Enteral nutrition with stearidonic acid increases incorporation of antiinflammatory N-3 fatty acids in liver phospholipids in the rat

• Published in: The Journal of surgical research 2004-10, Vol.121 (2), p.330-331
• Main Authors: Phipps, J.E., Enderson, B.L., Jones, L., Whelan, J., Karlstad, M.D.
• Format: Article
• Language: English
• ISSN: 0022-4804; 1095-8673
• DOI: 10.1016/j.jss.2004.07.206

We have shown that an enteral nutrition formula containing eicosa-pentaenoic acid (20:5n-3; EPA) provided beneficial antiinflammatory effects in critically ill patients with acute lung injury. The use of diets enriched with stearidonic acid (18:4n-3; SDA) may provide a novel means to increase EPA content in tissue phospholipids and to provide the health benefits typically associated with n-3 fatty acids from fish oil. There is little known about the effects of increased consumption of SDA on tissue phospholipid fatty acid composition. We examined whether diets supplemented with SDA can be used as a precursor to increase EPA content in liver phospholipids and to determine the effectiveness of SDA in increasing tissue EPA content as compared with dietary EPA in rats. Male Long--Evans rats ( n = 10) were randomly divided into three dietary groups and fed a modified US-17 diet providing 200 kcal/kg/day and containing either 2% oleic acid (OA, 18:1 n-9) ( n = 4), 1% EPA /1% OA ( n = 3), or 1% SDA/1% OA ( n = 3) for 2 weeks. Dietary fatty acid composition was controlled by substituting the ethyl esters of EPA and SDA for OA; thus changes in phospholipid fatty acid composition would be the result of dietary changes of these fatty acids. The fatty acid compositions (mol %) of liver phospholipids were determined by gas chromatography. There was a small reduction, although not significant, in AA content with EPA and SDA as compared with OA. SDA resulted in an increase in EPA content in liver phospholipids that was approximately 50% of that for EPA. There was a smaller increase in tissue DPA content with SDA than EPA as compared with OA. There was no significant increase in DHA content with either EPA or SDA as compared with OA. These results indicate that dietary SDA can be used to increase EPA content in liver phospholipids and the relative effectiveness of SDA conversion to EPA and incorporation into tissue phospholipids was equivalent to one-half of dietary EPA. TABLE—ABSTRACT P77 Fatty acid OA EPA SDA 20:4 n-6 (AA) 28.3 ± 1.02 a 25.1 ± 0.42 a 26.6 ± 0.30 a 20:5 n-3 (EPA) 0.02 ± 0.06 a 1.21 ± 0.43 b 0.66 ± 0.04 a,b 22:5 n-3 (DPA) 0.16 ± 0.04 a 1.65 ± 0.33 b 1.01 ± 0.04 c 22:6 n-3 (DHA) 6.49 ± 0.26 a 6.39 ± 0.004 a 6.67 ± 0.43 a Note. Values with different superscripts are significantly different ( P ≤ 0.05).