Establishment of Murine Model of Kidney Failure Induced by Severe Ischemia-Reperfusion Injury Useful to Evaluate Transplantation and Regenerative Therapies.

BACKGROUND: Severe ischemia-reperfusion injury (SIRI) seems to be the key factor that can significantly affect the function of both native kidneys and renal allografts. Therefore, the development of a successful strategy is of a paramount importance in both basic and clinical research. METHODS: To determine the effects of SIRI on the native kidney function, a murine model was planned as follows: group 1 (n = 6) mice underwent to nephrectomy plus ischemia-reperfusion injury for 30 minutes; group 2 (n = 6) mice underwent to nephrectomy without ischemia-reperfusion injury and thus served as sham controls for SIRI. The results of serum creatinine (SCr) were analyzed using Mann-Whitney U tests to calculate the significance between mean values. Survival between groups was measured by Kaplan-Meier test. RESULTS: To reliably achieve an elevation of SCr levels animals were exposed to a SIRI. The values of SCr increased from 0.35 (SD, 0.09) mg/dL to about 2-fold within 2 days and 3-fold within the following 5 days. Under these given conditions the mice displayed signs and histologic findings of severe kidney damage. The survival rate was about 83% of the animals within a week, and they showed no capacity of complete spontaneous self-regeneration. CONCLUSIONS: In this study, we aim to establish a murine model with extensive structural kidney damage and significant elevation of SCr levels, which could be used in basic and translational research of transplantation and regenerative therapies.

The role of endothelial cells on islet function and revascularization after islet transplantation.

Islet transplantation has become a widely accepted therapeutic option for selected patients with type 1 diabetes mellitus. However, in order to achieve insulin independence a great number of islets are often pooled from 2 to 4 pancreata donors. Mostly, it is due to the massive loss of islets immediately after transplant. The endothelium plays a key role in the function of native islets and during the revascularization process after islet transplantation. However, if a delayed revascularization occurs, even the remaining islets will also undergo to cell death and late graft dysfunction. Therefore, it is essential to understand how the signals are released from endothelial cells, which might regulate both differentiation of pancreatic progenitors and thereby maintenance of the graft function. New strategies to facilitate islet engraftment and a prompt revascularization could be designed to intervene and might lead to improve future results of islet transplantation.