Alex Chen

New Stars in Neural Circuits: Astrocytes Guide Brain State Changes - Harvard University - Department of Molecular & Cellular Biology Astrocytes, the most abundant non-neuronal cell type in the brain, have traditionally been thought of as passive supporters of neuronal circuits. However, in recent years, work from many […]

New Stars in Neural Circuits: Astrocytes Guide Brain State Changes 🧪🧠 #AcademicSky
www.mcb.harvard.edu/department/n... @alexbchen.bsky.social @marcduque.bsky.social @mishaahrens.bsky.social @rachellegaudet.bsky.social @dulaclab.bsky.social @harvardbrainsci.bsky.social @scinews.bsky.social

✨Once thought to play a supporting function in the brain, new research led by @alexbchen.bsky.social & @mishaahrens.bsky.social shows non-neuronal astroglial cells perform a leading role in regulating the activity of neurons and their connections. 🧠
🔗 www.janelia.org/news/on-the-...

Thanks Nathalie!

Thanks Emre!

Thanks!

Astrocytes have long been conceived as passive support player cells in the brain. But today @science.org (via 3 reports) they got a big upgrade for their active role in neuromodulation and control of brain function
www.science.org/doi/10.1126/...

Astrocytes, hidden puppet masters of the brain Astrocyte signaling pathways influence neuronal networks and behavioral responses to neuromodulators

Finally, thank you to
@caglaeroglu.bsky.social for the wonderful perspective piece highlighting all three papers! science.org/doi/10.1126/... /end

It appears possible that an ancient role for the NAP motif may have been to implement inhibition to counteract prolonged, perhaps runaway excitation. Nevertheless, continuing to identify circuits and behavioral contexts recruiting this pathway is an exciting future direction. 7/8

In our study, the NAP motif seems to mediate feedforward inhibition: it is activated by contexts requiring strong activation of circuits during futility-induced struggle to prevent prolonged futile struggling. 6/8

That similar pathways exist in flies, fish, and mammals suggests the existence of an evolutionarily conserved, canonical norepinephrine-astrocyte-purinergic signaling motif (NAP motif?) 5/8

GPCR signaling gates astrocyte responsiveness to neurotransmitters and control of neuronal activity How astrocytes regulate neuronal circuits is a fundamental question in neurobiology. Specifically, how astrocytes respond to different neurotransmitters in vivo and how they affect downstream circuit ...

The second by @kevinguttenplan.bsky.social
in Marc Freeman's lab on gating of astrocyte responses to many transmitters by tyramine (an invertebrate norepinephrine analog) in flies, building on earlier work from the lab on astrocytes and ATP in larval fly behavior. science.org/doi/10.1126/... 4/8

Norepinephrine signals through astrocytes to modulate synapses Locus ceruleus (LC)–derived norepinephrine (NE) drives network and behavioral adaptations to environmental saliencies by reconfiguring circuit functional connectivity, but the underlying synapse-level...

Our paper is published back-to-back with two other fantastic papers, one by Katie Lefton in Thomas Papouin's lab at WUSTL on astroglial mediation of NE's effects on synapses in mice. science.org/doi/10.1126/... 3/8

We find that astroglia respond to norepinephrine and release ATP during behavioral futility, and the ATP metabolite adenosine activates neurons to cause passivity. 2/8

Norepinephrine changes behavioral state through astroglial purinergic signaling Both neurons and glia communicate through diffusible neuromodulators; however, how neuron-glial interactions in such neuromodulatory networks influence circuit computation and behavior is unclear. Dur...

Excited to share that the astrocyte-centered half of my thesis work is now out @science.org ! With @mishaahrens.bsky.social and @marcduque.bsky.social
science.org/doi/10.1126/... 1/8

Fast, accurate, and versatile data analysis platform for the quantification of molecular spatiotemporal signals AQuA2 is a powerful data analysis platform that decomposes time-lapse imaging datasets into elementary signaling events, allowing for accurate quantification of spatiotemporal molecular activity patte...

Excited that my co-first author manuscript is now published! Special shoutout to Xuelong Mi in Guoqiang Yu's group, who did all of the development of this fantastic tool, which I’ve applied to segment neuromodulatory and astroglial calcium signals. www.cell.com/cell/fulltex...

What a way to kick off our grad student NeuroMEETS series! Thank you @alexbchen.bsky.social for visiting and sharing your research into the mechanisms of behavioral switching during frustration and futility-induced giving up.
🔎 Want to learn how you can be part of NeuroMEETS? buff.ly/YG2udIf

2025 will be the year of astrocytes 😌