PT - JOURNAL ARTICLE AU - Thompson, L AU - Cockayne, A AU - Spiller, R C TI - Inhibitory effect of polyunsaturated fatty acids on the growth of Helicobacter pylori: a possible explanation of the effect of diet on peptic ulceration. AID - 10.1136/gut.35.11.1557 DP - 1994 Nov 01 TA - Gut PG - 1557--1561 VI - 35 IP - 11 4099 - http://gut.bmj.com/content/35/11/1557.short 4100 - http://gut.bmj.com/content/35/11/1557.full SO - Gut1994 Nov 01; 35 AB - Diets high in polyunsaturated fatty acids may protect against duodenal ulcer, possibly through inhibiting the growth of Helicobacter pylori. This hypothesis was tested in vitro by incubating H pylori microaerophilically with a range of polyunsaturated fatty acids. omega-3 Linolenic acid significantly, but reversibly, inhibited growth at 1.8, 2.5, and 5 x 10(-4) M (p < 0.01), while concentrations of 10(-3) M killed virtually all organisms, with cell lysis observed by electron microscopy. Similar inhibitory effects were seen with other polyunsaturated fatty acids, at concentrations of 2.5 x 10(-4) M the relative inhibitory potencies were oleic (C18:1) < linoleic (C18:2) < arachidonic (C20:4) < omega-3 linolenic (C18:3) = omega-6 linolenic (C18:3) = eicosapentanoic (C20:5) acid. Cell fractionation studies with 14C labelled linolenic acid showed that the linolenic acid was associated with the membrane fraction. Commonly ingested dietary polyunsaturated fatty acids inhibit the growth of H pylori in vitro, an effect which deserves further in vivo study.