Bone marrow mesenchymal stem cell transplantation for treating irradiation-induced injury to the rat kidney / 中国组织工程研究

ABSTRACT

BACKGROUND:Bone marrow mesenchymal stem cells (BMSCs) can differentiate into renal paranchymal cells including renal intercapillary cells.BMSCs can repair kidney structure and function after damage.OBJECTIVE:To investigate renal histology and function changes following BMSC transplantation in a rat model of radiation-inducad damage.DESIGN,TIME AND SETTING:The cytological in vitro study was performed at the Laboratory of the Department of Hematology,Zhujiang Hospital from January to October 2009.MATERIALS:A total of 35 clean male Sprague Dawley rats were selected.Of them,20 were used to prepare BMSCs.The remaining was randomly assigned to a normal control,model and cell transplantation groups,with 5 in each group.METHODS:Rat BMSCs were incubated by the whole bone marrow method.When 90% cells were confluent,BMSCs were digested in trypsin for subculture.In the model and cell transplantation groups,rats were used to establish radiation-induced models,and then underwent X-ray general irradiation,at a dose of 500 cGy/min,100 cm from the target,6 Gy each,once per week,for consecutively 3 weeks.24 hours following irradiation,BMSCs of 3 passage were collected at logarithmic phase.In the cell transplantation group,1 mL cell suspension was infused into the rat caudal vein,containing 3×10~6 cells,totally three times.In the normal control and model groups,rat caudal vein received an equal volume of saline.MAIN OUTCOME MEASURES:The following parameters were measured:results of hematoxylin-eosin staining;serum and kidney malondialdehyde (MDA) content and superoxide dismutase (SOD) activity;serum creatinine and urea nitrogen levels.RESULTS:Kidney histopathology demonstrated thin renal cortex,increased number of mesenchyme,uneven renal corpuscle,and disordered structure of renal glomerulus,narrow renal glomerular vessel,partial disappeared capsular space,and degeneration and sclerosis of some glomerulus in the model group.In the cell transplantation group,renal cortex became thick,with clear structure;interstitial hyperemia and edema was significantly relieved;many complete renal corpuscles were observed;partial renal glomerulus presented degeneration and sclerosis;significant capsular space could be seen.Oxygen free radical examination results showed that compared with the model group,SOD activity was significantly higher (P ＜ 0.05),MDA levels were significantly lower (P ＜0.05) in the cell transplantation group.Renal function examination results demonstrated that compared with the model group,serum creatinine and urea nitrogen levels were significantly reduced in the cell transplantation group (P ＜ 0.05).CONCLUSION:BMSC transplantation can effectively treat renal radiation injury and improve renal function.