In vivo treatment with diphenyl ditelluride induces neurodegeneration in striatum of young rats: Implications of MAPK and Akt pathways |
| |
Authors: | Luana HeimfarthSamanta Oliveira Loureiro,Má rcio Ferreira DutraClá udia Andrade,Letí cia PettenuzzoFá tima T. Costa Rodrigues Guma,Carlos Alberto Saraiva Gonç alvesJoã o Batista Teixeira da Rocha,Regina Pessoa-Pureur |
| |
Affiliation: | a Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazilb Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, RS Brazil |
| |
Abstract: | In the present report 15 day-old Wistar rats were injected with 0.3 μmol of diphenyl ditelluride (PhTe)2/kg body weight and parameters of neurodegeneration were analyzed in slices from striatum 6 days afterwards. We found hyperphosphorylation of intermediate filament (IF) proteins from astrocyte (glial fibrillary acidic protein—GFAP and vimentin) and from neuron (low-, medium- and high molecular weight neurofilament subunits: NF-L, NF-M and NF-H, respectively) and increased MAPK (Erk, JNK and p38MAPK) as well as PKA activities. The treatment induced reactive astrogliosis in the striatum, evidenced by increased GFAP and vimentin immunocontent as well as their mRNA overexpression. Also, (PhTe)2 significantly increased the propidium iodide (PI) positive cells in NeuN positive population without altering PI incorporation into GFAP positive cells, indicating that in vivo exposure to (PhTe)2 provoked neuronal damage. Immunohistochemistry showed a dramatic increase of GFAP staining characteristic of reactive astrogliosis. Moreover, increased caspase 3 in (PhTe)2 treated striatal slices suggested apoptotic cell death. (PhTe)2 exposure decreased Akt immunoreactivity, however phospho-GSK-3-β (Ser9) was unaltered, suggesting that this kinase is not directly implicated in the neurotoxicity of this compound. Therefore, the present results shed light into the mechanisms of (PhTe)2-induced neurodegeneration in rat striatum, evidencing a critical role for the MAPK and Akt signaling pathways and disruption of cytoskeletal homeostasis, which could be related with apoptotic neuronal death and astrogliosis. |
| |
Keywords: | (PhTe)2, diphenyl ditelluride IF, intermediate filament NF, neurofilament GFAP, glial fibrillary acidic protein NF-L, low molecular weight neurofilament subunit NF-M, medium molecular weight neurofilament subunit NF-H, high molecular weight neurofilament subunit MAPK, mitogen-activated protein kinase GSK3, glycogen synthase kinase 3 JNK1/3, c-jun N-terminus kinase 1 and 3 PKA, cAMP-dependent protein kinase PKCaM, Ca2+/calmodulin-dependent protein kinase PKC, Ca2+/diacylglycerol-dependent protein kinase |
本文献已被 ScienceDirect 等数据库收录! |
|