Photodynamic Treatment for Arthritis Promising
Joint inflammation reduced in an animal model of rheumatoid arthritis
MONDAY, April 21 (HealthDay News) -- Photodynamic treatment of inflamed joints reduces the severity of arthritis in a mouse model of rheumatoid arthritis, according to an article published online April 15 in Lasers in Surgery and Medicine.
Andreas Hansch, Ph.D., of Friedrich Schiller University of Jena in Jena, Germany, and colleagues assessed the distribution of various formulations and doses of the photosensitizer meta-tetra(hydroxyphenyl)chlorin (m-THPC) in the joints and skin of mice by using fluorescence spectrometry. Mice with antigen-induced arthritis were administered intravenous photosensitizer followed by laser photodynamic treatment. One week later, the researchers compared the histologic appearance of treated and untreated joints and assigned an arthritis score for each joint based on inflammatory changes and joint destruction.
Pegylated liposomal m-THPC was selected as the photosensitizer due to its favorable accumulation in arthritic joints. The joints that received photodynamic treatment with photosensitizer showed significant improvements in arthritic scores compared with untreated joints. There was no evidence of cartilage destruction in treated joints.
"Non-invasive treatment of inflamed joints by PDT (photodynamic treatment) reduces the severity of arthritis at the site of synovial inflammation and joint destruction. Therefore, this may be an additional therapy option for the treatment of arthritis with predominantly local effects," conclude the authors.
Photosensitizers for the study were provided by Biolitec AG.