Regeneration in the CNS is a rare event and is strongly limited to the replacement of so-called oligodendroglial cells and their electrically insulating elements of the axons, called myelin sheaths. This also applies to multiple sclerosis (MS). The team of Prof. Patrick Küry, Department of Neurology, University Hospital Düsseldorf, describes in Lancet EBioMedicine that the corticosteroid medryson is highly effective in promoting the replacement of lost oligodendroglial cells and also in restoring myelin sheaths and thus the electrical insulation of axons. The regeneration effect by Medryson was mediated via a completely unexpected cell type – astrocytes.
The publication on the mouse model study around first author Markley Silva Oliveira Junior, a talented PhD student from Brazil in the Düsseldorf research group, has just been published.
The scientists were able to show for the first time that astrocytes react specifically in situations where myelin structures are damaged and appear in many different subtypes. Some of these phenotypes attempt to support local tissue repair activities, while others are more oriented toward greater tissue destruction and even contribute additionally to lesion formation. Highly complex and dynamic behavior was observed, but this can be directed by the Medryson drug toward protective and regenerative cells and to “tame” neurotoxic astrocyte populations.
These results are unexpected and novel in the field of neuroregeneration in MS.
Original publication:
Silva Oliveira-Junior, M., Schira-Heinen, J., Reiche, L., Han, S., de Amorim, V.C.M., Lewen, I., Gruchot, J., Göttle, P., Akkermann, R., Azim, K., and Küry, P. (2022) Myelin repair is fostered by the corticosteroid medrysone specifically acting on astroglial subpopulations. EBioMedicine 83:104204. doi: 10.1016/j.ebiom.2022.104204. (Online ahead of print).
