Unexpected central role of the androgen receptor in the spontaneous regeneration of myelin

Myelin, which protects nerve fibers and speeds up electrical signals, can be repaired after damage in a process called remyelination. This study found that testosterone and its receptor, the androgen receptor (AR), play a crucial role in this remyelination process in the central nervous system (CNS). When the spinal cords of male mice were demyelinated, those without testes or a functional AR showed impaired astrocyte recruitment. Astrocytes are important for oligodendrocyte-mediated remyelination, which is the normal type of remyelination in the CNS. In the absence of astrocytes, axons were remyelinated by cells that resemble Schwann cells, which are typically found in the peripheral nervous system. This suggests that testosterone and AR promote the recruitment of astrocytes, which in turn favors the normal oligodendrocyte-mediated remyelination in the CNS.

• 1
  Testosterone and the androgen receptor (AR) are essential for the recruitment of astrocytes into demyelinated lesions in the CNS of male mice.
• 2
  In the absence of testosterone or a functional AR, remyelination is preferentially carried out by Schwann cells, resulting in peripheral-type myelin within the CNS.
• 3
  Testosterone increases the proliferation and differentiation of oligodendrocyte progenitors (OPs) in the presence of astrocytes, promoting CNS myelin regeneration.