Biology subjects

Russo, A.

Publications and source records attributed to Russo, A..

18 recordsLinked to original sources

bioRxiv2026

Activity-based profiling of primary brain cells identifies covalent allosteric modulators of HCN channels

Chemical proteomics can provide global portraits of small molecule-protein interactions in native biological systems. Such ligandability maps have, however, been mostly restricted to readily accessible cell lines and primary immune cells. Here, we describe an activity-based protein profiling (ABPP) strategy for mapping the covalent ligandability of primary brain cells isolated from mice. By investigating sets of stereochemically defined electrophilic small molecules (stereoprobes), we identify liganding events for diverse brain cell proteins, including many with nervous system-enriched expression. In this category were multiple hyperpolarization-activated cyclic nucleotide-gated (HCN) ion channels, which we show are covalently liganded by tryptoline acrylamide stereoprobes at a conserved cysteine in their cyclic nucleotide-binding domain. The stereoprobes were found to block cAMP-dependent shifts in voltage dependence while sparing basal activity of HCN channels. We thus describe an advanced ABPP platform for identifying ligands targeting nervous system-enriched proteins, including chemical probes that modulate HCN channel function in cells.

biochemistry↗

bioRxiv2026

Glymphatic function restored by α1-noradrenergic antagonism alleviates headache allodynia in mice

Mild traumatic brain injury (mTBI) often leads to migraine-like post-traumatic headache (PTH), yet effective treatments are limited. Clinical and preclinical studies have shown that mTBI disrupts glymphatic transport of cerebrospinal fluid in the brain. We hypothesized that altered glymphatic transport might underlie facial allodynia commonly associated with migraine and PTH. A closed-head impact model was used to induce mTBI in mice. Facial allodynia, a symptom of PTH and migraine, was evaluated using periorbital von Frey testing. Glymphatic influx was assessed using slice-based imaging of a fluorescent tracer injected into the cisterna magna. Here we show that prazosin (PZN), an 1-noradrenergic receptor antagonist, restores glymphatic function and treats facial allodynia induced by calcitonin gene-related peptide (CGRP) and a nitric oxide donor in mice. In contrast, propranolol, a {beta}-noradrenergic receptor antagonist, was ineffective. Even in the absence of mTBI, CGRP reduced glymphatic function and PZN was able to restore glymphatic function in the dorsal cortex. Importantly, the role of glymphatic function was confirmed by the lack of PZN efficacy in aquaporin-4 knockout mice. These findings indicate that targeting 1-noradrenergic receptors to enhance glymphatic transport may offer a therapeutic strategy for treating migraine and PTH.

neuroscience↗

bioRxiv2026

Iota-carrageenan protects the ocular surface from desiccation-induced cell death and tissue damage in vitro and ex vivo

Iota-carrageenan is a natural polymer with moisturizing, mucoadhesive and shear-thinning properties. In this study, we aimed to evaluate the protective effects of iota-carrageenan on ocular surface against dehydration, to demonstrate its suitability for the use in lubricant eye drops. We utilized a human epithelial corneal cell culture model to test if pre-incubation with iota-carrageenan solution could protect cells from desiccation-induced cell death, to compare its effect with other natural polymers commonly used in artificial tear products, and to determine the optimal iota-carrageenan concentration. An ex vivo porcine eye model was established to confirm the protective effect of iota-carrageenan against dehydration on ocular tissue. Pre-incubation with 1.2 mg/ml iota-carrageenan increased the survival half-life of human corneal epithelial cells upon dehydration by three-fold; the effect was in the same range as observed for large molecular weight hyaluronic acid, and superior to all other tested natural polymers. The highest tested concentration of iota- carrageenan, 1.6 mg/ml, extended the cellular survival half-life by eight-fold while maintaining healthy cellular morphology. Repeated ex vivo instillation of an iota-carrageenan-based ophthalmic formulation into porcine eyes significantly protected the ocular surface from desiccation-induced corneal damage, as shown by corneal fluorescein staining These data suggest that Iota-carrageenan effectively moisturizes and protects the ocular surface, supporting its potential as a promising novel ingredient for eye drops in the management of dry eye disease.

physiology↗

bioRxiv2025

Endothelial Type I Interferon signaling modulates the vascular response to ischemic brain injury

Vascular normalization [stabilization of aberrant angiogenesis and restoration of blood-brain barrier (BBB)] is critical for reducing long-term secondary sequelae after ischemic stroke. How immune and developmental signaling pathways coordinate these processes is poorly understood. Here we identify a unique brain endothelial cell (BEC) type one interferon (IFN1) signature in human and mouse ischemic stroke tissue. By leveraging two clinically-relevant murine ischemic stroke models, single-cell transcriptomics, and BBB functional assays, we find that deletion of endothelial IFN1 receptor (Ifnar1) exacerbates post-stroke BBB disruption and expands a BEC population expressing angiogenic and immature BBB markers. Conversely, IFN{beta} administration after stroke reduces acute BBB disruption. Activation of IFN1 signaling in BECs in vitro reduces vascular endothelial growth factor (VEGF) signaling to promote junctional stabilization, enhance barrier properties, and suppress angiogenic features. Thus, endogenous endothelial IFN1 signaling modulates BBB dysfunction and angiogenesis to promote vascular normalization after ischemic brain injury.

neuroscience↗

bioRxiv2025

Inflamed Microglia like Macrophages in the Central Nervous System of Prodromal Parkinson's Disease

We hypothesized that prodromal Parkinsons Disease (PD), characterized by REM Sleep Behavior Disorder and hyposmia, is an inflammatory disorder initiated in the gut that evolves into a neurodegenerative process manifest as classical PD. To test this hypothesis, we performed single-cell RNAseq analysis of cerebrospinal fluid (CSF) and blood from 118 individuals, comparing healthy subjects with prodromal PD and manifest PD to patients with the central nervous system (CNS) autoimmune disease, multiple sclerosis (MS). Surprisingly, we identified increased numbers of immune cells in the CSF of patients with prodromal PD. Single-cell RNA sequencing revealed increases in CSF-specific microglia-like macrophages with enhanced JAK-STAT and TNF signaling signatures in prodromal PD. CSF macrophages exhibited similar transcriptional profiles to dural macrophages and gut muscularis macrophages from -synuclein-expressing PD model mice. Finally, shared memory T cell clones were found in humans between gut and CSF T cells. These findings uncover a myeloid-mediated TNF inflammatory process in the CNS of patients with prodromal PD, with an immunological linkage between the gut and the CNS.

immunology↗

bioRxiv2025

Inhibition of Posterior Thalamic Nuclei Attenuates CGRP-induced Migraine-like Behavior in Mice

ObjectiveTo determine whether induction of migraine-like symptoms in mice by calcitonin gene-related peptide (CGRP) requires activation of the posterior thalamic nuclei (PoT) in the brain.BackgroundPrevious research found that both optical activation of the PoT and injection of CGRP into the PoT are sufficient to induce light aversive behavior in mice. The PoT is well known as a sensory integration center of light and pain signals in the brain. However, whether this region is required for touch hypersensitivity and light aversion following peripheral administration of CGRP was not known.MethodsThe PoT was injected in two strains of mice, inbred C57BL/6J and outbred CD-1, with viral vectors expressing inhibitory chemogenetic Designer Receptors Exclusively Activated by Designer Drugs (DREADDs). The inhibitory DREADDs were activated by systemic intraperitoneal (ip) injection of two designer drugs, clozapine N-oxide (CNO) and DREADD agonist compound 21 (C21). We used ip injection of CGRP to induce migraine-like phenotypes and tested whether we could rescue these phenotypes by bilateral chemogenetic inhibition of the PoT. The light/dark assay was used to measure light aversive behavior (a surrogate for photophobia) and the plantar von Frey assay to measure hindpaw touch sensitivity (a surrogate for extracephalic allodynia).ResultsWe successfully induced light aversive and hindpaw touch hypersensitivity phenotypes in mice using ip injections of CGRP. Activation of the inhibitory DREADDs in the PoT using ip CNO (5 mg/kg) was sufficient to partially rescue the touch hypersensitivity phenotype, but with off target effects in the control mice. Lowering the CNO dose to 1 mg/kg alleviated off target effects but was insufficient to rescue the touch hypersensitivity phenotype. On the other hand, C21 (1 mg/kg) fully rescued the touch hypersensitivity phenotype without any off target effects. Treatment with C21 also partially rescued the light aversion phenotype. These results were consistent across both C57BL/6J and CD-1 mouse strains.ConclusionInhibition of the PoT fully rescues CGRP-induced touch hypersensitivity and partially rescues light aversion in mice, indicating that the PoT is necessary for touch hypersensitivity and partially necessary for light aversive behaviors. These data suggest the PoT is part of a central network that receives peripheral CGRP-induced signals and thus could be harnessed for future targeted therapeutics for migraine.Plain language summaryThe posterior thalamus is a central brain region that contributes to migraine pathophysiology when stimulated. In this study, we asked if inhibition of this brain region could alleviate migraine-like phenotypes in mice. We found that inhibition of the posterior thalamus fully rescues touch hypersensitivity and partially rescues light aversive behavior, suggesting that the posterior thalamus is necessary for migraine pathophysiology and could offer a potential therapeutic target for migraine.

neuroscience↗

bioRxiv2024

A synthetic potassium channel reduces oxidative stress 1 via cellular adaptronics

Aerobic metabolism is crucial for human life but reactive oxygen species (ROS) byproducts cause cellular toxicity. Although antioxidant defenses usually maintain ROS levels within a safe range, ROS production can exceed the buffering capacity of cells, causing oxidative stress and disease. Inspired by the principle of adaptronics, we created a synthetic potassium channel that senses cellular ROS levels and mitigates oxidative stress by modulating membrane potential. Engineered from TASK1 channel, ROSTASK1 is sensitive to supraphysiological ROS levels, imposing restorative membrane potential changes on cells or organelles under oxidative stress. We also engineered a blue-light sensitive ROSTASK1 to achieve optogenetic control. In proof-of-concept experiments, mitochondrially-delivered ROSTASK1 rescued ROS overproduction in myoblasts from a Leigh syndrome patient and ROSTASK1 abolished chronic pain-like behavior in mouse models of inflammation and nerve injury. Thus, by functioning as both a sensor and modulator of ROS levels, ROSTASK1 provides a self-healing system during oxidative stress.

biophysics↗

bioRxiv2022

CGRP Administration into the Cerebellum Evokes Migraine-like Behaviors Predominately in Female Mice

The neuropeptide calcitonin gene-related peptide (CGRP) is a major player in migraine pathophysiology. Previous preclinical studies demonstrated that intracerebroventricular administration of CGRP caused migraine-like behaviors in mice, but the sites of action in the brain remain unidentified. The cerebellum has the most CGRP binding sites in the central nervous system and is increasingly recognized as both a sensory and motor integration center. The objective of this study was to test whether the cerebellum, particularly the medial cerebellar nuclei (MN), might be a site of CGRP action. In this study, CGRP was directly injected into the right MN of C57BL/6J mice via a cannula. A battery of behavioral tests was done to assess migraine-like behaviors. CGRP caused light aversion measured as decreased time in the light zone even with dim light. The mice also spent more time resting in the dark zone, but not the light, along with decreased rearing and transitions between zones. These behaviors were similar for both sexes. In contrast, significant responses to CGRP were seen only with female mice in the open field assay, von Frey test, and automated squint assay, indicating anxiety, tactile hypersensitivity, and spontaneous pain, respectively. In male mice, the responses had the same trend as females but did not reach statistical significance. No detectable effect of CGRP on gait was observed in either sex. These results suggest that CGRP in the MN causes light aversion in males, while in females, light aversion is accompanied by increased anxiety, tactile hypersensitivity, and spontaneous pain. A caveat is that we cannot exclude contributions from other cerebellar regions in addition to the MN due to diffusion of the injected peptide. These results reveal the cerebellum as a new site of CGRP actions that may contribute to migraine pathophysiology and possibly its prevalence in females.

neuroscience↗

bioRxiv2022

The voltage-gated Cav Ca2+ channel subunit α2δ-4 is required for locomotor behavior and sensorimotor gating in mice

Voltage-gated Cav Ca2+ channels are critical for the development and mature function of the nervous system. Variants in the CACNA2D4 gene encoding the 2{delta}-4 auxiliary subunit of these channels are associated with neuropsychiatric and neurodevelopmental disorders. 2{delta}-4 is prominently expressed in the retina and is crucial for vision, but extra-retinal functions of 2{delta}-4 have not been investigated. Here, we sought to fill this gap by analyzing the behavioral phenotypes of 2{delta}-4 knockout (KO) mice. 2{delta}-4 KO mice (both males and females) exhibited significant impairments in prepulse inhibition that were unlikely to result from the modestly elevated auditory brainstem response thresholds. Whereas 2{delta}-4 KO mice of both sexes were hyperactive in various assays, only females showed impaired motor learning/coordination in the rotarod assay. Female but not male 2{delta}-4 KO mice exhibited anxiolytic and anti-depressive behaviors in the elevated plus maze and tail suspension tests, respectively. Our results reveal an unexpected role for 2{delta}-4 in cognitive and motor function and identify 2{delta}-4 KO mice as a novel model for studying the pathophysiology associated with CACNA2D4 variants.

neuroscience↗

bioRxiv2021

A phenotypic rescue approach identifies lineage regionalization defects in a mouse model of DiGeorge syndrome.

TBX1 is a key regulator of pharyngeal apparatus (PhAp) development. Vitamin B12 treatment partially rescues aortic arch patterning defects of Tbx1+/- embryos. Here we show that it also improves cardiac outflow tract septation and branchiomeric muscle anomalies of Tbx1 hypomorphic mutants. At molecular level, the in vivo vB12 treatment let us to identify genes that were dysregulated by Tbx1 haploinsufficiency and rescued by treatment. We found that SLUG, encoded by the rescued gene Snai2, identified a population of mesodermal cells that was partially overlapping with but distinct from ISL1+ and TBX1+ populations. In addition, SLUG+ cells were mislocalized and had a greater tendency to aggregate in Tbx1+/- and Tbx1-/- embryos and vB12 treatment restore cellular distribution. Adjacent neural crest-derived mesenchymal cells, which do not express TBX1, were also affected, showing enhanced segregation from cardiopharyngeal mesodermal cells. We propose that TBX1 regulates cell distribution in core mesoderm and the arrangement of multiple lineages within the PhAp.

developmental biology↗

bioRxiv2021

2.5D Tractions in monocytes reveal mesoscale mechanics of podosomes during substrate indenting cell protrusion

Degradation and protrusion are key to cellular barrier breaching in cancer metastasis and leukocyte extravasation. Cancerous invadopodia and myelomonocytic podosomes are widely considered as structural tools facilitating these processes and are thus summarized under the term invadosomes. Despite similar behaviour on the individual scale, substantial differences have been reported to arise on the collective scale. They are considered to be a result of podosome mesoscale-connectivity. In this study, we investigated global in-plane and out-of-plane mechanical forces of podosome clusters in ER-Hoxb8 cell derived monocytes. We are able to correlate these forces with the interpodosomal connectivity. The observed traction and protrusion patterns fail to be explained by summation of single podosome mechanics. Instead, they appear to originate from superimposed mesoscale effects. Based on mechanistic and morphological similarities with epithelial monolayer mechanics, we propose a spatiotemporal model of podosome cluster mechanics capable of relating single to collective podosome mechanical behaviour. Our results suggest that network contraction-driven (in-plane) tractions lead to a buckling instability that contributes to the out-of-plane indentation into the substrate. First assigning an active mechanical role to the dorsal podosome actomyosin network, we aim at translating actomyosin hierarchy into scale dependency of podosome mechanics.

biophysics↗

bioRxiv2021

Motor cortex activity across movement speeds is predicted by network-level strategies for generating muscle activity

Learned movements can be skillfully performed at different paces. What neural strategies produce this flexibility? Can they be predicted and understood by network modeling? We trained monkeys to perform a cycling task at different speeds, and trained artificial recurrent networks to generate the empirical muscle-activity patterns. Network solutions reflected the principle that smooth well-behaved dynamics require low trajectory tangling. Network solutions had a consistent form, which yielded quantitative and qualitative predictions. To evaluate predictions, we analyzed motor cortex activity recorded during the same task. Responses supported the hypothesis that the dominant neural signals reflect not muscle activity, but network-level strategies for generating muscle activity. Single-neuron responses were better accounted for by network activity than by muscle activity. Similarly, neural population trajectories shared their organization not with muscle trajectories, but with network solutions. Thus, cortical activity could be understood based on the need to generate muscle activity via dynamics that allow smooth, robust control over movement speed.

neuroscience↗

bioRxiv2020

Endothelial cell invasiveness is controlled by myosin IIA-dependent inhibition of Arp2/3 activity

Sprouting angiogenesis is fundamental for development and contributes to multiple diseases, including cancer, diabetic retinopathy and cardiovascular diseases. Sprouting angiogenesis depends on the invasive properties of endothelial tip cells. However, there is very limited knowledge on the mechanisms that endothelial tip cells use to invade into tissues. Here, we prove that endothelial tip cells use long lamellipodia projections (LLPs) as the main cellular protrusion for invasion into non-vascular extracellular matrix. We show that LLPs and filopodia protrusions are balanced by myosin-IIA (MIIA) and actin-related protein 2/3 (Arp2/3) activity. Endothelial cell-autonomous ablation of MIIA promotes excessive LLPs formation in detriment of filopodia. Conversely, endothelial cell-autonomous ablation of Arp2/3 prevents LLPs development and leads to excessive filopodia formation. We further show that MIIA inhibits Rac1-dependent activation of Arp2/3, by regulating the maturation state of focal adhesions. Our discoveries establish the first comprehensive model of how endothelial tip cells regulate its protrusive activity and will pave the way towards new strategies to block invasive tip cells during sprouting angiogenesis.

cell biology↗

bioRxiv2020

Increased likelihood of heat-induced large wildfires in the Mediterranean Basin

Wildfire activity is expected to increase across the Mediterranean Basin because of climate change. However, the effects of future climate changes on the combinations of atmospheric conditions that promote large wildfires remain largely unknown. Using a fire-weather based classification of wildfires, we show that future climate scenarios point to an increase in the frequency and severity of two heat-induced fire-weather types that have been responsible for a majority of record-breaking wildfire events. Heat-induced fire-weather types are characterized by compound dry warm conditions and occur in the summer during heatwaves, either under moderate (sudden heatwave type) or intense (hot drought type) drought. Heat-induced fire weather is projected to increase in frequency by 14% by the end of the century (2071-2100) under the RCP4.5 scenario, and by 30% under the RCP8.5. These findings suggest that the frequency and extent of large wildfires will increase throughout the Mediterranean Basin, with far-reaching impacts.

ecology↗

bioRxiv2019

Neural trajectories in the supplementary motor area and primary motor cortex exhibit distinct geometries, compatible with different classes of computation

The supplementary motor area (SMA) is believed to contribute to higher-order aspects of motor control. To examine this contribution, we employed a novel cycling task and leveraged an emerging strategy: testing whether population trajectories possess properties necessary for a hypothesized class of computations. We found that, at the single-neuron level, SMA exhibited multiple response features absent in M1. We hypothesized that these diverse features might contribute, at the population level, to avoidance of population trajectory divergence - ensuring that two trajectories never followed the same path before separating. Trajectory divergence was indeed avoided in SMA but not in M1. Network simulations confirmed that low trajectory divergence is necessary when guidance of future action depends upon internally tracking contextual factors. Furthermore, the empirical trajectory geometry - helical in SMA versus elliptical in M1 - was naturally reproduced by networks that did, versus did not, internally track context.

neuroscience↗

bioRxiv2019

Transient upregulation of translational efficiency in prodromal Tg2576 mice precipitates AD symptoms

Tg2576 mice overexpressing APPK670/671L exhibit elevated hAPP levels from birth but remain at a prodromal stage until 3 months of age. Whether variations in hAPP mRNA specific and overall translation occur during development and precipitates the transition from an asymptomatic to a symptomatic stage is unknown. By performing polysome profiling and distribution of hAPP, and measuring the levels of eukaryotic initial translation factors in hippocampal extracts from pre- and early symptomatic Tg2576 mice, we found that the presence of mRNA and protein polysomal signals was associated with decreased levels of the phosphorylated form of the initial translation factor eIF2 (p-eIF2), revealing a transient upregulation of overall translation. Differently, the reduction of hAPP mRNA polysomal signals was associated with increased p-eIF2 levels - repressing translation-when mice were symptomatic, suggesting a compensatory mechanism aimed at downregulating hAPP mRNA. Confirming that prodromal upregulation of translational efficiency contributes to AD pathogenesis, pharmacological restoration of proper translational control in early symptomatic mice blocked the manifestation of neural and cognitive AD-like alterations.

neuroscience↗

bioRxiv2018

Stochastic rank aggregation for the identification of functional neuromarkers

Background and aimsThe main challenge in analysing functional magnetic resonance imaging (fMRI) data from extended samples of subject (N>100) is to extract as much relevant information as possible from big amounts of noisy data. When studying neurodegenerative diseases with resting-state fMRI, one of the objectives is to determine regions with abnormal background activity with respect to a healthy brain and this is often attained with comparative statistical models applied to single voxels or brain parcels within one or several functional networks. In this work, we propose a novel approach based on clustering and stochastic rank aggregation to identify parcels that exhibit a coherent behaviour in groups of subjects affected by the same disorder and apply it to default-mode network independent component maps from resting-state fMRI data sets.\n\nMethodsBrain voxels are partitioned into parcels through k-means clustering, then solutions are enhanced by means of consensus techniques. For each subject, clusters are ranked according to their median value and a stochastic rank aggregation method, TopKLists, is applied to combine the individual rankings within each class of subjects. For comparison, the same approach was tested on an anatomical parcellation.\n\nResultsWe found parcels for which the rankings were different among control subjects and subjects affected by Parkinsons disease and amyotrophic lateral sclerosis and found evidence in literature for the relevance of top ranked regions in default-mode brain activity.\n\nConclusionsThe proposed framework represents a valid method for the identification of functional neuromarkers from resting-state fMRI data, and it might therefore constitute a step forward in the development of fully automated data-driven techniques to support early diagnoses of neurodegenerative diseases.

neuroscience↗

bioRxiv2017

The Drosophila Eukaryotic Initiation Factor eIF6 affects development by regulating apoptosis via the ecdysone pathway

During development, ribosome biogenesis and translation reach peak activities, due to impetuous cell proliferation. Current models predict that protein synthesis elevation is controlled by transcription factors and signalling pathways. Developmental models addressing translation factors overexpression effects are lacking. Eukaryotic Initiation Factor (eIF6) is necessary for ribosome biogenesis and efficient translation. eIF6 is a single gene, conserved from yeasts to mammals, suggesting a tight regulation need. We generated a Drosophila melanogaster in vivo model of eIF6 upregulation, demonstrating a boost in general translation and the shut off of the ecdysone biosynthetic pathway. Translation modulation in S2 cells showed that translational rate and ecdysone biosynthesis are inversely correlated. In vivo, eIF6-driven alterations delayed programmed cell death (PCD), resulting in aberrant phenotypes, partially rescued by ecdysone administration. Our data show that eIF6 triggers a translation program with far-reaching effects on metabolism and development, stressing the driving and central role of translation.

developmental biology↗