scholarly journals Regulation of Hypoxia-Induced Cell Death in Human Tenocytes

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Min Liang ◽  
Hannah R. Cornell ◽  
Nasim Zargar Baboldashti ◽  
Mark S. Thompson ◽  
Andrew J. Carr ◽  
...  
Keyword(s):  
Cellular Response ◽  
Platelet Rich Plasma ◽  
Cell Types ◽  
Antiapoptotic Proteins ◽  
Vascular Growth Factor ◽  
Protective Strategy ◽  
Normal Human ◽  
Induced Apoptosis ◽  
Oxygen Requirements

Degenerate shoulder tendons display evidence of hypoxia. However tendons are relatively avascular and not considered to have high oxygen requirements and the vulnerability of tendon cells to hypoxia is unclear. Cultured human tenocytes were exposed to hypoxia and the cellular response detected using QPCR, Western blotting, viability, and ELISA assays. We find that tenocytes respond to hypoxiain vitroby activating classical HIF-1α-driven pathways. Total hypoxia caused significant tenocyte apoptosis. Transcription factors typically involved in hypoxic response, HIF-1αand FOXO3A, were upregulated. Hypoxia caused sustained upregulation of several proapoptotic proteins known to mediate hypoxia-induced apoptosis, such as Bnip3 and Nix, but others were unchanged although they were reportedly hypoxia-sensitive in other cell types. Antiapoptotic proteins Bcl2 and Bcl-xL were unchanged by hypoxia. Normal human tenocytes expressed all isoforms of the hypoxia-induced vascular growth factor VEGF except VEGF-D. Hypoxia markedly upregulated VEGF-A mRNA, followed by increased VEGF protein secretion. However treatment with VEGF did not improve tenocyte survival. As a protective strategy for tenocytes at risk of hypoxic death we added prosurvival growth factors insulin or platelet rich plasma (PRP). Both agents strongly protected tenocytes from hypoxia-induced death over 48 h, suggesting possible efficacy in the acute postrupture tendon or integrating graft.

scholarly journals Effects of Platelet-Rich Plasma on Cellular Populations of the Central Nervous System: The Influence of Donor Age

2021 ◽  
Vol 22 (4) ◽  
pp. 1725
Author(s):  
Diego Delgado ◽  
Ane Miren Bilbao ◽  
Maider Beitia ◽  
Ane Garate ◽  
Pello Sánchez ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Cellular Response ◽  
Platelet Rich Plasma ◽  
Biological Response ◽  
In Vitro Models ◽  
Molecular Composition ◽  
Cellular Models ◽  
The Central Nervous System

Platelet-rich plasma (PRP) is a biologic therapy that promotes healing responses across multiple medical fields, including the central nervous system (CNS). The efficacy of this therapy depends on several factors such as the donor’s health status and age. This work aims to prove the effect of PRP on cellular models of the CNS, considering the differences between PRP from young and elderly donors. Two different PRP pools were prepared from donors 65–85 and 20–25 years old. The cellular and molecular composition of both PRPs were analyzed. Subsequently, the cellular response was evaluated in CNS in vitro models, studying proliferation, neurogenesis, synaptogenesis, and inflammation. While no differences in the cellular composition of PRPs were found, the molecular composition of the Young PRP showed lower levels of inflammatory molecules such as CCL-11, as well as the presence of other factors not found in Aged PRP (GDF-11). Although both PRPs had effects in terms of reducing neural progenitor cell apoptosis, stabilizing neuronal synapses, and decreasing inflammation in the microglia, the effect of the Young PRP was more pronounced. In conclusion, the molecular composition of the PRP, conditioned by the age of the donors, affects the magnitude of the biological response.

E-cadherin is the major mediator of human melanocyte adhesion to keratinocytes in vitro

1994 ◽  
Vol 107 (4) ◽  
pp. 983-992 ◽  
Author(s):  
A. Tang ◽  
M.S. Eller ◽  
M. Hara ◽  
M. Yaar ◽  
S. Hirohashi ◽  
...  
Keyword(s):  
Cell Types ◽  
Melanoma Metastasis ◽  
Normal Keratinocytes ◽  
Human Melanocyte ◽  
Human Melanocytes ◽  
Dependent Cell ◽  
Normal Human ◽  
Pre Treatment ◽  
E Cadherin

E- and P-cadherin are calcium (Ca2+)-dependent cell adhesion molecules important in the morphogenesis and maintenance of skin structure. By use of flow cytometry and specific antibodies, we now show that cultured human melanocytes express E- and P-cadherin on their surfaces, and that these molecules have the same characteristics as reported for other cell types. Specifically, melanocyte cadherins are sensitive to trypsin digestion in the absence of Ca2+ and are protected from trypsin degradation by Ca2+, and are functional at 37 degrees C but not at 4 degrees C. We further show that melanocytes contain mRNA transcripts encoding both E- and P-cadherin. Adhesion of cultured melanocytes to keratinocyte monolayers is abolished by pre-treatment of the melanocytes with trypsin/EDTA, which degrades E- and P-cadherins, is greatly reduced by anti-E-cadherin antibodies and is slightly reduced by antibodies to P-cadherin, alpha 2, alpha 3 and beta 1 integrins. In contrast to normal melanocytes, eight of nine melanoma cell lines lacked E-cadherin (or expressed markedly reduced levels) and five were negative for P-cadherin. Melanoma cells also failed to adhere to keratinocyte monolayers. These results demonstrate that normal human melanocytes express functional E- and P-cadherin and that E-cadherin is primarily responsible for adhesion of human melanocytes to keratinocytes in vitro. In addition, transformed melanocytes express markedly reduced levels of E- and P-cadherin, and exhibit decreased affinity for normal keratinocytes in vitro, suggesting that loss of cadherins may play a role in melanoma metastasis.

scholarly journals Expression of TAL-1 proteins in human tissues

Blood ◽  
1995 ◽  
Vol 85 (3) ◽  
pp. 675-684 ◽  
Author(s):  
K Pulford ◽  
N Lecointe ◽  
K Leroy-Viard ◽  
M Jones ◽  
D Mathieu-Mahul ◽  
...  
Keyword(s):  
Molecular Weight ◽  
T Cell ◽  
Cell Lines ◽  
Fetal Liver ◽  
Cell Types ◽  
Human Tissues ◽  
Aberrant Expression ◽  
Erythroid Precursor ◽  
Normal Human

Rearrangement of the tal-1 gene (also known as SCL or TCL-5) occurs in at least 25% of T-cell acute lymphoblastic leukemias (T-ALLs) and results in the aberrant expression of tal-1 mRNA in the neoplastic cells. Also, tal-1 mRNA is constitutively expressed in erythroid precursors and megakaryocytes. This report describes a direct immunocytochemical study of the distribution and localization of TAL-1 protein in normal human tissues and cell lines using four monoclonal antibodies raised against recombinant TAL-1 proteins. One of these reagents recognizes a protein of 41 kD molecular weight in in vitro- translated TAL-1 proteins, two others recognize proteins of 39 and 41 kD molecular weight, and the fourth antibody also recognizes a TAL-1 protein of 22 kD in addition to the 39- and 41-kD proteins. These anti- TAL-1 antibodies label the nuclei of erythroid precursor cells and megakaryocytes in fetal liver and adult bone marrow. The punctate pattern of nuclear labeling suggests that TAL-1 may comprise part of a novel nuclear structure, similar to that recently found for the PML protein. The nuclei of T cell lines known to express mRNA encoding the full-length TAL-1 protein (eg, CCRF-CEM, RPMI 8402, and Jurkat) are also labeled. A study of normal human tissues (including thymus) showed labeling of smooth muscle, some tissue macrophages, and endothelial cells. TAL-1 protein is undetectable in other cell types. These reagents may play an important role in the diagnosis of T-ALL and could also be used in the context of lymphoma diagnosis on routinely fixed material.

scholarly journals Fas-mediated apoptosis in cultured human eosinophils

Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2822-2830 ◽  
Author(s):  
A Druilhe ◽  
Z Cai ◽  
S Haile ◽  
S Chouaib ◽  
M Pretolani
Keyword(s):  
Tumor Necrosis Factor Receptor ◽  
Antigen Expression ◽  
Cell Types ◽  
Time Dependent ◽  
Cross Linking ◽  
Fas Antigen ◽  
Transmembrane Glycoprotein ◽  
Numerous Cell ◽  
Induced Apoptosis

Previous studies have shown that cytokine-dependent eosinophils undergo apoptosis, yet the mechanisms governing this phenomenon remain obscure. Fas antigen is a transmembrane glycoprotein belonging to the tumor necrosis factor receptor family. Cross-linking of Fas antigen in numerous cell types leads to apoptosis. In the present study, we examined the potential role of Fas antigen in the apoptosis of purified blood eosinophils from healthy donors. Cytokine-deprived eosinophils exhibited a time-dependent loss in viability, accompanied by an increase in the number of apoptotic nuclei and in the expression of Fas antigen and its mRNA, as shown by flow cytometry and reverse transcriptase-polymerase chain reaction, respectively. Cross-linking of Fas antigen with an agonistic anti-Fas monoclonal antibody (MoAb) induced a dose- and time-dependent increase in the number of apoptotic nuclei. Furthermore, using an in vitro coculture system, we showed engulfment of anti-Fas MoAb-treated eosinophils by monocyte-derived macrophages. Finally, incubation of eosinophils with the corticosteroid, dexamethasone, induced apoptosis and augmented that triggered by anti-Fas MoAb. Together, these observations suggest that Fas antigen expression and activation is involved in the apoptosis of human eosinophils and may contribute to the resolution of inflammatory allergic reactions in which eosinophil accumulation is a prominent feature.

Arsenic induces apoptosis of multidrug-resistant human myeloid leukemia cells that express Bcr-Abl or overexpress MDR, MRP, Bcl-2, or Bcl-xL

Blood ◽  
2000 ◽  
Vol 95 (3) ◽  
pp. 1014-1022 ◽  
Author(s):  
Charles Perkins ◽  
Caryn N. Kim ◽  
Guofu Fang ◽  
Kapil N. Bhalla
Keyword(s):  
Myeloid Leukemia ◽  
Blast Crisis ◽  
K562 Cells ◽  
Cell Types ◽  
Multidrug Resistant ◽  
Leukemia Cells ◽  
Protein Levels ◽  
Growth Inhibitory ◽  
Induced Apoptosis

We investigated the in vitro growth inhibitory and apoptotic effects of clinically achievable concentrations of As2O3 (0.5 to 2.0 μmol/L) against human myeloid leukemia cells known to be resistant to a number of apoptotic stimuli. These included chronic myelocytic leukemia (CML) blast crisis K562 and HL-60/Bcr-Abl cells, which contain p210 and p185 Bcr-Abl, respectively, and HL-60 cell types that overexpress Bcl-2 (HL-60/Bcl-2), Bcl-xL(HL-60/Bcl-xL), MDR (HL-60/VCR), or MRP (HL-60/AR) protein. The growth-inhibitory IC50 values for As2O3 treatment for 7 days against all these cell types ranged from 0.8 to 1.5 μmol/L. Exposure to 2 μmol/L As2O3 for 7 days induced apoptosis of all cell types, including HL-60/Bcr-Abl and K562 cells. This was associated with the cytosolic accumulation of cyt c and preapoptotic mitochondrial events, such as the loss of inner membrane potential (▵Ψm) and the increase in reactive oxygen species (ROS). Treatment with As2O3 (2 μmol/L) generated the activities of caspases, which produced the cleavage of the BH3 domain containing proapoptotic Bid protein and poly (ADP-ribose) polymerase. Significantly, As2O3-induced apoptosis of HL-60/Bcr-Abl and K562 cells was associated with a decline in Bcr-Abl protein levels, without any significant alterations in the levels of Bcl-xL, Bax, Apaf-1, Fas, and FasL. Although As2O3 treatment caused a marked increase in the expression of the myeloid differentiation marker CD11b, it did not affect Hb levels in HL-60/Bcr-Abl, K562, or HL-60/neo cells. However, in these cells, As2O3 potently induced hyper-acetylation of the histones H3 and H4. These findings characterize As2O3 as a growth inhibiting and apoptosis-inducing agent against a variety of myeloid leukemia cells resistant to multiple apoptotic stimuli.

scholarly journals Merging Microfluidics with Microtitre Technology for More Efficient Drug Discovery

2008 ◽  
Vol 13 (5) ◽  
pp. 275-279 ◽  
Author(s):  
Nicole V. Tolan ◽  
Luiza I. Genes ◽  
Dana M. Spence
Keyword(s):  
Cellular Response ◽  
Simultaneous Detection ◽  
Drug Efficacy ◽  
Cell Types ◽  
Microtitre Plate ◽  
Multiple Components ◽  
Multiple Cell ◽  
Improve Blood Flow

Detecting multiple components from a single red blood cell (RBC) sample within a flow-based system in less than 20 min will enable improved in vitro determinations of drug efficacy and cellular response to administered drugs. Here, an example of an improved in vitro measurement involving iloprost, a pharmaceutical reported to improve blood flow, has been determined by incorporating multiple cell types onto a single device. The method allows fluid flow to address individual rows of wells contained within an 18-well microfluidic array that serves as a precursor to a 96-well microtitre plate device. The ability to better mimic the in vivo circulation by incorporating the flow of blood components, coupled with simultaneous detection and laboratory automation in place for microtitre plates, suggests that the microfluidic array presented here will allow for improved mechanistic drug research studies. Using fluorescence microscopy, concentrations of multiple metabolites present within the RBC can also be determined using the microfluidic array. The current progress toward using this device for personalized medicine is presented here.

scholarly journals Growth factor-dependent inhibition of normal hematopoiesis by N-ras antisense oligodeoxynucleotides.

1992 ◽  
Vol 175 (3) ◽  
pp. 743-750 ◽  
Author(s):  
T Skorski ◽  
C Szczylik ◽  
M Z Ratajczak ◽  
L Malaguarnera ◽  
A M Gewirtz ◽  
...  
Keyword(s):  
Cell Types ◽  
Antisense Oligodeoxynucleotides ◽  
Antisense Oligodeoxynucleotide ◽  
Semisolid Medium ◽  
Gm Csf ◽  
Cd34 Cells ◽  
Dependent Inhibition ◽  
Normal Human ◽  
Macrophage Colony

To determine whether N-ras expression is required at specific stages of the process of in vitro normal human hematopoiesis, adherent- and T lymphocyte-depleted mononuclear marrow cells (A-T-MNC) or highly purified progenitors (CD34+ cells) were cultured in semisolid medium, under conditions that favor the growth of specific progenitor cell types, after exposure to N-ras sense and antisense oligodeoxynucleotides. N-ras antisense, but not sense, oligodeoxynucleotide treatment of A-T-MNC and CD34+ cells resulted in a significantly decreased number of granulocyte/macrophage colony-forming units (CFU-GM) induced by interleukin 3 (IL-3) or granulocyte/macrophage colony-stimulating factor (GM-CSF) and of macrophage colonies (CFU-M) induced by M-CSF, but not of granulocytic colonies induced with G-CSF or IL-5. However, the same treatment significantly inhibited colony formation induced by each of the above factors in combination with IL-3. Megakaryocytic colony (CFU-Meg) formation from A-T-MNC or CD34+ cells in the presence of IL-6 + IL-3 + erythropoietin (Epo) was also markedly decreased after antisense oligodeoxynucleotide treatment. Erythroid colonies derived from A-T-MNC in the presence of Epo (CFU-E) were not inhibited upon antisense treatment, whereas those arising from A-T-MNC or CD34+ cells in the presence of IL-3 + Epo (BFU-E) were markedly affected. These results are consistent with the hypothesis that distinct signal transduction pathways, involving N-ras or not, are activated by different growth factors in different hematopoietic progenitor cells.

scholarly journals Expression of c-myb and B-myb, but not A-myb, correlates with proliferation in human hematopoietic cells

Blood ◽  
1991 ◽  
Vol 77 (1) ◽  
pp. 149-158 ◽  
Author(s):  
J Golay ◽  
A Capucci ◽  
M Arsura ◽  
M Castellano ◽  
V Rizzo ◽  
...  
Keyword(s):  
B Cells ◽  
B Lymphocytes ◽  
Cellular Proliferation ◽  
Cell Types ◽  
T And B Lymphocytes ◽  
Thymidine Uptake ◽  
Mitogenic Stimulation ◽  
Myb Gene ◽  
Normal Human

Abstract The steady-state expression of three members of the myb family of genes, c-myb, B-myb, and A-myb, was studied in four purified normal human hematopoietic cell types, ie, T and B lymphocytes, monocytes, and granulocytes. The c-myb proto-oncogene is low to undetectable in resting T and B lymphocytes and shows a biphasic induction in both cell types after mitogenic stimulation, with a first peak at 3 hours and a second and stronger induction at 44 to 72 hours. Study of the B-myb gene showed that this gene is low to undetectable in resting T or B cells and is strongly induced after mitogenic stimulation with a peak between 44 and 72 hours in both cell types. Finally, the A-myb gene shows a pattern of expression in lymphocytes different from that of c- myb and B-myb. It is expressed in resting T lymphocytes and its levels gradually decrease after mitogenic stimulation to become undetectable at 48 hours. It is also expressed in a subpopulation of large B lymphocytes but not in in vitro activated B cells. Neither of the three members of the myb family of genes was expressed in monocytes and granulocytes, even after functional activation of these cells. Taken together, these data bring further evidence for the role of c-myb in cellular proliferation and on the basis of the kinetics of its induction relative to thymidine uptake, we hypothesize that it may have a role during G1 progression in addition to that already documented for entry into S phase. Furthermore, our studies indicate that another member of the myb family of genes, B-myb, may also be involved in cellular proliferation, because its expression correlates with the induction of mitogenesis.

Oxygen consumption by human and rodent striated muscle in vitro

1976 ◽  
Vol 230 (1) ◽  
pp. 34-40 ◽  
Author(s):  
WW Hofmann
Keyword(s):  
Oxygen Consumption ◽  
Striated Muscle ◽  
Osmotic Shock ◽  
Electrode System ◽  
Pharmacological Tests ◽  
Normal Human ◽  
Oxygen Requirements ◽  
Major Surface ◽  
Muscle Responses

Oxygen consumption has been measured in human and rodent striated muscle in vitro with a platinum-silver electrode system. The effects of excess potassium, caffeine, insulin, osmotic shock, halothane, and Na-pump blockade have been investigated and the differences from amphibian muscle responses are outlined. It has been found that normal human muscle, like that of rodents, is relatively indifferent to major surface depolarization and osmotic shock, as far as oxygen requirements are concerned. Surgical damage to muscle fibers causes them to react unpredictably to pharmacological tests. The results in normal muscles may be of use in the further study of certain muscular diseases.

scholarly journals Wnt/β-Catenin and Wnt5a/Ca2+ Pathways Regulate Proliferation and Apoptosis of Keratinocytes in Psoriasis Lesions

2015 ◽  
Vol 36 (5) ◽  
pp. 1890-1902 ◽  
Author(s):  
Yanfei Zhang ◽  
Chen Tu ◽  
Dingwei Zhang ◽  
Yan Zheng ◽  
Zhenhui Peng ◽  
...  
Keyword(s):  
Human Keratinocytes ◽  
Mrna Levels ◽  
Protein Levels ◽  
Proliferation And Apoptosis ◽  
Genes Encoding ◽  
Keratinocyte Cell ◽  
Normal Human ◽  
Induced Apoptosis ◽  
Psoriatic Lesions

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.

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