Pioglitazone increases circulating adiponectin levels and subsequently reduces TNF-alpha levels in Type 2 diabetic patients: a randomized study.
BACKGROUND
Adipocytokines are involved in the development of insulin resistance and endothelial dysfunction in diabetic patients. However, the relationship between these factors remains unclear. We observed a chronological change in circulating adipocytokines and blood pressure levels with administration of oral hypoglycaemic agents in Type 2 diabetic (T2DM) subjects.


METHODS
Thirty poorly controlled T2DM subjects (aged 60.1 +/- 1.5 years, 11 males and 19 females) were randomized into two groups: voglibose (initial dose 0.6 mg/day, increased to 0.9 mg/day) and pioglitazone (initial dose 15 mg/day, increased to 30 mg/day).


RESULTS
Both treatment groups showed a similar improvement in glycaemic control. In pioglitazone-treated patients, circulating adiponectin levels were significantly increased from 4 weeks after the start of treatment, and until the end of the study at 12 weeks. Plasma tumour necrosis factor-alpha (TNF-alpha) levels were significantly decreased only at 12 weeks. In contrast, no significant changes in plasma adiponectin or TNF-alpha levels were observed in voglibose-treated patients. Plasma PAI-1 and leptin levels were not significantly changed at 12 weeks in either treatment group. Pioglitazone significantly decreased systolic and diastolic blood pressure levels at 12 weeks, but voglibose had no effect.


CONCLUSIONS
In summary, pioglitazone caused an immediate increase in circulating adiponectin levels, followed by a reduction of TNF-alpha. The observed increase in circulating adiponectin could be related to decreases in both systolic and diastolic blood pressure.
Shimizu
H
H
Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Japan. hshimizu@showa.gunma-u.ac.jp
Oh-I
S
S
Tsuchiya
T
T
Ohtani
K-I
KI
Okada
S
S
Mori
M
M
D052242:Adiponectin / Q000097:blood*; D000284:Administration, Oral; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure / Q000502:physiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007294:Inositol / Q000008:administration & dosage / Q000031:analogs & derivatives; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D000077205:Pioglitazone; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D045162:Thiazolidinediones / Q000008:administration & dosage*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
D052242:Adiponectin; D001786:Blood Glucose; D007004:Hypoglycemic Agents; D020738:Leptin; D017395:Plasminogen Activator Inhibitor 1; D045162:Thiazolidinediones; D014409:Tumor Necrosis Factor-alpha; D007294:Inositol; C102817:voglibose; D000077205:Pioglitazone