Indlela i-methylene blue engena ngayo kumaseli: ukuredukswa, ukwenziwa i-oxidation kabusha, nokuhlukaniseka olwelwesini

Uma ubuka amaseli e-endothelium esitsheni emunca i-methylene blue, incazelo ebonakala isobala nayo iyona engalungile. Uketshezi lokukhulisela amaseli lulahlekelwa umbala walo oluhlaza okwesibhakabhaka, amaseli athola izinhlayiyana eziluhlaza okwesibhakabhaka, ngakho kubonakala sengathi udayi udlule olwelwesini uyi-molecule eluhlaza okwesibhakabhaka. Ukuhlola kukhombisa okuhlukile. Isimo esiluhlaza okwesibhakabhaka asiweli kalula. Okuwelayo yisimo esingenambala, kanti umbala oluhlaza okwesibhakabhaka owubona ngaphakathi wakheka khona ngaphakathi, ngemva kokufika.

Lokhu kuphenduka kwencazelo kubalulekile ngoba kunquma ukuthi ukudayeka kungakutshelani nokuthi yini okungenakukutshela yona. Izinhlayiyana eziluhlaza okwesibhakabhaka zibonisa udayi owenziwe i-oxidation kabusha futhi wavalelwa kuma-organelle. Azibonisi lonke inani likadayi eselini, azibonisi ingxenye ereduksiwe, futhi azilinganisi umphumela webhayoloji. Ukuze ubone ukuthi kungani, landela lezi zinyathelo ezintathu: ukuredukswa ebusweni, ukusabalala kwesimo esireduksiwe, nokwenziwa i-oxidation kabusha nokuvaleleka ngaphakathi.

Lezi zimo ezimbili ziziphatha njengama-molecule ahlukene

I-methylene blue eyenziwe i-oxidation iwuhlelo lwamasongo oluyisicaba oluneshaji ephozithivu. Iyancibilika emanzini, imunca ukukhanya kakhulu endaweni ephakathi kuka-600 no-700 nanometers, futhi ibonakala iluhlaza okwesibhakabhaka. Iphuzu elibalulekile yishaji. I-molecule eneshaji nehehwa amanzi ayidluli kalula olwelwesini lwama-lipid, ngakho inkulumo enembayo emibhalweni yesayensi ithi ayikwazi ukudlula olwelwesini kalula, hhayi ukuthi ayikwazi nhlobo ukudlula.

I-methylene blue ereduksiwe, ebizwa nge-leucomethylene blue, ayinambala, ayinashaji, futhi iyancibilika emafutheni. Uma ususa ishaji, ulwelwesi alusebenzi njengodonga. I-molecule ereduksiwe isabalala inqamule kalula, futhi lapho isingaphakathi kwengxenye ekhuthaza i-oxidation kakhulu, ingalahlekelwa ama-electron futhi ibuyele esimweni esiluhlaza okwesibhakabhaka, esineshaji, esivaleleke ngaphakathi. Ngakho ikhemistri ye-redox kadayi iphinde ibe yindlela ethuthwa ngayo. Shintsha inani lama-electron bese ushintsha nokukwazi kwayo ukudlula olwelwesini.

Ama-electron esinyathelo sokuqala avela eselini uqobo. Amaseli ezilwane ezincelisayo athutha ama-electron enqamula ulwelwesi lwe-plasma, ehambisa amandla okureduksa avela kubanikeli abangaphakathi kweseli aye kubamukeli abasebusweni. Lo msebenzi owenzeka unqamule ulwelwesi lwe-plasma ungumsebenzi ojwayelekile weseli, otholakala ezinhlotsheni eziningi zamaseli. I-reductase esebusweni be-endothelium esebenza ngodayi be-thiazine ifana nezinye ngesici esisodwa esibalulekile: iyaqhubeka nokusebenza lapho kukhona i-cyanide ne-azide ngemithamo emisa izinyathelo ezilandelayo. Lokho kwehlukana kuyiphuzu eliyisisekelo layo yonke le ncazelo.

Ukuhlukaniseka kwaqala, futhi kwacishe kwachaza ukumuncwa

Ngo-1929, uMarian Irwin e-Rockefeller Institute wabuza umbuzo olula. Mhlawumbe ukungena kukadayi kumane kuwukuhlukaniseka kwawo phakathi kwamanzi nezingqimba zeseli ezinamafutha, futhi ungqimba lwe-chloroform lungamela lezo zingqimba ezinamafutha lapho kuhlolwa elabhorethri. Izifundo zakhe zokungena ezisebenzisa i-spectrophotometry zazixukuza izixazululo zikadayi ezisekelwe emanzini kanye ne-chloroform, ziqhathanise lokho okwangena esigabeni se-organic nalokho okwangena kumaseli aphilayo olwelwe.

Imiphumela emibili yalowo msebenzi isafanele ukunakwa. Okokuqala, izixazululo ze-methylene blue ezazithengiswa zaziqukethe i-trimethyl thionine, manje ebizwa nge-azure B, futhi lokho kungcola kwakungena ngokushesha kune-methylene blue uqobo, ikakhulukazi ku-pH ene-alkaline lapho kubusa isimo se-free base esincibilika kuma-lipid. Okunye okwakubonakala kuwukungena kwe-methylene blue empeleni kwakuwukungena okukhethayo kwe-azure B. Okwesibili, i-pH yayinquma umphumela ngokunquma isimo se-ionization, futhi amaseli alimele ayengenisa udayi omningi kakhulu kunalawo ayengalimele. Ama-coefficient okuhlukaniseka nesimo seshaji kwakulawula lokho okwakumuncwa uhlelo lokuhlola olwenziwe ngumuntu nalokho okwakumuncwa iseli eliphilayo. Ukufana phakathi kwalezi zinhlelo ezimbili kwasekela umqondo wokuthi kunezingqimba ezingasekelwe emanzini emngceleni weseli.

Le modeli yayiwabona kusengaphambili amandla ama-lipid ne-ionization, kodwa yayingakwazi ukuhlukanisa udayi ohlukaniseka ungashintshile kudayi oguqulwa ngokwekhemistri ebusweni, owelela ukulesinye isimo, bese uguqulwa ubuyele esimweni sawo ngaphakathi. Lokho kwehlukanisa kwakudinga olunye uhlobo lokuhlola, olwenziwa eminyakeni engamashumi ayisikhombisa kamuva ku-endothelium yamaphaphu.

Ukuredukswa ngaphandle, ukuvaleleka ngaphakathi

UMerker nozakwabo basebenza ngamaseli e-endothelium emithambo yamaphaphu ezinkomo ayekhuliswe elabhorethri, base bephakamisa ukulandelana kwezinyathelo ezintathu: udayi owenziwe i-oxidation uyaredukswa ebusweni beseli ube yisimo sawo esingenambala esincibilika emafutheni, isimo esireduksiwe sisabalalela ngaphakathi, bese ukwenziwa i-oxidation kabusha ngaphakathi kweseli kubuyisela isimo esenziwe i-oxidation esingakwazi ukudlula olwelwesini, esibe sesinqwabelana. Ucwaningo lwabo lokumuncwa kwe-thiazine yi-endothelium lwabe seluhlola lokho kulandelana ngokuzama ukukuphazamisa ezindaweni ezithile.

Ithuluzi lokuqala kwakuyi-ferricyanide, umamukeli wama-electron ongakwazi ukungena eselini. Lapho ama-enzyme asebusweni ereduksa udayi oluhlaza okwesibhakabhaka awenze ube yisimo esingenambala ngaphandle kweseli, i-ferricyanide ingaphinde ithathe lawo ma-electron, ibuyisele udayi oluhlaza okwesibhakabhaka oketshezini lokukhulisela amaseli ngaphambi kokuba welele ngaphakathi. Uma nje i-ferricyanide yayikhona ngobuningi obungaphezu kobudingeka (udayi ongu-10 micromolar uma kuqhathaniswa ne-ferricyanide engu-50 kuya ku-500 micromolar), ukumuncwa kukadayi kwakucishe kume, futhi kwaqhubeka ngesivinini sakho esivamile kuphela ngemva kokuba i-ferricyanide isiphelile. Izilinganiso zezivinini zokuphendula zaveza incazelo efanayo ngenye indlela. I-ferricyanide yayiphela ngesivinini esicishe singashintshi, okuhambisana nokugeleza okuzinzile kokuredukswa ebusweni okunikeza ama-electron kumlamuli ongasetshenziswa kabusha, kuyilapho udayi ongaphandle kweseli wawuphela ngendlela ye-exponential njengoba inani lawo lalincipha. Ukugeleza okungaguquki kanye nenani elinciphayo kusho ukuthi isignali ye-ferricyanide ibonisa ukuredukswa okuqhubekayo, hhayi ama-molecule kadayi aphuma esixazululweni.

Ithuluzi lesibili lasusa ngokuphelele isinyathelo sokuwela ulwelwesi. Iqembu laxhumanisa i-toluidine blue O, isihlobo esiseduze se-thiazine, neketango elikhulu le-polyacrylamide elalilikhulu kakhulu ukuba lingene eselini kunoma yisiphi isimo se-oxidation. Amaseli ayesawureduksa udayi oxhunyiwe. Ngakho ukuredukswa akudingi ukufinyelela ngaphakathi kweseli. Uhlelo olwenza lo msebenzi lusebusweni noma luxhumene nabo ngogesi.

Kwabe sekulandela ukwehlukanisa okunikeza iphepha isihloko salo. I-cyanide ne-azide ezingu-2 millimolar zacindezela kakhulu ukunqwabelana kukadayi, futhi lapho kubukwa ngesibonakhulu, izinhlayiyana zangaphakathi eziluhlaza okwesibhakabhaka okumnyama nezinsomi, ezivame ukuzungeza i-nucleus, zacishe zanyamalala. Nokho, akukho nesisodwa salezi zivimbeli esanciphisa isivinini sokuredukswa ngaphandle kweseli: umjikelezo we-ferricyanide waqhubeka unganciphanga, futhi i-polymer engakwazi ukungena nayo yayisaredukswa. Ukuvinjwa kwakusesinyathelweni esilandelayo. I-cyanide ne-azide zazimisa ukwenziwa i-oxidation kabusha nokugcinwa kukadayi ezingxenyeni zangaphakathi kweseli, hhayi ukuredukswa ebusweni. Ukuhlola kokulawula ukuthi amaseli ayesaphila kwayisekela le ncazelo, ngoba amaseli agcina i-lactate dehydrogenase, i-enzyme ewuphawu lwe-cytosol yawo, phakathi nalokhu kwelashwa kokuhlola. Ngakho ukulahleka kokumuncwa kwakungabangelwa nje ubuthi noma ukuqhekeka kolwelwesi.

Isixwayiso esisodwa saleli phepha sisasebenza. Izinhlayiyana eziluhlaza okwesibhakabhaka zazizungeze i-nucleus kodwa zingekho phakathi kwayo, okuhambisana ne-oxidation eyenzeka kuma-organelle angaphakathi kweseli, kodwa ucwaningo aluzange lukhombe ukuthi yimaphi ama-organelle. Amaphethini afanayo kwezinye izinhlobo zamaseli ayebizwe ngokuthi awe-lysosome, kusekelwe ebufakazini obuncane. Thatha ukuvaleleka njengokuqinisekisiwe, kodwa indawo okwenzeka kuyo njengengakaqinisekiswa. Abafundi abalandela ukuthi ama-electron aya kuphi ngemva kwalokho bangaqhubekela kokuthi ukuthuthwa kwama-electron nokuphathwa kwe-redox kuma-mitochondria kanye nesithombe esibanzi sokumuncwa nokusatshalaliswa ngokwendlela yokungena.

Ukudayeka akusilo inani elifinyelela ezicutshini

Ucwaningo lwesithathu lubonisa okwenzekayo lapho le ndlela yokumuncwa iqhathaniswa nesilinganiso somsebenzi webhayoloji. UScott nozakwabo bathola ukuthi i-methyl beta cyclodextrin, ushukela onesakhiwo esifana nendandatho, ibopha i-methylene blue ngokuqondile, nge-constant yokuhlangana ecishe ibe ngu-310 per molar ye-complex lapho udayi uvaleleke ngaphakathi kwendandatho, uma kuqhathaniswa necishe ibe ngu-5846 per molar yokuhlangana kwama-molecule amabili kadayi. Kuma-fibroblast e-L929, lokhu kubopha kwavimba kokubili ukudayeka kwamaseli nokugqugquzelwa kokumuncwa kwe-glucose: ukugcina amaseli ne-cyclodextrin ngaphambi kokufakwa kukadayi kwavimbela ukudayeka okuluhlaza okwesibhakabhaka, futhi ukuyifaka ngemva kwalokho kwasheshisa ukususwa kombala. Njengoba isignali yokukhanya eluhlaza okwesibhakabhaka yayiphela kumaseli, ukuthuthwa kwe-glucose okwakugqugquzelwe nakho kwakuncipha kuhambisana nayo eduze.

Ababhali bachaza lokhu kuhlobana njengokusekela ukusebenzisana okuqondile phakathi kukadayi nephrotheni esendleleni yokwenziwa komthuthi we-glucose asebenze, kunendlela yengcindezi ye-oxidation ehlala isikhathi eside. Leso siphetho siyafaneleka, kodwa sinemingcele. Ukuhlola akuyikhombi iphrotheni, akubonisi ukubopha kumthuthi uqobo, futhi ukuhlobana phakathi kokususwa kombala nokulahleka komphumela akukwazi ukukhipha zonke izindlela ezilawulwa yi-redox.

Isifundo esihlala sibalulekile simayelana nokulinganisa. Ukudayeka okubonwa ngokukhanya kubonisa udayi obonakalayo, owenziwe i-oxidation, ohlobene neseli. Akuyiboni nhlobo ingxenye ereduksiwe engenambala, ngakho iseli eliphaphathekile lingase libe nodayi, futhi iseli elidayeke kakhulu libonisa udayi owenziwe i-oxidation ovalelekile, hhayi lonke inani elifinyelele ezicutshini noma ubukhulu bomphumela. Isixwayiso esifanayo siyasebenza nasezingeni elikhulu: ukuqhathanisa ukudayeka ezinhlotsheni zamaseli, noma ukuthatha isiqeshana sezicubu esidayeke saba mnyama njengobufakazi bokuthi kufinyelele udayi omningi, kuphinda iphutha lokuqala lokubuka amaseli esitsheni. Ukumuncwa kuwumjikelezo wokuredukswa, ukusabalala, nokwenziwa i-oxidation kabusha, futhi noma yisiphi isithombe sesikhashana sesimo esiluhlaza okwesibhakabhaka sibona ingxenye eyodwa kuphela yawo. Imiphumela yalokhu ekudayeni nasekuphatheni elabhorethri nasekuchazeni izimangalo ngomthamo nenani elifinyelela ezicutshini ilandela ngokuqondile.