Glucose uptake enhancer

A conclusion reached by Eigenbrodt et al. (1985) is that the metabolic behavior of tnmor (or cancer) cells differs from normal cells in that the forma show increased anaerobic glycolysis and glucose uptake, enhanced glutaminolysis enhanced nucleic acid (DNA) synthesis capacity, and enhanced lipid synthesis (p. 143). 

Glucose uptake T Myocyte enhancer factor-2 f GLUT4 expression Muscle... 

Antidiabetic Drugs other than Insulin. Figure 3 The antihyperglycaemic effect of metformin involves enhanced insulin-mediated suppression of hepatic glucose production and muscle glucose uptake. Metformin also exerts non-insulin-dependent effects on these tissues, including reduced fatty acid oxidation and increased anaerobic glucose metabolism by the intestine. FA, fatty acid f, increase i decrease. 

Thiazolidinediones are known to increase insulin sensitivity by stimulating peroxisome proliferator-activated receptor gamma (PPAR-y). Stimulation of PPAR-y results in a number of intracellular and extracellular changes, including an increased number of insulin receptors, increased insulin receptor sensitivity, decreased plasma fatty acid levels, and an increase in a host of intracellular signaling proteins that enhance glucose uptake. 

C5a and C5a des Arg stimulate aerobic glycolysis, hexose monophosphate shunt activity, glucose uptake and the respiratory burst of human neutrophils. All of these processes are stimulated in neutrophil suspensions incubated in the absence of cytochalasin B, but the responses are considerably enhanced if this inhibitor of microtubule assembly is present. Stimulated rates of oxidative metabolism are maximal within 2 min of addition of peptides, with half-maximal responses obtained at 30-60 nM C5a and 1-3 pM C5a des Arg. 

Figure 16.3 Effects of insulin on the glucose/fatty acid cycle. Insulin enhances glucose metabolism by stimulating glucose uptake by muscle and adipose tissue and by inhibiting lipolysis in adipose tissue (see Chapter 12 for the mechanism of these effects). The effect of glucose metabolism on lipolysis is via stimulation of fatty acid esterification via glycerol 3-phosphate.

Tousch D, Lajoix AD, Hosy E, Azay-Milhau J, Ferrare K, Jahannault C, Cros G Petit P. (2008) Chicoric acid, a new compound able to enhance insulin release and glucose uptake. Biochem Biophys Res Commun 377 131-135. 

There are limitations in the use of FDG for viability assessment. Normal myocardium (normal perfusion and normal metabolism) in diabetics may not take up FDG due to insulin resistance associated with elevated free fatty acids in blood. Consequently, there is no FDG uptake anywhere in the heart and the study is uninterpretable. Flowever, giving insulin intravenously at the time of glucose loading enhances myocardial uptake, reduces free fatty acids in blood, and provides diagnostic images. 

Vanden Bossche and de Nollin and others [12-14] have shown that benzimidazole carbamates, such as mebendazole, inhibit glucose uptake by helminths in vivo and in vitro-, this enhances endogenous glycogen utilization and is accompanied by reduction in glycogenesis. 

It has been known for decades that tumors display enhanced rates of glucose uptake and glycolysis. We now know that these enhanced rates of glucose processing are not fundamental to the development of cancer, but we can ask what selective advantage they might confer on cancer cells. 

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