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Testing for developmental toxicity according to the current regulatory guidelines requires large numbers of animals, making these tests very resource intensive, time-consuming, and ethically debatable. Over the past decades, several alternative in vitro assays have been developed, but these often suffered from low predictability and the inability to provide a mechanistic understanding of developmental toxicity.To identify embryotoxic compounds, we developed a human induced pluripotent stem cells (hiPSCs)-based biomarker assay. The assay is based on the differentiation of hiPSCs into functional cardiomyocytes and hepatocytes. Proper stem cell differentiation is investigated by morphological profiling and assessment of time-dependent expression patterns of cell-specific biomarkers. In this system, a decrease in the expression of the biomarker genes and morphology disruption of the differentiated cells following compound treatment indicated teratogenicity.The hiPSCs-based biomarker assay was validated with 21 well-established in vivo animal teratogenic and non-teratogenic compounds during cardiomyocyte and hepatocyte differentiation. The in vivo teratogenic compounds (e.g., thalidomide and valproic acid) markedly disrupted morphology, functionality, and the expression pattern of the biomarker genes in either one or both cell types. Non-teratogenic chemicals generally had no effect on the morphology of differentiated cells, nor on the expression of the biomarker genes. Compared to the in vivo classification, the assay achieved high accuracy (91%), sensitivity (91%), and specificity (90%).The assay, which we named ReproTracker®, is a state-of-the-art in vitro method that can identify the teratogenicity potential of new pharmaceuticals and chemicals and signify the outcome of in vivo test systems.

Background Cannabinoids including cannabidiol have recognized genotoxic activities but their significance has not been studied broadly epidemiologically across the teratological spectrum. We examined these issues including contextual space-time relationships and formal causal inferential analysis in USA. Methods State congenital anomaly (CA) rate (CAR) data was taken from the annual reports of the National Birth Defects Prevention Network 2001–2005 to 2011–2015. Substance abuse rates were from the National Survey of Drug Use and Health a nationally representative longitudinal survey of the non-institutionalized US population with 74.1% response rate. Drugs examined were cigarettes, monthly and binge alcohol, monthly cannabis and analgesic and cocaine abuse. Early termination of pregnancy for abortion (ETOPFA) rates were taken from the published literature. Cannabinoid concentrations were from Drug Enforcement Agency. Ethnicity and income data were from the US Census Bureau. Inverse probability weighted (IPW) regressions and geotemporospatial regressions conducted for selected CAs. Results Data on 18,328,529 births from an aggregated population of 2,377,483,589 for mid-year analyses 2005–2013 comprehending 12,611 CARs for 62 CAs was assembled and ETOPFA-corrected (ETOPFACAR) where appropriate. E-Values for ETOPFACARs by substance trends were elevated for THC (40 CAs), cannabis (35 CAs), tobacco (11 CAs), cannabidiol (8 CAs), monthly alcohol (5 CAs) and binge alcohol (2 CAs) with minimum E-Values descending from 16.55, 1.55x107, 555.10, 7.53x1019, 9.30 and 32.98. Cardiovascular, gastrointestinal, chromosomal, limb reductions, urinary, face and body wall CAs particularly affected. Highest v. lowest substance use quintile CAR prevalence ratios 2.84 (95%C.I. 2.44, 3.31), 4.85 (4.08, 5.77) and 1.92 (1.63, 2.27) and attributable fraction in exposed 0.28 (0.27, 0.28), 0.57 (0.51, 0.62) and 0.47 (0.38, 0.55) for tobacco, cannabis and cannabidiol. Small intestinal stenosis or atresia and obstructive genitourinary defect were studied in detail in lagged IPW pseudo-randomized causal regressions and spatiotemporal models confirmed the causal role of cannabinoids. Spatiotemporal predictive modelling demonstrated strongly sigmoidal non-linear cannabidiol dose-response power-function relationships (P = 2.83x10−60 and 1.61x10−71 respectively). Conclusions Data implicate cannabinoids including cannabidiol in a diverse spectrum of heritable CAs. Sigmoidal non-linear dose-response relationships are of grave concern. These transgenerational genotoxic, epigenotoxic, chromosomal-toxic putatively causal teratogenic effects strongly indicate tight restrictions on community cannabinoid penetration.

Nicotinamide adenine dinucleotide (NAD+) depletion is associated with numerous diseases in humans. Recently it was revealed that genetic blockage of the NAD+ synthesis pathway in humans causes birth defects in multiple organ systems and miscarriage. Additionally, mice with NAD+ deficiency created through dietary restriction of tryptophan and vitamin B3 were shown to have congenital anomalies affecting virtually every organ system along with miscarriage. Perturbations in NAD+/NADH affect mechanisms of teratogenesis presented by Wilson and others, including genetic alterations, altered energy sources, and lack of precursors and substrates needed for biosynthesis.Medical literature was evaluated to demonstrate how perturbations in NAD+/NADH affect mechanisms of teratogenesis. In addition, literature describing several different teratogens of various types (infectious, physical, maternal health factors, drugs) was reviewed showing the impact of these teratogens on NAD+ and NAD+/NADH ratios.Many teratogens affect NAD+ by altering its metabolism, decreasing its intracellular availability, or decreasing its production, which in turn is a plausible mechanism for the creation of birth defects.Looking at teratogens through the lens of their impact on NAD+ could provide valuable insight into the mechanism by which some teratogens cause birth defects and miscarriage.

BACKGROUNDThe function of the gestational sac (GS) and the placenta in the closely related processes of embryogenesis and teratogenicity in the first trimester has been minimally described. The prevailing assumption is that direct teratogenic effects are mediated by the critical extraembryonic organ, the placenta, which either blocks or transfers exposures to the foetus. Placental transfer is a dominant mechanism, but there are other paradigms by which the placenta can mediate teratogenic effects. Knowledge of these paradigms and first trimester human developmental biology can be useful to the epidemiologist in the conduct of biomarker-based studies of both maternal and child health.OBJECTIVE AND RATIONALEOur aim is to provide a causal framework for modelling the teratogenic effects of first trimester exposures on child health outcomes mediated by the GS and placenta using biomarker data collected in the first trimester. We initially present first trimester human developmental biology for the sake of informing and strengthening epidemiologic approaches. We then propose analytic approaches of modelling placental mechanisms by way of causal diagrams using classical non-embryolethal teratogens (diethylstilboestrol [DES], folic acid deficiency and cytomegalovirus [CMV]) as illustrative examples. We extend this framework to two chronic exposures of particular current interest, phthalates and maternal adiposity.SEARCH METHODSInformation on teratogens was identified by a non-systematic, narrative review. For each teratogen, we included papers that answered the five following questions: (i) why were these exposures declared teratogens? (ii) is there a consensus on biologic mechanism? (iii) is there reported evidence of a placental mechanism? (iv) can we construct a theoretical model of a placental mechanism? and (v) can this knowledge inform future work on measurement and modelling of placental-foetal teratogenesis? We prioritized literature specific to human development, the organogenesis window in the first trimester and non-embryolethal mechanisms.OUTCOMESAs a result of our review of the literature on five exposures considered harmful in the first trimester, we developed four analytic strategies to address first trimester placental mechanisms in birth cohort studies: placental transfer and direct effects on the foetus (DES and maternal adiposity), indirect effects through targeted placental molecular pathways (DES and phthalates), pre-placental effects through disruptions in embryonic and extraembryonic tissue layer differentiation (folic acid deficiency), and multi-step mechanisms that involve maternal, placental and foetal immune function and inflammation (DES and CMV).WIDER IMPLICATIONSThe significance of this review is to offer a causal approach to classify the large number of potentially harmful exposures in pregnancy when the exposure occurs in the first trimester. Our review will facilitate future research by advancing knowledge of the first trimester mechanisms necessary for researchers to effectively associate environmental exposures with child health outcomes.

All-trans retinoic acid (ATRA), the biologically active form of vitamin A, is instrumental in regulating the patterning and specification of the vertebrate embryo. Various animal models demonstrate adverse developmental phenotypes following experimental retinoid depletion or excess during pregnancy. Windows of vulnerability for altered skeletal patterning coincide with early specification of the body plan (gastrulation) and regional specification of precursor cell populations forming the facial skeleton (cranial neural crest), vertebral column (somites), and limbs (lateral plate mesoderm) during organogenesis. A common theme in physiological roles of ATRA signaling is mutual antagonism with FGF signaling. Consequences of genetic errors or environmental disruption of retinoid signaling include stage- and region-specific homeotic transformations to severe deficiencies for various skeletal elements. This review derives from an annex in Detailed Review Paper (DRP) of the OECD Test Guidelines Programme (Project 4.97) to support recommendations regarding assay development for the retinoid system and the use of resulting data in a regulatory context for developmental and reproductive toxicity (DART) testing.

Organogenesis is a complex process that can be disrupted by embryonic exposure to teratogens or mutation-induced alterations in signalling pathways, both of which result in organ mispatterning. Building on prior work in Xenopus laevis that showed that increased HCN2 ion channel activity rescues nicotine-induced brain and eye morphogenesis, we demonstrate much broader HCN2-based rescue of organ patterning defects. Induced HCN2 expression in both local or distant tissues can rescue CNS (brain and eye) as well as non-CNS (heart and gut) organ defects induced by three different teratogenic conditions: nicotine exposure, ethanol exposure or aberrant Notch protein. Rescue can also be induced by small-molecule HCN2 channel activators, even with delayed treatment initiation. Our results suggest that HCN2 (likely mediated by bioelectric signals) can be an effective regulator of organogenesis from all three germ layers (ectoderm, mesoderm and endoderm) and reveal non-cell-autonomous influences on organ formation that work at a considerable distance during embryonic development. These results suggest molecular bioelectric strategies for repair that could be explored in the future for regenerative medicine.

The use of Δ8THC is increasing at present across the USA in association with widespread cannabis legalization and the common notion that it is “legal weed”. As genotoxic actions have been described for many cannabinoids, we studied the cancer epidemiology of Δ8THC. Data on 34 cancer types was from the Centers for Disease Control Atlanta Georgia, substance abuse data from the Substance Abuse and Mental Health Services Administration, ethnicity and income data from the U.S. Census Bureau, and cannabinoid concentration data from the Drug Enforcement Agency, were combined and processed in R. Eight cancers (corpus uteri, liver, gastric cardia, breast and post-menopausal breast, anorectum, pancreas, and thyroid) were related to Δ8THC exposure on bivariate testing, and 18 (additionally, stomach, Hodgkins, and Non-Hodgkins lymphomas, ovary, cervix uteri, gall bladder, oropharynx, bladder, lung, esophagus, colorectal cancer, and all cancers (excluding non-melanoma skin cancer)) demonstrated positive average marginal effects on fully adjusted inverse probability weighted interactive panel regression. Many minimum E-Values (mEVs) were infinite. p-values rose from 8.04 × 10−78. Marginal effect calculations revealed that 18 Δ8THC-related cancers are predicted to lead to a further 8.58 cases/100,000 compared to 7.93 for alcoholism and −8.48 for tobacco. Results indicate that between 8 and 20/34 cancer types were associated with Δ8THC exposure, with very high effect sizes (mEVs) and marginal effects after adjustment exceeding tobacco and alcohol, fulfilling the epidemiological criteria of causality and suggesting a cannabinoid class effect. The inclusion of pediatric leukemias and testicular cancer herein demonstrates heritable malignant teratogenesis.

Human induced pluripotent stem cells (hiPSC) were used to develop an assay format that may deliver information on teratogenicity of drugs. A human pluripotent stem cell scorecard panel was used to monitor the expression of 96 marker genes that are indicative of the stem cell state or differentiation into the ectoderm, mesoderm and endoderm lineages. We selected a human episomal iPS cell line for the assay based on karyotype stability, initial pluripotency, differentiation capacity and overall gene expression variability. The assay is based on embryoid body formation and was developed to be simply automated. In this proof of concept study, we used eight reference compounds (valproic acid, all-trans-retinoic acid, thalidomide, methotrexate, hydroxyurea, ascorbic acid, penicillin G and ibuprofen) to test the technical performance of the assay (readout stability) in concentration-response and time-course experiments. We also found that each compound affected marker gene expression in a different way. Various forms of data analysis identified 19 out of 96 early developmental genes as potential predictive markers for teratogenicity. Machine-learning models were run to exemplify how the assay will be developed further. The preliminary results from these analyses suggest that the assay could be suitable for the pre-screening of candidate pharmaceutical compounds. The approach presented here points a way towards development of a human cell-based assay that could replace the murine EST currently used to screen for early indications of potential teratogenicity of drug candidates. published

AimTo systematically identify studies of implementing risk management measures when prescribing teratogenic medicines for women of childbearing age and studies reporting risk perceptions of teratogenic medications.MethodsMEDLINE, CINAHL, Scopus, EMBASE, and International Pharmaceutical Abstracts were searched. Studies were included in the risk management section if they reported any of the following risk management measures: teratogenic counseling, contraceptive counseling, pregnancy testing before starting treatment, pregnancy testing during treatment, use of contraception before starting treatment, and use of contraception during treatment. Studies were included in the perceptions section if they reported perceived teratogenic risk as numerical value.ResultsFifty‐five studies were included in the risk management section and seven studies were included in the perceptions sections. Prevalence of risk management measures varied as follows: teratogenic counseling (9.5%–99.3%), contraceptive counseling (6.1%–98%), pregnancy testing before starting treatment (0%–95.1%), pregnancy testing during treatment (12.7%–100%), contraception use before starting treatment (15.7%–94%), and contraception use during treatment (1.7%–100%). A proper estimation of the teratogenic risk was reported for thalidomide (by general practitioners and obstetric/gynecologists), for etretinate (by pregnant women), and for misoprostol (by pregnant and nonpregnant women). An under‐estimation was reported for warfarin and retinoids (by general practitioners and obstetric/gynecologists). And over‐estimation was reported for thalidomide, valproate, lithium, isotretinoin, phenytoin, warfarin and etretinate by different populations.ConclusionConsiderable variation in the implementation of risk management measures when prescribing teratogenic medicines to women of childbearing age is reported in the literature. A common tendency to over‐estimate the risk of teratogenic medications was evident.

Many xenobiotics in the environment affect the human body in various ways. Among those xenobiotics, lithium chloride (Li, LiCl) and monosodium glutamate (L-glutamic acid monosodium salt, MSG) compounds affect the crucial processes of stem cell differentiation, cell proliferation, developmental gene expression, and overall development in animals. In this study, we aimed to examine the developmental effects of exposure to flavor enhancer MSG and LiCI medicament on Xenopus embryos using the frog embryo teratogenesis assay of Xenopus test. To this purpose, Xenopus laevis embryos were exposed to four different concentrations of MSG (120, 500, 750, 1000 mg/dL) and Li (0.02 g/L) alone and in combinations for a period of 96 h, and then normal, abnormal, and death ratios were determined in all exposure groups. Besides, length values of all groups and membrane potentials of fertilized and non-fertilized oocyte groups treated with 120- and 500-mg/dL MSG doses and 0.02-g/L LiCI dose were measured. Treatment with ADI (acceptable daily intake) dose of MSG alone did not lead to a substantial effect on the development of Xenopus laevis embryos. But, exposure to daily doses exceeding the ADI level (500, 750, 1000 mg/dL) caused significant harmful effects. Besides, Li-involving treatments caused dramatic deleterious effects on embryo development. MSG attenuated harmful effects of Li in MSG+Li combined treatments. Membrane potentials of non-fertilized oocytes and fertilized eggs were significantly changed in all groups that their membrane potentials were measured. Extrapolating these results into humans require similarly designed studies conducted on human embryos.

There is a great need for novel in vitro methods to predict human developmental toxicity to comply with the 3R principles and to improve human safety. Human-induced pluripotent stem cells (hiPSC) are ideal for the development of such methods, because they are easy to retrieve by conversion of adult somatic cells and can differentiate into most cell types of the body. Advanced three-dimensional (3D) cultures of these cells, so-called embryoid bodies (EBs), moreover mimic the early developing embryo. We took advantage of this to develop a novel human toxicity assay to predict chemically induced developmental toxicity, which we termed the PluriBeat assay. We employed three different hiPSC lines from male and female donors and a robust microtiter plate-based method to produce EBs. We differentiated the cells into cardiomyocytes and introduced a scoring system for a quantitative readout of the assay—cardiomyocyte contractions in the EBs observed on day 7. Finally, we tested the three compounds thalidomide (2.3–36 µM), valproic acid (25–300 µM), and epoxiconazole (1.3–20 µM) on beating and size of the EBs. We were able to detect the human-specific teratogenicity of thalidomide and found the rodent toxicant epoxiconazole as more potent than thalidomide in our assay. We conclude that the PluriBeat assay is a novel method for predicting chemicals’ adverse effects on embryonic development. Electronic supplementary material The online version of this article (10.1007/s00204-020-02856-6) contains supplementary material, which is available to authorized users.

In vitro human induced pluripotent stem (iPS) cells testing (iPST) to assess developmental toxicity, e.g., the induction of malformation or dysfunction, was developed by modifying a mouse embryonic stem cell test (EST), a promising animal-free approach. The iPST evaluates the potential risks and types of drugs-induced developmental toxicity in humans by assessing three endpoints: the inhibitory effects of the drug on the cardiac differentiation of iPS cells and on the proliferation/survival of iPS cells and human fibroblasts. In the present study, the potential developmental toxicity of drugs was divided into three classes (1: non-developmentally toxic, 2: weakly developmentally toxic and 3: strongly developmentally toxic) according to the EST criteria. In addition, the type of developmental toxicity of drugs was grouped into three types (1: non-effective, 2: embryotoxic [inducing growth retardation/dysfunction]/deadly or 3: teratogenic [inducing malformation]/deadly) by comparing the three endpoints. The present study was intended to validate the clinical predictability of the iPST. The traditionally developmentally toxic drugs of aminopterin, methotrexate, all-trans-retinoic acid, thalidomide, tetracycline, lithium, phenytoin, 5-fluorouracil, warfarin and valproate were designated as class 2 or 3 according to the EST criteria, and their developmental toxicity was type 3. The non-developmentally toxic drugs of ascorbic acid, saccharin, isoniazid and penicillin G were designated as class 1, and ascorbic acid, saccharin and isoniazid were grouped as type 1 while penicillin G was type 2 but not teratogenic. These results suggest that the iPST is useful for predicting the human developmental toxicity of drug candidates in a preclinical setting.

Aims P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are efflux transporters expressed in the placenta, limiting their substrates from reaching the foetus. Our aim was to investigate if concomitant prenatal exposure to several substrates or inhibitors of these transporters increases the risk of congenital anomalies. Methods The national Drugs and Pregnancy database, years 1996-2014, was utilized in this population-based birth cohort study. In the database, the Medical Birth Register, the Register on Induced Abortions, the Malformation register and the Register on Reimbursed Drug Purchases have been linked. The University of Washington Metabolism and Transport Drug Interaction Database was used to identify substrates and inhibitors of P-gp and BCRP. We included singleton pregnancies ending in birth or elective termination of pregnancy due to foetal anomaly. Known teratogens were excluded. We identified women exposed 1 month before pregnancy or during the first trimester to P-gp/BCRP polytherapy (n = 21 186); P-gp/breast cancer resistance protein monotherapy (n = 97 906); non-P-gp/BCRP polytherapy (n = 78 636); and unexposed (n = 728 870). We investigated the association between the exposure groups and major congenital anomalies using logistic regression adjusting for several confounders. Results The prevalence of congenital anomalies was higher in the P-gp/BCRP polytherapy group (5.5%) compared to the P-gp/BCRP monotherapy (4.7%, OR 1.13; 95% CI 1.05-1.21), the non-P-gp/BCRP polytherapy (4.9%, OR 1.14; 95% CI 1.06-1.22), and to the unexposed groups (4.2%, OR 1.23; 95% CI 1.15-1.31). Conclusion The results suggest a role of placental transporter-mediated drug interactions in teratogenesis.

Pluripotent stem cells recapitulate many aspects of embryogenesis in vitro. Here, we established a novel culture system to differentiate human embryonic stem cell aggregates (HESCA), and evaluated its utility for teratogenicity assessment. Culture of HESCA with modulators of developmental signals induced morphogenetic and molecular changes associated with differentiation of the paraxial mesoderm and neuroectoderm. To examine impact of teratogenic exposures on HESCA differentiation, 18 compounds were tested, for which adequate information on in vivo plasma concentrations is available. HESCA treated with each compound were examined for gross morphology and transcript levels of 15 embryogenesis regulator genes. Significant alterations in the transcript levels were observed for 94% (15/16) of the teratogenic exposures within 5-fold margin, whereas no alteration was observed for 92% (11/12) of the non-teratogenic exposures. Our study demonstrates that transcriptional changes in HESCA serve as predictive indicator of teratogenicity in a manner comparable to in vivo exposure levels.

BACKGROUND This study aimed to survey the overall situation of birth defects (BDs) among citizens of Hangzhou, China, and the risk factors of different BD types. MATERIAL AND METHODS We collected the data of 4349 perinatal infants with BDs in Hangzhou. The potentially associated risk factors of BDs were recorded and logistic regression analysis was used to predict the high incidence of BDs. RESULTS Among all perinatal infants with BDs, there were 4105 (94.3%) single births, 225 (5.2%) twin births, and 10 (0.2%) multiple births. In clinical outcomes, there were 2477 (57.0%) live births, 1806 (41.5%) dead fetuses, and 11 (0.3%) stillbirths. Down syndrome ranked first, accounting for 30.7% of the total births, followed by cleft lip and polydactyly. Low family income, nulliparity, high parity, high education level, and taking contraceptives in early pregnancy were found to be risk factors of Down syndrome. Low parity, low education level, and pesticide exposure were found to be risk factors of cleft lip. For polydactyly, young age of the mother and a parity above 0 were identified as risk factors. CONCLUSIONS Different risks factors can influence BD development and potentially help to predict specific BD types, such as demographic features and harmful exposure in early pregnancy.

The exposure of organisms to the nanoparticulate is potentially hazardous, particularly when it occurs during embryogenesis. The effects of commercial SiO2NPs in early development were studied, using Xenopus laevis as a model to investigate their possible future employment by means of the Frog Embryo Teratogenesis Assay-Xenopus test (FETAX). The SiO2NPs did not change the survival but produced several abnormalities in developing embryos, in particular, the dorsal pigmentation, the cartilages of the head and branchial arches were modified; the encephalon, spinal cord and nerves are anomalous and the intestinal brush border show signs of suffering; these embryos are also bradycardic. In addition, the expression of genes involved in the early pathways of embryo development was modified. Treated embryos showed an increase of reactive oxygen species. This study suggests that SiO2NPs are toxic but non-lethal and showed potential teratogenic effects in Xenopus. The latter may be due to their cellular accumulation and/or to the effect caused by the interaction of SiO2NPs with cytoplasmic and/or nuclear components. ROS production could contribute to the observed effects. In conclusion, the data indicates that the use of SiO2NPs requires close attention and further studies to better clarify their activity in animals, including humans.

Prevention of prenatal exposures to teratogenic drugs is a significant clinical and public health concern. With the enactment of the US Food and Drug Administration Amendments Act in 2007, the US Food and Drug Administration has begun to require manufacturers to implement Risk Evaluation and Mitigation Strategies to prevent prenatal exposures. Among 12 risk evaluation and mitigation strategy drugs, several had predecessor risk mitigation plans (eg, isotretinoin) and some were newly required (eg, mycophenolate). Only a small proportion of teratogenic drugs are currently subject to Risk Evaluation and Mitigation Strategies, and the extent of prenatal exposure to the universe of teratogenic drugs compared with drugs subject to Risk Evaluation and Mitigation Strategies is unknown. Moreover, the effectiveness of such advanced risk mitigation programs in preventing prenatal exposure is not clear.This study aimed to characterize the epidemiology of prenatal exposures to definite and potential teratogens during the risk evaluation and mitigation strategy era.We constructed a time-series of pregnancies identified from a national private insurance claims database (IBM MarketScan) to estimate prenatal exposures to teratogenic drugs (2006-2017). Pregnancy outcomes, gestational age, and the onset of pregnancy were determined with previously validated algorithms. The Teratology Information Service and Clinical Pharmacology databases were used to identify drugs with definite (n=141) or potential (n=65) teratogenic effects, and drugs with debatable risks such as benzodiazepines, statins, tetracyclines, sex hormones, infertility treatments, and gonadotropin-releasing hormone analogs were excluded. We defined prenatal exposure as ≥1 prescription fill or medical encounter involving administration of drugs with a definite teratogenic risk (including 12 for which there is a "current or discontinued" risk evaluation and mitigation strategy) or a potential teratogenic risk. We evaluated secular trends and modeled the effects of age, preconception exposure, and state healthcare quality rankings on prenatal exposure, adjusting for demographic factors and clinical conditions.The cohort included 3,445,612 pregnancies (2,532,444 live deliveries). Prenatal exposures to definite teratogens decreased slightly during the study years from 1.86 to 1.24 per 100 pregnancies between 2006 and 2017, whereas exposure increased for potential teratogens from 3.40% to 5.33%. Prenatal exposure prevalences were higher during the first trimester and for pregnancies that ended in nonlive outcomes. Drugs subject to Risk Evaluation and Mitigation Strategies had low background utilization and contributed to a small proportion of prenatal exposures (15.1 per 100,000 pregnancies). We also observed fewer prenatal exposures to risk evaluation and mitigation strategy drugs among women of childbearing age who used these treatments (0.14% vs 0.36% for any definite teratogen). Age extremes and low state-level healthcare quality rankings were independent predictors of prenatal exposure.Fetuses in more than 1 in 16 pregnancies continued to be exposed to teratogenic drugs during the past decade. Drugs with Risk Evaluation and Mitigation Strategies imposed a small burden of prenatal exposure because of the low background utilization rates and lower pregnancy prevalence among women of childbearing age who used these drugs. Although the declining exposure rates to teratogenic drugs with definite risk are encouraging, the rising prenatal exposure to drugs with potential risk calls for more assessments. Future research is needed to elucidate the health outcomes of fetuses exposed to potential risk drugs, understand the effectiveness of risk evaluation and mitigation strategy programs, and prioritize teratogenic drugs for advanced risk mitigation.

Contamination of phthalate ester plasticizers threatens the wildlife as well as human health. To evaluate the developmental toxicity of commonly used phthalate esters and emerging alternatives, the frog embryo teratogenesis assay-Xenopus (FETAX) was conducted for dibutyl-phthalate (DBP), benzyl-butyl-phthalate (BBP), dioctyl-terephthalate (DOTP), di(2-propylheptyl)-phthalate (DPHP), diisononyl-phthalate (DINP), diisodecyl-phthalate (DIDP), diethyl hexyl cyclohexane (DEHCH), and diisononyl-cyclohexane-1,2-dicarboxylate (DINCH). The 96-hrs LC

The exposure of organisms to the nanoparticulate is potentially hazardous, particularly when it occurs during embryogenesis. The effects of commercial SiO

Prenatal alcohol exposure (PAE) can have immediate and long-lasting toxic and teratogenic effects on an individual’s development and health. As a toxicant, alcohol can lead to a variety of physical and neurological anomalies in the fetus that can lead to behavioral and other impairments which may last a lifetime. Recent studies have focused on identifying mechanisms that mediate the immediate teratogenic effects of alcohol on fetal development and mechanisms that facilitate the persistent toxic effects of alcohol on health and predisposition to disease later in life. This review focuses on the contribution of epigenetic modifications and intercellular transporters like extracellular vesicles to the toxicity of PAE and to immediate and long-term consequences on an individual’s health and risk of disease.

Congenital Zika Syndrome (CZS) occurs in up to 42% of individuals exposed to ZIKV prenatally. Deregulation in gene expression and protein levels of components of the p53 signaling pathway, such as p53 and MDM2, due to ZIKV infection has been reported. Here, we evaluate functional polymorphisms in genes of the p53 signaling pathway as risk factors to CZS. Forty children born with CZS and forty-eight children exposed to ZIKV, but born without congenital anomalies were included in this study. Gestational and sociodemographic information as well as the genotypic and allelic frequencies of functional polymorphisms in TP53, MDM2, MIR605 and LIF genes were compared between the two groups. We found children with CZS exposed predominantly in the first trimester and controls in the third trimester (pTP53 rs1042522, which is associated with a more potent p53-induced apoptosis (p=0.007). Our findings suggest that the TP53 rs1042522 polymorphism should be better investigate as a genetic risk factor for the development of lissencephaly in children with CZS.

Rubella or German measles is an infection caused by rubella virus (RV). Infection of children and adults is usually characterized by a mild exanthematous febrile illness. However, RV is a major cause of birth defects and fetal death following infection in pregnant women. RV is a teratogen and is a major cause of public health concern as there are more than 100,000 cases of congenital rubella syndrome (CRS) estimated to occur every year. Several lines of evidence in the field of molecular biology of RV have provided deeper insights into the teratogenesis process. The damage to the growing fetus in infected mothers is multifactorial, arising from a combination of cellular damage, as well as its effect on the dividing cells. This review focuses on the findings in the molecular biology of RV, with special emphasis on the mitochondrial, cytoskeleton and the gene expression changes. Further, the review addresses in detail, the role of apoptosis in the teratogenesis process.

STUDY QUESTION: Is there an association between maternal occupational exposure to solvents, pesticides and metals as assessed by expert-based assessment and congenital anomalies in the offspring? SUMMARY ANSWER: There is an association between maternal occupational exposure to solvents and congenital anomalies in the offspring, including neural tube defects, congenital heart defects and orofacial clefts. WHAT IS KNOWN ALREADY: One important environmental risk factor for development of congenital anomalies is maternal occupational exposure to chemicals in the workplace prior to and during pregnancy. A number of studies have assessed the association with often conflicting results, possibly due to different occupational exposure assessing methods. STUDY DESIGN, SIZE, DURATION: For this systematic review with meta-analysis, the search terms included maternal occupation, exposure, congenital anomalies and offspring. Electronic databases MEDLINE and EMBASE were searched for English studies up to October 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two reviewers independently screened all citations identified by the search. Case-control studies and cohort studies were included if (I) they reported on the association between maternal occupational exposure to solvents, pesticides or metals and congenital anomalies, and (II) assessment of occupational exposure was performed by experts. Data on study characteristics, confounders and odds ratios (ORs) were extracted from the included studies for four subgroups of congenital anomalies. Methodological quality was assessed using the Newcastle-Ottawa Scale. In the meta-analysis, random effects models were used to pool estimates. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 2806 titles and abstracts and 176 full text papers were screened. Finally, 28 studies met the selection criteria, and 27 studies could be included in the meta-analysis. Our meta-analysis showed that maternal occupational exposure to solvents was associated with neural tube defects (OR: 1.51, 95%CI: 1.09-2.09) and congenital heart defects (OR: 1.31, 95%CI:1.06-1.63) in the offspring. Also maternal occupational exposure to glycol ethers, a subgroup of solvents, was associated with neural tube defects (OR: 1.93, 95%CI: 1.17-3.18) and orofacial clefts (OR: 1.95, 95%CI: 1.38-2.75) in the offspring. Only one study investigated the association between maternal occupational exposure to solvents and hypospadias and found an association (OR: 3.63, 95%CI: 1.94-7.17). Results of the included studies were consistent. In our meta-analysis, we found no associations between occupational exposure to pesticides or metals and congenital anomalies in the offspring. LIMITATIONS, REASONS FOR CAUTION: A limited number of studies was included, which made it impossible to calculate pooled estimates for all congenital anomalies, analyse individual chemicals or calculate exposure-response relations. Bias could have been introduced because not all included studies corrected for potentially confounding factors. WIDER IMPLICATIONS OF THE FINDINGS: Employers and female employees should be aware of the possible teratogenic effects of solvent exposure at the workplace. Therefore, is it important that clinicians and occupational health specialist provide women with preconception advice on occupational solvent exposure, to reduce the congenital anomaly risk. STUDY FUNDING/COMPETING INTEREST(S): NSp was paid by the Graduate School of Medical Sciences (MD/PhD program), UMCG, Groningen, the Netherlands. EUROCAT Northern Netherlands is funded by the Dutch Ministry of Health, Welfare and Sports. There are no competing interests. REGISTRATION NUMBER: CRD42017053943.

International audience; OBJECTIVE: To evaluate the effects of ionizing radiation exposure during the first trimester of pregnancy in usual clinical situations.STUDY DESIGN: We conducted a prospective observational cohort study using data collected between 1987 and 2014. This database was authorized by the French "Commission Nationale de l'Informatique et des Libertés". The exposed group consisted of 319 pregnant women exposed to sub diaphragmatic ionizing radiations for diagnostic purposes, during the first trimester of pregnancy, and the control group consisted of 319 pregnant women without any exposure or exposed to non-teratogenic agents. Data on maternal history and radiations exposure were collected on first contact, and pregnancy outcomes were documented at follow-up. An univariate analysis was performed to compare both groups for the main outcomes.RESULTS: Exposure to sub diaphragmatic ionizing radiation for diagnosis purpose (median fetal dose of 3.1 mGy [0.2-130.0]) during the first trimester of pregnancy was not significantly associated with an increased risk of malformations (1.5% vs 1.8%, p = 1.00), miscarriage (7.8% vs 7.2%, p = 0.88), in utero fetal death (0.3% vs 0%, p = 1.00) or fetal growth restriction (5.4% vs 3.5%, p = 0.62).CONCLUSION: Pregnant women exposed to irradiant diagnostic procedures do not present a higher risk of malformations, miscarriage, in utero fetal death or fetal growth restriction and should be reassured, even if the examination focused on the pelvis.

Background Due to the diversity of studies in animal models reporting that molecular mechanisms are involved in the teratogenic effect of the Zika virus (ZIKV), the objective of the present study is to evaluate the methodological quality of these studies, as well as to demonstrate which genes and which molecular pathways are affected by ZIKV in different animal models. Methods This search will be performed in four databases: PubMed/MEDLINE, EMBASE, Web of Science, and Scopus, as well as in the grey literature. The studies selection process will be reported through the PRISMA Statement diagram model. All studies describing the molecular mechanisms possibly involved in the development of malformations caused by embryonic/fetal ZIKV exposure in animal models with an appropriate control group and methodology will be included (including, for instance, randomized and non-randomized studies). All animals used as experimental models for ZIKV teratogenesis may be included as long as exposure to the virus occurred during the embryonic/fetal period. From the selected studies, data will be extracted using a previously prepared standard form. Bias risk evaluation will be conducted following the SYRCLE’s Risk of Bias tool. All data obtained will be tabulated and organized by outcomes (morphological and molecular). Discussion With the proposed systematic review, we expect to present results about the methodological quality of the published studies with animal models that investigated the molecular mechanisms involved in the teratogenic effect of ZIKV, as well as to show the studies with greater reliability. Systematic review registration PROSPERO CRD42019157316

In this review, we explore evidence that hypoxia in the developing human fetus can lead not only to the more commonly accepted disruptive-type defects, but also patterns of anomalies that suggest that hypoxia can exert a more classic teratogenic effect, using the brain as one example. We review neuropathology in the context of intrauterine hypoxia, particularly as it relates to carbon monoxide poisoning, in utero strokes, and homozygous alpha-thalassemia. In general, the associated brain injuries resemble those seen with other causes of hypoxic-ischemic injury. Fetal strokes during development usually lead to loss of brain tissue in areas that do not follow a typical embryologic pattern, and therefore are considered disruptions. However, there is also evidence that fetal brain ischemia can cause more classically recognized patterns of abnormal embryonic neuronal migration and organization such as polymicrogyria, cortical dysplasia, or dysgenesis, including select types of focal cortical dysplasia. This study summarizes available literature and evidence to raise clinicians' awareness regarding the association between hypoxia and congenital anomalies, including brain malformations.

Thalidomide causes teratogenic effects by inducing protein degradation via cereblon (CRBN)‐containing ubiquitin ligase and modification of its substrate specificity. Human P450 cytochromes convert thalidomide into two monohydroxylated metabolites that are considered to contribute to thalidomide effects, through mechanisms that remain unclear. Here, we report that promyelocytic leukaemia zinc finger (PLZF)/ZBTB16 is a CRBN target protein whose degradation is involved in thalidomide‐ and 5‐hydroxythalidomide‐induced teratogenicity. Using a human transcription factor protein array produced in a wheat cell‐free protein synthesis system, PLZF was identified as a thalidomide‐dependent CRBN substrate. PLZF is degraded by the ubiquitin ligase CRL4CRBN in complex with thalidomide, its derivatives or 5‐hydroxythalidomide in a manner dependent on the conserved first and third zinc finger domains of PLZF. Surprisingly, thalidomide and 5‐hydroxythalidomide confer distinctly different substrate specificities to mouse and chicken CRBN, and both compounds cause teratogenic phenotypes in chicken embryos. Consistently, knockdown of Plzf induces short bone formation in chicken limbs. Most importantly, degradation of PLZF protein, but not of the known thalidomide‐dependent CRBN substrate SALL4, was induced by thalidomide or 5‐hydroxythalidomide treatment in chicken embryos. Furthermore, PLZF overexpression partially rescued the thalidomide‐induced phenotypes. Our findings implicate PLZF as an important thalidomide‐induced CRBN neosubstrate involved in thalidomide teratogenicity., The vertebrate transcription factor PLZF/ZBTB16 emerges as potential key mediator of limb defects caused by CRBN ubiquitin ligase modulators, providing insight into the teratogenic contributions of thalidomide metabolites.

In 2015, an outbreak of Zika virus (ZIKV) infection caused a disproportionate increase in the number of cases of microcephaly in Brazil (de Oliveira et al., 2017). Although two major ZIKV lineages referred to as African lineage (ZIKVAF) and Asian lineage (ZIKVAS) have been identified, phylogenetic and genomic analyses pointed to those cases as caused by a ZIKVAS (Faria et al., 2017). This link led scientists to not target ZIKVAF on their investigations. Due to this, information about ZIKVAF circulation in Brazil has been underestimated as well as its epidemic potential. Recently, a study published by Kasprzykowski et al. (2020) identified ZIKVAF present among Brazilian ZIKV sequences. ZIKVAF was identified in non-human primates (NHPs) and mosquitoes in the South and Southeast Brazilian regions, respectively ( Figure 1 ) (de Almeida et al., 2019– Preprint publication; Alencar et al., 2021). At the same time, Aubry et al. (2021) showed ZIKVAF being more transmissible in mosquitoes and more lethal in mice when compared to ZIKVAS. In addition, it was suggested that there was a high epidemic potential of ZIKVAF. Since South and Southeast Brazilian regions are geographically distant (> 1,500 km) and climatically different, and the ZIKVAF was found from different sources, here we raise and bring concerns about the circulation of this lineage in Brazil and the risk it might represent as the cause of a new outbreak of disease in humans potentially associated with birth defects. Open in a separate window Figure 1 Incidence per 100,000 inhabitants of Zika cases in Brazil reported in 2016. Color gradient representing high (darker blue) to low ZIKV incidence (lighter blue). The Brazilian states where ZIKVAF was identified in sylvatic area are also highlighted. Zika virus incidence data were recovered from Brazil Ministry of Health (2018). AC, Acre; AL, Alagoas; AP, Amapa; AM, Amazonas; BA, Bahia; CE, Ceara; DF, Distrito Federal; ES, Espirito Santo; GO, Goias; MA, Maranhao; MT, Mato Grosso; MS, Mato Grosso do Sul; MG, Minas Gerais; PA, Para; PB, Paraiba; PR, Parana; PE, Pernambuco; PI, Piaui; RJ, Rio de Janeiro; RN, Rio Grande do Norte; RS, Rio Grande do Sul; RO, Rondonia; RR, Roraima; SC, Santa Catarina; SP, Sao Paulo; SE, Sergipe; TO, Tocantins.

There are certain critical periods during pregnancy when the fetus is at high risk for exposure to teratogens. Some microorganisms, including Toxoplasma gondii, are known to exhibit teratogenic effects, interfering with fetal development and causing irreversible disturbances. T. gondii is an obligate intracellular parasite and the etiological agent of Toxoplasmosis, a zoonosis that affects one third of the world's population. Although congenital infection can cause severe fetal damage, the injury extension depends on the gestational period of infection, among other factors, like parasite genotype and host immunity. This parasite invades the Central Nervous System (CNS), forming tissue cysts, and can interfere with neurodevelopment, leading to frequent neurological abnormalities associated with T. gondii infection. Therefore, T. gondii is included in the TORCH complex of infectious diseases that may lead to neurological malformations (Toxoplasmosis, Others, Rubella, Cytomegalovirus, and Herpes). The retina is part of CNS, as it is derived from the diencephalon. Except for astrocytes and microglia, retinal cells originate from multipotent neural progenitors. After cell cycle exit, cells migrate to specific layers, undergo morphological and neurochemical differentiation, form synapses and establish their circuits. The retina is organized in nuclear layers intercalated by plexus, responsible for translating and preprocessing light stimuli and for sending this information to the brain visual nuclei for image perception. Ocular toxoplasmosis (OT) is a very debilitating condition and may present high severity in areas in which virulent strains are found. However, little is known about the effect of congenital infection on the biology of retinal progenitors/ immature cells and how this infection may affect the development of this tissue. In this context, this study reviews the effects that congenital infections may cause to the developing retina and the cellular and molecular aspects of these diseases, with special focus on congenital OT.

Background: In our previous studies, we had demonstrated the efficiency and specificity of constructed bladder tissue-specific adenovirus Ad-PSCAE-UPII-E1A-AR (APU-EIA-AR) on bladder cancer. The virus biodistribution and body toxicity in nude mice have also been investigated. However, the safety of the bladder cancer-specific oncolytic adenovirus on fetal mice and F1 mice should be under intense investigation. Objectives: In order to evaluate the teratogenic toxicity of bladder cancer-specific oncolytic adenovirus APU-EIA-AR on mice, in this study, we investigated the fetal mice weight, fetal body length and tail length, fetal skeleton development, as well as the F1 mice weight, growth curve, and major organ pathology. These teratogenic toxicity data of bladder tissue-specific adenovirus Ad-PSCAE- UPII-E1A-AR (AD) would provide safe information prior to embarking on clinical trials. Methods: On the sixth day of being fertilized, the pregnant mice began to be intramuscularly administrated with AD (1×107VP, 1×108VP, 1×109VP) every other day for ten days. The pregnant mice were then divided into two groups. One group was euthanized on the seventeenth day; the fetal mice were taken out, and the bone structure of the infants was observed. The other group was observed until natural childbirth. The Filial Generation (F1) is fed for 30 days; the variations in the growth progress and development were assessed. The mice were then euthanized; The tissues from major organs were harvested and observed under the microscope. Results: In the process of teratogenic toxicity test, the Placenta weight, fetal mice weight, body length, and a tail length of mice fetal in adenovirus treated group did not reveal any alteration. Meanwhile, comparing with the PBS group, there is no obvious change in the skeleton of fetal mice treated with adenovirus. During the development process of F1 mice treated with adenovirus, the changes in mice weight show statistical significance. However, in the progress of the growth curve, this difference is not very obvious. Furthermore, the pathological section showed no obvious alteration in major organs. Conclusion: Our study demonstrated that bladder cancer-specific adenovirus Ad-PSCAE-UPII- E1A-AR appears safe in pregnant mice without any discernable effects on fetal mice and F1 development. Hence, it is relatively safe for tumor gene therapy.

It is hypothesised that the inhibition of the non-canonical Wnt/PCP intracellular signalling cascade by potato glycoalkaloids, [Formula: see text]-solanine and [Formula: see text]-chaconine, results in an increased risk of neural tube defects (NTDs). One very prominent intracellular signalling pathway with substantial implications in the development and closure of the neural tube is the Wnt/PCP pathway. Experimental inhibition of this results in NTDs. A vital element of this signalling cascade is JNK, which controls the transcription of DNA, which controls cell polarity and directional cell migration. JNK inhibition also results in NTDs experimentally. Through their use in cancer research, [Formula: see text]-solanine and [Formula: see text]-chaconine were found to inhibit metastasis by inhibiting JNK, among other intracellular signalling molecules. Thus, this shows that potato glycoalkaloids increase the likelihood of causing NTDs by inhibiting the proper functioning of JNK in the Wnt/PCP pathway, resulting in defective neural tube closure.

Two new biological drugs (vedolizumab and ustekinumab) and one small molecule (tofacitinib) have been recently approved for the treatment of inflammatory bowel disease. Therefore, we must be familiar with the safety of these "new" drugs during pregnancy and breastfeeding. In the present article, we critically review available data on the safety of new biologics (vedolizumab and ustekinumab) and small molecules (tofacitinib) during pregnancy and breastfeeding, with special focus on women with inflammatory bowel disease. Bibliographical searches (MEDLINE) up to April 2020 were performed. The timing and mechanisms of placental transfer of vedolizumab and ustekinumab are expected to be similar to anti-TNF agents. Animal studies show no evidence of adverse effects on pre- or post-natal development after administration of vedolizumab and ustekinumab. Just a few studies including patients treated with vedolizumab or ustekinumab during pregnancy have been published, reporting uneventful pregnancies in most cases. The clinical programme of both drugs and post-marketing studies showed no new safety concerns. Due to the expected safety of vedolizumab and ustekinumab during pregnancy, it may be recommended to plan the final pregnancy dose approximately 8 or 12 weeks, respectively, before the estimated date of delivery. Live vaccines should be avoided for up to a year in children exposed in utero to vedolizumab or ustekinumab unless drug elimination has been documented. Miniscule amounts of vedolizumab and ustekinumab are transferred to breast milk, so breastfeeding is probably safe. There is no evidence of adverse effect of vedolizumab or ustekinumab paternal exposure. Regarding tofacitinib, it is reasonable to assume that this molecule crosses the placenta from the beginning of pregnancy. In animal studies, tofacitinib was feticidal and teratogenic in rats and rabbits, although at exposures many times greater than the standard human dose. Reported outcomes of pregnancy cases identified from tofacitinib randomised controlled trials, post-approval and non-interventional studies, and spontaneous adverse-event reporting appear similar to those observed in the general population. Nevertheless, at present, the use of tofacitinib during pregnancy should be avoided. Although no human studies have reported outcomes of breastfeeding with small molecules such as tofacitinib, this drug is present in lactating rat milk so, at present, breastfeeding should be avoided. Pregnancy among patients with paternal exposure to tofacitinib appears to be safe. In summary, we can conclude that new biologic agents (vedolizumab and ustekinumab) and small molecules (tofacitinib) should be used during pregnancy only if the benefits to the mother outweigh the risks to the mother and unborn child.

Induced pluripotent stem cells (iPSCs) are regarded as a promising option for cell-based regenerative medicine. To obtain safe and efficient iPSC-based cell products, it is necessary to selectively eliminate the residual iPSCs prior to in vivo implantation due to the risk of teratoma formation. Bee venom (BV) has long been used in traditional Chinese medicine to treat inflammatory diseases and relieve pain, and has been shown to exhibit anti-cancer, anti-mutagenic, anti-nociceptive, and radioprotective activities. However, the potential benefits of BV in iPSC therapy, particularly its anti-teratoma activity, have not been examined. In this study, we found that BV selectively induced cell death in iPSCs, but not in iPSC-derived differentiated cells (iPSCs-Diff). BV rapidly disrupted cell membrane integrity and focal adhesions, followed by induction of apoptosis and necroptosis in iPSCs. We also found that BV remarkably enhanced intracellular calcium levels, calpain activation, and reactive oxygen speciesgeneration in iPSCs. BV treatment before in ovo grafting efficiently prevented iPSC-derived teratoma formation. In contrast, no DNA damage was observed in iPSCs-Diff following BV treatment, further demonstrating the safety of BV for use with iPSCs-Diff. Taken together, these findings show that BV has potent anti-teratoma activity by eliminating residual iPSCs, and can be used for the development of effective and safe iPSC-based cell therapies.

Background: The decision of whether to prescribe antidepressants (AD) and anxiolytics (AX) to pregnant women is complex, with serious potential ramifications. Clinicians’ perception of the risk of teratogenicity significantly influences their prescribing decisions and in turn impacts maternal decision making. Our cross-sectional study sought to discern differences in perceived risk between Obstetricians and Gynaecologists (O&Gs) and General Practitioners (GPs) when prescribing these medications in pregnancy. Furthermore, we investigated factors impacting perception, clinicians’ willingness to prescribe and their approach to provision of patient information. Methods: This cross-sectional study was conducted via a nation-wide online SurveyMonkey extended to Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) database-derived affiliates: GP diplomates, fellows and trainees (5409 survey invitations: 545 respondents). O&Gs and GPs were compared using Pearson Chi-squared test for categorical variables and the Student t-test for continuous variables. Results: GPs reported higher rates of being aware of up-to-date medication prescription recommendations (57.6%) compared with O&Gs (44.2%). GPs also reported higher rates of training adequacy in psychotropic prescription (56.1% versus 29.0%). There was evidence to suggest GPs level of confidence in knowledge base, initiation and prescription of AD and AX was higher than those of O&Gs. The mean perception of patient non-compliance was similar between clinician groups (approximately 35%), but GPs perceived the extent of patient anxiety as higher compared to O&Gs (mean 73.7% (SD 21.3) versus 63.1% (SD 24.1), pConclusion: Further development of clinician training in perinatal psychotropic prescription is warranted. Keywords : psychotropics, teratogenicity, pregnant, prescribing, foetal, perception

Thalidomide was first marketed in 1957 but soon withdrawn because of its notorious teratogenicity. Studies on the mechanism of action of thalidomide revealed the pleiotropic properties of this class of drugs, including their anti-inflammatory, antiangiogenic and immunomodulatory activities. Based on their notable activities, thalidomide and its analogues, lenalidomide and pomalidomide, have been repurposed to treat erythema nodosum leprosum, multiple myeloma and other haematological malignancies. Thalidomide analogues were recently found to hijack CRL4CRBN ubiquitin ligase to target a number of cellular proteins for ubiquitination and proteasomal degradation. Thalidomide-mediated degradation of SALL4 and p63, transcription factors essential for embryonic development, very likely plays a critical role in thalidomide embryopathy. In this review, we provide a brief retrospective summary of thalidomide-induced teratogenesis, the mechanism of thalidomide activity, and the latest advances in the molecular mechanism of thalidomide-induced birth malformations.

The rubella virus (RV) was the first virus shown to be teratogenic in humans. The wealth of data on the clinical symptoms associated with congenital rubella syndrome is in stark contrast to an incomplete understanding of the forces leading to the teratogenic alterations in humans. This applies not only to RV, but also to congenital viral infections in general and includes (1) the mode of vertical transmission, even at early gestation, (2) the possible involvement of inflammation as a consequence of an activated innate immune response, and (3) the underlying molecular and cellular alterations. With the progress made in the development of pluripotent stem cell-based models including organoids and embryoids, it is now possible to assess congenital virus infections on a mechanistic level. Moreover, antiviral treatment options can be validated, and newly emerging viruses with a potential impact on human embryonal development, such as that recently reflected by the Zika virus (ZIKV), can be characterized. Here, we discuss human cytomegalovirus (HCMV) and ZIKV in comparison to RV as viruses with well-known congenital pathologies and highlight their analysis on current models for the early phase of human development. This includes the implications of their genetic variability and, as such, virus strain-specific properties for their use as archetype models for congenital virus infections. In this review, we will discuss the use of induced pluripotent stem cells (iPSC) and derived organoid systems for the study of congenital virus infections with a focus on their prominent aetiologies, HCMV, ZIKV, and RV. Their assessment on these models will provide valuable information on how human development is impaired by virus infections; it will also add new insights into the normal progression of human development through the analysis of developmental pathways in the context of virus-induced alterations. These are exciting perspectives for both developmental biology and congenital virology.

The term fetal alcohol spectrum disorder (FASD) refers to the entire suite of deleterious outcomes resulting from embryonic exposure to alcohol. Along with other reviews in this special issue, we provide insight into how animal models, specifically the zebrafish, have informed our understanding of FASD. We first provide a brief introduction to FASD. We discuss the zebrafish as a model organism and its strengths for alcohol research. We detail how zebrafish has been used to model some of the major defects present in FASD. These include behavioral defects, such as social behavior as well as learning and memory, and structural defects, disrupting organs such as the brain, sensory organs, heart, and craniofacial skeleton. We provide insights into how zebrafish research has aided in our understanding of the mechanisms of ethanol teratogenesis. We end by providing some relatively recent advances that zebrafish has provided in characterizing gene-ethanol interactions that may underlie FASD.

Anagyrine, a teratogenic quinolizidine alkaloid found in Lupinus spp., is proposed to undergo metabolism by pregnant cattle to a piperidine alkaloid which inhibits fetal movement, the putative mechanism behind crooked calf syndrome. The objective of this study was to test the hypothesis that anagyrine but not lupanine or sparteine can directly, without metabolism, desensitize nicotinic acetylcholine receptors (nAChR) in a cell culture model. SH-SY5Y cells expressing autonomic nAChR, and TE-671 cells expressing fetal muscle-type nAChR were exposed to lupine alkaloids or Dimethylphenylpiperazinium (DMPP) in log10 molar increments from 10nM to 100μM and then to a fixed concentration of acetylcholine (ACh) (10μM for SH-SY5Y cells and 1μM for TE-671 cells) and the responses measured with a membrane potential sensing dye to assess nAChR activation and desensitization. The selective ganglionic nAChR agonist DMPP used as a positive control, was a potent activator and desensitizer of nAChR expressed by SH-SY5Y cells. Lupanine was a weak agonist and desensitizer in SH-SY5Y cells and sparteine was without effect. Anagyrine acted as a partial agonist in both cell lines with EC50 values of 4.2 and 231μM in SH-SY5Y and TE-671 cells, respectively. Anagyrine was a desensitizer of nAChR with DC50 values of 6.9 and 139μM in SH-SY5Y and TE-671 cells, respectively. These results confirm the hypothesis that anagyrine is a potent and effective desensitizer of nAChR, and that anagyrine can directly, without metabolism, desensitize nAChR. Moreover, serum anagyrine concentrations may be a potential biomarker for lupine teratogenicity in cattle.

Objective To access the effect of vagus nerve stimulation (VNS) on the outcome of pregnancy. Methods We used the International Registry of Antiepileptic Drugs and Pregnancy (EURAP) and its network to search for women receiving adjunctive VNS during pregnancy. Data on maternal and fetal outcomes were extracted from the registry databases and outcomes were evaluated. Results Twenty-six pregnancies were identified in 25 women. All women were exposed to a relative high VNS stimulation level (mean duty cycle 18%, range 5%–51%). Most women had seizures during pregnancy and almost 70% were on antiepileptic drug (AED) polytherapy. The proportion of women with obstetrical interventions was 53.9% (95% confidence interval [CI] 33.4%–73.4%) which was higher compared to the EURAP average (48.2%; 95% CI 47.2%–49.1%). One infant (3.9%; 95% CI 0.1%–19.6%) was born with a major malformation (unilateral congenital glaucoma), which is within the range expected among offspring of AED-treated women. Conclusion Although the present series of VNS-exposed pregnancies is the largest reported to date, the sample size is insufficient to draw any firm conclusions on the safety of VNS in pregnancy but the findings suggest an increased rate of obstetrical interventions, and no clear signal of VNS-related teratogenicity.

Introduction The analgesic metamizole (dipyrone) is not recommended during pregnancy due to limited experience. In several countries, metamizole has no market authorization because of agranulocytosis as a rare but severe adverse effect. However, in others, metamizole is available and widely used as a pain reliever, and its use occurs also during pregnancy, often followed by fears of potential teratogenic risk. Methods This prospective observational cohort study compared pregnancy outcomes of 446 women exposed with metamizole in the first trimester with a randomly selected control cohort comprising 887 women not exposed to metamizole. Relevant data were obtained via structured questionnaires applied during the first trimester and 2 months after the expected date of birth between January 2000 and December 2015. Results The rate of major birth defects (7/373, 1.9%) was not increased in the metamizole cohort (OR adjusted 1.15, 95% CI 0.4-3.5). The cumulative incidences for spontaneous abortions did not reveal a significant difference between the exposed (12.2%, 32/446) and comparison cohort (19.4%, 77/887) (HR adjusted 0.72, 95% CI 0.5-1.1). Elective terminations of pregnancy (ETOP), mostly for “social” reasons, were more frequent in the metamizole (12.5%, 45/446) than in the comparison cohort (9.4%, 50/887; HR adjusted 1.48, 95% CI 0.98-2.2). Conclusions Metamizole exposure in the first trimester does not seem to bear a substantial teratogenic risk. Our study results support reassurance in those instances where metamizole has been used during an unrecognized pregnancy or where its use appears indispensable.

Early-life programming is defined by the adaptive changes made by the fetus in response to an adverse in utero environment. Infantile hemangioma (IH), a vascular anomaly, is the most common tumor of infancy. Here we take IH as the tumor model to propose the stem cell teratogenic hypothesis of tumorigenesis and the potential involvement of the immune system.Teratogenic agents include chemicals, heavy metals, pathogens, and ionizing radiation. To investigate the etiology and pathogenesis of IH, we hypothesized that they result from a teratogenic mechanism. Immature, incompletely differentiated, dysregulated progenitor cells (multipotential stem cells) are arrested in development with vasculogenic, angiogenic, and tumorigenic potential due to exposure to teratogenic agents such as extrinsic factors that disrupt intrinsic factors via molecular mimicry. During the critical period of immunological tolerance, environmental exposure to immunotoxic agents may harness the teratogenic potential in the developing embryo or fetus and modify the early-life programming algorithm by altering normal fetal development, causing malformations, and inducing tumorigenesis. Specifically, exposure to environmental agents may interfere with physiological signaling pathways and contribute to the generation of IH, by several mechanisms.An adverse in utero environment no longer serves as a sustainable environment for proper embryogenesis and normal development. Targeted disruption of stem cells by extrinsic factors can alter the genetic program.This article offers new perspectives to stimulate discussion, explore novel experimental approaches (such as immunotoxicity/vasculotoxicity assays and novel isogenic models), and to address the questions raised to convert the hypotheses into nontoxic, noninvasive treatments.

Thalidomide embryopathy (TE) has affected more than 10,000 babies worldwide. The hypothesis of antiangiogenesis as the teratogenic mechanism of thalidomide has been investigated in several experimental models; but, in humans, it has only been accessed by in vitro studies. Here, we hypothesized the effect of thalidomide upon angiogenesis-related molecules or proteins, previously identified in human embryonic cells, through the in silico STRING-tool. We also investigated ten polymorphisms in angiogenesis-related genes in 38 Brazilian TE individuals and 136 non-affected Brazilians. NOS2 , PTGS2 , and VEGFA polymorphisms were chosen for genotyping. The STRING-tool suggested nitric oxide and β-catenin as the central angiogenesis-related molecules affected by thalidomide’s antiangiogenic property. We did not identify a significant difference of allelic, genotypic or haplotypic frequencies between the groups. We could not predict a risk allele or a protective one for TE in NOS2, PTGS2, or VEGFA , although other genes should be analyzed in larger samples. The role of nitric oxide and β-catenin must be further evaluated, regarding thalidomide teratogenesis complex etiology.

Although the thalidomide tragedy occurred more than 50 years ago, the medication is still being used worldwide for different reasons, and several aspects regarding its teratogenicity remain unsolved. Despite the strict regulation implemented, new cases of thalidomide embryopathy (TE) are still being registered in Brazil. Furthermore, the molecular processes that lead to malformations when the embryo is exposed to thalidomide have not yet been fully identified. In this article, we perform a critical analysis of thalidomide's history in Brazil, highlighting aspects of the occurrence of TE over the decades. Finally, we present the main perspectives and challenges for ongoing surveillance and prevention of TE in Brazil. The effective control of dispensing thalidomide, especially in areas where leprosy is endemic, is one of the most important and challenging points. Furthermore, the emergence of thalidomide analogues is fast approaching, and their availability would pose additional concerns. The understanding of the molecular mechanisms and targets of thalidomide in both experimental and human models is essential for generating new insights into teratogenic mechanisms, so that safer thalidomide analogues can be developed.

Mycophenolate mofetil (MMF) is probably the most common employed immunosuppressant drug in recipients of solid organ transplant and in many autoimmune diseases. In vitro studies, a significant number of single clinical observations and a recent study from a group of different European teratogen information services, have provided very consistent data supporting the existence of a specific MMF embryopathy. The typical malformative pattern of MMF embryopathy includes external ear anomalies ranging from hypoplastic pinna (microtia) to complete absence of pinna (anotia); cleft lip, with or without cleft palate, and ocular anomalies as iris or chorioretinal coloboma and anophthalmia/microphthalmia. Other less frequent features are congenital heart defects, distal limbs anomalies, esophageal atresia, vertebral malformations, diaphragmatic hernia, and kidney and central nervous system anomalies. Neurodevelopmental outcome seems favorable in the small number of patients where information about this issue is available, but neurological deficits have been documented. Physicians in charge of women under MMF therapy should be aware of the potential risk of this drug to cause a specific embryopathy and the need of interrupting the treatment at least six weeks before becoming pregnant. (C) 2016 Elsevier Masson SAS. All rights reserved.