title: Brief Isoflurane Anesthesia Produces Prominent Phosphoproteomic Changes in the Adult Mouse Hippocampus.
abstract: Anesthetics are widely used in medical practice and experimental research, yet the neurobiological basis governing their effects remains obscure. We have here used quantitative phosphoproteomics to investigate the protein phosphorylation changes produced by a 30 min isoflurane anesthesia in the adult mouse hippocampus. Altogether 318 phosphorylation alterations in total of 237 proteins between sham and isoflurane anesthesia were identified. Many of the hit proteins represent primary pharmacological targets of anesthetics. However, findings also enlighten the role of several other proteins-implicated in various biological processes including neuronal excitability, brain energy homeostasis, synaptic plasticity and transmission, and microtubule function-as putative (secondary) targets of anesthetics. In particular, isoflurane increases glycogen synthase kinase-3β (GSK3β) phosphorylation at the inhibitory Ser(9) residue and regulates the phosphorylation of multiple proteins downstream and upstream of this promiscuous kinase that regulate diverse biological functions. Along with confirmatory Western blot data for GSK3β and p44/42-MAPK (mitogen-activated protein kinase; reduced phosphorylation of the activation loop), we observed increased phosphorylation of microtubule-associated protein 2 (MAP2) on residues (Thr(1620,1623)) that have been shown to render its dissociation from microtubules and alterations in microtubule stability. We further demonstrate that diverse anesthetics (sevoflurane, urethane, ketamine) produce essentially similar phosphorylation changes on GSK3β, p44/p42-MAPK, and MAP2 as observed with isoflurane. Altogether our study demonstrates the potential of quantitative phosphoproteomics to study the mechanisms of anesthetics (and other drugs) in the mammalian brain and reveals how already a relatively brief anesthesia produces pronounced phosphorylation changes in multiple proteins in the central nervous system.
authors.forename: Samuel
authors.initials: S
authors.lastname: Kohtala
authors.forename: Wiebke
authors.initials: W
authors.lastname: Theilmann
authors.affiliation: Turku Centre for Biotechnology, University of Turku , FI-20014 Turku, Finland.
authors.forename: Tomi
authors.initials: T
authors.lastname: Suomi
authors.affiliation: Institute of Biomedicine, University of Helsinki , FI-00014 Helsinki, Finland.
authors.forename: Henna-Kaisa
authors.initials: HK
authors.lastname: Wigren
authors.affiliation: Institute of Biomedicine, University of Helsinki , FI-00014 Helsinki, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Porkka-Heiskanen
authors.affiliation: Turku Centre for Biotechnology, University of Turku , FI-20014 Turku, Finland.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Elo
authors.affiliation: Turku Centre for Biotechnology, University of Turku , FI-20014 Turku, Finland.
authors.forename: Anne
authors.initials: A
authors.lastname: Rokka
authors.forename: Tomi
authors.initials: T
authors.lastname: Rantamäki
mesh_terms: D000758:Anesthesia / Q000379:methods; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D006624:Hippocampus / Q000187:drug effects*; D007530:Isoflurane / Q000494:pharmacology*; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009473:Neuronal Plasticity / Q000187:drug effects*; D010766:Phosphorylation; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D008869:Microtubule-Associated Proteins; D000077149:Sevoflurane; D007530:Isoflurane; D020928:Mitogen-Activated Protein Kinases
keywords: Anesthesia; glycogen synthase kinase-3β; phosphopeptide enrichment; protein phosphorylation; quantitative phosphoproteomics