Elevated plasma glucagon in amyotrophic lateral sclerosis

This study shows an abnormality in glucagon levels that may explain the glucose intolerance, abnormal insulin reactions, and abnormal plasma amino acid levels seen in amyotrophic lateral sclerosis (ALS). We randomly administered two test meals, differing only in protein source (soy versus casein) at least 1 week apart and measured fasting and postprandial bloods for glucagon, insulin, and glucose levels in 11 ALS patients. With the soy test meal, glucagon levels were elevated in all ALS patients compared with controls: at fasting (237 ± 111 versus 108 ± 46 pg/ml, p < 0.01) and 2 hour (389 ± 94 versus 133 ± 68 pg/ml, p < 0.001), and 2 hours postprandial (379 ± 75 versus 108 ± 53 pg/ml, p < 0.001). Glucagon levels after the casein test meal were also significantly elevated. Insulin was elevated by both test meals. Casein produced significant glucose intolerance.