Inqaku
I-methylene blue ne-NAD+/NADH: ukutolika ulungelelwano lwe-redox kwiiseli
Iingxelo nge-methylene blue ne-NAD+ zidla ngokudibanisa amabango amathathu ahlukeneyo abe linye. Ibango lokuqala lelokuba umlinganiselo we-NAD+ xa ithelekiswa ne-NADH uye wasondela kwimeko ye-oxidation. Elesibini lelokuba iseli ine-NAD iyonke eninzi ngakumbi. Elesithathu lelokuba ukuveliswa kwamandla kubuyele kwimeko efanelekileyo. La mabango avakala njengebali elinye lokubuyisela imetabolism. Kwiimvavanyo, ahlala ehlukana, yaye iziphumo ezinomdla zezo kanye apho angangqinelani khona.
Oku kudideka kuyaqondakala kuba ezi zixa zintathu zisebenzisa isigama esifanayo. I-NAD+ yamkela ii-electron kwiintshukumo zemetabolism ize ibe yi-NADH, emva koko i-mitochondria yenza i-oxidation ye-NADH iyibuyisele kwi-NAD+ kwikhompleksi I, ize isebenzise amandla akhululweyo ukwenza i-ATP. Inkcazelo epheleleyo yale ndlela yee-electron ifumaneka kwinkcazelo yokuthuthwa kwee-electron kwi-mitochondria, yaye icala lamandla likwi-ATP nakwimetabolism yamandla. Kodwa umlinganiselo novimba zizinto ezahlukeneyo. Umlinganiselo uchaza indlela abathuthi abakhoyo abasasazwe ngayo phakathi kweemeko zokuthwala umthwalo nezokungathwali mthwalo. Uvimba uchaza ukuba zingaphi iimolekyuli zabathuthi ezikhoyo zizonke. Umlinganiselo ongcono kunye novimba ongatshintshanga uthetha ukwabiwa ngokutsha, kungekhona ukuveliswa.
Amacandelo amabini, izalathisi ezibini
Kukho omnye umahluko obangela ukutolika okungachananga okungaqapheleki lula. Oovimba be-NAD abakwi-cytosol nabakwi-mitochondria bohlulwe ubukhulu becala yinwebu yangaphakathi ye-mitochondria, ngoko icandelo ngalinye linokuba kwimeko ethe kratya ye-oxidation okanye ye-reduction ngokuzimeleyo. Inani elinye leseli iyonke liyawufihla lo mahluko.
Uphando lwesibindi lwenza ukuba ukwahlukana kwala macandelo kulinganiseke. Ulungelelwano phakathi kwe-lactate ne-pyruvate lubonisa umlinganiselo we-NAD+ xa ithelekiswa ne-NADH kwi-cytosol, kuba i-lactate dehydrogenase idibanisa ezo zibini zezinto. Ulungelelwano phakathi kwe-3-hydroxybutyrate ne-acetoacetate lubonisa umlinganiselo okwi-mitochondria ngendlela efanayo yokudibanisa. Xa zombini ezi zibini zilinganiswa kwizicubu ezibanjwe zaza zakhenkceziswa ngokukhawuleza, njengakwi-sifundo sokondla iimpuku nge-ethanol ixesha elide, isiphumo zizilinganiso ezibini ze-redox ezivela kwisibindi esinye, yaye ikhompawundi inokutshintsha esinye ngaphezu kwesinye.
I-methylene blue isebenza kule nkqubo njengomthuthi wee-electron kunokuba ibe sisibaso. Yamkela ii-electron kwi-NADH kufutshane nekhompleksi I, ibe kwimeko ye-reduction, ize izidlulisele phambili kubathuthi abanjenge-cytochrome c. Isiphumo esipheleleyo yi-oxidation ye-NADH ngaphandle kokudlula kuyo yonke indlela eqhelekileyo. Loo ndlela yokusebenza ichaza umtsalane wayo nomda wayo: inokunciphisa ukuxinana okubangelwa yimeko ye-reduction, kodwa ayakhi ngokutsha ikhompleksi eyonakeleyo okanye ivelise iimolekyuli ezintsha ze-NAD.
Izifundo ezihlanu, indlela enye yeziphumo ezahlukeneyo
Itheyibhile engezantsi ibeka izifundo ezihlanu ngokwezicubu, isiphumo se-redox esilinganisiweyo, isiphumo samandla esilinganisiweyo, noko kubuyele kwimeko efanelekileyo ngokwenene. Funda iikholam ezimbini zokugqibela kunye. Oko kudityaniswa kungumongo weli nqaku.
| Izicubu nomonakalo owenziweyo | Isiphumo se-redox esilinganisiweyo nge-methylene blue | Isiphumo esilinganisiweyo samandla nokudluliselwa kwemiqondiso | Isiphumo sokusebenza |
|---|---|---|---|
| Isibindi sempuku, ukutya okune-ethanol ixesha elide | Imilinganiselo ye-NAD+/NADH kwi-cytosol nakwi-mitochondria ibuyiselwe ubukhulu becala; i-glycerol 3-phosphate ibuyiselwe kwimeko eqhelekileyo | I-ATP ayitshintshanga ngenxa ye-ethanol okanye yonyango; ukwehla okuncinci kwe-ATP ngedayi kwixesha lokulinganisa lamva | Ukungena kwamafutha akuzange kutshintshe; ii-lipid ne-triacylglycerol zahlala ziphezulu |
| Ii-hepatocyte nesibindi seempuku ezincinci ezitya ukutya okunamafutha amaninzi | Umlinganiselo we-NAD+/NADH nomxholo we-NAD+ unyukile kwiiseli nakwisibindi | I-SIRT1 inyukile, amaqela e-acetyl asuswe kwi-PGC-1alpha, i-DNA ye-mitochondria nokusetyenziswa kweoksijini kunyukile, ukuvuselelwa kwe-AMPK kuxhomekeke kwi-SIRT1 | Ukuqokelelana kwamafutha esibindini ne-steatohepatitis kunciphile |
| Intliziyo yempuku enesifo seswekile | Umlinganiselo we-NADH/NAD+ wehlile ngexesha le-oxidation ye-substrate kwi-mitochondria ehlukanisiweyo | Umsebenzi we-SIRT3 unyukile; ukufakwa kwamaqela e-acetyl kwi-lysine kwehlile kwiindawo eziyi-83 kwiiproteni eziyi-34 | Imithamo yentliziyo neqhezu legazi elikhutshwayo ziphucukile; isiphene sekhompleksi I ngokwaso asizange silungiswe |
| Iretina yeempuku ezincinci eziswele i-AIF neeseli ezamkela ukukhanya ezinyangwe nge-rotenone | Umlinganiselo we-NADH/NAD+ ubuyiselwe kwimeko eqhelekileyo kwiiseli; uxinzelelo lwe-oxidation lwehlile | Ukunqongophala kwe-ATP akuzange kulungiswe kwiiseli; iindlela zoxinzelelo lwe-mitochondria zithotyiwe | Ubukhulu beretina nezalathisi zeeseli ezamkela ukukhanya zigciniwe; ukusinda kweeseli kuphucukile |
| Ithenda ye-Achilles yomntu neyempuku, umonakalo owenziwe yi-oxidant ne-collagenase | Ulungelelwano lwe-NAD+ nemeko yemichiza ye-NAD iyonke zibuyiselwe zasondela kwezo zeqela lolawulo | I-ATP inyukile ne-ROS yehlile apho ukubuyiselwa kwenzekileyo | Izalathisi ze-matrix ziphucukile ngaphandle kwaxa ikhompleksi I ibivaliwe ngokuthe ngqo, apho imeko yemichiza yatshintshayo kodwa izicubu azaphucuka |
Apho ukulungiswa kwe-redox kungazange kubuyisele izicubu
Esona sifundo sidala kweli qela sisesona silumkiso sicacileyo. Iimpuku ezanikwa i-ethanol eyenza i-36 percent yamandla okutya zaba nemilinganiselo esezantsi ye-NAD+/NADH kwi-cytosol nakwi-mitochondria, elinganiswe ngazo zombini izibini zezalathisi, yaye i-methylene blue ekutyeni emalunga ne-42 mg nge-kg ngosuku yathintela olo tshintsho ubukhulu becala. Sekunjalo, i-triacylglycerol yesibindi yaphantse yaphindaphindeka kathathu ngexesha lokulinganisa lamva, nokuba idayi yayikhona okanye ingekho, yaye uhlolo lwezicubu lwabonisa amafutha afanayo embindini wee-lobule. Ababhali basichaza ngokuthe ngqo isigqibo esingathandekiyo: utshintsho lwe-redox oluhamba ne-oxidation ye-ethanol alulodwa olubangela isibindi esinamafutha. Umfundi othatha umlinganiselo olungisiweyo njengothetha ilungu elilungisiweyo anganika ingxelo engachananga ngeli phepha. Uyilo olupheleleyo, kuquka amaqela olawulo awayenikwa izixa zokutya ezilinganayo kunye nokuthathwa kweesampulu ezinzulwini zobusuku xa ukunxila kuphezulu, luchazwe kwisifundo sesibindi ne-ethanol.
Thelekisa oko nomsebenzi wesibindi ngokutya okunamafutha amaninzi, apho uhlobo olufanayo lotshintsho lomlinganiselo lwenzeka kunye nokuphucuka kwezicubu ngokwenene. Kwii-hepatocyte nakwisibindi seempuku ezincinci emva kokunikwa idosi ngomlomo, i-methylene blue yanyusa umlinganiselo we-NAD+/NADH, yaye ikhonkco lokudluliselwa kwemiqondiso lalandelwa inyathelo ngenyathelo: i-SIRT1 yanyuka, amaqela e-acetyl asuswa kwi-PGC-1alpha, izalathisi zokuveliswa kwe-mitochondria nokusetyenziswa kweoksijini zanyuka, kwaza kwasebenza i-AMPK, i-CPT-1 ne-PPARalpha, yaye kwaboniswa ukuba ukuvuselelwa kwe-AMPK kuxhomekeke kwi-SIRT1. Iimpuku ezincinci ezazitya ukutya okunamafutha amaninzi zaqokelela amafutha ambalwa esibindini. Inkcazelo ecetywayo yeyokuba utshintsho lwe-redox apha lwavula inkqubo yokulawula imizila yemfuza kunokuba lulungelelanise nje imeko yemichiza, njengoko kuchaziwe kwisifundo sesibindi se-SIRT1 ne-AMPK. Luhlobo olufanayo lwemilinganiselo nolwesifundo se-ethanol, kodwa isigqibo ngezicubu sichasene naso. Umahluko ukwindlela esebenza emva kolo tshintsho, hayi kumlinganiselo wodwa.
Intliziyo neretina: ii-sirtuin, ukufakwa kwamaqela e-acetyl, nokubuyiselwa ngaphandle kwe-ATP
Isifundo sentliziyo enesifo seswekile sidibanisa utshintsho lwe-redox nokufakwa kwamaqela e-acetyl kwiiproteni nge-sirtuin eyahlukileyo. I-mitochondria ekwimeko yesifo seswekile inamaqela e-acetyl agqithisileyo kwi-lysine yee-enzyme zemetabolism, nto leyo ehambelana nokungakwazi ukutshintsha lula phakathi kwee-substrate. I-methylene blue kwi-10 mg nge-kg ngosuku yanceda i-oxidation ye-NADH ngendlela exhomekeke kwidosi kuluhlu lwe-6 ukuya kwi-18 micromolar kwi-mitochondria ehlukanisiweyo, yanyusa umsebenzi we-SIRT3, yaza yanciphisa ukufakwa kwamaqela e-acetyl ngokubanzi, ngoxa imithamo yentliziyo neqhezu legazi elikhutshwayo zaphucuka nangona ukuphazamiseka okusisiseko kwekhompleksi I kwahlala kukhona. Iphepha liyicacisa indlela ezisebenza ngayo iidosi kwezinye iincwadi zophando: izixinaniso ezisezantsi zixhasa indima yomthuthi kwimeko ye-reduction, ngoxa eziphezulu zinokuthumela ii-electron kwezinye iindlela ezingavelisi nto iluncedo, ngoko isiphumo silandela i-hormesis kunokuba siqhubeke sisonyuka kwicala elinye. Uhlolo lweeproteni nemilinganiselo yentliziyo zinikwe kwisifundo sokufakwa kwamaqela e-acetyl kwintliziyo enesifo seswekile. Indlela yokujonga oku ngokoxinzelelo lwe-oxidation ifumaneka kuxinzelelo lwe-oxidation nolawulo lwe-ROS.
Isifundo seretina siwubonisa kakhulu lo mahluko. Kwiimpuku ezincinci ze-Harlequin ezinokuswela i-AIF, okuyisiphene sokudityaniswa kwekhompleksi I, i-methylene blue yagcina ubukhulu beretina, amacandelo angaphandle eeseli ezamkela ukukhanya, nezalathisi zeeseli ze-rod, ze-cone, ze-Muller nezama-ganglion. Kwiiseli ezamkela ukukhanya ze-661W ezinyangwe nge-rotenone, idayi yabuyisela umlinganiselo we-NADH xa ithelekiswa ne-NAD+ kwimeko eqhelekileyo yaza yanciphisa iintlobo zeoksijini ezisebenza ngokukhawuleza kwi-15 micromolar, kodwa i-ATP yahlala isezantsi kwizixinaniso ezazikhuthaza ukusinda. Ulwakhiwo nokusinda zagcinwa ngaphandle kokubuyiselwa kwamandla, kunye nokuthotywa kwempendulo ye-mitochondria kwiiproteni ezingasongekanga nokususwa kwe-mitochondria nge-mitophagy. Eso siphumo sibeka idayi njengenciphisi yoxinzelelo lwe-reduction nolwe-oxidation kunokuba ibe ngumbuyiseli wamandla, njengoko kubhaliwe kwisifundo sokukhuselwa kweeseli ezamkela ukukhanya kwiretina.
Ithenda: uvavanyo apho imeko yemichiza yatshintsha kodwa izicubu azaphucuka
Umsebenzi wethenda ye-Achilles unezo ndlela zombini ngaphakathi kwephepha elinye yaye kufanelekile ukuwufunda ngononophelo. Ucazululo olupheleleyo lwesebe ngalinye lukwi-ngxelo yohlalutyo lwe-tendinopathy ye-Achilles ka-2026. Ithenda enesifo yabonisa ukuphela kwe-NAD+, umlinganiselo ophantsi we-NAD+ xa ithelekiswa ne-NADH, izalathisi ezibuthathaka zekhompleksi I, i-ATP ephantsi, ne-collagen engalungelelananga. I-methylene blue yabuyisela imeko yemichiza ye-NAD ne-ATP yaza yaphucula izalathisi ze-matrix kumalungiselelo eempuku, ezicubu zabantu ezikhutshiweyo, naweeseli.
Emva koko kwalandela ukuphazamiseka okubini okwenziwe ngabaphandi. Xa ikhompleksi I yayivaliwe nge-rotenone, idayi yayisakhusela imeko yemichiza ye-NAD+ nemilinganiselo enxulumene ne-ATP, kodwa ayizange inciphise umthwalo wee-oxidant, ibuyisele ulungelelwano lwe-collagen, okanye igcine amandla okuphila. Xa ukuveliswa kwe-AIF kwancitshiswayo, apho inkqubo yekhompleksi I yayingakhiwanga ngokupheleleyo kunokuba ivalwe ngamayeza, idayi yabuyisela izinto ezininzi: ulungelelwano lwe-NAD, uxinzelelo lwe-oxidation, umahluko wombane kwinwebu, nezalathisi ze-collagen. Isifundo esifunyanwayo sicacile. Inani elingcono le-NAD linokuxhaswa naxa ikhompleksi I ivaliwe, kodwa ukubuyiselwa kwezicubu kolu lungiselelo kwakuxhomekeke kwindlela yekhompleksi I enokusebenza. Utshintsho lomlinganiselo luyimfuneko kweli bali kodwa alwanelanga, ingongoma echazwe ngakumbi kwisifundo se-redox yethenda.
Indlela yokufunda ibango elilandelayo le-redox
Ukuhlola izinto ezintathu kusingatha uninzi lokutolika okungachananga. Okokuqala, buza ukuba umlinganiselo ngoweliphi icandelo nokuba uveliswe sesiphi isibini sezalathisi. Isiphumo se-lactate xa ithelekiswa ne-pyruvate kwi-cytosol asithethi nto ngokuthe ngqo nge-matrix ye-mitochondria. Okwesibini, buza ukuba iphepha linika ingxelo yotshintsho lomlinganiselo, uvimba opheleleyo omkhulu ngakumbi, okanye ukubuyiselwa kwe-ATP, uze uphathe nganye njengesiphumo esahlukileyo. Okwesithathu, buza ukuba yintoni eshiyeke yonakele: amafutha angalungiswanga, isiphene sekhompleksi I esingalungiswanga, okanye ukunqongophala kwe-ATP okungalungiswanga zonke ziyavela kula maphepha ecaleni kokuphucuka kwe-redox kokwenene.
Akukho nanye koku esisikhokelo seedosi. Zonke ezi zifundo zihlanu ngumsebenzi wezilwanyana, weeseli, okanye wezicubu ezilungiselelwe uvavanyo, ezinomonzakalo olawulwayo: ukutya okululwelo okune-ethanol, isifo seswekile esibangelwa yi-streptozotocin, iziphene zemfuza zekhompleksi I, i-rotenone, i-peroxide, ne-collagenase. Izixinaniso kwizitya zovavanyo azinakuguqulelwa kwiidosi zomlomo ngokuzijonga nje, yaye akukho mntu kula maphepha wathatha i-methylene blue ngenjongo yolungelelwano lwe-redox. Umongo odibanisa ifamakholoji ye-redox needosi unemida ecacileyo yaye uluncedo ngakumbi kunayo nayiphi na iprothokholi: i-methylene blue yenza i-oxidation ye-NADH ize itshintshe umlinganiselo olinganisiweyo, ii-sirtuin ziguqulela olo tshintsho ekususweni kwamaqela e-acetyl nasekucwangcisweni ngokutsha kwemetabolism kwezinye izicubu, yaye ukuba izicubu ziyaphucuka na kuxhomekeke kwinkqubo engenakuthathelwa indawo yidayi.