Thyroid hormones and brain functions 

Thyroid hormones (TH) are critical for the normal development of the brain as well as for the maintenance of brain functions in adulthood. Our group strives to understand the mechanisms of TH action in neural development and function and how these processes are affected if central TH signaling is perturbed.

In order to act in their target cells, TH require transmembrane transporters, of which the TH transporter MCT8 is of utmost importance in humans. Inactivating mutations in MCT8 lead to a severe psychomotor retardation (also known as Allan-Herndon-Dudley Syndrome), which can be explained by an insufficient supply of TH to the brain. This is accompanied by a number of neurological deficits, such as altered development of the inhibitory GABAergic system in the brain and an increased incidence of epileptic seizures. One main focus of our research is to uncover the (patho)physiological function of MCT8 in particular and TH in general for the development of central neurotransmitter systems in order to understand the increased susceptibility to seizures in MCT8 deficiency.

TH’s effects in the adult brain constitute a second major research focus in our lab. Adult-onset hypothyroidism is associated with learning and memory problems, which can be explained by changes in the hippocampus, the memory center of the brain. A fundamental mechanism is the strong influence of TH on the process of adult hippocampal neurogenesis, the continuous formation of new neurons in the hippocampus. We want to understand how TH influences both hippocampal stem cells and the stem cell niche, thereby regulating learning and memory capacity.