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Pioglitazone improves endothelium-dependent vasodilation in hypertensive patients with impaired glucose tolerance in
Takayuki Hidaka1, Keigo Nakagawa, Chikara Goto
1Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
Atherosclerosis
|January 13, 2010
Summary
Pioglitazone treatment improved endothelial function in hypertensive patients with impaired glucose tolerance (IGT). This was achieved by increasing nitric oxide bioavailability and reducing oxidative stress.
Area of Science:
- Cardiovascular Medicine
- Endocrinology
- Pharmacology
Background:
- Hypertension and impaired glucose tolerance (IGT) are associated with endothelial dysfunction.
- Endothelial dysfunction contributes to cardiovascular complications in these patients.
Purpose of the Study:
- To investigate the effect of pioglitazone on endothelial function in hypertensive patients with IGT.
- To compare pioglitazone with amlodipine in this patient population.
Main Methods:
- A 12-week randomized study involving 34 hypertensive patients with IGT.
- Patients were assigned to pioglitazone or amlodipine monotherapy.
- Forearm blood flow (FBF) responses to acetylcholine and sodium nitroprusside were measured.
Main Results:
- Pioglitazone significantly increased FBF response to acetylcholine, indicating improved endothelial nitric oxide-mediated vasodilation.
- Pioglitazone decreased urinary 8-hydroxy-2'-deoxyguanosine excretion, suggesting reduced oxidative stress.
- Amlodipine did not improve acetylcholine-stimulated FBF, and neither drug altered sodium nitroprusside responses.
Conclusions:
- Pioglitazone effectively improves endothelial function in hypertensive patients with IGT.
- The mechanism involves enhanced nitric oxide bioavailability, partly due to decreased oxidative stress.
- Pioglitazone offers a therapeutic benefit beyond blood pressure control in this high-risk group.
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