Ht. Khor et Dy. Chieng, EFFECT OF DIETARY SUPPLEMENTATION OF TOCOTRIENOLS AND TOCOPHEROLS ON SERUM-LIPIDS IN THE HAMSTER, Nutrition research, 16(8), 1996, pp. 1393-1401
Male Syrian Golden hamsters were fed on semi-synthetic diets containin
g palm olein triglycerides (POTG) as the source of dietary lipid. The
POTG isolated from commercial palm olein were supplemented with 72 ppm
of tocopherols (T) or 162 or 1000 ppm of tocotrienols (T3) isolated f
rom palm fatty acid distillate for 45 days. The animals grew well and
healthy. There were no significant difference in body weight gains. At
the end of the experiments, the hamsters were fasted overnight and bl
ood was taken by cardiac puncture. Serum was prepared by centrifugatio
n at room temperature. Blood lipids were assayed by Sigma enzyme kits
and serum vitamin E levels were analyzed by normal phase HPLC with a f
luorescent detector. Our results show that supplementation of POTG wit
h 72 ppm of tocopherols (POTG-T) raised the serum TC, LDL-C, HDL-C lev
els and lowered the serum TG level as compared to that of the POTG but
the differences were not statistically significant. Supplementation o
f POTG with 162 ppm of tocotrienols (POTG-T3L) lowered the serum TC le
vel significantly (P<0.05), but it did not significantly lower the LDL
-C, HDL-C and serum TG levels as compared with the POTG group. Supplem
entation of POTG with higher amounts of tocotrienols i.e. 1000 ppm did
not result in further reduction in serum TC, LDL-C, HDL-C and TG leve
ls as compared to the POTG-T3L group; on the contrary, the POTG-T3H gr
oup raised LDL-C level significantly when compared to the POTG-T3L gro
up. Analysis of the serum and liver vitamin E levels show that alpha-T
was the main vitamin E in the serum and liver irrespective of whether
tocopherols or tocotrienols were supplemented to the oils. Small amou
nts of tocotrienols appeared in the serum and liver only when tocotrie
nols were supplemented at high level, 1000 ppm. These results indicate
that tocotrienols possess hypo-cholesterolemic effect and tocopherols
may have slight hypercholesterolemic effect in the hamster. Supplemen
tation with high level of tocotrienols did not increase the hypocholes
terolemic effect of the tocotrienols.