Study of hormone receptors of estrogen and progesterone in cryopreserved ovarian grafts treated with adipose tissue-derived stem cells in rats

Abstract

The cryopreservation of ovarian tissue for later transplantation is a fertility preservation alternative for patients who will undergo gonadotoxic treatments. Although it's effective in preserving the endocrine function and fertility, the ovarian transplantation still considered an experimental technique because of their limited experience and the need for technical improvement. The follicular loss induced by the ischemic injury after transplantation compromises graft longevity, and treatments to increase its angiogenesis has been proposed. Cell therapy with stem cells has emerged as promising option. This study aims to assess hormone receptors of progesterone and estrogen in cryopreserved ovarian grafts treated with adipose tissue-derived stem cells (ASC). Twenty adults female Wistar rats will be submitted to bilateral oophorectomy. Both ovaries will be cryopreserved by slow freezing protocol and maintained in N2 storage for 24h. After this period, the ovaries will be thawed and a bilateral autologous transplantation with the whole ovaries without vascular anastomosis in the retroperitoneum will be performed. At this time, the animals will be divided into two groups: Gelfoam (Control) and Gelfoam + ASC (5x104 cells/ovary). In Control group, the Gelfoam will be soaked in culture medium. Euthanasia will be held between 30-35 postoperative day, always in diestrus phase of the estrous cycle. The ovarian grafts will be removed for the following analysis: histo-morphological and immunohistochemical for hormone receptors of progesterone and estrogen.