{"id":47878,"date":"2024-02-25T00:29:34","date_gmt":"2024-02-24T23:29:34","guid":{"rendered":"https:\/\/www.infokuryr.cz\/n\/?p=47878"},"modified":"2024-02-24T19:47:06","modified_gmt":"2024-02-24T18:47:06","slug":"prulomova-studie-nasla-prvni-dukazy-o-prenosu-alzheimerovy-choroby-z-cloveka-na-cloveka","status":"publish","type":"post","link":"https:\/\/www.infokuryr.cz\/n\/2024\/02\/25\/prulomova-studie-nasla-prvni-dukazy-o-prenosu-alzheimerovy-choroby-z-cloveka-na-cloveka\/","title":{"rendered":"Pr\u016flomov\u00e1 studie na\u0161la prvn\u00ed d\u016fkazy o p\u0159enosu Alzheimerovy choroby z \u010dlov\u011bka na \u010dlov\u011bka"},"content":{"rendered":"
<\/div>\n

Ned\u00e1vn\u00e1\u00a0<\/span>studie<\/span><\/a>\u00a0zjistila, \u017ee Alzheimerova choroba se m\u016f\u017ee \u0161\u00ed\u0159it z \u010dlov\u011bka na \u010dlov\u011bka n\u00e1hodnou kontaminac\u00ed sav\u010d\u00edch prion\u016f b\u011bhem ur\u010dit\u00fdch l\u00e9ka\u0159sk\u00fdch nebo chirurgick\u00fdch z\u00e1krok\u016f.<\/span><\/p>\n

Sav\u010d\u00ed priony jsou infek\u010dn\u00ed proteiny, kter\u00e9 se \u0161\u00ed\u0159\u00ed v mozku a zp\u016fsobuj\u00ed smrteln\u00e1 neurodegenerativn\u00ed onemocn\u011bn\u00ed.<\/span><\/p>\n

\u201eNenazna\u010dujeme t\u00edm, \u017ee se m\u016f\u017eete nakazit Alzheimerovou chorobou.\u00a0Nen\u00ed to p\u0159enosn\u00e9 ve smyslu virov\u00e9 nebo bakteri\u00e1ln\u00ed infekce \u0161\u00ed\u0159en\u00e9 vzduchem,\u201c<\/span><\/em>\u00a0objas\u0148uje spoluautor studie Dr.\u00a0John Collinge, neurolog a \u0159editel Institutu pro medic\u00ednsk\u00fd v\u00fdzkum prion\u016f (Medical Research Council Prion) na University College London (UCL).<\/span><\/p>\n

\u201eStane se to jen tehdy, kdy\u017e se lidem n\u00e1hodn\u011b podaj\u00ed nitro\u017eiln\u011b \u2013 v podstat\u011b lidskou tk\u00e1n\u00ed nebo extrakty lidsk\u00e9 tk\u00e1n\u011b obsahuj\u00edc\u00edmi prionov\u00e9 z\u00e1rodky, co\u017e je na\u0161t\u011bst\u00ed velmi vz\u00e1cn\u00e1 a neobvykl\u00e1 okolnost.\u201c<\/span><\/em><\/p>\n

V nov\u00e9 studii publikovan\u00e9 v recenzovan\u00e9m l\u00e9ka\u0159sk\u00e9m \u010dasopise\u00a0<\/span>Nature Medicine<\/span><\/em>\u00a0Collinge a jeho kolegov\u00e9 z\u00a0<\/span>Institutu pro medic\u00ednsk\u00fd v\u00fdzkum prion\u016f<\/span><\/em>\u00a0uvedli, \u017ee v\u00edce ne\u017e 1800 pacient\u016f ve Velk\u00e9 Brit\u00e1nii dostalo lidsk\u00fd r\u016fstov\u00fd hormon extrahovan\u00fd z hypof\u00fdz mrtv\u00fdch t\u011bl mezi lety 1859.<\/span><\/p>\n

R\u016fstov\u00fd hormon se pou\u017e\u00edv\u00e1 k l\u00e9\u010db\u011b n\u011bkter\u00fdch zdravotn\u00edch stav\u016f, v\u010detn\u011b nedostatku r\u016fstov\u00e9ho hormonu u d\u011bt\u00ed a dosp\u011bl\u00fdch.<\/span><\/p>\n

Studie prok\u00e1zala, jak l\u00e9\u010dba lidsk\u00fdm r\u016fstov\u00fdm hormonem transplantovala toxick\u00e9 proteiny do d\u011bt\u00ed a zp\u016fsobila u nich rozvoj Alzheimerovy choroby v mlad\u00e9m v\u011bku.<\/span><\/p>\n

P\u0159ibli\u017en\u011b 25 let od konce 50. let 20. stolet\u00ed se lidsk\u00fd r\u016fstov\u00fd hormon z\u00edsk\u00e1van\u00fd z mrtv\u00fdch t\u011bl (CHGH) sporadicky pou\u017e\u00edval k l\u00e9\u010db\u011b d\u011bt\u00ed s ur\u010dit\u00fdmi probl\u00e9my fyzick\u00e9ho v\u00fdvoje.\u00a0Hormon byl odeb\u00edr\u00e1n z hypof\u00fdzy mrtv\u00fdch lid\u00ed a injek\u010dn\u011b pod\u00e1v\u00e1n d\u011btem s neobvykle n\u00edzk\u00fdm vzr\u016fstem.<\/span><\/p>\n

V pr\u016fb\u011bhu let se u neo\u010dek\u00e1van\u011b vysok\u00e9ho procenta d\u011bt\u00ed l\u00e9\u010den\u00fdch CHGH vyvinul neurodegenerativn\u00ed stav zvan\u00fd Creutzfeldt-Jakobova choroba (CJD), co\u017e je rychle progresuj\u00edc\u00ed a v\u017edy smrteln\u00e1 neurodegenerativn\u00ed porucha.<\/span><\/p>\n

P\u0159edpokl\u00e1d\u00e1 se, \u017ee je zp\u016fsobena abnorm\u00e1ln\u00ed izoformou zn\u00e1m\u00e9ho bun\u011b\u010dn\u00e9ho glykoproteinu zn\u00e1m\u00e9ho tak\u00e9 jako prionov\u00fd protein.<\/span><\/p>\n

Auto\u0159i studie poznamenali, \u017ee tato praxe byla zak\u00e1z\u00e1na v roce 1985 kv\u016fli s\u00edl\u00edc\u00edm d\u016fkaz\u016fm spojuj\u00edc\u00edm CHGH s Creutzfeldt-Jakobovou chorobou (CJD), kdy\u017e v\u00fdzkumn\u00edci objevili, \u017ee n\u011bkter\u00e9 vzorky CHGH obsahovaly toxick\u00fd prion v m\u00edst\u011b neurodegenerativn\u00edho onemocn\u011bn\u00ed ve zdrav\u00fdch mozc\u00edch.<\/span><\/p>\n

Lidsk\u00fd r\u016fstov\u00fd hormon byl n\u00e1sledn\u011b rychle nahrazen \u201ebezpe\u010dn\u011bj\u0161\u00ed syntetickou verz\u00ed\u201c.<\/span><\/p>\n

\u201eKontaminovan\u00fd\u201c hormon zodpov\u011bdn\u00fd za p\u0159enos Alzheimerovy choroby<\/span><\/h2>\n

Zp\u016fsob, jak\u00fdm se prionov\u00e1 Creutzfeldt-Jakobova nemoc \u0161\u00ed\u0159ila z \u010dlov\u011bka na \u010dlov\u011bka, podn\u00edtil v\u00fdzkumn\u00edky, aby prozkoumali, zda se i Alzheimerova choroba m\u016f\u017ee p\u0159en\u00e1\u0161et mezi lidmi.<\/span><\/p>\n

N\u00e1sledn\u00e1 studie zjistila, \u017ee n\u011bkter\u00e9 vzorky CHGH obsahovaly nahromad\u011bn\u00ed amyloidn\u00edch beta protein\u016f.\u00a0<\/span>Studie na zv\u00ed\u0159atech<\/span><\/a>\u00a0z roku 2019 publikovan\u00e1 ve v\u011bdeck\u00e9m \u010dasopise\u00a0<\/span>Scientific Reports<\/span><\/em>\u00a0odhalila, \u017ee u my\u0161\u00ed, kter\u00fdm byl pod\u00e1v\u00e1n kontaminovan\u00fd r\u016fstov\u00fd hormon, se vyvinuly p\u0159\u00edznaky rozv\u00edjej\u00edc\u00ed se Alzheimerovy choroby.<\/span><\/p>\n

V tomto bod\u011b v\u00fdzkumn\u00edci navrhli, \u017ee lze p\u0159edpokl\u00e1dat p\u0159enos Alzheimerovy choroby z \u010dlov\u011bka na \u010dlov\u011bka, ale st\u00e1le pot\u0159ebovali n\u011bjak\u00fd solidn\u00ed d\u016fkaz.\u00a0Pak se pod\u00edvali na osm pacient\u016f, kte\u0159\u00ed byli ned\u00e1vno odesl\u00e1ni na N\u00e1rodn\u00ed prionovou kliniku Lond\u00fdn\u011b s neurologick\u00fdmi probl\u00e9my.<\/span><\/p>\n

P\u011bti z osmi pacient\u016f l\u00e9\u010den\u00fdch hormonem CHGH v d\u011btstv\u00ed \u2013 nyn\u00ed ji\u017e ve v\u011bku od 38 do 55 let \u2013 byl diagnostikov\u00e1n \u010dasn\u00fd n\u00e1stup demence, ale zat\u00edm nevykazovaly \u017e\u00e1dn\u00e9 patologick\u00e9 p\u0159\u00edznaky Creutzfeldt-Jakobovy choroby.<\/span><\/p>\n

V\u0161ech p\u011bt z t\u011bchto pacient\u016f spl\u0148ovalo krit\u00e9ria diagn\u00f3zy\u00a0<\/span>Alzheimerovy choroby<\/span><\/a>\u00a0, ale nevykazovaly \u017e\u00e1dn\u00e9 zn\u00e1mky genetick\u00e9 predispozice k brzk\u00e9mu n\u00e1stupu t\u00e9to nemoci okr\u00e1daj\u00edc\u00ed \u010dlov\u011bka o pam\u011b\u0165.<\/span><\/p>\n

V\u00fdzkumn\u00edci proto nazna\u010dili, \u017ee Alzheimerova choroba, podobn\u011b jako Creutzfeldt-Jakobova choroba, m\u00e1 \u201eenvironment\u00e1ln\u011b z\u00edskan\u00e9 iatrogenn\u00ed formy v d\u016fsledku \u010dinnosti l\u00e9ka\u0159e nebo terapie\u201c (nap\u0159. l\u00e9\u010dba kontaminovan\u00fdm hormonem hypof\u00fdzy, jako\u017e i sporadick\u00fd nebo \u010dasn\u00fd n\u00e1stup zd\u011bd\u011bn\u00fdch forem).<\/span><\/p>\n

V\u011bdci napsali, \u017ee \u201ea\u010dkoli iatrogenn\u00ed (l\u00e9ka\u0159sk\u00fdm \u00fakonem vyvolan\u00e1) Alzheimerova choroba m\u016f\u017ee b\u00fdt vz\u00e1cn\u00e1, neexistuje \u017e\u00e1dn\u00fd n\u00e1znak, \u017ee by se amyloid beta protein mohl p\u0159en\u00e1\u0161et mezi jednotlivci prost\u0159ednictv\u00edm b\u011b\u017en\u00fdch ka\u017edodenn\u00edch aktivit.\u201c<\/span><\/p>\n

\u201eZji\u0161t\u011bn\u00ed zvy\u0161uj\u00ed d\u016fle\u017eitost opat\u0159en\u00ed, jako je nap\u0159\u00edklad zaji\u0161t\u011bn\u00ed \u00fa\u010dinn\u00e9 dekontaminace chirurgick\u00fdch n\u00e1stroj\u016f,\u201c<\/span><\/em>\u00a0\u0159ekl Collinge.<\/span><\/p>\n

Profesor biochemie z Manchestersk\u00e9 univerzity Andre Doig uvedl:<\/span><\/p>\n

\u201eZat\u00edmco nov\u00fd typ Alzheimerovy choroby, o kter\u00e9 se zde p\u00ed\u0161e, je velmi zaj\u00edmav\u00fd z v\u011bdeck\u00e9ho hlediska \u2013 jeliko\u017e odhaluje nov\u00fd zp\u016fsob \u0161\u00ed\u0159en\u00ed nemoci \u2013 nen\u00ed d\u016fvod se toho b\u00e1t, proto\u017ee p\u0159\u00ed\u010dina nemoci byla zastavena p\u0159ed v\u00edce ne\u017e 40 lety.\u00a0P\u0159enos nemoci z jednoho lidsk\u00e9ho mozku do druh\u00e9ho by se t\u00edmto zp\u016fsobem u\u017e nikdy nem\u011bl opakovat.\u201c<\/span><\/em><\/p>\n

(Souvisej\u00edc\u00ed: Dr. Michael Nehls\u00a0<\/span>navrhuje<\/span><\/a>\u00a0sjednocenou teorii Alzheimerovy choroby (UTAD) k prevenci a l\u00e9\u010db\u011b demence.)<\/span><\/p>\n

\u201eV sou\u010dasnosti pacienti dost\u00e1vaj\u00ed syntetick\u00e9 alternativy r\u016fstov\u00e9ho hormonu, kter\u00e9 byly schv\u00e1leny z hlediska bezpe\u010dnosti a nep\u0159edstavuj\u00ed riziko p\u0159enosu nemoc\u00ed,\u201c<\/span><\/em>\u00a0uvedl v prohl\u00e1\u0161en\u00ed p\u0159idru\u017een\u00fd \u0159editel v\u00fdzkumu a inovac\u00ed Alzheimerovy spole\u010dnosti Dr.\u00a0Richard Oakley.<\/span><\/p>\n

Ujistil ve\u0159ejnost, \u017ee dne\u0161n\u00ed zp\u016fsoby l\u00e9\u010dby byly vyvinuty tak, aby minimalizovaly riziko jak\u00e9koli p\u0159enosn\u00e9 nemoci.<\/span><\/p>\n

\u201eZ\u00e1sadn\u00ed je, \u017ee neexistuje \u017e\u00e1dn\u00fd d\u016fkaz o tom, \u017ee by se Alzheimerova choroba mohla p\u0159en\u00e1\u0161et v kontextu ka\u017edodenn\u00edch aktivit nebo b\u011b\u017en\u00e9 zdravotn\u00ed p\u00e9\u010de,\u201c<\/span><\/em>\u00a0poznamenal Oakley.<\/span><\/p>\n

(Pozn\u00e1mka redakce: A co tak transfuze krve od d\u00e1rc\u016f o\u010dkovan\u00fdch proti Covid-19, nakolik se prok\u00e1zalo, \u017ee hrotov\u00fd protein vytv\u00e1\u0159en\u00fd t\u011blem o\u010dkovance na z\u00e1klad\u011b gen\u016f z vakc\u00edny obsahuje sekvence prion\u016f?)<\/span><\/p>\n

Z\u00e1v\u011br<\/span><\/h2>\n

Dal\u0161\u00ed podobn\u00e9 \u010dl\u00e1nky naleznete na str\u00e1nce\u00a0<\/span>Alzheimers.news<\/span><\/a>\u00a0.<\/span><\/p>\n

V\u00edce podrobnost\u00ed o prvn\u00edm d\u016fkazu p\u0159enosu Alzheimerovy choroby z \u010dlov\u011bka na \u010dlov\u011bka se dozv\u00edte v n\u00e1sleduj\u00edc\u00edm\u00a0<\/span>videu<\/span><\/a>\u00a0(v angli\u010dtin\u011b):<\/span><\/p>\n