Restoration Of Endocrine Function Research Articles

Exploring the Frontiers of Ovarian Tissue Cryopreservation: A Review.

Objective: This paper serves as an up-to-date narrative review of the most effective methods and outcomes of ovarian tissue cryopreservation (OTC) with new data comparing this method to oocyte and embryo cryopreservation as well as its utility in restoration of endocrine function. Background: Data on OTC are becoming more available as more patients are achieving cancer remission and choosing to use their cryopreserved tissue to conceive or restore endocrine function. With OTC only recently becoming a non-experimental method of fertility preservation, it is important to evaluate, compare, and optimize current practices to improve live birth outcomes. Methods: A literature search of meta-analyses, systematic reviews, case series, retrospective studies, and randomized control trials was performed using the PubMed database with multiple search terms. Discussion: Current practices and outcomes of OTC remain heterogeneous, though they are becoming more streamlined with the emerging data on successful live births. Multiple aspects of OTC have been studied to optimize protocols, particularly methods of cryopreserving, in vitro maturation, and transplantation. In vitro follicle maturation is a novel application with emerging data on methods and outcomes. OTC is a versatile method not only for fertility preservation but also for hormone restoration as well. With wider usage of OTC, ethical dilemmas will need to be addressed. Conclusions: OTC can be used as fertility preservation for a variety of patients. Recent studies suggest it may be comparable to embryo cryopreservation, but with growing data on live births, comparative studies should continue to be performed. In vitro follicle maturation (IVFM) is a promising application of ovarian tissue harvesting. Data are lacking on cost-effectiveness, patient satisfaction, and morbidity associated with OTC.

Enhancement of Vascularization and Ovarian Follicle Survival Using Stem Cells in Cryopreserved Ovarian Tissue Transplantation-A Systematic Review.

The increase in cancer survival rates has put a focus on ensuring fertility preservation procedures for cancer patients. Ovarian tissue cryopreservation presents the only option for prepubertal girls and patients who require immediate start of treatment and, therefore, cannot undergo controlled ovarian stimulation. We aimed to provide an assessment of stem cells' impact on cryopreserved ovarian tissue grafts in regard to the expression of growth factors, angiogenesis promotion, tissue oxygenation, ovarian follicle survival and restoration of endocrine function. For this systematic review, we searched the Scopus and PubMed databases and included reports of trials using murine and/or human cryopreserved ovarian tissue for transplantation or in vitro culture in combination with mesenchymal stem cell administration to the grafting site. Of the 1201 articles identified, 10 met the criteria. The application of stem cells to the grafting site has been proven to support vascular promotion and thereby shorten the period of tissue hypoxia, which is reflected in the increased number of remaining viable follicles and faster recovery of ovarian endocrine function. Further research is needed before implementing the use of stem cells in OT cryopreservation and transplantation procedures in clinical practice. Complex ethical dilemmas make this process more difficult.

A 16-year bicentric retrospective analysis of ovarian tissue cryopreservation in pediatric units: indications, results, and outcome.

Cancer treatments of the last decades improve the survival rate of children and adolescents. However, chemo- and radiotherapy result in gonadal damage, leading to acute ovarian failure and sterility. The preservation of fertility is now an integral part of care of children requiring gonadotoxic treatments. Ovarian tissue cryopreservation (OTC) is an effective fertility preservation option that allows long-term storage of primordial follicles, subsequent transplantation, and restoration of endocrine function and fertility. The efficacy of this technique is well-demonstrated in adults but the data are scarce for pediatric patients. Currently, OTC represents the only possibility of preserving the potential fertility in prepubertal girls. This is a retrospective study of OTC practice of two French centers from January 2004 to May 2020.A total of 72 patients from pediatric units underwent cryopreservation of ovarian tissue before gonadotoxic therapy for malignant or non-malignant diseases. The ovarian cortex was cut into fragments and the number of follicles per square millimeter was evaluated histologically. The long-term follow-up includes survival rate and hormonal and fertility status. The mean age of patients at OTC was 9.3 years [0.2-17] and 29.2% were postpubertal; 51 had malignant diseases and 21 had non-malignant diseases. The most frequent diagnoses included acute leukemia, hemoglobinopathies, and neuroblastoma. Indication for OTC was stem cell transplantation for 81.9% (n = 59) of the patients. A third of each ovary was collected for 62.5% (n = 45) of the patients, a whole ovary for 33.3% (n = 24) of the patients, and a third of one ovary for 4.2% (n = 3) of the patients. An average of 17 fragments [5-35] per patient was cryoconserved. A correlation was found between the age of the patients and the number of fragments (p < 0.001). More fragments were obtained from partial bilateral harvesting than from whole ovary harvesting (p < 0.05). Histological analysis of ovarian tissue showed a median of 6.0 primordial follicles/mm2 [0.0-106.5] and no malignant cells were identified. A negative correlation was found between age and follicular density (p < 0.001). Median post-harvest follow-up was 92 months [1-188]. A total of 15 girls had died, 11 were still under treatment for their pathology, and 46 were in complete remission. Of all patients, 29 (40.2%) were subjected to a hormonal status evaluation and 26 were diagnosed with premature ovarian insufficiency (POI) (p < 0.001). One patient had undergone thawed ovarian tissue transplantation. OTC should be proposed to all girls with high risk of developing POI following gonadotoxic therapies in order to give them the possibility of fertility and endocrine restoration.

Laparoscopic ovarian tissue harvesting and orthotopic ovarian cortex grafting for fertility preservation: less is more

To describe our surgical techniques for laparoscopic ovarian tissue harvesting and orthotopic ovarian cortex grafting (LOOCG). This video article uses surgical cases to demonstrate the detailed surgical techniques. Institutional Review Board approval was not required for this video presentation. University hospital. Patients presenting with indication for fertility preservation by means of ovarian tissue harvesting and orthotopic ovarian cortex grafting (in case of setting up a high risk of gonadotoxicity treatment or patients presenting with a pathology with risk of premature ovarian failure). Ovarian tissue harvesting: The entire ovary is harvested by placing an EndoGIA stapler to ensure the control of infundibulopelvic ligament and then, after reloading, the section of the mesovarium. LOOCG one-step procedure: A large and superficial incision of the peritoneum is performed to create a peritoneal pocket. The fragments of ovarian cortex are secured with the use of nonresorbable surgical wire (Prolene 5.0) and introduced into the peritoneal pocket. The peritoneum is not closed after placing the graft. Value and feasibility of LOOCG. Restoration of endocrine function and fertility results. Thirty-four patients were included from November 2011 to October 2017. LOOCG restored ovarian endocrine activity in 88.2% of cases. Ten patients had become pregnant (29.4%), and the same number gave birth to at least one child. Our surgical approach is simple, safe, and reproducible and seems to be as effective as previously described techniques. It deserves to be proposed to patients eligible for ovarian cortex grafting.

Restoration of Endocrine Function and Fertility with Orthotopic Tubal—Ovarian Allotransplant as the Anatomical-Functional Unit in Rabbits

The aim of this study was to re-establish endocrine and reproductive function in tubal-ovariectomized rabbits using orthotopic tubal–ovary allotransplants (OT-OA). Fifty-five New Zealand White nonconsanguineous rabbits were used and allocated into five experimental groups: Each group comprised donors submitted to right salpingo-oophorectomy that served as the donated allograft. In group 1 no cyclosporin (CsA) was administered and rabbits were submitted to left salpingo-oophorectomy (LSO). Group 2 was the allotransplant group and did not receive CsA. Group 3 was the allotransplant group with CsA. They were submitted to bilateral salpingo-oophorectomy followed by OT-OA. CsA of 10 mg/kg/day was administered to rabbits for the first 21 days and 5 mg/kg/day for the remainder of the study. Group 4 received CsA just as for group 3 and was submitted to LSO. During the study the following were measured: estradiol (E2), progesterone (P4), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and histopathological study of the uteri, tubes, and ovaries. Groups 1, 3, and 4 showed a significant increase in serum E2 and P4 levels corresponding to the second week of gestation, compared to group 2 (p < < x >.05). < i > Group < /i > 2 < i > showedasignificantincreaseinserumLHandFSHlevelsduringweek < /i > 10 < i > comparedtoserumLHandFSHlevelsingroups < /i > 1, 3, < i > and < /i > 4 (< /x > p <.05). In group 3, three rabbits did not reject the allotransplant, one rabbit became pregnant, and endocrine function was re-established in two rabbits. It can be concluded that OT-OA together with CsA administration re-establishes endocrine function and fertility.

Restoration of Endocrine Function and Ovulation After a Heterotopic Ovarian Transplant in the Inguinal Region of Rabbits Using a Vascular Microsurgical Technique

The aim of this study was to define an experimental model in rabbits for subcutaneous heterotopic ovarian autotransplants and allotransplants in the inguinal region using a microvascular technique to restore endocrine function and ovulation. Forty sexually mature New Zealand white receptor rabbits and 20 donating Californian rabbits were divided into two experimental models: model A; autogenic model—control group 1 ( n = 10), right ovariectomy; group II ( n = 10), heterotopic ovarian autotransplant with peritoneal pouch plus left ovariectomy; model B: allogenic model—donator group III ( n = 10), right ovariectomy with peritoneal tissue; receptor group ( n = 10), ovarian heterotopic allotransplant with peritoneal pouch and bilateral ovariectomy, without immunosuppression; group IV donator ( n = 10), receptor ( n = 10) using the same procedure as in group III, administering cyclosporine 4 mg/kg/d intramuscularly and prednisone 1 mg/kg/d PO for 28 days. Ovarian function was assessed in the transplanted ovary after stimulation with human chorionic gonadotropin (100 IU). Exfoliative vaginal cytology was done, serum estradiol (E 2) and progesterone (P 4) were measure, and a histological study of ovaries and uteri was done. Late vascular permeability was 73.3%. Serum E 2 and P 4 levels during the poststimulation period were extremely low exclusively in group III ( P < .05). In all viable grafts, the histological study showed follicular development and presence of luteal bodies. In the uteri, the endometrium was proliferative and vaginal cytology showed the karyopicnotic index was >20%. Endocrine function and ovulation were restored in the heterotopic transplanted ovary. Allogenic heterotopic ovarian transplants are indicated in women with gonadal dysgenesia or premature surgical menopause.

Restoration of Endocrine Function and Fertility With a Tubo-Ovarian Autotransplant as the Anatomical-Functional Unit in Rabbits Using a Vascular Microsurgical Technique

Infertility has been considered a global public health problem in many countries worldwide. Our objective was to restore endocrine function and fertility in tubal-oophorectomized rabbits using an orthotopic tubal-ovarian vascularized autotransplant model as the anatomical-functional unit while employing a microvascular surgical technique. Twenty New Zealand white (NZW) sexually mature female rabbits and four male NZW rabbits of proven fertility were divided into two study groups. In group I ( n = 10), a left salpingo-oophorectomy was performed. Group II ( n = 10) was subjected to a bilateral salpingo-oophorectomy, plus a right orthotopic tubal-ovarian autotransplant. Our testing variables were vascular and tubal-anastomoses permeability, estradiol (E 2) and progesterone (P 4) serum levels, pregnancy, number of offspring, histopathological study of the uteri, fallopian tubes, and ovaries. One hundred percent immediate permeability of the tubal anastomoses was achieved, while late permeability was found to be 64%. Immediate permeability of vascular anastomoses was 90%, and late permeability was recorded at 80%. E 2 serum levels in both groups at different times showed no statistically significant differences. In the case of P 4, a small difference was found during pregnancy, especially greater in the control group ( P < .05). In the autotransplanted group, four rabbits became pregnant (44%). Endocrine function and fertility were restored in the rabbits with the tubal-ovarian transplant as the anatomical-functional unit. The use of isotransplants and allotransplants should be considered a therapeutic alternative in the infertile woman with irreparable bilateral tubal damage, ovarian dysgenesis, surgical absence of ovaries and fallopian tubes, or when the conventional IVF/TE in these cases has been unsuccessful.

The Recruitment of Bone Marrow-Derived Cells to Sites of Pancreatic ^|^beta;-cell Injury and the Restoration of Endocrine Function

The Recruitment of Bone Marrow-Derived Cells to Sites of Pancreatic ^|^beta;-cell Injury and the Restoration of Endocrine Function

Changes in metabolism and hormone trafficking during exposure of endocrine cells to elevated ammonium

Endocrine cell cultures have potential in bioprocessing, for the production of biologically active hormones, and in tissue engineering, for the development of implantable artificial tissues for long-term restoration of endocrine function. To optimize such systems, it is necessary to develop a thorough understanding of how inherently present environmental stresses, such as nutrient depletion and metabolite accumulation, affect the cells. This work focuses on the effects of the metabolite ammonium on indicators of endocrine cell metabolism and on the processing, storage and secretion of regulated secretory proteins. Experiments were conducted on recombinant insulin-producing mouse pituitary AtT-20 cells and mouse insulinoma βTC3 cells. Exposure for 24-48 hours to 6 mM of exogenous ammonium resulted in higher rates of glucose consumption by both AtT-20 and βTC3 cells, while the formation of additional ammonium generally decreased relative to ammonium-free controls. When βTC3 cells were discharged of their intracellular insulin stores, the presence of ammonium during a subsequent recharge completely inhibited addition of new insulin-related peptides to the stores, as we had observed previously for both cell lines. There was a correlation between insulin-related peptides stored in βTC3 cells during recharging and the amount that could be released upon secretagogue stimulation. Using a combination of radioimmunoassay and high performance liquid chromatography, we found that intracellular insulin and insulin-related peptides changed in the same fashion. Intracellular mechanisms that may be producing the observed results are discussed.