Vascular effects of estrogen in type II diabetic postmenopausal women.
OBJECTIVE
We assessed the effects of estrogen on vascular dilatory and other homeostatic functions potentially affected by nitric oxide (NO)-potentiating properties in type II diabetic postmenopausal women.


BACKGROUND
There is a higher cardiovascular risk in diabetic women than in nondiabetic women. This would suggest that women with diabetes do not have the cardioprotection associated with estrogen.


METHODS
We administered placebo or conjugated equine estrogen, 0.625 mg/day for 8 weeks, to 20 type II diabetic postmenopausal women in a randomized, double-blinded, placebo-controlled, cross-over design.


RESULTS
Compared with placebo, estrogen tended to lower low-density lipoprotein (LDL) cholesterol levels by 15 +/- 23% (p = 0.007) and increase high-density lipoprotein (HDL) cholesterol levels by 8 +/- 16% (p = 0.034). Thus, the ratio of LDL to HDL cholesterol levels significantly decreased with estrogen, by 20 +/- 24%, as compared with placebo (p = 0.001). Compared with placebo, estrogen tended to increase triglyceride levels by 16 +/- 48% and lower glycosylated hemoglobin levels by 3 +/- 13% (p = 0.295 and p = 0.199, respectively). However, estrogen did not significantly improve the percent flow-mediated dilatory response to hyperemia (17 +/- 75% vs. placebo; p = 0.501). The statistical power to accept our observation was 81.5%. Compared with placebo, estrogen did not significantly change E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1 or matrix metalloproteinase-9 levels. Compared with placebo, estrogen tended to decrease tissue factor antigen and increase tissue factor activity levels by 7 +/- 46% and 5 +/- 34%, respectively (p = 0.321 and p = 0.117, respectively) and lower plasminogen activator inhibitor-1 levels by 16 +/- 31% (p = 0.043).


CONCLUSIONS
The effects of estrogen on endothelial, vascular dilatory and other homeostatic functions were less apparent in type II diabetic postmenopausal women, despite the beneficial effects of estrogen on lipoprotein levels.
Koh
K K
KK
Department of Cardiology, Inchon, South Korea. kwangk@ghil.com
Kang
M H
MH
Jin
D K
DK
Lee
S K
SK
Ahn
J Y
JY
Hwang
H Y
HY
Yang
S H
SH
Kim
D S
DS
Ahn
T H
TH
Shin
E K
EK
D001916:Brachial Artery / Q000187:drug effects* / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D018932:Chemokine CCL2 / Q000502:physiology; D008076:Cholesterol, HDL / Q000097:blood / Q000187:drug effects; D008078:Cholesterol, LDL / Q000097:blood / Q000187:drug effects; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology*; D004311:Double-Blind Method; D004357:Drug Synergism; D019040:E-Selectin / Q000187:drug effects; D004966:Estrogens, Conjugated (USP) / Q000494:pharmacology*; D005260:Female; D005342:Fibrinolysis / Q000187:drug effects; D006442:Glycated Hemoglobin / Q000187:drug effects / Q000378:metabolism; D006487:Hemostasis / Q000187:drug effects; D006706:Homeostasis / Q000187:drug effects; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects; D020780:Matrix Metalloproteinase 9 / Q000187:drug effects; D008875:Middle Aged; D009569:Nitric Oxide / Q000502:physiology*; D017395:Plasminogen Activator Inhibitor 1 / Q000502:physiology; D017698:Postmenopause / Q000187:drug effects*; D013925:Thromboplastin / Q000187:drug effects; D014280:Triglycerides / Q000097:blood; D019010:Vascular Cell Adhesion Molecule-1 / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects*
D018932:Chemokine CCL2; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D019040:E-Selectin; D004966:Estrogens, Conjugated (USP); D006442:Glycated Hemoglobin; D018799:Intercellular Adhesion Molecule-1; D020780:Matrix Metalloproteinase 9; D009569:Nitric Oxide; D017395:Plasminogen Activator Inhibitor 1; D013925:Thromboplastin; D014280:Triglycerides; D019010:Vascular Cell Adhesion Molecule-1