Isihloko
I-methylene blue ne-ALS: kungani imiphumela ihluka phakathi kwamamodeli okuhlola
Uma usesha i-methylene blue ne-ALS, uthola izimangalo ezimbili ezibonakala ziphikisana. Esinye sithi udayi oluhlaza wavikela amaseli ezinzwa kumamodeli e-ALS. Esinye sithi awenzanga lutho egundaneni eliyimodeli ye-ALS. Zombili izimangalo zicaphuna amaphepha ocwaningo angempela, futhi womabili amaphepha kufanele athathwe ngokungathí sina. Lokhu kuphikisana kuyaphela uma ucacisa umqondo osemuva kokuhlola ngakunye: imodeli iyona echaza isimangalo.
Umphumela osesikelemwini uyisimangalo esiphathelene nesikelemu. Umphumela osenhlanzini esesigabeni sesibungu uyisimangalo esiphathelene nenhlanzi ekuleso sigaba. Akukho kulokhu okuyisimangalo ngesiguli kuze kube yilapho ucwaningo lwenkambo yesifo esilwaneni esincelisayo lukusekela. Lesi sihloko siqhathanisa amaphepha amabili acashunwa kakhulu ukuze ubone ukuthi kungani izimpendulo zawo zihlukile.
Ukuhlola okubili kuthebula elilodwa
Gcina leli thebula livuliwe njengoba ufunda. Wonke umehluko obalulekile phakathi kwalezi zifundo uqukethwe kulo.
| I-TDP-43 ne-FUS ezikelemwini nasezinhlanzini | I-SOD1 egundaneni | |
|---|---|---|
| Iphepha locwaningo | UVaccaro nozakwabo, 2012, ku-PLoS ONE | ULougheed noTurnbull, 2011, ku-PLoS ONE |
| Isidalwa | Isikelemu esiyindilinga i-C. elegans nezibungu ze-zebrafish | Igundane le-congenic elinamakhophi amaningi e-SOD1 G93A yomuntu |
| Ufuzo lwe-ALS olulingiswayo | I-TDP-43 yomuntu eguqukile (A315T ezikelemwini, G348C ezinhlanzini) ne-FUS eguqukile (S57Δ ezikelemwini, R521H ezinhlanzini) | I-SOD1 G93A yomuntu eguqukile, eyimbangela ye-ALS ezuzwa ngofuzo emndenini |
| Ukuchayeka | Ukuchayeka ngokucwiliswa: 6 noma 60 μM ezitsheni zokukhulisa kusukela ekuchanyuselweni, 600 μM ekuhloleni kwesikhashana okwenziwa oketshezini, 30 kuya ku-60 μM ubusuku bonke emibungwini yezinhlanzi | Cishe 25 mg/kg ngosuku ngomlomo ku-gelatin enongiwe, nsuku zonke kusukela eminyakeni yobudala yezinsuku ezingu-45 kuze kube sesigabeni sokugcina |
| Imiphumela elinganisiwe | Ukukhubazeka kokunyakaza, ukonakala kwezandiso zamaseli ezinzwa alawula ukunyakaza, ukuhlolwa kwama-synapse, ukubhukuda kwezinhlanzi nokuma kwama-axon, izilinganiso zokucindezeleka okubangelwa yi-oxidation | Isikhathi kuze kuqale izimpawu zezinzwa, ubude bezigaba zesifo ezihlelwe ngokulandelana, ukuphila kuze kufike esigabeni sokugcina esichaziwe, isisindo somzimba |
| Umphumela oyinhloko | Ukubuyiselwa okubanzi kokunyakaza nokwakheka kwamaseli ezinzwa | Akukho ukubambezeleka okubalulekile ngokwezibalo ekuqaleni kwesifo sekukonke, futhi akukho ukwelulwa kokuphila okubalulekile ngokwezibalo |
Ufuzo luhlukile, izinhlobo zezilwane zihlukile, indlela yokunikeza umthamo ihlukile, isikhathi sihlukile, nemiphumela elinganisiwe ihlukile. Uhlobo lofuzo lumane luwumehluko owodwa kwemihlanu, ngakho lezi zifundo ezimbili azikwazi ukufakazela ukuthi i-methylene blue isebenza ngokukhetha indlela eyodwa ye-ALS. Zifakazela into enomkhawulo omncane kodwa esawusizo: ukubuyiselwa okunamandla ngesikhathi sokuchayeka okuqondile kusenesikhathi kumamodeli alula akuzange kubonakale enkambweni yesifo esilwaneni esincelisayo esasithola umuthi ngomlomo isikhathi eside.
Umphumela omuhle: okwaboniswa ucwaningo lwezikelemu nezinhlanzi
Ucwaningo lwezikelemu nezinhlanzi lwango-2012 lwabangela ukukhiqizwa kwe-TDP-43 noma i-FUS yomuntu eguqukile kumaseli ezinzwa ezikelemu alawula ukunyakaza, lwaphinde lwajova i-mRNA yomuntu eguqukile emibungwini yezinhlanzi. Lawa ngamamodeli obuthi bamaprotheni. Akhiqiza kabusha imiphumela enobuthi yeprotheni eguqukile ekunyakazeni nasekumeni kwamaseli ezinzwa phakathi kwezinsuku, hhayi yonke inkambo ye-ALS yomuntu omdala ethatha iminyaka.
Ukwelashwa kwaqala kusenesikhathi kakhulu. Izikelemu zakhula ku-agar ene-methylene blue kusukela ekuchanyuselweni. Imibungu yezinhlanzi yahlala esixazululweni somuthi ubusuku bonke kusukela emahoreni angu-24 ngemva kokuvundiswa, ukuziphatha kwayo kwahlolwa cishe ezinsukwini ezimbili kamuva. Umgoqo phakathi kwegazi nobuchopho wawungekho phakathi komuthi neseli lezinzwa ngendlela oba khona ngayo esilwaneni esincelisayo, futhi akukho zinga lomuthi elakalwa ku-plasma noma ebuchosheni.
Ngaphansi kwalezo zimo, imiphumela yayimikhulu futhi ingaguquguquki. Kokubili u-6 no-60 μM kwanciphisa ukukhubazeka kokunyakaza okuhambisana nokukhula ngeminyaka ezikelemwini ze-TDP-43 ne-FUS. Ngosuku lwe-12 lokuba zindala, cishe amaphesenti angu-80 ezikelemu ze-TDP-43 ezingelashwanga ayengakwazi ukunyakaza, uma kuqhathaniswa namaphesenti angaba ngu-10 ezikelemu ezazelashwe kusukela ekuchanyuselweni. Ukuhlolwa kwama-synapse nakho kwakhomba ngakule ndlela: izikelemu ze-TDP-43 zazizwela ngokweqile ku-aldicarb, umuthi ohlola ukudluliswa kwezimpawu phakathi kwezinzwa nemisipha, futhi i-methylene blue yabuyisela impendulo ngasohlangothini lwesimo esivamile. Amanani ezandiso zamaseli ezinzwa alawula ukunyakaza ezazonakala ehla, umphumela ucace kakhulu ku-60 μM. Ezinhlanzini, ukubhukuda okubangelwa ukuthintwa kwaba ngcono kakhulu, futhi ama-axon amafushane alawula ukunyakaza aphinde akhula asondela ebudeni obuvamile ku-30 noma 60 μM, nakuba ukubuyiselwa kwakuyingxenye kuphela kunokuba kuphelele.
Idatha yokucindezeleka okubangelwa yi-oxidation ihambisana nencazelo yokusebenza njenge-antioxidant. Izikelemu nezinhlanzi ezinokuguquka kofuzo zabonisa izilinganiso eziphakeme zezinhlobo zomoya-mpilo ezisabela kalula, ezabe zehla lapho kwelashwa. Izikelemu ezivamile ezazithola i-methylene blue zaphila isikhathi eside kakhulu lapho zichayeke entweni ekhuthaza i-oxidation kunalezo ezingelashwanga. Kodwa kunemikhawulo emibili ebalulekile. Amazinga esewonke amaprotheni e-TDP-43 ne-FUS aguqukile awazange ehle, futhi ucwaningo aluzange lulinganise ngokuqondile izinqwaba zamaprotheni anqwabelene. Ngakho lubonisa ukubuyiselwa kokusebenza ngaphandle kokufakazela ukususwa kwalezo zinqwaba. Noma ubani olandela indlela imibono ye-redox neyama-mitochondria evame ukuchazwa ngayo kufanele abheke indlela yokusebenza njengokuthile okusekelwayo kodwa okungakaqinisekiswa ngokuphelele.
Isikhathi sokuqala sasiyimininingwane eyayifundisa kakhulu. Lapho ababhali belinda kwaze kwaba usuku lwesi-5 lokuba izikelemu zindala ukuze baqale ukwelapha, izinga lokukhubazeka kokunyakaza ngosuku lwe-12 lalicishe libe amaphesenti angu-55, esikhundleni samaphesenti angaba ngu-10 ngokwelashwa okuqala ekuchanyuselweni. Umuthi ofanayo, isikelemu esifanayo, ukuguquka kofuzo okufanayo, kodwa umphumela omncane kakhulu. Ukuchayeka kusenesikhathi ngenhloso yokuvimbela yikho okwakubangela ingxenye enkulu yenzuzo eyayibonakala.
Umphumela ongabonisanga inzuzo: okwaboniswa ucwaningo lwegundane le-SOD1
Ucwaningo lwamagundane lwango-2011 lwabuza umbuzo onzima kakhulu ohlelweni oluqinile kakhulu. Amagundane e-congenic e-SOD1 G93A adlulela ekuthuthumeleni kwezitho zangemuva, ekuphazamisekeni kokuhamba, nasekulahlekelweni ikhono lokuzibuyisela endaweni efanele aze afinyelele ephuzwini lokugcina elinqunywe kusengaphambili. Ukwelashwa kwaqala ngaphambi kwezimpawu ngosuku lwama-45 futhi kwaqhubeka nsuku zonke, ababukeli behlola isimo sezinzwa ngesikali esisuka ku-0 kuya ku-6. Lokhu ukuhlola yonke inkambo yesifo, okwenza kusondele kakhulu kulokho isiguli esingakukhathalela kunanoma yiliphi ijika lokukhubazeka kokunyakaza esikelemwini.
Imiphumela eyinhloko ayizange ibonise inzuzo. Ukuqala kwesifo sekukonke kwenzeka ezinsukwini ezingu-121 eqenjini lokuqhathanisa, uma kuqhathaniswa nezinsuku ezingu-124 nge-methylene blue, umehluko ongabalulekile ngokwezibalo. Ukuphila kuze kube sesigabeni sokugcina kwakuyizinsuku ezingu-167 uma kuqhathaniswa nezingu-170, nakho kungabalulekile ngokwezibalo. Ukuhlaziya okumbalwa kwemiphumela yesibili kwavuna ukwelashwa: ezinsikazi zabonisa ukubambezeleka kokuqala kwesifo kwezinsuku ezingaba ngu-7, futhi izilwane ezelashiwe zachitha isikhathi esithe xaxa ezigabeni ezithambile nesincane ezigabeni ezinzima. Njengoba amaqembu amancane ahlukaniswe ngobulili ayenamalungu ambalwa futhi kwenziwa ukuqhathanisa okuningi kwezigaba, leyo miphumela kufanele ibhekwe njengokukhiqiza imibono yokuhlolwa kunokuba ibe ubufakazi. Akuzange kubalwe amaseli ezinzwa, kuhlolwe ukunqwabelana kwe-SOD1, noma kukalwe izimpawu ze-oxidation noma zokuvuvukala. Ngakho ucwaningo futhi alukwazi ukusho ukuthi umuthi wafinyelela lapho wawuqondiswe khona kodwa wehluleka, noma awuzange nhlobo uthinte lezo zinhloso kulo mthamo. Kwahlolwa umthamo owodwa kuphela.
Ababhali ngokwabo bagqamisa umkhawulo ojule kakhulu, osebenza kuzo zombili izinhlangothi. I-SOD1 G93A enamakhophi amaningi ilingisa kahle isifo esibangelwa ubuthi be-SOD1, kodwa isifo se-SOD1 siyingxenye encane ye-ALS ezuzwa ngofuzo emndenini futhi sinebhayoloji ehlukile kweyeningi lesifo esivela ngaphandle kwephethini yokuzuzwa emndenini. Basikisela ukuphinda kuhlolwe izinto ezingaba yimithi kumamodeli ezilwane ezincelisayo asekelwe ku-TDP-43. Leso siphakamiso sesiyinkimbinkimbi kakhulu, ngoba ababhali bocwaningo lwezikelemu nezinhlanzi baphawula ukuthi ucwaningo oluhlukile lwe-methylene blue kumagundane e-TDP-43 nalo lwahluleka ukwenza imiphumela yokunyakaza ibe ngcono. Ngakho into ingabonakala inamandla ohlelweni olulodwa lwe-TDP-43 kodwa ingabi nomphumela kolunye uhlelo lwe-TDP-43. Uhlelo lubaluleke njengofuzo.
Kungani ukuthuthuka esikelemwini noma enhlanzini kungenakufakazela inzuzo ezigulini
Cabanga ngemodeli ngayinye njengephendula umbuzo ohlukile.
Okokuqala, ibhayoloji ihlukile. I-TDP-43 ne-FUS ngamaprotheni abopha ama-nucleic acid futhi anokusebenzelana kofuzo okufanayo kulezi zinhlelo ezilula, kuyilapho ubuthi be-SOD1 busebenza ngezindlela eziseduze nomsuka wenkinga ezihluke ngokwengxenye. Umuthi onciphisa uhlobo olulodwa lokucindezeleka okubangelwa ubuthi bamaprotheni awudingeki ukuba unciphise olunye. Impumelelo ekulweni nokukhiqizwa ngokweqile kwamaprotheni embungwini nayo ayidingeki ukuba ibikezele impumelelo ekulweni nokonakala kancane kwamaseli ezinzwa kumuntu omdala, okuhambisana nokuvuvukala, ukubandakanyeka kwamaseli e-glia, nokwehla kwesimo somzimba wonke.
Okwesibili, ukuchayeka kuhlukile. Ukuchayeka okuqhubekayo ngokucwiliswa emazingeni e-micromolar akufani nokunikezwa umthamo ngomlomo. Ukumuncwa emathunjini, ukucutshungulwa komuthi lapho uqala ukudlula emzimbeni, ukubopha kumaprotheni e-plasma, ukungena ebuchosheni, nokususwa emzimbeni konke kuphakathi komthamo ogwinyiwe neseli lezinzwa elisemgogodleni elilawula ukunyakaza. Alukho kulezi zifundo olwalinganisa amazinga omuthi ohlelweni lwezinzwa, ngakho alukho olungaxhumanisa izinga lalo nelolunye.
Okwesithathu, isikhathi sihlukile. Izinzuzo ezikelemwini nasezinhlanzini zazincike kakhulu ekwelashweni ngaphambi kokuba kunqwabelane izinguquko zesifo. Ukwelashwa kwamagundane nakho kwaqala ngaphambi kwezimpawu, okuwuphawu oluhle locwaningo, kodwa ukwelashwa kwabantu cishe ngaso sonke isikhathi bekungaqala ngemva kokuqala kwezimpawu, okuyisikhathi esisekamuva nakakhulu. Uphawu lwenzuzo yokuvimbela ekuhlolweni kombungu kwezinsuku ezimbili luyisiqalo socwaningo, hhayi imodeli yokusetshenziswa ekwelapheni iziguli.
Okwesine, imiphumela elinganisiwe ihlukile. Ukukhubazeka kokunyakaza ezinsukwini ezingu-12, ukuzwela ku-aldicarb, ubude be-axon ngama-micrometer, nebanga lokubhukuda yizici ezibonakalayo eziseduze nenqubo ehlolwayo. Ukuqala kwesifo nokuphila esilwaneni esincelisayo kuhlanganisa zonke izinqubo zomzimba ezinxephezela noma ezenza isimo sibe yinkimbinkimbi. Imithi ivame ukushintsha izilinganiso eziseduze nenqubo ehlolwayo ngaphandle kokushintsha isikhathi sokuphila. Yingakho kusetshenziswa izilinganiso zesikhathi kuze kwenzeke isigameko ezilwaneni ezincelisayo.
Abafundi abafuna uhlu lokuhlola isihloko esikhulu esilandelayo bangalusebenzisa oluvela kokuthi indlela yokufunda izifundo zangaphambi kokuhlolwa kubantu: buza ngohlobo lwesilwane, ufuzo olufakiwe, umthamo nendlela yokuwunikeza, ukuthi amazinga omuthi akalwa yini, ukuthi ukwelashwa kwaqala nini uma kuqhathaniswa nezinguquko zesifo, ukuthi umphumela olinganisiwe wawuyisici esibonakalayo sesikhathi esifushane noma inkambo yesifo, nokuthi umphumela waphindwa yini kwelinye ilabhorethri. Ubufakazi obubanzi nge-methylene blue kubantu buhlala buyindawo yokuhlola ukuthi ikhona yini yalezi zimpawu zokuqala eyagcina ithuthuke yaba idatha yokwelashwa kweziguli.
Lokhu kusho ukuthini ezigulini nasemindenini
Awekho amalungiselelo amisiwe okusebenzisa i-methylene blue ku-ALS avela kula maphepha. Ucwaningo oluhle lusekela olunye ucwaningo ngezindlela ze-oxidation nezama-synapse kubhayoloji ye-TDP-43 ne-FUS. Ucwaningo olungabonisanga inzuzo luphikisana nokulindela ukuguqulwa kwenkambo yesifo ngokunikezwa umuthi ngomlomo isikhathi eside kuleli zinga lokuchayeka esifweni sohlobo lwe-SOD1. Ndawonye, achaza ukungahambisani kwemiphumela phakathi kwamamodeli, hhayi isincomo sokwelapha.
Ukuphepha kufanele kuchazwe ngendlela eqaphile efanayo nokusebenza komuthi. Izifundo ze-ALS emagundaneni azisho lutho ngomthamo ophephile kubantu, futhi i-methylene blue inezingozi zangempela ngokubhidlika kwamangqamuzana abomvu egazi uma kune-G6PD enganele, nangobuthi be-serotonin lapho ihlanganiswa nemithi ethinta i-serotonin. Ukusola ukushoda kwe-G6PD, ukusetshenziswa kwamanje kwemithi yokucindezeleka, nanoma yiluphi ushintsho oluhleliwe emithini kufanele kuxoxwe nochwepheshe wezokwelapha. Kufanele kubuyekezwe futhi idatha evamile yokuphepha kwe-methylene blue ngaphambi kokuba noma ubani athathe isinyathelo ngenxa yezihloko ezinkulu ezivela elabhorethri.
Iphuzu eliyinhloko lingachazwa ngomusho owodwa. I-methylene blue yabangela ukubuyiselwa okunamandla kwezici ezibonakalayo ezikelemwini nasezinhlanzini ezisesigabeni sezibungu ze-TDP-43 ne-FUS ngokuchayeka kusenesikhathi, futhi cishe ayilethanga nzuzo ekuqaleni kwesifo noma ekuphileni ocwaningweni lwamagundane e-SOD1 anikezwa umuthi ngomlomo isikhathi eside; ngakho incazelo ethembekile ukuthi lobu bufakazi buncike kumodeli futhi abusekeli ukusetshenziswa ezigulini.