Connexin43 Hemichannels Contribute to Cadmium-Induced Oxidative Stress and Cell Injury
Author(s)
Fang, Xin
Huang, Tao
Zhu, Ying
Yan, Qiaojing
Chi, Yuan
X. Jiang, Jean
Wang, Peiyu
Matsue, Hiroyuki
Kitamura, Masanori
Yao, Jian
Griffith University Author(s)
Year published
2011
Metadata
Show full item recordAbstract
We investigated the potential involvement of connexin hemichannels in cadmium ions (Cd2+)-elicited cell injury. Transfection of LLC-PK1 cells with a wild-type connexin43 (Cx43) sensitized them to Cd2+-elicited cell injury. The cell susceptibility to Cd2+ was increased by depletion of glutathione (GSH) with DL-buthionine-[S,R]- sulfoximine, and decreased by N-acetyl-cysteine or glutathione reduced ethyl ester. Fibroblasts derived from Cx43 wild-type (Cx43+/+) and knockout (Cx43-/-) fetal littermates displayed different susceptibility to Cd2+. Cd2+ induced a higher concentration of reactive oxygen species, a stronger ...
View more >We investigated the potential involvement of connexin hemichannels in cadmium ions (Cd2+)-elicited cell injury. Transfection of LLC-PK1 cells with a wild-type connexin43 (Cx43) sensitized them to Cd2+-elicited cell injury. The cell susceptibility to Cd2+ was increased by depletion of glutathione (GSH) with DL-buthionine-[S,R]- sulfoximine, and decreased by N-acetyl-cysteine or glutathione reduced ethyl ester. Fibroblasts derived from Cx43 wild-type (Cx43+/+) and knockout (Cx43-/-) fetal littermates displayed different susceptibility to Cd2+. Cd2+ induced a higher concentration of reactive oxygen species, a stronger activation c-Jun N-terminal kinase, and significantly more severe cell injury in Cx43+/+ fibroblasts, as compared with Cx43-/- fibroblasts. Cd2+ caused a reduction in intracellular GSH, whereas it elevated extracellular GSH. This effect of Cd2+ was more dramatic in Cx43+/+ than Cx43-/- fibroblasts. Treatment of Cx43+/+ fibroblasts with Cd2+ caused a Cx43 hemichannel-dependent influx of Lucifer Yellow and efflux of ATP. Collectively, our study demonstrates that Cx43 sensitizes cells to Cd2+-initiated cytotoxicity, possibly through hemichannel-mediated effects on intracellular oxidative status.
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View more >We investigated the potential involvement of connexin hemichannels in cadmium ions (Cd2+)-elicited cell injury. Transfection of LLC-PK1 cells with a wild-type connexin43 (Cx43) sensitized them to Cd2+-elicited cell injury. The cell susceptibility to Cd2+ was increased by depletion of glutathione (GSH) with DL-buthionine-[S,R]- sulfoximine, and decreased by N-acetyl-cysteine or glutathione reduced ethyl ester. Fibroblasts derived from Cx43 wild-type (Cx43+/+) and knockout (Cx43-/-) fetal littermates displayed different susceptibility to Cd2+. Cd2+ induced a higher concentration of reactive oxygen species, a stronger activation c-Jun N-terminal kinase, and significantly more severe cell injury in Cx43+/+ fibroblasts, as compared with Cx43-/- fibroblasts. Cd2+ caused a reduction in intracellular GSH, whereas it elevated extracellular GSH. This effect of Cd2+ was more dramatic in Cx43+/+ than Cx43-/- fibroblasts. Treatment of Cx43+/+ fibroblasts with Cd2+ caused a Cx43 hemichannel-dependent influx of Lucifer Yellow and efflux of ATP. Collectively, our study demonstrates that Cx43 sensitizes cells to Cd2+-initiated cytotoxicity, possibly through hemichannel-mediated effects on intracellular oxidative status.
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Journal Title
Antioxidants & Redox Signaling
Volume
14
Issue
12
Subject
Biochemistry and Cell Biology
Medical Biochemistry and Metabolomics
Pharmacology and Pharmaceutical Sciences