title: The Protective Effect of Bafilomycin A1 Against Cobalt Nanoparticle-Induced Cytotoxicity and Aseptic Inflammation in Macrophages In Vitro.
abstract: Co ions released due to corrosion of Co nanoparticles (CoNPs) in the lysosomes of macrophages may be a factor in the particle-induced cytotoxicity and aseptic inflammation accompanying metal-on-metal (MOM) hip prosthesis failure. Here, we show that CoNPs are easily dissolved under a low pH, simulating the acidic lysosomal environment. We then used bafilomycin A1 to change the pH inside the lysosome to inhibit intracellular corrosion of CoNPs and then investigated its protective effects against CoNP-induced cytotoxicity and aseptic inflammation on murine macrophage RAW264.7 cells. XTT {2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide} assays revealed that bafilomycin A1 can significantly decrease CoNP-induced cytotoxicity in RAW264.7 cells. Enzyme-linked immunosorbent assays showed that bafilomycin A1 can significantly decrease the subtoxic concentration of CoNP-induced levels of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6), but has no effect on anti-inflammatory cytokines (transforming growth factor-β and interleukin-10) in RAW264.7 cells. We studied the protective mechanism of bafilomycin A1 against CoNP-induced effects in RAW264.7 cells by measuring glutathione/oxidized glutathione (GSH/GSSG), superoxide dismutase, catalase, and glutathione peroxidase levels and employed scanning electron microscopy, transmission electron microscopy, and energy dispersive spectrometer assays to observe the ultrastructural cellular changes. The changes associated with apoptosis were assessed by examining the pAKT and cleaved caspase-3 levels using Western blotting. These data strongly suggested that bafilomycin A1 can potentially suppress CoNP-induced cytotoxicity and aseptic inflammation by inhibiting intracellular corrosion of CoNPs and that the reduction in Co ions released from CoNPs may play an important role in downregulating oxidative stress in RAW264.7 cells.
authors.affiliation: Department of Orthopedics, The First Affiliated Hospital of Soochow University, Shizi Street, Suzhou, 215006, Jiangsu Province, People's Republic of China.
authors.forename: Songhua
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Orthopedics, The Affiliated Hospital of Nantong University, 20 West Temple Road, Nantong, 226001, Jiangsu Province, People's Republic of China. fanliu1957@163.com.
authors.forename: Fan
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Orthopedics, The First Affiliated Hospital of Soochow University, Shizi Street, Suzhou, 215006, Jiangsu Province, People's Republic of China.
authors.forename: Zhaoxun
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Department of Orthopedics, The First Affiliated Hospital of Soochow University, Shizi Street, Suzhou, 215006, Jiangsu Province, People's Republic of China.
authors.forename: Huilin
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Orthopedics, The First People's Hospital of Taizhou City, Taizhou, Jiangsu Province, People's Republic of China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Jiang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D003035:Cobalt / Q000737:chemistry* / Q000494:pharmacology*; D007249:Inflammation / Q000139:chemically induced* / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D018942:Macrolides; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D053583:Interleukin-1beta; D015850:Interleukin-6; D018942:Macrolides; D014409:Tumor Necrosis Factor-alpha; D003035:Cobalt; C040929:bafilomycin A1
keywords: Cobalt nanoparticle; Inflammation; Intracellular solubilization; Lysosome; Toxicity