基质硬度对人肾小管上皮细胞形态和葡萄糖转运蛋白表达的影响

Matrix stiffness impacts the morphology and the levels of glucose transporter proteins in human renal tubular epithelial cells

肾小管间质纤维化以细胞外基质沉积、瘢痕硬化为特点,是慢性肾脏疾病发展至终末期肾衰竭的共通途径。本研究拟构建体外细胞培养模型探索基质硬度对肾小管上皮细胞形态和功能的影响。采用光催化成胶的聚丙烯酰胺凝胶(PAAgel)制备模拟肾间质纤维化组织硬度的凝胶基质(1~40kPa);接种人肾小管上皮细胞(HK-2)于不同硬度的PAA gel表面,采用免疫荧光染色和共聚焦显微镜考察基质硬度对HK-2形态的影响,并对HK-2细胞上的葡萄糖转运蛋白1 (GLUT1)、葡萄糖转运蛋白2 (GLUT2)和葡萄糖转运蛋白5 (GLUT5)的分布进行定性和半定量考察。研究发现,随着基质硬度增加, HK-2细胞上的GLUT1表达量显著降低, GLUT5在细胞整体的表达量显著下降,而GLUT2的表达和分布未见明显改变。

As the common pathway of chronic renal diseases leading to end-stage renal failure, renal tubulointerstitial fibrosis is characterized by the deposition of extracellular matrix and scar hardening. Our study aimed to construct an in vitro cell culture platform to explore the impact of matrix stiffness on cell morphology and function of renal tubular epithelial cells. Photopolymerized polyacrylamide gels（PAA gel） with varying stiffnesses as model substrates was selected to simulate the matrix stiffness of normal and fibrotic renal tissues with elastic moduli ranging from 1 to 40 kPa. The human renal tubular epithelial cells（HK-2） were seeded on the surface of PAA gels. The impact of matrix stiffness on the morphology of HK-2 were investigated via immunofluorescence staining and confocal microscopy. The expression levels of glucose transporter 1（GLUT1）, glucose transporter 2（GLUT2）, glucose transporter 5（GLUT5） were semi-quantitatively analyzed. With increasing matrix stiffness, both the levels of GLUT1 and GLUT5 in HK-2 cells were significantly decreased, whereas the expression level and the distribution pattern of GLUT2 in HK-2 remained unchanged with stiffness variation.