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Gupta, K.

Publications and source records attributed to Gupta, K..

At least 19 recordsLinked to original sources

Evolutionarily Conserved Plasmodium falciparum HSP70-3 Enhances the Immunogenicity of the Established Malaria Vaccine Antigen Circumsporozoite Protein through Cross-Presentation

Background: Clinically approved P. falciparum circumsporozoite protein (PfCSP)-based pre-erythrocytic stage malaria vaccines suffer from sub-optimal efficacy and rapidly waning memory. By decoding these limitations, we fast-tracked vaccine optimization by correcting CSPs fragile immunogenicity using a parasite-derived chaperone. Unlike other orthologues of P. falciparum heat shock protein 70 (PfHSP70), substrate-binding domain (SBD) of PfHSP70-3 is an evolutionarily conserved internal mitochondrial matrix chaperone. We demonstrate that PfHSP70-3-SBD hydrophobic region complexes with PfCSP and targets host CD91 on antigen-presenting cells to trigger cross-presentation, resulting in enhanced immune responses to PfCSP. Methods: In silico analyses predicted interactions among PfHSP70-3-SBD, PfCSP, and CD91 receptor. Recombinant PfHSP70-3-SBD and PfCSP proteins were purified and assessed for in vitro interaction using ELISA and far-western dot blot assays. BALB/c mice were immunized with alum-formulated PfCSP, with or without PfHSP70-3-SBD. PfCSP-specific IgG and IFN-{gamma} expression were evaluated by ELISA and RT-qPCR, respectively. Functional activity was assessed using transgenic Plasmodium berghei expressing PfCSP (Pb/Pf CSP), by sporozoite neutralization assay. Findings: PfHSP70-3-SBD demonstrated a specific interaction with PfCSP. The complex primarily engages CD91 receptor cluster IV, providing a potential mechanistic basis for antigen cross-presentation. Incorporation of PfHSP70-3-SBD enhanced PfCSP-specific total IgG responses and increased IFN-gamma expression in BALB/c mice, indicating improved immunogenicity upon co-formulation. Notably, immune sera neutralized Pb/Pf CSP sporozoites, delaying blood-stage patency until day 12 in 40% of C57BL/6 mice, with no detectable parasitemia in surviving mice for up to 2 months, indicating sustained efficacy against the sporozoite stage. Interpretation: Molecular chaperones, including HSPs, are currently under intense investigation for their immune-potentiating activity, leading to next-generation vaccine development. By utilizing chaperonic domains derived directly from the pathogenic agent itself to serve an essential adjuvant function, this approach reduces reliance on heterologous adjuvants while enhancing antigen-specific immunity. Funding: This work was supported by funding from Indian Council of Medical Research (IIRPSG-2024-01-03940). Keywords: Substrate-binding domain, PfHSP70-3, Adjuvant, Cross-presentation, Pre-erythrocytic stage, Plasmodium falciparum

microbiology↗

Controlling membrane tension by dynamic DNA nanorings

Membrane tension, defined as the energy cost to expand the membrane surface area, is a fundamental mechanical property of the lipid bilayer and an important modulator of various cellular processes. Liposomes provide model systems to study protein-mediated membrane dynamics, where membrane tension can be controlled by osmotic pressure and micropipette aspiration. However, it is challenging to individually control membrane tension of nanometer-sized liposomes, such as small unilamellar vesicles (SUVs), that are widely used for modeling subcellular membrane structures and drug delivery. To bridge this technological gap, we present reconfigurable DNA origami rings for dynamically controlling membrane tension of sub-100 nm liposomes. The DNA nanorings template the formation of uniformly sized SUVs and undergo trigger-responsive dilation and contraction, thus applying controlled and reversible mechanical stress to the SUV membranes. Electron microscopy analyses show deformed liposomes with ~2.5% expanded membrane area following ring dilation. The corresponding increase in membrane tension opens a mechanosensitive ion channel MscL with gating tension of ~10 mN/m. Selectively manipulating a mixture of SUV populations enables timed release of their distinct molecular cargos, either concurrently or one at a time. Furthermore, vesicles with expanded membranes are more conducive to SNARE-mediated fusion. The nanomechanical device thus provides a programmable platform for engineering the mechanics of synthetic nano-vesicles and studying membrane tension modulated processes at the molecular level.

biophysics↗

Comparative Evaluation of DDA and DIA Based Proteomic Workflows in Beryllium Related Lung Disease

We compared traditional data-dependent acquisition mass spectrometry (DDA-MS) with the increasingly adopted data-independent acquisition (DIA-MS) to evaluate their relative utility for large-scale quantitative biofluid proteomics of lung compartments, specifically paired bronchoalveolar lavage (BAL) cells and bronchoalveolar lavage fluid (BALF). Using beryllium-related granulomatous lung disease as a focused model, we analyzed BALF and BAL cells from beryllium-sensitized (BeS) individuals using both acquisition strategies to assess proteome depth, quantitative completeness, and analytical robustness. In BAL cells, 5,640 proteins were identified by DDA-MS and 5,227 by DIA-MS; however, DIA-MS yielded markedly improved quantitative completeness, with 5,178 proteins ([~]99%) quantified across all samples compared with 3,539 ([~]63%) quantified by DDA-MS. While 3,397 proteins were quantified by both methods, DIA-MS uniquely quantified 1,781 lower-abundance proteins. Proteins identified by both DIA and DDA-MS approaches revealed pathways associated with granulomatous inflammation, including Toll-like receptor, clathrin-mediated endocytosis, sirtuin, and C-type lectin receptor signaling, whereas DIA-MS resolved additional pathways, such as the complement cascade, coagulation system, and JAK/IL-6-type cytokine signaling. In BALF, although more proteins were identified by DDA-MS than by DIA-MS (2,069 vs 1,742), DIA-MS achieved greater quantitative completeness, with 1,695 proteins quantified across all samples compared with 1,050 using DDA-MS, underscoring its suitability for biomarker-oriented analyses in lung fluid compartments. Together, these results support DIA-MS as a robust and sensitive platform for quantitative lung proteomics and discovery of disease-relevant protein signatures.

systems biology↗

Declining autophagy drives age-related axonal decay through microtubule alterations

The microtubule cytoskeleton plays a pivotal role in maintaining axonal integrity, and its deterioration has been closely associated with neuronal decay during ageing. Autophagy, a crucial cellular degradation process, is essential for sustaining neuronal homeostasis and its dysregulation has been implicated in various neurodegenerative diseases. Changes in autophagy are also associated with ageing. However, the mechanisms by which autophagy dysfunction contributes to neuronal atrophy in the ageing brain remain poorly understood. In this study, we unveil the significant involvement of autophagy in preserving axonal architectural integrity during ageing through regulation of the microtubule cytoskeleton. Our findings indicate that autophagic activity declines in neurons of the aged brain, and the inhibition of autophagy exacerbates age-related alterations in axonal and synaptic microtubules. This dysfunction correlates with an increase in established hallmarks of ageing, including swellings and thinning of axons plus synaptic terminal breakdown. Conversely, pharmacological and genetic strategies to enhance autophagic activity not only rescued age-related microtubule changes, but also inhibited the formation of axonal swellings, the thinning of axons and the deterioration of synaptic terminals. Mechanistically, we find that reactive oxygen species (ROS), a consequence of impaired autophagy, lead to alterations in microtubule networks. In addition, enhancing Eb1 expression can counteract the detrimental effects of deficient autophagy, effectively blocking axonal and synaptic microtubule deterioration. These findings underscore that alterations in autophagy are a critical driver of axonal deterioration during ageing, operating through modifications to the microtubule cytoskeleton as a downstream target. Our findings deliver a cascade of events that underlie neuronal ageing.

cell biology↗

SuFEx and macrocyclic chelation define orthogonal reactivity domains enabling isotopically versatile radiopharmaceuticals from a single peptide precursor

The design of radiotheranostic agents has been constrained by a fundamental chemical incompatibility: existing strategies for fluorine-18 incorporation -- nucleophilic substitution, silicon-fluoride exchange, aluminum fluoride chelation, and prosthetic conjugation -- either require conditions incompatible with macrocyclic metal coordination, consume the chelator site needed for radiometal labeling, or introduce non-native structural appendages that alter pharmacokinetic behavior. Here we show that sulfur(VI) fluoride exchange (SuFEx) chemistry and macrocyclic metal coordination define non-overlapping reactivity domains co-embeddable within a single peptide precursor. An aryl fluorosulfate on tyrosine accepts {superscript 1}F under mildly basic conditions; a spatially distinct macrocyclic chelator, DOTA, NOTA, NODAGA, or any compatible macrocycle, independently coordinates diagnostic (68Ga, 64Cu) or therapeutic (177Lu) radiometals under mildly acidic conditions. The labeling pathways proceed independently under mutually compatible conditions, and both preserve receptor-binding affinity. Validated across PD-L1- and CD38-targeting scaffolds, this platform delivers nanomolar target affinity, high radiochemical yields, and matched pharmacokinetics, establishing isotopic orthogonality as a designable, intrinsic property of synthetic molecular radiopharmaceuticals.

bioengineering↗

Neuronal ramping and theta power during freely-moving and head-fixed mouse interval timing.

An important paradigm to study executive function is interval timing, which requires participants to estimate a temporal interval, often with a motor response. Interval timing translates from rodents to humans and can model neurodegenerative and neuropsychiatric disease. Interval timing also has parallel, time-dependent neurophysiology in rodents and humans, including time-dependent linear changes in neuronal firing rates over a temporal interval (ramping activity) and low-frequency [~]4 Hz "theta" activity evoked by trial start and response. Despite these translational features, an important confound of interval timing is movement and motor preparation, as participants must report their estimates by planning a movement. To address this confound, we first trained a group of 7 mice in a freely-moving interval timing task in which mice had to move across an operant chamber and nosepoke at the correct time to receive food reward. These mice were then trained in a head-fixed version of interval timing in which mice receive liquid reward for holding still for 3 seconds at the correct location, with reward access randomized to probe interval timing behavior. Despite vastly different motor sequences, we found prominent ramping activity in mouse prefrontal cortex ensembles and prefrontal cortical [~]4 Hz activity evoked both by trial start and preceding the timed decision. These data provide evidence that prefrontal neuronal ramping and theta activity is not linked to a specific motor program but rather a feature of the temporal organization of behavior.

animal behavior and cognition↗

AGES for Ageing: Evaluating the auxin-inducible gene expression system for use in Drosophila ageing studies

Our research is only as good as our tools allow it to be. The fruit fly Drosophila has been a fundamental discovery platform in uncovering evolutionarily conserved biological underpinnings of ageing, due in large part to an ever-expanding functional genetic toolbox which permits fine-tuneable and cell-type-specific modulation of gene expression with relative ease. However, many existing gene expression systems present limitations for studying fly ageing, including off-target effects for inducing agents that allow temporal control. More recently-generated tools such as the auxin-based gene expression system (AGES) therefore present opportunities as potential alternatives in our methodological repertoire for ageing research. Here we have evaluated the AGES system in a variety of contexts in Drosophila ageing. We find that AGES can effectively induce transgene expression across a range of ages, albeit with tissue-specific efficiency. However, we also observe several phenotypes from auxin feeding, even in non-AGES genotypes, that may confound studies focused on ageing research, including reduced body mass and reduced survival under starvation and oxidative stress conditions. We also observe phenotypes from activating the AGES machinery, including shortened lifespan, that could present challenges for using AGES in longevity-based studies. Nevertheless, we find that AGES can be used to recapitulate at least some effects of well-established pro-longevity interventions - for instance reduced fecundity from expression of a dominant-negative form of the insulin receptor - reinforcing the value of AGES in certain domains. Taken together, our results underscore the need for caution and comprehensive controls in ageing studies that rely on functional genetics, regardless of the chosen genetic toolset.

genetics↗

Diabetes and Immunosuppression Drive Distinct Patterns of Candidozyma auris Skin Colonization and Dissemination in Mice

Candidozyma auris is an emerging, multidrug-resistant (MDR) fungal pathogen that persistently colonizes human skin and disproportionately causes invasive infections in patients with metabolic or immune dysfunction. Despite strong epidemiological links to diabetes and immunosuppression, how these host conditions shape skin colonization, immune defense, and dissemination remain poorly defined. Here, we establish complementary murine model of C. auris skin colonization under immunocompetent, immunosuppressed, and diabetic ketoacidosis (DKA) conditions. DKA mice exhibited significantly increased skin fungal burden, impaired clearance, and frequent systemic dissemination. Notably, DKA permitted dissemination despite preserved granulocyte and neutrophil recruitment to the skin, indicating a functional rather than quantitative defect in innate immunity. Consistent with this, phagocytes from DKA mice displayed impaired antifungal activity characterized by reduced phagocytosis and killing despite elevated reactive oxygen species production. Hyperglycemic and ketone-rich conditions (BHB) remodel the C. auris cell wall, reducing mannan, increasing chitin, and upregulating adhesins, thereby enhancing adhesion and inflammatory activation while impairing neutrophil killing. Together, these findings reveal host metabolic dysfunction as a primary driver of persistent C. auris skin colonization and dissemination, identify qualitative defects in innate antifungal immunity as a key determinant of invasive risk and highlight metabolic condition as a critical target for infection prevention strategies. Short SummaryThis study establishes the first physiologically relevant murine model of Candidozyma auris skin colonization under diabetic ketoacidosis and immunosuppression, revealing distinct immune dysfunction and systemic dissemination that can inform targeted antifungal strategies.

microbiology↗

Wnt activation prevents epileptogenic hippocampal remodeling in animal models of unilateral and bilateral temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is a heterogeneous disorder with most clinical presentations involving unilateral or bilateral hippocampal seizure onsets. Antiseizure medications are often ineffective for TLE, and epilepsy surgery can have variable outcomes. Risk factors for TLE are readily identifiable and typically precede chronic epilepsy, providing a window of opportunity for preventative treatments. However, there are currently no clinically approved anti-epileptogenic therapies. In this study, we investigate the role of Wnt signaling in epileptogenesis using two mouse TLE models, the intrahippocampal kainate model of unilateral TLE (IHK), and the intraperitoneal kainate model of bilateral TLE (IPK). We specifically examined adult-born immature dentate granule cells as these cells have been heavily implicated in the pathogenesis of TLE and clinical TLE is typically initiated in adulthood. We observed that adult-born immature dentate granule cells undergo pathological morphological changes during epileptogenesis in both the IHK and IPK models of TLE. When compared across epileptogenic zones, however, these changes differed between the two models. Wnt signaling also decreased in these cells in epileptic mice during the epileptogenic period. When mice were treated with SB415286, a highly selective Wnt activator, Wnt signaling in immature dentate granule cells was restored to baseline levels and pathological remodeling changes were reduced in both models. These data therefore suggest that a reduction in Wnt signaling in immature dentate granule cells plays an etiological role in epileptogenesis, and that restoring Wnt signaling using Wnt activating drugs or alternative agents may have therapeutic potential as an anti-epileptogenic strategy in TLE.

neuroscience↗

Mosquito-directed PROTACs to block malaria transmission

The mosquito stage of the Plasmodium falciparum life cycle is an attractive target for intervention since it is crucial for the sexual reproduction and transmission of parasites to human host. Mosquito determinants crucial for parasite infection and growth pose as lucrative targets for transmission blockers. Owing to the fact that p38 MAPK has role in immune response and vector competence, we have evaluated the potential of PROTAC molecule (NR-7h) to degrade Anopheles stephensi p38 MAPK (Asp38 MAPK), a conserved serine/threonine kinase involved in stress reactions, midgut homeostasis, and parasite survival. PROTAC-mediated degradation of Asp38 MAPK led to the disrupted development of the parasite, suggesting its crucial function in vector competence. Furthermore, NR-7h-treated mosquitoes showed higher expression of immune genes such Rel-2, TEP1, APL1, and NOS, suggesting that p38 MAPK regulates host immunity in a way that promotes parasite persistence. PROTAC-mediated degradation of target proteins, provides a more persistent and resistance-proof therapeutic effect than traditional kinase inhibitors. Our findings establish PROTACs as a novel vector-targeted strategy for the development of endectocides to limit malaria transmission.

molecular biology↗

Resolving heterogeneity of targeted lipid nanoparticles through solution-based biophysical analyses

Targeted lipid nanoparticles (tLNPs) represent the next frontier in nucleic acid therapeutics, enabling cell-specific delivery through covalent attachment of targeting ligands that drive receptor-mediated uptake. tLNPs are particularly promising for pregnancy-associated applications where precise on-target delivery is required to minimize maternal toxicity and protect fetal health. Yet, their rational design is limited by an incomplete understanding of how tLNP physicochemical properties influence biological performance. Conventional LNPs already exhibit pronounced heterogeneity in size, composition, and RNA loading, which is further amplified in tLNPs by variability in ligand attachment and surface density. Because traditional analytical methods report only ensemble-averaged properties, the nanoscale diversity of tLNPs remains unresolved. Here, we find that tLNP functional behavior is governed by previously inaccessible, structurally distinct tLNP subpopulations that are not captured by bulk measurements. We utilize asymmetric flow field-flow fractionation integrated with in-line UV spectral analysis, light scattering, and synchrotron small-angle X-ray scattering (AF4-UV-DLS-MALS-SAXS) to resolve ligand-dependent tLNP subpopulations that differ in size, shape, composition, and relative abundance. We find that protein conjugation preserves the internal lipid-RNA nanostructure of base LNPs but substantially increases particle heterogeneity, particularly for larger and multivalent targeting ligands. Despite increased heterogeneity, tLNPs functionalized with higher-avidity ligands achieve more effective targeted placental RNA delivery in mice, suggesting that binding avidity can offset the functional consequences of polydispersity. Chemometric SAXS analyses reveal that only SAXS-resolved tLNP subpopulations, not ensemble-averaged parameters, correlate with targeted placental transfection in vivo, whereas bulk-derived physicochemical metrics more strongly associate with nonspecific hepatic delivery. Together, this work harnesses a separation-coupled biophysical platform to resolve previously inaccessible tLNP subpopulations and demonstrates that subpopulation nanoscale structure, rather than bulk-averaged properties, dictates targeted RNA delivery. These insights provide a mechanistic foundation for rational engineering of next-generation precision targeted RNA LNP therapeutics.

bioengineering↗

Genome-wide analysis of Heavy metal ATPase (P1B-type ATPase) gene family in Mung bean and their expression analysis under heavy metal (Zn, Cd and Cu) stress

Heavy metal ATPases (HMAs) are important group of transmembrane proteins involved in homeostasis of metal ions in plant systems. In this study, a comprehensive analysis of genome assembly (VC1973A v7.1) resulted in the identification of nine HMA genes (VrHMA) and their corresponding proteins in Mungbean, an agronomically important legume crop known for its nutritional values. VrHMA proteins were also characterized based on their biomolecular features, conserved domains and motifs arrangement, transmembrane helices, pore-line helices, subcellular location and occurrence of signal peptides. Based on sequence homology, nine VrHMAs were clustered into two major substrate-specific groups: VrHMA1, VrHMA5 and VrHMA7 were categorized under the Zn/Co/Cd/Pb ATPase group, whereas the remaining six VrHMAs belong to the Cu/Ag subgroup. Gene structure analysis and promoter scanning revealed the structural divergence and presence of various stress-responsive cis-acting elements, respectively. The expression analysis of VrHMA genes in root and leaf tissues, in response to heavy metal (Zn, Cd and Cu) stress, indicates their role in the uptake, transport and sequestration of metal ions. Interestingly, VrHMA5 showed incremental upregulation in roots in response to all three heavy metal stresses, whereas its expression was only upregulated in the leaf tissues under Zn stress, which indicates its role in vascular transport in V. radiata. In addition, this study provides valuable insights into the functional roles of VrHMA genes and will lay a foundation for future genetic improvement in mung bean aimed at enhanced heavy metal stress tolerance and micronutrient homeostasis.

molecular biology↗

Osteoprotegerin-Enabled Immune Evasion by Pathological Adipose Stromal Cells Drives Metabolic Dysfunction in Obesity

Diet-induced obesity (DIO) promotes the accumulation of stromal cells with senescent characteristics in the adipose tissue (AT). Selectively clearing these cells--either through chemical senolytics or activation of invariant natural killer T (iNKT) cells--improves glucose homeostasis in obese mice, however the identity of the responsible stromal population remains unknown. Here, we use transcriptional profiling of AT stromal cells coupled with C12FDG-based enrichment of senescent populations in mice with DIO and healthy controls to identify a distinct subset of adipose progenitor cells (APCs) with robust senescence signatures that accumulate in DIO across multiple AT depots. We show that these cells, which we term senescent APCs (sAPCs), are not merely passive markers of metabolic stress but are instead active stromal organizers, accumulating in parallel with the emergence of lipid-associated macrophages (LAMs) and the diminution of multipotent mesenchymal progenitors. sAPCs promoted CCR2-dependent macrophage chemotaxis, directly linking stromal senescence to chemokine-mediated remodeling of the AT immune niche. Comparative transcriptional analysis revealed a remarkable similarity between sAPCs and inflammatory cancer-associated fibroblasts (iCAFs), including the strong induction of periostin (POSTN) and the production of osteoprotegerin (OPG), a decoy receptor for RANKL and TRAIL that enables tumoral immune evasion. Indeed, OPG production by AT stromal cells was induced by DIO across AT depots. Exogenous OPG inhibited the ability of iNKT cells to kill senescent APCs in vitro, whereas antibody-mediated OPG neutralization reciprocally enhanced such cytotoxic killing. In vivo, systemic OPG neutralization both reduced sAPC accumulation in AT and normalized glucose homeostasis in obese mice. Together, these findings identify sAPCs as a pathological stromal population that expands in obesity through elaboration of immunomodulatory factors. In particular, secreted OPG enables sAPCs to evade iNKT-mediated immune surveillance and contributes to metabolic dysfunction, highlighting OPG and sAPCs as promising therapeutic targets for restoring AT immune and metabolic homeostasis.

immunology↗

Two-Step Mechanism of Bruton's Tyrosine Kinase MembraneRecruitment and Activation

Peripheral membrane proteins (PMPs) are critical mediators of signaling cascades initiated via activation of cell-surface receptors. Their functions rely on their innate ability to interact with membranes dynamically in response to rapidly changing cellular conditions. This membrane recruitment may occur via high-affinity interactions with specific lipids or transient, low-affinity membrane interactions. These weak and dynamic interactions that are critical regulators of protein function are challenging to capture. Taking Brutons Tyrosine Kinase (BTK), a non-receptor tyrosine kinase essential for B cell activation, as an example, we demonstrate a native mass spectrometry (nMS) platform to understand the recruitment of PMPs by directly studying it from lipid bilayers customized to target membranes. Our data demonstrates that BTK recognizes phosphatidylserine (PS) through sites distinct from phosphatidylinositol (3,4,5) phosphate (PIP3) binding. We show PS-bound BTK retains PIP3 binding simultaneously via high-affinity sites, exhibiting PIP3-independent basal membrane recruitment of BTK. Biochemical assays show that this PS-mediated recruitment sensitizes BTK to PIP3-mediated activation under near-physiological concentrations of PIP3. Thus, we propose a two-step model for BTK membrane recruitment and activation. A low-affinity interaction with high-copy number PS enables plasma membrane recruitment of BTK and increases its membrane-bound concentration. Upon B-cell activation, this pre-recruited, membrane-bound BTK population localizes to PIP3-rich domains through electrostatic gliding along the membrane driven by low-affinity PS and high-affinity PIP3 binding. This indicates a cooperative mechanism where PS can amplify B-cell signaling through increased membrane-bound BTK concentration. Our work demonstrates a general model of PH-domain-containing protein regulation by weak protein-lipid interactions, which can be extended to many other PMPs.

biophysics↗

Low-intensity transcranial focused ultrasound engages parvalbumin-positive GABAergic interneurons in a humanized mouse model of chronic pain: from electrophysiology to cellular investigation

BackgroundLow-intensity transcranial focused ultrasound (tFUS) offers high spatial specificity and deep brain penetration, showing great promise as a non-invasive stimulation technology for modulating brain activity and behavior. Recent studies show that specific tFUS parameters targeted to pain-processing brain circuits can significantly alter pain-related behaviors in rodent models and humans. However, a comprehensive understanding of how tFUS influences brain networks and cellular mechanisms is essential to optimize efficacy and facilitate safe translation to clinical pain therapies. ObjectiveWe aimed to evaluate the modulation of inhibitory neural circuits induced by tFUS of 40 Hz pulse repetition frequency (PRF) in a humanized mouse model of chronic pain, integrating local and network-level electrophysiological investigations, molecular analyses, and histological assessment to confirm safety. Methods and ResultsWe used a 128-element random array transducer for stimulation, along with a non-invasive and flexible 30-channel electroencephalography (EEG) to assess local evoked responses, topographical brain activity, and global brain dynamics including excitation and inhibition (E/I) balance. To further assess tFUS neuromodulation effects at the cellular level, we performed immunohistochemistry (IHC) analysis and found that tFUS significantly increased the activity of inhibitory neurons as indicated by elevated expression of Glutamate Decarboxylase 67 (GAD67) and Parvalbumin (PV). Finally, safety was evaluated in the same brain samples used for mechanistic analysis, with blinded histological assessment revealing no signs of tissue damage. ConclusionsThese findings provide new evidence that tFUS non-invasively engages PV GABAergic inhibitory circuits in a chronic pain mouse model, supporting its development as a robust neuromodulation strategy. TopicsChronic pain; Transcranial focused ultrasound; Non-invasive brain neuromodulation; GABAergic neural circuit modulation HighlightsO_LIMulti-modal assessment of low-intensity tFUS in a humanized chronic pain model. C_LIO_LI40 Hz tFUS enhances inhibition, mirroring optogenetic PV neuron activation. C_LIO_LIRepeated tFUS restored chronic pain-disrupted E/I balance. C_LIO_LIMulti-session tFUS upregulates GAD67 and PV interneuron expressions. C_LI

bioengineering↗

TRIM62 promotes lipid raft-mediated entry of influenza A virus by regulating WASH localization

Viruses employ diverse strategies to gain entry into cells to reach their replication sites. Influenza A virus (IAV), a respiratory pathogen, takes advantage of clathrin-dependent endocytosis or macropinocytosis for its internalization. Here, we report that TRIM62, a member of the tripartite motif (TRIM) protein family, is required for IAV entry, independent of its E3 ubiquitin ligase activity. We find that TRIM62 specifically functions in a clathrin-independent, lipid raft-mediated pathway, which IAV exploits to enter the endocytic network. Additionally, we reveal the involvement of the WASH complex and the retromer component VPS35 in this pathway beyond their canonical functions in endosomal sorting. We observe that a pool of WASH and VPS35 localize to the plasma membrane and associate with lipid rafts, in addition to their typical endosomal presence. While WASH subunits except FAM21 play a proviral role in IAV endocytosis and intracellular trafficking, VPS35 acts antagonistically. We show that TRIM62 counteracts the antiviral function of VPS35 by limiting FAM21-VPS35 interaction. By directly binding WASH in the cytosol, TRIM62 restricts its VPS35-mediated endosomal recruitment and thereby enhances its surface availability to facilitate IAV entry. Together, this study uncovers previously unrecognized roles of TRIM62 and endosomal sorting machinery in IAV entry, offering new antiviral targets.

cell biology↗

Gasdermin C links nutrient and immune signaling to protist-induced type 2 immunity and intestinal repair

The Gasdermin family of proteins has recently been implicated in tissue repair and homeostasis through their effector function in type 2 immunity and pyroptosis. Yet the role of Gasdermin C proteins has not been fully characterized in the mammalian intestine, where environmental factors can influence epithelial regeneration and repair. Here we report that Gsdmc2-4 genes are regulated in a nutrient-dependent manner and are suppressed with aging. We uncover that commensal protists in the gut regulate Gsdmc2-4 expression through activation of type 2 immune responses. In intestinal organoid experiments, we find that STAT6 is necessary for Gsdmc2-4 induction in response to type 2 cytokines; however, basal expression of Gsdmc2-4 in vivo is only partially diminished in Stat6 knockout animals. Finally, in protist-colonized animals, loss of Gsdmc1-4 exacerbated mucosal erosion and inflammation in response to Dextran sodium sulfate (DSS) exposure, implicating these proteins in coordinating epithelial responses to injury.

physiology↗

Evaluating the Efficacy of Propofol Against Isoniazid-Induced Seizures: A Comparative Study with Diazepam and Pyridoxine in Swiss Albino Mice

ObjectiveAcute isoniazid toxicity causes refractory seizures due to pyridoxine deficiency-mediated gamma-aminobutyric acid depletion. While pyridoxine is the established antidote, its limited availability in emergency settings necessitates alternative treatments. This study aimed to evaluate the anticonvulsant efficacy of propofol, a GABA A receptor agonist and N-methyl-D-aspartate receptor antagonist, compared to pyridoxine and diazepam in isoniazid-induced seizures in mice. MethodsThirty-two Swiss albino mice were pretreated with: (1) normal saline (10 mL/kg), (2) pyridoxine (300 mg/kg), (3) propofol (50 mg/kg), or (4) diazepam (2.5 mg/kg), followed by isoniazid (300 mg/kg) after 30 minutes. All drugs were administered intraperitoneally. Seizure latency, duration, time to death, and survival were monitored for 120 minutes. Outcomes were analyzed using Kaplan-Meier/log-rank tests and ANOVA with Tukeys post-hoc test. ResultsIsoniazid induced seizures and 100% mortality in the control group. Pyridoxine did not prevent seizures or improve survival (8/8 seizures and deaths). Propofol failed to improve seizure frequency, latency, duration, mortality, or time to death (8/8 seizures and deaths). Diazepam significantly reduced seizure frequency and mortality to 1 of 8 mice (p < 0.001), and delayed seizure onset. ConclusionPretreatment with either propofol or pyridoxine failed to protect against isoniazid-induced seizures and death in mice. In contrast, diazepam was effective in preventing both seizures and death. Further studies are needed to investigate different propofol administration protocols and alternative animal models.

pharmacology and toxicology↗