Effect of injection molded micro-structured polystyrene surfaces on proliferation of MC3T3-E1 cells

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G. Lucchetta

2015-04-01

Full Text Available In this work, osteoinductive micro-pillared polystyrene surfaces were mass-produced for bone replacement applications, by means of the micro injection molding process. Firstly, the molding process parameters were optimized with a two-level, three-factor central composite face-centered plan to increase the quality of polystyrene micro pillars replication and to maximize the pillars height uniformity over the molded part. Secondly, osteoblastic MC3T3-E1 cells adhesion and proliferation on the replicated substrates were assessed as a function of micro topography parameters, such as pillars diameter, aspect ratio and spacing. Cell morphology and proliferation were evaluated through MTS test after 1, 3 and 7 days from seeding. The experimental results showed that cells adhesion and proliferation is more positively promoted on micro-pillared surfaces compared to flat surfaces, but no correlations were observed between cell proliferation and pillar diameter and spacing.

Protective effect of Edaravone against hypoxia-induced cytotoxicity in osteoblasts MC3T3-E1 cells.

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Cao, Bo; Chai, Chunxiang; Zhao, Sishun

2015-12-01

Edaravone is a newly developed clinical medicine for the treatment of acute cerebral infarction. Reduced blood supply to bones (hypoxia) has been involved in the pathological development of osteoporosis. In this study, we investigated the effect of Edaravone and its latent mechanism on hypoxia-induced cell toxicity in MC3T3-E1 cells. Cell viability was determined by the 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Intracellular reactive oxygen species (ROS) and nitric oxide (NO) were determined by the fluorescence dyes 2',7'-dichlorofluorescein diacetate (DCFH-DA) and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM DA), respectively. mRNA and proteins were determined by real-time polymerase chain reaction and Western blot analysis, respectively. Edaravone significantly restored the hypoxia-induced reduction of MC3T3-E1 cell viability and inhibited lactate dehydrogenase release. In addition, we found that Edaravone inhibits the generation of ROS and NO. Hoechst staining results indicated that the nuclear condensation characteristic of apoptosis was increased in MC3T3-E1 cells after hypoxia exposure, which was significantly suppressed by Edaravone treatment. Mechanistically, we found that Edaravone markedly reduced the expression of cleaved caspase-3 and blunted the release of cytochrome c. These findings strongly suggested that Edaravone suppresses hypoxia-induced cytotoxicity in MC3T3-E1 cells. The pleiotropic effects of Edaravone on hypoxia exposure in osteoblasts suggest potential antiosteoporosis mechanisms of Edaravone. © 2015 International Union of Biochemistry and Molecular Biology.

Functional expression of 5-HT{sub 2A} receptor in osteoblastic MC3T3-E1 cells

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Hirai, Takao; Kaneshige, Kota; Kurosaki, Teruko [Department of Molecular Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Gakuen-cho, Fukuyama, Hiroshima 729-0292 (Japan); Nishio, Hiroaki, E-mail: nishio@fupharm.fukuyama-u.ac.jp [Department of Molecular Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, 1 Gakuen-cho, Fukuyama, Hiroshima 729-0292 (Japan)

2010-05-28

In the previous study, we reported the gene expression for proteins related to the function of 5-hydroxytryptamine (5-HT, serotonin) and elucidated the expression patterns of 5-HT{sub 2} receptor subtypes in mouse osteoblasts. In the present study, we evaluated the possible involvement of 5-HT receptor subtypes and its inactivation system in MC3T3-E1 cells, an osteoblast cell line. DOI, a 5-HT{sub 2A} and 5-HT{sub 2C} receptor selective agonist, as well as 5-HT concentration-dependently increased proliferative activities of MC3T3-E1 cells in their premature period. This effect of 5-HT on cell proliferation were inhibited by ketanserin, a 5-HT{sub 2A} receptor specific antagonist. Moreover, both DOI-induced cell proliferation and phosphorylation of ERK1 and 2 proteins were inhibited by PD98059 and U0126, selective inhibitors of MEK in a concentration-dependent manner. Furthermore, treatment with fluoxetine, a 5-HT specific re-uptake inhibitor which inactivate the function of extracellular 5-HT, significantly increased the proliferative activities of MC3T3-E1 cells in a concentration-dependent manner. Our data indicate that 5-HT fill the role for proliferation of osteoblast cells in their premature period. Notably, 5-HT{sub 2A} receptor may be functionally expressed to regulate mechanisms underlying osteoblast cell proliferation, at least in part, through activation of ERK/MAPK pathways in MC3T3-E1 cells.

ClC-3 Promotes Osteogenic Differentiation in MC3T3-E1 Cell After Dynamic Compression.

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Wang, Dawei; Wang, Hao; Gao, Feng; Wang, Kun; Dong, Fusheng

2017-06-01

ClC-3 chloride channel has been proved to have a relationship with the expression of osteogenic markers during osteogenesis, persistent static compression can upregulate the expression of ClC-3 and regulate osteodifferentiation in osteoblasts. However, there was no study about the relationship between the expression of ClC-3 and osteodifferentiation after dynamic compression. In this study, we applied dynamic compression on MC3T3-E1 cells to detect the expression of ClC-3, runt-related transcription factor 2 (Runx2), bone morphogenic protein-2 (BMP-2), osteopontin (OPN), nuclear-associated antigen Ki67 (Ki67), and proliferating cell nuclear antigen (PCNA) in biopress system, then we investigated the expression of these genes after dynamic compression with Chlorotoxin (specific ClC-3 chloride channel inhibitor) added. Under transmission electron microscopy, there were more cell surface protrusions, rough surfaced endoplasmic reticulum, mitochondria, Golgi apparatus, abundant glycogen, and lysosomes scattered in the cytoplasm in MC3T3-E1 cells after dynamic compression. The nucleolus was more obvious. We found that ClC-3 was significantly up-regulated after dynamic compression. The compressive force also up-regulated Runx2, BMP-2, and OPN after dynamic compression for 2, 4 and 8 h. The proliferation gene Ki67 and PCNA did not show significantly change after dynamic compression for 8 h. Chlorotoxin did not change the expression of ClC-3 but reduced the expression of Runx2, BMP-2, and OPN after dynamic compression compared with the group without Cltx added. The data from the current study suggested that ClC-3 may promotes osteogenic differentiation in MC3T3-E1 cell after dynamic compression. J. Cell. Biochem. 118: 1606-1613, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Nano-hydroxyapatite particles induce apoptosis on MC3T3-E1 cells and tissue cells in SD rats

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Wang, Liting; Zhou, Gang; Liu, Haifeng; Niu, Xufeng; Han, Jingyun; Zheng, Lisha; Fan, Yubo

2012-04-01

While the advantages of nanomaterials are being increasingly recognized, their potential toxicity is drawing more and more attention and concern. In this study, we explore the toxicity mechanism of 20-30 nm rod-shaped hydroxyapatite (HA) nanoparticles in vitro and in vivo. The nanoparticles were prepared by precipitation and characterized by IR, XRD and TEM. Concentrations of 0 μg mL-1, 10 μg mL-1, 100 μg mL-1, 1 mg mL-1, and 10 mg mL-1 were applied to the MC3T3-E1 cells for viability (MTT-test). Based on the characteristic differences of the two methods of cell death, the morphological features of the MC3T3-E1 cell line co-cultured with nano-hydroxyapatite (n-HA) (10 mg mL-1) for 24 h were also observed by TEM. Furthermore, important serum biochemical markers and histopathological examinations were used to evaluate the potential toxicological effect of n-HA on the major organs of SD rats injected intraperitoneally with n-HA (33.3 mg kg-1 body weight). In the results, we found cell growth inhibition and apoptosis in MC3T3-E1 cells co-cultured with n-HA. Moreover, apoptosis but not necrosis was illustrated in liver and renal tissue by using histopathology slices and serum biochemical markers. It suggests that apoptosis may be the possible mechanism of n-HA toxicity and provides a better understanding of the biocompatibility of nanomaterials applied in human bone repair.

Divalent Metal Ions Induced Osteogenic Differentiation of MC3T3E1

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Wang, Guoshou; Su, Wenta; Chen, Pohung; Huang, Teyang

2017-12-01

Biomaterial scaffolds blended with biochemical signal molecules with adequate osteoinductive and osteoconductive properties have attracted significant interest in bone tissue engineering regeneration. The divalent metal ions can gradually release from the scaffold into the culture medium and then induced osteoblastic differentiation of MC3T3E1. These MC3T3E1 cells expressed high activity of alkaline phosphatase, bone-related gene expression of collagen type I, Runx2, osteopontin, osteocalcin, and significantly enhanced deposited minerals on scaffold after 21 days of culture. This experiment provided a useful inducer for osteogenic differentiation in bone repair.

Cuscuta chinensis seeds water extraction protecting murine osteoblastic MC3T3-E1 cells against tertiary butyl hydroperoxide induced injury.

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Gao, Jian-mei; Li, Ran; Zhang, Lei; Jia, Li-long; Ying, Xi-xiang; Dou, De-qiang; Li, Jian-chun; Li, Hai-bo

2013-07-09

Cuscuta chinensis (C. chinensis) is a well-known traditional Chinese herb that has been used to treat heart disease, diabetes, liver injury, cancer, and aging. Murine osteoblastic MC3T3-E1 cells were treated with various concentrations of C. chinensis water extraction at different time intervals. The antioxidant effect of C. chinensis on MC3T3-E1 cells was evaluated using MTT and TUNEL assays. The effect of C. chinensis on cell cycle was analyzed by flow cytometry with propidium iodide. Lipid peroxidation was measured by the HPLC method. The cellular redox status was determined from the reduced glutathione to oxidized glutathione ratio (GSH/GSSG) and the enzymes involved in glutathione metabolism, including glutathione reductase (GR), Glutathione S-transferase (GST), and Glucose-6-phosphate dehydrogenase (G6PD). The changes in relative mitochondrial transmembrane potential (ΔΨm) in the MC3T3-E1 cells were analyzed with rhodamine 123 staining. Western blot analysis was used to evaluate the levels of cytochrome c (cyto c), Bax, Bcl-2, caspase 3, Sirt3, and IDH2 expressions. The C. chinensis water extraction protects tertiary butyl hydroperoxide (TBHP)-treated MC3T3-E1 cells from death in a dose-dependent manner. C. chinensis treatment significantly inhibited the reactive oxygen species (ROS) generation, malondialdehyde (MDA) production, and increased the activity of superoxide dismutase (SOD), GR, GST, and G6PD. The release of cyto c from mitochondria was reduced by C. chinensis, which increased the expression of antiapoptotic IDH2, Sirt3, and Bcl-2 and decreased the expression of Bax, cyto c, and caspase 3. C. chinensis modulated the oxidative stress-induced apoptosis in MC3T3-E1 cells, probably due to its antioxidant activity and functioning via mitochondria-dependent pathways. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Graphene Oxide Hybridized nHAC/PLGA Scaffolds Facilitate the Proliferation of MC3T3-E1 Cells

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Liang, Chunyong; Luo, Yongchao; Yang, Guodong; Xia, Dan; Liu, Lei; Zhang, Xiaomin; Wang, Hongshui

2018-01-01

Biodegradable porous biomaterial scaffolds play a critical role in bone regeneration. In this study, the porous nano-hydroxyapatite/collagen/poly(lactic-co-glycolic acid)/graphene oxide (nHAC/PLGA/GO) composite scaffolds containing different amount of GO were fabricated by freeze-drying method. The results show that the synthesized scaffolds possess a three-dimensional porous structure. GO slightly improves the hydrophilicity of the scaffolds and reinforces their mechanical strength. Young's modulus of the 1.5 wt% GO incorporated scaffold is greatly increased compared to the control sample. The in vitro experiments show that the nHAC/PLGA/GO (1.5 wt%) scaffolds significantly cell adhesion and proliferation of osteoblast cells (MC3T3-E1). This present study indicates that the nHAC/PLGA/GO scaffolds have excellent cytocompatibility and bone regeneration ability, thus it has high potential to be used as scaffolds in the field of bone tissue engineering.

[The effects of platelet-rich fibrin extract on MC3T3-E1 cells cultured on the titanium discs].

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Zhang, X J; Xu, S; Meng, W Y; Xiao, H J; Dong, K; Liu, Z H

2017-01-09

Objective: To evaluate the effect of platelet-rich fibrin extract (PRFe) on the adhesion, proliferation and differentiation of MC3T3-E1 cells cultured on the titanium discs. Methods: Samples were divided into experimental group (P) and control group (D). Group P used the α-minimal essential medium (α-MEM) containing PRFe (0.5%), while group D used only the α-MEM. Cell adhesion and cytoskeleton were observed using scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM). Methyl thiazolyl tetrazolium (MTT) assay to detect the number of the osteoblasts at 1, 3, 5, 7 d; the activity of alkaline phosphatase (ALP) to detect the differentiation of osteoblast at 1, 3, 5, 7 d; the level of osteogenetic biomarkers core-binding factorα1 (cbfα1) and osteocalcin (OCN) were quantified by quantitative real-time PCR (qRT-PCR) at 3 and 7 d. Results: SEM and LSCM showed that the adhesion and filaments of group P were higher than those of group D at each time point. MTT assay showed that the absorbance were significantly increased in group P (1 d: 0.299±0.002, 3 d: 0.517±0.004, 5 d: 0.810±0.002, 7 d: 1.203±0.011) compared with group D (1 d: 0.198±0.003, 3 d: 0.399±0.002, 5 d: 0.588±0.002, 7 d: 0.897±0.005) at each time points ( P< 0.05). Furthermore, the ALP activity of group P (1 d: 0.162±0.004, 3 d: 0.289±0.001, 5 d: 0.491±0.006, 7 d: 0.647±0.005) was significantly higher than that of group D (1 d: 0.121±0.003, 3 d: 0.191± 0.006, 5 d: 0.252±0.004, 7 d: 0.365±0.012), ( P< 0.05). Moreover, the qRT-PCR showed that the Cbfα1 and OCN gene expression in group P (Cfbα1, 3 d: 1.50±0.04, 7 d: 1.94±0.06; OCN, 3 d: 3.37±0.17, 7 d: 3.92± 0.04) were significantly higher than that in group D(Cfbα1, 3 d: 1, 7 d: 1.18±0.13; OCN, 3 d: 1, 7 d: 2.34± 0.09) ( P< 0.05). Conclusions: PRFe promoted the adhension, proliferation and differentiation of MC3T3-E1 cells on the titanium discs.

Ginsenoside Re Promotes Osteoblast Differentiation in Mouse Osteoblast Precursor MC3T3-E1 Cells and a Zebrafish Model

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Hye-Min Kim

2016-12-01

Full Text Available Bone homeostasis is tightly regulated to balance bone formation and bone resorption. Many anabolic drugs are used as bone-targeted therapeutic agents for the promotion of osteoblast-mediated bone formation or inhibition of osteoclast-mediated bone resorption. Previous studies showed that ginsenoside Re has the effect of the suppression of osteoclast differentiation in mouse bone-marrow derived macrophages and zebrafish. Herein, we investigated whether ginsenoside Re affects osteoblast differentiation and mineralization in in vitro and in vivo models. Mouse osteoblast precursor MC3T3-E1 cells were used to investigate cell viability, alkaline phosphatase (ALP activity, and mineralization. In addition, we examined osteoblastic signaling pathways. Ginsenoside Re affected ALP activity without cytotoxicity, and we also observed the stimulation of osteoblast differentiation through the activation of osteoblast markers including runt-related transcription factor 2, type 1 collagen, ALP, and osteocalcin in MC3T3-E1 cells. Moreover, Alizarin red S staining indicated that ginsenoside Re increased osteoblast mineralization in MC3T3-E1 cells and zebrafish scales compared to controls. These results suggest that ginsenoside Re promotes osteoblast differentiation as well as inhibits osteoclast differentiation, and it could be a potential therapeutic agent for bone diseases.

Mechanotransductive Regulation of Gap-Junction Activity Between MLO-Y4 Osteocyte-Like and MC3T3-E1 Osteoblast-Like Cells in Three-Dimensional Co-Culture.

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Juran, C. M.; Blaber, E. A.; Almeida, E. A. C.

2016-01-01

Cell and animal studies conducted onboard the International Space Station and formerly on Shuttle flights have provided groundbreaking data illuminating the deleterious biological response of bone to mechanical unloading. However the intercellular communicative mechanisms associated with the regulation of bone synthesis and bone resorption cells are still largely unknown. Connexin-43 (CX43), a gap junction protein, is hypothesized to play a significant role in osteoblast and osteocyte signaling. The purpose of this investigation was to evaluate within a novel three-dimensional microenvironment how the osteocyte-osteoblast gap-junction expression changes when cultures are exposed to exaggerated mechanical load. MLO-Y4 osteocyte-like cells were cultured on a 3D-Biotek polystyrene insert and placed in direct contact with an MC3T3-E1 pre-osteoblast co-cultured monolayer and exposed to 48 h of mechanical stimulation (pulsatile fluid flow (PFF) or monolayer cyclic stretch (MCS)) then evaluated for viability, proliferation, metabolism, and CX43 expression. Mono-cultured MLO-Y4 and MC3T3-E1 control experiments were conducted under PFF and MCS stimulation to observe how strain application stimuli (PFF cell membrane shear or MCS cell focal adhesion/attachment loading) initiates different signaling pathways or downstream regulatory controls. TotalLive cell count, viability and metabolic reduction (Trypan Blue, LIVEDead and Alamar Blue analysis respectively) indicate that mechanical activation of MC3T3-E1 cells inhibits proliferation while maintaining an average 1.04E4 reductioncell metabolic rate, *p0.05 n4. MLO-Y4s in monolayer culture increase in number when exposed to MCS loading but the percent of live cells within the population is low (46.3 total count, *p0.05 n4), these results may indicate an apoptotic signaling cascade. PFF stimulation of the three-dimensional co-cultures elicits a universal increase in CX43 in MLO-Y4 and MC3T3-E1 cells, illustrated by

Linarin isolated from Buddleja officinalis prevents hydrogen peroxide-induced dysfunction in osteoblastic MC3T3-E1 cells.

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Kim, Young Ho; Lee, Young Soon; Choi, Eun Mi

2011-01-01

The flowers and leaves buds of Buddleja officinalis MAXIM (Buddlejaceae) are used to treat eye troubles, hernia, gonorrhea and liver troubles in Asia. To elucidate the protective effects of linarin isolated from B. officinalis on the response of osteoblast to oxidative stress, osteoblastic MC3T3-E1 cells were pre-incubated with linarin for 1h before treatment with 0.3mM H(2)O(2) for 48h, and markers of osteoblast function and oxidative damage were examined. Linarin significantly (P<0.05) increased cell survival, alkaline phosphatase (ALP) activity, collagen content, calcium deposition, and osteocalcin secretion and decreased the production of receptor activator of nuclear factor-kB ligand (RANKL), protein carbonyl (PCO), and malondialdehyde (MDA) of osteoblastic MC3T3-E1 cells in the presence of hydrogen peroxide. These results demonstrate that linarin can protect osteoblasts against hydrogen peroxide-induced osteoblastic dysfunction and may exert anti-resorptive actions, at least in part, via the reduction of RANKL and oxidative damage. 2011 Elsevier Inc. All rights reserved.

Low-intensity pulsed ultrasound (LIPUS) stimulates mineralization of MC3T3-E1 cells through calcium and phosphate uptake.

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Tassinary, João Alberto Fioravante; Lunardelli, Adroaldo; Basso, Bruno de Souza; Dias, Henrique Bregolin; Catarina, Anderson Velasque; Stülp, Simone; Haute, Gabriela Viegas; Martha, Bianca Andrade; Melo, Denizar Alberto da Silva; Nunes, Fernanda Bordignon; Donadio, Márcio Vinícius Fagundes; Oliveira, Jarbas Rodrigues de

2018-03-01

The present study aimed to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on pre-osteoblast mineralization using in vitro bioassays. Pre-osteoblastic MC3T3-E1 cells were exposed to LIPUS at 1 MHz frequency, 0.2 W/cm 2 intensity and 20% duty cycle for 30 min. The analyses were carried out up to 336 h (14 days) after exposure. The concentration of collagen, phosphate, alkaline phosphatase, calcium and transforming growth factor beta 1 (TGF-β1) in cell supernatant and the presence of calcium deposits in the cells were analyzed. Our results showed that LIPUS promotes mineralized nodules formation. Collagen, phosphate, and calcium levels were decreased in cell supernatant at 192 h after LIPUS exposure. However, alkaline phosphatase and TGF-β1 concentrations remained unchanged. Therapeutic pulsed ultrasound is capable of stimulating differentiation and mineralization of pre-osteoblastic MC3T3-E1 cells by calcium and phosphate uptake with consequent hydroxyapatite formation. Copyright © 2017 Elsevier B.V. All rights reserved.

7-ketocholesterol induces apoptosis of MC3T3-E1 cells associated with reactive oxygen species generation, endoplasmic reticulum stress and caspase-3/7 dependent pathway

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Yuta Sato

2017-03-01

Full Text Available Type 2 diabetes mellitus (T2DM is associated with an increased risk of bone fractures without reduction of bone mineral density. The cholesterol oxide 7-ketocholesterol (7KCHO has been implicated in numerous diseases such as atherosclerosis, Alzheimer's disease, Parkinson's disease, cancer, age-related macular degeneration and T2DM. In the present study, 7KCHO decreased the viability of MC3T3-E1 cells, increased reactive oxygen species (ROS production and apoptotic rate, and upregulated the caspase-3/7 pathway. Furthermore, these effects of 7KCHO were abolished by pre-incubation of the cells with N-acetylcysteine (NAC, an ROS inhibitor. Also, 7KCHO enhanced the mRNA expression of two endoplasmic reticulum (ER stress markers; CHOP and GRP78, in MC3T3-E1 cells. Pre-incubation of the cells with NAC suppressed the 7KCHO-induced upregulation of CHOP, but not GRP78. In conclusion, we demonstrated that 7KCHO induced apoptosis of MC3T3-E1 cells associated with ROS generation, ER stress, and caspase-3/7 activity, and the effects of 7KCHO were abolished by the ROS inhibitor NAC. These findings may provide new insight into the relationship between oxysterol and pathophysiology of osteoporosis seen in T2DM.

The role of non-thermal atmospheric pressure biocompatible plasma in the differentiation of osteoblastic precursor cells, MC3T3-E1.

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Han, Ihn; Choi, Eun Ha

2017-05-30

Non-thermal atmospheric pressure plasma is ionized matter, composed of highly reactive species that include positive ions, negative ions, free radicals, neutral atoms, and molecules. Recent reports have suggested that non-thermal biocompatible plasma (NBP) can selectively kill a variety of cancer cells, and promote stem cell differentiation. However as of yet, the regulation of proliferation and differentiation potential of NBP has been poorly understood.Here, we investigated the effects of NBP on the osteogenic differentiation of precursor cell lines of osteoblasts, MC3T3 E1 and SaOS-2. For in vitro osteogenic differentiation, precursor cell lines were treated with NBP, and cultured with osteogenic induction medium. After 10 days of treatment, the NBP was shown to be effective in osteogenic differentiation in MC3T3 E1 cells by von Kossa and Alizarin Red S staining assay. Real-time PCR was then performed to investigate the expression of osteogenic specific genes, Runx2, OCN, COL1, ALP and osterix in MC3T3 E1 cells after treatment with NBP for 4 days. Furthermore, analysis of the protein expression showed that NBP treatment significantly reduced PI3K/AKT signaling and MAPK family signaling. However, p38 controlled phosphorylation of transcription factor forkhead box O1 (FoxO1) that related to cell differentiation with increased phosphorylated p38. These results suggest that non-thermal atmospheric pressure plasma can induce osteogenic differentiation, and enhance bone formation.

Osteogenic differentiation of MC3T3-E1 cells on poly(L-lactide)/Fe{sub 3}O{sub 4} nanofibers with static magnetic field exposure

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Cai, Qing [State Key Laboratory of Organic–inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029 (China); Shi, Yuzhou; Shan, Dingying; Jia, Wenkai; Duan, Shun [Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029 (China); Deng, Xuliang [Department of Geriatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081 (China); Yang, Xiaoping, E-mail: yangxp@mail.buct.edu.cn [State Key Laboratory of Organic–inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029 (China)

2015-10-01

Proliferation and differentiation of bone-related cells are modulated by many factors such as scaffold design, growth factor, dynamic culture system, and physical simulation. Nanofibrous structure and moderate-intensity (1 mT–1 T) static magnetic field (SMF) have been identified as capable of stimulating proliferation and differentiation of osteoblasts. Herein, magnetic nanofibers were prepared by electrospinning mixture solutions of poly(L-lactide) (PLLA) and ferromagnetic Fe{sub 3}O{sub 4} nanoparticles (NPs). The PLLA/Fe{sub 3}O{sub 4} composite nanofibers demonstrated homogeneous dispersion of Fe{sub 3}O{sub 4} NPs, and their magnetism depended on the contents of Fe{sub 3}O{sub 4} NPs. SMF of 100 mT was applied in the culture of MC3T3-E1 osteoblasts on pure PLLA and PLLA/Fe{sub 3}O{sub 4} composite nanofibers for the purpose of studying the effect of SMF on osteogenic differentiation of osteoblastic cells on magnetic nanofibrous scaffolds. On non-magnetic PLLA nanofibers, the application of external SMF could enhance the proliferation and osteogenic differentiation of MC3T3-E1 cells. In comparison with pure PLLA nanofibers, the incorporation of Fe{sub 3}O{sub 4} NPs could also promote the proliferation and osteogenic differentiation of MC3T3-E1 cells in the absence or presence of external SMF. The marriage of magnetic nanofibers and external SMF was found most effective in accelerating every aspect of biological behaviors of MC3T3-E1 osteoblasts. The findings demonstrated that the magnetic feature of substrate and microenvironment were applicable ways in regulating osteogenesis in bone tissue engineering. - Highlights: • Magnetic nanofibers containing well-dispersed Fe{sub 3}O{sub 4} nanoparticles were produced. • Static magnetic field (SMF) was applied to perform the culture of osteoblasts. • Osteogenic differentiation was enhanced on magnetic substrate with exposure to SMF.

Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells

International Nuclear Information System (INIS)

Qu, Bo; Ma, Yuan; Yan, Ming; Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui; Pan, Xianming

2016-01-01

Osteoporosis is a skeletal disorder characterized by bone loss, resulting in architectural deterioration of the skeleton, decreased bone strength and an increased risk of fragility fractures. Strengthening osteogenesis is an effective way to relieve osteoporosis. Sirtuin1 (Sirt1) is a nicotinamide adenine dinucleotide (NAD"+)-dependent deacetylase, which is reported to be involved in improving osteogenesis. Sirt1 targets peroxisome proliferator-activated receptor γ (PPARγ) in the regulation of adipose tissues; however, the molecular mechanism of Sirt1 in osteogenic differentiation is still unknown. PPARγ tends to induce more adipogenic differentiation rather than osteogenic differentiation. Hence, we hypothesized that Sirt1 facilitates osteogenic differentiation through downregulation of PPARγ signaling. Mouse pre-osteoblastic MC3T3-E1 cells were cultured under osteogenic medium. Sirt1 was overexpressed through plasmid transfection. The results showed that high expression of Sirt1 was associated with increased osteogenic differentiation, as indicated by quantitative PCR and Western blot analysis of osteogenic markers, and Von Kossa staining. Sirt1 overexpression also directly and negatively regulated the expression of PPARγ and its downstream molecules. Use of the PPARγ agonist Rosiglitazone, reversed the effects of Sirt1 on osteogenic differentiation. Using constructed luciferase plasmids, we demonstrated a role of Sirt1 in inhibiting PPARγ–induced activity and expression of adipocyte–specific genes, including acetyl-coenzyme A carboxylase (Acc) and fatty acid binding protein 4 (Fabp4). The interaction between Sirt1 and PPARγ was further confirmed using co-immunoprecipitation analysis. Together, these results reveal a novel mechanism for Sirt1 in osteogenic differentiation through downregulation of PPARγ activity. These findings suggest that the Sirt1–PPARγ pathway may represent a potential target for enhancement of osteogenesis and treatment of

Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells

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Qu, Bo [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Ma, Yuan [Department of Neurosurgery, Chengdu Military General Hospital, Chengdu 610083 (China); Yan, Ming [Department of Orthopaedics, Xijing Hospital of The Fourth Military Medical University, Xi’an 710032 (China); Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Pan, Xianming, E-mail: xianmingpanxj@163.com [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China)

2016-09-09

Osteoporosis is a skeletal disorder characterized by bone loss, resulting in architectural deterioration of the skeleton, decreased bone strength and an increased risk of fragility fractures. Strengthening osteogenesis is an effective way to relieve osteoporosis. Sirtuin1 (Sirt1) is a nicotinamide adenine dinucleotide (NAD{sup +})-dependent deacetylase, which is reported to be involved in improving osteogenesis. Sirt1 targets peroxisome proliferator-activated receptor γ (PPARγ) in the regulation of adipose tissues; however, the molecular mechanism of Sirt1 in osteogenic differentiation is still unknown. PPARγ tends to induce more adipogenic differentiation rather than osteogenic differentiation. Hence, we hypothesized that Sirt1 facilitates osteogenic differentiation through downregulation of PPARγ signaling. Mouse pre-osteoblastic MC3T3-E1 cells were cultured under osteogenic medium. Sirt1 was overexpressed through plasmid transfection. The results showed that high expression of Sirt1 was associated with increased osteogenic differentiation, as indicated by quantitative PCR and Western blot analysis of osteogenic markers, and Von Kossa staining. Sirt1 overexpression also directly and negatively regulated the expression of PPARγ and its downstream molecules. Use of the PPARγ agonist Rosiglitazone, reversed the effects of Sirt1 on osteogenic differentiation. Using constructed luciferase plasmids, we demonstrated a role of Sirt1 in inhibiting PPARγ–induced activity and expression of adipocyte–specific genes, including acetyl-coenzyme A carboxylase (Acc) and fatty acid binding protein 4 (Fabp4). The interaction between Sirt1 and PPARγ was further confirmed using co-immunoprecipitation analysis. Together, these results reveal a novel mechanism for Sirt1 in osteogenic differentiation through downregulation of PPARγ activity. These findings suggest that the Sirt1–PPARγ pathway may represent a potential target for enhancement of osteogenesis and treatment

MC3T3-E1 cell response of amorphous phase/TiO{sub 2} nanocrystal composite coating prepared by microarc oxidation on titanium

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Zhou, Rui [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wei, Daqing, E-mail: daqingwei@hit.edu.cn [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yang, Haoyue; Feng, Wei [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Cheng, Su [Department of Mechanical Engineering, School of Architecture and Civil Engineering, Harbin University of Science and Technology, Harbin 150001 (China); Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

2014-06-01

Bioactive amorphous phase/TiO{sub 2} nanocrystal (APTN) composite coatings were fabricated by microarc oxidation (MAO) on Ti. The APTN coatings are composed of much amorphous phase with Si, Na, Ca, Ti and O elements and a few TiO{sub 2} nanocrystals. With increasing applied voltage, the micropore density of the APTN coating decreases and the micropore size of the APTN coating increases. The results indicate that less MC3T3-E1 cells attach on the APTN coatings as compared to Ti. However, the APTN coatings greatly enhance the cell proliferation ability and the activity of alkaline phosphatase. The amorphous phase and the concentrations of the released Ca and Si from the APTN coatings during cell culture have significant effects on the cell response. - Highlights: • Amorphous phase/TiO2 nanocrystal (APTN) composite coatings were fabricated. • The MC3T3-E1 cell response of the APTN coatings was evaluated. • The APTN coatings greatly enhanced the cell proliferation ability.

Effects of irradiation on TGF-β1 mRNA expression and calcific nodule formation in MC3T3-E1 osteoblastic cell line

International Nuclear Information System (INIS)

Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon

2008-01-01

To investigate the effects of irradiation on transforming growth factor β1 (TGF-β 1 ) mRNA expression and calcific nodule formation in MC3T3-E1 osteoblastic cell line. Cells were cultured in alpha-minimum essential medium (α-MEM) supplemented with 10% fetal bovine serum and antibiotics. When the cells reached the level of 70-80% confluence, culture media were changed with α-MEM supplemented with 10% FBS, 5 mM β-glycerol phosphate, and 50 μg/mL ascorbic acid. Thereafter the cells were irradiated with a single dose of 2, 4, 6, 8 Gy at a dose rate of 1.5 Gy/min. The expression pattern of TGF-β 1 mRNA, calcium content and calcific nodule formation were examined on day 3, 7, 14, 21, 28, respectively, after the irradiation. The amount of TGF-β 1 mRNA expression decreased significantly on day 7 after irradiation of 4, 6, 8 Gy. It also decreased on day 14 after irradiation of 6, 8 Gy, and decreased on day 21 after irradiation of 8 Gy. The amount of calcium deposition decreased significantly on day 7 after irradiation of 4, 8 Gy (P 1 mRNA expression that was associated with proliferation and the production of extracellular matrix in MC3T3-E1 osteoblastic cell line

Protection by the flavonoids quercetin and luteolin against peroxide- or menadione-induced oxidative stress in MC3T3-E1 osteoblast cells.

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Fatokun, Amos A; Tome, Mercedes; Smith, Robert A; Darlington, L Gail; Stone, Trevor W

2015-01-01

Potential protective effects of the flavonoids quercetin and luteolin have been examined against the oxidative stress of MC3T3-E1 osteoblast-like cells. Although hydrogen peroxide and menadione reduced cell viability, the toxicity was prevented by desferrioxamine or catalase but not superoxide dismutase, suggesting the involvement of hydrogen peroxide in both cases. Quercetin and luteolin reduced the oxidative damage, especially that caused by hydrogen peroxide. When cultures were pre-incubated with quercetin or luteolin, protection was reduced or lost. Protection was also reduced when a 24 h pre-incubation with the flavonoids was followed by exposure to menadione alone. Pretreating cultures with luteolin impaired protection by quercetin, whereas quercetin pretreatment did not affect protection by luteolin. It is concluded that quercetin and luteolin suppress oxidative damage to MC3T3-E1 cells, especially caused by peroxide. The reduction in protection by pretreatment implies a down-regulation of part of the toxic transduction pathway.

Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

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Yamauchi Mika

2007-11-01

Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

Inhibition of microRNA-214-5p promotes cell survival and extracellular matrix formation by targeting collagen type IV alpha 1 in osteoblastic MC3T3-E1 cells.

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Li, Q S; Meng, F Y; Zhao, Y H; Jin, C L; Tian, J; Yi, X J

2017-08-01

This study aimed to investigate the functional effects of microRNA (miR)-214-5p on osteoblastic cells, which might provide a potential role of miR-214-5p in bone fracture healing. Blood samples were obtained from patients with hand fracture or intra-articular calcaneal fracture and from healthy controls (HCs). Expression of miR-214-5p was monitored by qRT-PCR at day 7, 14 and 21 post-surgery. Mouse osteoblastic MC3T3-E1 cells were transfected with antisense oligonucleotides (ASO)-miR-214-5p, collagen type IV alpha 1 (COL4A1) vector or their controls; thereafter, cell viability, apoptotic rate, and the expression of collagen type I alpha 1 (COL1A1), type II collagen (COL-II), and type X collagen (COL-X) were determined. Luciferase reporter assay, qRT-PCR, and Western blot were performed to ascertain whether COL4A1 was a target of miR-214-5p. Plasma miR-214-5p was highly expressed in patients with bone fracture compared with HCs after fracture (p extracellular matrix (ECM) formation of osteoblastic MC3T3-E1 cells by targeting COL4A1. Cite this article: Q. S. Li, F. Y. Meng, Y. H. Zhao, C. L. Jin, J. Tian, X. J. Yi. Inhibition of microRNA-214-5p promotes cell survival and extracellular matrix formation by targeting collagen type IV alpha 1 in osteoblastic MC3T3-E1 cells. Bone Joint Res 2017;6:464-471. DOI: 10.1302/2046-3758.68.BJR-2016-0208.R2. © 2017 Yi et al.

Oscillatory fluid flow elicits changes in morphology, cytoskeleton and integrin-associated molecules in MLO-Y4 cells, but not in MC3T3-E1 cells

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Huiyun Xu

2012-01-01

Full Text Available Interstitial fluid flow stress is one of the most important mechanical stimulations of bone cells under physiological conditions. Osteocytes and osteoblasts act as primary mechanosensors within bones, and in vitro are able to respond to fluid shear stress, both morphologically and functionally. However, there is little information about the response of integrin-associated molecules using both osteoblasts and osteocytes. In this study, we investigated the changes in response to 2 hours of oscillatory fluid flow stress in the MLO-Y4 osteocyte-like cell line and the MC3T3-E1 osteoblast-like cell line. MLO-Y4 cells exhibited a significant increase in the expression of integrin-associated molecules, including OPN, CD44, vinculin and integrin avp3. However, there was no or limited increase observed in MC3T3-E1 osteoblast-like cells. Cell area and fiber stress formation were also markedly promoted by fluid flow only in MLO-Y4 cells. But the numbers of processes per cell remain unaffected in both cell lines.

[Effect of NF-κB on the expression of interleukin-6 induced by lipopolysaccharides of Porphyromonas endodontalis in MC3T3-E1 cells].

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Yu, Ya-qiong; Guo, Jia-jie; Qiu, Li-hong; Lv, You; Jia, Ge; Guo, Yan

2013-08-01

To investigate the effect of NF-κB signaling on the expression of interleukin-6(IL-6) induced by lipopolysaccharides(LPS) extracted from Porphyromonas endodontalis(P.e) in MC3T3-El cells. MC3T3-E1 cells were pretreated with BAY-117082 for 1 h, and then were treated with 10 mg/L P.e-LPS for different times. The translocation of NF-κB was observed by immunofluorescence. The expression of IL-6 was detected by reverse transcription polymerse chain reaction (RT-PCR) and enzyme-linked immuno sorbent assay (ELISA). Statistical analysis was performed using multi-way ANOVA and Dunnett's t test with SPSS 13.0 software package. The staining of NF-κB was mostly in cytoplasm in untreated cells. Rapid translocation of NF-κB into nucleus was observed in the cells stimulated for 30 min and mostly relocalization of NF-κB from nucleus to cytoplasm was observed after 60 min. Pretreatment with 10 μmol/L BAY-117082 for 1h significantly inhibited P.e-LPS-induced translocation of NF-κB .The mRNA and proteins of IL-6 decreased significantly after pretreatment with 10 μmol/L BAY-117082 and the expression of IL-6 proteins was reduced from (774.983±6.585) ng/L to (377.384±14.620) ng/L (P<0.01). The group of treatment with BAY-117082 alone had no significant difference from the blank control group. P.e-LPS can induce translocation of NF-κB in mouse osteoblast MC3T3-El, and P.e-LPS may induce the expression of IL-6 in mouse osteoblast through the signaling of NF-κB.

Bone morphogenetic protein-2 (BMP-2 and transforming growth factor-β1 (TGF-β1 alter connexin 43 phosphorylation in MC3T3-E1 Cells

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Rudkin George H

2001-07-01

Full Text Available Abstract Background Bone morphogenetic proteins (BMPs and transforming growth factor-βs (TGF-βs are important regulators of bone repair and regeneration. BMP-2 and TGF-β1 have been shown to inhibit gap junctional intercellular communication (GJIC in MC3T3-E1 cells. Connexin 43 (Cx43 has been shown to mediate GJIC in osteoblasts and it is the predominant gap junctional protein expressed in these murine osteoblast-like cells. We examined the expression, phosphorylation, and subcellular localization of Cx43 after treatment with BMP-2 or TGF-β1 to investigate a possible mechanism for the inhibition of GJIC. Results Northern blot analysis revealed no detectable change in the expression of Cx43 mRNA. Western blot analysis demonstrated no significant change in the expression of total Cx43 protein. However, significantly higher ratios of unphosphorylated vs. phosphorylated forms of Cx43 were detected after BMP-2 or TGF-β1 treatment. Immunofluorescence and cell protein fractionation revealed no detectable change in the localization of Cx43 between the cytosol and plasma membrane. Conclusions BMP-2 and TGF-β1 do not alter expression of Cx43 at the mRNA or protein level. BMP-2 and TGF-β1 may inhibit GJIC by decreasing the phosphorylated form of Cx43 in MC3T3-E1 cells.

Genes Responsive to Low-Intensity Pulsed Ultrasound in MC3T3-E1 Preosteoblast Cells

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Yoshiaki Tabuchi

2013-11-01

Full Text Available Although low-intensity pulsed ultrasound (LIPUS has been shown to enhance bone fracture healing, the underlying mechanism of LIPUS remains to be fully elucidated. Here, to better understand the molecular mechanism underlying cellular responses to LIPUS, we investigated gene expression profiles in mouse MC3T3-E1 preosteoblast cells exposed to LIPUS using high-density oligonucleotide microarrays and computational gene expression analysis tools. Although treatment of the cells with a single 20-min LIPUS (1.5 MHz, 30 mW/cm2 did not affect the cell growth or alkaline phosphatase activity, the treatment significantly increased the mRNA level of Bglap. Microarray analysis demonstrated that 38 genes were upregulated and 37 genes were downregulated by 1.5-fold or more in the cells at 24-h post-treatment. Ingenuity pathway analysis demonstrated that the gene network U (up contained many upregulated genes that were mainly associated with bone morphology in the category of biological functions of skeletal and muscular system development and function. Moreover, the biological function of the gene network D (down, which contained downregulated genes, was associated with gene expression, the cell cycle and connective tissue development and function. These results should help to further clarify the molecular basis of the mechanisms of the LIPUS response in osteoblast cells.

CSN1S2 protein of goat milk inhibits the decrease of viability and increases the proliferation of MC3T3E1 pre-osteoblast cell in methyl glyoxal exposure

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Choirunil Chotimah

2015-03-01

Full Text Available Objective: To investigate whether the CNS1S2 protein of goat milk is able to inhibit the toxicity of methyl glyoxal (MG towards MC3T3E1 pre-osteoblast cells. Methods: At confluency, pre-osteoblast cells were divided into five groups which included control (untreated, pre-osteoblast cells exposed to 5 µmol/L MG, pre-osteoblast cells exposed to MG in the presence of CSN1S2 protein at doses of 0.025, 0.050, and 0.100 mg/L, respectively. Analysis of reactive oxygen species was done with 2,7-dichlorodihydrofluorescein diacetate fluorochrome. The proliferation and viability of MC3T3E1 cells were measured by trypan blue staining. Malondialdehyde analysis was done colorimetrically. Results: Cell's viabilities were significantly lower in MG+0.050 mg/L CSN1S2 protein of goat milk compared to MG group (P<0.05. MG+0.100 mg/L CSN1S2 protein of goat milk significantly increased the cells viability compared to MG group (P<0.05. The levels of proliferation were significantly higher in MG+0.100 mg/L CSN1S2 protein of goat milk compared to control group and all treatment groups, respectively (P<0.05. Conclusions: High dose of CSN1S2 protein of goat milk (0.100 mg/L in high MG environment inhibits the decrease of viability due to the increases of the proliferation of MC3T3E1 preosteoblast cell.

Poly(acrylic acid-regulated Synthesis of Rod-Like Calcium Carbonate Nanoparticles for Inducing the Osteogenic Differentiation of MC3T3-E1 Cells

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Wei Yang

2016-05-01

Full Text Available Calcium carbonate, especially with nanostructure, has been considered as a good candidate material for bone regeneration due to its excellent biodegradability and osteoconductivity. In this study, rod-like calcium carbonate nanoparticles (Rod-CC NPs with desired water dispersibility were achieved with the regulation of poly (acrylic acid. Characterization results revealed that the Rod-CC NPs had an average length of 240 nm, a width of 90 nm with an average aspect ratio of 2.60 and a negative ζ-potential of −22.25 ± 0.35 mV. The degradation study illustrated the nanoparticles degraded 23% at pH 7.4 and 45% at pH 5.6 in phosphate-buffered saline (PBS solution within three months. When cultured with MC3T3-E1 cells, the Rod-CC NPs exhibited a positive effect on the proliferation of osteoblast cells. Alkaline phosphatase (ALP activity assays together with the osteocalcin (OCN and bone sialoprotein (BSP expression observations demonstrated the nanoparticles could induce the differentiation of MC3T3-E1 cells. Our study developed well-dispersed rod-like calcium carbonate nanoparticles which have great potential to be used in bone regeneration.

Cytotoxicity of Titanate-Calcium Complexes to MC3T3 Osteoblast-Like Cells

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Drury, Jeanie L.; Moussi, Joelle; Taylor-Pashow, Kathryn M. L.

2016-01-01

Monosodium titanates (MST) are a relatively novel form of particulate titanium dioxide that have been proposed for biological use as metal sorbents or delivery agents, most recently calcium (II). In these roles, the toxicity of the titanate or its metal complex is crucial to its biological utility. The aim of this study was to determine the cytotoxicity of MST and MST-calcium complexes with MC3T3 osteoblast-like cells; MST-Ca(II) complexes could be useful to promote bone formation in various hard tissue applications. MC3T3 cells were exposed to native MST or MST-Ca(II) complexes for 24–72 h. A CellTiter-Blue® assay was employed to assess the metabolic activity of the cells. The results showed that MST and MST-Ca(II) suppressed MC3T3 metabolic activity significantly in a dose-, time-, and cell-density-dependent fashion. MST-Ca(II) suppressed MC3T3 metabolism in a statistically identical manner as native MST at all concentrations. We concluded that MST and MST-Ca(II) are significantly cytotoxic to MC3T3 cells through a mechanism yet unknown; this is a potential problem to the biological utility of these complexes. PMID:28044136

Cytotoxicity of Titanate-Calcium Complexes to MC3T3 Osteoblast-Like Cells

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Yen-Wei Chen

2016-01-01

Full Text Available Monosodium titanates (MST are a relatively novel form of particulate titanium dioxide that have been proposed for biological use as metal sorbents or delivery agents, most recently calcium (II. In these roles, the toxicity of the titanate or its metal complex is crucial to its biological utility. The aim of this study was to determine the cytotoxicity of MST and MST-calcium complexes with MC3T3 osteoblast-like cells; MST-Ca(II complexes could be useful to promote bone formation in various hard tissue applications. MC3T3 cells were exposed to native MST or MST-Ca(II complexes for 24–72 h. A CellTiter-Blue® assay was employed to assess the metabolic activity of the cells. The results showed that MST and MST-Ca(II suppressed MC3T3 metabolic activity significantly in a dose-, time-, and cell-density-dependent fashion. MST-Ca(II suppressed MC3T3 metabolism in a statistically identical manner as native MST at all concentrations. We concluded that MST and MST-Ca(II are significantly cytotoxic to MC3T3 cells through a mechanism yet unknown; this is a potential problem to the biological utility of these complexes.

Influence of MC3T3-E1 preosteoblast culture on the corrosion of a T6-treated AZ91 alloy

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Brooks, Emily K.; Tobias, Menachem E.; Yang, Shuying; Bone, Lawrence B.; Ehrensberger, Mark T.

2015-01-01

This study investigated the corrosion of artificially aged T6 heat-treated Mg-9%Al-1%Zn (AZ91) for biomedical applications. Corrosion tests and surface analysis were completed both with and without a monolayer of mouse preosteoblast MC3T3-E1 cells cultured on the sample. Electrochemical impedance spectroscopy (EIS) and inductively coupled plasma mass spectroscopy (ICPMS) were used to explore the corrosion processes after either 3 or 21 days of AZ91 incubation in cell culture medium (CCM). The EIS showed both the inner layer resistance (Rin) and outer layer resistance (Rout) were lower for samples without cells cultured on the surface at 3 days (Rin = 2.64 e4 Ω/cm2, Rout = 140 Ω/cm2) compared to 21 days (Rin = 3.60 e4 Ω/cm2, Rout = 287 Ω/cm2) due to precipitation of magnesium and calcium phosphates over time. Samples with preosteoblasts cultured on the surface had a slower initial corrosion (3 day, Rin = 1.88 e5 Ω/cm2, Rout = 1060 Ω/cm2) which was observed to increase over time (21 day, Rin = 2.99 e4 Ω/cm2, Rout = 287 Ω/cm2). Changes in the corrosion processes were thought to be related to changes in the coverage provided by the cell layer. Our results reveal that the presence of cells and biological processes are able to significantly influence the corrosion rate of AZ91. PMID:25715925

Effect of acetaminophen on osteoblastic differentiation and migration of MC3T3-E1 cells.

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Nakatsu, Yoshihiro; Nakagawa, Fumio; Higashi, Sen; Ohsumi, Tomoko; Shiiba, Shunji; Watanabe, Seiji; Takeuchi, Hiroshi

2018-02-01

N-acetyl-p-aminophenol (APAP, acetaminophen, paracetamol) is a widely used analgesic/antipyretic with weak inhibitory effects on cyclooxygenase (COX) compared to non-steroidal anti-inflammatory drugs (NSAIDs). The mechanism of action of APAP is mediated by its metabolite that activates transient receptor potential channels, including transient receptor potential vanilloid 1 (TRPV1) and TRP ankyrin 1 (TRPA1) or the cannabinoid receptor type 1 (CB1). However, the exact molecular mechanism and target underlying the cellular actions of APAP remain unclear. Therefore, we investigated the effect of APAP on osteoblastic differentiation and cell migration, with a particular focus on TRP channels and CB1. Effects of APAP on osteoblastic differentiation and cell migration of MC3T3-E1, a mouse pre-osteoblast cell line, were assessed by the increase in alkaline phosphatase (ALP) activity, and both wound-healing and transwell-migration assays, respectively. APAP dose-dependently inhibited osteoblastic differentiation, which was well correlated with the effects on COX activity compared with other NSAIDs. In contrast, cell migration was promoted by APAP, and this effect was not correlated with COX inhibition. None of the agonists or antagonists of TRP channels and the CB receptor affected the APAP-induced cell migration, while the effect of APAP on cell migration was abolished by down-regulating TRPV4 gene expression. APAP inhibited osteoblastic differentiation via COX inactivation while it promoted cell migration independently of previously known targets such as COX, TRPV1, TRPA1 channels, and CB receptors, but through the mechanism involving TRPV4. APAP may have still unidentified molecular targets that modify cellular functions. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

The effects of low dose X-irradiation on osteoblastic MC3T3-E1 cells in vitro

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Xu Wei

2012-06-01

Full Text Available Abstract Background It has been indicated that moderate or high dose of X-irradiation could delay fracture union and cause osteoradionecrosis, in part, mediated by its effect on proliferation and differentiation of osteoblasts. However, whether low dose irradiation (LDI has similar roles on osteoblasts is still unknown. In this study, we investigated whether and to what extent LDI could affect the proliferation, differentiation and mineralization of osteoblasts in vitro. Methods The MC3T3-E1 cells were exposed to single dose of X-irradiation with 0, 0.1, 0.5, 1.0 Gy respectively. Cell proliferation, apoptosis, alkaline phosphatase (ALP activity, and mineralization was evaluated by methylthiazoletetrazolium (MTT and bromodeoxyuridine (BrdU assay, flow cytometry, ALP viability kit and von Kossa staining, respectively. Osteocalcin (OCN and core-binding factor α1 (Cbfα1 expressions were measured by real time-PCR and western blot, respectively. Results The proliferation of the cells exposed to 2.0 Gy was significantly lower than those exposed to ≤1.0 Gy (p  Conclusions LDI have different effects on proliferation and differentiation of osteoblasts from those of high dose of X-irradiation, which might suggest that LDI could lead to promotion of frature healing through enhancing the differentiation and mineralization of osteoblasts.

Influence of MC3T3-E1 preosteoblast culture on the corrosion of a T6-treated AZ91 alloy.

Science.gov (United States)

Brooks, Emily K; Tobias, Menachem E; Yang, Shuying; Bone, Lawrence B; Ehrensberger, Mark T

2016-02-01

This study investigated the corrosion of artificially aged T6 heat-treated Mg-9%Al-1%Zn (AZ91) for biomedical applications. Corrosion tests and surface analysis were completed both with and without a monolayer of mouse preosteoblast MC3T3-E1 cells cultured on the sample. Electrochemical impedance spectroscopy (EIS) and inductively coupled plasma mass spectroscopy (ICPMS) were used to explore the corrosion processes after either 3 or 21 days of AZ91 incubation in cell culture medium (CCM). The EIS showed both the inner layer resistance (Rin ) and outer layer resistance (Rout ) were lower for samples without cells cultured on the surface at 3 days (Rin  = 2.64 e4 Ω/cm(2) , Rout  = 140 Ω/cm(2) ) compared to 21 days (Rin  = 3.60 e4 Ω/cm(2) , Rout  = 287 Ω/cm(2) ) due to precipitation of magnesium and calcium phosphates over time. Samples with preosteoblasts cultured on the surface had a slower initial corrosion (3 day, Rin  = 1.88 e5 Ω/cm(2) , Rout  = 1060 Ω/cm(2) ) which was observed to increase over time (21 day, Rin  = 2.99 e4 Ω/cm(2) , Rout  = 287 Ω/cm(2) ). Changes in the corrosion processes were thought to be related to changes in the coverage provided by the cell layer. Our results reveal that the presence of cells and biological processes are able to significantly influence the corrosion rate of AZ91. © 2015 Wiley Periodicals, Inc.

Effects of 2-deoxy-D-glucose and quercetin on the expression of osteonectin and osteopontin during the differentiation of irradiated MC3T3-E1 osteoblastic cells

International Nuclear Information System (INIS)

Yu, Su Kyung; Koh, Kwang Joon; Kim, Kyoung A

2008-01-01

To characterize the effects of 2-deoxy-D-glucose (2-DG) and quercetin (QCT) on gene expression of osteonectin (ON) and osteopontin (OP) in irradiated MC3T3-E1 cells. When MC3T3-E1 osteoblastic cells had reached 70-80% confluence, cultures were transferred to a differentiating medium supplemented with 5 mM 2-DG or 10 μM QCT and then irradiated with 2, 4, 6, and 8 Gy. At various times after irradiation, the cells were analyzed for the expression of bone mineralization genes such as ON and OP. The mRNA expression of both ON and OP was increased according to the culture time in the differentiation medium, and the increase of the genes peaked at 14 days after the differentiation induction. In the case of OP, the increase of mRNA expression was maintained to 28 days after the differentiation, while the mRNA level of ON was reduced to the basal level at the same time. Irradiation adding 2-DG showed a significant peak value in the expression pattern of ON at 4 Gy 7 days after irradiation. Irradiation adding QCT increased the mRNA expression of ON and OP in a dose-dependant manner, but irradiation adding 2-DG did not show any differences between the control and experiments 14 days after irradiation. Irradiation adding QCT increased significantly the expression patterns of ON 21 days after irradiation. The results showed that QCT acted as a radiosensitizer in the gene expression of ON and OP during differentiation of the late stage of irradiated MC3T3-E1 osteoblastic cells in vitro.

Ghrelin protects against depleted uranium-induced apoptosis of MC3T3-E1 cells through oxidative stress-mediated p38-mitogen-activated protein kinase pathway

Energy Technology Data Exchange (ETDEWEB)

Hao, Yuhui; Liu, Cong; Huang, Jiawei; Gu, Ying; Li, Hong; Yang, Zhangyou; Liu, Jing [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China); Wang, Weidong, E-mail: wwdwyl@sina.com [Department of Radiation Oncology, Shanghai Jiao Tong University Affiliated Sixth People Hospital, Shanghai 200233 (China); Li, Rong, E-mail: yuhui_hao@126.com [State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, No. 30 Gaotanyan Street, Shapingba District, Chongqing 400038 (China)

2016-01-01

Depleted uranium (DU) mainly accumulates in the bone over the long term. Osteoblast cells are responsible for the formation of bone, and they are sensitive to DU damage. However, studies investigating methods of reducing DU damage in osteoblasts are rarely reported. Ghrelin is a stomach hormone that stimulates growth hormones released from the hypothalamic–pituitary axis, and it is believed to play an important physiological role in bone metabolism. This study evaluates the impact of ghrelin on DU-induced apoptosis of the osteoblast MC3T3-E1 and investigates its underlying mechanisms. The results show that ghrelin relieved the intracellular oxidative stress induced by DU, eliminated reactive oxygen species (ROS) and reduced lipid peroxidation by increasing intracellular GSH levels; in addition, ghrelin effectively suppressed apoptosis, enhanced mitochondrial membrane potential, and inhibited cytochrome c release and caspase-3 activation after DU exposure. Moreover, ghrelin significantly reduced the expression of DU-induced phosphorylated p38-mitogen-activated protein kinase (MAPK). A specific inhibitor (SB203580) or specific siRNA of p38-MAPK could significantly suppress DU-induced apoptosis and related signals, whereas ROS production was not affected. In addition, ghrelin receptor inhibition could reduce the anti-apoptosis effect of ghrelin on DU and reverse the effect of ghrelin on intracellular ROS and p38-MAPK after DU exposure. These results suggest that ghrelin can suppress DU-induced apoptosis of MC3T3-E1 cells, reduce DU-induced oxidative stress by interacting with its receptor, and inhibit downstream p38-MAPK activation, thereby suppressing the mitochondrial-dependent apoptosis pathway. - Highlights: • Ghrelin suppressed DU-induced apoptosis of MC3T3-E1 cells. • Ghrelin inhibited DU-induced oxidative stress and further p38-MAPK activation. • Ghrelin further suppressed mitochondrial-dependent apoptosis pathway. • The anti-oxidation effect of

Behaviors of MC3T3-E1 cells on carbonated apatite films, with a characteristic network structure, fabricated on a titanium plate by aqueous spray coating

International Nuclear Information System (INIS)

Mochizuki, Chihiro; Hara, Hiroki; Oya, Kei; Aoki, Shun; Hayakawa, Tohru; Fujie, Hiromichi; Sato, Mitsunobu

2014-01-01

Four carbonated apatite films having average thicknesses of 1.3–0.11 μm, proportions of network sizes above 10 μm of 41–68%, and average border heights of the characteristic network structure of 0.98–0.29 μm were fabricated on a titanium plate by aqueous spray coating. These carbonated apatite films after heat treatment showed good mineralization ability in Hanks' balanced salt solution. Assessment of initial cell attachment and calcination on these films and on the Ti plate using osteoblastic MC3T3-E1 indicated that the carbonated apatite film heat treated at 600 °C, whose film thickness, proportion of network sizes above 10 μm, and border height were 0.11 μm, 61%, and 0.31 μm, respectively, was most preferred by osteoblastic cells. Field emission scanning electron microscopic observation of the cells attached to the films showed that the wide network and low border height of the network structure on the carbonated apatite film play an important role in the development of the filopodia of the osteoblastic cells. - Highlights: • Osteoblastic MC3T3-E1 behaviors on aqueous spray coating-derived carbonated apatite (CA) films • The network size of CA films is important. • CA films having a low network border height are better for cell proliferation

Behaviors of MC3T3-E1 cells on carbonated apatite films, with a characteristic network structure, fabricated on a titanium plate by aqueous spray coating

Energy Technology Data Exchange (ETDEWEB)

Mochizuki, Chihiro; Hara, Hiroki [Division of Liberal Arts, Kogakuin University, 2665-1 Nakano, Hachioji, Tokyo 192-0015 (Japan); Oya, Kei [Research Institute for Science and Technology, Kogakuin University, 2665-1 Nakano, Hachioji, Tokyo 192-0015 (Japan); School of Engineering, Tokai University, 4-1-1 Kitakanane, Hiratsuka, Kanagawa 259-1292 (Japan); Aoki, Shun [Faculty of System Design, Tokyo Metropolitan University, 6-6 Asahigaoka, Hino, Tokyo 191-0065 (Japan); Hayakawa, Tohru [Department of Dental Engineering, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Yokohama City, Kanagawa 230-8501 (Japan); Fujie, Hiromichi [Faculty of System Design, Tokyo Metropolitan University, 6-6 Asahigaoka, Hino, Tokyo 191-0065 (Japan); Sato, Mitsunobu, E-mail: lccsato@cc.kogakuin.ac.jp [Division of Liberal Arts, Kogakuin University, 2665-1 Nakano, Hachioji, Tokyo 192-0015 (Japan)

2014-06-01

Four carbonated apatite films having average thicknesses of 1.3–0.11 μm, proportions of network sizes above 10 μm of 41–68%, and average border heights of the characteristic network structure of 0.98–0.29 μm were fabricated on a titanium plate by aqueous spray coating. These carbonated apatite films after heat treatment showed good mineralization ability in Hanks' balanced salt solution. Assessment of initial cell attachment and calcination on these films and on the Ti plate using osteoblastic MC3T3-E1 indicated that the carbonated apatite film heat treated at 600 °C, whose film thickness, proportion of network sizes above 10 μm, and border height were 0.11 μm, 61%, and 0.31 μm, respectively, was most preferred by osteoblastic cells. Field emission scanning electron microscopic observation of the cells attached to the films showed that the wide network and low border height of the network structure on the carbonated apatite film play an important role in the development of the filopodia of the osteoblastic cells. - Highlights: • Osteoblastic MC3T3-E1 behaviors on aqueous spray coating-derived carbonated apatite (CA) films • The network size of CA films is important. • CA films having a low network border height are better for cell proliferation.

Expression of cell adhesion and differentiation related genes in MC3T3 osteoblasts plated on titanium alloys: role of surface properties

International Nuclear Information System (INIS)

Sista, Subhash; Wen, Cuie; Hodgson, Peter D.; Pande, Gopal

2013-01-01

It is important to understand the cellular and molecular events that take place at the cell–material interface of implants used for bone repair. An understanding of the mechanisms involved in the initial stages of osteoblast interactions with the surface of the implant material is fundamental in deciding the fate of the cells that come in contact with it. In this study, we compared the relative gene expression of markers that are known to be associated with cell adhesion and differentiation in MC3T3 osteoblast cells, at various time points after plating the cells on surfaces of titanium (Ti) and its two alloys, titanium–zirconium (TiZr) and titanium–niobium (TiNb) by using Quantitative Real Time Polymerase Chain Reaction (RT-PCR). Our analysis indicated that expression of adhesion supporting genes was higher on TiZr surface as compared to Ti and TiNb. The behavior of these genes is possibly driven by a higher surface energy of TiZr. However no significant difference in the expression of differentiation related genes could be seen between the two alloys, although on both substrates it was higher as compared to unalloyed Ti. We propose that substrate composition of the alloys can influence the adhesion and differentiation related gene expression and that Ti alloys are better substrates for inducing osteogenesis as compared to unalloyed Ti. - Highlights: ► Methodology for comparing gene expression in osteoblasts plated on Ti, TiZr or TiNb ► Alloys with higher surface energy (TiZr) induce cell adhesion genes more efficiently ► Alloyed Ti is superior to unalloyed Ti to induce osteoblast differentiation genes

PRELP (proline/arginine-rich end leucine-rich repeat protein) promotes osteoblastic differentiation of preosteoblastic MC3T3-E1 cells by regulating the β-catenin pathway

Energy Technology Data Exchange (ETDEWEB)

Li, Haiying; Cui, Yazhou; Luan, Jing [School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Science, Ji' nan, Shandong (China); Key Laboratory for Rare Disease Research of Shandong Province, Key Laboratory for Biotech Drugs of the Ministry of Health, Shandong Medical Biotechnological Center, Shandong Academy of Medical Sciences, Ji' nan, Shandong (China); Zhang, Xiumei [School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Science, Ji' nan, Shandong (China); Li, Chengzhi; Zhou, Xiaoyan; Shi, Liang [School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Science, Ji' nan, Shandong (China); Key Laboratory for Rare Disease Research of Shandong Province, Key Laboratory for Biotech Drugs of the Ministry of Health, Shandong Medical Biotechnological Center, Shandong Academy of Medical Sciences, Ji' nan, Shandong (China); Wang, Huaxin [Shandong University of Traditional Chinese Medicine, Ji' an, Shandong (China); Han, Jinxiang, E-mail: jxhan9888@aliyun.com [School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Science, Ji' nan, Shandong (China); Key Laboratory for Rare Disease Research of Shandong Province, Key Laboratory for Biotech Drugs of the Ministry of Health, Shandong Medical Biotechnological Center, Shandong Academy of Medical Sciences, Ji' nan, Shandong (China)

2016-02-12

Proline/arginine-rich end leucine-rich repeat protein (PRELP) is a collagen-binding proteoglycan highly expressed in the developing bones. Recent studies indicated that PRELP could inhibit osteoclastogenesis as a NF-κB inhibitor. However, its role during osteoblast differentiation is still unclear. In this study, we confirmed that the expression of PRELP increased with the osteogenesis induction of preosteoblastic MC3T3-E1 cells. Down-regulation of PRELP expression by shRNA reduced ALP activity, mineralization and expression of osteogenic marker gene Runx2. Our microarray analysis data suggested that β-catenin may act as a hub gene in the PRELP-mediated gene network. We validated furtherly that PRELP knockdown could inhibit the level of connexin43, a key regulator of osteoblast differentiation by affecting β-catenin protein expression, and its nuclear translocation in MC3T3-E1 preosteoblasts. Therefore, this study established a new role of PRELP in modulating β-catenin/connexin43 pathway and osteoblast differentiation.

Delivery of the autofluorescent protein R-phycoerythrin by calcium phosphate nanoparticles into four different eukaryotic cell lines (HeLa, HEK293T, MG-63, MC3T3: Highly efficient, but leading to endolysosomal proteolysis in HeLa and MC3T3 cells.

Directory of Open Access Journals (Sweden)

Mathis Kopp

Full Text Available Nanoparticles can be used as carriers to transport biomolecules like proteins and synthetic molecules across the cell membrane because many molecules are not able to cross the cell membrane on their own. The uptake of nanoparticles together with their cargo typically occurs via endocytosis, raising concerns about the possible degradation of the cargo in the endolysosomal system. As the tracking of a dye-labelled protein during cellular uptake and processing is not indicative of the presence of the protein itself but only for the fluorescent label, a label-free tracking was performed with the red-fluorescing model protein R-phycoerythrin (R-PE. Four different eukaryotic cell lines were investigated: HeLa, HEK293T, MG-63, and MC3T3. Alone, the protein was not taken up by any cell line; only with the help of calcium phosphate nanoparticles, an efficient uptake occurred. After the uptake into HeLa cells, the protein was found in early endosomes (shown by the marker EEA1 and lysosomes (shown by the marker Lamp1. There, it was still intact and functional (i.e. properly folded as its red fluorescence was detected. However, a few hours after the uptake, proteolysis started as indicated by the decreasing red fluorescence intensity in the case of HeLa and MC3T3 cells. 12 h after the uptake, the protein was almost completely degraded in HeLa cells and MC3T3 cells. In HEK293T cells and MG-63 cells, no degradation of the protein was observed. In the presence of Bafilomycin A1, an inhibitor of acidification and protein degradation in lysosomes, the fluorescence of R-PE remained intact over the whole observation period in the four cell lines. These results indicate that despite an efficient nanoparticle-mediated uptake of proteins by cells, a rapid endolysosomal degradation may prevent the desired (e.g. therapeutic effect of a protein inside a cell.

Delivery of the autofluorescent protein R-phycoerythrin by calcium phosphate nanoparticles into four different eukaryotic cell lines (HeLa, HEK293T, MG-63, MC3T3): Highly efficient, but leading to endolysosomal proteolysis in HeLa and MC3T3 cells.

Science.gov (United States)

Kopp, Mathis; Rotan, Olga; Papadopoulos, Chrisovalantis; Schulze, Nina; Meyer, Hemmo; Epple, Matthias

2017-01-01

Nanoparticles can be used as carriers to transport biomolecules like proteins and synthetic molecules across the cell membrane because many molecules are not able to cross the cell membrane on their own. The uptake of nanoparticles together with their cargo typically occurs via endocytosis, raising concerns about the possible degradation of the cargo in the endolysosomal system. As the tracking of a dye-labelled protein during cellular uptake and processing is not indicative of the presence of the protein itself but only for the fluorescent label, a label-free tracking was performed with the red-fluorescing model protein R-phycoerythrin (R-PE). Four different eukaryotic cell lines were investigated: HeLa, HEK293T, MG-63, and MC3T3. Alone, the protein was not taken up by any cell line; only with the help of calcium phosphate nanoparticles, an efficient uptake occurred. After the uptake into HeLa cells, the protein was found in early endosomes (shown by the marker EEA1) and lysosomes (shown by the marker Lamp1). There, it was still intact and functional (i.e. properly folded) as its red fluorescence was detected. However, a few hours after the uptake, proteolysis started as indicated by the decreasing red fluorescence intensity in the case of HeLa and MC3T3 cells. 12 h after the uptake, the protein was almost completely degraded in HeLa cells and MC3T3 cells. In HEK293T cells and MG-63 cells, no degradation of the protein was observed. In the presence of Bafilomycin A1, an inhibitor of acidification and protein degradation in lysosomes, the fluorescence of R-PE remained intact over the whole observation period in the four cell lines. These results indicate that despite an efficient nanoparticle-mediated uptake of proteins by cells, a rapid endolysosomal degradation may prevent the desired (e.g. therapeutic) effect of a protein inside a cell.

From 2D to 3D: The morphology, proliferation and differentiation of MC3T3-E1 on silk fibroin/chitosan matrices.

Science.gov (United States)

Li, Da-Wei; He, Feng-Li; He, Jin; Deng, Xudong; Liu, Ya-Li; Liu, Yang-Yang; Ye, Ya-Jing; Yin, Da-Chuan

2017-12-15

It has been widely accepted that cell culture in two-dimensional (2D) conditions may not be able to represent growth in three-dimensional (3D) conditions. Systematic comparisons between 2D and 3D cell cultures are needed to appropriately use the existing 2D results. In this work, we conducted a comparative study between 2D and 3D cell cultures of MC3T3-E1 using the same type of material (a mixture of silk fibroin (SF) and chitosan (CS)). Our results showed 3D SF/CS scaffold exhibited different effects on cell culture compared with the 2D cases. 1) The cells grown in 3D scaffold showed multiple morphologies. 2) The proliferation of cells in 3D scaffold was long-term and sustainable. 3) Cell differentiation occurred throughout the entire 3D scaffold. The results showed that cell culture in 3D SF/CS scaffold exhibited different features than 2D cases and 3D SF/CS scaffold could be a promising material for 3D cell culture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of hierarchical pore structure on ALP expression of MC3T3-E1 cells on bioglass films.

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Yu, Cuixia; Zhuang, Junjun; Dong, Lingqing; Cheng, Kui; Weng, Wenjian

2017-08-01

Hierarchical porous bioglass films on the tantalum were designed to enhance osteointegration of metallic implants. The films were prepared by a sol-gel method using P123 as the mesopore template and polystyrene microsphere as the nanopore template. The films with 5.4nm mesopores and 100nm nanopores (MBG-100) elicited an obviously elongated morphology of the cultured MC3T3-E1 cells, as a result, a higher alkaline phosphatase level was expressed. It is suggested that the nanopores play an important role in regulating cellular behavior by initial protein adsorption through nanopore curvatures. The mesopores were proven very effective for loading rhBMP-2, and the rhBMP-2 loaded on MBG-100 films showed a better function of enhancing osteogenic differentiation, which is attributed to that the nanopore structure could expedite rhBMP-2 release and provide a microenvironment for intensifying the interaction of rhBMP-2 with the cells. Hence, the cell osteogenic differentiation can be enhanced by hierarchical porous bioglass films through both the porous structure and rhBMP-2 induction. Copyright © 2017 Elsevier B.V. All rights reserved.

High levels of the type III inorganic phosphate transporter PiT1 (SLC20A1) can confer faster cell adhesion

DEFF Research Database (Denmark)

Kongsfelt, Iben Boutrup; Byskov, Kristina; Pedersen, Lasse Ebdrup

2014-01-01

overexpression led to faster cell spreading. The final total numbers of attached cells did, however, not differ between cultures of PiT1 overexpressing cells and control cells of neither cell type. We suggest that the PiT1-mediated fast adhesion potentials allow the cells to go faster out of G0/G1 and thereby......The inorganic phosphate transporter PiT1 (SLC20A1) is ubiquitously expressed in mammalian cells. We recently showed that overexpression of human PiT1 was sufficient to increase proliferation of two strict density-inhibited cell lines, murine fibroblastic NIH3T3 and pre-osteoblastic MC3T3-E1 cells......, and allowed the cultures to grow to higher cell densities. In addition, upon transformation NIH3T3 cells showed increased ability to form colonies in soft agar. The cellular regulation of PiT1 expression supports that cells utilize the PiT1 levels to control proliferation, with non-proliferating cells showing...

Magnetically actuated mechanical stimuli on Fe3O4/mineralized collagen coatings to enhance osteogenic differentiation of the MC3T3-E1 cells.

Science.gov (United States)

Zhuang, Junjun; Lin, Suya; Dong, Lingqing; Cheng, Kui; Weng, Wenjian

2018-04-15

Mechanical stimuli at the bone-implant interface are considered to activate the mechanotransduction pathway of the cell to improve the initial osseointegration establishment and to guarantee clinical success of the implant. However, control of the mechanical stimuli at the bone-implant interface still remains a challenge. In this study, we have designed a strategy of a magnetically responsive coating on which the mechanical stimuli is controlled because of coating deformation under static magnetic field (SMF). The iron oxide nanoparticle/mineralized collagen (IOP-MC) coatings were electrochemically codeposited on titanium substrates in different quantities of IOPs and distributions; the resulting coatings were verified to possess swelling behavior with flexibility same as that of hydrogel. The relative quantity of IOP to collagen and the IOP distribution in the coatings were demonstrated to play a critical role in mediating cell behavior. The cells present on the outer layer of the distributed IOP-MC (O-IOP-MC) coating with a mass ratio of 0.67 revealed the most distinct osteogenic differentiation activity being promoted, which could be attributed to the maximized mechanical stimuli with exposure to SMF. Furthermore, the enhanced osteogenic differentiation of the stimulated MC3T3-E1 cells originated from magnetically actuated mechanotransduction signaling pathway, embodying the upregulated expression of osteogenic-related and mechanotransduction-related genes. This work therefore provides a promising strategy for implementing mechanical stimuli to activate mechanotransduction on the bone-implant interface and thus to promote osseointegration. The magnetically actuated coating is designed to produce mechanical stimuli to cells for promoting osteogenic differentiation based on the coating deformation. Iron oxide nanoparticles (IOPs) were incorporated into the mineralized collagen coatings (MC) forming the composite coatings (IOP-MC) with spatially distributed IOPs

An axial distribution of seeding, proliferation, and osteogenic differentiation of MC3T3-E1 cells and rat bone marrow-derived mesenchymal stem cells across a 3D Thai silk fibroin/gelatin/hydroxyapatite scaffold in a perfusion bioreactor

Energy Technology Data Exchange (ETDEWEB)

Sinlapabodin, Salita; Amornsudthiwat, Phakdee; Damrongsakkul, Siriporn; Kanokpanont, Sorada, E-mail: sorada.k@chula.ac.th

2016-01-01

In cell culture, a perfusion bioreactor provides effective transportation of nutrients, oxygen, and waste removal to and from the core of the scaffold. In addition, it provides mechanical stimuli for enhancing osteogenic differentiation. In this study, we used an axial distribution of cell numbers, alkaline phosphatase (ALP) enzyme activity, and calcium content across 4 cross-sections of 10 mm thick scaffold, made of Thai silk fibroin (SF)/gelatin (G)/hydroxyapatite (HA), as a tool to evaluate the suitable perfusion flow rate. These evaluations cover all cellular developmental phases starting from seeding, to proliferation, and later osteogenic differentiation. Mouse pre-osteoblastic MC3T3-E1 cell lines were used as a cell model during seeding and proliferation. The bioreactor seeded scaffold provided more uniform cell distribution across the scaffold compared to centrifugal and agitation seeding, while the overall number of adhered cells from bioreactor seeding was slightly lower than agitation seeding. The dynamic culture using 1 ml/min perfusion flow rate (initial shear stress of 0.1 dyn/cm{sup 2}) enabled statistically higher MC3T3-E1 proliferation, ALP activity, and calcium deposition than those observed in the static-culturing condition. However, the perfusion flow rate of 1 ml/min seemed not to be enough for enhancing ALP expression across all sections of the scaffold. Rat bone marrow derived stromal cells (rMSC) were used in the detachment test and osteogenic differentiation. It was found that perfusion flow rate of 5 ml/min caused statistically higher cell detachment than that of 1 and 3 ml/min. The perfusion flow rate of 3 ml/min gave the highest rMSC osteogenic differentiation on a SF/G/HA scaffold than other flow rates, as observed from the significantly highest number of ALP enzyme activity and the calcium content without any significant cell growth. In addition, all of these parameters were evenly distributed across all scaffold sections. - Highlights

Knockdown of Indian hedgehog protein induces an inhibition of cell growth and differentiation in osteoblast MC3T3-E1 cells

Science.gov (United States)

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

2017-01-01

Indian hedgehog protein (Ihh) is evolutionarily conserved and serves important roles in controlling the differentiation of progenitor cells into osteoblasts. Ihh null mutant mice exhibit a failure of osteoblast development in endochondral bone. Although studies have demonstrated that Ihh signaling is a potent local factor that regulates osteoblast differentiation, the specific transcription factors that determine osteoblast differentiation remain unclear. Further studies are required to determine the precise mechanism through which Ihh regulates osteoblast differentiation. In the present study, Ihh was knocked down in osteoblast MC3T3-E1 cells using short hairpin RNA, to investigate the function of Ihh in osteoblast proliferation and differentiation and to examine the potential mechanism through which Ihh induces osteoblast apoptosis and cell cycle arrest. It was observed that the knockdown of Ihh induced a marked inhibition of cell growth and increased the apoptosis rate compared with the negative control osteoblasts. Downregulation of Ihh resulted in a cell cycle arrest at the G1 to S phase boundary in osteoblasts. In addition, the knockdown of Ihh decreased the alkaline phosphatase activity and mineral deposition of osteoblasts. The inhibitory roles of Ihh downregulation in osteoblast growth and differentiation may be associated with the transforming growth factor-β/mothers against decapentaplegic homolog and tumor necrosis factor receptor superfamily member 11B/tumor necrosis factor ligand superfamily member 11 signaling pathways. Manipulating either Ihh expression or its signaling components may be of benefit for the treatment of skeletal diseases. PMID:28990069

Effects of Apatite Cement Containing Atelocollagen on Attachment to and Proliferation and Differentiation of MC3T3-E1 Osteoblastic Cells

Directory of Open Access Journals (Sweden)

Masaaki Takechi

2016-04-01

Full Text Available To improve the osteoconductivity of apatite cement (AC for reconstruction of bone defects after oral maxillofacial surgery, we previously fabricated AC containing atelocollagen (AC(ate. In the present study, we examined the initial attachment, proliferation and differentiation of mouse osteoblastic cells (MC3T3-E1 cells on the surface of conventional AC (c-AC, AC(ate and a plastic cell dish. The number of osteoblastic cells showing initial attachment to AC(ate was greater than those attached to c-AC and similar to the number attached to the plastic cell wells. We also found that osteoblastic cells were well spread and increased their number on AC(ate in comparison with c-AC and the wells without specimens, while the amount of procollagen type I carboxy-terminal peptide (PIPC produced in osteoblastic cells after three days on AC(ate was greater as compared to the others. There was no significant difference in regard to alkaline phosphatase (ALP activity and osteocalcin production by osteoblastic cells among the three surface types after three and six days. However, after 12 days, ALP activity and the produced osteocalcin were greater with AC(ate. In conclusion, AC(ate may be a useful material with high osteoconductivity for reconstruction of bone defects after oral maxillofacial surgery.

Knockdown of Indian hedgehog protein induces an inhibition of cell growth and differentiation in osteoblast MC3T3‑E1 cells.

Science.gov (United States)

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

2017-12-01

Indian hedgehog protein (Ihh) is evolutionarily conserved and serves important roles in controlling the differentiation of progenitor cells into osteoblasts. Ihh null mutant mice exhibit a failure of osteoblast development in endochondral bone. Although studies have demonstrated that Ihh signaling is a potent local factor that regulates osteoblast differentiation, the specific transcription factors that determine osteoblast differentiation remain unclear. Further studies are required to determine the precise mechanism through which Ihh regulates osteoblast differentiation. In the present study, Ihh was knocked down in osteoblast MC3T3‑E1 cells using short hairpin RNA, to investigate the function of Ihh in osteoblast proliferation and differentiation and to examine the potential mechanism through which Ihh induces osteoblast apoptosis and cell cycle arrest. It was observed that the knockdown of Ihh induced a marked inhibition of cell growth and increased the apoptosis rate compared with the negative control osteoblasts. Downregulation of Ihh resulted in a cell cycle arrest at the G1 to S phase boundary in osteoblasts. In addition, the knockdown of Ihh decreased the alkaline phosphatase activity and mineral deposition of osteoblasts. The inhibitory roles of Ihh downregulation in osteoblast growth and differentiation may be associated with the transforming growth factor‑β/mothers against decapentaplegic homolog and tumor necrosis factor receptor superfamily member 11B/tumor necrosis factor ligand superfamily member 11 signaling pathways. Manipulating either Ihh expression or its signaling components may be of benefit for the treatment of skeletal diseases.

A genomic characterization of the influence of silver nanoparticles on bone differentiation in MC3T3-E1 cells.

Science.gov (United States)

Qing, Tao; Mahmood, Meena; Zheng, Yuanting; Biris, Alexandru S; Shi, Leming; Casciano, Daniel A

2018-02-01

Silver nanoparticles (AgNPs) have been widely used in a variety of biomedical applications. Previous studies demonstrated that AgNPs significantly enhanced bone cell mineralization and differentiation in MC3T3-1 cells, a model in vitro system, when compared to several other NPs. This increased bone deposition was evaluated by phenotypic measurements and assessment of the expression of miRNAs associated with regulation of bone morphogenic proteins. In the present study, we used RNA-seq technology, a more direct measurement of gene expression, to investigate further the mechanisms of bone differentiation induced by AgNP treatment. Key factors associated with the osteoclast pathway were significantly increased in response to AgNP exposure including Bmp4, Bmp6 and Fosl1. In addition, genes of metabolism and toxicity pathways were significantly regulated as well. Although this study suggests the potential for AgNPs to influence bone morphogenesis in injury or disease applications, further investigation into the efficacy and safety of AgNPs in bone regeneration is warranted. Copyright © 2017 John Wiley & Sons, Ltd.

Tunable swelling of polyelectrolyte multilayers in cell culture media for modulating NIH-3T3 cells adhesion.

Science.gov (United States)

Qi, Wei; Cai, Peng; Yuan, Wenjing; Wang, Hua

2014-11-01

For polyelectrolyte multilayers (PEMs) assembled by the layer-by-layer (LbL) assembly technique, their nanostructure and properties can be governed by many parameters during the building process. Here, it was demonstrated that the swelling of the PEMs containing poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrenesulfonate) (PSS) in cell culture media could be tuned with changing supporting salt solutions during the assembly process. Importantly, the influence of the PEMs assembled in different salt solutions on NIH-3T3 cell adhesion was observable. Specifically, the cells could possess a higher affinity for the films assembled in low salt concentration (i.e. 0.15M NaCl) or no salt, the poorly swelling films in cell culture media, which was manifested by the large cell spreading area and focal adhesions. In contrast, those were assembled in higher salt concentration, highly swelling films in cell culture media, were less attractive for the fibroblasts. As a result, the cell adhesion behaviors may be manipulated by tailoring the physicochemical properties of the films, which could be performed by changing the assembly conditions such as supporting salt concentration. Such a finding might promise a great potential in designing desired biomaterials for tissue engineering and regenerative medicine. © 2014 Wiley Periodicals, Inc.

The in vitro effects of macrophages on the osteogenic capabilities of MC3T3-E1 cells encapsulated in a biomimetic poly(ethylene glycol) hydrogel.

Science.gov (United States)

Saleh, Leila S; Carles-Carner, Maria; Bryant, Stephanie J

2018-04-15

Poly(ethylene glycol) PEG-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in vivo. The goal of this study was to investigate the impact of the FBR, and specifically the presence of inflammatory macrophages, on encapsulated cells and their ability to synthesize new extracellular matrix. This study employed an in vitro co-culture system with murine macrophages and MC3T3-E1 pre-osteoblasts encapsulated in a bone-mimetic hydrogel, which were cultured in transwell inserts, and exposed to an inflammatory stimulant, lipopolysaccharide (LPS). The co-culture was compared to mono-cultures of the cell-laden hydrogels alone and with LPS over 28 days. Two macrophage cell sources, RAW 264.7 and primary derived, were investigated. The presence of LPS-stimulated primary macrophages led to significant changes in the cell-laden hydrogel by a 5.3-fold increase in percent apoptotic osteoblasts at day 28, 4.2-fold decrease in alkaline phosphatase activity at day 10, and 7-fold decrease in collagen deposition. The presence of LPS-stimulated RAW macrophages led to significant changes in the cell-laden hydrogel by 5-fold decrease in alkaline phosphatase activity at day 10 and 4-fold decrease in collagen deposition. Mineralization, as measured by von Kossa stain or quantified by calcium content, was not sensitive to macrophages or LPS. Elevated interleukin-6 and tumor necrosis factor-α secretion were detected in mono-cultures with LPS and co-cultures. Overall, primary macrophages had a more severe inhibitory effect on osteoblast differentiation than the macrophage cell line, with greater apoptosis and collagen I reduction. In summary, this study highlights the detrimental effects of macrophages on encapsulated cells for bone tissue engineering. Poly(ethylene glycol) (PEG)-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in

Direct effects of casein phosphopeptides on growth and differentiation of in vitro cultured osteoblastic cells (MC3T3-E1).

Science.gov (United States)

Tulipano, Giovanni; Bulgari, Omar; Chessa, Stefania; Nardone, Alessandro; Cocchi, Daniela; Caroli, Anna

2010-02-25

Casein phosphopeptides (CPPs) obtained by enzymatic hydrolysis in vitro of caseins, have been shown to enhance calcium solubility and to increase the calcification of embryonic rat bones in their diaphyseal area. Little is known about the direct effects of CPPs on cultured osteoblastic cells. Calcium in the microenvironment surrounding bone cells is not only important for the mineralization of the extracellular matrix, but it is believed to provide preosteblasts with a signal that modulates their proliferation and differentiation. The aim of the present study was to investigate the direct effects of four selected casein phosphopeptides on osteoblastic cell (MC3T3-E1 cells) viability and differentiation. The selected peptides have been obtained by chemical synthesis and differed in the number of phosphorylated sites and in the amino acid spacing out two phosphorylated sites, in order to further characterize the relationship between structure and function. The results obtained in this work demonstrated that CPPs may directly affect osteoblast-like cell growth, calcium uptake and ultimately calcium deposition in the extracellular matrix. The effects exerted by distinct CPPs on osteogenesis in vitro can be either stimulatory or inhibitory. Differential short amino acid sequences in their molecules, like the -SpEE- and the -SpTSpEE-motifs, are likely the molecular determinants for their biological activities on osteoblastic cells. Moreover, two genetic variants of CPPs showing one amino acid change in their sequence may profoundly differ in their biological activities. Finally, our data may also suggest important clues about the role of intrinsic phosphorylated peptides derived from endogenous phosphorylated proteins in bone metabolism, apart from extrinsic CPPs. Copyright 2009 Elsevier B.V. All rights reserved.

The corrosion and biological behaviour of titanium alloys in the presence of human lymphoid cells and MC3T3-E1 osteoblasts

International Nuclear Information System (INIS)

Zhang Yumei; Zhao Yimin; Chai Feng; Hildebrand, Hartmut F; Hornez, Jean-Christophe; Li, Chang Liang; Traisnel, Michel

2009-01-01

Corrosion behaviour of biomedical alloys is generally determined in mineral electrolytes: unbuffered NaCl 0.9% (pH 7.4) or artificial saliva (pH 6.8). The assays with exclusive utilization of these electrolytes are of low relevance for the biological condition, to which the alloys will be exposed once implanted in the human organism. As an approach to the biological situation regarding the interaction of proteins, electrolytes and metals, we added the RPMI cell culture medium containing foetal calf serum as a biological electrolyte (pH 7.0). The analysis of corrosion behaviour was also performed in the presence of human lymphoid cells (CEM). The rest potential (E r ) and the global polarization were determined on cp-Ti, micro-arc oxidized cp-Ti (MAO-Ti), four different Ti-alloys (Ti6Al4V, Ti12Zr, Ti(AlMoZr), Ti(NbTaZr)) and 316L stainless steel. The 316L exhibited an appropriate E r and a good passive current density (I p ), but a high corrosion potential (E c ) and a very low breakdown potential (E b ) in all electrolytes. All Ti-alloys exhibited a much better electrochemical behaviour: better E r and E c and very high E b . No significant differences of the above parameters existed between the Ti-alloys, except for Zr-containing alloys that showed better corrosion behaviour. A remarkable difference, however, was stated with respect to the electrolytes. NaCl 0.9% induced strong variations between the Ti-alloys. More homogeneous results were obtained with artificial saliva and RPMI medium, which induced a favourable E c and an increased I p . The presence of cells further decreased these values. The unbuffered NaCl solution seems to be less appropriate for the analysis of corrosion of metals. Additional in vitro biological assessments with CEM cell suspensions and MC3T3-E1 osteoblasts confirmed the advantages of the Ti(AlMoZr) and Ti(NbTaZr) alloys with an improved cell proliferation and vitality rate.

Icaritin induces MC3T3-E1 subclone14 cell differentiation through estrogen receptor-mediated ERK1/2 and p38 signaling activation.

Science.gov (United States)

Wu, Zhidi; Ou, Ling; Wang, Chaopeng; Yang, Li; Wang, Panpan; Liu, Hengrui; Xiong, Yingquan; Sun, Kehuan; Zhang, Ronghua; Zhu, Xiaofeng

2017-10-01

Icaritin (ICT), a hydrolytic product of icariin from the genus Epimedium, has many indicated pharmacological and biological activities. Several studies have shown that ICT has potential osteoprotective effects, including stimulation of osteoblast differentiation and inhibition of osteoclast differentiation. However, the molecular mechanism for this anabolic action of ICT remains largely unknown. Here, we found that ICT could enhance MC3T3-E1 subclone 14 preosteoblastic cell differentiation associated with increased mRNA levels and protein expression of the differentiation markers alkaline phosphatase (ALP), type 1 collagen (COL1), osteocalcin (OC), osteoponin (OPN) and runt-related transcription factor 2 (RUNX2), and improved mineralization, confirmed by bone nodule formation and collagen synthesis. To characterize the underlying mechanisms, we examined the effect of ICT on estrogen receptor (ER) and mitogen-activated protein kinase (MAPK) signaling. ICT treatment induced p38 kinase and extracellular signal-regulated kinase 1/2 (ERK1/2) activation, but it demonstrated at the same time point no effect on activation of c-Jun N-terminal kinase (JNK). ER antagonist ICI182780, p38 antagonist SB203580 and ERK1/2 antagonist PD98059 markedly inhibited the ICT-induced the mRNA expression of ALP, COL1, OC and OPN. ICI182780 attenuated the ICT-induced phosphorylation of p38 and ERK1/2. These observations indicate a potential mechanism of osteogenic effects of ICT involving the ERK1/2 and p38 pathway activation through the ER. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

MHC class II ligation induces CD58 (LFA-3)-mediated adhesion in human T cells

DEFF Research Database (Denmark)

Nielsen, M; Gerwien, J; Geisler, C

1998-01-01

ligation induces homotypic adhesion in both beta2-integrin-positive and negative, CD4-positive T cell lines. Anti-CD18 monoclonal antibody (mAb) weakly inhibited the adhesion response in beta2-integrin-positive T cells and had no effect on beta2-integrin-negative T cells. In contrast, an anti-CD58 (LFA-3...

High levels of the type III inorganic phosphate transporter PiT1 (SLC20A1) can confer faster cell adhesion

OpenAIRE

Kongsfelt, Iben Boutrup; Byskov, Kristina; Pedersen, Lasse Ebdrup; Pedersen, Lene

2014-01-01

The inorganic phosphate transporter PiT1 (SLC20A1) is ubiquitously expressed in mammalian cells. We recently showed that overexpression of human PiT1 was sufficient to increase proliferation of two strict density-inhibited cell lines, murine fibroblastic NIH3T3 and pre-osteoblastic MC3T3-E1 cells, and allowed the cultures to grow to higher cell densities. In addition, upon transformation NIH3T3 cells showed increased ability to form colonies in soft agar. The cellular regulation of PiT1 expre...

Traf2 interacts with Smad4 and regulates BMP signaling pathway in MC3T3-E1 osteoblasts

International Nuclear Information System (INIS)

Shimada, Koichi; Ikeda, Kyoko; Ito, Koichi

2009-01-01

Bone morphogenetic proteins (BMPs) play important roles in osteoblast differentiation and maturation. In mammals, the BMP-induced receptor-regulated Smads form complexes with Smad4. These complexes translocate and accumulate in the nucleus, where they regulate the transcription of various target genes. However, the function of Smad4 remains unclear. We performed a yeast two-hybrid screen using Smad4 as bait and a cDNA library derived from bone marrow, to indentify the proteins interacting with Smad4. cDNA clones for Tumor necrosis factor (TNF) receptor-associated factor 2 (Traf2) were identified, and the interaction between the endogenous proteins was confirmed in the mouse osteoblast cell line MC3T3-E1. To investigate the function of Traf2, we silenced it with siRNA. The level of BMP-2 protein in the medium, the expression levels of the Bmp2 gene and BMP-induced transcription factor genes, including Runx2, Dlx5, Msx2, and Sp7, and the phosphorylated-Smad1 protein level were increased in cells transfected with Traf2 siRNA. The nuclear accumulation of Smad1 increased with TNF-α stimulation for 30 min at Traf2 silencing. These results suggest that the TNF-α-stimulated nuclear accumulation of Smad1 may be dependent on Traf2. Thus, the interaction between Traf2 and Smad4 may play a role in the cross-talk between TNF-α and BMP signaling pathways.

In vitro behavior of MC3T3-E1 preosteoblast with different annealing temperature titania nanotubes.

Science.gov (United States)

Yu, W Q; Zhang, Y L; Jiang, X Q; Zhang, F Q

2010-10-01

Titanium oxide nanotube layers by anodization have excellent potential for dental implants because of good bone cell promotion. It is necessary to evaluate osteoblast behavior on different annealing temperature titania nanotubes for actual implant designs.  Scanning Electron Microscopy, X-Ray polycrystalline Diffractometer (XRD), X-ray photoelectron Spectroscope, and Atomic Force Microscopy (AFM) were used to characterize the different annealing temperature titania nanotubes. Confocal laser scanning microscopy, MTT, and Alizarin Red-S staining were used to evaluate the MC3T3-E1 preosteoblast behavior on different annealing temperature nanotubes.  The tubular morphology was constant when annealed at 450°C and 550°C, but collapsed when annealed at 650°C. XRD exhibited the crystal form of nanotubes after formation (amorphous), after annealing at 450°C (anatase), and after annealing at 550°C (anatase/rutile). Annealing led to the complete loss of fluorine on nanotubes at 550°C. Average surface roughness of different annealing temperature nanotubes showed no difference by AFM analysis. The proliferation and mineralization of preostoblasts cultured on anatase or anatase/rutile nanotube layers were shown to be significantly higher than smooth, amorphous nanotube layers.  Annealing can change the crystal form and composition of nanotubes. The nanotubes after annealing can promote osteoblast proliferation and mineralization in vitro. © 2010 John Wiley & Sons A/S.

Micro–adhesion rings surrounding TCR microclusters are essential for T cell activation

Science.gov (United States)

Sakuma, Machie; Yokosuka, Tadashi

2016-01-01

The immunological synapse (IS) formed at the interface between T cells and antigen-presenting cells represents a hallmark of initiation of acquired immunity. T cell activation is initiated at T cell receptor (TCR) microclusters (MCs), in which TCRs and signaling molecules assemble at the interface before IS formation. We found that each TCR-MC was transiently bordered by a ring structure made of integrin and focal adhesion molecules in the early phase of activation, which is similar in structure to the IS in microscale. The micro–adhesion ring is composed of LFA-1, focal adhesion molecules paxillin and Pyk2, and myosin II (MyoII) and is supported by F-actin core and MyoII activity through LFA-1 outside-in signals. The formation of the micro–adhesion ring was transient but especially sustained upon weak TCR stimulation to recruit linker for activation of T cells (LAT) and SLP76. Perturbation of the micro–adhesion ring induced impairment of TCR-MC development and resulted in impaired cellular signaling and cell functions. Thus, the synapse-like structure composed of the core TCR-MC and surrounding micro–adhesion ring is a critical structure for initial T cell activation through integrin outside-in signals. PMID:27354546

Structure, MC3T3-E1 cell response, and osseointegration of macroporous titanium implants covered by a bioactive microarc oxidation coating with microporous structure.

Science.gov (United States)

Zhou, Rui; Wei, Daqing; Cheng, Su; Feng, Wei; Du, Qing; Yang, Haoyue; Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu

2014-04-09

Macroporous Ti with macropores of 50-400 μm size is prepared by sintering Ti microbeads with different diameters of 100, 200, 400, and 600 μm. Bioactive microarc oxidation (MAO) coatings with micropores of 2-5 μm size are prepared on the macroporous Ti. The MAO coatings are composed of a few TiO2 nanocrystals and lots of amorphous phases with Si, Ca, Ti, Na, and O elements. Compared to compact Ti, the MC3T3-E1 cell attachment is prolonged on macroporous Ti without and with MAO coatings; however, the cell proliferation number increases. These results are contributed to the effects of the space structure of macroporous Ti and the surface chemical feature and element dissolution of the MAO coatings during the cell culture. Macroporous Ti both without and with MAO coatings does not cause any adverse effects in vivo. The new bone grows well into the macropores and micropores of macroporous Ti with MAO coatings, showing good mechanical properties in vivo compared to Ti, MAO-treated Ti, and macroporous Ti because of its excellent osseointegration. Moreover, the MAO coatings not only show a high interface bonding strength with new bones but also connect well with macroporous Ti. Furthermore, the pushing out force for macroporous Ti with MAO coatings increases significantly with increasing microbead diameter.

Layer-by-layer assembly of peptide based bioorganic–inorganic hybrid scaffolds and their interactions with osteoblastic MC3T3-E1 cells

International Nuclear Information System (INIS)

Romanelli, Steven M.; Fath, Karl R.; Phekoo, Aruna P.; Knoll, Grant A.; Banerjee, Ipsita A.

2015-01-01

In this work we have developed a new family of biocomposite scaffolds for bone tissue regeneration by utilizing self-assembled fluorenylmethyloxycarbonyl protected Valyl-cetylamide (FVC) nanoassemblies as templates. To tailor the assemblies for enhanced osteoblast attachment and proliferation, we incorporated (a) Type I collagen, (b) a hydroxyapatite binding peptide sequence (EDPHNEVDGDK) derived from dentin sialophosphoprotein and (c) the osteoinductive bone morphogenetic protein-4 (BMP-4) to the templates by layer-by-layer assembly. The assemblies were then incubated with hydroxyapatite nanocrystals blended with varying mass percentages of TiO 2 nanoparticles and coated with alginate to form three dimensional scaffolds for potential applications in bone tissue regeneration. The morphology was examined by TEM and SEM and the binding interactions were probed by FITR spectroscopy. The scaffolds were found to be non-cytotoxic, adhered to mouse preosteoblast MC3T3-E1 cells and promoted osteogenic differentiation as indicated by the results obtained by alkaline phosphatase assay. Furthermore, they were found to be biodegradable and possessed inherent antibacterial capability. Thus, we have developed a new family of tissue-engineered biocomposite scaffolds with potential applications in bone regeneration. - Highlights: • Fmoc-val-cetylamide assemblies were used as templates. • Collagen, a short dentin sialophosphoprotein derived sequence and BMP-4 were incorporated. • Hydroxyapatite–TiO 2 nanocomposite blends and alginate were incorporated. • The 3D scaffold biocomposites adhered to preosteoblasts and promoted osteoblast differentiation. • The biocomposites also displayed antimicrobial activity

Layer-by-layer assembly of peptide based bioorganic–inorganic hybrid scaffolds and their interactions with osteoblastic MC3T3-E1 cells

Energy Technology Data Exchange (ETDEWEB)

Romanelli, Steven M. [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States); Fath, Karl R. [The City University of New York, Queens College, Department of Biology, 65-30 Kissena Blvd, Flushing, NY 11367 (United States); The Graduate Center, The City University of New York, 365 Fifth Avenue, NY 10016 (United States); Phekoo, Aruna P. [The City University of New York, Queens College, Department of Biology, 65-30 Kissena Blvd, Flushing, NY 11367 (United States); Knoll, Grant A. [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States); Banerjee, Ipsita A., E-mail: banerjee@fordham.edu [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States)

2015-06-01

In this work we have developed a new family of biocomposite scaffolds for bone tissue regeneration by utilizing self-assembled fluorenylmethyloxycarbonyl protected Valyl-cetylamide (FVC) nanoassemblies as templates. To tailor the assemblies for enhanced osteoblast attachment and proliferation, we incorporated (a) Type I collagen, (b) a hydroxyapatite binding peptide sequence (EDPHNEVDGDK) derived from dentin sialophosphoprotein and (c) the osteoinductive bone morphogenetic protein-4 (BMP-4) to the templates by layer-by-layer assembly. The assemblies were then incubated with hydroxyapatite nanocrystals blended with varying mass percentages of TiO{sub 2} nanoparticles and coated with alginate to form three dimensional scaffolds for potential applications in bone tissue regeneration. The morphology was examined by TEM and SEM and the binding interactions were probed by FITR spectroscopy. The scaffolds were found to be non-cytotoxic, adhered to mouse preosteoblast MC3T3-E1 cells and promoted osteogenic differentiation as indicated by the results obtained by alkaline phosphatase assay. Furthermore, they were found to be biodegradable and possessed inherent antibacterial capability. Thus, we have developed a new family of tissue-engineered biocomposite scaffolds with potential applications in bone regeneration. - Highlights: • Fmoc-val-cetylamide assemblies were used as templates. • Collagen, a short dentin sialophosphoprotein derived sequence and BMP-4 were incorporated. • Hydroxyapatite–TiO{sub 2} nanocomposite blends and alginate were incorporated. • The 3D scaffold biocomposites adhered to preosteoblasts and promoted osteoblast differentiation. • The biocomposites also displayed antimicrobial activity.

Short-term administration of small molecule phenamil induced a protracted osteogenic effect on osteoblast-like MC3T3-E1 cells.

Science.gov (United States)

Lo, Kevin W-H; Kan, Ho Man; Laurencin, Cato T

2016-06-01

Sustained administration (21-day treatment) of the small molecule phenamil has been proposed as an alternative osteogenic factor when used in conjunction with a biodegradable scaffold for in vitro osteogenesis. While promising, the major issue associated with small molecules is non-specific cytotoxicity. The aim of this study was to minimize the side-effects from small-molecule drugs by reducing the frequency of administration. Toward this goal, we investigated whether a shorter phenamil treatment is sufficient to induce in vitro osteogenesis. We compared the effects of short-term (12 h) and continuous treatments of phenamil on osteoblastic differentiation and mineralization. Alkaline phosphatase (ALP) and osteopontin (OPN) activity were used as markers for osteoblastic differentiation. Measurement of the calcium content of the extracellular matrix was used as the hallmark for in vitro bone formation after 21 days of culture. Our findings revealed that both short and continuous phenamil treatment triggers osteoblastic differentiation and mineralization of MC3T3-E1 cells on a biodegradable polymeric scaffold composed of polylactic-co-glycolic acid (PLAGA) at the same time points. In addition, in order to fabricate a phenamil-loaded PLAGA scaffold, the small molecule phenamil was physically absorbed onto the surface of scaffolds and the bioactivity of the loaded scaffolds was evaluated. Furthermore, biochemical analysis indicated that short phenamil treatment of cells was accompanied by upregulation in protein expression of integrin α5, p125(FAK) and phosphorylation of CREB. These effects may contribute to the downstream signalling cascade necessary for osteogenesis, and such responses may account for our observed protracted osteogenic differentiation in vitro. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A Nanodot Array Modulates Cell Adhesion and Induces an Apoptosis-Like Abnormality in NIH-3T3 Cells

Directory of Open Access Journals (Sweden)

Hung Yao-Ching

2009-01-01

Full Text Available Abstract Micro-structures that mimic the extracellular substratum promote cell growth and differentiation, while the cellular reaction to a nanostructure is poorly defined. To evaluate the cellular response to a nanoscaled surface, NIH 3T3 cells were grown on nanodot arrays with dot diameters ranging from 10 to 200 nm. The nanodot arrays were fabricated by AAO processing on TaN-coated wafers. A thin layer of platinum, 5 nm in thickness, was sputtered onto the structure to improve biocompatibility. The cells grew normally on the 10-nm array and on flat surfaces. However, 50-nm, 100-nm, and 200-nm nanodot arrays induced apoptosis-like events. Abnormality was triggered after as few as 24 h of incubation on a 200-nm dot array. For cells grown on the 50-nm array, the abnormality started after 72 h of incubation. The number of filopodia extended from the cell bodies was lower for the abnormal cells. Immunostaining using antibodies against vinculin and actin filament was performed. Both the number of focal adhesions and the amount of cytoskeleton were decreased in cells grown on the 100-nm and 200-nm arrays. Pre-coatings of fibronectin (FN or type I collagen promoted cellular anchorage and prevented the nanotopography-induced programed cell death. In summary, nanotopography, in the form of nanodot arrays, induced an apoptosis-like abnormality for cultured NIH 3T3 cells. The occurrence of the abnormality was mediated by the formation of focal adhesions.

The corrosion and biological behaviour of titanium alloys in the presence of human lymphoid cells and MC3T3-E1 osteoblasts.

Science.gov (United States)

Zhang, Yu Mei; Chai, Feng; Hornez, Jean-Christophe; Li, Chang Liang; Zhao, Yi Min; Traisnel, Michel; Hildebrand, Hartmut F

2009-02-01

Corrosion behaviour of biomedical alloys is generally determined in mineral electrolytes: unbuffered NaCl 0.9% (pH 7.4) or artificial saliva (pH 6.8). The assays with exclusive utilization of these electrolytes are of low relevance for the biological condition, to which the alloys will be exposed once implanted in the human organism. As an approach to the biological situation regarding the interaction of proteins, electrolytes and metals, we added the RPMI cell culture medium containing foetal calf serum as a biological electrolyte (pH 7.0). The analysis of corrosion behaviour was also performed in the presence of human lymphoid cells (CEM). The rest potential (Er) and the global polarization were determined on cp-Ti, micro-arc oxidized cp-Ti (MAO-Ti), four different Ti-alloys (Ti6Al4V, Ti12Zr, Ti(AlMoZr), Ti(NbTaZr)) and 316L stainless steel. The 316L exhibited an appropriate Er and a good passive current density (Ip), but a high corrosion potential (Ec) and a very low breakdown potential (Eb) in all electrolytes. All Ti-alloys exhibited a much better electrochemical behaviour: better Er and Ec and very high Eb. No significant differences of the above parameters existed between the Ti-alloys, except for Zr-containing alloys that showed better corrosion behaviour. A remarkable difference, however, was stated with respect to the electrolytes. NaCl 0.9% induced strong variations between the Ti-alloys. More homogeneous results were obtained with artificial saliva and RPMI medium, which induced a favourable Ec and an increased Ip. The presence of cells further decreased these values. The unbuffered NaCl solution seems to be less appropriate for the analysis of corrosion of metals. Additional in vitro biological assessments with CEM cell suspensions and MC3T3-E1 osteoblasts confirmed the advantages of the Ti(AlMoZr) and Ti(NbTaZr) alloys with an improved cell proliferation and vitality rate.

MC3T3-E1 proliferation and differentiation on biphasic mixtures of Mg substituted β-tricalcium phosphate and amorphous calcium phosphate

International Nuclear Information System (INIS)

Singh, Satish S.; Roy, Abhijit; Lee, Boeun E.; Banerjee, Ipsita; Kumta, Prashant N.

2014-01-01

A low temperature aqueous approach was used to synthesize nanocrystalline, high surface area Mg 2+ substituted β-tricalcium phosphate (β-TCMP) to assess its potential use as a synthetic bone graft substitute. X-ray diffraction indicated that β-TCMP was the predominant crystalline phase formed. However, thermal analysis revealed the presence of a secondary amorphous phase which increased with increasing Mg 2+ concentration. Further analysis by Rietveld refinement indicated that the level of ionic substitution of Ca 2+ by Mg 2+ was significantly lower than the amount of Mg 2+ measured using elemental analysis, confirming the formation of a Mg 2+ rich secondary amorphous phase. MC3T3-E1 proliferation on substrates prepared using β-TCMP was assessed using the MTT assay. In comparison to commercially available β-TCP, increased proliferation was observed on samples prepared with 50% Mg, despite elevated Mg 2+ and PO 4 3− concentrations in culture media. Alkaline phosphatase (ALP) activity and qRT-PCR were used to study the effect of varying Mg 2+ substitution on osteogenic differentiation. Cells cultured on β-TCMP substrates prepared with increased Mg 2+ concentrations expressed significantly increased levels of ALP activity and osteogenic genes such as, osteocalcin, collagen-1, and Runx2, in comparison to those cultured on commercially available β-TCP

WEHI-3 cells inhibit adipocyte differentiation in 3T3-L1 cells

Energy Technology Data Exchange (ETDEWEB)

Lai, Jing [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Liu, Gexiu [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Yan, Guoyao [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); He, Dongmei [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Zhou, Ying [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Chen, Shengting, E-mail: shengtingchen@sina.cn [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China)

2015-06-26

By investigating the anti-adipogenic effects of WEHI-3 cells – a murine acute myelomonocytic leukemia cell line – we sought to improve the efficiency of hematopoietic stem cell transplantation (HSCT). Analysis of Oil Red O staining and the expression of adipogenic genes, including PPARγ, C/EBPα, FAS and LPL, indicated that WEHI-3 cells significantly inhibited 3T3-L1 mouse preadipocyte cells from differentiating into adipocytes. In vivo, fat vacuoles in mice injected with WEHI-3 cells were also remarkably reduced in the murine bone marrow pimelosis model. Moreover, the key gene in the Rho signaling pathway, ROCKII, and the key gene in the Wnt signaling pathway, β-catenin, were both upregulated compared with the control group. siRNA-mediated knockdown of ROCKII and β-catenin reversed these WEHI-3-mediated anti-adipogenic effects. Taken together, these data suggest that WEHI-3 cells exert anti-adipogenic effects and that both ROCKII and β-catenin are involved in this process. - Highlights: • WEHI-3, an acute myelomonocytic leukemia cell line, inhibited 3T3-L1 preadipocyte from differentiating into adipocyte. • WEHI-3 cells can arrest 3T3-L1 cells in G0/G1 phase by secreting soluble factors and thus inhibit their proliferation. • WEHI-3 cells reduced bone marrow pimelosis in the murine model. • Both ROCKII and β-catenin were involved in the WEHI-3-mediated anti-adipogenic effects.

GPM GROUND VALIDATION OKLAHOMA CLIMATOLOGICAL SURVEY MESONET MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation Oklahoma Climatological Survey Mesonet MC3E data were collected during the Midlatitude Continental Convective Clouds Experiment (MC3E) in...

The role of monocytes and T cells in 1,25-dihydroxyvitamin D3 mediated inhibition of B cell function in vitro

DEFF Research Database (Denmark)

Müller, K; Heilmann, C; Poulsen, L K

1991-01-01

1,25-Dihydroxyvitamin D3 (1,25-(OH)2D3) inhibits immunoglobulin production by human mononuclear cells (MNC) in vitro. The present study was undertaken to evaluate the role of T cells and monocytes in 1,25-(OH)2D3 induced suppression of B cell functions. The synthetic vitamin D3 analogue MC 903...... was examined in parallel. 1,25-(OH)2D3 and MC 903 showed a dose-related inhibition of IgM, IgG and IgA plaque-forming cells in poke-weed mitogen (PWM) activated cultures of MNC. This effect was most likely mediated through impairment of T cell and monocyte functions. First, the inhibitory effect was seen after...

Fluid shear stress suppresses TNF-α-induced apoptosis in MC3T3-E1 cells: Involvement of ERK5-AKT-FoxO3a-Bim/FasL signaling pathways

Energy Technology Data Exchange (ETDEWEB)

Bin, Geng; Bo, Zhang; Jing, Wang; Jin, Jiang; Xiaoyi, Tan; Cong, Chen; Liping, An; Jinglin, Ma; Cuifang, Wang; Yonggang, Chen [The Second Hospital of Lanzhou University, #82 Cuiyingmen, Lanzhou, 730000 Gansu (China); Orthopaedics Key Laboratory of Gansu Province, Lanzhou, 730000 Gansu (China); Yayi, Xia, E-mail: xiayayildey@163.com [The Second Hospital of Lanzhou University, #82 Cuiyingmen, Lanzhou, 730000 Gansu (China); Orthopaedics Key Laboratory of Gansu Province, Lanzhou, 730000 Gansu (China)

2016-05-01

TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed the FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis. - Highlights: • Fluid shear stress inhibits osteoblast apoptosis induced by TNF-α. • Inhibition of ERK5 activity by transfection of ERK5 siRNA blocks FSS-mediated anti-apoptotic effect in osteoblast. • Activated ERK5-AKT-FoxO3a-Bim/FasL signaling pathways by FSS is required to protect osteoblast from apoptosis.

Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

International Nuclear Information System (INIS)

Takabe, Piia; Bart, Geneviève; Ropponen, Antti; Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna

2015-01-01

Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma

Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

Energy Technology Data Exchange (ETDEWEB)

Takabe, Piia, E-mail: piia.takabe@uef.fi [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Bart, Geneviève [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Ropponen, Antti [University of Eastern Finland, Institute of Clinical Medicine, 70211 Kuopio (Finland); Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland)

2015-09-10

Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma.

Irradiation of Polystyrene and Polypropylene to study NIH 3T3 fibroblasts adhesion

International Nuclear Information System (INIS)

Arbeitman, C.R.; Grosso, M.F. del; Ibanez, I.; Garcia Bermudez, G.; Duran, H.; Chappa, V.C.; Mazzei, R.; Behar, M.

2010-01-01

When polymers are irradiated with heavy ions new chemical groups are created in a few microns of the material. The irradiation changed the polarity and wettability on the surface so that could enhance the biocompatibility of the modified polymer. The study of chemistry and nanoscale topography of the biomaterial is important in determining its potential applications in medicine and biotechnology, because their strong influence on cell function, adhesion and proliferation. In this study, thin films of Polystyrene and Polypropylene samples were modified by irradiation with low energy ion beams (30-150 keV) and swift heavy ions both with various fluences and energies. The changes were evaluated with different methods. Adhesion of NIH 3T3 fibroblasts onto unirradiated and irradiated surfaces has been studied by in vitro techniques. The correlations between physicochemical properties as a function of different irradiations parameters were compared with cell adhesion on the modified polymer surface.

GPM GROUND VALIDATION NCAR CLOUD MICROPHYSICS PARTICLE PROBES MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation NCAR Cloud Microphysics Particle Probes MC3E dataset was collected during the Midlatitude Continental Convective Clouds Experiment (MC3E),...

EMMPRIN regulates β1 integrin-mediated adhesion through Kindlin-3 in human melanoma cells.

Science.gov (United States)

Delyon, Julie; Khayati, Farah; Djaafri, Ibtissem; Podgorniak, Marie-Pierre; Sadoux, Aurélie; Setterblad, Niclas; Boutalbi, Zineb; Maouche, Kamel; Maskos, Uwe; Menashi, Suzanne; Lebbé, Céleste; Mourah, Samia

2015-06-01

EMMPRIN is known to promote tumor invasion through extracellular matrix (ECM) degradation. Here we report that EMMPRIN can regulate melanoma cell adhesion to the ECM through an interaction with β1 integrin involving kindlin-3. In this study, EMMPRIN knockdown in the human melanoma cell line M10 using siRNA decreased cell invasion and significantly increased cell adhesion and spreading. A morphological change from a round to a spread shape was observed associated with enhanced phalloidin-labelled actin staining. In situ proximity ligation assay and co-immunoprecipitation revealed that EMMPRIN silencing increased the interaction of β1 integrin with kindlin-3, a focal adhesion protein. This was associated with an increase in β1 integrin activation and a decrease in the phosphorylation of the downstream integrin kinase FAK. Moreover, the expression at both the transcript and protein level of kindlin-3 and of β1 integrin was inversely regulated by EMMPRIN. EMMPRIN did not regulate either talin expression or its interaction with β1 integrin. These results are consistent with our in vivo demonstration that EMMPRIN inhibition increased β1 integrin activation and its interaction with kindlin-3. To conclude, these findings reveal a new role of EMMPRIN in tumor cell migration through ß1 integrin/kindlin-3-mediated adhesion pathway. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Kindlin-3 Is Essential for the Resting α4β1 Integrin-mediated Firm Cell Adhesion under Shear Flow Conditions.

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Lu, Ling; Lin, ChangDong; Yan, ZhanJun; Wang, Shu; Zhang, YouHua; Wang, ShiHui; Wang, JunLei; Liu, Cui; Chen, JianFeng

2016-05-06

Integrin-mediated rolling and firm cell adhesion are two critical steps in leukocyte trafficking. Integrin α4β1 mediates a mixture of rolling and firm cell adhesion on vascular cell adhesion molecule-1 (VCAM-1) when in its resting state but only supports firm cell adhesion upon activation. The transition from rolling to firm cell adhesion is controlled by integrin activation. Kindlin-3 has been shown to bind to integrin β tails and trigger integrin activation via inside-out signaling. However, the role of kindlin-3 in regulating resting α4β1-mediated cell adhesion is not well characterized. Herein we demonstrate that kindlin-3 was required for the resting α4β1-mediated firm cell adhesion but not rolling adhesion. Knockdown of kindlin-3 significantly decreased the binding of kindlin-3 to β1 and down-regulated the binding affinity of the resting α4β1 to soluble VCAM-1. Notably, it converted the resting α4β1-mediated firm cell adhesion to rolling adhesion on VCAM-1 substrates, increased cell rolling velocity, and impaired the stability of cell adhesion. By contrast, firm cell adhesion mediated by Mn(2+)-activated α4β1 was barely affected by knockdown of kindlin-3. Structurally, lack of kindlin-3 led to a more bent conformation of the resting α4β1. Thus, kindlin-3 plays an important role in maintaining a proper conformation of the resting α4β1 to mediate both rolling and firm cell adhesion. Defective kindlin-3 binding to the resting α4β1 leads to a transition from firm to rolling cell adhesion on VCAM-1, implying its potential role in regulating the transition between integrin-mediated rolling and firm cell adhesion. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Kindlin-3 Is Essential for the Resting α4β1 Integrin-mediated Firm Cell Adhesion under Shear Flow Conditions*

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Lu, Ling; Lin, ChangDong; Yan, ZhanJun; Wang, Shu; Zhang, YouHua; Wang, ShiHui; Wang, JunLei; Liu, Cui; Chen, JianFeng

2016-01-01

Integrin-mediated rolling and firm cell adhesion are two critical steps in leukocyte trafficking. Integrin α4β1 mediates a mixture of rolling and firm cell adhesion on vascular cell adhesion molecule-1 (VCAM-1) when in its resting state but only supports firm cell adhesion upon activation. The transition from rolling to firm cell adhesion is controlled by integrin activation. Kindlin-3 has been shown to bind to integrin β tails and trigger integrin activation via inside-out signaling. However, the role of kindlin-3 in regulating resting α4β1-mediated cell adhesion is not well characterized. Herein we demonstrate that kindlin-3 was required for the resting α4β1-mediated firm cell adhesion but not rolling adhesion. Knockdown of kindlin-3 significantly decreased the binding of kindlin-3 to β1 and down-regulated the binding affinity of the resting α4β1 to soluble VCAM-1. Notably, it converted the resting α4β1-mediated firm cell adhesion to rolling adhesion on VCAM-1 substrates, increased cell rolling velocity, and impaired the stability of cell adhesion. By contrast, firm cell adhesion mediated by Mn2+-activated α4β1 was barely affected by knockdown of kindlin-3. Structurally, lack of kindlin-3 led to a more bent conformation of the resting α4β1. Thus, kindlin-3 plays an important role in maintaining a proper conformation of the resting α4β1 to mediate both rolling and firm cell adhesion. Defective kindlin-3 binding to the resting α4β1 leads to a transition from firm to rolling cell adhesion on VCAM-1, implying its potential role in regulating the transition between integrin-mediated rolling and firm cell adhesion. PMID:26994136

GPM GROUND VALIDATION NOAA S-BAND PROFILER MINUTE DATA MC3E V1

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National Aeronautics and Space Administration — The GPM Ground Validation NOAA S-Band Profiler Minute Data MC3E dataset was gathered during the Midlatitude Continental Convective Clouds Experiment (MC3E) in...

GPM GROUND VALIDATION KICT NEXRAD MC3E V1

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National Aeronautics and Space Administration — The GPM Ground Validaiton KICT NEXRAD MC3E dataset was collected from April 22, 2011 to June 6, 2011 for the Midlatitude Continental Convective Clouds Experiment...

GPM GROUND VALIDATION CHILL RADAR MC3E V1

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National Aeronautics and Space Administration — The CHILL radar data for the Midlatitude Continental Convective Clouds Experiment (MC3E) held in Oklahoma were collected while the NASA ER-2 aircraft conducted a...

GPM GROUND VALIDATION PAWNEE RADAR MC3E V1

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National Aeronautics and Space Administration — The Pawnee radar data for the Midlatitude Continental Convective Clouds Experiment (MC3E) held in Oklahoma were collected on May 24, 2011 to support the CHILL radar...

CADM1 controls actin cytoskeleton assembly and regulates extracellular matrix adhesion in human mast cells.

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Elena P Moiseeva

Full Text Available CADM1 is a major receptor for the adhesion of mast cells (MCs to fibroblasts, human airway smooth muscle cells (HASMCs and neurons. It also regulates E-cadherin and alpha6beta4 integrin in other cell types. Here we investigated a role for CADM1 in MC adhesion to both cells and extracellular matrix (ECM. Downregulation of CADM1 in the human MC line HMC-1 resulted not only in reduced adhesion to HASMCs, but also reduced adhesion to their ECM. Time-course studies in the presence of EDTA to inhibit integrins demonstrated that CADM1 provided fast initial adhesion to HASMCs and assisted with slower adhesion to ECM. CADM1 downregulation, but not antibody-dependent CADM1 inhibition, reduced MC adhesion to ECM, suggesting indirect regulation of ECM adhesion. To investigate potential mechanisms, phosphotyrosine signalling and polymerisation of actin filaments, essential for integrin-mediated adhesion, were examined. Modulation of CADM1 expression positively correlated with surface KIT levels and polymerisation of cortical F-actin in HMC-1 cells. It also influenced phosphotyrosine signalling and KIT tyrosine autophosphorylation. CADM1 accounted for 46% of surface KIT levels and 31% of F-actin in HMC-1 cells. CADM1 downregulation resulted in elongation of cortical actin filaments in both HMC-1 cells and human lung MCs and increased cell rigidity of HMC-1 cells. Collectively these data suggest that CADM1 is a key adhesion receptor, which regulates MC net adhesion, both directly through CADM1-dependent adhesion, and indirectly through the regulation of other adhesion receptors. The latter is likely to occur via docking of KIT and polymerisation of cortical F-actin. Here we propose a stepwise model of adhesion with CADM1 as a driving force for net MC adhesion.

A protocadherin-cadherin-FLRT3 complex controls cell adhesion and morphogenesis.

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Xuejun Chen

2009-12-01

Full Text Available Paraxial protocadherin (PAPC and fibronectin leucine-rich domain transmembrane protein-3 (FLRT3 are induced by TGFbeta signaling in Xenopus embryos and both regulate morphogenesis by inhibiting C-cadherin mediated cell adhesion.We have investigated the functional and physical relationships between PAPC, FLRT3, and C-cadherin. Although neither PAPC nor FLRT3 are required for each other to regulate C-cadherin adhesion, they do interact functionally and physically, and they form a complex with cadherins. By itself PAPC reduces cell adhesion physiologically to induce cell sorting, while FLRT3 disrupts adhesion excessively to cause cell dissociation. However, when expressed together PAPC limits the cell dissociating and tissue disrupting activity of FLRT3 to make it effective in physiological cell sorting. PAPC counteracts FLRT3 function by inhibiting the recruitment of the GTPase RND1 to the FLRT3 cytoplasmic domain.PAPC and FLRT3 form a functional complex with cadherins and PAPC functions as a molecular "governor" to maintain FLRT3 activity at the optimal level for physiological regulation of C-cadherin adhesion, cell sorting, and morphogenesis.

Simultaneous use of two prostaglandin radioimmunoassays employing two antisera of differing specificity. II. Relative stability of prostaglandins E1, E2, and F1alpha in cell cultures of BALB/c 3T3 and SV3T3 mouse fibroblasts

International Nuclear Information System (INIS)

Ritzi, E.M.; Stylos, W.A.

1976-01-01

The relative stability of Prostaglandins (PGs) E1, E2 and F1α in cultures of BALB/c 3T3 and SV3T3 cells has been evaluated using 3 different approaches. First, total recovery of tritium in the ethyl acetate phase following incubation and extraction of PGF1α and PGE1 demonstrated greater stability for PGF1α (88.8 percent) than PGE1 (65.9 percent). Second, analysis of incubated, extracted, tritiated PGs by thin layer chromatography revealed decreases of up to 23 percent in the PGE zone following incubation of 3H-PGE1. With increasing time of incubation, decreases in the PGE zone were accompanied by increase in PGA-like compounds. 3H-PGF1α demonstrated greater stability, having greater than 90 percent recovery of the tritium in the PGF zone. A third approach to the assessment of PG stability in culture was the comparison of the production of individual PGs by radioimmunoassay (RIA). The data obtained by RIA indicated a lag in the increase of PGA and PGB, until an initial rise in PGE was noted, suggesting that PGA and PGB may be secondary products arising from PGE which exhibits only partial stability in culture. By employing two RIAs, one for total PGE and one for PGA and PGB, the composite determination PG [E + (A + B)] can be used to provide a more meaningful determination of PG production because of the instability of the PGs. On the other hand, individual determinations are helpful in assessing the stability of PGEs in cell cultures

GPM GROUND VALIDATION COMPOSITE SATELLITE OVERPASSES MC3E V1

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National Aeronautics and Space Administration — The GPM Ground Validation Composite Satellite Overpasses MC3E dataset provides satellite overpasses from the AQUA satellite during the Midlatitude Continental...

FTY720 and two novel butterfly derivatives exert a general anti-inflammatory potential by reducing immune cell adhesion to endothelial cells through activation of S1P(3) and phosphoinositide 3-kinase.

Science.gov (United States)

Imeri, Faik; Blanchard, Olivier; Jenni, Aurelio; Schwalm, Stephanie; Wünsche, Christin; Zivkovic, Aleksandra; Stark, Holger; Pfeilschifter, Josef; Huwiler, Andrea

2015-12-01

Sphingosine-1-phosphate (S1P) is a key lipid regulator of a variety of cellular responses including cell proliferation and survival, cell migration, and inflammatory reactions. Here, we investigated the effect of S1P receptor activation on immune cell adhesion to endothelial cells under inflammatory conditions. We show that S1P reduces both tumor necrosis factor (TNF)-α- and lipopolysaccharide (LPS)-stimulated adhesion of Jurkat and U937 cells to an endothelial monolayer. The reducing effect of S1P was reversed by the S1P1+3 antagonist VPC23019 but not by the S1P1 antagonist W146. Additionally, knockdown of S1P3, but not S1P1, by short hairpin RNA (shRNA) abolished the reducing effect of S1P, suggesting the involvement of S1P3. A suppression of immune cell adhesion was also seen with the immunomodulatory drug FTY720 and two novel butterfly derivatives ST-968 and ST-1071. On the molecular level, S1P and all FTY720 derivatives reduced the mRNA expression of LPS- and TNF-α-induced adhesion molecules including ICAM-1, VCAM-1, E-selectin, and CD44 which was reversed by the PI3K inhibitor LY294002, but not by the MEK inhibitor U0126.In summary, our data demonstrate a novel molecular mechanism by which S1P, FTY720, and two novel butterfly derivatives acted anti-inflammatory that is by suppressing gene transcription of various endothelial adhesion molecules and thereby preventing adhesion of immune cells to endothelial cells and subsequent extravasation.

Coculture with BJ fibroblast cells inhibits the adipogenesis and lipogenesis in 3T3-L1 cells

International Nuclear Information System (INIS)

Jeong, Hyun Jeong; Park, Sahng Wook; Kim, Hojeong; Park, Sang-Kyu; Yoon, Dojun

2010-01-01

Mouse or human fibroblasts are commonly used as feeder cells to prevent differentiation in stem or primary cell culture. In the present study, we addressed whether fibroblasts can affect the differentiation of adipocytes. We found that the differentiation of 3T3-L1 preadipocytes was strongly suppressed when the cells were cocultured with human fibroblast (BJ) cells. BrdU incorporation analysis indicated that mitotic clonal expansion, an early event required for 3T3-L1 cell adipogenesis, was not affected by BJ cells. The 3T3-L1 cell expression levels of peroxisome proliferator-activated receptor γ2, CCAAT/enhancer-binding protein alpha (C/EBPα), sterol regulatory element binding protein-1c, and Krueppel-like factor 15, but not those of C/EBPβ or C/EBPδ, were decreased by coculture with BJ cells. When mature 3T3-L1 adipocytes were cocultured with BJ cells, their lipid contents were significantly reduced, with decreased fatty acid synthase expression and increased phosphorylated form of acetyl-CoA carboxylase 1. Our data indicate that coculture with BJ fibroblast cells inhibits the adipogenesis of 3T3-L1 preadipocytes and decreases the lipogenesis of mature 3T3-L1 adipocytes.

GPM GROUND VALIDATION SATELLITE SIMULATED ORBITS MC3E V1

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National Aeronautics and Space Administration — The GPM Ground Validation Satellite Simulated Orbits MC3E dataset is available in the Orbital database , which takes account for the atmospheric profiles, the...

Tumor suppressor KAI1 affects integrin αvβ3-mediated ovarian cancer cell adhesion, motility, and proliferation

International Nuclear Information System (INIS)

Ruseva, Zlatna; Geiger, Pamina Xenia Charlotte; Hutzler, Peter; Kotzsch, Matthias; Luber, Birgit; Schmitt, Manfred; Gross, Eva; Reuning, Ute

2009-01-01

The tetraspanin KAI1 had been described as a metastasis suppressor in many different cancer types, a function for which associations of KAI1 with adhesion and signaling receptors of the integrin superfamily likely play a role. In ovarian cancer, integrin αvβ3 correlates with tumor progression and its elevation in vitro provoked enhanced cell adhesion accompanied by significant increases in cell motility and proliferation in the presence of its major ligand vitronectin. In the present study, we characterized integrin αvβ3-mediated tumor biological effects as a function of cellular KAI1 restoration and proved for the first time that KAI1, besides its already known physical crosstalk with β1-integrins, also colocalizes with integrin αvβ3. Functionally, elevated KAI1 levels drastically increased integrin αvβ3/vitronectin-dependent ovarian cancer cell adhesion. Since an intermediate level of cell adhesive strength is required for optimal cell migration, we next studied ovarian cancer cell motility as a function of KAI1 restoration. By time lapse video microscopy, we found impaired integrin αvβ3/vitronectin-mediated cell migration most probably due to strongly enhanced cellular immobilization onto the adhesion-supporting matrix. Moreover, KAI1 reexpression significantly diminished cell proliferation. These data strongly indicate that KAI1 may suppress ovarian cancer progression by inhibiting integrin αvβ3/vitronectin-provoked tumor cell motility and proliferation as important hallmarks of the oncogenic process.

Attachment and spreadout study of 3T3 cells onto PP track etched films

International Nuclear Information System (INIS)

Smolko, Eduardo; Mazzei, Ruben; Tadey, Daniel; Lombardo, Daniel

2001-01-01

Polymer surface modifications are obtained by the application of radiation treatments and other physico-chemical methods: fission fragment (ff) irradiation and etching. The biocompatibility of the surface is then observed by cell seeding and cell adhesion experiments. Approaches to improvement of the cell adhesion are obtained by different methods: for example, in PS, cell adhesion is improved after ion implantation; in PMMA, after bombarding the polymer, the surface is reconditioned with surfactants and proteins and in PVDF, cell adhesion is assayed on nuclear tracks membranes. In this work, we obtained important cell adhesion improvements in PP films by irradiation with swift heavy ions and subsequent etching of the nuclear tracks. We use BOPP (isotactic -25 μm thickness). Irrradiations were performed with a Cf-252 californium ff source. The source has a heavy ff and a light one, with 160-200 MeV energy divided among them corresponding to ff energies between 1 and 2 MeV/amu. A chemical etching procedure consisting of a solution of sulphuric acid and chromium three oxide at 85 deg. C was used. The 3T3 NIH fibroblast cell line was used for the cell adhesion experiment. Here we report for the first time, the results of a series of experiments by varying the ff fluence and the etching time showing that attachment and spreadout of cells are very much improved in this cell line according to the number of pores and the pore size

Cell-contact-dependent activation of CD4+ T cells by adhesion molecules on synovial fibroblasts.

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Mori, Masato; Hashimoto, Motomu; Matsuo, Takashi; Fujii, Takao; Furu, Moritoshi; Ito, Hiromu; Yoshitomi, Hiroyuki; Hirose, Jun; Ito, Yoshinaga; Akizuki, Shuji; Nakashima, Ran; Imura, Yoshitaka; Yukawa, Naoichiro; Yoshifuji, Hajime; Ohmura, Koichiro; Mimori, Tsuneyo

2017-05-01

To determine how cell-cell contact with synovial fibroblasts (SF) influence on the proliferation and cytokine production of CD4 +  T cells. Naïve CD4 +  T cells were cultured with SF from rheumatoid arthritis patients, stimulated by anti-CD3/28 antibody, and CD4 +  T cell proliferation and IFN-γ/IL-17 production were analyzed. To study the role of adhesion molecules, cell contact was blocked by transwell plate or anti-intracellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1(VCAM-1) antibody. To study the direct role of adhesion molecules for CD4 +  T cells, CD161 +  or CD161 - naïve CD4 +  T cells were stimulated on plastic plates coated by recombinant ICAM-1 or VCAM-1, and the source of IFN-γ/IL-17 were analyzed. SF enhanced naïve CD4 +  T cell proliferation and IFN-γ/IL-17 production in cell-contact and in part ICAM-1-/VCAM-1-dependent manner. Plate-coated ICAM-1 and VCAM-1 enhanced naïve CD4 +  T cell proliferation and IFN-γ production, while VCAM-1 efficiently promoting IL-17 production. CD161 +  naïve T cells upregulating LFA-1 and VLA-4 were the major source of IFN-γ/IL-17 upon interaction with ICAM-1/VCAM-1. CD4 +  T cells rapidly expand and secrete IFN-γ/IL-17 upon cell-contact with SF via adhesion molecules. Interfering with ICAM-1-/VCAM-1 may be beneficial for inhibiting RA synovitis.

MMSET deregulation affects cell cycle progression and adhesion regulons in t(4;14) myeloma plasma cells

Science.gov (United States)

Brito, Jose L.R.; Walker, Brian; Jenner, Matthew; Dickens, Nicholas J.; Brown, Nicola J.M.; Ross, Fiona M.; Avramidou, Athanasia; Irving, Julie A.E.; Gonzalez, David; Davies, Faith E.; Morgan, Gareth J.

2009-01-01

Background The recurrent immunoglobulin translocation, t(4;14)(p16;q32) occurs in 15% of multiple myeloma patients and is associated with poor prognosis, through an unknown mechanism. The t(4;14) up-regulates fibroblast growth factor receptor 3 (FGFR3) and multiple myeloma SET domain (MMSET) genes. The involvement of MMSET in the pathogenesis of t(4;14) multiple myeloma and the mechanism or genes deregulated by MMSET upregulation are still unclear. Design and Methods The expression of MMSET was analyzed using a novel antibody. The involvement of MMSET in t(4;14) myelomagenesis was assessed by small interfering RNA mediated knockdown combined with several biological assays. In addition, the differential gene expression of MMSET-induced knockdown was analyzed with expression microarrays. MMSET gene targets in primary patient material was analyzed by expression microarrays. Results We found that MMSET isoforms are expressed in multiple myeloma cell lines, being exclusively up-regulated in t(4;14)-positive cells. Suppression of MMSET expression affected cell proliferation by both decreasing cell viability and cell cycle progression of cells with the t(4;14) translocation. These findings were associated with reduced expression of genes involved in the regulation of cell cycle progression (e.g. CCND2, CCNG1, BRCA1, AURKA and CHEK1), apoptosis (CASP1, CASP4 and FOXO3A) and cell adhesion (ADAM9 and DSG2). Furthermore, we identified genes involved in the latter processes that were differentially expressed in t(4;14) multiple myeloma patient samples. Conclusions In conclusion, dysregulation of MMSET affects the expression of several genes involved in the regulation of cell cycle progression, cell adhesion and survival. PMID:19059936

T Cell Subset and Stimulation Strength-Dependent Modulation of T Cell Activation by Kv1.3 Blockers.

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Wai-Ping Fung-Leung

Full Text Available Kv1.3 is a voltage-gated potassium channel expressed on T cells that plays an important role in T cell activation. Previous studies have shown that blocking Kv1.3 channels in human T cells during activation results in reduced calcium entry, cytokine production, and proliferation. The aim of the present study was to further explore the effects of Kv1.3 blockers on the response of different human T cell subsets under various stimulation conditions. Our studies show that, unlike the immune suppressor cyclosporine A, the inhibitory effect of Kv1.3 blockers was partial and stimulation strength dependent, with reduced inhibitory efficacy on T cells under strengthened anti-CD3/CD28 stimulations. T cell responses to allergens including house dust mites and ragweed were partially reduced by Kv1.3 blockers. The effect of Kv1.3 inhibition was dependent on T cell subsets, with stronger effects on CCR7- effector memory compared to CCR7+ central memory CD4 T cells. Calcium entry studies also revealed a population of CD4 T cells resistant to Kv1.3 blockade. Activation of CD4 T cells was accompanied with an increase in Kv1.3 currents but Kv1.3 transcripts were found to be reduced, suggesting a posttranscriptional mechanism in the regulation of Kv1.3 activities. In summary, Kv1.3 blockers inhibit T cell activation in a manner that is highly dependent on the T cell identity and stimulation strength, These findings suggest that Kv1.3 blockers inhibit T cells in a unique, conditional manner, further refining our understanding of the therapeutic potential of Kv1.3 blockers.

The effect of porosity on cell ingrowth into accurately defined, laser-made, polylactide-based 3D scaffolds

Energy Technology Data Exchange (ETDEWEB)

Danilevicius, Paulius; Georgiadi, Leoni [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Pateman, Christopher J.; Claeyssens, Frederik [Kroto Research Institute, Department of Materials Science and Engineering, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); Chatzinikolaidou, Maria, E-mail: mchatzin@materials.uoc.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Department of Materials Science and Technology, University of Crete, PO Box 2208, 71303 Heraklion (Greece); Farsari, Maria, E-mail: mfarsari@iesl.forth.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece)

2015-05-01

Highlights: • We studied the porosity of laser-made 3D scaffolds on MC3T3-E1 pre-osteoblastic cells. • We made polylactide 3D scaffolds with pores 25–110 μm. - Abstract: The aim of this study is to demonstrate the accuracy required for the investigation of the role of solid scaffolds’ porosity in cell proliferation. We therefore present a qualitative investigation into the effect of porosity on MC3T3-E1 pre-osteoblastic cell ingrowth of three-dimensional (3D) scaffolds fabricated by direct femtosecond laser writing. The material we used is a purpose made photosensitive pre-polymer based on polylactide. We designed and fabricated complex, geometry-controlled 3D scaffolds with pore sizes ranging from 25 to 110 μm, representing porosities 70%, 82%, 86%, and 90%. The 70% porosity scaffolds did not support cell growth initially and in the long term. For the other porosities, we found a strong adhesion of the pre-osteoblastic cells from the first hours after seeding and a remarkable proliferation increase after 3 weeks and up to 8 weeks. The 86% porosity scaffolds exhibited a higher efficiency compared to 82% and 90%. In addition, bulk material degradation studies showed that the employed, highly-acrylated polylactide is degradable. These findings support the potential use of the proposed material and the scaffold fabrication technique in bone tissue engineering.

The Midlatitude Continental Convective Clouds Experiment (MC3E)

Energy Technology Data Exchange (ETDEWEB)

Jensen, Mark P.; Petersen, Walt A.; Bansemer, Aaron; Bharadwaj, Nitin; Carey, Larry; Cecil, D. J.; Collis, Scott M.; Del Genio, Anthony D.; Dolan, Brenda A.; Gerlach, J.; Giangrande, Scott; Heymsfield, Andrew J.; Heymsfield, Gerald; Kollias, Pavlos; Lang, T. J.; Nesbitt, Steve W.; Neumann, Andrea; Poellot, M. R.; Rutledge, Steven A.; Schwaller, Mathew R.; Tokay, Ali; Williams, C. R.; Wolff, D. B.; Xie, Shaocheng; Zipser, Edward J.

2016-10-18

The Midlatitude Continental Convective Clouds Experiment (MC3E), a field program jointly led by the U.S. Department of Energy’s Atmospheric Radiation Measurement program and the NASA Global Precipitation Measurement (GPM) Mission, was conducted in south-central Oklahoma during April – May 2011. MC3E science objectives were motivated by the need to improve understanding of midlatitude continental convective cloud system lifecycles, microphysics, and GPM precipitation retrieval algorithms. To achieve these objectives a multi-scale surface- and aircraft-based in situ and remote sensing observing strategy was employed. A variety of cloud and precipitation events were sampled during the MC3E, of which results from three deep convective events are highlighted. Vertical structure, air motions, precipitation drop-size distributions and ice properties were retrieved from multi-wavelength radar, profiler, and aircraft observations for an MCS on 11 May. Aircraft observations for another MCS observed on 20 May were used to test agreement between observed radar reflectivities and those calculated with forward-modeled reflectivity and microwave brightness temperatures using in situ particle size distributions and ice water content. Multi-platform observations of a supercell that occurred on 23 May allowed for an integrated analysis of kinematic and microphysical interactions. A core updraft of 25 ms-1 supported growth of hail and large rain drops. Data collected during the MC3E campaign is being used in a number of current and ongoing research projects and is available through the DOE ARM and NASA data archives.

Functional Characterization of MC1R-TUBB3 Intergenic Splice Variants of the Human Melanocortin 1 Receptor.

Directory of Open Access Journals (Sweden)

Cecilia Herraiz

Full Text Available The melanocortin 1 receptor gene (MC1R expressed in melanocytes is a major determinant of skin pigmentation. It encodes a Gs protein-coupled receptor activated by α-melanocyte stimulating hormone (αMSH. Human MC1R has an inefficient poly(A site allowing intergenic splicing with its downstream neighbour Tubulin-β-III (TUBB3. Intergenic splicing produces two MC1R isoforms, designated Iso1 and Iso2, bearing the complete seven transmembrane helices from MC1R fused to TUBB3-derived C-terminal extensions, in-frame for Iso1 and out-of-frame for Iso2. It has been reported that exposure to ultraviolet radiation (UVR might promote an isoform switch from canonical MC1R (MC1R-001 to the MC1R-TUBB3 chimeras, which might lead to novel phenotypes required for tanning. We expressed the Flag epitope-tagged intergenic isoforms in heterologous HEK293T cells and human melanoma cells, for functional characterization. Iso1 was expressed with the expected size. Iso2 yielded a doublet of Mr significantly lower than predicted, and impaired intracellular stability. Although Iso1- and Iso2 bound radiolabelled agonist with the same affinity as MC1R-001, their plasma membrane expression was strongly reduced. Decreased surface expression mostly resulted from aberrant forward trafficking, rather than high rates of endocytosis. Functional coupling of both isoforms to cAMP was lower than wild-type, but ERK activation upon binding of αMSH was unimpaired, suggesting imbalanced signaling from the splice variants. Heterodimerization of differentially labelled MC1R-001 with the splicing isoforms analyzed by co-immunoprecipitation was efficient and caused decreased surface expression of binding sites. Thus, UVR-induced MC1R isoforms might contribute to fine-tune the tanning response by modulating MC1R-001 availability and functional parameters.

Fluorescence lifetime imaging of lipids during 3T3-L1 cell differentiation

Science.gov (United States)

Song, Young Sik; Won, Young Jae; Lee, Sang-Hak; Kim, Dug Young

2014-03-01

Obesity is becoming a big health problem in these days. Since increased body weight is due to increased number and size of the triglyceride-storing adipocytes, many researchers are working on differentiation conditions and processes of adipocytes. Adipocytes also work as regulators of whole-body energy homeostasis by secreting several proteins that regulate processes as diverse as haemostasis, blood pressure, immune function, angiogenesis and energy balance. 3T3-L1 cells are widely used cell line for studying adipogenesis because it can differentiate into an adipocyte-like phenotype under appropriate conditions. In this paper, we propose an effective fluorescence lifetime imaging technique which can easily distinguish lipids in membrane and those in lipid droplets. Nile red dyes are attached to lipids in 3T3-L1 cells. Fluorescence lifetime images were taken for 2 week during differentiation procedure of 3T3-L1 cells into adipocytes. We used 488 nm pulsed laser with 5MHz repetition rate and emission wavelength is 520 nm of Nile Red fluorescent dye. Results clearly show that the lifetime of Nile red in lipid droplets are smaller than those in cell membrane. Our results suggest that fluorescence lifetime imaging can be a very powerful tool to monitor lipid droplet formation in adipocytes from 3T3-L1 cells.

Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

Science.gov (United States)

Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

2017-10-01

Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

Automated studies of radiation-induced changes in 3T3 cell motility and morphology

International Nuclear Information System (INIS)

Thurston, G.; Palcic, B.

1985-01-01

The most common endpoint in radiobiological studies is cell survival, as measured by colony forming ability. There is substantial experimental evidence that cell survival is related to the amount of radiation damage to the DNA. Radiation induces other changes in cell behaviour and morphology that may not be due to DNA damage alone. For example, low doses of radiation (<100 rads) were found to alter the ''phagokinetic tracks'' of moving 3T3 cells. They reported abnormal cell motility as demonstrated by a more random pattern of motion. 3T3 cells were also noted to show changes in morphology after exposure to x-rays. The fibroblast adhesion routine is disrupted by low doses of radiation (cell settling, microspike extension, lamellipodia flow, then cell spreading). An automated microscope system, DMIPS, is being used to automatically track 3T3 cells as they move and to correlate their movement with their morphology. An effort is being made to quantitate, for a large number of cells, the changes in 3T3 cell motility induced by radiation. The DMIPS procedure is compared to the gold dust technique

Deferoxamine immobilized poly(D,L-lactide) membrane via polydopamine adhesive coating: The influence on mouse embryo osteoblast precursor cells and human umbilical vein endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Li, Huihua [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Luo, Binghong, E-mail: tluobh@jnu.edu.cn [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Wen, Wei [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Zhou, Changren, E-mail: tcrz9@jnu.edu.cn [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Tian, Lingling [Center for Nanofibers & Nanotechnology, Department of Mechanical Engineering, National University of Singapore, Singapore 117576 (Singapore); Ramakrishna, Seeram [Center for Nanofibers & Nanotechnology, Department of Mechanical Engineering, National University of Singapore, Singapore 117576 (Singapore); Guangdong-Hongkong-Macau Institute of CNS Regeneration (GHMICR), Jinan University, Guangzhou 510632 (China)

2017-01-01

Osteogenesis and angiogenesis play the prominent role in the bone regeneration. In this study, deferoxamine (DFO), an induced agent for osteogenesis and angiogenesis, was modified onto the surface of poly(D,L-lactide) (PDLLA) membrane via a facile and convenient approach based on the self-polymerization of dopamine (DOPA). The surface composition, morphology, hydrophilicity and surface energy of the original and modified PDLLA membranes were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electronic microscopy (SEM), atomic force microscopy (AFM) and contact angle measurement. The surface roughness and hydrophilicity of the PDLLA membrane were obviously increased by introducing either the single polydopamine (PDOPA) or the dual layers of PDOPA and DFO. In vitro cells culture experiments indicated that both the PDLLA/PDOPA and PDLLA/PDOPA-DFO composite membranes were more beneficial to the attachment, proliferation and spreading of MC3T3-E1 cells and HUVECs compared to the original PDLLA membrane. The PDLLA/PDOPA-DFO membrane was supportive for the proliferation of both MC3T3-E1 cells and HUVECs, and especially for HUVECs. The results suggested that the as-prepared PDLLA/PDOPA-DFO composite can be expected to be used as a promising bone regenerative material with promoted angiogenesis. - Highlights: • DFO was conveniently immobilized on PDLLA membrane based on PDOPA adhesive layer. • Hydrophilicity of PDLLA membrane was improved by modification with PDOPA and DFO. • Modified membranes were more favorable to the growth of MC3T3-E1 cells and HUVECs. • DFO was supportive for the growth of two kinds of cells, especially for HUVECs.

Isolation of reovirus T3D mutants capable of infecting human tumor cells independent of junction adhesion molecule-A.

Directory of Open Access Journals (Sweden)

Diana J M van den Wollenberg

Full Text Available Mammalian Reovirus is a double-stranded RNA virus with a distinctive preference to replicate in and lyse transformed cells. On that account, Reovirus type 3 Dearing (T3D is clinically evaluated as oncolytic agent. The therapeutic efficacy of this approach depends in part on the accessibility of the reovirus receptor Junction Adhesion Molecule-A (JAM-A on the target cells. Here, we describe the isolation and characterization of reovirus T3D mutants that can infect human tumor cells independent of JAM-A. The JAM-A-independent (jin mutants were isolated on human U118MG glioblastoma cells, which do not express JAM-A. All jin mutants harbour mutations in the S1 segments close to the region that encodes the sialic acid-binding pocket in the shaft of the spike protein. In addition, two of the jin mutants encode spike proteins with a Q336R substitution in their head domain. The jin mutants can productively infect a wide range of cell lines that resist wt reovirus T3D infection, including chicken LMH cells, hamster CHO cells, murine endothelioma cells, human U2OS and STA-ET2.1 cells, but not primary human fibroblasts. The jin-mutants rely on the presence of sialic-acid residues on the cell surface for productive infection, as is evident from wheat germ agglutinin (WGA inhibition experiments, and from the jin-reovirus resistance of CHO-Lec2 cells, which have a deficiency of sialic-acids on their glycoproteins. The jin mutants may be useful as oncolytic agents for use in tumors in which JAM-A is absent or inaccessible.

ATF3 inhibits adipocyte differentiation of 3T3-L1 cells

International Nuclear Information System (INIS)

Jang, Min Kyung; Kim, Cho Hee; Seong, Je Kyung; Jung, Myeong Ho

2012-01-01

Highlights: ► Overexpression of ATF3 inhibits adipocyte differentiation in 3T3-L1 cells. ► Overexpression of ATF3 represses C/EBPα expression. ► ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. ► ATF3 may play a role in hypoxia-mediated inhibition of adipocyte differentiation. -- Abstract: ATF3 is a stress-adaptive gene that regulates proliferation or apoptosis under stress conditions. However, the role of ATF3 is unknown in adipocyte cells. Therefore, in this study, we investigated the functional role of ATF3 in adipocytes. Both lentivirus-mediated overexpression of ATF3 and stably-overexpressed ATF3 inhibited adipocyte differentiation in 3T3-L1 cells, as revealed by decreased lipid staining with oil red staining and reduction in adipogenic genes. Thapsigargin treatment and overexpression of ATF3 decreased C/EBPα transcript and repressed the activity of the 3.6-kb mouse C/EBPα promoter, demonstrating that ATF3 downregulates C/EBPα expression. Transfection studies using mutant constructs containing 5′-deletions in the C/EBPα promoter revealed that a putative ATF/CRE element, GGATGTCA, is located between −1921 and −1914. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. Both chemical hypoxia-mimetics or physical hypoxia led to reduce the C/EBPα mRNA and repress the promoter activity of the C/EBPα gene, whereas increase ATF3 mRNA, suggesting that ATF3 may contribute to the inhibition of adipocyte differentiation in hypoxia through downregulation of C/EBPα expression. Collectively, these results demonstrate that ATF3 represses the C/EBPα gene, resulting in inhibition of adipocyte differentiation, and thus plays a role in hypoxia-mediated inhibition of adipocyte differentiation.

The effect of cell passage on the susceptibility of BALB/3T3 clone A31-1-1 cells to 3-methylcholanthrene-induced morphological transformation.

Science.gov (United States)

Sheu, C W; Moreland, F M; Dunkel, V C

1987-01-01

The response of BALB/3T3 clone A31-1-1 cells to chemically induced morphological transformation was evaluated using 3-methylcholanthrene (MCA). Stock cultures were initiated from cryopreserved cells, grown in T25 flasks containing 5 ml of medium, and replated at subconfluency. Serially transferred cells were then subjected to transformation assay. After 24-hr seeding, cells were incubated 48 hr with MCA in a 5% CO2 incubator. They were then rinsed and incubated for an additional 4 weeks with twice weekly medium change. Type III foci were scored after fixation and staining with Giemsa. With serial passage from the frozen state, cells of passages 3-14 had a low level of spontaneous transformation; zero to 6 type III foci per 20 dishes were counted. In the MCA-treated cultures the number of transformed foci, however, increased with passage. Such passage-related sensitivity to MCA was demonstrated for cells cultured in two batches of sera: one from MA Bioproducts (Lot no. 2E052) and the other from Armour Pharmaceuticals (Lot no. Y65801). The passage-related increase in number of transformed foci was not related to doubling time, cloning efficiency, or MCA-induced growth inhibition.

Effect of fibronectin adsorption on osteoblastic cellular responses to hydroxyapatite and alumina

International Nuclear Information System (INIS)

Kawashita, Masakazu; Hasegawa, Maki; Kudo, Tada-aki; Kanetaka, Hiroyasu; Miyazaki, Toshiki; Hashimoto, Masami

2016-01-01

Initial cellular responses following implantation are important for inducing osteoconduction. We investigated cell adhesion, spreading, proliferation and differentiation of mouse MC3T3-E1 osteoblastic cells on untreated or fibronectin (Fn)-coated discs of hydroxyapatite (HAp) or alpha-type alumina (α-Al 2 O 3 ). Fn coating significantly enhanced adhesion and spreading of MC3T3-E1 cells on HAp, but did not affect MC3T3-E1 cell proliferation and differentiation on HAp or α-Al 2 O 3 . Fn-coated HAp likely does not stimulate pre-osteoblast cells to initiate the process of osteoconduction; however, Fn adsorption might affect the response of inflammatory cells to the implanted material or, in conjunction with other serum proteins, stimulate pre-osteoblast cell proliferation and differentiation. Further studies on the effect of serum proteins in cell culture and the efficacy of Fn-coated HAp and α-Al 2 O 3 in vivo are warranted. - Highlights: • We studied osteoblast-like MC3T3-E1 cell responses on fibronectin (Fn)-coated discs (HAp/α-Al 2 O 3 ). • Fn adsorption enhanced adhesion and spreading of MC3T3-E1 cells on HAp but not on α-Al 2 O 3 . • Fn adsorption hardly affected proliferation and differentiation of MC3T3-E1 cells on HAp and α-Al 2 O 3 . • Fn adsorption might stimulate osteoconduction on HAp along with other serum proteins.

Improving the Osteoblast Cell Adhesion on Electron Beam Controlled TiO2 Nanotubes

Directory of Open Access Journals (Sweden)

Sung Wook Yoon

2014-01-01

Full Text Available Here we investigate the osteogenesis and synostosis processes on the surface-modified TiO2 nanotubes via electron beam irradiation. The TiO2 nanotubes studied were synthesized by anodization process under different anodizing voltage. For the anodization voltage of 15, 20, and 25 V, TiO2 nanotubes with diameters of 59, 82, and 105 nm and length of 115, 276, and 310 nm were obtained, respectively. MC3T3-E1 osteoblast cell line was incubated on the TiO2 nanotubes to monitor the change in the cell adhesion before and after the electron beam irradiation. We observe that the electron beam irradiation affects the number of surviving osteoblast cells as well as the cultivation time. In particular, the high adhesion rate of 155% was obtained when the osteoblast cells were cultivated for 2 hours on the TiO2 nanotube, anodized under 20 V, and irradiated with 5,000 kGy of electron beam.

Covalent attachment of cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) to poly(etheretherketone) surface by tailored silanization layers technique

International Nuclear Information System (INIS)

Zheng, Yanyan; Xiong, Chengdong; Li, Xiaoyu; Zhang, Lifang

2014-01-01

Highlights: • The carbonyl groups on PEEK surface were effectively reduced to hydroxyl groups using sodium borohydride. • Silanization layers technique was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on hydroxylation-pretreated PEEK sheet surface by covalent chemical attachment. • XPS, surface profiler and water contact angle measurements proved the presence of GRGD on PEEK surface. • Osteoblast-like cells (MC3T3-E1) attachment and proliferation were improved effectively on GRGD-modified PEEK surface. - Abstract: Poly(etheretherketone) (PEEK) is a rigid semicrystalline polymer that combines excellent mechanical properties, broad chemical resistance and bone-like stiffness and is widely used in biomedical fields. However, PEEK is naturally bioinert, leading to limited biomedical applications, especially when a direct bone-implant osteointegration is desired. In this study, a three-step reaction procedure was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on the surface of PEEK sheet by covalent chemical attachment to favor cell adhesion and proliferation. First, hydroxylation-pretreated PEEK surfaces were silanized with 7-Oct-1-enyltrichlorosilane (OETS) in dry cyclohexane, resulting in a silanization layer with terminal ethenyl. Second, the terminal ethylenic double bonds of the silanization layer on PEEK surface were converted to carboxyl groups through acidic potassium manganate oxidation. Finally, GRGD was covalently attached by carbodiimide mediated condensation between the carboxyl on PEEK surface and amine presents in GRGD. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, surface profiler and water contact angle measurements were applied to characterize the modified surfaces. The effect of cells attachment and proliferation on each specimen was investigated. Pre-osteoblast cells (MC3T3-E1) attachment, spreading and proliferation

Covalent attachment of cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) to poly(etheretherketone) surface by tailored silanization layers technique

Energy Technology Data Exchange (ETDEWEB)

Zheng, Yanyan [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xiong, Chengdong [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); Li, Xiaoyu [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Zhang, Lifang, E-mail: zhanglfcioc@163.com [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China)

2014-11-30

Highlights: • The carbonyl groups on PEEK surface were effectively reduced to hydroxyl groups using sodium borohydride. • Silanization layers technique was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on hydroxylation-pretreated PEEK sheet surface by covalent chemical attachment. • XPS, surface profiler and water contact angle measurements proved the presence of GRGD on PEEK surface. • Osteoblast-like cells (MC3T3-E1) attachment and proliferation were improved effectively on GRGD-modified PEEK surface. - Abstract: Poly(etheretherketone) (PEEK) is a rigid semicrystalline polymer that combines excellent mechanical properties, broad chemical resistance and bone-like stiffness and is widely used in biomedical fields. However, PEEK is naturally bioinert, leading to limited biomedical applications, especially when a direct bone-implant osteointegration is desired. In this study, a three-step reaction procedure was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on the surface of PEEK sheet by covalent chemical attachment to favor cell adhesion and proliferation. First, hydroxylation-pretreated PEEK surfaces were silanized with 7-Oct-1-enyltrichlorosilane (OETS) in dry cyclohexane, resulting in a silanization layer with terminal ethenyl. Second, the terminal ethylenic double bonds of the silanization layer on PEEK surface were converted to carboxyl groups through acidic potassium manganate oxidation. Finally, GRGD was covalently attached by carbodiimide mediated condensation between the carboxyl on PEEK surface and amine presents in GRGD. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, surface profiler and water contact angle measurements were applied to characterize the modified surfaces. The effect of cells attachment and proliferation on each specimen was investigated. Pre-osteoblast cells (MC3T3-E1) attachment, spreading and proliferation

Cell Volume Regulation and Signaling in 3T3-L1 Pre-adipocytes and Adipocytes

DEFF Research Database (Denmark)

Eduardsen, Kathrine; Larsen, Susanne; Novak, Ivana

2011-01-01

Caveolae have been implicated in sensing of cell volume perturbations, yet evidence is still limited and findings contradictory. Here, we investigated the possible role of caveolae in cell volume regulation and volume sensitive signaling in an adipocyte system with high (3T3-L1 adipocytes......); intermediate (3T3-L1 pre-adipocytes); and low (cholesterol-depleted 3T3-L1 pre-adipocytes) caveolae levels. Using large-angle light scattering, we show that compared to pre-adipocytes, differentiated adipocytes exhibit several-fold increased rates of volume restoration following osmotic cell swelling (RVD......) and osmotic cell shrinkage (RVI), accompanied by increased swelling-activated taurine efflux. However, caveolin-1 distribution was not detectably altered after osmotic swelling or shrinkage, and caveolae integrity, as studied by cholesterol depletion or expression of dominant negative Cav-1, was not required...

GPM GROUND VALIDATION NASA ER-2 NAVIGATION DATA MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation NASA ER-2 Navigation Data MC3E dataset contains information recorded by an on board navigation recorder (NavRec). In addition to typical...

GPM GROUND VALIDATION NASA MICRO RAIN RADAR (MRR) MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation NASA Micro Rain Radar (MRR) MC3E dataset was collected by a Micro Rain Radar (MRR), which is a vertically pointing Doppler radar which...

Effect of fibronectin adsorption on osteoblastic cellular responses to hydroxyapatite and alumina

Energy Technology Data Exchange (ETDEWEB)

Kawashita, Masakazu, E-mail: m-kawa@ecei.tohoku.ac.jp [Graduate School of Biomedical Engineering, Tohoku University, Sendai 980-8579 (Japan); Hasegawa, Maki [Graduate School of Biomedical Engineering, Tohoku University, Sendai 980-8579 (Japan); Kudo, Tada-aki; Kanetaka, Hiroyasu [Graduate School of Dentistry, Tohoku University, Sendai 980-8575 (Japan); Miyazaki, Toshiki [Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu 808-0196 (Japan); Hashimoto, Masami [Japan Fine Ceramics Center, Nagoya 456-8587 (Japan)

2016-12-01

Initial cellular responses following implantation are important for inducing osteoconduction. We investigated cell adhesion, spreading, proliferation and differentiation of mouse MC3T3-E1 osteoblastic cells on untreated or fibronectin (Fn)-coated discs of hydroxyapatite (HAp) or alpha-type alumina (α-Al{sub 2}O{sub 3}). Fn coating significantly enhanced adhesion and spreading of MC3T3-E1 cells on HAp, but did not affect MC3T3-E1 cell proliferation and differentiation on HAp or α-Al{sub 2}O{sub 3}. Fn-coated HAp likely does not stimulate pre-osteoblast cells to initiate the process of osteoconduction; however, Fn adsorption might affect the response of inflammatory cells to the implanted material or, in conjunction with other serum proteins, stimulate pre-osteoblast cell proliferation and differentiation. Further studies on the effect of serum proteins in cell culture and the efficacy of Fn-coated HAp and α-Al{sub 2}O{sub 3}in vivo are warranted. - Highlights: • We studied osteoblast-like MC3T3-E1 cell responses on fibronectin (Fn)-coated discs (HAp/α-Al{sub 2}O{sub 3}). • Fn adsorption enhanced adhesion and spreading of MC3T3-E1 cells on HAp but not on α-Al{sub 2}O{sub 3}. • Fn adsorption hardly affected proliferation and differentiation of MC3T3-E1 cells on HAp and α-Al{sub 2}O{sub 3}. • Fn adsorption might stimulate osteoconduction on HAp along with other serum proteins.

The effects of BIG-3 on osteoblast differentiation are not dependent upon endogenously produced BMPs

International Nuclear Information System (INIS)

Gori, Francesca; Demay, Marie B.

2005-01-01

BMPs play an important role in both intramembranous and endochondral ossification. BIG-3, BMP-2-induced gene 3 kb, encodes a WD-40 repeat protein that accelerates the program of osteoblastic differentiation in vitro. To examine the potential interactions between BIG-3 and the BMP-2 pathway during osteoblastic differentiation, MC3T3-E1 cells stably transfected with BIG-3 (MC3T3E1-BIG-3), or with the empty vector (MC3T3E1-EV), were treated with noggin. Noggin treatment of pooled MC3T3E1-EV clones inhibited the differentiation-dependent increase in AP activity observed in the untreated MC3T3E1-EV clones but did not affect the increase in AP activity in the MC3T3E1-BIG-3 clones. Noggin treatment decreased the expression of Runx2 and type I collagen mRNAs and impaired mineralized matrix formation in MC3T3E1-EV clones but not in MC3T3E1-BIG-3 clones. To determine whether the actions of BIG-3 on osteoblast differentiation converged upon the BMP pathway or involved an alternate signaling pathway, Smad1 phosphorylation was examined. Basal phosphorylation of Smad1 was not altered in the MC3T3E1-BIG-3 clones. However, these clones did not exhibit the noggin-dependent decrease in phosphoSmad1 observed in the MC3T3E1-EV clones, nor did it decrease nuclear localization of phosphoSmad1. These observations suggest that BIG-3 accelerates osteoblast differentiation in MC3T3-E1 cells by inducing phosphorylation and nuclear translocation of Smad1 independently of endogenously produced BMPs

FoxP3+ regulatory T cells are distinct from leukemia cells in HTLV-1-associated adult T-cell leukemia.

Science.gov (United States)

Toulza, Frederic; Nosaka, Kisato; Takiguchi, Masafumi; Pagliuca, Tony; Mitsuya, Hiroaki; Tanaka, Yuetsu; Taylor, Graham P; Bangham, Charles R M

2009-11-15

Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATLL). It has been postulated that ATLL cells might act as regulatory T cells (T(regs)) which, in common with ATLL cells, express both CD25 and FoxP3, and so contribute to the severe immune suppression typical of ATLL. We report here that the frequency of CD25(+) cells varied independently of the frequency of FoxP3(+) cells in both a cross-sectional study and in a longitudinal study of 2 patients with chronic ATLL. Furthermore, the capacity of ATLL cells to suppress proliferation of heterologous CD4(+)CD25(-) cells correlated with the frequency of CD4(+) FoxP3(+) cells but was independent of CD25 expression. Finally, the frequency of CD4(+)FoxP3(+) cells was inversely correlated with the lytic activity of HTLV-1-specific CTLs in patients with ATLL. We conclude that ATLL is not a tumor of FoxP3(+) regulatory T cells, and that a population of FoxP3(+) cells distinct from ATLL cells has regulatory functions and may impair the cell-mediated immune response to HTLV-1 in patients with ATLL.

Doxycycline-regulated 3T3-L1 preadipocyte cell line with inducible, stable expression of adenoviral E4orf1 gene: a cell model to study insulin-independent glucose disposal.

Science.gov (United States)

Krishnapuram, Rashmi; Dhurandhar, Emily J; Dubuisson, Olga; Hegde, Vijay; Dhurandhar, Nikhil V

2013-01-01

Impaired glycemic control and excessive adiposity are major risk factors for Type 2 Diabetes mellitus. In rodent models, Ad36, a human adenovirus, improves glycemic control, independent of dietary fat intake or adiposity. It is impractical to use Ad36 for therapeutic action. Instead, we identified that E4orf1 protein of Ad36, mediates its anti-hyperglycemic action independent of insulin signaling. To further evaluate the therapeutic potential of E4orf1 to improve glycemic control, we established a stable 3T3-L1 cell system in which E4orf1 expression can be regulated. The development and characterization of this cell line is described here. Full-length adenoviral-36 E4orf1 cDNA obtained by PCR was cloned into a tetracycline responsive element containing vector (pTRE-Tight-E4orf1). Upon screening dozens of pTRE-Tight-E4orf1 clones, we identified the one with the highest expression of E4orf1 in response to doxycycline treatment. Furthermore, using this inducible system we characterized the ability of E4orf1 to improve glucose disposal in a time dependent manner. This stable cell line offers a valuable resource to carefully study the novel signaling pathways E4orf1 uses to enhance cellular glucose disposal independent of insulin.

Doxycycline-regulated 3T3-L1 preadipocyte cell line with inducible, stable expression of adenoviral E4orf1 gene: a cell model to study insulin-independent glucose disposal.

Directory of Open Access Journals (Sweden)

Rashmi Krishnapuram

Full Text Available Impaired glycemic control and excessive adiposity are major risk factors for Type 2 Diabetes mellitus. In rodent models, Ad36, a human adenovirus, improves glycemic control, independent of dietary fat intake or adiposity. It is impractical to use Ad36 for therapeutic action. Instead, we identified that E4orf1 protein of Ad36, mediates its anti-hyperglycemic action independent of insulin signaling. To further evaluate the therapeutic potential of E4orf1 to improve glycemic control, we established a stable 3T3-L1 cell system in which E4orf1 expression can be regulated. The development and characterization of this cell line is described here. Full-length adenoviral-36 E4orf1 cDNA obtained by PCR was cloned into a tetracycline responsive element containing vector (pTRE-Tight-E4orf1. Upon screening dozens of pTRE-Tight-E4orf1 clones, we identified the one with the highest expression of E4orf1 in response to doxycycline treatment. Furthermore, using this inducible system we characterized the ability of E4orf1 to improve glucose disposal in a time dependent manner. This stable cell line offers a valuable resource to carefully study the novel signaling pathways E4orf1 uses to enhance cellular glucose disposal independent of insulin.

βig-h3 Represses T-Cell Activation in Type 1 Diabetes.

Science.gov (United States)

Patry, Maeva; Teinturier, Romain; Goehrig, Delphine; Zetu, Cornelia; Ripoche, Doriane; Kim, In-San; Bertolino, Philippe; Hennino, Ana

2015-12-01

βig-h3/TGF-βi is a secreted protein capable of binding to both extracellular matrix and cells. Human genetic studies recently revealed that in the tgfbi gene encoding for βig-h3, three single nucleotide polymorphisms were significantly associated with type 1 diabetes (T1D) risk. Pancreatic islets express βig-h3 in physiological conditions, but this expression is reduced in β-cell insult in T1D. Since the integrity of islets is destroyed by autoimmune T lymphocytes, we thought to investigate the impact of βig-h3 on T-cell activation. We show here that βig-h3 inhibits T-cell activation markers as well as cytotoxic molecule production as granzyme B and IFN-γ. Furthermore, βig-h3 inhibits early T-cell receptor signaling by repressing the activation of the early kinase protein Lck. Moreover, βig-h3-treated T cells are unable to induce T1D upon transfer in Rag2 knockout mice. Our study demonstrates for the first time that T-cell activation is modulated by βig-h3, an islet extracellular protein, in order to efficiently avoid autoimmune response. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Strong adhesion by regulatory T cells induces dendritic cell cytoskeletal polarization and contact-dependent lethargy.

Science.gov (United States)

Chen, Jiahuan; Ganguly, Anutosh; Mucsi, Ashley D; Meng, Junchen; Yan, Jiacong; Detampel, Pascal; Munro, Fay; Zhang, Zongde; Wu, Mei; Hari, Aswin; Stenner, Melanie D; Zheng, Wencheng; Kubes, Paul; Xia, Tie; Amrein, Matthias W; Qi, Hai; Shi, Yan

2017-02-01

Dendritic cells are targeted by regulatory T (T reg) cells, in a manner that operates as an indirect mode of T cell suppression. In this study, using a combination of single-cell force spectroscopy and structured illumination microscopy, we analyze individual T reg cell-DC interaction events and show that T reg cells exhibit strong intrinsic adhesiveness to DCs. This increased DC adhesion reduces the ability of contacted DCs to engage other antigen-specific cells. We show that this unusually strong LFA-1-dependent adhesiveness of T reg cells is caused in part by their low calpain activities, which normally release integrin-cytoskeleton linkage, and thereby reduce adhesion. Super resolution imaging reveals that such T reg cell adhesion causes sequestration of Fascin-1, an actin-bundling protein essential for immunological synapse formation, and skews Fascin-1-dependent actin polarization in DCs toward the T reg cell adhesion zone. Although it is reversible upon T reg cell disengagement, this sequestration of essential cytoskeletal components causes a lethargic state of DCs, leading to reduced T cell priming. Our results reveal a dynamic cytoskeletal component underlying T reg cell-mediated DC suppression in a contact-dependent manner. © 2017 Chen et al.

Angiogenesis mediated by soluble forms of E-selectin and vascular cell adhesion molecule-1

Science.gov (United States)

Koch, Alisa E.; Halloran, Margaret M.; Haskell, Catherine J.; Shah, Manisha R.; Polverini, Peter J.

1995-08-01

ENDOTHELIAL adhesion molecules facilitate the entry of leukocytes into inflamed tissues. This in turn promotes neovascularization, a process central to the progression of rheumatoid arthritis, tumour growth and wound repair1. Here we test the hypothesis that soluble endothelial adhesion molecules promote angiogenesis2á¤-4. Human recombinant soluble E-selectin and soluble vascular cell adhesion molecule-1 induced chemotaxis of human endothelial cells in vitro and were angiogenic in rat cornea. Soluble E-selectin acted on endothelial cells in part through a sialyl Lewis-X-dependent mechanism, while soluble vascular cell adhesion molecule-1 acted on endothelial cells in part through a very late antigen (VLA)-4 dependent mechanism. The chemotactic activity of rheumatoid synovial fluid for endothelial cells, and also its angiogenic activity, were blocked by antibodies to either soluble E-selectin or soluble vascular cell adhesion molecule-1. These results suggest a novel function for soluble endothelial adhesion molecules as mediators of angiogenesis.

Phosphatidylcholine induces apoptosis of 3T3-L1 adipocytes

Directory of Open Access Journals (Sweden)

Li Hailan

2011-12-01

Full Text Available Abstract Background Phosphatidylcholine (PPC formulation is used for lipolytic injection, even though its mechanism of action is not well understood. Methods The viability of 3T3-L1 pre-adipocytes and differentiated 3T3-L1 cells was measured after treatment of PPC alone, its vehicle sodium deoxycholate (SD, and a PPC formulation. Western blot analysis was performed to examine PPC-induced signaling pathways. Results PPC, SD, and PPC formulation significantly decreased 3T3-L1 cell viability in a concentration-dependent manner. PPC alone was not cytotoxic to CCD-25Sk human fibroblasts at concentrations Conclusions PPC results in apoptosis of 3T3-L1 cells.

ZDHHC3 Tyrosine Phosphorylation Regulates Neural Cell Adhesion Molecule Palmitoylation

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Lievens, Patricia Marie-Jeanne; Kuznetsova, Tatiana; Kochlamazashvili, Gaga; Cesca, Fabrizia; Gorinski, Natalya; Galil, Dalia Abdel; Cherkas, Volodimir; Ronkina, Natalia; Lafera, Juri; Gaestel, Matthias

2016-01-01

The neural cell adhesion molecule (NCAM) mediates cell-cell and cell-matrix adhesion. It is broadly expressed in the nervous system and regulates neurite outgrowth, synaptogenesis, and synaptic plasticity. Previous in vitro studies revealed that palmitoylation of NCAM is required for fibroblast growth factor 2 (FGF2)-stimulated neurite outgrowth and identified the zinc finger DHHC (Asp-His-His-Cys)-containing proteins ZDHHC3 and ZDHHC7 as specific NCAM-palmitoylating enzymes. Here, we verified that FGF2 controlled NCAM palmitoylation in vivo and investigated molecular mechanisms regulating NCAM palmitoylation by ZDHHC3. Experiments with overexpression and pharmacological inhibition of FGF receptor (FGFR) and Src revealed that these kinases control tyrosine phosphorylation of ZDHHC3 and that ZDHHC3 is phosphorylated by endogenously expressed FGFR and Src proteins. By site-directed mutagenesis, we found that Tyr18 is an FGFR1-specific ZDHHC3 phosphorylation site, while Tyr295 and Tyr297 are specifically phosphorylated by Src kinase in cell-based and cell-free assays. Abrogation of tyrosine phosphorylation increased ZDHHC3 autopalmitoylation, enhanced interaction with NCAM, and upregulated NCAM palmitoylation. Expression of ZDHHC3 with tyrosine mutated in cultured hippocampal neurons promoted neurite outgrowth. Our findings for the first time highlight that FGFR- and Src-mediated tyrosine phosphorylation of ZDHHC3 modulates ZDHHC3 enzymatic activity and plays a role in neuronal morphogenesis. PMID:27247265

Aspergillus fumigatus Cell Wall α-(1,3)-Glucan Stimulates Regulatory T-Cell Polarization by Inducing PD-L1 Expression on Human Dendritic Cells.

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Stephen-Victor, Emmanuel; Karnam, Anupama; Fontaine, Thierry; Beauvais, Anne; Das, Mrinmoy; Hegde, Pushpa; Prakhar, Praveen; Holla, Sahana; Balaji, Kithiganahalli N; Kaveri, Srini V; Latgé, Jean-Paul; Aimanianda, Vishukumar; Bayry, Jagadeesh

2017-12-05

Human dendritic cell (DC) response to α-(1,3)-glucan polysaccharide of Aspergillus fumigatus and ensuing CD4+ T-cell polarization are poorly characterized. α-(1,3)-Glucan was isolated from A. fumigatus conidia and mycelia cell wall. For the analysis of polarization, DCs and autologous naive CD4+ T cells were cocultured. Phenotype of immune cells was analyzed by flow cytometry, and cytokines by enzyme-linked immunosorbent assay (ELISA). Blocking antibodies were used to dissect the role of Toll-like receptor 2 (TLR2) and programmed death-ligand 1 (PD-L1) in regulating α-(1,3)-glucan-mediated DC activation and T-cell responses. DCs from TLR2-deficient mice were additionally used to consolidate the findings. α-(1,3)-Glucan induced the maturation of DCs and was dependent in part on TLR2. "α-(1,3)-Glucan-educated" DCs stimulated the activation of naive T cells and polarized a subset of these cells into CD4+CD25+FoxP3+ regulatory T cells (Tregs). Mechanistically, Treg stimulation by α-(1,3)-glucan was dependent on the PD-L1 pathway that negatively regulated interferon-gamma (IFN-γ) secretion. Short α-(1,3)-oligosaccharides lacked the capacity to induce maturation of DCs but significantly blocked α-(1,3)-glucan-induced Treg polarization. PD-L1 dictates the balance between Treg and IFN-γ responses induced by α-(1,3)-glucan. Our data provide a rationale for the exploitation of immunotherapeutic approaches that target PD-1-PD-L1 to enhance protective immune responses to A. fumigatus infections. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

ATF3, an HTLV-1 bZip factor binding protein, promotes proliferation of adult T-cell leukemia cells

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Ohshima Koichi

2011-03-01

Full Text Available Abstract Background Adult T-cell leukemia (ATL is an aggressive malignancy of CD4+ T-cells caused by human T-cell leukemia virus type 1 (HTLV-1. The HTLV-1 bZIP factor (HBZ gene, which is encoded by the minus strand of the viral genome, is expressed as an antisense transcript in all ATL cases. By using yeast two-hybrid screening, we identified activating transcription factor 3 (ATF3 as an HBZ-interacting protein. ATF3 has been reported to be expressed in ATL cells, but its biological significance is not known. Results Immunoprecipitation analysis confirmed that ATF3 interacts with HBZ. Expression of ATF3 was upregulated in ATL cell lines and fresh ATL cases. Reporter assay revealed that ATF3 could interfere with the HTLV-1 Tax's transactivation of the 5' proviral long terminal repeat (LTR, doing so by affecting the ATF/CRE site, as well as HBZ. Suppressing ATF3 expression inhibited proliferation and strongly reduced the viability of ATL cells. As mechanisms of growth-promoting activity of ATF3, comparative expression profiling of ATF3 knockdown cells identified candidate genes that are critical for the cell cycle and cell death, including cell division cycle 2 (CDC2 and cyclin E2. ATF3 also enhanced p53 transcriptional activity, but this activity was suppressed by HBZ. Conclusions Thus, ATF3 expression has positive and negative effects on the proliferation and survival of ATL cells. HBZ impedes its negative effects, leaving ATF3 to promote proliferation of ATL cells via mechanisms including upregulation of CDC2 and cyclin E2. Both HBZ and ATF3 suppress Tax expression, which enables infected cells to escape the host immune system.

Modified salicylanilide and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivatives as novel inhibitors of osteoclast differentiation and bone resorption.

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Chen, Chun-Liang; Liu, Fei-Lan; Lee, Chia-Chung; Chen, Tsung-Chih; Ahmed Ali, Ahmed Atef; Sytwu, Huey-Kang; Chang, Deh-Ming; Huang, Hsu-Shan

2014-10-09

Inhibition of osteoclast formation is a potential strategy to prevent inflammatory bone resorption and to treat bone diseases. In the present work, the purpose was to discover modified salicylanilides and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivatives as potential antiosteoclastogenic agents. Their inhibitory effects on RANKL-induced osteoclastogenesis from RAW264.7 cells were evaluated by TRAP stain assay. The most potent compounds, 1d and 5d, suppressed RANKL-induced osteoclast formation and TRAP activity dose-dependently. The cytotoxicity assay on RAW264.7 cells suggested that the inhibition of osteoclastic bone resorption by these compounds did not result from their cytotoxicity. Moreover, both compounds downregulated RANKL-induced NF-κB and NFATc1 in the nucleus, suppressed the expression of osteoclastogenesis-related marker genes during osteoclastogenesis, and prevented osteoclastic bone resorption but did not impair osteoblast differentiation in MC3T3-E1. Therefore, these modified salicylanilides and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-diones could be potential lead compounds for the development of a new class of antiresorptive agents.

The fibronectin-binding integrins alpha5beta1 and alphavbeta3 differentially modulate RhoA-GTP loading, organization of cell matrix adhesions, and fibronectin fibrillogenesis

DEFF Research Database (Denmark)

Danen, Erik H J; Sonneveld, Petra; Brakebusch, Cord

2002-01-01

We have studied the formation of different types of cell matrix adhesions in cells that bind to fibronectin via either alpha5beta1 or alphavbeta3. In both cases, cell adhesion to fibronectin leads to a rapid decrease in RhoA activity. However, alpha5beta1 but not alphavbeta3 supports high levels ...... receptors expressed on a cell dictates the ability of fibronectin to stimulate RhoA-mediated organization of cell matrix adhesions.......We have studied the formation of different types of cell matrix adhesions in cells that bind to fibronectin via either alpha5beta1 or alphavbeta3. In both cases, cell adhesion to fibronectin leads to a rapid decrease in RhoA activity. However, alpha5beta1 but not alphavbeta3 supports high levels...... of RhoA activity at later stages of cell spreading, which are associated with a translocation of focal contacts to peripheral cell protrusions, recruitment of tensin into fibrillar adhesions, and fibronectin fibrillogenesis. Expression of an activated mutant of RhoA stimulates alphavbeta3-mediated...

Involvement of JAK2 upstream of the PI 3-kinase in cell-cell adhesion regulation by gastrin

International Nuclear Information System (INIS)

Ferrand, Audrey; Kowalski-Chauvel, Aline; Bertrand, Claudine; Pradayrol, Lucien; Fourmy, Daniel; Dufresne, Marlene; Seva, Catherine

2004-01-01

The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway has been implicated in cell transformation and proliferation. Besides aberrant cell proliferation, loss of cell-cell adhesion during epithelial-mesenchymal transition (EMT) is an important event which occurs during development of epithelial cancers. However, the role of JAK-dependent pathways in this process is not known. We analyzed the involvement of these pathways in the regulation of E-cadherin-dependent cell-cell adhesion by gastrin, a mitogenic factor for gastrointestinal (GI) tract. We identified JAK2/STAT3 as a new pathway in gastrin signaling. We demonstrated that JAK2 functions as an upstream mediator of the phosphatidylinositol 3 (PI 3)-kinase activity in gastrin signaling. Indeed, we observed a coprecipitation of both kinases and an inhibition of gastrin-induced PI 3-kinase activation when JAK2 activity is blocked. We also demonstrated that loss of cell-cell adhesion and the increase in cell motility induced by gastrin required the activation of JAK2 and the PI 3-kinase. Indeed, the modifications in localization of adherens junctions proteins and the migration, observed in gastrin-stimulated cells, were reversed by inhibition of both kinases. These results described the involvement of JAK2 in the modulation of cell-cell adhesion in epithelial cells. They support a possible role of JAK2 in the epithelial-mesenchymal transition which occurs during malignant development

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.

The role of kaempferol-induced autophagy on differentiation and mineralization of osteoblastic MC3T3-E1 cells.

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Kim, In-Ryoung; Kim, Seong-Eon; Baek, Hyun-Su; Kim, Bok-Joo; Kim, Chul-Hoon; Chung, In-Kyo; Park, Bong-Soo; Shin, Sang-Hun

2016-08-31

Kaempferol, a kind of flavonol, has been reported to possess various osteogenic biological activities, such as inhibiting bone resorption of osteoclasts and promoting the differentiation and mineralization of preosteoblasts. However, the precise cellular mechanism of action of kaempferol in osteogenesis is elusive. Autophagy is a major intracellular degradation system, which plays an important role in cell growth, survival, differentiation and homeostasis in mammals. Recent studies showed that autophagy appeared to be involved in the degradation of osteoclasts, osteoblasts and osteocytes, potentially pointing to a new pathogenic mechanism of bone homeostasis and bone marrow disease. The potential correlation between autophagy, osteogenesis and flavonoids is unclear. The present study verified that kaempferol promoted osteogenic differentiation and mineralization and that it elevated osteogenic gene expression based on alkaline phosphatase (ALP) activity, alizarin red staining and quantitative PCR. And then we found that kaempferol induced autophagy by acridine orange (AO) and monodansylcadaverine (MDC) staining and autophagy-related protein expression. The correlation between kaempferol-induced autophagy and the osteogenic process was confirmed by the autophagy inhibitor 3-methyladenine (3-MA). Kaempferol promoted the proliferation, differentiation and mineralization of osteoblasts at a concentration of 10 μM. Kaempferol showed cytotoxic properties at concentrations above 50 μM. Concentrations above 10 μM decreased ALP activity, whereas those up to 10 μM increased ALP activity. Kaempferol at concentrations up to 10 μM also increased the expression of the osteoblast- activated factors RUNX-2, osterix, BMP-2 and collagen I according to RT-PCR analyses. 10 μM or less, the higher of the concentration and over time, kaempferol promoted the activity of osteoblasts. Kaempferol induced autophagy. It also increased the expression of the autophagy-related factors

Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

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Dong, Yan; Hirane, Miku; Araki, Mutsumi [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

2014-04-04

Highlights: • LPA{sub 5} inhibits the cell growth and motile activities of 3T3 cells. • LPA{sub 5} suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA{sub 5} on the cell motile activities inhibited by LPA{sub 1} in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA{sub 5} in 3T3 cells. • LPA signaling via LPA{sub 5} acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA{sub 1}–LPA{sub 6}) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA{sub 1} inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA{sub 5} in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA{sub 1} and LPA{sub 5} on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA{sub 5} may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA{sub 1}.

Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

International Nuclear Information System (INIS)

Dong, Yan; Hirane, Miku; Araki, Mutsumi; Fukushima, Nobuyuki; Tsujiuchi, Toshifumi

2014-01-01

Highlights: • LPA 5 inhibits the cell growth and motile activities of 3T3 cells. • LPA 5 suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA 5 on the cell motile activities inhibited by LPA 1 in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA 5 in 3T3 cells. • LPA signaling via LPA 5 acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA 1 –LPA 6 ) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA 1 inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA 5 in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA 1 and LPA 5 on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA 5 may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA 1

CaV 3.1 and CaV 3.3 account for T-type Ca2+ current in GH3 cells

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M.A. Mudado

2004-06-01

Full Text Available T-type Ca2+ channels are important for cell signaling by a variety of cells. We report here the electrophysiological and molecular characteristics of the whole-cell Ca2+ current in GH3 clonal pituitary cells. The current inactivation at 0 mV was described by a single exponential function with a time constant of 18.32 ± 1.87 ms (N = 16. The I-V relationship measured with Ca2+ as a charge carrier was shifted to the left when we applied a conditioning pre-pulse of up to -120 mV, indicating that a low voltage-activated current may be present in GH3 cells. Transient currents were first activated at -50 mV and peaked around -20 mV. The half-maximal voltage activation and the slope factors for the two conditions are -35.02 ± 2.4 and 6.7 ± 0.3 mV (pre-pulse of -120 mV, N = 15, and -27.0 ± 0.97 and 7.5 ± 0.7 mV (pre-pulse of -40 mV, N = 9. The 8-mV shift in the activation mid-point was statistically significant (P < 0.05. The tail currents decayed bi-exponentially suggesting two different T-type Ca2+ channel populations. RT-PCR revealed the presence of a1G (CaV3.1 and a1I (CaV3.3 T-type Ca2+ channel mRNA transcripts.

GPM GROUND VALIDATION CONICAL SCANNING MILLIMETER-WAVE IMAGING RADIOMETER (COSMIR) MC3E V1

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National Aeronautics and Space Administration — The GPM Ground Validation Conical Scanning Millimeter-wave Imaging Radiometer (COSMIR) MC3E dataset used the Conical Scanning Millimeter-wave Imaging Radiometer...

Co-ordinate regulation of the cytoskeleton in 3T3 cells overexpressing thymosin-beta4.

Science.gov (United States)

Golla, R; Philp, N; Safer, D; Chintapalli, J; Hoffman, R; Collins, L; Nachmias, V T

1997-01-01

In several cell types, short-term increases in the concentration of the G-actin-sequestering peptide thymosin-beta4 (Tbeta4) cause the disassembly of F-actin bundles. To determine the extent of cell adaptability to these reductions in F-actin, we overexpressed Tbeta4 in NIH 3T3 cells. In cell lines with Tbeta4 levels twice those of vector controls, G-actin increased approximately twofold as expected. However, F-actin did not decrease as in short-term experiments but rather also increased approximately twofold so that the G-F ratio remained constant. Surprisingly, the cytoskeletal proteins myosin IIA, alpha-actinin, and tropomyosin also increased nearly twofold. These increases were specific; DNA, total protein, lactic dehydrogenase, profilin, and actin depolymerizing factor levels were unchanged in the overexpressing cells. The Tbeta4 lines spread more fully and adhered to the dish more strongly than vector controls; this altered phenotype correlated with a twofold increase in talin and alpha5-integrin and a nearly threefold increase in vinculin. Focal adhesions, detected by indirect immunofluorescence with antivinculin, were increased in size over the controls. Northern blotting showed that mRNAs for both beta-actin and vinculin were increased twofold in the overexpressing lines. We conclude that 1) NIH 3T3 cells adapt to increased levels of G-actin sequestered by increased Tbeta4 by increasing their total actin so that the F-actin/G-actin ratio remains constant; 2) these cells coordinately increase several cytoskeletal and adhesion plaque proteins; and 3) at least for actin and vinculin, this regulation is at the transcriptional level. We therefore propose that the proteins of this multimember interacting complex making up the actin-based cytoskeleton, are coordinately regulated by factors that control the expression of several proteins. The mechanism may bear similarities to the control of synthesis of another multimember interacting complex, the myofibril of

GPM GROUND VALIDATION NOAA S-BAND PROFILER ORIGINAL DWELL DATA MC3E V1

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National Aeronautics and Space Administration — The S-band Profiler Original Dwell dataset in the netCDF format was gathered during the Midlatitude Continental Convective Clouds Experiment (MC3E) in Oklahoma...

Microarray evaluation of EP4 receptor-mediated prostaglandin E2 suppression of 3T3-L1 adipocyte differentiation

International Nuclear Information System (INIS)

Sugimoto, Yukihiko; Tsuboi, Hiroaki; Okuno, Yasushi; Tamba, Shigero; Tsuchiya, Soken; Tsujimoto, Gozo; Ichikawa, Atsushi

2004-01-01

Prostaglandin E 2 (PGE 2 ) has been shown to negatively regulate adipogenesis. To explore to what extent PGE 2 inhibits the differentiation of cells to adipocytes and to examine whether its effect could be due to EP4 receptor signaling, we used microarrays to analyze the gene expression profiles of 3T3-L1 cells exposed to a differentiation cocktail supplemented with PGE 2 , AE1-329 (an EP4 agonist), or vehicle. The differentiation-associated responses in genes such as adipocytokines and enzymes related to lipid metabolism were largely weakened upon PGE 2 treatment. In particular, the expression of peroxisome proliferator activated receptor-γ and CCAAT/enhancer binding protein-α, genes playing a central role in adipogenesis, was greatly suppressed. PGE 2 appears to be ineffective to a subclass of insulin target genes such as hexokinase 2 and phosphofructokinase. Similar responses were produced in the differentiation-associated genes upon AE1-329 treatment. These results suggest that PGE 2 inhibits a crucial step of the adipocyte differentiation process by acting on the EP4 receptor in 3T3-L1 cells

Transcriptional activation of prostate specific homeobox gene NKX3-1 in subsets of T-cell lymphoblastic leukemia (T-ALL.

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Stefan Nagel

Full Text Available Homeobox genes encode transcription factors impacting key developmental processes including embryogenesis, organogenesis, and cell differentiation. Reflecting their tight transcriptional control, homeobox genes are often embedded in large non-coding, cis-regulatory regions, containing tissue specific elements. In T-cell acute lymphoblastic leukemia (T-ALL homeobox genes are frequently deregulated by chromosomal aberrations, notably translocations adding T-cell specific activatory elements. NKX3-1 is a prostate specific homeobox gene activated in T-ALL patients expressing oncogenic TAL1 or displaying immature T-cell characteristics. After investigating regulation of NKX3-1 in primary cells and cell lines, we report its ectopic expression in T-ALL cells independent of chromosomal rearrangements. Using siRNAs and expression profiling, we exploited NKX3-1 positive T-ALL cell lines as tools to investigate aberrant activatory mechanisms. Our data confirmed NKX3-1 activation by TAL1/GATA3/LMO and identified LYL1 as an alternative activator in immature T-ALL cells devoid of GATA3. Moreover, we showed that NKX3-1 is directly activated by early T-cell homeodomain factor MSX2. These activators were regulated by MLL and/or by IL7-, BMP4- and IGF2-signalling. Finally, we demonstrated homeobox gene SIX6 as a direct leukemic target of NKX3-1 in T-ALL. In conclusion, we identified three major mechanisms of NKX3-1 regulation in T-ALL cell lines which are represented by activators TAL1, LYL1 and MSX2, corresponding to particular T-ALL subtypes described in patients. These results may contribute to the understanding of leukemic transcriptional networks underlying disturbed T-cell differentiation in T-ALL.

A novel regulatory function of sweet taste-sensing receptor in adipogenic differentiation of 3T3-L1 cells.

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Yosuke Masubuchi

Full Text Available BACKGROUND: Sweet taste receptor is expressed not only in taste buds but also in nongustatory organs such as enteroendocrine cells and pancreatic beta-cells, and may play more extensive physiological roles in energy metabolism. Here we examined the expression and function of the sweet taste receptor in 3T3-L1 cells. METHODOLOGY/PRINCIPAL FINDINGS: In undifferentiated preadipocytes, both T1R2 and T1R3 were expressed very weakly, whereas the expression of T1R3 but not T1R2 was markedly up-regulated upon induction of differentiation (by 83.0 and 3.8-fold, respectively at Day 6. The α subunits of Gs (Gαs and G14 (Gα14 but not gustducin were expressed throughout the differentiation process. The addition of sucralose or saccharin during the first 48 hours of differentiation considerably reduced the expression of peroxisome proliferator activated receptor γ (PPARγ and CCAAT/enhancer-binding protein α (C/EBPα at Day 2, the expression of aP2 at Day 4 and triglyceride accumulation at Day 6. These anti-adipogenic effects were attenuated by short hairpin RNA-mediated gene-silencing of T1R3. In addition, overexpression of the dominant-negative mutant of Gαs but not YM-254890, an inhibitor of Gα14, impeded the effects of sweeteners, suggesting a possible coupling of Gs with the putative sweet taste-sensing receptor. In agreement, sucralose and saccharin increased the cyclic AMP concentration in differentiating 3T3-L1 cells and also in HEK293 cells heterologously expressing T1R3. Furthermore, the anti-adipogenic effects of sweeteners were mimicked by Gs activation with cholera toxin but not by adenylate cyclase activation with forskolin, whereas small interfering RNA-mediated knockdown of Gαs had the opposite effects. CONCLUSIONS: 3T3-L1 cells express a functional sweet taste-sensing receptor presumably as a T1R3 homomer, which mediates the anti-adipogenic signal by a Gs-dependent but cAMP-independent mechanism.

Nebivolol stimulates mitochondrial biogenesis in 3T3-L1 adipocytes

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Huang, Chenglin; Chen, Dongrui; Xie, Qihai [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Vascular Biology, Department of Hypertension, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025 (China); Yang, Ying, E-mail: yangying_sh@yahoo.com [Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Shanghai Clinical Center for Endocrine and Metabolic Diseases, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025 (China); Shen, Weili, E-mail: weili_shen@hotmail.com [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Vascular Biology, Department of Hypertension, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025 (China)

2013-08-16

Highlights: •Nebivolol may act as a partial agonist of β3-adrenergic receptor (AR). •Nebivolol stimulates mitochondrial DNA replication and protein expression. •Nebivolol promotes mitochondrial synthesis via activation of eNOS by β3-AR. -- Abstract: Nebivolol is a third-generation β-adrenergic receptor (β-AR) blocker with additional beneficial effects, including the improvement of lipid and glucose metabolism in obese individuals. However, the underlying mechanism of nebivolol’s role in regulating the lipid profile remains largely unknown. In this study, we investigated the role of nebivolol in mitochondrial biogenesis in 3T3-L1 adipocytes. Exposure of 3T3-L1 cells to nebivolol for 24 h increased mitochondrial DNA copy number, mitochondrial protein levels and the expression of transcription factors involved in mitochondrial biogenesis, including PPAR-γ coactivator-1α (PGC-1α), Sirtuin 3 (Sirt3), mitochondrial transcription factor A (Tfam) and nuclear related factor 1 (Nrf1). These changes were accompanied by an increase in oxygen consumption and in the expression of genes involved in fatty acid oxidation and antioxidant enzymes in 3T3-L1 adipocytes, including nebivolol-induced endothelial nitric oxide synthase (eNOS), as well as an increase in the formation of cyclic guanosine monophosphate (cGMP). Pretreatment with NG-nitro-L-arginine methyl ester (l-NAME) attenuated nebivolol-induced mitochondrial biogenesis, as did the soluble guanylate cyclase inhibitor, ODQ. Treatment with nebivolol and β3-AR blocker SR59230A markedly attenuated PGC-1α, Sirt3 and manganese superoxide dismutase (MnSOD) protein levels in comparison to treatment with nebivolol alone. These data indicate that the mitochondrial synthesis and metabolism in adipocytes that is promoted by nebivolol is primarily mediated through the eNOS/cGMP-dependent pathway and is initiated by the activation of β3-AR receptors.

Andrographolide inhibits adipogenesis of 3T3-L1 cells by suppressing C/EBPβ expression and activation

International Nuclear Information System (INIS)

Chen, Ching-Chu; Chuang, Wei-Ting; Lin, Ai-Hsuan; Tsai, Chia-Wen; Huang, Chin-Shiu; Chen, Yun-Ting; Chen, Haw-Wen; Lii, Chong-Kuei

2016-01-01

Andrographolide, a diterpenoid, is the most abundant terpenoid in Andrographis paniculata, a popular Chinese herbal medicine. Andrographolide displays diverse biological activities including hypoglycemia, hypolipidemia, anti-inflammation, and anti-tumorigenesis. Recent evidence indicates that andrographolide displays anti-obesity property by inhibiting lipogenic gene expression, however, the underlying mechanisms remain to be elucidated. In this study, the effects of andrographolide on transcription factor cascade and mitotic clonal expansion in 3T3-L1 preadipocyte differentiation into adipocyte were determined. Andrographolide dose-dependently (0–15 μM) inhibited CCAAT/enhancer-binding protein α (C/EBPα) and C/EBPβ mRNA and protein expression as well as peroxisome proliferator-activated receptor γ (PPARγ) protein level during the adipogenesis of 3T3-L1 cells. Concomitantly, fatty acid synthase and stearoyl-CoA desaturase expression and lipid accumulation were attenuated by andrographolide. Oil-red O staining further showed that the first 48 h after the initiation of differentiation was critical for andrographolide inhibition of adipocyte formation. Andrographolide inhibited the phosphorylation of PKA and the activation of cAMP response element-binding protein (CREB) in response to a differentiation cocktail, which led to attenuated C/EBPβ expression. In addition, ERK and GSK3β-dependent C/EBPβ phosphorylation was attenuated by andrographolide. Moreover, andrographolide suppressed cyclin A, cyclin E, and CDK2 expression and impaired the progression of mitotic clonal expansion (MCE) by arresting the cell cycle at the Go/G1 phase. Taken together, these results indicate that andrographolide has a potent anti-obesity action by inhibiting PKA-CREB-mediated C/EBPβ expression as well as C/EBPβ transcriptional activity, which halts MCE progression and attenuates C/EBPα and PPARγ expression. - Highlights: • Andrographolide is a diterpenoid phytochemical. �

Andrographolide inhibits adipogenesis of 3T3-L1 cells by suppressing C/EBPβ expression and activation

Energy Technology Data Exchange (ETDEWEB)

Chen, Ching-Chu [Division of Endocrinology and Metabolism, Department of Medicine, China Medical University Hospital, Taichung, Taiwan (China); Division of Endocrinology and Metabolism, Department of Chinese Medicine, China Medical University, China Medical University, Taichung, Taiwan (China); Chuang, Wei-Ting; Lin, Ai-Hsuan; Tsai, Chia-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Huang, Chin-Shiu [Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Chen, Yun-Ting [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Chen, Haw-Wen, E-mail: chenhw@mail.cmu.edu.tw [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Lii, Chong-Kuei, E-mail: cklii@mail.cmu.edu.tw [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan (China)

2016-09-15

Andrographolide, a diterpenoid, is the most abundant terpenoid in Andrographis paniculata, a popular Chinese herbal medicine. Andrographolide displays diverse biological activities including hypoglycemia, hypolipidemia, anti-inflammation, and anti-tumorigenesis. Recent evidence indicates that andrographolide displays anti-obesity property by inhibiting lipogenic gene expression, however, the underlying mechanisms remain to be elucidated. In this study, the effects of andrographolide on transcription factor cascade and mitotic clonal expansion in 3T3-L1 preadipocyte differentiation into adipocyte were determined. Andrographolide dose-dependently (0–15 μM) inhibited CCAAT/enhancer-binding protein α (C/EBPα) and C/EBPβ mRNA and protein expression as well as peroxisome proliferator-activated receptor γ (PPARγ) protein level during the adipogenesis of 3T3-L1 cells. Concomitantly, fatty acid synthase and stearoyl-CoA desaturase expression and lipid accumulation were attenuated by andrographolide. Oil-red O staining further showed that the first 48 h after the initiation of differentiation was critical for andrographolide inhibition of adipocyte formation. Andrographolide inhibited the phosphorylation of PKA and the activation of cAMP response element-binding protein (CREB) in response to a differentiation cocktail, which led to attenuated C/EBPβ expression. In addition, ERK and GSK3β-dependent C/EBPβ phosphorylation was attenuated by andrographolide. Moreover, andrographolide suppressed cyclin A, cyclin E, and CDK2 expression and impaired the progression of mitotic clonal expansion (MCE) by arresting the cell cycle at the Go/G1 phase. Taken together, these results indicate that andrographolide has a potent anti-obesity action by inhibiting PKA-CREB-mediated C/EBPβ expression as well as C/EBPβ transcriptional activity, which halts MCE progression and attenuates C/EBPα and PPARγ expression. - Highlights: • Andrographolide is a diterpenoid phytochemical. �

The effect of myostatin on proliferation and lipid accumulation in 3T3-L1 preadipocytes.

Science.gov (United States)

Zhu, Hui Juan; Pan, Hui; Zhang, Xu Zhe; Li, Nai Shi; Wang, Lin Jie; Yang, Hong Bo; Gong, Feng Ying

2015-06-01

Myostatin is a critical negative regulator of skeletal muscle development, and has been reported to be involved in the progression of obesity and diabetes. In the present study, we explored the effects of myostatin on the proliferation and differentiation of 3T3-L1 preadipocytes by using 3-[4,5-dimethylthiazol-2-yl] 2,5-diphenyl tetrazolium bromide spectrophotometry, intracellular triglyceride (TG) assays, and real-time quantitative RT-PCR methods. The results indicated that recombinant myostatin significantly promoted the proliferation of 3T3-L1 preadipocytes and the expression of proliferation-related genes, including Cyclin B2, Cyclin D1, Cyclin E1, Pcna, and c-Myc, and IGF1 levels in the medium of 3T3-L1 were notably upregulated by 35.2, 30.5, 20.5, 33.4, 51.2, and 179% respectively (all Pmyostatin-treated 3T3-L1 cells. Meanwhile, the intracellular lipid content of myostatin-treated cells was notably reduced as compared with the non-treated cells. Additionally, the mRNA levels of Pparγ, Cebpα, Gpdh, Dgat, Acs1, Atgl, and Hsl were significantly downregulated by 22-76% in fully differentiated myostatin-treated adipocytes. Finally, myostatin regulated the mRNA levels and secretion of adipokines, including Adiponectin, Resistin, Visfatin, and plasminogen activator inhibitor-1 (PAI-1) in 3T3-L1 adipocytes (all Pmyostatin promoted 3T3-L1 proliferation by increasing the expression of cell-proliferation-related genes and by stimulating IGF1 secretion. Myostatin inhibited 3T3-L1 adipocyte differentiation by suppressing Pparγ and Cebpα expression, which consequently deceased lipid accumulation in 3T3-L1 cells by inhibiting the expression of critical lipogenic enzymes and by promoting the expression of lipolytic enzymes. Finally, myostatin modulated the expression and secretion of adipokines in fully differentiated 3T3-L1 adipocytes. © 2015 Society for Endocrinology.

Molecular mechanism of 9-cis-retinoic acid inhibition of adipogenesis in 3T3-L1 cells

International Nuclear Information System (INIS)

Sagara, Chiaki; Takahashi, Katsuhiko; Kagechika, Hiroyuki; Takahashi, Noriko

2013-01-01

Highlights: ► We examined the effects of 9-cis-RA on adipogenesis in mouse preadipocyte 3T3-L1. ► 9-cis-RA inhibited lipid accumulation in adipogenetically-induced 3T3-L1 cells. ► A RXR pan-antagonist suppressed the inhibitory effects of 9-cis-RA on adipogenesis. ► This antagonist had no effects on RXRα and PPARγ levels in 9-cis-RA-treated cells. ► 9-cis-RA-induced decrease in both RXRα and PPARγ was independent of RXR activation. -- Abstract: Retinoic acid (RA) signaling is mediated by specific nuclear hormone receptors. Here we examined the effects of 9-cis-RA on adipogenesis in mouse preadipocyte 3T3-L1 cells. 9-cis-RA inhibits the lipid accumulation of adipogenetically induced 3T3-L1 cells. The complex of retinoid X receptor α (RXRα) with peroxisome proliferator-activated receptor γ (PPARγ) is a major transcription factor in the process of adipogenesis, and the levels of these molecules were decreased by 9-cis-RA treatment. A RXR pan-antagonist suppressed 9-cis-RA’s inhibitory effects on adipogenesis, but not on the intracellular levels of both RXRα and PPARγ. These results suggest that 9-cis-RA could inhibit adipogenesis by activating RXR, and decrease both RXR and PPARγs levels in a RXR activation-independent manner

Prostate cancer cells induce osteoblastic differentiation via semaphorin 3A.

Science.gov (United States)

Liu, Fuzhou; Shen, Weiwei; Qiu, Hao; Hu, Xu; Zhang, Chao; Chu, Tongwei

2015-03-01

Prostate cancer metastasis to bone is the second most commonly diagnosed malignant disease among men worldwide. Such metastatic disease is characterized by the presence of osteoblastic bone lesions, and is associated with high rates of mortality. However, the various mechanisms involved in prostate cancer-induced osteoblastic differentiation have not been fully explored. Semaphorin 3A (Sema 3A) is a newly identified regulator of bone metabolism which stimulates differentiation of pre-osteoblastic cells under physiological conditions. We investigated in this study whether prostate cancer cells can mediate osteoblastic activity through Sema 3A. We cultured osteoprogenitor MC3T3-E1 cells in prostate cancer-conditioned medium, and analyzed levels of Sema 3A protein in diverse prostate cancer cell lines to identify cell lines in which Sema 3A production showed a positive correlation with osteo-stimulation. C4-2 cells were stably transfected with Sema 3A short hairpin RNA to further determine whether Sema 3A contributes to the ability of C4-2 cells to induce osteoblastic differentiation. Down-regulation of Sema 3A expression decreased indicators of C4-2 CM-induced osteoblastic differentiation, including alkaline phosphatase production and mineralization. Additionally, silencing or neutralizing Sema 3A in C4-2 cells resulted in diminished β-catenin expression in osteogenitor MC3T3-E1 cells. Our results suggest that prostate cancer-induced osteoblastic differentiation is at least partially mediated by Sema 3A, and may be regulated by the β-catenin signalling pathway. Sema 3A may represent a novel target for treatment of prostate cancer-induced osteoblastic lesions. © 2014 Wiley Periodicals, Inc.

Overexpression of α-catenin increases osteoblastic differentiation in mouse mesenchymal C3H10T1/2 cells

International Nuclear Information System (INIS)

Kim, Dohee; Yang, Jae-Yeon; Shin, Chan Soo

2009-01-01

α- and β-Catenin link cadherins to the actin-based cytoskeleton at adherens junctions and regulate cell-cell adhesion. Although roles of cadherins and canonical Wnt-/β-catenin-signaling in osteoblastic differentiation have been extensively studied, the role of α-catenin is not known. Murine embryonic mesenchymal stem cells, C3H10T1/2 cells, were transduced with retrovirus encoding α-catenin (MSCV-α-catenin-HA-GFP). In the presence of Wnt-3A conditioned medium or osteogenic medium (β-glycerol phosphate and ascorbic acid), cells overexpressing α-catenin showed enhanced osteoblastic differentiation as measured by alkaline phosphatase (ALP) staining and ALP activity assay compared to cells transduced with empty virus (MSCV-GFP). In addition, mRNA expression of osteocalcin and Runx2 was significantly increased compared to control. Cell aggregation assay revealed that α-catenin overexpression has significantly increased cell-cell aggregation. However, cellular β-catenin levels (total, cytoplasmic-nuclear ratio) and β-catenin-TCF/LEF transcriptional activity did not change by overexpression of α-catenin. Knock-down of α-catenin using siRNA decreased osteoblastic differentiation as measured by ALP assay. These results suggest that α-catenin overexpression increases osteoblastic differentiation by increasing cell-cell adhesion rather than Wnt-/β-catenin-signaling.

Correlation between E-cadherin-regulated cell adhesion and human osteosarcoma MG-63 cell anoikis.

Science.gov (United States)

Lin, Ding-Sheng; Cai, Le-Yi; Ding, Jian; Gao, Wei-Yang

2014-01-01

The aim of this study was to investigate the relationship between cell adhesion and anoikis evasion among human osteosarcoma cells (MG-63), and to further study the molecular mechanisms. Human osteosarcoma cells (MG-63) were assessed for apoptosis, and caspase-3, E-cadherin and β-catenin expression in EDTA and control non-EDTA groups. MG-63 cells were predominantly aggregated when in suspension, and the suspended cells were more dispersed in the EDTA group. Following culture in suspension for 24 h, 48 h, or 72 h, the rates of apoptosis were 34.88%±3.64%, 59.3%±7.22% and 78.5%±5.21% in the experimental group and 7.34%±2.13%, 14.7%±3.69%, and 21.4%±3.60% in the control group, respectively. Caspase-3 expression progressively increased and E-cadherin and β-catenin were decreased in the experimental group, whereas there was no change in the control group. MG-63 cells could avoid anoikis through cell adhesion, and E-cadherin might play a role in this process.

1α,25-Dihydroxyvitamin D(3) inhibits vascular cellular adhesion molecule-1 expression and interleukin-8 production in human coronary arterial endothelial cells.

Science.gov (United States)

Kudo, Keiko; Hasegawa, Shunji; Suzuki, Yasuo; Hirano, Reiji; Wakiguchi, Hiroyuki; Kittaka, Setsuaki; Ichiyama, Takashi

2012-11-01

Kawasaki disease is an acute febrile vasculitis of childhood that is associated with elevated production of inflammatory cytokines, causing damage to the coronary arteries. The production of proinflammatory cytokines and expression of adhesion molecules in human coronary arterial endothelial cells (HCAECs) is regulated by nuclear transcription factor-κB (NF-κB) activation. We have previously reported that the active form of vitamin D, 1α,25-dihydroxyvitamin D(3) (1α,25-(OH)(2)D(3)), inhibits tumor necrosis factor-α (TNF-α)-induced NF-κB activation. In this study, we examined the anti-inflammatory effects of 1α,25-(OH)(2)D(3) on TNF-α-induced adhesion molecule expression (vascular cellular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1)) and cytokine production (interleukin-6 (IL-6) and IL-8) in HCAECs. Pretreatment with 1α,25-(OH)(2)D(3) significantly inhibited TNF-α-induced VCAM-1 expression and IL-8 production in HCAECs. Our results suggest that adjunctive 1α,25-(OH)(2)D(3) therapy may modulate the inflammatory response during Kawasaki disease vasculitis. Copyright © 2012 Elsevier Ltd. All rights reserved.

Differential effect of L3T4+ cells on recovery from total-body irradiation

International Nuclear Information System (INIS)

Pantel, K.; Nakeff, A.

1990-01-01

We have examined the importance of L3T4+ (murine equivalent to CD4+) cells for hematopoietic regulation in vivo in unperturbed mice and mice recovering from total-body irradiation (TBI) using a cytotoxic monoclonal antibody (MoAb) raised with the GK 1.5 hybridoma. Ablating L3T4+ cells in normal (unperturbed) B6D2F1 mice substantially decreased the S-phase fraction (determined by in vivo hydroxyurea suicide) of erythroid progenitor cells (erythroid colony-forming units, CFU-E) as compared to the pretreatment level (10% +/- 14.1% [day 3 following depletion] vs 79.8% +/- 15.9%, respectively) with a corresponding decrease in the marrow content of CFU-E at this time to approximately 1% of the pretreatment value. Although the S-phase fraction of CFU-GM was decreased to 2.2% +/- 3.1% 3 days after L3T4+ cell ablation from the 21.3% +/- 8.3% pretreatment value, CFU-GM cellularity showed little change over the 3 days following anti-L3T4 treatment. Anti-L3T4 MoAb treatment had little or no effect on either the S-phase fraction or the marrow content of hematopoietic stem cells (spleen colony-forming units, CFU-S) committed to myeloerythroid differentiation. Ablating L3T4+ cells prior to a single dose of 2 Gy TBI resulted in significantly reduced marrow contents of CFU-S on day 3 and granulocyte-macrophage colony-forming units (CFU-GM) on day 6 following TBI, with little or no effect on the corresponding recovery of CFU-E. The present findings provide the first in vivo evidence that L3T4+ cells are involved in: (1) maintaining the proliferative activity of CFU-E and CFU-GM in unperturbed mice and (2) supporting the restoration of CFU-S and CFU-GM following TBI-induced myelosuppression

GPM GROUND VALIDATION NOAA UHF 449 PROFILER RAW DATA SPC FORMAT MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The NOAA UHF 449 Profiler Raw SPC foramt data was collected during the NASA supported Midlatitude Continental Convective Clouds Experiment (MC3E). The Ultra High...

GPM GROUND VALIDATION NOAA UHF 449 PROFILER RAW DATA SPC FORMAT MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation NOAA UHF 449 Profiler Raw Data SPC Format MC3E dataset was collected during the NASA supported Midlatitude Continental Convective Clouds...

Differential expression of fatty acid uptake in 3T3-L1 cells

International Nuclear Information System (INIS)

Waggoner, D.; Bernlohr, D.A.

1987-01-01

Cultured 3T3-L1 cells have been used as a model system to investigate the mechanism of fatty acid uptake by adipose tissue. Using a 1:1 molar ratio of 14 C-oleate and defatted bovine serum albumin (BSA), fatty acid (FA) uptake was quantitated at 4 0 and 37 0 as cell associated radioactivity. The profile of FA uptake in preadipocytes and adipocytes was biphasic; an initial rapid phase (1-20s) followed by a second slower phase (60-480s). At 37 0 the initial rate of FA accumulation in preadipocytes was identical to that in adipocytes, whereas the rate of accumulation during the second phase increased 7-fold (100 μM total FA) as a consequence of adipose conversion. When uptake measurements were made at 4 0 in adipocytes, the initial rate was identical to that at 37 0 , however the rate of second phase decreased 5-fold. Incubation of 14 C-BSA and nonradiolabeled FA with adipocyte monolayers (100 μM total FA) resulted in the rapid association (t/sub 1/2/ = 20s) of the BSA-FA complex with the cell surface. Incubation of 100, 10, and 1 μM total FA with adipocytes resulted in a 50-fold change in FA accumulation during the second phase. These results suggest that (1) FA uptake is significantly increased after differentiation, suggesting the participation of specialized proteins, (2) the temperature-insensitive initial FA accumulation can be attributed to rapid association of the BSA-FA complex to the cell surface, (3) the second phase of FA accumulation represents uptake

Drug-induced in vitro inhibition of neutrophil-endothelial cell adhesion.

Science.gov (United States)

Pellegatta, F.; Lu, Y.; Radaelli, A.; Zocchi, M. R.; Ferrero, E.; Chierchia, S.; Gaja, G.; Ferrero, M. E.

1996-01-01

1. Leukocyte-endothelial cell interactions play an important role during ischaemia-reperfusion events. Adhesion molecules are specifically implicated in this interaction process. 2. Since defibrotide has been shown to be an efficient drug in reducing damage due to ischaemia-reperfusion in many experimental models, we analysed the effect of defibrotide in vitro on leukocyte adhesion to endothelial cells in basal conditions and after their stimulation. 3. In basal conditions, defibrotide (1000 micrograms ml-1) partially inhibited leukocyte adhesion to endothelial cells by 17.3% +/- 3.6 (P defibrotide. 5. This result was confirmed in NIH/3T3-ICAM-1 transfected cells. 6. We conclude that defibrotide is able to interfere with leukocyte adhesion to endothelial cells mainly in activated conditions and that the ICAM-1/LFA-1 adhesion system is involved in the defibrotide mechanism of action. PMID:8762067

Cytotoxic Vibrio T3SS1 Rewires Host Gene Expression to Subvert Cell Death Signaling and Activate Cell Survival Networks

Science.gov (United States)

De Nisco, Nicole J.; Kanchwala, Mohammed; Li, Peng; Fernandez, Jessie; Xing, Chao; Orth, Kim

2017-01-01

Bacterial effectors are potent manipulators of host signaling pathways. The marine bacterium Vibrio parahaemolyticus (V. para), delivers effectors into host cells through two type three secretion systems (T3SS). The ubiquitous T3SS1 is vital for V. para survival in the environment, whereas T3SS2 causes acute gastroenteritis in human hosts. Although the natural host is undefined, T3SS1 effectors attack highly conserved cellular processes and pathways to orchestrate non-apoptotic cell death. Much is known about how T3SS1 effectors function in isolation, but we wanted to understand how their concerted action globally affects host cell signaling. To assess the host response to T3SS1, we compared gene expression changes over time in primary fibroblasts infected with V. para that have a functional T3SS1 (T3SS1+) to those in cells infected with V. para lacking T3SS1 (T3SS1−). Overall, the host transcriptional response to both T3SS1+ and T3SS1− V. para was rapid, robust, and temporally dynamic. T3SS1 re-wired host gene expression by specifically altering the expression of 398 genes. Although T3SS1 effectors target host cells at the posttranslational level to cause cytotoxicity, network analysis indicated that V. para T3SS1 also precipitates a host transcriptional response that initially activates cell survival and represses cell death networks. The increased expression of several key pro-survival transcripts mediated by T3SS1 was dependent on a host signaling pathway that is silenced later in infection by the posttranslational action of T3SS1. Taken together, our analysis reveals a complex interplay between roles of T3SS1 as both a transcriptional and posttranslational manipulator of host cell signaling. PMID:28512145

In vitro evaluation of poly(ethylene glycol)-block-poly(ε-caprolactone) methyl ether copolymer coating effects on cells adhesion and proliferation

Energy Technology Data Exchange (ETDEWEB)

Rusen, Laurentiu [National Institute for Lasers, Plasma and Radiation Physics, Bucharest (Romania); Neacsu, Patricia; Cimpean, Anisoara [University of Bucharest, Department of Biochemistry and Molecular Biology, Bucharest (Romania); Valentin, Ion; Brajnicov, Simona; Dumitrescu, L.N. [National Institute for Lasers, Plasma and Radiation Physics, Bucharest (Romania); Banita, Janina [University of Bucharest, Faculty of Chemistry, Bucharest (Romania); IBAR, Institute of Biochemistry of the Romanian Academy, 296 Splaiul Independentei, RO-060031 Bucharest (Romania); Dinca, Valentina, E-mail: valentina.dinca@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Bucharest (Romania); Dinescu, Maria [National Institute for Lasers, Plasma and Radiation Physics, Bucharest (Romania)

2016-06-30

Understanding and controlling natural and synthetic biointerfaces is known to be the key to a wide variety of application within cell culture and tissue engineering field. As both material characteristics and methods are important in tailoring biointerfaces characteristics, in this work we explore the feasibility of using Matrix Assisted Pulsed Laser Evaporation technique for obtaining synthetic copolymeric biocoatings (i.e. poly(ethylene glycol)-block-poly(ε-caprolactone) methyl ether) for evaluating in vitro Vero and MC3T3-E1 pre-osteoblasts cell response. Characterization and evaluation of the coated substrates were carried out using different techniques. The Fourier transform infrared spectroscopy data demonstrated that the main functional groups in the MAPLE-deposited films remained intact. Atomic Force Microscopy images showed the coatings to be continuous, with the surface roughness depending on the deposition parameters. Moreover, the behaviour of the coatings in medium mimicking the pH and temperature of the human body was studied and corelated to degradation. Spectro-ellipsometry (SE) and AFM measurements revealed the degradation trend during immersion time by the changes in coating thickness and roughness. In vitro biocompatibility was studied by indirect contact tests on Vero cells in accordance with ISO 10993-5/2009. The results obtained in terms of cell morphology (phase contrast microscopy) and cytotoxicity (LDH and MTT assays) proved biocompatibility. Furthermore, direct contact assays on MC3T3-E1 pre-osteoblasts demonstrated the capacity of all analyzed specimens to support cell adhesion, normal cellular morphology and growth.

In vitro evaluation of poly(ethylene glycol)-block-poly(ɛ-caprolactone) methyl ether copolymer coating effects on cells adhesion and proliferation

Science.gov (United States)

Rusen, Laurentiu; Neacsu, Patricia; Cimpean, Anisoara; Valentin, Ion; Brajnicov, Simona; Dumitrescu, L. N.; Banita, Janina; Dinca, Valentina; Dinescu, Maria

2016-06-01

Understanding and controlling natural and synthetic biointerfaces is known to be the key to a wide variety of application within cell culture and tissue engineering field. As both material characteristics and methods are important in tailoring biointerfaces characteristics, in this work we explore the feasibility of using Matrix Assisted Pulsed Laser Evaporation technique for obtaining synthetic copolymeric biocoatings (i.e. poly(ethylene glycol)-block-poly(ɛ-caprolactone) methyl ether) for evaluating in vitro Vero and MC3T3-E1 pre-osteoblasts cell response. Characterization and evaluation of the coated substrates were carried out using different techniques. The Fourier transform infrared spectroscopy data demonstrated that the main functional groups in the MAPLE-deposited films remained intact. Atomic Force Microscopy images showed the coatings to be continuous, with the surface roughness depending on the deposition parameters. Moreover, the behaviour of the coatings in medium mimicking the pH and temperature of the human body was studied and corelated to degradation. Spectro-ellipsometry (SE) and AFM measurements revealed the degradation trend during immersion time by the changes in coating thickness and roughness. In vitro biocompatibility was studied by indirect contact tests on Vero cells in accordance with ISO 10993-5/2009. The results obtained in terms of cell morphology (phase contrast microscopy) and cytotoxicity (LDH and MTT assays) proved biocompatibility. Furthermore, direct contact assays on MC3T3-E1 pre-osteoblasts demonstrated the capacity of all analyzed specimens to support cell adhesion, normal cellular morphology and growth.

Notch3 is dispensable for thymocyte β-selection and Notch1-induced T cell leukemogenesis.

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Sara Suliman

Full Text Available Notch1 (N1 signaling induced by intrathymic Delta-like (DL ligands is required for T cell lineage commitment as well as self-renewal during "β-selection" of TCRβ⁺CD4⁻CD8⁻ double negative 3 (DN3 T cell progenitors. However, over-expression of the N1 intracellular domain (ICN1 renders N1 activation ligand-independent and drives leukemic transformation during β-selection. DN3 progenitors also express Notch3 (N3 mRNA, and over-expression of ligand-independent mutant N3 (ICN3 influences β-selection and drives T cell leukemogenesis. However, the importance of ligand-activated N3 in promoting β-selection and ICN1-induced T cell leukemogenesis has not been examined. To address these questions we generated mice lacking functional N3. We confirmed that DN3 progenitors express N3 protein using a N3-specific antibody. Surprisingly however, N3-deficient DN3 thymocytes were not defective in generating DP thymocytes under steady state conditions or in more stringent competition assays. To determine if N3 co-operates with N1 to regulate β-selection, we generated N1;N3 compound mutants. However, N3 deficiency did not exacerbate the competitive defect of N1⁺/⁻ DN3 progenitors, demonstrating that N3 does not compensate for limiting N1 during T cell development. Finally, N3 deficiency did not attenuate T cell leukemogenesis induced by conditional expression of ICN1 in DN3 thymocytes. Importantly, we showed that in contrast to N1, N3 has a low binding affinity for DL4, the most abundant intrathymic DL ligand. Thus, despite the profound effects of ectopic ligand-independent N3 activation on T cell development and leukemogenesis, physiologically activated N3 is dispensable for both processes, likely because N3 interacts poorly with intrathymic DL4.

Design and Characterization of a Sensorized Microfluidic Cell-Culture System with Electro-Thermal Micro-Pumps and Sensors for Cell Adhesion, Oxygen, and pH on a Glass Chip

Directory of Open Access Journals (Sweden)

Sebastian M. Bonk

2015-07-01

Full Text Available We combined a multi-sensor glass-chip with a microfluidic channel grid for the characterization of cellular behavior. The grid was imprinted in poly-dimethyl-siloxane. Mouse-embryonal/fetal calvaria fibroblasts (MC3T3-E1 were used as a model system. Thin-film platinum (Pt sensors for respiration (amperometric oxygen electrode, acidification (potentiometric pH electrodes and cell adhesion (interdigitated-electrodes structures, IDES allowed us to monitor cell-physiological parameters as well as the cell-spreading behavior. Two on-chip electro-thermal micro-pumps (ETμPs permitted the induction of medium flow in the system, e.g., for medium mixing and drug delivery. The glass-wafer technology ensured the microscopic observability of the on-chip cell culture. Connecting Pt structures were passivated by a 1.2 μm layer of silicon nitride (Si3N4. Thin Si3N4 layers (20 nm or 60 nm were used as the sensitive material of the pH electrodes. These electrodes showed a linear behavior in the pH range from 4 to 9, with a sensitivity of up to 39 mV per pH step. The oxygen sensors were circular Pt electrodes with a sensor area of 78.5 μm2. Their sensitivity was 100 pA per 1% oxygen increase in the range from 0% to 21% oxygen (air saturated. Two different IDES geometries with 30- and 50-μm finger spacings showed comparable sensitivities in detecting the proliferation rate of MC3T3 cells. These cells were cultured for 11 days in vitro to test the biocompatibility, microfluidics and electric sensors of our system under standard laboratory conditions.

Isolation and characterization of NIH 3T3 cells expressing polyomavirus small T antigen

International Nuclear Information System (INIS)

Noda, T.; Satake, M.; Robins, T.; Ito, Y.

1986-01-01

The polyomavirus small T-antigen gene, together with the polyomavirus promoter, was inserted into retrovirus vector pGV16 which contains the Moloney sarcoma virus long terminal repeat and neomycin resistance gene driven by the simian virus 40 promoter. This expression vector, pGVST, was packaged into retrovirus particles by transfection of PSI2 cells which harbor packaging-defective murine retrovirus genome. NIH 3T3 cells were infected by this replication-defective retrovirus containing pGVST. Of the 15 G418-resistant cell clones, 8 express small T antigen at various levels as revealed by immunoprecipitation. A cellular protein with an apparent molecular weight of about 32,000 coprecipitates with small T antigen. Immunofluorescent staining shows that small T antigen is mainly present in the nuclei. Morphologically, cells expressing small T antigen are indistinguishable from parental NIH 3T3 cells and have a microfilament pattern similar to that in parental NIH 3T3 cells. Cells expressing small T antigen form a flat monolayer but continue to grow beyond the saturation density observed for parental NIH 3T3 cells and eventually come off the culture plate as a result of overconfluency. There is some correlation between the level of expression of small T antigen and the growth rate of the cells. Small T-antigen-expressing cells form small colonies in soft agar. However, the proportion of cells which form these small colonies is rather small. A clone of these cells tested did not form tumors in nude mice within 3 months after inoculation of 10 6 cells per animal. Thus, present studies establish that the small T antigen of polyomavirus is a second nucleus-localized transforming gene product of the virus (the first one being large T antigen) and by itself has a function which is to stimulate the growth of NIH 3T3 cells beyond their saturation density in monolayer culture

In vitro study of 3D PLGA/n-HAp/β-TCP composite scaffolds with etched oxygen plasma surface modification in bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Roh, Hee-Sang [Department of Dental Materials, School of Dentistry, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452 (Korea, Republic of); Jung, Sang-Chul [Department of Environmental Engineering, Sunchon National University, 255 Jungang-ro, Sunchon 57922 (Korea, Republic of); Kook, Min-Suk [Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186 (Korea, Republic of); Kim, Byung-Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452 (Korea, Republic of)

2016-12-01

Highlights: • PLGA and PLGA/n-HAp/β-TCP scaffolds were successfully fabricated by 3D printing. • Oxygen plasma etching increases the wettability and surface roughness. • Bioceramics and oxygen plasma etching and could be used to improve the cell affinity. - Abstract: Three-dimensional (3D) scaffolds have many advantageous properties for bone tissue engineering application, due to its controllable properties such as pore size, structural shape and interconnectivity. In this study, effects on oxygen plasma surface modification and adding of nano-hydroxyapatite (n-HAp) and β-tricalcium phosphate (β-TCP) on the 3D PLGA/n-HAp/β-TCP scaffolds for improving preosteoblast cell (MC3T3-E1) adhesion, proliferation and differentiation were investigated. The 3D PLGA/n-HAp/β-TCP scaffolds were fabricated by 3D Bio-Extruder equipment. The 3D scaffolds were prepared with 0°/90° architecture and pore size of approximately 300 μm. In addition 3D scaffolds surface were etched by oxygen plasma to enhance the hydrophilic property and surface roughness. After oxygen plasma treatment, the surface chemistry and morphology were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. And also hydrophilic property was measured by contact angle. The MC3T3-E1 cell proliferation and differentiation were investigated by MTT assay and ALP activity. In present work, the 3D PLGA/HAp/beta-TCP composite scaffold with suitable structure for the growth of osteoblast cells was successfully fabricated by 3D rapid prototyping technique. The surface hydrophilicity and roughness of 3D scaffold increased by oxygen plasma treatment had a positive effect on cell adhesion, proliferation, and differentiation. Furthermore, the differentiation of MC3T3-E1 cell was significantly enhanced by adding of n-HAp and β-TCP on 3D PLGA scaffold. As a result, combination of bioceramics and oxygen plasma treatment showed a synergistic effect on

Inhibition of STAT3 phosphorylation by sulforaphane reduces adhesion molecule expression in vascular endothelial cell.

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Cho, Young S; Kim, Chan H; Ha, Tae S; Ahn, Hee Y

2015-11-18

Intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) play key roles in the initiation of vascular inflammation. In this study, we explored whether sulforaphane, a dietary phytochemical, can inhibit the expression of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS), and the mechanisms involved. Sulforaphane prevented the LPS-mediated increase in ICAM-1 and VCAM-1 expression, (P < 0.01) in HUVEC. Sulforaphane also prevented the LPS-mediated increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) (P < 0.01). Stattic, a STAT3 inhibitor, reduced the LPS-induced expression of ICAM-1 and VCAM-1, and STAT3 phosphorylation (P < 0.01). STAT3 small interfering RNA treatment reduced the LPS-induced expression of ICAM-1, VCAM-1, and STAT3 (P < 0.01). Sulforaphane reduced LPS-mediated THP-1 monocyte adhesion to HUVEC (P < 0.01). In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, and this effect was prevented by sulforaphane. These data provide insight into the mechanism through which sulforaphane partly reduces the expression of ICAM-1 and VCAM-1 on the vascular wall by inhibiting STAT3 phosphorylation.

Local 3D matrix microenvironment regulates cell migration through spatiotemporal dynamics of contractility-dependent adhesions

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Doyle, Andrew D.; Carvajal, Nicole; Jin, Albert; Matsumoto, Kazue; Yamada, Kenneth M.

2015-11-01

The physical properties of two-dimensional (2D) extracellular matrices (ECMs) modulate cell adhesion dynamics and motility, but little is known about the roles of local microenvironmental differences in three-dimensional (3D) ECMs. Here we generate 3D collagen gels of varying matrix microarchitectures to characterize their regulation of 3D adhesion dynamics and cell migration. ECMs containing bundled fibrils demonstrate enhanced local adhesion-scale stiffness and increased adhesion stability through balanced ECM/adhesion coupling, whereas highly pliable reticular matrices promote adhesion retraction. 3D adhesion dynamics are locally regulated by ECM rigidity together with integrin/ECM association and myosin II contractility. Unlike 2D migration, abrogating contractility stalls 3D migration regardless of ECM pore size. We find force is not required for clustering of activated integrins on 3D native collagen fibrils. We propose that efficient 3D migration requires local balancing of contractility with ECM stiffness to stabilize adhesions, which facilitates the detachment of activated integrins from ECM fibrils.

Heterologous expression of C. elegans fat-1 decreases the n-6/n-3 fatty acid ratio and inhibits adipogenesis in 3T3-L1 cells

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An, Lei; Pang, Yun-Wei; Gao, Hong-Mei; Tao, Li; Miao, Kai; Wu, Zhong-Hong

2012-01-01

Highlights: ► Expression of C. elegans fat-1 reduces the n-6/n-3 PUFA ratio in 3T3-L1 cells. ► fat-1 inhibits the proliferation and differentiation of 3T3-L1 preadipocytes. ► fat-1 reduces lipid deposition in 3T3-L1 adipocytes. ► The lower n-6/n-3 ratio induces apoptosis in 3T3-L1 adipocytes. -- Abstract: In general, a diet enriched in polyunsaturated fatty acids (PUFAs) inhibits the development of obesity and decreases adipose tissue. The specific impacts of n-3 and n-6 PUFAs on adipogenesis, however, have not been definitively determined. Traditional in vivo and in vitro supplementation studies have yielded inconsistent or even contradictory results, which likely reflect insufficiently controlled experimental systems. Caenorhabditiselegans fat-1 gene encodes an n-3 fatty acid desaturase, and its heterologous expression represents an effective method both for altering the n-6/n-3 PUFA ratio and for evaluating the biological effects of n-3 and n-6 PUFAs. We sought to determine whether a reduced n-6/n-3 ratio could influence adipogenesis in 3T3-L1 cells. Lentivirus-mediated introduction of the fat-1 gene into 3T3-L1 preadipocytes significantly reduced the n-6/n-3 ratio and inhibited preadipocyte proliferation and differentiation. In mature adipocytes, fat-1 expression reduced lipid deposition, as measured by Oil Red O staining, and induced apoptosis. Our results indicate that a reduced n-6/n-3 ratio inhibits adipogenesis through several mechanisms and that n-3 PUFAs more effectively inhibit adipogenesis (but not lipogenesis) than do n-6 PUFAs.

Effect of copper-doped silicate 13–93 bioactive glass scaffolds on the response of MC3T3-E1 cells in vitro and on bone regeneration and angiogenesis in rat calvarial defects in vivo

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Lin, Yinan; Xiao, Wei [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Bal, B. Sonny [Department of Orthopaedic Surgery, University of Missouri, Columbia, MO 65212 (United States); Rahaman, Mohamed N., E-mail: rahaman@mst.edu [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States)

2016-10-01

The release of inorganic ions from biomaterials could provide an alternative approach to the use of growth factors for improving tissue healing. In the present study, the release of copper (Cu) ions from bioactive silicate (13–93) glass scaffolds on the response of cells in vitro and on bone regeneration and angiogenesis in vivo was studied. Scaffolds doped with varying concentrations of Cu (0–2.0 wt.% CuO) were created with a grid-like microstructure by robotic deposition. When immersed in simulated body fluid in vitro, the Cu-doped scaffolds released Cu ions into the medium in a dose-dependent manner and converted partially to hydroxyapatite. The proliferation and alkaline phosphatase activity of pre-osteoblastic MC3T3-E1 cells cultured on the scaffolds were not affected by 0.4 and 0.8 wt.% CuO in the glass but they were significantly reduced by 2.0 wt.% CuO. The percent new bone that infiltrated the scaffolds implanted for 6 weeks in rat calvarial defects (46 ± 8%) was not significantly affected by 0.4 or 0.8 wt.% CuO in the glass whereas it was significantly inhibited (0.8 ± 0.7%) in the scaffolds doped with 2.0 wt.% CuO. The area of new blood vessels in the fibrous tissue that infiltrated the scaffolds increased with CuO content of the glass and was significantly higher for the scaffolds doped with 2.0 wt.% CuO. Loading the scaffolds with bone morphogenetic protein-2 (1 μg/defect) significantly enhanced bone infiltration and reduced fibrous tissue in the scaffolds. These results showed that doping the 13–93 glass scaffolds with up to 0.8 wt.% CuO did not affect their biocompatibility whereas 2.0 wt.% CuO was toxic to cells and detrimental to bone regeneration. - Highlights: • First study to evaluate Cu ion release from silicate (13-93) bioactive glass scaffolds on osteogenesis in vivo • Released Cu ions influenced bone regeneration in a dose dependent manner • Lower concentrations of Cu ions had little effect on bone regeneration • Cu ion

Effect of copper-doped silicate 13–93 bioactive glass scaffolds on the response of MC3T3-E1 cells in vitro and on bone regeneration and angiogenesis in rat calvarial defects in vivo

International Nuclear Information System (INIS)

Lin, Yinan; Xiao, Wei; Bal, B. Sonny; Rahaman, Mohamed N.

2016-01-01

The release of inorganic ions from biomaterials could provide an alternative approach to the use of growth factors for improving tissue healing. In the present study, the release of copper (Cu) ions from bioactive silicate (13–93) glass scaffolds on the response of cells in vitro and on bone regeneration and angiogenesis in vivo was studied. Scaffolds doped with varying concentrations of Cu (0–2.0 wt.% CuO) were created with a grid-like microstructure by robotic deposition. When immersed in simulated body fluid in vitro, the Cu-doped scaffolds released Cu ions into the medium in a dose-dependent manner and converted partially to hydroxyapatite. The proliferation and alkaline phosphatase activity of pre-osteoblastic MC3T3-E1 cells cultured on the scaffolds were not affected by 0.4 and 0.8 wt.% CuO in the glass but they were significantly reduced by 2.0 wt.% CuO. The percent new bone that infiltrated the scaffolds implanted for 6 weeks in rat calvarial defects (46 ± 8%) was not significantly affected by 0.4 or 0.8 wt.% CuO in the glass whereas it was significantly inhibited (0.8 ± 0.7%) in the scaffolds doped with 2.0 wt.% CuO. The area of new blood vessels in the fibrous tissue that infiltrated the scaffolds increased with CuO content of the glass and was significantly higher for the scaffolds doped with 2.0 wt.% CuO. Loading the scaffolds with bone morphogenetic protein-2 (1 μg/defect) significantly enhanced bone infiltration and reduced fibrous tissue in the scaffolds. These results showed that doping the 13–93 glass scaffolds with up to 0.8 wt.% CuO did not affect their biocompatibility whereas 2.0 wt.% CuO was toxic to cells and detrimental to bone regeneration. - Highlights: • First study to evaluate Cu ion release from silicate (13-93) bioactive glass scaffolds on osteogenesis in vivo • Released Cu ions influenced bone regeneration in a dose dependent manner • Lower concentrations of Cu ions had little effect on bone regeneration • Cu ion

T1R3 homomeric sweet taste receptor regulates adipogenesis through Gαs-mediated microtubules disassembly and Rho activation in 3T3-L1 cells.

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Yosuke Masubuchi

Full Text Available We previously reported that 3T3-L1 cells express a functional sweet taste receptor possibly as a T1R3 homomer that is coupled to Gs and negatively regulates adipogenesis by a Gαs-mediated but cAMP-independent mechanism. Here, we show that stimulation of this receptor with sucralose or saccharin induced disassembly of the microtubules in 3T3-L1 preadipocytes, which was attenuated by overexpression of the dominant-negative mutant of Gαs (Gαs-G226A. In contrast, overexpression of the constitutively active mutant of Gαs (Gαs-Q227L as well as treatment with cholera toxin or isoproterenol but not with forskolin caused disassembly of the microtubules. Sweetener-induced microtubule disassembly was accompanied by activation of RhoA and Rho-associated kinase (ROCK. This was attenuated with by knockdown of GEF-H1, a microtubule-localized guanine nucleotide exchange factor for Rho GTPase. Furthermore, overexpression of the dominant-negative mutant of RhoA (RhoA-T19N blocked sweetener-induced dephosphorylation of Akt and repression of PPARγ and C/EBPα in the early phase of adipogenic differentiation. These results suggest that the T1R3 homomeric sweet taste receptor negatively regulates adipogenesis through Gαs-mediated microtubule disassembly and consequent activation of the Rho/ROCK pathway.

Cell-Adhesive Bioinspired and Catechol-Based Multilayer Freestanding Membranes for Bone Tissue Engineering

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Maria P. Sousa

2017-10-01

Full Text Available Mussels are marine organisms that have been mimicked due to their exceptional adhesive properties to all kind of surfaces, including rocks, under wet conditions. The proteins present on the mussel’s foot contain 3,4-dihydroxy-l-alanine (DOPA, an amino acid from the catechol family that has been reported by their adhesive character. Therefore, we synthesized a mussel-inspired conjugated polymer, modifying the backbone of hyaluronic acid with dopamine by carbodiimide chemistry. Ultraviolet–visible (UV–Vis spectroscopy and nuclear magnetic resonance (NMR techniques confirmed the success of this modification. Different techniques have been reported to produce two-dimensional (2D or three-dimensional (3D systems capable to support cells and tissue regeneration; among others, multilayer systems allow the construction of hierarchical structures from nano- to macroscales. In this study, the layer-by-layer (LbL technique was used to produce freestanding multilayer membranes made uniquely of chitosan and dopamine-modified hyaluronic acid (HA-DN. The electrostatic interactions were found to be the main forces involved in the film construction. The surface morphology, chemistry, and mechanical properties of the freestanding membranes were characterized, confirming the enhancement of the adhesive properties in the presence of HA-DN. The MC3T3-E1 cell line was cultured on the surface of the membranes, demonstrating the potential of these freestanding multilayer systems to be used for bone tissue engineering.

Synergy between type 1 fimbriae expression and C3 opsonisation increases internalisation of E. coli by human tubular epithelial cells.

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Li, Ke; Zhou, Wuding; Hong, Yuzhi; Sacks, Steven H; Sheerin, Neil S

2009-03-31

Bacterial infection of the urinary tract is a common clinical problem with E. coli being the most common urinary pathogen. Bacterial uptake into epithelial cells is increasingly recognised as an important feature of infection. Bacterial virulence factors, especially fimbrial adhesins, have been conclusively shown to promote host cell invasion. Our recent study reported that C3 opsonisation markedly increases the ability of E. coli strain J96 to internalise into human proximal tubular epithelial cells via CD46, a complement regulatory protein expressed on host cell membrane. In this study, we further assessed whether C3-dependent internalisation by human tubular epithelial cells is a general feature of uropathogenic E. coli and investigated features of the bacterial phenotype that may account for any heterogeneity. In 31 clinical isolates of E. coli tested, C3-dependent internalisation was evident in 10 isolates. Type 1 fimbriae mediated-binding is essential for C3-dependent internalisation as shown by phenotypic association, type 1 fimbrial blockade with soluble ligand (mannose) and by assessment of a type 1 fimbrial mutant. we propose that efficient internalisation of uropathogenic E. coli by the human urinary tract depends on co-operation between type 1 fimbriae-mediated adhesion and C3 receptor -ligand interaction.

Non-enzymatic glycosylation of a type I collagen matrix: effects on osteoblastic development and oxidative stress

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Barrio Daniel A

2001-08-01

Full Text Available Abstract Background The tissue accumulation of protein-bound advanced glycation endproducts (AGE may be involved in the etiology of diabetic chronic complications, including osteopenia. The aim of this study was to investigate the effect of an AGE-modified type I collagen substratum on the adhesion, spreading, proliferation and differentiation of rat osteosarcoma UMR106 and mouse non-transformed MC3T3E1 osteoblastic cells. We also studied the role of reactive oxygen species (ROS and nitric oxide synthase (NOS expression on these AGE-collagen mediated effects. Results AGE-collagen decreased the adhesion of UMR106 cells, but had no effect on the attachment of MC3T3E1 cells. In the UMR106 cell line, AGE-collagen also inhibited cellular proliferation, spreading and alkaline phosphatase (ALP activity. In preosteoblastic MC3T3E1 cells (24-hour culture, proliferation and spreading were significantly increased by AGE-collagen. After one week of culture (differentiated MC3T3E1 osteoblasts AGE-collagen inhibited ALP activity, but had no effect on cell number. In mineralizing MC3T3E1 cells (3-week culture AGE-collagen induced a decrease in the number of surviving cells and of extracellular nodules of mineralization, without modifying their ALP activity. Intracellular ROS production, measured after a 48-hour culture, was decreased by AGE-collagen in MC3T3E1 cells, but was increased by AGE-collagen in UMR106 cells. After a 24-hour culture, AGE-collagen increased the expression of endothelial and inducible NOS, in both osteoblastic cell lines. Conclusions These results suggest that the accumulation of AGE on bone extracellular matrix could regulate the proliferation and differentiation of osteoblastic cells. These effects appear to depend on the stage of osteoblastic development, and possibly involve the modulation of NOS expression and intracellular ROS pathways.

Effects of CD44 and E-cadherin overexpression on the proliferation, adhesion and invasion of ovarian cancer cells.

Science.gov (United States)

Mao, Meiya; Zheng, Xiaojiao; Jin, Bohong; Zhang, Fubin; Zhu, Linyan; Cui, Lining

2017-12-01

CD44 is a prognostic indicator of shorter survival time in ovarian cancer. E-cadherin fragmentation promotes the progression of ovarian cancer. However, the effects of CD44 and E-cadherin overexpression on ovarian cancer cells have remained elusive. The present study aimed to investigate the effects of overexpression of CD44 and E-cadherin on cell proliferation, adhesion and invasion of SKOV-3 and OVCAR-3 ovarian cancer cells. Overexpression of CD44 and E-cadherin was achieved by transfecting SKOV-3 and OVCAR-3 cells with viruses carrying the CD44 or E-cadherin gene, respectively. Expression of CD44 and E-cadherin was detected by western blot analysis. The proliferation of SKOV-3 and OVCAR-3 cells was measured by a Cell Counting Kit-8 at 0, 24 and 48 h after viral transfection. The adhesion ability of SKOV-3 and OVCAR-3 cells to the endothelial layer was detected. A Transwell invasion assay was utilized to assess the invasion ability of the cells. Overexpression of CD44 and E-cadherin in SKOV-3 and OVCAR-3 cells was confirmed by western blot. Compared with the blank or negative control groups, the CD44 overexpression groups of SKOV-3 and OVCAR-3 cells exhibited an increased cell proliferation rate at 24 and 48 h, whereas overexpression of E-cadherin did not alter the proliferation of these cells. Furthermore, compared with the blank and negative control groups, the cell adhesion and invasion ability in the CD44 overexpression groups of SKOV-3 and OVCAR-3 cells was markedly higher. There were no significant differences in adhesion ability between the E-cadherin overexpression group and the blank/negative control group. Of note, overexpression of E-cadherin decreased the invasive ability of SKOV-3 and OVCAR-3 cells. In conclusion, Overexpression of CD44 increased the proliferation, adhesion and invasion of ovarian cancer cells, while overexpression of E-cadherin decreased the invasion of ovarian cancer cells.

Survival advantages conferred to colon cancer cells by E-selectin-induced activation of the PI3K-NFκB survival axis downstream of Death receptor-3

International Nuclear Information System (INIS)

Porquet, Nicolas; Huot, Jacques; Poirier, Andrée; Houle, François; Pin, Anne-Laure; Gout, Stéphanie; Tremblay, Pierre-Luc; Paquet, Éric R; Klinck, Roscoe; Auger, François A

2011-01-01

Extravasation of circulating cancer cells is a key event of metastatic dissemination that is initiated by the adhesion of cancer cells to endothelial cells. It requires interactions between adhesion receptors on endothelial cells and their counter-receptors on cancer cells. Notably, E-selectin, a major endothelial adhesion receptor, interacts with Death receptor-3 present on metastatic colon carcinoma cells. This interaction confers metastatic properties to colon cancer cells by promoting the adhesion of cancer cells to endothelial cells and triggering the activation of the pro-migratory p38 and pro-survival ERK pathways in the cancer cells. In the present study, we investigated further the mechanisms by which the E-selectin-activated pathways downstream of DR3 confer a survival advantage to colon cancer cells. Cell survival has been ascertained by using the WST-1 assay and by evaluating the activation of the PI3 kinase/NFκB survival axis. Apoptosis has been assayed by determining DNA fragmentation by Hoechst staining and by measuring cleavage of caspases-8 and -3. DR3 isoforms have been identified by PCR. For more precise quantification, targeted PCR reactions were carried out, and the amplified products were analyzed by automated chip-based microcapillary electrophoresis on an Agilent 2100 Bioanalyzer instrument. Interaction between DR3-expressing HT29 colon carcinoma cells and E-selectin induces the activation of the PI3K/Akt pathway. Moreover, p65/RelA, the anti-apoptotic subunit of NFκB, is rapidly translocated to the nucleus in response to E-selectin. This translocation is impaired by the PI3K inhibitor LY294002. Furthermore, inhibition of the PI3K/Akt pathway increases the cleavage of caspase 8 in colon cancer cells treated with E-selectin and this effect is still further increased when both ERK and PI3K pathways are concomitantly inhibited. Intriguingly, metastatic colon cancer cell lines such as HT29 and SW620 express higher levels of a splice variant of

Survival advantages conferred to colon cancer cells by E-selectin-induced activation of the PI3K-NFκB survival axis downstream of Death receptor-3

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Paquet Éric R

2011-07-01

Full Text Available Abstract Background Extravasation of circulating cancer cells is a key event of metastatic dissemination that is initiated by the adhesion of cancer cells to endothelial cells. It requires interactions between adhesion receptors on endothelial cells and their counter-receptors on cancer cells. Notably, E-selectin, a major endothelial adhesion receptor, interacts with Death receptor-3 present on metastatic colon carcinoma cells. This interaction confers metastatic properties to colon cancer cells by promoting the adhesion of cancer cells to endothelial cells and triggering the activation of the pro-migratory p38 and pro-survival ERK pathways in the cancer cells. In the present study, we investigated further the mechanisms by which the E-selectin-activated pathways downstream of DR3 confer a survival advantage to colon cancer cells. Methods Cell survival has been ascertained by using the WST-1 assay and by evaluating the activation of the PI3 kinase/NFκB survival axis. Apoptosis has been assayed by determining DNA fragmentation by Hoechst staining and by measuring cleavage of caspases-8 and -3. DR3 isoforms have been identified by PCR. For more precise quantification, targeted PCR reactions were carried out, and the amplified products were analyzed by automated chip-based microcapillary electrophoresis on an Agilent 2100 Bioanalyzer instrument. Results Interaction between DR3-expressing HT29 colon carcinoma cells and E-selectin induces the activation of the PI3K/Akt pathway. Moreover, p65/RelA, the anti-apoptotic subunit of NFκB, is rapidly translocated to the nucleus in response to E-selectin. This translocation is impaired by the PI3K inhibitor LY294002. Furthermore, inhibition of the PI3K/Akt pathway increases the cleavage of caspase 8 in colon cancer cells treated with E-selectin and this effect is still further increased when both ERK and PI3K pathways are concomitantly inhibited. Intriguingly, metastatic colon cancer cell lines such as HT

Neuropilin 1 deficiency on CD4+Foxp3+ regulatory T cells impairs mouse melanoma growth