Metabolomic profile of seminal plasma from Guzerá bulls (Bos indicus) with contrasting sperm freezability phenotypes

The present study evaluated the seminal plasma metabolome of Bos indicus Guzerá bulls with good (n = 4) and poor (n = 5) sperm freezability. Animals were raised in natural pasture of a 'Caatinga' ecosystem, in the semi-arid region of Brazil. Seminal plasma samples were subjected to gas chromatography coupled to mass spectrometry and data, analysed using bioinformatics tools (Cytoscape with the MetScape plug-in). Sixty-two metabolites were identified in the bovine seminal plasma. Fatty acids and conjugates and organic compounds were the predominant seminal fluid metabolites, followed by carboxylic acids and derivatives, amino acids, benzenes and steroids and derivatives, carbohydrates and carbohydrate conjugates and prenol lipids. Multivariate analysis indicated a distinct separation of seminal plasma metabolomes from bulls with contrasting sperm freezability. Abundances of propanoic acid, d-ribose and glycine were greater in the seminal plasma of bulls with good sperm freezability. Heptadecanoic acid and undecanoic acid were the predominant in bulls of poor sperm freezability. Propanoic acid is an energy source for spermatozoa and may act as an antimicrobial component in semen. Glycine acts against oxidizing and denaturing reactions. d-ribose is also an energy source and reduces apoptosis and oxidative stress. Undecanoic acid may protect sperm against fungal damage. This study provides fundamental information approximately the seminal plasma metabolome of tropically adapted bulls and its association with sperm freezability. However, further studies with larger groups of animals are needed to validate those metabolites as markers of sperm freezability. This strategy could support the selection of sires with superior sperm cryoresistance.

Global proteomic analysis of pre-implantational ovine embryos produced in-vitro

The present study was conducted to characterize the major proteome of pre-implantation (D6) ovine embryos produced in vitro. COCs were aspirated from antral follicles (2-6 mm), matured and fertilized in vitro, and cultured until day six. Proteins were extracted separately from three pools of 45 embryos and separately run in SDS-PAGE. Proteins from each pool were individually subjected to in-gel digestion followed by LC-MS/MS. Three "raw. files" and protein lists were produced by Pattern Lab software but only proteins present in all three lists were used for the bioinformatics analyses. https://david.ncifcrf.govThere were 2,262 proteins identified in the 6-day old ovine embryos, including albumin, zona pellucida glycoprotein 2, 3 and 4, peptidyl arginine deiminase 6, actin cytoplasmic 1, gamma-actin 1, pyruvate kinase, heat shock protein 90 and protein disulfide isomerase, among others. Major biological processes linked to the sheep embryo proteome were translation, protein transport and protein stabilization, and molecular functions, defined as ATP binding, oxygen carrier activity and oxygen binding. There were 42 enriched functional clusters according to the 2,147 genes (UniProt database). Ten selected clusters with potential association with embryo development included translation, structural constituent of ribosomes, ribosomes, nucleosomes, structural constituent of the cytoskeleton, microtubule-based process, translation initiation factor activity, regulation of translational initiation, cell body and nucleotide biosynthetic process. The most representative KEEG pathways were ribosome, oxidative phosphorylation, glutathione metabolism, gap junction, mineral absorption, DNA replication and cGMP-PKG signaling pathway. Analyses of functional clusters clearly showed differences associated with the proteome of pre-implantation (D6) sheep embryos generated after in vitro fertilization in comparison with in vivo counterparts (Sanchez et al., 2021; https://doi.org/10.1111/rda.13897), confirming that the quality of in vitro derived blastocysts are unlike those produced in vivo. The present study portrays the first comprehensive overview of the proteome of pre-implantational ovine embryos grown in vitro.

Microbiological load and preantral follicle preservation using different systems for ovarian tissue vitrification in the red-rumped agouti

We evaluated the effect of open and closed systems used for ovarian tissue vitrification on the microbiological load and preservation of preantral follicles (PAFs) in the red-rumped agoutis. The ovaries from eight females were recovered and fragmented, with four cortexes fragments immediately fixed and evaluated (fresh group). The other fragments were processed for the solid-surface vitrification method (SSV) or an ovarian tissue cryosystem (OTC) using fetal calf serum, ethylene glycol, and sucrose as cryoprotectants, stored for two weeks, and rewarmed. Subsequently, fragments were subjected to a 24-h in vitro culture and assessed for microbiological load, PAF morphology, and DNA integrity. There was no fungal contamination; however, the vitrified samples from two individuals showed bacterial contamination of 79 200 colony forming units per milliliter (CFU)/mL for SSV and 3120 CFU/mL for OTC. From those samples, a total of eight different types of bacterial colonies were isolated and identified as coagulase-negative Staphylococci and Gram-positive bacilli. Regarding PAF morphology, both systems provided adequate preservation, with values higher than 70% normal follicles observed before and after culture. The TUNEL assay revealed that both SSV (52.39%) and OTC (41.67%) could preserve DNA integrity after vitrification and after 24 h of culture. In summary, both open and closed systems were equally efficient in preserving agouti ovarian tissues, especially concerning the preantral follicle morphology and DNA integrity; however, the OTC seems to provide a less adequate environment for bacterial proliferation.

Induced-damages on preantral follicles by withanolide D, a potent chemotherapy candidate are not attenuated by melatonin

Withanolide D (WD) has been investigated as an antineoplastic drug. This study aimed to evaluate whether melatonin (MT) could attenuate toxic effects on preantral follicles enclosed in the ovarian cortex (experiment 1 - E1) or on isolated secondary follicles (experiment 2 - E2) exposed to WD. For E1, ovarian cortex was incubated for 48 h to: (1) α-MEM⁺; (2) α-MEM⁺ plus 6 μM WD; (3) α-MEM⁺ plus 3 mmol/L MT or (4) α-MEM⁺ plus WD and MT. For E2, secondary follicles were exposed for until 96 h in. (1) only to basic medium (α-MEM⁺⁺/α-MEM⁺⁺); (2) α-MEM⁺⁺ plus 3 mmol/L MT (MT/MT); (3) α-MEM⁺⁺ until 48 h, followed by more 48 h in 6 μM WD (α-MEM⁺⁺/WD) or (4) a pre-exposure to MT for until 48 h, followed by more 48 h of exposure to WD plus MT (MT/MT + WD). The main results obtained showed that exposure to drugs caused damage to follicular morphology (WD or WD + MT) and diameter (WD) in the ovarian cortex or in isolated follicles. In pre-antral follicles in situ, ATM expression increased in the presence of WD, MT or association. As for the secondary follicles, ATM and γH2AX were immunostained in the granulosa and theca cells and oocytes in all treatments. TAp63α was immunostained in follicles included in the ovarian cortex and in isolated follicles. We conclude that melatonin did not provide protection and could have enhanced the toxic effect of WD to follicles surrounded or not by the ovarian cortex.

Response of preantral follicles exposed to quinoxaline: A new compound with anticancer potential

The culture of preantral follicles as an in vitro model to evaluate the toxicity of new anticancer drug has being established. Therefore, the aim of this study was to evaluate the effect of quinoxaline derivative the 2 2- (XYZC 6H 3 -CH=N-NH)-quinoxaline, 1 (QX) on caprine preantral follicles. We evaluate the follicular morphology and activation, proliferation and apoptosis of granulosa cells and finally the protein (ABCB1) and genes expression (cyclin/Cdks), respectively involved in multidrug resistance and cell cycle progression. Ovarian fragments containing primordial and developing follicles were exposed (in vitro culture) to different concentrations of QX (QX1.5, QX3.0 or QX6.0 μM/mL) during 6 days. To evaluate the effect of QX, the ovarian tissue was exposed to Paclitaxel 0.1 μg/mL (PTX - negative control) or in culture media without QX (MEM). At the end of exposure time, we realized that the QX (all concentrations) increased (P < .05) the normal morphology of preantral follicles compared to control (not treated ovarian tissue) or MEM. However, QX6.0 showed a enhanced (P < .05) on follicular activation (burnout) and apoptosis than QX1.5 and QX3.0. Expression of ABCB1 was similar between QX1.5 and QX6.0 and both were lower than control, MEM and PTX. Interestingly, the apoptosis rate in QX3.0 was similar to control and MEM and lower then QX1.5; QX6.0 and PTX. We conclude that quinoxaline may be a promising chemotherapeutic agent, however, other concentrations within a defined range (2-5.5 μM) could be widely investigated.

Early ovine preantral follicles have a potential to grow until antral stage in two-step culture system in the presence of aqueous extract of Justicia insularis

The objective of this study was to determine whether preantral follicles cultured in vitro for 7 days within ovine ovarian cortical strips could be isolated at the secondary follicles (SF) and grown until antral stage during an additional 6 days period of in vitro culture in the presence of aqueous extract of Justicia insularis. Fresh ovarian fragments from 16 adult sheep were fixed for histological analysis (Control 1) or in vitro cultured individually in α-MEM⁺ supplemented with 0.3 mg/ml J. insularis (Step 1) for 7 days. Part of the fragments then were fixed for histological analysis (in vitro culture group). Remaining fragments were exposed stepwise to increasing trehalose concentrations before immediate isolation of SF and viability assessment (Control 2) or after 6 days of culture in α-MEM⁺⁺ supplemented with 0.3 mg/ml J. insularis (Step 2). In Step 1, percentage of follicular activation was 80%. In Step 2, a significant increase (p < 0.05) in follicular diameter and antrum formation within 6 days in vitro culture of isolated follicles was achieved. The total antioxidant capacity from both steps significantly increase (p < 0.05) from day 2 to day 6. Confocal analysis of oocytes showed 57.14% oocytes with homogeneous distribution and 42.86% with peri-cortical distribution. In conclusion, SF can be successfully isolated from sheep ovarian cortex after 7 days of culture and are capable of surviving and forming an antral cavity if cultured in vitro for an additional 6 days in the presence of 0.3 mg/ml J. insularis.

Anethole reduces oxidative stress and improves in vitro survival and activation of primordial follicles

Primordial follicles, the main source of oocytes in the ovary, are essential for the maintenance of fertility throughout the reproductive lifespan. To the best of our knowledge, there are no reports describing the effect of anethole on this important ovarian follicle population. The aim of the study was to investigate the effect of different anethole concentrations on the in vitro culture of caprine preantral follicles enclosed in ovarian tissue. Randomized ovarian fragments were fixed immediately (non-cultured treatment) or distributed into five treatments: α-MEM⁺ (cultured control), α-MEM⁺ supplemented with ascorbic acid at 50 μg/mL (AA), and anethole at 30 (AN30), 300 (AN300), or 2000 µg/mL (AN2000), for 1 or 7 days. After 7 days of culture, a significantly higher percentage of morphologically normal follicles was observed when anethole at 2000 μg/mL was used. For both culture times, a greater percentage of growing follicles was observed with the AN30 treatment compared to AA and AN2000 treatments. Anethole at 30 and 2000 µg/mL concentrations at days 1 and 7 of culture resulted in significantly larger follicular diameter than in the cultured control treatment. Anethole at 30 µg/mL concentration at day 7 showed significantly greater oocyte diameter than the other treatments, except when compared to the AN2000 treatment. At day 7 of culture, levels of reactive oxygen species (ROS) were significantly lower in the AN30 treatment than the other treatments. In conclusion, supplementation of culture medium with anethole improves survival and early follicle development at different concentrations in the caprine species.

In situ cultured preantral follicles is a useful model to evaluate the effect of anticancer drugs on caprine folliculogenesis

Despite the increase in the incidence of cancer, the number of women who survive cancer treatment is growing. However, one of the principal results of chemotherapy is premature ovarian failure (POF). The aim of this study was to use the in situ culture preantral follicles as an in vitro model to evaluate the toxicity of two anticancer drugs, doxorubicin (DXR) and paclitaxel (PTX), on the integrity and development of ovarian follicles. Fragments of the ovarian cortex of goats were cultured in vitro for 1 or 7 days in α-MEM(+) supplemented with different concentrations of DXR (0.003, 0.03, or 0.3 µg/mL) and PTX (0.001, 0.01, or 0.1 µg/mL). Analyses were performed before and after culture to evaluate tissue integrity by classical histology, apoptosis by TUNEL assay, DNA laddering kit and the detection of activated caspase 3, and DNA damage by the immune detection of phosphorylated histone H2A.x (H2AXph139). Both DXR and PTX reduced the number of morphologically normal primordial and developing follicles. Positive staining for TUNEL and active caspase 3 was detected in all the samples (P < 0.05). Therefore, we propose the in situ culture of caprine preantral follicles as a useful experimental model for assessing the toxic effects of the chemotherapeutic agents on ovarian folliculogenesis. Microsc. Res. Tech. 79:773-781, 2016. © 2016 Wiley Periodicals, Inc.

Anethole improves the in vitro development of isolated caprine secondary follicles

The aim of this study was to investigate the effect of three concentrations of anethole (30, 300, and 2000 μg/mL) on survival, antrum formation, follicular diameter, and oocyte maturation in the caprine species. The study also evaluated the effects of anethole on transcripts of ICAM-1, CAV-1, TIMP-2, and PAI-1 genes and levels of reactive oxygen species (ROS) in isolated goat preantral ovarian follicles before and after in vitro culture for 18 days. Preantral follicles were isolated from goat ovaries and individually cultured in alpha minimum essential medium modified (α-MEM⁺), defined as the control treatment, α-MEM⁺ supplemented with ascorbic acid at a concentration of 100 μg/mL (AA), or α-MEM⁺ supplemented with three different concentrations of anethole (30, 300, 2000 μg/mL) for a period of 18 days. Treatments were named as α-MEM⁺, AA, AN30, AN300, and AN2000, respectively. After culture, the follicles were opened, the cumulus oocytes complex (COCs) were removed and matured in vitro. The walls of the follicles were used for the quantitation of mRNA by quantitative real-time polymerase chain reaction. Finally, the medium collected at the end of culture was used for the measurements of ROS. After 18 days of culture, the AA treatment showed the percentage of intact follicles and follicular diameter significantly higher compared with the other treatments. However, daily growth rate, antrum formation, and also oocyte diameter were similar among the treatments. In addition, compared with AA, the rate of oocytes for in vitro maturation (diameter ≥ 110 μm) and the meiosis resumption rate were significantly higher in the treatments AN30 and AN2000, respectively. When assessing gene related to remodeling of the basement membrane, significant differences in mRNA levels for ICAM-1, CAV-1, TIMP-2, and PAI-1 were observed in comparison with Day 0, i.e., in the noncultured control. In addition, the ROS from Day 12, all treatments with the addition of anethole have significantly lower values of ROS than α-MEM⁺ and AA. In conclusion, the addition of anethole to the in vitro culture medium was able to improve the development of goat preantral follicles by reducing concentrations of ROS and increasing the percentage of oocytes able to resume meiosis.

Balance of insulin and FSH concentrations improves the in vitro development of isolated goat preantral follicles in medium containing GH

The aim of this study was to evaluate the effect of different combinations of insulin and FSH concentrations in culture media containing GH on the in vitro follicle morphology, antrum formation, growth rates, estradiol (E2) production, oocyte viability and maturation as well as gene expression for FSHR, GHR, INSR, CYP19A1, CYP17, 3ßHSD. Secondary follicles were individually cultured for 18 days in a basic medium containing 50ng/mL GH supplemented with low insulin concentration (INS-LW: 10ng/mL) or high insulin concentration (INS-HG: 10μg/mL) alone or with a fixed FSH concentration (FSH100: 100ng/mL) or with increasing FSH concentrations (FSH-SEQ: 100ng/mL, days 0-6; 500ng/mL, days 6-12; 1000ng/mL days 12-18). In the INS-LW treatment was observed a higher (P<0.05) incidence of normal follicles at day 18 of culture. However, overall higher (P<0.05) follicular growth, oocyte diameter and meiotic resumption rates were obtained using INS-HG+FSH 100. The INS-HG and INS-HG+FSH100 treatments showed higher E2 production and mRNA levels for CYP19A1, CYP17, 3βHSD when compared to INS-LW and INS-LW+FSH100. However, the addition of increasing FSH concentration, regardless of insulin concentration, did not improve the follicular growth, meotic resumption, E2 production or gene expression of steroidogenic enzymes when compared with INS-HG+FSH100. In conclusion, in presence of GH, a basic medium supplemented with 10μg/mL insulin and 100μg/mL FSH throughout the culture period, improves follicular and oocyte growth, oocyte meiotic resumption and E2 production from isolated preantral caprine follicles cultured in vitro.