Embryo-fetal safety evaluation of ondansetron in rats

BACKGROUND

Ondansetron is a 5HT3 receptor antagonist, used to mitigate the effects of nausea and vomiting after chemotherapy or surgery. Since nausea and vomiting are common experiences during the first trimester of pregnancy, this antiemetic has been the main drug used during this period.

METHODS

To evaluate the effects of ondansetron on the embryo-fetal development, which are still very contradictory, pregnant rats were exposed to therapeutic doses of ondansetron (1.7 or 2.5 mg/kg) daily, from gestational day (GD) 6 to 15.

RESULTS

No clinical signs of toxicity were observed in dams during the treatment. Although the hemato-biochemical parameters were similar among the groups, histological changes, as well as a reduction in the weight of kidney were found in the treated dams. After fetal examination, no visceral and skeletal abnormalities were observed in treated fetuses.

CONCLUSION

In conclusion, therapeutic doses of ondansetron have low teratogenic potential in rats. These data provide important information about the drug safety during pregnancy.

Effect of Aphidicolin, a Reversible Inhibitor of Eukaryotic Nuclear DNA Replication, on the Production of Genetically Modified Porcine Embryos by CRISPR/Cas9

Mosaicism is the most important limitation for one-step gene editing in embryos by CRISPR/Cas9 because cuts and repairs sometimes take place after the first DNA replication of the zygote. To try to minimize the risk of mosaicism, in this study a reversible DNA replication inhibitor was used after the release of CRISPR/Cas9 in the cell. There is no previous information on the use of aphidicolin in porcine embryos, so the reversible inhibition of DNA replication and the effect on embryo development of different concentrations of this drug was first evaluated. The effect of incubation with aphidicolin was tested with CRISPR/Cas9 at different concentrations and different delivery methodologies. As a result, the reversible inhibition of DNA replication was observed, and it was concentration dependent. An optimal concentration of 0.5 μM was established and used for subsequent experiments. Following the use of this drug with CRISPR/Cas9, a halving of mosaicism was observed together with a detrimental effect on embryo development. In conclusion, the use of reversible inhibition of DNA replication offers a way to reduce mosaicism. Nevertheless, due to the reduction in embryo development, it would be necessary to reach a balance for its use to be feasible.

Serum supplementation during bovine embryo culture affects their development and proliferation through macroautophagy and endoplasmic reticulum stress regulation

Serum supplementation during bovine embryo culture has been demonstrated to promote cell proliferation and preimplantation embryo development. However, these desirable outcomes, have been associated with gene expression alterations of pathways involved in macroautophagy, growth, and development at the blastocyst stage, as well as with developmental anomalies such as fetal overgrowth and placental malformations. In order to start dissecting the molecular pathways by which serum supplementation of the culture medium during the preimplantation stage promotes developmental abnormalities, we examined blastocyst morphometry, inner cell mass and trophectoderm cell allocations, macroautophagy, and endoplasmic reticulum stress. On day 5 post-insemination, > 16 cells embryos were selected and cultured in medium containing 10% serum or left as controls. Embryo diameter, inner cell mass and trophectoderm cell number, and macroautophagy were measured on day 8 blastocysts (BL) and expanded blastocysts (XBL). On day 5 and day 8, we assessed transcript level of the ER stress markers HSPA5, ATF4, MTHFD2, and SHMT2 as well as XBP1 splicing (a marker of the unfolded protein response). Serum increased diameter and proliferation of embryos when compared to the no-serum group. In addition, serum increased macroautophagy of BL when compared to controls, while the opposite was true for XBL. None of the genes analyzed was differentially expressed at any stage, except that serum decreased HSPA5 in day 5 > 16 cells stage embryos. XBP1 splicing was decreased in BL when compared to XBL, but only in the serum group. Our data suggest that serum rescues delayed embryos by alleviating endoplasmic reticulum stress and promotes development of advanced embryos by decreasing macroautophagy.

Tauroursodeoxycholic acid/TGR5 signaling promotes survival and early development of glucose-stressed porcine embryos†

Conditions of impaired energy and nutrient homeostasis, such as diabetes and obesity, are associated with infertility. Hyperglycemia increases endoplasmic reticulum stress as well as oxidative stress and reduces embryo development and quality. Oxidative stress also causes deoxyribonucleic acid damage, which impairs embryo quality and development. The natural bile acid tauroursodeoxycholic acid reduces endoplasmic reticulum stress and rescues developmentally incompetent late-cleaving embryos, as well as embryos subjected to nuclear stress, suggesting the endoplasmic reticulum stress response, or unfolded protein response, and the genome damage response are linked. Tauroursodeoxycholic acid acts via the Takeda-G-protein-receptor-5 to alleviate nuclear stress in embryos. To evaluate the role of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling in embryo unfolded protein response, we used a model of glucose-induced endoplasmic reticulum stress. Embryo development was impaired by direct injection of tauroursodeoxycholic acid into parthenogenetically activated oocytes, whereas it was improved when tauroursodeoxycholic acid was added to the culture medium. Attenuation of the Takeda-G-protein-receptor-5 precluded the positive effect of tauroursodeoxycholic acid supplementation on development of parthenogenetically activated and fertilized embryos cultured under standard conditions and parthenogenetically activated embryos cultured with excess glucose. Moreover, attenuation of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling induced endoplasmic reticulum stress, oxidative stress and cell survival genes, but decreased expression of pluripotency genes in parthenogenetically activated embryos cultured under excess glucose conditions. These data suggest that Takeda-G-protein-receptor-5 signaling pathways link the unfolded protein response and genome damage response. Furthermore, this study identifies Takeda-G-protein-receptor-5 signaling as a potential target for mitigating fertility issues caused by nutrient excess-associated blastomere stress and embryo death.

Albumin used in human IVF contain different levels of lipids and modify embryo and fetal growth in a mouse model

PURPOSE

Different commercial human embryo culture mediums can alter embryo quality and change birthweight. One component that could be contributing to variations but is not widely investigated is human serum albumin (HSA). HSA plays a multitude of roles during embryo culture and is a carrier for molecules including lipids. It remains unclear if lipid composition of HSA varies among commercial products and its effects on embryo quality, implantation, and fetal outcomes are relatively unknown.

METHODS

Utilizing a mouse model of embryo culture, we cultured zygotes until the blastocyst stage (72-h culture) in G1/G2 containing either Vitrolife HSA, Sage HSA, or Recombinant HSA at 10%. Blastocyst quality (development, total cell number, superoxide generation), blastocyst lipid content (neutral lipids, non-esterified fatty acids, phospholipids, and triglycerides), implantation, and fetal lengths and weights were assessed. Fatty acid quantification of HSA source was assessed by standard thin-layer chromatography.

RESULTS

Sage HSA had the greatest fatty acid composition, with an eightfold increase in saturated fatty acids. This coincided with reduced blastocyst development, increased superoxide generation, neutral lipids and triglycerides levels of blastocysts, and decreased implantation rates (p < 0.05). Unexpectedly, while Recombinant HSA had the lowest overall lipids it had 70-fold increase in palmitoleic acid and the lowest fetal weights (p < 0.05).

CONCLUSION

Indicates the importance of a balance between different types/amount of lipids, and an "optimal ratio" required for embryo and fetal development. Therefore, the lipid content of HSA should be considered when choosing a suitable HSA source for use in clinical IVF.

Human Pharmacokinetics and Safety of Subcutaneous Collagenase Clostridium Histolyticum in Women

BACKGROUND

Clostridium collagenase histolyticum (CCH) is being evaluated in women as a cellulite treatment.

OBJECTIVE

To report preclinical safety and human pharmacokinetics (PK) and safety data for CCH.

METHODS

Across 3 PK studies, 41 women received 12 subcutaneous injections per thigh/buttock in 1 session (up to 3.36 mg/dose). Blood samples were taken at baseline; at 5, 10, 20, and 30 minutes postdose; and at 1, 2, 4, 8, 12, 24, 48, 168, and 504 hours postdose. In a preclinical study, rats received 0, 0.029, 0.13, or 0.29 mg/dose of CCH intravenously (IV) every other day (QOD) for 16 days (total, 8 doses) and were evaluated for histopathologic changes.

RESULTS

In human PK studies, no quantifiable plasma concentrations of AUX-I or AUX-II were observed postdose (n= 39 evaluable). Adverse events were injection site&ndash;related (bruising [97.6%], pain [87.8%], and edema/swelling [46.3%]). Antidrug antibodies were seen in most women at 504 hours postdose. In rats, plasma concentrations of AUX-I and AUX-II (CCH components) were measurable for 30 minutes and 1-2 hours, respectively, after IV administration. At &ge;43&times; proposed human therapeutic dose on a mg/kg basis, rats experienced elevated liver enzyme levels, increased liver weights, and histologic changes that were mostly reversed during a 14-day recovery period.

CONCLUSIONS

In human studies, no quantifiable circulating CCH levels were observed after a single subcutaneous dose of CCH up to 3.36 mg. Preclinical data indicated that repeat IV dosing (QOD; 8 doses) at &ge;43&times; proposed human dose on a mg/kg basis for CCH was generally well tolerated.J Drugs Dermatol. 2020;19(9):852-856. doi:10.36849/JDD.2020.5048THIS ARTICLE HAD BEEN MADE AVAILABLE FREE OF CHARGE. PLEASE SCROLL DOWN TO ACCESS THE FULL TEXT OF THIS ARTICLE WITHOUT LOGGING IN. NO PURCHASE NECESSARY. PLEASE CONTACT THE PUBLISHER WITH ANY QUESTIONS.

Transcriptomic analyses of gastrulation-stage mouse embryos with differential susceptibility to alcohol

Genetics are a known contributor to differences in alcohol sensitivity in humans with fetal alcohol spectrum disorders (FASDs) and in animal models. Our study profiled gene expression in gastrulation-stage embryos from two commonly used, genetically similar mouse substrains, C57BL/6J (6J) and C57BL/6NHsd (6N), that differ in alcohol sensitivity. First, we established normal gene expression patterns at three finely resolved time points during gastrulation and developed a web-based interactive tool. Baseline transcriptional differences across strains were associated with immune signaling. Second, we examined the gene networks impacted by alcohol in each strain. Alcohol caused a more pronounced transcriptional effect in the 6J versus 6N mice, matching the increased susceptibility of the 6J mice. The 6J strain exhibited dysregulation of pathways related to cell death, proliferation, morphogenic signaling and craniofacial defects, while the 6N strain showed enrichment of hypoxia and cellular metabolism pathways. These datasets provide insight into the changing transcriptional landscape across mouse gastrulation, establish a valuable resource that enables the discovery of candidate genes that may modify alcohol susceptibility that can be validated in humans, and identify novel pathogenic mechanisms of alcohol. This article has an associated First Person interview with the first author of the paper.

Sodium arsenate induced genotoxicity, morphometric and morphological changes in mice embryo and protective role of Moringa oleifera extracts

The present study was carried out to find the comparative ameliorative role of Moringa oleifera leaf and flower extracts against sodium arsenate induced genotoxic, morphometric and morphological changes in mice embryo. Seven to eight week old pregnant females (N=44) with body weight of 20-25g at gestation day zero were divided randomly in groups (A, B, C, D, E, F, G, H, I, J and K). Group A was of control while all others were experimental groups and administered with selected doses of sodium arsenate as toxicant (6mg/kg B.W and 12mg/kg/B.W) and Moringa oleifera leaf and flower extracts as antidote (150mg/kg and 300mg/kg B.W). Significant (p<0.05) amelioration at dose 300mg/kg of Moringa oleifera leaf extract was observed against sodium arsenate induced morphological abnormalities like micromelia, excencephally, cryptothalmia, anopthalmia, laproschisis and morphometric changes like fetus weight, head circumference, crown rump and snout length were observed. Significant protection of DNA was showed in Moringa oleifera leaf extract treated groups (27.50±2.51) as compared to sodium arsenate (66.25±2.75). So concluded that sodium arsenate induced teratogenicity can be decreased using Moringa extract especially of Moringa oleifera leaf extract as it contains bioactive compounds like phenolics.

Small-volume vitrification and rapid warming yield high survivals of one-cell rat embryos in cryotubes†

To cryopreserve cells, it is essential to avoid intracellular ice formation during cooling and warming. One way to achieve this is to convert the water inside the cells into a non-crystalline glass. It is currently believed that to accomplish this vitrification, the cells must be suspended in a very high concentration (20-40%) of a glass-inducing solute, and subsequently cooled very rapidly. Herein, we report that this belief is erroneous with respect to the vitrification of one-cell rat embryos. In the present study, one-cell rat embryos were vitrified with 5 μL of EFS10 (a mixture of 10% ethylene glycol (EG), 27% Ficoll, and 0.45 M sucrose) in cryotubes at a moderate cooling rate, and warmed at various rates. Survival was assessed according to the ability of the cells to develop into blastocysts and to develop to term. When embryos were vitrified at a 2613 °C/min cooling rate and thawed by adding 1 mL of sucrose solution (0.3 M, 50 °C) at a warming rate of 18 467 °C/min, 58.1 ± 3.5% of the EFS10-vitrified embryos developed into blastocysts, and 50.0 ± 4.7% developed to term. These rates were similar to those of non-treated intact embryos. Using a conventional cryotube, we achieved developmental capabilities in one-cell rat embryos by rapid warming that were comparable to those of intact embryos, even using low concentrations (10%) of cell-permeating cryoprotectant and at low cooling rates.

Epigenetic Consequences of in Utero Exposure to Rosuvastatin: Alteration of Histone Methylation Patterns in Newborn Rat Brains

Rosuvastatin (RST) is primarily used to treat high cholesterol levels. As it has potentially harmful but not well-documented effects on embryos, RST is contraindicated during pregnancy. To demonstrate whether RST could induce molecular epigenetic events in the brains of newborn rats, pregnant mothers were treated daily with oral RST from the 11th day of pregnancy for 10 days (or until delivery). On postnatal day 1, the brains of the control and RST-treated rats were removed for Western blot or immunohistochemical analyses. Several antibodies that recognize different methylation sites for H2A, H2B, H3, and H4 histones were quantified. Analyses of cell-type-specific markers in the newborn brains demonstrated that prenatal RST administration did not affect the composition and cell type ratios as compared to the controls. Prenatal RST administration did, however, induce a general, nonsignificant increase in H2AK118me1, H2BK5me1, H3, H3K9me3, H3K27me3, H3K36me2, H4, H4K20me2, and H4K20me3 levels, compared to the controls. Moreover, significant changes were detected in the number of H3K4me1 and H3K4me3 sites (134.3% ± 19.2% and 127.8% ± 8.5% of the controls, respectively), which are generally recognized as transcriptional activators. Fluorescent/confocal immunohistochemistry for cell-type-specific markers and histone methylation marks on tissue sections indicated that most of the increase at these sites belonged to neuronal cell nuclei. Thus, prenatal RST treatment induces epigenetic changes that could affect neuronal differentiation and development.

Different response of embryos originating from control and obese mice to insulin in vitro

The aim of the present work was to investigate the impact of maternal obesity on DNA methylation in ovulated oocytes, and to compare the response of in vitro-developing preimplantation embryos originating from control and obese mice to insulin. An intergenerational, diet-induced obesity model was used to produce outbred mice with an increased body weight and body fat. Two-cell and eight-cell embryos recovered from obese and control mice were cultured in a medium supplemented with 1 or 10 ng/ml insulin until blastocyst formation. In the derived blastocysts, cell proliferation, differentiation, and death rates were determined. The results of immunochemical visualization of 5-methylcytosine indicated a slightly higher DNA methylation in ovulated metaphase II oocytes recovered from obese females; however, the difference between groups did not reach statistical significance. Expanded blastocysts developed from embryos provided by control dams showed increased mean cell numbers (two and eight-cell embryos exposed to 10 ng/ml), an increased inner-cell-mass/trophectoderm ratio (two-cell embryos exposed to 1 ng/ml and eight-cell embryos exposed to 10 ng/ml), and a reduced level of apoptosis (two and eight-cell embryos exposed to 10 ng/ml). In contrast, embryos originating from obese mice were significantly less sensitive to insulin; indeed, no difference was recorded in any tested variable between the embryos exposed to insulin and those cultured in insulin-free medium. Real-time RT-PCR analysis showed a significant increase in the amount of insulin receptor transcripts in blastocysts recovered from obese dams. These results suggest that maternal obesity might modulate the mitogenic and antiapoptotic responses of preimplantation embryos to insulin.

An Embryonic Diapause-like Adaptation with Suppressed Myc Activity Enables Tumor Treatment Persistence

Treatment-persistent residual tumors impede curative cancer therapy. To understand this cancer cell state we generated models of treatment persistence that simulate the residual tumors. We observe that treatment-persistent tumor cells in organoids, xenografts, and cancer patients adopt a distinct and reversible transcriptional program resembling that of embryonic diapause, a dormant stage of suspended development triggered by stress and associated with suppressed Myc activity and overall biosynthesis. In cancer cells, depleting Myc or inhibiting Brd4, a Myc transcriptional co-activator, attenuates drug cytotoxicity through a dormant diapause-like adaptation with reduced apoptotic priming. Conversely, inducible Myc upregulation enhances acute chemotherapeutic activity. Maintaining residual cells in dormancy after chemotherapy by inhibiting Myc activity or interfering with the diapause-like adaptation by inhibiting cyclin-dependent kinase 9 represent potential therapeutic strategies against chemotherapy-persistent tumor cells. Our study demonstrates that cancer co-opts a mechanism similar to diapause with adaptive inactivation of Myc to persist during treatment.

The effect of lutein and Urtica dioica extract on in vitro production of embryo and oxidative status in polycystic ovary syndrome in a model of mice

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrinopathies in women during the reproductive age. Herbal medicines are used increasingly alone or in supplement with chemical medicines for the treatment of different diseases and dysfunctions. This study was aimed to evaluate the effects of lutein and nettle (Urtica dioica) extract on the biochemical parameters and the reproductive function in the PCOS model of mice.

METHODS

Following the induction of PCOS by dehydroepiandrosterone (DHEA), the mice (n = 98) were randomly assigned into seven groups, each consisting of fourteen mice; the groups were included control group (received solvent), PCOS group (received 6 mg/100 g B.W/day IP, DHEA for 21 days), PCOS+ Nettle extract (200 and 400 mg/kg), PCOS+ Lutein (125 and 250 mg/kg), and PCOS+ NL (200 mg/kg nettle extract and 125 mg/kg lutein). The nettle extract and lutein were administrated using gavage for 30 consecutive days after PCOS induction. Malondialdehyde (MDA), total antioxidant capacity (TAC), and estrogen were measured in serum, ovary, and uterus samples by the ELISA method. The total number of oocytes, oocyte quality, fertilization rate, 2-cell blastocyst, and arrested embryos (type I, type II, and type III) were also investigated.

RESULTS

A combination treatment of the nettle and lutein produced the lowest concentration of MDA in comparison to other groups which affected by the PCOS. The lowest level of TAC was observed in the PCOS group without treatment. The number of oocytes, oocyte quality, fertilization rate, and 2-cell blastocyst were significantly higher in the control group, but the lowest values were observed in the PCOS group without any treatment.

CONCLUSIONS

The most favorable findings include improving antioxidant capacity, oocyte and embryo quality were observed in the PCOS+ 125 L group.

Improved cryopreservation of in vitro produced bovine embryos using FGF2, LIF, and IGF1

In vitro embryo production systems are limited by their inability to consistently produce embryos with the competency to develop to the blastocyst stage, survive cryopreservation, and establish a pregnancy. Previous work identified a combination of three cytokines [fibroblast growth factor 2 (FGF2), leukemia inhibitory factor (LIF), and insulin-like growth factor 1 (IGF1)], called FLI, that we hypothesize improve preimplantation development of bovine embryos in vitro. To test this hypothesis, FLI was supplemented into oocyte maturation or embryo culture medium. Embryos were produced in vitro using abattoir-derived oocytes and fertilized with sperm from a single bull known to have high fertility. After an 18-20 h fertilization period, putative zygotes were cultured in synthetic oviductal fluid (SOF) for 8 days. The addition of FLI to the oocyte maturation medium increased (P < 0.05) the dissociation of transzonal projections at 12, 18, and 24 h of maturation, as well as, the proportion of oocytes that reached the metaphase II stage of meiosis. Additionally, lipid content was decreased (P < 0.05) in the blastocyst stage embryo. The addition of FLI during the culture period increased development to the blastocyst stage, cytoskeleton integrity, and survival following slow freezing, as well as, decreased post thaw cell apoptosis (P < 0.05). In conclusion, the supplementation of these cytokines in vitro has the potential to alleviate some of the challenges associated with the cryo-survival of in vitro produced bovine embryos through improving embryo development and embryo quality.

Leptin improves the in vitro development of preimplantation rabbit embryos under oxidative stress of cryopreservation

Vitrification is an economically effective method for embryo cryopreservation in human and livestock animals; however, it carries the risk of damage by the exposure to severe oxidative stress. The present study was conducted to evaluate the effect of leptin at different levels on the in vitro development of fresh and vitrified preimplantation embryos in a rabbit model. Normal embryos at morulae stage were randomly cultured for 2 h with 0, 10, 20 or 100 ng/mL of leptin, then were cultured for further 48 h as freshly or after vitrification. Thereafter, developed blastocysts form the best leptin level in fresh and vitrified embryos along with their controls were allocated to analyze the pro-oxidant (malondialdehyde, MDA; nitric oxide, NO), antioxidant (total antioxidant capacity, TAC; superoxide dismutase, SOD; glutathione peroxidase, GPx), apoptotic (Bcl-2 associated X protein, BAX; heat shock 60kD protein member 1, HSP60; tumor necrosis factor alpha, TNFα) and developmental (sex determining region Y box protein 2, SOX2; Nanog homeobox protein, NANOG; Octamer-binding protein 4, OCT4) biomarkers. Results indicate that expanding and hatching rates of embryos were significantly higher at 20 ng/mL leptin than the other levels, while vitrification had an independent suppression effect on the in vitro development rates. The MDA and NO were significantly higher, while TAC, SOD and GPx were significantly lower in the vitrified than fresh embryos. In contrast, leptin treatment significantly decreased the pro-oxidant biomarkers and increased the antioxidant biomarkers in both fresh and vitrified embryos. Vitrification significantly increased the antiapoptotic biomarkers, and decreased the developmental biomarkers in embryos. In contrast, leptin decreased the BAX and TNFα, increased the HSP60, and moreover, ameliorated the reduction of developmental biomarkers in the vitrified embryos. These results conclude that leptin could be used as antiapoptotic and antioxidant promotor to support the in vitro embryonic development, particularly under oxidative stress emerged from cryopreservation programs.

Stage-specific response in early mouse embryos exposed to prednisolone in vitro

Corticosteroids are increasingly being used during the peri-implantation period to treat women with repeated IVF failure and recurrent miscarriage. However, the direct effects of prednisolone (PRDL), one of the commonly used corticosteroids on early embryo development is not understood. To mimic the possible clinical scenario and to understand the embryonic response to direct PRDL exposure, this pilot study was conducted in a mouse model. Cleavage stage embryos exposed to 3 and 30 µM PRDL in vitro were assessed for peri-implantation developmental potential, genetic integrity, inner cell mass (ICM) proliferation and pluripotency markers in the proliferated ICM cells. Exposure to 30 µM PRDL delayed the embryonic progression beyond compaction (P < 0.05) in comparison to vehicle control and, had reduced total cell number (P < 0.001) than all other groups. In addition, 30 µM PRDL exposure resulted in poor hatching potential (P < 0.05) and increased apoptosis in blastocysts (P < 0.05) compared to 3 µM PRDL. On the other hand, completely formed ICM outgrowths were significantly higher (P < 0.05) in 3 µM PRDL compared to control. However, no significant differences were observed in the expression of pluripotency genes. In conclusion, the trend observed in embryos exposed to PRDL in vitro provides important information concerning the use of this drug when treating patients at the peri-implantation phase of IVF cycles. However, the clinical value of this observation on human embryo development needs further research.

Colorectal Cancer Cells Enter a Diapause-like DTP State to Survive Chemotherapy

Cancer cells enter a reversible drug-tolerant persister (DTP) state to evade death from chemotherapy and targeted agents. It is increasingly appreciated that DTPs are important drivers of therapy failure and tumor relapse. We combined cellular barcoding and mathematical modeling in patient-derived colorectal cancer models to identify and characterize DTPs in response to chemotherapy. Barcode analysis revealed no loss of clonal complexity of tumors that entered the DTP state and recurred following treatment cessation. Our data fit a mathematical model where all cancer cells, and not a small subpopulation, possess an equipotent capacity to become DTPs. Mechanistically, we determined that DTPs display remarkable transcriptional and functional similarities to diapause, a reversible state of suspended embryonic development triggered by unfavorable environmental conditions. Our study provides insight into how cancer cells use a developmentally conserved mechanism to drive the DTP state, pointing to novel therapeutic opportunities to target DTPs.

Vitrification of Equine In Vivo-Derived Embryos After Blastocoel Aspiration

Embryo cryopreservation is normally performed with great success in species like humans and cattle. The large size of in vivo-derived equine embryos and the presence of a capsule-impermeable to cryoprotectants-have complicated the use of embryo cryopreservation in equine reproduction. A breakthrough for this technique was obtained when large equine embryos could be successfully cryopreserved after collapsing the blastocoel cavity using a micromanipulation system. High pregnancy rates have been obtained when vitrification is used in combination with embryo collapse.

Comparison of Pregnancy and Neonatal Outcomes of Single Frozen Blastocyst Transfer Between Letrozole-Induction and HRT Cycles in Patients With Abnormal Ovulation

BACKGROUND

The use of frozen embryo transfer (FET) cycles has dramatically risen. The optimal endometrial preparation method for women undergoing FET is of utmost importance to provide the optimal chances of pregnancy. For patients with abnormal ovulation in particular, there have been few studies on FET protocols; notably, most of these studies focus only on the clinical pregnancy rate or live birth rate (LBR) and pay little attention to the regimen's safety for offspring.

METHODS

It was a retrospective cohort study. First FET cycle with a single blastocyst from whole embryo frozen IVF/ICSI at the Reproductive Center of Third Affiliated Hospital of Zhengzhou University between January 2016 and January 2020. The LBR was the primary outcome of interest. The secondary outcome measures were miscarriage rate and offspring safety, including preterm birth, low birthweight (LBW), small-for-gestational age (SGA), macrosomia and large-for-gestational age (LGA).

RESULTS

In total, 2782 FET cycles met the eligibility criteria for analysis. Additionally, there were 1178 singleton births from FET cycles. The clinical pregnancy rate was 58.4% in the L-FET group and 54.5% in the HRT group, with no statistical significance (P=.116). The miscarriage rate was higher in the HRT group than in the L-FET group (21.7% vs. 14.3%, P=.005). The LBR was significantly higher in the L-FET group than in the HRT group (49.6% vs. 41.7%, P=.001). Neonatal outcomes were similar between the two groups. After adjustments for confounding factors, the LBR was higher in the L-FET group (aOR 1.30, 95% CI 1.06-1.58). The rate of miscarriage was lower in the L-FET group (aOR 0.63, 95% CI 0.44-0.90).

CONCLUSION

For patients with abnormal ovulation, the L-FET regimen has a higher LBR and lower miscarriage rate than HRT. The neonatal outcomes were similar between the two groups.

Generation and Characterization of Inducible Lung and Skin-Specific IL-22 Transgenic Mice

IL-22 is an IL-10 family cytokine that is increased in asthma and atopic dermatitis (AD). However, the specific role of IL-22 in the pathogenesis of allergic lung inflammation and AD in vivo has yet to be elucidated. We aimed to develop mouse models of allergic diseases in the lung and skin with inducible and tissue-specific expression of IL-22, using a tetracycline (Tet)-controlled system. In this chapter, we describe a series of protocols we have developed to generate a construct that contains the TRE-Tight promoter and mouse IL-22 cDNA based on this system. Furthermore, we describe how to generate TRE-Tight-IL-22 mice through pronuclear microinjection. In our approach, two Tet-on (CC10-rtTA or SPC-rtTA) and a Tet-off (K5-tTA) transgenic mouse lines are selected to crossbreed with TRE-Tight-IL-22 mice to generate inducible tissue-specific transgenic lines. The transgenic strains, CC10-rtTA/TRE-Tight-IL-22 (CC10-rtTA-IL-22) or SPC-rtTA/TRE-Tight-IL-22 (SPC-rtTA-IL-22) mice, do not produce detectable levels of IL-22 in their bronchoalveolar lavage (BAL) samples in the absence of doxycycline (Dox). However, oral Dox treatment of these mice induces IL-22 expression in the BAL, and the airway and lung epithelial cells. For K5-tTA/TRE-Tight-IL-22 (K5-tTA-IL-22) mice, to avoid potential IL-22 toxicity to mouse embryos, Dox is given starting at the time of breeding to suppress tTA and to keep the IL-22 transgene off until the K5-tTA-IL-22 mice are 6 weeks old. Experiments are then initiated by withdrawing Dox from the drinking water. In all cases, IL-22 protein can be detected by immunohistochemistry in the skin of Tg(+) animals, but not in the skin of Tg(-) animals. Utilizing transgenic technology based on the Tetracycline-controlled system, we have established inducible transgenic mouse models in which cytokine IL-22 can be expressed specifically in the lung or skin. These models are valuable for studies in vivo in a broad range of diseases involving IL-22 and will provide a new platform for research and for seeking novel therapeutics in the fields of inflammation, asthma, and allergic dermatitis.

Knockout mouse models are predictive of malformations or embryo-fetal death in drug safety evaluations

Traditionally, understanding potential developmental toxicity from pharmaceutical exposures has been based on the results of ICH guideline studies in two species. However, support is growing for the use of weight of evidence approaches when communicating the risk of developmental toxicity, where the intended pharmacologic mode of action affects fundamental pathways in developmental biology or phenotypic data from genetically modified animals may increasingly be included in the overall assessment. Since some concern surrounds the use of data from knockout (KO) mice to accurately predict the risk for pharmaceutical modulation of a target, a deeper understanding of the relevance and predictivity of adverse developmental effects in KO mice for pharmacological target modulation is needed. To this end, we compared the results of embryo-fetal development (EFD) studies for 86 drugs approved by the FDA from 2017 to 2019 that also had KO mouse data available in the public domain. These comparisons demonstrate that data from KO mouse models are overall highly predictive of malformations or embryo-fetal lethality (MEFL) from EFD studies, but less so of a negative outcome in EFD studies. This information supports the use of embryo-fetal toxicity data in KO models as part of weight of evidence approaches in the communication of developmental toxicity risk of pharmaceutical compounds.

Valproic acid alters nitric oxide status in neurulating mouse embryos

The molecular bases of the teratogenic effects elicited by valproic acid (VPA) are not fully defined. It was previously shown that inhibition of nitric oxide (NO) synthesis is associated with an enhancement of the teratogenic effects of VPA, while amplification of NO signal by sildenafil prompted a dose-dependent reduction of VPA-induced neural tube defects. In this study, for the first time, the effect of VPA on the NO synthesis was evaluated in mouse embryos during early organogenesis. On gestation day 8, ICR-CD1 mice received 600 mg/kg of VPA. Eight and 24 h later embryos were collected and analyzed for NO synthase (NOS) isoform expression, and for molecular mechanisms involved in their modulation. As main finding, in utero embryonic exposure to VPA determined a time-dependent shift of NOS isoforms expression, with a down regulated expression and activity of constitutive NOS (cNOS) and an increased expression and activity of inducible NOS (iNOS). The teratological relevance of this information remains to be established.

Effects of bisphenol A and bisphenol S on microRNA expression during bovine (Bos taurus) oocyte maturation and early embryo development

Bisphenol A (BPA) and its alternative, bisphenol S (BPS), are widespread endocrine disrupting compounds linked in several studies to poor female fertility. Sufficient oocyte competence and subsequent embryo development are highly dependent on oocyte maturation, an intricate process that is vulnerable to BPA. These effects as well as the effects of its analog, BPS, have not been fully elucidated. Although the harmful consequences of bisphenols on the reproductive system are largely due to interferences with canonical gene expression, more recent evidence implicates noncoding RNAs, including microRNAs (miRNA), as significant contributors. The aim of this work was to test the hypothesis that abnormal expression of key miRNAs during oocyte maturation and embryo development occurs following BPA and BPS exposure during maturation. Using qPCR, primary and mature forms of miR-21, -155, -34c, -29a, -10b, -146a were quantified in an in vitro bovine model of matured cumulus-oocyte complexes, fertilized embryos, and cultured cumulus cells after exposure to BPA or BPS at the LOAEL dose (0.05 mg/mL). Expression of miR-21, miR -155, and miR-29a were markedly increased (P = 0.02, 0.04, <0.0001) while miR-34c and miR-10b were decreased (P = 0.01, 0.01), after BPA treatment. miR-146a expression remained stable. BPS had no effects, suggesting may not exert its actions through these six miRNAs examined. Overall, this study indicates that BPA effects are likely miRNA specific rather than a global effect on miRNA synthesis and processing mechanisms and that its analog, BPS, may not possess the same properties required to interfere with these miRNAs during bovine oocyte maturation.

Maternal hepcidin determines embryo iron homeostasis in mice

Iron disorders are associated with adverse pregnancy outcomes, yet iron homeostatic mechanisms during pregnancy are poorly understood. In humans and rodents, the iron-regulatory hormone hepcidin is profoundly decreased in pregnant mothers, which is thought to ensure adequate iron availability for transfer across placenta. However, the fetal liver also produces hepcidin, which may regulate fetal iron endowment by controlling placental iron export. To determine the relative contribution of maternal vs embryo hepcidin to the control of embryo iron endowment in iron-sufficient or iron-overloaded mice, we generated combinations of mothers and embryos that had or lacked hepcidin. We found that maternal, but not embryonic, hepcidin determined embryo and placental iron endowment in a healthy pregnancy. We further determined that inflammation can counteract pregnancy-dependent suppression of maternal hepcidin. To establish how essential maternal hepcidin suppression is for embryo iron homeostasis, we mimicked the range of maternal hepcidin activity by administering a hepcidin peptide mimetic to pregnant mice. This also allowed us to determine the effect of isolated maternal hepcidin excess on pregnancy, in the absence of other confounding effects of inflammation. Higher doses of hepcidin agonist caused maternal iron restriction and anemia, lower placenta and embryo weight, embryo anemia, and increased embryo mortality. Low agonist doses did not cause maternal anemia but still adversely affected the embryo, causing anemia, tissue iron deficiency (including in the brain), and decreased weight. Our studies demonstrate that suppression of maternal hepcidin during pregnancy is essential for maternal and embryo iron homeostasis and health.

Graphene Quantum Dots' Surface Chemistry Modulates the Sensitivity of Glioblastoma Cells to Chemotherapeutics

Recent evidence has shown that graphene quantum dots (GQDs) are capable of crossing the blood-brain barrier, the barrier that reduces cancer therapy efficacy. Here, we tested three alternative GQDs' surface chemistries on two neural lineages (glioblastoma cells and mouse cortical neurons). We showed that surface chemistry modulates GQDs' biocompatibility. When used in combination with the chemotherapeutic drug doxorubicin, GDQs exerted a synergistic effect on tumor cells, but not on neurons. This appears to be mediated by the modification of membrane permeability induced by the surface of GQDs. Our findings highlight that GQDs can be adopted as a suitable delivery and therapeutic strategy for the treatment of glioblastoma, by both directly destabilizing the cell membrane and indirectly increasing the efficacy of chemotherapeutic drugs.

Expression of Fibroblast Growth Factor 4 in a Rat Model of Polydactyly of the Thumb Induced by Cytarabine

BACKGROUND The aim of this study was to assess the expression and mechanisms of fibroblast growth factor 4 in polydactyly of the thumb induced by cytarabine. MATERIAL AND METHODS Rats were intraperitoneally injected with cytarabine at different gestation periods (12.5 days, 13.5 days, and 14.5 days) to establish a polydactyly of the thumb model. Then, the expression of FGF4 in polydactyly was studied by whole-mount in situ hybridization. We used hematoxylin & eosin stain and cartilage stain to investigate the development of the skeleton and tissues in the embryo. Pictures were taken to determine the general shape of the deformity, then X-rays were taken to detect bone distortion of the rats born with a congenital malformation. RESULTS In the experimental group (11.5 days, 12.5 days, 13.5 days, and 14.5 days), whole-mount in situ hybridization showed that the FGF4 expression at the tip of the embryonic limb bud was significantly increased compared with the control group and FGF4 was distributed in a wider range and lasted longer than in the control group (P<0.01). HE staining and cartilage staining showed that there was an extra metacarpal bone and a phalanx in the rats with polydactyly of the thumb (P<0.01). Images of the deformed limbs showed polydactyly and syndactyly of the thumb in the rats. Further X-ray examination revealed 1 extra metacarpal bone and 1 extra phalanx. CONCLUSIONS Cytarabine can induce polydactyly and syndactyly of the thumb in rats. In this process, cytarabine can induce the expression of FGF4 on the tip of the embryonic limb bud, which further leads to abnormal development of the embryonic limb bud and eventually causes a congenital deformity.

Sub-lethal toxicity assessment of the phenylurea herbicide linuron in developing zebrafish (Danio rerio) embryo/larvae

Due to run-off and rain events, agrochemicals can enter water catchments, exerting endocrine disruption effects and toxicity to aquatic organisms. Linuron is a phenylurea herbicide used to control a wide variety of vegetative weeds in agriculture in addition to residential applications. However, there are few studies that quantify its toxicity to early developmental stages of fish. The objectives of this study were to assess the acute toxicity of linuron to zebrafish embryos/larvae by measuring mortality, morphological deformities, oxidative respiration, gene expression, and locomotor activity via the Visual Motor Response test. Zebrafish embryos at ~6-h post-fertilization (hpf) were exposed to either embryo rearing medium (ERM), or one dose of 0.625, 1.25, 2.5, 5, and 10 μM linuron for up to 7 days post-fertilization (dpf) depending on the assay. Zebrafish larvae exposed to linuron displayed pericardial edema, yolk sac edema, and spinal curvature. Oxidative respiration assessments in embryos using the Agilent XF^e24 Flux Analyzer revealed that linuron decreased mean basal respiration and oligomycin-induced ATP-linked respiration in 30 hpf embryos at 20 μM after a 24-hour exposure. In 7 dpf larvae, transcript abundance was determined for 6 transcripts that have a role in oxidative respiration (atp06, cox1, cox4-1, cox5a1, cytb, and nd1); the relative abundance of these transcripts was not altered with linuron treatment. A Visual Motor Response test was conducted on 7 dpf larvae to determine whether linuron (0.625 to 5 μM) impaired locomotor activity. Larval activity in the dark period decreased in a dose dependent manner and there were indications of hypoactivity as low as 1.25 μM. Transcript abundance was thus determined for tyrosine hydroxylase (th1) and glutamic acid decarboxylase 67 (gad1b), two rate limiting enzymes that control the production of dopamine and gamma-aminobutyric acid respectively. The mRNA levels of gad1b (p = 0.019) were reduced with increasing concentrations of linuron while th1 (p = 0.056) showed a similar decreasing trend, suggesting that neurotransmitter biosynthesis may be altered with exposure to linuron. This study improves knowledge related to the toxicity mechanisms for linuron and is the first to demonstrate that this anti-androgenic chemical impairs oxidative respiration and exerts neurotoxic effects associated with neurotransmitter biosynthesis during early development. These data are significant for environmental risk assessment of agrochemicals.

Early prepubertal cyclophosphamide exposure in mice results in long-term loss of ovarian reserve, and impaired embryonic development and blastocyst quality

Background

Due to improved treatment, there is an increasing focus on the reproductive potential of survivors of childhood cancer. Cytotoxic chemotherapy accelerates the decline in the number of primordial follicles within the mammalian ovary at all ages, but effects on the developmental potential of remaining oocytes following prepubertal cancer treatment are unclear.

Objectives

To investigate whether cyclophosphamide (CY) exposure in the prepubertal period in female mice influences ovarian function and the functional competence of oocytes in adulthood.

Methods

This study used Swiss albino mice as the experimental model. Female mice were treated with 200 mg/kg CY on either postnatal day 14 (CY14), 21 (CY21) or 28 (CY28) i.e at a prepubertal and 2 young postpubertal ages. At 14 weeks of life, ovarian function, functional competence of oocytes, and embryo quality were assessed.

Results

The number of primordial follicles decreased significantly in CY14 and CY21 groups compared to control (p < 0.01). The number of oocytes from superovulated was 8.5 ± 1.4, 24.1 ± 2.9 and 26.8 ± 2.1 in CY14, CY21 and CY28 respectively which was significantly lower than control (50.2 ± 3.2; p < 0.001). In vitro culture of CY14 embryos demonstrated only 55.4% blastocyst formation (p < 0.0001) and reduced ability of inner cell mass (ICM) to proliferate in vitro (p < 0.05) at 120 and 216 h post insemination respectively. On the other hand, ICM proliferation was unaltered in 2 young postpubertal ages.

Conclusion

Our results indicate long-term effects on the developmental competence of oocytes exposed to CY in early but not adult life. These data provide a mechanism whereby long-term fertility can be impaired after chemotherapy exposure, despite the continuing presence of follicles within the ovary, and support the need for fertility preservation in prepubertal girls before alkylating agent exposure.

An Improved Nanoemulsion Formulation Containing Kojic Monooleate: Optimization, Characterization and In Vitro Studies

Tyrosinase inhibitors have become increasingly important targets for hyperpigmentation disease treatment. Kojic monooleate (KMO), synthesized from the esterification of kojic acid and oleic acid, has shown a better depigmenting effect than kojic acid. In this study, the process parameters include the speed of high shear, the time of high shear and the speed of the stirrer in the production of nanoemulsion containing KMO was optimized using Response Surface Methodology (RSM), as well as evaluated in terms of its physicochemical properties, safety and efficacy. The optimized condition for the formulation of KMO nanoemulsion was 8.04 min (time of high shear), 4905.42 rpm (speed of high shear), and 271.77 rpm (speed of stirrer), which resulted in a droplet size of 103.97 nm. An analysis of variance (ANOVA) showed that the fitness of the quadratic polynomial fit the experimental data with large F-values (148.79) and small p-values (p < 0.0001) and an insignificant lack of fit. The optimized nanoemulsion containing KMO with a pH value of 5.75, showed a high conductivity value (3.98 mS/cm), which indicated that the nanoemulsion containing KMO was identified as an oil-in-water type of nanoemulsion. The nanoemulsion remains stable (no phase separation) under a centrifugation test and displays accelerated stability during storage at 4, 25 and 45 °C over 90 days. The cytotoxicity assay showed that the optimized nanoemulsion was less toxic, with a 50% inhibition of cell viability (IC₅₀) > 500 μg/mL, and that it can inhibit 67.12% of tyrosinase activity. This study reveals that KMO is a promising candidate for the development of a safe cosmetic agent to prevent hyperpigmentation.

Glyphosate Induces Metaphase II Oocyte Deterioration and Embryo Damage by Zinc Depletion and Overproduction of Reactive Oxygen Species

Glyphosate is the most popular herbicide used in modern agriculture, and its use has been increasing substantially since its introduction. Accordingly, glyphosate exposure from food and water, the environment, and accidental and occupational venues has also increased. Recent studies have demonstrated a relationship between glyphosate exposure and a number of disorders such as cancer, immune and metabolic disorders, endocrine disruption, imbalance of intestinal flora, cardiovascular disease, and infertility; these results have given glyphosate a considerable amount of media and scientific attention. Notably, glyphosate is a powerful metal chelator, which could help explain some of its effects. Recently, our findings on 2,3-dimercapto-1-propanesulfonic acid, another metal chelator, showed deterioration of oocyte quality. Here, to generalize, we investigated the effects of glyphosate (0 - 300 μM) on metaphase II mouse oocyte quality and embryo damage to obtain insight on its mechanisms of cellular action and the tolerance of oocytes and embryos towards this chemical. Our work shows for the first time that glyphosate exposure impairs metaphase II mouse oocyte quality via two mechanisms: 1) disruption of the microtubule organizing center and chromosomes such as anomalous pericentrin formation, spindle fiber destruction and disappearance, and defective chromosomal alignment and 2) substantial depletion of intracellular zinc bioavailability and enhancement of reactive oxygen species accumulation. Similar effects were found in embryos. These results may help clarify the effects of glyphosate exposure on female fertility and provide counseling and preventative steps for excessive glyphosate intake and resulting oxidative stress and reduced zinc bioavailability.

Porcine embryo collection using single subcutaneous administration of follicle-stimulating hormone in a large volume of saline

The effects of a single subcutaneous or intramuscular injection of follicle-stimulating hormone (FSH) on follicular growth and expression of estrous behavior and its single subcutaneous administration on the number of corpora lutea (CL) and embryos were investigated in pigs. All four sows that were subcutaneously administered 5 AU FSH expressed normal estrus and had no ovarian cysts. Two of the four sows that were administered 5 AU FSH intramuscularly did not exhibit estrus, and another sow had a short estrus period. All four sows had ovarian cysts. The mean numbers of CL, embryos, and blastocysts following the subcutaneous administration of 5 AU FSH (16.8, 16.0, and 13.8, respectively) did not differ significantly from those for the control animals treated intramuscularly with 1000 IU equine chorionic gonadotropin (18.5, 16.5, and 14.3, respectively). In conclusion, embryo recovery was possible using a single subcutaneous administration of FSH.

Contribution of increasing plasma membrane to the energetic cost of early zebrafish embryogenesis

How do early embryos allocate the resources stored in the sperm and egg? Recently, we established isothermal calorimetry to measure heat dissipation by living zebra-fish embryos and to estimate the energetics of specific developmental events. During the reductive cleavage divisions, the rate of heat dissipation increases from ∼60 nJ · s-1 at the two-cell stage to ∼90 nJ · s-1 at the 1024-cell stage. Here we ask which cellular process(es) drive this increasing energetic cost. We present evidence that the cost is due to the increase in the total surface area of all the cells of the embryo. First, embryo volume stays constant during the cleavage stage, indicating that the increase is not due to growth. Second, the heat increase is blocked by nocodazole, which inhibits DNA replication, mitosis, and cell division; this suggests some aspect of cell proliferation contributes to these costs. Third, the heat increases in proportion to the total cell surface area rather than total cell number. Fourth, the heat increase falls within the range of the estimated costs of maintaining and assembling plasma membranes and associated proteins. Thus, the increase in total plasma membrane associated with cell proliferation is likely to contribute appreciably to the total energy budget of the embryo.

Meiotic block with roscovitine improves competence of porcine oocytes by fine-tuning activities of different cyclin-dependent kinases

Successful use of oocytes from small follicles (SFs) is of great importance for animal embryo production and human in vitro fertilization with reduced hormone-related side effects. How in vitro meiotic arrest maintenance (MAM) increases the competence of oocytes is not clear. In this study, pig oocytes recovered from SF of 1-2 mm and medium-follicles (MF) of 3-6 mm in diameter from abattoir ovaries were treated by various MAM treatments to improve their competence. The results showed that 25 µM roscovitine or 1 mM db-cAMP efficiently blocked germinal vesicle breakdown in both SF and MF oocytes suggesting a similar cyclin-dependent kinase (CDK) 1 level between the two oocyte groups. MAM with 15- and 25-µM roscovitine alone or with 1-mM db-cAMP improved competence of SF and MF oocytes, respectively, with a promoted chromatin configuration transition from surrounded nucleoli (SN) to re-decondensation (RDC) pattern that supported substantial gene transcription. However, MAM with db-cAMP alone or with higher concentrations of roscovitine did not improve oocyte competence, could not support an SN-to-RDC transition, and/or evoked a premature chromatin condensation (PMC) that suppressed gene transcription. Both CDK2 and CDK5 contents were higher (p < .05) in MF than in SF oocytes. It is concluded that the competence of pig oocytes, particularly that of SF oocytes can be improved by MAM using a proper roscovitine concentration that promotes gene transcription by inhibiting CDK5 while letting CDK2 off to prevent PMC.

Oral Co-Exposures to zinc oxide nanoparticles and CdCl2 induced maternal-fetal pollutant transfer and embryotoxicity by damaging placental barriers

Synergistic toxicity from multiple environmental pollutants poses greater threat to humans, especially to susceptible pregnant population. Here we evaluated combined toxicity from environment pollutants zinc oxide nanoparticles (ZnO NPs) and cadmium chloride (CdCl₂) using two pregnant mice models established by oral administration during peri-implantation or organogenesis period. We found that exposures to combined pollutants only at organogenesis stage induced higher fetal deformity rate compared to co-exposures at peri-implantation stage. We further discovered that surface charge of ZnO NPs were modified after Cd²⁺ adsorption and the resulting nanoadducts caused more severe damages in placental barriers by causing shed endothelial cells and decreased expressions of tight junction proteins ZO1, occludin, claudin-4 and claudin-8. These cellular and molecular events enhanced maternal-fetal transfer of both pollutants and aggravated embryotoxicity. Our findings help elucidate synergistic embryotoxicity by nanoparticle/pollutant adducts and establish proper safety criteria for pregnant population in an era that nanotechnology-based products are widely used.

How to improve mouse cloning

The mouse is the most extensively used mammalian laboratory species in biology and medicine because of the ready availability of a wide variety of defined genetic and gene-modified strains and abundant genetic information. Its small size and rapid generation turnover are also advantages compared with other experimental animals. Using these advantages, somatic cell nuclear transfer (SCNT) in mice has provided invaluable information on epigenetics related to SCNT technology and cloning, playing a leading role in relevant technical improvements. These improvements include treatment with histone deacetylase inhibitors, correction of Xist gene expression (controlling X chromosome inactivation), and removal of methylated histones from SCNT-generated embryos, which have proven to be effective for SCNT cloning of other species. However, even with the best combination of these treatments, the birth rate in cloned offspring is still lower than intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF). One remaining issue associated with SCNT is placental enlargement (hyperplasia) found in late pregnancy, but this abnormality might not be a major cause for the low efficiency of SCNT because many SCNT-derived embryos die before their placentas start to enlarge at midgestation (early postimplantation stage). It is known that, at this stage, undifferentiated trophoblast cells in the extraembryonic tissue of SCNT-derived embryos fail to proliferate. Understanding the molecular mechanisms is essential for further technical improvements of mouse SCNT, which might also provide clues for technical breakthroughs in mammalian SCNT and cloning in general.

l-carnitine reduces the adverse effects of ROS and up-regulates the expression of implantation related genes in in vitro developed mouse embryos

In vitro developed embryos are inevitably exposed to various reactive oxygen species (ROS) which may decrease the embryo's competence in assisted reproductive technology (ART) procedures. Optimization of embryo culture media using antioxidant agents could help to improve embryo quality and could overcome failures in current ART. The aim of this study was to evaluate the effects of l-carnitine (LC), an enhancer of mitochondrial activity and free radical scavenger, in culture media on early embryo competence and expression of ErbB1 and ErbB4 implantation related genes. Two-cell mouse embryos were cultured in the following four conditions: 1. LC group in media containing LC; 2.H ₂O₂ group exposed to H₂O₂ for 30 min and then transferred into a simple media; 3.H₂O₂+LC group exposed to H₂O₂ for 30 min and then transferred into a simple media containing LC; 4.the control group kept throughout in simple media. All groups were allowed to develop until the blastocyst stage. ErbB1 and ErbB4 expression were evaluated by Real-time PCR and immunocytochemistry. The expression of Sirt3 gene was also evaluated. Intracellular ROS levels were examined by DCFH-DA fluorescence intensity. In order to assess the morphological quality of the embryos, ICM and OCM number blastocyst cells were evaluated by using Hoechst and propidium iodide (PI) staining. ErbB1, ErbB4, ROS levels and cell number were compared across all in vitro groups. Our data reveal that LC significantly increases ErbB1 and ErbB4 gene and protein expression with intracellular ROS levels and Sirt3 gene expression significantly decreased after LC treatment. It is worth noting that an elevated cell number was observed in the LC-treated group compared with the other groups suggesting increased viability and/or proliferation. Our findings suggest that the use of LC could be helpful to improve preimplantation embryo culture media through its effects in decreasing ROS levels and the increase of implantation-related genes.

Intraindividual Embryo Morphokinetics Are Not Affected by a Switch of the Ovarian Stimulation Protocol Between GnRH Agonist vs. Antagonist Regimens in Consecutive Cycles

Background: The impact of controlled ovarian stimulation (COS) during medically assisted reproduction (MAR) on human embryogenesis is still unclear. Therefore, we investigated if early embryonic development is affected by the type of gonadotropin-releasing hormone (GnRH) analog used to prevent a premature LH surge. We compared embryo morphology and morphokinetics between GnRH agonist and antagonist cycles, both involving human chorionic gonadotropin (hCG)-trigger. To reduce possible confounding factors, we used intraindividual comparison of embryo morphokinetics in consecutive treatment cycles of the same patients that underwent a switch in the COS protocol. Methods: This retrospective cohort study analyzed morphokinetics of embryos from patients (n = 49) undergoing a switch in COS protocols between GnRH agonists followed by GnRH antagonists, or vice versa, after culture in a time-lapse incubator (EmbryoScope®, Vitrolife) in our clinic between 06/2011 and 11/2016 (n = 49 GnRH agonist cycles with n = 172 embryos; n = 49 GnRH antagonist cycles with n = 163 embryos). Among time-lapse cycles we included all embryos of the two consecutive cycles before and after a switch in the type of COS in the same patient. In-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) was performed and embryos were imaged up to day 5. Data were analyzed using Mann-Whitney U test or Fisher's exact test. The significance level was set to p = 0.05. Patients with preimplantation genetic screening cycles were excluded. Results: The mean age (years ± standard deviation) of patients at the time of treatment was 35.7 ± 4.3 (GnRH agonist) and 35.8 ± 4.0 (GnRH antagonist) (p = 0.94). There was no statistically significant difference in the number of oocytes collected or the fertilization rate. The numbers of top quality embryos (TQE), good-quality embryos (GQE), or poor-quality embryos (PQE) were also not different in GnRH agonist vs. antagonist cycles. We found no statistically significant difference between the analyzed morphokinetic parameters between the study groups. Conclusions: Our finding supports the flexible use of GnRH analogs to optimize patient treatment for COS without affecting embryo morphokinetics.

A novel "embryo-endometrial" adhesion model can potentially predict "receptive" or "non-receptive" endometrium

OBJECTIVE

To establish a model of human implantation that responds to hormonal stimuli and can differentiate between endometrium from fertile women and those with idiopathic infertility.

DESIGN

A trophoblast stem cell (trophectodermal) line (TSC; derived from human pre-implantation embryo) was used to form trophectodermal spheroids (TS). TS attachment to monolayers of endometrial epithelial cell lines or primary endometrial epithelial cells (pHEECs) was determined.

SETTING

Independent Medical Research Institute with close clinical linkages INTERVENTIONS: Spheroid attachment and outgrowth was determined with added hormones (estradiol 17β (E), E + medroxyprogesterone acetate (MPA) or E + MPA + human chorionic gonadotropin (hCG)). Spheroid attachment to E/MPA treated pHEEC prepared from fertile women or those with idiopathic infertility tested.

MAIN OUTCOME MEASURE

Firmly attached spheroids counted after co-culture for 6 h. Outgrowth was determined by quantitation of area covered by spheroid after firm adhesion.

RESULTS

Functional adhesion of TS to two endometrial epithelial cell lines, Ishikawa and ECC-1 cells, was hormonally responsive, with adhesion/outgrowth increased by E/MPA (ECC-1; p < 0.01, Ishikawa; p < 0.01) and E/MPA/hCG (ECC-1; p < 0.001, Ishikawa p < 0.01) versus E alone. The same pattern of hormone responsiveness was observed in pHEEC obtained from fertile women (E vs, E/MPA; p < 0.01, E vs. E/MPA/hCG; p < 0.001). TS adhered to 85% of pHEEC obtained from fertile women (11/13) and 11% of pHEEC obtained from women with unexplained infertility (2/18, p < 0.001).

CONCLUSION

This new model of "embryo" implantation largely discriminates between endometrial epithelial cells obtained from fertile vs. infertile women based on adhesion; this holds potential as an in vitro "diagnostic" tool of endometrial infertility.

Layered double hydroxide eliminate embryotoxicity of chemotherapeutic drug through BMP-SMAD signaling pathway

Recent studies indicate that exogenous chemotherapy agents can cross the placenta barrier and cause fetal toxicity, while there exists barely alternative therapy for pregnant cancer patients. Here, we show a robust protective effect of layered double hydroxide (LDH) against etoposide (VP16) induced in vitro mouse embryonic stem cells (mESCs) toxicity and in vivo embryo developmental disorders. The nano-composite system (L-V) abrogated the original VP16 generated mitochondrial mediated mESCs toxicity totally, surprisingly maintained the pluripotency without leukemia inhibitory factor (LIF) and prevented the down-regulation of ectoderm marker expression during spontaneous embryoid bodies differentiation. Fetal growth retardation, the related placenta and skeletal structural abnormalities and long-term toxicity in the offspring were generated when pregnant mice exposed to VP16, while these detrimental effects were abolished when substituted with L-V. The different uterine drug accumulation of VP16 and L-V contributed to partly cause for the functional variation. And further transcriptome analysis confirmed developmental related BMP4-SMAD6 signaling pathway is of crucial importance. Our study revealed the devastating effects of VP16 on embryonic development and the toxicity-relieve method using nano-carrier system, which will provide important guidance for clinical application of LDH as alternative therapeutic system with minimal side effects for pregnant women diagnosed with cancer.

Hyaluronic acid and epidermal growth factor improved the bovine embryo quality by regulating the DNA methylation and expression patterns of the focal adhesion pathway

Focal adhesion pathway is one of the key molecular pathways affected by suboptimal culture conditions during embryonic development. The epidermal growth factor (EGF) and hyaluronic acid (HA) are believed to be involved in the focal adhesion pathway function by regulating the adherence of the molecules to the extracellular matrix. However, regulatory and molecular mechanisms through which the EGF and HA could influence the embryo development is not clear. Therefore, this study aimed to investigate the effect of continued or stage specific supplementation of EGF and/or HA on the developmental competence and quality of bovine preimplantation embryos and the subsequent consequences on the expression and DNA methylation patterns of genes involved in the focal adhesion pathway. The results revealed that, the supplementation of EGF or HA from zygote to the blastocysts stage reduced the level of reactive oxygen species and increased hatching rate after thawing. On the other hand, HA decreased the apoptotic nuclei and increased blastocyst compared to EGF supplemented group. Gene expression and DNA methylation analysis in the resulting blastocysts indicated that, combined supplementation of EGF and HA increased the expression of genes involved in focal adhesion pathway while supplementation of EGF, HA or a combination of EGF and HA during the entire preimplantation period changed the DNA methylation patterns of genes involved in focal adhesion pathway. On the other hand, blastocysts developed in culture media supplemented with EGF + HA until the 16-cell stage exhibited higher expression level of genes involved in focal adhesion pathway compared to those supplemented after the 16-cell stage. Conversely, the DNA methylation level of candidate genes was increased in the blastocysts obtained from embryos cultured in media supplemented with EGF + HA after 16-cell stage. In conclusion, supplementation of bovine embryos with EGF and/or HA during the entire preimplantation period or in a stage specific manner altered the DNA methylation and expression patterns of candidate genes involved in the focal adhesion pathway which was in turn associated with the observed embryonic developmental competence and quality.

Melatonin enhances porcine embryo development via the Nrf2/ARE signaling pathway

Oxidative stress (OS) is a major problem during in vitro culture of embryos. Numerous studies have shown that melatonin, which is known to have antioxidant properties, prevents the occurrence of OS in embryos. However, the molecular mechanisms by which melatonin prevents OS in embryos are still unclear. The present study suggests a possible involvement of the nuclear factor erythroid 2-related factor 2/antioxidant-responsive element (Nrf2/ARE) signaling pathway, which is one of the prominent signals for OS prevention through Nrf2 activation, connecting melatonin, OS prevention and porcine embryonic development. The aim of this study was to investigate the effects of melatonin (10-7 M) on porcine embryonic development via the Nrf2/ARE signaling pathway; brusatol (50 nM; Nrf2 specific inhibitor) was used to validate the mechanism. Treatment of porcine embryo with melatonin significantly increased formation rates of blastocysts and their total cell numbers and also upregulated the expression of Nrf2/ARE signaling and apoptosis-related genes (MT2, NRF2, UCHL, HO-1, SOD1 and BCL-2). Furthermore, the expression of proteins (NRF2 and MT2) was also upregulated in the melatonin-treated group. Concomitantly, brusatol significantly inhibited these effects, upregulating the expression of KEAP1 and BAX, including the expression level of KEAP1 protein. These results provide evidences that melatonin prevents OS through Nrf2/ARE signaling pathway in porcine in vitro fertilization -derived embryos.

ProTAME Arrest in Mammalian Oocytes and Embryos Does Not Require Spindle Assembly Checkpoint Activity

In both mitosis and meiosis, metaphase to anaphase transition requires the activity of a ubiquitin ligase known as anaphase promoting complex/cyclosome (APC/C). The activation of APC/C in metaphase is under the control of the checkpoint mechanism, called the spindle assembly checkpoint (SAC), which monitors the correct attachment of all kinetochores to the spindle. It has been shown previously in somatic cells that exposure to a small molecule inhibitor, prodrug tosyl-l-arginine methyl ester (proTAME), resulted in cell cycle arrest in metaphase, with low APC/C activity. Interestingly, some reports have also suggested that the activity of SAC is required for this arrest. We focused on the characterization of proTAME inhibition of cell cycle progression in mammalian oocytes and embryos. Our results show that mammalian oocytes and early cleavage embryos show dose-dependent metaphase arrest after exposure to proTAME. However, in comparison to the somatic cells, we show here that the proTAME-induced arrest in these cells does not require SAC activity. Our results revealed important differences between mammalian oocytes and early embryos and somatic cells in their requirements of SAC for APC/C inhibition. In comparison to the somatic cells, oocytes and embryos show much higher frequency of aneuploidy. Our results are therefore important for understanding chromosome segregation control mechanisms, which might contribute to the premature termination of development or severe developmental and mental disorders of newborns.

Growth hormone co-treatment on controlled ovarian stimulation in normal ovarian response women can improve embryo quality

To investigate the clinical efficacy of growth hormone (GH) in normal response patients with poor embryo quality in previous in vitro fertilization cycles. A total of 1562 infertile women were enrolled in this matched case-control study: 781 women were treated with GH (study group), whereas 781 matched patients were treated without GH (control group). GH was administered by a daily subcutaneous injection of 2 or 4 IU started from either D2 of the previous cycle (6 weeks GH pretreatment) or the initial day of controlled ovarian stimulation (2 weeks GH pretreatment) until hCG trigger. The study group was further divided into four subgroups: 2 IU-6 weeks GH pretreatment, 4 IU-6 weeks GH pretreatment, 2 IU-2 weeks GH pretreatment, and 2 IU-4 weeks GH pretreatment. Patients receiving GH showed significantly lower Gn dosage. The total number of oocytes retrieved, embryos formed, endometrial thickness on hCG day were significantly higher with GH. 2PN rate and high-quality embryo rate were lower in the GH group. However, GH increased clinical pregnancy rate with significant difference. 4 IU-6 weeks GH pretreatment showed lowest duration of Gn and highest clinical pregnancy rate compared with other three groups. Number of transferred embryos was confounding factor both in univariate and multivariate analysis. Our study showed that co-treatment with GH in patients with normal ovarian response could increase pregnancy rate.

Mortality, teratogenicity and growth inhibition of three glyphosate formulations using Frog Embryo Teratogenesis Assay-Xenopus

Ample evidence around the world exists suggesting a link between exposure to glyphosate, toxicity and perturbed physiological functions in non-target organisms. Although glyphosate formulations are widely used for weed and alien plant management, their ecotoxicological information remain scanty. Using the 96-hour Frog Embryo Teratogenesis Assay-Xenopus protocol, embryotoxicity and teratogenicity of three glyphosate-based formulations were assessed. Embryos of Xenopus laevis were exposed to Roundup, Kilo Max and Enviro Glyphosate at concentration of 0.3-1.3, 130-280 and 320-560 mg acid equivalent (a.e.)/L respectively. The results showed Roundup to be more toxic than the other formulations with a 96-hour LC50 of 1.05 mg a.e/L. compared with 207 mg a.e./L, and 466 mg a.e./L for Kilo Max and Enviro Glyphosate respectively. Although, both Roundup and Kilo Max formulations show inhibition on growth of the embryo-larva (P ˂ .05), the minimum concentration inhibiting growth ratios of the three formulations was >0.30 baseline, indicating no significant growth inhibiting effect in the formulations. For teratogenicity, Roundup and Enviro Glyphosate formulations exhibited increasing teratogenic traces, with the teratogenic index at 1.7 and 1.6 respectively. Kilo Max formulation shows low teratogenicity with the teratogenic index at 1.4. Characteristic malformation induced by these formulations included generalized edema, cardiac and abdominal edema, improper gut formation and axial malformations. This study confirms that these formulations could be a potential physiological and ecological health disruptor, particularly concerning teratogenicity and growth disruption. Further studies to characterize the contributions of their surfactants will be invaluable.

Sodium butyrate interrupts the maturation of oocytes and enhances the development of preimplantation embryos

Histone acetylation is one of the most important posttranslational modifications that contribute to transcriptional initiation and chromatin remodeling. In the present study, we aimed to investigate the effect of sodium butyrate (NaBu), a natural histone deacetylase inhibitor (HDACi), on the maturation of oocytes, preimplantation embryonic development, and expression of important developmental genes. The results indicated that NaBu decreased the rates of GVBD and the first polar body extrusion (PBE) in vitro in a dose-dependent manner. Meanwhile, NaBu treatment led to an abnormality in the spindle apparatus in oocytes in MI. However, the ratio of phosphor-extracellular signal-regulated kinases (p-ERK)/ERK significantly decreased in oocytes treated with 2.0 mM NaBu for 8 h. Furthermore, NaBu treatment at 2.0 mM improved the quality of embryos and the mRNA expression levels of important developmental genes such as HDAC1, Sox2, and Pou5f1. These data suggest that although a high concentration NaBu will impede the meiosis of oocytes, 2.0 mM NaBu will promote the development of embryos in vitro. Further investigation is needed to clarify the direct/indirect effects of NaBu on the regulation of important developmental genes and their subsequent impacts on full-term development in mammals.

F-box protein FBXO30 mediates retinoic acid receptor γ ubiquitination and regulates BMP signaling in neural tube defects

Retinoic acid (RA), an active derivative of vitamin A, is critical for the neural system development. During the neural development, the RA/RA receptor (RAR) pathway suppresses BMP signaling-mediated proliferation and differentiation of neural progenitor cells. However, how the stability of RAR is regulated during neural system development and how BMP pathway genes expression in neural tissue from human fetuses affected with neural tube defects (NTDs) remain elusive. Here, we report that FBXO30 acts as an E3 ubiquitin ligase and targets RARγ for ubiquitination and proteasomal degradation. In this way, FBXO30 positively regulates BMP signaling in mammalian cells. Moreover, RA treatment leads to suppression of BMP signaling by reducing the level of FBXO30 in mammalian cells and in mouse embryos with NTDs. In samples from human NTDs with high levels of retinol, downregulation of BMP target genes was observed, along with aberrant FBXO30 levels. Collectively, our results demonstrate that RARγ levels are controlled by FBXO30-mediated ubiquitination and that FBXO30 is a key regulator of BMP signaling. Furthermore, we suggest a novel mechanism by which high-retinol levels affect the level of FBXO30, which antagonizes BMP signaling during early stage development.

The evaluation of embryotoxicity of Ligusticum chuanxiong on mice and embryonic stem cells

ETHNOPHARMACOLOGICAL RELEVANCE

Chuanxiong (Chuanxiong Rhizoma, CR), the dried rhizome of Ligusticum chuanxiong Hort, has been used during pregnancy for more than 2000 years. However, the embryotoxicity of CR was not evaluated so far. The purpose of this study was to examine the safety and rational use of CR during pregnancy on mice and mouse embryonic stem cell (ES), and to explore the mechanism of embryotoxicity.

AIM OF THE STUDY

This study was carried out to evaluate embryotoxicity of CR decoction in vivo and in vitro, and to explore the mechanism of embryotoxicity from the perspective of bone metabolism.

MATERIALS AND METHODS

In animal experiments, pregnant mice were randomly assigned into 5 groups, i.e. mice were orally treated with CR decoction at dosages of 0 (distilled water, as negative controls), 2, 8, 32 g/kg/d (low, medium and high-dose group), and vitamin A (as positive controls), respectively. Maternal and embryo-fetal parameters were registered after cesarean section. The fetal skeletal development was further assessed with the alizarin red S and Hematoxylin-Eosin staining (H&E staining) and fluorescent imaging. Meanwhile, the mouse embryonic stem cell test model (EST model) was established to objectively evaluate the toxicity of CR on the embryo development. The median inhibitory proliferation values (IC₅₀) for both the mouse embryonic stem cell D3 (ES) and mouse embryonic fibroblast 3T3 (3T3) were detected with MTT assays. After removal of inhibiting factor (LIF), mouse embryonic stem cells spontaneously differentiated into cardiomyocytes, the expression of specific myosin heavy chain gene (β-MHC) contained in cardiomyocytes were detected by q-PCR quantitative analysis, and median inhibitory differentiation concentration (ID₅₀) of ES was obtained. The development toxicity calculation formula was used to determine the embryotoxicity grade of CR decoction. finally, based on the successful induction of osteoblasts, the molecular mechanism of CR embryotoxicity was preliminarily studied based on BMP-Smads signal pathway.

RESULTS

Compared with the negative control group, high, medium, and low doses of CR decoction had no significant effect on the maternal body weight and uterine weight (P > 0.05), as well as on the maternal liver, heart, and kidneys. The observation results showed that high dose of CR decoction significantly increase the number of absorbed fetuses (P < 0.05). The EST model was successfully established, the IC₅₀ 3T3, IC₅₀ ES and ID₅₀ ES of CR were 9.39 mg/mL, 18.78 mg/mL, and 10.20 mg/mL, respectively. CR was classified as weak embryonic development toxicity by the EST linear discriminant formula. Meanwhile, osteoblasts were successfully induced in vitro, the relative expression levels of BMP2, BMPR2, Smad1, and Smad5 were down-regulated in varying degrees after 3, 6, and 9 days of treatment with different concentration gradients of CR decoction.

CONCLUSIONS

Combining in vivo and in vitro experiments, CR showed a potential embryotoxicity. The mechanism of embryotoxicity may be related to inhibiting the expression of key genes in the BMP-SMADs signaling pathway. In the clinical application, the normal dosage of CR is safe to a certain extent. However, when the dosage is too high (160 g/60 kg/d), there may be a risk of embryotoxicity.

Developmental exposure to a very low dose of bisphenol A induces persistent islet insulin hypersecretion in Fischer 344 rat offspring

BACKGROUND

In children with obesity, accentuated insulin secretion has been coupled with development of type 2 diabetes mellitus (T2DM). Bisphenol A (BPA) is a chemical with endocrine- and metabolism-disrupting properties which can be measured in a majority of the population. Exposure to BPA has been associated with the development of metabolic diseases including T2DM.

OBJECTIVE

The aim of this study was to investigate if exposure early in life to an environmentally relevant low dose of BPA causes insulin hypersecretion in rat offspring.

METHODS

Pregnant Fischer 344 rats were exposed to 0.5 (BPA0.5) or 50 (BPA50) µg BPA/kg BW/day via drinking water from gestational day 3.5 until postnatal day 22. Pancreata from dams and 5- and 52-week-old offspring were procured and islets were isolated by collagenase digestion. Glucose-stimulated insulin secretion and insulin content in the islets were determined by ELISA.

RESULTS

Basal (5.5 mM glucose) islet insulin secretion was not affected by BPA exposure. However, stimulated (11 mM glucose) insulin secretion was enhanced by about 50% in islets isolated from BPA0.5-exposed 5- and 52-week-old female and male offspring and by 80% in islets from dams, compared with control. In contrast, the higher dose, BPA50, reduced stimulated insulin secretion by 40% in both 5- and 52-week-old female and male offspring and dams, compared with control.

CONCLUSION

A BPA intake 8 times lower than the European Food Safety Authority's (EFSA's) current tolerable daily intake (TDI) of 4 µg/kg BW/day of BPA delivered via drinking water during gestation and early development causes islet insulin hypersecretion in rat offspring up to one year after exposure. The effects of BPA exposure on the endocrine pancreas may promote the development of metabolic disease including T2DM.

Validation of the Rat Limb Bud Micromass Test in the International ECVAM Validation Study on Three In Vitro Embryotoxicity Tests

A detailed report is presented on the performance of the rat limb bud micromass (MM) test in a European Centre for the Evaluation of Alternative Methods (ECVAM)-sponsored formal validation study on three in vitro tests for embryotoxicity. Twenty coded test chemicals, classified as non-embryotoxic, weakly embryotoxic or strongly embryotoxic on the basis of their in vivo effects on animals and/or humans, were tested in four laboratories. The outcome showed that the MM test is an experimentally validated test, which holds promise for use for identifying strongly embryotoxic chemicals, but which needs to be improved before it can be recommended for use for regulatory purposes.