Back to Search
Start Over
Modulation of rat liver urea cycle and related ammonium metabolism by sex and cafeteria diet
- Source :
- Dipòsit Digital de la UB, Universidad de Barcelona, Recercat. Dipósit de la Recerca de Catalunya, instname
- Publication Year :
- 2016
- Publisher :
- Royal Society of Chemistry, 2016.
-
Abstract
- High-energy (hyperlipidic) cafeteria diets induce insulin resistance limiting glucose oxidation, and lower amino acid catabolism. Despite high amino-N intake, amino acids are preserved, lowering urea excretion. We analysed how energy partition induced by cafeteria diet affects liver ammonium handling and urea cycle. Female and male rats were fed control or cafeteria diets for 30 days. There was a remarkable constancy on enzyme activities and expressions of urea cycle and ammonium metabolism. The key enzymes controlling urea cycle: carbamoyl-P synthase 1, arginino-succinate synthase and arginase expressions were decreased by diet (albeit more markedly in males), and their activities were correlated with the gene expressions. The effects observed, in ammonium handling enzyme activities and expressions behaved in a way similar to that of the urea cycle, showing a generalized downregulation of liver amino acid catabolism. This process was affected by sex. The different strategies of amino-N handling by females and males further modulated the preservation of 2-amino N under sufficient available energy. The effects of sex were more marked than those of diet were, since different metabolism survival strategies changed substrate partition and fate. The data presented suggest a lower than expected N flow to the liver, which overall importance for amino acid metabolism tends to decrease with both cafeteria diet and female sex. Under standard conditions, liver availability of ammonium was low and controlled. The situation was unchanged (or even lowered) in cafeteria-fed rats, ultimately depending on intestinal amino acid catabolism.
- Subjects :
- 0301 basic medicine
medicine.medical_specialty
General Chemical Engineering
Rats as laboratory animals
Cafeteria
03 medical and health sciences
chemistry.chemical_compound
Internal medicine
medicine
Urea
Ammonium
Rates (Animals de laboratori)
chemistry.chemical_classification
biology
Catabolism
General Chemistry
Metabolism
biology.organism_classification
Amino acid
Diet
Arginase
Alimentació
030104 developmental biology
Endocrinology
chemistry
Biochemistry
Urea cycle
Subjects
Details
- Database :
- OpenAIRE
- Journal :
- Dipòsit Digital de la UB, Universidad de Barcelona, Recercat. Dipósit de la Recerca de Catalunya, instname
- Accession number :
- edsair.doi.dedup.....496cdcb7464545db5bec3be89aa1e657