Inyandiko
Ubururu bwa methylene nk'ikirwanya n'igiteza okisidasiyo: ni iki gihindura igisubizo?
Tekereza laboratwari ebyiri zipimye irangi rimwe ry'ubururu zikagaragaza ibisubizo bihabanye. Muri iya mbere, mitokondiriya zatandukanyijwe n'uturemangingo tw'ubwonko zihumeka neza kurushaho kandi zigakora ATP nyinshi. Muri iya kabiri, izo mitokondiriya zateguwe kimwe zirekura perogiside ya hidurojeni nyinshi cyane kurushaho. Raporo zombi ni ukuri. Zisobanura uruziga rumwe rw'imikorere rurebewe ku mpande ebyiri, kandi urujijo rutangira iyo abasomyi bafashe uruhande rumwe nk'aho ari rwo rusobanura byose.
Ikosa ni ukubaza izina rikwiriye guhabwa iyo molekile. Ubururu bwa methylene ni umuyoboro uhererekanya elegitoroni, nk'uko ikarita y'ibyo bukoraho mu binyabuzima by'uturemangingo ibigaragaza mu rwego rwagutse. Irangi ryakorewe okisidasiyo ryakira elegitoroni rigahinduka leucoMB itagira ibara. LeucoMB ihererekanya izo elegitoroni ikongera kuba ubururu. Ibyo ubona biterwa n'utanga elegitoroni, uzakira, n'ubushobozi bw'urwo rusobe bwo gukuraho perogiside ya hidurojeni ikorwa muri iyo nzira. Ikibazo gikwiye kubazwa si ukumenya niba irangi rirwanya okisidasiyo. Ni ukumenya icyo imimerere irimo yemerera uwo muyoboro gukora.
Uruziga rutanga izo mpande zombi
Mu mwijima, uruziga rw'ibanze ni rugufi. NADH, NADPH, cyangwa abatwara elegitoroni mu ruhererekane rw'ihumeka bigabanya irangi. Irangi ryagabanyijwe riba rifite inzira zitandukanye zihatanira elegitoroni. Rishobora kuziha sitokorome c maze rigafasha gukomeza urujya n'uruza rwazo runyuze iruhande rw'urusobe rwangiritse; ni yo mpamvu ihumeka n'itandukaniro ry'ingufu z'amashanyarazi ku gahu byongera gukora igice iyo urusobe I cyangwa III rwahagaritswe. Cyangwa rishobora guha elegitoroni ogisijeni mu buryo butaziguye, bigasubiza irangi mu miterere y'ubururu kandi bigakora perogiside ya hidurojeni. Kubera ko irangi ryongera kuboneka, ingano nto ishobora gusubiramo urwo ruziga inshuro nyinshi, ikomeza gukoresha ubushobozi bwo gutanga elegitoroni kandi ikomeza gukora perogiside.
Andi mashami abiri ahindura rwose ibyo bikorwa bya shimi. Umuringa cyangwa icyuma bitabohewe bihindura iyo perogiside ishobora gukwirakwira mo ibiteza okisidasiyo byangiza cyane kurushaho aho biri, binyuze mu bikorwa bya shimi byo mu bwoko bwa Fenton. Urumuri rutukura rufungura ishami ritandukanye ry'ibikorwa bya shimi biterwa n'urumuri, aho irangi ryongerewe ingufu rihererekanya izo ngufu kuri ogisijeni rigakora ogisijeni yo mu mimerere ya singlet, isobanurwa birambuye mu nyandiko isobanura ibikorwa bya shimi biterwa n'urumuri byo mu bwoko I na II. Uruziga rwa okisidasiyo n'igabanywa mu mwijima, iyangirika ryongerewe n'ibyuma, n'iyangirika riterwa n'urumuri ni uburyo butatu butandukanye buhurira gusa ku molekile imwe butangiriraho.
Imbonerahamwe ihuza imimerere n'ibisubizo
Imbonerahamwe ikurikira ni yo ngirakamaro yo kubika. Buri murongo ugaragaza ikintu kimwe gihinduka, icyerekezo gisunikira igisubizo, n'igerageza rishingirwaho. Icyiza bivuga igipimo kigaragaza uburinzi cyangwa imikorere myiza kurushaho. Ikibi bivuga ibiteza okisidasiyo byinshi kurushaho, ishira ry'ibigize ubwirinzi ryiyongereye, cyangwa iyangirika ryinshi kurushaho.
| Imimerere | Icyerekezo cy'igisubizo | Icyo igerageza ryagaragaje |
|---|---|---|
| Ubwinshi buke, 0.1 kugeza kuri 1 uM, mitokondiriya zatandukanyijwe n'uturemangingo | Imikorere myiza mu gutanga ingufu hamwe na perogiside yiyongereye | 0.1 uM yatumye mitokondiriya zo mu mutima w'imbeba nzima n'izirwaye diyabete zikoresha ogisijeni neza kurushaho; 100 nM kugeza kuri 1 uM byagaruye igice cy'ikorwa rya ATP, itandukaniro ry'ingufu z'amashanyarazi ku gahu, n'iyinjizwa rya kalisiyumu muri mitokondiriya z'ubwonko zari zahagaritswe, mu gihe irekurwa rya perogiside ryiyongereye mu mimerere yose |
| Ubwinshi buri hejuru, burenze 5 uM, uturemangingo twimwe glucose | Ikimenyetso kibi cy'ibiteza okisidasiyo | Uturemangingo tw'uruhu rw'imbere mu miyoboro y'amaraso twakoreye okisidasiyo ikimenyetso gipima ROS muri rusange kandi dutakaza glutathione iri mu miterere yagabanyijwe hejuru ya 5 uM igihe glucose itari ihari; kongeramo glucose byabujije byombi |
| Ibikoresho fatizo by'urusobe I (glutamate hamwe na malate) | Perogiside nyinshi kurushaho | Ubushakashatsi kuri mitokondiriya z'ubwonko n'iz'umutima bwombi bwabonye irekurwa rya perogiside ryiyongereye hamwe n'ibikoresho fatizo bifitanye isano na NADH |
| Succinate hamwe na rotenone, mitokondiriya z'umutima, 0.1 uM | Perogiside nke muri ubwo buryo bw'igerageza | Ni cyo gipimo cya perogiside cyonyine muri iri tsinda cyagaragaje neza kurwanya okisidasiyo; zirikana ko uburyo bw'igerageza bwarimo rotenone kandi bwakoresheje ingirabuzima itandukanye, bityo ibikoresho fatizo byonyine ntibisobanura icyo gisubizo |
| Urumuri rutukura, 20 uM hamwe na 630 nm | Iyangirika ribi rya DNA | Nta kwangirika gukomeye kwa DNA ya mitokondiriya kwabonetse mu mwijima kuri 20 uM; ubwinshi bumwe hamwe n'urumuri rutukura bwangije buri gice cyapimwe |
| Ubwinshi buri hejuru cyane mu mwijima, 100 uM | Iyangirika ribi rya DNA ryibasira ibice byihariye | Iyangirika rya DNA ya mitokondiriya ryibasira urukurikirane rukungahaye kuri purine, ari impinduka ikomeye ugereranyije n'ikimenyetso cya perogiside ku rugero rwa nanomolar |
| Umuringa cyangwa icyuma hamwe na NADH, DNA idafite uturemangingo | Iyangirika ribi riterwa na okisidasiyo | Umuringa wayoboye iyangirika ku rukurikirane rwa p53 rukunze kwangirika; icyuma EDTA cyateje iyangirika ahantu henshi; catalase n'ibinyabutabire bibopha ibyuma byahagaritse inzira bijyanye; guanine yakorewe okisidasiyo yariyongereye |
| Glucose ihari, uturemangingo twuzuye | Kugabanya imihangayiko mu buryo burinda nubwo uruziga rwihuta | Glucose yongereye igabanywa ry'irangi ariko igabanya imihangayiko isigara muri rusange, bihuje n'itangwa rya NADPH binyuze mu nzira ya pentose phosphate kugira ngo ibirwanya okisidasiyo byongere gukoreshwa |
| Uturemangingo twahawe ascorbate nyinshi | Bivanze: ascorbate yakoreshejwe, ikimenyetso cy'igipimo kiragabanywa | Irangi ryagiye rikora okisidasiyo kuri ascorbate yo mu turemangingo nubwo glucose yari ihari, ariko rigabanya igice cya okisidasiyo y'ikimenyetso gipima; ibigize ubwirinzi ni byo byatanze ikiguzi |
| Inyamaswa zavuwe mbere yo kugerageza rotenone, irangi ritanzwe mbere | Igisubizo cyiza mu ngirabuzima | Gutanga irangi mbere byagabanyije iyangirika rya DNA ya mitokondiriya ryatewe na rotenone mu gice cyo hagati cy'ubwonko bw'imbeba, nubwo ryongereye perogiside muri mitokondiriya zatandukanyijwe n'uturemangingo |
Imiterere igaragara muri iyo mirongo ni yo ngingo y'ingenzi. Ikorwa rya perogiside n'uburinzi bw'ibinyabuzima ni ibipimo bibiri bitandukanye. Uburyo bwakoreshejwe bushobora gutanga igisubizo kibi ku cya mbere n'icyiza ku cya kabiri icyarimwe.
Impamvu ingano imwe itanga ibisubizo bitandukanye
Ubwinshi bugena ubushobozi bwo gutwara elegitoroni, ntibugena aho bizagarukira. Irekurwa rya perogiside muri mitokondiriya z'ubwonko ryiyongereye ku buryo bushobora gupimwa guhera kuri 50 nM kujyana hejuru mu bushakashatsi kuri mitokondiriya z'ubwonko zuzuye, mu gihe iyangirika rigaragara rya DNA ya mitokondiriya ryasabaga 100 uM mu mwijima. Icyo ni ikinyuranyo kingana hafi n'inshuro ibihumbi bibiri hagati y'ikimenyetso cya mbere n'ubushobozi bwo kwangiza ibikoresho by'irondakoko, ariko si intera yerekana umutekano. Ibyapimwe, ibice byakorewemo n'igihe byamaze bihura n'irangi biratandukanye, bityo imibare igaragaza ibintu bitandukanye aho kuba ingingo zo ku murongo umwe. Ikiganiro ku isano y'ingano n'igisubizo gishyira icyo kinyuranyo hagati y'ikimenyetso gito n'iyangirika rikomeye mu rwego rwagutse rwa hormesis.
Ibikoresho fatizo bigena aho elegitoroni zinjirira. Ibikomoka ku ntungamubiri bifitanye isano na NADH biha irangi ubushobozi bwinshi bwo gutanga elegitoroni, haba mu nzira y'ingirakamaro izenguruka ahangiritse no mu gikorwa cya shimi na ogisijeni gitwara ubushobozi nta nyungu. Incamake ikunze gusubirwamo ivuga ko succinate ituma irangi rirwanya okisidasiyo naho glutamate igatuma riteza okisidasiyo isobanura amakuru ibirenze ibyo yerekana, kuko imimerere ya succinate yakoreshejwe mu gupima perogiside mu bushakashatsi bw'umutima yarimo na rotenone kandi yakoresheje ingirabuzima n'ingano bitandukanye n'ubushakashatsi bw'ubwonko bwabonye perogiside yiyongereye ku bikoresho fatizo byose no mu mimerere yose y'ihumeka.
Urumuri ruhindura uburyo bw'imikorere, si ubukana bwabwo gusa. Itandukaniro risobanutse kurusha ayandi muri iri tsinda ni uko 20 uM mu mwijima nta cyo yakoze cyashoboraga kugaragara ku bice bya DNA ya mitokondiriya, naho 20 uM munsi y'urumuri rutukura ikabyangiza byose. Ugereranya igerageza rikorwa mu rumuri n'irikorerwa mu mwijima aba agereranya ibikorwa bya shimi biterwa n'urumuri n'uruziga rwa okisidasiyo n'igabanywa.
Ibyuma bihindura igiteza okisidasiyo. Iyo nta byuma bihari, uruziga rw'irangi rwo mu mwijima rukora perogiside, molekile ishobora gukwirakwira kandi uturemangingo dukoresha no nk'ikimenyetso. Iyo hari umuringa cyangwa icyuma bishobora gukoreshwa, irangi ryagabanyijwe na NADH ritanga elegitoroni zigabanya icyuma, maze icyuma cyagabanyijwe kigahindura perogiside mo ibinyabutabire byo mu bwoko bwa hydroxyl cyangwa perogiside y'umuringa iruhande rwa DNA. Ni muri ubwo buryo ubushakashatsi butarimo uturemangingo bwakoresheje NADH na iyoni z'ibyuma bwateje iyangirika rya DNA ryibasira ahantu hakunze kwangirika n'irikwiye ahantu henshi, buhereye ku irangi rimwe. Uburyo ibyuma bigenzurwa mu gice kirimo icyo gikorwa, atari irangi ryonyine, ni bwo bugena niba iri shami rifite uruhare.
Uko ibikoresho bitanga ingufu bihagaze bigena niba akaremangingo gashobora kwishyura ikiguzi. Mu turemangingo tw'uruhu rw'imbere mu miyoboro y'amaraso twahuye n'irangi rya 2 kugeza kuri 20 uM, gukuraho glucose byagaragaje ikiguzi cy'ibiteza okisidasiyo, naho gutanga glucose bikagikuraho, nubwo glucose yanihutishije igabanywa ry'irangi. Uruziga rwihuta rufite ubwirinzi bwahawe ibyo bukenera rurusha uruziga rutinda rufite ubwirinzi bwashize. Fata nk'ibidasuzumwe mu buryo bwuzuye amagambo yose avuga ibiteza okisidasiyo atagaragaza uko glucose cyangwa NADPH bihagaze.
Ubwoko bw'ingirabuzima bugena ibikoresho by'imikorere bihari. Uturemangingo tw'uruhu rw'imbere mu miyoboro y'amaraso twongera gukora NADPH binyuze mu ihinduramatwara rya glucose kandi dufite ibigega by'ibirwanya okisidasiyo muri sitozole. Mitokondiriya zatandukanyijwe n'uturemangingo nta na kimwe muri ibyo zifite. DNA yatunganyijwe ngo isigarenyine nta n'uburyo bwo kwisana ifite. Igisubizo cyabonetse mu buryo bumwe bwo gutegura ibigeragezwa ntigitanga ubushobozi bwinshi bwo guteganya ibizaba mu bundi, ari na yo mpamvu inyandiko iteganyijwe ku bisubizo byihariye by'ingirabuzima izakenera gutandukanya izo nsobe.
Gupima mu buryo butaziguye si ubwirinzi bukurikiraho
Inyandiko nyinshi zihuza ibyiciro bibiri amagerageza atandukanya. Icyiciro kimwe kibaza ingano y'ibiteza okisidasiyo byagaragaye. Ikindi kikabaza uko akaremangingo kabyitwayemo.
Ibizamini bya perogiside byo mu bwoko bwa Amplex ni byo byegereye cyane icyiciro cya mbere, kandi na byo bitanga igipimo cy'urujya n'uruza rusigara: ibikozwe hakuwemo ibisenywe n'ibisohowe. Ubushakashatsi kuri mitokondiriya z'ubwonko bwabonye impinduka ku mpande zombi: perogiside nyinshi yarakozwe kandi gukuraho ingano ya perogiside yongerewe icyarimwe byaratindaga. Ibipimo byo mu byiciro bikurikiraho birimo okisidasiyo ya glutathione, ikoreshwa rya ascorbate, guanine yakorewe okisidasiyo, n'iyangirika rya DNA ribuza polymerase gukora. Buri ntambwe yongeramo ibikorwa by'ibinyabuzima hagati y'igiteza okisidasiyo n'igisubizo gipimwe.
Enzime zirwanya okisidasiyo ziyobowe na Nrf2 n'ikorwa rya mitokondiriya nshya biri mu cyiciro cya kabiri. Ni gahunda zo kwihanganira impinduka zishobora gutangizwa n'izamuka rito kandi ry'igihe gito rya perogiside; abanditsi b'ubushakashatsi ku kurinda mitokondiriya z'ubwonko batanga neza icyo gitekerezo cy'imihangayiko yoroheje itangiza ubwirinzi, banagaragaza ko uruhererekane rw'impamvu n'ingaruka runyura kuri Nrf2 rushingiye ku bushakashatsi bwabanje aho kuba gihamya yuzuye batanga bo ubwabo. Uburinzi buza nyuma y'amasaha binyuze muri poroteyine nshya ntibuvuga ko igikorwa cya shimi cyabutangije cyarwanyaga okisidasiyo. Bivuga ko igikorwa gito cyateje okisidasiyo cyatumye haboneka ubwirinzi bunini kurushaho. Ibyo kwitondera mu gusoma amagambo nk'ayo, harimo imbibi z'ibizamini n'itandukaniro ry'ibitegurwa mu magerageza, ni byo inyobora yo gusoma ubushakashatsi ku bururu bwa methylene ivugaho.
Impamvu ibizamini bitanga ibisubizo bitandukanye
Ikimenyetso gipima muri rusange nka dihydrofluorescein kigaragaza okisidasiyo yagikorewe mu buryo bwagutse, si ubwinshi bwa perogiside. Gishingira ku bikorwa bya shimi bya peroxidase na heme kandi gishobora kutabona izamuka rya perogiside ribonwa n'ikizamini cya Amplex cyagereranyijwe n'ibipimo bizwi. Ubushakashatsi kuri mitokondiriya z'ubwonko bwabonye perogiside yariyongereye cyane nta kimenyetso cya superoxide kiyiherekeje, bikaba ari umuburo wo kwirinda gusubiramo umwanzuro uwo ari wo wose wo kurwanya okisidasiyo ushingiye ku irangi rimwe gusa. Guhura kw'imirongo y'urumuri ni ikibazo gikwiye kugenzurwa, kuko irangi ryinjiza urumuri rugaragara hafi y'imirongo isanzwe ikoreshwa mu kurisembura no gupima urumuri risohora; ariko ubushakashatsi bwitondewe bwagereranyije ibipimo na perogiside ifite ubwinshi buzwi, bugabanya igihe cyo guhura n'urumuri rusembura hagaragara impinduka nto ku kimenyetso, kandi bwemeza ko gukuraho perogiside byatindaga bukoresheje elekitorode itandukanye. Kwivanga mu gipimo ni ikintu kigomba kugenzurwa, si impamvu ihita ituma igisubizo cyangwa.
Igisubizo cya kalisiyumu kigaragaza ko na cyo gisaba ubwo bwitonzi mu gusobanura. Irangi ryakoreshejwe mu gihe gito ntiryahinduye ingano yose ya kalisiyumu mbere y'uko agahu gatangira guhindura uburyo gatambutsa ibintu mu bushakashatsi bw'umutima, ariko ryongereye umuvuduko w'iyinjizwa rya kalisiyumu muri mitokondiriya z'ubwonko zari zahagaritswe mu bushakashatsi kuri mitokondiriya z'umutima bwibanze kuri diyabete. Ibipimwa bitandukanye, insobe zitandukanye, nta kuvuguruzanya.
Urutonde rw'ibyo kugenzura mbere yo kwizera umwanzuro
Fata buri mwanzuro wo kurwanya cyangwa guteza okisidasiyo nka raporo ku rusobe runaka, maze ubaze ibibazo bitanu. Ni ku buhe bwinshi, kandi mu kihe gice? Ni uwuhe utanga elegitoroni n'uwuhe uzakira uhatanira kuzakira? Hari urumuri cyangwa umwijima, kandi ni ku buhe burebure bw'umuraba no ku yihe ngano y'urumuri? Ni ibihe byuma biboneka, kandi ni ibihe bikoresho bitanga ingufu n'ibigega by'ibirwanya okisidasiyo byahawe ibyo bikenera? Kandi ni ikihe kizamini cyakoreshejwe, gipima urujya n'uruza rw'ibiteza okisidasiyo, iyangirika, cyangwa igisubizo cyo kwihanganira impinduka? Hindura igisubizo icyo ari cyo cyose muri ibyo, maze molekile imwe ishobora kuva mu cyiciro kirinda ikajya mu cyangiza muri iyo mbonerahamwe, nta kwivuguruza na gato kurimo.