Biomaterial Database

Electron-transfer mechanisms in photosensitization by the anti-inflammatory drug benzydamine. 1998

D E Moore, and J Wang

School of Pharmacy, University of Sydney, Australia. demoore@pharm.usyd.edu.au

The novel anti-inflammatory drug benzydamine has been show to photosensitize the reduction of Nitro Blue Tetrazolium, ferricytochrome c and copper (II) bathocuproinedisulphonate in aqueous solutions (pH 7.4, 30 degrees C) when irradiated with UV light at its maximum absorption wavelength of 308 nm. The reduction reactions all proceed most efficiently when the solutions are deoxygenated, clearly indicating that direct electron transfer occurs from the excited state of the sensitizer to the substrate. In aerated solutions the reduction reactions are slower and are partially inhibited by superoxide dismutase, suggesting that superoxide anion could be involved as an intermediate when oxygen is present. Benzydamine also photosensitizes the oxidation of 1-histidine and 2,5-dimethylfuran by the singlet oxygen pathway in aerated solutions. The ability of benzydamine to participate as sensitizer in several types of photochemical reaction is relevant to the observed clinical photosensitivity of the drug.

UI	MeSH Term	Description	Entries
D009580	Nitroblue Tetrazolium	Colorless to yellow dye that is reducible to blue or black formazan crystals by certain cells; formerly used to distinguish between nonbacterial and bacterial diseases, the latter causing neutrophils to reduce the dye; used to confirm diagnosis of chronic granulomatous disease.	Nitro-BT,Nitrotetrazolium Blue,Tetrazolium Nitroblue,Blue, Nitrotetrazolium,Nitroblue, Tetrazolium,Tetrazolium, Nitroblue
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D010777	Photochemistry	A branch of physical chemistry which studies chemical reactions, isomerization and physical behavior that may occur under the influence of visible and/or ultraviolet light.	Photochemistries
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D003574	Cytochrome c Group	A group of cytochromes with covalent thioether linkages between either or both of the vinyl side chains of protoheme and the protein. (Enzyme Nomenclature, 1992, p539)	Cytochromes Type c,Group, Cytochrome c,Type c, Cytochromes
D004579	Electron Transport	The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)	Respiratory Chain,Chain, Respiratory,Chains, Respiratory,Respiratory Chains,Transport, Electron
D000894	Anti-Inflammatory Agents, Non-Steroidal	Anti-inflammatory agents that are non-steroidal in nature. In addition to anti-inflammatory actions, they have analgesic, antipyretic, and platelet-inhibitory actions. They act by blocking the synthesis of prostaglandins by inhibiting cyclooxygenase, which converts arachidonic acid to cyclic endoperoxides, precursors of prostaglandins. Inhibition of prostaglandin synthesis accounts for their analgesic, antipyretic, and platelet-inhibitory actions; other mechanisms may contribute to their anti-inflammatory effects.	Analgesics, Anti-Inflammatory,Aspirin-Like Agent,Aspirin-Like Agents,NSAID,Non-Steroidal Anti-Inflammatory Agent,Non-Steroidal Anti-Inflammatory Agents,Nonsteroidal Anti-Inflammatory Agent,Anti Inflammatory Agents, Nonsteroidal,Antiinflammatory Agents, Non Steroidal,Antiinflammatory Agents, Nonsteroidal,NSAIDs,Nonsteroidal Anti-Inflammatory Agents,Agent, Aspirin-Like,Agent, Non-Steroidal Anti-Inflammatory,Agent, Nonsteroidal Anti-Inflammatory,Anti-Inflammatory Agent, Non-Steroidal,Anti-Inflammatory Agent, Nonsteroidal,Anti-Inflammatory Analgesics,Aspirin Like Agent,Aspirin Like Agents,Non Steroidal Anti Inflammatory Agent,Non Steroidal Anti Inflammatory Agents,Nonsteroidal Anti Inflammatory Agent,Nonsteroidal Anti Inflammatory Agents,Nonsteroidal Antiinflammatory Agents
D001591	Benzydamine	A benzyl-indazole having analgesic, antipyretic, and anti-inflammatory effects. It is used to reduce post-surgical and post-traumatic pain and edema and to promote healing. It is also used topically in treatment of RHEUMATIC DISEASES and INFLAMMATION of the mouth and throat.	Benzindamine,Benzidamine,Benzydamine Hydrochloride,Benzydamine Monohydrochloride,Difflam,Lonol,Novo-Benzydamine,Opalgyne,PMS-Benzydamine,Ratio-Benzydamine,Rosalgin,Sun-Benz,Tantum,Tantum Topico,Hydrochloride, Benzydamine,Monohydrochloride, Benzydamine,Novo Benzydamine,PMS Benzydamine,Ratio Benzydamine,Sun Benz
D013482	Superoxide Dismutase	An oxidoreductase that catalyzes the reaction between SUPEROXIDES and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide.	Hemocuprein,Ag-Zn Superoxide Dismutase,Cobalt Superoxide Dismutase,Cu-Superoxide Dismutase,Erythrocuprein,Fe-Superoxide Dismutase,Fe-Zn Superoxide Dismutase,Iron Superoxide Dismutase,Manganese Superoxide Dismutase,Mn-SOD,Mn-Superoxide Dismutase,Ag Zn Superoxide Dismutase,Cu Superoxide Dismutase,Dismutase, Ag-Zn Superoxide,Dismutase, Cobalt Superoxide,Dismutase, Cu-Superoxide,Dismutase, Fe-Superoxide,Dismutase, Fe-Zn Superoxide,Dismutase, Iron Superoxide,Dismutase, Manganese Superoxide,Dismutase, Mn-Superoxide,Dismutase, Superoxide,Fe Superoxide Dismutase,Fe Zn Superoxide Dismutase,Mn SOD,Mn Superoxide Dismutase,Superoxide Dismutase, Ag-Zn,Superoxide Dismutase, Cobalt,Superoxide Dismutase, Fe-Zn,Superoxide Dismutase, Iron,Superoxide Dismutase, Manganese