Hepatic histidase gene expression responds to protein rehabilitation in undernourished growing rats.
We studied the effect of nutritional rehabilitation with a 6, 18 or 50% casein diet in undernourished rats on histidase (Hal) expression. Undernutrition was induced by feeding rats a 0.5% casein diet for 5 wk. Over this period, growth, serum total proteins and insulin-like growth factor-I (IGF-I) levels were significantly lower than those of rats that freely consumed an 18% casein diet. During this period, undernutrition also significantly reduced Hal activity and Hal-mRNA concentration. Nutritional rehabilitation for 21 d with a 6% casein diet did not change any of these variables. Nutritional rehabilitation with an 18 or 50% casein diet for 1 d initiated the restoration of Hal activity and mRNA concentration. After 10 d of consuming 18 or 50% casein diets, Hal activity was 5- and 14-fold, and mRNA concentration was 8.5- and 23-fold higher, respectively, than in the protein-undernourished group (PU). During this period, body weight, total serum proteins and IGF-I levels were also significantly (P < 0.05) higher than those of the PU group. At the end of 21 d of rehabilitation with an 18 or 50% casein diet, Hal activity was 14- and 31-fold higher and Hal mRNA concentration was 10- and 24-fold higher, respectively, than in the PU group. In conclusion, our data showed that rehabilitation of undernourished rats with a 6% casein diet was not sufficient to re-establish growth indicators, Hal activity or gene expression, and that nutritional rehabilitation with an 18 or 50% casein diet effectively re-established body weight , biochemical variables and the capacity of histidase gene expression to eliminate the excess of protein.
Departamento de Fisiología de la Nutrición, Instituto Nacional de la Nutrición,"Salvador Zubirán" México, D.F. México, 14000, USA.
A R
AR
Tovar
A
A
Santos
A
A
Halhali
H
H
Bourges
N
N
Torres
D000704:Analysis of Variance; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002364:Caseins / Q000008:administration & dosage; D004044:Dietary Proteins / Q000627:therapeutic use*; D015971:Gene Expression Regulation, Enzymologic; D006638:Histidine Ammonia-Lyase / Q000235:genetics* / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009929:Organ Size / Q000187:drug effects; D011502:Protein-Energy Malnutrition / Q000178:diet therapy* / Q000201:enzymology / Q000534:rehabilitation; D051381:Rats; D017208:Rats, Wistar
D001798:Blood Proteins; D002364:Caseins; D004044:Dietary Proteins; D007334:Insulin-Like Growth Factor I; D006638:Histidine Ammonia-Lyase