Insulin-Like Growth Factor 1 IGF-1 or insulin-like growth factor 1 (brand name: Increlex) is a growth factor which is very closely related to insulin. It carries the same amount of amino acids as insulin and responsible for the anabolic reactions to GH. IGF-1 is an important factor in childhood growth and is highly anabolic in adults. It is also known by the brand name Increlex and the generic name mecasermin.. IGF-1 (Insulin-Like Growth Factor 1)
IGF1, originally called somatomedin C, is a 70-amino acid polypeptide hormone. IGF1 is the major mediator of prenatal and postnatal growth. It is produced primarily in liver and serves as an endocrine (as well as paracrine and autocrine) hormone mediating the action of GH in peripheral tissues such as muscle, cartilage, bone, kidney, nerves, skin, lungs, and the liver itself. In the circulation IGF1 exists in a complex with IGF binding protein 3 (IGFBP3) and an acid-labile subunit (ALS). IGF1 deficiency follows an autosomal recessive mode of transmission. Currently, only four IGF1 mutations have been described, which leads to low or no IGF1 expression or impaired affinity to IGF1 receptors.
It is central to the somatotropic axis, acting downstream of growth hormone (GH). It activates both the mitogen-activated protein (MAP) kinase and PI3K signaling pathways, acting in almost every tissue in the body to promote tissue growth and maturation through upregulation of anabolic processes. Overall GH and IGF1 signaling falls with age, suggesting that it is this reduced IGF1 activity that leads to age-related changes in organisms. However, mutations that reduce IGF1-signaling activity can dramatically extend the lifespan of organisms.