Vitamin B₆ Deficiency can Reduce Fuel Storage and Utilization in Physically Trained Rats

This study investigated the effect of vitamin B₆ deficiency on the utilization and recuperation of stored fuel in physically trained rats. 48 rats were given either vitamin B₆-deficient (B₆–) diet or control (B₆+) diet for 4 weeks and were trained on treadmill for 30 minutes daily. All animals were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed. Animals in the AE group were allowed to take a rest for 2 hours after being exercised like the DE group. Glucose and free fatty acids were compared in plasma. Glycogen and triglyceride were compared in liver and skeletal muscle. Protein levels were compared in plasma, liver, and skeletal muscle. Compared with the B₆+ group, plasma glucose levels of the B₆– group were significantly lower before and after exercise. Muscle glycogen levels of the B₆– group were significantly lower than those of the B₆+ group regardless of exercise. The liver glycogen level of the B₆– group was also significantly lower than that of B₆+ group during and after exercise. Before exercise, plasma free fatty acid levels were not significantly different between the B₆+ and B₆– groups, and plasma free fatty acid levels of the B₆– group were significantly lower during and after exercise. The muscle triglyceride level of the B₆– group was significantly lower than that of the B₆+ group before exercise, and there were no differences between B₆+ and B₆– groups during and after exercise. Liver triglyceride levels were not significantly different between B₆+ and B₆– groups. Plasma protein levels of the B₆– group were lower than those of B₆+ before and after exercise. Muscle protein levels of the B₆– group were not significantly different from those of the B₆+ group. Liver protein levels of the B₆– group were significantly lower than that of the B₆+ group after exercise. Liver protein levels of both B₆+ and B₆– groups were not significantly changed, regardless of exercise. Thus, it is suggested that vitamin B₆ deficiency may reduce fuel storage and utilization with exercise in physically trained rats.