Integrating qPLM and Biomechanical Test Data With an Anisotropic Fiber Distribution Model and In Vitro Regulation of Articular Cartilage Fiber Modulus

2013 ◽  
Author(s):  
Michael E. Stender ◽  
Christopher B. Raub ◽  
Kevin A. Yamauchi ◽  
Reza Shirazi ◽  
Pasquale Vena ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Articular Cartilage ◽  
Growth Factor ◽  
Volume Fraction ◽  
Distribution Model ◽  
Fiber Distribution ◽  
Poisson's Ratios ◽  
Poisson’S Ratios ◽  
Tgf Β1

Articular cartilage (AC) metabolism and mechanical properties are regulated by in vitro culture with transforming growth factor–beta 1 (TGF-β1) and insulin-like growth factor–1 (IGF-1) [1]. In general, TGF-β1 maintains tissue size accompanied by a maintenance or increase in tensile and compressive moduli and a maintenance or decrease of compressive Poisson’s ratios while IGF-1 produces significant tissue expansion at the expense of reduced tensile and compressive moduli and increased compressive Poisson’s ratios [1,2]. The goal of this study was to integrate experimental data including AC mechanical properties, biochemical contents including overall collagen (COL) volume fraction, and micro structural measures of COL fiber distribution with a continuum mixture model to predict how COL fiber modulus changes in vitro with TGF-β1 and IGF-1 treatment.

scholarly journals In vitro Articular Cartilage Growth with Sequential Application of IGF-1 and TGF-β1 Enhances Volumetric Growth and Maintains Compressive Properties

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Nathan T. Balcom ◽  
Britta Berg-Johansen ◽  
Kristin J. Dills ◽  
Jennifer R. Van Donk ◽  
Gregory M. Williams ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Articular Cartilage ◽  
Growth Factor ◽  
Extreme Values ◽  
Volumetric Growth ◽  
Bovine Articular Cartilage ◽  
Poisson's Ratios ◽  
Poisson’S Ratios ◽  
Tgf Β1

In vitro cultures with insulin-like growth factor-1 (IGF-1) and transforming growth factor-β1 (TGF-β1) have previously been shown to differentially modulate the growth of immature bovine articular cartilage. IGF-1 stimulates expansive growth yet decreases compressive moduli and increases compressive Poisson’s ratios, whereas TGF-β1 maintains tissue size, increases compressive moduli, and decreases compressive Poisson’s ratios. The current study’s hypothesis was that sequential application of IGF-1 and TGF-β1 during in vitro culture produces geometric and compressive mechanical properties that lie between extreme values produced when using either growth factor alone. Immature bovine articular cartilage specimens were harvested and either untreated (D0, i.e., day zero) or cultured in vitro for either 6 days with IGF-1 (D6 IGF), 12 days with IGF-1 (D12 IGF), or 6 days with IGF-1 followed by 6 days with TGF-β1 (D12 SEQ, i.e., sequential). Following treatment, all specimens were tested for geometric, biochemical, and compressive mechanical properties. Relative to D0, D12 SEQ treatment enhanced volumetric growth, but to a lower value than that for D12 IGF. Furthermore, D12 SEQ treatment maintained compressive moduli and Poisson’s ratios at values higher and lower, respectively, than those for D12 IGF. Considering the previously described effects of 12 days of treatment with TGF-β1 alone, D12 SEQ induced both growth and mechanical property changes between those produced with either IGF-1 or TGF-β1 alone. The results suggest that it may be possible to vary the durations of select growth factors, including IGF-1 and TGF-β1, to more precisely modulate the geometric, biochemical, and mechanical properties of immature cartilage graft tissue in clinical repair strategies.

scholarly journals Differential regulation of immature articular cartilage compressive moduli and Poisson’s ratios by in vitro stimulation with IGF-1 and TGF-β1

2010 ◽  
Vol 43 (13) ◽  
pp. 2501-2507 ◽  
Author(s):  
Gregory M. Williams ◽  
Kristin J. Dills ◽  
Christian R. Flores ◽  
Michael E. Stender ◽  
Kevin M. Stewart ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Differential Regulation ◽  
Poisson's Ratios ◽  
Poisson’S Ratios ◽  
Tgf Β1

Combined Effects of Bone Marrow-Derived Mesenchymal Stem Cells and PLGA-PEG-PLGA Scaffolds on Repair of Articular Cartilage Defect

2013 ◽  
Vol 815 ◽  
pp. 345-349 ◽  
Author(s):  
Ching Wen Hsu ◽  
Ping Liu ◽  
Song Song Zhu ◽  
Feng Deng ◽  
Bi Zhang
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Articular Cartilage ◽  
Growth Factor ◽  
Cartilage Defect ◽  
Cartilage Regeneration ◽  
Tissue Growth ◽  
Cartilage Defects

Here we reported a combined technique for articular cartilage repair, consisting of bone arrow mesenchymal stem cells (BMMSCs) and poly (dl-lactide-co-glycolide-b-ethylene glycol-b-dl-lactide-co-glycolide) (PLGA-PEG-PLGA) triblock copolymers carried with tissue growth factor (TGF-belat1). In the present study, BMMSCs seeded on PLGA-PEG-PLGA with were incubated in vitro, carried or not TGF-belta1, Then the effects of the composite on repair of cartilage defect were evaluated in rabbit knee joints in vivo. Full-thickness cartilage defects (diameter: 5 mm; depth: 3 mm) in the patellar groove were either left empty (n=18), implanted with BMMSCs/PLGA (n=18), TGF-belta1 modified BMMSCs/PLGA-PEG-PLGA. The defect area was examined grossly, histologically at 6, 24 weeks postoperatively. After implantation, the BMMSCs /PLGA-PEG-PLGA with TGF-belta1 group showed successful hyaline-like cartilage regeneration similar to normal cartilage, which was superior to the other groups using gross examination, qualitative and quantitative histology. These findings suggested that a combination of BMMSCs/PLGA-PEG-PLGA carried with tissue growth factor (TGF-belat1) may be an alternative treatment for large osteochondral defects in high loading sites.

scholarly journals Transforming Growth Factor β1 (TGF-β1) Promotes Endothelial Cell Survival during In Vitro Angiogenesis via an Autocrine Mechanism Implicating TGF-α Signaling

2001 ◽  
Vol 21 (21) ◽  
pp. 7218-7230 ◽  
Author(s):  
Francesc Viñals ◽  
Jacques Pouysségur
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Cell Survival ◽  
Network Formation ◽  
Egf Receptor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
In Vitro Angiogenesis ◽  
Tgf Β1

ABSTRACT Mouse capillary endothelial cells (1G11 cell line) embedded in type I collagen gels undergo in vitro angiogenesis. Cells rapidly reorganize and form capillary-like structures when stimulated with serum. Transforming growth factor β1 (TGF-β1) alone can substitute for serum and induce cell survival and tubular network formation. This TGF-β1-mediated angiogenic activity depends on phosphatidylinositol 3-kinase (PI3K) and p42/p44 mitogen-activated protein kinase (MAPK) signaling. We showed that specific inhibitors of either pathway (wortmannin, LY-294002, and PD-98059) all suppressed TGF-β1-induced angiogenesis mainly by compromising cell survival. We established that TGF-β1 stimulated the expression of TGF-α mRNA and protein, the tyrosine phosphorylation of a 170-kDa membrane protein representing the epidermal growth factor (EGF) receptor, and the delayed activation of PI3K/Akt and p42/p44 MAPK. Moreover, we showed that all these TGF-β1-mediated signaling events, including tubular network formation, were suppressed by incubating TGF-β1-stimulated endothelial cells with a soluble form of an EGF receptor (ErbB-1) or tyrphostin AG1478, a specific blocker of EGF receptor tyrosine kinase. Finally, addition of TGF-α alone poorly stimulated angiogenesis; however, by reducing cell death, it strongly potentiated the action of TGF-β1. We therefore propose that TGF-β1 promotes angiogenesis at least in part via the autocrine secretion of TGF-α, a cell survival growth factor, activating PI3K/Akt and p42/p44 MAPK.

Abstract 297: Cyclic GMP Reduces Vascular Smooth Muscle Migration through Inhibition of TGF-ß1/Smad Signaling

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Jackson R Vuncannon ◽  
Joshua D Stone ◽  
Danielle N Martin ◽  
Chintamani N Joshi ◽  
Shaquria P Adderley ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Growth Factor ◽  
Vascular Smooth Muscle ◽  
Cyclic Gmp ◽  
Transforming Growth Factor ◽  
Soluble Guanylate Cyclase ◽  
Sandwich Elisa ◽  
Cell Lysates ◽  
Tgf Β1

Abnormal vascular smooth muscle (VSM) growth remains an elemental foundation of vasculoproliferative disorders including atherosclerosis and restenosis. Many second messenger, cytokine, and growth factor signals mediate control of VSM growth, and among these is transforming growth factor (TGF)-β1, a pluripotent cytokine with wide-ranging yet often opposite effects in VSM. Cyclic nucleotide signaling also exerts powerful growth control of VSM, and our previous work has helped establish a biological link between cyclic GMP and TGF-β1 in injured carotid arteries. The current study characterized the influence of cyclic GMP on TGF-β1 and its receptor-activated Smad3 in rat primary VSM cells. The heme-dependent soluble guanylate cyclase (sGC) stimulator BAY 41-2272 (BAY41) significantly increased cyclic GMP and site-specific phosphorylation of vasodilator-activated serum phosphoprotein (VASP) in manner indicative of active protein kinase G (PKG) and PKA signaling. Recombinant TGF-β1 (10 ng/ml) significantly stimulated phospho-Smad3 (Ser 423/425 ) and decreased inhibitory Smad7 in VSM cell homogenates, and using flow cytometry significantly increased cells in G 2 /M and expression of cyclins D and E and Cdk2 and Cdk4 while decreasing expression of inhibitory p21 and p27 after 24 hours compared to vehicle controls. TGF-β1 also significantly increased cell numbers compared to controls after 48 hours, thus confirming growth promoting capacities of TGF-β1 in VSM. In cell lysates double-sandwich ELISA revealed that BAY41 significantly reduces total and active TGF-β1, and Western analyses showed it significantly decreases total and phospho-Smad3 Ser423/425 expression and reduces MMP-2 and MMP-9 expression and activity (via column zymography) in both cell lysates and conditioned media after 1 and 48 hours. BAY41 also significantly reduced serum- and PDGF-stimulated cell migration between 6 and 18 hours using an in vitro scrape injury and a transwell assay. In comparison, inclusive effects of BAY41 were replicated by its prototype YC-1 and by the heme-independent sGC activator BAY 60-2770. These data clearly support growth protective capacities of cGMP in VSM and propose it operates through attenuation of TGF-β1/Smad3 signaling.

Abstract 17285: A Selective Transforming Growth Factor-β and Growth Differentiation Factor-15 Ligand Trap Attenuates Pulmonary Hypertension

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Lai-Ming Yung ◽  
Samuel D Paskin-Flerlage ◽  
Ivana Nikolic ◽  
Scott Pearsall ◽  
Ravindra Kumar ◽  
...  
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Type I ◽  
Rna Seq ◽  
Differentiation Factor ◽  
Group I ◽  
Tgf Β1

Introduction: Excessive Transforming Growth Factor-β (TGF-β) signaling has been implicated in pulmonary arterial hypertension (PAH), based on activation of TGF-β effectors and transcriptional targets in affected lungs and the ability of TGF-β type I receptor (ALK5) inhibitors to improve experimental PAH. However, clinical use of ALK5 inhibitors has been limited by cardiovascular toxicity. Hypothesis: We tested whether or not selective blockade of TGF-β and Growth Differentiation Factor (GDF) ligands using a recombinant TGFβ type II receptor extracellular domain Fc fusion protein (TGFBRII-Fc) could impact experimental PAH. Methods: Male SD rats were injected with monocrotaline (MCT) and received vehicle or TGFBRII-Fc (15 mg/kg, twice per week, i.p.). C57BL/6 mice were treated with SU-5416 and hypoxia (SUGEN-HX) and received vehicle or TGFBRII-Fc. RNA-Seq was used to profile transcriptional changes in lungs of MCT rats. Circulating levels of GDF-15 were measured in 241 PAH patients and 41 healthy controls. Human pulmonary artery smooth muscle cells were used to examine signaling in vitro . Results: TGFBRII-Fc is a selective ligand trap, inhibiting the ability of GDF-15, TGF-β1, TGF-β3, but not TGF-β2 to activate SMAD2/3 in vitro . In MCT rats, prophylactic treatment with TGFBRII-Fc normalized expression of TGF-β transcriptional target PAI-1, attenuated PAH and vascular remodeling. Delayed administration of TGFBRII-Fc in rats with established PAH at 2.5 weeks led to improved survival, decreased PAH and remodeling at 5 weeks. Similar findings were observed in SUGEN-HX mice. No valvular abnormalities were found with TGFBRII-Fc treatment. RNA-Seq revealed GDF-15 to be the most highly upregulated TGF-β ligand in the lungs of MCT rats, with only modest increases in TGF-β1 and no change in TGF-β2/3 observed, suggesting a dominant role of GDF-15 in the pathophysiology of this model. Plasma levels of GDF-15 were significantly increased in patients with diverse etiologies of WHO Group I PAH. Conclusions: These findings demonstrate that a selective TGF-β/GDF-15 trap attenuates experimental PAH, remodeling and mortality, without causing valvulopathy. These data highlight the potential role of GDF-15 as a pathogenic molecule and therapeutic target in PAH.

scholarly journals Mechanical properties and fracture dynamics of silicene membranes

2014 ◽  
Vol 16 (36) ◽  
pp. 19417-19423 ◽  
Author(s):  
T. Botari ◽  
E. Perim ◽  
P. A. S. Autreto ◽  
A. C. T. van Duin ◽  
R. Paupitz ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Temperature Dependence ◽  
Young’S Modulus ◽  
Edge Effects ◽  
Critical Strain ◽  
Young's Modulus ◽  
Stress Distributions ◽  
Fracture Dynamics ◽  
Poisson's Ratios ◽  
Poisson’S Ratios

A thorough study on the mechanical properties of silicene membranes. Young's modulus, Poisson's ratios, critical strain values, edge effects, dynamics of edge reconstructions, temperature dependence and stress distributions were investigated.

scholarly journals Knockdown of Long Noncoding RNA H19 Represses the Progress of Pulmonary Fibrosis through the Transforming Growth Factor β/Smad3 Pathway by Regulating MicroRNA 140

2019 ◽  
Vol 39 (12) ◽  
Author(s):  
Xi Wang ◽  
Zhe Cheng ◽  
Lingling Dai ◽  
Tianci Jiang ◽  
Liuqun Jia ◽  
...  
Keyword(s):  
Growth Factor ◽  
Pulmonary Fibrosis ◽  
Noncoding Rna ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Animal Experiments ◽  
A549 Cells ◽  
Transforming Growth Factor Β ◽  
Tgf Β1

ABSTRACT Long noncoding RNAs (lncRNAs) are involved in various human diseases. Recently, H19 was reported to be upregulated in fibrotic rat lung and play a stimulative role in bleomycin (BLM)-induced pulmonary fibrosis in mice. However, its expression in human fibrotic lung tissues and mechanism of action remain unclear. Here, our observations showed that H19 expression was significantly upregulated and that of microRNA 140 (miR-140) was markedly reduced in pulmonary fibrotic tissues from idiopathic pulmonary fibrosis (IPF) patients and transforming growth factor β1 (TGF-β1)-induced HBE and A549 cells. Moreover, the expression of H19 was negatively correlated with the expression of miR-140 in IPF tissues. H19 knockdown attenuated TGF-β1-induced pulmonary fibrosis in vitro. Furthermore, animal experiments showed that H19 knockdown attenuated BLM-induced pulmonary fibrosis in mice. The study of molecular mechanisms showed that H19 functioned via reduction of miR-140 expression by binding to miR-140. The increase of miR-140 inhibited TGF-β1-induced pulmonary fibrosis, and H19 upregulation diminished the inhibitory effects of miR-140 on TGF-β1-induced pulmonary fibrosis, which was involved in the TGF-β/Smad3 pathway. Taken together, our findings showed that H19 knockdown attenuated pulmonary fibrosis via the regulatory network of lncRNA H19–miR-140–TGF-β/Smad3 signaling, and H19 and miR-140 might represent therapeutic targets and early diagnostic and prognostic biomarkers for patients with pulmonary fibrosis.

scholarly journals Centrifugation Conditions in the L-PRP Preparation Affect Soluble Factors Release and Mesenchymal Stem Cell Proliferation in Fibrin Nanofibers

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2729 ◽  
Author(s):  
Melo ◽  
Luzo ◽  
Lana ◽  
Santana
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor ◽  
Platelet Rich Plasma ◽  
Clinical Practices ◽  
Soluble Factors ◽  
Tnf Α ◽  
Platelet Concentration ◽  
Tgf Β1

Leukocyte and platelet-rich plasma (L-PRP) is an autologous product that when activated forms fibrin nanofibers, which are useful in regenerative medicine. As an important part of the preparation of L-PRP, the centrifugation parameters may affect the release of soluble factors that modulate the behavior of the cells in the nanofibers. In this study, we evaluated the influences of four different centrifugation conditions on the concentration of platelets and leukocytes in L-PRP and on the anabolic/catabolic balance of the nanofiber microenvironment. Human adipose-derived mesenchymal stem cells (h-AdMSCs) were seeded in the nanofibers, and their viability and growth were evaluated. L-PRPs prepared at 100× g and 100 + 400× g released higher levels of transforming growth factor (TGF)-β1 and platelet-derived growth factor (PDGF)-BB due to the increased platelet concentration, while inflammatory cytokines interleukin (IL)-8 and tumor necrosis factor (TNF)-α were more significantly released from L-PRPs prepared via two centrifugation steps (100 + 400× g and 800 + 400× g) due to the increased concentration of leukocytes. Our results showed that with the exception of nanofibers formed from L-PRP prepared at 800 + 400× g, all other microenvironments were favorable for h-AdMSC proliferation. Here, we present a reproducible protocol for the standardization of L-PRP and fibrin nanofibers useful in clinical practices with known platelet/leukocyte ratios and in vitro evaluations that may predict in vivo results.

Selective optogenetic stimulation of fibroblasts enables quantification of hetero-cellular coupling to cardiomyocytes in a three-dimensional model of heart tissue

EP Europace ◽  
2020 ◽  
Vol 22 (10) ◽  
pp. 1590-1599
Author(s):  
Maximilian Funken ◽  
Tobias Bruegmann ◽  
Philipp Sasse
Keyword(s):  
Membrane Potential ◽  
Growth Factor ◽  
Connexin 43 ◽  
Transforming Growth Factor ◽  
Three Dimensional ◽  
Transforming Growth Factor Β1 ◽  
Resting Membrane Potential ◽  
Human Cardiomyocytes ◽  
Tgf Β1

Abstract Aims Besides providing mechanical stability, fibroblasts in the heart could modulate the electrical properties of cardiomyocytes. Here, we aim to develop a three-dimensional hetero-cellular model to analyse the electric interaction between fibroblasts and human cardiomyocytes in vitro using selective optogenetic de- or hyperpolarization of fibroblasts. Methods and results NIH3T3 cell lines expressing the light-sensitive ion channel Channelrhodopsin2 or the light-induced proton pump Archaerhodopsin were generated for optogenetic depolarization or hyperpolarization, respectively, and characterized by patch clamp. Cardiac bodies consisting of 50% fibroblasts and 50% human pluripotent stem cell-derived cardiomyocytes were analysed by video microscopy and membrane potential was measured with sharp electrodes. Myofibroblast activation in cardiac bodies was enhanced by transforming growth factor-β1 (TGF-β1)-stimulation. Connexin-43 expression was analysed by qPCR and fluorescence recovery after photobleaching. Illumination of Channelrhodopsin2 or Archaerhodopsin expressing fibroblasts induced inward currents and depolarization or outward currents and hyperpolarization. Transforming growth factor-β1-stimulation elevated connexin-43 expression and increased cell–cell coupling between fibroblasts as well as increased basal beating frequency and cardiomyocyte resting membrane potential in cardiac bodies. Illumination of cardiac bodies generated with Channelrhodopsin2 fibroblasts accelerated spontaneous beating, especially after TGF-β1-stimulation. Illumination of cardiac bodies prepared with Archaerhodopsin expressing fibroblasts led to hyperpolarization of cardiomyocytes and complete block of spontaneous beating after TGF-β1-stimulation. Effects of light were significantly smaller without TGF-β1-stimulation. Conclusion Transforming growth factor-β1-stimulation leads to increased hetero-cellular coupling and optogenetic hyperpolarization of fibroblasts reduces TGF-β1 induced effects on cardiomyocyte spontaneous activity. Optogenetic membrane potential manipulation selectively in fibroblasts in a new hetero-cellular cardiac body model allows direct quantification of fibroblast–cardiomyocyte coupling in vitro.

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