Gene expression analysis of human mortal renal tubular epithelial cells chronically exposed to elevated levels of glucose

This study was designed to simulate the effect of hyperglycemia on the proximal tubule. This portion of the kidney is responsible for reabsorption of the filtered glucose, and thus, the amount reabsorbed is not regulated by insulin. A long-term exposure was designed to model aspects of renal demise seen in diabetes. We utilized mortal cultures of human renal tubule epithelial cells isolated from renal cortical tissue. Since the majority of these cells express the cell surface marker CD133, these cells can be used as a model for the progenitor cells that repopulate the nephron after a toxic insult. The outcome of the current study is that the lysosomal genes and mTOR were repressed. Four concentrations of glucose were used: 5.5 mM, representing the normal level, and 7.5, 11, and 16 mM, representing hyperglycemic glucose levels. Cells were cultured in these concentrations in triplicate. The cells were continually cultured and passaged three times before total RNA was purified for global gene expression analysis. Total exposure time was four weeks