Rossella Masciangelo1, Camille Hossay1, Maria Costanza Chiti1, Diego Daniel Manavella1, Christiani Andrade Amorim1, Jacques Donnez2, Marie-Madeleine Dolmans3,4. 1. Pôle de Recherche en Gynécologie, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Avenue Mounier 52, bte. B1.52.02, 1200, Brussels, Belgium. 2. Société de Recherche pour l'Infertilité, Avenue Grandchamp 143, 1150, Brussels, Belgium. 3. Pôle de Recherche en Gynécologie, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Avenue Mounier 52, bte. B1.52.02, 1200, Brussels, Belgium. marie-madeleine.dolmans@uclouvain.be. 4. Département de Gynécologie, Cliniques Universitaires St. Luc, Avenue Hippocrate 10, 1200, Brussels, Belgium. marie-madeleine.dolmans@uclouvain.be.
Abstract
PURPOSE: Our aim was to elucidate the mechanisms involved in follicle activation of the ovarian reserve after human ovarian tissue transplantation, with specific focus on the role of the effectors of the PI3K (mTOR and FOXO1) and Hippo (YAP) signaling pathways and whether they are somehow altered. METHODS: Frozen-thawed ovarian tissue was collected from six women (age 25-35 years) undergoing surgery for non-ovarian pathologies and divided into 4 fragments in each case: one for non-grafted controls and three for grafting to immunodeficient mice for 3, 7 and 21 days. The tissue was processed for hematoxylin and eosin staining, immunohistochemistry and immunofluorescence at different timepoints before and after grafting. Activation of the PI3K and Hippo signaling pathways was investigated by analysis of mTOR phosphorylation, FOXO1 cytoplasmic localization and YAP nuclear localization. RESULTS: No change in mTOR levels was observed in primordial follicles post-transplantation, but a significant upturn was recorded in growing follicles compared with primordial follicles, irrespective of grafting time. A higher percentage of primordial follicles was also found with FOXO1 in the cytoplasm after 3 days of transplantation than in non-grafted controls. Finally, a greater proportion of primordial follicles was detected with YAP in the nucleus at all timepoints after grafting. CONCLUSIONS: This study supports the hypothesis that follicle activation may occur as an early event after transplantation, with follicle growth and death both contributing to the burnout phenomenon. This is the first time that the effectors of the PI3K and Hippo pathways have been investigated in grafted human ovarian tissue and their role in burnout documented.
PURPOSE: Our aim was to elucidate the mechanisms involved in follicle activation of the ovarian reserve after human ovarian tissue transplantation, with specific focus on the role of the effectors of the PI3K (mTOR and FOXO1) and Hippo (YAP) signaling pathways and whether they are somehow altered. METHODS: Frozen-thawed ovarian tissue was collected from six women (age 25-35 years) undergoing surgery for non-ovarian pathologies and divided into 4 fragments in each case: one for non-grafted controls and three for grafting to immunodeficient mice for 3, 7 and 21 days. The tissue was processed for hematoxylin and eosin staining, immunohistochemistry and immunofluorescence at different timepoints before and after grafting. Activation of the PI3K and Hippo signaling pathways was investigated by analysis of mTOR phosphorylation, FOXO1 cytoplasmic localization and YAP nuclear localization. RESULTS: No change in mTOR levels was observed in primordial follicles post-transplantation, but a significant upturn was recorded in growing follicles compared with primordial follicles, irrespective of grafting time. A higher percentage of primordial follicles was also found with FOXO1 in the cytoplasm after 3 days of transplantation than in non-grafted controls. Finally, a greater proportion of primordial follicles was detected with YAP in the nucleus at all timepoints after grafting. CONCLUSIONS: This study supports the hypothesis that follicle activation may occur as an early event after transplantation, with follicle growth and death both contributing to the burnout phenomenon. This is the first time that the effectors of the PI3K and Hippo pathways have been investigated in grafted human ovarian tissue and their role in burnout documented.
Authors: D D Manavella; L Cacciottola; C M Desmet; B F Jordan; J Donnez; C A Amorim; M M Dolmans Journal: Hum Reprod Date: 2018-02-01 Impact factor: 6.918
Authors: D D Manavella; L Cacciottola; S Pommé; C M Desmet; B F Jordan; J Donnez; C A Amorim; M M Dolmans Journal: Hum Reprod Date: 2018-06-01 Impact factor: 6.918
Authors: Luciana Cacciottola; Thu Y T Nguyen; Maria C Chiti; Alessandra Camboni; Christiani A Amorim; Jacques Donnez; Marie-Madeleine Dolmans Journal: J Clin Med Date: 2020-09-15 Impact factor: 4.241