Insulin-like growth factors (IGFs) protect neurons, are important for oligodendrocyte survival and myelin production, and stimulate the proliferation of astrocytes. The effects of IGFs are regulated by a family of IGF binding proteins (IGFBPs). Astrocytes express predominantly IGFBP-2. In the present study, primary neonatal rat astrocytes were cultivated in a chemically defined medium to initia...

IGF-binding proteins (IGFBPs) and their proteases regulate IGFs bioavailability in multiple tissues. Pregnancy-associated plasma protein A (PAPP-A) is a protease acting by cleaving IGFBP2, 4, and 5, regulating local bioavailability of IGFs. We have previously shown that IGFs and IGFBPs are produced by human adult cardiac progenitor cells (haCPCs) and that IGF-1 exerts paracrine therapeutic effe...

Insulin-like growth factors (IGFs) have 6 types of binding proteins (IGFBPs), and IGFBP-3 is the major IGFBP in human sera. A proteolytic enzyme for IGFBP-3 has recently been reported to be present in human and animal pregnant sera. Although the physiological significance of a pregnancyassociated IGFBP-3 protease remains to be established, the proteolysis could result in lowering the affinity f...

Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in bone mass during adult life. Despite the rarity of HCAO, understanding the mediator(s) of the skeletal disease is of great interest. The IGFs-I and -II have potent anabolic effects on bone, and alterations in the IGFs and/or IGF-binding proteins (IGFBPs) could be responsible for the increase in...

Insulin-like growth factors (IGFs) and insulin are known to be mitogenic to a variety of cell types, although a growth-regulatory role of IGFs on human breast cancer cells has not yet been fully investigated. In the present study, we examined the receptor binding and the effect on growth of IGFs and insulin in a human breast cancer cell line (T-47D). Specific binding of 125I-basic somatomedin (...

Insulin-like growth factors I and II (IGF-I and -II) and their regulatory proteins are secreted by cells of the cardiovascular system. They are growth promoters for arterial cells and mediators of cardiovascular disease. IGFs are bound to IGF binding proteins (IGFBPs), which modulate IGF ligand-receptor interaction and consequently to IGF action. IGFBPs are in turn posttranslationally modulated...

PROLIFERATION OF hematopoietic cells is controlled by a coordinated hierarchy of growth factors and their inhibitors. These growth factors form complex signaling networks either by stimulating or inhibiting cell proliferation and differentiation. They govern all growth stages of blood cells that emerge from a small common pool of ancestral stem cells. In addition, biologic effects are altered b...

Insulin-like growth factor (1GFJ.s circulate in plasma as large mol wt proteins bound to specific proteins, termed IGF-binding proteins (IGFBPs). As IGFBPs have been shown to produce artifacts in IGF radioligand assays, various extraction procedures have been proposed to eliminate IGFBPs from biological samples before radioligand assays. Comparison of acid-ethanol and C,, Sep-Pak extraction met...

The role of somatomedin/insulin-like growth factors (Sm/IGFs) in neural growth and development is not clearly defined. To characterize Sm/IGF receptors and to correlate binding with the biologic actions of Sm/IGFs in a homogeneous population of neural cells, we isolated and studied a nearly pure population of cultured astroglial monolayers derived from cerebral cortices of neonatal rats. Bindin...

Insulin-like growth factors are single chain polypeptides. There are two principle IGFs referred to as IGF-I and IGF-II. IGF-1 is a polypeptide hormone with a molecular weight of 7.6-kDa structurally similar to insulin. In 1957, it is identified by Salmon and Daughaday. Because of the its ability to stimulate the sulfation of the cartilage proteoglycans, it was regarded as a sulphation factor [...