Growth Hormone As Antiaging Factor in Old Bones

Area of Science:

• Gerontology
• Bone Biology
• Endocrinology

Background:

• Aging is associated with decreased growth hormone (GH) levels, potentially contributing to age-related bone changes.
• The GH/insulin-like growth factor-I (IGF-I) axis plays a crucial role in bone metabolism and health.
• The use of GH administration in aged individuals for bone health remains a subject of debate.

Purpose of the Study:

• To investigate the effects of systemic GH treatment on bone properties, metabolism, and bone mineral density (BMD) in aged rats.
• To evaluate GH's impact on biomechanical strength and bone turnover markers in elderly rats.

Main Methods:

• Aged Wistar rats were administered GH (2 mg/kg/day) for 10 weeks.
• Measurements included plasma osteocalcin, IGF-I, carboxy-terminal telopeptide of type I collagen, cross-sectional bone area, BMD, and femur biomechanical properties (three-point bending test).
• Statistical analysis was performed using a t-test, with significance set at p < 0.05.

Main Results:

• GH treatment significantly increased bone area, BMD (by 11%), bone flexural modulus, stiffness, and ultimate load in aged rats.
• Plasma levels of osteocalcin and IGF-I were significantly elevated in the GH-treated group.
• Bone resorption markers remained unchanged, while cortical bone area showed a relative decrease.

Conclusions:

• Systemic GH administration in old rats enhanced biomechanical bone properties, BMD, and markers of bone formation (IGF-I, osteocalcin).
• GH treatment positively impacted bone health in aged rats, suggesting its potential as a therapeutic strategy for age-related bone decline.
• Further research is warranted to explore the long-term effects and clinical applicability of GH therapy for bone health in aging populations.