Chronic exposure of β-cells to triacylglycerol or fatty acids either in vitro or in vivo decreases β-cell capacity to respond to an acute increase in glucose levels (57,58). This concept is far from new (59,60), but the observations of what happens during reversal of diabetes provide a new perspective. β-Cells avidly import fatty acids through the CD36 transporter (24,61) and respond to increased fatty acid supply by storing the excess as triacylglycerol (62). The cellular process of insulin secretion in response to an increase in glucose supply depends on ATP generation by glucose oxidation. However, in the context of an oversupply of fatty acids, such chronic nutrient surfeit prevents further increases in ATP production. Increased fatty acid availability inhibits both pyruvate cycling, which is normally increased during an acute increase in glucose availability, and pyruvate dehydrogenase activity, the major rate-limiting enzyme of glucose oxidation (63). Fatty acids have been shown to inhibit β-cell proliferation in vitro by induction of the cell cycle inhibitors p16 and p18, and this effect is magnified by increased glucose concentration (64). This antiproliferative effect is specifically prevented by small interfering RNA knockdown of the inhibitors. In the Zucker diabetic fatty rat, a genetic model of spontaneous type 2 diabetes, the onset of hyperglycemia is preceded by a rapid increase in pancreatic fat (58). It is particularly noteworthy that the onset of diabetes in this genetic model is completely preventable by restriction of food intake (65), illustrating the interaction between genetic susceptibility and environmental factors.
This medical-grade polyester is currently used in teeth guards that kids and adults wear at night, in tiny tubes used to guide the growth of damaged nerve fibers and in surgical sutures. Researchers are also looking at PCL’s potential as an implant to deliver medications directly to the eyes and to tumors and as a scaffold for growing human tissue. PCL may be an ideal package for islet cells, the studies note, because it can be used to create thin, flexible membranes with pores that let in glucose and nutrients, let out insulin and exclude bigger immune-system molecules.
Diabetes is a costly disease, placing a high financial burden on the patient and the healthcare system. If poorly managed or left untreated, it can cause blindness, loss of kidney function, and conditions that require the amputation of digits or limbs. The CDC reports that it’s also a major cause of heart disease and stroke and the seventh leading cause of death in the United States.
One easy way to increase your fat content and quit snacking is to begin your meal by eating an avocado. I and others I know have used this trick to easily quit snacking. Avocados protect you from one of the reasons some dietary research wrongly claims that high-fat diets are bad for you: the danger of gorging yourself on delicious, fatty foods. With plain avocados, there is little danger of gorging. Another danger is clogging your arteries and giving yourself heart disease. But it’s been amply shown that the blame for that falls squarely on trans fats, like margarine. If you see any product with the words “partially hydrogenated” or “hydrogenated” in the list of ingredients, put it back, it’s a trans fat. On the other hand, any fat that comes directly from an animal or plant is not a trans fat and can be safely consumed.