Identifying Specific Subcellular Organelle Damage by Photosensitized Oxidations.

Identifying Specific Subcellular Organelle Damage by Photosensitized Oxidations. Yale J Biol Med. 2019 Sep;92(3):413-422 Authors: Tsubone TM, Martins WK, Baptista MS Abstract The search for conditions that maximize the outcome of Photodynamic Therapy (PDT) continues. Recent data indicate that PDT-induced cell death depends more on the specific intracellular location of the photosensitizer (PS) than on any other parameter. Indeed, knowledge of the PS intracellular location allows the establishment of clear relationships between the mechanism of cell death and the PDT efficacy. In order to determine the intracellular localization sites of a given PS, classical co-localization protocols, which are based in the comparison of the emissive profiles of organelle-specific probes to those of the PS, are usually performed. Since PSs are usually not efficient fluorophores, co-localization protocols require relatively high PS concentrations (micromolar range), distorting the whole proposal of the experiment, as high PS concentration means accumulation in many low-affinity sites. To overcome this difficulty, herein we describe a method that identifies PS intracellular localization by recognizing and quantifying the photodamage at intracellular organelles. We propose that irradiation protocols and characterization of major sites of photodamage results from many cycles of photosensitized oxidations, furnishing an integrated picture of the PS locati...
Source: The Yale Journal of Biology and Medicine - Category: Universities & Medical Training Tags: Yale J Biol Med Source Type: research