Journal ArticleDOI
Protoporphyrin IX-induced structural and functional changes in human red blood cells, haemoglobin and myoglobin.
TLDR
Spectrophotometric studies reveal that protoporphyrin IX interacts with haemoglobin and myoglobin forming ground state complexes, which may have a role in establishing efficacy of therapeutic uses of porphyrins as well as in elucidating their mechanisms of action as therapeutic agents.Abstract:
Protoporphyrin IX and its derivatives are used as photosensitizers in the photodynamic therapy of cancer. Protoporphyrin IX penetrates into human red blood cells and releases oxygen from them. This leads to a change in the morphology of the cells. Spectrophotometric studies reveal that protoporphyrin IX interacts with haemoglobin and myoglobin forming ground state complexes. For both proteins, the binding affinity constant decreases, while the possible number of binding sites increases, as the aggregation state of the porphyrin is increased. The interactions lead to conformational changes of both haemoglobin and myoglobin as observed in circular dichroism studies. Upon binding with the proteins, protoporphyrin IX releases the heme-bound oxygen from the oxyproteins, which is dependent on the stoichiometric ratios of the porphyrin : protein. The peroxidase activities of haemoglobin and myoglobin are potentiated by the protein-porphyrin complexation. Possible mechanisms underlying the relation between the porphyrin-induced structural modifications of the heme proteins and alterations in their functional properties have been discussed. The findings may have a role in establishing efficacy of therapeutic uses of porphyrins as well as in elucidating their mechanisms of action as therapeutic agents.read more
Citations
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Journal ArticleDOI
Porphyrins and metalloporphyrins, vol. II By J. E. Falk. Pp. xiii + 266. Elsevier Publishing Co. Ltd, Amsterdam. 1964. 75s. net
Journal ArticleDOI
( R )-α-Lipoic acid inhibits fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro
Hardik Ghelani,Valentina Razmovski-Naumovski,Valentina Razmovski-Naumovski,Rajeswara Rao Pragada,Srinivas Nammi +4 more
TL;DR: Findings provide new insights into the anti-glycation properties of ALA and emphasize that ALA supplementation is beneficial in the prevention of AGEs-mediated diabetic and cardiovascular complications.
Journal ArticleDOI
Photoactive Herbal Compounds: A Green Approach to Photodynamic Therapy
TL;DR: The role of various herbal medicines either alone or in combination to enhance the therapeutic outcome of photodynamic therapy is emphasized.
Journal ArticleDOI
Influence of iron oxide nanoparticles (Fe3O4) on erythrocyte photohemolysis via photofrin and Rose Bengal sensitization
TL;DR: Photosensitization of RBC with PF or RB mixed with IO-NP inhibited rupturing erythrocyte membrane and therefore a consideration should be taken against their combination in clinical applications.
Journal ArticleDOI
Quantification of 5‐aminolevulinic acid by CE using dynamic pH junction technique
TL;DR: An online dynamic pH junction preconcentration method was developed for quantification of 5-aminolevulinic acid (ALA) by CE with the separation time less than 6 min and the sensitivity was successfully improved over 50-fold.
References
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Book
Photodynamic Therapy
TL;DR: A comprehensive review of mechanisms of subcellular and tumor localization of photosensitizing agents, as well as of molecular, cellular, and tumor responses associated with photodynamic therapy, are discussed.
Journal ArticleDOI
Determination of the secondary structures of proteins by circular dichroism and optical rotatory dispersion.
Journal ArticleDOI
Biological effects of the superoxide radical.
TL;DR: Can the superoxide radical exert deleterious effects independent of participating with H2O2 in the production of the hydroxyl radical?
Journal ArticleDOI
5-Aminolevulinic acid-based photodynamic therapy. Clinical research and future challenges.
Qian Peng,Trond Warloe,Kristian Berg,Johan Emelian Moan,Magne Kongshaug,Karl Erik Giercksky,Jahn M. Nesland +6 more
TL;DR: Studies have shown that a higher accumulation of ALA‐derived PpIX in rapidly proliferating cells may provide a biologic rationale for clinical use of ALa‐based PDT and diagnosis, however, no review updating the clinical data has appeared so far.