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.