Regulation of insulin-like growth factor-I ...

Posted on 2003-04-26 14:06:22 in (HGH) Clinical Research Abstracts |

Regulation of insulin-like growth factor-I in skeletal muscle and muscle cells.

Growth hormone (GH) and insulin-like growth factor-I (IGF-I) are potent regulators of muscle mass. Transgenic mice that over-express these proteins exhibit dramatically enlarged skeletal muscles. In contrast, malnutrition, critical illness, sepsis, and aging are all associated with a dramatic reduction in muscle mass and function. The circulating concentration of IGF-I and the expression of IGF-I in skeletal muscle are also reduced during catabolic states. Consequently, GH has been used clinically to increase lean body mass in patients with muscle wasting. Likewise, delivery of IGF-I specifically into muscle has been proposed as a genetic therapy for muscle disorders. A better understanding of the regulation of IGF-I expression in skeletal muscle and muscle cells is therefore of importance. Yet, our knowledge in this area has been limited by a lack of GH responsive muscle cells. In addition the IGF-I gene spans over 90 kb of genomic DNA and it exhibits a very complex regulatory pattern. This review will summarize our knowledge of the control of muscle mass by GH, IGF-I, anabolic steroids, exercise and other growth enhancing hormones. We will also highlight recent advances in the regulation of IGF-I and signal transducers and activators of transcription (Stats) by GH. A special emphasis will be placed on the interaction of IGF-I and proinflammatory cytokines in skeletal muscle and muscle cells.


Frost RA, Lang CH.
Minerva Endocrinol 2003 Mar;28(1):53-73
Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University Hershey, PA, USA.
PMID: 12621363 [PubMed - in process]

 

Health Headlines MORE »

For every 10 g per day increase in soluble fiber intake, a woman may reduce her risk of breast cancer by up to 26%.
Peptides from soybeans modulate neurotransmitters, thereby helping to boost circulation in the brain.
Capsaicin (found in hot peppers) and capsiates (present in sweet peppers) exert modest weight management benefits.
While over 20% of U.S. adults receive periodic health examinations each year, many do not receive recommended preventive screening tests and counseling services
Researchers from Norway suggest a mechanism by which stress may make a person fat, and being obese may create stress.
Swedish researchers report that people who are short on sleep experience greater levels of hunger.
Among women with Generalized Anxiety Disorder (GAD), regular physical activity helps to reduce anxiety, irritability, feelings of tension, low energy and pain.
For every 100 mg per-day increase in magnesium in the diet, stroke risk may decline by up to 9%.
The best male marathon runners over age 65, and the best female marathon runners over age 45, continue to consistently improve their performance.
UCLA-led team safely uses human embryonic stem cells to treat macular degeneration.
ANTI-AGING TIP OF THE DAY
In Working Order
Men and women who stay mentally engaged in their original occupational field fare after retirement fare best mentally. University of Maryland (Maryland, USA) researchers studied 12,189 retired men and women, ages 51 to 61 years at the beginning of the study. The team revealed that those retirees who continued to work in a bridge job experienced fewer major diseases...