Perturbations in choline metabolism cause neural tube defects in mouse embryosin vitro
| Autor: | Steven H. Zeisel, Mei Heng Mar, T. W. Sadler, Melanie C. Fisher |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Central Nervous System
Phosphorylcholine Models Neurological Biology Ceramides Biochemistry Choline Diglycerides Embryonic and Fetal Development Mice chemistry.chemical_compound Phosphatidylcholine Genetics medicine Animals Molecular Biology Cells Cultured Phosphocholine Phosphatidylethanolamine Phospholipid Ethers Deanol Gastrula Embryo Mammalian Choline acetyltransferase Acetylcholine Sphingomyelins Betaine chemistry Phosphatidylethanolamine N-methyltransferase Phosphatidylcholines lipids (amino acids peptides and proteins) Sphingomyelin Biotechnology medicine.drug |
| Zdroj: | The FASEB Journal. 16:619-621 |
| ISSN: | 1530-6860 0892-6638 |
| Popis: | A role for choline during early stages of mammalian embryogenesis has not been established, although recent studies show that inhibitors of choline uptake and metabolism, 2-dimethylaminoethanol (DMAE), and 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3), produce neural tube defects in mouse embryos grown in vitro. To determine potential mechanisms responsible for these abnormalities, choline metabolism in the presence or absence of these inhibitors was evaluated in cultured, neurulating mouse embryos by using chromatographic techniques. Results showed that 90%-95% of 14C-choline was incorporated into phosphocholine and phosphatidylcholine (PtdCho), which was metabolized to sphingomyelin. Choline was oxidized to betaine, and betaine homocysteine methyltransferase was expressed. Acetylcholine was synthesized in yolk sacs, but 70 kDa choline acetyltransferase was undetectable by immunoblot. DMAE reduced embryonic choline uptake and inhibited phosphocholine, PtdCho, phosphatidylethanolamine (PtdEtn), and sphingomyelin synthesis. ET-18-OCH3 also inhibited PtdCho synthesis. In embryos and yolk sacs incubated with 3H-ethanolamine, 95% of recovered label was PtdEtn, but PtdEtn was not converted to PtdCho, which suggested that phosphatidylethanolamine methyltransferase (PeMT) activity was absent. In ET-18-OCH3 treated yolk sacs, PtdEtn was increased, but PtdCho was still not generated through PeMT. Results suggest that endogenous PtdCho synthesis is important during neurulation and that perturbed choline metabolism contributes to neural tube defects produced by DMAE and ET-18-OCH3. |
| Databáze: | OpenAIRE |
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