Long-term administration of tocotrienols and tumor-marker enzyme activities during hepatocarcinogenesis in rats.
The effects of long-term administration of tocotrienol on hepatocarcinogenesis in rats induced by diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) were investigated by determining the activities of gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), glutathione S-transferases (GSTs), and glutathione (GSH) levels in blood and liver. Twenty-eight male 7- to 8-wk-old Rattus norwegicus rats, weighing 120-160 g, were used in this study. The rats were divided into four treatment groups: a control group on a basal diet, a group fed a basal diet supplemented with tocotrienol (30 mg/kg food), a group treated with DEN/AAF, and a group treated with DEN/AAF and fed a diet supplemented with tocotrienol (30 mg/kg food). Blood was collected monthly, and GGT, ALP, and GSH levels were determined. The rats were killed after 9 mo, and the livers were examined morphologically. Grayish white nodules (2/liver) were found in all the DEN/AAF-treated rats (n = 10), but only one of the rats treated with DEN/AAF and supplemented with tocotrienol (n = 6) had liver nodules. A significant increase in the level of blood and liver GSH, ALP, and GGT activities was observed in the DEN/AAF-treated rats. Liver GSTs were similarly increased with DEN/AAF treatment. Tocotrienol supplementation attenuated the impact of the carcinogens in the rats.
Rahmat
A
A
Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur.
Ngah
W Z
WZ
Shamaan
N A
NA
Gapor
A
A
Abdul Kadir
K
K
D015073:2-Acetylaminofluorene / Q000037:antagonists & inhibitors; D000469:Alkaline Phosphatase / Q000187:drug effects; D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects* / Q000378:metabolism; D004052:Diethylnitrosamine; D005978:Glutathione / Q000187:drug effects; D005982:Glutathione Transferase / Q000187:drug effects; D008113:Liver Neoplasms / Q000139:chemically induced / Q000201:enzymology* / Q000517:prevention & control*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000494:pharmacology; D005723:gamma-Glutamyltransferase / Q000187:drug effects
D014408:Biomarkers, Tumor; D014810:Vitamin E; D004052:Diethylnitrosamine; D015073:2-Acetylaminofluorene; D005723:gamma-Glutamyltransferase; D005982:Glutathione Transferase; D000469:Alkaline Phosphatase; D005978:Glutathione