Poisonings in ruminants by Cenostigma pyramidale (Tul.) Gagnon & G.P.Lewis (Fabaceae): A mini-review of teratogenic potential and phytochemical evidence.

Teratogenic plants can be found in pastures in different parts of the world and represent a threat to the reproduction of ruminants. In the northeast region of Brazil, several studies have indicated that Cenostigma pyramidale (Tul.) Gagnon & G.P.Lewis is one of the main poisonous plants that causes reproductive problems in sheep and goats. In this context, the present study reviewed spontaneous and experimental poisonings reports by C. pyramidale in sheep and goats, as well as analyzing the phytochemical evidence related to this species. The scientific documents were retrieved from different databases and, after applying the selection criteria, a total of 16 articles published between 2000 and 2024 were included in this review. Cenostigma pyramidale causes embryonic loss, abortion, and congenital malformations in pregnant sheep and goats in the Brazilian semi-arid region. The main malformations observed in newborn animals are arthrogryposis, scoliosis, micrognathia, multiple skull deformities, cleft palate, and brachygnathism. Many secondary metabolites have already been isolated from C. pyramidale, however, to date, no evidence has been found regarding the possible teratogenic compounds that occur in this plant. From this perspective, new phytochemical studies are necessary to help unravel the mechanisms of action of embryotoxic agents from C. pyramidale.

Teratogenesis, Perinatal, and Neurodevelopmental Outcomes After In Utero Exposure to Antiseizure Medication: Practice Guideline From the AAN, AES, and SMFM.

This practice guideline provides updated evidence-based conclusions and recommendations regarding the effects of antiseizure medications (ASMs) and folic acid supplementation on the prevalence of major congenital malformations (MCMs), adverse perinatal outcomes, and neurodevelopmental outcomes in children born to people with epilepsy of childbearing potential (PWECP). A multidisciplinary panel conducted a systematic review and developed practice recommendations following the process outlined in the 2017 edition of the American Academy of Neurology Clinical Practice Guideline Process Manual. The systematic review includes studies through August 2022. Recommendations are supported by structured rationales that integrate evidence from the systematic review, related evidence, principles of care, and inferences from evidence. The following are some of the major recommendations. When treating PWECP, clinicians should recommend ASMs and doses that optimize both seizure control and fetal outcomes should pregnancy occur, at the earliest possible opportunity preconceptionally. Clinicians must minimize the occurrence of convulsive seizures in PWECP during pregnancy to minimize potential risks to the birth parent and to the fetus. Once a PWECP is already pregnant, clinicians should exercise caution in attempting to remove or replace an ASM that is effective in controlling generalized tonic-clonic or focal-to-bilateral tonic-clonic seizures. Clinicians must consider using lamotrigine, levetiracetam, or oxcarbazepine in PWECP when appropriate based on the patient's epilepsy syndrome, likelihood of achieving seizure control, and comorbidities, to minimize the risk of MCMs. Clinicians must avoid the use of valproic acid in PWECP to minimize the risk of MCMs or neural tube defects (NTDs), if clinically feasible. Clinicians should avoid the use of valproic acid or topiramate in PWECP to minimize the risk of offspring being born small for gestational age, if clinically feasible. To reduce the risk of poor neurodevelopmental outcomes, including autism spectrum disorder and lower IQ, in children born to PWECP, clinicians must avoid the use of valproic acid in PWECP, if clinically feasible. Clinicians should prescribe at least 0.4 mg of folic acid supplementation daily preconceptionally and during pregnancy to any PWECP treated with an ASM to decrease the risk of NTDs and possibly improve neurodevelopmental outcomes in the offspring.

Comprehensive safety evaluation of a novel multitargeting compound XYY-CP1106: A candidate for Alzheimer's disease.

Multitargeting has become a promising strategy for the development of anti-Alzheimer's disease (AD) drugs, considering the complexity of molecular mechanisms in AD pathology. In most pre-clinical studies, the effectiveness of these multi-targeted anti-AD drugs has been demonstrated but comprehensive safety assessments are lacking. Here, the safety evaluation of a novel multi-targeted candidate in AD (XYY-CP1106), characterized by its dual-property of iron chelation and monoamine oxidase B inhibition, was conducted by multifaceted analysis. Acute toxicity in mice was conducted to investigate the safety of oral administration and the maximum tolerated dose of the agent. In vitro Ames analysis, CHL chromosomal aberration analysis, and bone marrow micronucleus analysis were executed to evaluate the genotoxicity. A teratogenesis investigation in pregnant mice were meticulously performed to evaluate the teratogenesis of XYY-CP1106. Furthermore, a 90-day long-term toxicity analysis in rats was investigated to evaluate the cumulative toxicity after long-term administration. Strikingly, no toxic phenomena were found in all investigations, demonstrating relatively high safety profile of the candidate compound. The securing of safety heightened the translational significance of XYY-CP1106 as a novel multi-targeted anti-AD candidate, supporting the rationality of multitargeting strategy in the designs of smart anti-AD drugs.

Differential toxicity and teratogenic effects of the hot water and cold water extracts of Lignosusrhinocerus (Cooke) Ryvarden sclerotium on zebrafish (Danio rerio) embryos.

ETHNOPHARMACOLOGICAL RELEVANCE: The sclerotium of Lignosusrhinocerus (Cooke) Ryvarden is highly valued for its purported medicinal properties. The decoction and macerated materials prepared from the sclerotium are used for treating cancer and other ailments based on extensive traditional knowledge. Scientific evidence from in vitro cytototoxicity, anti-inflammatory and immunomodulatory analyses showed the effectiveness of sclerotial water extracts but toxicity assessment of such preparations has not been reported. AIM OF THE STUDY: This study aimed to compare the differential toxicity and teratogenicity (if any) of the hot water (HW) and cold water (CW) extracts of both wild and cultivated sclerotium on zebrafish (Danio rerio) embryos. MATERIALS AND METHODS: Zebrafish embryos were treated with varying concentrations of the sclerotial HW and CW extracts (0.3-500 µg/mL) for 72 h until hatching. The hatching, mortality and heartbeat rate of the embryos as well as the potential teratogenic effect of the extracts were assessed in embryos post-treatment with the extracts. RESULTS: While the sclerotial HW extracts were nontoxic (LC50 > 500 µg/mL), the sclerotial CW extracts delayed the hatching of the embryos up to 48 h and showed slight toxicity with LC50 values of 398.4 µg/mL and 428.3 µg/mL for the cultivated and wild sclerotium, respectively. The sclerotial CW extracts also induced minor tachycardia in zebrafish larvae. Phenotypic assessment revealed that, while yolk sac edema was observed at high concentrations (300 and 500 µg/mL) of all extracts, curved trunk and bent tail were only observed in the embryos treated with CW extracts of wild sclerotium (300 and 500 µg/mL) but not for CW extracts of cultivated sclerotium at similar concentrations. CONCLUSION: The sclerotial water extracts of L.rhinocerus prepared using different methods have varying degree of toxicity and teratogenicity in zebrafish embryos with the sclerotial CW extracts showed higher toxicity than the HW extracts.

Assessment of Larval Toxicity and the Teratogenic Effect of Three Medicinal Plants Used in the Traditional Treatment of Urinary Tract Infections in Benin.

OBJECTIVE: Mangifera indica Linn, Bridelia ferruginea Benth, and Alstonia boonei De Wild are three plants commonly used in the traditional treatment of urinary tract infections in Benin. This study sets out to assess the cytotoxic and teratogenic effects of extracts of these plants on Artemia salina larvae and hen embryos. METHODS AND RESULTS: The aqueous and ethanolic extracts were obtained by maceration of the powders in solvents. Larval cytotoxicity was performed on Artemia salina larvae. The teratogenic effect of these plants was evaluated on chick embryos at 100 mg/kg and 300 mg/kg. The extracts were injected on the 7th and 14th days of incubation. The quality of the hatched chicks was evaluated by the Tona score followed by the hematological and the biochemical parameter assays. The extracts did not show cytotoxicity on the larvae. The eggs treated with plant extracts at 300 mg/kg significantly lowered the hatchability rate, except for the Mangifera indica Linn. The chicks obtained were all at the very good quality. Then, no significant variation was observed between hematological parameters except white blood cells. For the biochemical parameters, only ASAT showed some significant variations for a few extracts. It would be important to assess the genotoxicity of the plant extracts to determine more broader toxicity. These data justify the use of these medicinal plants in traditional Beninese medicine and constitute in fact a source of production of anti-infectious drugs.

Concordance of 3 alternative teratogenicity assays with results from corresponding in vivo embryo-fetal development studies: Final report from the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) DruSafe working group 2.

An IQ DruSafe working group evaluated the concordance of 3 alternative teratogenicity assays (rat whole embryo culture, rWEC; zebrafish embryo culture, ZEC; and murine embryonic stem cells, mESC) with findings from rat or rabbit embryo-fetal development (EFD) studies. Data for 90 individual compounds from 9 companies were entered into a database. In vivo findings were deemed positive if malformations or embryo-fetal lethality were reported in either species. Each company used their own criteria for deciding whether the alternative assay predicted the in vivo findings. Standard concordance parameters were calculated, positive and negative predictive values (PPV and NPV) were adjusted for the aggregate portfolio prevalence of positive compounds (established by a survey of participating companies), and positive and negative likelihood ratios (LR+ and iLR-) were calculated. Of the 3 assays, only rWEC data were robustly predictive, particularly for negative predictions (NPVadj = 92%). However, both LR+ (4.92) and iLR- (4.72) were statistically significant for the rWEC assay. When analyzed separately for rats, the NPVadj and iLR-values for the rWEC assay increased to 96% and 9.75, respectively. These data suggest that a negative rWEC outcome could defer or replace a rat EFD study in certain regulatory settings.

Pregabalin does not Cause Midline Closure Defect but is not as Innocent as It is Thought.

AIM: To investigate the effects of pregabalin on neural tube closure, and other potential effects on other organ systems in a chick embryo model. MATERIAL AND METHODS: Fertilized chicken eggs were divided into groups, and different doses of pregabalin was administered. All embryos were harvested in the 8th day of incubation, and investigated both macroscopically and microscopically against any developmental malformations caused by Pregabalin. RESULTS: Macroscopically not any malformations were detected but macrosomia was statistically significant in medium and high dose groups. Microscopically, vertebral lamina ossification was delayed in some embryos in high dose group but not interpreted as midline closure defect and also not statistically significant. Decrease in the number of renal glomerulus and increase in the tubular damage was statistically significant in medium and high dose groups. Cardiomegaly was also found in some embryos in middle and high dose groups but not statistically significant. CONCLUSION: The use of pregabalin does not cause neural tube closure defect in the embryo unless not exceed recommended maximum dose. Causing macrosomia instead of developmental retardation by Pregabalin is in conflict with the literature. This study revealed that Pregabalin causes fetal nephrotoxicity and macrosomia. These findings indicate that the use of Pregabalin in pregnancy still needs to be accounted as suspicious.

Investigation of NH3 as a selective thyroid hormone receptor modulator in larval zebrafish (Danio rerio).

Thyroid hormones (THs) are essential for normal vertebrate development and diverse environmental chemicals are hypothesized to cause developmental toxicity by disrupting TH-mediated signaling. The larval zebrafish (Danio rerio) is an emerging in vivo model of developmental TH disruption; however, the effects of TR antagonism have not yet been studied in zebrafish. NH3, generally considered a potent and specific thyroid hormone receptor (TR) antagonist, has been used in rodents and Xenopus laevis to characterize phenotypes of TR antagonism. The objective of this study is to determine the effects of NH3 on endpoints previously determined to be TH-sensitive in larval zebrafish, specifically teratology and mortality, photomotor behavior, and mRNA expression of TH signaling genes. Zebrafish embryos were exposed to NH3 via static waterborne exposure at concentrations ranging from 0.001 to 10 µM beginning at 6 h post-fertilization (hpf) through 5 days post fertilization (dpf). Significant mortality and teratogenesis was observed at 3, 4, and 5 dpf in zebrafish exposed to NH3 at 10 µM. At concentrations that did not cause significant mortality, NH3 did not exert a consistent antagonistic effect on photomotor behavior assays or mRNA expression when administered alone or in the presence of exogenous T4. Rather, depending on the NH3 concentration and larval age NH3 decreased or increased swimming triggered by transition from light to dark. Similarly, inconsistent antagonistic and agonistic effects on mRNA expression of TH signaling genes were noted following treatment with NH3 alone. NH3 did inhibit T4 (30 nM)-induced gene expression; however, this was only consistently observed at a concentration of NH3 (10 µM) that also caused significant mortality. Collectively, these results suggest that NH3 does not act solely as a TR antagonist in larval zebrafish, but instead exhibits complex modulatory effects on TR activity. These data support the hypothesis that NH3 is a selective thyroid hormone receptor modulator. Further studies of NH3 interactions with the zebrafish thyroid hormone receptor are required to characterize the activity of NH3 in target tissues of the larval zebrafish at the molecular level, highlighting the importance of characterizing NH3 effects in specific models of TH-disruption to better interpret its actions in mechanistic screens of environmental chemicals for TH action.

Short- and long-term exposures of the synthetic cannabinoid 5F-APINAC induce metabolomic alterations associated with neurotransmitter systems and embryotoxicity confirmed by teratogenicity in zebrafish.

INTRODUCTION: Synthetic cannabinoids are abused substances with strong psychoactive effects. Little is known about the effects on neurotransmission and the toxicity of the second-generation cannabinoid 5F-APINAC. The objective was to assess the influence of short- and long-term exposures of 5F-APINAC on metabolites associated with neurotransmission on zebrafish. METHODS: Short-term ("acute", 4 h) and long-term ("chronic", 96 h) exposures to 5F-APINAC were performed at 0.001, 0.01, 0.1, 1.0 and 10 µM. Intervention groups were compared with a vehicle control. Each group n = 20 zebrafish eggs/larvae. Metabolites related to neurotransmission were determined. RESULTS: In chronic exposure, larvae exposed to 10 µM 5F-APINAC presented morphological and developmental alterations. GABA had the lowest concentrations at higher exposure in acute (p < 0.01) and chronic (p < 0.001) experiments. Glutamine showed a descending trend in the acute experiment, but an ascending trend in the chronic exposure (p < 0.05). In chronic exposure, tryptophan presented an overall descending trend, but with a neat increase at 10 µM 5F-APINAC (p < 0.001). Tryptamine in acute exposure presented lower (p < 0.05) concentrations at higher doses. Dopamine and acetylcholine presented highest (p < 0.05) concentrations in the acute and chronic exposures, but with a drop at the highest doses in the chronic experiments. In chronic exposure, xanthurenic acid decreased, except for the highest dose. Picolinic acid was increased at the highest doses in the chronic experiment (p < 0.001). CONCLUSIONS: Short- and long-term exposures induced metabolomic alterations associated with the gamma-aminobutyric acid/glutamic acid, dopaminergic/adrenergic, cholinergic neurotransmitter systems, and the kynurenine pathway. Chronic exposure at 10 µM 5F-APINAC was associated with embryotoxicity confirmed by teratogenesis.

The overview of current evidence on the reproductive toxicity of dibutyl phthalate.

Over the past years, many legitimate concerns have been raised about the effects of dibutyl phthalate (DBP) as an endocrine disruptor, especially on reproduction. The aim of this publication is to critically review the literature related to the developmental and reproductive toxicity of DBP in animals. Several electronic databases were systematically searched until 2019. Studies were qualified for the review if they: linked exposure to DPB with reproduction, were published in English after 1990, and were conducted on animals. In the studies of the testicular effects of DBP on experimental animals, the most common effects of exposure included reduced fertility, atrophic changes in male gonads, degenerative changes in the epididymis, as well as a reduction in sperm count and motility, cryptorchidism, hypospadias, poor sperm quality and other genital defects (decreased testicular weight, delayed spermatogenesis, Leydig cell aggregation, impaired Sertoli cell maturation, and significant inhibitions of testicular enzymes). The embryotoxic effects of DBP on laboratory animals included mainly an increase in fetal resorption and a decrease in live births. The teratogenic effects of DBP also manifest as skeletal malformations in fetuses, malformations of male gonads and other genital effects. On the basis of the literature data, it is clearly demonstrated that DBP shows anti-androgenic effects; however, there are also reports confirming its weak estrogenic effect. Additionally, lower doses cause more adverse effects than the highest dose, which is an important fact because of the widespread environmental exposure to DBP. The studies clearly confirm that DBP is an endocrine disruptor. Int J Occup Med Environ Health. 2021;34(1):15-37.

Wnt/PCP signalling cascade disruption by JNK inhibition as a potential mechanism underlying the teratogenic effects of potato glycoalkaloids.

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.

Teratogenesis in the chick embryo following post-gastrulation exposure to Y-27632 -effect of Y-27632 on embryonic development.

The pyridine derivative Y-27632 inhibits Rho-associated coiled-coil-containing protein kinase (ROCK) signaling, which is involved in numerous developmental processes during embryogenesis, primarily by controlling actin-cytoskeleton assembly and cell contractility. Somite formation requires rearrangement of the cytoskeleton and assists in major morphological mechanisms, including ventral body wall formation. Administration of Y-27632 impairs cytoskeletal arrangements in post-gastrulation chick embryos leading to ventral body wall defects (VBWD) at later stages of development. The aim of this study was to investigate the effect of Y-27632 on somite development in post-gastrulation chick embryos during early embryogenesis. After 60 h incubation, embryos in shell-less culture were treated with Y-27632 or vehicle for controls. Following administration, abnormality rates were assessed. In treatment groups, embryos showed a kinked longitudinal body axis. Western blot confirmed impaired ROCK downstream signaling by decreased expression of phosphorylated cofilin-2. Histology, Lysotracker studies and RT-PCR demonstrated increased cell death in somites, the neural tube and the ectoderm. RT-PCR and Western blot of factors known to be involved during somitogenesis revealed reduced expression in the treatment group compared to controls. We hypothesize that administration of Y-27632 disrupts somite development causing axial kinking and embryo malformation, which may lead to VBWD.

Differences in teratogenicity of some vitamin K antagonist substances used as human therapeutic or rodenticide are due to major differences in their fate after an oral administration.

All vitamin K antagonist active substances used as rodenticides were reclassified in 2016 by the European authorities as active substances "toxic for reproduction", using a "read-across" alternative method based on warfarin, a human vitamin K antagonist drug. Recent study suggested that all vitamin K antagonist active substances are not all teratogenic. Using a neonatal exposure protocol, warfarin evokes skeletal deformities in rats, while bromadiolone, a widely used second-generation anticoagulant rodenticide, failed to cause such effects. Herein, using a rat model we investigated the mechanisms that may explain teratogenicity differences between warfarin and bromadiolone, despite their similar vitamin K antagonist mechanism of action. This study also included coumatetralyl, a first-generation active substance rodenticide. Pharmacokinetic studies were conducted in rats to evaluate a potential difference in the transfer of vitamin K antagonists from mother to fetus. The data clearly demonstrate that warfarin is highly transferred from the mother to the fetus during gestation or lactation. In contrast, bromadiolone transfer from dam to the fetus is modest (5% compared to warfarin). This difference appears to be associated to almost complete uptake of bromadiolone by mother's liver, resulting in very low exposure in plasma and eventually in other peripheric tissues. This study suggests that the pharmacokinetic properties of vitamin K antagonists are not identical and could challenge the classification of such active substances as "toxic for reproduction".

Protective Effect of Flax Seed on Brain Teratogenicity Induced by Lamotrigine in Rat Fetuses.

The objective of this study was to assess the effects of the hydroalcoholic extract of flax seed on the teratogenic activity of lamotrigine in the brain of fetuses of rats who had received the drug. In this experimental study, 40 female rats were assigned randomly into four groups and after mating and confirming the vaginal plug, the control animals (group 1) were kept with no intervention, and the other three experimental groups were intraperitoneally injected with respective lamotrigine (75 mg/kg), and 100 and 200 mg/kg of flax seed hydroalcoholic extract. The drug was administered during the organogenesis period. Rats were sacrificed at the 20th day of gestation (one day before term) and fetuses were macroscopically examined, weighed and crown-rump length measured. Fetal brain specimens were processed for H&E and for histological study, using the ImageJ software. Results showed that fetuses of the experimental groups that received lamotrigine had reduced body weight, prefrontal cortical and hippocampal thickness, and pyramidal neurons in the hip-pocampus; Nevertheless, these factors were improved by high-dose administration of flax seed in the experimental group 3 and 4. Our research concludes that lamotrigine negatively influences the development of brain in rats and flax seed has a protective impact on these complications.

24-Epibrassinolide protects against ethanol-induced behavioural teratogenesis in zebrafish embryo.

Embryonic studies have demonstrated the neurotoxic, teratogenic, and neurobehavioral toxicity of ethanol (EtOH). Although multiple mechanisms may contribute to these effects, oxidative stress has been described as the major damage pathway. In this regard, natural antioxidants have the potential to counteract oxidative stress-induced cellular damage. Therefore, the present study aimed to investigate the potential protective role of 24-epibrassinolide (24-EPI), a natural brassinosteroid with proved antioxidant properties, in EtOH-induced teratogenic effects during early zebrafish development. Embryos (~2 h post-fertilization - hpf) were exposed to 1 % EtOH, co-exposed to 24-EPI (0.01, 0.1 and 1 µM) and to 24-EPI alone (1 µM) for 24 h. Following exposure, biochemical evaluations were made at 26 hpf, developmental analysis was made throughout the embryo-larval period, and behavioural responses were evaluated at 120 hpf. Exposure to 1 % EtOH caused an increase in the number of malformations, which were diminished by 24-EPI. In addition, EtOH induced an accumulation of GSSG and consequent reduction of GSH:GSSG ratio, indicating the involvement of oxidative mechanisms in the EtOH-induced effects. These were reverted by 24-EPI as proved by the GSSG levels and GSH:GSSG ratio that returned to control values. Furthermore, exposure to EtOH resulted in behavioural deficits at 120 hpf as observed by the disrupted response to an aversive stimulus, suggesting the involvement of neurotoxic mechanisms. 24-EPI restored the behavioural deficits observed in a dose-dependent manner. The absence of effects in the embryos exposed solely to 24-EPI showed its safety during the exposure period. In conclusion, EtOH caused developmental teratogenicity and behavioural toxicity by inducing glutathione changes, which were prevented by 24-EPI.

Elimination of Teratogenic Human Induced Pluripotent Stem Cells by Bee Venom via Calcium-Calpain Pathway.

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.

A novel screening test to predict the developmental toxicity of drugs using human induced pluripotent stem cells.

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.

Iron nanoparticle bio-interactions evaluated in Xenopus laevis embryos, a model for studying the safety of ingested nanoparticles.

Iron nanoparticles (NPs) have been proposed as a tool in very different fields such as environmental remediation and biomedical applications, including food fortification against iron deficiency, even if there is still concern about their safety. Here, we propose Xenopus laevis embryos as a suitable model to investigate the toxicity and the bio-interactions at the intestinal barrier of Fe3O4 and zerovalent iron (ZVI) NPs compared to Fe(II) and (III) salts in the 5 to 100 mg Fe/L concentration range using the Frog Embryo Teratogenesis Assay in Xenopus (FETAX). Our results demonstrated that, at concentrations at which iron salts induce adverse effects, both iron NPs do not cause acute toxicity or teratogenicity even if they accumulate massively in the embryo gut. Prussian blue staining, confocal and electron microscopy allowed mapping of iron NPs in enterocytes, along the paracellular spaces and at the level of the basement membrane of a well-preserved intestinal epithelium. Furthermore, the high bioaccumulation factor and the increase in embryo length after exposure to iron NPs suggest greater iron intake, an essential element for organisms. Together, these results improve the knowledge on the safety of orally ingested iron NPs and their interaction with the intestinal barrier, useful for defining the potential risks associated with their use in food/feed fortification.

Crack cocaine smoke on pregnant rats: Maternal evaluation and teratogenic effect.

This study aimed to evaluate maternal toxicity, teratogenic, and placental oxidative effects resulting from the exposure of rats to crack cocaine smoke during pregnancy. Pregnant rats were exposed either to the smoke of crack and ashes (Crack) or to the smoke of ashes alone, nonexposed or pair-fed with the Crack group. Crack group was exposed to the smoke resulting from the burning of 250 mg of crack for 10 min, twice a day, from 7 days prior to mating until cesarian on gestational day 20. Placental oxidative stress and classical parameters of maternal and fetal evaluation were studied, in addition to the morphometric analysis of the fetal metamers. Even in the absence of changes in body weight gain and feed intake, crack altered the reproductive performance of dams. Exposure to the drug promoted late closure of the fetal fontanel. Furthermore, the morphometric study of the brain mass (BM)/skull cap ratio revealed a decrease in the BM of the fetuses exposed to the drug. Exposure to crack has an oxidative potential in fetal development, since exposure to the drug promoted placental lipid peroxidation. Our study showed that daily exposure to crack, even in lower frequency than that performed by users, has a teratogenic potential.