Blood vessels control brain growth

Blood vessels play a vital role in stem cell reproduction, enabling the brain to grow and develop in the womb, reveals new UCL research in mice. The study, published in the Proceedings of the National Academy of Sciences and funded by Wellcome, shows that blood vessels can increase the number of neural stem cells inside a living organism. This could be important for the design of stem cell-based therapies that aim to regenerate diseased or damaged parts of the nervous system. In the developing brain, new neurons are produced by neural stem cells in 'neurogenic' areas, where they have to be instructed when and how often they should divide or what type of progeny they should produce. Until now, however, the signals responsible for these instructions have remained elusive. 'We found that blood vessels play a vital role in telling neural stem cells when and how to reproduce,' explains lead author Mathew Tata (UCL Institute of Ophthalmology). 'We examined neural stem cell behaviour in the brainstem of mice lacking the blood vessel protein NRP1, because this part of the brain is particularly important to control fundamental processes such as breathing and heart rate.