History Ethanol consumption might induce hepatic apoptosis and cause liver damage. diet with β-carotene supplementation at 2.6 mg/kg BW/day). After 12 weeks rats were sacrificed and blood and liver samples were collected for analysis. Results Lipid peroxidation and hepatic cytochrome P450 2E1 (CYP2E1) expression had increased and hepatic Fas ligand caspase-8 cytochrome c caspase-9 and -3 expressions had significantly increased in the E group. However lipid peroxidation and CYP2E1 caspase-9 and -3 expressions were significantly lower and Bcl-xL expression was higher in the ELB group. The hepatic tumor necrosis factor (TNF)-α level lipid peroxidation and cytochrome c expression were significantly lower and Bcl-2 expression was significantly higher in the EHB group. Conclusions The results suggest that ethanol treatment causes oxidative stress and hepatic apoptosis leading to liver injury and β-carotene supplementation (0.52 mg/kg BW/day) can prevent ethanol-induced liver damage by decreasing ethanol-induced oxidative stress and inhibiting apoptosis in the liver. (12). However excess β-carotene supplementation (30-45 mg/1 0 kcal diet) might aggravate ethanol-induced liver damage (13). Therefore β-carotene should be administered cautiously in an animal experimental model of ALD. In our previous study we found NPS-2143 that β-carotene supplementation prevented ethanol-induced liver damage and increased the reduced glutathione (GSH) concentration in rats (14). In addition 1 μM β-carotene exhibited antioxidant and antiapoptotic properties and prevented ethanol-induced cytotoxicity in primary hepatocytes (15). However the use of β-carotene supplementation in ALD studies should be carefully considered as it is still unknown whether high-dose β-carotene supplementation is harmful. Using that information as a basis the objective of the present study was to investigate the effects of different doses of β-carotene supplementation on the antioxidant capacity and hepatic apoptosis in rats chronically fed ethanol. Materials and methods Animals and diets Six-week-old male Wistar (BioLASCO Taiwan Taipei Taiwan) rats were used in this study. Rats were housed in an air-conditioned room at 23±2 °C with 50-70% humidity and a 12-h light-dark routine. After a week of acclimation rats had been split into six organizations (n=10) relating to identical plasma aspartate transaminase (AST) and alanine transaminase (ALT) actions. The six organizations had been the following: C (control liquid NPS-2143 diet plan) CLB [control liquid diet plan with β-carotene supplementation NPS-2143 at 0.52 mg/kg bodyweight NPS-2143 (BW)/day time] CHB (control water diet plan with β-carotene supplementation at 2.6 mg/kg BW/day time) E (ethanol water diet plan) ELB (ethanol water diet plan with β-carotene supplementation NPS-2143 at 0.52 mg/kg BW/day time) and EHB (ethanol water diet plan with β-carotene supplementation at 2.6 mg/kg BW/day time). The low dosage of β-carotene supplementation (0.52 UVO mg/kg BW/day time) was chosen according to your previous research (14). The liquid diet programs had been prepared newly daily and customized from Lieber and DeCarli (16). The ethanol liquid diet plan offered 18.23% of total calories as protein 21.70% as fat 25.07% as carbohydrates and 35% as ethanol. The control liquid diet plan offered an isocaloric diet plan where the ethanol was changed with corn starch. β-Carotene was presented with as Solatene? (10% β-carotene in beadlets Hoffmann-La Roche South SAN FRANCISCO BAY AREA CA USA). All methods had been authorized by the Institutional Pet Treatment NPS-2143 and Use Committee of Taipei Medical University. Sample preparation Rats were anesthetized and sacrificed after feeding them the respective diets for 12 weeks. Blood samples were collected in heparin-containing tubes and were centrifuged to separate the plasma (1 200 for 15 min at 4 °C). All plasma samples were stored at -80 °C until being assayed. Liver tissues were rapidly excised and stored at -80 °C for further analysis. One gram of liver tissue was homogenized in 4 mL buffer (0.25 mM sucrose 10 mM Tris-HCl and 0.25 mM phenylmethylsulfonyl fluoride; pH 7.4). The homogenate was then centrifuged at 10 0 for 15 min at 4 °C. The supernatant was analyzed for the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio and lipid peroxide levels. Measurements of plasma AST and ALT activities To investigate the liver function during the experimental period plasma AST and ALT activities were measured with a Beckman Synchron LXTM system (Beckmen Coulter Brea CA USA) at 340.