I-methylene blue nama-mitochondria: ukuthuthwa kwama-electron nobufakazi

Cabanga ngamalungiselelo amabili okuhlola abekwe eceleni kwelinye nelinye. Womabili aqukethe ama-mitochondria obuchopho afakwe ubuthi nge-rotenone, ikhemikhali evimba i-Complex I yochungechunge lokuphefumula. Kwelinye, umhloli ufaka nge-pipette inani le-methylene blue elisesilinganisweni se-micromolar. Ukusetshenziswa komoya-mpilo kubuyela ngokwengxenye. Umehluko we-voltage kulwelwesi ubuyela ngokwengxenye. Ukukhiqizwa kwe-ATP okuncane kuyaqala futhi. Ku-cuvette eseduze, inzwa ye-peroxide iveza enye ingxenye yendaba: ukukhishwa kwe-hydrogen peroxide sekuphindaphindeke kaningi, kuwo wonke amazinga enani ahloliwe, nangaphansi kwawo wonke ama-substrate azanyiwe.

Zombili izilinganiso zilungile. I-methylene blue ingumthuthi wama-electron ongagcina ukugeleza kukagesi kudlula ingxenye eyonakele yochungechunge lokuphefumula, futhi lowo mthuthi ofanayo ubiza intengo ye-peroxide ngesikhathi enza lokhu. Uma ugcina womabili la maqiniso engqondweni, imibhalo yesayensi emayelana ne-methylene blue nokusebenza kwama-mitochondria iyaqondakala. Uma ugcina elilodwa kuphela, ifundeka njengesimangaliso noma njengengozi, kuye ngokuthi iyiphi indatshana yesayensi oyivule kuqala.

Umthuthi, uchazwe ngokucacile

Uchungechunge lokuphefumula luwumugqa wokudlulisela. Ama-electron angena ku-Complex I (esuka ku-NADH) noma ku-Complex II nama-enzyme e-flavin ahlobene nayo (esuka ku-succinate nakwabanye abanikeli abafanayo), adlule ku-Complex III aye kumthwali ohambayo, i-cytochrome c, bese edlula ku-Complex IV aye emoyeni-mpilo. Ukudlulisela ngakunye kupompa ama-proton anqamule ulwelwesi lwangaphakathi, futhi umehluko wokugxila owumphumela ushukumisa ukukhiqizwa kwe-ATP. Uma noma yisiphi isiteshi sivinjiwe, umugqa ongaphambi kwaso uyathula.

I-methylene blue ingena njengomthuthi ohamba ngomzila ohambisana nowokuqala. Isimo sayo esenziwe i-oxidation samukela ama-electron kubathwali abangaphambi kwendawo evinjiwe, siguquke sibe yisimo esingenambala esenziwe i-reduction, i-leucomethylene blue, esibe sesidlulisela lawo ma-electron kwabalandelayo bese sibuyela ekubeni luhlaza okwesibhakabhaka. Lezi zimo ezimbili zichazwe encazelweni yombhangqwana we-redox, kanti indlela ebanzi yokudlulisela ichazwe encazelweni yendlela yokusebenza evamile. Umbuzo ongakaphendulwa uwukuthi umthuthi ubuyela kuphi emgqeni: endaweni yokubopha i-quinol ku-Complex III eyaziwa ngokuthi indawo ye-Qo, noma ngokuqondile ku-cytochrome c. Ukuthi iyiphi indlela yokuphuma esetshenziswa kakhulu kuya ngezimo, njengoba ukuhlaziywa kokudlula i-Complex III kuchaza ngokuningiliziwe.

Lokho izifundo ezintathu zamagundane ezakulinganisa ngempela

Zontathu izifundo zasebenzisa ama-mitochondria obuchopho ahlukanisiwe, okusho izitho ezincane zeseli ezikhishwe eselini zafakwa oketshezini oluchaziwe olugcina i-pH izinzile. Azikho izeli eziphelele, azikho izilwane ezanikezwa into ehlolwayo, futhi abekho abantu ababambe iqhaza. Amazinga okugxila abhekisela oketshezini oluzungeze lezi zitho ezincane, hhayi enanini umuntu alithatha ngomlomo. Uma ugcina lo mongo ungaguquki, izinombolo zikhuluma ngokucacile.

Ucwaningo lokuqala, kuma-mitochondria ahlukanisiwe obuchopho bengulube yasendle encane emazingeni asuka ku-100 nanomolar kuya ku-2 micromolar, lwahlola inzuzo nentengo kulungiselelo olulodwa. Kuma-mitochondria aphilile, udayi wandisa ukusetshenziswa komoya-mpilo ngesikhathi sokuphumula kodwa awuzange ushintshe ukuphefumula okushukunyiswa yi-ADP, ngakho ukukhiqizwa kwe-ATP okuhambisana nokuphefumula akuzange kuthuthuke. Lapho i-Complex I ivinjiwe, i-2 micromolar yabuyisela ukukhiqizwa kwe-ATP kusuka ku-46 kuya ku-93 nanomoles ngomzuzu nge-milligram, uma kuqhathaniswa nezinga elivamile eliseduze no-1109. Lapho i-Complex III ivinjiwe, inani elifanayo labuyisela i-ATP kusuka cishe ku-46 kuya ku-63, uma kuqhathaniswa nezinga elivamile eliseduze no-910. I-voltage nokumuncwa kwe-calcium kwabuyela ngokwengxenye. Ukuvinjwa kwe-Complex IV nge-cyanide kwakungenakudlulwa, okubeka indawo ewusizo yokuphuma kwama-electron ngaphambi kwe-Complex IV esebenzayo. Konke ukubuyiselwa kokusebenza kwakukhona ngokwezibalo futhi kukuncane: amaphesenti ayidijithi eyodwa okukhiqizwa kwe-ATP okuvamile.

Ucwaningo lwesibili, kuma-mitochondria engxenye engaphandle yobuchopho begundane elincane cishe ku-1 micromolar, lwaqinisekisa ukudlula i-Complex I futhi lwabeka umngcele ku-Complex III. I-rotenone yehlisa ukuphefumula kusuka cishe ku-121 kuya ngaphansi kuka-2 nanomoles womoya-mpilo ngomzuzu nge-milligram, udayi wase ulukhuphula lwaya cishe ku-21, okucishe kube ingxenye eyodwa kweziyisithupha yezinga elivamile, kuyilapho i-voltage yolwelwesi ibuyela cishe ngokuphelele. Kodwa ngemva kokuvinjwa kwe-Complex III, akukho ukuphefumula noma i-voltage okwabuyela emazingeni asuka ku-1 kuya ku-5 micromolar, futhi ukuvinjwa kwacindezela isignali ye-peroxide eqhutshwa udayi. Ababhali baphakamisa ukuthi udayi osenziwe i-reduction uletha ama-electron awo endaweni ye-Qo ye-Complex III: uma leyo ndawo ithathiwe, umthuthi akanandawo yokuwaletha.

Ucwaningo lwesithathu, kuma-mitochondria obuchopho begundane elincane, igundane elikhulu nengulube yasendle encane, ikakhulukazi ku-2 micromolar, lwahlola ngokuqondile lokhu kungavumelani lwathola ukuthi ukuvinjwa kwe-Complex III kungadlulwa. Lapho i-myxothiazol, evimba indawo ye-Qo, yehlisa ukuphefumula okuyisisekelo ngamaphesenti angu-88, udayi wabuyisela ukusetshenziswa komoya-mpilo cishe kumaphesenti angu-62 ezinga elingavinjiwe. Ekuhloleni okuqondile, ingxenye ye-micromolar yenza i-reduction ye-cytochrome c eyengezwe ivela ngaphandle ngisho nalapho i-Complex III ivinjiwe, okusekela umzila osuka ku-NADH udlule kudayi uye ku-cytochrome c uqhubekele ku-Complex IV. Kodwa ukuphefumula okubuyiselwe kwaziphatha ngendlela engavamile: i-ADP eyengeziwe yehlisa ukusetshenziswa komoya-mpilo esikhundleni sokukukhuphula, futhi ukuvimba ukukhiqizwa kwe-ATP kwashukumisa ukuphefumula. I-voltage yabuyiselwa ngokwengxenye kuphela. Ukusetshenziswa okuphezulu komoya-mpilo lapho ukuhlangana kwezinqubo kuphendukezelwe akukhona ukukhiqizwa kwamandla okuvamile.

Kungani amalabhorethri engavumelani, nokuthi yini ecacisa lokhu

Incazelo esekelwe ohlotsheni lwesilwane iyehluleka kuqala. Iqembu lesithathu laphinda umsebenzi ezinhlotsheni ezintathu zamagundane futhi lathola ukudlula okufanayo ngokwendlela okwenzeka ngayo kuzo zonke, kuhlanganise nohlobo lwegundane elincane okwakubikwe ukuthi lokhu kudlula akwenzeki kulo. Okwehlukile esikhundleni salokho yizinga lokugxila (1 uma kuqhathaniswa no-2 micromolar), amanani ezivimbeli, uketshezi olugcina i-pH izinzile, izindlela zokuhlukanisa, futhi ngaphezu kwakho konke isimo samandla esiqhathaniswayo: ukudlula kubonakala ngokucacile kakhulu ngaphambi kokufakwa kwe-ADP, okuyilapho kanye kuvela khona ukusabela kwe-ADP okuphambene nokulindelekile. Ngakho umdwebo othembekile ubonisa izindlela ezimbili zokuphuma ezincike ezimweni, enye isendaweni ye-Qo kanti enye iku-cytochrome c. Umthuthi uletha lapho amakhemikhali endawo emvumela khona.

Intengo ye-peroxide

Uhlangothi lwentengo luyavumelana njengoba kuvumelana uhlangothi lokubuyiselwa kokusebenza. Emsebenzini wengulube yasendle encane, udayi wandisa ukukhishwa kwe-peroxide ngaphansi kwazo zonke izimo ezahlolwa, ngesikhathi sokuphumula, ngesikhathi sokukhiqiza i-ATP nalapho ukusebenza kuphazanyiswe ngamakhemikhali, kuwo womathathu ama-substrate. Ngesikhathi sokukhiqizwa kwe-ATP, ukukhishwa kwakhuphuka kusuka cishe ku-148 kuya ngaphezu kuka-1500 picomoles ngomzuzu nge-milligram ku-1 micromolar, futhi ngisho ne-100 nanomolar yandisa isignali yaba ngaphezu kokuphindwe kane. Udayi waphinde wehlisa isivinini sokususwa kwe-peroxide cishe ngokuphindwe ku-2.6, ngakho isignali ibonisa ukwakheka okusheshayo kanye nokususwa okuhamba kancane. Indlela yamakhemikhali ehlongozwayo iwukwenziwa kwe-reduction yomoya-mpilo ngokuqondile ngudayi osenziwe i-reduction ngaphandle kwe-superoxide etholakalayo, nakuba lokhu kuseyincazelo yokuhumusha imiphumela kunokuba kube isinyathelo esifakazelwe.

Umsebenzi wamagundane amancane wenza isithombe sibe nzima ngendlela ewusizo. I-peroxide yakhuphuka kakhulu ngokwanda kwenani, kusuka ezingeni lokuqala eliseduze no-76 kuya cishe ku-2000 picomoles ngomzuzu nge-milligram ku-2 micromolar, kodwa ukuvinjwa kwe-Complex III kwacindezela ingxenye eqhutshwa udayi. Ukube i-peroxide ibivela kuphela ekusabeleni kukadayi osenziwe i-reduction nomoya-mpilo, ukuvimba uchungechunge bekungafanele kube nomthelela omkhulu kangaka. Kunomthelela, ngakho uchungechunge luyahlanganyela. Ukubuyekezwa kokuvimbela nokukhuthaza i-oxidation kubeka lezi zici ezimbili emongweni obanzi, futhi ukuhlaziywa komoya-mpilo uma kuqhathaniswa ne-ATP kuchaza ukuthi kungani izinombolo zomoya-mpilo zizodwa zingasoze zaqinisekisa isimangalo samandla.

Ukubuyisela ukusebenza akukhona ukulungisa

Inkulumo okudingeka iyekwe ithi, "ingabe i-methylene blue ilungisa ama-mitochondria." Ukulungisa kungasho ukulungiswa okuhlala isikhathi eside: izingxenye ezakhiwe kabusha, ukuhlangana kwezinqubo okuqhubeka ngemva kokuba umuthi usuhambile, ukubuyela kokusebenza kumaseli aphelele, bese kuba ngcono ukusebenza esidalweni esiphilayo. Ayikho kulezi zindatshana ezintathu ebonisa lokho. Zibonisa ukushintshwa ngokushesha komzila ezithweni ezincane ezisanda kuhlukaniswa ngesikhathi sokuvinjwa okwenziwe ngamakhemikhali, lapho ukukhiqizwa kwe-ATP kuyizingxenye ezincane zokuvamile futhi ngezinye izikhathi ukuhlangana kwezinqubo kungajwayelekile ngempela. I-rotenone ne-antimycin kungamathuluzi aselabhorethri, hhayi amamodeli okuguga noma esifo sama-mitochondria kubantu, futhi akukho kulokhu okungahunyushwa njengamandla engeziwe kumuntu ophilile, okuwumbuzo ohlukile wobufakazi onemibhalo yawo yocwaningo kubantu.

Imingcele emithathu igcina noma yisiphi isiphetho se-biohacking sithembekile. Okokuqala, izinga lokugxila oketshezini alilona inani elithathwayo: i-0.1 kuya ku-2 micromolar ezungeze izitho ezincane ezihlukanisiwe ayisho lutho ngokuthi yiliphi inani elithathwa ngomlomo eliveza lelo zinga elikhululekile ku-mitochondrion yobuchopho bomuntu, ikakhulukazi ngoba udayi uyanqwabelana noma ukhululwe kuye nge-voltage yolwelwesi uqobo. Okwesibili, umoya-mpilo awuwona amandla: udayi ungandisa ukusetshenziswa komoya-mpilo ngokujikeleza nokuvuza kanye nangokufakwa kwe-phosphate okukhiqizayo, ngakho ukulinganisa ukuphefumula ngaphandle kwezilinganiso ze-ATP ne-voltage akukwazi ukusekela isimangalo samandla. Okwesithathu, inzuzo nomthwalo kufanele kube emshweni owodwa: noma yisiphi isitatimende sokubuyiselwa kwe-voltage noma kwe-ATP esishiya ngaphandle ukwanda kwe-peroxide okuhambisana nakho sibika ukuhlola ngokungafanele. Okunye okubalulekile ekucaciseni lokhu kuhlanganisa ibhalansi ye-redox ye-NAD, ukwakheka kokusabela ngokwenani kanye nomhlahlandlela wezindlela zokuhlola.

Inothi elilodwa elisebenzisekayo: ukuthutha kuyisici saleyo molekyuli ethile ngqo. Izihlobo ezikhishwe amaqembu e-methyl, njenge-Azure B, nazo zisebenza ku-redox, kodwa ngokuziphatha okuhlukile, ngakho isixazululo esonakele ngokwengxenye siwukuhlola okuhlukile kunodayi ongakaguquki. Lesi ngesinye sezizathu zokufuna imininingwane egcwele yezinga le-pharmacopeia nombhalo oshicilelwe weqoqo lokukhiqiza esikhundleni sokuhlolwa kwezinsimbi kuphela. Ukusabela kwamakhemikhali okuqhutshwa ukukhanya kwengeza esinye isixwayiso esifanayo ekusetshenzisweni lapho kukhona ukukhanya, esichazwe ngaphansi kokuhlanganiswa nokukhanya okubomvu.

Isimangalo esilinganiselwe sisamile naphezu kwakho konke lokhu futhi sifanele ukugcinwa: i-methylene blue ingasebenza njengomthuthi wama-electron oncike ezimweni kuma-mitochondria awonakele ahlukanisiwe, igcine ukugeleza ngokwengxenye ngentengo ye-peroxide. Konke okungaphezu kwalokho, amandla, ukuphila isikhathi eside, ukulungisa, kusalinde ubufakazi lezi zifundo ezazingaklanyelwe neze ukubunikeza.