title: Apoptosis induced by lipid-associated membrane proteins from Mycoplasma hyopneumoniae in a porcine lung epithelial cell line with the involvement of caspase 3 and the MAPK pathway.
abstract: Lipid-associated membrane proteins (LAMPs) are important in the pathogenicity of the Mycoplasma genus of bacteria. We investigated whether Mycoplasma hyopneumoniae LAMPs have pathogenic potential by inducing apoptosis in a St. Jude porcine lung epithelial cell line (SJPL). LAMPs from a pathogenic strain of M. hyopneumoniae (strain 232) were used in the research. Our investigation made use of diamidino-phenylindole (DAPI) and acridine orange/ethidium bromide (AO/EB) staining, terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) analysis, and Annexin-V-propidium iodide staining. After LAMP treatment for 24 h, typical changes were induced, chromosomes were concentrated, apoptotic bodies were observed, the 3'-OH groups of cleaved genomes were exposed, and the percentage of apoptotic cells reached 36.5 ± 11.66%. Caspase 3 and caspase 8 were activated and cytochrome c (cyt c) was released from the mitochondria into the cytoplasm; poly ADP ribose polymerase (PARP) was digested into two fragments; p38 mitogen-activated protein kinase (MAPK) was phosphorylated; and the expression of pro-apoptosis protein Bax increased while the anti-apoptosis protein Bcl-2 decreased. LAMPs also stimulated SJPL cells to produce nitric oxide (NO) and superoxide. This study demonstrated that LAMPs from M. hyopneumoniae can induce apoptosis in SJPL cells through the activation of caspase 3, caspase 8, cyt c, Bax, and p38 MAPK, thereby contributing to our understanding of the pathogenesis of M. hyopneumoniae, which should improve the treatment of M. hyopneumoniae infections.
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: B
authors.initials: B
authors.lastname: Ni
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: F F
authors.initials: FF
authors.lastname: Bai
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: M J
authors.initials: MJ
authors.lastname: Liu
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: Z X
authors.initials: ZX
authors.lastname: Feng
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: Q Y
authors.initials: QY
authors.lastname: Xiong
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: L Z
authors.initials: LZ
authors.lastname: Hua
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-Products, Nanjing, China.
authors.forename: G Q
authors.initials: GQ
authors.lastname: Shao
mesh_terms: D000818:Animals; D017209:Apoptosis; D001426:Bacterial Proteins / Q000494:pharmacology*; D053148:Caspase 3 / Q000378:metabolism*; D053181:Caspase 8 / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004847:Epithelial Cells / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D020287:In Situ Nick-End Labeling; D008168:Lung / Q000166:cytology*; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008954:Models, Biological; D045705:Mycoplasma hyopneumoniae / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D034421:Sus scrofa; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D051028:bcl-2-Associated X Protein; D013481:Superoxides; D009569:Nitric Oxide; D045304:Cytochromes c; D011065:Poly(ADP-ribose) Polymerases; D048051:p38 Mitogen-Activated Protein Kinases; D053148:Caspase 3; D053181:Caspase 8