Fat transforms ascorbic acid from inhibiting to promoting acid-catalysed N-nitrosation

• DOI: 10.1136/gut.2007.128587
• Publication Date: 2007-09-05T00:24:45Z
• Authors: E Combet; S Paterson; K Iijima; J Winter; W Mullen; A Crozier; T Preston; K E L McColl
• Keywords: Nitrosation; Nitrosamine

<h3>Background:</h3> The major potential site of acid nitrosation is the proximal stomach, an anatomical prone to a rising incidence metaplasia and adenocarcinoma. Nitrite, pre-carcinogen present in saliva, can be converted nitrosating species <i>N-</i>nitroso compounds by acidification at low gastric pH presence thiocyanate. <h3>Aims:</h3> To assess effect lipid ascorbic on nitrosative chemistry under conditions simulating human stomach. <h3>Methods:</h3> was modelled <i>in vitro</i> measuring four secondary amines <i>N-</i>nitrosamines formed were measured gas chromatography–ion-trap tandem mass spectrometry, while nitric oxide oxygen levels amperometrically. <h3>Results:</h3> In absence lipid, stress inhibited through conversion oxide. Addition reduced amount <i>N-</i>nitrosodimethylamine fivefold, <i>N-</i>nitrosomorpholine &gt;1000-fold, totally prevented formation <i>N-</i>nitrosodiethylamine <i>N-</i>nitrosopiperidine. contrast, when 10% present, increased <i>N-</i>nitrosodimethylamine, <i>N-</i>nitrosopiperidine approximately 8-, 60- 140-fold, respectively, compared with acid. <h3>Conclusion:</h3> converts from inhibiting promoting nitrosation. This may explained oxide, aqueous phase, being able regenerate reacting phase.