IGF

(noun)

A hormone similar in molecular structure to insulin. It plays an important role in childhood growth and continues to have anabolic effects in adults. A synthetic analog of IGF-1, mecasermin is used for the treatment of growth failure.

Related Terms

Examples of IGF in the following topics:

  • Hormonal Regulation of Growth

    • Body growth is controlled by growth hormone (GH), produced by the anterior pituitary, and IGF-1, whose production is stimulated by GH.
    • GH also stimulates, through another pathway, the production of insulin-like growth factor 1 (IGF-1), a hormone homologous to proinsulin.
    • The liver, a major target organ of GH for this process, is the principal site of IGF-1 production.
    • IGF-1 has growth-stimulating effects on a wide variety of tissues.
    • IGF-1 also has stimulatory effects on osteoblast and chondrocyte activity to promote bone growth.

  • Aging and the Endocrine System

    • Somatopause is a term used to describe the change in GH/IGF-I axis, which involves a decrease in production and sensitivity to GH and IGF-I.
    • Decreases in IGF-I signaling, GH deficiency, and GH resistance cause delayed aging and extended lifespan in animal models, in sharp contrast to the effects of GH/IGF-I in humans.
    • The reason for the opposing actions of GH/IGF-I in different species is not presently understood.
    • In addition to lower circulating amounts of IGF-I, the responsiveness of bone to this protein has been shown to decrease in animal models.
    • This can be attributed to a decrease in IGF-I signaling pathways with advanced cell age.

  • Liver Function

    • The liver also produces the insulin-like growth factor 1 (IGF-1), a polypeptide protein hormone that plays an important role in childhood growth and continues to have anabolic effects in adults.

  • Bone Remodeling

    • Both processes utilize cytokine (TGF-β, IGF) signaling.

  • Stages of Bone Development

    • Both processes utilize cytokine (TGF-β, IGF) signalling.

  • Hair and Hormones

    • Increased levels of Insulin Growth Factor-1 (IGF-1) have been correlated to vertex balding.

  • Pituitary Gland Disorders

    • Once the effector glands produce sufficient hormones (thyroxine, cortisol, estradiol or testosterone and IGF-1), both the hypothalamus and the pituitary cells sense their abundance and reduce their secretion of stimulating hormones.