5-Fluorouracil disrupts ovarian preantral follicles in young C57BL6J mice.

PURPOSE: 5-Fluorouracil (5-FU), an anti-cancer drug, has been used for hepatoblastoma (HB) chemotherapy in children, who may have impaired  ovarian follicle pool reserve with lasting effects to reproduction. Therefore, this study aimed to investigate 5-FU effects on survival, growth, and morphology of ovarian preantral follicles from C57BL6J young mice. METHODS: Experiments were carried-out both in vivo and in vitro. Mice were treated with 5-FU injection (450 mg/kg i.p) or saline and sacrificed 3 days after to obtain ovaries for histology and molecular biology. Ovaries for in vitro studies were obtained from unchallenged mice and cultured under basic culture medium (BCM) or BCM plus 5-FU (9.2, 46.1, 92.2 mM). Preantral follicles were classified according to developmental stages, and as normal or degenerated. To assess cell viability, caspase-3 immunostaining was performed. Transcriptional levels for apoptosis (Bax, Bcl2, p53, Bax/Bcl2) and Wnt pathway genes (Wnt2 and Wnt4) were also analyzed. Ultrastructural analyses were carried-out on non-cultured ovaries. In addition, ß-catenin immunofluorescence was assessed in mouse ovaries. RESULTS: The percentage of all-types normal follicles was significantly lower after 5-FU challenge. A total loss of secondary normal follicles was found in the 5-FU group. The highest 5-FU concentrations reduced the percentage of cultured normal primordial follicles. Large vacuoles were seen in granulosa cells and ooplasm of preantral follicles by electron microscopy. A significantly higher gene expression for Bax and Bax/Bcl2 ratio was seen after 5-FU treatment. A marked reduction in ß-catenin immunolabeling was seen in 5-FU-challenged preantral follicles. In the in vitro experiments, apoptotic and Wnt gene transcriptions were significantly altered. CONCLUSION: Altogether, our findings suggest that 5-FU can deleteriously affect the ovarian follicle reserve by reducing preantral follicles survival.

In vitro long-term culture of isolated ovine preantral follicles: Influence of ethanol on steroid production, oocyte meiotic resumption, and metabolomic profile.

Ethanol is used routinely to dilute cell culture media supplements with little or no water solubility. This study evaluates the effect of low concentration of ethanol on the follicular development, oocyte maturation, hormone production, gene expression, and metabolomics profile of spent culture medium after long-term culture of isolated ovine preantral follicles. For this, follicles were cultured for 18 days in α-Minimum Essential Medium+ alone (control treatment) or supplemented with 100 ng/mL recombinant bovine FSH (rbFSH treatment) or with 0.2%-v/v ethanol (ethanol treatment). Ethanol treatment increased the percentage of degenerated follicles and oocytes significantly, however, it showed the highest estradiol secretion. Also, the rate of meiosis resumption was higher in ethanol treatment than Control treatment. Ethanol treatment decreased the mRNA levels of B-cell lymphoma 2 (BCL2), BCL2 associated X, Aquaporin 3, Connexin 43, Inhibin Subunit Beta A, kit ligand, Heat Shock Protein (HSP A1A) significantly when compared to the Control treatment. However, mRNA levels of cytochrome P450 family 19, and FSH receptors were significantly higher in ethanol treatment than in the Control treatment. The levels of some metabolites, which are likely amino acids, lipids, an analog of Cyclic guanosine monophosphate, and a derivative of phosphoinositol phosphate metabolism, had higher relative concentrations in ethanol and rbFSH treatments than the Control treatment. In conclusion, ethanol addition augmented the follicular and oocyte degeneration rates but increased the estradiol production and the meiotic resumption. Furthermore, the follicular metabolomic profile was similar between ethanol and rbFSH treatments being both treatments; however, different from the Control treatment.

Immunolocalization for glucocorticoid receptor and effect of cortisol on in vitro development of preantral follicles.

The aim of this study was to evaluate the immunolocalization for glucocorticoid receptor (NR3C1) in goat ovarian follicles and the effect of cortisol on in vitro development of preantral follicles. Goat ovarian fragments were cultured for 7 days under different cortisol concentrations (0, 1, 5 and 10 ng/ml). Before and after culture, the protein expression of NR3C1 was analyzed in ovarian tissue by immunohistochemical analysis. Moreover, the endpoints follicular morphology, viability, activation as well as follicular and oocyte diameter were also analyzed. The NR3C1 was strongly expressed in oocytes of primordial and antral follicles. A progressive increase of immunostaining for NR3C1 in granulosa cells from primordial to antral follicles was observed regardless of the treatment. After in vitro culture, it was observed a significant reduction in the rate of normal preantral follicles rate in the 10 ng/ml cortisol treatment when compared to the other treatments. Moreover, follicular and oocyte diameter significantly decreased in all treatments (cortisol 0, 1, 5 and 10 ng/ml) compared to the fresh control. After culture, the activation rate significantly increased when the follicles were exposed to 1, 5 and 10 ng/ml cortisol compared to the fresh control. In conclusion, it was observed the presence of NR3C1 in the oocyte and granulosa cells in all follicular categories, except in granulosa cells of primordial follicles. The in vitro culture showed that high cortisol concentration (10 ng/ml) exerts a deleterious effect on follicular survival.

In vitro growth and development of isolated secondary follicles from vitrified caprine ovarian cortex.

The aim of this study was to evaluate the viability, antrum formation and in vitro development of isolated secondary follicles from vitrified caprine ovarian cortex in a medium previously established for fresh isolated secondary follicles, in the absence (α-minimum essential medium (α-MEM+) alone) or presence of FSH and vascular endothelial growth factor (VEGF; α-MEM++FSH+VEGF). Ovarian fragments were distributed among five treatments (T1 to T5): fresh follicles were fixed immediately (T1), follicles from fresh tissue were cultured in vitro in α-MEM+ (T2) or α-MEM++FSH+VEGF (T3) and follicles from vitrified tissue were cultured in vitro in α-MEM+ (T4) or α-MEM++FSH+VEGF (T5). After 6 days of culture, treated follicles (T2, T3, T4 and T5) were evaluated for morphology, viability and follicular development (growth, antrum formation and proliferation of granulosa cells by Ki67 and argyrophilic nucleolar organiser region (AgNOR) staining). The levels of reactive oxygen species (ROS) in the culture media were also assessed. Overall, morphology of vitrified follicles was altered (P<0.05) compared with the fresh follicles. Follicular viability, antrum formation and ROS were similar between treatments (P>0.05). The average overall and daily follicular growth was highest (P<0.05) in T3. Granulosa cells in all treatments (T1, T2, T3, T4 and T5) stained positive for Ki67. However, fresh follicles from T3 had significantly higher AgNOR staining (P<0.05) compared with follicles of T1, T2, T4 and T5. In conclusion, secondary follicles can be isolated from vitrified and warmed ovarian cortex and survive and form an antrum when growing in an in vitro culture for 6 days.

High diluted and dynamised follicle stimulating hormone modulates steroid production in isolated porcine preantral follicles cultured in vitro.

OBJECTIVE: This study investigated the effect of two different follicle stimulating hormone (FSH) preparations (diluted/dynamised and diluted) on the in vitro development and steroid production (estradiol, progesterone and testosterone) of isolated porcine preantral follicle after in vitro culture. METHODS: Secondary follicles were cultured in Alpha Minimum Essential Medium (α-MEM+) supplemented with grain ethanol (AL - 0.2%, v/v), diluted/dynamised FSH (rFSH 6cH - 0.05 fg/mL) or diluted-only FSH (1.5 ng/mL) for 4 days. Follicle development was evaluated on the basis of follicular growth, morphology and hormone production. RESULTS: The percentage of follicular integrity and extrusion were not affected by the treatments after culture. For all treatments, follicular diameter increased significantly from Day 0 to Day 4. On Day 2 of culture, the estradiol production was significantly higher in AL and diluted-only FSH treatments compared with diluted/dynamised FSH. However, diluted/dynamised FSH showed a significantly higher progesterone production on Day 2. Only on Day 4, the testosterone production was higher in the AL than diluted-only FSH treatments, but similar to diluted/dynamised FSH treatment. Except for diluted/dynamised FSH treatment, progesterone production increased (P < 0.05) from Day 2 to Day 4; only for AL treatment, a significant increase of testosterone production was observed during culture. CONCLUSION: Compared to control the diluted/dynamised FSH addition increased progesterone production but decreased the estradiol production after in vitro culture of isolated porcine preantral follicles. Taken together the results suggest that at least for progesterone production the mechanism of action of diluted/dynamised FSH differs from its vehicle.

Unexpected effect of the vehicle (grain ethanol) of homeopathic FSH on the in vitro survival and development of isolated ovine preantral follicles.

The aims of this study were to investigate the effects of medium replacement system (experiment I) and of FSH presentations (homeopathic - FSH 6cH and allopathic FSH - rFSH; experiment II) on the in vitro development, hormone production and gene expression of isolated ovine preantral follicles cultured for 6 days. In experiment I, secondary follicles were cultured in the α-MEM+ supplemented with FSH 6cH (0.05 fg/ml) or recombinant bovine FSH (100 ng/ml) without/with daily medium addition. The homeopathic FSH treatments with/without medium addition improved (p < .05) follicular development compared to rFSH100 treatment without addition. FSH 6cH with addition showed the highest (p < .05) estradiol production. To verify whether the effects of homeopathic FSH were not due to its vehicle, experiment II was performed. The α-MEM+ was supplemented or not with alcohol (0.2% grain ethanol, v/v), FSH 6cH or rFSH100 with daily medium addition. Surprisingly, we found that all treatments improved follicular development compared to the α-MEM+ (p < .05). Moreover, homeopathic FSH was similar to the other treatments including its vehicle. In conclusion, its vehicle (ethanol) causes the effect of homeopathic FSH on in vitro development of isolated ovine preantral follicles.

The effects of insulin and follicle-simulating hormone (FSH) during in vitro development of ovarian goat preantral follicles and the relative mRNA expression for insulin and FSH receptors and cytochrome P450 aromatase in cultured follicles.

The actions of different concentrations of insulin alone or in combination with follicle-stimulating hormone (FSH) were evaluated by in vitro follicular development and mRNA expression of cytochrome P450 aromatase (CYP19A1) and as receptors for insulin (INSR) and FSH (FSHR) from isolated, cultured goat preantral follicles. Goat preantral follicles were microdissected and cultured for 18 days in the absence or presence of insulin (5 and 10 ng/ml or 10 µg/ml) alone or in combination with FSH. After 18 days, the addition of the maximum concentration of insulin to the culture medium reduced follicular survival and antrum formation rates significantly compared to the other treatments. However, when FSH was added to the culture medium, no differences between these two parameters were observed. Preantral and antral follicles from the fresh control as well as from all cultured follicles still presented a normal ultrastructural pattern. In medium supplemented with FSH, only insulin at 10 ng/ml presented oocytes with higher rates of meiosis resumption compared to control, as well as oocytes in metaphase II. Treatment with insulin (10 ng/ml) plus FSH resulted in significantly increased levels of INSR and CYP19A1 mRNA compared to that with other treatments. In conclusion, 10 ng/ml insulin associated with FSH was more efficient in promoting resumption of oocyte meiosis, maintaining survival, stimulating follicular development, and increasing expression of the INSR and CYP19A1 genes in goat preantral follicles.

Progesterone and Follicle Stimulating Hormone interact and promote goat preantral follicles survival and development in vitro / Progesterona e Hormônio Folículo-Estimulante interagem e promovem a sobrevivência e o desenvolvimento in vitro de folículos pré-antrais caprinos

We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) alone or containing progesterone (1, 2.5, 5, 10 or 20ng/mL), FSH (50ng/mL) or the interaction between progesterone and FSH. Fresh (non-cultured control) and cultured ovarian tissues were processed for histological and ultrastructural studies. After 7 days the addition of FSH to all progesterone concentrations maintained the percentage of normal follicles similar to fresh control. At day 7 of culture, a higher percentage of developing follicles was observed only in 2.5ng/ml of progesterone associated with FSH or 10ng/ml of progesterone alone when compared with control. From day 1 to day 7 of culture, a significant increase in the percentage of developing follicles was observed in MEM and 2.5ng/ml of progesterone + FSH. In addition, after 7 days, in all treatments, there was a significant increase in follicular diameter when compared with control, except for MEM alone and in 5ng/ml of progesterone + FSH or 10ng/ml of progesterone alone. Ultrastructural studies confirmed follicular integrity after 7 days of culture in 2.5ng/ml of progesterone with FSH. In conclusion, this study demonstrated that the interaction between progesterone and FSH maintains ultrastructural integrity, stimulates primordial follicles activation and further growth of cultured caprine preantral follicles.

Este trabalho verificou os efeitos da progesterona e do hormônio folículo-estimulante (FSH) na sobrevivência e no crescimento de folículos pré-antrais caprinos. Fragmentos de tecido ovariano foram cultivados por 1 ou 7 dias em Meio Essencial Mínimo (MEM) sozinho ou contendo progesterona (1, 2.5, 5, 10 ou 20ng/mL), FSH (50ng/mL) ou a combinação entre esses dois hormônios. O tecido fresco (controle não-cultivado) e o cultivado foram processados para análise histológica e ultra-estrutural. Após 7 dias a adição de FSH a todas as concentrações de progesterone manteve o percentual de folículos normais similar ao controle fresco. No dia 7 de cultivo, um alto percentual de folículos em desenvolvimento foi observado somente no tratamento com 2,5ng/ml de progesterona associada ao FSH ou com 10ng/ml de progesterona sozinha, em relação ao controle fresco. Do dia 1 para o dia 7 de cultivo, um aumento significativo no percentual de folículos em desenvolvimento foi observado no MEM sozinho e adicionado de 2,5ng/ml de progesterona + FSH. Além disso, após 7 dias, em todos os tratamentos, houve um aumento significativo no diâmetro folicular em relação ao controle, exceto nos tratamentos com MEM sozinho, 5ng/ml de progesterona + FSH ou 10ng/ml de progesterona sozinha. A análise ultra-estrutural confirmou a integridade follicular após 7 dias de cultivo no tratamento com 2,5ng/ml de progesterona + FSH. Em conclusão, este estudo demonstrou que a interação entre progesterona e FSH mantém a integridade ultra-estrutural, estimula a ativação de folículos primordiais e o posterior crescimento de folículos pré-antrais caprinos cultivados in vitro.

Catalase prevents lipid peroxidation and enhances survival of caprine preantral follicles cryopreserved in a 1,2-propanediol-freezing medium.

The objectives of this study were to determine: 1) the optimal concentration (1.0 or 1.5 M) and duration of exposure (5, 10, or 20 min) of ovarian tissue to 1,2-propanediol (PROH) on morphology and viability of caprine preantral follicles; and 2) the effect of supplementing cryopreservation medium supplementation with Trolox(®) (0.1, 0.5, or 1.0 mM) or catalase (5, 10, or 20 IU/mL) on follicular morphology, viability, and lipid peroxidation. Cryopreservation decreased (p<0.05) percentages of normal follicles relative to the control (84%). Although supplementation of the cryopreservation medium (1.0 M PROH) with catalase (10 or 20 IU/mL) or Trolox(®) (0.1 mM) resulted in follicular morphology and viability similar to that in the controls (P>0.05), lipid peroxidation was reduced only when 20 IU/mL catalase was added to the cryopreservation medium.

Anthelmintic activity of Jatropha curcas L. seeds on Haemonchus contortus.

The aim of this study was to evaluate the anthelmintic activity of hexane (HE), ethyl acetate (EA) and ethanol (EE) extracts obtained from the seeds of Jatropha curcas using the egg hatch inhibition assay (EHA) and the artificial larval exsheathment inhibition assay (LEIA). For the egg hatch assay, HE, EA and EE were used in concentrations of 3.12, 6.25, 12.5, 25 and 50 mg ml(-1), accompanied by a negative control (5% Tween 80) and a positive control (0.025 g ml(-1) thiabendazole). In LEIA, the extracts were tested at a concentration of 1000 µg ml(-1), accompanied by a negative control (PBS). To evaluate the effect of tannins, the extract with the greatest effect was incubated with polyvinyl polypyrrolidone (PVPP). The EE (50 mg ml(-1)) inhibited 99.8% of egg hatching. After the addition of PVPP, the ovicidal effectiveness of EE was reduced to 91.9%. Using the HE and EA, inhibition of egg hatching was 15.3% and 32.2%, respectively. In the LEIA, 18.9% of L3 incubated with EE were exsheathed (p<0.01). The addition of PVPP to EE reversed the inhibitory effect on larval exsheathment. The percentage of exsheathment of L3 incubated with HE (99.6%) and EA (97.8%) did not differ from the control group (p>0.05). The results show that the effects of EE on eggs are not solely due to the tannins. However, these secondary metabolites are implicated in blocking the larval exsheathment.

Steady-state level of epidermal growth factor (EGF) mRNA and effect of EGF on in vitro culture of caprine preantral follicles.

Our aim was to verify the steady-state level of epidermal growth factor (EGF) mRNA in goat follicles at various developmental stages and to investigate the influence of EGF on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify EGF mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of EGF and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for EGF and FSH receptor (FSH-R) was determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. EGF mRNA levels in secondary follicles were significantly higher than those in primordial follicles, whereas in small and large antral follicles, EGF mRNA levels in cumulus-oocyte complexes (COCs) were significantly higher than in granulosa/theca cells. During culture, EGF in the presence or absence of FSH increased the follicular daily growth rate of secondary follicles when compared with that in enriched alpha minimal essential medium. FSH, EGF or both reduced EGF mRNA levels, whereas EGF reduced FSH-R mRNA levels after follicle culture for 6 days. Thus, EGF mRNA levels are higher in secondary follicles than in earlier stages, with both FSH and EGF promoting the growth of goat secondary follicles. EGF and/or FSH reduce EGF mRNA levels, whereas EGF decreases FSH-R mRNA levels, in cultured secondary follicles.

Steady-state level of kit ligand mRNA in goat ovaries and the role of kit ligand in preantral follicle survival and growth in vitro.

The aims of this study were to investigate steady-state level of Kit Ligand (KL) mRNA and its effects on in vitro survival and growth of caprine preantral follicles. RT-PCR was used to analyze caprine steady-state level of KL mRNA in primordial, primary, and secondary follicles, and in small (1-3 mm) and large (3-6 mm) antral follicles. Furthermore, ovarian fragments were cultured for 1 or 7 days in Minimal Essential Medium (MEM(+)) supplemented with KL (0, 1, 10, 50, 100, or 200 ng/ml). Noncultured (control) and cultured fragments were processed for histology and transmission electron microscopy (TEM). RT-PCR demonstrated an increase in steady-state level of KL mRNA during the transition from primary to secondary follicles. Small antral follicles had higher steady-state levels of KL mRNA in granulosa and theca cells than large follicles. After 7 days, only 50 ng/ml of KL had maintained the percentage of normal follicles similar to control. After 1 day, all KL concentrations reduced the percentage of primordial follicles and increased the percentage of growing follicles. KL at 10, 50, 100, or 200 ng/ml increased primary follicles, compared to MEM(+) after 7 days. An increase in oocyte and follicular diameter was observed at 50 ng/ml of KL. TEM confirmed ultrastructural integrity of follicles after 7 days at 50 ng/ml of KL. In conclusion, the KL mRNAs were detected in all follicular categories. Furthermore, 50 ng/ml of KL maintained the integrity of caprine preantral follicle cultured for 7 days and stimulated primordial follicle activation and follicle growth.

Combination of chemical analyses and animal feeding trials as reliable procedures to assess the safety of heat processed soybean seeds.

This study assessed whether chemical analyses are sufficient to guarantee the safety of heat processing of soybeans (SB) for human/animal consumption. The effects of extrusion and dry-toasting were analyzed upon seed composition and performance of broiler chicks. None of these induced appreciable changes in protein content and amino acid composition. Conversely, toasting reduced all antinutritional proteins by over 85%. Despite that, the animals fed on toasted SB demonstrated a low performance (feed efficiency 57.8 g/100 g). Extrusion gave place to higher contents of antinutrients, particularly of trypsin inhibitors (27.53 g/kg flour), but animal performance was significantly (p < 0.05) better (feed efficiency 63.2 g/100 g). Upon the basis of chemical analyses, dry-toasting represents the treatment of choice. However, considering the results of the feeding trials, extrusion appears to be the safest method. In conclusion, in order to evaluate the reliability of any processing method intended to improve nutritional value, the combination of chemical and animal studies is necessary.

Dimethyl sulfoxide perfusion in caprine ovarian tissue and its relationship with follicular viability after cryopreservation.

Ovarian cortical fragments (3 x 3 x 1 mm) were exposed to dimethyl sulfoxide (DMSO) in different concentrations for further analysis of cryoprotectant perfusion by applying high-performance liquid chromatography (HPLC) and conventional cryopreservation. This simple perfusion test can predict the efficiency of the cryopreservation procedure.

Quantification of dimethyl sulfoxide perfusion in sheep ovarian tissue: a predictive parameter for follicular survival to cryopreservation.

The aim of the present study was to determine the amount of dimethyl sulfoxide (DMSO) present in sheep ovarian tissue after exposure to cryoprotectant at different times (5, 10, 20, or 30 min) and at different concentrations (1.0, 1.5, or 2.0 M). To quantify the levels of DMSO in the ovarian tissue, the high-performance liquid chromatography (HPLC) method was applied. In addition, viability of preantral follicles after toxicity test and cryopreservation of ovarian tissue using the above mentioned concentrations of DMSO and exposure times was evaluated. We have observed that the presence of ∼0.6 mg of DMSO into the ovarian tissue may be deleterious to the sheep preantral follicles. In addition, the application of a short exposure time (5 min at 1.5 or 2.0 M DMSO) or low concentration (1.0 M for 10 min) of DMSO successfully preserves sheep preantral follicles following cryopreservation.