Impembelelo ye-Hypertrophic yokunyamezela ukuSebenza kunye neendlela ezinokwenzeka

Ukuzilolonga, okanye "ukuzilolonga nge-aerobic", kudla ngokujongwa njengokuzivocavoca kwentliziyo kwaye akuqhelekanga kunxulunyaniswa noxinzelelo lwemisipha yamathambo. Ukuzilolonga kuchazwa njengokusebenzisa umthwalo ophantsi kwimisipha ixesha elide, njengesiphumo sokubaleka kwimisipha yethole kodwa kukwabandakanya nokusetyenziswa kobunzima obuphantsi kumthambo wokuxhathisa . Nangona kunjalo, uphando lwakutshanje, olucacisa izifo zemisipha yamathambo kwiimpuku ezinesifo seswekile, lufumanise isiphumo se-hypertrophic somthambo wokuzilolonga (kule meko, i-treadmill ebaleka kwimisipha ye-gastrocnemius), kwanakwiimpuku ezingengowesifo seswekile. Lukwachaza iiproteni ezimbini zemisipha yamathambo, iKinesin Family Member 5B (KIF5B) kunye neGrowth Associated Protein 43 (GAP-43), ukungasebenzi kakuhle kwazo kwisifo seswekile kunye nendlela umthambo wokuzilolonga okhuthaza ngayo uxinzelelo lwemisipha yamathambo ngezi ndlela zithile zeproteni.

Kolu phononongo, iimpuku ezingama-52 ezingamadoda zahlulwe zangamaqela ama-4: ezilawulayo (ezisempilweni, ezingenaso isifo seswekile), ezilawulayo eziqeqeshwe ukunyamezela, ezinesifo seswekile, eziqeqeshwe ukunyamezela. I-K1F5B, i-GAP-43 kunye ne-PAX7 (iiseli zesathelayithi zemisipha ezinoxanduva lokuvuselela izihlunu emva komonakalo wezihlunu obangelwe kukuzilolonga ² ), kunye nendawo ye-gastrocnemius cross-sectional area (CSA) zibalwe.

Iqela labantu abanesifo seswekile abangaqeqeshwanga lalinomlinganiselo ophantsi kakhulu we-gastrocnemius CSA xa kuthelekiswa iqela labantu abangaqeqeshwanga, kwaye phantse isiqingatha senani lee-muscle nuclei (myonuclei) kunye nesinye kwisithathu se-satellite cell (PAX7) yobuninzi beqela labantu abangaqeqeshwanga. Oku kubonisa izifo eziphambili kwimisipha yamathambo yabantu abanesifo seswekile. Nangona kunjalo, iqela labantu abaqeqeshwayo besifo seswekile lalinomlinganiselo ongcono kakhulu wempilo yemisipha , kwaye lalinomlinganiselo ofanayo we-CSA, myonuclei kunye ne-PAX7 njengolawulo olungaqeqeshwanga, nto leyo ebonisa isiphumo esibalulekileyo se-hypertrophic sokuqeqesha umsipha ngokunyamezela kunye nokukwazi ukunyanga izifo zemisipha ezibangelwa sisifo seswekile. Abalawuli abasempilweni abaqeqeshweyo babenomlinganiselo ophezulu kakhulu wemisipha kunawo onke amanye amaqela, kunye nobuninzi be-CSA ephezulu, kunye ne-myonuclei kunye ne-PAX7.

Iproteni ye-KIF5B yayinxulumene kakuhle kakhulu nenani le-myonuclei kunye ne-CSA yemisipha. I-KIF5B yayicinezelwe kancinci kwisifo seswekile kwaye uqeqesho lokunyamezela lwandise kakhulu iproteni. I-KIF5B kukholelwa ukuba inoxanduva lokubeka i-myonuclei kwimisipha (imisipha inee-nuclei ezininzi ngokungafaniyo nezinye iintlobo zeeseli kwaye i-myonuclei entsha inokwenziwa nakubantu abadala ngeendlela ezifana nomthambo wokuxhathisa ³ ). Ngaphezu koko, iproteni ye-GAP-43 nayo yayinxulumene kakuhle nenani le-myonuclei kunye ne-CSA yemisipha. I-GAP-43 nayo yayicinezelwe kancinci kwisifo seswekile kwaye uqeqesho lokunyamezela lwandise kakhulu iproteni. I-GAP-43 kukholelwa ukuba ibandakanyeka kulawulo lokuphathwa kwe-calcium. Ke ngoko, ukwandiswa kweeproteni zombini kwindawo ethile kwimisipha ye-gastrocnemius ngoqeqesho lokunyamezela kwemisipha kubonakala ngathi kubonelela ngempembelelo ye-hypertrophic, mhlawumbi ngezi ndlela zeproteni kwaye olu phando lukwakhanyisa nezizathu ezinokubakho zokungasebenzi kakuhle kwemisipha yamathambo ezifana nokuwohloka okubonwa kwizigulana zeswekile.

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Iingxelo:  

1. I-Rahmati, M., Taherabadi, SJ 2021. Imiphumo yoqeqesho lokuzivocavoca kwi-Kinesin kunye ne-GAP-43 ibonakaliso kwi-skeletal muscle fibers ye-STZ-induced diabetic rats. Sci Rep 11, 9535. https://doi.org/10.1038/s41598-021-89106-6 

2. Sambasivan R, Yao R, et al 2011. I-Pax7-ebonisa iiseli zesathelayithi ziyimfuneko ekuvuseleleni imisipha yabantu abadala. Uphuhliso. 2011 Sep;138(17):3647-56. doi: https://doi.org/10.1242/dev.067587 . I-Erratum kwi: Uphuhliso. 2011 Okt;138(19):4333. PMID: 21828093. 

3. UBruusgaard JC, uJohansen IB, okqhubekayo 2010. I-Myonuclei efunyenwe ngokuzilolonga ngokugqithisileyo yandulela i-hypertrophy kwaye ayilahlekanga ekunciphiseni. Iinkqubo zeNational Academy of Sciences Aug 2010, 107 (34) 15111-15116; DOI: https://doi.org/10.1073/pnas.0913935107  

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