A kind of IGF

The Human IGF-I is mitogenic polypeptide growth factors that stimulate the proliferation and survival of various cell types including muscle, bone, and cartilage tissue in vitro. Human IGF-I is predominantly produced by the liver, although a variety of tissues produce the Human IGF-I at distinctive times. The Human IGF-I belong to the Insulin gene family, which also contains insulin and relaxin. The Human IGF-I is similar by structure and function to insulin, but have a much higher growth-promoting activity than insulin.