The Role of Adipose Tissue-Derived Stem Cells in Ischemic Acute Renal Injury in Rats / 대한신장학회지

ABSTRACT

PURPOSE: The aim of this study is to explore the role of human adipose tissue-derived adult stem cells (ASCs) in repair of acute ischemic renal injury. METHODS: Acute ischemic tubular necrosis was induced in Spraque-Dawley rats (n=15) by clamping bilateral renal pedicles for 40 minutes. Before releasing the clamps, iron labeled stem cells (1x106/0.3 mL) were directly injected to one side of renal cortex and phosphate-buffered saline (PBS) injections were done as a control to the opposite kidney. The examination on both kidney was done after 1, 2 and 4 weeks (n=5 each). The evaluation of the degree of tubular necrosis and the location of stem cells was done by light and electron microscopically. RESULTS: The rats were all alive without rejection. Morphologically, recovery rate was increased up to about 20% in ASCs injection group in 2 weeks-group (p<0.001). Few Prussian-blue positive cells were demonstrated in 2 weeks-group and more cells were present in 4 weeks-group. The cells which were positively stained in Prussian-blue stain were mainly located in peritubular spaces. Electron microscopically, fine iron granules with electron density were found in the cytoplasm of peritubular endothelial cells. CONCLUSION: As a result, the endothelial cells might be differentiated from injected ASCs. It seems that stem cells help repairing the tubular epithelium in acute renal failure model, not by tubulogenesis but by vasculogenesis. This outcome suggests that the possibility of therapeutic use of ASCs without immunosuppression of recipients in acute ischemic renal injury.