The developing post-natal cerebral vasculature, by Nicolas Renier

The developing post-natal cerebral vasculature

Summary
The brain is densely perfused by the vascular network, which provides nutrients and oxygen to support neuronal function. The architecture of the cerebral vasculature addresses specific constrains of the neural tissues, including the near absence of energy storage and very high metabolic demand. Despite the clear observation that both the vascular density and the metabolic demands are heterogenous across the brain, whether and how neuronal activity controls the vascular topology is still debated for several reasons: first, there is no correlation between the densities of neurons and blood vessels. Second, the organization of the vascular and neuronal networks don’t match closely. Third, there is disagreement in the literature on whether modulating neuronal activity levels can lead to a remodeling of the vasculature or not. To better understand the relationship between the metabolic need of the different neural cell types and the topology of the adult vascular network, we built a 3D developmental atlas of the brain vasculature. For this, we generated the annotation maps and templates for the developing mouse brain to align vascular datasets onto. We next optimized a series of computational tools to measure and classify the organization of the different brain regions. We used these tools to generate a system’s view of the developmental trajectories for the various brain regions. Finally, we tested in different models of neuronal activity modulation its impact on the development and maintenance of the network. This work reveals how the vascular network can cater differently to the metabolic needs of both the developing and adult brain, and how cerebral networks shape the development and maintenance of the cerebral vasculature.

Short Biography
Dr. Nicolas Renier started his doctoral training in 2007 at the Vision Institute in Paris in the laboratory of Alain Chédotal. His work detailed the importance of crossed axons in the formation of functional circuits and maps in the brain. He then moved to the laboratory of Marc Tessier-Lavigne in 2012 at the Rockefeller University in New York City where he co-developed methods to map the brain and other organs in 3D using tissue clearing and light sheet microscopy. These tools enable fast and streamlined 3D analysis of neuronal activity and axonal projection patterns in the mouse brain.
Nicolas started his own laboratory in 2017 at the Paris Brain Institute, where he is developing a research program to understand the mechanisms and physiological impact of cerebral plasticity during development and in the adult life. His independent work led so far to 1) the development of a methodology to generate whole brain maps of the microvascular cerebral network in the mouse in physiological and pathological conditions and 2) How brain plasticity during pregnancy can shape some maternal behaviors.