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Effects of Myostatin on Nuclear Morphology at the Myotendinous Junction

Hikari Amemiya1, Masahito Yamamoto2, Kazunari Higa3

  • 1Division of Special Needs Dentistry and Orofacial Pain, Department of Oral Health and Clinical Science, Tokyo Dental College, 2-9-18 Kandamisaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan.

International Journal of Molecular Sciences
|April 13, 2023
PubMed

Insights

Myostatin (Myo) influences the myotendinous junction (MTJ) after injury. This protein impacts cell shape and may strengthen connections during healing and growth.

Area of Science:

  • Muscle and Tendon Biology
  • Connective Tissue Research
  • Regenerative Medicine

Background:

  • Myostatin (Myo) is a known regulator of skeletal muscle growth.
  • Recent findings suggest Myo also plays a role in maintaining tendon health.
  • The specific function of Myo at the myotendinous junction (MTJ) remains unclear.

Purpose of the Study:

  • To investigate the role of Myostatin (Myo) in the myotendinous junction (MTJ).
  • To examine Myo's involvement in both in vivo and in vitro models of tendon injury and healing.

Main Methods:

  • Analyzed cell accumulation and nuclear morphology in mouse Achilles tendons post-injury.
  • Quantified Myostatin (Myo) expression levels at different time points after injury.
  • Utilized a pseudo MTJ model using myoblast (C2C12) and fibroblast (NIH3T3) cell sheets in vitro.

Main Results:

  • Observed significant changes in nuclear shape and aspect ratio on the tendon side of the MTJ between postoperative days 7 and 28.
  • Found a significant increase in Myostatin (Myo) expression at the MTJ by postoperative day 28 compared to day 7.
  • In vitro, Myostatin (Myo) altered the nuclear morphology of scleraxis-positive cells at the myoblast-fibroblast boundary, without affecting key muscle or tendon development markers.

Conclusions:

  • Myostatin (Myo) expression increases at the MTJ during tendon healing.
  • Myostatin (Myo) influences nuclear morphology in cells at the MTJ interface.
  • Myostatin (Myo) may contribute to strengthening the MTJ during initial growth and wound healing phases.
Keywords:
Achilles tendon injuryC2C12NIH3T3myostatinmyotendinous junction

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