Nonenzymatic conversion of ADP-ribosylated arginines to ornithine alters the biological activities of human neutrophil peptide-1.
Activated neutrophils, recruited to the airway of diseased lung, release human neutrophil peptides (HNP1-4) that are cytotoxic to airway cells as well as microbes. Airway epithelial cells express arginine-specific ADP ribosyltransferase (ART)-1, a GPI-anchored ART that transfers ADP-ribose from NAD to arginines 14 and 24 of HNP-1. We previously reported that ADP-ribosyl-arginine is converted nonenzymatically to ornithine and that ADP-ribosylated HNP-1 and ADP-ribosyl-HNP-(ornithine) were isolated from bronchoalveolar lavage fluid of a patient with idiopathic pulmonary fibrosis, indicating that these reactions occur in vivo. To determine effects of HNP-ornithine on the airway, three analogs of HNP-1, HNP-(R14orn), HNP-(R24orn), and HNP-(R14,24orn), were tested for their activity against Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus; their cytotoxic effects on A549, NCI-H441, small airway epithelial-like cells, and normal human lung fibroblasts; and their ability to stimulate IL-8 and TGF-β1 release from A549 cells, and to serve as ART1 substrates. HNP and the three analogs had similar effects on IL-8 and TGF-β1 release from A549 cells and were all cytotoxic for small airway epithelial cells, NCI-H441, and normal human lung fibroblasts. HNP-(R14,24orn), when compared with HNP-1 and HNP-1 with a single ornithine substitution for arginine 14 or 24, exhibited reduced cytotoxicity, but it enhanced proliferation of A549 cells and had antibacterial activity. Thus, arginines 14 and 24, which can be ADP ribosylated by ART1, are critical to the regulation of the cytotoxic and antibacterial effects of HNP-1. The HNP analog, HNP-(R14,24orn), lacks the epithelial cell cytotoxicity of HNP-1, but partially retains its antibacterial activity and thus may have clinical applications in airway disease.
Cardiovascular and Pulmonary Branch, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892;
Linda A
LA
Stevens
Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI 53226;
Joseph T
JT
Barbieri
Biophysics Core Facility, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892;
Grzegorz
G
Piszczek
Cardiovascular and Pulmonary Branch, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892;
Amy N
AN
Otuonye
Laboratory of Biochemistry, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; and.
Rodney L
RL
Levine
Office of Biostatistics Research, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
Gang
G
Zheng
Cardiovascular and Pulmonary Branch, National, Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892; mossj@nhlbi.nih.gov.
Joel
J
Moss
D036002:ADP Ribose Transferases / Q000378:metabolism*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001120:Arginine / Q000378:metabolism*; D002460:Cell Line; D045744:Cell Line, Tumor; D005347:Fibroblasts / Q000187:drug effects; D058851:GPI-Linked Proteins / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis; D051379:Mice; D009504:Neutrophils / Q000378:metabolism*; D009952:Ornithine / Q000378:metabolism*; D051381:Rats; D053773:Transforming Growth Factor beta1 / Q000096:biosynthesis; D023084:alpha-Defensins / Q000378:metabolism* / Q000494:pharmacology / Q000633:toxicity
D000900:Anti-Bacterial Agents; D058851:GPI-Linked Proteins; D016209:Interleukin-8; D053773:Transforming Growth Factor beta1; D023084:alpha-Defensins; C406413:human neutrophil peptide 1; D001120:Arginine; D009952:Ornithine; D036002:ADP Ribose Transferases; C449301:ART1 protein, human