Catch-up growth: cellular and molecular mechanisms

Area of Science:

• Mammalian physiology
• Developmental biology
• Growth regulation

Background:

• Body growth in mammals typically slows and ceases with age due to specific physiological mechanisms.
• Periods of growth inhibition are often followed by a compensatory growth phase exceeding normal rates, termed catch-up growth.

Purpose of the Study:

• To investigate the underlying physiological mechanisms driving catch-up growth in mammals.
• To understand how prior growth inhibition influences subsequent growth trajectories and tissue proliferation.

Main Methods:

• The study reviews recent evidence and proposes a mechanistic explanation for catch-up growth.
• Focuses on the role of delayed physiological aging and retained tissue proliferative capacity.

Main Results:

• Growth inhibition delays the onset of age-related growth cessation mechanisms.
• Tissues maintain enhanced proliferative capacity post-inhibition, leading to accelerated growth.
• This mechanism supports catch-up growth in both body length (growth plate proliferation) and organ mass (nonskeletal tissue proliferation).

Conclusions:

• Catch-up growth is facilitated by the preservation of tissue proliferative potential due to delayed aging signals.
• This mechanism explains accelerated growth in length and organ mass following growth inhibition.