Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.64898/2026.10.17.759861

Spatiotemporal transcriptomic dynamic across the auditory pathway from young to old age in 5xFAD Alzheimer disease mice

Kong, Y.·Zhai, T.-Y.·Zhao, H.-B.
View original source ↗Export metadata ↓

Abstract

Auditory dysfunction can precede clinical dementia, but the molecular progression of Alzheimer disease (AD) pathology from the sensory periphery to auditory cortex remains poorly resolved. We performed bulk RNA sequencing of auditory cortex (AC), inferior colliculus (IC), cochlear nucleus (CN), and cochlea from 5xFAD and wild-type mice at postnatal day 50 (P50), 8 months, 11 months, and 16 months. Age-specific genotype effects and Genotype x Age interactions were evaluated using DESeq2, followed by Hallmark, KEGG, and Gene Ontology gene-set enrichment analyses and a cross-region synthesis of interaction trajectories. At P50, AC, IC, and cochlea showed coordinated suppression of mitochondrial metabolism, translation, RNA processing, and proteostasis, whereas CN displayed the opposite metabolic and biosynthetic profile together with reduced synaptic and adhesion programs. At 8 months, inflammatory interactions converged across all four regions, including interferon, complement, IL6-JAK-STAT3, and broader immune-response pathways. This coordination fractured at 11 months: AC and IC retained inflammatory and negative synaptic shifts, whereas CN and cochlea frequently changed in the opposite direction, including transient positive shifts in synaptic programs. By 16 months, immune interactions converged again, while metabolic, proteostatic, and synaptic trajectories remained region dependent; CN opposed AC, IC, and cochlea in several major metabolic programs. These findings define a distributed, asynchronous response rather than a monotonic bottom-up or top-down progression. The resulting spatiotemporal map links early metabolic stress, intermediate central-peripheral decoupling, and late inflammatory convergence, providing a molecular framework for evaluating peripheral to central auditory gain and temporal-processing measures as candidate indicators of AD progression.

Explore related subjects

neurosciencePreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Kong, Y., Zhai, T.-Y., Zhao, H.-B.. 2026-10-18. Spatiotemporal transcriptomic dynamic across the auditory pathway from young to old age in 5xFAD Alzheimer disease mice. https://doi.org/10.64898/2026.10.17.759861

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

KEEP EXPLORING

Related preprints

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↗
bioRxiv2026

Disrupting SORL1-retromer endosomal recycling in mice drives the age-dependent neurodegenerative signature of Alzheimer's disease

MRI studies have mapped the atrophic signature that distinguishes Alzheimer's disease (AD), isolating regions differentially vulnerable to its age-dependent neurodegenerative process. We test the hypothesis that an endosomal recycling pathway regulated by the interaction of SORL1 with retromer, which is pathogenically disrupted in AD, might drive the neurodegenerative process via multiple yearlong studies in over 140 wildtype and SORL1 deficient mice, modeling AD's causative mutations. MRI studies revealed that SORL1 deficiency induced an age-dependent AD-pattern of atrophy, centered on the trans-entorhinal cortex, and that atrophy was prevented by SORL1 restoration, secondary to overexpressing the retromer protein VPS26b. Postmortem studies validated that the atrophy reflects neuronal loss. Proteomic profiling revealed that the atrophy is associated with reductions in cell death suppressors, one of which was then found deficient in the trans-entorhinal cortex of AD patients. Besides supporting the hypothesis, taken together with other findings, the results suggest that SORL1-retromer disruptions represent a therapeutically-amenable common 'neurodegeneration pathway' in AD.

neuroscience↗