Low-dose growth hormone treatment combined with diet restriction decreases insulin resistance by reducing visceral fat and increasing muscle mass in obese type 2 diabetic patients.
OBJECTIVE
To evaluate the effects of low-dose growth hormone (GH) therapy combined with diet restriction on changes in body composition and the consequent change in insulin resistance in newly-diagnosed obese type 2 diabetic patients.


METHODS
Double-blind and placebo-controlled trial of 25-kcal/kg IBW diet daily with GH (n=9; rhGH, 0.15 IU/kg body weight/week) or placebo (n=9) for 12 weeks.


METHODS
Eighteen newly-diagnosed obese type 2 diabetic patients (age 42--56 y, body mass index 28.1+/-2.7 kg/m(2)).


METHODS
Body composition and fat distribution parameters (by bioelectrical impedance analyzer and CT scans), serum IGF-1; serum glucose, insulin and free fatty acid (FFA) during oral glucose tolerance test (OGTT); HbA(1c); serum lipid profiles; and glucose disposal rate (GDR) by euglycemic hyperinsulinemic clamp at baseline and after treatment.


RESULTS
The fraction of body weight lost as fat lost was significantly greater (0.98+/-0.39 vs 0.52+/-0.32 kg/kg, P<0.05) and visceral fat area was decreased more in the GH-treated group compared to the placebo-treated group (27.9 vs 21.6%, P<0.05). Lean body mass and muscle area were reduced in the placebo-treated group, whereas an increase in both was observed in the GH-treated group. GDR the was significantly increased in only the GH-treated group (4.67+/-1.05 vs 6.95+/-0.91 mg/kg/min, P<0.05). The GH-induced increase in GDR was positively correlated with the decrease in the ratio of visceral fat area/muscle area (r=0.588, P=0.001). Serum glucose levels and insulin- and FFA-area under the curve during OGTT and HbA(1c) were significantly decreased after GH treatment. LDL-cholesterol level was decreased in only the GH-treated group.


CONCLUSIONS
Low-dose GH treatment combined with dietary restriction resulted not only in a decrease of visceral fat but also in an increase of muscle mass with a consequent improvement of the insulin resistance observed in obese type 2 diabetic patients.
Nam
S Y
SY
Division of Endocrinology, Department of Internal Medicine, YongDong Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. namsy16@yumc.yonsei.ac.kr
Kim
K R
KR
Cha
B S
BS
Song
Y D
YD
Lim
S K
SK
Lee
H C
HC
Huh
K B
KB
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000187:drug effects*; D003920:Diabetes Mellitus / Q000378:metabolism / Q000628:therapy*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000628:therapy*; D004038:Diet, Reducing; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D007333:Insulin Resistance; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D009765:Obesity
D001786:Blood Glucose; D008055:Lipids; D013006:Growth Hormone