title: Label-free monitoring of tissue biochemistry following traumatic brain injury using Raman spectroscopy.
abstract: Traumatic brain injury (TBI) constitutes a major cause of death and long-term disability. At present, we lack methods to non-invasively track tissue biochemistry and hence select appropriate interventions for patients. We hypothesized that detailed label-free vibrational chemical analysis of focal TBI could provide such information. We assessed the early spatial and temporal changes in tissue biochemistry that are associated with brain injury in mice. Numerous differences were observed in the spectra of the contusion core and pericontusional tissue between 2 and 7 days. For example, a strong signal from haem was seen in the contusion core at 2 days due to haemorrhage, which subsequently resolved. More importantly, elevated cholesterol levels were demonstrated by 7 days, which may be a marker of important cell repair processes. Principal component analysis revealed an early 'acute' component dominated by haemorrhage and a delayed component reflecting changes in protein and lipid composition. Notably we demonstrated changes in Raman signature with time even in the contralateral hemisphere when compared to sham control mice. Raman spectroscopy therefore shows promise as a probe that is sensitive to important pathobiological processes in TBI and could be applied in future both in the experimental setting, as well as in the clinic.
authors.affiliation: Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK. js2238@cam.ac.uk laura.bollepalli@cruk.cam.ac.uk seb53@cam.ac.uk and Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK.
authors.forename: Jakub Maciej
authors.initials: JM
authors.lastname: Surmacki
authors.affiliation: Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK. js2238@cam.ac.uk laura.bollepalli@cruk.cam.ac.uk seb53@cam.ac.uk and Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Ansel-Bollepalli
authors.affiliation: Department of Neuroscience, IRCCS - Istituto de Ricerche Farmacologiche Mario Negri, Via G. La Masa 19, 20156 Milano, Italy. francesca.pischiutta@marionegri.it elisa.zanier@marionegri.it.
authors.forename: Francesca
authors.initials: F
authors.lastname: Pischiutta
authors.affiliation: Department of Neuroscience, IRCCS - Istituto de Ricerche Farmacologiche Mario Negri, Via G. La Masa 19, 20156 Milano, Italy. francesca.pischiutta@marionegri.it elisa.zanier@marionegri.it.
authors.forename: Elisa R
authors.initials: ER
authors.lastname: Zanier
authors.affiliation: Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK. ae105@cam.ac.uk.
authors.forename: Ari
authors.identifier: 0000-0001-8350-8093
authors.initials: A
authors.lastname: Ercole
authors.affiliation: Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK. js2238@cam.ac.uk laura.bollepalli@cruk.cam.ac.uk seb53@cam.ac.uk and Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK.
authors.forename: Sarah Elizabeth
authors.identifier: 0000-0003-0371-8635
authors.initials: SE
authors.lastname: Bohndiek
mesh_terms: D000818:Animals; D000070642:Brain Injuries, Traumatic / Q000473:pathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D025341:Principal Component Analysis; D013059:Spectrum Analysis, Raman / Q000379:methods*