Photobiomodulation reduces hippocampal apoptotic cell death and produces a Raman spectroscopic "signature"

David J Davies; Mohammed Hadis; Valentina Di Pietro; Giuseppe Lazzarino; Mario Forcione; Georgia Harris; Andrew R Stevens; Wai Cheong Soon; Pola Goldberg Oppenheimer; Michael Milward; Antonio Belli; William M Palin

doi:10.1371/journal.pone.0264533

Photobiomodulation reduces hippocampal apoptotic cell death and produces a Raman spectroscopic "signature"

PLoS One. 2022 Mar 3;17(3):e0264533. doi: 10.1371/journal.pone.0264533. eCollection 2022.

Authors

David J Davies^{1

2}, Mohammed Hadis³, Valentina Di Pietro¹, Giuseppe Lazzarino⁴, Mario Forcione^{1

2}, Georgia Harris⁵, Andrew R Stevens^{1

2}, Wai Cheong Soon¹, Pola Goldberg Oppenheimer⁵, Michael Milward³, Antonio Belli^{1

2}, William M Palin³

Affiliations

¹ Department of Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom.
² National Institute of Health Research Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham' Edgbaston, Birmingham, United Kingdom.
³ Photobiology Research Group, School of Dentistry, College of Medical and Dental Science, Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom.
⁴ Department of Chemical Sciences, Laboratory of Biochemistry, University of Catania, Catania, Italy.
⁵ Faculty of Chemical and Biological Engineering, University of Birmingham, Birmingham, United Kingdom.

Abstract

Apoptotic cell death within the brain represents a significant contributing factor to impaired post-traumatic tissue function and poor clinical outcome after traumatic brain injury. After irradiation with light in the wavelength range of 600-1200 nm (photobiomodulation), previous investigations have reported a reduction in apoptosis in various tissues. This study investigates the effect of 660 nm photobiomodulation on organotypic slice cultured hippocampal tissue of rats, examining the effect on apoptotic cell loss. Tissue optical Raman spectroscopic changes were evaluated. A significantly higher proportion of apoptotic cells 62.8±12.2% vs 48.6±13.7% (P<0.0001) per region were observed in the control group compared with the photobiomodulation group. After photobiomodulation, Raman spectroscopic observations demonstrated 1440/1660 cm-1 spectral shift. Photobiomodulation has the potential for therapeutic utility, reducing cell loss to apoptosis in injured neurological tissue, as demonstrated in this in vitro model. A clear Raman spectroscopic signal was observed after apparent optimal irradiation, potentially integrable into therapeutic light delivery apparatus for real-time dose metering.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Apoptosis
Brain
Brain Injuries, Traumatic* / metabolism
Hippocampus / metabolism
Low-Level Light Therapy* / methods
Rats
Spectrum Analysis, Raman

Grants and funding

DD received a grant from the Midland Neuroscience Teaching and Research Fund (University of Birmingham Grant Number 1001177) (https://mntrf.org.uk/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.