Summary: | <p>Abstract</p> <p>Background</p> <p>Mice that lack acyl CoA:diacylglycerol acyltransferase (<it>Dgat1</it><sup>-/- </sup>mice) are reported to have a reduced body fat content and improved glucose tolerance and insulin sensitivity. Studies so far have focussed on male null mice fed a high fat diet and there are few data on heterozygotes. We compared male and female <it>Dgat1</it><sup>-/-</sup>, <it>Dgat1</it><sup>+/- </sup>and <it>Dgat1</it><sup>+/+ </sup>C57Bl/6 mice fed on either standard chow or a high fat diet.</p> <p>Results</p> <p>Body fat content was lower in the <it>Dgat1</it><sup>-/- </sup>than the <it>Dgat1</it><sup>+/+ </sup>mice in both experiments; lean body mass was higher in male <it>Dgat1</it><sup>-/- </sup>than <it>Dgat1</it><sup>+/+ </sup>mice fed on the high fat diet. Energy intake and expenditure were higher in male <it>Dgat1</it><sup>-/- </sup>than <it>Dgat1</it><sup>+/+ </sup>mice; these differences were less marked or absent in females. The body fat content of female <it>Dgat1</it><sup>+/- </sup>mice was intermediate between that of <it>Dgat1</it><sup>-/- </sup>and <it>Dgat1</it><sup>+/+ </sup>mice, whereas male Dgat1<sup>+/- </sup>mice were similar to or fatter than <it>Dgat1</it><sup>+/+ </sup>mice. Glucose tolerance was improved and plasma insulin reduced in <it>Dgat1</it><sup>-/- </sup>mice fed on the high fat diet, but not on the chow diet. Both male and female <it>Dgat1</it><sup>+/- </sup>mice had similar glucose tolerance to <it>Dgat1</it><sup>+/+ </sup>mice.</p> <p>Conclusion</p> <p>These results suggest that although ablation of DGAT1 improves glucose tolerance by preventing obesity in mice fed on a high fat diet, it does not improve glucose tolerance in mice fed on a low fat diet.</p>
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