title: Macrophage-stimulating protein attenuates hydrogen peroxide-induced apoptosis in human renal HK-2 cells.
abstract: Macrophage-stimulating protein (MSP) and its receptor, recepteur d'origine nantais (RON), play an important role in cell proliferation and migration. We have investigated the role of MSP in hydrogen peroxide (H2O2)-induced renal tubular apoptosis. Human renal proximal tubular (HK-2) cells were incubated with H2O2 for 24h in the presence of different concentrations of MSP, and cell viability was measured by MTT assay. The protein expression of Bax, Bcl-2, caspase-3, mitogen-activated protein kinases (MAPKs), phosphatidylinositol-3-kinase (PI3K)/Akt, and nuclear factor-kappa B (NF-κB) was determined by semiquantitative immunoblotting. Apoptosis was assessed by flow cytometry analysis after HK-2 cells were stained with fluorescein isothiocyanate-conjugated annexin V protein and propidium iodide. H2O2 treatment decreased cell viability in HK-2 cells; this was counteracted by MSP pretreatment. H2O2 treatment induced an increased ratio of Bax/Bcl-2, cleaved caspase-3, and the number of condensed nuclei, which was also counteracted by MSP. Flow cytometry analysis showed H2O2-induced apoptosis, and its prevention by MSP treatment. Increased protein expression of phospho-p38 MAPK was attenuated by MSP, while phospho-extracellular signal-regulated kinase and c-Jun-N-terminal kinase were not affected. H2O2 induced NF-κB activation and IκB-α degradation, but the increased nuclear NF-κB activation was counteracted by MSP or by a p38 MAPK inhibitor. H2O2 treatment decreased expression of phospho-PI3K and phospho-Akt, which was reversed by MSP pretreatment. These findings suggest that MSP attenuates H2O2-induced apoptosis in HK-2 cells by modulating the p38 and NF-κB, as well as PI3K/Akt, signaling pathways.
authors.affiliation: Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea.
authors.forename: Ko Eun
authors.initials: KE
authors.lastname: Lee
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Chang Seong
authors.initials: CS
authors.lastname: Kim
authors.forename: Joon Seok
authors.initials: JS
authors.lastname: Choi
authors.forename: Eun Hui
authors.initials: EH
authors.lastname: Bae
authors.forename: Seong Kwon
authors.initials: SK
authors.lastname: Ma
authors.forename: Jung Sun
authors.initials: JS
authors.lastname: Park
authors.forename: Young Do
authors.initials: YD
authors.lastname: Jung
authors.forename: Suhn Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Jong Un
authors.initials: JU
authors.lastname: Lee
authors.forename: Soo Wan
authors.initials: SW
authors.lastname: Kim
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019610:Cytoprotection / Q000187:drug effects*; D005786:Gene Expression Regulation / Q000187:drug effects; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D007684:Kidney Tubules / Q000166:cytology*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D016328:NF-kappa B; D011518:Proto-Oncogene Proteins; D017382:Reactive Oxygen Species; C082332:macrophage stimulating protein; D017228:Hepatocyte Growth Factor; D006861:Hydrogen Peroxide; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases
keywords: Apoptosis; HK-2 cell; Hydrogen peroxide; Macrophage-stimulating protein; NF-κB