Age-related effects of chronic ethanol intake on vitamin A status in Fisher 344 rats.
The present study was designed to investigate the interaction of age and ethanol on vitamin A status in rats. Rats aged 2 and 19 mo were fed a liquid diet containing 36% of total energy as ethanol or pair-fed a diet containing isoenergetic carbohydrate in place of ethanol. After 3 wk older rats had lower serum retinol (P = 0.04) and higher vitamin A concentrations in liver (P = 0.0001), esophagus (P = 0.0001) and the proximal (P = 0.03) and distal (P = 0.0001) colon than younger animals. Hepatic microsomal cytochrome P-450, retinyl ester hydrolase (REH) and cellular retinol-binding protein (cRBP) were significantly reduced; acyl coenzyme A: retinol acyltransferase (ARAT) was increased; and alcohol (retinol) dehydrogenase (ADH) activity was unchanged with age. Ethanol ingestion increased serum retinol as well as esophageal and colonic vitamin A levels in both age groups. Hepatic cRBP decreased further in the older rats with ethanol feeding, but no change was noted in the percentage of hepatic vitamin A as retinol or retinyl esters. Ethanol ingestion decreased REH (P = 0.0001) and ARAT activities (P = 0.02) and increased cytochrome P-450 (P = 0.04) but had no effect on the activity of ADH in either age group. These data indicate that, regardless of age, chronic ethanol ingestion significantly alters the tissue distribution of vitamin A; however, ethanol reduced cRBP levels only in older rats.
Mobarhan
S
S
Department of Medicine, School of Public Health, University of Illinois, Chicago 60612.
Seitz
H K
HK
Russell
R M
RM
Mehta
R
R
Hupert
J
J
Friedman
H
H
Layden
T J
TJ
Meydani
M
M
Langenberg
P
P
D000217:Acyltransferases / Q000378:metabolism; D000375:Aging / Q000378:metabolism*; D000426:Alcohol Dehydrogenase / Q000378:metabolism; D000437:Alcoholism / Q000378:metabolism*; D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D003106:Colon / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D015999:Multivariate Analysis; D051381:Rats; D011916:Rats, Inbred F344; D051142:Retinol O-Fatty-Acyltransferase; D012177:Retinol-Binding Proteins / Q000378:metabolism; D054840:Retinol-Binding Proteins, Cellular; D014801:Vitamin A / Q000097:blood / Q000378:metabolism*
D012177:Retinol-Binding Proteins; D054840:Retinol-Binding Proteins, Cellular; D014801:Vitamin A; D003577:Cytochrome P-450 Enzyme System; D000426:Alcohol Dehydrogenase; D000217:Acyltransferases; D051142:Retinol O-Fatty-Acyltransferase; D002265:Carboxylic Ester Hydrolases; C022523:retinyl esterase