TY - JOUR
T1 - Bidirectional myofiber transition through altering the photobiomodulation condition
AU - Lin, Chuang Yu
AU - Niwa, Akira
AU - Hou, Chun Yin
AU - Tsai, Chung Min
AU - Chang, Hsi
N1 - Funding Information:
We thank Dr. Geng-Chang Yeh and You-Shan Lin for their comments and suggestions during the preparation of the manuscript. We thank Chung-Min Tsai for complementing the description of the PBM. This study was supported by Grant-in-Aid for Scientific Research TMU100-AE1-B10 , 101TMU-TMUH-11 from Taipei Medical University and Taipei Medical University Hospital and Grant-in-Aid for Scientific Research 101-2314-B-038-017-MY3 from the Ministry of Science and Technology, Taiwan (R.O.C.) .
Publisher Copyright:
© 2020 Elsevier B.V.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/11
Y1 - 2020/11
N2 - Despite remarkable advancements in modern medicine, muscular atrophy remains as an unsolved problem. It is well known that pathological characteristics of different atrophy types could vary according to the pathophysiological causes. In fact, the lesion of atrophy is not always homogenously distributed but often predominantly evident in either fast or slow myofibers. As the focalization of the atrophic lesions, the existence and the functional impairment of each fast and slow progenitor/satellite cell (SC) are suspected though there are still controversies about this hypothesis. In this study, we isolated Pax7 positive (Pax7+ve) SCs from the tibia anterior (fast) and soleus (slow) muscles respectively and successfully demonstrated, for the first time, the difference between optimal exposure durations of photobiomodulation (PBM) which was known as low level laser irradiation (LLLI) in promoting proliferation of Pax7+ve SC which were acquired from fast and slow muscles respectively. Moreover, a hypertrophy-accompanied bidirectional change in myofiber composition with neuromuscular junction alteration, either from slow to fast or fast to slow, were achieved by applying different PBM durations. Simultaneously, PBM exhibited a synergistic effect with muscle exercise on the increase in myofiber size. Our data suggested the existence of at least two different populations of Pax7+ve SC which possess distinct sensitivities towards PBM. As our data revealed the capability of PBM in bidirectional changes of skeletal muscle composition and neuromuscular junction constitution thereby strengthen its contractility through altering the irradiation condition, we believe PBM showed the potential to be as a promising clinical treatment for muscular atrophy.
AB - Despite remarkable advancements in modern medicine, muscular atrophy remains as an unsolved problem. It is well known that pathological characteristics of different atrophy types could vary according to the pathophysiological causes. In fact, the lesion of atrophy is not always homogenously distributed but often predominantly evident in either fast or slow myofibers. As the focalization of the atrophic lesions, the existence and the functional impairment of each fast and slow progenitor/satellite cell (SC) are suspected though there are still controversies about this hypothesis. In this study, we isolated Pax7 positive (Pax7+ve) SCs from the tibia anterior (fast) and soleus (slow) muscles respectively and successfully demonstrated, for the first time, the difference between optimal exposure durations of photobiomodulation (PBM) which was known as low level laser irradiation (LLLI) in promoting proliferation of Pax7+ve SC which were acquired from fast and slow muscles respectively. Moreover, a hypertrophy-accompanied bidirectional change in myofiber composition with neuromuscular junction alteration, either from slow to fast or fast to slow, were achieved by applying different PBM durations. Simultaneously, PBM exhibited a synergistic effect with muscle exercise on the increase in myofiber size. Our data suggested the existence of at least two different populations of Pax7+ve SC which possess distinct sensitivities towards PBM. As our data revealed the capability of PBM in bidirectional changes of skeletal muscle composition and neuromuscular junction constitution thereby strengthen its contractility through altering the irradiation condition, we believe PBM showed the potential to be as a promising clinical treatment for muscular atrophy.
KW - Bidirectional myofiber transition
KW - Low-level laser
KW - Neuromuscular junction
KW - Synergic hypertrophic effect
UR - http://www.scopus.com/inward/record.url?scp=85091636968&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85091636968&partnerID=8YFLogxK
U2 - 10.1016/j.jphotobiol.2020.112041
DO - 10.1016/j.jphotobiol.2020.112041
M3 - Article
C2 - 33002778
AN - SCOPUS:85091636968
SN - 1011-1344
VL - 212
JO - Journal of Photochemistry and Photobiology B: Biology
JF - Journal of Photochemistry and Photobiology B: Biology
M1 - 112041
ER -