As the name indicates, IGF-12 has similar properties to insulin, and it has improved blood sugar levels in type 2 diabetes patients. High doses of growth hormone have been shown to increase insulin resistance, but IGF-1 administration actually normalized the insulin resistance in a group of healthy volunteers. They were looking at several different things, the effect of IGF-1 on protein metabolism, it’s ability to stop the protein wasting caused by glucocorticosteroid drugs like prednisone, and it’s effects on insulin and glucose metabolism. This same study found that if they gave 100 micrograms of IGF-1 per kg of body weight given twice daily enhanced the body’s protein metabolism in the same way as HGH did.
Like GH it markedly decreased the protein break down in the volunteers who were taking prednisone. But as growth hormone in an earlier study caused carbohydrate intolerance and insulin resistance when given in combination with prednisone. IGF-1 did not cause these diabetes like effects. Instead those subjects who received IGF-1 along with prednisone had normal glucose metabolism. This was remarkable , say the researchers, in light of the fact that glucocorticoids are know to suppress circulating insulin and decrease insulin sensitivity. As a result of this and previous studies, the researchers believe that IGF-1 offers promise in the treatment of catabolic states, such as patients who require IV feeding after surgery.