Effects of sodium alginate capsules as 3D scaffolds on hormones and genes expression in preantral follicles of mice compared to 2D medium: An experimental study

Background: The improvement of in vitro maturation methods, which can activate the preantral follicle growth, plays a crucial role in the production of mature oocytes in reproductive technology. Objective: To evaluate the different concentrations of 3D scaffolds of sodium alginate on hormones and gene expression in mice preantral follicles. Materials and Methods: Immature female BALB/c mice (12-14 days) were sacrificed. The follicles were removed mechanically and transferred into α minimal essential medium with 5% fetal bovine serum. The preantral follicles were incubated with different concentrations of sodium alginate (0.25%, 0.5%, and 1%) and 2D medium for 12 days. The follicles were examined for antral formation following the 10th day and the diameter on days 6th and 12th. The levels of hormones (AMH, androstenedione, 1

Vitrification of Germinal Vesicle Stage Oocytes

In order to cryopreserve germinal vesicle (GV) stage oocytes, we first need to develop a novel container for keeping large quantities of GV oocytes, because of collecting them as cumulus oocytes complexes (COCs) that have bigger size and larger volume than oocytes themselves, and second modify a protocol for optimizing vitrification of them. In this mini-review, we describe our recent progress for attaining these objectives. When 65 bovine COCs having GV oocytes could be placed on a sheet of nylon mesh, and plunged directly into liquid nitrogen for vitrification, the recovery rate was significantly higher compared with that in 15 ones on the electron microscope (EM) grid as a control, followed by obtaining the resultant cleavage and developmental rates after in vitro fertilization and culture (IVFC) without significant difference. Using bovine and murine oocytes, we found that a step-wise manner to expose them with the vitrification solution increased rates of in vitro maturation, subsequent development to blastocysts and hatching/hatched blastocysts after IVFC. Our results show that nylon mesh is an alternative material for cryopreserving large quantities of bovine GV oocytes, and that a step-wise exposure to cryoprotectants may have befit for decreasing disadvantage during vitrification

The boosting effects of melatonin on the expression of related genes to oocyte maturation and antioxidant pathways: a polycystic ovary syndrome- mouse model

Abstract Background Melatonin, as a free radical scavenger exhibiting genomic actions, regulates the antioxidant genes expression and apoptosis mechanisms. In polycystic ovary syndrome (PCOS) patients, an imbalance between free radicals and antioxidants in follicular fluid leads to oxidative stress, aberrant folliculogenesis, and intrinsic defects in PCOS oocytes. In this experimental mouse model study, oocytes of PCOS and the control groups were cultured in different melatonin concentrations (10− 5, 10− 6, and 10− 7 M) to investigate the expression of oocyte maturation-related genes (Gdf9/Bmp15), antioxidant-related genes (Gpx1/Sod1), apoptotic biomarkers (Bcl2/Bax) and total intracellular ROS levels. Results Gdf9 and Bmp15, Gpx1 and Sod1 were up-regulated in PCOS and control oocytes cultured in all melatonin concentrations compared to those cultured in IVM basal medium (P < 0.05). A significant decrease in the total ROS level was observed in all groups cultured in the supplemented cultures. Melatonin increased Bcl2 and decreased Bax gene expression in PCOS and control oocytes compared to non-treated oocytes. Conclusions Melatonin increased antioxidant gene expression and regulated the apoptosis pathway, effectively reducing the adverse effects of culture conditions on PCOS oocytes. Furthermore, it influenced the expression of oocyte maturation-related genes in PCOS, providing valuable support during the IVM process

Age-Associated Changes on Axonal Regeneration and Functional Outcome after Spinal Cord Injury in Rats

This study was conducted to evaluate the association between aging and regenerative potential of spinal cord injury. Three groups of male Sprague-Dawley rats, including young (40 days), mature (5-6 months) and old (28-29 months) were spinally hemisected at the L1 level. The locomotor performance was assessed weekly for eight weeks after lesion using locomotors' rating scale developed by Basso, Bresnahan and Beattie (BBB). In the tracing study, retrograde labeled neuron was counted in the lateral vestibular nucleus for axonal regeneration. From 4-8 weeks, the functional recovery of the young and mature age rats was significantly increased in comparison to the old age group. At 8 weeks, young and mature animals achieved a plateau score of (mean ± SD), 17 ± 1.47 and 16.8 ± 0.70 respectively, and the old rats reached an average score of 13.8±1.63 (P<0.05). The mean number of labeled neurons in the vestibular nucleus in the young group (mean ± SD): 32.05 ± 1.03 increase significantly compared to the older age group 5.01 ± 1.31 (P<0.05). Current findings suggest that axonal repair and functional improvement decrease in aged animals after partial spinal cord injury. Thus, the aging process may affect the regenerative capacity of the injured central nervous system, and axonal regeneration is age dependent

Remyelination of the Corpus Callosum by Olfactory Ensheathing Cell in an Experimental Model of Multiple Sclerosis

Multiple Sclerosis (MS) causes loss of the myelin sheath, which leads to loss of neurons. Regeneration of myelin sheath stimulates axon regeneration and neurons’ survival. In this study, olfactory ensheathing cell (OEC) transplantation is investigated to restore myelin sheath in an experimental model of MS in male mice.OECs were isolated from the olfactory mucosa of seven-day-old infant rats and cultured. Then, cells were evaluated and approved by flow cytometry by p75 and GFAP markers. A total of 32 mice (C57BL /6) were studied in four groups; 1) without any treatment (control), 2) Sham (receiving PBS), 3) MS model and 4) MS and OEC transplantation. MS was induced by adding Cuprizon in the diet of animals for six weeks. After the expiration of 20 days, histologic analysis was performed with approval of the presence of cells in the graft area and the removal of myelin and myelin regeneration with two types of luxal fast blue (LFB) staining and immunohistochemistry. The purity of the cells ensheathing the olfactory was 90%.  There was a significant difference in Myelin percentage of PBS and OEC recipient groups (P≤0.05). MBP and PLP of the myelin sheath in the group receiving OECs were more than MS group.According to the findings, in MS model MBP and PLP of the myelin sheath is reduced. In the group receiving OECs, it was returned to a normal level significantly compared to the sham group received only PBS significant differences were observed. The OECs transplantation can improve myelin restoration

The Effect of Fetal Olfactory Mucosa on Tissue Sparing and Locomotor Recovery after Spinal Cord Hemisection in Rats

Objective: Olfactory ensheathing cells (OECs) has been shown to have a neuroprotectiveeffect after transplanted in brain and spinal cord injury (SCI). This study was conductedto determine the possible beneficial results of transplantation of fetal olfactorymucosa (FOM) that was the source of OECs in the recovery of locomotor function andin spinal tissue sparing after spinal cord hemisection.Materials and Methods: Forty-eight adult female Sprague-Dawley rats were spinallyhemisected at the L1 level and were randomized into the three groups of 16 animals.The first group, immunosuppressed injured animals were received cyclosporine A (CsA)and FOM graft. The second group was received CsA and fetal respiratory mucosa(FRM) graft, and the control group; non-immunosuppressed rats were received salineand gel foam. Locomotor performance was assessed weekly for 8 weeks after lesion,using locomotive rating scale developed by Basso, Bresnahan and Beattie (BBB). Afterbehavioral assessment, the spinal cord was examined by a histologist for spinal tissuesparing.Results: From weeks 6-8, the functional recovery of the FOM rats significantly increasedin comparison to the FRM, although a significant difference in tissue sparing was not apparent.From weeks, 2-8 the functional recovery of the FOM and FRM groups as well astissue sparing of the FOM group increased significantly compared to the control group.Conclusion: Thus, the FOM treatment may be effective to promote functional recoveryand partially preserving tissue sparing

The role of biodegradable engineered random polycaprolactone nanofiber scaffolds seeded with nestin-positive hair follicle stem cells for tissue engineering

Background: Tissue engineering is a new approach to reconstruction and/or regeneration of lost or damaged tissue. The purpose of this study was to fabricate the polycaprolactone (PCL) random nanofiber scaffold as well as evaluation of the cell viability, adhesion, and proliferation of rat nestin-positive hair follicle stem cells (HFSCs) in the graft material using electrospun PCL nanofiber scaffold in regeneration medicine. Materials and Methods: The bulge HFSCs was isolated from rat whiskers and cultivated in Dulbecco's modified Eagle's medium/F12. To evaluate the biological nature of the bulge stem cells, flow cytometry using nestin, CD34 and K15 antibodies was performed. Electrospinning was used for the production of PCL nanofiber scaffolds. Furthermore, scanning electron microscopy (SEM) for HFSCs attachment, infiltration, and morphology, 3-(4, 5-di-methylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay for cell viability and cytotoxicity, tensile strength of the scaffolds mesh, and histology analysis were used. Results: Flow cytometry showed that HFSCs were nestin and CD34 positive but K15 negative. The results of the MTT assay showed cell viability and cell proliferation of the HFSCs on PCL nanofiber scaffolds. SEM microscopy photographs indicated that HFSCs are attached and spread on PCL nanofiber scaffolds. Furthermore, tensile strength of the scaffolds mesh was measured. Conclusion: The results of this study revealed that modified PCL nanofiber scaffolds are suitable for HFSCs seeding, attachment, and proliferation. Furthermore, HFSCs are attached and proliferated on PCL nanofiber scaffolds