Endocrine Abstracts

Thyroid hormone is a critical regulator of brain development, function, and metabolism. The hypothalamo-pituitary–thyroid (HPT) axis controls thyroid hormone secretion of the thyroid gland. In humans, this process generates predominantly thyroxine, a stable prohormone that cannot efficiently ligand nuclear thyroid hormone receptors prior to its activation to T3. Since the HPT axis is not capable for rapid and tissue-specific control of thyroid hormone levels, a...

Thyroid hormone (TH) actions and metabolism are intracellular events that require the transport of TH across the plasma membrane. This process is facilitated by TH transporters of which the monocarboxylate transporter 8 (MCT8) has been most intensively analyzed. In humans, inactivating mutations in the X-linked MCT8 gene are associated with a severe form of psychomotor retardation in combination with abnormal serum TH parameters. The clinical picture (also known as Al...

Oxidative processes are of special significance in the thyroid gland, as they are indispensable for thyroid hormone synthesis. It is estimated that huge amount of reactive oxygen species, especially of hydrogen peroxide (H2O2), are formed in the thyroid under physiological conditions. Also iron, present in thyroperoxidase, is required for thyroid hormone synthesis. Both, H2O2 and iron, constitute substrates of the most basic reaction...