Role of Two Types of Glucose Transporters in Enlarged Adipocytes From Aged Obese Rats
Role of Two Types of Glucose Transporters in Enlarged Adipocytes From Aged Obese Rats
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两种葡萄糖转运蛋白在老年肥胖大鼠脂肪细胞增大中的作用
DOI：
10.2337/diab.39.12.1543
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发表时间：
1990
期刊：
影响因子：
7.7
通讯作者：
H. Itakura
中科院分区：
文献类型：
--
作者：
O. Ezaki;Naoko Fukuda;H. Itakura
研究了增大的老化脂肪细胞中胰岛素抵抗葡萄糖转运活性的机制。通过测量3-O-甲基葡萄糖转运和HepG 2红细胞/葡萄糖转运蛋白（GLUT 1）的浓度来评估葡萄糖转运活性，并通过免疫印迹法估计肌肉/脂肪组织转运蛋白（GLUT 4）。基础葡萄糖转运活性增加6.3倍/细胞，但由于细胞扩大，每单位细胞表面积保持不变。最大胰岛素刺激的转运活性保持不变，每个细胞，但每单位细胞表面积下降。在每个蛋白质的基础上，老年大鼠的GLUT 1和GLUT 4分别下降到年轻大鼠的60%和10%。然而，当每个馏分的蛋白质含量和标志酶的回收率用于估计完整脂肪细胞中转运蛋白的量时，每个细胞的GLUT 1的量保持相对恒定，而GLUT 4的量减少。在年轻大鼠的基底细胞中，每个细胞的总GLUT 1的31%位于质膜中，而在老年大鼠的基底细胞中，63%位于质膜中。因此，在比较来自老年大鼠的基底脂肪细胞与来自年轻大鼠的基底脂肪细胞时，质膜中每个细胞的GLUT 1增加了2.8倍，但这种增加小于运输活性的增加（6.3倍）。在年轻大鼠的基底细胞中，总GLUT 4的8%位于质膜中，并且在胰岛素治疗下观察到4.5倍的增加，但是老年大鼠的每个部分中的GLUT 4的量显著降低。这些发现表明，GLUT 4的急剧减少是胰岛素刺激的葡萄糖摄取减少的主要原因，并且位于质膜上的GLUT 1在维持基础葡萄糖转运活性中起作用。
The mechanism of insulin-resistant glucose-transport activity in enlarged aged adipocytes was examined. Glucose-transport activity was assessed by measuring 3-O-methylglucose transport and the concentration of HepG2 erythrocyte/glucose transporter (GLUT1), and the muscle/adipose tissue transporter (GLUT4) was estimated by immunoblotting. Basal glucose-transport activity increased 6.3-fold/cell but remained constant per unit cellular surface area due to cell enlargement. Maximal insulin-stimulated transport activity remained constant per cell but decreased per unit cellular surface area. On a per protein basis, GLUT1 and GLUT4 from aged rats decreased to ∼60 and 10% of those from young rats, respectively. However, when the protein content of each fraction and the recoveries of marker enzymes were used for estimating the amount of transporters in intact adipocytes, the amount of GLUT1 per cell remained relatively constant, whereas that of GLUT4 decreased. In basal cells from young rats, 31% of the total GLUT1 per cell was located in the plasma membrane, whereas in those from aged rats, 63% was located in the plasma membrane. Thus, in comparing basal adipocytes from aged rats with those from young rats, GLUT1 per cell in the plasma membrane increased 2.8-fold, but this increase was less than that of transport activity (6.3-fold). In basal cells from young rats, 8% of the total GLUT4 was located in the plasma membrane, and a 4.5-fold increase was observed with insulin treatment, but the amount of GLUT4 in each fraction from aged rats markedly decreased. These findings suggest that the dramatic decrease of GLUT4 is a major cause of decreased insulin-stimulated glucose uptake and that GLUT1 located in the plasma membrane plays a part in maintaining basal glucose-transport activity.
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大鼠脂肪细胞中葡萄糖转运蛋白、胰岛素受体和胰岛素的回收。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Ezaki,O;Kasuga,M;Akanuma,Y;Takata,K;Hirano,H;Fujita-Yamaguchi,Y;Kasahara,M
通讯作者：
Kasahara,M
脂肪细胞中胰岛素敏感的葡萄糖转运机制的能量依赖和蛋白质合成无关的再循环。
DOI：
--
发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kono,T;Suzuki,K;Dansey,LE;Robinson,FW;Blevins,TL
通讯作者：
Blevins,TL
脂肪细胞胰岛素抵抗：衰老、肥胖、运动和食物限制的影响。
DOI：
10.1152/jappl.1987.62.1.95
发表时间：
1987
期刊：
Journal of applied physiology (Bethesda, Md. : 1985)
影响因子：
--
作者：
Craig,BW;Garthwaite,SM;Holloszy,JO
通讯作者：
Holloszy,JO
DOI：
10.1073/pnas.86.8.2535
发表时间：
1989-04-01
影响因子：
11.1
作者：
CHARRON, MJ;BROSIUS, FC;LODISH, HF
通讯作者：
LODISH, HF
糖尿病和胰岛素治疗的糖尿病大鼠脂肪细胞中两种葡萄糖转运蛋白的差异调节。
DOI：
10.1172/jci114180
发表时间：
1989
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Kahn,BB;Charron,MJ;Lodish,HF;Cushman,SW;Flier,JS
通讯作者：
Flier,JS