DNA methylation and histone acetylation patterns in cultured bovine adipose tissue-derived stem cells [BADSCs]

Many studies have focused on the epigenetic characteristics of donor cells to improve somatic cell nuclear transfer [SCNT]. We hypothesized that the epigenetic status and chromatin structure of undifferentiated bovine adipose tissue-derived stem cells [BADSCs] would not remain constant during different passages. The objective of this study was to determine the mRNA expression patterns of DNA methyltransferases [DNMT1, DNMT3a, DNMT3b] and histone deacetyltransferses [HDAC1, HDAC2, HDAC3] in BADSCs. In addition, we compared the measured levels of octamer binding protein-4 expression [OCT4] and acetylation of H3K9 [H3K9ac] in BADSCs cultures and different passages in vitro. In this experimental study, subcutaneous fat was obtained from adult cows immediately post-mortem. Relative level of DNMTs and HDACs was examined using quantitative real time polymerase chain reaction [q-PCR], and the level of OCT4 and H3K9ac was analyzed by flow cytometry at passages 3 [P3], 5 [P5] and 7 [P7]. The OCT4 protein level was similar at P3 and P5 but a significant decrease in its level was seen at P7. The highest and lowest levels of H3K9ac were observed at P5 and P7, respectively. At P5, the expression of HDACs and DNMTs was significantly decreased. In contrast, a remarkable increase in the expression of DNMTs was observed at P7. Our data demonstrated that the epigenetic status of BADSCs was variable during culture. The P5 cells showed the highest level of stemness and multipotency and the lowest level of chromatin compaction. Therefore, we suggest that P5 cells may be more efficient for SCNT compared with other passages

[Amniotic membrane seeded with mesenchymal adipose-derived stem cell for coverage of wound in third degree burn: An experimental study]

Stem cells are applied in the treatment of wide range of diseases and can be separated from different tissues of the body. These cells can treat diseases by cytokine and growth factor secretion and also cell differentiation. Burn wound is a challenging problem of reconstructive surgery and stem cells may help wound healing process. We designed this study to evaluate the beneficial effect of fat derived stem cells for coverage of 3[rd] degree burn wound. This study was experimental and has been done in Burn Research Center of Iran University of Medical Sciences during January 2012 to April 2013. Thirty rats randomly divided to three equal groups. Inguinal fat of 10 rats [one group] were used for preparation of autologous adipose-derived mesenchymal stem cells. Acellular amnion was used as a scaffold for stem cell transfer. Each of the thirty rats had been exposed to a cm deep 3rd degree burn on back area. 24 hours after surgery, the wound was excised and it had been covered by three conventional dressing in the first group, acellular amnion in the second group and acellular amnion seeded with adipose-derived stem cell in the third group. The rate of wound healing and pathologic characteristics was compared in all three groups. Healing rate and decrease in wounds size was significantly better in acellular amnion seeded with adipose- derived stem cells compared with other two groups at 3[rd] and 15[th] days after surgery P<0.01. Also in histopathology examination, fibroplasia and neovascularization of wounds were significantly better in stem cells group than the other two groups P<0.001. Acellular amnion seeded with adipose-derived stem cell can result in faster wound healing and better histopathology characteristic. The amnion as a scaffold and the fat derived stem cells as healing accelerator are recommended for coverage of the 3rd degree burn wounds after excision and it may reduce the need for skin graft