Instructions from the vascular system - directing neural stem cell fate in health and disease.

The vascular system distributes oxygen and nutrients to all tissues in the body. Additionally, the vascular system also functions in hosting and instructing tissue-specific stem and progenitor cells. Both cell- or blood-derived signals from the vascular system regulate stem cell properties in health and disease. Studies in animal models and in human disease have begun to uncover that signals from the vascular system are not merely maintaining the stem cell niche, but also instruct stem cells for repair mechanisms outside their niche. The present article focuses on recent findings about cell- or blood-derived factors in the vascular system supporting stem cell niche maintenance or activation for tissue homeostasis and repair. We highlight the fact that certain aspects of vascular - stem cell communication are conserved between stem cell niches in different tissues. Within this context, we will especially emphasize on a potential role of the altered vascular system after CNS disease in instructing stem cell fate. Understanding the communication between the vascular system and neural stem cells might support the development for new therapeutic approaches for CNS disease.