Modulation of T-lymphocyte function by dietary n-6 and n-3 fatty acids /
The effect of short-term (1 0 day) dietary supplementation with highly purified n-3 polyunsaturated fatty acid ethyl esters was examined with respect to murine T-lymphocyte proliferation, IL-2 secretion, signal transduction, and gene expression. Mice were fed identical, isocaloric diets containing...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=743267071&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The effect of short-term (1 0 day) dietary supplementation with highly purified n-3 polyunsaturated fatty acid ethyl esters was examined with respect to murine T-lymphocyte proliferation, IL-2 secretion, signal transduction, and gene expression. Mice were fed identical, isocaloric diets containing either 3% safflower oil ethyl esters (SAF), 2% SAF plus 1% arachidonic acid triglyceride form (AA), 2% SAF plus 1% eicosapentaenoic acid ethyl ester (EPA), or 2% SAF plus 1% docosahexaenoic acid ethyl ester (DHA). Generally, the AA fed mice responded like the SAF group, indicating the dietary effects were due to the inclusion of EPA and DHA and not reductions in SAF. Dietary EPA and DHA significantly (P<0.05) suppressed concanavalin A-induced T-lymphocyte interleukin2 (IL-2) secretion and proliferative response compared to the AA and SAF fed groups. Flow cytometric analysis of CD4+ and CD8+ T-lymphocyte subsets demonstrated that dietary lipid did not exert a major influence on these T-lymphocyte subsets in murine spleens. The suppressed EL-2 secretion was preceded temporally by blunted diacylglycerol (DAG) and ceramide kinetics in Con A-activated splenic lymphocyte cultures. Since DAG and ceramide can potentially modulate T-lymphocyte gene expression, the effect of dietary lipid on IL-2 and IL-2 receptor u. chain (IL-2R (x) MRNA expression in response to Con A was determined. Overall, dietary lipid did not influence IL-2 MRNA expression. In contrast, dietary EPA and DHA significantly (P<0.05) suppressed IL-2R (X MRNA levels relative to SAF and AA fed mice. Analysis of protein kinase C (x, Pl and C MRNA expression revealed that dietary EPA and DHA enhanced PKC isoform MRNA levels compared to the SAF and AA groups. Overall, this study demonstrates for the first time that (i) both dietary EPA and DHA suppress fL-2 secretion and impair lymphoproliferation, both of which are preceded temporally by reduced DAG and ceramide mass; and (ii) these n-3 fatty acids selectively modulate IL-2, IL-2R a, and PKC a, PI, and C gene expression in Con A-activated murine splenic lymphocyte cultures. |
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| Item Description: | Vita. "Major Subject: Nutrition". In title, numerals are used. |
| Physical Description: | xi, 144 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |