I-Amyloid Cascade Hypothesis yezifo ze-Alzheimer's?

Abanye abacwaningi bakholelwa ukuthi i-amyloid ehlasela i-hypothesis iyichaza kahle imbangela yesifo se-Alzheimer .

Nakuba imibuzo eminingi ingakaphenduliwe, i-amyloid ihlasela i-hypothesis iphakamisa ukuthi ukuqoqwa ngokweqile kwe-peptide okuthiwa i- amyloid-beta yisenzakalo esiyinhloko esibhedlela se-Alzheimer: Lokhu kuqoqa kubeka uchungechunge lwezenzakalo eziholela ekufeni kwezingqamuzana zobuchopho, futhi ekugcineni, Isifo se-Alzheimer's.

Indlela i-Amyloid-Beta engayenza ngayo i-Alzheimer's

I-Amyloid-beta ikhiwa kusukela kumaprotheni amakhulu okuthiwa i-amyloid precurrent protein (APP). Abacwaningi abazi kahle umsebenzi we-APP okwamanje, kepha kungathinta umsebenzi wamaseli obuchopho. Ama-enzyme akhethekile (okuthiwa i-secretase) anqume le phrotheni ezindaweni ezithile, kanti omunye wemikhiqizo yalesi "cleavage" yi-peyde-amyloid-beta. Lezi peptide ze-amyloid-beta zihlangana ndawonye kulokho okubizwa ngokuthi ama-oligomers, futhi ngokusho kwe-amyloid cascade hypothesis, yiwo ama-oligomeri ayenobuthi emangqamuzanini obuchopho, abangela izinkinga zakuqala zokucabanga ezinesifo se-Alzheimer. Kamuva, lawa ma-oligomers enza amapulethi afana nesifo se-Alzheimer, kodwa yi-oligomers - ngokungafani nama-plaques-yiwo angamakhemikhali anobuthi.

Ngenkathi kunezingqikithi eziningi zobufakazi obusekela i-amyloid ehlasela i-hypothesis, kunezinselelo eziningi kuye.

Okokuqala, i-amyloid-beta eqoqa emaceleni ivela ekugugeni okujwayelekile kanye nesifo se-Alzheimer's. Kwesinye, ama-deposits omunye amaprotheni abizwa ngokuthi ama-tau amafomu ama- tangles ahambisana kangcono nezinkinga zokucatshangelwa ezifweni ze-Alzheimer kunama-plaques. Okokugcina, kunezinye izinkomba ezihlukile, njenge-mitochondrial cascade hypothesis, eziye zahlongozwa njengezincazelo zezimbangela zesifo se-Alzheimer.

Umthombo:

Christensen DD. Isifo se-Alzheimer: inqubekela phambili ekuthuthukiseni izifo ezilwa namagciwane-ukuguqula izifo zokwelapha. I-CNS Spectr. 2007; 12: 113-123.

-I-athikili Ehlelwe ngu-Esther Heerema, MSW