Modulation of acrylonitrile-induced embryotoxicity in vitro by glutathione depletion

The effects of glutathione (GSH) depletion on the embryotoxicity of acrylonitrile were assessed in vitro using the rat whole-embryo culture system. Day 10 rat embryos were cultured in rat serum medium for 6 h in the presence of 250 Ml-buthionine-S,R-sulfoximine (BSO), a specific inhibitor of GSH synthesis, to deplete GSH in both embryo and visceral yolk sac. Following pretreatment, conceptuses were cultured for an additional 21 h in the presence of 152, 228, or 304 M acrylonitrile. At the end of the culture period, conceptuses were assessed for survival, growth and development, malformations, and the protein and glutathione content of embryos and yolk sacs were assayed. Acrylonitrile alone produced concentrationrelated and statistically significant decreases in yolk sac diameter, crown-rump length, head length and number of somite pairs, as well as in embryonic and yolk sac proteins. The chemical also caused dysmorphogenesis of the brain and of the caudal extremity, and a concentration-related and statistically significant increase in GSH content in the yolk sac. Pretreatment with BSO significantly enhanced the embryotoxic effects of acrylonitrile. The conceptuses displayed further decreases in functional yolk sac circulation, yolk sac diameter, crown-rump and head length, when compared to either acrylonitrile or BSO alone. The incidence of caudal malformations and the severity of brain malformations produced by acrylonitrile were also increased. Marked decreases in embryonic and yolk sac GSH contents were observed after exposure to BSO alone or in combination with acrylonitrile. Thus, depletion in embryonic and yolk sac GSH by BSO enhanced teratogenic and growth retarding effects of acrylonitrile in vitro, suggesting that GSH plays a critical role in modulating acrylonitrileelicited embryotoxicity.     

褪黑素对苯妥英所致小鼠胚胎体外致畸效应的拮抗作用

采用体外着床后全胚培养模型研究苯妥英诱发的胚胎脂质过氧化和形态异常 ,确定褪黑素 (MT)的胚胎保护作用 .d 8.5的小鼠胚胎经苯妥英单独或与MT联合作用 4 8h后测定胚胎生长 ,形态发育 ,全胚蛋白质含量及脂质过氧化产物 .结果表明苯妥英导致胚胎生长发育迟滞并诱发脂质过氧化产物增高 4倍 .MT 1mmol·L- 1有轻微生长抑制作用 ,但可完全拮抗苯妥英诱发的脂质过氧化作用 ,并降低或完全拮抗苯妥英导致的形态生长发育异常 .表明MT有拮抗苯妥英胚胎致畸效应的作用     

Modulation of phenytoin teratogenicity and embryonic covalent binding by acetylsalicylic acid, caffeic acid, and alpha-phenyl-N-t-butylnitrone: implications for bioactivation by prostaglandin synthetase

Teratogenicity of the anticonvulsant drug phenytoin is thought to involve its bioactivation by cytochromes P-450 to a reactive arene oxide intermediate. We hypothesized that phenytoin also may be bioactivated to a teratogenic free radical intermediate by another enzymatic system, prostaglandin synthetase. To evaluate the teratogenic contribution of this latter pathway, an irreversible inhibitor of prostaglandin synthetase, acetylsalicylic acid (ASA), 10 mg/kg intraperitoneally (ip), was administered to pregnant CD-1 mice at 9:00 AM on Gestational Days 12 and 13, 2 hr before phenytoin, 65 mg/kg ip. Other groups were pretreated 2 hr prior to phenytoin administration with either the antioxidant caffeic acid or the free radical spin trapping agent alpha-phenyl-N-t-butylnitrone (PBN). Caffeic acid and PBN were given ip in doses that respectively were up to 1.0 to 0.05 molar equivalents to the dose of phenytoin. Dams were killed on Day 19 and the fetuses were assessed for teratologic anomalies. A similar study evaluated the effect of ASA on the in vivo covalent binding of radiolabeled phenytoin administered on Day 12, in which case dams were killed 24 hr later on Day 13. ASA pretreatment produced a 50% reduction in the incidence of fetal cleft palates induced by phenytoin (p less than 0.05), without significantly altering the incidence of resorptions or mean fetal body weight. Pretreatment with either caffeic acid or PBN resulted in dose-related decreases in the incidence of fetal cleft palates produced by phenytoin, with maximal respective reductions of 71 and 82% at the highest doses of caffeic acid and PBN (p less than 0.05). Caffeic acid and PBN also significantly reduced the incidence of fetal resorptions produced by phenytoin, but not the fetal weight loss. In viable embryos, ASA pretreatment reduced the covalent binding of phenytoin to embryonic protein by 43% (p less than 0.05). Binding of phenytoin to embryonic resorptions was equally high with and without ASA pretreatment, and within each treatment group was 3- to 10-fold higher than that in the respective placentas and associated viable embryos (p less than 0.05). These results suggest that prostaglandin synthetase may contribute to the enzymatic bioactivation of phenytoin to a teratogenic free radical intermediate.     

Distribution of silver nanoparticles in pregnant mice and developing embryos

Abstract

The objective of this study was to evaluate the distribution of silver nanoparticles (NPs) in pregnant mice and their developing embryos. Silver NPs (average diameter 50 nm) were intravenously injected into pregnant CD-1 mice on gestation days (GDs) 7, 8, and 9 at dose levels of 0, 35, or 66 μg Ag/mouse. Mice were euthanised on GD10, and tissue samples were collected and analysed for silver content. Compared with control animals injected with citrate buffer vehicle, silver content was significantly increased (p < 0.05) in nearly all tissues from silver NP-treated mice. Silver accumulation was significantly higher in liver, spleen, lung, tail (injection site), visceral yolk sac, and endometrium compared with other organs from silver NP-treated mice. Furthermore, silver NPs were identified in vesicles in endodermal cells of the visceral yolk sac. In summary, the results demonstrated that silver NPs distributed to most maternal organs, extra-embryonic tissues, and embryos, but did not accumulate significantly in embryos.     

Section Review Oncologic,Endocrine & Metabolic: Farnesyl-protein transferase inhibitors in early development

Over the last decade the underlying mechanisms that cause tu-mourigenesis are progressively being elucidated. One potential mechanism includes the participation of farnesyl-protein transferase in promoting the effects of oncogenic forms of ras. Membrane localisation of Ras is essential for ras-induced tumour formation. Farnesyl-protein transferase catalyses the attachment of farnesyl to the carboxyl terminal cysteine residue of Ras. Genetic evidence indicates that unprenylated oncogenic Ras is soluble, cannot promote tumourigenesis and is apparently not deleterious to the cell. Several inhibitors of farnesyl-protein transferase are currently being tested in animal models of tumourigenesis. This review will focus on compounds that are presently being developed by Eisai, Banyu, Bristol-Myers Squibb, Merck, Roche/Genentech/University of Texas, Schering-Plough and the University of Pittsburgh.     

Variable in vivo embryoprotective role for ataxia-telangiectasia-mutated against constitutive and phenytoin-enhanced oxidative stress in atm knockout mice.

Knockout mice lacking the ataxia-telangiectasia-mutated (Atm) protein exhibit impaired detection and repair of DNA damage and increased embryopathies from ionizing radiation in vivo, and vehicle or phenytoin in embryo culture. Here we determined if Atm-deficient mice are more susceptible in vivo to phenytoin embryopathies. Wild-type (+/+) or heterozygous (+/-) Atm knockout dams were mated with +/- males, pregnant dams were treated with phenytoin (65 mg/kg ip) or its vehicle, and resorptions and fetuses were genotyped and characterized. This strain proved resistant to phenytoin-initiated cleft palates but not to other spontaneous and phenytoin-enhanced embryopathies. With vehicle-treated +/- dams, fetal body weight was lower in homozygous Atm-null (-/-) fetuses compared to +/- and +/+ littermates (p < 0.05). Phenytoin enhanced this Atm-dependent embryopathic pattern (p < 0.05). It also enhanced DNA oxidation in -/- Atm-deficient embryos compared to its +/- Atm-deficient (p < 0.001) and +/+ Atm-normal (p < 0.001), phenytoin-exposed littermates and to its -/- vehicle controls (p < 0.01). Postpartum lethality was greater in both +/- and -/- Atm-deficient fetuses compared to +/+ littermates, independent of treatment (0.05 < p < 0.1). By maternal genotype, +/- Atm-deficient dams had fewer implantations than +/+ dams, independent of treatment, and phenytoin decreased litter size (p < 0.05). Conversely, phenytoin-exposed +/+ fetuses were more likely than -/- littermates to die in utero (p < 0.05), and in +/+ dams fetal resorptions and postpartum lethality were variably higher and enhanced by phenytoin (p < 0.05). Despite variable actions in vivo, the embryoprotective effects of Atm suggest a role for reactive oxygen species and oxidative DNA damage in some spontaneous and phenytoin-enhanced embryopathies.     

Increased Susceptibility to Phenytoin Teratogenicity: Excessive Generation of Reactive Oxygen Species or Impaired Antioxidant Defense?

Phenytoin is a human and animal teratogen. Accumulating evidence suggests that the teratogenicity is associated with a potential of phenytoin to cause embryonic cardiac arrhythmia and resultant generation of toxic reactive oxygen species via hypoxia-reoxygenation mechanisms. The A/J mouse is more susceptible to phenytoin teratogenicity than other mouse strains. The aim of this study was to investigate whether A/J mice have other antioxidant enzyme activities than C57BL/6J and CD-1 mice. Also, strain differences in phenytoin effects on embryonic heart rate and rhythm were determined. Another objective was to determine whether a spin trapping agent with capacity to capture reactive oxygen species alter the developmental toxicity of phenytoin. Treatment with this agent resulted in a marked decrease in phenytoin teratogenicity, which supports the idea that reactive oxygen species are important mediators for the teratogenic action of phenytoin. The A/J mice embryos were most susceptible to the adverse cardiac effects of phenytoin and had the highest activity of superoxide dismutase and glutathione peroxidase, while the activity of catalase was the same in embryos of the three different strains. The high activities of antioxidant enzymes in the A/J stain indicate that the sensitivity to develop malformations is caused by excessive arrhythmia-related generation of reactive oxygen species rather than impaired antioxidant defense.     

Embryotoxicity of human sera from patients treated with isotretinoin

Sera of 20 patients treated with 20–40 mg isotretinoin/day were tested for embryotoxicity potential. For each patient, the first sample was taken before treatment (control sample) and the second was taken 2 months after the start of treatment (treated sample). Six embryos displaying six or seven pairs of somites were cultured for 26 hr in each serum sample, when sufficient serum was available. No deaths were observed in the control sample, whereas dead embryos (6%) were observed in the treated sample. The rates of malformed embryos were 13 and 81% in the control and in the treated sample, respectively. The most frequent abnormalities affected the cephalic neural tube, the branchial bars, the yolk sac circulation and the caudal neural tube. Growth and differentiation were significantly decreased in the treated sample. The concentrations of isotretinoin and of two metabolites (trans-retinoic acid and 4-oxo-isotretinoin) were measured in 12 sera. A correlation between embryotoxicity and concentration was established for two of the chemicals. Modulation of the embryotoxicity by drug-induced changes in the serum cannot be excluded.     

用全胚胎培养方法评价重铬酸钾对大鼠和小鼠胚胎的发育毒性

采用植入后全胚胎培养方法研究重铬酸钾对大,小鼠胚胎的发育毒性. 结果表明,重铬酸钾在1.0和2.5 mg·L^-1以上时分别可致大,小鼠胚胎体长,头长,卵黄囊直径及胚胎干重等各项指标明显低于对照组,同时观察到大,小鼠胚胎脑,神经管和体屈等发育迟缓,组织光镜可见胚胎神经管上皮变薄,细胞排列不规则. 以上结果均呈明显的剂量 反应关系,表明重铬酸钾体外对大,小鼠胚胎具有明显的发育毒性,且大鼠比小鼠敏感.     

Embryotoxicity elicited by inhibition of gamma-glutamyltransferase by Acivicin and transferase antibodies in cultured rat embryos

Acivicin (also known as AT-125) and IgG isolated from goat anti-gamma-glutamyltransferase antiserum were used to inhibit the activity of gamma-glutamyltransferase (GGT, EC 2.3.2.2) in rat conceptuses cultured from Days 10 to 11 of gestation. Inhibition of GGT by either Acivicin or anti-GGT IgG produced embryotoxicity and malformations, although each compound produced a unique spectrum of effects. Acivicin, at an initial concentration in the culture medium of 5 microM, produced a marked decrease in yolk sac vasculature and was associated with embryonic malformations such as neural tube necrosis, microophthalmia, and cephalic edema after 24 hr exposure. These malformations were accompanied by significant decreases in both embryonic and yolk sac protein, yolk sac GGT activity, as well as embryonic glutathione (GSH) levels. In contrast, anti-GGT IgG produced no apparent effects on yolk sac vasculature or protein after exposure of conceptuses to an initial concentration of 50 micrograms IgG/ml culture medium, even though equal inhibition of yolk sac GGT (30%) was achieved by each inhibitor. Exposure to IgG (50 micrograms/ml) for 24 hr was associated with decreased embryonic protein; decreased levels of GSH in the embryo were observed after both 3 and 24 hr. The dichotomy of effects on the yolk sac by the two compounds indicates that Acivicin produced these effects by mechanisms other than by GGT inhibition alone. These results demonstrate that inhibition of GGT in rat embryos undergoing organogenesis can elicit embryotoxic effects and produce alterations in GSH levels. The capacity of the anti-GGT antibody to inhibit the GGT activity in the yolk sac (while having no apparent effect on yolk sac morphology), and yet influence the embryo by decreasing protein and GSH levels, underscores the important role of the yolk sac during the highly sensitive stages of organogenesis.     

Comparison of the embryotoxic effects of saporin, agrostin (type 1 ribosome-inactivating proteins) and ricin (a type 2 ribosome-inactivating protein).

The effects of two type I ribosome-inactivating proteins, saporin and agrostin, and the type 2 ribosome-inactivating protein ricin and its constituent A and B chains, on the development of cultured mouse embryos, were investigated. Saporin and agrostin had similar embryotoxicity which was approximately 10(5) times weaker than that of ricin and its A and B chains, and the embryotoxicity of saporin and agrostin increased gradually with the dosage. In contrast, there was an abrupt rise in embryotoxictiy of ricin-A chain and B chain as the dose was raised from 10 to 20 ng x ml(-1). Saporin and agrostin did not affect the heart-beat and otic placode, but at 10 ng x ml(-1) ricin and 40 ng x ml(-1) ricin-A chain and B chain, all of the treated embryos exhibited abnormalities in heart-beat, yolk sac circulation, body axis, optic placode, otic placode, forelimb buds, branchial apparatus and cranial neural tube.     

Dose-response relationship of cadmium embryotoxicity in cultured mouse embryos

Mouse embryos were exposed in vitro to 1.2 to 2.2 μM cadmium, and effects on embryotoxicity were examined after 39 h of culture. Teratogenic responses similar to in vivo were obtained at 1.2 to 2.2 μM with concomitant reduction in embryonic protein, while embryo deaths were increased from 13.8 to 93.3% at 2.0 to 2.2 μM. The response data of both teratogenicity and growth parameters, including embryonic protein, head lenght, crown-rump lenght, somite number, and protein and diameter of yolk sac, were acceptably fitted to a cadmium is a critical parameter in the manifestation of teratogenic potential, (b) as an estimation of interference in the growth of embryos, embryonic protein is one of the most sensitive endpoints while somite number is an insensitive criterion, and (c) a linear log-probit regression is applicable to the analyses of embryotoxicity data, including growth parameters in whole-embryo culture systems.     

Effects of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate on phenytoin-induced embryopathy in mice

The anticonvulsant drug phenytoin may be cooxidized during prostaglandin biosynthesis to a reactive free radical intermediate capable of exerting embryopathic effects. Since 12-O-tetradecanoylphorbol-13-acetate (TPA), a potent tumor promoter, activates the enzymatic release of arachidonic acid, thereby initiating prostaglandin synthesis, the potential teratological synergism between these two compounds was investigated. Pregnant CD-1 mice were given a fixed dose of phenytoin, 65 mg/kg intraperitoneally (ip), on Gestational Days 12 and 13, followed 2 hr later by varying doses of TPA, 0.2 to 2000 micrograms/kg ip. The dams were killed on Day 19 and fetuses were examined for anomalies. TPA post-treatment with doses of 2 to 200 micrograms/kg produced a TPA dose-related increase in maternal lethality of up to 100%, compared with no lethality in dams given TPA or phenytoin alone. Subsequent studies therefore were restricted to TPA doses between 0.2 and 20 micrograms/kg. TPA 20 micrograms/kg caused a threefold increase (p = 0.11) in the incidence of phenytoin-induced cleft palates, which likely was an underestimate due to the extremely high (97%) incidence of fetal resorptions. With lower TPA doses of 0.2 to 20 micrograms/kg, the incidence of fetal resorptions in animals treated with both phenytoin and TPA increased in a TPA dose-related manner, to over twofold (p less than 0.05), compared with phenytoin controls. Postpartum fetal lethality was enhanced similarly by the combination treatment, reaching a maximum of 100% (p less than 0.05). Lower doses of TPA also significantly enhanced the fetal weight loss in phenytoin-treated mice, while in contrast, TPA alone significantly increased fetal body weight compared with vehicle-treated controls. In animals treated with only TPA, the incidence of embryopathy generally was either comparable to controls or significantly less than that in phenytoin controls. These data indicate that TPA can potentiate phenytoin-induced embryopathy, possibly through a mechanism involving bioactivation by prostaglandin synthetase.     

Dose-response relationship of cadmium embryotoxicity in cultured mouse embryos

Mouse embryos were exposed in vitro to 1.2 to 2.2 microM cadmium, and effects on embryotoxicity were examined after 39 h of culture. Teratogenic responses similar to in vivo were obtained at 1.2 to 2.2 microM with concomitant reduction in embryonic protein, while embryo deaths were increased from 13.8 to 93.3% at 2.0 to 2.2 microM. The response data of both teratogenicity and growth parameters, including embryonic protein, head length, crown-rump length, somite number, and protein and diameter of yolk sac, were acceptably fitted to a linear log-probit regression. These results suggest that (a) In chronic exposure conditions, the concentration of cadmium is a critical parameter in the manifestation of teratogenic potential, (b) as an estimation of interference in the growth of embryos, embryonic protein is one of the most sensitive endpoints while somite number is an insensitive criterion, and (c) a linear log-probit regression is applicable to the analyses of embryotoxicity data, including growth parameters in whole-embryo culture systems.     

Comparison of the Embryotoxic Effects of Saporin,Agrostin (Type 1 Ribosome‐Inactivating Proteins) and Ricin (a Type 2 Ribosome‐Inactivating Protein

Abstract: The effects of two type I ribosome‐inactivating proteins, saporin and agrostin, and the type 2 ribosome‐inactivating protein ricin and its constituent A and B chains, on the development of cultured mouse embryos, were investigated. Saporin and agrostin had similar embryotoxicity which was approximately 10⁵ times weaker than that of ricin and its A and B chains, and the embryotoxicity of saporin and agrostin increased gradually with the dosage. In contrast, there was an abrupt rise in embryotoxictiy of ricin‐A chain and B chain as the dose was raised from 10 to 20 ng ml^?1. Saporin and agrostin did not affect the heart‐beat and otic placode, but at 10 ng ml^?1 ricin and 40 ng ml^?1 ricin‐A chain and B chain, all of the treated embryos exhibited abnormalities in heart‐beat, yolk sac circulation, body axis, optic placode, otic placode, forelimb buds, branchial apparatus and cranial neural tube.     

Enhanced NADPH oxidases and reactive oxygen species in the mechanism of methanol-initiated protein oxidation and embryopathies in vivo and in embryo culture

Methanol (MeOH) teratogenicity in rodents may be mediated in part by reactive oxygen species (ROS), the source of which is unknown. To determine if MeOH enhances embryonic ROS-producing NADPH oxidases (NOXs), p22phox mRNA and protein and oxidatively damaged protein were measured in gestational day 12 MeOH-exposed CD-1 mouse embryos with or without pretreatment with the free radical spin trap phenylbutylnitrone (PBN) or the NOX inhibitor diphenyleneiodonium chloride (DPI). MeOH exposure upregulated p22phox mRNA and protein expression, and enhanced protein oxidation, within 3–6 h. Compared to embryos exposed to MeOH alone, PBN and DPI pretreatment decreased MeOH-enhanced p22phox mRNA expression, DPI but not PBN blocked p22phox protein expression, and both blocked protein oxidation. To assess developmental relevance, mouse embryos were exposed in culture for 24 h to MeOH or vehicle with or without pretreatment with PBN, DPI, or the prostaglandin H synthase (PHS) inhibitor eicosatetraynoic acid (ETYA), and evaluated for abnormalities. ETYA did not prevent MeOH embryopathies, despite blocking phenytoin embryopathies (ROS-initiating positive control), precluding bioactivation of MeOH or its metabolites by PHS. Concentration-dependent MeOH embryopathies were blocked by both DPI and PBN pretreatment, suggesting that enhanced embryonic NOX-catalyzed ROS formation and oxidative stress may contribute to the mechanism of MeOH embryopathies.     

Protection of rat embryos in culture against the embryotoxicity of acrolein using exogenous glutathione

The aldehyde acrolein is embryotoxic in vivo and in vitro. Since acrolein is reactive towards thiols, glutathione was evaluated for its protective effects against the in vitro embryotoxicity of acrolein. Day 10 rat embryos were cultured in the presence of acrolein and glutathione, either concurrently or sequentially, and evaluated for embryo deaths, malformations, growth retardation, and content of glutathione and protein. Acrolein, added alone at the initiation of the culture period, was embryolethal to 64 and 100% of the embryos at 120 and 160 microM respectively. At acrolein concentrations of 80 and 120 microM, 50 and 100%, respectively, of the surviving embryos were malformed. In addition, both of these concentrations of acrolein produced growth retardation manifested by significant decreases in the yolk sac diameter, crown-rump and head lengths, number of somites, and morphological score. Concurrent exposure to 100 or 500 microM glutathione markedly protected embryos against all of these effects. To study the mechanism of the protective effect of glutathione against the embryotoxicity of acrolein, the effects of sequential addition of acrolein and glutathione were determined. When rat embryos were cultured in the presence of acrolein for 2 hr prior to exposure to glutathione, even 500 microM glutathione could not offer any protection against the embryolethality, teratogenicity, and growth retardation induced by acrolein. However, a 6-hr preincubation with 500 microM glutathione, prior to exposure to acrolein (in the absence of exogenous glutathione), significantly decreased the incidence of embryo deaths at 160 microM acrolein and brought the number of deaths and malformations among embryos exposed to 120 microM acrolein down to a level not significantly different from control; unlike the embryos exposed concurrently to acrolein and glutathione, however, the sequential treatment with glutathione and acrolein did not protect against growth retardation. While there were some changes in the total glutathione and protein content of embryos and yolk sacs with acrolein exposure, none of the treatments had any overall effect on the glutathione concentration per mg protein. Thus, exogenous glutathione can protect against the in vitro embryotoxicity of acrolein. We propose that this protection is mediated in part by a direct interaction between glutathione and acrolein, added concurrently to the serum medium, and in part by an indirect effect on the embryo of glutathione added prior to acrolein.     

Folic acid and pantothenic acid protection against valproic acid-induced neural tube defects in CD-1 mice

In utero exposure to valproic acid (VPA) during pregnancy is associated with an increased risk of neural tube defects (NTDs). Although the mechanism by which VPA mediates these effects is unknown, VPA-initiated changes in embryonic protein levels have been implicated. The objectives of this study were to investigate the effect of in utero VPA exposure on embryonic protein levels of p53, NF-kappaB, Pim-1, c-Myb, Bax, and Bcl-2 in the CD-1 mouse. We also evaluated the protective effects of folic acid and pantothenic acid on VPA-induced NTDs and VPA-induced embryonic protein changes in this model. Pregnant CD-1 mice were administered a teratogenic dose of VPA prior to neural tube closure and embryonic protein levels were analyzed. In our study, VPA (400 mg/kg)-induced NTDs (24%) and VPA-exposed embryos with an NTD showed a 2-fold increase in p53, and 4-fold decreases in NF-kappaB, Pim-1, and c-Myb protein levels compared to their phenotypically normal littermates (P<0.05). Additionally, VPA increased the ratio of embryonic Bax/Bcl-2 protein levels (P<0.05). Pretreatment of pregnant dams with either folic acid or pantothenic acid prior to VPA significantly protected against VPA-induced NTDs (P<0.05). Folic acid also reduced VPA-induced alterations in p53, NF-kappaB, Pim-1, c-Myb, and Bax/Bcl-2 protein levels, while pantothenic acid prevented VPA-induced alterations in NF-kappaB, Pim-1, and c-Myb. We hypothesize that folic acid and pantothenic acid protect CD-1 embryos from VPA-induced NTDs by independent, but not mutually exclusive mechanisms, both of which may be mediated by the prevention of VPA-induced alterations in proteins involved in neurulation.     

Capsaicin prevents ethanol-induced teratogenicity in cultured mouse whole embryos

Prenatal exposure to alcohol promotes the level of reactive oxygen species within embryos and results in developmental disorders. In this study, we investigated the effect of capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide), the major pungent ingredient in red peppers, on ethanol-induced teratogenicity in mouse embryos (embryonic days 8.5-10.5). In response to ethanol administration (1.0 microl/ml), developmental parameters such as yolk sac circulation, allantois, heart, hindbrain, midbrain, forebrain, otic and optic systems, branchial bar, olfactory system, forelimb, hindlimb, and somites decreased significantly in comparison with those of control group (p<0.05). However, the concurrent administration of capsaicin (1 x 10(-8) microg/ml or 1 x 10(-7) microg/ml) and ethanol significantly ameliorated most of the morphological scores excepting yolk sac circulation and hindlimb scores (p<0.05). Furthermore, the levels of superoxide dismutase activity and cytoplasmic glutathione peroxidase and phospholipid hydroperoxide glutathione peroxidase mRNAs in the ethanol-treated embryos recovered to the levels observed in control embryos by capsaicin co-administration. These results indicate that capsaicin has a protective effect against ethanol-induced teratogenicity via an antioxidative activity.