Biology subjects

Garcia-Verdugo, J. M.

Publications and source records attributed to Garcia-Verdugo, J. M..

16 recordsLinked to original sources

bioRxiv2026

Cerebral organoids recapitulate interneuron chain migration in the human cortex

The human brain is incomplete at birth, with streams of late-born interneurons migrating into the postnatal cortex. This process is absent in rodents, limiting mechanistic investigation to post-mortem tissue. Here, we show that human cerebral organoids cultured for over six months recapitulate postnatal interneuron migration, enabling its mechanistic and genetic dissection. Live imaging and mathematical modeling revealed that interneurons intrinsically migrate in chains, while astrocyte interactions promote stream organization. Spatial and single-cell transcriptomics identified a distinct molecular signature of human postnatal migratory streams enriched for neurodevelopmental disorder-associated genes. Perturbation of the autism-associated genes CNTN5 and FGF14 differentially disrupted chain organization and migration. Thus, long-term cerebral organoids enable mechanistic analysis of previously inaccessible aspects of postnatal human brain development and their contributions to neurodevelopmental disease.

developmental biology↗

bioRxiv2026

Intracranial Targeting of Cholesterol Processing Reveals a Therapeutic Vulnerability that Reprograms Glioblastoma and Promotes Antitumor Immunity

Glioblastoma (GBM) remains the most lethal primary brain cancer due to its remarkable metabolic plasticity and therapeutic resistance. Here, we identify cholesterol dependency as a therapeutically exploitable vulnerability in GBM using two FDA approved drugs: the H1 histamine antagonist clemastine and the retinoid X receptor agonist bexarotene. Combined treatment induces potent synergistic anti tumor activity across patient-derived glioma models, suppressing proliferation, stemness, and survival at sub IC50 concentrations. Mechanistically, this therapy disrupts cholesterol biosynthesis, transport, and homeostasis, triggering endoplasmic reticulum stress and activation of the unfolded protein response, ultimately leading to autophagy and apoptotic cell death. Orthotopic patient derived glioma models recapitulate these mechanisms in vivo, where local intracranial administration significantly reduces tumor progression and prolongs survival using fourfold lower doses than systemic intraperitoneal delivery. Single cell RNA sequencing revealed activation of regeneration and plasticity programs, accompanied by immune microenvironment remodeling and enhanced inflammatory signaling. Importantly, syngeneic models preserved immune cell composition, supporting future integration with immunotherapeutic strategies. Together, these findings establish cholesterol dysregulation induced metabolic collapse as a promising therapeutic approach for GBM.

cancer biology↗

bioRxiv2026

Specialized Shh-sensing cell with unique cilia and basal body in the forebrain ventricular epithelium

Ependymal (E1) cells, with their tufts of [~]50 motile cilia, line the walls of the brain ventricles and help propel the cerebrospinal fluid (CSF). The CSF is rich in signaling molecules, but the cellular targets that detect these signals and their function remain unknown. Here, we describe a distinct population of ependymal cells (E2) in the forebrain of mice and humans, the majority having only 1 or 2 cilia. These cilia were motile, but unlike E1 cells cilia, their pattern of motility and high expression of Arl13b and Inpp5e suggest a sensory function. E2 cells were characterized by an enormous, donut-like basal body that contained an increased number and size of subdistal appendages. In mice, E2 cells were mostly born in the embryo, but completed their differentiation in juveniles and young adults; they were found at higher densities in regions of high CSF flow and neurogenesis. E2 cilia contained the G protein-coupled receptor Smoothened, which accumulated in their cilia upon exposure to Sonic Hedgehog (Shh). Together, these findings identify E2 cells as a novel CSF-sensing ependymal cell type and provide a cellular target for the CSF signaling.

cell biology↗

bioRxiv2025

Metabolic and transcriptional adaptations to phagocytosis in microglia sustain their functionality and regenerative properties

Phagocytosis of apoptotic cells, or efferocytosis, is a tightly regulated process that ensures tissue homeostasis and prevents mounting inflammatory responses. In the brain parenchyma, it is executed by microglia, which are encumbered by large numbers of apoptotic debris generated during development, in adult neurogenic niches, aging, and brain diseases. Emerging evidence suggest that phagocytosis is not limited to garbage disposal, but triggers adaptations in the phagocytes that may have a functional impact. To test it we developed an in vivo model of superphagocytosis induced by low cranial irradiation (LCI, 2Gy) that specifically induced apoptosis in the neurogenic niche of the adult hippocampus, synchronizing microglia in a phagocytic state within 6h and leading to full clearance by 24h. Single cell RNA sequencing and metabolomics revealed an unexpected oxidative stress in post-phagocytic microglia, accompanied by catabolic shutdown, mitochondrial remodeling, increased expression of galectin 3, and production of polyamines that led to cell death and compensatory proliferation. To test whether these changes impaired subsequent microglial phagocytosis, we used a glioblastoma model treated with sequential irradiation to induce tumor cell apoptosis. The phagocytosis efficiency of tumor-associated microglia/macrophages was comparable in the first and second apoptotic challenge, suggesting that the metabolic remodeling induced by phagocytosis was adaptive and destined to sustain their functionality. Finally, we assessed the functional impact of post-phagocytosis adaptations using galectin 3 deficient mice under LCI. We found that the recovery of the neurogenic niche after LCI strongly depended on galectin 3, demonstrating the regenerative capacity of post-phagocytic microglia. Overall, our data unveils the complexity of post-phagocytosis adaptations in microglia, underscoring their unexplored therapeutic potential in brain disorders.

neuroscience↗

bioRxiv2025

Cerebral Organoids Uncover Mechanisms of Neural Activity Changes in Epileptogenesis

Neurological disorders often originate from progressive brain network dysfunctions that start years before symptoms appear. How these changes emerge in the developing human brain remains elusive due to a lack of tractable model systems. Here, we show a cerebral organoid model of Tuberous Sclerosis Complex (TSC) that recapitulates hallmarks of epileptogenesis in vitro. We compare extracellular recordings of TSC organoids with intraoperative electrocorticography from TSC patients to reveal striking functional similarities, including high-frequency oscillations - an electrical biomarker for epileptogenic tissue. In TSC, a human-specific interneuron sub-type derived from the caudal ganglionic eminence drives network hyper-synchronization through increased spontaneous firing and altered excitability. Inhibiting overproliferation of its progenitors via long-term epidermal growth factor receptor inhibition prevented the onset of this pathological phenotype at functional and morphological levels. Our work shows that organoids allow mechanistic analysis of emerging neural network phenotypes, enabling anti-epileptogenic drug testing in a human brain development model.

neuroscience↗

bioRxiv2025

Monocarboxylate transporter 2 is required for the maintenance of myelin and axonal integrity by oligodendrocytes

Neurodegenerative pathologies including multiple sclerosis (MS) are consistently associated with energy deficit in the central nervous system (CNS). This might directly impact myelinating oligodendrocytes as these are particularly vulnerable to metabolic insults. Importantly, oligodendroglial dysfunction and myelin alterations occur in most, if not all neurodegenerative diseases, and are associated with axonal pathology/loss. Thus, elucidating metabolic mechanisms required for oligodendroglial myelin maintenance and axonal support might be crucial to identify therapeutic targets to achieve neuroprotection. While monocarboxylates are important energy fuels for the CNS, their role in myelinating oligodendrocyte function remains unclear. Here we show that, just like neurons, myelinating oligodendrocytes express high affinity monocarboxylate transporter 2 (MCT2) both in mice and humans, which is downregulated in progressive MS. While deletion of MCT2 in mouse oligodendrocytes did not affect the survival of these cells, it resulted in downregulation of lipid synthesis-associated enzymes and failure of myelin maintenance. Moreover, axonal upregulation of lactate dehydrogenase A concomitant with axonal damage was observed but could be alleviated by ketogenic diet. We conclude that oligodendroglial MCT2 is required for myelin maintenance and axonal support, which becomes altered in progressive MS, but may be compensated for by specific metabolic therapies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/632306v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@2b7b22org.highwire.dtl.DTLVardef@a111fdorg.highwire.dtl.DTLVardef@a410f5org.highwire.dtl.DTLVardef@1556e2f_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2024

Anatomy, histology and ultrastructure of the adult human olfactory peduncle: blood vessel and corpora amylacea assessment

The mammalian olfactory system is responsible for processing volatile chemical stimuli and is composed of several structures including the olfactory epithelium, olfactory bulb, olfactory peduncle (OP), and olfactory cortices. Despite the critical role played by the OP in the transport of information it has remained understudied. In this work, optical, confocal, and electron microscopy were employed to examine the anatomy, histology, and ultrastructure of six human OP specimens (ages 37-84 years). Three concentric layers were identified in coronal sections: the external layer (EL), the axonal layer (AL), and the internal layer (IL). Immunohistochemistry revealed the distribution of neurons and glial cells throughout the OP. Two neuronal morphologies were observed: granule cells and larger pyramidal cells, the latter associated with projection neurons of the anterior olfactory nucleus. Astrocytes were uniformly distributed with a more radial morphology in the EL. Oligodendrocytes were mainly located in the AL. Blood vessels (BVs) were evenly distributed along the OP, with a mean luminal area of 82.9 {micro}m{superscript 2} and a density of 1.26 %, with a significant increase in the IL. CA were abundant, with an average size of 49.3 {micro}m{superscript 2} and a density of 3.23 %. CA clustered near BVs, particularly at tissue edges, with both size and density increasing with age. Notably, CA showed strong associations with astrocytes. This study provides the first detailed qualitative and quantitative data on the internal organization of the human OP, which may contribute to a better understanding of the pathophysiology of some neuropathological disorders.

neuroscience↗

bioRxiv2024

Neural Stem Cell Relay from B1 to B2 cells in the adult mouse Ventricular-Subventricular Zone

Neurogenesis and gliogenesis continue in the Ventricular-Subventricular Zone (V-SVZ) of the adult rodent brain. B1 cells are astroglial cells derived from radial glia that function as primary progenitors or neural stem cells (NSCs) in the V-SVZ. B1 cells, which have a small apical contact with the ventricle, decline in numbers during early postnatal life, yet neurogenesis continues into adulthood. Here we found that a second population of V-SVZ astroglial cells (B2 cells), that do not contact the ventricle, function as NSCs in the adult brain. B2 cell numbers increase postnatally, remain constant in 12-month-old mice and decrease by 18 months. Transcriptomic analysis of ventricular-contacting and non-contacting B cells revealed key molecular differences to distinguish B1 from B2 cells. Transplantation and lineage tracing of B2 cells demonstrate their function as primary progenitors for adult neurogenesis. This study reveals how NSC function is relayed from B1 to B2 progenitors to maintain adult neurogenesis.

neuroscience↗

bioRxiv2024

Neuronal migration depends on blood flow in the adult brain

In animal tissues, several cell types migrate along blood vessels, raising the possibility that blood flow influences cell migration. Here, we show that blood flow promotes the migration of new olfactory-bulb neurons in the adult brain. Neuronal migration is facilitated by blood flow, leading to accumulation of new neurons near blood vessels with abundant blood flow. Blood flow inhibition attenuates blood vessel-guided neuronal migration, suggesting that blood contains factors beneficial to neuronal migration. We found that ghrelin, which is increased in blood by hunger, directly influences neuronal migration. Ghrelin signaling promotes somal translocation by activating actin cytoskeleton contraction at the rear of the cell soma. New neurons mature in the olfactory bulb and contribute to the olfactory function for sensing odorants from food. Finally, we show that neuronal migration is increased by calorie restriction, and that ghrelin signaling is involved in the process. This study suggests that blood flow promotes neuronal migration through blood-derived ghrelin signaling in the adult brain, which could be one of the mechanisms that improves the olfactory function for food-seeking behavior during starvation.

neuroscience↗

bioRxiv2023

Intratumoral injection of melatonin enhances tumor regression in cell line-derived and patient-derived xenografts of head and neck cancer by increasing mitochondrial oxidative stress

Head and neck squamous cell carcinoma present a high mortality rate. Melatonin has been shown to have oncostatic effects in different types of cancers. However, inconsistent results have been reported for in vivo applications. Consequently, an alternative administration route is needed to improve bioavailability and establish the optimal dosage of melatonin for cancer treatment. On the other hand, the use of patient-derived tumor models has transformed the field of drug research because they reflect the heterogeneity of patient tumor tissues. In the present study, we explore mechanisms for increasing melatonin bioavailability in tumors and investigate its potential as an adjuvant to improve the therapeutic efficacy of cisplatin in the setting of both xenotransplanted cell lines and primary human HNSCC. We analyzed the effect of two different formulations of melatonin administered subcutaneously or intratumorally in Cal-27 and SCC-9 xenografts and in patient-derived xenografts. Melatonin effects on tumor mitochondrial metabolism was also evaluated as well as melatonin actions on tumor cell migration. In contrast to the results obtained with the subcutaneous melatonin, intratumoral injection of melatonin drastically inhibited tumor progression in HNSCC-derived xenografts, as well as in patient-derived xenografts. Interestingly, intratumoral injection of melatonin potentiated CDDP effects, decreasing Cal-27 tumor growth. We demonstrated that melatonin increases ROS production and apoptosis in tumors, targeting mitochondria. Melatonin also reduces migration capacities and metastasis markers. These results illustrate the great clinical potential of intratumoral melatonin treatment and encourage a future clinical trial in cancer patients to establish a proper clinical melatonin treatment.

cancer biology↗

bioRxiv2022

A cross-species proteomic map of synapse development reveals neoteny during human postsynaptic density maturation

The molecular mechanisms and evolutionary changes accompanying synapse development are still poorly understood. Here, we generated a cross-species proteomic map of synapse development in the human, macaque, and mouse neocortex. By tracking the changes of >1,000 postsynaptic density (PSD) proteins from midgestation to young adulthood, we found that PSD maturation in humans separates into three major phases that are dominated by distinct pathways. Cross-species comparisons reveal that the human PSD matures about two to three times slower than other species and contains higher levels of Rho guanine nucleotide exchange factors (RhoGEFs) in the perinatal period. Enhancement of the RhoGEF signaling in human neurons delays the morphological maturation of dendritic spines and the functional maturation of synapses, potentially contributing to the neotenic traits of human brain development. In addition, PSD proteins can be divided into four modules that exert stage- and cell type-specific functions, possibly explaining their differential associations with cognitive functions and diseases. Together, our proteomic map of synapse development provides a blueprint for studying the molecular basis and evolutionary changes of synapse maturation.

neuroscience↗

bioRxiv2022

Persistent postnatal migration of interneurons into the human entorhinal cortex

The entorhinal cortex (EC) is a highly-interconnected hub for multisensory integration and memory processing1-3, containing diverse neuronal subtypes4,5 including subpopulations that are uniquely spatially-tuned6,7. Although many spatial and memory functions develop in infancy, it is considered that neurogenesis and neuronal migration to the EC occurs prenatally. Here we show that the postnatal human temporal lobe contains a prominent stream with large chains of young migrating neurons and many individual neurons breaking away directed into the EC. The EC stream forms between the second and third trimesters of prenatal development when the lateral ventricle walls in the temporal lobe collapse, displacing the subventricular zone (SVZ) and dividing radial glia. At birth, the EC stream follows a path of radial glial [fi]bers in the site of the collapsed ventricle. Migratory chains persist up to 11 months postnatally; however, many individually migrating young neurons can still be detected in the EC at 2 years of age and a few isolated cells at 3 years of age. Within the EC at birth, immature neurons are a mixed population expressing markers of the medial ganglionic eminence (MGE) and caudal ganglionic eminence (CGE), but postnatally rapidly become primarily CGE-derived. Using single-nuclei RNAseq we identified these lineages and found that the MGE-derived neurons matured at earlier postnatal ages compared to those derived from the CGE. The CGE interneurons arriving and maturing the latest included subtypes expressing calretinin (CR), reelin (RELN), and vasoactive intestinal protein (VIP) many of which settle in layer II of the entorhinal cortex. This study reveals that the human EC is still being constructed during the first years of life revealing the largest known postnatal stream of migratory neurons in humans. The protracted postnatal arrival of a diverse population of interneurons could contribute to plasticity8,9 and proper excitation-inhibition balance10,11 within these highly connected brain circuits.

neuroscience↗

bioRxiv2022

Regulation of adult neurogenesis and neuronal differentiation by Neural Cell Adhesion Molecule 2 (NCAM2)

Adult neurogenesis persists in mammals in the neurogenic zones where newborn neurons are incorporated into existing neuronal circuits. Relevant molecular elements of the neurogenic niches include the family of Cell Adhesion Molecules (CAM), which participate in signal transduction and regulate radial glial progenitors (RGPs) survival, division and differentiation. The Neural Cell Adhesion Molecule 2 (NCAM2) is expressed in brain development and in adult stages, and controls dendrite arborisation and synaptic formation and maintenance during development. Nevertheless, the role of NCAM2 in neurogenesis and lineage progression is not well understood. Here we analyse the functions of NCAM2 in the regulation of RGPs in adult neurogenesis in the dentate gyrus and during corticogenesis, by using different lentiviral-mediated genetic approaches to modulate its expression, both in vivo and in vitro. First, we characterized the expression of NCAM2 among the main actors of the neurogenic process revealing different levels of NCAM2 amid the progression of RGPs and the formation of juvenile neurons. Further, we show that overexpression of NCAM2 arrest infected cells in a RGP-like state, with characteristic morphological, immunocytochemical and electron microscopy features. In contrast, NCAM2 overexpression in embryonic cortical progenitors does not seems to alter cell fate, but causes transient migration deficits. These results reveal a differential role of NCAM2 in the regulation of adult and embryonic RGPs, and specifically, a significant implication of NCAM2 in the regulation and progression of RGPs during adult neurogenesis in the hippocampus.

neuroscience↗

bioRxiv2021

Small Extracellular Vesicles Secreted by Region-specific Astrocytes Ameliorate the Mitochondrial Function in a Cellular Model of Parkinson's Disease

Extracellular vesicles (EVs) are emerging as powerful players in cell-to-cell communication both in health and diseased brain. In Parkinsons disease (PD) - characterized by selective dopaminergic (DAergic) neuron death in ventral midbrain (VMB) and degeneration of DAergic terminals in striatum (STR) - astrocytes (AS) exert dual harmful/protective functions. When activated by chemokine CCL3, AS promote a robust DAergic neuroprotection both in cellular and pre-clinical models of PD, with mechanisms not fully elucidated. Here we used a combination of techniques to characterize AS-EVs derived from VMB and STR, and investigated their potential to exert neuroprotection. First, we show that: (i) AS of both regions secrete small EVs of ~100 nm; (ii) VMB-AS release more EVs per cell than STR-AS under basal conditions; and (iii) only VMB-AS respond to CCL3 by producing more EVs, suggesting differential AS-EV secretion rate according to PD brain region. Next, addressing AS-EV potential against oxidative stress and mitochondrial toxicity, we found that AS-EVs, especially CCL3-AS-EVs, fully counteract H2O2-induced caspase-3 activation. Furthermore, using high resolution respirometry, we demonstrated that AS-EVs rescue the neuronal mitochondrial complex I function impaired by MPP+, with VMB-AS-EVs fully restoring ATP production in MPP+-injured neurons, highlighting a regional diversity of AS-EVs with neuroprotective implications for PD.

neuroscience↗

bioRxiv2021

A ciliopathy complex builds distal appendages to initiate ciliogenesis

Cells inherit two centrioles, the older of which is uniquely capable of generating a cilium. Using proteomics and super-resolved imaging, we identified a module which we term DISCO (DIStal centriole COmplex). DISCO components CEP90, MNR and OFD1 underlie human ciliopathies. This complex localized to both distal centrioles and centriolar satellites, proteinaceous granules surrounding centrioles. Cells and mice lacking CEP90 or MNR did not generate cilia, failed to assemble distal appendages, and did not transduce Hedgehog signals. Disrupting the satellite pools did not affect distal appendage assembly, indicating that it is the centriolar populations of MNR and CEP90 that are critical for ciliogenesis. CEP90 recruited the most proximal known distal appendage component, CEP83, to root distal appendages formation, an early step in ciliogenesis. In addition, MNR, but not CEP90, restricted centriolar length by recruiting OFD1. We conclude that DISCO acts at the distal centriole to support ciliogenesis by restraining centriole length and assembling distal appendages, defects in which cause human ciliopathies. eTOC summaryKumar et al. identifies a multi-protein complex called DISCO (DIStal centriole COmplex) required to nucleate distal appendages and restrain centriole elongation, essential for the initiation of cilium assembly. Without DISCO, cells fail to ciliate and transduce Hedgehog signals, critical for mammalian development.

cell biology↗

bioRxiv2020

Enhanced tissue penetration of antibodies through pressurized immunohistochemistry

To address the inefficiency of passive diffusion for antibody penetration in thick tissue samples, which limits clearing-technique applications, we developed a versatile and simple device to perform antibody incubation under increased barometric pressure. Pressurized immunohistochemistry greatly improves the uniformity, intensity, and depth of fluorescent immunostaining in thick human and mouse brain samples. Furthermore, pressurized immunohistochemistry substantially decreases the time required for classic staining of thin sections. SUBMISSION CATEGORYNew Results

molecular biology↗