Preserved GLP-1 effects in a diabetic patient with Cushing's disease.
BACKGROUND
A patient with diabetes mellitus, who participated in a study with intravenous administration of GLP-1, was later found to have Cushing's disease (markedly elevated 24 h urinary cortisol excretion and inadequate suppression of fasting cortisol with 2 mg dexamethasone). His diabetic state disappeared (2 h plasma glucose after 75 g oral glucose 159 mg/dl=IGT) after successful pituitary surgery (normal 24 h urinary cortisol excretion and adequate cortisol suppression with 2 mg dexamethasone).


OBJECTIVE
The present analysis was undertaken to compare GLP-1 actions on fasting glycemia in diabetes mellitus due to Cushing's disease with GLP-1 actions in typical type 2 diabetes.


METHODS
GLP-1 (1.2 pmol/kg/min) and placebo had been infused into ten patients with diabetes mellitus over 4 h in the fasting state. The results from the patient with Cushing's disease (C) were compared to the data from the remaining nine patients with type 2 diabetes (D).


RESULTS
Within 4 h glucose decreased from basal (C: 12.9; D: 12.9+/-0.7 mmol/l) to normal fasting values (C: 5.0; D: 4.9+/-0.4 mmol/l). The stimulation of insulin secretion and suppression of glucagon secretion was similar in the patient with Cushing's disease compared to those with type 2 diabetes.


CONCLUSIONS
The insulinotropic, glucagonostatic and glucose-lowering actions of GLP-1 in a patient with diabetes mellitus due to cortisol excess were similar to actions in typical type 2 diabetes. Therefore incretin mimetics might be a novel therapeutic strategy for the treatment of glucocorticoid-induced diabetes mellitus.
Ritzel
R A
RA
Department of Internal Medicine, Ruhr-University, Knappschafts-Krankenhaus, Bochum, Germany. Robert.Ritzel@med.uni-heidelberg.de
Kleine
N
N
Holst
J J
JJ
Willms
B
B
Schmiegel
W
W
Nauck
M A
MA
D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications* / Q000188:drug therapy / Q000209:etiology; D005260:Female; D052216:Glucagon-Like Peptide 1 / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D006854:Hydrocortisone / Q000009:adverse effects / Q000097:blood; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D047748:Pituitary ACTH Hypersecretion / Q000097:blood / Q000150:complications / Q000175:diagnosis*
D001786:Blood Glucose; D007328:Insulin; D052216:Glucagon-Like Peptide 1; D006854:Hydrocortisone