Liver choline dehydrogenase and kidney betaine-homocysteine methyltransferase expression are not affected by methionine or choline intake in growing rats.

Article Details

Citation

Slow S, Garrow TA

Liver choline dehydrogenase and kidney betaine-homocysteine methyltransferase expression are not affected by methionine or choline intake in growing rats.

J Nutr. 2006 Sep;136(9):2279-83.

PubMed ID
16920841 [ View in PubMed
]
Abstract

Choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT) are 2 enzymes involved in choline oxidation. BHMT is expressed at high levels in rat liver and its expression is regulated by dietary Met and choline. BHMT is also found in rat kidney, albeit in substantially lower amounts, but it is not known whether kidney BHMT expression is regulated by dietary Met or choline. Similarly, CHDH activity is highest in the liver and kidney, but the regulation of its expression by diet has not been thoroughly investigated. Sprague Dawley rats ( approximately 50 g) were fed, for 9 d in 2 x 3 factorial design (n = 8), an l-amino acid-defined diet varying in l-Met (0.125, 0.3, or 0.8%) and choline (0 or 25 mmol/kg diet). Liver and kidney BHMT and CHDH were assessed using enzymatic, Western blot, and real-time PCR analyses. Liver samples were also fixed for histological analysis. Liver BHMT activity was 1.3-fold higher in rats fed the Met deficient diet containing choline, which was reflected in corresponding increases in mRNA content and immunodetectable protein. Independent of dietary choline, supplemental Met increased hepatic BHMT activity approximately 30%. Kidney BHMT and liver CHDH expression were refractory to these diets. Some degree of fatty liver developed in all rats fed a choline-devoid diet, indicating that supplemental Met cannot completely compensate for the lack of dietary choline in growing rats.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
MethionineBetaine--homocysteine S-methyltransferase 1ProteinHumans
Unknown
Product of
Details
Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
CholineCholine dehydrogenase, mitochondrialProteinHumans
Unknown
Substrate
Details
Choline salicylateCholine dehydrogenase, mitochondrialProteinHumans
Unknown
Substrate
Details