title: Leucine Promotes Proliferation and Differentiation of Primary Preterm Rat Satellite Cells in Part through mTORC1 Signaling Pathway.
abstract: Signaling through the mammalian target of rapamycin (mTOR) in response to leucine modulates many cellular and developmental processes. However, in the context of satellite cell proliferation and differentiation, the role of leucine and mTORC1 is less known. This study investigates the role of leucine in the process of proliferation and differentiation of primary preterm rat satellite cells, and the relationship with mammalian target of rapamycin complex 1 (mTORC1) activation. Dissociation of primary satellite cells occurred with type I collagenase and trypsin, and purification, via different speed adherence methods. Satellite cells with positive expression of Desmin were treated with leucine and rapamycin. We observed that leucine promoted proliferation and differentiation of primary satellite cells and increased the phosphorylation of mTOR. Rapamycin inhibited proliferation and differentiation, as well as decreased the phosphorylation level of mTOR. Furthermore, leucine increased the expression of MyoD and myogenin while the protein level of MyoD decreased due to rapamycin. However, myogenin expressed no affect by rapamycin. In conclusion, leucine may up-regulate the activation of mTORC1 to promote proliferation and differentiation of primary preterm rat satellite cells. We have shown that leucine promoted the differentiation of myotubes in part through the mTORC1-MyoD signal pathway.
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. daijm6639@foxmail.com.
authors.forename: Jie-Min
authors.initials: JM
authors.lastname: Dai
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. yumuxue@mail.sysu.edu.cn.
authors.forename: Mu-Xue
authors.initials: MX
authors.lastname: Yu
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. shenzhy@mail.sysu.edu.cn.
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Shen
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. guochuyi1990@foxmail.com.
authors.forename: Chu-Yi
authors.initials: CY
authors.lastname: Guo
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. zhuangsq@mail.sysu.edu.cn.
authors.forename: Si-Qi
authors.initials: SQ
authors.lastname: Zhuang
authors.affiliation: Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province 510080, China. qiuxsh@mail.sysu.edu.cn.
authors.forename: Xiao-Shan
authors.initials: XS
authors.lastname: Qiu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D007930:Leucine / Q000494:pharmacology*; D000076222:Mechanistic Target of Rapamycin Complex 1; D046912:Multiprotein Complexes / Q000378:metabolism*; D018485:Muscle Fibers, Skeletal; D018482:Muscle, Skeletal / Q000166:cytology / Q000187:drug effects*; D017570:MyoD Protein / Q000378:metabolism; D018008:Myogenin / Q000378:metabolism; D010766:Phosphorylation; D047928:Premature Birth; D017207:Rats, Sprague-Dawley; D032496:Satellite Cells, Skeletal Muscle / Q000187:drug effects* / Q000502:physiology; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D046912:Multiprotein Complexes; D017570:MyoD Protein; D018008:Myogenin; D000076222:Mechanistic Target of Rapamycin Complex 1; D058570:TOR Serine-Threonine Kinases; D007930:Leucine
keywords: MyoD; differentiation; leucine; mTOR; myogenin; preterm; proliferation; satellite cells