Ukuhlaziywa okujulile kwe-superoxide dismutase (SOD): "umqaphi we-antioxidant" womzimba 

Uma sikhuluma ngokuguga nempilo, sivame ukuzwa igama elithi "antioxidant." Kodwa bewazi yini ukuthi imizimba yethu inesimiso sokuzivikela esiyinkimbinkimbi se-antioxidant, futhi i-superoxide dismutase (SOD) iyilungu eliyinhloko lalesi simiso? Isebenza "njenge-free radical scavenger" ethembekile, ehlala ivikela amaseli ethu emonakalweni we-oxidative. Namuhla, ake sihlolisise lo “mqaphi omelene nokuguga.”

Ukuqonda Ama-Radical Amahhala: “Ababulali Abangabonakali” Bamaseli

Ngaphambi kokuqonda i-SOD, sidinga kuqala ukuqonda inhloso yayo eyinhloko - ama-radicals wamahhala.

Kalula nje, ama-radicals amahhala angama-molecule angazinzile akhiqizwa ngesikhathi sokushintshwa komzimba, futhi ama-superoxide anion radicals (O₂⁻) awuhlobo oluvame kakhulu futhi oluyingozi.

Ama-anion radicals e-Superoxide akhiqizwa ngezindlela eziningi: akhiqizwa ngokwemvelo ngesikhathi sokuphefumula kwe-mitochondrial, futhi amazinga awo anda kakhulu ngenxa yokungcoliswa kwemvelo, imisebe ye-ultraviolet, imisebe ye-electromagnetic (njengokusebenzisa isikhathi eside izinto zikagesi), ukuvivinya umzimba kanzima, ukucindezeleka kwengqondo, kanye nemikhuba yokuphila engenampilo njengokubhema nokuphuza utshwala.

Lawa ma-radicals mahhala anama-electron angabhanqiwe futhi asebenza kakhulu, asebenza “njengezigebengu” ezintshontsha ama-electron kumangqamuzana avamile, okuholela ekulimaleni kolwelwesi lwamangqamuzana, ukuguqulwa kwe-DNA, nokushintshashintsha kwamaprotheni.

Lokhu kulimala kwamangqamuzana okubangelwa ama-radicals mahhala kubizwa ngokuthi “i-oxidative stress,” futhi njengokugqwala kwensimbi, amangqamuzana ethu kancane kancane “aguga” kule nqubo.

Ucwaningo luye lwabonisa ukuthi ukucindezeleka okwenziwe nge-oxidative kuhlobene eduze nokuvela nokuthuthukiswa kwezifo eziningi, kuhlanganise nokuguga, isifo samathambo, izifo zenhliziyo, izifo ze-neurodeergenerative, ngisho nomdlavuza.

I-SOD: "Umugqa wokuqala wokuzivikela" wesistimu ye-antioxidant yomzimba.

I-Superoxide dismutase (SOD) iyi-antioxidant metalloenzyme etholakala kabanzi ezintweni eziphilayo futhi inomsebenzi obaluleke kakhulu wezinto eziphilayo.

Umsebenzi wayo oyinhloko uwukugqugquzela ukusabela kokungalingani kwe-superoxide anion radicals (.O2-), ukuwaguqulela ku-hydrogen peroxide (H2O2) kanye nomoya-mpilo (O2).  I-hydrogen peroxide ibuye ihlakazwe emanzini angenabungozi ngamanye ama-enzyme e-antioxidant (njenge-catalase ne-glutathione peroxidase), ngaleyo ndlela aqede ama-radicals mahhala futhi avikele amangqamuzana emonakalweni we-oxidative.

I-SOD idlala indima ebalulekile ekuvimbeleni izifo nasekuthuthukiseni amasosha omzimba womuntu, futhi idlala indima ebalulekile ezinqubweni zokulwa nokuguga, ukulwa ne-tumor, kanye ne-anti-inflammatory.

I-SOD: Into elwa nokuguga, ukutholwa okushintsha umhlaba.

I-SOD yaqala ukutholwa futhi yafundwa ososayensi ngawo-1930. Ngo-1938, uchwepheshe we-biomolecular waseMelika uMichael McCord, ngaphansi kokuqondisa kukaFredrick Fridovich, wakhipha ngempumelelo i-superoxide dismutase (SOD) kumangqamuzana egazi abomvu ezinkomo okokuqala ngqa. Ngo-1988, ososayensi abathathu abadumile-uFerid Murad, uRobert Furchgott, noLouis Ignarro, kamuva owawina uMklomelo KaNobel Kwezokwelapha-owamenyezelwa emhlabeni:

“Ukuntuleka nokusebenza okuncishisiwe kwe-SOD kuyizimbangela eziyinhloko zokuguga, ukugula nokufa kwabantu.

Ngokusekelwe ku-ion yensimbi eboshelwe endaweni yawo esebenzayo, ama-SOD ahlukaniswe ikakhulukazi izigaba ezine:

Ukuhlukaniswa nokusabalalisa kwe-SOD

I-Cu/Zn-SOD: I-Blue-green ngombala, ikakhulukazi etholakala ku-cytoplasm yamaseli e-eukaryotic, futhi iwuhlobo olusatshalaliswa kakhulu lwe-SOD. I-SOD emangqamuzaneni egazi abomvu nasemangqamuzaneni esibindi ikakhulukazi alolu hlobo.

I-Mn-SOD: Umbala opinki, otholakala ikakhulukazi ku-mitochondria yama-prokaryotes nama-eukaryotes, futhi ubalulekile ekugcineni ukusebenza kwe-mitochondrial.

I-Fe-SOD: Umbala onsundu ngokuphuzi, yaqale yatholwa ku-*Escherichia coli*, futhi itholakala kakhulu kumaseli e-prokaryotic kanye nama-chloroplast amaseli ambalwa ezitshalo.

I-Ni-SOD: I-Emerald eluhlaza ngombala, ikakhulukazi etholakala ezintweni eziphilayo eziphansi njenge-cyanobacteria, i-green algae, kanye ne-*Streptomyces*.

Imithombo namafomu omkhiqizo we-SOD

I-SOD yemvelo ikhona kabanzi ezilwaneni, ezitshalweni, nasezilwanyaneni ezincane, kodwa isizinda esiqondile sibhekana nezinkinga ezifana nokusebenza kahle okuphansi nokuzinza okubi. Njengamanje, imikhiqizo ye-SOD etholakalayo ethengiswayo ikakhulukazi ivela emithonjeni elandelayo:

Imithombo yezilwane: Imikhiqizo yokuqala yayikhishwa kakhulu egazini lezilwane ezinjengezinkomo nezimvu (Cu/Zn-SOD). Kodwa-ke, le mikhiqizo inesisindo esikhulu samangqamuzana futhi iphulwa kalula yi-asidi yesisu lapho ithathwa ngomlomo.  Ngaphezu kwalokho, izingxenye ezithathwe ezilwaneni zingase zibangele ukungezwani komzimba noma zithwale amagciwane.

Imithombo yezitshalo: Ikhishwe ezitshalweni ezithile (ezifana ne-sea buckthorn ne-spirulina), kodwa umsebenzi wazo uthintwa kalula yizimo zokukhishwa nokugcinwa kwazo, futhi ziphulwa kalula ngama-enzyme okugaya lapho zithathwa ngomlomo, okuholela ekunciphiseni kwe-bioavailability.  Eminye imithombo futhi inezindleko eziphezulu zokukhipha noma ingase iqukathe amanani omkhondo wokungcola okutholakala ezitshalweni.

Ukuvutshelwa kwe-Microbial (ikakhulukazi kusetshenziswa amagciwane akhiwe kabusha ngofuzo) sekuyindlela ephelele yokukhiqiza ye-SOD yokuhweba, enezinzuzo ezibalulekile:

Iphephile futhi ayinabungozi: Igwema ngokuphelele ukungcoliswa kwe-pathogen (njenge-mad cow disease) kanye nobungozi be-immunogenic bemithombo yezilwane (njengegazi lezinkomo), ukuqinisekisa ukuphepha okuphezulu kakhulu.

Isivuno esiphezulu nezindleko eziphansi: Ngobuchwepheshe bonjiniyela bezakhi zofuzo, amagciwane anjiniyela afana ne-E. coli ne-yeast angashintshwa ukuze aveze ngempumelelo izinhlobo ezithathwe umuntu noma ezithile ze-SOD. Isivuno siphezulu kakhulu kunesokukhishwa kwezilwane nezitshalo, kunciphisa kakhulu izindleko zokukhiqiza.

Ukuhlanzeka okuphezulu nekhwalithi ezinzile: Ikhiqizwe emathangeni okuvutshelwa avaliwe, angenalutho, inqubo iyalawuleka kakhulu futhi kulula ukuyihlanza phansi komfula. Umkhiqizo wokugcina unokuhlanzeka okuphezulu kanye nekhwalithi engaguquki phakathi kwamaqoqo.

Akukho ukungqubuzana kwezimiso zokuziphatha: Yonke inqubo yokukhiqiza ayibandakanyi ukuhlatshwa kwezilwane noma ukucekelwa phansi kwezitshalo ngezinga elikhulu, ukuthobelana nokuvikelwa kwemvelo okuluhlaza kanye nezidingo zokuziphatha zenhlalakahle yezilwane.

Amafomu omkhiqizo we-SOD

Amalungiselelo omjovo: Asetshenziswa njengemithi kadokotela yokwelapha i-adjuvant ye-osteoarthritis, ukugula ngemisebe, njll.  I-Recombinant human SOD inketho ekhethwayo yezicelo zomtholampilo ngenxa yephrofayili yayo yokuphepha ephezulu.

Amalungiselelo omlomo: Kuhlanganisa amaphilisi, amalozenji, njll., eminye imikhiqizo isebenzisa i-nanotechnology noma ukuguqulwa kwe-glycosylation ukuze kuthuthukiswe ukutholakala kwe-bioavailability.

Izithasiselo zezimonyo: Zisetshenziselwa izakhiwo zazo ze-antioxidant ukubambezela ukuguga kwesikhumba. I-Recombinant SOD ingaba "miniaturized" ngokusebenzisa ubunjiniyela bezakhi zofuzo, okwenza kube lula ukungena ku-stratum corneum yesikhumba futhi ibe nemiphumela ejulile ye-antioxidant.

Ukudla kwezempilo: Kwengezwe njengesithako esilwa ne-antioxidant ekudleni okuhlukahlukene kwezempilo. I-SOD etholakala kwi-Microbial fermentation ivame ukusetshenziswa ekwakhiweni kwama-protein powders, ama-probiotics, nokunye ukudla ngenxa yezindleko zayo eziphansi nokuphepha okuphezulu.