ascorbic-acid and nitrofen

Many studies suggest a role for antioxidants in the prevention of lung hypoplasia in nitrofen-induced rat models with congenital diaphragmatic hernia (CDH). This study investigates the oxidative status and the histological outcome of prenatal administration of vitamins E and C with synergistic effect, and effect of N-acetylcysteine (NAC) to improve lung maturation of nitrofen-induced rats.. CDH was induced by maternal administration of a single oral dose of nitrofen on day 9.5 of gestation, and the Sprague-Dawley rats were randomly divided into five groups: nitrofen (N), nitrofen + vitamin C (NC), nitrofen + vitamin E (NE), nitrofen + vitamin C + vitamin E (NCE) and nitrofen + NAC (NNAC). A control group in which only vehicle was administered was included. Cesarean section was performed on day 21. Body weight (BW) and total lung weight (LW) of all fetuses with CDH were recorded; lung histological evaluation was performed, and protein content of lungs, determination of thiobarbituric acid reactive substances, and the protein carbonyls in tissue samples were determined.. A total of 133 rat fetuses with CDH were investigated. The body weight and the lung weight of fetuses of all groups that were exposed to nitrofen were significantly decreased than of the control group (P < 0.05). The animals exposed to nitrofen with different antioxidants showed increased protein levels in lung tissue. However, in the NCE and the NNAC groups, protein levels were significantly increased than in the others. Malondialdehyde levels significantly decreased in the NCE and the NNAC groups when compared with the NC and the NE groups. In addition, the NCE and NNAC groups decreased protein oxidation to control levels, and no significant difference was observed between control and these two antioxidants groups. The N, NC, NE and NNAC groups showed minimal improvement in lung histology; the NCE groups showed the most improvement in lung histology when compared with the other nitrofen plus antioxidant groups.. Prenatal administration of NAC and vitamin E in combination with vitamin C represented the best effects to avoid oxidative damage and protein content of the lungs in rat pups with CDH at birth.

Topics: Acetylcysteine; Animals; Antioxidants; Ascorbic Acid; Disease Models, Animal; Drug Synergism; Female; Fetus; Free Radical Scavengers; Hernia, Diaphragmatic; Hernias, Diaphragmatic, Congenital; Lipid Peroxidation; Lung; Lung Diseases; Male; Maternal-Fetal Exchange; Pesticides; Phenyl Ethers; Pregnancy; Proteins; Rats; Rats, Sprague-Dawley; Thiobarbituric Acid Reactive Substances; Vitamin E

Congenital diaphragmatic hernia (CDH) is a developmental anomaly that results in significant mortality and morbidity. The underlying etiology is poorly understood. Insights will arise from an understanding of the mechanisms by which the teratogen nitrofen induces CDH in rodent models. In this study, we use in vitro cell assays in conjunction with whole animal rodent studies to test hypotheses regarding nitrofen's mechanism of action. The first component examined the interaction of nitrofen with various aspects of the retinoid signaling pathway including uptake proteins, binding proteins, receptors, conversion, and degradation enzymes. The second component examined the interactions of nitrofen and vitamins A, C, and E to test the hypothesis that nitrofen was functioning as an antioxidant to interfere with retinoid signaling. Third, we performed a series of experiments examining the interaction of nitrofen and thyroid signaling. Collectively, the data suggest that the primary aspect of retinoid signaling affected by nitrofen is via inhibition of the rate-limiting enzymes controlling retinoic acid synthesis. Retinoid signaling perturbations do not appear to involve oxidative effects of nitrofen. Any substantial roles of nitrofen-induced perturbations of thyroid hormone signaling or receptor function are not supported.

Topics: Animals; Antioxidants; Ascorbic Acid; Cell Line, Tumor; Drug Interactions; Embryonic Structures; Hernia, Diaphragmatic; Hernias, Diaphragmatic, Congenital; Mice; Phenyl Ethers; Rats; Rats, Sprague-Dawley; Receptors, Thyroid Hormone; Retinoids; Signal Transduction; Teratogens; Thyroid Hormones; Vitamin A; Vitamin E

Nitrofen (2,4-dichloro-4 -nitrodiphenyl ether), a teratogen with oxidant properties, induces congenital diaphragmatic hernia (CDH) with lung hypoplasia and delayed lung development and maturation in rat embryos. Several phenotypic features of the alveolar epithelium including surfactant proteins A and B synthesis and its regulation by transcription factors are reproduced in cultured human H441 pneumocytes. The aim of the present study was to test whether vitamins A, E and C with anti-oxidant properties were able to recover the expression of such regulators in an in vitro setting.. Cultured human H441 pneumocytes were treated with nitrofen with or without additional exposure to vitamins A, E and C. Thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3-beta (HNF-3beta) and hepatocyte nuclear factor 3-beta surfactant protein B (SP-B) mRNAs were measured by real-time polymerase chain reaction (RT-PCR). The cells were also immunohistochemically stained for assessment of proliferation (PCNA) and apoptosis (bis-benzimide) status and SP-B and TTF-1 protein expressions. Results were compared by ANOVA with a significant threshold of 5%.. Nitrofen severely decreased TTF-1, HNF-3beta and SP-B mRNA expression by H441 pneumocytes in culture. Addition of vitamin E normalized the levels of the three transcripts, while vitamin A normalized only those of TTF-1 and SP-B mRNA. Vitamin C was significantly beneficial only for SP-B transcript. Nitrofen decreased proliferation and TTF-1 and SP-B protein expressions with no apparent effect on apoptosis. Additional exposure to vitamins A, C or E rescued near normal values.. The changes induced by nitrofen in cultured H441 human pneumocytes are reverted in part by anti-oxidant vitamins by upregulating TTF-1, HNF-3beta and SP-B and stimulating proliferation and maturity in nitrofen-treated cells. These effects of anti-oxidant vitamins could be of some interest for developing new transplacental therapeutic strategies aimed at improving lung development and maturation in fetuses with CDH.

Topics: Ascorbic Acid; Cells, Cultured; DNA Primers; DNA-Binding Proteins; Hepatocyte Nuclear Factor 3-beta; Humans; Lung; Phenyl Ethers; Polymerase Chain Reaction; Pulmonary Surfactant-Associated Protein B; Transcription Factors; Vitamin A; Vitamin E

Oxidant herbicide nitrofen (2,4-dichloro-4'-nitrodiphenyl ether) induces in rat embryos congenital diaphragmatic hernia (CDH) with lung hypoplasia. The present study aims at examining whether antioxidant vitamins A, E, and C reverse the effects of the teratogen in the lungs of exposed rats and how they modify the expression of molecular regulators known to be involved in their pathogenesis.. Wet lung weight-body weight ratio, total DNA, and total protein were determined. Thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3beta (HNF-3beta), and surfactant protein B (SP-B) proteins were measured by immunoblot assay in lung homogenates from rat fetuses exposed in utero to either nitrofen 100 mg intragastrically or vehicle. The coexpression of these factors in the alveolar epithelium was demonstrated by immunohistochemistry. The effects of the addition of vitamins A, C, and E were assessed by comparison with analysis of variance.. Nitrofen decreased lung weight, total DNA, and total protein. The addition of antioxidant vitamins had no effect on lung weight, but increased DNA and protein contents. TTF-1, HNF-3beta, and SP-B proteins were decreased in lung homogenates of exposed rats with CDH. The addition of antioxidant vitamins nearly normalized these values.. The effects of nitrofen in fetal rat lungs are reversed in part by antioxidant vitamins by upregulating the expression of TTF-1, HNF-3beta, and SP-B. This approach could help to develop transplacental prenatal interventions for CDH.

Topics: Animals; Antioxidants; Ascorbic Acid; Female; Hepatocyte Nuclear Factor 3-beta; Herbicides; Hernia, Diaphragmatic; Lung; Lung Diseases; Nuclear Proteins; Organ Size; Peptide Fragments; Phenyl Ethers; Pregnancy; Proteolipids; Rats; Rats, Sprague-Dawley; Respiratory System Abnormalities; Thyroid Nuclear Factor 1; Transcription Factors; Up-Regulation; Vitamin A; Vitamin E; Vitamins

Nitrofen induces heart hypoplasia together with congenital diaphragmatic hernia (CDH) in rats. Intracellular oxidative stress might be one of the mechanisms of action of the teratogen, and vitamin A has been shown to reverse in part these effects when administered simultaneously or shortly after it. This study aims at testing the hypothesis that vitamin A and other antioxidant vitamins, such as E and C, could improve myocardial development even when administered late in gestation, a likely useful period for prenatal medication.. Time-mated Sprague-Dawley female rats were exposed to either vehicle (control) or 100 mg of nitrofen (experimental) on day 9.5 of gestation. In 3 additional groups, the animals were exposed to vitamin A (total 15000 IU), vitamin E (total 150 IU), or vitamin C (total 150 IU) on days 16, 17, and 18. The fetuses were recovered on day 21, and randomly selected hearts of those with CDH were processed for histologic studies (hematoxylin-eosin and periodic acid-Schiff stainings), DNA and protein contents, and ki-67 (proliferation) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin end labeling (apoptosis) studies. The differences among groups were assessed by analysis of variance with Bonferroni/Dunn post hoc tests and a threshold of significance of P < .05.. Nitrofen induced heart hypoplasia in terms of decreased heart/body weight, cell mass (less DNA and protein), and proportion of proliferating cells with increased apoptosis. Vitamin C alleviated weight hypoplasia and the 3 vitamins were able to restore cell mass and to reestablish near-normal figures of proliferation and apoptosis.. Antioxidant vitamins A, E, and C given late in gestation alleviate heart hypoplasia that accompanies CDH in the rat model. This timing suggests that the beneficial effects are exerted on the maturational phase of development.

Topics: Animals; Apoptosis; Ascorbic Acid; Disease Models, Animal; DNA; Female; Fetal Heart; Heart Defects, Congenital; Hernia, Diaphragmatic; Hernias, Diaphragmatic, Congenital; In Situ Nick-End Labeling; Oxidants; Phenyl Ethers; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Sprague-Dawley; Teratogens; Vitamin A; Vitamin E; Vitamins

One of the mechanisms of action of nitrofen is intracellular oxidative stress. It is therefore likely that anti-oxidant agents can counteract its action. The aim of this study was to examine whether vitamin C mitigates the effects of nitrofen on the proliferation/apoptosis balance and functional maturation of cultured human pneumocytes.. Lung aCa type II pneumocytes (NIH-H441) in culture were exposed to 1.5 microM of nitrofen alone or followed 48 h later by 60 microM of vitamin C. The culture dishes were recovered at 72 h for immunohistochemical (PCNA for proliferation, bis-benzimide for apoptosis, anti-SpB and anti-TTF-1 antibodies for SpB and TTF-1 assessment) and molecular studies. Real-time PCR was used to quantitate TTF-1 RNAm, with S26 as internal control. ANOVA or Kruskall-Wallis with appropriate post hoc tests were used for comparison with p<0.05 as threshold of significance.. Nitrofen decreased proliferation and TTF/1 and SpB expression with no apparent affect on apoptosis. Additional exposure to vitamin C reverted these effects. Furthermore, nitrofen decreased TTF/1 mRNA and vitamin C tended to rescue normal values.. Vitamin C partially rescued proliferation and maturity in nitrofen-treated human pneumocytes. The likely beneficial influence of this prenatal anti-oxidant medication should be further investigated.

Topics: Antioxidants; Apoptosis; Ascorbic Acid; Cell Division; Cells, Cultured; Herbicides; Humans; Lung; Nuclear Proteins; Oxidants; Oxidative Stress; Phenyl Ethers; Pulmonary Surfactant-Associated Protein B; Thyroid Nuclear Factor 1; Transcription Factors