Abstract
Photodynamic therapy (PDT) rapidly produces large amounts of reactive oxygen species (ROS) to induce death of photosensitized cells. As previously described in Chap. 2, excited photosensitizer (PS) molecules can either donate electrons (type 1) or energy (type 2) to ground-state oxygen to produce superoxide radicals (O2•−) or singlet oxygen (1O2). Each type of ROS has characteristic chemical reactivity and reacts with different types of chemical bonds present in biomolecules and, consequently, will lead to different types of cell damage. Once again, what determines the mechanism of cell death directly depends on both: the PS localization site within the cell and total extent of oxidative stress produced during therapy (i.e., light dosimetry and efficiency of ROS generation). To elucidate the mechanisms of photooxidative damage and the consequent biological effects, this chapter will cover the most relevant chemical reactions related to oxidative damage caused by 1O2 and free radicals.
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References
Halliwell B, Chirico S. Lipid peroxidation: its mechanism, measurement, and significance. Am J Clin Nutr. 1993;57(5 Suppl):715S–24; discussion 24S–25S.
Buettner GR. The pecking order of free radicals and antioxidants: lipid peroxidation, alpha-tocopherol, and ascorbate. Arch Biochem Biophys. 1993;300(2):535–43.
Halliwell B, Gutteridge JMC. Free radicals in biology and medicine. 5th ed. Oxford, UK: Oxford Press; 2015. 944 p.
Dumont E, Monari A. Understanding DNA under oxidative stress and sensitization: the role of molecular modeling. Front Chem. 2015;3:43.
Daly MJ, Gaidamakova EK, Matrosova VY, Vasilenko A, Zhai M, Leapman RD, et al. Protein oxidation implicated as the primary determinant of bacterial radioresistance. PLoS Biol. 2007;5(4):e92.
Davies MJ. Protein oxidation and peroxidation. Biochem J. 2016;473(7):805–25.
Kearns DR. Physical and chemical properties of singlet molecular oxygen. Chem Rev. 1971;71(4):32.
Bland J. Biochemical effects of excited state molecular oxygen. J Chem Educ. 1976;53(5):5.
Dalle-Donne I, Rossi R, Giustarini D, Milzani A, Colombo R. Protein carbonyl groups as biomarkers of oxidative stress. Clin Chim Acta. 2003;329(1–2):23–38.
Duan J, Kasper DL. Oxidative depolymerization of polysaccharides by reactive oxygen/nitrogen species. Glycobiology. 2011;21(4):401–9.
Agnez-Lima LF, Melo JT, Silva AE, Oliveira AH, Timoteo AR, Lima-Bessa KM, et al. DNA damage by singlet oxygen and cellular protective mechanisms. Mutat Res. 2012;751(1):15–28.
Acknowledgments
Mr. Hamblin was supported by US NIH grant R01AI050875.
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Sabino, C.P., Hamblin, M.R. (2016). Molecular Damage. In: Sellera, F., Nascimento, C., Ribeiro, M. (eds) Photodynamic Therapy in Veterinary Medicine: From Basics to Clinical Practice. Springer, Cham. https://doi.org/10.1007/978-3-319-45007-0_4
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DOI: https://doi.org/10.1007/978-3-319-45007-0_4
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