Table of Contents Author Guidelines Submit a Manuscript
Journal of Thyroid Research
Volume 2011, Article ID 321030, 17 pages
http://dx.doi.org/10.4061/2011/321030
Review Article

Pleiotropic Effects of Thyroid Hormones: Learning from Hypothyroidism

1Department of Nephrology, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano 1, 14080 Mexico City, DF, Mexico
2Department of Biochemistry, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano 1, 14080 Mexico City, DF, Mexico
3Department of Molecular Biology, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano 1, 14080 Mexico City, DF, Mexico

Received 29 January 2011; Revised 29 March 2011; Accepted 30 March 2011

Academic Editor: Juan Bernal

Copyright © 2011 Martha Franco et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Hypothyroidism induces several metabolic changes that allow understanding some physiopathological mechanisms. Under experimental hypothyroid conditions in rats, heart and kidney are protected against oxidative damage induced by ischemia reperfusion. An increased resistance to opening of the permeability transition pore seems to be at the basis of such protection. Moreover, glomerular filtration rate of hypothyroid kidney is low as a result of adenosine receptors-induced renal vasoconstriction. The vascular tone of aorta is also regulated by adenosine in hypothyroid conditions. In other context, thyroid hormones regulate lipoprotein metabolism. High plasma level of LDL cholesterol is a common feature in hypothyroidism, due to a low expression of the hepatic LDL receptor. In contrast, HDL-cholesterol plasma levels are variable in hypothyroidism; several proteins involved in HDL metabolism and structure are expressed at lower levels in experimental hypothyroidism. Based on the positive influence of thyroid hormones on lipoprotein metabolism, thyromimetic drugs are promising for the treatment of dyslipidemias. In summary, hypothyroid status has been useful to understand molecular mechanisms involved in ischemia reperfusion, regulation of vascular function and intravascular metabolism of lipoproteins.