Plasma asymmetric dimethylarginine concentrations are elevated in obese insulin-resistant women and fall with weight loss.
BACKGROUND
Plasma asymmetric dimethylarginine (ADMA) concentrations are higher in apparently healthy, insulin-resistant (IR) individuals and decrease in response to thiazolidenedione treatment.


OBJECTIVE
The objective of the study was to determine whether ADMA concentrations would also fall when insulin sensitivity is enhanced with weight loss in obese individuals. DESIGN/SETTING/PATIENTS/INTERVENTION: Twenty obese women classified as IR or insulin sensitive (IS) on the basis of their steady-state plasma glucose (SSPG) concentration during the insulin suppression test underwent 12 wk of dietary weight loss.


METHODS
Plasma glucose, insulin, and ADMA were measured at baseline and after weight loss; change in insulin resistance was quantified by repeating the SSPG after the dietary intervention.


RESULTS
Although weight loss was similar in the two groups, significant improvements in SSPG, glucose, and insulin concentrations were confined to the IR group. Baseline plasma ADMA concentrations (mean +/- sd) were higher in IR subjects (1.69 +/- 0.44 vs. 1.18 +/- 0.45 micromol/liter, P = 0.02) and decreased to 1.20 +/- 0.22 micromol/liter (P < 0.001) with weight loss. In contrast, ADMA levels did not change with a similar extent of weight loss in the IS group.


CONCLUSIONS
Plasma ADMA levels are higher in obese, IR women than in equally obese, IS women and decrease in response to weight loss when associated with enhancement of insulin sensitivity.
McLaughlin
Tracey
T
Division of Endocrinology, Stanford University School of Medicine, Stanford, California 94305-5103, USA.
Stühlinger
Markus
M
Lamendola
Cindy
C
Abbasi
Fahim
F
Bialek
Joan
J
Reaven
Gerald M
GM
Tsao
Philip S
PS
D000328:Adult; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D004038:Diet, Reducing; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000178:diet therapy; D015431:Weight Loss / Q000502:physiology*
D001786:Blood Glucose; D007328:Insulin; C487735:dimethylarginine; D001120:Arginine