Effects of L-malate on physical stamina and activities of enzymes related to the malate-aspartate shuttle in liver of mice.
L-malate, a tricarboxylic acid cycle (TCA) intermediate, plays an important role in transporting NADH from cytosol to mitochondria for energy production and may be involved in the beneficial effects of improving physical stamina. In the present study, we investigated the effects of L-malate on the performance of forced swimming time and blood biochemical parameters related to fatigue - blood urea nitrogen (BUN), glucose (Glc), creatine kinase (CK),total protein (TP) and lactic acid (LA). To investigate the effects of L-malate on the malate-aspartate shuttle and energy metabolism in mice, the activities of enzymes related to the malate-aspartate shuttle were measured. L-malate was orally administered to mice continuously for 30 days using a feeding atraumatic needle. The swimming time was increased by 26.1 % and 28.5 %, respectively, in the 0.210 g/kg and 0.630 g/kg L-malate-treated group compared with the control group. There were no differences in the concentrations of Glc, BUN and TP between the L-malate-treated groups and the control groups. However, the levels of CK were significantly decreased in the L-malate-treated groups. The results predict a potential benefit of L-malate for improving physical stamina and minimizing muscle damage during swimming exercise. The activities of cytosolic and mitochondrial malate dehydrogenase were significantly elevated in the L-malate-treated group compared with the control group. These enzymatic activities may be useful indicators for evaluating changes affecting the malate-aspartate shuttle and energy metabolism in the liver of mice.
Guangdong Institute of Microbiology, Guangzhou, China.
J L
JL
Wu
Q P
QP
Wu
J M
JM
Huang
R
R
Chen
M
M
Cai
J B
JB
Tan
D000284:Administration, Oral; D000818:Animals; D024443:Aspartate Aminotransferase, Cytoplasmic / Q000378:metabolism; D024442:Aspartate Aminotransferase, Mitochondrial / Q000378:metabolism; D001224:Aspartic Acid / Q000378:metabolism*; D001786:Blood Glucose / Q000378:metabolism; D001806:Blood Urea Nitrogen; D002352:Carrier Proteins / Q000378:metabolism*; D002952:Citric Acid Cycle; D003402:Creatine Kinase / Q000097:blood; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D019344:Lactic Acid / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008291:Malate Dehydrogenase / Q000378:metabolism; D008293:Malates / Q000008:administration & dosage / Q000378:metabolism*; D008297:Male; D051379:Mice; D008930:Mitochondria, Liver / Q000378:metabolism; D018763:Muscle Fatigue / Q000187:drug effects; D010807:Physical Endurance / Q000187:drug effects; D013550:Swimming
D001786:Blood Glucose; D002352:Carrier Proteins; D008293:Malates; D001224:Aspartic Acid; D019344:Lactic Acid; C030298:malic acid; D007770:L-Lactate Dehydrogenase; D008291:Malate Dehydrogenase; D024443:Aspartate Aminotransferase, Cytoplasmic; D024442:Aspartate Aminotransferase, Mitochondrial; D003402:Creatine Kinase