title: Effect of therapeutic concentration of lithium on live HEK293 cells; increase of Na+/K+-ATPase, change of overall protein composition and alteration of surface layer of plasma membrane.
abstract: The effect of long-term exposure of live cells to lithium cations (Li) was studied in HEK293 cells cultivated in the presence of 1mM LiCl for 7 or 21days. The alteration of Na+/K+-ATPase level, protein composition and biophysical state of plasma membrane was determined with the aim to characterize the physiological state of Li-treated cells.
  
  
  
  Na+/K+-ATPase level was determined by [3H]ouabain binding and immunoblot assays. Overall protein composition was determined by 2D electrophoresis followed by proteomic analysis by MALDI-TOF MS/MS and LFQ. Li interaction with plasma membrane was characterized by fluorescent probes DPH, TMA-DPH and Laurdan.
  
  
  
  Na+/K+-ATPase was increased in plasma membranes isolated from cells exposed to Li. Identification of Li-altered proteins by 2D electrophoresis, MALDI-TOF MS/MS and LFQ suggests a change of energy metabolism in mitochondria and cytosol and alteration of cell homeostasis of calcium. Measurement of Laurdan generalized polarization indicated a significant alteration of surface layer of isolated plasma membranes prepared from both types of Li-treated cells.
  
  
  
  Prolonged exposure of HEK293 cells to 1mM LiCl results in up-regulation of Na+/K+-ATPase expression, reorganization of overall cellular metabolism and alteration of the surface layer/polar head-group region of isolated plasma membranes.
  
  
  
  Our findings demonstrate adaptation of live HEK293 cell metabolism to prolonged exposure to therapeutic concentration of Li manifested as up-regulation of Na+/K+-ATPase expression, alteration of protein composition and change of the surface layer of plasma membrane.
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic. Electronic address: miroslava.vosahlikova@fgu.cas.cz.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Vosahlikova
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Ujcikova
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Chernyavskiy
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Brejchova
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Roubalova
authors.affiliation: Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada; National Institute of Mental Health, Klecany, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Alda
authors.affiliation: Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Svoboda
mesh_terms: D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism*; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004734:Energy Metabolism / Q000187:drug effects; D057809:HEK293 Cells; D006801:Humans; D008094:Lithium / Q000494:pharmacology*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D040901:Proteomics / Q000379:methods; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D010042:Ouabain; D008094:Lithium; D000254:Sodium-Potassium-Exchanging ATPase
keywords: HEK293 cells; Lithium; Membrane biophysics; Na(+)/K(+)-ATPase; Proteomic analysis