title: Are the mitochondrial respiratory complexes blocked by NO the targets for the laser and LED therapy?
abstract: Effects of laser (442 and 532 nm) and light-emitting diode (LED) (650 nm) radiation on mitochondrial respiration and mitochondrial electron transport rate (complexes II-III and IV) in the presence of nitric oxide (NO) were investigated. It was found that nitric oxide (300 nM-10 μM) suppresses mitochondrial respiration. Laser irradiation of mitochondria (442 nm, 3 J cm(-2)) partly restored mitochondrial respiration (approximately by 70 %). Irradiation with green laser (532 nm) or red LED (650 nm) in the same dose had no reliable effect. Evaluation of mitochondrial electron transport rate in complexes II-III and IV and effects of nitric oxide demonstrated almost similar sensitivity of complex II-III and IV to NO, with approximately 50 % inhibition at NO concentration of 3 μM. Subsequent laser or LED irradiation (3 J cm(-2)) showed partial recovery of electron transport only in complex IV and only under irradiation with blue light (442 nm). Our results support the hypothesis of the crucial role of cytochrome c oxidase (complex IV) in photoreactivation of mitochondrial respiration suppressed by NO.
authors.affiliation: Department of General and Medical Biophysics, NI Pirogov Russian National Research Medical University, 1 Ostrovityanov str, 117997, Moscow, Russia, evgenii.sci@gmail.com.
authors.forename: Evgeny A
authors.initials: EA
authors.lastname: Buravlev
authors.forename: Tatyana V
authors.initials: TV
authors.lastname: Zhidkova
authors.forename: Anatoly N
authors.initials: AN
authors.lastname: Osipov
authors.forename: Yury A
authors.initials: YA
authors.lastname: Vladimirov
mesh_terms: D000818:Animals; D042963:Electron Transport Complex II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014450:Electron Transport Complex III / Q000037:antagonists & inhibitors / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000037:antagonists & inhibitors / Q000378:metabolism*; D054020:Lasers, Gas; D028022:Low-Level Light Therapy; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism* / Q000528:radiation effects; D009569:Nitric Oxide / Q000494:pharmacology*; D010101:Oxygen Consumption; D051381:Rats
chemical_list: D009569:Nitric Oxide; D042963:Electron Transport Complex II; D003576:Electron Transport Complex IV; D014450:Electron Transport Complex III