Effects of diet-induced moderate weight reduction on intrahepatic and intramyocellular triglycerides and glucose metabolism in obese subjects.
BACKGROUND
Although moderate weight reduction is recommended as primary therapy of metabolic syndrome, little information is known regarding metabolic changes associated with moderate weight reduction in nondiabetic obese subjects.


OBJECTIVE
The aim of this study was to determine the effects of a moderate weight reduction program on intracellular lipid and glucose metabolism in muscle and liver.


METHODS
Data for 13 nondiabetic obese subjects were evaluated.


METHODS
Subjects were put on a 3-month mildly hypocaloric diet therapy (approximately 35 kcal/kg of ideal body weight).


METHODS
Intrahepatic lipid (IHL) and intramyocellular lipid were measured by using (1)H magnetic resonance spectroscopy. Peripheral insulin sensitivity and splanchnic glucose uptake were evaluated by euglycemic-hyperinsulinemic clamp with oral glucose load.


RESULTS
Diet therapy for 3 months resulted in 6% reduction in body weight (from 99.9 +/- 7.3 to 93.8 +/- 6.6 kg, P < 0.0001). This change was accompanied by reduction of plasma glucose and insulin excursions during 75-g oral glucose tolerance tests, decrease in diastolic blood pressure, glycated hemoglobin, serum low-density lipoprotein cholesterol, and triglyceride. These changes were also accompanied by a decrease in IHL (from 12.9 to 8.2%, P < 0.01) and increase in splanchnic glucose uptake (from 13.5 to 35.0%, P < 0.03). On the other hand, the diet program did not affect intramyocellular lipid or glucose infusion rate during euglycemic hyperinsulinemic clamp.


CONCLUSIONS
Our results suggest that moderate weight reduction in obese subjects decreased IHL and augmented splanchnic glucose uptake. This mechanism is at least in part involved in improvement of glucose metabolism by moderate weight reduction in obese subjects.
Sato
Fumihiko
F
Department of Medicine, Metabolism, and Endocrinology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Tamura
Yoshifumi
Y
Watada
Hirotaka
H
Kumashiro
Naoki
N
Igarashi
Yasuhiro
Y
Uchino
Hiroshi
H
Maehara
Tadayuki
T
Kyogoku
Shinsuke
S
Sunayama
Satoshi
S
Sato
Hiroyuki
H
Hirose
Takahisa
T
Tanaka
Yasushi
Y
Kawamori
Ryuzo
R
D000273:Adipose Tissue / Q000378:metabolism; D015992:Body Mass Index; D004038:Diet, Reducing; D005947:Glucose / Q000378:metabolism*; D015309:Glucose Clamp Technique; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D050356:Lipid Metabolism / Q000502:physiology; D008099:Liver / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D032342:Muscle Cells / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism; D009765:Obesity / Q000178:diet therapy / Q000378:metabolism*; D014280:Triglycerides / Q000378:metabolism*; D015431:Weight Loss / Q000502:physiology*
D014280:Triglycerides; D005947:Glucose