Permanent hexose transport upregulation in a respiration-deficient human fibroblast cell strain

Author:

Andrejchyshyn S.1,Continelli L.1,Germinario R. J.1

Affiliation:

1. Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec, Canada.

Abstract

The regulation of hexose transport was studied in a human diploid fibroblast respiration-deficient cell strain (WG750). Transport of 2-deoxy-D-glucose (2-DG) was greater than sixfold higher compared with an in vivo age-matched normal cell strain (MCH55). In addition, 3-O-methylglucose transport and 14CO2 production were elevated in the mutant cell strain. Kinetic analysis revealed that the increased sugar transport in mutant cells was due to an average 5.7-fold increase in the 2-DG maximal transport rate, with no observed differences in the transport Michaelis constant for both normal and mutant cells. Also, the inhibitor constants for D-glucose inhibition of 2-DG transport were nearly identical for both cell types. Glucose deprivation led to a similar time-dependent increase in hexose transport in both cell strains. Serum refeeding of glucose-fed serum-deprived cultures led to a progressive increase in 2-DG transport in normal cells, whereas mutant cells displayed a time-delayed increase in 2-DG transport. Exposure to 67 and 670 nM insulin stimulated 2-DG transport on average 1.99 +/- 0.25- and 2.33 +/- 0.26-fold, respectively, over basal transport in the normal cells, whereas the mutant cells were significantly less sensitive to the stimulatory effects of the hormone. Insulin binding and amino acid transport (i.e., alpha-aminoisobutyric acid uptake) in the normal and mutant cells were not different. Data obtained using Western blot analysis showed that WG750 (mutant) cells expressed an increase (approximately 4-fold) in total cellular HepG2 (erythroid-brain) transporter protein compared with normal cells, thus reflecting the changes seen in hexose transport.(ABSTRACT TRUNCATED AT 250 WORDS)

Publisher

American Physiological Society

Subject

Cell Biology,Physiology

Cited by 14 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3