Tag: migration

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HB-EGF-Promoted Airway Smooth Muscle Cells and Their Progenitor Migration Contribute to Airway Smooth Muscle Remodeling in Asthmatic Mouse.

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HB-EGF-Promoted Airway Smooth Muscle Cells and Their Progenitor Migration Contribute to Airway Smooth Muscle Remodeling in Asthmatic Mouse.

J Immunol. 2016 Jan 29;

Authors: Wang Q, Li H, Yao Y, Lu G, Wang Y, Xia D, Zhou J

Abstract
The airway smooth muscle (ASM) cells’ proliferation, migration, and their progenitor’s migration are currently regarded as causative factors for ASM remodeling in asthma. Heparin-binding epidermal growth factor (HB-EGF), a potent mitogen and chemotactic factor, could promote ASM cell proliferation through MAPK pathways. In this study, we obtained primary ASM cells and their progenitors from C57BL/6 mice and went on to explore the role of HB-EGF in these cells migration and the underlying mechanisms. We found that recombinant HB-EGF (rHB-EGF) intratracheal instillation accelerated ASM layer thickening in an OVA-induced asthmatic mouse. Modified Boyden chamber assay revealed that rHB-EGF facilitate ASM cell migration in a dose-dependent manner and ASM cells from asthmatic mice had a greater migration ability than that from normal counterparts. rHB-EGF could stimulate the phosphorylation of ERK1/2 and p38 in ASM cells but further migration assay showed that only epidermal growth factor receptor inhibitor (AG1478) or p38 inhibitor (SB203580), but not ERK1/2 inhibitor (PD98059), could inhibit rHB-EGF-mediated ASM cells migration. Actin cytoskeleton experiments exhibited that rHB-EGF could cause actin stress fibers disassembly and focal adhesions formation of ASM cells through the activation of p38. Finally, airway instillation of rHB-EGF promoted the recruitment of bone marrow-derived smooth muscle progenitor cells, which were transferred via caudal vein, migrating into the airway from the circulation. These observations demonstrated that ASM remodeling in asthma might have resulted from HB-EGF-mediated ASM cells and their progenitor cells migration, via p38 MAPK-dependent actin cytoskeleton remodeling.

PMID: 26826248 [PubMed – as supplied by publisher]

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Apigenin inhibits TGF-?1-induced proliferation and migration of airway smooth muscle cells.

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Apigenin inhibits TGF-?1-induced proliferation and migration of airway smooth muscle cells.

Int J Clin Exp Pathol. 2015;8(10):12557-63

Authors: Li LH, Lu B, Wu HK, Zhang H, Yao FF

Abstract
It is well known that the proliferation and migration of ASM cells (ASMCs) plays an important role in the pathogenesis of airway remodeling in asthma. Previous studies reported that apigenin can inhibit airway remodeling in a mouse asthma model. However, its effects on the proliferation and migration of ASMCs in asthma remain unknown. Therefore, the aim of our present study was to investigate the effects of apigenin on ASMC proliferation and migration, and explore the possible molecular mechanism. We found that apigenin inhibited transforming growth factor-?1 (TGF-?1)-induced ASMC proliferation. The cell cycle was blocked at G1/S-interphase by apigenin. It also suppressed TGF-?1-induced ASMCs migration. Furthermore, apigenin inhibited TGF-?1-induced Smad 2 and Smad 3 phosphorylation in ASMCs. Taken together, these results suggested that apigenin inhibited the proliferation and migration of TGF-?1-stimulated ASMCs by inhibiting Smad signaling pathway. These data might provide useful information for treating asthma and show that apigenin has potential for attenuating airway remodeling.

PMID: 26722444 [PubMed – in process]

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Toluene diisocyanate emission to air and migration to a surface from a flexible polyurethane foam.

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Toluene diisocyanate emission to air and migration to a surface from a flexible polyurethane foam.

Ann Occup Hyg. 2013 Jun;57(5):650-61

Authors: Vangronsveld E, Berckmans S, Spence M

Abstract
Flexible polyurethane foam (FPF) is produced from the reaction of toluene diisocyanate (TDI) and polyols. Because of the potential for respiratory sensitization following exposure to TDI, concerns have been raised about potential consumer exposure to TDI from residual ‘free TDI’ in FPF products. Limited and conflicting results exist in the literature concerning the presence of unreacted TDI remaining in FPF as determined by various solvent extraction and analysis techniques. Because residual TDI results are most often intended for application in assessment of potential human exposure to TDI from FPF products, testing techniques that more accurately simulated human contact with foam were designed. To represent inhalation exposure to TDI from polyurethane foam, a test that measured the emission of TDI to air was conducted. For simulation of human dermal exposure to TDI from polyurethane foam, a migration test technique was designed. Emission of TDI to air was determined for a representative FPF using three different emission test cells. Two were commercially available cells that employ air flow over the surface of the foam [the Field and Laboratory Emission Cell (FLEC®) and the Micro-Chamber/Thermal Extraction™ cell]. The third emission test cell was of a custom design and features air flow through the foam sample rather than over the foam surface. Emitted TDI in the air of the test cells was trapped using glass fiber filters coated with 1-(2-methoxyphenyl)-piperazine (MP), a commonly used derivatizing agent for diisocyanates. The filters were subsequently desorbed and analyzed by liquid chromatography/mass spectrometry. Measurement of TDI migration from representative foam was accomplished by placing glass fiber filters coated with MP on the outer surfaces of a foam disk and then compressing the filters against the disk using a clamping apparatus for periods of 8 and 24 h. The sample filters were subsequently desorbed and analyzed in the same manner as for the emission tests. Although the foam tested had detectable levels of solvent-extractable TDI (56ng TDI g(-1) foam for the foam used in emissions tests; 240-2800ng TDI g(-1) foam for the foam used in migration tests), no TDI was detected in any of the emission or migration tests. Method detection limits (MDLs) for the emissions tests ranged from 0.03 to 0.5ng TDI g(-1) foam (0.002-0.04ng TDI cm(-2) of foam surface), whereas those for the migration tests were 0.73ng TDI g(-1) foam (0.16ng TDI cm(-2) of foam surface). Of the three emission test methods used, the FLEC® had the lowest relative MDLs (by a factor of 3-10) by virtue of its high chamber loading factor. In addition, the FLEC® cell offers well-established conformity with emission testing standard methods.

PMID: 23680588 [PubMed – indexed for MEDLINE]

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