Impaired astrocytic Cx43 syncytial network in lateral habenula affects synaptic connectivity and drives adolescent stress-induced depression

Li, H.; Wang, Q.; Su, Y.; Chen, H.; Wu, Z.; Chen, X.; Wang, C.; Zhao, Y.; Li, D.; Huang, X.; Fu, R.; Huang, W.; Tang, Y.; Niu, J.; Verkhratsky, A.; Yi, C.

doi:10.64898/2026.10.02.756205

bioRxiv · 10.64898/2026.10.02.756205

Impaired astrocytic Cx43 syncytial network in lateral habenula affects synaptic connectivity and drives adolescent stress-induced depression

Li, H.·Wang, Q.·Su, Y.·Chen, H.·Wu, Z.·Chen, X.·Wang, C.·Zhao, Y.·Li, D.·Huang, X.·Fu, R.·Huang, W.·Tang, Y.·Niu, J.·Verkhratsky, A.·Yi, C.

View original source ↗Export metadata ↓

Abstract

Adolescent depression is a major neuropsychiatric disorder induced by early life stress; the underlying cellular mechanisms instigating pathological circuit malformation remain unclear, and, consequently, effective therapeutic strategy is limited. Here, we analysed the contribution of astrocytes to early life stress-induced adolescent depression using a mouse model of parental separation. We identified a previously unrecognised regional specialisation of lateral habenula (LHb) astrocytes, characterised by compact cellular domains, abundant leaflets, and enhanced Cx43 gap junctional coupling. Parental separation selectively reduced astrocytic Cx43 expression and gap junctional communication in the LHb, which was accompanied by profound astrocytic atrophy and loss of leaflets. Single-cell sequencing further revealed that parental separation induces a broad reorganisation of LHb astrocyte transcriptional states, including metabolic, stress-response, and inflammatory programs; moreover, it specifically reduces astrocyte-neuron communication. Consistent with this, we found that structural remodelling of LHb astrocytes affected tripartite synapse geometry, resulting in impaired excitatory and inhibitory synaptic transmission, and neuronal Ca2+ hyperexcitability, all ultimately associated with depressive-like behaviours. Selective knockdown of astrocytic Cx43 in the LHb recapitulated these pathological changes and translated into depressive-like behaviours. Mechanistically, we found that impaired Cx43 gap junctional communication is associated with excessive astrocytic Ca2+ dynamics, resulting in Rac1-GTPase activation and decreased p-Ezrin levels. In vivo inhibition of LHb astrocytic Ca2+ signalling rescued astrocytic atrophy and depressive-like behaviours following parental separation. Together, our findings establish a Cx43-Ca2+-Rac1-p-Ezrin pathway that links gap junction malfunction to structural remodelling of astrocytes and disruption of neuron-astrocyte interactions in the developing LHb. Our study reveals astrocytic Ca2+ dysregulation as an active downstream effector of Cx43 dysfunction and identifies a regionally specialised astrocytic mechanism through which early-life stress disrupts synaptic transmission and neuronal function during adolescence, providing a potential cellular target for intervention in adolescent depression.

Explore related subjects

neuroscience Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Li, H., Wang, Q., Su, Y., Chen, H., Wu, Z., Chen, X., Wang, C., Zhao, Y., Li, D., Huang, X., Fu, R., Huang, W., Tang, Y., Niu, J., Verkhratsky, A., Yi, C.. 2026-10-08. Impaired astrocytic Cx43 syncytial network in lateral habenula affects synaptic connectivity and drives adolescent stress-induced depression. https://doi.org/10.64898/2026.10.02.756205

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Rapid switching of in-phase and anti-phase interhemispheric rhythms within a single theta cycle: a mechanistic explanation

The granular retrosplenial cortex (RSG) supports memory consolidation and spatial navigation. In vivo recordings of local field potential (LFP) from RSG reveal coexisting gamma (30-80 Hz) and spline (100-160 Hz) oscillations, coupled to distinct phases of the background theta ([~]8 Hz) rhythm. Remarkably, bilateral recordings reveal that gamma and splines exhibit divergent interhemispheric phase relationships: gamma is in-phase across hemispheres, while splines are anti-phase. Here, using numerical bifurcation analysis of next-generation neural mass models, we show that RSG oscillations within a single hemisphere can be understood as alternation of PING (pyramidal-interneuron gamma) and ING (interneuron gamma) mechanisms in an excitatory-inhibitory network. Theta-frequency external drive to the inhibitory population switches the network between these two rhythms. Next, we build canonical interhemispheric circuits, composed of two such excitatory-inhibitory modules, delay-coupled across hemispheres. These circuits switch between in-phase gamma and anti-phase splines within a single theta cycle, reproducing the cross-spectral statistics of experimental RSG recordings. Finally, we present analytical results for threshold-linear neural mass models, showing cross-hemispheric phase patterning is governed by the ratio of cross-hemispheric delay to local inhibitory delay; we obtain explicit ranges of this ratio for which RSG-like patterning could be expected. Our work establishes that the unique oscillatory profile of RSG can be explained parsimoniously by minimal interhemispheric circuit configurations and provides a framework for experimental interrogation of interhemispheric rhythms.

neuroscience↗

bioRxiv2026

Brain representations of visual short-term memories during healthy human aging: occipital decline and frontoparietal compensation

Visual short-term memory declines steeply with age, but the link to neural representations of memory content remains unknown. We used fMRI decoding to relate remembered motion-direction representations in visual and frontoparietal cortex to age and performance, in 115 adults, aged 25-87, from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) cohort. Decoding was strongest in visual cortex, but also significant in frontoparietal regions, with different profiles. Visual representations weakened with memory load and age, and statistically mediated age-related performance decline, especially during recall. This coupling, however, weakened with age: some older adults retained stronger visual representations than performance implied, suggesting impaired access to a partially preserved memory trace. Frontoparietal representations, instead, were largely insensitive to load and strengthened with age during maintenance, partially offsetting performance decline. Therefore, interventions to boost VSTM in older adults might target compensatory frontoparietal representations during memory maintenance, and readout of untapped visual representations at recall.

neuroscience↗

bioRxiv2026

Lexical surprisal drives pupil dilation during continuous story listening

The pupil famously adjusts its dilation in response to light, but its role extends far beyond this basic sensory function. Its fluctuations index arousal and mental effort, beyond luminance-related dynamics, making it a sensitive marker of internal cognitive states. A growing body of work shows that these pupil-linked signals extend beyond the visual domain. However, which processes drive pupil responses in more naturalistic settings remains unclear as most evidence comes from tightly controlled paradigms that strip away the richness of real-world experience. Language offers a uniquely powerful window into this question, as it can allow us to create rich paradigms without having any visual, i.e. luminance, confounds. Moreover, language comprehension hinges on continuous prediction: listeners constantly generate expectations about upcoming input, and the discrepancy between expectation and actual input - contextual prediction error, or surprisal - carries measurable cognitive costs. Here, we tested the hypothesis that pupil-linked arousal indexes these linguistic surprisal signals during naturalistic listening. We recorded pupil responses while volunteers listened to naturalistic spoken stories in darkness, which were either intact or reversed. Reversed speech preserves the acoustics of the signal while destroying its intelligibility. Pupil dilation selectively tracked lexical surprisal within a late window of 1,700 to 2,350 milliseconds following word onset, in forward, but not control, backward speech. These findings indicate that pupil-linked arousal is tuned to global, context-dependent processing, tracking the cognitive cost of updating a predictive model during naturalistic listening.

neuroscience↗