Creatine in type 2 diabetes: a randomized, double-blind, placebo-controlled trial.
Creatine supplementation improves glucose tolerance in healthy subjects.


OBJECTIVE
The aim was to investigate whether creatine supplementation has a beneficial effect on glycemic control of type 2 diabetic patients undergoing exercise training.


METHODS
A 12-wk randomized, double-blind, placebo-controlled trial was performed. The patients were allocated to receive either creatine (CR) (5 g·d) or placebo (PL) and were enrolled in an exercise training program. The primary outcome was glycosylated hemoglobin (HbA1c). Secondary outcomes included the area under the curve of glucose, insulin, and C-peptide and insulin sensitivity indexes. Physical capacity, lipid profile, and GLUT-4 protein expression and translocation were also assessed.


RESULTS
Twenty-five subjects were analyzed (CR: n=13; PL: n=12). HbA1c was significantly reduced in the creatine group when compared with the placebo group (CR: PRE=7.4 ± 0.7, POST=6.4 ± 0.4; PL: PRE=7.5 ± 0.6, POST=7.6 ± 0.7; P=0.004; difference=-1.1%, 95% confidence interval=-1.9% to -0.4%). The delta area under the curve of glucose concentration was significantly lower in the CR group than in the PL group (CR=-7790 ± 4600, PL=2008 ± 7614; P=0.05). The CR group also presented decreased glycemia at times 0, 30, and 60 min during a meal tolerance test and increased GLUT-4 translocation. Insulin and C-peptide concentrations, surrogates of insulin sensitivity, physical capacity, lipid profile, and adverse effects were comparable between the groups.


CONCLUSIONS
Creatine supplementation combined with an exercise program improves glycemic control in type 2 diabetic patients. The underlying mechanism seems to be related to an increase in GLUT-4 recruitment to the sarcolemma.
Gualano
Bruno
B
Laboratory of Applied Nutrition and Metabolism, School of Physical Education and Sports, University of São Paulo, São Paulo, Brazil. gualano@usp.br
DE Salles Painneli
Vitor
V
Roschel
Hamilton
H
Artioli
Guilherme Giannini
GG
Neves
Manoel
M
De Sá Pinto
Ana Lúcia
AL
Da Silva
Maria Elizabeth Rossi
ME
Cunha
Maria Rosária
MR
Otaduy
Maria Concepción García
MC
Leite
Claudia Da Costa
Cda C
Ferreira
Júlio César
JC
Pereira
Rosa Maria
RM
Brum
Patrícia Chakur
PC
Bonfá
Eloisa
E
Lancha
Antonio Herbert
AH
D001786:Blood Glucose / Q000032:analysis / Q000187:drug effects*; D015153:Blotting, Western; D003401:Creatine / Q000008:administration & dosage* / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism; D019587:Dietary Supplements; D004311:Double-Blind Method; D002149:Energy Intake / Q000502:physiology; D015444:Exercise / Q000502:physiology; D005260:Female; D006442:Glycated Hemoglobin / Q000008:administration & dosage; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D010725:Phosphocreatine / Q000032:analysis
D001786:Blood Glucose; D003401:Creatine; D006442:Glycated Hemoglobin; D008055:Lipids; D010725:Phosphocreatine; C517652:hemoglobin A1c protein, human