Page 23 - Module 1-Anatomy and Physiology of Growth Hormone Function Final (Interactive)

Module 1: Anatomy and Physiology of Growth Hormone

The Somatopause

The term somatopause refers to the gradual and progressive decrease in GH
secretion that occurs normally with increasing age during adult life and that is
associated with an increase in adipose tissue and low-density lipoprotein (LDL)
levels and a decrease in lean body mass.
Figure 8 illustrates the sequence below:

• Changes in lifestyle and genetic predispositions promote accumulation of body
fat with aging.
• Increased GHBP levels associated with obesity reduce GH bioavailability.
• The increased body fat increases the availability of free fatty acids, which can
cause insulin resistance and high blood insulin levels.
• High insulin levels suppress the IGF-1 binding protein, resulting in an increase in
free IGF-I levels.
• Together, these factors suppress the release of GH from the pituitary gland,
which further increases fat mass.

Figure 8. Aging and release of GH

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