Trioses and related substances: tools for the study of pancreatic beta-cell function.
Trioses, such as D-glyceraldehyde, have been used extensively for the study of stimulus-secretion coupling mechanisms in pancreatic beta-cells. It is generally assumed that trioses enter the glycolytic pathway at the triose phosphate level, and stimulate insulin release in a manner analogous to glucose. This review focuses on a number of triose effects that are not entirely consistent with this model. These effects are likely to result, at least in part, from the actions of alpha-ketoaldehydes. One such compound, methylglyoxal, appears to be a major contaminant of triose preparations, and exerts effects on the beta-cell identical to some of those evoked by glyceraldehyde. A related substance, hydroxypyruvaldehyde, is a product of triose autoxidation, which could exert similar effects. Study of the actions of trioses and alpha-ketoaldehydes could assist our understanding of cellular physiology, in general, and beta-cell function, in particular. These substances are also likely to be of pathophysiological importance, especially in the context of sugar toxicity and autoxidative cell damage.
Best
L
L
Department of Medicine, University of Manchester, England, UK. lbest@fs1.scg.man.ac.uk
Thornalley
P J
PJ
D000818:Animals; D002478:Cells, Cultured; D005985:Glyceraldehyde / Q000494:pharmacology; D006019:Glycolysis; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism; D007791:Lactoylglutathione Lyase / Q000378:metabolism; D010084:Oxidation-Reduction; D011765:Pyruvaldehyde / Q000378:metabolism / Q000494:pharmacology; D014306:Trioses / Q000494:pharmacology*
D007328:Insulin; D014306:Trioses; D005985:Glyceraldehyde; D011765:Pyruvaldehyde; D007791:Lactoylglutathione Lyase