Galactosamine-Induced Acute Liver Injury in Rats Reduces Hepatic .ALPHA.-Tocopherol Transfer Protein Production

Abstract

SummaryThe liver plays the main role in the secretion of food-derived ␣ -tocopherol into the circulation through the functioning of ␣ -tocopherol transfer protein ( ␣ -TTP). However, the effect of liver disease on ␣ -TTP level and ␣ -tocopherol metabolism has not been clarified. We examined the amount of liver ␣ -TTP and its effect on serum ␣ -tocopherol concentration in liver injury. Male Wistar rats were injected intraperitoneally with D -galactosamine at 800 mg/kg body weight, and liver and serum lipid concentrations, ␣ -tocopherol concentrations, and hepatic ␣ -TTP mRNA and protein levels were measured at 24, 48, and 72 h after injection. On the basis of body weight changes and serum transaminase activities, the livers were found to be in an injured state 24 and 48 h after galactosamine injection but had recovered by 72 h. The hepatic ␣ -TTP mRNA level was reduced throughout the experimental period, and at 48 h after injection the ␣ -TTP protein level had begun to decrease. Lipid and ␣ -tocopherol concentrations in the serum were decreased at 24 and 48 h after injection and increased at 72 h. Liver lipid concentrations were increased at 24 and 48 h after injection, but the liver ␣ -tocopherol concentration was unchanged. These results show that galactosamine-induced liver injury decreases hepatic ␣ -TTP synthesis in rats. Serum ␣ -tocopherol concentration was not directly affected by the acute change in hepatic ␣ -TTP level, suggesting that the chronic changes in ␣ -TTP activity would be necessary to regulate serum ␣ -tocopherol concentration.

Effects of pregnenolone-16α-carbonitrile on vitamin E status and protein levels of antioxidant enzymes in male rats fed a vitamin E-supplemented diet

“…α-TTP mRNA levels are reduced and lipid peroxidation increased in rats exposed to hyperoxia for 48 h. 31 α-TTP mRNA and protein levels are also reduced in a rat hepatocellular carcinoma 32 and galactosamine-induced liver injury. 33 However, in the present study, α-TTP protein levels were not decreased. This suggests that the regulation of α-TTP levels is PXR-independent and not relevant to CYP3A induction.…”

Effect of globin digest on the liver injury and hepatic gene expression profile in galactosamine-induced liver injury in SD rats

“…Although the decrease in hepatic TG in the GD group was not enough to decrease the liver weight, the TBARS content in GalN-injured liver was a decreasing tendency by GD. The effect of GD on the liver weight after long-term administration could not be examined, because GalN-induced liver injury was reversible (Takenaka et al, 2007). GD suppressed the increased GSSG content, and increased the decreased protein, GSH contents, and CAT activity in GalN-injured liver.…”

Dietary Vitamin E Deficiency Increases Anxiety-Like Behavior in Juvenile and Adult Rats

“…The -Tocopherol concentration was determined fluorometrically by HPLC, as described previously. 20) The analytical column used was SHODEX 5SIL (Showa Denko, Tokyo) with a mobile phase of n-hexane/isopropanol (99.5:0.5, v/v), and -tocopherol was detected with excitation at 295 nm and emission at 340 nm.…”