About Physiology Group

The core research theme of the Physiology group is intercellular Ca2+ communication as a key signaling process in the function of the brain and the cardiovascular system.

Connexins and the channels formed by these proteins contribute to a large extent to intercellular Ca2+ signaling. Gap junctions (channels directly connecting the cytoplasm of neighboring cells) hereby mediate the transfer of primarily IP3 between the cytoplasm of neighboring cells whereas plasma membrane hemichannels (‘half of a gap junction channel’) provide a paracrine release pathway for messenger molecules like ATP. In addition, connexins can have intrinsic signaling functions as well. They have been recently localized in mitochondria, major organelles involved in Ca2+ signaling.

Our work is directed at understanding the role of connexin-mediated communication in several pathophysiological processes including blood vessel reactivity and astrocyte-endothelial signaling in the context of blood-brain barrier disruption, bystander cell death and inflammation, and cardiac ischemia and arrhythmias. A major focus is elucidating the regulatory characteristics of these channels and subsequently developing connexin targeting peptides which selectively modulate gap junctions and/or hemichannels.

This research has shown that connexin-targeting peptides can limit the spread of apoptosis from dying to healthy cells, inhibit an increased blood-brain barrier permeability triggered by pro-inflammatory mediators, and protects against cardiac ischemia/reperfusion injury and cryopreservation-induced injury in human blood vessels. As a consequence, connexin channels should be considered as novel targets for therapeutically influencing disease processes in the brain and the cardiovascular system.