Purified dietary n-3 polyunsaturated fatty acids alter diacylglycerol mass and molecular species composition in concanavalin A-stimulated murine splenocytes.
A low-dose, short-term dietary supplementation with highly purified (n-3) fatty acid ethyl esters was studied in mice to determine the effect on splenic cell membrane diacylglycerol mass and composition. Mice were fed diets containing either 3% safflower oil (SAF) ethyl esters, 2% SAF plus 1% eicosapentaenoic acid ethyl ester (EPA), or 2% SAF plus 1% docosahexaenoic acid ethyl ester (DHA). Following a 10-day feeding period, pathogen-free mice were sacrificed and splenic cells isolated and stimulated with concanavalin A (Con A) at 10 micrograms/ml. After 0 min (basal), 5 min, and 180 min, 1,2-diacyl, 1-O-alkyl-2-acyl, and 1-O-alkenyl-2-acyl-sn-glycerol subclasses were isolated and quantitated by HPLC. Diacylglycerol (DAG) was found to be the major diradylglycerol (DG) component in murine splenocytes. DHA-fed mice had significantly (P < 0.05) higher levels of DAG at all stimulation time points relative to EPA and SAF animals. Significant effects (P < 0.05) of diet, time, and a diet x time interaction (P < 0.05) were noted for various DAG molecular species. In general, a significantly higher (n-3) polyunsaturated fatty acid (PUFA) content in the EPA and DHA groups, and a significantly higher (n-6) PUFA content in the SAF group was noted. 18:0-22:5(n-3), 18:1-22:5(n-3) and 16:1-20:5(n-3) species were present only in EPA and DHA-DAG, confirming the incorporation of (n-3) fatty acids into splenocyte DAG. The data indicate that the molecular species composition of murine splenocyte DAG is significantly modulated by low-dose, short-term EPA and DHA feeding. In addition, substitution of SAF with DHA results in an increase in DAG mass. These alterations could potentially influence signal transduction pathways regulating lymphocyte function.
Fowler
K H
KH
Department of Animal Science, Molecular, Texas A&M University, College Station 77843-2471.
McMurray
D N
DN
Fan
Y Y
YY
Aukema
H M
HM
Chapkin
R S
RS
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003208:Concanavalin A / Q000494:pharmacology; D004041:Dietary Fats / Q000302:isolation & purification / Q000494:pharmacology*; D004075:Diglycerides / Q000737:chemistry / Q000378:metabolism*; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D015398:Signal Transduction; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D004041:Dietary Fats; D004075:Diglycerides; D003208:Concanavalin A; D004281:Docosahexaenoic Acids; C035276:eicosapentaenoic acid ethyl ester; C067518:4,7,10,13,16,19-docosahexaenoic acid ethyl ester; D015118:Eicosapentaenoic Acid