Biology subjects

Jordi, L.

Publications and source records attributed to Jordi, L..

3 recordsLinked to original sources

bioRxiv2026

Progressive neuronal network reorganisation in glioblastoma drives pathological activity in vitro

Glioblastoma (GBM) is the most aggressive primary brain tumour and is frequently accompanied by severe neurological symptoms, including epilepsy and cognitive impairment. Neurological symptoms often persist after surgical resection, indicating that GBM induces durable and self-sustaining changes in the surrounding neuronal networks. However, the mechanisms by which GBM reshapes network structure and function in the tumour periphery remain poorly understood. We present a compartmentalised in vitro platform enabling long-term coculture of iPSC-derived neurons and primary GBM cells to investigate these changes. Placed on high-density microelectrode arrays, the platform permits longitudinal electrophysiological recordings at single-neuron resolution. Using effective network inference, we find that GBM drives a reproducible structural progression: first toward a hyperconnected, hub-dominated architecture, then a collapse of community structure accompanied by a widespread neuron loss. This evolving structure shapes population dynamics, constraining features such as network burst rate and instantaneous synchrony. The reorganisation also carries computational consequences: signal propagation becomes progressively redundant and synergistic rather than unique. As a result, neurons lose the capacity to encode distinct input combinations independently, and the repertoire of accessible network states contracts. Together, these findings reframe GBM as a driver of neuronal network reorganisation rather than uniform hyperexcitability, and establish a compartmentalised, single-neuron-resolution platform for the longitudinal observation, dissection, and ultimately targeting of the network processes that underlie disease progression.

neuroscience↗

bioRxiv2026

A Microfluidic Platform for Spatiotemporal Dissection of Neurodegeneration Across Hierarchical Human Neural Circuits

Understanding how neurodegenerative diseases initiate and propagate through neural circuits remains a fundamental challenge in neuroscience. The earliest stages occur years before symptoms emerge, making them inaccessible to study in patients. Microfluidic platforms, where neurons communicate across chambers through microchannels accessible only to their axons, have opened new experimental avenues. However, existing models lack the complexity and precision needed to track how individual circuit components respond to focal pathological changes over time. Here we present a 33-chamber cortical network-on-chip integrating human iPSC-derived excitatory neurons, inhibitory neurons, and astrocytes in a six-layer feedforward architecture recapitulating the laminar structure of the neocortex. Amyloid-{beta} is applied globally, while progerin-induced accelerated ageing in a single chamber establishes a defined disease core. Continuous recordings using high-density microelectrode arrays reveal progressive, layer-dependent changes in firing dynamics and network topology. Machine-learning-based feature analysis identifies a multiparametric electrophysiological signature distinguishing healthy from disease-affected chambers, enabling studies of the earliest timepoint at which pathology becomes detectable. This establishes a scalable framework for mechanistic studies of neurodegeneration and identification of electrophysiological biomarkers of disease progression.

neuroscience↗

bioRxiv2025

APOE3 astrocytes can rescue lipid abnormalities and dystrophic neurites of APOE4 human neurons

Lipid abnormalities are emerging as key pathogenic mechanisms in neurodegenerative diseases such as Alzheimers, Parkinsons and Lewy body dementia. Astrocytes in the brain provide APOE proteins and influence neuronal metabolism and health. Using live cell imaging and objective neurite imaging techniques, we show that following induction of cellular lipid (cholesterol and triglycerides) load by inhibiting the lysosomal cholesterol transport protein NPC1 in human neuron-astrocyte co-cultures, that human astrocytes CRISPR edited to be either APOE3 or 4 variants have different effects on rescuing dystrophic neurites, where axons and dendrites of nerve cells become disfigured. APOE3, but not APOE4 or APOEKO, astrocytes prevented cholesterol and lipid induced neurite damage in APOE4 neurons. In the media of APOE3 co-cultured astrocytes with neurons the HDL-like particles were larger and presumably more lipidated than equivalent APOE4 co-cultures. This discovery highlights that living APOE3 astrocytes control key biological mechanisms by physiologically enhancing lipid cellular homeostasis, that can rescue lipid-induced neurite structural abnormalities relevant to Alzheimers disease and neurodegenerative diseases. Significance statementNeurodegenerative diseases like Alzheimers (AD) are often defined by abnormal protein aggregates, but growing evidence points to lipid dysfunction as a key driver, especially in APOE4 carriers, the strongest genetic risk factor for AD. We developed a live cell imaging based human cell culture model using isogenic iPSC-derived neurons and astrocytes (APOE3, APOE4, or APOE knockout) to study this. By blocking cholesterol export via NPC1 inhibition, we mimicked lysosomal lipid stress and found that APOE3 astrocytes uniquely protected APOE4 neurons from forming abnormal neurite swellings. These APOE3 astrocytes produced larger HDL-like particles than APOE4 that supported neuronal lipid balance. Our results show that APOE3 astrocytes can rescue APOE4-related cellular dysfunction, offering a potential path for therapy and biomarker discovery.

neuroscience↗