The combined effects of garlic oil and fish oil on the hepatic antioxidant and drug-metabolizing enzymes of rats

Abstract

This present study was designed to investigate the combined modulatory effect of garlic oil (GO) and fish oil (FO) on the antioxidant and drug metabolism systems. Rats were fed either a low-maize oil (MO) diet (50 g MO/kg), high-MO diet (235 g MO/kg) or high-FO diet (205 g FO þ 30 g MO/kg) and received different doses of GO (0 -200 mg/kg body weight) three times per week for 6 weeks. Fatty acid analysis showed that 20 : 5n-3 and 22 : 6n-3 were incorporated into serum lipid at the expense of 18 : 2n-6 and 20 : 4n-6 in rats fed the high-FO diet. GO dose-dependently increased hepatic glutathione S-transferase (GST), glutathione reductase, superoxide dismutase (SOD) and ethoxyresorufin O-deethylase (EROD) activities, but decreased glutathione peroxidase and N-nitrosodimethylamine demethylase (NDMAD) activities (P, 0·05). With the exception of glutathione peroxidase, the activities of glutathione reductase, SOD, GST, EROD and NDMAD were modulated by the dietary fat. The high-FO group had greater SOD and EROD activity than either MO-fed group; it also had greater NDMAD activity than the low-MO group (P,0·05). GST activity was higher in rats fed high-FO or high-MO diets than rats fed the low-MO diet. Change in erythromycin demethylase activity, however, was not caused by either dietary fat or GO. Immunoblot assay showed that GO dose-dependently enhanced the protein level of the Ya, Yb1, Yc isoenzymes of GST and cytochrome P450 (CYP) 1A1 and 3A1, but GO suppressed CYP2E1 expression. Regardless of the dosage of GO, the high-FO diet increased CYP1A1, CYP3A1 and CYP2E1 levels compared with the high-and low-MO diets. Accompanying the changes observed in immunoblots, CYP1A1 and CYP3A1 mRNA levels were increased by GO in a dose-dependent manner and also increased additively in combination with FO feeding. These present results indicate that co-administration of GO and FO modulates the antioxidant and drug-metabolizing capacity of animals and that the effect of GO and FO on drug-metabolizing enzymes is additive.

Protictive effects of green tea and garlic on the morphological and oxidative stress changes of hippocampus in aged male and female albino rats

“…These results are in agreement with many studies [44,45] who found that dietary supplement of garlic extract activated the antioxidant system and decreased peroxidation in aortic tissue in their experimental model. The water-soluble organo-sulfur compounds of garlic including S-allyl cysteine, S-allylmercaptocyteine, allicin, and selenium exhibited potent antioxidant and free radical scavenging activities in vitro and in vivo [46,47].…”

Aged black garlic extract induces inhibition of gastric cancer cell growth in�vitro and in�vivo

“…It has been reported that SAC and SAMC possess high radical scavenging activity, which directly removes ROS (33,34). In addition to this direct effect, ABGE also increases the activity of antioxidant enzymes, so that excessive ROS is indirectly cleared (35). Consistent with our study, enhancement of the circulating levels of SOD and GSH-Px were observed following administration of garlic extract in the circulation of tumor-bearing animals.…”

Effects of docosahexaenoic acid supplementation on blood lipids, estrogen metabolism, and in vivo oxidative stress in postmenopausal vegetarian women

“…Fish oil influenced the activity of hepatic CYP450 (Valdes et al, 1995;Chen et al, 2003), which might consequently influence the metabolism of estrogen. The lower status of n-3 long-chain fatty acids in vegetarians seems to be a good model to investigate the influence of DHA supplementation on estrogen metabolism.…”

“…The oxidative metabolism of estrogen is catalyzed predominantly by hepatic cytochrome P450 (CYP450) (Huang et al, 1998;Yamazaki et al, 1998). Dietary fish oil increased the concentration of hepatic overall CYP450 and some subtypes of CYP450 in rats (Valdes et al, 1995;Chen et al, 2003). A preliminary study of Osborne et al (1998) indicated a decreased extent of 16a-hydroxylation of estradiol in women after supplemented with n-3 fatty acids.…”