I-mitochondria iyinhlangano ephilayo ekhangayo ehlala cishe cishe wonke amangqamuzana emzimbeni wethu. Ngokungafani nezinye izingxenye zeseli, i-mitochondria cishe iseliyodwa. Eqinisweni, ziyizinto eziphilayo ezihlukene, ezinezinto eziphilayo ezihluke ngokuphelele kulo lonke umzimba. Isibonelo, ngokuvamile siyakwamukela ukuthi sizuze ingxenye yezinto zethu zofuzo ezivela kumama wethu nengxenye kubaba wethu.
Lokhu akulona iqiniso ngempela. I-DNA ye-mitochondrial ihlukana ngendlela ehlukile futhi izuze ifa elingunaphakade kumama.
Ososayensi abaningi bakholelwa ukuthi i-mitochondria iyisibonelo sobuhlobo obudala be-symbiotic, lapho amabhaktheriya adlulele khona isikhathi eside ngamaseli ethu ukuze amangqamuzana ethu namabhaktheriya abe ngaphansi komunye nomunye. Sidinga i-mitochondria ukuze sisebenze iningi lamandla amaseli ethu adinga ukusinda. I-oksijeni esiphefumula ifaka inqubo engenakwenzeka ngaphandle kwalesi sitho esincane.
Ngokuthakazelisayo njenge-mitochondria, ziyakwazi ukulimala njenganoma iyiphi enye ingxenye yomzimba wethu. Izinguquko ezithandwayo ku-DNA ye-mitochondrial zingaholela ezinhlobonhlobo eziningi ezihlukahlukene. Lokhu kungaholela kuma-syndromes okucatshangwa ukuthi akuvamile futhi angavamile kakhulu, kodwa manje kubonakala sengathi evamile kunalokho okucatshangwa ngaphambilini. Iqembu eliseNyakatho Melika eNgilandi lithole ukusabalala okungaba ngu-1 kwabangu-15 200 abantu.
Inombolo enkulu, engaba ngu-1 ku-200, ibe nokuguquguquka, kodwa ukuguqulwa komzimba kwakungabonakali.
Uhlelo lwezinzwa luxhomeke kakhulu emoyeni ukuze lwenze umsebenzi walo, futhi lokhu kusho ukuthi izinzwa zethu zidinga i-mitochondria ukusebenza kahle. Lapho i-mitochondria ihamba kahle, isimiso sezinzwa ngokuvamile siwukuqala ukuhlupheka.
Izimpawu zeMitochondrial Disease
Isifo esivame kakhulu esibangelwa yisifo se-mitochondrial yisimangalo, okusho isifo se-muscle.
Ezinye izimpawu ezingase zibe khona zihlanganisa izinkinga zombono, izinkinga zokucabanga, noma ukuhlanganiswa kwezimpawu. Izimpawu zivame ukubuthana ndawonye ukuze zenze enye ye-syndromes ehlukahlukene.
I-Ophthalmoplegia yangaphandle engapheliyo (i-CPEO) - ku-CPEO, imisipha yamehlo ikhubazekile kancane kancane. Lokhu kuvame ukuvela lapho abantu beseminyakeni yabo engamashumi amathathu, kepha kungenzeka kunoma yisiphi isikhathi. Umbono ophindwe kabili awuvamile, kodwa ezinye izinkinga ezibukwayo zingatholakala ngokuhlolwa kukadokotela. Ezinye izinhlobo, ikakhulu lapho zitholakala emindeni, zihambisana nezinkinga zokuzwa, izinkinga zokukhuluma noma zokugwinya, izinzwa ze-neuropathies , noma ukucindezeleka.
I-Kearns-Sayre syndrome - I-Kearns-Sayre syndrome cishe iyafana ne-CPEO, kodwa ngezinye izinkinga ezingaphezulu kanye nokuqala kokuqala. Izinkinga zivame ukuqala lapho abantu bengaphansi kweminyaka engama-20. Ezinye izinkinga zibandakanya i-retinopathy ye-pigmentary, i- cerebellar ataxia , izinkinga zenhliziyo nokulahlekelwa kwengqondo. I-Kearns-Sayre syndrome inonya ngaphezu kwe-CPEO, futhi ingaholela ekufeni ngeminyaka eyishumi yokuphila.
I-Leber Hereditary Optic Neuropathy (LHON) - I-LHON ifomu elilahlekelwe yifa lokulahlekelwa kombono elibangela ukuphuphutheka kumadoda amasha.
I-Leigh Syndrome - Eyaziwa nangokuthi i-necrotizing encephalometepathy, i-Leigh syndrome ngokuvamile ivela ezinganeni ezincane kakhulu. lesi sifo senza i-ataxia, ukugabha , ubuthakathaka, ukubambezeleka kokuthuthukiswa, i- dystonia , nokuningi. I-imagery resonance imaging (MRI) yobuchopho ibonisa isignali engavamile ku-basal ganglia. Isifo ngokuvamile sibulalayo phakathi nezinyanga.
Ukuxilongwa kwe-mitochondrial ne-lactic acidosis kanye neziqephu ezinjenge-episodes (MELAS) - I- MELAS ingenye yezinhlobo ezivame kakhulu zezifo zemitochondrial. Izuzwe njengefa. Lesi sifo sibangele iziqephu ezifana nezibhamu, ezingabangela ubuthakathaka noma ukulahleka kombono. Ezinye izimpawu zihlanganisa ukugubha, ukuguga, ukuhlanza, ukulahlekelwa kwezindlebe, ubuthakathaka bemisipha kanye nesimo esifushane. Isifo ngokuvamile siqala ebuntwaneni futhi sithuthuka ekudemeni kwengqondo. Ingatholakala ngezinga eliphezulu le-lactic acid egazini kanye nokubukeka kwe-fiber ebomvu obomvu ngaphansi kwe-microscope.
Isithuthwane se-myoclonic enezintambo ezibomvu ezigqamile (MERRF) - I-Myoclonus iyisisindo esishesha kakhulu, esifana nalokho abaningi abasanda kulala ngaphambi kokuba silale. I-myoclonus e-MERRF ivame kakhulu futhi ilandelwa ukuthunyeka, i-ataxia, nobuthakathaka bemisipha. Ukungazizwa, izinkinga zombono, ukuphazamiseka kwezinzwa ze-peripheral and dementia kungase kwenzeke futhi.
Izithulu zesifo somzimba nesifo sikashukela (i-MIDD) - Lesi sifo semithichondrial sithinta abantu abaneminyaka engama-30 kuya kwangu-40 ubudala. Ngaphandle kokulahlekelwa kokuzwa nesifo sikashukela, abantu abane-MIDD bangaba nokulahlekelwa kombono, ubuthakathaka bemisipha, izinkinga zenhliziyo, isifo sezinso, isifo somzimba kanye nesimo esifushane.
I-encephalopathy ye-Mitochondrial encephalopathy (MNGIE) - Lokhu kubangela ukungahambi kahle kwamathumbu, okungaholela ekucindezelekeni kwesisu nangomzimba. Izinkinga nokunyakaza kwamehlo nazo zivamile, njengoba izinzwa ze-neuropathies kanye nezindaba ezimhlophe zishintsha ebuchosheni. Isifo sifika kunoma yikuphi kusukela ebuntwaneni kuya emashumi amahlanu kodwa kuvame kakhulu ezinganeni.
I-neuropathy, i-ataxia ne-retinitis pigmentosa (i-NARP) - Ngaphandle kwezinkinga ze-neripheral ne-clumsiness, i-NARP ingabangela ukubambezeleka kokuthuthukiswa, isithuthwane, ubuthakathaka, nokucindezeleka komqondo.
Ezinye izifo ze-mitochondrial zihlanganisa i-Pearson syndrome (i-sideroblastic anemia kanye ne-pancreatic dysfunction), i-Barth syndrome (i-X-linked cardiomyopathy, i-mitochondrial myopathy, ne-neutropenia ye-cyclic), nokuphuza ukukhula, i-amino aciduria, i-cholestasis, ukugqama kwensimbi, i-lactic acidosis, nokufa kwangaphambili (GRACILE ).
Ukuthola izifo ze-Mitochondrial
Ngenxa yokuthi isifo se-mitochondrial singabangela ububanzi bezimpawu eziphazamisayo, lezi zinkinga zingase zibe nzima ngisho nodokotela abaqeqeshwe ukuba baqaphele. Esikhathini esingavamile lapho zonke izimpawu zibonakala ziyingqayizivele ngenxa yesifo esithile, ukuhlolwa kofuzo kungenziwa ukuqinisekisa ukuxilongwa. Kungenjalo, ezinye izivivinyo zingadingeka.
I-Mitochondria inesibopho se-aerobic metabolism, iningi lethu lisisebenzisa nsuku zonke ukuze sithuthe. Lapho umzimba we-aerobic uphelelwa amandla, njengokwenza umzimba ovivinya umzimba, umzimba unesimiso sokulondoloza esiholela ekwakheni i-lactic acid. Lesi yisisindo esenza imisipha yethu igule futhi ishise lapho sibacindezela isikhathi eside. Ngoba abantu abanesifo se-mitochondrial banamandla okunciphisa ukusebenzisa i-aerobic umzimba, i-lactic acid iyakha, futhi lokhu kungalinganiswa futhi kusetshenziswe njengesibonakaliso sokuthi kukhona okungahambi kahle nge-mitochondria. Ezinye izinto zingakhuphula i-lactate, noma kunjalo. Isibonelo, i-lactic acid e- cerebrospinal fluid ingaphakanyiswa ngemuva kokugubha noma ukushaya. Ngaphezu kwalokho, ezinye izinhlobo zezifo ze-mitochondrial, njenge-Leigh syndrome, zivame ukuba namazinga a-lactate angaphansi kwemingcele evamile.
Ukuhlola okuyisisekelo kungabandakanya amazinga e-lactate eplasma kanye nohlobo lwamakhemikhali. Ama-electrocardiograms angakwazi ukuhlolisisa ama-arrhythmias, angaba yingozi. Isithombe se-resonance (magnetic resonance image) (MRI) singabheka izinguquko zendaba ezimhlophe . I-Electromyography ingasetshenziselwa ukuphenya ngesifo se-muscle. Uma kukhona ukukhathazeka kokuqothulwa, i-electroencephalography ingalawulwa. Ngokuya ngezimpawu, ukuhlolwa kwe-audiology noma i-ophthalmology kungabuye kunconywe.
I-muscle biopsy ingenye yezindlela ezinokwethenjelwa kakhulu zokuthola ukukhathazeka kwe-mitochondrial. Izifo eziningi ze-mitochondrial ziza ne-myopathy, ngezinye izikhathi ngisho noma zingekho izimpawu ezibonakalayo ezifana nobuhlungu besisu noma ubuthakathaka.
Ukwelashwa kwezifo zeMitochondrial
Ngalesi sikhathi, alukho ukwelashwa okuqinisekisiwe kokuphazamiseka kwe-mitochondrial. Ukugxila ekulawuleni izimpawu njengoba bevela. Kodwa-ke, ukuxilongwa kahle kungasiza ukulungiselela ukuthuthukiswa kwesikhathi esizayo, kanti uma kwenzeka kugula ifa, kungathinta ukuhlela komndeni.
Isifingqo
Ngamafuphi, isifo se-mitochondrial kufanele sikhohlwe uma kunenhlanganisela yezimpawu ezibandakanya inhliziyo ye-muscle, ubuchopho noma amehlo. Ngenkathi ifa lomama libuye lisikisela, kungenzeka futhi livame ukuba nesifo se-mitochondrial siphumelele ekuguquleni kwe-DNA yenuzi, ngenxa yokusebenzisana phakathi kwezinto eziphilayo zohlobo lwe-nucleus kanye ne-mitochondria. Ngaphezu kwalokho, ezinye izifo zihamba kancane, okusho ukuthi zenzeka okokuqala ngaphandle kokuthola ifa. Izifo ze-mitochondrial zisabonakala zingavamile futhi zilawulwa kangcono ngugqirha onokuqonda okuqinile kwalesi sifo sesifo sezinzwa.
Imithombo
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