Rate My Professor Ragnhildur Thora Karadottir

Professor Ragnhildur Thora Karadottir is Professor in Cellular Neuroscience in the Department of Veterinary Medicine at the University of Cambridge and Principal Investigator at the Cambridge Stem Cell Institute. Holding a PhD, she has held her position at the University since 2007. Her research centers on neurotransmitter signalling to oligodendrocytes and their progenitor cells in health and disease. The laboratory examines how oligodendrocyte precursor cells generate myelin during development and in pathological conditions including multiple sclerosis, spinal cord injury, stroke, cerebral palsy, and ageing-associated disorders. Oligodendrocyte precursor cells, which constitute 5% of adult brain cells and serve as a primary proliferative stem cell population capable of generating neurons and glia, express neurotransmitter receptors such as NMDA receptors and receive synaptic inputs from neuronal axons. This enables them to detect alterations in neuronal activity, which in turn governs their differentiation into myelinating oligodendrocytes, thereby modulating white matter plasticity and remyelination processes.

Key findings from her group include the identification of neuronal activity-dependent myelin repair mechanisms following stroke through glutamate signalling, the presence of NMDA receptors on oligodendrocytes activated during ischaemia, and the emergence of regional diversity and heterogeneity in oligodendrocyte precursor cells with ageing. Her influential publications encompass 'NMDA receptors are expressed in oligodendrocytes and activated in ischaemia' (Nature, 2005), 'Spiking and nonspiking classes of oligodendrocyte precursor glia in CNS white matter' (Nature Neuroscience, 2008), 'Neuregulin and BDNF induce a switch to NMDA receptor-dependent myelination by oligodendrocytes' (PLoS Biology, 2013), 'Neuronal activity regulates remyelination via glutamate signalling to oligodendrocyte progenitors' (Nature Communications, 2015), and 'Oligodendrocyte progenitor cells become regionally diverse and heterogeneous with age' (Neuron, 2019). These contributions have significantly advanced knowledge of neuron-glia interactions and potential interventions for white matter diseases.