Insights into modulation of (and by) growth hormone signaling

Abstract

rowth hormone is a 22-kd polypeptide hormone present in most vertebrates and is derived largely from the anterior pituitary gland. GH is an important regulator of somatic growth and metabolism in human beings. A deficiency in GH results in short stature (if it occurs in childhood) and alterations in body morphology and fat and carbohydrate metabolism. Excessive GH production leads to the syndrome of acromegaly (including bony and cartilageneous overgrowth, organomegaly, glucose intolerance, and—if arising before puberty—gigantism). The past two decades have witnessed a dramatic increase in our understanding of the cellular and molecular basis of GH action. Much of this information is detailed in recent comprehensive and exhaustively referenced review articles.1,2 The current review primarily addresses particular ways in which cellular GH signaling can be modulated and how GH signaling may affect other important signaling pathways. In addressing these issues, we will summarize recent data, largely from the laboratories of the communicating author and collaborators, which are selectively referenced.