Analysis Note

The biological activty is measured in a serum-free cell proliferation assay using the human breast carcinoma cell line, MCF-7.

Application

Insulin-like Growth Factor-I from mouse has been used:for the preparation of growth factor cocktailas a media supplement for mouse embryonic fibroblasts culture as a media supplement to serve as a positive control to investigate the effects of Angelica sinensis on myotubes

Biochem/physiol Actions

Potent mitogenic growth factor that mediates the growth-promoting activities of growth hormone postnatally. Mouse and human IGF-I share 97% sequence identity.

Insulin-like growth factor I (IGF-I) plays critical roles in cellular energy metabolism and in growth and development, especially prenatal growth.IGF-I is secreted from the liver into circulation in a process regulated by pituitary growth hormone (GH) and so it mediates the growth-promoting activity of GH. After birth IGF-I expression in most extrahepatic tissues declines and hepatic expression of IGF-I becomes GH-regulated. Expression of IGF-I outside the liver is regulated differently, depending on the specific tissues. For example, gonadotropins and sex steroids regulate IGF-I expression within the reproductive system, while parathyroid hormone and sex steroids regulate IGF-I expression in bone. IGF-I is produced in several human tumors. IGF-I is mitogenic for a variety of cells including fibroblasts, osteoblasts, smooth muscle cells, fetal brain cells, neuroglial cells, and erythroid progenitor cells. IGF-I exerts its actions exclusively through the IGF-I receptor (IGF-IR). IGF-I induces endothelial cell migration and is involved in the regulation of angiogenesis.

General description

Insulin-like growth factor I (IGF-I) belongs to the insulin-like growth factor (IGF; see MIM 147440) family of signaling molecules. IGF-I is also known as somatomedin. In the developing embryo IGF-I is expressed primarily by mesenchymal-derived cells.

Packaging

50 µg in glass insert

Physical form

Lyophilized from a 0.2 µm filtered solution in phosphate buffered saline.