Glucose metabolism that is associated with abnormally high blood glucose can lead to high levels of glycation. Glycation is the non-enzymatic attachment of sugars to major molecules in the body, including proteins, lipids, and nucleic acids. Glycation reactions generate advanced glycation end-products (AGEs) and glycotoxin intermediates. AGEs cause abnormal and destructive functioning of body proteins, lipids, and nucleic acids. AGE-associated damage is suspected in the pathogenesis of many diseases and age-related deteriorations, such as atherosclerosis, Alzheimer's disease, and severe diabetic complications, including neuropathy, nephropathy, retinopathy, and cataracts. Gymnema sylvestre is an Ayurvedic botanical that may assist in the regeneration and repair of pancreatic beta cells. Gymnema is also suspected of reducing intestinal glucose absorption. Bitter melon(Momordica charantia) grows in tropical areas, including parts of East Africa, Asia, the Caribbean, and South America, where it is used as a food as well as a medicinal remedy. The fruit of this plant lives up to its name—it tastes very bitter. At least three different groups of constituents in bitter melon have been reported to have hypoglycemic (blood sugar lowering) or other actions of potential benefit in diabetes mellitus. These include a mixture of steroidal saponins known as charantin, insulin-like peptides, and alkaloids. Research shows that (-) hydroxycitric acid helps maintain a healthy balance of hepatic lipogenesis and gluconeogenesis, thus preventing excessive conversion of glucose from carbohydrate into body fat. It is found in Garcinia cambogia, a tropical fruit grown in Asian rain forest area. Research also indicates that (-) hydrocitric acid plays an important role in the regulation of a normal appetite. Alpha-lipoic acid is a fat- and water-soluble, sulfur- containing coenzyme. It functions in the body much like a B-vitamin, since it is involved in energy production. As part of several multi-enzyme complexes located in the mitochondria, alpha-lipoic acid is essential for metabolizing carbohydrates, proteins, and fats, and for the conversion of their energy into ATP. Two of these enzyme complexes, PDH (pyruvate dehydrogenase) and alpha-KGDH (alpha-ketoglutarate dehydrogenase) are part of the citric acid cycle (Krebs cycle), and as such assume a central role for general energy production. Another lipoic acid containing enzyme complex, BCKADH (branched-chain keto-acid dehydrogenase), is involved in deriving energy from the branched chain amino acids, leucine, isoleucine, and valine. A related metabolic function of alpha-lipoic acid is its role in blood glucose disposal. This important coenzyme appears to be necessary for the normal transport of blood glucose into the cell. This may be explained by its functions in the glucose-metabolizing enzymes, PDH and alpha-KGDH, but some researchers suspect a more direct role in cellular glucose uptake at the cell membrane. Chromium is anintegral component of the glucose tolerance factor(GTF), a naturally occurring compound of chromium, nicotinic acid, and amino acids that us essential for proper glucose metabolism. Adequate chromium nutrition is essential for the formation of GTF and subsequent control of blood glucose levels.