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Myelin loss limits neurological recovery and myelin regeneration and is critical for restoration of function. We recently discovered that global knockout of the thrombin receptor, also known as Protease Activated Receptor 1 (PAR1), accelerates myelin development. Here we demonstrate that knocking out PAR1 also promotes myelin regeneration. Outcomes in two unique models of myelin injury and repair, that is lysolecithin or cuprizonemediated demyelination, showed that PAR1 knockout in male mice improves replenishment of myelinating cells and remyelinated nerve fibers and slows early axon damage. Improvements in myelin regeneration in PAR1 knockout mice occurred in tandem with a skewing of reactive astrocyte signatures towards a prorepair phenotype. In cell culture, the pro-myelinating effects of PAR1 loss-of-function are consistent with possible direct effects on the myelinating potential of oligodendrocyte progenitor cells (OPCs), in addition to OPC-indirect effects involving enhanced astrocyte expression of pro-myelinating factors, such as BDNF. These findings highlight previously unrecognized roles of PAR1 in myelin regeneration, including integrated actions across the oligodendrocyte and astroglial compartments that are at least partially mechanistically linked to the powerful BDNF-TrkB neurotrophic signaling system. Altogether findings suggest PAR1 may be a therapeutically tractable target for demyelinating disorders of the CNS. [ABSTRACT FROM AUTHOR]