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Short-chain fatty acid (SCFA) uptake into Caco-2 cells by a pH-dependent and carrier mediated transport mechanism 总被引:4,自引:0,他引:4
Summary The short-chain fatty acids, acetate, propionate, and butyrate, are the most abundant organic anions in the human colon.
SCFA play a pivotal role in maintaining homeostasis in the colon. Particularly butyrate induces cell differentiation and regulates
growth and proliferation of colonic mucosal epithelial cells, whereas it reduces the growth rate of colorectal cancer cell.
Previous studies by several groups, including our own, using isolated membrane vesicles have demonstrated that the uptake
of butyrate is at least in part mediated by a non-electrogenic SCFA−/HCO3
− antiporter. The purpose of the present study was to determine (1) whether Caco-2 cells could serve as an experimental model
to assess the mechanisms of SCFA transport, and (2) whether monocarboxylate transporters could play a role in SCFA transport
in these cells. Caco-2 cells were found to transport 14C-butyrate in a concentration and time dependent manner. The uptake was sodium independent, but was stimulated by lowering
extracellular pH. The uptake of 500μM butyrate was reduced by 49.6% ± 3.3% in the presence of propionate and by 57.2% ± 4.8%
in the presence of 10 mM L-lactate. The addition of 1 mM α-cyano-4-hydroxycinnamate and phloretin, both known to be potent
inhibitors of MCT1, decreased the uptake of 500 μM 14C-butyrate by 59.4% ± 4.1% and 48.9% ± 3.3%, respectively, whereas similar concentrations of DIDS did not have any effect.
These data suggest that the uptake of butyrate in Caco-2 cells occurs via a carrier mediated transport system specific for
monocarboxylic acids, which is in accordance with characteristics of the MCT1.
Received: 28 February 2000, Accepted: 4 May 2000 相似文献