Comparison of the Ovary and Kidney as Sites for Islet Transplantation in Diabetic Rats.

BACKGROUND: Currently, the most commonly used site for clinical islet transplantation is the liver although it is far from being an ideal site. Low oxygen tension and the induction of an inflammatory response impair islet implantation and lead to significant early loss of islet. The present study aimed to investigate and compare the efficacy of islet transplantation to the ovary and kidney subcapsule in diabetic rats. METHODS: The study was performed with 3 groups of rats (control, ovary, and kidney subcapsule) including 6 Sprague female rats each. Diabetes model was created with the use of streptozotocin, and blood glucose levels of the rats were measured after 72 hours. Thirty days after the transplantation, blood samples were obtained from the rats, and then pancreas, kidney, and ovary specimens were fixed in 10% formaldehyde and the experiment completed. After staining with hematoxylin and eosin, the tissue samples were morphologically evaluated by a specialist histopathologist. RESULTS: Changes in mean blood glucose and C-peptide levels were statistically significant in the ovary and kidney subcapsule groups. Histologic examination revealed that granulosus insulin-bearing cells were detected in the islet grafts of both ovary and kidney subcapsule groups. The renal subcapsule group had inflammation signs on histologic examination. The islet cells of both ovary and renal subcapsule groups had no vacuolization. CONCLUSIONS: We showed that the ovary might be a new site for islet transplantation. Further research should be done on whether the initial results of this study can be reproduced in larger numbers of animal models and eventually in humans.

Effect of stem cell application on Asherman syndrome, an experimental rat model.

PURPOSE: We evaluate the effect of stem cells to induce endometrial proliferation and angiogenesis on Asherman Syndrome (AS). METHODS: The experimental study was performed in stemcell research laboratory. Forty Wistar-Albino rats were divided according to groups. In group1 (n = 10) to establish the model; trichloroacetic acid was injected to right uterine horn. Two weeks later, intrauterine synechia was confirmed. In group2 (n = 10), 2 weeks later, 2 × 106 mesenchymal stem cells (MSC) were injected into right uterine horn followed by three intraperitoneal injections of MSCs. In group3 (n = 10), daily oral estrogen was initiated on the second week. In group4 (n = 10), MSC injections and oral estrogen was given together. The amount of fibrosis, vascularisation, inflammation and immunohistochemical staining with vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA) and Ki-67 were evaluated in the uterine tissues. RESULTS: In all treatment groups; fibrosis decreased but vascularisation and immunhistohemical stainings increased in the experimental side. The amount of fibrosis, vascularisation, Ki-67 and PCNA scores were similar between group2 and 3. In group4, comparing to group2, less fibrosis but more Ki-67, PCNA and VEGF staining was observed. CONCLUSION: Stem cells, when added to estrogen, are a highly effective alternative to induce regeneration of endometrium in Asherman Syndrome therapy.