) and gelatin (GEL) fibers are fabricated by co-electrospinning. Tailored PLLA/GEL compositions are obtained and GEL crosslinking with genipin provides for the maintenance of good fiber morphology. Scaffold tensile mechanical properties are intermediate between those of pure PLLA and GEL and vary as a function of PLLA content. Primary human chondrocytes grown on the scaffolds exhibit good proliferation and increased values of the differentiation parameters, especially for intermediate PLLA/GEL compositions. Mineralization tests enable the deposition of a uniform layer of poorly crystalline apatite onto the scaffolds, suggesting potential applications involving cartilage as well as cartilage–bone interface tissue engineering. - Highlights: • Bio-synthetic scaffolds of PLLA and gelatin are produced by co-electrospinning. • Scaffolds with tailored PLLA–gelatin composition are fabricated. • PLLA/gelatin ratio controls scaffold mechanical properties and mineralization. • Chondrocyte proliferation and differentiation are modulated. • Scaffolds are suitable for cartilage–bone interface tissue engineering.

Effects of Bauhinia championii (Benth.) Benth. polysaccharides on the proliferation and cell cycle of chondrocytes.

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Cai, Liangliang; Ye, Hongzhi; Yu, Fangrong; Li, Huiting; Chen, Jiashou; Liu, Xianxiang

2013-05-01

It has been recently shown that polysaccharides isolated from plants exhibit a number of beneficial therapeutic properties. Bauhinia championii (Benth.) Benth. has been widely used for the clinical treatment of knee osteoarthritis (OA) in China. However, the underlying molecular mechanisms of knee OA treatment have yet to be elucidated. In the present study, we investigated the effects of Bauhinia championii (Benth.) Benth. polysaccharides (BCBPs) on the proliferation and cell cycle of chondrocytes on 4-week-old male Sprague Dawley rats. Immunohistochemical staining was used to identify chondrocytes and an MTT assay was used to evaluate cell viability. Flow cytometry was used for cell cycle analysis. The mRNA and protein expression levels of cyclin D1, CDK4 and CDK6 in chondrocytes were detected using reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis, respectively. The data demonstrate that BCBP treatment increased the viability of chondrocytes. In addition, BCBP treatment reduced the cell population in the G0/G1 phase, whereas the cell population was increased in the S phase. Furthermore, BCBP treatment enhanced the expression of cyclin D1, CDK4 and CDK6. These results indicate that BCBP treatment promotes cell proliferation by accelerating the G1/S transition.

Trophic Effects of Mesenchymal Stem Cells in Chondrocyte Co-Cultures are Independent of Culture Conditions and Cell Sources

NARCIS (Netherlands)

Wu, Ling; Prins, H.J.; Helder, M.; van Blitterswijk, Clemens; Karperien, Hermanus Bernardus Johannes

2012-01-01

Earlier, we have shown that the increased cartilage production in pellet co-cultures of chondrocytes and bone marrow-derived mesenchymal stem cells (BM-MSCs) is due to a trophic role of the MSC in stimulating chondrocyte proliferation and matrix production rather than MSCs actively undergoing

Trophic effects of mesenchymal stem cells in chondrocyte co-cultures are independent of culture conditions and cell sources

NARCIS (Netherlands)

Wu, L.; Prins, H.J.; Helder, M.N.; van Blitterswijk, C.A.; Karperien, M.

2012-01-01

Earlier, we have shown that the increased cartilage production in pellet co-cultures of chondrocytes and bone marrow-derived mesenchymal stem cells (BM-MSCs) is due to a trophic role of the MSC in stimulating chondrocyte proliferation and matrix production rather than MSCs actively undergoing

Dlx5 Is a cell autonomous regulator of chondrocyte hypertrophy in mice and functionally substitutes for Dlx6 during endochondral ossification.

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Hui Zhu

Full Text Available The axial and appendicular skeleton of vertebrates develops by endochondral ossification, in which skeletogenic tissue is initially cartilaginous and the differentiation of chondrocytes via the hypertrophic pathway precedes the differentiation of osteoblasts and the deposition of a definitive bone matrix. Results from both loss-of-function and misexpression studies have implicated the related homeobox genes Dlx5 and Dlx6 as partially redundant positive regulators of chondrocyte hypertrophy. However, experimental perturbations of Dlx expression have either not been cell type specific or have been done in the context of endogenous Dlx5 expression. Thus, it has not been possible to conclude whether the effects on chondrocyte differentiation are cell autonomous or whether they are mediated by Dlx expression in adjacent tissues, notably the perichondrium. To address this question we first engineered transgenic mice in which Dlx5 expression was specifically restricted to immature and differentiating chondrocytes and not the perichondrium. Col2a1-Dlx5 transgenic embryos and neonates displayed accelerated chondrocyte hypertrophy and mineralization throughout the endochondral skeleton. Furthermore, this transgene specifically rescued defects of chondrocyte differentiation characteristic of the Dlx5/6 null phenotype. Based on these results, we conclude that the role of Dlx5 in the hypertrophic pathway is cell autonomous. We further conclude that Dlx5 and Dlx6 are functionally equivalent in the endochondral skeleton, in that the requirement for Dlx5 and Dlx6 function during chondrocyte hypertrophy can be satisfied with Dlx5 alone.

Trophic effects of adipose-tissue-derived and bone-marrow-derived mesenchymal stem cells enhance cartilage generation by chondrocytes in co-culture.

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Pleumeekers, M M; Nimeskern, L; Koevoet, J L M; Karperien, M; Stok, K S; van Osch, G J V M

2018-01-01

Combining mesenchymal stem cells (MSCs) and chondrocytes has great potential for cell-based cartilage repair. However, there is much debate regarding the mechanisms behind this concept. We aimed to clarify the mechanisms that lead to chondrogenesis (chondrocyte driven MSC-differentiation versus MSC driven chondroinduction) and whether their effect was dependent on MSC-origin. Therefore, chondrogenesis of human adipose-tissue-derived MSCs (hAMSCs) and bone-marrow-derived MSCs (hBMSCs) combined with bovine articular chondrocytes (bACs) was compared. hAMSCs or hBMSCs were combined with bACs in alginate and cultured in vitro or implanted subcutaneously in mice. Cartilage formation was evaluated with biochemical, histological and biomechanical analyses. To further investigate the interactions between bACs and hMSCs, (1) co-culture, (2) pellet, (3) Transwell® and (4) conditioned media studies were conducted. The presence of hMSCs-either hAMSCs or hBMSCs-increased chondrogenesis in culture; deposition of GAG was most evidently enhanced in hBMSC/bACs. This effect was similar when hMSCs and bAC were combined in pellet culture, in alginate culture or when conditioned media of hMSCs were used on bAC. Species-specific gene-expression analyses demonstrated that aggrecan was expressed by bACs only, indicating a predominantly trophic role for hMSCs. Collagen-10-gene expression of bACs was not affected by hBMSCs, but slightly enhanced by hAMSCs. After in-vivo implantation, hAMSC/bACs and hBMSC/bACs had similar cartilage matrix production, both appeared stable and did not calcify. This study demonstrates that replacing 80% of bACs by either hAMSCs or hBMSCs does not influence cartilage matrix production or stability. The remaining chondrocytes produce more matrix due to trophic factors produced by hMSCs.

Changes in the expression of collagen genes show two stages in chondrocyte differentiation in vitro

OpenAIRE

1988-01-01

This report deals with the quantitation of both mRNA and transcription activity of type I collagen gene and of three cartilage-specific collagens (types II, IX, and X) during in vitro differentiation of chick chondrocytes. Differentiation was obtained by transferal to suspension culture of dedifferentiated cells passaged for 3 wk as adherent cells. The type I collagen mRNA, highly represented in the dedifferentiated cells, rapidly decreased during chondrocyte differentiation. On the contrary,...

Hydroxylation of methylated DNA by TET1 in chondrocyte differentiation of C3H10T1/2 cells

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Ryo Ito

2016-03-01

Full Text Available DNA methylation is closely involved in the regulation of cellular differentiation, including chondrogenic differentiation of mesenchymal stem cells. Recent studies showed that Ten–eleven translocation (TET family proteins converted 5-methylcytosine (5mC to 5-hydroxymethylcytosine, 5-formylcytosine and 5carboxylcytosine by oxidation. These reactions constitute potential mechanisms for active demethylation of methylated DNA. However, the relationship between the DNA methylation patterns and the effects of TET family proteins in chondrocyte differentiation is still unclear. In this study, we showed that DNA hydroxylation of 5mC was increased during chondrocytic differentiation of C3H10T1/2 cells and that the expression of Tet1 was particularly enhanced. Moreover, knockdown experiments revealed that the downregulation of Tet1 expression caused decreases in chondrogenesis markers such as type 2 and type 10 collagens. Furthermore, we found that TET proteins had a site preference for hydroxylation of 5mC on the Insulin-like growth factor 1 (Igf1 promoter in chondrocytes. Taken together, we showed that the expression of Tet1 was specifically facilitated in chondrocyte differentiation and Tet1 can regulate chondrocyte marker gene expression presumably through its hydroxylation activity for DNA.

Protective Effect of Ginger (Zingiber officinale Roscoe) Extract against Oxidative Stress and Mitochondrial Apoptosis Induced by Interleukin-1β in Cultured Chondrocytes.

Science.gov (United States)

Hosseinzadeh, Azam; Bahrampour Juybari, Kobra; Fatemi, Mohammad Javad; Kamarul, Tunku; Bagheri, Aboulfazl; Tekiyehmaroof, Neda; Sharifi, Ali Mohammad

2017-01-01

The protective effects of ginger (Zingiber officinale Roscoe) extract on IL-1β-mediated oxidative stress and mitochondrial apoptosis were investigated in C28I2 human chondrocytes. The effects of various concentrations of ginger extract on C28I2 human chondrocyte viability were evaluated in order to obtain noncytotoxic concentrations of the drug by methylthiotetrazole assay. The cells were pretreated with 5 and 25 μg/mL ginger extract for 24 h, followed by incubation with IL-1β (10 ng/mL) for 24 h. The effects of ginger extract on IL-1β-induced intracellular reactive oxygen species (ROS) production and lipid peroxidation were examined. The mRNA expressions of antioxidant enzymes including catalase, superoxide dismutase-1, glutathione peroxidase-1, glutathione peroxidase-3, and glutathione peroxidase-4 were evaluated by reverse transcription polymerase chain reaction. The protein expressions of Bax, Bcl-2, and caspase-3 were analyzed by Western blotting. No cytotoxicity was observed at any concentration of ginger extract in C28I2 cells. Ginger extract pretreatment remarkably increased the gene expression of antioxidant enzymes and reduced the IL-1β-induced elevation of ROS, lipid peroxidation, the Bax/Bcl-2 ratio, and caspase-3 activity. Ginger extract could considerably reduce IL-1β-induced oxidative stress and consequent mitochondrial apoptosis as the major mechanisms of chondrocyte cell death. These beneficial effects of ginger extract may be due to its antioxidant properties. It may be considered as a natural herbal product to prevent OA-induced cartilage destruction in the clinical setting. © 2017 S. Karger AG, Basel.

Nitric Oxide Mediates Crosstalk between Interleukin 1β and WNT Signaling in Primary Human Chondrocytes by Reducing DKK1 and FRZB Expression.

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Zhong, Leilei; Schivo, Stefano; Huang, Xiaobin; Leijten, Jeroen; Karperien, Marcel; Post, Janine N

2017-11-22

Interleukin 1 beta (IL1β) and Wingless-Type MMTV Integration Site Family (WNT) signaling are major players in Osteoarthritis (OA) pathogenesis. Despite having a large functional overlap in OA onset and development, the mechanism of IL1β and WNT crosstalk has remained largely unknown. In this study, we have used a combination of computational modeling and molecular biology to reveal direct or indirect crosstalk between these pathways. Specifically, we revealed a mechanism by which IL1β upregulates WNT signaling via downregulating WNT antagonists, DKK1 and FRZB. In human chondrocytes, IL1β decreased the expression of Dickkopf-1 (DKK1) and Frizzled related protein (FRZB) through upregulation of nitric oxide synthase (iNOS), thereby activating the transcription of WNT target genes. This effect could be reversed by iNOS inhibitor 1400W, which restored DKK1 and FRZB expression and their inhibitory effect on WNT signaling. In addition, 1400W also inhibited both the matrix metalloproteinase (MMP) expression and cytokine-induced apoptosis. We concluded that iNOS/NO play a pivotal role in the inflammatory response of human OA through indirect upregulation of WNT signaling. Blocking NO production may inhibit the loss of the articular phenotype in OA by preventing downregulation of the expression of DKK1 and FRZB.

XBP1-Independent UPR Pathways Suppress C/EBP-β Mediated Chondrocyte Differentiation in ER-Stress Related Skeletal Disease.

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Trevor L Cameron

2015-09-01

Full Text Available Schmid metaphyseal chondrodysplasia (MCDS involves dwarfism and growth plate cartilage hypertrophic zone expansion resulting from dominant mutations in the hypertrophic zone collagen, Col10a1. Mouse models phenocopying MCDS through the expression of an exogenous misfolding protein in the endoplasmic reticulum (ER in hypertrophic chondrocytes have demonstrated the central importance of ER stress in the pathology of MCDS. The resultant unfolded protein response (UPR in affected chondrocytes involved activation of canonical ER stress sensors, IRE1, ATF6, and PERK with the downstream effect of disrupted chondrocyte differentiation. Here, we investigated the role of the highly conserved IRE1/XBP1 pathway in the pathology of MCDS. Mice with a MCDS collagen X p.N617K knock-in mutation (ColXN617K were crossed with mice in which Xbp1 was inactivated specifically in cartilage (Xbp1CartΔEx2, generating the compound mutant, C/X. The severity of dwarfism and hypertrophic zone expansion in C/X did not differ significantly from ColXN617K, revealing surprising redundancy for the IRE1/XBP1 UPR pathway in the pathology of MCDS. Transcriptomic analyses of hypertrophic zone cartilage identified differentially expressed gene cohorts in MCDS that are pathologically relevant (XBP1-independent or pathologically redundant (XBP1-dependent. XBP1-independent gene expression changes included large-scale transcriptional attenuation of genes encoding secreted proteins and disrupted differentiation from proliferative to hypertrophic chondrocytes. Moreover, these changes were consistent with disruption of C/EBP-β, a master regulator of chondrocyte differentiation, by CHOP, a transcription factor downstream of PERK that inhibits C/EBP proteins, and down-regulation of C/EBP-β transcriptional co-factors, GADD45-β and RUNX2. Thus we propose that the pathology of MCDS is underpinned by XBP1 independent UPR-induced dysregulation of C/EBP-β-mediated chondrocyte differentiation

Co-culture of chondrocytes and bone marrow mesenchymal stem cells in vitro enhances the expression of cartilaginous extracellular matrix components

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Chang Qing

2011-04-01

Full Text Available Chondrocytes and bone marrow mesenchymal stem cells (BMSCs are frequently used as seed cells in cartilage tissue engineering. In the present study, we determined if the co-culture of rabbit articular chondrocytes and BMSCs in vitro promotes the expression of cartilaginous extracellular matrix and, if so, what is the optimal ratio of the two cell types. Cultures of rabbit articular chondrocytes and BMSCs were expanded in vitro and then cultured individually or at a chondrocyte:BMSC ratio of 4:1, 2:1, 1:1, 1:2, 1:4 for 21 days and cultured in DMEM/F12. BMSCs were cultured in chondrogenic induction medium. Quantitative real-time RT-PCR and Western blot were used to evaluate gene expression. In the co-cultures, type II collagen and aggrecan expression increased on days 14 and 21. At the mRNA level, the expression of type II collagen and aggrecan on day 21 was much higher in the 4:1, 2:1, and 1:1 groups than in either the articular chondrocyte group or the induced BMSC group, and the best ratio of co-culture groups seems to be 2:1. Also on day 21, the expression of type II collagen and aggrecan proteins in the 2:1 group was much higher than in all other groups. The results demonstrate that the co-culture of rabbit chondrocytes and rabbit BMSCs at defined ratios can promote the expression of cartilaginous extracellular matrix. The optimal cell ratio appears to be 2:1 (chondrocytes:BMSCs. This approach has potential applications in cartilage tissue engineering since it provides a protocol for maintaining and promoting seed-cell differentiation and function.

Co-culture of chondrocytes and bone marrow mesenchymal stem cells in vitro enhances the expression of cartilaginous extracellular matrix components.

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Qing, Chang; Wei-ding, Cui; Wei-min, Fan

2011-04-01

Chondrocytes and bone marrow mesenchymal stem cells (BMSCs) are frequently used as seed cells in cartilage tissue engineering. In the present study, we determined if the co-culture of rabbit articular chondrocytes and BMSCs in vitro promotes the expression of cartilaginous extracellular matrix and, if so, what is the optimal ratio of the two cell types. Cultures of rabbit articular chondrocytes and BMSCs were expanded in vitro and then cultured individually or at a chondrocyte:BMSC ratio of 4:1, 2:1, 1:1, 1:2, 1:4 for 21 days and cultured in DMEM/F12. BMSCs were cultured in chondrogenic induction medium. Quantitative real-time RT-PCR and Western blot were used to evaluate gene expression. In the co-cultures, type II collagen and aggrecan expression increased on days 14 and 21. At the mRNA level, the expression of type II collagen and aggrecan on day 21 was much higher in the 4:1, 2:1, and 1:1 groups than in either the articular chondrocyte group or the induced BMSC group, and the best ratio of co-culture groups seems to be 2:1. Also on day 21, the expression of type II collagen and aggrecan proteins in the 2:1 group was much higher than in all other groups. The results demonstrate that the co-culture of rabbit chondrocytes and rabbit BMSCs at defined ratios can promote the expression of cartilaginous extracellular matrix. The optimal cell ratio appears to be 2:1 (chondrocytes:BMSCs). This approach has potential applications in cartilage tissue engineering since it provides a protocol for maintaining and promoting seed-cell differentiation and function.

Type II collagen peptide is able to accelerate embryonic chondrocyte differentiation: an association with articular cartilage matrix resorption in osteoarthrosis

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Elena Vasil'evna Chetina

2010-01-01

Conclusion. The effect of CP on gene expression and collagen decomposition activity depends on the morphotype of embryonic chondrocytes. Lack of effect of CP on collagen decomposition activity in both the embryonic hypertrophic chondrocytes and the cartilage explants from OA patients supports the hypothesis that the hypertrophic morphotype is a dominant morphotype of articular chondrocytes in OA. Moreover, collagen decomposition products can be involved in the resorption of matrix in OA and in the maintenance of chronic nature of the pathology.

Effects of non-steroidal anti-inflammatory drugs on cell proliferation and death in cultured epiphyseal-articular chondrocytes of fetal rats

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Chang, J.-K.; Wu, S.-C.; Wang, G.-J.

2006-01-01

Previous reports indicated that non-steroidal anti-inflammatory drugs (NSAIDs) suppress bone repair. Our previous study further found that ketorolac delayed the endochondral bone formation, and the critical effective timing was at the early stage of repair. Furthermore, we found that NSAIDs suppressed proliferation and induced cell death of cultured osteoblasts. In this study, we hypothesized that chondrocytic proliferation and death, which plays an important role at the early stage of endochondral bone formation, might be affected by NSAIDs. Non-selective NSAIDs, indomethacin, ketorolac, diclofenac and piroxicam; cyclooxygenase-2 (COX-2) selective NSAIDs, celecoxib and DFU (an analog of rofecoxib); prostaglandins (PGs), PGE1, PGE2 and PGF2α; and each NSAID plus each PG were tested. The effects of NSAIDs on proliferation, cell cycle kinetics, cytotoxicity and cell death of epiphyseal-articular chondrocytes of fetal rats were examined. The results showed that all the tested NSAIDs, except DFU, inhibited thymidine incorporation of chondrocytes at a concentration range (10 -8 to 10 -4 M) covering the theoretic therapeutic concentrations. Cell cycle was arrested by NSAIDs at the G /G 1 phase. Upon a 24 h treatment, LDH leakage and cell death (both apoptosis and necrosis) were significantly induced by the four non-selective NSAIDs in chondrocyte cultures. However, COX-2 inhibitors revealed non-significant effects on cytotoxicity of chondrocytes except higher concentration of celecoxib (10 -4 M). Replenishments of PGE1, PGE2 or PGF2α could not reverse the effects of NSAIDs on chondrocytic proliferation and cytotoxicity. In this study, we found that therapeutic concentrations of non-selective NSAIDs caused proliferation suppression and cell death of chondrocytes, suggesting these adverse effects may be one of the reasons that NSAIDs delay the endochondral ossification during bone repair found in previous studies. Furthermore, these effects of NSAIDs may act via PG

Mild electrical stimulation with heat stimulation increase heat shock protein 70 in articular chondrocyte.

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Hiraoka, Nobuyuki; Arai, Yuji; Takahashi, Kenji A; Mazda, Osam; Kishida, Tsunao; Honjo, Kuniaki; Tsuchida, Shinji; Inoue, Hiroaki; Morino, Saori; Suico, Mary Ann; Kai, Hirofumi; Kubo, Toshikazu

2013-06-01

The objective of this study is to investigate the effects of mild electrical stimulation (MES) and heat stress (HS) on heat shock protein 70 (HSP70), that protects chondrocytes and enhances cartilage matrix metabolism, in chondrocyte and articular cartilage. Rabbit articular chondrocytes were treated with MES and/or HS. The safeness was assessed by LDH assay and morphology. HSP70 protein, ubiquitinated proteins and HSP70 mRNA were examined by Western blotting and real-time PCR. Rat knee joints were treated with MES and/or HS. HSP70 protein, ubiquitinated proteins, HSP70 mRNA and proteoglycan core protein (PG) mRNA in articular cartilage were investigated. In vitro, HS increased HSP70 mRNA and HSP70 protein. MES augmented ubiquitinated protein and HSP70 protein, but not HSP70 mRNA. MES + HS raised HSP70 mRNA and ubiquitinated protein, and significantly increased HSP70 protein. In vivo, HS and MES + HS treatment augmented HSP70 mRNA. HS modestly augmented HSP70 protein. MES + HS significantly increased HSP70 protein and ubiquitinated proteins. PG mRNA was markedly raised by MES + HS. This study demonstrated that MES, in combination with HS, increases HSP70 protein in chondrocytes and articular cartilage, and promotes cartilage matrix metabolism in articular cartilage. MES in combination with HS can be a novel physical therapy for osteoarthritis by inducing HSP70 in articular cartilage. Copyright © 2013 Orthopaedic Research Society.

Treatment of articular cartilage lesions of the knee by microfracture or autologous chondrocyte implantation: a systematic review.

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Oussedik, Sam; Tsitskaris, Konstantinos; Parker, David

2015-04-01

We performed a systematic review of the treatment of articular cartilage lesions of the knee by microfracture or autologous chondrocyte implantation to determine the differences in patient outcomes after these procedures. We searched PubMed/Medline, Embase, and The Cochrane Library databases in the period from January 10 through January 20, 2013, and included 34 articles in our qualitative analysis. All studies showed improvement in outcome scores in comparison with baseline values, regardless of the treatment modality. The heterogeneity of the results presented in the studies precluded a meta-analysis. Microfracture appears to be effective in smaller lesions and is usually associated with a greater proportion of fibrocartilage production, which may have an effect on durability and eventual failure. Autologous chondrocyte implantation is an effective treatment that may result in a greater proportion of hyaline-like tissue at the repair site, which may in turn have a beneficial effect on durability and failure; it appears to be effective in larger lesions. Autologous chondrocyte implantation with periosteum has been shown to be associated with symptomatic cartilage hypertrophy more frequently than autologous chondrocyte implantation with collagen membrane. Matrix-associated autologous chondrocyte implantation is technically less challenging than the other techniques available, and in lesions greater than 4 cm(2), it has been shown to be more effective than microfracture. Level IV, systematic review of Level I-IV studies. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Effect of stiffness of chitosan-hyaluronic acid dialdehyde hydrogels on the viability and growth of encapsulated chondrocytes.

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V Thomas, Lynda; Vg, Rahul; D Nair, Prabha

2017-11-01

Substrate elasticity or stiffness can influence the phenotypic and functional characteristics of chondrocytes. This work aimed to study the effect of varying stiffness compositions of a two-component injectable hydrogel based on chitosan (CH) and oxidized hyaluronic acid (HDA) on the growth and functionality of encapsulated chondrocytes. Three different ratios of the gel were prepared (10:1,10:3 and 10:5 CH-HDA) and characterized. The stiffness of the gels was evaluated from the force displacement curves using force spectroscopy AFM analysis. Rabbit articular chondrocytes were harvested and the cells from Passage 2 to 4 were used for the encapsulation study. The viability and ECM production of encapsulated chondrocytes were assessed at 7day, 14day and 28day post culture. The results of the study show that as the ratio of hyaluronic acid dialdehyde component was increased, the stiffness of the gels increased from 130.78±19.83kPa to 181.47±19.77kPa which was also evidenced from the decrease in gelling time. Although there was an increase in the percentage of viable encapsulated cells which also maintained the spherical phenotype in the less stiff gels, decreased expression of ECM markers- Collagen type II and Glycosaminoglycans was observed compared to the stiffer gels. These findings indicate that gel stiffness strongly impacts the chondrocyte microenvironment both in maintenance of phenotypic integrity and ECM production. Copyright © 2017. Published by Elsevier B.V.

MicroRNA-140 Provides Robustness to the Regulation of Hypertrophic Chondrocyte Differentiation by the PTHrP-HDAC4 Pathway.

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Papaioannou, Garyfallia; Mirzamohammadi, Fatemeh; Lisse, Thomas S; Nishimori, Shigeki; Wein, Marc N; Kobayashi, Tatsuya

2015-06-01

Growth plate chondrocytes go through multiple differentiation steps and eventually become hypertrophic chondrocytes. The parathyroid hormone (PTH)-related peptide (PTHrP) signaling pathway plays a central role in regulation of hypertrophic differentiation, at least in part, through enhancing activity of histone deacetylase 4 (HDAC4), a negative regulator of MEF2 transcription factors that drive hypertrophy. We have previously shown that loss of the chondrocyte-specific microRNA (miRNA), miR-140, alters chondrocyte differentiation including mild acceleration of hypertrophic differentiation. Here, we provide evidence that miR-140 interacts with the PTHrP-HDAC4 pathway to control chondrocyte differentiation. Heterozygosity of PTHrP or HDAC4 substantially impaired animal growth in miR-140 deficiency, whereas these mutations had no effect in the presence of miR-140. miR-140-deficient chondrocytes showed increased MEF2C expression with normal levels of total and phosphorylated HDAC4, indicating that the miR-140 pathway merges with the PTHrP-HDAC4 pathway at the level of MEF2C. miR-140 negatively regulated p38 mitogen-activated protein kinase (MAPK) signaling, and inhibition of p38 MAPK signaling reduced MEF2C expression. These results demonstrate that miR-140 ensures the robustness of the PTHrP/HDAC4 regulatory system by suppressing MEF2C-inducing stimuli. © 2014 American Society for Bone and Mineral Research © 2015 American Society for Bone and Mineral Research. © 2014 American Society for Bone and Mineral Research.

Similar properties of chondrocytes from osteoarthritis joints and mesenchymal stem cells from healthy donors for tissue engineering of articular cartilage.

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Amilton M Fernandes

Full Text Available Lesions of hyaline cartilage do not heal spontaneously, and represent a therapeutic challenge. In vitro engineering of articular cartilage using cells and biomaterials may prove to be the best solution. Patients with osteoarthritis (OA may require tissue engineered cartilage therapy. Chondrocytes obtained from OA joints are thought to be involved in the disease process, and thus to be of insufficient quality to be used for repair strategies. Bone marrow (BM derived mesenchymal stem cells (MSCs from healthy donors may represent an alternative cell source. We have isolated chondrocytes from OA joints, performed cell culture expansion and tissue engineering of cartilage using a disc-shaped alginate scaffold and chondrogenic differentiation medium. We performed real-time reverse transcriptase quantitative PCR and fluorescence immunohistochemistry to evaluate mRNA and protein expression for a range of molecules involved in chondrogenesis and OA pathogenesis. Results were compared with those obtained by using BM-MSCs in an identical tissue engineering strategy. Finally the two populations were compared using genome-wide mRNA arrays. At three weeks of chondrogenic differentiation we found high and similar levels of hyaline cartilage-specific type II collagen and fibrocartilage-specific type I collagen mRNA and protein in discs containing OA and BM-MSC derived chondrocytes. Aggrecan, the dominant proteoglycan in hyaline cartilage, was more abundantly distributed in the OA chondrocyte extracellular matrix. OA chondrocytes expressed higher mRNA levels also of other hyaline extracellular matrix components. Surprisingly BM-MSC derived chondrocytes expressed higher mRNA levels of OA markers such as COL10A1, SSP1 (osteopontin, ALPL, BMP2, VEGFA, PTGES, IHH, and WNT genes, but lower levels of MMP3 and S100A4. Based on the results presented here, OA chondrocytes may be suitable for tissue engineering of articular cartilage.

Hydroxychloroquine induces inhibition of collagen type II and oligomeric matrix protein COMP expression in chondrocytes

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Tao Li

2016-06-01

Full Text Available The aim of this study was to investigate the effect of hydroxychloroquine on the level of collagen type II and oligomeric matrix protein COMP expression in chondrocytes of knee osteoarthritis. The rate of growth in cartilage cells was analyzed using MTT assay whereas the Col-2 and COMP expression levels were detected by RT-PCR and Western blotting analyses. For the determination of MMP-13 expression, ELISA test was used. The results revealed no significant change in the rate of cartilage cell proliferation in hydroxychloroquine-treated compared to untreated cells. Hydroxychloro-quine treatment exhibited concentration- and time-dependent effect on the inhibition of collagen type II and COMP expression in chondrocytes. However, its treatment caused a significant enhancement in the expression levels of MMP-13 compared to the untreated cells. Therefore, hydroxychloro-quine promotes expression of MMP-13 and reduces collagen type II and COMP expression levels in chondrocytes without any significant change in the growth of cells.

Subchondral Bone Plate Thickening Precedes Chondrocyte Apoptosis and Cartilage Degradation in Spontaneous Animal Models of Osteoarthritis

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Zamli, Zaitunnatakhin; Robson Brown, Kate; Tarlton, John F.; Adams, Mike A.; Torlot, Georgina E.; Cartwright, Charlie; Cook, William A.; Vassilevskaja, Kristiina; Sharif, Mohammed

2014-01-01

Osteoarthritis (OA) is the most common joint disorder characterised by bone remodelling and cartilage degradation and associated with chondrocyte apoptosis. These processes were investigated at 10, 16, 24, and 30 weeks in Dunkin Hartley (DH) and Bristol Strain 2 (BS2) guinea pigs that develop OA spontaneously. Both strains had a more pronounced chondrocyte apoptosis, cartilage degradation, and subchondral bone changes in the medial than the lateral side of the tibia, and between strains, the ...

Statins do not inhibit the FGFR signaling in chondrocytes

Czech Academy of Sciences Publication Activity Database

Fafílek, B.; Hampl, Marek; Říčánková, N.; Veselá, Iva; Bálek, L.; Kunová Bosáková, M.; Gudernová, I.; Vařecha, M.; Buchtová, Marcela; Krejčí, P.

2017-01-01

Roč. 25, č. 9 (2017), s. 1522-1530 ISSN 1063-4584 R&D Projects: GA ČR(CZ) GA14-31540S Grant - others:GA MŠk(CZ) LH12004 Institutional support: RVO:67985904 Keywords : statins * FGF signaling * chondrocytes Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Developmental biology Impact factor: 4.742, year: 2016

The ECM-Cell Interaction of Cartilage Extracellular Matrix on Chondrocytes

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Yue Gao

2014-01-01

Full Text Available Cartilage extracellular matrix (ECM is composed primarily of the network type II collagen (COLII and an interlocking mesh of fibrous proteins and proteoglycans (PGs, hyaluronic acid (HA, and chondroitin sulfate (CS. Articular cartilage ECM plays a crucial role in regulating chondrocyte metabolism and functions, such as organized cytoskeleton through integrin-mediated signaling via cell-matrix interaction. Cell signaling through integrins regulates several chondrocyte functions, including differentiation, metabolism, matrix remodeling, responses to mechanical stimulation, and cell survival. The major signaling pathways that regulate chondrogenesis have been identified as wnt signal, nitric oxide (NO signal, protein kinase C (PKC, and retinoic acid (RA signal. Integrins are a large family of molecules that are central regulators in multicellular biology. They orchestrate cell-cell and cell-matrix adhesive interactions from embryonic development to mature tissue function. In this review, we emphasize the signaling molecule effect and the biomechanics effect of cartilage ECM on chondrogenesis.

Effects of parathyroid hormone and calcitonin on alkaline phosphatase activity and matrix calcification in rabbit growth-plate chondrocyte cultures

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Kato, Y.; Shimazu, A.; Nakashima, K.; Suzuki, F.; Jikko, A.; Iwamoto, M. (Osaka Univ. (Japan))

1990-07-01

The effects of PTH and calcitonin (CT) on the expression of mineralization-related phenotypes by chondrocytes were examined. In cultures of pelleted growth-plate chondrocytes. PTH caused 60-90% decreases in alkaline phosphatase activity, the incorporation of {sup 45}Ca into insoluble material, and the calcium content during the post-mitotic stage. These effects of PTH were dose-dependent and reversible. In contrast, CT increased alkaline phosphatase activity, {sup 45}Ca incorporation into insoluble material, and the calcium content by 1.4- to 1.8-fold. These observations suggest that PTH directly inhibits the expression of the mineralization-related phenotypes by growth-plate chondrocytes, and that CT has the opposite effects.

Streptococcus pyogenes degrades extracellular matrix in chondrocytes via MMP-13

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Sakurai, Atsuo; Okahashi, Nobuo; Maruyama, Fumito; Ooshima, Takashi; Hamada, Shigeyuki; Nakagawa, Ichiro

2008-01-01

Group A streptococcus (GAS) causes a wide range of human diseases, including bacterial arthritis. The pathogenesis of arthritis is characterized by synovial proliferation and the destruction of cartilage and subchondral bone in joints. We report here that GAS strain JRS4 invaded a chondrogenic cell line ATDC5 and induced the degradation of the extracellular matrix (ECM), whereas an isogenic mutant of JRS4 lacking a fibronectin-binding protein, SAM1, failed to invade the chondrocytes or degrade the ECM. Reverse transcription-PCR and Western blot analysis revealed that the expression of matrix metalloproteinase (MMP)-13 was strongly elevated during the infection with GAS. A reporter assay revealed that the activation of the AP-1 transcription factor and the phosphorylation of c-Jun terminal kinase participated in MMP-13 expression. These results suggest that MMP-13 plays an important role in the destruction of infected joints during the development of septic arthritis

HIF-1α-induced HSP70 regulates anabolic responses in articular chondrocytes under hypoxic conditions.

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Tsuchida, Shinji; Arai, Yuji; Takahashi, Kenji A; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Inoue, Hiroaki; Ikoma, Kazuya; Ueshima, Keiichiro; Matsuki, Tomohiro; Mazda, Osam; Kubo, Toshikazu

2014-08-01

We assessed whether heat shock protein 70 (HSP70) is involved in hypoxia inducible factor 1 alpha (HIF-1α)-dependent anabolic pathways in articular chondrocytes under hypoxic conditions. Primary rabbit chondrocytes were cultured under normoxia (20% oxygen condition) or hypoxia (1% oxygen condition). Alternatively, cells cultured under normoxia were treated with CoCl2 , which induces HIF-1α, to simulate hypoxia, or transfected with siRNAs targeting HIF-1α (si-HIF-1α) and HSP70 (si-HSP70) under hypoxia. HSP70 expression was enhanced by the increased expression of HIF-1α under hypoxia or simulated hypoxia, but not in the presence of si-HIF-1α. Hypoxia-induced overexpression of ECM genes was significantly suppressed by si-HIF-1α or si-HSP70. Cell viability positively correlated with hypoxia, but transfection with si-HIF-1α or si-HSP70 abrogated the chondroprotective effects of hypoxia. Although LDH release from sodium nitroprusside-treated cells and the proportion of TUNEL positive cells were decreased under hypoxia, transfection with si-HIF-1α or si-HSP70 almost completely blocked these effects. These findings indicated that HIF-1α-induced HSP70 overexpression increased the expression levels of ECM genes and cell viability, and protected chondrocytes from apoptosis. HIF-1α may regulate the anabolic effects of chondrocytes under hypoxic conditions by regulating HSP70 expression. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

BMP and Ihh/PTHrP signaling interact to coordinate chondrocyte proliferation and differentiation.

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Minina, E; Wenzel, H M; Kreschel, C; Karp, S; Gaffield, W; McMahon, A P; Vortkamp, A

2001-11-01

During endochondral ossification, two secreted signals, Indian hedgehog (Ihh) and parathyroid hormone-related protein (PTHrP), have been shown to form a negative feedback loop regulating the onset of hypertrophic differentiation of chondrocytes. Bone morphogenetic proteins (BMPs), another family of secreted factors regulating bone formation, have been implicated as potential interactors of the Ihh/PTHrP feedback loop. To analyze the relationship between the two signaling pathways, we used an organ culture system for limb explants of mouse and chick embryos. We manipulated chondrocyte differentiation by supplementing these cultures either with BMP2, PTHrP and Sonic hedgehog as activators or with Noggin and cyclopamine as inhibitors of the BMP and Ihh/PTHrP signaling systems. Overexpression of Ihh in the cartilage elements of transgenic mice results in an upregulation of PTHrP expression and a delayed onset of hypertrophic differentiation. Noggin treatment of limbs from these mice did not antagonize the effects of Ihh overexpression. Conversely, the promotion of chondrocyte maturation induced by cyclopamine, which blocks Ihh signaling, could not be rescued with BMP2. Thus BMP signaling does not act as a secondary signal of Ihh to induce PTHrP expression or to delay the onset of hypertrophic differentiation. Similar results were obtained using cultures of chick limbs. We further investigated the role of BMP signaling in regulating proliferation and hypertrophic differentiation of chondrocytes and identified three functions of BMP signaling in this process. First we found that maintaining a normal proliferation rate requires BMP and Ihh signaling acting in parallel. We further identified a role for BMP signaling in modulating the expression of IHH: Finally, the application of Noggin to mouse limb explants resulted in advanced differentiation of terminally hypertrophic cells, implicating BMP signaling in delaying the process of hypertrophic differentiation itself. This

Effects of low molecular weight hyaluronan combined with carprofen on canine osteoarthritis articular chondrocytes and cartilage explants in vitro.

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Euppayo, Thippaporn; Siengdee, Puntita; Buddhachat, Kittisak; Pradit, Waranee; Viriyakhasem, Nawarat; Chomdej, Siriwadee; Ongchai, Siriwan; Harada, Yasuji; Nganvongpanit, Korakot

2015-09-01

Intra-articular injection with non-steroidal anti-inflammatory drugs (NSAIDs) is used to treat inflammatory joint disease, but the side effects of NSAIDs include chondrotoxicity. Hyaluronan has shown positive effects on chondrocytes by reducing apoptosis and increasing proteoglycan synthesis. The purposes of this study were to evaluate the effects of low molecular weight hyaluronan (low MW HA), carprofen 25 mg/ml, carprofen 12.5 mg/ml, and a combination of HA and carprofen on canine osteoarthritis (OA) articular chondrocytes and a cartilage explant model in terms of cell viability, extracellular matrix remaining, and gene expression after exposure. In chondrocyte culture, MTT assay was used to evaluate the chondrotoxicity of IC50 and IC80 of carprofen with HA. In cartilage explant culture, two kinds of extracellular matrix (uronic acid and collagen) remaining in cartilage were used to evaluate cartilage damage for 14 d after treatment. Expression of COL2A1, AGG, and MMP3 was used to evaluate the synthesis and degradation of the matrix for 7 d after treatment. In chondrocyte culture, low MW HA could preserve OA chondrocyte viability but could not reduce the chondrotoxicity level of carprofen (P carprofen caused less destruction of uronic acid and collagen structure when compared with the control (P carprofen resulted in higher COL2A1 and AGG expression levels than carprofen alone.

In Vitro Expression of the Extracellular Matrix Components Aggrecan, Collagen Types I and II by Articular Cartilage-Derived Chondrocytes.

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Schneevoigt, J; Fabian, C; Leovsky, C; Seeger, J; Bahramsoltani, M

2017-02-01

The extracellular matrix (ECM) of hyaline cartilage is perfectly suited to transmit articular pressure load to the subchondral bone. Pressure is transferred by a high amount of aggrecan-based proteoglycans and collagen type II fibres in particular. After any injury, the hyaline cartilage is replaced by fibrocartilage, which is low in proteoglycans and contains collagen type I predominantly. Until now, long-term results of therapeutic procedures including cell-based therapies like autologous chondrocyte transplantation (ACT) lead to a replacement tissue meeting the composition of fibrocartilage. Therefore, it is of particular interest to discover how and to what extent isolation and in vitro cultivation of chondrocytes affect the cells and their expression of ECM components. Hyaline cartilage-derived chondrocytes were cultivated in vitro and observed microscopically over a time period of 35 days. The expression of collagen type I, collagen type II and aggrecan was analysed using RT-qPCR and Western blot at several days of cultivation. Chondrocytes presented a longitudinal shape for the entire cultivation period. While expression of collagen type I prevailed within the first days, only prolonged cultivation led to an increase in collagen type II and aggrecan expression. The results indicate that chondrocyte isolation and in vitro cultivation lead to a dedifferentiation at least to the stage of chondroprogenitor cells. © 2016 Blackwell Verlag GmbH.

Pulsed electromagnetic fields increased the anti-inflammatory effect of A₂A and A₃ adenosine receptors in human T/C-28a2 chondrocytes and hFOB 1.19 osteoblasts.

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Fabrizio Vincenzi

Full Text Available Adenosine receptors (ARs have an important role in the regulation of inflammation and their activation is involved in the inhibition of pro-inflammatory cytokine release. The effects of pulsed electromagnetic fields (PEMFs on inflammation have been reported and we have demonstrated that PEMFs increased A2A and A3AR density and functionality in different cell lines. Chondrocytes and osteoblasts are two key cell types in the skeletal system that play important role in cartilage and bone metabolism representing an interesting target to study the effect of PEMFs. The primary aim of the present study was to evaluate if PEMF exposure potentiated the anti-inflammatory effect of A2A and/or A3ARs in T/C-28a2 chondrocytes and hFOB 1.19 osteoblasts. Immunofluorescence, mRNA analysis and saturation binding assays revealed that PEMF exposure up-regulated A2A and A3AR expression. A2A and A3ARs were able to modulate cAMP production and cell proliferation. The activation of A2A and A3ARs resulted in the decrease of some of the most relevant pro-inflammatory cytokine release such as interleukin (IL-6 and IL-8, following the treatment with IL-1β as an inflammatory stimuli. In human chondrocyte and osteoblast cell lines, the inhibitory effect of A2A and A3AR stimulation on the release of prostaglandin E2 (PGE2, an important lipid inflammatory mediator, was observed. In addition, in T/C-28a2 cells, the activation of A2A or A3ARs elicited an inhibition of vascular endothelial growth factor (VEGF secretion. In hFOB 1.19 osteoblasts, PEMF exposure determined an increase of osteoprotegerin (OPG production. The effect of the A2A or A3AR agonists in the examined cells was enhanced in the presence of PEMFs and completely blocked by using well-known selective antagonists. These results demonstrated that PEMF exposure significantly increase the anti-inflammatory effect of A2A or A3ARs suggesting their potential therapeutic use in the therapy of inflammatory bone and joint

Age-Related Alterations in Signaling Pathways in Articular Chondrocytes: Implications for the Pathogenesis and Progression of Osteoarthritis - A Mini-Review.

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van der Kraan, Peter; Matta, Csaba; Mobasheri, Ali

2017-01-01

Musculoskeletal conditions are a major burden on individuals, healthcare systems, and social care systems throughout the world, with indirect costs having a predominant economic impact. Aging is a major contributing factor to the development and progression of arthritic and musculoskeletal diseases. Indeed, aging and inflammation (often referred to as 'inflammaging') are critical risk factors for the development of osteoarthritis (OA), which is one of the most common forms of joint disease. The term 'chondrosenescence' has recently been introduced to define the age-dependent deterioration of chondrocyte function and how it undermines cartilage function in OA. An important component of chondrosenescence is the age-related deregulation of subcellular signaling pathways in chondrocytes. This mini-review discusses the role of age-related alterations in chondrocyte signaling pathways. We focus our attention on two major areas: age-dependent alterations in transforming growth factor-β signaling and changes in protein kinase and phosphoprotein phosphatase activities in aging chondrocytes. A better understanding of the basic signaling mechanisms underlying aging in chondrocytes is likely to facilitate the development of new therapeutic and preventive strategies for OA and a range of other age-related osteoarticular disorders. © 2016 The Author(s) Published by S. Karger AG, Basel.

Mutations in fam20b and xylt1 reveal that cartilage matrix controls timing of endochondral ossification by inhibiting chondrocyte maturation.

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B Frank Eames

2011-08-01

Full Text Available Differentiating cells interact with their extracellular environment over time. Chondrocytes embed themselves in a proteoglycan (PG-rich matrix, then undergo a developmental transition, termed "maturation," when they express ihh to induce bone in the overlying tissue, the perichondrium. Here, we ask whether PGs regulate interactions between chondrocytes and perichondrium, using zebrafish mutants to reveal that cartilage PGs inhibit chondrocyte maturation, which ultimately dictates the timing of perichondral bone development. In a mutagenesis screen, we isolated a class of mutants with decreased cartilage matrix and increased perichondral bone. Positional cloning identified lesions in two genes, fam20b and xylosyltransferase1 (xylt1, both of which encode PG synthesis enzymes. Mutants failed to produce wild-type levels of chondroitin sulfate PGs, which are normally abundant in cartilage matrix, and initiated perichondral bone formation earlier than their wild-type siblings. Primary chondrocyte defects might induce the bone phenotype secondarily, because mutant chondrocytes precociously initiated maturation, showing increased and early expression of such markers as runx2b, collagen type 10a1, and ihh co-orthologs, and ihha mutation suppressed early perichondral bone in PG mutants. Ultrastructural analyses demonstrated aberrant matrix organization and also early cellular features of chondrocyte hypertrophy in mutants. Refining previous in vitro reports, which demonstrated that fam20b and xylt1 were involved in PG synthesis, our in vivo analyses reveal that these genes function in cartilage matrix production and ultimately regulate the timing of skeletal development.

Calcitonin directly attenuates collagen type II degradation by inhibition of matrix metalloproteinase expression and activity in articular chondrocytes

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Sondergaard, B C; Wulf, H; Henriksen, K

2006-01-01

OBJECTIVE: Calcitonin was recently reported to counter progression of cartilage degradation in an experimental model of osteoarthritis, and the effects were primarily suggested to be mediated by inhibition of subchondral bone resorption. We investigated direct effects of calcitonin on chondrocytes...... by assessing expression of the receptor and pharmacological effects on collagen type II degradation under ex vivo and in vivo conditions. METHODS: Localization of the calcitonin receptor on articular chondrocytes was investigated by immunohistochemistry, and the expression by reverse transcriptase polymerase.......0001-1 microM]. In vivo, cartilage degradation was investigated in ovariectomized (OVX) rats administered with oral calcitonin [2 mg/kg calcitonin] for 9 weeks. RESULTS: The calcitonin receptor was identified in articular chondrocytes by immunohistochemistry and RT-PCR. Calcitonin concentration...

Enhanced Chondrocyte Proliferation in a Prototyped Culture System with Wave-Induced Agitation

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Pilarek Maciej

2017-06-01

Full Text Available One of the actual challenges in tissue engineering applications is to efficiently produce as high of number of cells as it is only possible, in the shortest time. In static cultures, the production of animal cell biomass in integrated forms (i.e. aggregates, inoculated scaffolds is limited due to inefficient diffusion of culture medium components observed in such non-mixed culture systems, especially in the case of cell-inoculated fiber-based dense 3D scaffolds, inside which the intensification of mass transfer is particularly important. The applicability of a prototyped, small-scale, continuously wave-induced agitated system for intensification of anchorage-dependent CP5 chondrocytes proliferation outside and inside three-dimensional poly(lactic acid (PLA scaffolds has been discussed. Fibrous PLA-based constructs have been inoculated with CP5 cells and then maintained in two independent incubation systems: (i non-agitated conditions and (ii culture with wave-induced agitation. Significantly higher values of the volumetric glucose consumption rate have been noted for the system with the wave-induced agitation. The advantage of the presented wave-induced agitation culture system has been confirmed by lower activity of lactate dehydrogenase (LDH released from the cells in the samples of culture medium harvested from the agitated cultures, in contrast to rather high values of LDH activity measured for static conditions. Results of the proceeded experiments and their analysis clearly exhibited the feasibility of the culture system supported with continuously wave-induced agitation for robust proliferation of the CP5 chondrocytes on PLA-based structures. Aside from the practicability of the prototyped system, we believe that it could also be applied as a standard method offering advantages for all types of the daily routine laboratory-scale animal cell cultures utilizing various fiber-based biomaterials, with the use of only regular laboratory

Gene Modification of Mesenchymal Stem Cells and Articular Chondrocytes to Enhance Chondrogenesis

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Saliya Gurusinghe

2014-01-01

Full Text Available Current cell based treatment for articular cartilage and osteochondral defects are hampered by issues such as cellular dedifferentiation and hypertrophy of the resident or transplanted cells. The reduced expression of chondrogenic signalling molecules and transcription factors is a major contributing factor to changes in cell phenotype. Gene modification of chondrocytes may be one approach to redirect cells to their primary phenotype and recent advances in nonviral and viral gene delivery technologies have enabled the expression of these lost factors at high efficiency and specificity to regain chondrocyte function. This review focuses on the various candidate genes that encode signalling molecules and transcription factors that are specific for the enhancement of the chondrogenic phenotype and also how epigenetic regulators of chondrogenesis in the form of microRNA may also play an important role.

Glutaredoxin 1 (GRX1) inhibits oxidative stress and apoptosis of chondrocytes by regulating CREB/HO-1 in osteoarthritis.

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Sun, Jie; Wei, Xuelei; Lu, Yandong; Cui, Meng; Li, Fangguo; Lu, Jie; Liu, Yunjiao; Zhang, Xi

2017-10-01

GRX1 (glutaredoxin1), a sulfhydryl disulfide oxidoreductase, is involved in many cellular processes, including anti-oxidation, anti-apoptosis, and regulation of cell differentiation. However, the role of GRX1 in the oxidative stress and apoptosis of osteoarthritis chondrocytes remains unclear, prompting the current study. Protein and mRNA expressions were measured by Western blot and RT-qPCR. Oxidative stress was detected by the measurement of MDA and SOD contents. Cells apoptosis were detected by Annexin V-FITC/PI and caspase-3 activity assays. We found that the mRNA and protein expressions of GRX1 were significantly down-regulated in osteoarthritis tissues and cells. GRX1 overexpression increased the mRNA and protein expression of CREB and HO-1. Meanwhile, GRX1 overexpression inhibited oxidative stress and apoptosis in osteoarthritis chondrocytes. Furthermore, we found that GRX1 overexpression regulated HO-1 by increasing CREB, and that HO-1 regulated oxidative stress and apoptosis in osteoarthritis chondrocytes. Thus, GRX1 overexpression constrains oxidative stress and apoptosis in osteoarthritis chondrocytes by regulating CREB/HO-1, providing a novel insight into the molecular mechanism and potential treatment of osteoarthritis. Copyright © 2017. Published by Elsevier Ltd.

Substrate Stiffness Controls Osteoblastic and Chondrocytic Differentiation of Mesenchymal Stem Cells without Exogenous Stimuli.

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Rene Olivares-Navarrete

Full Text Available Stem cell fate has been linked to the mechanical properties of their underlying substrate, affecting mechanoreceptors and ultimately leading to downstream biological response. Studies have used polymers to mimic the stiffness of extracellular matrix as well as of individual tissues and shown mesenchymal stem cells (MSCs could be directed along specific lineages. In this study, we examined the role of stiffness in MSC differentiation to two closely related cell phenotypes: osteoblast and chondrocyte. We prepared four methyl acrylate/methyl methacrylate (MA/MMA polymer surfaces with elastic moduli ranging from 0.1 MPa to 310 MPa by altering monomer concentration. MSCs were cultured in media without exogenous growth factors and their biological responses were compared to committed chondrocytes and osteoblasts. Both chondrogenic and osteogenic markers were elevated when MSCs were grown on substrates with stiffness <10 MPa. Like chondrocytes, MSCs on lower stiffness substrates showed elevated expression of ACAN, SOX9, and COL2 and proteoglycan content; COMP was elevated in MSCs but reduced in chondrocytes. Substrate stiffness altered levels of RUNX2 mRNA, alkaline phosphatase specific activity, osteocalcin, and osteoprotegerin in osteoblasts, decreasing levels on the least stiff substrate. Expression of integrin subunits α1, α2, α5, αv, β1, and β3 changed in a stiffness- and cell type-dependent manner. Silencing of integrin subunit beta 1 (ITGB1 in MSCs abolished both osteoblastic and chondrogenic differentiation in response to substrate stiffness. Our results suggest that substrate stiffness is an important mediator of osteoblastic and chondrogenic differentiation, and integrin β1 plays a pivotal role in this process.

Matrix-induced autologous chondrocyte implantation for a large chondral defect in a professional football player: a case report

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Beyzadeoglu Tahsin

2012-06-01

Full Text Available Abstract Introduction Matrix-assisted autologous chondrocyte implantation is a well-known procedure for the treatment of cartilage defects, which aims to establish a regenerative milieu and restore hyaline cartilage. However, much less is known about third-generation autologous chondrocyte implantation application in high-level athletes. We report on the two-year follow-up outcome after matrix-assisted autologous chondrocyte implantation to treat a large cartilage lesion of the lateral femoral condyle in a male Caucasian professional football player. Case presentation A 27-year-old male Caucasian professional football player was previously treated for cartilage problems of his left knee with two failed microfracture procedures resulting in a 9 cm2 Outerbridge Grade 4 chondral lesion at his lateral femoral condyle. Preoperative Tegner-Lysholm and Brittberg-Peterson scores were 64 and 58, and by the second year they were 91 and 6. An evaluation with magnetic resonance imaging demonstrated filling of the defect with the signal intensity of the repair tissue resembling healthy cartilage. Second-look arthroscopy revealed robust, smooth cartilage covering his lateral femoral condyle. He returned to his former competitive level without restrictions or complaints one year after the procedure. Conclusions This case illustrates that robust cartilage tissue can be obtained with a matrix-assisted autologous chondrocyte implantation procedure even after two failed microfracture procedures in a large (9 cm2 cartilage defect. To the best of our knowledge, this is the first case report on the application of the third-generation cell therapy treatment technique, matrix-assisted autologous chondrocyte implantation, in a professional football player.

Expression Profiling and Functional Implications of a Set of Zinc Finger Proteins, ZNF423, ZNF470, ZNF521, and ZNF780B, in Primary Osteoarthritic Articular Chondrocytes

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Maria Mesuraca

2014-01-01

Full Text Available Articular chondrocytes are responsible for the maintenance of healthy articulations; indeed, dysregulation of their functions, including the production of matrix proteins and matrix-remodeling proteases, may result in fraying of the tissue and development of osteoarthritis (OA. To explore transcriptional mechanisms that contribute to the regulation of chondrocyte homeostasis and may be implicated in OA development, we compared the gene expression profile of a set of zinc finger proteins potentially linked to the control of chondrocyte differentiation and/or functions (ZNF423, ZNF470, ZNF521, and ZNF780B in chondrocytes from patients affected by OA and from subjects not affected by OA. This analysis highlighted a significantly lower expression of the transcript encoding ZNF423 in chondrocytes from OA, particularly in elderly patients. Interestingly, this decrease was mirrored by the similarly reduced expression of PPARγ, a known target of ZNF423 with anti-inflammatory and chondroprotective properties. The ZNF521 mRNA instead was abundant in all primary chondrocytes studied; the RNAi-mediated silencing of this gene significantly altered the COL2A/COL1 expression ratio, associated with the maintenance of the differentiated phenotype, in chondrocytes cultivated in alginate beads. These results suggest a role for ZNF423 and ZNF521 in the regulation of chondrocyte homeostasis and warrant further investigations to elucidate their mechanism of action.

Small-bodied humans from Palau, Micronesia.

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Lee R Berger

Full Text Available UNLABELLED: Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. BACKGROUND: Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. PRINCIPLE FINDINGS: Preliminary analysis indicates that this material is important for two reasons. First, individuals from the older time horizons are small in body size even relative to "pygmoid" populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. SIGNIFICANCE: These features may be previously unrecognized developmental correlates of small body size and, if so, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo.

Trophic effects of adipose-tissue-derived and bone-marrow-derived mesenchymal stem cells enhance cartilage generation by chondrocytes in co-culture

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Pleumeekers, M.M.; Nimeskern, L.M.; Koevoet, J. L.M.; Karperien, M.; Stok, K.S.; van Osch, G.J.V.M.

2018-01-01

Aims Combining mesenchymal stem cells (MSCs) and chondrocytes has great potential for cell-based cartilage repair. However, there is much debate regarding the mechanisms behind this concept. We aimed to clarify the mechanisms that lead to chondrogenesis (chondrocyte driven MSC-differentiation versus

Advanced oxidation protein products induce chondrocyte apoptosis via receptor for advanced glycation end products-mediated, redox-dependent intrinsic apoptosis pathway.

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Wu, Qian; Zhong, Zhao-Ming; Zhu, Si-Yuan; Liao, Cong-Rui; Pan, Ying; Zeng, Ji-Huan; Zheng, Shuai; Ding, Ruo-Ting; Lin, Qing-Song; Ye, Qing; Ye, Wen-Bin; Li, Wei; Chen, Jian-Ting

2016-01-01

Pro-inflammatory cytokine-induced chondrocyte apoptosis is a primary cause of cartilage destruction in the progression of rheumatoid arthritis (RA). Advanced oxidation protein products (AOPPs), a novel pro-inflammatory mediator, have been confirmed to accumulate in patients with RA. However, the effect of AOPPs accumulation on chondrocyte apoptosis and the associated cellular mechanisms remains unclear. The present study demonstrated that the plasma formation of AOPPs was enhanced in RA rats compared with normal. Then, chondrocyte were treated with AOPPs-modified rat serum albumin (AOPPs-RSA) in vitro. Exposure of chondrocyte to AOPPs activated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and increased expression of NADPH oxidase subunits, which was mediated by receptor for advanced glycation end products (RAGE), but not scavenger receptor CD36. Moreover, AOPPs challenge triggered NADPH oxidase-dependent ROS generation which induced mitochondrial dysfunction and endoplasmic reticulum stress resulted in activation of caspase family that eventually lead to apoptosis. Lastly, blockade of RAGE, instead of CD36, largely attenuated these signals. Our study demonstrated first time that AOPPs induce chondrocyte apoptosis via RAGE-mediated and redox-dependent intrinsic apoptosis pathway in vitro. These data implicates that AOPPs may represent a novel pathogenic factor that contributes to RA progression. Targeting AOPPs-triggered cellular mechanisms might emerge as a promising therapeutic option for patients with RA.

Demonstration of variation in chondrocyte activity in different zones of articular cartilage: an assessment of the value of in-situ hybridization.

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Marles, P J; Hoyland, J A; Parkinson, R; Freemont, A J

1991-04-01

Several methods have been described for investigating chondrocyte metabolism in vitro. In this study, in-situ hybridization (ISH) using an oligonucleotide probe (i.e. a poly-d(T) probe) to detect total messenger RNA (mRNA) in cartilage explants has been compared with radiosulphate and radioleucine uptake studies in an attempt to assess the value of ISH in investigating chondrocyte metabolism. The relative results of the three parameters indicate qualitative similarities in cells in the intermediate, deep and calcified zones but differences in the superficial zone. The relative levels of mRNA and leucine and sulphate uptake in the midzone areas could be construed as indicating that the bulk of cellular activity was directed towards the synthesis of proteoglycans. A similar relation between the three parameters, but at a lower level, was seen in chondrocytes in the calcified zone demonstrating that these cells are viable and biosynthetic. Both quantitative and qualitative differences between the three methods were observed in the superficial chondrocytes regarding the amount of mRNA compared to sulphate and leucine uptake. The results suggest that ISH can detect differences in the amount of mRNA present in chondrocytes in differing zones of cartilage and, like the radioleucine and radiosulphate studies, particularly emphasizes their functional heterogeneity.

Iterative design of peptide-based hydrogels and the effect of network electrostatics on primary chondrocyte behavior.

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Sinthuvanich, Chomdao; Haines-Butterick, Lisa A; Nagy, Katelyn J; Schneider, Joel P

2012-10-01

Iterative peptide design was used to generate two peptide-based hydrogels to study the effect of network electrostatics on primary chondrocyte behavior. MAX8 and HLT2 peptides have formal charge states of +7 and +5 per monomer, respectively. These peptides undergo triggered folding and self-assembly to afford hydrogel networks having similar rheological behavior and local network morphologies, yet different electrostatic character. Each gel can be used to directly encapsulate and syringe-deliver cells. The influence of network electrostatics on cell viability after encapsulation and delivery, extracellular matrix deposition, gene expression, and the bulk mechanical properties of the gel-cell constructs as a function of culture time was assessed. The less electropositive HLT2 gel provides a microenvironment more conducive to chondrocyte encapsulation, delivery, and phenotype maintenance. Cell viability was higher for this gel and although a moderate number of cells dedifferentiated to a fibroblast-like phenotype, many retained their chondrocytic behavior. As a result, gel-cell constructs prepared with HLT2, cultured under static in vitro conditions, contained more GAG and type II collagen resulting in mechanically superior constructs. Chondrocytes delivered in the more electropositive MAX8 gel experienced a greater degree of cell death during encapsulation and delivery and the remaining viable cells were less prone to maintain their phenotype. As a result, MAX8 gel-cell constructs had fewer cells, of which a limited number were capable of laying down cartilage-specific ECM. Published by Elsevier Ltd.

Oxygen effects on senescence in chondrocytes and mesenchymal stem cells: consequences for tissue engineering.

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Moussavi-Harami, Farid; Duwayri, Yazan; Martin, James A; Moussavi-Harami, Farshid; Buckwalter, Joseph A

2004-01-01

Primary isolates of chondrocytes and mesenchymal stem cells are often insufficient for cell-based autologous grafting procedures, necessitating in vitro expansion of cell populations. However, the potential for expansion is limited by cellular senescence, a form of irreversible cell cycle arrest regulated by intrinsic and extrinsic factors. Intrinsic mechanisms common to most somatic cells enforce senescence at the so-called "Hayflick limit" of 60 population doublings. Termed "replicative senescence", this mechanism prevents cellular immortalization and suppresses oncogenesis. Although it is possible to overcome the Hayflick limit by genetically modifying cells, such manipulations are regarded as prohibitively dangerous in the context of tissue engineering. On the other hand, senescence associated with extrinsic factors, often called "stress-induced" senescence, can be avoided simply by modifying culture conditions. Because stress-induced senescence is "premature" in the sense that it can halt growth well before the Hayflick limit is reached, growth potential can be significantly enhanced by minimizing culture related stress. Standard culture techniques were originally developed to optimize the growth of fibroblasts but these conditions are inherently stressful to many other cell types. In particular, the 21% oxygen levels used in standard incubators, though well tolerated by fibroblasts, appear to induce oxidative stress in other cells. We reasoned that chondrocytes and MSCs, which are adapted to relatively low oxygen levels in vivo, might be sensitive to this form of stress. To test this hypothesis we compared the growth of MSC and chondrocyte strains in 21% and 5% oxygen. We found that incubation in 21% oxygen significantly attenuated growth and was associated with increased oxidant production. These findings indicated that sub-optimal standard culture conditions sharply limited the expansion of MSC and chondrocyte populations and suggest that cultures for

Does Platelet-Rich Plasma Freeze-Thawing Influence Growth Factor Release and Their Effects on Chondrocytes and Synoviocytes?

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Alice Roffi

2014-01-01

Full Text Available PRP cryopreservation remains a controversial point. Our purpose was to investigate the effect of freezing/thawing on PRP molecule release, and its effects on the metabolism of chondrocytes and synoviocytes. PRP was prepared from 10 volunteers, and a half volume underwent one freezing/thawing cycle. IL-1β, HGF, PDGF AB/BB, TGF-β1, and VEGF were assayed 1 hour and 7 days after activation. Culture media of chondrocytes and synoviocytes were supplemented with fresh or frozen PRP, and, at 7 days, proliferation, gene expression, and secreted proteins levels were evaluated. Results showed that in the freeze-thawed PRP the immediate and delayed molecule releases were similar or slightly lower than those in fresh PRP. TGF-β1 and PDGF AB/BB concentrations were significantly reduced after freezing both at 1 hour and at 7 days, whereas HGF concentration was significantly lower in frozen PRP at 7 days. In fresh PRP IL-1β and HGF concentrations underwent a significant further increase after 7 days. Similar gene expression was found in chondrocytes cultured with both PRPs, whereas in synoviocytes HGF gene expression was higher in frozen PRP. PRP cryopreservation is a safe procedure, which sufficiently preserves PRP quality and its ability to induce proliferation and the production of ECM components in chondrocytes and synoviocytes.

Targeted deletion of Atg5 in chondrocytes promotes age-related osteoarthritis.

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Bouderlique, Thibault; Vuppalapati, Karuna K; Newton, Phillip T; Li, Lei; Barenius, Björn; Chagin, Andrei S

2016-03-01

It has been suggested that the lysosomal recycling process called macro-autophagy plays a role in osteoarthritis development. We thus decided to genetically ablate the autophagy-indispensable Atg5 gene specifically in chondrocytes and analyse the development of osteoarthritis upon aging and in a post-traumatic model. Mice lacking the Atg5 gene in their chondrocytes (Atg5cKO) were generated by crossing Atg5-floxed mice with transgenic mice that expressed cre recombinase driven by the collagen type 2 promoter. Animals were analysed at the age of 2, 6 and 12 months for age-related osteoarthritis or underwent mini-open partial medial meniscectomy at 2 months of age and were analysed 1 or 2 months after surgery. We evaluated osteoarthritis using the Osteoarthritis Research Society International (OARSI) scoring on safranin-O-stained samples. Cell death was evaluated by terminal deoxy-nucleotidyl-transferase-mediated deoxy-UTP nick end labelling (TUNEL) and by immunostaining of cleaved caspases. We observed the development of osteoarthritis in Atg5cKO mice with aging including fibrillation and loss of proteoglycans, which was particularly severe in males. The ablation of Atg5 was associated with an increased cell death as assessed by TUNEL, cleaved caspase 3 and cleaved caspase 9. Surprisingly, no difference in the development of post-traumatic osteoarthritis was observed between Atg5cKO and control mice. Autophagy protects from age-related osteoarthritis by facilitating chondrocyte survival. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Evc is a positive mediator of Ihh-regulated bone growth that localises at the base of chondrocyte cilia.

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Ruiz-Perez, Victor L; Blair, Helen J; Rodriguez-Andres, M Elena; Blanco, Maria Jose; Wilson, Amy; Liu, Yu-Ning; Miles, Colin; Peters, Heiko; Goodship, Judith A

2007-08-01

EVC is a novel protein mutated in the human chondroectodermal dysplasia Ellis-van Creveld syndrome (EvC; OMIM: 225500). We have inactivated Evc in the mouse and show that Evc(-/-) mice develop an EvC-like syndrome, including short ribs, short limbs and dental abnormalities. lacZ driven by the Evc promoter revealed that Evc is expressed in the developing bones and the orofacial region. Antibodies developed against Evc locate the protein at the base of the primary cilium. The growth plate of Evc(-/-) mice shows delayed bone collar formation and advanced maturation of chondrocytes. Indian hedgehog (Ihh) is expressed normally in the growth plates of Evc(-/-) mice, but expression of the Ihh downstream genes Ptch1 and Gli1 was markedly decreased. Recent studies have shown that Smo localises to primary cilia and that Gli3 processing is defective in intraflagellar transport mutants. In vitro studies using Evc(-/-) cells demonstrate that the defect lies downstream of Smo. Chondrocyte cilia are present in Evc(-/-) mice and Gli3 processing appears normal by western blot analysis. We conclude that Evc is an intracellular component of the hedgehog signal transduction pathway that is required for normal transcriptional activation of Ihh target genes.

A cell shrinkage artefact in growth plate chondrocytes with common fixative solutions: importance of fixative osmolarity for maintaining morphology

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MY Loqman

2010-05-01

Full Text Available The remarkable increase in chondrocyte volume is a major determinant in the longitudinal growth of mammalian bones. To permit a detailed morphological study of hypertrophic chondrocytes using standard histological techniques, the preservation of normal chondrocyte morphology is essential. We noticed that during fixation of growth plates with conventional fixative solutions, there was a marked morphological (shrinkage artifact, and we postulated that this arose from the hyper-osmotic nature of these solutions. To test this, we fixed proximal tibia growth plates of 7-day-old rat bones in either (a paraformaldehyde (PFA; 4%, (b glutaraldehyde (GA; 2% with PFA (2% with ruthenium hexamine trichloride (RHT; 0.7%, (c GA (2% with RHT (0.7%, or (d GA (1.3% with RHT (0.5% and osmolarity adjusted to a ‘physiological’ level of ~280mOsm. Using conventional histological methods, confocal microscopy, and image analysis on fluorescently-labelled fixed and living chondrocytes, we then quantified the extent of cell shrinkage and volume change. Our data showed that the high osmolarity of conventional fixatives caused a shrinkage artefact to chondrocytes. This was particularly evident when whole bones were fixed, but could be markedly reduced if bones were sagittally bisected prior to fixation. The shrinkage artefact could be avoided by adjusting the osmolarity of the fixatives to the osmotic pressure of normal extracellular fluids (~280mOsm. These results emphasize the importance of fixative osmolarity, in order to accurately preserve the normal volume/morphology of cells within tissues.

Deletion of IFT80 Impairs Epiphyseal and Articular Cartilage Formation Due to Disruption of Chondrocyte Differentiation

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Yuan, Xue; Yang, Shuying

2015-01-01

Intraflagellar transport proteins (IFT) play important roles in cilia formation and organ development. Partial loss of IFT80 function leads Jeune asphyxiating thoracic dystrophy (JATD) or short-rib polydactyly (SRP) syndrome type III, displaying narrow thoracic cavity and multiple cartilage anomalies. However, it is unknown how IFT80 regulates cartilage formation. To define the role and mechanism of IFT80 in chondrocyte function and cartilage formation, we generated a Col2α1; IFT80f/f mouse model by crossing IFT80f/f mice with inducible Col2α1-CreER mice, and deleted IFT80 in chondrocyte lineage by injection of tamoxifen into the mice in embryonic or postnatal stage. Loss of IFT80 in the embryonic stage resulted in short limbs at birth. Histological studies showed that IFT80-deficient mice have shortened cartilage with marked changes in cellular morphology and organization in the resting, proliferative, pre-hypertrophic, and hypertrophic zones. Moreover, deletion of IFT80 in the postnatal stage led to mouse stunted growth with shortened growth plate but thickened articular cartilage. Defects of ciliogenesis were found in the cartilage of IFT80-deficient mice and primary IFT80-deficient chondrocytes. Further study showed that chondrogenic differentiation was significantly inhibited in IFT80-deficient mice due to reduced hedgehog (Hh) signaling and increased Wnt signaling activities. These findings demonstrate that loss of IFT80 blocks chondrocyte differentiation by disruption of ciliogenesis and alteration of Hh and Wnt signaling transduction, which in turn alters epiphyseal and articular cartilage formation. PMID:26098911

IGF-1R signaling in chondrocytes modulates growth plate development by interacting with the PTHrP/Ihh pathway.

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Wang, Yongmei; Cheng, Zhiqiang; Elalieh, Hashem Z; Nakamura, Eiichiro; Nguyen, Minh-Thanh; Mackem, Susan; Clemens, Thomas L; Bikle, Daniel D; Chang, Wenhan

2011-07-01

Systemic derangements and perinatal death of generalized insulin-like growth factor 1 (IGF-1) and IGF-1 receptor (IGF-1R) knockout mice preclude definitive assessment of IGF-1R actions in growth-plate (GP) chondrocytes. We generated cartilage-specific Igf1r knockout ((Cart) Igf1r(-/-)) mice to investigate local control of chondrocyte differentiation in the GP by this receptor. These mice died shortly after birth and showed disorganized chondrocyte columns, delayed ossification and vascular invasion, decreased cell proliferation, increased apoptosis, and increased expression of parathyroid hormone-related protein (Pthrp) RNA and protein in their GPs. The increased Pthrp expression in the knockout GPs likely was due to an increase in gene transcription, as determined by the increased activity of a LacZ reporter that was inserted downstream of the endogenous PTHrP promoter and bred into the knockout mice. To circumvent the early death of (Cart) Igf1r(-/-) mice and investigate the role of IGF-1R during postnatal growth, we made tamoxifen (Tam)-inducible, cartilage-specific Igf1r knockout ((TamCart) Igf1r(-/-)) mice. At 2 weeks of age and 7 to 8 days after Tam injection, the (TamCart) Igf1r(-/-) mice showed growth retardation with a disorganized GP, reduced chondrocyte proliferation, decreased type 2 collagen and Indian Hedgehog (Ihh) expression, but increased expression of PTHrP. Consistent with in vivo observations, in vitro knockout of the Igf1r gene by adenoviral expression of Cre recombinase suppressed cell proliferation, promoted apoptosis, and increased Pthrp expression. Our data indicate that the IGF-1R in chondrocytes controls cell growth, survival, and differentiation in embryonic and postnatal GPs in part by suppression of Pthrp expression. Copyright © 2011 American Society for Bone and Mineral Research.

Reciprocal regulation by hypoxia-inducible factor-2α and the NAMPT-NAD(+)-SIRT axis in articular chondrocytes is involved in osteoarthritis.

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Oh, H; Kwak, J-S; Yang, S; Gong, M-K; Kim, J-H; Rhee, J; Kim, S K; Kim, H-E; Ryu, J-H; Chun, J-S

2015-12-01

Hypoxia-inducible factor-2α (HIF-2α) transcriptionally upregulates Nampt in articular chondrocytes. NAMPT, which exhibits nicotinamide phosphoribosyltransferase activity, in turn causes osteoarthritis (OA) in mice by stimulating the expression of matrix-degrading enzymes. Here, we sought to elucidate whether HIF-2α activates the NAMPT-NAD(+)-SIRT axis in chondrocytes and thereby contributes to the pathogenesis of OA. Assays of NAD levels, SIRT activity, reporter gene activity, mRNA, and protein levels were conducted in primary cultured mouse articular chondrocytes. Experimental OA in mice was induced by intra-articular (IA) injection of adenovirus expressing HIF-2α (Ad-Epas1) or NAMPT (Ad-Nampt). The functions of SIRT in OA were examined by IA co-injection of SIRT inhibitors or adenovirus expressing individual SIRT isoforms or shRNA targeting specific SIRT isoforms. HIF-2α activated the NAMPT-NAD(+)-SIRT axis in chondrocytes by upregulating NAMPT, which stimulated NAD(+) synthesis and thereby activated SIRT family members. The activated NAMPT-SIRT pathway, in turn, promoted HIF-2α protein stability by negatively regulating its hydroxylation and 26S proteasome-mediated degradation, resulting in increased HIF-2α transcriptional activity. Among SIRT family members (SIRT1-7), SIRT2 and SIRT4 were positively associated with HIF-2α stability and transcriptional activity in chondrocytes. This reciprocal regulation was required for the expression of catabolic matrix metalloproteinases (MMP3, MMP12, and MMP13) and OA cartilage destruction caused by IA injection of Ad-Epas1 Ad-Nampt. The reciprocal regulation of HIF-2α and the NAMPT-NAD(+)-SIRT axis in articular chondrocytes is involved in OA cartilage destruction caused by HIF-2α or NAMPT. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Hydrostatic Compress Force Enhances the Viability and Decreases the Apoptosis of Condylar Chondrocytes through Integrin-FAK-ERK/PI3K Pathway

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Ma, Dandan; Kou, Xiaoxing; Jin, Jing; Xu, Taotao; Wu, Mengjie; Deng, Liquan; Fu, Lusi; Liu, Yi; Wu, Gang; Lu, Haiping

2016-01-01

Reduced mechanical stimuli in many pathological cases, such as hemimastication and limited masticatory movements, can significantly affect the metabolic activity of mandibular condylar chondrocytes and the growth of mandibles. However, the molecular mechanisms for these phenomena remain unclear. In this study, we hypothesized that integrin-focal adhesion kinase (FAK)-ERK (extracellular signal–regulated kinase)/PI3K (phosphatidylinositol-3-kinase) signaling pathway mediated the cellular response of condylar chondrocytes to mechanical loading. Primary condylar chondrocytes were exposed to hydrostatic compressive forces (HCFs) of different magnitudes (0, 50, 100, 150, 200, and 250 kPa) for 2 h. We measured the viability, morphology, and apoptosis of the chondrocytes with different treatments as well as the gene, protein expression, and phosphorylation of mechanosensitivity-related molecules, such as integrin α2, integrin α5, integrin β1, FAK, ERK, and PI3K. HCFs could significantly increase the viability and surface area of condylar chondrocytes and decrease their apoptosis in a dose-dependent manner. HCF of 250 kPa resulted in a 1.51 ± 0.02-fold increase of cell viability and reduced the ratio of apoptotic cells from 18.10% ± 0.56% to 7.30% ± 1.43%. HCFs could significantly enhance the mRNA and protein expression of integrin α2, integrin α5, and integrin β1 in a dose-dependent manner, but not ERK1, ERK2, or PI3K. Instead, HCF could significantly increase phosphorylation levels of FAK, ERK1/2, and PI3K in a dose-dependent manner. Cilengitide, the potent integrin inhibitor, could dose-dependently block such effects of HCFs. HCFs enhances the viability and decreases the apoptosis of condylar chondrocytes through the integrin-FAK-ERK/PI3K pathway. PMID:27827993

Expression and Immunohistochemical Localisation of the G beta gamma activated and Calcineurin-inhibited Adenylyl Cyclase Isoforms in Rat Articular Chondrocytes

International Nuclear Information System (INIS)

Memon, I.; Khan, K.M.; Siddiqui, S.; Perveen, S.; Ishaq, M.

2016-01-01

Objective: To determine the expression and localisation of the Gβγ-activated adenylyl cyclase (AC) isoforms 2, 4, and 7 and calcineurin-inhibited AC isoform 9 in rat articular chondrocytes. Study Design: Experimental study. Place and Duration of Study: Jumma Research Laboratory and Histology Laboratory, The Aga Khan University, Karachi, from 2009 to 2011. Methodology: Fresh slices of articular cartilage were taken from various synovial joints of rats of different age groups. The expression of AC isoforms was determined by RT-PCR and immunohistochemistry was performed to localise these isoforms in articular chondrocytes. Tissue sections were processed for immunostaining with respective antibodies. The color was developed by diaminobenzidine. Results: All the studied AC isoforms were found to be differentially expressed in different zones of the rat articular cartilage. Generally, expression of all AC isoforms studied increased with age. The expression of the AC isoforms through PCR was almost consistent with the localisation of these isoforms by immunohistochemistry. Conclusion: These data add to the information about signalling cascades possibly involved in articular chondrocytes. Variable expression of AC isoforms 2, 4, 7, and 9 suggest a role for the signalling cascades regulated by the AC isoforms in articular chondrocytes. (author)

Chondrogenesis of human adipose derived stem cells for future microtia repair using co-culture technique.

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Goh, Bee See; Che Omar, Siti Nurhadis; Ubaidah, Muhammad Azhan; Saim, Lokman; Sulaiman, Shamsul; Chua, Kien Hui

2017-04-01

In conclusion, these result showed HADSCs could differentiate into chondrocytes-like cells, dependent on signaling induced by TGF-β3 and chondrocytes. This is a promising result and showed that HADSCs is a potential source for future microtia repair. The technique of co-culture is a positive way forward to assist the microtia tissue. Reconstructive surgery for the repair of microtia still remains the greatest challenge among the surgeons. Its repair is associated with donor-site morbidity and the degree of infection is inevitable when using alloplastic prosthesis with uncertain long-term durability. Thus, human adipose derived stem cells (HADSCs) can be an alternative cell source for cartilage regeneration. This study aims to evaluate the chondrogenic potential of HADSCs cultured with transforming growth factor-beta (TGF-β) and interaction of auricular chondrocytes with HADSCs for new cartilage generation. Multi-lineages differentiation features of HADSCs were monitored by Alcian Blue, Alizarin Red, and Oil Red O staining for chondrogenic, adipogenic, and osteogenic differentiation capacity, respectively. Further, HADSCs alone were culture in medium added with TGF-β3; and human auricular chondrocytes were interacted indirectly in the culture with and without TGF-βs for up to 21 days, respectively. Cell morphology and chondrogenesis were monitored by inverted microscope. For cell viability, Alamar Blue assay was used to measure the cell viability and the changes in gene expression of auricular chondrocyte markers were determined by real-time polymerase chain reaction analysis. For the induction of chondrogenic differentiation, HADSCs showed a feature of aggregation and formed a dense matrix of proteoglycans. Staining results from Alizirin Red and Oil Red O indicated the HADSCs also successfully differentiated into adipogenic and osteogenic lineages after 21 days. According to a previous study, HADSCs were strongly positive for the mesenchymal markers CD90, CD73

Sorbitol-modified hyaluronic acid reduces oxidative stress, apoptosis and mediators of inflammation and catabolism in human osteoarthritic chondrocytes.

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Mongkhon, John-Max; Thach, Maryane; Shi, Qin; Fernandes, Julio C; Fahmi, Hassan; Benderdour, Mohamed

2014-08-01

Our study was designed to elucidate the precise molecular mechanisms by which sorbitol-modified hyaluronic acid (HA/sorbitol) exerts beneficial effects in osteoarthritis (OA). Human OA chondrocytes were treated with increasing doses of HA/sorbitol ± anti-CD44 antibody or with sorbitol alone and thereafter with or without interleukin-1beta (IL-1β) or hydrogen peroxide (H2O2). Signal transduction pathways and parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. HA/sorbitol prevented IL-1β-induced oxidative stress, as measured by reactive oxygen species, p47-NADPH oxidase phosphorylation, 4-hydroxynonenal (HNE) production and HNE-metabolizing glutathione-S-transferase A4-4 expression. Moreover, HA/sorbitol stifled IL-1β-induced metalloproteinase-13, nitric oxide (NO) and prostaglandin E2 release as well as inducible NO synthase expression. Study of the apoptosis process revealed that this gel significantly attenuated cell death, caspase-3 activation and DNA fragmentation elicited by exposure to a cytotoxic H2O2 dose. Examination of signaling pathway components disclosed that HA/sorbitol prevented IL-1β-induced p38 mitogen-activated protein kinase and nuclear factor-kappa B activation, but not that of extracellular signal-regulated kinases 1 and 2. Interestingly, the antioxidant as well as the anti-inflammatory and anti-catabolic effects of HA/sorbitol were attributed to sorbitol and HA, respectively. Altogether, our findings support a beneficial effect of HA/sorbitol in OA through the restoration of redox status and reduction of apoptosis, inflammation and catabolism involved in cartilage damage.

Synoviocytes, not chondrocytes, release free radicals after cycles of anoxia/re-oxygenation

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Schneider, Nicole; Mouithys-Mickalad, Ange L.; Lejeune, Jean-Philippe; Deby-Dupont, Ginette P.; Hoebeke, Maryse; Serteyn, Didier A.

2005-01-01

By oxymetry and electron paramagnetic resonance (EPR), we investigated the effects of repeated anoxia/re-oxygenation (A/R) periods on the respiration and production of free radicals by synoviocytes (rabbit HIG-82 cell line and primary equine synoviocytes) and equine articular chondrocytes. Three periods of 20 min anoxia followed by re-oxygenation were applied to 10 7 cells; O 2 consumption was measured before anoxia and after each re-oxygenation. After the last A/R, cellular free radical formation was investigated by EPR spectroscopy with spin trapping technique (n = 3 for each cell line). Both types of synoviocytes showed a high O 2 consumption, which was slowered after anoxia. By EPR with the spin trap POBN, we proved a free radical formation. Results were similar for equine and rabbit synoviocytes. For chondrocytes, we observed a low O 2 consumption, unchanged by anoxia, and no free radical production. These observations suggest an oxidant activity of synoviocytes, potentially important for the onset of osteoarthritis

Epiphyseal abnormalities, trabecular bone loss and articular chondrocyte hypertrophy develop in the long bones of postnatal Ext1-deficient mice.

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Sgariglia, Federica; Candela, Maria Elena; Huegel, Julianne; Jacenko, Olena; Koyama, Eiki; Yamaguchi, Yu; Pacifici, Maurizio; Enomoto-Iwamoto, Motomi

2013-11-01

Long bones are integral components of the limb skeleton. Recent studies have indicated that embryonic long bone development is altered by mutations in Ext genes and consequent heparan sulfate (HS) deficiency, possibly due to changes in activity and distribution of HS-binding/growth plate-associated signaling proteins. Here we asked whether Ext function is continuously required after birth to sustain growth plate function and long bone growth and organization. Compound transgenic Ext1(f/f);Col2CreERT mice were injected with tamoxifen at postnatal day 5 (P5) to ablate Ext1 in cartilage and monitored over time. The Ext1-deficient mice exhibited growth retardation already by 2weeks post-injection, as did their long bones. Mutant growth plates displayed a severe disorganization of chondrocyte columnar organization, a shortened hypertrophic zone with low expression of collagen X and MMP-13, and reduced primary spongiosa accompanied, however, by increased numbers of TRAP-positive osteoclasts at the chondro-osseous border. The mutant epiphyses were abnormal as well. Formation of a secondary ossification center was significantly delayed but interestingly, hypertrophic-like chondrocytes emerged within articular cartilage, similar to those often seen in osteoarthritic joints. Indeed, the cells displayed a large size and round shape, expressed collagen X and MMP-13 and were surrounded by an abundant Perlecan-rich pericellular matrix not seen in control articular chondrocytes. In addition, ectopic cartilaginous outgrowths developed on the lateral side of mutant growth plates over time that resembled exostotic characteristic of children with Hereditary Multiple Exostoses, a syndrome caused by Ext mutations and HS deficiency. In sum, the data do show that Ext1 is continuously required for postnatal growth and organization of long bones as well as their adjacent joints. Ext1 deficiency elicits defects that can occur in human skeletal conditions including trabecular bone loss

Intralesional Osteophyte Regrowth Following Autologous Chondrocyte Implantation after Previous Treatment with Marrow Stimulation Technique.

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Demange, Marco Kawamura; Minas, Tom; von Keudell, Arvind; Sodha, Sonal; Bryant, Tim; Gomoll, Andreas H

2017-04-01

Objective Bone marrow stimulation surgeries are frequent in the treatment of cartilage lesions. Autologous chondrocyte implantation (ACI) may be performed after failed microfracture surgery. Alterations to subchondral bone as intralesional osteophytes are commonly seen after previous microfracture and removed during ACI. There have been no reports on potential recurrence. Our purpose was to evaluate the incidence of intralesional osteophyte development in 2 cohorts: existing intralesional osteophytes and without intralesional osteophytes at the time of ACI. Study Design We identified 87 patients (157 lesions) with intralesional osteophytes among a cohort of 497 ACI patients. Osteophyte regrowth was analyzed on magnetic resonance imaging and categorized as small or large (less or more than 50% of the cartilage thickness). Twenty patients (24 defects) without intralesional osteophytes at the time of ACI acted as control. Results Osteophyte regrowth was observed in 39.5% of lesions (34.4% of small osteophytes and 5.1% of large osteophytes). In subgroup analyses, regrowth was observed in 45.8% of periosteal-covered defects and in 18.9% of collagen membrane-covered defects. Large osteophyte regrowth occurred in less than 5% in either group. Periosteal defects showed a significantly higher incidence for regrowth of small osteophytes. In the control group, intralesional osteophytes developed in 16.7% of the lesions. Conclusions Even though intralesional osteophytes may regrow after removal during ACI, most of them are small. Small osteophyte regrowth occurs almost twice in periosteum-covered ACI. Large osteophytes occur only in 5% of patients. Intralesional osteophyte formation is not significantly different in preexisting intralesional osteophytes and control groups.

Autophagy Is a Protective Response to the Oxidative Damage to Endplate Chondrocytes in Intervertebral Disc: Implications for the Treatment of Degenerative Lumbar Disc

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Ke Chen

2017-01-01

Full Text Available Low back pain (LBP is the leading cause of disability in the elderly. Intervertebral disc degeneration (IDD was considered as the main cause for LBP. Degeneration of cartilaginous endplate was a crucial harmful factor during the initiation and development of IDD. Oxidative stress was implicated in IDD. However, the underlying molecular mechanism for the degeneration of cartilaginous endplate remains elusive. Herein, we found that oxidative stress could induce apoptosis and autophagy in endplate chondrocytes evidenced by western blot analysis, flow cytometry, immunofluorescence staining, GFP-LC3B transfection, and MDC staining. In addition, we also found that the apoptosis of endplate chondrocytes was significantly increased after the inhibition of autophagy by bafilomycin A1 shown by flow cytometry. Furthermore, mTOR pathway upstream autophagy was greatly suppressed suggested by western blot assay. In conclusion, our study strongly revealed that oxidative stress could increase autophagy and apoptosis of endplate chondrocytes in intervertebral disc. The increase of autophagy activity could prevent endplate chondrocytes from apoptosis. The autophagy in endplate chondrocytes induced by oxidative stress was mTOR dependent. These findings might shed some new lights on the mechanism for IDD and provide new strategies for the treatments of IDD.

ATX-LPA1 axis contributes to proliferation of chondrocytes by regulating fibronectin assembly leading to proper cartilage formation.

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Nishioka, Tatsuji; Arima, Naoaki; Kano, Kuniyuki; Hama, Kotaro; Itai, Eriko; Yukiura, Hiroshi; Kise, Ryoji; Inoue, Asuka; Kim, Seok-Hyung; Solnica-Krezel, Lilianna; Moolenaar, Wouter H; Chun, Jerold; Aoki, Junken

2016-03-23

The lipid mediator lysophosphatidic acid (LPA) signals via six distinct G protein-coupled receptors to mediate both unique and overlapping biological effects, including cell migration, proliferation and survival. LPA is produced extracellularly by autotaxin (ATX), a secreted lysophospholipase D, from lysophosphatidylcholine. ATX-LPA receptor signaling is essential for normal development and implicated in various (patho)physiological processes, but underlying mechanisms remain incompletely understood. Through gene targeting approaches in zebrafish and mice, we show here that loss of ATX-LPA1 signaling leads to disorganization of chondrocytes, causing severe defects in cartilage formation. Mechanistically, ATX-LPA1 signaling acts by promoting S-phase entry and cell proliferation of chondrocytes both in vitro and in vivo, at least in part through β1-integrin translocation leading to fibronectin assembly and further extracellular matrix deposition; this in turn promotes chondrocyte-matrix adhesion and cell proliferation. Thus, the ATX-LPA1 axis is a key regulator of cartilage formation.

One-stage focal cartilage defect treatment with bone marrow mononuclear cells and chondrocytes leads to better macroscopic cartilage regeneration compared to microfracture in goats

NARCIS (Netherlands)

Bekkers, J.E.J.; Creemers, L.B.; Tsuchida, A.I.; van Rijen, M.H.P.; Custers, R.J.H.; Dhert, W.J.A.; Saris, Daniël B.F.

2013-01-01

Objective The combination of chondrocytes and mononuclear fraction (MNF) cells might solve the expansion induced dedifferentiation problem of reimplanted cells in autologous chondrocytes implantation as sufficient cells would be available for direct, one-stage, implantation. Earlier in vitro work

A novel transgenic mouse model of growth plate dysplasia reveals that decreased chondrocyte proliferation due to chronic ER stress is a key factor in reduced bone growth

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Benedetta Gualeni

2013-11-01

Disease mechanisms leading to different forms of chondrodysplasia include extracellular matrix (ECM alterations and intracellular stress resulting in abnormal changes to chondrocyte proliferation and survival. Delineating the relative contribution of these two disease mechanisms is a major challenge in understanding disease pathophysiology in genetic skeletal diseases and a prerequisite for developing effective therapies. To determine the influence of intracellular stress and changes in chondrocyte phenotype to the development of chondrodysplasia, we targeted the expression of the G2320R mutant form of thyroglobulin to the endoplasmic reticulum (ER of resting and proliferating chondrocytes. Previous studies on this mutant protein have shown that it induces intracellular aggregates and causes cell stress and death in the thyroid gland. The expression and retention of this exogenous mutant protein in resting and proliferating chondrocytes resulted in a chronic cell stress response, growth plate dysplasia and reduced bone growth, without inducing any alterations to the architecture and organization of the cartilage ECM. More significantly, the decreased bone growth seemed to be the direct result of reduced chondrocyte proliferation in the proliferative zone of growth plates in transgenic mice, without transcriptional activation of a classical unfolded protein response (UPR or apoptosis. Overall, these data show that mutant protein retention in the ER of resting and proliferative zone chondrocytes is sufficient to cause disrupted bone growth. The specific disease pathways triggered by mutant protein retention do not necessarily involve a prototypic UPR, but all pathways impact upon chondrocyte proliferation in the cartilage growth plate.

Characteristic complications after autologous chondrocyte implantation for cartilage defects of the knee joint

DEFF Research Database (Denmark)

Niemeyer, Philipp; Pestka, Jan M; Kreuz, Peter C

2008-01-01

BACKGROUND: Although autologous chondrocyte implantation (ACI) is a well-established therapy for the treatment of isolated cartilage defects of the knee joint, little is known about typical complications and their treatment after ACI. HYPOTHESIS: Unsatisfactory outcome after ACI is associated...

Small-world human brain networks: Perspectives and challenges.

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Liao, Xuhong; Vasilakos, Athanasios V; He, Yong

2017-06-01

Modelling the human brain as a complex network has provided a powerful mathematical framework to characterize the structural and functional architectures of the brain. In the past decade, the combination of non-invasive neuroimaging techniques and graph theoretical approaches enable us to map human structural and functional connectivity patterns (i.e., connectome) at the macroscopic level. One of the most influential findings is that human brain networks exhibit prominent small-world organization. Such a network architecture in the human brain facilitates efficient information segregation and integration at low wiring and energy costs, which presumably results from natural selection under the pressure of a cost-efficiency balance. Moreover, the small-world organization undergoes continuous changes during normal development and ageing and exhibits dramatic alterations in neurological and psychiatric disorders. In this review, we survey recent advances regarding the small-world architecture in human brain networks and highlight the potential implications and applications in multidisciplinary fields, including cognitive neuroscience, medicine and engineering. Finally, we highlight several challenging issues and areas for future research in this rapidly growing field. Copyright © 2017 Elsevier Ltd. All rights reserved.

Integration of Stem Cell to Chondrocyte-Derived Cartilage Matrix in Healthy and Osteoarthritic States in the Presence of Hydroxyapatite Nanoparticles.

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Rupak Dua

Full Text Available We investigated the effectiveness of integrating tissue engineered cartilage derived from human bone marrow derived stem cells (HBMSCs to healthy as well as osteoarthritic cartilage mimics using hydroxyapatite (HA nanoparticles immersed within a hydrogel substrate. Healthy and diseased engineered cartilage from human chondrocytes (cultured in agar gels were integrated with human bone marrow stem cell (HBMSC-derived cartilaginous engineered matrix with and without HA, and evaluated after 28 days of growth. HBMSCs were seeded within photopolymerizable poly (ethylene glycol diacrylate (PEGDA hydrogels. In addition, we also conducted a preliminary in vivo evaluation of cartilage repair in rabbit knee chondral defects treated with subchondral bone microfracture and cell-free PEGDA with and without HA. Under in vitro conditions, the interfacial shear strength between tissue engineered cartilage derived from HBMSCs and osteoarthritic chondrocytes was significantly higher (p < 0.05 when HA nanoparticles were incorporated within the HBMSC culture system. Histological evidence confirmed a distinct spatial transition zone, rich in calcium phosphate deposits. Assessment of explanted rabbit knees by histology demonstrated that cellularity within the repair tissues that had filled the defects were of significantly higher number (p < 0.05 when HA was used. HA nanoparticles play an important role in treating chondral defects when osteoarthritis is a co-morbidity. We speculate that the calcified layer formation at the interface in the osteoarthritic environment in the presence of HA is likely to have attributed to higher interfacial strength found in vitro. From an in vivo standpoint, the presence of HA promoted cellularity in the tissues that subsequently filled the chondral defects. This higher presence of cells can be considered important in the context of accelerating long-term cartilage remodeling. We conclude that HA nanoparticles play an important role in

The role of MCP-1-CCR2 ligand-receptor axis in chondrocyte degradation and disease progress in knee osteoarthritis

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Yuan-kun Xu

Full Text Available BACKGROUND: Osteoarthritis (OA is a common arthritic disease and multifactorial whole-joint disease. Interactions of chemokines and OA is inadequately documented RESULTS: In vivo and in vitro studies were conducted to investigate monocyte chemoattractant protein 1 (MCP-1 and receptor chemokine (C-C motif receptor 2 (CCR2 in chondrocyte degradation and cartilage degeneration. Chondrocytes from 16 OA patients and 6 normal controls were involved in this study. After stimulation of MCP-1, the expression of MCP-1 and CCR2 increased significantly (P < 0.001 and the expression of MMP-13 also increased (P < 0.05. MCP-1 stimulation also induced (or enhanced the apoptosis of OA chondrocytes (P < 0.05. Additionally, the degradation of cartilage matrix markers (metalloproteinase 3 and 13, MMP3 and MMP13 in the culture medium of normal chondrocytes was also assessed. Furthermore, intra-articular injection of MCP-1 in mouse knees induced cartilage degradation and the CCR2 antagonist did not impede cartilage destroy in rats knees of monosodium iodoacetate (MIA model CONCLUSIONS: The results of this study demonstrate that the MCP-1-CCR2 ligand-receptor axis plays a special role in the initiation and progression of OA pathology. Patients with ambiguous etiology can gain some insight from the MCP-1-CCR2 ligand-receptor axis

The Study of the Frequency Effect of Dynamic Compressive Loading on Primary Articular Chondrocyte Functions Using a Microcell Culture System

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Wan-Ying Lin

2014-01-01

Full Text Available Compressive stimulation can modulate articular chondrocyte functions. Nevertheless, the relevant studies are not comprehensive. This is primarily due to the lack of cell culture apparatuses capable of conducting the experiments in a high throughput, precise, and cost-effective manner. To address the issue, we demonstrated the use of a perfusion microcell culture system to investigate the stimulating frequency (0.5, 1.0, and 2.0 Hz effect of compressive loading (20% and 40% strain on the functions of articular chondrocytes. The system mainly integrates the functions of continuous culture medium perfusion and the generation of pneumatically-driven compressive stimulation in a high-throughput micro cell culture system. Results showed that the compressive stimulations explored did not have a significant impact on chondrocyte viability and proliferation. However, the metabolic activity of chondrocytes was significantly affected by the stimulating frequency at the higher compressive strain of 40% (2 Hz, 40% strain. Under the two compressive strains studied, the glycosaminoglycans (GAGs synthesis was upregulated when the stimulating frequency was set at 1 Hz and 2 Hz. However, the stimulating frequencies explored had no influence on the collagen production. The results of this study provide useful fundamental insights that will be helpful for cartilage tissue engineering and cartilage rehabilitation.

Hidden layers of human small RNAs

DEFF Research Database (Denmark)

Kawaji, Hideya; Nakamura, Mari; Takahashi, Yukari

2008-01-01

small RNA have focused on miRNA and/or siRNA rather than on the exploration of additional classes of RNAs. RESULTS: Here, we explored human small RNAs by unbiased sequencing of RNAs with sizes of 19-40 nt. We provide substantial evidences for the existence of independent classes of small RNAs. Our data......BACKGROUND: Small RNA attracts increasing interest based on the discovery of RNA silencing and the rapid progress of our understanding of these phenomena. Although recent studies suggest the possible existence of yet undiscovered types of small RNAs in higher organisms, many studies to profile...... shows that well-characterized non-coding RNA, such as tRNA, snoRNA, and snRNA are cleaved at sites specific to the class of ncRNA. In particular, tRNA cleavage is regulated depending on tRNA type and tissue expression. We also found small RNAs mapped to genomic regions that are transcribed in both...

Autologous chondrocyte implantation for cartilage injury treatment in Chiang Mai University Hospital: a case report.

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Wongtriratanachai, Prasit; Pruksakorn, Dumnoensun; Pothacharoen, Peraphan; Nimkingratana, Puwapong; Pattamapaspong, Nuttaya; Phornphutkul, Chanakarn; Setsitthakun, Sasiwariya; Fongsatitkul, Ladda; Phrompaet, Sureeporn

2013-11-01

Autologous chondrocyte implantation (ACI) has become one of the standard procedures for articular cartilage defect treatment. This technique provides a promising result. However the procedural process requires an approach of several steps from multidisciplinary teams. Although the success of this procedure has been reported from Srinakharinvirot University since 2007, the application of ACI is still limited in Thailand due to the complexity of processes and stringent quality control. This report is to present the first case of the cartilage defect treatment using the first generation-ACI under Chiang Mai University's (CMU) own facility and Ethics Committee. This paper also reviews the process of biotechnology procedures, patient selection, surgical, and rehabilitation techniques. The success of the first case is an important milestone for the further development of the CMU Human Translational Research Laboratory in near future.

Emerging Players at the Intersection of Chondrocyte Loss of Maturational Arrest, Oxidative Stress, Senescence and Low-Grade Inflammation in Osteoarthritis

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Manuela Minguzzi

2018-01-01

Full Text Available The prevalence of Osteoarthritis (OA is increasing because of the progressive aging and unhealthy lifestyle. These risk factors trigger OA by removing constraints that keep the tightly regulated low turnover of the extracellular matrix (ECM of articular cartilage, the correct chondrocyte phenotype, and the functionality of major homeostatic mechanisms, such as mitophagy, that allows for the clearance of dysfunctional mitochondria, preventing increased production of reactive oxygen species, oxidative stress, and senescence. After OA onset, the presence of ECM degradation products is perceived as a “danger” signal by the chondrocytes and the synovial macrophages that release alarmins with autocrine/paracrine effects on the same cells. Alarmins trigger innate immunity in the joint, with important systemic crosstalks that explain the beneficial effects of dietary interventions and improved lifestyle. Alarmins also boost low-grade inflammation: the release of inflammatory molecules and chemokines sustained by continuous triggering of NF-κB within an altered cellular setting that allows its higher transcriptional activity. Chemokines exert pleiotropic functions in OA, including the recruitment of inflammatory cells and the induction of ECM remodeling. Some chemokines have been successfully targeted to attenuate structural damage or pain in OA animal models. This represents a promising strategy for the future management of human OA.

Emerging Players at the Intersection of Chondrocyte Loss of Maturational Arrest, Oxidative Stress, Senescence and Low-Grade Inflammation in Osteoarthritis.

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Minguzzi, Manuela; Cetrullo, Silvia; D'Adamo, Stefania; Silvestri, Ylenia; Flamigni, Flavio; Borzì, Rosa Maria

2018-01-01

The prevalence of Osteoarthritis (OA) is increasing because of the progressive aging and unhealthy lifestyle. These risk factors trigger OA by removing constraints that keep the tightly regulated low turnover of the extracellular matrix (ECM) of articular cartilage, the correct chondrocyte phenotype, and the functionality of major homeostatic mechanisms, such as mitophagy, that allows for the clearance of dysfunctional mitochondria, preventing increased production of reactive oxygen species, oxidative stress, and senescence. After OA onset, the presence of ECM degradation products is perceived as a "danger" signal by the chondrocytes and the synovial macrophages that release alarmins with autocrine/paracrine effects on the same cells. Alarmins trigger innate immunity in the joint, with important systemic crosstalks that explain the beneficial effects of dietary interventions and improved lifestyle. Alarmins also boost low-grade inflammation: the release of inflammatory molecules and chemokines sustained by continuous triggering of NF- κ B within an altered cellular setting that allows its higher transcriptional activity. Chemokines exert pleiotropic functions in OA, including the recruitment of inflammatory cells and the induction of ECM remodeling. Some chemokines have been successfully targeted to attenuate structural damage or pain in OA animal models. This represents a promising strategy for the future management of human OA.

Retinoic acid, hemin and hexamethylen bisacetamide interference with "in vitro" differentiation of chick embryo chondrocytes.

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Manduca, P; Abelmoschi, M L

1992-01-01

We have investigated the effect of all-trans Retinoic acid, and of substances (Hemine and Hexamethylene bisacetamide) which interfere with "in vitro" differentiation of mesenchyme derived cell lineages on the expression of specific markers of hyperthrophy in "in vitro" differentiating chick embryo chondrocytes. (Castagnola P., et al., 1986). Continuous treatment of chondrogenic cells in conditions allowing differentiation "in vitro" with Retinoic acid resulted in persistence of type I collagen synthesis and in lack of type X collagen and Ch 21 protein expression. Hemin treated cells secreted a reduced amount of type X collagen. HMBA treatment inhibited type X collagen expression and caused reduction of the ratio between type II collagen and Ch 21 synthesized. The data indicate an independent regulation of these markers during chondrocyte differentiation.

In vitro effects of cisplatin-functionalized silica nanoparticles on chondrocytes

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Bhowmick, Tridib Kumar; Yoon, Diana [University of Maryland, Department of Chemical and Biomolecular Engineering (United States); Patel, Minal; Fisher, John [University of Maryland, Fischell Department of Bioengineering (United States); Ehrman, Sheryl, E-mail: sehrman@umd.ed [University of Maryland, Department of Chemical and Biomolecular Engineering (United States)

2010-10-15

In this study, we evaluated the combined effect of a known toxic molecule, cisplatin, in combination with relatively nontoxic nanoparticles, amorphous fumed silica, on chondrocyte cells. Cisplatin was attached to silica nanoparticles using aminopropyltriethoxy silane as a linker molecule, and characterized in terms of size, shape, specific surface area, as well as the dissolution of cisplatin from the silica surface. The primary particle diameter of the as-received silica nanoparticles ranged from 7.1 to 61 nm, estimated from measurements of specific surface area, and the primary particles were aggregated. The effects of cisplatin-functionalized silica particles with different specific surface areas (41, 85, 202, 237, and 297 m{sup 2}/g) were compared in vitro on chondrocytes, the parenchymal cell of hyaline cartilage. The results show that adverse effects on cell function, as evidenced by reduced metabolic activity measured by the MTT assay and increased membrane permeability observed using the Live/Dead stain, can be correlated with specific surface area of the silica. Cisplatin-functionalized silica nanoparticles with the highest specific surface area incited the greatest response, which was almost equivalent to that induced by free cisplatin. This result suggests the importance of particle specific surface area in interactions between cells and surface-functionalized nanomaterials.

In vitro effects of cisplatin-functionalized silica nanoparticles on chondrocytes

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Bhowmick, Tridib Kumar; Yoon, Diana; Patel, Minal; Fisher, John; Ehrman, Sheryl

2010-10-01

In this study, we evaluated the combined effect of a known toxic molecule, cisplatin, in combination with relatively nontoxic nanoparticles, amorphous fumed silica, on chondrocyte cells. Cisplatin was attached to silica nanoparticles using aminopropyltriethoxy silane as a linker molecule, and characterized in terms of size, shape, specific surface area, as well as the dissolution of cisplatin from the silica surface. The primary particle diameter of the as-received silica nanoparticles ranged from 7.1 to 61 nm, estimated from measurements of specific surface area, and the primary particles were aggregated. The effects of cisplatin-functionalized silica particles with different specific surface areas (41, 85, 202, 237, and 297 m2/g) were compared in vitro on chondrocytes, the parenchymal cell of hyaline cartilage. The results show that adverse effects on cell function, as evidenced by reduced metabolic activity measured by the MTT assay and increased membrane permeability observed using the Live/Dead stain, can be correlated with specific surface area of the silica. Cisplatin-functionalized silica nanoparticles with the highest specific surface area incited the greatest response, which was almost equivalent to that induced by free cisplatin. This result suggests the importance of particle specific surface area in interactions between cells and surface-functionalized nanomaterials.

Globular Adiponectin Attenuated H2O2-Induced Apoptosis in Rat Chondrocytes by Inducing Autophagy Through the AMPK/ mTOR Pathway.

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Hu, Junzheng; Cui, Weiding; Ding, Wenxiao; Gu, Yanqing; Wang, Zhen; Fan, Weimin

2017-01-01

Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN), secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. H2O2 (400 µM)-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL). gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of H2O2-induced chondrocytes apoptosis by gAPN. g

Globular Adiponectin Attenuated H2O2-Induced Apoptosis in Rat Chondrocytes by Inducing Autophagy Through the AMPK/ mTOR Pathway

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Junzheng Hu

2017-08-01

Full Text Available Background/Aims: Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN, secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. Methods: H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. Results: H2O2 (400 µM-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL. gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of

miR-139 is up-regulated in osteoarthritis and inhibits chondrocyte proliferation and migration possibly via suppressing EIF4G2 and IGF1R

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Hu, Weihua; Zhang, Weikai; Li, Feng; Guo, Fengjing; Chen, Anmin, E-mail: chenanmin6072@126.com

2016-05-27

Osteoarthritis (OA) is one of the most progressive articular cartilage erosions. microRNAs (miRNAs) play pivotal roles in OA modulation, but the role of miR-139 in OA remains elusive. This study aims to reveal the effects and possible mechanism of miR-139 in OA and chondrocytes. The levels of miR-139 and its possible targets eukaryotic translation initiation factor 4 gamma 2 (EIF4G2) and insulin-like growth factor 1 receptor (IGF1R) were detected by qRT-PCR in the articular cartilages of 20 OA patients and 20 non-OA patients. Human chondrocyte CHON-001 cells were transfected with miR-139 mimic or inhibitor, as well as the siRNAs of EIF4G2 and IGF1R. Cell viability by MTT assay, proliferation by colony formation assay and migration by Transwell assay were performed. Results showed that miR-139 was up-regulated, while EIF4G2 and IGF1R mRNAs down-regulated in OA cartilages (P < 0.001), and negative correlations existed between the level of miR-139 and EIF4G2 or IGF1R. Overexpression of miR-139 in CHON-001 cells suppressed both mRNA and protein levels of EIF4G2 and IGF1R, and inhibited cell viability, colony formation number and cell migration, while miR-139 inhibitor induced the opposite effects. Knockdown of EIF4G2 or IGF1R in CHON-001 cells reversed the effects of miR-139 inhibitor on cell viability, colony formation and cell migration. These results indicate that miR-139 is capable of inhibiting chondrocyte proliferation and migration, thus being a possible therapeutic target for OA. The mechanism of miR-139 in chondrocytes may be related to its regulation on EIF4G2 and IGF1R.

Ofloxacin induces apoptosis in microencapsulated juvenile rabbit chondrocytes by caspase-8-dependent mitochondrial pathway

International Nuclear Information System (INIS)

Sheng Zhiguo; Cao Xiaojuan; Peng Shuangqing; Wang Changyong; Li Qianqian; Wang Yimei; Liu Mifeng

2008-01-01

Quinolones (QNs)-induced arthropathy is an important toxic effect in immature animals leading to restriction of their therapeutic use in pediatrics. However, the exact mechanism still remains unclear. Recently, we have demonstrated that ofloxacin, a typical QN, induces apoptosis of alginate microencapsulated juvenile rabbit joint chondrocytes by disturbing the β 1 integrin functions and inactivating the ERK/MAPK signaling pathway. In this study, we extend our initial observations to further elucidate the mechanism(s) of ofloxacin-induced apoptosis by utilizing specific caspase inhibitors. Pretreatment with both caspase-9-specific inhibitor zLEHD-fmk and caspase-8 inhibitor zIETD-fmk attenuated ofloxacin-induced apoptosis and activation of caspase-3 of chondrocyte in a concentration-dependent manner, as determined by fluorescent dye staining, enzyme activity assay and immunoblotting. Furthermore, the activation of caspase-9, -8 and -3 stimulated by ofloxacin was significantly inhibited in the presence of zIETD-fmk while pretreatment with zLEHD-fmk only blocked the activation of caspase-9 and -3. Ofloxacin also stimulated a concentration-dependent translocation of cytochrome c from mitochondria into the cytosol and a decrease of mitochondrial transmembrane potential, which was completely inhibited by zIETD-fmk. In addition, ofloxacin was found to increase the level of Bax, tBid, p53 in a concentration- and time-dependent manner. Taken together, The current results indicate that the caspase-8-dependent mitochondrial pathway is primarily involved in the ofloxacin-induced apoptosis of microencapsulated juvenile rabbit joint chondrocytes

From gristle to chondrocyte transplantation: treatment of cartilage injuries.

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Lindahl, Anders

2015-10-19

This review addresses the progress in cartilage repair technology over the decades with an emphasis on cartilage regeneration with cell therapy. The most abundant cartilage is the hyaline cartilage that covers the surface of our joints and, due to avascularity, this tissue is unable to repair itself. The cartilage degeneration seen in osteoarthritis causes patient suffering and is a huge burden to society. The surgical approach to cartilage repair was non-existing until the 1950s when new surgical techniques emerged. The use of cultured cells for cell therapy started as experimental studies in the 1970s that developed over the years to a clinical application in 1994 with the introduction of the autologous chondrocyte transplantation technique (ACT). The technology is now spread worldwide and has been further refined by combining arthroscopic techniques with cells cultured on matrix (MACI technology). The non-regenerating hypothesis of cartilage has been revisited and we are now able to demonstrate cell divisions and presence of stem-cell niches in the joint. Furthermore, cartilage derived from human embryonic stem cells and induced pluripotent stem cells could be the base for new broader cell treatments for cartilage injuries and the future technology base for prevention and cure of osteoarthritis. © 2015 The Author(s).

From gristle to chondrocyte transplantation: treatment of cartilage injuries

Science.gov (United States)

Lindahl, Anders

2015-01-01

This review addresses the progress in cartilage repair technology over the decades with an emphasis on cartilage regeneration with cell therapy. The most abundant cartilage is the hyaline cartilage that covers the surface of our joints and, due to avascularity, this tissue is unable to repair itself. The cartilage degeneration seen in osteoarthritis causes patient suffering and is a huge burden to society. The surgical approach to cartilage repair was non-existing until the 1950s when new surgical techniques emerged. The use of cultured cells for cell therapy started as experimental studies in the 1970s that developed over the years to a clinical application in 1994 with the introduction of the autologous chondrocyte transplantation technique (ACT). The technology is now spread worldwide and has been further refined by combining arthroscopic techniques with cells cultured on matrix (MACI technology). The non-regenerating hypothesis of cartilage has been revisited and we are now able to demonstrate cell divisions and presence of stem-cell niches in the joint. Furthermore, cartilage derived from human embryonic stem cells and induced pluripotent stem cells could be the base for new broader cell treatments for cartilage injuries and the future technology base for prevention and cure of osteoarthritis. PMID:26416680

Effect of hyaluronic acid and polysaccharides from Opuntia ficus indica (L.) cladodes on the metabolism of human chondrocyte cultures.

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Panico, A M; Cardile, V; Garufi, F; Puglia, C; Bonina, F; Ronsisvalle, S

2007-05-04

Conventional medications in articular disease are often effective for symptom relief, but they can also cause significant side effects and do not slow the progression of the disease. Several natural substances have been shown to be effective as non-steroidal anti-inflammatory drugs at relieving the symptoms of osteoarthritis (OA), and preliminary evidence suggests that some of these compounds may exert a favourable influence on the course of the disease. In this study, we assay the anti-inflammatory/chondroprotective effect of some lyophilised extracts obtained from Opuntia ficus indica (L.) cladodes and of hyaluronic acid (HA) on the production of key molecules released during chronic inflammatory events such as nitric oxide (NO), glycosaminoglycans (GAGs), prostaglandins (PGE(2)) and reactive oxygen species (ROS) in human chondrocyte culture, stimulated with proinflammatory cytokine interleukin-1 beta (IL-1 beta). Further the antioxidant effect of these extracts was evaluated in vitro employing the bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical (DPPH test). All the extracts tested in this study showed an interesting profile in active compounds. Particularly some of these extracts were characterized by polyphenolic and polysaccharidic species. In vitro results pointed out that the extracts of Opuntia ficus indica cladodes were able to contrast the harmful effects of IL-1 beta. Our data showed the protective effect of the extracts of Opuntia ficus indica cladodes in cartilage alteration, which appears greater than that elicited by hyaluronic acid (HA) commonly employed as visco-supplementation in the treatment of joint diseases.

Nicotine-induced retardation of chondrogenesis through down-regulation of IGF-1 signaling pathway to inhibit matrix synthesis of growth plate chondrocytes in fetal rats

International Nuclear Information System (INIS)

Deng, Yu; Cao, Hong; Cu, Fenglong; Xu, Dan; Lei, Youying; Tan, Yang; Magdalou, Jacques; Wang, Hui; Chen, Liaobin

2013-01-01

Previous studies have confirmed that maternal tobacco smoking causes intrauterine growth retardation (IUGR) and skeletal growth retardation. Among a multitude of chemicals associated with cigarette smoking, nicotine is one of the leading candidates for causing low birth weights. However, the possible mechanism of delayed chondrogenesis by prenatal nicotine exposure remains unclear. We investigated the effects of nicotine on fetal growth plate chondrocytes in vivo and in vitro. Rats were given 2.0 mg/kg·d of nicotine subcutaneously from gestational days 11 to 20. Prenatal nicotine exposure increased the levels of fetal blood corticosterone and resulted in fetal skeletal growth retardation. Moreover, nicotine exposure induced the inhibition of matrix synthesis and down-regulation of insulin-like growth factor 1 (IGF-1) signaling in fetal growth plates. The effects of nicotine on growth plates were studied in vitro by exposing fetal growth plate chondrocytes to 0, 1, 10, or 100 μM of nicotine for 10 days. Nicotine inhibited matrix synthesis and down-regulated IGF-1 signaling in chondrocytes in a concentration-dependent manner. These results suggest that prenatal nicotine exposure induces delayed chondrogenesis and that the mechanism may involve the down-regulation of IGF-1 signaling and the inhibition of matrix synthesis by growth plate chondrocytes. The present study aids in the characterization of delayed chondrogenesis caused by prenatal nicotine exposure, which might suggest a candidate mechanism for intrauterine origins of osteoporosis and osteoarthritis. - Highlights: ► Prenatal nicotine-exposure could induce delayed chondrogenesis in fetal rats. ► Nicotine inhibits matrix synthesis of fetal growth plate chondrocytes. ► Nicotine inhibits IGF-1 signaling pathway in fetal growth plate chondrocytes

Nicotine-induced retardation of chondrogenesis through down-regulation of IGF-1 signaling pathway to inhibit matrix synthesis of growth plate chondrocytes in fetal rats

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Deng, Yu; Cao, Hong; Cu, Fenglong [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Xu, Dan [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China); Lei, Youying [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Tan, Yang [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Magdalou, Jacques [UMR 7561 CNRS-Nancy Université, Faculté de Médicine, Vandoeuvre-lès-Nancy (France); Wang, Hui [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China); Chen, Liaobin, E-mail: lbchen@whu.edu.cn [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China)

2013-05-15

Previous studies have confirmed that maternal tobacco smoking causes intrauterine growth retardation (IUGR) and skeletal growth retardation. Among a multitude of chemicals associated with cigarette smoking, nicotine is one of the leading candidates for causing low birth weights. However, the possible mechanism of delayed chondrogenesis by prenatal nicotine exposure remains unclear. We investigated the effects of nicotine on fetal growth plate chondrocytes in vivo and in vitro. Rats were given 2.0 mg/kg·d of nicotine subcutaneously from gestational days 11 to 20. Prenatal nicotine exposure increased the levels of fetal blood corticosterone and resulted in fetal skeletal growth retardation. Moreover, nicotine exposure induced the inhibition of matrix synthesis and down-regulation of insulin-like growth factor 1 (IGF-1) signaling in fetal growth plates. The effects of nicotine on growth plates were studied in vitro by exposing fetal growth plate chondrocytes to 0, 1, 10, or 100 μM of nicotine for 10 days. Nicotine inhibited matrix synthesis and down-regulated IGF-1 signaling in chondrocytes in a concentration-dependent manner. These results suggest that prenatal nicotine exposure induces delayed chondrogenesis and that the mechanism may involve the down-regulation of IGF-1 signaling and the inhibition of matrix synthesis by growth plate chondrocytes. The present study aids in the characterization of delayed chondrogenesis caused by prenatal nicotine exposure, which might suggest a candidate mechanism for intrauterine origins of osteoporosis and osteoarthritis. - Highlights: ► Prenatal nicotine-exposure could induce delayed chondrogenesis in fetal rats. ► Nicotine inhibits matrix synthesis of fetal growth plate chondrocytes. ► Nicotine inhibits IGF-1 signaling pathway in fetal growth plate chondrocytes.

Phlpp1 facilitates post-traumatic osteoarthritis and is induced by inflammation and promoter demethylation in human osteoarthritis

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Bradley, Elizabeth W.; Carpio, Lomeli R.; McGee-Lawrence, Meghan E.; Becerra, Clara Castillejo; Amanatullah, Derek F.; Ta, Lauren E.; Otero, Miguel; Goldring, Mary B.; Kakar, Sanjeev; Westendorf, Jennifer J.

2016-01-01

OBJECTIVE Osteoarthritis (OA) is the most common form of arthritis and a leading cause of disability. OA is characterized by articular chondrocyte deterioration, subchondral bone changes and debilitating pain. One strategy to promote cartilage regeneration and repair is to accelerate proliferation and matrix production of articular chondrocytes. We previously reported that the protein phosphatase Phlpp1 controls chondrocyte differentiation by regulating the activities of anabolic kinases. Here we examined the role of Phlpp1 in osteoarthritis progression in a murine model. We also assessed PHLPP1 expression and promoter methylation. DESIGN Knee joints of WT and Phlpp1−/− mice were surgically destabilized by transection of the medial meniscal ligament (DMM). Mice were assessed for signs of OA progression via radiographic and histological analyses, and pain assessment for mechanical hypersensitivity using the von Frey assay. Methylation of the PHLPP1 promoter and PHLPP1 expression was evaluated in human articular cartilage and chondrocyte cell lines. RESULTS Following DMM surgeries, Phlpp1 deficient mice showed fewer signs of OA and cartilage degeneration. Mechanical allodynia associated with DMM surgeries was also attenuated in Phlpp1−/− mice. PHLPP1 was highly expressed in human articular cartilage from OA patients, but was undetectable in cartilage specimens from femoral neck fractures. Higher PHLPP1 levels correlated with less PHLPP1 promoter CpG methylation in cartilage from OA patients. Blocking cytosine methylation or treatment with inflammatory mediators enhanced PHLPP1 expression in human chondrocyte cell lines. CONCLUSION Phlpp1 deficiency protects against OA progression while CpG demethylation and inflammatory responses promote PHLPP1 expression. PMID:26746148

Clinical outcome 3 years after autologous chondrocyte implantation does not correlate with the expression of a predefined gene marker set in chondrocytes prior to implantation but is associated with critical signaling pathways

NARCIS (Netherlands)

Stenberg, Johan; de Windt, Tommy S.; Synnergren, Jane; Hynsjö, Lars; van der Lee, Josefine; Saris, Daniël B.F.; Brittberg, Mats; Peterson, Lars; Lindahl, Anders

2014-01-01

Background: There is a need for tools to predict the chondrogenic potency of autologous cells for cartilage repair. Purpose: To evaluate previously proposed chondrogenic biomarkers and to identify new biomarkers in the chondrocyte transcriptome capable of predicting clinical success or failure after

A combined approach for the assessment of cell viability and cell functionality of human fibrochondrocytes for use in tissue engineering.

Science.gov (United States)

Garzón, Ingrid; Carriel, Victor; Marín-Fernández, Ana Belén; Oliveira, Ana Celeste; Garrido-Gómez, Juan; Campos, Antonio; Sánchez-Quevedo, María Del Carmen; Alaminos, Miguel

2012-01-01

Temporo-mandibular joint disc disorders are highly prevalent in adult populations. Autologous chondrocyte implantation is a well-established method for the treatment of several chondral defects. However, very few studies have been carried out using human fibrous chondrocytes from the temporo-mandibular joint (TMJ). One of the main drawbacks associated to chondrocyte cell culture is the possibility that chondrocyte cells kept in culture tend to de-differentiate and to lose cell viability under in in-vitro conditions. In this work, we have isolated human temporo-mandibular joint fibrochondrocytes (TMJF) from human disc and we have used a highly-sensitive technique to determine cell viability, cell proliferation and gene expression of nine consecutive cell passages to determine the most appropriate cell passage for use in tissue engineering and future clinical use. Our results revealed that the most potentially viable and functional cell passages were P5-P6, in which an adequate equilibrium between cell viability and the capability to synthesize all major extracellular matrix components exists. The combined action of pro-apoptotic (TRAF5, PHLDA1) and anti-apoptotic genes (SON, HTT, FAIM2) may explain the differential cell viability levels that we found in this study. These results suggest that TMJF should be used at P5-P6 for cell therapy protocols.

Influence of Knee Immobilization on Chondrocyte Apoptosis and Histological Features of the Anterior Cruciate Ligament Insertion and Articular Cartilage in Rabbits.

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Mutsuzaki, Hirotaka; Nakajima, Hiromi; Wadano, Yasuyoshi; Furuhata, Syogo; Sakane, Masataka

2017-01-26

This study examined the influence of immobilization on chondrocyte apoptosis and histological features of the anterior cruciate ligament (ACL) insertion and knee articular cartilage in rabbits. Forty-eight male Japanese white rabbits were assigned to an immobilization ( n = 24) or sham ( n = 24) group. Rabbits in the immobilization group underwent complete unilateral surgical knee immobilization and rabbits in the sham group underwent a sham surgery. The average thickness of the glycosaminoglycan (GAG) stained red area by safranin O staining, the chondrocyte apoptosis rate and the chondrocyte proliferation rate in the cartilage layer in the ACL insertion and the articular cartilage of the medial tibial condyle were measured at one, two, four and eight weeks in six animals from each group. In the ACL insertion, the chondrocyte apoptosis rate was higher in the immobilization group than in the sham group at two and eight weeks after surgery ( p immobilization group. The GAG layer was thinner in the immobilization group than in the sham group at two, four and eight weeks after surgery ( p immobilization group was higher than in the sham group at four and eight weeks after surgery ( p immobilization group than that in the sham group at four and eight weeks after surgery ( p immobilization significantly increased chondrocyte apoptosis at two and eight weeks after surgery in the ACL insertion and at four and eight weeks after surgery in the articular cartilage of the medial tibial condyle, and decreased GAG layer thickness from two to eight weeks after surgery in the ACL insertion and from four to eight weeks after surgery in the articular cartilage.

Smad2 and Smad3 Regulate Chondrocyte Proliferation and Differentiation in the Growth Plate.

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Weiguang Wang

2016-10-01

Full Text Available TGFβs act through canonical and non-canonical pathways, and canonical signals are transduced via Smad2 and Smad3. However, the contribution of canonical vs. non-canonical pathways in cartilage is unknown because the role of Smad2 in chondrogenesis has not been investigated in vivo. Therefore, we analyzed mice in which Smad2 is deleted in cartilage (Smad2CKO, global Smad3-/- mutants, and crosses of these strains. Growth plates at birth from all mutant strains exhibited expanded columnar and hypertrophic zones, linked to increased proliferation in resting chondrocytes. Defects were more severe in Smad2CKO and Smad2CKO;Smad3-/- (Smad2/3 mutant mice than in Smad3-/- mice, demonstrating that Smad2 plays a role in chondrogenesis. Increased levels of Ihh RNA, a key regulator of chondrocyte proliferation and differentiation, were seen in prehypertrophic chondrocytes in the three mutant strains at birth. In accordance, TGFβ treatment decreased Ihh RNA levels in primary chondrocytes from control (Smad2fx/fx mice, but inhibition was impaired in cells from mutants. Consistent with the skeletal phenotype, the impact on TGFβ-mediated inhibition of Ihh RNA expression was more severe in Smad2CKO than in Smad3-/- cells. Putative Smad2/3 binding elements (SBEs were identified in the proximal Ihh promoter. Mutagenesis demonstrated a role for three of them. ChIP analysis suggested that Smad2 and Smad3 have different affinities for these SBEs, and that the repressors SnoN and Ski were differentially recruited by Smad2 and Smad3, respectively. Furthermore, nuclear localization of the repressor Hdac4 was decreased in growth plates of Smad2CKO and double mutant mice. TGFβ induced association of Hdac4 with Smad2, but not with Smad3, on the Ihh promoter. Overall, these studies revealed that Smad2 plays an essential role in the development of the growth plate, that both Smads 2 and 3 inhibit Ihh expression in the neonatal growth plate, and suggested they accomplish

Smad2 and Smad3 Regulate Chondrocyte Proliferation and Differentiation in the Growth Plate

Science.gov (United States)

Wang, Weiguang; Song, Buer; Anbarchian, Teni; Shirazyan, Anna

2016-01-01

TGFβs act through canonical and non-canonical pathways, and canonical signals are transduced via Smad2 and Smad3. However, the contribution of canonical vs. non-canonical pathways in cartilage is unknown because the role of Smad2 in chondrogenesis has not been investigated in vivo. Therefore, we analyzed mice in which Smad2 is deleted in cartilage (Smad2CKO), global Smad3-/- mutants, and crosses of these strains. Growth plates at birth from all mutant strains exhibited expanded columnar and hypertrophic zones, linked to increased proliferation in resting chondrocytes. Defects were more severe in Smad2CKO and Smad2CKO;Smad3-/- (Smad2/3) mutant mice than in Smad3-/- mice, demonstrating that Smad2 plays a role in chondrogenesis. Increased levels of Ihh RNA, a key regulator of chondrocyte proliferation and differentiation, were seen in prehypertrophic chondrocytes in the three mutant strains at birth. In accordance, TGFβ treatment decreased Ihh RNA levels in primary chondrocytes from control (Smad2fx/fx) mice, but inhibition was impaired in cells from mutants. Consistent with the skeletal phenotype, the impact on TGFβ-mediated inhibition of Ihh RNA expression was more severe in Smad2CKO than in Smad3-/- cells. Putative Smad2/3 binding elements (SBEs) were identified in the proximal Ihh promoter. Mutagenesis demonstrated a role for three of them. ChIP analysis suggested that Smad2 and Smad3 have different affinities for these SBEs, and that the repressors SnoN and Ski were differentially recruited by Smad2 and Smad3, respectively. Furthermore, nuclear localization of the repressor Hdac4 was decreased in growth plates of Smad2CKO and double mutant mice. TGFβ induced association of Hdac4 with Smad2, but not with Smad3, on the Ihh promoter. Overall, these studies revealed that Smad2 plays an essential role in the development of the growth plate, that both Smads 2 and 3 inhibit Ihh expression in the neonatal growth plate, and suggested they accomplish this by binding to

Human YKL39 (chitinase 3-like protein 2), an osteoarthritis-associated gene, enhances proliferation and type II collagen expression in ATDC5 cells

International Nuclear Information System (INIS)

Miyatake, Kazumasa; Tsuji, Kunikazu; Yamaga, Mika; Yamada, Jun; Matsukura, Yu; Abula, Kahaer; Sekiya, Ichiro; Muneta, Takeshi

2013-01-01

Highlights: ► hYKL-39 expression is increased in osteoarthritic articular chondrocytes. ► To examine the molecular functions of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in chondrocytic ATDC5 cells. ► hYKL-39 enhanced proliferation and colony formation in ATDC5 cells. ► hYKL-39 increased type II collagen expression in ATDC5 cells treated with chondrogenic medium. -- Abstract: Human YKL39 (chitinase 3-like protein 2/CHI3L2) is a secreted 39 kDa protein produced by articular chondrocytes and synoviocytes. Recent studies showed that hYKL-39 expression is increased in osteoarthritic articular chondrocytes suggesting the involvement of hYKL-39 in the progression of osteoarthritis (OA). However little is known regarding the molecular function of hYKL-39 in joint homeostasis. Sequence analyses indicated that hYKL-39 has significant identity with the human chitotorisidase family molecules, although it is considered that hYKL-39 has no enzymatic activity since it lacks putative chitinase catalytic motif. In this study, to examine the molecular function of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in ATDC5 cells. Here we report that hYKL-39 enhances colony forming activity, cell proliferation, and type II collagen expression in these cells. These data suggest that hYKL-39 is a novel growth and differentiation factor involved in cartilage homeostasis

Human YKL39 (chitinase 3-like protein 2), an osteoarthritis-associated gene, enhances proliferation and type II collagen expression in ATDC5 cells

Energy Technology Data Exchange (ETDEWEB)

Miyatake, Kazumasa [Department of Joint Surgery and Sports Medicine, Tokyo Medical and Dental University, Tokyo (Japan); Tsuji, Kunikazu, E-mail: ktsuji.gcoe@tmd.ac.jp [International Research Center for Molecular Science in Tooth and Bone Diseases (Global Center of Excellence Program), Tokyo Medical and Dental University, Tokyo (Japan); Yamaga, Mika; Yamada, Jun; Matsukura, Yu; Abula, Kahaer [Department of Joint Surgery and Sports Medicine, Tokyo Medical and Dental University, Tokyo (Japan); Sekiya, Ichiro [Section of Cartilage Regeneration, Tokyo Medical and Dental University, Tokyo (Japan); Muneta, Takeshi [Department of Joint Surgery and Sports Medicine, Tokyo Medical and Dental University, Tokyo (Japan); International Research Center for Molecular Science in Tooth and Bone Diseases (Global Center of Excellence Program), Tokyo Medical and Dental University, Tokyo (Japan)

2013-02-01

Highlights: ► hYKL-39 expression is increased in osteoarthritic articular chondrocytes. ► To examine the molecular functions of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in chondrocytic ATDC5 cells. ► hYKL-39 enhanced proliferation and colony formation in ATDC5 cells. ► hYKL-39 increased type II collagen expression in ATDC5 cells treated with chondrogenic medium. -- Abstract: Human YKL39 (chitinase 3-like protein 2/CHI3L2) is a secreted 39 kDa protein produced by articular chondrocytes and synoviocytes. Recent studies showed that hYKL-39 expression is increased in osteoarthritic articular chondrocytes suggesting the involvement of hYKL-39 in the progression of osteoarthritis (OA). However little is known regarding the molecular function of hYKL-39 in joint homeostasis. Sequence analyses indicated that hYKL-39 has significant identity with the human chitotorisidase family molecules, although it is considered that hYKL-39 has no enzymatic activity since it lacks putative chitinase catalytic motif. In this study, to examine the molecular function of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in ATDC5 cells. Here we report that hYKL-39 enhances colony forming activity, cell proliferation, and type II collagen expression in these cells. These data suggest that hYKL-39 is a novel growth and differentiation factor involved in cartilage homeostasis.

Inhibition of T-Type Voltage Sensitive Calcium Channel Reduces Load-Induced OA in Mice and Suppresses the Catabolic Effect of Bone Mechanical Stress on Chondrocytes.

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Padma P Srinivasan

Full Text Available Voltage-sensitive calcium channels (VSCC regulate cellular calcium influx, one of the earliest responses to mechanical stimulation in osteoblasts. Here, we postulate that T-type VSCCs play an essential role in bone mechanical response to load and participate in events leading to the pathology of load-induced OA. Repetitive mechanical insult was used to induce OA in Cav3.2 T-VSCC null and wild-type control mouse knees. Osteoblasts (MC3T3-E1 and chondrocytes were treated with a selective T-VSCC inhibitor and subjected to fluid shear stress to determine how blocking of T-VSCCs alters the expression profile of each cell type upon mechanical stimulation. Conditioned-media (CM obtained from static and sheared MC3T3-E1 was used to assess the effect of osteoblast-derived factors on the chondrocyte phenotype. T-VSCC null knees exhibited significantly lower focal articular cartilage damage than age-matched controls. In vitro inhibition of T-VSCC significantly reduced the expression of both early and late mechanoresponsive genes in osteoblasts but had no effect on gene expression in chondrocytes. Furthermore, treatment of chondrocytes with CM obtained from sheared osteoblasts induced expression of markers of hypertrophy in chondrocytes and this was nearly abolished when osteoblasts were pre-treated with the T-VSCC-specific inhibitor. These results indicate that T-VSCC plays a role in signaling events associated with induction of OA and is essential to the release of osteoblast-derived factors that promote an early OA phenotype in chondrocytes. Further, these findings suggest that local inhibition of T-VSCC may serve as a therapy for blocking load-induced bone formation that results in cartilage degeneration.