title: Hyperoxia Induces Intracellular Acidification in Neonatal Mouse Lung Fibroblasts: Real-Time Investigation Using Plasmonically Enhanced Raman Spectroscopy.
abstract: It is important to understand the molecular mechanisms underlying oxygen toxicity, which contributes to multiple human disorders. The archetype model of oxygen toxicity is neonatal lung injury induced by hyperoxia exposure. Here, we utilized plasmonically enhanced Raman spectroscopy (PERS) in combination with fluorescence and proteomic analysis to provide comprehensive information on hyperoxia-induced biomolecular modifications in neonatal mouse lung fibroblasts (nMLFs). During this study, we made the novel observation that hyperoxia induces intracellular acidification in nMLF, which we probed in real-time using label-free PERS. We found that intracellular acidification induces conformational modifications in proteins followed by significant changes in Raman vibrations corresponding to aromatic amino acids such as phenylalanine and tryptophan as well as cysteine moieties. Hyperoxia-induced intracellular pH changes and subsequent modifications in protein expression and associated post-translational modifications within the cells were further validated by fluorescence and proteomic analysis. These new insights may help identifying unique oxidant stress-induced mechanisms in disease processes and may guide the development of more efficient therapeutic strategies.
authors.affiliation: Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States.
authors.forename: Sajanlal R
authors.initials: SR
authors.lastname: Panikkanvalappil
authors.affiliation: Department of Pediatrics, University of Alabama at Birmingham , Birmingham, Alabama 35233, United States.
authors.forename: Masheika
authors.initials: M
authors.lastname: James
authors.affiliation: Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Hira
authors.affiliation: Department of Surgery, University of Alabama at Birmingham , Birmingham, Alabama 35233, United States.
authors.forename: James
authors.initials: J
authors.lastname: Mobley
authors.affiliation: Department of Pediatrics, University of Alabama at Birmingham , Birmingham, Alabama 35233, United States.
authors.forename: Tamas
authors.initials: T
authors.lastname: Jilling
authors.affiliation: Department of Pediatrics, University of Alabama at Birmingham , Birmingham, Alabama 35233, United States.
authors.forename: Namasivayam
authors.initials: N
authors.lastname: Ambalavanan
authors.affiliation: Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology , Atlanta, Georgia 30332-0400, United States.|Department of Chemistry, King Abdulaziz University , Jeddah 21589, Saudi Arabia.
authors.forename: Mostafa A
authors.initials: MA
authors.lastname: El-Sayed
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003199:Computer Systems; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006046:Gold / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D018496:Hyperoxia / Q000378:metabolism* / Q000473:pathology; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D053768:Metal Nanoparticles / Q000737:chemistry; D051379:Mice; D018384:Oxidative Stress / Q000502:physiology; D010100:Oxygen / Q000633:toxicity*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D006046:Gold; D010100:Oxygen