Goyary, DanswrangSharma, R2005-12-082009-05-272005-12-082009-05-272005-12-08Goyary D, Sharma R. Dietary restriction and triiodothyronine (T3) regulation of malate-aspartate shuttle enzymes in the liver and kidney of mice. Indian Journal of Biochemistry & Biophysics. 2005 Dec; 42(6): 345-9http://imsear.searo.who.int/handle/123456789/27399The activities of malate-aspartate shuttle enzymes viz., cytosolic and mitochondrial aspartate aminotransferase (c- and m-AsAT) and malate dehydrogenase (c- and m-MDH) were measured in liver and kidney of ad libitum (AL) and dietary-restricted (DR) mice and also on triiodothyronine (T3) treatment. The results show that the activity (U/mg protein) of c-AsAT is increased significantly in liver and the activities of c-MDH and m-AsAT are increased significantly in kidney during DR. On T3 treatment, the activities of both the isoenzymes (c- and m-) of MDH and AsAT are increased significantly in the liver of AL- and DR-fed mice. In the kidney, m-MDH showed no effect by T3 treatment, however, c-MDH increased significantly in both AL- and DR-fed mice. In contrast, m-AsAT is increased significantly in the kidney in AL-fed mice, but was not affected in DR-fed animals. In vitro reconstitution of malate-aspartate shuttle showed a higher activity in the liver and kidney of DR-fed mice, as compared to AL-fed ones and also in the T3-treated mice, compared to untreated ones. These findings suggest that malate-aspartate shuttle enzymes are differentially regulated during DR in mice, in order to adapt to the metabolic need of liver and kidney. T3 potentially regulates the shuttle enzymes, albeit to a varying degree in the liver and kidney of AL- and DR-fed mice.engAnimalsAspartate Aminotransferases --metabolismAspartic Acid --metabolismCaloric RestrictionCytosol --drug effectsDietIsoenzymes --metabolismKidney --drug effectsLiver --drug effectsMalate Dehydrogenase --metabolismMalates --metabolismMaleMiceMice, Inbred BALB CMitochondria, Liver --drug effectsTriiodothyronine --pharmacologyJournal Article