Influence of Twinline, an Elemental Diet, on the Generation of Nitric Oxide and Reactive-oxygen Intermediates from Mouse Peritoneal Macrophages and Polymorphonuclear Leukocytes

Abstract

Abstract The influence of Twinline (SNN-6010), an elemental diet containing medium-chain triglycerides, on the generation of nitric oxide (NO) and superoxide (O2−) has been examined in mouse peritoneal macrophages and polymorphonuclear leukocytes (PMN). When PMN and peritoneal macrophages obtained from untreated mice were cultured in medium containing 0·1% and 1% (v/v) Twinline for 48h and stimulated with phorbol myristate acetate or N-formyl-methionyl-leucyl-phenylalanine, their chemiluminescence and O2− generation were strongly suppressed, as was NO generation from peritoneal macrophages. PMN and peritoneal macrophages obtained from mice fed Twinline for 30 days generated much smaller amounts of O2− and NO compared with PMN and peritoneal macrophages from control mice. In conjunction with this suppressed NO generation, inducible NO synthase and its mRNA expression in peritoneal macrophages were suppressed by Twinline both in-vivo and ex-vivo. Although phagocytosis of PMN and peritoneal macrophages was not suppressed by Twinline; their candida-killing activity was markedly suppressed. These results indicate that Twinline suppresses the host-defence function of PMN and peritoneal macrophages by down-regulating their generation of reactive-oxygen intermediates and NO.