Does the presence of AGG interruptions within the CGG repeat tract have a protective effect on the fertility phenotype of female FMR1 premutation carriers?

PURPOSE: While FMR1 premutation carriers (CGG 55-200) were shown to have reduced success with IVF treatment (lower oocyte yield), studies reporting on the association between the number of CGG repeats and patients' response to controlled ovarian hyperstimulation (COH) are inconsistent. In the present study, we aim to explore whether the number of CGG repeats in women with premutation in FMR1 gene, undergoing COH for IVF, correlates with COH variables and whether the number of AGG interruptions may function as a "protective factor" by improving the ovarian response to COH. METHODS: Retrospective study, in an academic IVF-PGD unit. Fifty-seven consecutive FMR1 premutation carriers who underwent 285 IVF treatment cycles were included. The numbers of CGG repeats and AGG interruptions were retrieved and correlated to the demographics and COH variables. RESULTS: There were no significant association between the numbers of CGG or the AGG interruptions and the number of oocyte retrieved or the peak estradiol levels. The lack of association was also observed when including all the IVF treatment cycles or only the first or last IVF treatment cycle. Moreover, no associations were found between the number of CGG repeats or AGG interruptions and other COH variables, i.e., duration of stimulation, the total dose of gonadotropin used, or the number of top-quality embryos. CONCLUSIONS: No associations were observed between the number of CGG repeats or AGG interruptions and any of the COH variables. Further studies are required to identify early biomarkers of POI to empower FMR1 premutation carriers with risk assessment tools to consider procedures such as fertility preservation.

FMRpolyG accumulates in FMR1 premutation granulosa cells.

BACKGROUND: Fragile X premutation (Amplification of CGG number 55-200) is associated with increased risk for fragile X-Associated Premature Ovarian Insufficiency (FXPOI) in females and fragile X-associated tremor/ataxia syndrome (FXTAS) predominantly in males. Recently, it has been shown that CGG repeats trigger repeat associated non-AUG initiated translation (RAN) of a cryptic polyglycine-containing protein, FMRpolyG. This protein accumulates in ubiquitin-positive inclusions in neuronal brain cells of FXTAS patients and may lead to protein-mediated neurodegeneration. FMRpolyG inclusions were also found in ovary stromal cells of a FXPOI patient. The role of FMRpolyG expression has not been thoroughly examined in folliculogenesis related cells. The main goal of this study is to evaluate whether FMRpolyG accumulates in mural granulosa cells of FMR1 premutation carriers. Following FMRpolyG detection, we aim to examine premutation transfected COV434 as a suitable model used to identify RAN translation functions in FXPOI pathogenesis. RESULTS: FMRpolyG and ubiquitin immunostained mural granulosa cells from six FMR1 premutation carriers demonstrated FMRpolyG aggregates. However, co-localization of FMRpolyG and ubiquitin appeared to vary within the FMR1 premutation carriers' group as three exhibited partial ubiquitin and FMRpolyG double staining and three premutation carriers demonstrated FMRpolyG single staining. None of the granulosa cells from the five control women expressed FMRpolyG. Additionally, human ovarian granulosa tumor, COV434, were transfected with two plasmids; both expressing 99CGG repeats but only one enables FMRpolyG expression. Like in granulosa cells from FMR1 premutation carriers, FMRpolyG aggregates were found only in COV434 transfected with expended CGG repeats and the ability to express FMRpolyG. CONCLUSIONS: Corresponding with previous studies in FXTAS, we demonstrated accumulation of FMRpolyG in mural granulosa cells of FMR1 premutation carriers. We also suggest that following further investigation, the premutation transfected COV434 might be an appropriate model for RAN translation studies. Detecting FMRpolyG accumulation in folliculogenesis related cells supports previous observations and imply a possible common protein-mediated toxic mechanism for both FXPOI and FXTAS.

Combination of ovarian tissue harvesting and immature oocyte collection for fertility preservation increases preservation yield.

The aim of this study was to evaluate the safety and efficacy of combined ovarian tissue cryopreservation and oocyte aspiration just before ovarian tissue cryobanking. A retrospective cohort study of fertility preservation patients treated in 2007-2013 in one tertiary centre was performed. A total of 255 cancer patients were admitted for fertility preservation: 142 patients underwent ovarian tissue cryopreservation only (OTC), 56 underwent OTC plus oocyte retrieval from ovarian tissue (OTIVM), nine underwent oocyte aspiration and in-vitro maturation (AIVM) and 48 underwent all three procedures. The total number of oocytes, total number of metaphase II (MII) oocytes, maturation rate, fertilization rate and total number of cryopreserved oocytes between groups were compared. The study found significantly more oocytes (P < 0.001), more MII oocytes (P < 0.001), better maturation rate (P < 0.01) and more cryopreserved oocytes (P < 0.05) with all three compared with OTIVM or OTC. No adverse outcome was observed by performing oocyte retrieval before ovarian resection for cryopreservation. In conclusion, oocyte aspiration just before ovarian tissue cryobanking is safe and gains more oocytes with a better maturation rate than ovarian tissue oocyte cryobanking alone. Better results were obtained with 3 days of stimulation before oocyte retrieval.

IVF for fertility preservation in breast cancer patients--efficacy and safety issues.

BACKGROUND: Potential risks on future fertility have become a dominant issue in consultation and management of newly diagnosed young cancer patients. Several fertility preservation strategies are currently available. Of those, ovarian stimulation followed by IVF and embryo cryopreservation is the most established one and is especially applicable in reproductive aged breast cancer patients. AIM: The aim of this study is to provide a comprehensive review on ovarian stimulation and IVF for fertility preservation in newly diagnosed breast cancer patients. METHODS: Review of relevant literature is available through PubMed and Google scholar. RESULTS: The use of IVF for fertility preservation in breast cancer patients raises dilemmas regarding efficacy and safety of controlled ovarian stimulation. Among these are the suggested role of malignancy and BRCA mutation in reducing ovarian response to stimulation, strategies designated to protect against hyper-estrogenic state associated with stimulation (co-treatment with tamoxifen or letrozole), and possible adjustments to accommodate oncologic-related time constraints. CONCLUSION: Ovarian stimulation followed by IVF forms an important fertility preservation strategy for newly diagnosed young breast cancer patients, though live born rates following thawed embryo transfer in these patients are still lacking. Recent advances in controlled ovarian stimulation protocols provide practical options for some of the challenges that breast cancer patients present.

Cortical fibrosis and blood-vessels damage in human ovaries exposed to chemotherapy. Potential mechanisms of ovarian injury.

BACKGROUND: Chemotherapy destroys primordial follicles and can lead to ovarian atrophy. Although reports indicate that apoptosis is the mechanism responsible for follicle loss, additional pathways can be involved. This study investigates the damage in human ovaries after administration of non-sterilizing doses of chemotherapy. METHODS: In a blind study, pathological changes in ovarian tissue harvested for cryopreservation were evaluated. The study group comprised young non-sterile cancer patients, previously exposed to chemotherapy who were (mean +/- SD), when compared with non-exposed patients. RESULTS: Thirty-five cancer patients aged 28.7 +/- 6.74; 17 were previously exposed to non-sterilizing chemotherapy and 18 were not. In all samples, primordial follicles were present. In previously exposed patients, damage to cortical blood vessel and proliferation of small vessels was observed. The cortex showed focal areas of fibrosis with disappearance of follicles (sensitivity 76%, positive predictive value 75% for <37 years old patients). Older patients, not exposed to chemotherapy (5/7) showed similar pathological changes. CONCLUSIONS: Injury to blood vessels and focal ovarian cortical fibrosis are aspects of ovarian damage caused by chemotherapy. These findings indicate a potential additional mechanism of damage to the direct apoptotic effect of chemotherapy on follicles. The possibility that these changes are involved in ageing ovaries should be further investigated.

Resveratrol, a natural aryl hydrocarbon receptor antagonist, protects sperm from DNA damage and apoptosis caused by benzo(a)pyrene.

Benzo(a)pyrene (BaP), an aryl hydrocarbon receptor (AhR) ligand present in cigarette smoke and car exhaust, is thought to have negative effects on male reproduction. We hypothesized that BaP damages sperm through AhR activation, phase I enzyme induction, DNA adduct formation, and increased germ cell apoptosis in the testis, and that resveratrol, a natural competitive inhibitor of the AhR found in some red wines, could prevent the adverse effects of BaP on sperm. Male Balb C mice were injected subcutaneously (s.c.) for 5 weeks with a range of BaP doses (0.5 mg/kg to 50 mg/kg). Live sperm were obtained from the vas deferens, counted, and stained to measure annexin-V positive (apoptotic) cells. In a subsequent study, mice were injected for 5 weeks with corn oil (control), BaP (5 mg/kg/week), or BaP plus resveratrol (50 mg/kg/week) (n = 3 per group). Immunohistochemistry (IHC) was performed on testis sections for the determination of CYP1A1, BaP diol epoxide (BPDE) DNA adducts, and apoptosis and the results quantified by using the HSCORE, a semiquantitative scoring system. Our results demonstrated that sperm counts after 5 weeks were inversely correlated to BaP dosage. BaP (0.5 to 5 mg/week) positively correlated with sperm apoptosis while higher doses increased sperm necrosis. CYP1A1 protein was observed mainly in interstitial cells of some testis sections, but there was no significant induction by BaP. BPDE DNA adducts were induced in all components of the seminiferous tubules by BaP and suppressed by resveratrol: median HSCORE (interquartile range) control 61 (52-71.5); BaP 213 (192-248), P = 0.01 compared to control; BaP plus resveratrol 83 (70-90). BaP significantly increased apoptosis, mainly in spermatogonia: medain HSCORE (interquartile range) BaP 189 (161-223) versus control 83 (57-93), P < 0.01; and this effect was abrogated by resveratrol. Median HSCORE for BaP plus resveratrol was 112 (range 99-121). In summary, BaP caused increased sperm cell BPDE DNA adduct formation and apoptosis in the mouse. The natural AhR antagonist, resveratrol diminished BaP-induced DNA adducts and apoptosis in seminiferous tubules.