Biology subjects

Gonsalves, N.

Publications and source records attributed to Gonsalves, N..

5 recordsLinked to original sources

bioRxiv2025

A 3D Human Neuron-on-Chip Platform to Monitor Neuronal Injury Responses

Traumatic brain injury (TBI) is a major cause of neurological dysfunction and long-term neurodegeneration, yet the intrinsic neuronal contributions to TBI pathophysiology remain incompletely defined. Here, we present a novel Neuron-on-Chip microfluidic platform that can be used to mechanically injure mature human prefrontal cortex neurons (hPFCs) embedded in three-dimensional (3D) hydrogels, enabling the study of injury responses in pure neuronal cultures. We assessed real-time calcium dynamics across 13 metrics of single-cell and network activity, revealing a biphasic injury response: an early phase (0.5-24 hr) characterized by excitotoxicity, hyper-synchronized bursting, and network collapse; and a late phase (8 d) marked by sustained depolarization and structural remodeling. Secretome profiling uncovered progressive elevations in extracellular pT181 and total Tau from days 1 to 5 post-injury. Cytokine analyses identified early (24 hr) elevations in IP-10, IL-10, IFN2, and NCAM, and late increases (8 d) in CXCL9 and MPO, linking neuronal activity changes to stage-specific inflammatory signaling. Immunocytochemistry and immunoblotting confirmed temporally ordered upregulation of calpain-1 and active caspase-3 (days 1-3), phosphorylated Tau (AT8+, days 5-8), and neurofibrillary tangle-like Tau aggregates (NFT+, day 8). These findings establish our platform as a scalable microphysiological model for probing the dynamic cellular and molecular sequelae of neuronal response to injury, offering insights into neurodegeneration and opportunities for therapeutic discovery.

neuroscience↗

bioRxiv2025

Disrupting Akt-Wnt/β-catenin signaling suppresses glioblastoma stem cell growth and tumor progression in immunocompetent mice

Glioblastoma (GBM) is an aggressive primary malignant brain tumor in adults with a median patient survival of 12-18 months post-diagnosis. The PI3K/Akt and Wnt/{beta}-catenin signaling pathways promote GBM cell growth, survival, invasiveness and therapeutic resistance. We hypothesize that inhibiting Akt and {beta}-catenin, which are central regulatory proteins of the PI3K/Akt and Wnt/{beta}-catenin pathway, will suppress GBM growth and progression. Our in vitro studies demonstrate that MK-2206, a pan-Akt inhibitor, effectively reduced cell viability, induced apoptosis, and inhibited {beta}-catenin activity; consistently outperforming iCRT3, a {beta}-catenin-TCF interaction inhibitor, in CT-2A mouse glioma cells, and N08-30 human glioma stem cells. Luciferase-expressing CT-2A cells were then intracranially implanted in C57BL/6J mice followed by MK-2206 treatment, and we observed a reduction in phosphorylated Akt and GSK-3{beta} levels, consistent with disruption of the Akt and Wnt/{beta}-catenin signaling axis causing tumor suppression. In summary, MK-2206 outperformed iCRT3 efficacy in vitro, and suppressed GBM progression, in vivo. These findings suggest that Akt inhibition via MK-2206 may offer a promising therapeutic strategy for treating GBM characterized by dysregulation of PI3K/Akt or Wnt/{beta}-catenin pathways.

cancer biology↗

bioRxiv2024

Esophageal epithelial Ikkβ deletion promotes eosinophilic esophagitis in experimental allergy mouse model

BackgroundEosinophilic esophagitis (EoE) is a chronic T helper type 2 (Th2)-associated inflammatory disorder triggered by food allergens, resulting in esophageal dysfunction through edema, fibrosis, and tissue remodeling. The role of epithelial remodeling in EoE pathogenesis is critical but not fully understood. ObjectiveTo investigate the role of epithelial IKK{beta}/NF{kappa}B signaling in EoE pathogenesis using a mouse model with conditional Ikk{beta} knockout in esophageal epithelial cells (Ikk{beta}EEC-KO). MethodsEoE was induced in Ikk{beta}EEC-KOmice through skin sensitization with MC903/Ovalbumin (OVA) followed by intraesophageal OVA challenge. Histological and transcriptional analyses were performed to assess EoE features. Single-cell RNA sequencing (scRNA-seq) was used to profile esophageal mucosal cell populations and gene expression changes. ResultsIkk{beta}EEC-KO/EoE mice exhibited hallmark EoE features, including eosinophil infiltration, intraepithelial eosinophils, microabscesses, basal cell hyperplasia, and lamina propria remodeling. RNA-seq revealed significant alterations in IKK{beta}/NF{kappa}B signaling pathways, with decreased expression of RELA and increased expression of IKK{beta} negative regulators. scRNA- seq analyses identified disrupted epithelial differentiation and barrier integrity, alongside increased type 2 immune responses and peptidase activity. ConclusionOur study demonstrates that loss of epithelial IKK{beta} signaling exacerbates EoE pathogenesis, highlighting the critical role of this pathway in maintaining epithelial homeostasis and preventing allergic inflammation. The Ikk{beta}EEC-KO/EoE mouse model closely mirrors human EoE, providing a valuable tool for investigating disease mechanisms and therapeutic targets. This model can facilitate the development of strategies to prevent chronic inflammation and tissue remodeling in EoE. Key MessagesO_LICritical Role of Epithelial IKK{beta}/NF{kappa}B Signaling: Loss of this signaling exacerbates EoE, causing eosinophil infiltration, basal cell hyperplasia, and tissue remodeling, highlighting its importance in esophageal health. C_LIO_LIMolecular Insights and Therapeutic Targets: scRNA-seq identified disrupted epithelial differentiation, barrier integrity, and enhanced type 2 immune responses, suggesting potential therapeutic targets for EoE. C_LIO_LIRelevance of the Ikk{beta}EEC-KO/EoE Mouse Model: This model replicates human EoE features, making it a valuable tool for studying EoE mechanisms and testing treatments, which can drive the development of effective therapies. C_LI Capsule SummaryThis study reveals the crucial role of epithelial IKK{beta}/NF{kappa}B signaling in EoE, providing insights into disease mechanisms and potential therapeutic targets, highly relevant for advancing clinical management of EoE.

immunology↗

bioRxiv2023

Suprabasal cells retaining stem cell identity programs drive basal cell hyperplasia in eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is an esophageal immune-mediated disease characterized by eosinophilic inflammation and epithelial remodeling, including basal cell hyperplasia (BCH) and loss of differentiation. Although BCH correlates with disease severity and with persistent symptoms in patients in histological remission, the molecular processes driving BCH remain poorly defined. Here, we demonstrate that despite the presence of BCH in all EoE patients examined, no increase in basal cell proportion was observed by scRNA-seq. Instead, EoE patients exhibited a reduced pool of KRT15+ COL17A1+ quiescent cells, a modest increase in KI67+ dividing epibasal cells, a substantial increase in KRT13+ IVL+ suprabasal cells, and a loss of differentiated identity in superficial cells. Suprabasal and superficial cell populations demonstrated increased quiescent cell identity scoring in EoE with the enrichment of signaling pathways regulating pluripotency of stem cells. However, this was not paired with increased proliferation. Enrichment and trajectory analyses identified SOX2 and KLF5 as potential drivers of the increased quiescent identity and epithelial remodeling observed in EoE. Notably, these findings were not observed in GERD. Thus, our study demonstrates that BCH in EoE results from an expansion of non-proliferative cells that retain stem-like transcriptional programs while remaining committed to early differentiation.

molecular biology↗

bioRxiv2018

Increasing Rates of Diagnosis, Substantial Co-occurrence, and Variable Treatment Patterns of Eosinophilic Gastritis, Gastroenteritis and Colitis Based on 10 Year Data Across a Multi-Center Consortium

Financial Support and AcknowledgementsSupport for this project was provided through a research training grant as part of the Consortium of Eosinophilic Gastrointestinal Disease Researchers (CEGIR) (U54 AI117804). CEGIR is part of the Rare Disease Clinical Research Network (RDCRN), an initiative of the Office of Rare Diseases Research (ORDR), NCATS, and is funded through collaboration between NIAID, NIDDK, and NCATS. CEGIR is also supported by patient advocacy groups including APFED CURED and EFC. This project also received support from NIH T32 DK007634 (CCR).\n\nAuthor DisclosersPatricia Fulkerson: Grant funding from the NIH; Consultant for Genentech, Inc; Research support from Knopp Biosciences, LLC.\n\nGary Falk: Research support from Shire, Celgene, Adare, Regeneron. Consulting for Shire\n\nJonathan M. Spergel: Consultant for Regeneron, DBV Technology, Kaleo; Grant funding from DBV Technology, Aimmune Therapeutics, Food Allergy Research Education; Royalties from UpToDate\n\nNirmala Gonsalves: Royalties from UpToDate; Advisory board for Allakos\n\nSandeep K Gupta: Consultant for Alkalos, Abbott, QOL, Receptos; research support from Shire\n\nGlenn Furuta: Founder of EnteroTrack; Consultant for Shire; Royalties from UpToDate\n\nMarc E. Rothenberg: Consultant for Pulm One, Spoon Guru, ClostraBio, Celgene, Shire, Astra Zeneca, GlaxoSmithKline, Allakos, Adare, Regeneron and Novartis and has an equity interest in the first four listed and Immune Pharmaceuticals, and royalties from reslizumab (Teva Pharmaceuticals), PEESSv2 (Mapi Research Trust) and UpToDate. M.E.R. is an inventor of patents owned by Cincinnati Childrens.\n\nEvan Dellon: Consultant for Adare, Allakos, Alivio, Banner, Celgen/Receptos, Enumeral, GSK, Regeneron, Shire; Research funding from Adare, Celegene/Receptos, Miraca, Meritage, Nutricia, Regeneron, Shire, Educational grant from Banner, Holoclara\n\nStudy HighlightsO_ST_ABSWhat is current knowledge?C_ST_ABSO_LIEosinophilic gastrointestinal disorders (EGIDs) include eosinophilic esophagitis (EoE), eosinophilic gastritis (EG), gastroenteritis (EGE), and colitis (EC).\nC_LIO_LINon-EoE EGIDs are rare with most studies limited to case reports or review of single center experiences.\nC_LIO_LIThere are no widely established guidelines for the diagnosis of EG, EGE, or EC.\nC_LI\n\nWhat is new here?O_LIIn this multicenter study, EG, EGE, and EC were all diagnosed with increasing frequency over the past decade.\nC_LIO_LIPresenting symptoms are non-specific and do not reliably distinguish between disorders.\nC_LIO_LIThere was no male predominance and the majority of subjects had atopy.\nC_LIO_LICo-occurrence of EG, EGE, and EC diagnoses is common, seen in 41% of patients.\nC_LIO_LIThere is substantial variability between centers in initial treatment approaches.\nC_LI

epidemiology↗