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Pandey, R.

Publications and source records attributed to Pandey, R..

At least 19 recordsLinked to original sources

Isoflurane anesthesia CNS recovery state: ultra-slow oscillations and cellular-stress-responsive gene expression

General anesthesia and NREM sleep share slow-wave EEG features, yet whether anesthesia substitutes for physiological sleep remains unclear. We compared recovery from 4h of isoflurane anesthesia (IA) with time-matched sleep and sleep deprivation (SD) in male C57BL/6J mice using continuous EEG/EMG recordings and frontal cortex RNA sequencing. IA recovery produced transient, rebound arousal, reduced early NREM and REM sleep, and, fragmented subsequent NREM bouts, and persistant, ultra-slow EEG-oscillations that normalized within two weeks. Whereas, SD induced consolidated rebound sleep and slow wave activity. Transcriptomic profiling at ZT6 showed that IA and SD induced largely distinct cortical gene-expression programs. IA preferentially enriched integrated stress response and unfolded protein response genes, whereas SD showed a comparatively orthogonal, growth-permissive, mTOR-associated profile. Although IA-induced gene-expression suggests cellular stress, corticosterone measurements argued against systemic stress as the primary driver. These findings indicate that isoflurane recovery is neurophysiologically and molecularly distinct from restorative sleep.

neuroscience↗

Lactate epigenetically shapes tumor cell states in H3K27M diffuse midline gliomas

H3K27M diffuse midline gliomas (DMGs) are lethal and lack treatment options. These tumors exhibit tumor heterogeneity with aggressive oligodendrocyte precursor (OPC)- and mesenchymal (MES)-like cell states. Because all tumor cells bear H3K27M, tumor heterogeneity has been attributed to microenvironmental cues that remain obscure. H3K27M DMGs exhibit increased glycolysis and the Warburg effect to produce lactate. Lactate can directly modify histone lysines including H3K27Lac, and we hypothesized that lactate epigenetically regulates tumor cell states in H3K27M DMGs. We undertook a comprehensive and integrated analysis of H3K27M DMG cell lines, animal models, tumor tissues, and magnetic resonance spectroscopy in patients to decipher the epigenetic roles of lactate. Here, we report that H3K27M cells uniquely exhibit elevation of the activating mark H3K27Lac. We observed significant heterogeneity in lactate levels within tumors, and the addition of exogenous lactate resulted in marked increases in H3K27Lac and the expression of critical OPC- and MES- like gene signature genes, which correlates with poorer patient outcomes. Our therapeutic approach leverages the inhibition of CBP/p300, which deposits both H3K27Lac and H3K27ac. Targeting CBP/p300 effectively reduces both H3K27Lac and H3K27ac levels, suppresses key OPC- and MES-like signatures, and shows efficacy in preclinical models. Collectively, our findings identify lactate as a key player in the epigenetic regulation of tumor cell state heterogeneity and suggest that targeting this pathway offers promise for addressing the heterogeneous complexities of H3K27M DMGs.

molecular biology↗

Distinct Aβ40 and Aβ42 co-assembly pathways with free lipids: Experiment-driven MD study

Amyloid {beta}-protein (A{beta}), which is known for its role in Alzheimer's disease (AD), is also involved in several physiological functions. Of the two predominant isoforms, A{beta}40 and A{beta}42, the latter is more aggregation-prone and more active in health and disease. In the brain, A{beta} interacts with free lipids, which may affect its assembly pathways. Here, thioflavin T (ThT) fluorescence spectroscopy is combined with molecular dynamics (MD) to investigate A{beta}40 and A{beta}42 co-assembly with free dimyristoylphosphatidylcholine (DMPC) and DMPC/cholesterol (CHOL) lipids. ThT measurements at several protein-to-lipid (PL) ratios show isoform- and lipid composition-dependent kinetics of A{beta} fibril formation with clear isoform-dependent lipid effects at a PL ratio of 1:5. Early co-assembly stages of six A{beta}40/A{beta}42 with DMPC and DMPC/CHOL lipids at this PL ratio are then examined by MD. MD results indicate that lipids alter the secondary structure more and interact more avidly with A{beta}40 than with A{beta}42. In turn, A{beta}40 increases the planar order of lipid bicelles more than A{beta}42. Unlike A{beta}40, A{beta}42 decreases the nematic order of CHOL. In DMPC/CHOL lipids, A{beta}42 but not A{beta}40 exhibits two A{beta}-lipid interaction modes associated with mutually exclusive A{beta}42-lipid and A{beta}42-A{beta}42 interactions. Our MD findings provide a plausible explanation for an experimentally observed increase in the lag time for A{beta}40 fibril formation in DMPC lipids and even more so in DMPC/CHOL lipids that contrasts with much smaller effects of lipids on A{beta}42 fibril formation and offer additional atomistic-level insights into A{beta} co-assembly with lipids amenable to experimental testing.

biophysics↗

Tumor-specific CD4 T cells cooperate with myeloid cells to remodel the pancreatic tumor microenvironment and enable effective immunotherapy

We interrogate antigen-specific CD4 T cells during immunotherapy in pancreatic ductal adenocarcinoma. Vaccination with MHC-II-restricted tumor epitopes impart superior protection compared to an immunodominant MHC-I epitope, prompting development of MHC-II affinity-enhanced tetramers to track tumor-specific CD4 T cells. As tumors progress, tumor-specific CD4 T cells decline, and remaining cells acquire features of regulation. Agonistic anti-CD40 increases Th1 cell clonal expansion and transiently decreases Tregs. Anti-PD-L1 promotes Tfh clonal expansion in draining lymph nodes and tumor while preventing Treg rebound after anti-CD40. Treatment with anti-CD40 promotes intratumoral Stat1+ macrophages, tertiary lymphoid structures (TLS), and immune triads. MHC-II on myeloid cells but not B cells is required for immunotherapy-induced TLS formation and antitumor effects. IL-15 complex enhances immunotherapy-induced Th1 effectors without promoting Tregs. Human immunotherapy transcriptomics shows conserved Th1 programming and Treg destabilization as a feature of response. Thus, tumor-specific CD4 T cells are central mediators of effective immunotherapy in solid tumors.

immunology↗

A Dual-Function Guanidinium Scaffold that Couples Copper Sequestration with Redox Protection in Wilson disease

Wilson disease (WD) is caused due to mutations in the copper ATPase gene ATP7B, that result in accumulation of labile copper pools and the consequent disruption of cellular redox homeostasis through uncontrolled copper-mediated reactive oxygen species generation. Current therapies mainly depend on high-affinity copper chelation to lower metal burden which sometimes also strip copper from cuproproteins and may disturb physiological copper-dependent processes. It also does not directly suppress pathological copper reactivity i.e., free radical generation, a major driver of WD progression. To overcome these limitations, we have rationally designed Gua-Cu-3, a C-symmetric guanidinium-based molecule that can chelate labile copper without metal stripping from cuproproteins due to moderate binding affinity and it has intrinsic antioxidant activity within a single nanosheet-forming supramolecular self-assembly. Spectroscopic, calorimetric, and computational analyses revealed controlled multivalent copper coordination (Kd = 95.4 M) while radical-scavenging and hydroxyl-radical inhibition assays further revealed potent redox-regulatory activity. In cellular models of copper overload, Gua-Cu-3 treatment reduces ATP7B trafficking from trans-Golgi network, confirming effective intracellular copper sequestration. This was accompanied by a marked reduction in oxidative stress, reduction of translocation of Nrf2 in nucleus and of HO-1 expression, thereby limiting lipid peroxidation which leads to restoration of cellular homeostasis, including improved lysosomal integrity, reduced endoplasmic reticulum stress, decreased mitochondrial superoxide levels, and diminished apoptosis. Importantly, the protective effects extended, beyond cultured cells, Gua-Cu-3 attenuates oxidative stress in ATP7B-homolog-deficient C. elegans and rescues copper-induced developmental defects in zebrafish, outperforming D-penicillamine, which is currently in use for Wilson disease management. These findings establish Gua-Cu-3 as a molecularly designed supramolecular copper-reactivity buffer that couples-controlled copper sequestration with redox regulation which is distinct from conventional copper depletion and provides a framework for treating Wilson disease and other disorders associated with metal dyshomeostasis and oxidative stress.

Cell Biology↗

Copper-transporting ATPase ATP7B and the lysosomal exocytosis pathway synergise to detoxify cadmium

Cadmium, being a highly toxic metal, perturbs cellular homeostasis by forming stable complexes with numerous thiol-active proteins, ultimately leading to severe liver and lung damage. Despite its well-documented toxicity, the molecular mechanisms governing cadmium export remain poorly understood. Given the chemical similarity between cadmium and copper, we investigated whether the canonical copper-exporting ATPases, ATP7A and ATP7B participate in cadmium handling. Upon Cd treatment in hepatocytes, ATP7B undergoes trafficking to lysosomes via the retromer complex, as also observed in the case of elevated copper, accompanied by the upregulation of acidic lysosomal populations. In contrast, ATP7A expressed in lung adenocarcinoma cells, though exhibit vesicular redistribution upon Cd exposure, does not mediate lysosomal sequestration, suggesting distinct deployment of late secretory pathways by the two copper ATPases in response to cadmium. We have also observed that ATP7B-/- hepatocytes exhibit increased sensitivity to Cd exposure compared to wild-type cells. Whereas, overexpressing the ATP7B amino-terminal copper-binding domain in bacteria alleviates cadmium-induced stress, indicating its capacity to sequester Cd. Caenorhabditis elegans lacking copper-ATPase cua-1, displayed increased Cd sensitivity, while mutants (glo-1-/-), deficient in lysosome-related organelles (LRO), and (lmp-1-/-), deficient in lysosomal membrane glycoprotein, showed reduced resistance to cadmium toxicity. Treatment of the worm with cadmium increases the abundance of lysosomes marked by elevation in lysosomal biogenesis and functional genes, reinforcing the importance of lysosomal pathways in cadmium detoxification. To summarise, we delineated the non-canonical role of copper ATPases and lysosomes in cadmium-induced cellular toxicity.

cell biology↗

A comparative analysis of urinary microbiome identifies putative probiotics

Urinary tract infections (UTIs) are the most prevalent bacterial infections globally, and their management increasingly challenged by antimicrobial resistance (AMR). Probiotics offer a promising approach to mitigate AMR by competitively excluding uropathogens and enhancing host immunity by producing immune modulators. Despite being potential, key gaps persist between the discovery of uroprotective probiotic strains and optimization of formulations for urinary tract delivery. Here, we analyzed the urinary microbiome of UTI patients and healthy individuals to identify potential probiotic candidates for the prevention and management of UTIs. Publicly available 16S rRNA amplicon sequencing data of the urinary tract were processed using a standardized pipeline for sequence quality assessment, taxonomic assignment, and microbial function prediction. Comparative analysis showed a significant shift in microbial composition between UTI patients and healthy controls. The dominated phyla identified included Acidobacteriota, Actinobacteriota, Bacteroidota, Campylobacterota, Cyanobacteria, Firmicutes, Fusobacteriota, Patescibacteria, Proteobacteria, and Synergistota. Overall differential abundance analysis revealed Escherichia coli as the predominant UTI-associated species, while Lactobacillus crispatus was enriched in healthy samples. Additionally, predictive functional analysis indicated that metabolic pathways associated with beneficial microbes were enriched in the healthy group. Overall, the study highlights the association of distinct urinary microbiome signatures with infection status, which supports L. crispatus as the most promising probiotic for UTI prevention and control.

bioinformatics↗

PS FAD mutants and γ-secretase inhibition accumulate VEGFR2-derived peptide VCTF1 suppressing brain VEGFR2 dimerization, angiogenesis and neuroprotection.

Efficient cerebrovasculature is vital to neuronal health and cognition and evidence shows that most dementia patients have cerebrovascular abnormalities. Brain vasculature is regulated by Vascular Endothelial Growth Factors (VEGFs) binding VEGF receptor2 (VEGFR2) and stimulating angiogenesis and neuroprotection. Here we show that an ADAM17 cleavage of extracellular VEGFR2 produces the membrane-bound {gamma}-secretase substrate VEGFR2/CTF1 (called VCTF1), comprising the transmembrane and intracellular domains of VEGFR2. VCTF1 binds full-length VEGFR2 monomers suppressing its dimerization a function that is required for VEGFR2 activation and downstream angiogenesis and neuroprotection. Presenilin1 (PS1) Familial Alzheimers disease (FAD) mutants exert dominant negative effects on the {gamma}-secretase processing of VCTF1 increasing its concentration and abolishing VEGF-A-induced VEGFR2 dimerization/activation and downstream VEGFR2 signaling, endothelial cell functions and angiogenesis. {gamma}-Secretase inhibitors or PS1 reduction have similar effects on VCTF1 accumulation and VEGFR2 dimerization/activation and downstream signaling and functions as PS1 FAD mutants. Moreover, PS1 FAD mutants increase vulnerability of brain neurons to ischemic stress and abolish VEGF-A-induced neuroprotection and cognition. Together, these data show that VCTF1 suppresses VEGFR2 dimerization and downstream signaling and functions of the brains VEGF-A-/VEGFR2 angiogenic and neuroprotection systems. Importantly, we detected molecular markers of decreased VEGFR2 dimerization and angiogenic dysfunction in human brain tissue from PS1 FAD mutant genotypes. Our data reveal a pathway through which FAD mutants may promote dementia by increasing accumulation of VCTF1 and decreasing angiogenesis, neuroprotection, and cognition, suggesting that PS1 FAD patients may benefit from therapeutic methods that decrease brain VCTF1.

neuroscience↗

A Long-lived Avatar for Modeling Age-Related Vascular Disease

BackgroundCurrent microphysiological models do not support long-term investigations into the chronic effects of vascular risk factors and the development of vascular diseases. Prolonged culture frequently leads to cellular senescence and loss of functional integrity, resulting in variability and inconsistency in modeling chronic vascular responses. Here we aimed to develop and sustain a long-term multicellular human vascular avatar, addressing the critical need for long-term disease modeling and drug testing. MethodsTo identify the optimal media for longevity, cell identity and function were assessed by morphology, qPCR, beta-gal staining, ELISA, bulk RNA-seq and single cell RNA-seq analysis. After optimizing the culture media, iPSCs-derived ECs and VSMCs from unaffected and Hutchinson-Gilford Progeria Syndrome (HGPS) donors were grown in Gravitational Lumen Patterning (GLP) Vessel- Chips for 1-6 months to generate a long-lived vascular avatar for the study of vascular aging. ResultsGuided by quantitative morphological analyses and bulk RNAseq profiling, we generated a novel optimized culture media VSL (VEGF, SB431542 as a TGF-{beta} inhibitor, low fetal bovine serum) that enhances the long-term health of vascular endothelial cells (ECs). Furthermore, we modified the VSL formulation (mVSL) by modulating 8Br-cAMP, FGF, PDGF, and a cell viability enhancer HMH1015 levels to enhance EC-VSMC (vascular smooth muscle cell) crosstalk and support long-term cellular viability. Subsequently, we maintained and characterized a human vascular avatar with a three-dimensional extracellular matrix environment and 3D vascular architecture for over 180 days. Finally, we demonstrated that this long-lived human vascular avatar enabled modeling vascular aging using iPSC-derived vascular cells from patients with Hutchinson-Gilford Progeria Syndrome (HGPS). ConclusionsWe have successfully engineered and maintained a human vascular avatar for over 180 days. The vascular avatar provides a robust platform for modeling disease-associated vascular aging and for evaluating therapeutic strategies targeting chronic vascular disorders.

bioengineering↗

Extending the limits of 3D printed polymers on paper towards bioanalytical sensing

Polymeric 3D printing of microfluidic devices for biosensing is an appealing fabrication alternative for rapid manufacturing of biosensing devices with complex geometry in a streamlined, repeatable and cost-effective manner without the need for expensive instrumentation such as those employed in photochemical etching and soft lithography. Hybrid 3D printed paper-based microfluidics is an emerging area which harnesses the unique properties of both, merging the construction of microfluidic structures and the inherent capillary-driven flow within paper substrates. In this work, we have fabricated hydrophobic barriers by 3D printing a single layer of machinable wax, thermoplastic polyurethane, polylactic acid and polypropylene directly on chromatography paper to create open microchannels and determine the most suitable material. Characterization of each open microchannel using the four materials revealed polypropylene as the most reliable material with high hydrophobic barrier integrity and resolution. Polypropylene achieved functional microchannels with a resolution of 621 {+/-} 33{micro}m, hydrophobic barrier integrity of (93.75 {+/-} 9.16%), wicking speed of 0.38mm/s and optimal hydrophilicity of channels (51.4 {+/-} 8.36 {degrees}) with minimal embedding during thermal curing. To demonstrate proof of principle, a fluorescence assay demonstrating the formation of a dimeric g-quadruplex structure from a g-rich sequence which significantly enhances fluorescence of thioflavin T was implemented.

molecular biology↗

Label-free toehold mediated strand displacement on 3D printed hybrid paper-polymer platform for protein sensing

A programmable 4-input cascade DNA logic gate utilizing toehold mediated strand displacement (TMSD) was implemented on a 3D printed hybrid paper-polymer vertical flow device (3D HPVF) for on/off sensitive and specific fluorescence detection of platelet derived growth factor BB (PDGF BB). Polypropylene was 3D printed directly on paper and thermally cured to create micro paper analytical devices ({micro}PADs). The 3D HPVF comprised of three layers of {micro}PADs enclosed in a casing that clamped each {micro}PAD securely to ensure seamless and efficient wicking between layers. In the presence of PDGF BB, a partially complementary strand to a PDGF B aptamer (PDGF B Apt), cApt, was liberated from a PDGF B Apt/cApt duplex in solution. The solution was then deposited on the 3D HPVF with a dimeric g-quadruplex hairpin. The 4-nucleotide toehold region on the cApt started the hybridization reaction with the dimeric g-quadruplex hairpin (dGH) opening it up allowing formation of a dimeric g-quadruplex structure that binds with thioflavin T (ThT) with enhanced fluorescence intensity at room temperature. The 3D HPVF exhibits a pico molar range of detection from 10pM to 100pM with a 10pM limit of detection (LOD) for PDGF BB concentrations relevant for pregnant women predisposed to early-onset preeclampsia with clear differentiation when compared to similarly competing analytes PDGF AA and AB.

molecular biology↗

Spatial Variation in Cortex Glia Cell Cycle Supports Central Nervous System Organization in Drosophila

Cortex glia (CG) in the ventral nerve cord (VNC) utilize mechanisms such as endocycling and acytokinetic mitosis to increase their nuclear count and support neighboring neural cells. However, the regulation of their cell cycle is not well understood. Our study examines larval development and reveals that CG nuclei in the thoracic region (tVNC) undergo successive rounds of replication and division, exponentially increasing their number to form a syncytial network around neural cells. In contrast, nuclei in the abdominal region (aVNC) only enhance their DNA content by endocycling. Key regulators, including cyclins and cyclin-dependent kinases, are vital for managing replication and division in CG. Notably, the M-phase regulator String (stg) is crucial for maintaining diploidy in tVNC nuclei and facilitating syncytial network formation. We demonstrate that ectopic stg expression can induce nuclear division in hyperploid aVNC CG. This study highlights regulatory mechanisms in CG, emphasizing the importance of region-specific cell cycle regulation for nervous system organization.

developmental biology↗

A human iPSC-derived motor neuron-myogenic cell coculture platform to evaluate neuromuscular junction innervation after axon injury and in Spinal Muscular Atrophy

Traumatic nerve injury is challenging as motor neurons with damaged axons repair slowly, which can lead to muscle degeneration, while in Spinal Muscular Atrophy (SMA), muscle innervation is reduced. While pro-regenerative or neuroprotective compounds have been identified, their specific ability to enhance or restore neuromuscular junction (NMJ) function in patients remains unclear due to a lack of in vitro human models that track axon growth, NMJ innervation and muscle function. We developed a human iPSC-derived motor neuron-myogenic coculture platform that enables real-time monitoring of axon growth NMJ innervation and axon regeneration and muscle activity following axonal injury, and for SMA-derived motor neurons. We identified spontaneous synchronized GCaMP6f muscle activity as a useful functional marker of NMJ formation. Using this platform, we show that blebbistatin, a pro-regenerative non-muscle myosin II (NMII) inhibitor differentially regulates growth cone dynamics in injured versus uninjured motor neurons, resulting in enhanced NMJ reinnervation. This highlights the therapeutic potential of developing pro-regenerative compounds to promote NMJ innervation. We also confirm that NMJ function is reduced in SMA type 0 (prenatal onset) and type I (pediatric onset) patient-derived motor neurons in the coculture. This human stem cell-based framework can be used, therefore, to evaluate pro-regenerative compounds for axon injury and neuroprotective one for neurodevelopmental and neurodegenerative disorders.

neuroscience↗

Harnessing Lytic Phages for Biofilm Control in Carbapenem-Resistant Klebsiella pneumoniae Causing Urinary Tract Infection

BackgroundKlebsiella pneumoniae is a major opportunistic pathogen with rising multidrug resistance and biofilm-related infections. Molecular and phage characterization is crucial to understand resistance mechanisms and explore alternative therapies such as phage therapy. MethodsWe performed whole-genome sequencing and antibiotic susceptibility testing of hospital-isolated Klebsiella pneumoniae (KP6697). MLST, plasmid replicon analysis, and resistance gene identification were conducted using bioinformatics. Phage isolation, electron microscopy-based morphological and biofilm analysis, and evaluation of lytic activity, stability, and host range were performed. Phage genome sequencing and annotation identified functional genes. ResultsThe host strain Klebsiella pneumoniae (KP6697) was multidrug-resistant, exhibiting resistance to 18 of 22 tested antibiotics, and genome analysis identified ST16 with eight plasmid replicons and 23 resistance genes, including blaCTX-M-15, blaNDM-5, and blaOXA-181. Functional annotations revealed extensive metabolic versatility and a rich repertoire of genes for biofilm formation, quorum sensing, secretion systems, and stress response. A lytic phage, Phage_KP6697_Omshanti, was isolated and classified as a Caudoviricetes member with a 45.3kb genome encoding lysis, replication, and structural genes. It demonstrated short latency, high burst size, thermal and pH stability, and broad host range against CRKP and other MDR strains. Importantly, microscopy confirmed its ability to inhibit and degrade biofilms at multiple stages, highlighting strong therapeutic potential. ConclusionComprehensive analysis of carbapenem-resistant K. pneumoniae (KP6697) revealed multidrug resistance and strong biofilm formation. The lytic phage Phage_KP6697_Omshanti, with depolymerase and endolysin activity, disrupted biofilms, and its stability, high burst size, and genomic traits suggest potential as an anti-CRKP agent, especially with antibiotics IMPORTANCEKlebsiella pneumoniae is increasing multidrug resistance and robust biofilm formation pose severe clinical challenges, limiting treatment options. Understanding the molecular basis of its resistance and exploiting bacteriophages with strong biofilm-disrupting properties provide promising alternative therapeutic strategies. This study highlights the isolation and genomic characterization of a lytic phage with potent anti-biofilm activity against carbapenem-resistant K. pneumoniae, underscoring its potential in combating resistant infections.

microbiology↗

Identification of donor landraces for early vegetative stage salinity tolerance in wheat by employing multivariate selection indices

Soil salinity (EC of [≥]4 dS m-1) is a major abiotic stress leading to decreased crop production due to osmotic, ionic, and cellular ionic imbalance balance. The current study aims to identify salinity-tolerant wheat landraces by investigating morpho-physiological traits. Three hundred fifty wheat landraces and check lines were evaluated for salt stress (15 dS m-1) tolerance in a hydroponic set-up. The clustering analysis categorized 350 genotypes into four control and 15 dS m-1 conditions clusters. Across the multi-trait genotype-ideotype distance index (MGIDI), Smith Hazel Index (SHI), and Stress Susceptibility Index (SSI), seven genotypes were consistently identified as tolerant among the top 150. In comparison, 12 genotypes were consistently classified as least tolerant. These identified tolerant landraces serves as important resources and novel salt tolerance donors for wheat. The tolerant*sensitive, tolerant* tolerant check, crosses can be used for generating RIL populations to delineate genetic basis of salt tolerance of newly identified lines.

physiology↗

Repurposing Melatonin in dual-mode for Wilson disease therapy as a Copper Chelator and an antioxidant agent

Loss-of-function mutations in copper-ATPase ATP7B underlie Wilson disease (WD), a disorder characterized by hepatic copper accumulation and severe hepato-neuropathology. Existing chelation therapeutics remove excess copper but lack intrinsic antioxidant capacity and frequently cause systemic toxicity. Here we evaluate melatonin, an FDA-approved indoleamine with antioxidant and putative metal-chelating activity, as a candidate therapeutic for WD. In ATP7B-/- hepatocytes, melatonin restored copper-induced reactive oxygen species (ROS) to basal levels, reduced apoptosis twofold, and attenuated Nrf2 nuclear translocation leading to reduction of Hemoxygenase-1 abundance. Live-cell ratiometric analysis of GSSG/GSH using GRX1-roGFP2 expressed in melatonin-treated ATP7B-/- hepatocytes revealed a significant reduction in intensity-ratio, indicating an effective mitigation of copper-induced glutathione oxidation. Isothermal calorimetric titration revealed moderate Cu2+ affinity (K ITC=4.54 x 103 M-{superscript 1}), rationalized by MD-simulations showing an interaction energy of 18.5 x 10-3 kcal{middle dot}mol-{superscript 1} via amide-Cu{superscript 2} coordination. In-cellulo studies also revealed that copper-induced vesicularized ATP7B reinstates to Golgi in melatonin-treated hepatocytes. In vivo, melatonin treatment reduced copper-induced oxidative stress in zebrafish embryos and lowered copper burden in Caenorhabditis elegans WD model. Our studies revealed that encapsulation of melatonin within an engineered polymeric nanocapsules having dithiol linkers, susceptible to cleavage by GSH, extended melatonins circulatory half-life ten-fold and enhanced its ROS-scavenging efficacy three-fold relative to free melatonin. This work introduces a unique dual-function therapeutic strategy that integrates antioxidant activity with copper chelation, simultaneously addressing copper overload and redox imbalance. Repurposing melatonin, with its established clinical safety, offers rapid and cost-effective translational pathway toward WD-therapy while providing a generalizable platform for redox- and metal-associated disorders.

cell biology↗

Association of haplotypes of AAP family amino acid transporters with nitrogen response and nitrogen use efficiency in rice grown under hydroponics and field conditions

The low nitrogen use efficiency (NUE) of staple food crops like rice has both economic and environmental impact. Amino acids taken up from soil or synthesized in source tissues and transported to sink tissues influence plant development and NUE. Amino acid permeases (AAPs) mediate amino acid uptake and transport and influence plant development, yield and NUE. NUE is a complex trait critical for improving rice productivity under variable N supply. Amino acid permeases such as OsAAP3, OsAAP5, and OsAAP11 have been shown to function as negative regulators of NUE in Japonica rice, yet their roles in Indica rice remain to be fully elucidated. In this study, we evaluated selected Indica genotypes under contrasting N regimes--seedlings were tested under high nitrate (HN), high ammonium (HA), and low N (LN) conditions, and field performance was assessed under N120 (optimum N) and N0 (low N). Our aim was to relate performance differences to the SNP status in these three genes, thereby clarifying their influence on N uptake, assimilation, yield potential, and N stress adaptation. ARC 10799 had non-synonymous SNP in OsAAP3, OsAAP5 and OsAAP11. Rice accessions like "Local," "NCS901," and "Bhainsa Mundariya," showed superior biomass accumulation relative to MTU1010. Interestingly, the trend observed in the NUE calculated in seedling stage was similar to those proven in field evaluation and this proves that in general, genotypes with non-synonymous mutation in AAP3, AAP5 and AAP11 in comparison to Japonica showed better growth and N content. Data suggests an N induced regulation of physiological parameters and the changes in NUE parameters was at least in part, related to variation in biomass, plant height, photosynthesis and pigment content related parameters. The comparatively dissimilar trends in shown by different AAP haplotypes indicates the possibility of high or low correlation trait-wise, offering an opportunity to identify significant contrasts in a divergent set of AAP haplotypes. The previous reports and current findings opens new avenues and insights for improving rice yield, quality and NUE by changes in AAP haplotypes that occur naturally or created by precise genome editing.

plant biology↗

Modeling the Co-Activation of Inflammatory Genes1Mediated by NFκB and IRF-3 During Viral Infections

Innate immune responses of host cells are activated upon exposure to external stimuli such as viral infections. These activations trigger the signaling pathways involved in antiviral responses. Activated pathways play a crucial role in the regulation of inflammatory and antiviral responses involving transcription factors, cytokines, cell surface viral sensors, and the activation of target genes. Although the role of key transcription factors such as NF-{kappa}B and IRF-3 in the regulation of antiviral genes that encode type I interferons (IFN/{beta}) is identified and well explored. The precise mechanistic understanding that governs their complex context-dependent temporal activation remains elusive. Here, we have developed a mathematical model to demonstrate the co-regulation of the expression of the IFN{beta} gene by Nuclear Factor kappa B (NF{kappa}B) and IFN Regulatory Factor-3 (IRF-3) after their activation in host cells by the viral analogue Poly I:C. In our model, the binding activities of the transcription factors NF{kappa}B and IRF-3 at the IFN{beta} promoter are modeled using a probability-based framework. Our results demonstrate that the expression pattern of IFN{beta} postviral infections would be pertaining to the co-activation of that by NF{kappa}B and IRF-3. In addition, the immediate expression of the IFN{beta} gene and, thus, the initial host response would be mainly attributed to immediate activation of NF{kappa}B while IRF-3 would be responsible for delayed but persistent expression of the IFN{beta}. Our model provides an underlying molecular mechanism for a similar response observed for Newcastle disease virus and the Vesicular stomatitis virus infection. Furthermore, we suggest that the rapid as well as an elevated and persistent expression of IFN{beta}, would be observed later due to a temporal bias in binding of both transcription factors NF{kappa}B and IRF-3, highlighting the need for coregulation of IFN{beta} by two different signaling pathways in a sequential manner. Also, our model predicts that the binding affinity of IRF3 to the promoter region of IFN{beta} would be equal to or larger than that of NF{kappa}B for a strong and persistent antiviral responses.

systems biology↗