Integrins inhibit LPS-induced DNA strand breakage in cultured lung endothelial cells

1996 ◽  
Vol 270 (4) ◽  
pp. L689-L694 ◽  
Author(s):  
D. G. Hoyt ◽  
R. J. Mannix ◽  
M. E. Gerritsen ◽  
S. C. Watkins ◽  
J. S. Lazo ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Type Iv Collagen ◽  
Cell Types ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Dna Breakage ◽  
Type Iv ◽  
Strand Breakage ◽  
Lung Endothelial Cells ◽  
Dna Strand ◽  
Dna Strand Breakage

Collagen inhibits acute DNA strand breakage and apoptosis in sheep pulmonary artery endothelial cells (SPAEC) treated with lipopolysaccharide (LPS). Here we tested the ability of major basement membrane components, type IV collagen, laminin and fibronectin, and integrin ligands and anti-integrin antibodies to inhibit DNA breakage caused by LPS in SPAEC and BALB/c murine lung endothelial cells (MLEC). In situ labeling of DNA strand breaks with terminal deoxynucleotidyl transferase revealed similar DNA breakage in attached SPAEC and MLEC within 2 h after incubation with 1 microgram LPS/ml. Acute DNA strand breakage was reduced in cells plated on gelatin, type IV collagen, laminin, cellular fibronectin, or plasma fibronectin. DNA breakage was also suppressed by plating cells on surfaces coated with the integrin ligand hexapeptide, GRGDSP (40 micrograms/cm2), but not with GRADSP. LPS-induced DNA strand breakage was inhibited in MLEC plated on surfaces coated with antibodies to murine alpha 5-, beta 1, or beta 3-integrin subunits. Addition of anti-integrin antibodies, but not GRGDSP, to the medium above cell monolayers inhibited strand breakage. Despite similar acute DNA breakage, MLEC exhibited less detachment and apoptosis than SPAEC, consistent with a difference in the sensing or processing systems for apoptosis in these two cell types. These results demonstrate that extracellular matrices and integrin activation can inhibit the genotoxicity of LPS.

Integrin activation protects pulmonary endothelial cells from the genotoxic effects of bleomycin

1997 ◽  
Vol 273 (3) ◽  
pp. L612-L617 ◽  
Author(s):  
D. G. Hoyt ◽  
M. Rizzo ◽  
M. E. Gerritsen ◽  
B. R. Pitt ◽  
J. S. Lazo
Keyword(s):  
Endothelial Cells ◽  
Antitumor Antibiotic ◽  
Integrin Activation ◽  
Genotoxic Effects ◽  
Receptor Clustering ◽  
Dna Breakage ◽  
Pulmonary Endothelial Cells ◽  
Strand Breakage ◽  
Dna Strand ◽  
Dna Strand Breakage

Integrin activation promotes the survival of endothelial cells undergoing diverse forms of stress. Here we determined the ability of integrins to inhibit DNA strand breakage by bleomycin (BLM), a DNA-cleaving antitumor antibiotic that causes acute endothelial injury and subsequent pulmonary fibrosis. We found that BLM produced DNA breakage in cultured murine lung endothelial cells (MLEC) within 45 min of treatment as measured by DNA sedimentation and in situ labeling of 3'-OH by nick translation (ISNT). Two hours after the removal of BLM, we found a marked but incomplete reduction in DNA strand breakage as measured by ISNT, indicating that the damage was reversible. DNA sedimentation and ISNT demonstrated that strand breakage due to BLM was inhibited in MLEC cultured on fibronectin, and no evidence of breakage was found 2 h after removal of the drug in ISNT experiments. Gelatin, type IV collagen, laminin, and the integrin ligand peptide Gly-Arg-Gly-Asp-Ser-Pro, but not the inactive Gly-Arg-Ala-Asp-Ser-Pro peptide, also inhibited DNA strand breakage. Activation of integrins, either by coating surfaces with antibodies to alpha 5-, beta 1-, or beta 3-integrin subunits or by receptor clustering with the soluble antibodies, inhibited BLM-induced DNA breakage. Inhibition of BLM-induced DNA strand breakage by soluble beta 1-integrin antibody increased with increasing antibody concentration and duration of receptor clustering before BLM treatment. Thus integrin activation protects pulmonary endothelial cells from the genotoxic effects of BLM.

Collagen is a survival factor against LPS-induced apoptosis in cultured sheep pulmonary artery endothelial cells

1995 ◽  
Vol 269 (2) ◽  
pp. L171-L177 ◽  
Author(s):  
D. G. Hoyt ◽  
R. J. Mannix ◽  
J. M. Rusnak ◽  
B. R. Pitt ◽  
J. S. Lazo
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Artery ◽  
Dna Fragmentation ◽  
High Molecular Weight Dna ◽  
Strand Breaks ◽  
Strand Breakage ◽  
Dna Strand ◽  
Induced Apoptosis ◽  
Dna Strand Breakage

Lipopolysaccharide (LPS) causes direct pulmonary endothelial injury that can precipitate cell death. We investigated the ability of LPS to produce apoptosis in sheep pulmonary artery endothelial cells (SPAEC) grown in monolayer on plastic or collagen. When SPAEC were grown on plastic, LPS (100 ng/ml) caused internucleosomal DNA fragmentation (IDF) to 180- to 200-base pair ladders after 4 h. Higher-order chromatin damage, producing 50-kilobase DNA fragments, occurred within 2 h. Significant DNA strand breaks were seen in attached cells within 1 h incubation with > or = 1 ng LPS/ml, using in situ labeling by break extension (ISBE). DNA strand breakage in attached cells peaked after 2 h and remained elevated after 4 h. Detachment of SPAEC from the monolayer did not begin until 4 h. SPAEC cultured on collagen were protected from LPS-induced apoptosis; DNA damage measured by IDF, high-molecular-weight DNA fragmentation, and ISBE were suppressed. The protective effect of collagen was not due to inactivation of LPS. Thus LPS-induced apoptosis occurs in SPAEC after genotoxic damage and this process is suppressed by the extracellular matrix.

Implications of oxidative stress and inflammatory process in the cytotoxicity of capsaicin in human endothelial cells: lack of DNA strand breakage

Toxicology ◽  
2000 ◽  
Vol 147 (1) ◽  
pp. 41-49 ◽  
Author(s):  
François Richeux ◽  
Marta Cascante ◽  
Rachid Ennamany ◽  
Denise Sanchez ◽  
Ambaliou Sanni ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Endothelial Cells ◽  
Inflammatory Process ◽  
Human Endothelial Cells ◽  
Strand Breakage ◽  
Dna Strand ◽  
Dna Strand Breakage

scholarly journals Synthesis and DNA Strand Breakage Activity of Some 1,4-Diazepines

2003 ◽  
Vol 51 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Nobuko Mibu ◽  
Miho Yukawa ◽  
Nobuhiro Kashige ◽  
Yukiko Iwase ◽  
Yoshinobu Goto ◽  
...  
Keyword(s):  
Strand Breakage ◽  
Dna Strand ◽  
Dna Strand Breakage

Factors which affect DNA strand breakage in human leukocytes exposed to a tumor promoter, phorbol myristate acetate

1982 ◽  
Vol 60 (11) ◽  
pp. 1359-1366 ◽  
Author(s):  
H. C. Birnboim
Keyword(s):  
Hydrogen Peroxide ◽  
Dna Damage ◽  
Phorbol Myristate Acetate ◽  
Respiratory Burst ◽  
Superoxide Anion ◽  
Tumor Promoter ◽  
Myristate Acetate ◽  
Strand Breakage ◽  
Dna Strand ◽  
Dna Strand Breakage

We have recently reported that phorbol myristate acetate (PMA) induces extensive DNA strand break damage in human peripheral blood leukocytes. The mechanism of action involves superoxide anion and hydrogen peroxide which are generated by phagocytes during the "respiratory burst." In this report, we describe the effect of various inhibitors and scavengers on PMA-induced DNA damage. Azide and cyanide greatly increased the level of damage; sulfhydryl compounds (glutathione, cysteine, and cysteamine) and ascorbate markedly decreased the level of damage. Hydroxyl radical scavengers such as dimethyl sulfoxide (DMSO) and glycerol also decreased the level of damage but apparently did so by inhibiting the respiratory burst. Diethyldithiocarbamate (DDC) increased the level of DNA damage at low concentrations (<1 mM), but decreased DNA damage at ≥1 mM. The results are consistent with a mechanism involving superoxide anion and hydrogen peroxide, but the precise reaction (free radical or enzymatic) responsible for DNA strand breakage has not been determined. The PMA-stimulated phagocyte is an interesting model system for looking at "active oxygen" mediated DNA damage and factors which influence it.

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