Malaisse W J, Kadiata M M
Laboratory of Experimental Medicine, Brussels Free University, Brussels, Belgium.
Int J Mol Med. 1998 Sep;2(3):331-2. doi: 10.3892/ijmm.2.3.331.
Several monosaccharide polyacetate esters display higher biological efficiency than the corresponding unesterified carbohydrates, this being attributable to their capacity to cross the plasma membrane without requiring the intervention of a specific carrier system and to their subsequent intracellular esterase-catalyzed hydrolysis. Some of these esters, however, also exert a direct effect upon a receptor system apparently displaying analogies with that involved in the identification of bitter compounds by taste buds. For instance, under suitable experimental conditions, esters of non-nutrient monosaccharides, such as L-glucose, D-mannoheptulose or 2-deoxy-D-glucose, unexpectedly stimulate insulin release. The present work reveals that alpha-D-galactose pentaacetate and, to a lesser extent, beta-D-galactose pentaacetate both inhibit leucine-induced insulin release in rat pancreatic islets. This indicates that the postulated receptor system displays anomeric specificity and may participate in a negative modulation of insulin secretion. It is proposed that advantage could be taken of the negative insulinotropic action of D-galactose pentaacetate esters to prevent excessive insulin release in pathological situations.
几种单糖多乙酸酯比相应的未酯化碳水化合物表现出更高的生物学效率，这归因于它们能够在不需要特定载体系统干预的情况下穿过质膜，以及随后细胞内酯酶催化的水解作用。然而，其中一些酯类也对一种受体系统产生直接作用，该受体系统显然与味蕾识别苦味化合物所涉及的受体系统有相似之处。例如，在合适的实验条件下，非营养性单糖的酯类，如L-葡萄糖、D-甘露庚酮糖或2-脱氧-D-葡萄糖，出人意料地刺激胰岛素释放。目前的研究表明，α-D-半乳糖五乙酸酯以及在较小程度上的β-D-半乳糖五乙酸酯都能抑制大鼠胰岛中亮氨酸诱导的胰岛素释放。这表明假定的受体系统具有异头物特异性，可能参与胰岛素分泌的负调节。有人提出，可以利用D-半乳糖五乙酸酯的负促胰岛素作用来防止病理情况下胰岛素的过度释放。
