Pioglitazone decreases plasma angiotensin II concentration in type 2 diabetes.
OBJECTIVE
Adipocytes express all components of the renin-angiotensin system (RAS), and adipocyte RAS regulates adipocyte differentiation and metabolism. Plasma angiotensin II (AII) is a putative marker of adipocyte RAS production. The aim of this study was to investigate the effect of pioglitazone on plasma AII in type 2 diabetes (T2D).


METHODS
Fifty Japanese subjects with T2D were randomly allocated to two groups. One group was administered pioglitazone 30 mg/day (pioglitazone group) and the other group was not given pioglitazone (control group) for 16 weeks. Lipoprotein lipase mass in preheparin serum (LPL mass) was measured as an adipocyte-derived factor and a marker of insulin sensitivity.


RESULTS
In the pioglitazone group, the mean HbA1c decreased (p<0.0001), LPL mass increased (p<0.0001), and plasma AII decreased (p=0.0007), whereas these parameters were unchanged in the control group. The change in plasma AII correlated negatively with the change in LPL mass (r=-0.312) in the pioglitazone group. In the pioglitazone group, the decrease in plasma AII was higher (p=0.0002) and the increase in LPL mass tended to be higher (p=0.0941) in the subgroup with higher baseline plasma AII than that with lower plasma AII.


CONCLUSIONS
The present study indicates that pioglitazone decreases plasma AII associated with an increase in LPL mass in T2D. The insulin-sensitizing effect of pioglitazone may be involved in suppressing adipocyte RAS.
Saiki
Atsuhito
A
Center of Diabetes, Endocrine and Metabolism, Toho University Sakura Medical Center, Chiba 285-8741, Japan.
Ohira
Masahiro
M
Endo
Kei
K
Koide
Nobukiyo
N
Oyama
Tomokazu
T
Murano
Takeyoshi
T
Miyashita
Yoh
Y
Shirai
Kohji
K
D017667:Adipocytes / Q000378:metabolism; D000368:Aged; D000804:Angiotensin II / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents; D007328:Insulin / Q000494:pharmacology; D008071:Lipoprotein Lipase / Q000097:blood; D008297:Male; D008875:Middle Aged; D000077205:Pioglitazone; D045162:Thiazolidinediones / Q000494:pharmacology* / Q000627:therapeutic use; D018631:ras Proteins / Q000096:biosynthesis
D015415:Biomarkers; D007004:Hypoglycemic Agents; D007328:Insulin; D045162:Thiazolidinediones; D000804:Angiotensin II; C548261:LPL protein, human; D008071:Lipoprotein Lipase; D018631:ras Proteins; D000077205:Pioglitazone