Expression of SGK isoforms in human proximal tubular epithelial cells under the condition of high glucose concentration
- VernacularTitle:糖皮质激素诱导的蛋白激酶3种亚型在高糖诱导的人肾小管上皮细胞中的表达
- Author:
Xiaoli ZHANG
;
Quansheng WANG
;
Yumei WANG
;
Zhonghua ZHU
;
Anguo DENG
;
Yuxi FENG
- Publication Type:Journal Article
- Keywords:
Glucocorticoids;
Protein kinases;
High glucose;
Kidney tubules, proximal;
Fibronectins
- From:
Chinese Journal of Pathophysiology
1986;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To investigate the effect of high glucose concentration on serum and glucocorticoid induced protein kinase (SGK) mRNA and protein expressions in human proximal tubular epithelial cells (HKC) and the possible role of SGK in the production of extracellular matrix (ECM) of HKC under the condition of high glucose. METHODS: HKC was divided into 3 groups: control glucose group (CG group, 5 5 mmol/L D-glucose); high glucose group (HG group, 25 mmol/L D-glucose) and osmotic control group (MG group, 19 5 mmol/L mannitol and 5 5 mmol/L D-glucose). The expressions of SGK mRNA and protein were assessed by semi-quantitative RT-PCR and Western blotting respectively. The level of secretary and cytoplasmic fibronectin (FN) were detected by enzyme-linked immunoabsordent assay (ELISA) and indirect-immunofluorescence. RESULTS: HKC expressed SGK1, SGK2 and SGK3 at mRNA and protein levels. Their mRNA level were up-regulated since 2 hours after cells exposed to D-glucose and this up-regulation persisted to the end of 8th hour, and SGK1 protein level elevated simultaneously. On the other hand, the increased FN secretion by high glucose was in a time-dependent manner and its improved secretion threshold was just followed by the high expression of SGK1. CONCLUSIONS: In response to high glucose, the expression of SGK1, SGK2 and SGK3 in human proximal tubular epithelial cells were up-regulated which was accompanied with FN accumulation. The high expression of SGK may mediate overproduction of ECM in proximal tubular epithelial cells and contribute to the diabetic nephropathy.
