title: Impact of photosensitizers activation on intracellular trafficking and viscosity.
abstract: The intracellular microenvironment is essential for the efficiency of photo-induced therapies, as short-lived reactive oxygen species generated must diffuse through their intracellular surrounding medium to reach their cellular target. Here, by combining measurements of local cytoplasmic dissipation and active trafficking, we found that photosensitizers activation induced small changes in surrounding viscosity but a massive decrease in diffusion. These effects are the signature of a return to thermodynamic equilibrium of the system after photo-activation and correlated with depolymerization of the microtubule network, as shown in a reconstituted system. These mechanical measurements were performed with two intracellular photosensitizing chlorins having similar quantum yield of singlet oxygen production but different intracellular localizations (cytoplasmic for mTHPC, endosomal for TPCS2a). These two agents demonstrated different intracellular impact.
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), CNRS and Université Paris Diderot, Paris, France.
authors.forename: Kelly
authors.initials: K
authors.lastname: Aubertin
authors.affiliation: Laboratoire Jean Perrin-CNRS, Université Pierre et Marie Curie, Paris 6, Paris, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Bonneau
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), CNRS and Université Paris Diderot, Paris, France.
authors.forename: Amanda K A
authors.initials: AK
authors.lastname: Silva
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), CNRS and Université Paris Diderot, Paris, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Bacri
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), CNRS and Université Paris Diderot, Paris, France.
authors.forename: François
authors.initials: F
authors.lastname: Gallet
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), CNRS and Université Paris Diderot, Paris, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Wilhelm
mesh_terms: D001693:Biological Transport, Active / Q000187:drug effects; D045744:Cell Line, Tumor; D003593:Cytoplasm / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D006801:Humans; D017319:Photosensitizing Agents / Q000494:pharmacology*; D014783:Viscosity / Q000187:drug effects
chemical_list: D017319:Photosensitizing Agents