Insulin-like growth factors

Definition

Insulin-like growth factors (IGFs) are hormones that play a critical role in regulating growth and metabolism throughout the body. These proteins, primarily IGF-1 and IGF-2, are similar in structure to insulin and are produced mainly in the liver in response to growth hormone stimulation. They facilitate various biological processes, including cell growth, development, and differentiation, making them essential for normal physical growth and metabolic regulation.

5 Must Know Facts For Your Next Test

1. IGF-1 is primarily responsible for promoting systemic body growth, while IGF-2 has a more significant role during fetal development.
2. The production of IGFs is stimulated by growth hormone, but they also have independent effects on tissues.
3. IGFs circulate in the blood bound to specific binding proteins that regulate their activity and availability.
4. Imbalances in IGF levels can lead to disorders such as gigantism or dwarfism, highlighting their importance in normal growth.
5. IGFs also play a role in regulating metabolism by influencing insulin sensitivity and glucose uptake in cells.

Review Questions

• How do insulin-like growth factors interact with growth hormone to regulate body growth?
  • Insulin-like growth factors (IGFs) are largely produced in response to growth hormone stimulation from the pituitary gland. When growth hormone is released into the bloodstream, it prompts the liver and other tissues to synthesize IGFs. These IGFs then promote cell division and growth in various tissues, acting as mediators of the effects of growth hormone. This interaction ensures that the body's growth processes are synchronized and effectively regulated.
• Discuss the role of insulin-like growth factors in metabolic regulation beyond their function in promoting growth.
  • Insulin-like growth factors (IGFs) not only facilitate physical growth but also play a significant role in metabolic regulation. They enhance insulin sensitivity, which helps cells utilize glucose more efficiently. By promoting glucose uptake and influencing lipid metabolism, IGFs contribute to overall energy balance within the body. This dual role illustrates how IGFs connect growth with metabolic health, emphasizing their importance beyond just development.
• Evaluate the implications of abnormal insulin-like growth factor levels on health outcomes and disease states.
  • Abnormal levels of insulin-like growth factors (IGFs) can have significant implications for health. Elevated IGF-1 levels are associated with increased risks of certain cancers due to enhanced cell proliferation, while low levels may lead to issues such as stunted growth or metabolic disorders. Understanding these connections helps highlight how maintaining appropriate IGF levels is crucial for health. Consequently, monitoring IGF levels could provide valuable insights into an individual's risk for various diseases and conditions.

Related terms

Growth Hormone: A hormone secreted by the pituitary gland that stimulates growth, cell reproduction, and regeneration in humans and other animals.

Somatomedins: Another name for insulin-like growth factors, emphasizing their role in mediating the effects of growth hormone on tissues.

Receptors: Proteins located on cell surfaces that bind to hormones like IGFs, triggering specific cellular responses essential for growth and metabolism.