I-Mitochondria yinto enqwenelekayo ye-organelles ehlala phantse yonke iseli emzimbeni wethu. Ngokungafani nezinye iinxalenye zeseli, i-mitochondria iyicandelo elithile. Enyanisweni, ziphantse zizinto ezihlukeneyo, eziphathekayo zemizimba ezihluke ngokupheleleyo kulo lonke umzimba. Ngokomzekelo, ngokuqhelekileyo siyamkela ukuba sizuza ilifa lezinto zethu zofuzo ezivela kumama wethu nesiqingatha esivela kubabawo.
Oku akunjalo. I-DNA yeMitochondrial ihlula ngendlela eyahlukileyo kwaye izuze ifa elikuphela ngokupheleleyo kumama.
Inzululwazi ezininzi zikholelwa ukuba i-mitochondria ngumzekelo wobudlelwane obude be-symbiotic, apho iibhakteria zadlulileyo zidibene kunye neeseli zethu ukuze iiseli zethu kunye neebhaktheriya zithembeke. Sidinga i-mitochondria ukwenzela ukuba sisebenze ininzi yamandla ethu amaseli kufuneka aphile. I-oksijeni esiphefumulayo igalela inkqubo engenakwenzeka ngaphandle kwale nxalenye encinane.
Njengoko kukhangeleka njengemithichondria, banokungonakalisa njengokuba nayiphi na inxalenye yomzimba wethu. Ukuguqulwa kwefa kwi-DNA ye-mitochondrial kunokukhokelela kwimimandla eyahlukeneyo yempawu ezahlukileyo. Oku kunokukhokelela kwi-syndromes ecinga ukuba yinto engaqhelekanga kwaye ayinqabile kakhulu, kodwa ngoku ibonakala iyinto eqhelekileyo kunokuba icinga ngaphambili. Iqela laseNyakatho yeNgilani lafumana ukuxhaphaka kwaba malunga nabantu abayi-15,200.
Inani elikhulu, malunga ne-1 ngo-200, latshintshile, kodwa ukuguqulwa komzimba kwakungekho uphawu.
Inkqubo yeentlanzi ixhomekeke kakhulu kwi-oksijini ukwenzela ukuba yenze umsebenzi wayo, kwaye oko kuthetha ukuba izithambo zethu zifuna imitochondria ukuba isebenze kakuhle. Xa i-mitochondria ingaphumeleli, inkqubo ye-nervous is often the first to suffer.
Iimpawu zeMitochondrial Disease
Uphawu oluqhelekileyo olubangelwa sisifo se-mitochondrial sisifo se-myopathy, esithetha isifo se-muscle.
Ezinye iimpawu ezingabonakali zibandakanya iingxaki zombono, iingxaki zokucinga, okanye ukuhlanganiswa kweempawu. Iimpawu zihlala ziqoqa ndawonye ukuze zenze enye ye-syndromes eyahlukeneyo.
I-Ophthalmoplegia yangaphandle engapheliyo ye-Ophthalmoplegia (i-CPEO) - kwi-CPEO, imisipha yamehlo ikhubazekile. Oku kudla ngokubakho xa abantu beemithathu zabo, kodwa bangenzeka nanini na. Umbono ombini awunqabile, kodwa ezinye iingxaki ezibonakalayo zifunyanwa ngophando logqirha. Ezinye iifom, ngakumbi xa zifunyanwa kwiintsapho, zihamba neengxaki zengxoxo, ukuthetha okanye ukugwinya iingxaki, i- neuropathies , okanye ukudandatheka.
I-Kearns-Sayre syndrome - i-Kearns-Sayre syndrome iphantse ifana neCPEO, kodwa ngezinye iingxaki ezingaphezulu kunye nobudala bokuqala. Iingxaki ziqala xa abantu bephantsi kweminyaka engama-20. Ezinye iingxaki zibandakanya i-retinopathy ye-pigmentary, i- cerebellar ataxia , iingxaki zentliziyo kunye neentsilelo zeengqondo. I-Kearns-Sayre syndrome inamandla ngaphezu kweCPEO, kwaye ingakhokelela ekufeni ngeshumi leminyaka yobomi.
I-Leber Hereditary Optic Neuropathy (LHON) - I-LON ihlobo lokulahlekelwa kombono olubangelwa ukuphunga kumadoda amancinci.
I-Leigh Syndrome - Eyaziwa ngokuba yi-necrotizing encephalomyelopathy, i-Leigh syndrome ngokuqhelekileyo ivela kubantwana abancinci kakhulu. i-disorder yenza ukuba i-ataxia, ukuthinteka , ubuthathaka, ukulibaziseka kokuphuhliswa, i- dystonia , kunye nokunye. I-imagery resonance imaging (MRI) yengqondo ibonisa uphawu olungavumelekanga kwi-basal ganglia. Esi sifo sivame ukubulawa phakathi kweenyanga.
I-encephalopathy ye-mitochondrial ne-lactic acidosis kunye ne-stroke-like episodes (i-MELAS) - I- MELAS yenye yezona zixhaphaka kakhulu zezifo ze-mitochondrial. Ilifa elivela kumama. Esi sifo kubangela iziqhelo ezifana nezibetho, ezingabangela ubuthathaka okanye ukulahleka kombono. Ezinye iimpawu ziquka ukutshatyalaliswa, ukuthatha imfucuza, ukuhlanza, ukulahlekelwa kwindlebe, ubuthathaka bomzimba kunye nesigxina esifutshane. Isifo esivame ukuqala ebuntwaneni kwaye siphumelele ekudemeni kwengqondo. Inokuthi ifunyaniswe ngamanqanaba aphakamileyo e-lactic acid egazini kunye nokubonakala "kwefayili ebomvu ebomvu" ngokubonakala kwe-muscle phantsi kwe-microscope.
Ukuqukulwa kwe-Myoclonic ngeemfubomfubomfubomvu ezimnyama (MERRF) - I-Myoclonus yintsimbi ekhawuleza kakhulu, efana neyonto eninzi ngaphambi kokuba silele. I-myoclonus e-MERRF iqhubeka rhoqo kwaye ilandelwa yintlupheko, i-ataxia, kunye nobuthakathaka bemisipha. Iintlupheko, iingxaki zombono, i-peripheral neuropathy, kunye ne-dementia.
Isisithulu esingumama nesifo sikashukela (MIDD) - Le ngxaki ye-mitochondrial ihlala ichaphazela abantu abaneminyaka engama-30 ukuya kwe-40 ubudala. Ukongeza kokulahlekelwa kwindlebe kunye nesifo sikashukela, abantu abane-MIDD banokulahleka kombono, ubuthakathaka besifo, iingxaki zentliziyo, isifo sesifo, isifo sesisu, kunye nesigxina esifutshane.
I-encephalopathy ye-Mitochondrial neurogastrointestinal encephalopathy (i-MNGIE) - Oku kubangela ukungahambi kakuhle kwamathumbu, oku kunokukhokelela ekubandezelekeni kwesisu nangomzimba. Iingxaki kunye nokunyakaza kwamehlo nazo ziqhelekile, njengokuba i-neuropathies kunye nomxholo omhlophe utshintsha kwintsingiselo. Ingxaki ifika kuyo nayiphi na indawo ukusuka ebuntwaneni ukuya kumahlanu kodwa ixhaphake kubantwana.
I-neuropathy, i-ataxia kunye ne-retinitis pigmentosa (i-NARP) - Ukongezelela kwiingxaki zeengxaki zengxube kunye ne-clumsiness, i-NARP inokubangela ukulibaziseka kokuphuhliswa, ukuxhamla, ubuthathaka, kunye nengqondo.
Ezinye izifo ze-mitochondrial ziquka i-Pearson syndrome (isifo se-anemia ne-pancreatic dysfunction), i-Barth syndrome (i-X-linked cardiomyopathy, i-mitochondrial myopathy, kunye ne-cyclic neutropenia), ukukhawuleza kokukhula, i-amino aciduria, i-cholestasis, i-amino aciduria, i-cholestasis, ukugqithisa isinyithi, i-lactic acidosis kunye nokufa kwangaphambili (I-GRACILE ).
Ukuchonga izifo zeMitochondrial Diseases
Ngenxa yokuba isifo se-mitochondrial singabangela uluhlu lweempawu eziphazamisayo, ezi ngxaki ziba nzima nakumaziko aqeqeshiwe ukuba aqonde. Kwiimeko ezingavamile apho zonke iimpawu zibonakala zibalaseleyo ngenxa yesifo esithile, ukuhlolwa kofuzo kungenziwa ukuqinisekisa ukuxilongwa. Ngaphandle koko, ezinye iimvavanyo zingafuneka.
I-Mitochondria ibangela uxanduva lwe-aerobic metabolism, eninzi lwethu lisisebenzisa imihla ngemihla ukuze sihambe. Xa i-aerobic metabolism iphelile, njengokuba usebenze ngamandla, umzimba unesistim yokugcina isiphumo sokubangela i-lactic acid. Le yinto eyenza izihlunu zethu zitshise kwaye zitshise xa sizinzima ixesha elide. Ngenxa yokuba abantu abanesifo se-mitochondrial banakho ukukwazi ukusebenzisa i-aerobic metabolism yabo, i-lactic acid iyakha, kwaye le nto ingalinganiswa kwaye isetyenziswe njengophawu lokuba into ephosakeleyo nge-mitochondria. Ezinye izinto zinokunyusa i-lactate, nangona kunjalo. Ngokomzekelo, i-lactic acid kwi- cerebrospinal fluid inokuphakanyiswa emva kokufumana ukuxhwala okanye ukushaya. Ngaphezu koko, ezinye iintlobo zesifo se-mitochondrial, njenge-Leigh syndrome, zihlala ziphantsi kwamanqanaba athile.
Uvavanyo olusisiseko luquka amanqanaba e-lactate kwiplasma kunye ne-cerebrospinal fluid. I-Electrocardiograms ingakwazi ukuvavanya i-arrhythmias, enokuthi ibulale. Umfanekiso we-resonance (magnetic resonance image) (MRI) unokukhangela utshintsho lomcimbi omhlophe . I-Electromyography ingasetyenziselwa ukuphanda ngezifo zesifo. Ukuba kukho inkxalabo yokubamba, i-electroencephalography inokuyalelwa. Ukuxhomekeka kwiimpawu, ukuhlolwa kwee-audiology okanye i-ophthalmology kungaphakanyiswa.
I-biopsy ye-muscle yenye yezona ndlela zithembekileyo zokufumana iingxaki zemitochondrial. Uninzi lwezifo ze-mitochondrial ziza ne-myopathy, ngamanye amaxesha nangona kungekho zibonakaliso ezibonakalayo ezifana nobuhlungu besisu okanye ubuthathaka.
Unyango kwiiMitochondrial Diseases
Ngeli xesha, akukho nonyango oluqinisekisiweyo lweengxaki zemitochondrial. Ugxininiso ekulawuleni iimpawu njengoko zivela. Nangona kunjalo, ukuxilongwa kakuhle kukunceda ukulungiselela ukuphuhliswa kwexesha elizayo, kwaye kwimeko yesifo esizuze ilifa, kunokuchaphazela ukucwangcisa intsapho.
Isishwankathelo
Ngamafutshane, isifo se-mitochondrial kufuneka sikhankanywe xa kukho ukudibanisa iimpawu ezibandakanya intliziyo yesisu, ingqondo okanye amehlo. Ngelixa ilifa lomama linokuthi licebise, kunokwenzeka kwaye kwinto eqhelekileyo ukuba isifo se-mitochondrial siphumelele ekutshintsheni kwi-DNA yenyukliya, ngenxa yokusebenzisana phakathi kwezinto eziphathekayo ze-gene and the mitochondria. Ukongezelela, ezinye izifo zihamba ngokukhawuleza, zithetha ukuba zenzeka okokuqala ngaphandle kokuba zizuze ifa. Izifo zeMitochondrial zisabonakali kwaye zilawulwa kakuhle ngutitshala onokuqonda ngokucacileyo kweli nqanaba leesifo segazi.
Imithombo
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