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
Heme cytotoxicity and the pathogenesis of immune-mediated inflammatory diseases.
TL;DR: Targeting “free heme” may be used as a therapeutic intervention against diseases related to oxidative stress and immune-mediated inflammatory conditions.
Journal ArticleDOI
Characterization of a Mycobacterium tuberculosis Nanocompartment and Its Potential Cargo Proteins
Heidi Contreras,Matthew S. Joens,Lisa M. McMath,Vincent P. Le,Michael V. Tullius,Jacqueline M. Kimmey,Neda Bionghi,Marcus A. Horwitz,James A. J. Fitzpatrick,Celia W. Goulding +9 more
TL;DR: It is shown by co-purification and electron microscopy that mycobacteria via Mt-Enc can encapsulate Mt-DyP, Mt-BfrB, and Mt-FolB, which may aid in detoxification of the local environment to ensure long term survival.
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Pulmonary Proteases in the Cystic Fibrosis Lung Induce Interleukin 8 Expression from Bronchial Epithelial Cells via a Heme/Meprin/Epidermal Growth Factor Receptor/Toll-like Receptor Pathway
TL;DR: It is shown that the Pseudomonas proteases and the neutrophil proteases (neutrophil elastase (NE) and proteinase-3) are capable of almost complete degradation of hemoglobin in vitro but that NE is the predominant protease that cleaves hemoglobinIn vivo in CF bronchoalveolar lavage fluid.
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Role of the c-Jun N-terminal kinase signaling pathway in SW480 cell apoptosis in response to 5-aminolevulinic acid-based photodynamic therapy
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Enhancement techniques for improving 5-aminolevulinic acid delivery through the skin
TL;DR: Enhanced delivery systems for ALA in the skin will play an important role in ALA-PDT, and several enhancement techniques for increasing ALA permeation through the skin are introduced.
References
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Journal ArticleDOI
Clinical and preclinical photodynamic therapy
TL;DR: An overview of photosensitizers, photochemistry, photobiology, and the lasers involved in photodynamic therapy is provided.
Journal ArticleDOI
Porphyrin-lipoprotein association as a factor in porphyrin localization
TL;DR: Systemic administration of the tumor-localizing product hematoporphyrin derivative to mice bearing the Lewis-Lung tumor leads to an initial distribution of porphyrins among plasma lipoproteins and albumin, and the distribution pattern is correlated with the relative numbers of LDL receptors in different tissues.
Journal ArticleDOI
The Multiple Functions of Hemoglobin
TL;DR: Several parallel biological functions of hemoglobin besides its basic function of oxygen transport are discussed and hemoglobin as source of physiological active catabolites is discussed.
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Photodynamic therapy with photofrin II induces programmed cell death in carcinoma cell lines.
TL;DR: It is indicated that although apoptosis can occur during photodynamic therapy‐induced cell death, this response is not universal for all cancer cell lines.