Kodi Genetics of Aging Key to Cancer?
Maselo onse ali ndi moyo wopangidwa ndi mapulogalamu omwe amapangidwa, amachulukitsa, ndipo pamapeto pake amatha kugwiritsira ntchito apoptosis (selo imfa) pamene sagwiranso ntchito.
Nthawi zambiri zimathandiza kulingalira za kubwezeretsa ma makina monga makina ojambula akale: pamene selo limasintha lokha, zimakhala zovuta kwambiri komanso zimasintha fanolo. M'kupita kwa nthaŵi, maselo a selo ( DNA ) amayamba kugwedezeka ndipo selo lokha limakhala chenicheni chapachiyambi.
Izi zikachitika, maselo omwe amamangidwa ndi maselo amachititsa selo yatsopano kuthana ndikusunga machitidwewo.
Chiwerengero cha nthawi yomwe selo lingathe kugawa chimadalira chodabwitsa chomwe chimatchedwa malire a Hayflick. Izi zikutanthauzira zomwe zimachitika kuti magawano (otchedwa mitosis) apitirize kuwonongera ma genetic, makamaka mbali ya DNA yotchedwa telomere.
Mzere wa Hayflick umanena kuti selo yambiri imagawanitsa pakati pa 50 mpaka 70 musanayambe kujambula.
Kumvetsa Telomeres
Chromosomes ndi makina onga ulusi omwe ali mkati mwa khungu la selo. Chromosome iliyonse imapangidwa ndi mapuloteni komanso molekyu imodzi ya DNA.
Pamapeto onse a chromosome ndi telomere yomwe anthu nthawi zambiri amawayerekezera ndi nsonga za pulasitiki kumapeto kwa nsapato. Ma telomeres ndi ofunika chifukwa amachititsa kuti ma chromosome asatuluke, kugwirana wina ndi mnzake, kapena kusakanikirana mu mphete.
Nthawi iliyonse selo likamagawanika, DNA yophatikizidwa kawiri imagawanika kuti chidziwitso cha majini chilembedwe.
Izi zikachitika, DNA yolembera imatchulidwa koma si telomere. Ngati bukuli lidzatha ndipo mitosis ikuyamba, malo omwe selo limatulutsidwa pa telomere.
Momwemo, ndi mbadwo uliwonse wa selo, telomere imakhala yofupikitsa ndi yofupika mpaka iyo sitingathe kukhalabe okhulupirika ku chromosome.
Ndiyomwe apo apoptosis imapezeka.
Telomeres 'Za Kukalamba ndi Khansa
Asayansi angagwiritse ntchito kutalika kwa telomere kudziwa zaka za selo ndi zowonjezera zambiri zomwe zasintha. Pamene magulu a magulu akulephereka, amawonongeka mofulumira monga senescence , omwe timakonda kutchula kuti akukalamba . Maselo a senescence akufotokoza chifukwa chake ziwalo zathu ndi matenda athu amayamba kusintha pamene tikukula. Mapeto ake, maselo athu onse ndi "akufa" ndipo amawoneka kuti ndi ofunika .
Zonse, ndiko, koma chimodzi. Maselo a khansa ndi mtundu umodzi wa selo umene ungathenso kukhala "wosafa." Mosiyana ndi maselo ofiira, maselo a khansa samayendetsedwa ndi selo koma amapitiriza kuwonjezeka popanda mapeto.
Izi, mkati mwazokha, zimasokoneza kuchuluka kwa kubwereza kwa maselo m'thupi. Ngati mtundu umodzi wa selo umaloledwa kubwereza kusatsekedwa, umatha kuchotseratu ena onse ndi kusokoneza ntchito zamoyo. Izi ndi zomwe zimachitika ndi khansara ndi chifukwa chake maselo "osakhoza kufa" angayambitse matenda ndi imfa.
Amakhulupirira kuti khansa imapezeka chifukwa chakuti kusintha kwa maselo kungayambitse kupanga puloteni, yotchedwa telomerase , yomwe imaletsa ma telomere kuti asafupikitse.
Ngakhale selo iliyonse m'thupi ili ndi ma genetic coding kuti ipangitse telomerase, maselo ena okha amafunikira izo.
Maselo a umuna, mwachitsanzo, amafunika kuti asiye kuchepetsa telomere kuti apange makopi oposa 50 okha; mwinamwake, kutenga mimba sikungakhoze kuchitika konse.
Ngati matenda obwera chifukwa cha chibadwa amachititsa kuti maselo a telomerase apangidwe, amachititsa kuti maselo osadziwika azichulukana ndikupanga zotupa. Zimakhulupirira kuti pamene chiwerengero cha moyo chikupitirirabe kukula, mwayi woterewu umachitika sikuti udzangowonjezereka koma potsiriza sadzatha.
> Chitsime;
> Arai, Y ;; Martin-Ruiz, C .; Takayama, M. et al. "Kutupa, Koma Osati Telomere Kutalika, Amalosera Kukalamba Kwambiri Pa Ukalamba Wambiri: Kuphunzira Kwambiri Kwambiri Kwambiri." e BioMedicine . 2015; 2 (10): 1549-48; DOI: 10.1016 / j.ebiom.2015.07.029 ..