Morphological Changes And Mechanisms Of Kidney Transplantation Cold Preservation Injury

Bcakground and ObjectiveEnd stage renal function irreversible failure is the final stage of kidney disease,kidney transplantation is the best treatment.With the increase in the number of patients to be transplanted,some marginal kidneys will also be used for clinical transplantation.However,cold ischemic injury is an inevitable pathophysiological stage during the cold preservation of clinical kidney transplantation,which is closely related to the recovery and long-term prognosis of renal function after transplantation.The purpose of this study is to explore the clinical kidney transplantation model,cold preservation process donor kidney in the microstructure and ultrastructural morphological changes.And the breakdown of blood flow on KLF2 and its downstream and endothelial protection-related gene expression,NF-κB and its downstream genes related to inflammatory response.We will preliminary description of the clinical kidney transplantation,donor kidney morphological changes.In order to further elucidate the mechanism of cold ischemia injury of donor kidney,the results of this study have important clinical and basic research significance for the research and development of donor kidney protection,expanding the scope of donor kidney,and understanding the process of cryopreservation.MethodA total of 20 healthy male C57 BL / 6 mice were used in this study.They were divided into 4 groups.(1)Normal control(Normal),(2)Cold Storage 4h(CS 4h),(3)Cold Storage 12h(CS 12h),(4)Cold Storage 24h(CS 24h).The transplanted kidney cold preservation model was used to remove the kidneys.Detection indicator: The morphological and ultrastructural changes of the kidneys were observed.The expression levels of KLF2,NF-κB,HIF-1α,eNOS,TM,Nrf2,VCAM-1 and E-sele in mouse kidney were detected.Results(1)Changes of HE in Mouse Kidney during Cold Storage: Compared with the normal control group,the morphological structure of renal tubules,glomeruli and renal capsule was normal in the cold storage for 4h,12 h and 24 h,and no obvious morphological changes were observed.(2)Ultrastructural changes in kidneys during cold preservation: The ultrastructure of the kidneys showed obvious damage.The cryopreserved 4h group had some necrosis and shedding of the capillary glomerular capillary endothelial cells in the mouse glomerular filtration membrane.The arrangement of the microvilli of the proximal tubule was not dense.Neat,mitochondria appear atypical.In the 12 h group,the glomerular capillary endothelial cell necrosis and the degree of shedding were increased in the glomerular capillaries of the mouse.The microvilli of the mouse glomerular capillary endothelial cells were agglutinated,the chromatin condensation,the microvilli of the proximal tubule were further disordered,the number of mitochondria Further reduced,atypia increased.Cold storage 24 h group,mouse glomerular filtration membrane endothelial cells necrosis,shedding,endothelial cell nuclear condensation,chromatin condensation,foot part of the fusion,proximal tubule microvilli swelling,rupture,mitochondrial swelling,internal rupture Bubble area,the size of irregular arrangement.(3)Expression of transcription factor KLF2 mRNA in cryopreserved renal tissue: The expression of KLF2 in the renal tissue of the mice was not significantly changed in the cryopreserved group The expression of KLF2 in the renal tissue was decreased at 12 h and 24 h.The expression of KLF2 protein in cryopreserved kidney tissue was significantly lower than that in cold storage group.The expression of KLF2 protein in renal tissue was lower than that in cold storage group at 4h and 12 h group.(4)The expression of eNOS,TM,Nrf2 in cryopreserved renal tissue: The expression of eNOS,TM and Nrf2 in the kidney tissues of mice were significantly decreased at 4h,12 h and 24 h.(5)The preservation of E-sele and VCAM-1 in renal tissue: There was no significant change in the expression of E-sele in the cryopreserved group at 4h and 12 h,and the expression of E-sele in cold storage group was significantly increased.The expression of VCAM-1 in the kidneys was not significantly changed,and the expression of VCAM-1 in the cryopreserved group was significantly higher than that in the control group.(6)The changes of NF-κB in cryopreserved renal tissue: The expression of NF-κB in the cold group was not significantly changed.The expression of NF-κB in the cryopreserved group was increased and the expression of NF-κB in the 24 hours group was decreased.Conclusion(1)In the process of cold preservation of donor kidney,glomerular endothelial cell injury,mitochondrial swelling,followed by endothelial cell chromatin,agglomeration,nuclear condensation,microvilli rupture,and ultrastructural changes of podocyte fusion.(2)Downregulation of the transcription factor KLF2 and its downstream vascular protection products(eNOS,TM,etc.)may play an important role in mouse kidney cold ischemic injury.(3)Upregulation of NF-κB and its downstream inflammatory factor products(E-sele,etc.)may play an important role in mouse kidney cold ischemic injury.