Background: PDT represents a very localized and non-mutagen antitumoral treatment using a photosensitive molecule (porphyrin family) light activated. The first way of cell damage is a direct one, active on the very site where ROSs have been produced. The second one is indirect by activating and transmitting the processes of cellular death signaling.
View Article and Find Full Text PDFThe HMG-CoA reductase inhibitors are a class of drugs also known as statins. These drugs are effective and widely prescribed for the treatment of hypercholesterolemia and prevention of cardiovascular morbidity and mortality. Seven statins are currently available: atorvastatin, fluvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin and simvastatin.
View Article and Find Full Text PDFIn the course of a Photodynamic Therapy (PDT) protocol, disaggregation of the sensitizer upon binding to plasma proteins and lipoproteins is one of the first steps following intravenous administration. This step governs its subsequent biodistribution and has even been evoked as possibly orientating mechanism of tumor destruction. It is currently admitted as being mainly dependent on sensitizer's hydrophobicity.
View Article and Find Full Text PDFPhotodynamic therapy (PDT) has recently been proposed as a possible indication in the conservative treatment of hereditary retinoblastoma. In order to create photosensitizers with enhanced targeting ability toward retinoblastoma cells, meso-tetraphenylporphyrins bearing one glycodendrimeric moiety have been synthesized. The binding properties to plasma proteins and photodynamic activity of two monodendrimeric porphyrins bearing three mannose units via monoethylene glycol (1) or diethylene glycol (2) linkers have been compared to that of the non-dendrimeric tri-substituted derivative [TPP(p-Deg-O-α-ManOH)(3)].
View Article and Find Full Text PDFIn this paper, we discuss the evolution over the last 15 years in the Curie Institute of the concept, the development of the design and some properties of glycoconjugated photosensitizers with the aim to optimize the tumor targeting in photodynamic therapy. By this research, we have shown that specific interactions between a mannose-lectin and trimannosylglycodendrimeric porphyrins contributed to a larger extent than non-specific ones to the overall interaction of a glycosylated tetraarylporphyrin with a membrane. The studies of in vitro photocytotoxicity showed the relevance of the global geometry of the photosensitizer, the number and position of the linked glycopyranosyl groups on the chromophore and their lipophilicity.
View Article and Find Full Text PDFTetrapyrrole rings possess four nitrogen atoms, two of which act as Bröndsted bases in acidic media. The two protonation steps occur on a close pH range, particularly in the case of meso-tetraphenylporphyrin (TPP) derivatives. If the cause of this phenomenon is well known--a protonation-induced distortion of the porphyrin ring--data on stepwise protonation constants and on electronic absorption spectra of monoprotonated TPPs are sparse.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
April 2010
Background: Photodynamic therapy is an established cancer treatment in which a photosensitizing agent is activated by exposure to light thus generating cytotoxic reactive oxygen species that cause cellular damage.
Methods: A new photosensitizer synthesized at Curie Institute was used to treat retinoblastoma xenografts in mice, a glycoconjugated meso substituted porphyrin derivative, that showed some retinoblastoma cell affinity. The longitudinal follow-up of the tumors was carried out by (23)Na MRI (without adding exogenous contrast agents) to map the extracellular compartment and to characterize cell packing.