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DOI: 10.1055/s-0029-1237702
© J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York
Alpha-lipoic Acid Improves Endothelial Dysfunction in Patients with Subclinical Hypothyroidism
Publikationsverlauf
received 22.04.2009
first decision 25.06.2009
accepted 30.07.2009
Publikationsdatum:
16. Februar 2010 (online)
![](https://www.thieme-connect.de/media/eced/201009/lookinside/thumbnails/10.1055-s-0029-1237702-1.jpg)
Abstract
Objective: Many studies showed that impairment of flow-mediated endothelium-dependent arterial dilation (FMD) exists in patients with subclinical hypothyroidism (sHT). The crucial mechanism of this endothelial dysfunction remain unclear. We hypothesized that oxidative stress may be partially responsible for the impairment in FMD in patients with sHT. Thus, the present study was designed to assess whether the antioxidant alpha-lipoic acid can improve endothelial dysfunction in patients with sHT.
Patients and methods: Forty women with newly diagnosed sHT and 18 healthy women with euthyroid status were enrolled. Patients were randomized into 2 groups to receive no treatment (n=20), alpha-lipoic acid (n=20) for 3 weeks. We measured the FMD at baseline and after 3 weeks.
Results: FMD in alpha-lipoic acid and no-treatment group were 3.92% and 4.02%, respectively, which were significantly lower than that in controls (5.64%) (p<0.001). After 3 weeks treatment, compared with before treatment in sHT patients, plasma thiobarbituric acid reactive substances (TBARS) levels decreased significantly in alpha-lipoic acid group (p<0.001), and remain unchanged in no-treatment group (p>0.05). FMD improved markedly (4.82%) in alpha-lipoic acid group (p<0.01), and remain unchanged in no-treatment group (p>0.05). The absolute changes in FMD showed significant negative correlation with the changes in TBARS (r=−0.773, p<0.001).
Conclusion: Our data showed that sHT patients exists impaired endothelial function, and antioxidant alpha-lipoic acid can improve endothelial function, through decrease of oxygen- derived free radicals.
Key words
subclinical hypothyroidism - endothelial dysfunction - antioxidant
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Correspondence
XiangGD MD, PhD
Department of Endocrinology
Wuhan General Hospital of Guangzhou Command
Wuluo Road 627
Wuhan 430070
Hubei Province
P. R. China
Telefon: +8602768878410
Fax: +8602768878410
eMail: Guangda64@hotmail.com