On the nature of the sugar in blood

Revisiting "Vegetables" to combat modern epidemic of imbalanced glucose homeostasis

Vegetables have been part of human food since prehistoric times and are considered nutritionally necessary and good for health. Vegetables are rich natural resource of biological antioxidants and possess capabilities of maintaining glucose homeostasis. When taken before starch-rich diet, juice also of vegetables such as ridge gourd, bottle gourd, ash gourd, chayote and juice of leaves of vegetables such as radish, Indian Dill, ajwain, tropical green amaranth, and bladder dock are reported to arrest significantly the rise in postprandial blood glucose level. Juice of vegetables such as ash gourd, squash gourd, and tropical green amaranth leaves are observed to tone-down sweet-beverages such as sucrose, fructose, and glucose-induced postprandial glycemic excursion. On the other hand, juice of egg-plant and juice of leaves of Ceylon spinach, Joyweed, and palak are reported to augment starch-induced postprandial glycemic excursion; and juice of leaves of Ceylon spinach, Joyweed, and radish supplement to the glucose-induced postprandial glycemia. Vegetables possess multifaceted antihyperglycemic activities such as inhibition of pancreatic α-amylase and intestinal α-glucosidase, inhibition of protein-tyrosine phosphatase 1β in liver and skeletal muscles, and insulin mimetic and secretagogue activities. Furthermore, they are also reported to influence polyol pathway in favor of reducing development of oxidative stress, and consequently the development of diabetic complications. In the wake of emergence of modern maladaptive diet-induced hyperglycemic epidemic therefore, vegetables may offer cost-effective dietary regimen to control diet-induced glycemic over load and future development of diabetes mellitus. However, for vegetables have been reported to do both, mitigate as well as supplement to the diet-induced postprandial glycemic load, care is required in selection of vegetables when considered as medicament.

The action of glucosone on normal animals (mice) and its possible significance in metabolism

The almost simultaneous discovery by Emil Fischer (1) in Berlin and by Irvine, Fyfe and Hogg (2) at St. Andrews of the existence of reactive forms of sugars, coupled with the observations of Hewitt and Pryde (3) on the optical changes undergone by a sugar solution when introduced into a loop of living intestine, initiated the speculations of Winter and Smith (4, 5, 6) on the part played by the so-called “γ-glucose” in carbohydrate metabolism. The latter workers found that the optical activity and the copper-reducing power of a protein-free filtrate from normal blood were not compatible with the idea that the sugar present existed entirely as the ordinary equilibrium mixture of αβ-glucose. Having also observed that the fresh filtrate reduced potassium permanganate solution in the cold, they concluded that the glucose of normal blood exists in the unstable γ-form. Further, as the examination of the blood of diabetics pointed to their blood sugar being present as αβ-glucose, they suggested that the conversion of the relatively stable αβ-variety into the reactive γ-form was an essential step for utilisation of the sugar by the body cells and that this conversion was brought about by the action of insulin. These speculations unfortunately have not stood the test of later experiments (7, 8, 9), and though in 1923 Irvine (10), in the course of a review of the chemical evidence for the existence of a γ-form of glucose, pointed out the possibility that such a form may be produced in the body as an intermediary product during the glucose metabolism, he, in collaboration with Herring and Macleod (11), soon afterwards furnished experimental evidence against the theory of Winter and Smith, by showing that glucose monoacetone, a readily hydrolysable derivative of γ-glucose, is without action when administered in cases of insulin hypoglycæmia. More recently, however, the same idea, or one very similar, has been revived by Lundsgaard and Holboll (12, 13). They claim that when insulin and muscle tissue are added to a solution of ordinary a αβ-glucose, with a specific rotation of +52·5°, and the mixture incubated at 37°C., no change in reducing power takes place, but the optical rotatory value decreases to a new value varying from +15·9° to +42·2°, because of the formation of what they call “new” or “neo-glucose.” Insulin alone, or muscle tissue alone, does not produce the change, but the two factors, insulin and the active substance or principle in fresh finely minced muscle tissue, must act simultaneously (14).