| L-malate is an important intermediate on the process of metabolism, it plays an important role in generating mitochondria ATP both under aerobic and hypoxic condition. It is easy to be absorbed and come into mitochondrion through cell membrane and promote to produce energy in mitochondrion. The purpose of this investigation is to probe into the different influence malate ingestion on blood lactate and glucose kinetics during aerobic exercise athletes; at the same time, rats were used to study the effect of malate and oligosaccharide solution on the metabolism in muscle and liver.20 male endurance-trained cyclists were divided three groups: contrast group (A), oligosaccharide solution group (G), and malate plus oligosaccharide solution group (M). The nutrient solution is placebo for A group, 500ml-oligosaccharide solution for G group and 3g malate plus oligosaccharide solution for M group. Each subject performed incremental cycling to exhausted to determine the VO2max, 40u1 blood sample were collected at the time of 3, 5, 7, 12, 20, 30min after exercise for analysis blood lactate. Another test was carried out after 2days. Subjects completed 45min cycle ergometer exercise at 60% VO2max. During cycling, 40ul blood sample were collected at the time of 0, 15, 30, and 45min for analysis blood glucose and blood lactate. The results showed that: 1) The athletes supplied with oligosaccharide solution and malate plus oligosaccharide solution performed the cycling to exhausted for a longer time(P<0.05); 2)malate plus oligosaccharide solution have good effect on maintaining a higher blood glucose concentration during exercise, increasing blood lactate removal rate, and decreased the level of serum GOT and GPT after exercise.Twenty-eight rats were randomly divided into 2 groups, the rest group(R) and swimming training group (T). Each group was divided two: one is control(R and T) and another is malate solution (RM and TM). The solution is water for R and T group and malate plus oligosacharide for RM and TM. The swimming group finished swimming with the load of 3-4% weight for an hour. Every group supplied with their nutrient solution 30 min before exercise. The rest control group was killed at rest; other groups were killed immediately after workload swimming. The concentrations of TCAI and ME mRNA in muscle were analysis. The concentrations of malate, 2-oxoglutarate, pyrand HL were determined and AGC and OMC mRNA in liver were studied. At the same time mitochondrail were isolated and prepared for MAPR.Results showed that: 1) Supplement of malate plus oligosaccharide can increase muscles ME mRNA level (P<0.05), but have no effect on TCAI pool and the radio of HL/Pyr in resting rat muscle. 2) Supplement of malate plus oligosaccharide can increase liver OMC mRNA level (P<0.05), reduce the state 4 respirations and increasing P/0 radio in resting rat liver mitochondria (P<0.05). 3) Supplement of malate plus oligosaccharide can inhibit the depletion of muscle and liver glycogen in swimming rats. 4) Supplement of malate plus oligosaccharide have no effect on muscle TCAI and ME mRNA level, but can increase the radio of Pyr/HL in swimming rats (PO.05). 5) Supplement of malate plus oligosaccharide can increase the MA shuttle ability, the concentration of malate and cc-oxoglutarate, the MAPR of liver mitochonrial in swimming rats. All the changes are benefits the increase of hepatic gluconeogenesis.We can conclude that supplement of malate plus oligosaccharide can accelerate the lactate removal after exhausted cycling, keep a higher blood glucose concentration during 45 min cycling. It may be due to the increased abilities of MA shuttle, malate and a-oxoglutarate level and liver mitochonrial ATP production. The elevation in NAD+/NADH as indicated by the elevation of Pyr/HL is the main reason of keeping low lactate production rate during exercise.
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