Maternal Toxicity Research Articles

English

The use of pesticide mixture to combat increased resistance by pest, to single chemical insecticide has brought about an increase in the use of pesticide mixture from different class, with its attendant toxicity. The objective of this study was to evaluate the maternal and foetal toxicity associated with dimethoate and cypermethrin, the two insecticides that are normally mixed to reduce pest resistance. 100 confirmed-mated (gravid) females were assigned at random among the four groups (control – tap water only):   group 1- very low dose-10 mg/kg/day of Cypermethrin (5.3% LD50) + 1.0 mg/kg/day Dimethoate (0.7% of LD50); group 2- intermediate dose- 19 mg/kg/day of Cypermethrin (10% LD50) + 1.4 mg/kg/day  Dimethoate (0.9% of LD50); and group 3- high dose-  38 mg/kg/day of Cypermethrin (20% LD50) + 12.8 mg/kg/day  Dimethoate (8.5% of LD50). The regimens were administered orally at gestation days (GD) 6-20 to pregnant rats. The dams were examined for mortality, moribundity, pertinent behavioural changes and signs of overt toxicity. Animals were weighed on day 0, and once at every 3-day intervals during the dosing period and on GD 21. The pregnant rats were sacrificed by decapitation on GD 21, the uteri were removed and the fetuses examined for litter weight, size, resorption, sex ratio, absolute and relative organ weight. The results showed that combined pesticide exposure caused overt toxic signs in the dams. However, the maternal body weight and relative organ weight were not adversely affected except in the heart that showed significant alteration. Although, the litter weight was not adversely compromised, the result showed that the prenatal exposure to pesticide mixture caused increased foetal resorption, decreased the litter size and offsprings’ male/female ratio. The study concludes that prenatal co-exposure to cypermethrin and dimethoate has adverse consequences on some maternal and foetal parameters in albino rats. Key words: Pesticide mixture, litter size, sex ratio, litter weight, maternal relative organ weight.

The Threshold of Toxicological Concern for prenatal developmental toxicity in rats and rabbits

The Threshold Toxicological Concern (TTC) is based on the concept that in absence of experimental data reasonable assurance of safety can be given if exposure is sufficiently low.Using the REACH database the low 5th percentile of the NO(A)EL distribution, for prenatal developmental toxicity (OECD guideline 414) was determined. For rats, (434 NO(A)ELs values) for maternal toxicity, this value was 10 mg/kg-bw/day. For developmental toxicity (469 NO(A)ELs): 13 mg/kg-bw/day. For rabbits, (100 NO(A)ELs), the value for maternal toxicity was 4 mg/kg-bw/day, for developmental toxicity, (112 NO(A)EL values): 10 mg/kg-bw/day. The maternal organism may thus be slightly more sensitive than the fetus. Combining REACH- (industrial chemicals) and published BASF-data (mostly agrochemicals), 537 unique compounds with NO(A)EL values for developmental toxicity in rats and 150 in rabbits were evaluated. The low 5th percentile NO(A)EL for developmental toxicity in rats was 10 mg/kg-bw/day and 9.5 mg/kg-bw/day for rabbits. Using an assessment factor of 100, a TTC value for developmental toxicity of 100 μg/kg-bw/day for rats and 95 μg/kg-bw/day for rabbits is calculated. These values could serve as guidance whether or not to perform an animal experiment, if exposure is sufficiently low. In emergency situations this value may be useful for a first tier risk assessment.

Developmental and reproductive toxicological evaluation of arachidonic acid (ARA)-Rich oil and docosahexaenoic acid (DHA)-Rich oil

The purpose of this study was to investigate the reproductive and developmental toxicity of dietary exposure to DHA-rich oil from Schizochytrium sp. and ARA-rich oil from Mortierella alpina. In a developmental toxicity study, pregnant Wistar rats were untreated (control) or administered corn oil (vehicle control), 1000, 2500, or 5000 mg/kg bw/day of DHA-rich oil or ARA-rich oil via gavage from gestation days 6 through 20. In the reproductive toxicity study, male and female Wistar rats were administered vehicle control (corn oil), or 1000, 2500, or 5000 mg/kg bw/day of DHA- or ARA-rich oil via gavage throughout the mating period, pregnancy, and the nursing and lactation period. Differences in the number of fetuses, fetal skeletal malformations, and external and visceral anomalies in the developmental study and mortality, clinical signs, fertility indices, physical observations, gross necropsy findings, and gestation period length in the reproductive toxicity study were not dose-related or significantly different from control groups, and were not considered to be treatment related. The no observed adverse effect level (NOAEL) for maternal toxicity and embryo/fetal development and for paternal or maternal treatment-related reproductive toxicity for the DHA-rich oil and ARA-rich oil administered by gavage, was 5000 mg/kg bw/day.

Maternal side effects & fetal neuroprotection according to body mass index after magnesium sulfate in a multicenter randomized controlled trial

Objective: Evidence supports the need of dose-adjustment of several drugs according to body mass index (BMI) to prevent toxicity in the underweight, and ensure efficacy in obese women. However, for MgSO4 neuroprotection, the effect of BMI on maternal toxicity and fetal neuroprotection is understudied. We analyze the effect of BMI on maternal/infant outcomes after MgSO4.Methods: Secondary analysis of a clinical trial that studied MgSO4 neuroprotection. Maternal side effects, magnesium cord levels, and offspring cerebral palsy/death were analyzed along BMI strata using ANOVA and chi-square test. Logistic regression was used to calculate adjusted odds ratios according to the treatment and BMI, using nonobese that received placebo as reference. Interaction analyses were performed to validate differential efficacy of BMI.Results: From 2241 women, more side effects and higher magnesium cord levels were seen in underweight women (p = 0.05). MgSO4 neuroprotection was effective in the non-obese (p = 0.02), but not in obese women (p = 1.00). In multivariate analyses, MgSO4 significantly reduced cerebral palsy only in nonobese women. Interaction analyses showed the moderator effect of BMI (p = 0.169). Increasing MgSO4 dose in obese mothers may ensure neuroprotective efficacy without representing increased maternal risks. Considering costs of studying this association, current analysis may form the basis for reasonable practice.

Use of TNF-inhibitors and ustekinumab for psoriasis during pregnancy: A patient series

From 2002 to 2016 a total of seven women with severe refractory psoriasis were exposed to the TNF-inhibitors infliximab and adalimumab or to the IL12/23 inhibitor ustekinumab during one or more pregnancies. Maternal, fetal or teratogenic toxicity were not detected during pregnancy and puerperium. All pregnancies were uneventful and resulted in delivery of 10 healthy children in total, one of the women is due February 2017. Postpartum, five of the women were lactating, but none of the women or newborns developed adverse reactions. Data on safety of treatment during breastfeeding are sparse, but so far appears to be safe due to the lack of absorption across the gastrointestinal lining. Currently biological therapy with either TNF-inhibitors or ustekinumab is not recommended during pregnancy, however in selected women with severe psoriasis these treatment modalities may be considered.

Prenatal Developmental Toxicity Study of Glycosides-based Standardized Fenugreek Seed Extract in Rats.

Context:Glycoside-based standardized fenugreek seed extract (SFSE-G) demonstrated promising efficacy in animal models of immune-inflammatory conditions.Aim:The present study was aimed at embryo-fetal development toxicity evaluation of SFSE-G in Wistar rats as per guideline No. 414 of the Organization for Economic Co-operation and Development (OECD).Material and Methods:Mated female rats were randomized into four groups of 30 each and received oral doses of either SFSE-G at 250, 500, and 1000 mg/kg or vehicle (water) during the period of gestation (postconception) from gestational day 5 (GD5, an implantation day) until 1 day before cesarean sections (GD19). Maternal food consumption, body weights, and clinical signs were monitored throughout gestation. Cesarean sections were performed on GD20 and fetal observations (gravid uterine weight, implantation sites, early and late resorptions, live and dead fetuses) were recorded. Live fetuses were weighed and examined for external, visceral, and skeletal variations and malformations.Results:None of the SFSE-G-treated groups showed maternal and embryo–fetal toxicity. Occasional and incidental skeletal and visceral malformations were observed and found to be spontaneous and unrelated to the treatment.Conclusion:Oral exposure of SFSE-G during the prenatal period did not show significant maternal and embryo-fetal toxicity up to a dose of 1000 mg/kg in rats. Therefore, the no-observed-adverse-effect level for SFSE-G for prenatal oral exposure was considered to be 1000 mg/kg.SUMMARY Prenatal toxicity of glycoside-based standardized fenugreek seed extract (SFSE-G) was evaluated.SFSE-G was orally gavaged to rats on gestational days 5-19 with a limit dose of 1000 mg/kg.SFSE-G did not show maternal or developmental toxicity.SFSE-G showed NOAEL of 1000 mg/kg for prenatal exposure in female rats. Abbreviations used: CPCSEA: Committee for the Purpose of Control and Supervision of Experiments on Animals; GD: Gestational day; GRAS: Generally recognized as safe; HED: Human equivalent dose; NOAEL: No-observed adverse effect levels; OECD: Organization for Economic Co-operation and Development; SFSE-G: glycoside-based standardized fenugreek seed extract.

Captan (Pesticides).

Food Safety Commission of Japan (FSCJ) conducted a risk assessment of captan (CAS No. 133-06-2), a phthalimide fungicide, based on results from various studies. Major adverse effects of captan were observed in suppressed body weight, and also in duodenal mucosal hyperplasia in mice. No adverse effect on fertility was detected. Increases in incidence of duodenal adenoma and adenocarcinoma were identified in mice. Negative results were however obtained from a gene mutation assay of the target in transgenic mice. No genotoxicity relevant to human health of captan was recognized in spite of the positive results in vitro. Therefore, a genotoxic mechanism was unlikely involved in the tumor development, and it enabled us to establish a threshold in the assessment. In developmental toxicity studies, captan, at the doses causing maternal toxicity, increased external alterations as well as skeletal and soft tissue alterations in the fetus of rabbits and hamsters. No captan-induced teratogenicity was detected in rats. Captan (parent compound only) was identified as the residue definition for dietary risk assessment in agricultural and livestock products. The lowest no-observed-adverse-effect level (NOAEL) obtained from all the studies was 10 mg/kg bw/day. FSCJ specified an acceptable daily intake (ADI) of 0.1 mg/kg bw/day by applying a safety factor of 100 to the NOAEL. The lowest NOAEL for potential adverse effects of a single oral administration of captan was 30 mg/kg bw/day in a developmental toxicity study in rabbits. FSCJ specified an acute reference dose (ARfD) of 0.3 mg/kg bw, for women who are or may be pregnant, by applying a safety factor of 100 to the NOAEL. In addition, FSCJ specified an ARfD of 3 mg/kg bw, for general population, by applying a safety factor of 100 to the no-observed-effect level (NOEL) of 300 mg/kg bw obtained from a general pharmacology study in mice.

Toxicological evaluation of the flavour ingredient N -(1-((4-amino-2,2-dioxido-1 H -benzo[ c ][1,2,6]thiadiazin-5-yl)oxy)-2-methylpropan-2-yl)-2,6-dimethylisonicotinamide (S2218)

A toxicological evaluation of N-(1-((4-amino-2,2-dioxido-1H-benzo[c][1,2,6]thiadiazin-5-yl)oxy)-2-methylpropan-2-yl)-2,6-dimethylisonicotinamide (S2218; CAS 1622458-34-7), a flavour with modifying properties, was completed for the purpose of assessing its safety for use in food and beverage applications. S2218 exhibited minimal oxidative metabolism in vitro, and in rat pharmacokinetic studies, the compound was poorly orally bioavailable and rapidly eliminated. S2218 was not found to be mutagenic in an in vitro bacterial reverse mutation assay, and was found to be neither clastogenic nor aneugenic in an in vitro mammalian cell micronucleus assay. In subchronic oral toxicity studies in male and female rats, the NOAEL was 140mg/kg bw/day (highest dose tested) for S2218 sulfate salt (S8069) when administered as a food ad-mix for 13 consecutive weeks. Furthermore, S2218 sulfate salt demonstrated a lack of maternal toxicity, as well as adverse effects on fetal morphology at the highest dose tested, providing a NOAEL of 1000mg/kg bw/day for both maternal toxicity and embryo/fetal development when administered orally during gestation to pregnant rats.

Pre- and postnatal evaluation of offspring rats exposed to Origanum vulgare essential oil during mating, gestation and lactation

ABSTRACT: Despite the increasing use of oregano ( Origanum vulgare L.) essential oil for therapeutic purposes, pre- and postnatal development of animals offspring exposed to this oil has not yet been evaluated. In line with previous concerns of genotoxicity, in this study adult rats were exposed to different doses of oregano essential oil (3, 9 and 27% vol/vol) during pre-mating, mating, gestation and lactation. Prenatal screening included fetal development and uterine inspection, where the reproductive rate of females such as breeding, pregnancy, delivery, viability and post-implantation loss rate were measured. Postnatal evaluation of rat offspring included motor development, neuroendocrine and behavioral assessment. Body weight of rat dams and signs of dystocia were evaluated daily. Development of physic characteristics and reflex tests of puppies were also assessed. Additionally, these rats, when adults, were submitted to sexual and open field behavioral tests. The main differences among the groups were observed in the indices of mating, pregnancy and post-implantation loss (P<0.01). Results demonstrated that the treatment of parental generation with oregano essential oil has the potential to affect the developing fetuses at the highest dose used, but without causing maternal toxicity and changes in general behavior and development of the progeny.

Isofetamid (Pesticides).

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of isofetamid (CAS No. 875915-78-9), a phenacyl amide fungicide, based on results from various studies. Major treatment-related effects of isofetamid were observed on liver (hepatocellular hypertrophy) and on thyroid (hypertrophy of follicular epithelial cell). None of neurotoxicity, carcinogenicity, reproductive toxicity, teratogenicity, immunotoxicity and genotoxicity were observed. Based on the results from various studies, only parent isofetamid was identified as the relevant substance to the residue definition for dietary risk assessment in agricultural products. The lowest no-observed-adverse-effect level (NOAEL) obtained in all the toxicity studies was 5.34 mg/kg bw/day in a one-year chronic toxicity study in dogs. FSCJ has established an acceptable daily intake (ADI) of 0.053 mg/kg bw/day, applying a safety factor of 100 to the NOAEL. The lowest NOAEL for adverse effects that would be likely to be elicited by a single oral administration of isofetamid was 300 mg/kg bw/day, which is obtained on the maternal toxicity in rabbits. FSCJ specified an acute reference dose (ARfD) of 3 mg/kg bw/day, applying a safety factor of 100 to the NOAEL.

Folpet (Pesticides).

Food Safety Commission of Japan (FSCJ) conducted a risk assessment of folpet (CAS No. 133-07-3), a phthalimide fungicide, based on results from various studies. Major adverse effects of folpet were observed in hyper-keratosis in rats and in duodenal mucosal hyperplasia in mice. No neurotoxicity and adverse effect on fertility were detected. Increases in the incidence of duodenal adenoma and adenocarcinoma were identified in carcinogenicity studies in mice. FSCJ recognized no genotoxicity relevant to human health of folpet in spite of the positive results in vitro. Therefore, a genotoxic mechanism was unlikely involved in the tumor development, and it enabled us to establish a threshold in the assessment. In developmental toxicity studies, no adverse effects observed in fetus at the dose without maternal toxicity. No folpet-induced teratogenicity was detected in rats. Folpet (parent compound only) was identified as the residue definition for dietary risk assessment in agricultural products. The lowest no-observed-adverse-effect level (NOAEL) obtained in all the studies was 10 mg/kg bw/day in several studies in dogs, rats and rabbits. FSCJ specified an acceptable daily intake (ADI) of 0.1 mg/kg bw/day by applying a safety factor of 100 to the NOAEL. The lowest NOAEL for potential adverse effects of a single oral administration of folpet was 10 mg/kg bw/day in a developmental toxicity study in rabbits. FSCJ specified an acute reference dose (ARfD) of 0.1 mg/kg bw/day, for women who are or may be pregnant, by applying a safety factor of 100 to the NOAEL. FSCJ considered it unnecessary to specify ARfD for general population.

Toxic effect of acrylamide on the development of hippocampal neurons of weaning rats

Although numerous studies have examined the neurotoxicity of acrylamide in adult animals, the effects on neuronal development in the embryonic and lactational periods are largely unknown. Thus, we examined the toxicity of acrylamide on neuronal development in the hippocampus of fetal rats during pregnancy. Sprague-Dawley rats were mated with male rats at a 1:1 ratio. Rats were administered 0, 5, 10 or 20 mg/kg acrylamide intragastrically from embryonic days 6-21. The gait scores were examined in pregnant rats in each group to analyze maternal toxicity. Eight weaning rats from each group were also euthanized on postnatal day 21 for follow-up studies. Nissl staining was used to observe histological change in the hippocampus. Immunohistochemistry was conducted to observe the condition of neurites, including dendrites and axons. Western blot assay was used to measure the expression levels of the specific nerve axon membrane protein, growth associated protein 43, and the presynaptic vesicle membrane specific protein, synaptophysin. The gait scores of gravid rats significantly increased, suggesting that acrylamide induced maternal motor dysfunction. The number of neurons, as well as expression of growth associated protein 43 and synaptophysin, was reduced with increasing acrylamide dose in postnatal day 21 weaning rats. These data suggest that acrylamide exerts dose-dependent toxic effects on the growth and development of hippocampal neurons of weaning rats.

Exposure to benzo[a]pyrene impairs decidualization and decidual angiogenesis in mice during early pregnancy

Benzo[a]pyrene (BaP) is a ubiquitous environmental persistent organic pollutant and a well-known endocrine disruptor. BaP exposure could alter the steroid balance in females. Endometrium decidualization and decidual angiogenesis are critical events for embryo implantation and pregnancy maintenance during early pregnancy and are modulated by steroids. However, the effect of BaP on decidualization is not clear. This study aimed to explore the effects of BaP on decidualization and decidual angiogenesis in pregnant mice. The result showed that the uteri in the BaP-treated groups were smaller and exhibited an uneven size compared with those in the control group. Artificial decidualization was detected in the uteri of the controls, but weakened decidualization response was observed in the BaP-treated groups. BaP significantly reduced the levels of estradiol, progesterone, and their cognate receptors ER and PR, respectively. The expression of several decidualization-related factors, including FOXO1, HoxA10, and BMP2, were altered after BaP treatment. BaP reduced the expression of cluster designation 34 (CD34), which indicated that the decidual angiogenesis was inhibited by BaP treatment. In addition, BaP induced the downregulation of vascular endothelial growth factor A. These data suggest that oral BaP ingestion compromised decidualization and decidual angiogenesis. Our results provide experimental data for the maternal reproductive toxicity of BaP during early pregnancy, which is very important for a comprehensive risk assessment of BaP on human reproductive health.

Development of a core outcome set for epilepsy in pregnancy (E-CORE): a national multi-stakeholder modified Delphi consensus study.

To develop a set of core outcomes for studies on pregnant women with epilepsy. Delphi consensus study. Healthcare professionals, and patient representatives with lived experience of epilepsy in the UK. We used a modified Delphi method and a consultation meeting to achieve consensus. Potential outcomes were identified by systematic review, and were scored using a Likert scale anchored between 1 (least important) and 5 (most important). We included outcomes that scored ≥4 by >70% of participants, and outcomes that scored ≤2 by <15% of participants. Outcomes in studies on epilepsy in pregnancy. Seventy-five healthcare professionals completed the first round, 48 (64%) completed the second round, and 37 (49%) completed the third round of the survey. Twenty-four patient representatives participated. The final core outcome set included 31 outcomes in three domains: neurological, offspring, and obstetric. Outcomes in the neurological domain were seizure control in pregnancy and postpartum, status epilepticus, maternal mortality, drowning, sudden unexpected death in epilepsy, postnatal depression, and quality of life. Offspring domain included congenital abnormalities (major and minor), fetal anticonvulsant syndrome, neurodevelopment, autism disorder, neonatal clinical complications, admission to a neonatal intensive care unit, and anthropometric measurements. The obstetric domain included live birth, stillbirth, miscarriage, ectopic, termination of pregnancy, admission to a high dependency or intensive care unit, breastfeeding, mode of delivery, preterm birth, pre-eclampsia, and eclampsia. Outcomes specific for studies on anti-epileptic drugs (AEDs) included maternal AED toxicity, AED compliance, neonatal withdrawal symptoms, and neonatal haemorrhagic disease. Embedding this core set in future clinical trials will promote the standardisation of reporting to inform clinical practice. A Delphi method identifying core outcomes for epilepsy in pregnancy. Final core set includes 31 outcomes.

Epigenetic regulation of placental glucose transporters mediates maternal cadmium-induced fetal growth restriction.

Cadmium (Cd) is one of the most toxic environmental pollutants that cause fetal malformation and growth restriction. However, the molecular mechanisms underlying maternal Cd toxicity on fetal growth remain largely unknown. Specifically, the role of placental nutrient transporters, including glucose transporters (GLUTs), has been poorly characterized in the etiology of Cd-induced fetal growth restriction (FGR). In the present study, we established a murine model of FGR induced by maternal Cd exposure, and examined the toxic effects of Cd on placental GLUTs. Our results showed that GLUT3 is significantly downregulated in Cd-exposed mouse placentas when compared to the normal ones. Data from bisulfite PCR demonstrated the hypermethylation of the promoter region of GLUT3. However, methylation levels remained unchanged in two major repetitive elements (LINE-1 and IAP) in Cd-exposed placentas. Moreover, DNA methyltransferase (DNMT) 3B and DNMT3L were significantly upregulated in Cd-exposed placentas, and there were no expression changes of DNMT1 and DNMT3A. Collectively, our results suggest that changes in DNMT3B and DNMT3L expressions and site-specific DNA methylation may be involved in the etiology of Cd-induced fetal growth restriction through downregulation of GLUT3.

Adverse effects of Croton urucurana B. exposure during rat pregnancy

Ethnopharmacological relevanceCroton urucurana presents several beneficial pharmacological properties. In Brazil, women who intend to interrupt the pregnancy indiscriminately use extracts of this plant as an abortifacient agent. Aim of studyTo evaluated the effect of aqueous extract of Croton urucurana latex on the maternal-fetal repercussions in rats. MethodsPregnant rats were randomly distributed into four experimental groups: Control=treated with water (vehicle); Treated 200=treated with a dose 200mg/kg; Treated 400=dose 400mg/kg and; and Treated 800=dose 800mg/kg. The rats were orally treated by gavage with Croton urucurana or vehicle (water) during whole pregnancy. At term of pregnancy, all rats were killed to obtain maternal blood and tissues samples and fetal weight and anomaly analyses. ResultsC. urucurana treatment (Treated 400 and Treated 800) showed elevated liver enzymatic activities, reduced fetal body weight and placental efficiency. The Treated 800 group presented increased maternal total protein and cholesterol levels, and heart relative weight. All treated groups presented reduced maternal body weight and food intake, and increased pre-implantation loss rate compared to those of Control group. In addition, the treatment contributed to increased skeletal and visceral anomalies with higher doses. ConclusionCroton urucurana treatment caused maternal toxicity, which contributed for impairment embryo fetal development. These results showed that the indiscriminate use of plants during pregnancy should be avoided to prevent potential risk on maternal health as well as their offspring.

Repeated-doses and reproductive toxicity studies of the monoterpene 1,8-cineole (eucalyptol) in Wistar rats

1,8-cineole (eucalyptol) is widely used as an excipient in the pharmaceutical industry and as a food flavoring agent, thus providing significant potential for human exposure to the compound. We investigated the preclinical toxicity and reproductive toxicity of 1,8-cineole (CIN). In the repeated-doses toxicity study for 50 days, CIN (100, 500 or 1000 mg/kg) did not produce any signs of toxicity or deaths, but affected body weight gain during the first week of treatment. The hematological and biochemical profiles did not show significant differences except for increase in the MCV, platelet and urea levels or reduction in MCHC, MPV and alkaline phosphatase. Histopathological analysis showed weak changes in the lungs, liver, kidneys and uterus. In the reproductive toxicity, CIN (250, 500 or 1000 mg/kg) produced a reduction in body weight in pregnant rats treated during the pre-implantation or organogenesis periods. The highest doses induced a reduction in the mass of fetuses (pre-implantation) and dead fetuses (both periods) of pregnant rats. The results indicate that the treatment by repeated-doses showed occasional alterations in rats of both sexes. However, provide evidence that possibly 1,8-cineole presents maternal and fetal toxicity. This requires more detailed investigation to better characterize the toxic effects of this compound.

Dietary Route of Exposure for Rabbit Developmental Toxicity Studies.

Dietary administration is a relevant route of oral exposure for regulatory toxicity studies of agrochemicals as it mimics potential human intake of the chemical via treated crops and commodities. Moreover, dietary administration of test compounds during a developmental toxicity study can deliver a prolonged and stable systemic exposure to the embryo or fetus at all stages of development. In this study, strategies were employed to optimize rabbit test material consumption via diet. Comparative toxicokinetic profiles of gavage versus dietary administration were evaluated in pregnant or non-pregnant New Zealand White rabbits for 2 novel agrochemicals with different plasma half-lives of elimination (sulfoxaflor, t½ = 13.5 h and halauxifen, t½ = 1 h). Dietary administration of sulfoxaflor resulted in stable 24-h plasma concentrations, whereas gavage administration resulted in a 3-fold fluctuation in plasma levels between Cmax and Cmin Dietary administration of sulfoxaflor resulted in a 2-fold higher nominal and diurnal systemic dose when compared with gavage dosing due to Cmax-related maternal toxicity following gavage. Results with the shorter half-life molecule, halauxifen, were more striking with a 6-fold diurnal fluctuation by the dietary route compared with a 368-fold fluctuation between Cmax and Cmin by gavage. Furthermore, plasma halauxifen was detectable only up to 12 h following gavage but up to 24 h following dietary administration. Finally, the presence of these compounds in fetal blood samples was demonstrated, confirming that dietary exposure is appropriate for achieving fetal exposure. Collectively, the results of these studies support the use of dietary exposure in rabbit developmental toxicity studies.

Fetopathies associated with exposure to angiotensin converting enzyme inhibitor from Tropaeolum majus L.

The prevalence of the use of herbal medicines is on the rise across the world, especially amongst pregnant women. A fact that draws attention is that many species commonly used by pregnant women, including the Tropaeolum majus L. (Tropaeolaceae), also present inhibitory activity on the angiotensin-converting enzyme (ACE). Herein, we have investigated the effects of T. majus extract (HETM) on fetal development, evaluating its relationship with possible ACE inhibitory activity. Pregnant Wistar rats were treated with different HETM doses (3, 30 and 300 mg/kg/day) from gestational days 8–20. Rats were sacrificed on the day 20 of pregnancy and the following parameters were evaluated: clinical symptoms of maternal toxicity; maternal body weight; feed and water intake; maternal liver, kidney, and ovary weights, maternal ACE activity and aldosterone levels, live fetuses mean; dead fetuses percentage, fetus weight, and fetal malformation. All pregnant rats treated with high HETM doses showed significant reduction in plasma ACE activity accompanied by a decrease in serum aldosterone levels. Moreover, significant changes in fetal development were observed, including growth retardation and renal damage after 20 days of gestation. Thus, data presented demonstrate the significant effects of the use of HETM on fetal development during pregnancy.

TGF-β1 monoclonal antibody: Assessment of embryo-fetal toxicity in rats and rabbits.

A humanized monoclonal antibody targeting transforming growth factor β1 (TGF-β1 mab) has been used in development for the treatment of chronic kidney disease. Embryo-fetal development studies were conducted in rats and rabbits using 30 and 25 animals per group, respectively. The TGF-β1 mab was administered subcutaneously to rats at 0, 2, or 50 mg/kg/dose on gestation days (GDs) 6, 10, and 14 and intravenously to rabbits at 0 or 3 mg/kg/dose on GDs 7, 12 to 19, and at 30 mg/kg/dose on GDs 7, 12, 14, 16, and 18. Maternal reproductive endpoints and fetal viability, weight, and morphology were evaluated. There was no indication of maternal or embryo-fetal toxicity in the rat. Effects in the rabbit were limited to the fetus where the 30 mg/kg TGF-β1 mab dose produced a slight decrease in fetal weight and an increase in the incidence of retrocaval ureter and an absent and/or malpositioned kidney/ureter in two fetuses. In conclusion, TGF-β1 mab produced no adverse maternal or embryo-fetal findings in rats when administered ≤50 mg/kg on GDs 6, 10, and 14. TGF-β1 mab did not demonstrate maternal toxicity or embryo-fetal lethality at doses as high as 30 mg/kg when administered on GDs 7, 12, 14, 16, and 18 in rabbits. Fetal growth and morphology were affected only at 30 mg/kg; thus, the no observed adverse effect level was 3 mg/kg in rabbits. The margin of safety for both rats and rabbits was ≥37-fold the clinical exposure level.