World J Mens Health.  2019 Jan;37(1):19-30. 10.5534/wjmh.180018.

Growth Hormone and Aging: Updated Review

• Bartke A

• KMID: 2429719
• DOI: http://doi.org/10.5534/wjmh.180018

Abstract

Role of growth hormone (GH) in mammalian aging is actively explored in clinical, epidemiological, and experimental studies. The age-related decline in GH levels is variously interpreted as a symptom of neuroendocrine aging, as one of causes of altered body composition and other unwelcome symptoms of aging, or as a mechanism of natural protection from cancer and other chronic diseases. Absence of GH signals due to mutations affecting anterior pituitary development, GH secretion, or GH receptors produces an impressive extension of longevity in laboratory mice. Extension of healthspan in these animals and analysis of survival curves suggest that in the absence of GH, aging is slowed down or delayed. The corresponding endocrine syndromes in the human have no consistent impact on longevity, but are associated with remarkable protection from age-related disease. Moreover, survival to extremely old age has been associated with reduced somatotropic (GH and insulin-like growth factor-1) signaling in women and men. In both humans and mice, elevation of GH levels into the supranormal (pathological) range is associated with increased disease risks and reduced life expectancy likely representing acceleration of aging. The widely advertised potential of GH as an anti-aging agent attracted much interest. However, results obtained thus far have been disappointing with few documented benefits and many troublesome side effects. Possible utility of GH in the treatment of sarcopenia and frailty remains to be explored.

Keyword

Aging; Growth hormone; Healthy aging; Life expectancy; Somatotropin

MeSH Terms

Acceleration
Aging*
Animals
Body Composition
Chronic Disease
Female
Growth Hormone*
Humans
Life Expectancy
Longevity
Male
Mice
Sarcopenia
Growth Hormone

Figure

• 

  Fig. 1 Key mechanisms mediating the effects of reduced growth hormone (GH) signaling on aging and longevity (↓decrease, ↑increase). IGF-1: insulin-like growth factor-1, mTORC1: mechanistic target of rapamycin complex 1.

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