Biology subjects

Sharma, B.

Publications and source records attributed to Sharma, B..

At least 19 recordsLinked to original sources

bioRxiv2026

The annexin A1 mimetic peptide Ac2-26 promotes inflammation-resolution and stimulates skeletal muscle regeneration in the mdx mouse model of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked disorder mainly affecting young boys characterized by repeated cycles of myofiber injury/regeneration and chronic muscle inflammation. Although glucocorticoids can slow disease progression, their potential long-term adverse effects highlight the need for new steroid-sparing therapies for DMD. Annexin A1 (ANXA1) is a glucocorticoid-induced pro-resolving protein that signals primarily through formyl peptide receptor 2 (FPR2). We investigated whether the ANXA1 mimetic peptide Ac2-26 could reduce inflammation, stimulate tissue regeneration, and improve skeletal muscle function in muscular dystrophy. 3-week-old dystrophin-deficient male mdx mice were randomized to receive daily intraperitoneal injections of vehicle control, deflazacort (1 mg/kg/day), or Ac2-26 (1 mg/kg/day) for a duration of 5-weeks. Body composition, skeletal muscle mass, contractile function, and tissue histopathology/immune-cell infiltration were assessed at 8-weeks of age. Direct effects on myogenesis were also examined in vitro using primary D2-mdx myoblasts. ANXA1 was expressed predominantly by myeloid cells rather than resident dystrophic muscle cells. Both deflazacort and Ac2-26 markedly reduced intramuscular inflammation and increased myofiber size. However, Ac2-26 produced broader anabolic and functional benefits, increasing body-weight gain, lean body mass, hindlimb muscle weights, and absolute contractile force. Ac2-26 treatment also directly promoted myogenesis of dystrophic myoblasts in vitro, while pharmacological FPR2 blockade impaired myotube development. Overall, Ac2-26 mimicked the anti-inflammatory effects of deflazacort while providing superior benefits for body weight and composition, skeletal muscle growth, myofiber regeneration, and absolute muscle strength. These findings support therapeutic targeting of the ANXA1-FPR2 axis as a potential safe and effective steroid-sparing immunomodulatory strategy for DMD.

cell biology↗

bioRxiv2026

Metabolic disease-relevant stimuli unmask context-dependent genetic regulation of cardiometabolic loci in human adipocytes

Genome-wide association studies (GWAS) have identified thousands of loci associated with cardiometabolic disease, yet translating these associations into regulatory mechanisms, effector genes, and cellular programs remains a major challenge. A key limitation is that genetic effects are often highly context dependent, varying across cell states and environmental conditions that are difficult to model at scale. Here, we leverage CellGenBank, a population-scale biobank of primary human adipose-derived mesenchymal stem cells (AMSCs), to implement a multi-donor cell village in vitro system to map cardiometabolic disease genetic variation across adipocyte differentiation and metabolic stress conditions. We pooled AMSCs from 118 donors into multiplexed villages, differentiated them toward adipocytes, and profiled chromatin accessibility and gene expression using single-nucleus multiome sequencing under four disease-relevant conditions: basal, elevated free fatty acids, low glucose, and hypoxia. By combining with genetic demultiplexing, we quantify how regulatory element activity, gene expression, and higher-order cellular programs are modulated by both genotype and environmental context. Across conditions, we identify widespread context-specific cis-regulatory effects, including expression and chromatin accessibility quantitative trait loci that are masked in baseline states. Genetic effects frequently converge on coordinated transcriptional programs linked to lipid metabolism, insulin responsiveness, and stress adaptation, enabling the identification of cellular program QTLs that bridge variants, genes, and disease-relevant phenotypes. Integration with cardiometabolic GWAS reveals enhanced colocalization in condition- and state-resolved analyses, highlighting the importance of modeling environmental context to resolve disease mechanisms. Together, our study establishes large-scale adipocyte cell villages as a powerful and generalizable framework to map the context-dependent regulatory architecture of cardiometabolic disease and provides a resource linking human genetic variation to adipocyte cellular programs.

genomics↗

bioRxiv2026

Farming and climate legacies shape the seed microbiota and offspring drought responses in wheat

Seeds link parental environments to offspring establishment, but whether seed-associated bacteria retain signatures of farming and climate legacies across plant generations remains unclear. Here, we characterized epiphytic and endophytic bacterial communities of winter wheat seeds collected from the Global Change Experimental Facility (GCEF) in Germany across three harvest years representing contrasting climates. We then tested how farming (organic versus conventional) and climate (ambient versus future) legacies experienced by maternal plants were associated with offspring rhizosphere bacterial communities and plant performance under drought in the greenhouse. Harvest year was the dominant driver of grain dry weight and seed-associated bacterial communities. Climate legacy additionally affected seed epiphytic communities, whereas farming legacy was expressed in the endophytic diversity. Germination was higher overall for seeds from the conventional than the organic farming legacy and from the ambient than the future climate legacy. A small subset of unique seed-associated ASVs was detected in offspring rhizospheres. Although these ASVs occurred at low relative abundance in seeds (<1%), they accounted for up to approximately 40% of rhizosphere relative abundance under drought. Together, these findings show that seeds retain bacterial signatures of parental farming and climate legacies and that a subset of seed-associated ASVs remains detectable and can become abundant in offspring rhizospheres under drought.

microbiology↗

bioRxiv2026

Learnable Graph Network Model (LGNM): A Physics Constrained Graph Neural Network with Quantum Hamiltonian Learning

Elastic Network Models (ENMs), particularly the Gaussian Network Model (GNM) and its distance-weighted variant (mENM), predict per-residue protein flexibility from C contact graphs at low computational cost. Their central limitation is the assumption of uniform spring constants, which ignores the chemical identity, burial depth, and evolutionary conservation of individual residue contacts. We introduce the Learnable Graph Network Model (LGNM), a heterogeneous ENM in which per-edge spring constants{theta} ij = fi {middle dot} fj {middle dot} (dc/rij)2 are parameterised by per-residue flexibility coefficients {fi} predicted by a physics-constrained Graph Neural Network (GNN). The GNN is trained on molecular dynamics (MD)-derived root-mean-square fluctuation (RMSF) profiles from 413 proteins in the ATLAS database, using fold-disjoint CATH superfamily splits. The learning objective is an instance of the Quantum Neural PDE (QNPDE) Hamiltonian learning framework, with K = 3 operator types enabling an O(K) quantum gradient versus O (N3) classical pseudo-inversion. On 91 held-out test proteins, LGNM achieves mean per-protein Pearson correlation r = 0.8549{+/-} 0.1055, versus r = 0.8024 {+/-} 0.1167 for mENM ({Delta}r = +0.0525; 77/91 proteins improved). The implementation of this methedology is aviliable at https://lgnm.compbiosysnbu.in/ allowing researchers to evaluate flexibility and downstream processses.

bioinformatics↗

bioRxiv2026

Dietary omega-6 arachidonic acid and omega-3 docosahexaenoic acid supplementation differentially impact skeletal muscle inflammaging in mice

Aging is associated with a gradual and progressive decline in skeletal muscle mass and strength known as sarcopenia, which has been attributed to chronic low-grade inflammation. Dietary long-chain polyunsaturated fatty acids (LC-PUFAs), including omega-6 arachidonic acid (ARA) and omega-3 docosahexaenoic acid (DHA), are precursors to bioactive lipid mediators that regulate the initiation, propagation, and active resolution of inflammation. While traditionally considered a pro-inflammatory and catabolic factor, the ARA-derived eicosanoid prostaglandin E2 has recently emerged as a potential anti-sarcopenic molecule. DHA-derived specialized pro-resolving mediators may also act as immunomodulatory pro-regenerative molecules in muscle inflammaging. In the current study, we tested the effects of long-term dietary supplementation with either ARA or DHA on muscle health in aging mice. Twenty-two-month-old C57BL/6N mice were fed a control AIN-93M diet, or an AIN-93M diet supplemented with either ARA (0.48% w/w) or DHA (0.48% w/w) for 12 weeks. Both dietary interventions reduced total body weight, but only ARA reduced absolute fat mass and increased the percentage of lean mass. Despite these changes in body composition, ARA supplementation reduced absolute muscle strength and myofiber size. This functional decline was associated with increased neuromuscular junction fragmentation, elevated expression of pro-inflammatory cytokines/protein degradation markers, and suppressed ribosome biogenesis. In contrast, DHA uniquely reduced chronic inflammation of aged muscle and returned c-Myc expression to young levels but did not affect muscle mass or strength. These data demonstrate that long-term dietary intake of ARA and DHA have overall divergent effects on the structure and function of aging muscle.

physiology↗

bioRxiv2026

Towards Reliable Tracking of Natural Killer Cells Using Commercial Iron Oxide Nanoparticles and Magnetic Particle Imaging

Non-invasive tracking of natural killer (NK) cells remains a major challenge in cancer immunotherapy, limiting our understanding of their in vivo migration and persistence. Magnetic particle imaging (MPI) offers a quantitative, real-time method for visualizing labeled cells, yet optimal labeling protocols for NK cells have not been established. Here, we evaluate commercially available iron oxide nanoparticles (IONPs) for MPI labeling of both NK92MI cells and primary human NK cells. Labeled cells retained viability and cytotoxicity, including activity against three-dimensional tumor spheroids, and were detectable by MPI. To further examine imaging performance in a biologically relevant context, we employed mouse phantoms that recapitulate organ-specific signal distributions, enabling evaluation of quantification and liver spillover effects. We identify key tradeoffs between particle colloidal stability and per-cell iron content: VivoTrax and VivoTrax Plus provided higher MPI signal but required post-labeling purification, reducing cell recovery, whereas Synomag-D and Perimag were more stable and preserved cell yield despite lower signal intensity per cell. These results provide a framework for selecting nanoparticles that balance detection sensitivity, cell viability, and workflow practicality, advancing non-invasive NK cell tracking.

bioengineering↗

bioRxiv2026

Differential effects of α-Synuclein monomers and seeds on the material properties of Tau condensates

Tau and -Synuclein (Syn) frequently co-aggregate in various neurodegenerative disorders. Recently, Tau has been shown to form dynamic, liquid-like condensates that can recruit Syn, and potentially serve as a precursor to pathological aggregation. However, the quantitative impact of Syn on the material properties of these condensates remains elusive. Here, we measure the viscosity and interfacial tension of Tau condensates and determine how these properties are modulated by Syn monomers and fibril seeds. We find that while both forms of Syn partition efficiently into Tau condensates, they exert vastly different effects on the condensates material state. The viscosity of Tau condensates remains unchanged in the presence of Syn monomers at concentrations up to 200 {micro}M, accompanied by a moderate reduction in the condensates interfacial tension. In contrast, the addition of only 5 {micro}M Syn fibril seeds triggers rapid solidification of Tau condensates, manifested by a nearly 100-fold increase in condensate viscosity within one hour. These findings provide quantitative insights into condensate mechanics, highlighting the unique capacity of Syn seeds to drive the liquid-to-solid transition of Tau condensates that may underlie the formation of pathological aggregates.

biophysics↗

bioRxiv2026

Modulation of liposome membranes by the C-terminal domain of the coronavirus envelope protein

The coronavirus envelope (E) protein is a viroporin that plays a key role in viral assembly, release, budding and pathogenesis. E protein forms oligomeric ion channels that can activate immune responses. However, high-resolution structural data for its extramembrane domains is limited. The C-terminal domain of SARS-CoV has been shown previously to form amyloid fibers, and here we show that these fibers can modulate the shape of liposomes. The propensity to form fibrils, and their effect on liposomes, was examined for sequences belonging to the four clades of coronaviruses. Electron microscopy data shows that the C-terminal domain in E protein adopts a filamentous structure. These findings demonstrate the potential of these peptides to modulate membranes, providing a possible mechanism by which E protein interacts with membranes in the host cell.

biophysics↗

bioRxiv2026

Ultrasensitive, Low-Input Detection of Avocado Sunblotch Viroid via RPA-CRISPR and Nanopore-Array Single-Bead Fluorescence Readout

Rapid and sensitive detection of plant pathogens, such as the Avocado Sunblotch Viroid (ASBVd), is essential for early disease management and agricultural biosecurity. Yet, most current diagnostic methods not only require relatively large sample inputs but also often lack the ultrasensitivity required for reliable detection with scarce or minimally collected plant material. Here, we report a novel low-input but ultrasensitive diagnostic platform that integrates isothermal recombinase polymerase amplification (RPA), CRISPR-Cas12a detection, and a solid-state nanopore array for the detection of ASBVd. The system leverages CRISPR-Cas12a collateral cleavage activity to generate single-bead fluorescent signals, which are captured by a nanopore array through pressure-driven blockage. Our platform achieves a detection limit down to 1.68 copies/L while using only 40 nL of bead-fluorophore mixture per readout, which is over 100-fold less than conventional assays based on fluorescent readout using an imaging reader, enabling detection from minimal avocado sample collection. We demonstrate robust binary classification of ASBVd-positive and -negative samples from multiple avocado tissue types and orchards in California. The assay requires just 60 minutes and operates entirely under isothermal conditions, avoiding the need for bulky PCR instruments and supporting on-site deployment with minimal equipment. This method provides a promising platform for field-deployable, ultrasensitive, and low-input diagnostics of viroids and other low-titer pathogens in plant or clinical settings.

bioengineering↗

bioRxiv2025

Shape-Dependent Toxicity of Gold Nanoparticles in Microalgae: Distinct Cellular and Molecular Responses

The ecotoxicological effects of engineered nanoparticles in aquatic environments are influenced not only by composition and size but also by particle morphology, yet shape dependent interactions with primary producers, remain poorly understood. In this study, we evaluated the cellular and molecular responses of freshwater algae (Chlamydomonas reinhardtii) following exposure to 100 nm silica-coated gold nanospheres (AuNP) and nanostars (AuNS) across multiple concentrations. Exposure to 10 mg/L AuNS for 72 h results in significantly stronger inhibition of algal growth and photosynthetic activity compared to the same concentration of AuNP. Morphometric profiling reveals that AuNS induced pronounced structural injury, including cell enlargement, debris production, and disruption of subcellular organization than AuNP. Confocal imaging suggested this heightened toxicity may stem from distinct internalization patterns, with AuNP primarily adhering to chloroplast surfaces, whereas AuNS penetrated more deeply into intracellular compartments. RNA sequencing identified 9 upregulated and 38 downregulated differentially expressed genes (DEGs) in the 10 mg/L AuNP treated cells, impairing photosynthesis and energy storage via the photosystem II subunit S1 (PSBS1)/ early light-inducible protein (ELI3) pathway. In contrast, the AuNS group exhibits 246 upregulated and 145 downregulated DEGs, affecting membrane integrity and nitrogen metabolism through the nitrate reductase (NIT1)/ aminomethyl transferase (AMT1)/ protein kinase domain-containing protein (A0A2K3CRU5) pathway. These results demonstrate that nanoparticle morphology can drive divergent toxicity mechanisms in algal cells. Our findings highlight the necessity of incorporating NPs morphology into environmental risk assessments and suggest that safer nanomaterial design should consider shape-dependent interactions with aquatic microorganisms. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=115 SRC="FIGDIR/small/694526v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@29fbccorg.highwire.dtl.DTLVardef@5221a7org.highwire.dtl.DTLVardef@1f6249org.highwire.dtl.DTLVardef@6dc054_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2025

Silicon Micropillar-Enhanced CRISPR Biosensor for Rapid and Sensitive Detection of Drug-Resistant Bacteria

1The growing threat of antibiotic-resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), underscores the urgent need for rapid, sensitive, and field-deployable diagnostic technologies. Here, we present a silicon micropillar-enhanced CRISPR biosensor that integrates high-aspect-ratio microstructures with a one-pot RPA/CRISPR-Cas12a assay for ultrasensitive and specific detection of MRSA. Micropillar arrays with fixed diameters and varying heights (100 {micro}m, 300 {micro}m, and 500 {micro}m) were fabricated via deep reactive ion etching and functionalized for surface probe immobilization. Suboptimal crRNA design was employed to modify Cas12a activation kinetics, enabling declined trans-cleavage and enhanced end-point signal accumulation. The 500 {micro}m micropillar configuration demonstrated a tenfold improvement in sensitivity compared to the 100 {micro}m array, with a limit of detection reaching 103 CFU mL-1. The platform also showed high specificity against non-target bacterial strains. These findings highlight the potential of combining microstructured chips with one-pot CRISPR diagnostics to advance next-generation point-of-care tools for infectious disease monitoring. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=184 SRC="FIGDIR/small/694528v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@5f5f7corg.highwire.dtl.DTLVardef@175cb35org.highwire.dtl.DTLVardef@7043e5org.highwire.dtl.DTLVardef@79aa15_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2025

Soil microbial legacies and cultivar compatibility modulate the responses of wheat to drought

Global climate change stressors are altering soil function and reducing crop yields, yet the role of soil microbial legacies in shaping plant stress responses remains poorly understood. Here, we tested how long-term farming (organic vs conventional) and climate (ambient vs future) histories of soil microbiomes influence wheat performance under drought. Soil samples were collected from long-term experimental plots of the Global Change Experimental Facility (GCEF, Germany) and used to extract microbial communities, which were then used to inoculate sterilized potting soil in which two wheat cultivars, drought-sensitive Nordkap and drought-tolerant SU Fiete, were grown under controlled greenhouse drought. Our results showed that microbial inoculation enhanced germination relative to non-inoculated, with conventional-ambient microbiomes most strongly promoting emergence, while organic-future microbiomes suppressed seed germination. Under drought, aboveground fresh biomass and dry weight content diverged by interaction between cultivar and microbial legacy in such a way that Nordkap performed best with future-climate microbiomes, whereas SU Fiete benefited from ambient-climate microbiomes. The rhizosphere of plants inoculated with organic-derived microbes harbored a larger unique ASVs, with 442 bacterial and 70 fungal ASVs, compared with 381 bacterial and 48 fungal ASVs unique to conventional-derived microbes. We further showed that rhizosphere bacterial communities were influenced by complex interactions between microbial history (farming and climate), cultivar, and water stress, while fungal communities tracked only farming history, with organic legacies buffering fungal diversity under drought. Together, these results demonstrate that soil microbiomes retain the imprint of past management and climate, and that these legacies can either buffer or exacerbate plant stress responses depending on host genotype.

ecology↗

bioRxiv2025

Evidence for an indigenous female mouse urobiome

Mice have been used as a valuable model of understanding pathophysiological mechanisms of urinary tract infection for almost six decades. Mice offer many advantages including genetic manipulation to test the role of genes and mechanisms, the availability of germ-free mice, and similarities to humans in innate immune defenses and the strain-dependent presence of vesicoureteral reflux. However, like with humans, the mouse bladder urine above the urinary sphincter has generally been assumed to be sterile. Yet, given the presence of urobiomes in other mammals and the emerging role of the human urobiome in the defense of the urinary bladder and upper urinary tract, the existence of a mouse urobiome should be critically examined as indigenous microbiota may influence experimental results. To determine if an indigenous murine urobiome exists, we obtained expressed urine from two sets of female C57BL/6J mice during three different intervals using two different extraction and sequencing methods and analyzed them simultaneously by a single method. For one set, we also obtained urine by suprapubic aspiration, which we compared to the paired expressed urine samples. We conclude that an indigenous murine urobiome exists and that expressed urine contains post-urethral microbes.

microbiology↗

bioRxiv2025

Serum exosome miR-150-5p in rheumatic heart disease-associated angiogenesis

The focus of this study is on Rheumatic heart disease (RHD), an autoimmune consequence of rheumatic fever leading to mitral valve damage. Aim is to explore the role of exosomes derived from RHD patients in promoting angiogenesis during RHD pathogenesis. Exosomes were isolated via column chromatography from the pericardial fluid (PF) and serum of RHD patients, pericardial fluid from non-RHD patients undergoing coronary artery bypass grafting (CABG) surgery, and serum of healthy individuals. These exosomes were characterized by transmission electron microscopy (TEM) and western blotting. Human umbilical vein endothelial cells (HUVECs) cultured from umbilical cord(s), were treated with purified exosomes from RHD, CABG patients or healthy individuals. Exosome treatment induced morphological changes in HUVECs, including elongation and tube-like structure formation. The qRT-PCR gene expression analysis revealed significant upregulation of angiogenic markers (VEGF-A 2.7-fold, MMP2 1.5-fold) and inflammatory cytokine (IL-4 15.17-fold), in HUVECs stimulated with RHD serum exosomes. Conversely, there was downregulation of anti- angiogenic genes (RASA-1 0.65-fold and endostatin 0.4-fold). Notably, elevated levels of miR- 150-5p (34.29 + 9.524-fold mean difference; p= 0.0007) were detected in serum-derived exosomes from RHD patients compared to healthy controls. Stimulation of HUVECs with RHD serum exosomes resulted in reduction in the expression of TP53 (0.227-fold; p= 0.006), a known target of miR-150-5p. Furthermore, transfection of HUVECs with miR-150-5p mimics induced the formation of angiogenic endothelial tubes, underscoring the role of miR-150-5p in promoting angiogenesis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/659484v1_ufig1.gif" ALT="Figure 1000"> View larger version (27K): org.highwire.dtl.DTLVardef@1520e92org.highwire.dtl.DTLVardef@3aa03aorg.highwire.dtl.DTLVardef@ed6e1dorg.highwire.dtl.DTLVardef@1d85231_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2025

Leukocyte-type 12/15-lipoxygenase is essential for timely inflammation-resolution and effective tissue regeneration following skeletal muscle injury

Unlike traditional anti-inflammatory therapies which may interfere with musculoskeletal tissue repair, pharmacological administration of specialized pro-resolving lipid mediators (SPMs) can promote timely resolution of inflammation while stimulating skeletal muscle regeneration. Despite this, the potential role of endogenous inflammation-resolution circuits in skeletal muscle injury and repair remains unknown. Here, we investigated the effect of whole-body knockout of leukocyte-type 12/15-lipoxygenase (12/15-LOX) on acute inflammation and regeneration following skeletal muscle injury in mice. Prior to muscle injury, Alox15-/- mice displayed lower intramuscular concentrations of 12/15-LOX-derived lipid mediators than wild type (WT) mice, and this was associated with chronic low-grade muscle inflammation. Alox15-/- mice mounted an exaggerated acute immune response to sterile skeletal muscle injury which was associated with a local imbalance of pro-inflammatory vs. pro-resolving lipid mediators. During the regenerative phase, Alox15-/- mice displayed defects in myogenic gene expression, myofiber size, and myonuclear accretion. Mechanistically, bone marrow-derived macrophages (M[FE]) obtained from Alox15-/- mice produced less 12/15-LOX-derived lipid mediators and this was associated with impaired M2 polarization. Isolated myogenic progenitor cells also produced many LOX metabolites in response to long chain polyunsaturated fatty acid (LC-PUFA) supplementation, including bioactive SPMs. Alox15-/- myoblasts were both impaired in their ability to produce SPMs and were insensitive to the stimulatory effect of LC-PUFAs on in vitro myogenesis. These data show that the 12/15-LOX pathway is essential for timely resolution of acute inflammation and direct determination of myogenic progenitor cell fate following skeletal muscle injury.

developmental biology↗

bioRxiv2025

3D Chemotaxis Chip for Investigating Natural Killer Cell Migration Mechanisms

IntroductionNatural killer (NK) cells are a promising tool for cancer immunotherapy, as they can rapidly recognize and kill cancer cells without prior knowledge of tumor-specific antigens while leaving healthy cells unharmed. However, a major challenge in NK cell-based therapies is their inadequate infiltration and function within solid tumors. Advancements in NK cell therapies for solid malignancies require a better understanding of the various factors that influence NK cell migration to and within the tumor microenvironment. MethodsThe objective of this study was to develop a chemotaxis chip with a tunable 3D hydrogel that enables the spatiotemporal analysis of NK cell migration. Results/DiscussionBy manipulating the 3D hydrogel or inhibiting key integrin and protease interactions, we found that NK cells heavily relied on protease-dependent migration but could leverage other mechanisms for faster migration. Additionally, when hyaluronic acid, an important extracellular matrix component in tumors, was incorporated into the hydrogel, NK cells migrated faster and farther in the chemotaxis chip. ConclusionThis study establishes a novel migration assay to observe NK cell behavior in real-time, providing a platform for investigating the mechanisms of NK cell migration and identifying strategies to improve NK cell trafficking within solid tumors.

bioengineering↗

bioRxiv2025

Sex- and estrous-specific effects of paradoxical (REM) sleep deprivation: Neurobehavioral changes and hippocampal neuroinflammation

With millions suffering from sleep disorders in todays modern society, a better understanding of sleep disruption related cognitive outcomes is urgently needed. To that end, a preclinical investigation into the effects of sleep deprivation (SD) on neurobehavioral outcomes and associated hippocampal neuroinflammation was conducted in male and female rats. Due to epidemiological identification of sex differences in many aspects of sleep disorders, sex and estrous cycle stage factors were investigated. Sprague-Dawley rats underwent 120 h of paradoxical SD using a modified multiple platform flower pot method. At 96 h SD, animals were trained on neurobehavioral Novel Object Recognition (NOR) and Passive-Avoidance Task (PAT) paradigms. Prior to NOR/PAT testing at 120 h SD, Elevated Zero Maze (EZM) assessed anxiolytic-like behavior. SD impaired PAT performance among males and females. Anxiolytic-like and locomotor behavior was increased and NOR performance impaired in males after SD. Estrous cycle stage determined by cytological analysis of daily wet smears found females to exhibit estrous-specific differences across all neurobehavioral paradigms, with increased anxiolytic-like behavior and impaired PAT performance only among SD females in estrus. Immunohistochemical analysis of the hippocampus after 120 h SD found microgliosis, but not astrogliosis, in the CA1/2 of males and females in estrus. This study contributes to a better understanding of sex- and estrous-specific difference in sleep disruption induced neurobehavioral outcomes and associated hippocampal inflammation. Further research is needed to investigate the molecular mechanisms underlying the interaction between estrous cycle, hippocampal microgliosis, and sleep disruption cognitive outcomes.

animal behavior and cognition↗

bioRxiv2025

MicroRNAs alteration and unique distribution in the soma and synapses of substantia nigra in Parkinsons disease

Parkinsons disease (PD) is the second most common neurodegenerative condition after Alzheimers. Abnormal accumulation of alpha-synuclein (-syn) aggregates disrupts the balance of dopaminergic (DA-ergic) synapse components, interfering with dopamine transmission and leading to synaptic dysfunction and neuronal loss in PD. However exact molecular mechanism underlying DA-ergic neuronal cell loss in the SNpc in not known. MicroRNAs (miRNAs) are observed in various compartments of neural elements including cell bodies, nerve terminals, mitochondria, synaptic vesicles and synaptosomes. However, miRNAs expression and cellular distribution are unknown in the soma and synapse compartment in PD and healthy state. To address this void of information, we isolated synaptosomes and cytosolic fractions (soma) from post-mortem brains of PD-affected individuals and unaffected controls (UC) and processed for miRNA sequencing analysis. A group of miRNAs were significantly altered (p < 0.05) with high fold changes (variance +/- > 2-fold) in their expressions in different comparisons: 1. UC synaptosome vs UC cytosol, 2. PD synaptosome vs PD cytosol, 3. PD synaptosome vs UC synaptosome, 4. PD cytosol vs UC cytosol. Our study unveiled some potential miRNAs in PD and their alteration and unique distribution in the soma and synapses of SNpc in PD and controls. Further, gene ontology enrichment analysis showed the involvement of deregulated miRNAs in several molecular function and cellular components: synapse assembly formation, cell junction organization, cell projections, mitochondria, Calcium ion binding and protein binding activities.

neuroscience↗