Hyaluronic acid-based hydrogel scaffold without angiogenic growth factors enhances ovarian tissue function after autotransplantation in rats.

One of the problems encountered during ovarian transplantation is that the number of primordial follicles in the grafts is considerably reduced 2 d after transplantation due to post-transplantation ischemia. This study investigates if the use of hyaluronic acid-based hydrogel (HABH) with and without vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) could prevent or minimize ischemia-induced follicle loss during ovarian autotransplantation and thereby restore ovarian tissue function in the rat model. In this study, twenty four female rats were subjected to bilateral ovariectomy and were randomly divided into 3 groups for ovarian tissue autotransplantation. Group A included rats with ovarian tissue without HABH, VEGF and bFGF, group B comprised rats with ovarian tissue encapsulated with HABH and group C had rats with ovarian tissue encapsulated with HABH containing VEGF and bFGF. Three days after transplantation, the grafts were assessed through histological and hormonal analyses. Apoptotic, angiogenic and maturation genes expressions were also analyzed. The mean number of follicles in all developmental stages increased in group B (P  <  0.05). The level of FSH decreased in group B (P  <  0.05) whereas, the expression level of VEGF gene increased in group B (P  <  0.05). No significant changes were observed in the expression levels of maturation and apoptotic genes in all groups. In conclusion, ovarian encapsulation with HABH alone can prevent or minimize ischemia-induced follicle loss, preserve the follicular pool, promote follicular survival, facilitate angiogenesis, and restore hormone levels. However, its efficiency in a clinical setting and in comparison with other hydrogels needs further investigation.