I-Glucuronidation iyinqubo yebhayoloji lapho i-glucuronic acid, i-asidi engokwemvelo eyenzeka ngokwemvelo, ibophezela ezintweni zangaphandle ukuze kube lula ukuqedwa kwazo. Le nqubo yenzeka ngokuyinhloko esibindini futhi iyindlela ebalulekile yokukhishwa kwe-detoxification, njengoba iguqula izinto ezincibilikayo zamafutha zibe izinhlanganisela ezincibilikayo emanzini, okwenza kube lula ukuphuma kwazo ngezinso. I-Glucuronic acid ikhiqizwa ku-glucose futhi idlala indima ebalulekile ekuqedeni ubuthi nezinto ezingafuneki emzimbeni.
Qonda inqubo yeGlucuronidation nokubaluleka kwayo emzimbeni womuntu.
I-Glucuronidation iyinqubo yokuhlanganisa lapho i-molecule ye-glucuronic acid ibopha entweni yangaphandle, iyenze incibilike kakhulu emanzini futhi yenze kube lula ukuphuma kwayo emzimbeni. Le nqubo ingenye yezindlela eziyinhloko ze-biotransformation yezinto ezinobuthi nezidakamizwa emzimbeni womuntu.
I-Glucuronic acid iyi-carboxylic acid ekhona emzimbeni eyakhiwe kusuka ku-glucose. Ibalulekile ku-glucuronidation, eyenzeka ngokuyinhloko esibindini, lapho ama-enzyme anesibopho sokuhlanganisa i-glucuronic acid nezinto zangaphandle ekhona ngobuningi.
Lapho into igaywa esibindini, ingena kunqubo ye-glucuronidation, lapho i-molecule ye-glucuronic acid ibopha kuyo, yakhe i-conjugate ekhishwa kalula emchamweni noma e-bile. Le nqubo ibalulekile ekuqedeni izinto ezingaba ubuthi emzimbeni, njengemithi, amahomoni, ubuthi bemvelo, kanye nemikhiqizo ye-metabolic.
I-Glucuronidation ibalulekile ekugcineni i-homeostasis yomzimba, ukuqinisekisa ukuthi izinto zangaphandle ziqedwa ngokuphumelelayo. Ngaphezu kwalokho, kubalulekile ekulawuleni amazinga e-hormone kanye ne-metabolite emzimbeni, okufaka isandla ebhalansi yamakhemikhali edingekayo ekusebenzeni kahle kwesitho.
Kuyinqubo ebalulekile yokuqeda izinto eziyingozi nokugcina ibhalansi yamakhemikhali omzimba, iqinisekisa ukusebenza kahle kwezinhlelo ze-metabolic kanye nokuvikelwa emonakalweni obangelwa izinto ezinobuthi.
Izigaba ezi-3 zesenzo somuthi: thola ukuthi lezi zigaba zisebenza kanjani.
I-Glucuronidation iyinqubo ebalulekile ekusetshenzisweni kwezidakamizwa emzimbeni womuntu. Lesi sinyathelo sibandakanya ukuboshwa kwe-glucuronic acid enhlanganisela yangaphandle, ukwakha i-conjugate ekhishwa kalula ngumzimba. Ake sihlole izigaba ezintathu zesenzo somuthi nokuthi i-glucuronidation idlala indima ebalulekile kanjani kule nqubo.
1. Ukumuncwa: Isigaba sokuqala sesenzo somuthi ukumuncwa kwawo ngumzimba. Ngemuva kokuphathwa, umuthi uthathwa yi-gastrointestinal tract bese ungena egazini. Uma usungene egazini, umuthi ungasatshalaliswa ezicutshini ezihlosiwe lapho uzokwenza khona umphumela wawo wokwelapha.
2. I-Metabolism: Isigaba sesibili sesenzo somuthi i-metabolism yawo emzimbeni. Ngesikhathi se-metabolism, umuthi uguqulwa ngama-enzyme esibindi abe yizinhlanganisela ezahlukahlukene, kufaka phakathi i-glucuronic acid. Le asidi ihlanganiswa nomuthi ukuze ikwazi ukuncibilika emanzini futhi yenze kube lula ukuphuma kwayo ngezinso.
3. Ukukhishwa: Isigaba sesithathu nesokugcina sesenzo somuthi ukuphuma kwawo emzimbeni. Ngemuva kokuhlanganiswa ne-glucuronic acid, umuthi ukhishwa emzimbeni ngokuyinhloko ngomchamo. Le nqubo yokukhipha ibalulekile ukuvimbela ukunqwabelana kwezinto ezinobuthi emzimbeni nokugcina ibhalansi ye-homeostatic.
Ukuqonda izigaba ezi-3 zesenzo somuthi nokuthi i-glucuronidation ibandakanyeka kanjani kule nqubo kubalulekile ukuze kuqinisekiswe ukusebenza kahle nokuphepha kokwelashwa kwezidakamizwa.
Izindlela eziyinhloko zokususa imfucuza emzimbeni womuntu: thola ezintathu eziyinhloko.
Uma sikhuluma ngokususwa kwemfucuza emzimbeni womuntu, kubalulekile ukuqonda izindlela eziyinhloko umzimba ozisebenzisayo ukukhipha izinto ezingafuneki. Kunezindlela ezintathu eziyinhloko zokuqeda imfucuza: izinso, isibindi, kanye nomgudu wamathumbu.
Izinso zidlala indima ebalulekile ekukhipheni ukungcola emzimbeni, zihlunge igazi futhi zikhiqize umchamo, oqukethe izinto ezingafuneki ezikhishwa emzimbeni. Isibindi siphinde sibe isitho esibalulekile ekuqedeni udoti, njengoba sinesibopho sokugawula kanye nokukhipha izinto ezinobuthi, njengemithi kanye nobuthi bemvelo.
Ipheshana lamathumbu nalo liyindlela ebalulekile yokuqeda imfucuza, njengoba kuphuma ngalo indle emzimbeni. Le nqubo isiza ukugcina ibhalansi yomzimba futhi ivimbele ukuqoqwa kwezinto eziyingozi.
Iyini i-glucuronidation ne-glucuronic acid?
I-Glucuronidation iyinqubo ebalulekile esibindini lapho i-glucuronic acid ihlanganiswa nezinto ezinobuthi noma ezingafuneki, izenze zincibilike emanzini futhi zenze kube lula ukuqedwa kwazo emzimbeni. Le nqubo ibalulekile ukuze kukhishwe ubuthi emzimbeni nokuqinisekisa ukuthi izinto eziyingozi ziqedwa ngokuphumelelayo.
I-Glucuronic acid iyi-asidi ephilayo edlala indima ebalulekile ku-glucuronidation, njengoba ibophezela ezintweni ezinobuthi, yakha ama-conjugates akhishwa ku-bile noma umchamo. Ngaphandle kwe-glucuronic acid, inqubo yokuqeda imfucuza ingaba sengozini, futhi izinto eziyingozi zinganqwabelana emzimbeni.
Qonda umphumela wesiqephu sokuqala somuthi emzimbeni womuntu.
Lapho umuthi udliswa, uthola inqubo ye-metabolism emzimbeni womuntu. Enye yezindlela eziyinhloko ezihilelekile kule nqubo i-glucuronidation, ehlanganisa ukuhlanganiswa komuthi ne-glucuronic acid ukuze kube lula ukuphuma kwawo.
Lapho ingena esibindini, umuthi ugaywa ube yizinhlanganisela ezihlukahlukene, kuhlanganise ne-glucuronic acid conjugates. Lawa ma-conjugate ancibilika kakhulu emanzini kunomuthi wokuqala, okwenza kube lula ukuqedwa kwawo yizinso.
Kubalulekile ukuqaphela ukuthi ukudlula kokuqala komuthi esibindini kungaba nomthelela omkhulu ekutholakaleni kwawo kwe-bioavailability. Phakathi nale nqubo, ezinye izidakamizwa zingase zenziwe nge-metabolized ngaphambi kokufinyelela ukujikeleza kwesistimu, ukunciphisa inani elitholakalayo ukukhiqiza umphumela oyifunayo.
Ngakho-ke, i-glucuronidation kanye nokuhlangana ne-glucuronic acid kudlala indima ebalulekile ekusetshenzisweni kwezidakamizwa emzimbeni womuntu, kube nomthelela ekusebenzeni nasekuphepheni kwazo. Ukuqonda lezi zinqubo kubalulekile ekuqinisekiseni ukusetshenziswa okufanele nangempumelelo kwemithi.
Iyini i-glucuronidation ne-glucuronic acid?
A i-glucuronidation iyindlela ebalulekile yokukhipha ubuthi emzimbeni weselula. Iqukethe ukudlulisa i-molecule ye-glucuronic acid ezinhlobonhlobo zezinhlanganisela ezinobuthi engqamuzaneni, okwenza kube lula ukuqedwa kwazo ngokushesha.
Ibhekwa njengendlela ye-metabolic ye-biotransformation, njengoba ihilela ukuguqulwa kwe-substrate ibe umkhiqizo wamakhemikhali oshintshwe isakhiwo onezici ezihlukahlukene ze-biochemical. Lolu shintsho lwenzeka ngokusabela kwamakhemikhali okukodwa noma ngaphezulu okubangelwa ama-enzyme abizwa ngokuthi ama-transferases.
Le ndlela yokukhipha ubuthi emzimbeni yenziwa izinhlobonhlobo zezinto eziphilayo, okuhlanganisa izilwane, izitshalo, namagciwane. Kuyo ngayinye yazo, ukuqedwa kokugcina kwezinhlanganisela ze-glucunorate kwenzeka ngezinqubo ezihlukene zokuphuma kokugcina.
Njengoba i-glucuronidation inyusa ukunyibilika okune-aqueous kwezinhlanganisela, iphinde yakha indlela yokuqalisa nethuthukisayo yokusatshalaliswa okusheshayo kwama-metabolites okubonisa njengamahomoni.
Ukusabela kwe-cell detoxification
Wonke amaseli asungule izindlela eziningi zokuqeda ubuthi. Lezi zakha izindlela ze-metabolic ezibalulekile njengalezo lapho zithola khona amandla adingekayo ukuze zifeze zonke izinqubo zazo ezibalulekile.
Lezi zindlela ngokuvamile zihluke kakhulu ngokwesimo sokusabela kwe-enzymatic okukuzo. Kodwa-ke, zonke ziyahlangana ekuguquleni noma ekuguquleni amakhemikhali e-metabolite engapheli (ekhiqizwe ngaphakathi kweseli) kanye ne-xenobiotics (inhlanganisela etholwe kuseli ngaphandle) zibe izinhlanganisela ezingakhishwa kalula.
Lezi zinguquko zibandakanya ukufakwa kwamaqembu amakhemikhali asebenzayo akhulisa ukuncibilika kwenhlanganisela okufanele ikhishwe. Ukusabela okunesibopho sale nqubo ngokwesiko kuhlukaniswa njengokusabela kwesigaba I kanye nesigaba II.
Ukusabela kwesigaba I kuhilela ukudluliswa kwamaqembu e-polar, njengamaqembu e-hydroxyl noma e-carboxyl, ngokusabela kwe-hydrolytic noma kwe-oxide-reduction. Lawa maqembu angakwazi ukukhiqiza amasayithi abophezelayo kwezinye izinhlanganisela ezifakwe ngesikhathi sokuhlangana noma ukusabela kwesigaba II.
Phakathi kwezinhlanganisela eziningi ezingahlanganiswa yilolu hlobo lokusabela, i-glucuronic acid ingenye yezinto ezivame ukusetshenziswa, ngokuqondile ngoba inyibilika kakhulu emanzini. Lokhu kusabela okuqondile kubizwa ngokuthi i-glucuronidation.
I-Glucuronic acid
I-Glucuronic acid iyi-carbohydrate ekhiqizwa kumaseli nge-oxidation ye-sugar nucleotide uridine diphosphate glucose (UDP-Glucose), ukusabela okubangelwa i-enzyme UDP-Glucose dehydrogenase.
Ukwakheka kwayo kwamakhemikhali kufana neglucose, ngomehluko oyingqayizivele wokuthi iqembu le-carboxyl lengezwe ku-carbon six. Njengoshukela, iyinhlanganisela encibilika kakhulu emanzini, uma kubhekwa ukuba khona kwamaqembu amaningi asebenzayo e-polar hydroxyl kanye ne-carboxyl esakhiweni sayo.
Le mvelo ephezulu encibilikayo emanzini iyenza ibe i-substrate ekahle yokusabela okuningi kwe-metabolic okudinga usizo lwezinhlanganisela nalesi sici ukuze kwandiswe ukunyibilika kwezinye izinhlanganisela. Izibonelo zalokhu kusabela yilezo ezihilelekile ekusabalaliseni nasekukhipheni izindlela zezingxube.
Eqinisweni, phakathi kwemisebenzi eyinhloko yezinto eziphilayo okuthiwa le acid carboxylic, ngaphezu kokubamba iqhaza kwayo ekuhlanganiseni uvithamini C, okulandelayo kuyagqama: ukubambisana kwayo ekwandiseni biodistribution hormone kuwo wonke umzimba kanye nezinqubo zokuqeda ubuthi endogenous kanye exogenous emchameni.
Inqubo yeGlucuronidation
I-Glucuronidation ingenye yezindlela ezibaluleke kakhulu zokusabela esigabeni II. Ibamba iqhaza ekuqedeni inani elikhulu lama-metabolites angapheli, njenge-bilirubin kanye nezinhlobonhlobo eziningi ze-xenobiotics, ngokuguqula lokhu okulandelayo kube izinhlanganisela ezincibilikayo emanzini.
Ukusabela kwamakhemikhali kwe-glucuronidation kuhlanganisa ukudluliswa noma ukunamathiselwa kwe-molecule ye-glucuronic acid ukuze ihlanganiswe nokuncibilika okuphansi kwamanzi okunamaphoyinti okunamathiselwe amakhemikhali esakhiweni sayo. Umphumela walokhu kusabela ubizwa ngokuthi i-glucuronide conjugate.
Kunezinhlobonhlobo eziningi zamaqembu amakhemikhali asebenzayo angahlanganiswa ne-glucuronic acid ukuze akhe ama-glucuronides. Ezinye zazo zigcwele umoya-mpilo, isibabule, ama-athomu e-carbon, ne-nitrogen.
Ama-Glucuronides akhiqizwa ezilwaneni ezincelisayo akhishwa ngomchamo noma nge-bile, kanti ezintweni ezinengqamuzana elilodwa, njengamagciwane, lokhu kususwa kwenzeka ngokusabalaliswa kalula kulo lonke ulwelwesi. Ngenxa yalesi sizathu, le nqubo ibhekwa njengenqubo yokuqeda ubuthi.
Njengoba le nqubo ibalulekile ekugcineni i-homeostasis yamangqamuzana, ngaphezu kokuqinisekisa ukusatshalaliswa okusheshayo kwezinhlanganisela kuwo wonke umzimba (okwandisa ukutholakala kwazo), sekugxilwe ekuphenyweni okuningi kwemithi.
Ama-Transferase
Wonke ama-enzyme enza ukusabela okubandakanya ukudluliselwa kweqembu elisebenzayo aziwa ngokuthi ama-transferases. Ukusabela kwe-enzymatic kwe-glucuronidation kwenziwa umndeni othile wokudluliswa okuye kwabizwa ngokuthi i-UDP-glucuronosyltransferases (UGT).
Izakhi zofuzo ezifaka ikhodi ye-UGT zitholwe ezintweni eziyinkimbinkimbi njengezilwane nezitshalo, kanye nakumabhaktheriya. Ngakho-ke, le nqubo ye-metabolic esabalele kungenzeka ukuthi yavela kubhaktheriya njengendlela yokuqala yokuqedwa kwamangqamuzana nokukhipha.
Ucwaningo lwezofuzo lubonise ukuthi ezintweni eziningi eziphilayo, ibhange lama-isoforms e-UGT ahlukene lifakwe ikhodi ngezakhi zofuzo okulandelana kwazo kugcinwe kakhulu kumagciwane, izitshalo nezilwane.
Eqinisweni, wonke umndeni wama-UGT ahlukene ungatholwa ubhalwe ngekhodi isakhi sofuzo esisodwa esifundwa ngezinhlanganisela ezihlukahlukene ukuze kukhiqizwe imikhiqizo ehlukene yamaprotheni.
Izindlela zokuqeda ama-glucuronylated compounds
Uma kubhekwa uhlobo lwe-hydrophilic lwemikhiqizo ye-glucuronidation, ukuqedwa kwayo ngokusakazwa mahhala kulwelwesi lonke akunakwenzeka. Ngakho-ke, ukuphuma kwabo engqamuzaneni kulawulwa izindlela ezilula zokusabalalisa, ezidinga usizo lwabathuthi abathile be-efflux.
Izinga lapho lezi zinhlanganisela zihanjiswa ziphuma engqamuzaneni linquma ukuthi inqubo ye-glucuronidation yenzeka ngokushesha kangakanani. Amazinga aphezulu okuphuma ahlotshaniswa kahle nokukhuphuka kwe-glucuronidation.
Izinkomba
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