| Abstract: | Previous research demonstrated that rotenone (RT) induces neuronal injury partially by increasing intracellular Ca(2+) concentrations ([Ca(2+)]i), and inducing oxidative stress, leading to a neurodegenerative disorder. However, the mechanism of RT-induced injury remains elusive. Recent work revealed that Ca(2+) signaling is important for RT-induced senescence in human neuroblastoma SH-SY5Y cells. In the present study, we found that in SH-SY5Y cells, RT increased [Ca(2+)]i, senescence associated β-galactosidase activity, aggregation of lipofuscin, production of reactive oxygen species, G1/G0 cell cycle arrest, and activation of p53/p21 signaling proteins. In addition, RT decreased the expression of the signaling proteins for cell proliferation and survival, Cyclin-dependent kinase 2 (CDK2), cyclin D1, and Akt. Pretreatment of SH-SY5Y cells with isradipine, an L-type Ca(2+) channel blocker, or EGTA antagonized these effects of RT. These results suggested that application of isradipine might be a novel approach to prevent RT-induced neurodegenerative disorder such as Parkinson's disease.
Previous research demonstrated that rotenone (RT) induces neuronal injury partially by increasing intracellular Ca2+ concentrations ([Ca2+]i), and inducing oxidative stress, leading to a neurodegenerative disorder. However, the mechanism of RT-induced injury remains elusive. Recent work revealed that Ca2+ signaling is important for RT-induced senescence in human neuroblastoma SH-SY5Y cells. In the present study, we found that in SH-SY5Y cells, RT increased [Ca2+]i, senescence associated β-galactosidase activity, aggregation of lipofuscin, production of reactive oxygen species, G1/G0 cell cycle arrest, and activation of p53/p21signaling proteins. In addition, RT decreased the expression of the signaling proteins for cell proliferation and survival, Cyclin-dependent kinase 2 (CDK2), cyclin D1, and Akt. Pretreatment of SH-SY5Y cells with isradipine, an L-type Ca2+ channel blocker, or EGTA antagonized these effects of RT. These results suggested that application of isradipine might be a novel approach to prevent RT-induced neurodegenerative disorder such as Parkinson’s disease.
Abbreviations
[Ca2+]i, intracellular Ca2+ concentrations; CDK2, Cyclin-dependent kinase 2; DHP, dihydropyridine; DMEM, Dulbecco’s modified Eagle medium; DMSO, dimethylsulfoxide; EDTA, ethylenediaminetetraacetic acid; EGTA, ethylene glycol tetra-acetic acid; ELISA, enzyme-linked immunosorbent assay; FBS, fetal bovine serum; Lipo, lipofuscin; MPTP, 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine; MTT, 3-(4,5-dimethylthiahiazol-2-thiazolyl)-2,5-diphenyl-2H-tetraxolium bromide; NC, nitrocellulose filter; OCR, oxygen consumption rate; PD, Parkinson’s disease; PBS, phosphate-buffered saline; PBST, PBS with Tween 20; PI, propidiun iodide; PI3-kinase–Akt, phosphatidylinositol 3′-kinase/Akt; ROS, reactive oxygen species; RT, rotenone; SA-β-gal, senescence association β-galactosidase; SDS, sodium dodecyl sulfate; SNc DA, substantial nigra dopamine; VDCCs, voltage-dependent Ca2+ channels |
