DIETS RICH IN EICOSAPENTAENOIC ACID AND GAMMA-LINOLENIC ACID AFFECT PHOSPHOLIPID FATTY-ACID COMPOSITION AND PRODUCTION OF PROSTAGLANDINS E(1), E(2) AND E(3) IN TURBOT (SCOPHTHALMUS-MAXIMUS), A SPECIES DEFICIENT IN DELTA-5 FATTY-ACID DESATURASE
Jg. Bell et al., DIETS RICH IN EICOSAPENTAENOIC ACID AND GAMMA-LINOLENIC ACID AFFECT PHOSPHOLIPID FATTY-ACID COMPOSITION AND PRODUCTION OF PROSTAGLANDINS E(1), E(2) AND E(3) IN TURBOT (SCOPHTHALMUS-MAXIMUS), A SPECIES DEFICIENT IN DELTA-5 FATTY-ACID DESATURASE, Prostaglandins, leukotrienes and essential fatty acids, 53(4), 1995, pp. 279-286
Duplicate groups of juvenile turbot, (Scophthalmus maximus), were fed
diets containing either Marinol K (MO), a marine fish oil rich in eico
sapentaenoic acid (EPA; 20:5, n-3) or borage oil (BO), rich in gamma-l
inolenic acid (GLA; 18:3, n-6), for a period of 12 weeks. Individual p
hospholipid fatty acid compositions from hearts of fish fed BO had sig
nificantly more 18:2, n-6, GLA, 20:2, n-6, dihomo-gamma-linolenic acid
(DHGLA; 20:3, n-6) and total n-6 polyunsaturated fatty acids (PUFA),
but significantly less arachidonic acid (AA; 20:3, n-6), compared to f
ish fed MO. In both phosphatidylcholine (PC) and phosphatidylethanolam
ine (PE) from heart, the DHGLA was increased by over 50-fold in fish f
ed BO while AA was reduced by over two-thirds, compared to fish fed MO
. In brain, EPA was the major C-20 PUFA, i.e. potential eicosanoid pre
cursor in all phospholipids from fish fed MO, with the EPA level being
twice that of AA in brain phosphatidylinositol (PI). DHGLA was the ma
jor C-20 PUFA in all phospholipid classes from fish fed BO. In kidney
and gill, EPA was the predominant C-20 PUFA in all phospholipid classe
s, except PI, in fish fed MO. In kidney of fish fed BO, DHGLA was the
major C-20 PUFA in all phospholipid classes, except PE. In gill of fis
h fed BO, DHGLA was the major C-20 PUFA in all phospholipid classes, i
ncluding PI, where DHGLA was over 2.5-fold greater than AA. In homogen
ates of heart, kidney and gill from BO-fed fish the prostaglandin E(1)
(PGE(1)) concentration was significantly increased compared to MO-fed
fish. In heart and kidney homogenates from fish fed MO the PGE(3) con
centration was significantly increased compared to fish fed BO. The ra
tio of PGE(2)/PGE(1) was significantly reduced in brain, heart, kidney
and gill homogenates from fish fed BO compared to those fed MO.