title: A proteomic study of plasma protein changes under extreme physical stress.
abstract: The Spartathlon race (brisk walking a distance of 246km in less than 36h) was employed as a model of severe physical stress to investigate proteomic alterations in the plasma of athletes at the start (Athens) and finish (Sparta) of the race, as well as 48h after the race (Post). The athletes' plasma was analyzed by 2D gel electrophoresis (2-DE) and the differentially expressed proteins were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS). The ProteoSeek™ Albumin/IgG removal kit and the ProteoMiner™ enrichment kit were utilized to detect medium- and low-abundance proteins, whose expression may be masked due to high-abundance proteins. Our results were confirmed by Western blot and biochemical analyses. Overall fifty-two proteins were differentially expressed between the starting point, the finishing line and two days after the end of the race. Of these, thirty proteins were involved in inflammation, while the rest concerned anti-oxidation, anti-coagulation and iron and vitamin D transport. These results indicate that prolonged physical stress affects circulating stress-related proteins, which might be employed as biomarkers of stress-related diseases.
  
  
  CONCLUSIONS
  The current study employed the Spartathlon, as a model of prolonged endurance exercise, to identify and isolate putative biomarkers of inflammation under extreme physical stress conditions. These protein quantitative variations may pave the way to exploration and understanding of stress-related physiological processes, the stress response itself and diseases whose onset appears to be linked to stress.
authors.affiliation: Proteomics Research Unit, Center of Basic Research II, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
authors.forename: Edily
authors.initials: E
authors.lastname: Balfoussia
authors.affiliation: Laboratory of Nutrition and Clinical Dietetics, "Harokopio" University, Athens, Greece.
authors.forename: Katerina
authors.initials: K
authors.lastname: Skenderi
authors.affiliation: Department of Internal Medicine, University of Peloponnesus, School of Nursing, Sparta, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Tsironi
authors.affiliation: Proteomics Research Unit, Center of Basic Research II, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
authors.forename: Athanasios K
authors.initials: AK
authors.lastname: Anagnostopoulos
authors.affiliation: First Department of Pediatrics, University of Athens Medical School, Athens, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Parthimos
authors.affiliation: Proteomics Research Unit, Center of Basic Research II, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
authors.forename: Kostantinos
authors.initials: K
authors.lastname: Vougas
authors.affiliation: Department of Clinical Biochemistry, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papassotiriou
authors.affiliation: Proteomics Research Unit, Center of Basic Research II, Biomedical Research Foundation of the Academy of Athens, Athens, Greece. Electronic address: gthtsangaris@bioacademy.gr.
authors.forename: George Th
authors.initials: GT
authors.lastname: Tsangaris
authors.affiliation: First Department of Pediatrics, University of Athens Medical School, Athens, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: George P
authors.initials: GP
authors.lastname: Chrousos
mesh_terms: D000328:Adult; D056352:Athletes; D001798:Blood Proteins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion / Q000502:physiology*; D040901:Proteomics; D012420:Running / Q000502:physiology*; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D001798:Blood Proteins
keywords: 2-DE; Endurance; Plasma; Proteomics; Spartathlon