Feeding EPA and DHA in both rodent and human studies
resulted in a marked increase in n–3 LC-PUFAs in tissues at the
expense of n–6 FAs (64). Similar to previous studies (60), we also
observed that dietary DHA, more than EPA, lowered hepatic AA
content, which may be partly due to the downregulation of
Fads1 expression observed, which is involved in AA synthesis
from LA. Because elongases are also essential in the biosynthesis
of LC-PUFAs, we analyzed the effect of CO and FO on the
hepatic expression of Elovl2 and Elovl5, and no impact of
treatment on their expression was evident. Previously, feeding
FO had no effect on Elovl2 mRNA abundance, but a down-regulation on Elovl5 mRNA levels has been observed (65, 66).