TY - JOUR
T1 - Methods for Accurate Assessment of Myofiber Maturity During Skeletal Muscle Regeneration
AU - Yoshimoto, Yuki
AU - Ikemoto-Uezumi, Madoka
AU - Hitachi, Keisuke
AU - Fukada, So Ichiro
AU - Uezumi, Akiyoshi
N1 - Funding Information:
We would like to thank Editage (www.editage.com) for English language editing. Funding. YY was funded by Grant-in-Aid for JSPS Research Fellows for FY2019 and The Japanese Society for Bone and Mineral Research Frontier Scientist Grant for FY 2019. MI-U was funded by JSPS KAKENHI Grant Number JP19K09614. AU was funded by JSPS KAKENHI Grant Number JP19H04063, The General Insurance Association of Japan, and Research Fund of Mitsukoshi Health and Welfare Foundation.
Funding Information:
YY was funded by Grant-in-Aid for JSPS Research Fellows for FY2019 and The Japanese Society for Bone and
Publisher Copyright:
© Copyright © 2020 Yoshimoto, Ikemoto-Uezumi, Hitachi, Fukada and Uezumi.
PY - 2020/4/22
Y1 - 2020/4/22
N2 - Adult skeletal muscle has a remarkable ability to regenerate. Regeneration of mature muscle fibers is dependent on muscle stem cells called satellite cells. Although they are normally in a quiescent state, satellite cells are rapidly activated after injury, and subsequently proliferate and differentiate to make new muscle fibers. Myogenesis is a highly orchestrated biological process and has been extensively studied, and therefore many parameters that can precisely evaluate regenerating events have been established. However, in some cases, it is necessary to evaluate the completion of regeneration rather than ongoing regeneration. In this study, we establish methods for assessing the myofiber maturation during muscle regeneration. By carefully comparing expression patterns of several muscle regeneration-related genes, we found that expression of Myozenin (Myoz1 and Myoz3), Troponin I (Tnni2), and Dystrophin (Dmd) is gradually increased as muscle regeneration proceeds. In contrast, commonly used regeneration markers such as Myh3 and Myh8 are transiently upregulated after muscle injury but their expression decreases as regeneration progresses. Intriguingly, upregulation of Myoz1, Myoz3 and Tnni2 cannot be achieved in cultured myotubes, indicating that these markers are excellent indicators to assess myofiber maturity. We also show that analyzing re-expression of Myoz1 and dystrophin in individual fiber during regeneration enables accurate assessment of myofiber maturity at the single-myofiber level. Together, our study provides valuable methods that are useful in evaluating muscle regeneration and the efficacy of therapeutic strategies for muscle diseases.
AB - Adult skeletal muscle has a remarkable ability to regenerate. Regeneration of mature muscle fibers is dependent on muscle stem cells called satellite cells. Although they are normally in a quiescent state, satellite cells are rapidly activated after injury, and subsequently proliferate and differentiate to make new muscle fibers. Myogenesis is a highly orchestrated biological process and has been extensively studied, and therefore many parameters that can precisely evaluate regenerating events have been established. However, in some cases, it is necessary to evaluate the completion of regeneration rather than ongoing regeneration. In this study, we establish methods for assessing the myofiber maturation during muscle regeneration. By carefully comparing expression patterns of several muscle regeneration-related genes, we found that expression of Myozenin (Myoz1 and Myoz3), Troponin I (Tnni2), and Dystrophin (Dmd) is gradually increased as muscle regeneration proceeds. In contrast, commonly used regeneration markers such as Myh3 and Myh8 are transiently upregulated after muscle injury but their expression decreases as regeneration progresses. Intriguingly, upregulation of Myoz1, Myoz3 and Tnni2 cannot be achieved in cultured myotubes, indicating that these markers are excellent indicators to assess myofiber maturity. We also show that analyzing re-expression of Myoz1 and dystrophin in individual fiber during regeneration enables accurate assessment of myofiber maturity at the single-myofiber level. Together, our study provides valuable methods that are useful in evaluating muscle regeneration and the efficacy of therapeutic strategies for muscle diseases.
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U2 - 10.3389/fcell.2020.00267
DO - 10.3389/fcell.2020.00267
M3 - Article
AN - SCOPUS:85084250026
VL - 8
JO - Frontiers in Cell and Developmental Biology
JF - Frontiers in Cell and Developmental Biology
SN - 2296-634X
M1 - 267
ER -