The growth hormone/insulin-like growth factor-1 axis in health and disease

Published on December 1, 2007 Reviewed on December 4, 2019   31 min

Other Talks in the Therapeutic Area: Cardiovascular & Metabolic

0:00
So I'm Derek LeRoith, Chief of the Division of Endocrinology, Diabetes, and Bone Diseases at Mount Sinai School of Medicine. And today, my discussion is going to be on "The Growth Hormone and Insulin-Like Growth Factor-1 Axis in Health and Disease".
0:17
So in discussing growth hormone IGF-I axis, today what we want to cover is the normal physiology of the axis, disorders of the growth hormone IGF axis, including disorders like acromegaly, growth retardation and aging. And then finally, we'll discuss growth hormone and IGF-I axis in conditions such as diabetes, tumor hypoglycemia and in general, forms of cancer.
0:46
So let's talk firstly about the normal physiology of the growth hormone IGF-I axis.
0:53
This slide shows the hypothalamus and the pituitary. And as you can see, there are hypothalamic-releasing and hypothalamic inhibitory hormones, which reach the pituitary gland and stimulate the release of prolactin, growth hormone, thyrotropin or TSH, luteinizing hormone, follicular-stimulating hormone, and corticotropin. And there are specific cells as shown here, the lactotroph, the mammosomatotroph, the thyrotroph, the gonadotroph, and the corticotroph, each of which release these hormones. But the hormone that we'll be dealing with today is growth hormone.
1:34
So this slide shows how the growth hormone, IGF axis works under normal physiological conditions. As you can see, stress, sleep, exercise, etc affect the hypothalamus to release the growth hormone-releasing hormone, which reaches the anterior pituitary to stimulate growth hormone released to the periphery. Once it reaches the liver, muscle, adipose, or bone, it then stimulates the synthesis and release of insulin-like growth factor-1, or IGF-I, which then reaches the circulation, and has a positive effect on target tissues. IGF-I, on the other hand, has a negative feedback to the hypothalamus and the pituitary, to inhibit growth hormone. And this is the normal negative feedback regulation so well-known in the endocrine system.
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The growth hormone/insulin-like growth factor-1 axis in health and disease

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