Originally Posted by Deep_Fried
Interesting post and info - however the fact is glucophages' exact mechanism of action isnt 100% known. In fact more recent evidence suggests that it exudes its effects significantly at the insulin receptor site (tyrosene phosphatase). Its also believed to stimulate glycolysis (glucose removal from blood) ....and decrease glucose absorption rate in the gi tract. In fact even the AMPK theory outlined above is in question - it is now believed that AMPK may INCREASE insulin action - not decrease its production.. See Below:
Potential role of the AMP-activated protein kinase in regulation of insulin action
Jonathan S. Fisher
Department of Biology, 3507 Laclede Ave., Saint Louis University, St. Louis, MO 63103, USA
Received 12th December 2005 © Cellscience 2006
Because of the predominant role of skeletal muscle in insulin-stimulated clearance of blood glucose, understanding mechanisms for increasing the ability of muscle to respond to insulin could potentially lead to novel strategies for treatment or prevention of diabetes. Recently, the AMP-activated protein kinase (AMPK), a heterotrimeric serine/threonine kinase, has emerged as a promising candidate for the potentiation of insulin action. Several antidiabetic drugs have been shown to activate AMPK, cellular stresses such as exercise that increase AMPK activity also increase insulin action, and several downstream targets of AMPK seem to be involved in regulation of insulin action. Although the picture is currently incomplete, it seems possible that AMPK or one of its effectors is a positive regulator of insulin-stimulated glucose transport. In addition to a discussion of the latest literature regarding AMPK and insulin action, this review includes a non-technical summary for students, academics from other fields, interested professionals, and the general public.
Non-technical summary
Insulin, a natural hormone which is secreted into the bloodstream after the consumption of carbohydrate rich meals, causes some tissues, including skeletal muscle (the muscles that make the body move), fat, and heart, to increase their uptake of glucose (blood sugar). Of these tissues, skeletal muscle is by far the most massive, comprising approximately 40% of body weight. The majority of glucose cleared from the bloodstream in response to insulin is stored in muscle. Therefore, muscle is of primary importance in the insulin-related control of blood glucose levels. Muscle that does not react properly to insulin often underlies the increased blood glucose concentrations which are the hallmark of diabetes.
It has been known for over two decades that a short time after exercise insulin works much better at stimulating glucose transport into muscle. Recently, evidence has emerged that a protein called the "AMP-activated protein kinase" (AMPK) could be responsible for increasing the sensitivity of muscle to insulin. AMPK appears to be a cellular fuel gauge that senses metabolic stresses or nutritional deficiency and subsequently controls several cellular processes to muster fuel resources and conserve energy. For example, it appears that AMPK can increase glucose transport into muscle but also increase the rate of fat burning by muscle. AMPK appears to activate several signaling pathways in muscle that are also stimulated by insulin, so it is possible that AMPK and insulin together could have synergistic effects on the signaling events that lead to glucose transport. AMPK also seems to prevent the negative effects on insulin's action of another cellular fuel gauge that senses nutrient sufficiency. Finally, it seems possible that the positive effect of AMPK on insulin's ability to stimulate glucose transport may simply be a result of increased fat burning that clears fat molecules (that inhibit insulin action), out of muscle cells.
Exercise robustly potentiates the action of insulin. However, some people at risk of developing diabetes are unable to exercise. Understanding the cellular mechanisms for increased sugar uptake into muscle is an important first step in developing drug strategies for treating or preventing diabetes when exercise is not a viable option.
So i wouldnt say for certain glucophage is catabolic. I certainly also wouldnt say its anabolic.I think Nark summed it up perfectly : its an aid - great while bulking or cutting.
I agree ......
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