title: Measurement of H2O2 within living Drosophila during aging using a ratiometric mass spectrometry probe targeted to the mitochondrial matrix.
abstract: Hydrogen peroxide (H(2)O(2)) is central to mitochondrial oxidative damage and redox signaling, but its roles are poorly understood due to the difficulty of measuring mitochondrial H(2)O(2) in vivo. Here we report a ratiometric mass spectrometry probe approach to assess mitochondrial matrix H(2)O(2) levels in vivo. The probe, MitoB, comprises a triphenylphosphonium (TPP) cation driving its accumulation within mitochondria, conjugated to an arylboronic acid that reacts with H(2)O(2) to form a phenol, MitoP. Quantifying the MitoP/MitoB ratio by liquid chromatography-tandem mass spectrometry enabled measurement of a weighted average of mitochondrial H(2)O(2) that predominantly reports on thoracic muscle mitochondria within living flies. There was an increase in mitochondrial H(2)O(2) with age in flies, which was not coordinately altered by interventions that modulated life span. Our findings provide approaches to investigate mitochondrial ROS in vivo and suggest that while an increase in overall mitochondrial H(2)O(2) correlates with aging, it may not be causative.
authors.affiliation: Medical Research Council Mitochondrial Biology Unit, Hills Road, Cambridge CB2 0XY, UK.
authors.forename: Helena M
authors.initials: HM
authors.lastname: Cochemé
authors.forename: Caroline
authors.initials: C
authors.lastname: Quin
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: McQuaker
authors.forename: Filipe
authors.initials: F
authors.lastname: Cabreiro
authors.forename: Angela
authors.initials: A
authors.lastname: Logan
authors.forename: Tracy A
authors.initials: TA
authors.lastname: Prime
authors.forename: Irina
authors.initials: I
authors.lastname: Abakumova
authors.forename: Jigna V
authors.initials: JV
authors.lastname: Patel
authors.forename: Ian M
authors.initials: IM
authors.lastname: Fearnley
authors.forename: Andrew M
authors.initials: AM
authors.lastname: James
authors.forename: Carolyn M
authors.initials: CM
authors.lastname: Porteous
authors.forename: Robin A J
authors.initials: RA
authors.lastname: Smith
authors.forename: Saima
authors.initials: S
authors.lastname: Saeed
authors.forename: Jane E
authors.initials: JE
authors.lastname: Carré
authors.forename: Mervyn
authors.initials: M
authors.lastname: Singer
authors.forename: David
authors.initials: D
authors.lastname: Gems
authors.forename: Richard C
authors.initials: RC
authors.lastname: Hartley
authors.forename: Linda
authors.initials: L
authors.lastname: Partridge
authors.forename: Michael P
authors.initials: MP
authors.lastname: Murphy
mesh_terms: D000375:Aging; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004330:Drosophila / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000032:analysis*; D008928:Mitochondria / Q000378:metabolism*; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000737:chemistry; D010636:Phenols / Q000032:analysis* / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C558697:MItoB compound; C558698:MItoP compound; D009943:Organophosphorus Compounds; D010636:Phenols; D006861:Hydrogen Peroxide