Comparison of allotransplantation of fresh and vitrified mouse ovaries to the testicular tissue under influence of the static magnetic field

Objective: The aim of this study was to investigate the effects of static magnetic field [SMF] during transplantation of the ovarian tissue into the testis

Materials and Methods: In this experimental study, ovaries of 6- to 8-week-old female Naval Medical Research Institute [NMRI] mice were randomly divided into four groups: i. Fresh ovaries were immediately transplanted into the testicular tissue [FOT group], ii. Fresh ovaries were exposed to the SMF for 10 minutes and then transplanted into the testicular tissue [FOT+group], iii. Vitrified-warmed ovaries were transplanted into the testicular tissue [VOT group], and iv. Vitrified-warmed ovaries were transplanted into the testicular tissue and the transplantation site was then exposed to the SMF for 10 minutes [VOT+group]

Results: The lowest percentages of morphologically dead primordial follicles and the highest percentages of morphologically intact primordial follicles were seen in the FOT+ group [4.11% +/- 2.88 and 41.26% +/- 0.54, respectively]. Although the lowest significant percentage of maturation, embryonic development and fertility was observed in the VOT group as compared to the other groups, the difference in the fertility rate was not significant between the VOT and VOT+groups. Estrogen and progesterone concentrations were significantly higher in the FOT+group than those of the control mice

Conclusion: It is concluded that, exposure of the vitrified-warmed ovaries to SMF retains the structure of the graft similar to that of fresh ovaries

Effects of crocin supplementation during in vitro maturation of mouse oocytes on giutathione synthesis and cytoplasmic maturation

Background: Crocin is an active ingredient of saffron [Crocus sativus L] and its an-tioxidant properties have been previously investigated. This carotenoid scavenges free radicals and stimulates glutathione [GSH] synthesis; consequently, it may protect cells against oxidative stress. The aim of this research is to protect oocytes from oxidative stress by the addition of a natural source antioxidant

Materials and Methods: In the present in vitro experimental study, we collected cumulus oocyte complexes [COCs] from mouse ovaries of euthanized, 6-8 week-old female Naval Medical Research Institute [NMRI] mice. Oocytes were subjected to in vitro maturation [IVM] in the presence of either crocin [5 or 10 microg/ml], 5 mM buthionine-[S-R]-sulfoximine [BSO], or the combination of crocin plus BSO. Oocytes that matured in vitro in a medium without crocin or BSO supplements were considered as controls. Following 16-18 hours of IVM, matured oocytes [n=631] were fertilized by capacitated sperm from NMRI male mice, and cultured in vitro for up to 96 hours to assess preimplantation embryonic development. The levels of GSH in metaphase II [Mil] oocytes after IVM [n=240] were also assessed by the 5, 5-dithio-bis [2-nitrobenzoic acid] [DTNB]-GSH reductase recycling assay

Results: Supplementation of IVM media with 10 microg/ml crocin significantly [P<0.05] increased nuclear maturation, preimplantation development and GSH concentrations compared with the control group. Maturation of oocytes in IVM medium supplemented with BSO alone or the combination of microg/ml crocin and BSO drastically decreased GSH concentrations and subsequently resulted in low rates of maturation, fertilization and blastocyst development. However, the combination of 10 microg/ml crocin with 5 mM BSO increased the level of nuclear maturation which was comparable to the control group

Conclusion: Supplementation of IVM media with crocin can improve nuclear maturation rates and subsequent developmental potential of mouse oocytes. This may occur by its beneficial effect in increasing GSH concentrations in Mil oocytes

Follicle development of xenotransplanted sheep ovarian tissue into male and female immunodeficient rats

This study aimed to assess follicle survival after xenotransplantation of sheep ovarian tissue into male and female immunodeficient rats. We evaluated the effects of gonadotropin treatment on follicular development in the transplanted tissue. In this experimental study, sheep ovarian cortical strips were transplanted into the neck back muscles of 8 male and 8 female immunodeficient, castrated rats. Fourteen days after surgery, each rat was treated with human menopausal gonadotropin [hMG] for 9 weeks. One day after the last injection, ovarian tissues were removed and fixed for histology assessment. Histology analyses were performed before and after grafting. Estradiol [E[2]] levels were measured before and after gonadectomy, and at the end of the experiment. The control group consisted of 7 male and 7 female non-castrated/non-grafted rats and the sham group comprised 7 male and 7 female castrated/ non-grafted rats for comparison of serum E2 concentrations. The percentage of primordial follicles decreased after transplantation in male [25.97%] and female [24.14%] rats compared to the control group [ovarian tissue non-grafted; 37.51%]. Preantral follicles increased in the male [19.5%] and female [19.49%] transplanted rats compared to the control group [11.4%]. Differences in antral follicles between male [0.06 +/- 0.0%] and female [0.06 +/- 0.0%] rats were not noticeable compared to control [1.25 +/- 0.0%] rats. We observed a significantly higher percent of mean E[2] secretion in grafted males compared to grafted females [P<0.05]. Despite significant differences in E[2] secretion between xenografted male and female rats, we observed no statistical differences in terms of follicular development

Effects of saffron [crocus sativus L.] aqueous extract on in vitro maturation, fertilization and embryo development of mouse oocytes

Lower pregnancy rates of in vitro matured oocytes compared to those of in vivo stimulated cycles indicate that optimization of in vitro maturation [IVM] remains a challenge. Reduced developmental competence of in vitro matured oocytes shows that current culture systems for oocyte maturation do not adequately support nuclear and/or cytoplasmic maturation. Therefore this study evaluates the effects of different concentrations of saffron [Crocus sativus L.] aqueous extract [SAE], as an antioxidant agent on IVM of immature mouse oocytes. In this experimental study ,cumulus-oocyte complexes [COCs] were collected from 6-8 weeks old novel medical research institute [NMRI] female mice ovaries. COCs were cultured in IVM medium supplemented with 0 [control], 5, 10, 20 and 40 micro g/ml of SAE in 5% CO[2] at 37[degree sign] C. The rates of maturation, fertilization and development were recorded. ANOVA and Duncan's protected least significant test, using the SAS program was applied for all statistical analysis. The maturation rate was significantly higher in all groups treated with different concentrations of SAE compared with the control group [p<0.05]. However, the lower concentrations of SAE [10 and 5 micro g/ml] in maturation medium respectively increased the fertilization rate of oocytes and in vitro developmental competence when compared with the control group [p<0.05]. The results of this study indicate that lower concentrations of SAE are more appropriate to be added to maturation medium when compared with other experimental and control groups. Generally, we conclude that addition of appropriate amounts of natural extracts such as SAE to maturation medium improves oocyte maturation and embryo development