Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
Add more filters










Publication year range
1.
JAAPA ; 37(1): 1, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38128140
2.
JAAPA ; 36(11): 1, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37884041
3.
J Med Imaging Radiat Sci ; 54(1): 104-116, 2023 03.
Article in English | MEDLINE | ID: mdl-36535859

ABSTRACT

BACKGROUND: Artificial Intelligence (AI) technologies have already started impacting clinical practice across various settings worldwide, including the radiography profession. This study is aimed at exploring a world-wide view on AI technologies in relation to knowledge, perceptions, and expectations of radiography professionals. METHODS: An online survey (hosted on Qualtrics) on key AI concepts was open to radiography professionals worldwide (August 1st to December 31st 2020). The survey sought both quantitative and qualitative data on topical issues relating to knowledge, perceptions, and expectations in relation to AI implementation in radiography practice. Data obtained was analysed using the Statistical Package for Social Sciences (SPSS) (v.26) and the six-phase thematic analysis approach. RESULTS: A total of 314 valid responses were obtained with a fair geographical distribution. Of the respondents, 54.1% (157/290) were from North America and were predominantly clinical practicing radiographers (60.5%, 190/314). Our findings broadly relate to different perceived benefits and misgivings/shortcomings of AI implementation in radiography practice. The benefits relate to enhanced workflows and optimised workstreams while the misgivings/shortcomings revolve around de-skilling and impact on patient-centred care due to over-reliance on advanced technology following AI implementation. DISCUSSION: Artificial intelligence is a tool but to operate optimally it requires human input and validation. Radiographers working at the interface between technology and the patient are key stakeholders in AI implementation. Lack of training and of transparency of AI tools create a mixed response of radiographers when they discuss their perceived benefits and challenges. It is also possible that their responses are nuanced by different regional and geographical contexts when it comes to AI deployment. Irrespective of geography, there is still a lot to be done about formalised AI training for radiographers worldwide. This is a vital step to ensure safe and effective AI implementation, adoption, and faster integration into clinical practice by healthcare workers including radiographers. CONCLUSION: Advancement of AI technologies and implementation should be accompanied by proportional training of end-users in radiography and beyond. There are many benefits of AI-enabled radiography workflows and improvement on efficiencies but equally there will be widespread disruption of traditional roles and patient-centred care, which can be managed by a well-educated and well-informed workforce.


Subject(s)
Artificial Intelligence , Motivation , Humans , Radiography , Workforce , Surveys and Questionnaires
5.
JAAPA ; 35(7): 57-59, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35762958
7.
JAAPA ; 35(3): 1, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35192559
9.
J Drug Deliv ; 2016: 2407459, 2016.
Article in English | MEDLINE | ID: mdl-27800184

ABSTRACT

Objective. To evaluate thermosensitive, biodegradable pentablock copolymers (PTSgel) for sustained release and integrity of a therapeutic protein when injected subcutaneously. Materials and Methods. Five PTSgels with PEG-PCL-PLA-PCL-PEG block arrangements were synthesized. In vitro release of IgG from PTSgels and concentrations was evaluated at 37°C. Released IgG integrity was characterized by SDS-PAGE. In vitro disintegration for 10GH PTSgel in PBS was monitored at 37°C over 72 days using gravimetric loss and GPC analysis. Near-infrared IgG in PTSgel was injected subcutaneously and examined by in vivo imaging and histopathology for up to 42 days. Results. IgG release was modulated from approximately 7 days to more than 63 days in both in vitro and in vivo testing by varying polymer composition, concentration of PTSgel aqueous solution, and concentration of IgG. Released IgG in vitro maintained structural integrity by SDS-PAGE. Subcutaneous PTSgels were highly biocompatible and in vitro IgG release occurred in parallel with the disappearance of subcutaneous gel in vivo. Conclusions. Modulation of release of biologics to fit the therapeutic need can be achieved by varying the biocompatible and biodegradable PTSgel composition. Release of IgG parallels disappearance of the polymeric gel; hence, little or no PTSgel remains after drug release is complete.

10.
J Histochem Cytochem ; 64(2): 99-111, 2016 02.
Article in English | MEDLINE | ID: mdl-26538547

ABSTRACT

The wingless (Wnt) family of signaling ligands contributes significantly to lung development and is highly expressed in patients with usual interstitial pneumonia (UIP). We sought to define the cellular distribution of Wnt5A in the lung tissue of patients with idiopathic pulmonary fibrosis (IPF) and the signaling ligands that control its expression in human lung fibroblasts and IPF myofibroblasts. Tissue sections from 40 patients diagnosed with IPF or UIP were probed for the immunolocalization of Wnt5A. Further, isolated lung fibroblasts from normal or IPF human lungs, adenovirally transduced for the overexpression or silencing of Wnt7B or treated with TGF-ß1 or its inhibitor, were analyzed for Wnt5A protein expression. Wnt5A was expressed in IPF lungs by airway and alveolar epithelium, smooth muscle cells, endothelium, and myofibroblasts of fibroblastic foci and throughout the interstitium. Forced overexpression of Wnt7B with or without TGF-ß1 treatment significantly increased Wnt5A protein expression in normal human smooth muscle cells and fibroblasts but not in IPF myofibroblasts where Wnt5A was already highly expressed. The results demonstrate a wide distribution of Wnt5A expression in cells of the IPF lung and reveal that it is significantly increased by Wnt7B and TGF-ß1, which, in combination, could represent key signaling pathways that modulate the pathogenesis of IPF.


Subject(s)
Fibroblasts/pathology , Idiopathic Pulmonary Fibrosis/pathology , Lung/pathology , Proto-Oncogene Proteins/analysis , Transforming Growth Factor beta/analysis , Wnt Proteins/analysis , Cells, Cultured , Fibroblasts/metabolism , Gene Expression Regulation , Gene Silencing , Humans , Idiopathic Pulmonary Fibrosis/genetics , Idiopathic Pulmonary Fibrosis/metabolism , Lung/metabolism , Myocytes, Smooth Muscle/metabolism , Myofibroblasts/metabolism , Myofibroblasts/pathology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/metabolism , Up-Regulation , Wnt Proteins/genetics , Wnt Proteins/metabolism , Wnt-5a Protein
11.
Exp Lung Res ; 41(9): 499-513, 2015.
Article in English | MEDLINE | ID: mdl-26495958

ABSTRACT

PURPOSE/AIM: Previous studies have indicated that the sulfated polysaccharide heparin has anti-inflammatory effects. However, the mechanistic basis for these effects has not been fully elucidated. MATERIALS AND METHODS: NCI-H292 (mucoepidermoid) and HBE-1 (normal) human bronchial epithelial cells were treated with LPS alone or in the presence of high-molecular-weight (HMW) fully sulfated heparin or desulfated HMW heparin. Cells were harvested to examine the phosphorylation levels of ERK1/2, p38, and NF-kB p65 and COX-2 protein expression by Western blot and gene expression of both COX-2 and CXCL-8 by TaqMan qRT-PCR. RESULTS: Heparin is known to exert an influence on receptor-mediated signaling through its ability to both potentiate and inhibit the receptor-ligand interaction, depending upon its concentration. In H292 cells, fully-sulfated HMW heparin significantly reduced LPS-induced gene expression of both COX-2 and CXCL-8 for up to 48 hours, while desulfated heparin had little to no significant suppressive effect on signaling or on COX-2 gene or protein expression. Desulfated heparin, initially ineffective at preventing LPS-induced CXCL8 up-regulation, reduced CXCL8 transcription at 24 hours. In contrast, in normal HBE-1 cells, fully sulfated heparin significantly suppressed only ERK signaling, COX-2 gene expression at 12 hours, and CXCL-8 gene expression at 6 and 12 hours, while desulfated heparin had no significant effects on LPS-stimulated signaling or on gene or protein expression. Sulfation determines heparin's influence and may reflect the moderating role of GAG sulfation in lung injury and health. CONCLUSIONS: Heparin's anti-inflammatory effects result from its nonspecific suppression of signaling and gene expression and are determined by its sulfation.


Subject(s)
Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Heparin/pharmacology , Lipopolysaccharides/toxicity , Respiratory Mucosa/drug effects , Respiratory Mucosa/metabolism , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cell Line , Gene Expression/drug effects , Glycosaminoglycans/chemistry , Glycosaminoglycans/metabolism , Heparin/chemistry , Humans , Interleukin-8/genetics , Interleukin-8/metabolism , MAP Kinase Signaling System/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Respiratory Mucosa/cytology
12.
PLoS One ; 9(4): e93413, 2014.
Article in English | MEDLINE | ID: mdl-24690998

ABSTRACT

It is generally accepted that the surfactant-producing pulmonary alveolar epithelial type II (AT2) cell acts as the progenitor of the type I (AT1) cell, but the regulatory mechanisms involved in this relationship remain the subject of active investigation. While previous studies have established a number of specific markers that are expressed during transdifferentiation from AT2 to AT1 cells, we hypothesized that additional, previously unrecognized, signaling pathways and relevant cellular functions are transcriptionally regulated at early stages of AT2 transition. In this study, a discovery-based gene expression profile analysis was undertaken of freshly isolated human AT2 (hAT2) cells grown on extracellular matrix (ECM) substrata known to either support (type I collagen) or retard (Matrigel) the early transdifferentiation process into hAT1-like cells over the first three days. Cell type-specific expression patterns analyzed by Illumina Human HT-12 BeadChip yielded over 300 genes that were up- or down-regulated. Candidate genes significantly induced or down-regulated during hAT2 transition to hAT1-like cells compared to non-transitioning hAT2 cells were identified. Major functional groups were also recognized, including those of signaling and cytoskeletal proteins as well as genes of unknown function. Expression of established signatures of hAT2 and hAT1 cells, such as surfactant proteins, caveolin-1, and channels and transporters, was confirmed. Selected novel genes further validated by qRT-PCR, protein expression analysis, and/or cellular localization included SPOCK2, PLEKHO1, SPRED1, RAB11FIP1, PTRF/CAVIN-1 and RAP1GAP. These results further demonstrate the utility of genome-wide analysis to identify relevant, novel cell type-specific signatures of early ECM-regulated alveolar epithelial transdifferentiation processes in vitro.


Subject(s)
Alveolar Epithelial Cells/cytology , Alveolar Epithelial Cells/metabolism , Cell Transdifferentiation/genetics , Gene Expression Profiling , Gene Expression , Genome-Wide Association Study , Caveolin 1/genetics , Caveolin 1/metabolism , Cells, Cultured , Gene Expression Regulation , Humans , Protein Transport , Reproducibility of Results , Time Factors , Transcriptome
13.
J Histochem Cytochem ; 61(9): 671-9, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23797050

ABSTRACT

The fibroblast growth factor (FGF) family of signaling ligands contributes significantly to lung development and maintenance in the adult. FGF9 is involved in control of epithelial branching and mesenchymal proliferation and expansion in developing lungs. However, its activity and expression in the normal adult lung and by epithelial and interstitial cells in fibroproliferative diseases like idiopathic pulmonary fibrosis (IPF) are unknown. Tissue samples from normal organ donor human lungs and those of a cohort of patients with mild to severe IPF were sectioned and stained for the immunolocalization of FGF9. In normal lungs, FGF9 was confined to smooth muscle surrounding airways, alveolar ducts and sacs, and blood vessels. In addition to these same sites, lungs of IPF patients expressed FGF9 in a population of myofibroblasts within fibroblastic foci, hypertrophic and hyperplastic epithelium of airways and alveoli, and smooth muscle cells surrounding vessels embedded in thickened interstitium. The results demonstrate that FGF9 protein increased in regions of active cellular hyperplasia, metaplasia, and fibrotic expansion of IPF lungs, and in isolated human lung fibroblasts treated with TGF-ß1 and/or overexpressing Wnt7B. The cellular distribution and established biologic activity of FGF9 make it a potentially strong candidate for contributing to the progression of IPF.


Subject(s)
Fibroblast Growth Factor 9/analysis , Idiopathic Pulmonary Fibrosis/pathology , Lung/pathology , Adult , Cells, Cultured , Fibroblast Growth Factor 9/metabolism , Humans , Idiopathic Pulmonary Fibrosis/metabolism , Immunohistochemistry , Lung/metabolism , Lung/ultrastructure , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Myocytes, Smooth Muscle/ultrastructure , Myofibroblasts/metabolism , Myofibroblasts/pathology , Myofibroblasts/ultrastructure
14.
Toxicol Appl Pharmacol ; 265(1): 27-42, 2012 Nov 15.
Article in English | MEDLINE | ID: mdl-23000194

ABSTRACT

Environmental exposure to cadmium is known to cause damage to alveolar epithelial cells of the lung, impair their capacity to repair, and result in permanent structural alterations. Cell surface heparan sulfate proteoglycans (HSPGs) can modulate cell responses to injury through their interactions with soluble effector molecules. These interactions are often sulfate specific, and the removal of sulfate groups from HS side chains could be expected to influence cellular injury, such as that caused by exposure to cadmium. The goal of this study was to define the role 6-O-sulfate plays in cellular responses to cadmium exposure in two pulmonary epithelial cancer cell lines (H292 and A549) and in normal human primary alveolar type II (hAT2) cells. Sulfate levels were modified by transduced transient over-expression of 6-O-endosulfatase (HSulf-1), a membrane-bound enzyme which specifically removes 6-O-sulfate groups from HSPG side chains. Results showed that cadmium decreased cell viability and activated apoptosis pathways at low concentrations in hAT2 cells but not in the cancer cells. HSulf-1 over-expression, on the contrary, decreased cell viability and activated apoptosis pathways in H292 and A549 cells but not in hAT2 cells. When combined with cadmium, HSulf-1 over-expression further decreased cell viability and exacerbated the activation of apoptosis pathways in the transformed cells but did not add to the toxicity in hAT2 cells. The finding that HSulf-1 sensitizes these cancer cells and intensifies the injury induced by cadmium suggests that 6-O-sulfate groups on HSPGs may play important roles in protection against certain environmental toxicants, such as heavy metals.


Subject(s)
Cadmium/toxicity , Lung/pathology , Sulfotransferases/biosynthesis , Sulfotransferases/physiology , Adenoviridae/genetics , Apoptosis/drug effects , Blotting, Western , Cell Count , Cell Line, Tumor , Cell Survival/drug effects , Cell Transformation, Neoplastic/drug effects , Coloring Agents , Down-Regulation/drug effects , Heparan Sulfate Proteoglycans/pharmacology , Humans , In Situ Nick-End Labeling , Lac Operon/genetics , Polymerase Chain Reaction , Respiratory Mucosa/pathology , Tetrazolium Salts , Thiazoles , Transduction, Genetic , Up-Regulation/drug effects
15.
Respir Res ; 13: 69, 2012 Aug 08.
Article in English | MEDLINE | ID: mdl-22873647

ABSTRACT

BACKGROUND: Heparan sulfate proteoglycans (HSPGs) modulate the binding and activation of signaling pathways of specific growth factors, such as fibroblast growth factor-2 (FGF-2). Human endosulfatase 1 (HSULF-1) is an enzyme that selectively removes 6-O sulfate groups from HS side chains and alter their level and pattern of sulfation and thus biological activity. It is known that HSULF-1 is expressed at low levels in some cancer cell lines and its enhanced expression can inhibit cancer cell growth or induce apoptosis, but the mechanism(s) involved has not been identified. METHODS: HSULF-1 mRNA expression was assessed in five normal cells (primary human lung alveolar type 2 (hAT2) cells, adult lung fibroblasts (16Lu), fetal lung fibroblasts (HFL), human bronchial epithelial cells (HBE), and primary human lung fibroblasts (HLF)) and five lung cancer cell lines (A549, H292, H1975, H661, and H1703) using quantitative real time polymerase chain reaction (qRT-PCR). H292 and hAT2 cells over-expressing HSULF-1 were analyzed for cell viability, apoptosis, and ERK/Akt signaling, by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, and Western Blot, respectively. Apoptosis pathway activation was confirmed by PCR array in hAT2, H292, and A549 cells. RESULTS: HSULF-1 was expressed at a significantly lower level in epithelial cancer cell lines compared to normal cells. Infection with recombinant adenovirus for HSULF-1 over-expression resulted in decreased cell viability in H292 cells, but not in normal hAT2 cells. HSULF-1 over-expression induced apoptosis in H292 cells, but not in hAT2 cells. In addition, apoptosis pathways were activated in both H292 and A549 cells, but not in hAT2 cells. HSULF-1 over-expression reduced ERK and Akt signaling activation in H292 cells, which further demonstrated its inhibitory effects on signaling related to proliferation. CONCLUSIONS: These results indicate that HSULF-1 is expressed at lower levels in H292 lung cancer cells than in normal human alveolar cells and that its over-expression reduced cell viability in H292 cells by inducing apoptotic pathways, at least in part by inhibiting ERK/Akt signaling. We hypothesize that HSULF-1 plays important roles in cancer cells and functions to modify cell signaling, inhibit cancer proliferation, and promote cancer cell death.


Subject(s)
Apoptosis/genetics , Lung Neoplasms/enzymology , Lung/enzymology , MAP Kinase Signaling System/genetics , Proto-Oncogene Proteins c-akt/metabolism , Sulfotransferases/metabolism , Cell Line, Tumor , Cell Survival , Epithelial Cells/enzymology , Humans , In Situ Nick-End Labeling , Real-Time Polymerase Chain Reaction , Signal Transduction
16.
Respir Res ; 13: 62, 2012 Jul 28.
Article in English | MEDLINE | ID: mdl-22838404

ABSTRACT

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial pneumonia causing a loss of respiratory surface area due to a proliferative fibrotic response involving hyperplastic, hypertrophic, and metaplastic epithelium, cystic honeycomb change, septal expansion, and variable inflammation. Wnt (wingless) signaling glycoproteins are known to be involved in lung development and tissue repair, and are up-regulated in patients with IPF. Based on previous qRT-PCR data showing increased Wnt7B in lungs of IPF patients, a systematic, quantitative examination of its tissue site distribution was undertaken. METHODS: Tissue samples from the Lung Tissue Research Consortium (LTRC) of 39 patients diagnosed with mild to severe IPF/usual interstitial pneumonia (UIP) and 19 normal patients were examined for the immunolocalization of Wnt7B. RESULTS: In normal lung, moderate Wnt7B reactivity was confined to airway epithelium, smooth muscle of airways and vasculature, and macrophages. IPF lung showed strong Wnt7B reactivity in fibroblastic foci, dysplastic airway and alveolar epithelium, and in highly discrete subepithelial, basement membrane-associated regions. All reactive sites were sized and counted relative to specific microscopic regions. Those in the subepithelial sites were found in significantly greater numbers and larger relative area compared with the others. No reactive sites were present in normal patient controls. CONCLUSIONS: The results demonstrate Wnt7B to be expressed at high concentrations in regions of active hyperplasia, metaplasia, and fibrotic change in IPF patients. In this context and its previously established biologic activities, Wnt7B would be expected to be of potential importance in the pathogenesis of IPF.


Subject(s)
Fibroblasts/pathology , Idiopathic Pulmonary Fibrosis/metabolism , Idiopathic Pulmonary Fibrosis/pathology , Wnt Proteins/metabolism , Aged , Aged, 80 and over , Basement Membrane/pathology , Female , Humans , Macrophages/pathology , Male , Middle Aged , Muscle, Smooth/pathology , Respiratory Mucosa/pathology , Respiratory System/blood supply , Respiratory System/pathology , Severity of Illness Index , Wnt Proteins/analysis
17.
Chem Biol ; 18(2): 252-63, 2011 Feb 25.
Article in English | MEDLINE | ID: mdl-21338922

ABSTRACT

Disruptions of anatomical left-right asymmetry result in life-threatening heterotaxic birth defects in vital organs. We performed a small molecule screen for left-right asymmetry phenotypes in Xenopus embryos and discovered a pyridine analog, heterotaxin, which disrupts both cardiovascular and digestive organ laterality and inhibits TGF-ß-dependent left-right asymmetric gene expression. Heterotaxin analogs also perturb vascular development, melanogenesis, cell migration, and adhesion, and indirectly inhibit the phosphorylation of an intracellular mediator of TGF-ß signaling. This combined phenotypic profile identifies these compounds as a class of TGF-ß signaling inhibitors. Notably, heterotaxin analogs also possess highly desirable antitumor properties, inhibiting epithelial-mesenchymal transition, angiogenesis, and tumor cell proliferation in mammalian systems. Our results suggest that assessing multiple organ, tissue, cellular, and molecular parameters in a whole organism context is a valuable strategy for identifying the mechanism of action of bioactive compounds.


Subject(s)
Embryo, Nonmammalian/cytology , Embryo, Nonmammalian/drug effects , Phenotype , Pyridines/pharmacology , Signal Transduction/drug effects , Transforming Growth Factor beta/metabolism , Animals , Cell Line , Drug Evaluation, Preclinical , Embryo, Nonmammalian/abnormalities , Embryo, Nonmammalian/metabolism , Humans , Intracellular Space/drug effects , Intracellular Space/metabolism , Neovascularization, Physiologic/drug effects , Pyridines/chemistry , Stereoisomerism , Structure-Activity Relationship , Xenopus laevis
18.
Anat Rec (Hoboken) ; 293(6): 938-46, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20503388

ABSTRACT

Pre- and postnatal developmental studies of the lung have provided compelling evidence demonstrating multiple factors that orchestrate alveolar epithelial cell differentiation. The extent to which reactivation of certain developmental pathways in the adult might influence the course of differentiation of alveolar type 2 cells (AT2) into AT1 cells is not known. In this study, we examined selected members of the forkhead (Fox) family of transcription factors and the Wnt (wingless) family of signaling proteins for expression during human alveolar cell differentiation in vitro and determined their potential responses to sulfated components of extracellular matrix (ECM), like those shed from cell surfaces or found in basement membrane and modeled by heparin. Isolated adult human AT2 cells cultured over a 9-day period were used to define the temporal profile of expression of targeted factors during spontaneous differentiation to AT1-like cells. FoxA1 protein was upregulated at early to intermediate time points, where it was strongly elevated by heparin. Gene expression of wnt7A increased dramatically beginning on day 3 and was enhanced even further on days 7 and 9 by heparin, whereas protein expression appeared at days 7 and 9. These temporal changes of expression suggest that sulfated ECMs may act to enhance the increase in FoxA1 at the critical juncture when AT2 cells commence the differentiation process to AT1 cells, in addition to enhancing the increase in wnt7A when the AT1 cell phenotype stabilizes. Collectively, these factors may act to modulate differentiation in the adult human pulmonary alveolus.


Subject(s)
Heparin/physiology , Hepatocyte Nuclear Factor 3-alpha/biosynthesis , Pulmonary Alveoli/metabolism , Respiratory Mucosa/metabolism , Wnt Proteins/biosynthesis , Adult , Anticoagulants/physiology , Biomarkers/metabolism , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Line , Cell Separation , Cells, Cultured , Hepatocyte Nuclear Factor 3-alpha/genetics , Humans , Pulmonary Alveoli/cytology , Pulmonary Alveoli/drug effects , Respiratory Mucosa/cytology , Respiratory Mucosa/drug effects , Time Factors , Wnt Proteins/genetics , beta Catenin/biosynthesis , beta Catenin/genetics
19.
Am J Physiol Lung Cell Mol Physiol ; 293(5): L1314-20, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17766586

ABSTRACT

Fibroblast growth factors (FGFs) play critical roles in development, maintenance, and repair following injury or disease in the lung. Their activity is modulated by a variety of factors, including FGF-binding protein (FGF-BP; HBp-17) and N-deacetylase/N-sulfotransferase-1 (NDST-1). Functionally, FGF-BP shuttles FGFs from binding sites in ECMs to cell surfaces and enhances FGF binding and signaling, whereas NDST-1 adds sulfate groups to FGF coreceptor proteoglycans and modulates alveolar type II (ATII) cell maturation and differentiation. Since the sulfated nature of ECMs is a critical determinant of their relationship with FGFs, we predicted that ECMs and their sulfation would modulate the expression of FGF-BP and NDST-1. To examine this question, selected culture conditions of rat ATII cells were manipulated [with and without coculture with rat lung fibroblasts (RLFs)] by treatment with heparin or sodium chlorate (inhibitor of sulfation) for 24-96 h. In addition, ECMs biosynthesized by RLFs for up to 10 days before coculture were used as model intervening barriers to communication between alveolar cells and fibroblasts. FGF-BP expression was enhanced in ATII cells by coculture with RLF cells and least suppressed by desulfated heparin. NDST-1 expression in ATII cells was most sensitive to the amount of sulfation in medium and ECM and enhanced by fully sulfated heparin. Preformed ECM appears to supply factors that modify subsequent treatment effects. These results demonstrate a potentially important modulatory influence of sulfated ECMs and fibroblasts on FGF-BP and NDST-1 at the gene expression level.


Subject(s)
Carrier Proteins/metabolism , Extracellular Matrix/metabolism , Fibroblasts/metabolism , Heparin/pharmacology , Lung/metabolism , Pulmonary Alveoli/metabolism , Sulfotransferases/metabolism , Animals , Carrier Proteins/genetics , Cells, Cultured , Fibroblasts/cytology , Intercellular Signaling Peptides and Proteins , Lung/cytology , Pulmonary Alveoli/cytology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Reverse Transcriptase Polymerase Chain Reaction , Sulfotransferases/genetics
20.
Respir Res ; 8: 36, 2007 May 08.
Article in English | MEDLINE | ID: mdl-17488504

ABSTRACT

BACKGROUND: Heparin has been shown to modify fundamental biologic processes ranging from blood coagulation and cell proliferation to fibrogenesis and asthma. The goal of this study was to identify specific or broad biologic responses of the rat lung to intratracheal instillation of heparin by targeted proteomic analysis. METHODS: Rats were given either aerosolized 500 microg heparin in 250 microl saline or saline alone. Lungs were harvested at 0, 24, or 96 hours post-treatment and isolated proteins analyzed by two-dimensional gel electrophoresis. Proteins which increased and decreased significantly in treated groups above controls were then selected for identification by mass spectrometry. RESULTS: Although heparin treatments resulted in a general reduction in cytosolic protein expression, there were significant increases within members of discrete groups of proteins. At 24 hours, proteins which function in cytoskeletal organization and in calcium signaling were up-regulated between 2- and 27-fold above baseline and untreated controls. Increased proteins include annexins V and VI, septin 2, capping G protein, actin-related protein 3, moesin, RhoGDP dissociation inhibitor, and calcyclin. A group of proteins relating to immune response and tumor suppressor function were either up-regulated (tumor suppressor p30/hyaluronic acid binding protein-1, Parkinson disease protein 7, proteosome 28 subunit/interferon-gamma inducible protein, and proteosome subunit macropain alpha-1) or strongly down-regulated (transgelin). At 96 hours, most proteins that had increased at 24 hours remained elevated but to a much lesser degree. CONCLUSION: These cumulative observations demonstrate that whole lung heparin treatment results in significant up-regulation of selected groups of proteins, primarily those related to cytoskeletal reorganization and immune function, which may prove to be relevant biomarkers useful in analysis of lung exposures/treatments as well as in system biology studies.


Subject(s)
Anticoagulants/administration & dosage , Cytoskeleton/ultrastructure , Heparin/administration & dosage , Lung/drug effects , Lung/immunology , Proteome/drug effects , Administration, Inhalation , Animals , Cytoskeleton/drug effects , Gene Expression Regulation/drug effects , Lung/ultrastructure , Proteomics/methods , Rats , Rats, Inbred F344 , Reference Values
SELECTION OF CITATIONS
SEARCH DETAIL
...