| 摘要: | The purpose of this study was to investigate the effect of high
dose β-carotene, canthaxanthin vitamin E on the activities of
antioxidant enzymes and lipid metabolism in rats fed high fat and
cholesterol diet. Experiment I: Seventy-two male Wistar rats ( weight
about 252 g each ) were randomly divided into six group : two control
groups with or without adding 1 % cholesterol and 0.1 % cholic acid ,
the other groups fed 0.2 % β-carotene, beadlet β-carotene,
canthaxanthin or vitamin E with 1 % cholesterol and 0.1 % cholic acid,
all groups contained 15 % soybean oil. The rats of each group were
sacrificed at the end of six-week feeding period, then the artery blood,
liver and feces were collected. The levels of β-carotene, canthaxanthin,
retinol andα-tocopherol were analyzed by HPLC. Analytical items included
the activities of catalase, superoxide dismutase ( SOD ), glutathione
peroxidase ( GSH Px ), glutathione reductase ( GSH Rd ), Glucose-6-
phosphate dehydrogenase ( G-6-PD ), plasma and liver total cholesterol
( TC ), triglyceride ( TG ), thiobarbituric acid reactive substance
( TBARS ) test and liver conjugated diene. Experiment II: Eighty-four
male Wistar rats ( weight about 250 g each ) were randomly divided into
six groups. Experimental design was the same as experiment I. Analytical
items included pathological histology of liver tissue, plasma and liver
total cholesterol ( TC ) and triglyceride ( TG ), plasma cholesterol and
triglyceride level of very low density lipoprotein ( VLDL ), low density
lipoprotein ( LDL ), high density lipoprotein ( HDL ), feces neutral
steroids and total bile acids.
In experiment I, the result showed that plasma β-carotene
concentrations were higher in rats fed beadlet β-carotene, indicating
that beadlet β-carotene had higher absorption than normal β-carotene.
Rats fed cholesterol resulted in low plasma and liver retinol had lower
concentrations, whereas β-carotene feeding resulted in higher plasma and
liver retinol concentrations than the other groups fed cholesterol diets.
The activities of SOD and GSH Px were decreased by feeding cholesterol
diet,while β-carotene, canthaxanthin and vitamin E could increase those
enzyme activities ( P<0.05 ). The cholesterol diets would increase liver
TBARS, conjugated diene, plasma TBARS, and these items were decreased by
feeding antioxidants. Experiment II : Rats fed cholesterol diets groups
were induced series fatty liver, and rats fed β-carotene diets were
better cross to normal. Rats had cholesterol-feeding group had higher
plasma total cholesterol and LDL-C concentrations. Fed β-carotene diets
result in plasma total cholesterol and LDL-C decreased significantly
( P<0.05 ). Canthaxanthin and vitamin E fed groups had higher triglyceride
in liver. The feces neutral steroids and bile acids were increased in rats
fed β-carotene.
In conclusion, β-carotene, Canthaxanthin and vitamin E could decrease
the oxidative stress from dietary cholesterol. The activities of SOD and
GSH Px were decreased in rats fed cholesterol diet and β-carotene,
canthaxanthin and vitamin E could increase those activities. β-carotene-
fed decreased plasma total cholesterol and LDL-C. And β-carotene increased
the feces neutral steroids and total bile acids. |
