title: Hypobaric hypoxia-mediated protein expression in plasma of susceptible & tolerant rats.
abstract: OBJECTIVE
  Low availability of oxygen at high altitudes has a great impact on the human life processes. There is a widespread interest and need to find out protein(s) that are possibly involved in mediating tolerance to hypobaric hypoxia. We undertook this study to identify and characterize protein expression in plasma of hypoxia susceptible and tolerant rats.
  
  
  METHODS
  Male albino Sprague Dawley rats were segregated into susceptible and tolerant groups on the basis of their gasping time when exposed to simulated hypobaric hypoxia of 32,000 ft (9,754 m) at 32°C. Comparative proteome profiling of blood plasma of hypoxia susceptible and tolerant individuals was performed using 2-dimentional (2-D) gel electrophoresis.
  
  
  RESULTS
  Three proteins with higher expression levels were selected separately from tolerant and susceptible samples. Characterization of these proteins from tolerant sample using MALDI-TOF/TOF and MASCOT search indicated their homology with two different super-families viz. NADB-Rossmann superfamily (Rab GDP dissociation inhibitor β) and Transferrin superfamily (two Serotransferrins), having potential role in imparting tolerance against hypoxia. Three high level upregulated proteins were characterized from blood plasma of hypoxia susceptible animals showing similarity with threonine tRNA ligase (mitochondrial), carbohydrate sulphotransferase 7 and aspartate tRNA ligase (cytoplasmic) that play a role in ATP binding, carbohydrate metabolism and protein biosynthesis, respectively.
  
  
  CONCLUSIONS
  Our results indicated that rats segregated into hypoxia sensitive and tolerant based on their gasping time showed differential expression of proteins in blood plasma. Characterization of these differentially expressed proteins will lead to better understanding of molecular responses occurring during hypoxia and subsequently development of biomarkers for categorization of hypoxia susceptible and tolerant individuals.
authors.forename: Santosh
authors.initials: S
authors.lastname: Kumar
authors.forename: Priyanka
authors.initials: P
authors.lastname: Sharma
authors.forename: Anju
authors.initials: A
authors.lastname: Bansal
authors.forename: Prakash C
authors.initials: PC
authors.lastname: Sharma
authors.affiliation: University School of Biotechnology, Guru Gobind Singh Indraprastha University, New Delhi, India.
authors.forename: Kamal K
authors.initials: KK
authors.lastname: Aggarwal
mesh_terms: D000531:Altitude; D000818:Animals; D015415:Biomarkers / Q000097:blood*; D001798:Blood Proteins / Q000096:biosynthesis*; D005786:Gene Expression Regulation; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000235:genetics* / Q000473:pathology; D040901:Proteomics; D051381:Rats
chemical_list: D015415:Biomarkers; D001798:Blood Proteins