Lucas Benoit

How astrocyte leaflets (which envelop neuron-neuron synapses) integrate signals from multiple synapses

📹 @bleuncoaist.bsky.social, Ines Hristovska, Nicolas Liaudet et al Grenoble Institut Neurosciences; University of Lausanne in Cell @cellpress.bsky.social

➡️ bpod.org.uk/archive/2025...

Thrilled to share that our article has just been published in Cell!
This work is the result of six years of dedication and an incredible team effort.

English version of the INSERM press release : presse.inserm.fr/en/astrocyte...

Article link : www.sciencedirect.com/science/arti...

A single leaflet can integrate signals from a dozen (or more) different neurons. These integrated calcium events can influence communication among the wrapped synapses. #Integration

Key finding: Leaflets envelop synapses, contain ER fragments, and link via gap junctions to form a functional domain. When nearby synapses fire, small calcium rises occur; integrated activity produces larger calcium events. #Synapse

Why now? The finest astrocyte regions at synapses are tiny and hard to image. The team combined volumetric EM (nanoscale) with a custom optical method to capture calcium changes in very small volumes. #Microscopy

Background: Since the 1990s, calcium has been known as astrocytes’ messenger. Calcium signals can trigger the release of transmitters that tune synaptic strength. The ER stores and releases this calcium. #Calcium #ER

Published in Cell (Sep 24, 2025), the study shows astrocytes don’t just modulate one synapse; they coordinate multiple inputs across space and time—active computation, not passive support. #ComputationalBrain

Right panel: a 3D rendering by artist Rémi Greco, built from real data (© Lucas Benoit & Rémi Greco / GIN). Visualization helps reveal how leaflets sit among synapses. #SciArt #3D

Each astrocyte touches several neurons and >100,000 synapses. At the microscopic level, dozens of synapses cluster around a single astrocytic structure called a “leaflet,” which can detect and integrate multiple inputs. #Brain

Astrocytes, the brain’s unexpected conductors.
A Franco-Swiss team shows these glial cells integrate signals from many neurons—a conceptual shift in how we think the brain computes.
#Neuroscience #Astrocytes #Glia #Cell