Background And Objectives: Photodynamic therapy (PDT) of superficial bladder cancer may cause damages to the normal surrounding bladder wall. Prevention of these is important for bladder healing. We studied the influence of photosensitizer concentration, irradiation parameters, and production of reactive oxygen species (ROS) on the photodynamically induced damage in the porcine urothelium invitro. The aim was to determine the threshold conditions for the cell survival.
Methods: Living porcine bladder mucosae were incubated with solution of hexylester of 5-aminolevulinic acid (HAL). The mucosae were irradiated with increasing doses and cell alterations were evaluated by scanning electron microscopy and by Sytox green fluorescence. The urothelial survival score was correlated with Protoporphyrin IX (PpIX) photobleaching and intracellular fluorescence of Rhodamine 123 reflecting the ROS production.
Results: The mortality ratio was dependent on PpIX concentration. After 3 hours of incubation, the threshold radiant exposures for blue light were 0.15 and 0.75 J/cm(2) (irradiance 30 and 75 mW/cm(2), respectively) and for white light 0.55 J/cm(2) (irradiance 30 mW/cm(2)). Photobleaching rate increased with decreasing irradiance. Interestingly, the DHR123/R123 reporter system correlated well with the threshold exposures under all conditions used.
Conclusions: We have determined radiant exposures sparing half of normal urothelial cells. We propose that the use of low irradiance combined with systems reporting the ROS production in the irradiated tissue could improve the in vivo dosimetry and optimize the PDT.
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http://dx.doi.org/10.1002/lsm.20416 | DOI Listing |
ACS Nano
January 2025
State Key Laboratory of Fine Chemicals, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518055, China.
Biofilm-induced chronic bacterial infections represent a significant challenge in modern medicine due to their resistance to conventional antibiotic treatments. Although photodynamic therapy (PDT) has emerged as a promising antibiotic-free antibacterial strategy, the hypoxic condition within biofilms and the lack of an effective local drug delivery system have limited the clinical effectiveness of photosensitizer (PS) agents. Herein, we propose a type of charge regulation-enhanced type I PS-loaded hydrogel dressing for treating biofilm infection.
View Article and Find Full Text PDFFront Pharmacol
December 2024
Department of Radiology, Tianjin Key Laboratory of Functional Imaging and Tianjin Institute of Radiology, Tianjin Medical University General Hospital, Tianjin, China.
Introduction: Although photodynamic therapy (PDT) shows considerable potential for cancer treatment due to its precise spatial control and reduced toxicity, effectively eliminating residual cells under hypoxic conditions remains challenging because of the resistance conferred by these cells.
Methods: Herein, we synthesize an amphiphilic PEGylated polyphosphoester and present a nanocarrier (NP) specifically designed for the codelivery of hydrophobic photosensitizer (chlorin e6, Ce6) and hypoxia-activated prodrugs (tirapazamine, TPZ). We investigate the antitumor effect of NP on both cellular and animal level.
Int J Nanomedicine
January 2025
State Key Laboratory of Ophthalmology, Optometry and Visual Science, National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China.
Background: Developing carrier-free nanomedicines via self-assembly of two antitumor drug molecules is a potential strategy for enhancing the combination treatment of tumors. Similarly, conventional chemotherapy combined with photodynamic therapy may synergistically improve the antitumor effect while minimizing the adverse reactions associated with antitumor treatment. Hyaluronic acid (HA) can bind to overexpressed HA receptors on the tumor cell surface, increasing cell internalization and resulting in good tumor-targeting properties.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for AIE Research, Guangdong Provincial Key Laboratory of New Energy Materials Service Safety, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, P. R. China.
Developing small organic molecular phototheranostic agents with second near-infrared (NIR-II) aggregation-induced emission (AIE) is paramount for the phototriggered diagnostic imaging and synchronous in situ therapy of cancer via an excellent balance of the excited states energy dissipations. In this study, a multifunctional iridium(III) complex is exploited by the coordination of an AIE-active N^N ancillary ligand with a trivalent iridium ion. The resultant complex DPTPzIr significantly outperforms its parent ligand in terms of absorption/emission wavelengths, reactive oxygen species (ROS) production, and photothermal conversion, which simultaneously endow DPTPzIr nanoparticles with matched absorption peak to commercial 808 nm laser, the longest NIR-II emission peak (above 1100 nm) among those previously reported AIE iridium(III) complexes, potentiated type-I ROS generation, and as high as 60.
View Article and Find Full Text PDFBull Exp Biol Med
January 2025
Institute of Veterinary Medicine and Biotechnology, Novosibirsk State Agrarian University, Novosibirsk, Russia.
We conducted a comparative study of the mammary gland microbiota in female Wistar rats and the microbiota associated with breast cancer (BC) induced by the administration of N-methyl-N-nitrosourea, after surgical treatment, photodynamic therapy (PDT), and chemotherapy (CT). Selective nutrient media and a smear-fingerprint technique were used to study the microbiota. Staphylococcus, Streptococcus, and Lactobacillus were found in the mammary glands of intact rats.
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