Endocrine Abstracts

Thyroid hormones (T₄ and T₃) have a major role in brain development, and their deficits during critical stages during the fetal and neonatal periods may cause profound intellectual and neuromotor deficits. A particular example is the X-linked Allan-Herndon-Dudley syndrome, caused by mutations of the cellular transporter for thyroid hormone MCT8 (SLC16A2). In this presentation I will first review the pathophysiology of thyroid hormone transport and metabolism in the brain, and the interaction between the main players, i.e., the transporters, the deiodinases, and the nuclear receptors. Then I will review how thyroid hormone (T₃) acts at the genomic level by regulating the expression of many genes. In particular I will present recent data from our laboratory using primary mouse cerebrocortical cells in culture that has permitted the identification of primary and secondary gene responses after T₃ addition. Genomic data indicate that the role of thyroid hormone is to facilitate the transition from a fetal pattern to a mature or adult pattern of gene expression.

Disclosure: This work was supported by the Plan Nacional grant SAF2011-25608, the Center for Biomedical Research on rare Diseases, and the ERA-Net E-Rare2, the European Research Projects on rare Diseases.