The neovascularization effect of dedifferentiated fat cells.

Mature adipocyte-derived dedifferentiated fat (DFAT) cells can be prepared efficiently and with minimal invasiveness to the donor. They can be utilized as a source of transplanted cells during therapy. Although the transplantation of DFAT cells into an ischemic tissue enhances angiogenesis and increases vascular flow, there is little information regarding the mechanism of the therapeutic angiogenesis. To further study this, mice ischemic hindlimb model was used. It was confirmed that in comparison with the adipose derived stem cells and fibroblasts, the transplantation of DFAT cells led to a significant improvement in the blood flow and increased mature blood vessel density. The ability of DFAT cells to secrete angiogenic factors in hypoxic conditions and upon co-culture with vascular endothelial cells was then examined. Furthermore, we examined the possibility that DFAT cells differentiating into pericytes. The therapeutic angiogenic effects of DFAT cells were observed by the secretion of angiogenic factors and pericyte differentiation by transforming growth factor ß1 signalling via Smad2/3. DFAT cells can be prepared with minimal invasiveness and high efficiency and are expected to become a source of transplanted cells in the future of angiogenic cell therapy.

Therapeutic potential of mature adipocyte-derived dedifferentiated fat cells for inflammatory bowel disease.

PURPOSE: Our previous studies demonstrated that mature adipocyte-derived dedifferentiated fat (DFAT) cells possess similar multipotency as mesenchymal stem cells. Here, we examined the immunoregulatory potential of DFAT cells in vitro and the therapeutic effect of DFAT cell transplantation in a mouse inflammatory bowel disease (IBD) model. METHODS: The effect of DFAT cell co-culture on T cell proliferation and expression of immunosuppression-related genes in DFAT cells were evaluated. To create IBD, CD4+CD45RBhigh T cells were intraperitoneally injected into SCID mice. One week later, DFAT cells (1 × 105, DFAT group) or saline (Control group) were intraperitoneally injected. Subsequently bodyweight was measured every week and IBD clinical and histological scores were evaluated at 5 weeks after T cell administration. RESULTS: The T cell proliferation was inhibited by co-cultured DFAT cells in a cell density-dependent manner. Gene expression of TRAIL, IDO1, and NOS2 in DFAT cells was upregulated by TNFα stimulation. DFAT group improved IBD-associated weight loss, IBD clinical and histological scores compared to Control group. CONCLUSION: DFAT cells possess immunoregulatory potential and the cell transplantation promoted recovery from colon damage and improved clinical symptoms in the IBD model. DFAT cells could play an important role in the treatment of IBD.

Establishment of a new anal sphincter injury model in rats based on cardiotoxin.

BACKGROUND/PURPOSE: Mainstream models for anal sphincter injury use large animals. We developed a simple and stable anal sphincter injury model in a small animal (i.e., rats) to obtain manometry measurements by using a miniaturized probe and applying cardiotoxin. METHODS: The histological structure of the anal canal was evaluated by using manometry in normal rats (n=40). We damaged the internal and external anal sphincters by locally administering snake poison (cardiotoxin; 20 uM, 100µL 8 points). We evaluated the anal canal function through manometry measurements (n=5) and examined the histology using hematoxylin-eosin staining (at each time point, n=3; total n=15). RESULTS: The manometry parameters and structure of the anal canal of normal rats were similar to those of humans, because rats have resting pressure, rectoanal reflex in the manometry, and an external and internal anal sphincter. After inducing injury, the following findings were observed: rhythmic wave loss and a remarkable reduction in the anal sphincter resting pressure; and local bleeding and advanced infiltration of the inflammatory cells (day 1) and the loss of muscle fibers (day 3). CONCLUSION: This new rat model will contribute to increasing the knowledge on the anal canal.

Non-promoter DNA hypermethylation of Zygote Arrest 1 (ZAR1) in neuroblastomas.

BACKGROUND: The comprehensive methylation analysis of tumor-specific differently methylated regions in malignant melanomas and brain tumors has led to the identification of non-promoter hypermethylation of zygote arrest 1 (ZAR1). To search the non-promoter ZAR1 hypermethylation in neuroblastomas, we analyzed the levels of the methylation and transcript expression of ZAR1. METHODS: The MassARRAY® EpiTYPER (Sequenom Inc., San Diego, CA, USA) system was optimized to determine the quantitative methylation levels of ZAR1 for 12 neuroblastoma cell lines, 23 neuroblastoma samples and four adrenal samples. ZAR1 expression levels were evaluated through a quantitative, real-time reverse transcription-polymerase chain reaction. The quantitative methylation levels of ZAR1 were subjected to correlation studies with the established markers of progressive disease and outcome. RESULTS: Strikingly, the hypermethylation of ZAR1 regions and ZAR1 expression levels was observed in the neuroblastoma cell lines and neuroblastoma samples, compared to the adrenal samples. Somatic changes in ZAR1 methylation and ZAR1 expression were found in all three neuroblastoma patients. In the ZAR1 regions, poor-outcome tumors that were MYCN-amplified and/or Stage 3 or 4 and/or the age at diagnosis was≥18months, and/or showed an unfavorable histology were frequently hypermethylated. CONCLUSION: Our results indicate that the hypermethylation of ZAR1 regions is extremely frequent in neuroblastomas and correlates with established markers of progressive disease and outcome.

Effect of combined treatment with FK506, FTY720, and ex vivo graft irradiation in rat small bowel transplantation: expression of mucosal addressin cell adhesion molecule-1.

We studied the effect of the combined treatment with FK506, FTY720, and ex vivo graft irradiation. Five groups of SBT animals were studied on days 3, 5, and 7 after operation (untreated, FK506, FTY720, FK506 + FTY720, FK506 + FTY720 + irradiation). Indirect immunoperoxidase staining was performed against CD4 and MAdCAM-1. The numbers of CD4 positive cells in allografts were also analyzed by flow cytometry. The graft survival was prolonged in all of the FK506- and FTY720-treated groups. SBT allografts treated by FK506 and FTY720 demonstrated less infiltration of CD4 positive cells, but the irradiation group did not show any effects on its expression. In FK506- and FTY720-treated groups, MAdCAM-1 expression on the HEVs in PPs was up-regulated, and its expression on the ECVs in the LP was down-regulated compared with other allograft groups. Irradiation did not show any effects on MAdCAM-1 expression on both HEVs in PPs and ECVs in LP. FK506 and FTY720 prevented the infiltration of CD4 positive cells, the down-regulation of MAdCAM-1 expression on HEVs in PPs, and the up-regulation of MAdCAM-1 expression on ECVs in LP during the early phase of SBT.

Mouse embryonic stem cells give rise to gut-like morphogenesis, including intestinal stem cells, in the embryoid body model.

Embryonic stem (ES) cells have been proposed as candidates for cell replacement therapy in patients with intestinal failure because these cells can be expanded indefinitely without losing their pluripotent phenotype. We investigated the differentiation capacity of mouse ES cells into gut-like structures, including intestinal stem cells, and defined culture conditions for efficient induction of formation of these structures. ES cell-derived gut-like structures (ES-guts) were reproducibly induced in developing embryoid bodies (EBs) by day 21 of differentiation culture. ES-guts contained an endodermal epithelium, a smooth muscle layer, interstitial cells of Cajal, and enteric neurons and showed spontaneous contraction. Transplantation of ES-guts under the kidney capsules of immunodeficient mice induced formation of highly differentiated epithelium composed of absorptive cells and goblet cells in the grafts. Immunoreactivity for Musashi-1 (Msi-1), a marker of intestinal stem cells, was detected in 1.9% of the columnar epithelial cells in the graft. Culture with 0.1% dimethyl sulfoxide increased the numbers of ES-guts in EBs, and serum-replacement (SR) culture, in comparison to standard ES culture containing 15% serum, increased the area ratio of ES-guts to EBs. SR culture also promoted maturation of epithelium to form a single layer of columnar epithelial cells, including absorptive cells and goblet cells. Expression of Msi-1 mRNA and protein was significantly enhanced when EBs were cultured under SR conditions. In conclusion, SR conditions efficiently induce formation of ES-guts and promote differentiation of epithelium, including intestinal stem cells. These results suggest the feasibility of cell-based therapy for intestinal failure based on ES cell culture systems.