Optogenetic stimulation promotes Schwann cell proliferation, differentiation, and myelination in vitro

Abstract Schwann cells (SCs) constitute a crucial element of the peripheral nervous system, by structurally supporting the formation of myelin and conveying vital trophic factors to the nervous system. However, the functions of SCs in developmental and regenerative stages remain unclear. Here, we investigated how optogenetic stimulation (OS) of SCs regulates their development. In SC monoculture, OS substantially enhanced SC proliferation and the number of BrdU+-S100ß+-SCs over time. In addition, OS also markedly promoted the expression of both Krox20 and myelin basic protein (MBP) in SC culture medium containing dBcAMP/NRG1, which induced differentiation. We found that the effects of OS are dependent on the intracellular Ca2+ level. OS induces elevated intracellular Ca2+ levels through the T-type voltage-gated calcium channel (VGCC) and mobilization of Ca2+ from both inositol 1,4,5-trisp…