Araújo João R, Gonçalves Pedro, Martel Fátima
Department of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
J Biochem. 2008 Aug;144(2):177-86. doi: 10.1093/jb/mvn054. Epub 2008 Apr 19.
The aim of this work was to investigate the putative modulation of glucose uptake in trophoblast cells by several dietary compounds and by drugs of abuse. For this, the acute (26 min) and chronic (48 h) effect of these substances on the apical uptake of 3H-2-deoxy-D-glucose (3H-DG) by a human choriocarcinoma cell line (BeWo) was determined. 3H-DG apical uptake by BeWo cells was time dependent, displayed saturable kinetics (Vmax=1210+/-29 nmol mg protein(-1) 6 min(-1) and Km=13.4+/-0.5 mM) and was insulin-insensitive and cytochalasin B-sensitive (by up to 60%). Acutely, acetaldehyde (30-100 mM), resveratrol, xanthohumol, epigallocatechin-3-gallate (100 microM), chrysin and quercetin (10-100 microM) decreased 3H-DG apical uptake, whereas rutin, catechin (10-100 microM), epicatechin (100 microM) and ethanol (10 mM) increased it. Quercetin and xanthohumol seem to be non-competitive inhibitors of 3H-DG apical uptake, whereas both epigallocatechin-3-gallate and acetaldehyde decreased both the Km and Vmax values. Chronically, rutin and myricetin increased the apical uptake of 3H-DG both isolated (0.1-1 microM) and in combination (both at 1 microM), whereas theophylline (0.1-1 microM) and amphetamine, 3,4-methylenedioxymethamphetamine (0.25-1 microM) and Delta9-tetrahydrocannabinol (1 nM) decreased it. In conclusion, 3H-DG apical uptake by BeWo cells is differentially modulated by different compounds present in drinks and by drugs of abuse.
本研究旨在探讨几种膳食化合物和滥用药物对滋养层细胞葡萄糖摄取的假定调节作用。为此,测定了这些物质对人绒毛膜癌细胞系(BeWo)顶端摄取3H-2-脱氧-D-葡萄糖(3H-DG)的急性(26分钟)和慢性(48小时)影响。BeWo细胞顶端摄取3H-DG具有时间依赖性,呈现饱和动力学(Vmax=1210±29 nmol mg蛋白-1 6分钟-1,Km=13.4±0.5 mM),且对胰岛素不敏感,对细胞松弛素B敏感(高达60%)。急性情况下,乙醛(30-100 mM)、白藜芦醇、黄腐酚、表没食子儿茶素-3-没食子酸酯(100 microM)、白杨素和槲皮素(10-100 microM)降低了3H-DG顶端摄取,而芦丁、儿茶素(10-100 microM)、表儿茶素(100 microM)和乙醇(10 mM)则增加了摄取。槲皮素和黄腐酚似乎是非竞争性3H-DG顶端摄取抑制剂,而表没食子儿茶素-3-没食子酸酯和乙醛均降低了Km和Vmax值。长期来看,芦丁和杨梅素单独(0.1-1 microM)及联合使用(均为1 microM)均增加了3H-DG顶端摄取,而茶碱(0.1-1 microM)、苯丙胺、3,4-亚甲基二氧甲基苯丙胺(0.25-1 microM)和Δ9-四氢大麻酚(1 nM)则降低了摄取。总之,BeWo细胞顶端摄取3H-DG受到饮料中不同化合物和滥用药物的差异调节。