EstimatingMitochondrialMass，可以用于线粒体肿胀的检测

Accuratemeasurementsofmitochondrialmassrequireaprobethatwillaccumulateinmitochondriaregardlessofthemitochondrialmembranepotential,apropertydisplayedbyseveralofourMitoTrackerandMitoFluordyes—MitoFluorGreen(M7502),MitoFluorRed589(M22424),MitoTrackerRed580(M22425)andMitoTrackerDeepRed633(M22426).Mitochondrialuptakeofnonylacridineorange(NAO,A1372)andMitoTrackerGreenFM(M7514)hasalsobeenreportedtobeindependentofmitochondrialmembranepotential,^1,2althoughstudieshaveshownthatthismaynotbetrueforallcelltypes.^3,4Mitochondrialstainingbynonylacridineorangeisattributedtobindingofcardiolipinintheinnermitochondrialmembrane,⁵suggestingthattheobservedfluorescencesignalmaynotcorrelatewiththe"mass"oftheentiremitochondriabutinsteadmaymeasuretheamountofinnermembranepresent.Indeed,onestudyhasshownthatmitochondrialmasscanincreasewhilethemitochondrialvolumeremainsunchanged.⁶

Mitochondrialmassvarieswithcelltypeandcanbeusefulinseparatingpopulationsofhealthycells(seeFigure1).Themitochondrialmassofacelldoeschangewithtime,asdemonstratedbythelossofmitochondrialmassinstudiesofagingcells.⁷Changesinmitochondrialmassarealsoobservedinapoptoticcells,butarenotnecessarilyassociatedwiththelossofmitochondrialmembranepotential.^6,8.

Figure1.Peripheralbloodmononuclearcells(PBMCs)stainedwithanorange-fluorescentR-phycoerythrin–labeledanti-CD3antibody(A21333)andthegreen-fluorescentMitoTrackerGreendye(M7514).Forcomparison,CD3+PBMCswithoutMitoTrackerGreenstainingareshownonthesameplot(lowerrightpopulation).ThisfiguredemonstratesthatthemitochondrialmassofPBMCsisapproximatelythesameforCD3+andCD3-individuals.

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