Intestinal glucose absorption comprises two components. One is classical active absorption mediated by the Na+/glucose cotransporter. The other is a diffusive component, formerly attributed to paracellular flow. Recent evidence, however, indicates that the diffusive component is mediated by the transient insertion of glucose transporter type 2 (GLUT2) into the apical membrane. This apical GLUT2 pathway of intestinal sugar absorption is present in species from insect to human, providing a major route at high sugar concentrations. The pathway is regulated by rapid trafficking of GLUT2 to the apical membrane induced by glucose during assimilation of a meal. Apical GLUT2 is therefore a target for multiple short-term and long-term nutrient-sensing mechanisms. These include regulation by a newly recognized pathway of calcium absorption through the nonclassical neuroendocrine l-type channel Cav1.3 operating during digestion, activation of intestinal sweet taste receptors by natural sugars and artificial sweeteners, paracrine and endocrine hormones, especially insulin and GLP-2, and stress. Permanent apical GLUT2, resulting in increased sugar absorption, is a characteristic of experimental diabetes and of insulin-resistant states induced by fructose and fat. The nutritional consequences of apical and basolateral GLUT2 regulation are discussed in the context of Western diet, processed foods containing artificial sweeteners, obesity, and diabetes.

中文翻译：

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肠道中的糖吸收：GLUT2的作用。

肠道葡萄糖吸收包括两个成分。一种是由Na + /葡萄糖共转运蛋白介导的经典活性吸收。另一个是扩散成分，以前归因于细胞旁血流。然而，最近的证据表明，扩散成分是由2型葡萄糖转运蛋白（GLUT2）瞬时插入根尖膜介导的。从昆虫到人类的物种中都存在这种肠道糖吸收的根尖GLUT2途径，这是高糖浓度下的主要途径。在膳食同化过程中，葡萄糖可将GLUT2快速转运至顶端膜，从而调节该途径。因此，顶端GLUT2是多种短期和长期营养传感机制的目标。这些包括通过在消化过程中运行的非经典神经内分泌l型通道Cav1.3的新认识的钙吸收途径进行调节，天然糖和人造甜味剂，旁分泌和内分泌激素（尤其是胰岛素和GLP-2）激活肠道甜味受体。和压力。永久性根尖GLUT2导致糖吸收增加，是实验性糖尿病以及果糖和脂肪诱发的胰岛素抵抗状态的特征。在西方饮食，含有人造甜味剂的加工食品，肥胖症和糖尿病的背景下，讨论了根尖和基底外侧GLUT2调控的营养后果。旁分泌和内分泌激素，尤其是胰岛素和GLP-2，以及压力。永久性根尖GLUT2导致糖吸收增加，是实验性糖尿病以及果糖和脂肪诱发的胰岛素抵抗状态的特征。在西方饮食，含有人造甜味剂的加工食品，肥胖症和糖尿病的背景下，讨论了根尖和基底外侧GLUT2调控的营养后果。旁分泌和内分泌激素，尤其是胰岛素和GLP-2，以及压力。永久性根尖GLUT2导致糖吸收增加，是实验性糖尿病以及果糖和脂肪诱发的胰岛素抵抗状态的特征。在西方饮食，含有人造甜味剂的加工食品，肥胖症和糖尿病的背景下，讨论了根尖和基底外侧GLUT2调控的营养后果。