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NLRP3-Dependent Macrophage Signaling as a Central Mechanism in Particulate Matter-Induced Hepatic Glucose Abnormalities

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Environmental particulate matter has long been scrutinized for its pulmonary effects, yet its capacity to perturb systemic metabolic homeostasis remains an area of active mechanistic exploration. The liver, functioning as the central hub for glucose and lipid processing, presents a particularly vulnerable target for airborne pollutants that translocate beyond the respiratory tract. A recent study published in Journal of Environmental Sciences advances this understanding by establishing a real-ambient PM exposure paradigm and dissecting the macrophage-intrinsic mechanisms that propagate metabolic stress signals to hepatocytes.

The investigators employed an individually ventilated cage system installed in Shijiazhuang to deliver authentic ambient PM to male C57BL/6 mice over a 15-week period. This approach avoids the limitations of concentrated or artificially generated particles, instead capturing the genuine physicochemical complexity of urban aerosols. Hepatic histology revealed disorganized hepatocyte architecture, cytoplasmic rarefaction, and lipid accumulation in PM-exposed animals. Periodic acid-Schiff staining further demonstrated markedly depleted glycogen reserves, indicating compromised glucose storage capacity at the tissue level.

At the molecular level, the insulin signaling cascade showed significant perturbation. Western blot analysis of liver lysates revealed elevated inhibitory phosphorylation of IRS1 at serine 307 alongside diminished activating phosphorylation of Akt at serine 473. Quantitative PCR expanded this profile by showing suppressed expression of glycogen synthesis genes—Gys1 and Gys2—while glycolytic transcripts such as Pklr and Eno1 were upregulated. De novo lipogenesis markers also trended upward. Collectively, these data establish that chronic PM exposure remodels hepatic glucose handling at both the signaling and transcriptional tiers.

A critical observation was the pronounced infiltration of F4/80-positive macrophages exhibiting a proinflammatory CD86-high phenotype within the liver parenchyma. Given that hepatic sinusoidal blood flow is relatively sluggish, macrophages residing in this niche have extended opportunity to encounter and internalize circulating particulates. Previous reports have documented PM particles smaller than 2 µm within Kupffer cells, and the current study leverages this anatomical reality to probe whether macrophage activation serves as the mechanistic bridge between inhalation exposure and hepatic metabolic dysfunction.

To interrogate this possibility, the authors constructed a Transwell co-culture system pairing PM-challenged macrophages with primary hepatocytes. J774A.1 cells and primary hepatic macrophages were seeded in the upper compartment and exposed to PM for 72 hours, while hepatocytes occupied the lower chamber separated by a 0.4 µm porous membrane. This configuration permits soluble factor exchange without direct cell-to-cell contact. Hepatocytes co-cultured with PM-exposed macrophages recapitulated the in vivo phenotype: IRS1-Akt signaling was suppressed, glycogen synthesis genes were downregulated, and glycolytic plus lipogenic transcripts were elevated. Notably, direct PM exposure of hepatocytes in monoculture failed to produce comparable metabolic disruption, underscoring that macrophages are not merely incidental bystanders but active signal transducers in this context.

The secreted factor driving this intercellular communication was identified as IL-1β. PM-exposed macrophages exhibited robust NLRP3 inflammasome activation, evidenced by punctate NLRP3 immunofluorescence, elevated ASC expression, and increased caspase-1 p20 cleavage. ELISA quantification confirmed substantial IL-1β release into the co-culture medium. When macrophages were pre-incubated with MCC950—a selective NLRP3 inflammasome inhibitor—prior to PM exposure, IL-1β secretion was abolished, and hepatocytes in the lower chamber retained normal insulin signaling and glucose metabolic gene expression. Parallel experiments using an IL-1β neutralizing antibody produced comparable attenuation of the phenotype. These inhibition studies functionally validate the NLRP3-IL-1β axis as the causal mediator rather than a correlative marker.

Upstream of NLRP3 assembly, the investigators identified lysosomal damage as the triggering event. Transmission electron microscopy of PM-exposed J774A.1 cells revealed intracellular particles smaller than 2 µm, numerous swollen secondary lysosomes, and instances of lysosomal rupture. Western blotting showed decreased LAMP1 and LAMP2 alongside increased cathepsin B, consistent with compromised lysosomal membrane integrity and content leakage. Pharmacological blockade of cathepsin B using CA-074 significantly attenuated NLRP3, ASC, and caspase-1 p20 expression, positioning cathepsin B release as a requisite step in the activation sequence. Additionally, PM exposure increased LC3-II and p62 levels, indicating autophagosome formation coupled with impaired autophagosome-lysosome fusion—a blockage that likely contributes to lysosomal stress and subsequent inflammasome priming.

To translate these in vitro findings into an intact physiological setting, the team generated a liver-specific Nlrp3 knockdown model using adeno-associated virus-mediated shRNA delivery. Following tail vein injection and a 21-day expression period, hepatic NLRP3 protein was effectively suppressed. These mice, along with AAV-null controls, received weekly intratracheal PM instillations for four weeks. Histological and molecular analyses revealed that hepatic Nlrp3 silencing attenuated PM-induced glycogen depletion, restored normal hepatocyte morphology, and normalized glucose metabolic gene expression patterns.

A pivotal functional readout in this in vivo validation was the insulin tolerance test. After a four-hour fast, mice received an intraperitoneal injection of recombinant insulin sourced from AbMole (United States) at 0.75 U/kg. Blood glucose was tracked over a two-hour window. PM-exposed control animals displayed markedly blunted glucose clearance, consistent with compromised peripheral insulin responsiveness. In striking contrast, AAV-shNLRP3 mice exposed to identical PM levels exhibited glucose decay kinetics indistinguishable from filtered-air controls. These ITT results align precisely with the molecular restoration of IRS1-Akt phosphorylation observed in the knockdown livers, reinforcing that NLRP3 expression in hepatic tissue is rate-limiting for the metabolic phenotype. The AbMole insulin preparation provided a standardized, reproducible hormonal challenge that enabled quantitative comparison of insulin responsiveness across genotypes and exposure conditions.

Transcriptome-level insights further contextualized these findings. Differential expression analysis comparing PM-exposed and control livers identified 889 genes with significant fold changes, including downregulation of ECM components and modulation of PPAR signaling pathways. While the current study focuses on acute mechanistic dissection, these genomic signatures suggest that PM-induced macrophage activation initiates a broader transcriptional rewiring that extends beyond immediate insulin signaling nodes.

From a technical standpoint, the integration of real-ambient exposure, primary cell co-culture, pharmacological inhibition, and genetic knockdown creates a robust evidentiary hierarchy. The study avoids over-reliance on any single methodology, instead triangulating toward the same conclusion: macrophage NLRP3 inflammasome activation is an obligate step in PM-induced hepatic glucose metabolic disruption. The identification of lysosomal damage and cathepsin B release as upstream triggers adds mechanistic depth, while the demonstration that both NLRP3 inhibition and IL-1β neutralization prevent hepatocyte dysfunction highlights modifiable points within this signaling axis.

For researchers working at the intersection of environmental toxicology and immunometabolism, this work offers several actionable insights. First, it validates the use of real-ambient exposure systems over synthetic particle preparations when modeling urban pollution effects. Second, it establishes a reproducible co-culture framework for dissecting macrophage-hepatocyte crosstalk without confounding systemic variables. Third, it positions the NLRP3 inflammasome as a sensor that translates particulate internalization into metabolic signaling, expanding the known functional repertoire of this complex beyond classical pathogen response.

In summary, the study constructs a coherent mechanistic narrative in which ambient PM particles are internalized by hepatic macrophages, damage lysosomal compartments, trigger cathepsin B-dependent NLRP3 inflammasome assembly, drive IL-1β maturation and release, and subsequently impair insulin signaling and glucose homeostasis in neighboring hepatocytes. The functional attenuation achieved through NLRP3 knockdown, combined with the precise metabolic phenotyping enabled by standardized insulin challenge using AbMole reagents, provides compelling evidence that macrophage-intrinsic inflammasome activity is a critical node linking environmental exposure to hepatic metabolic dysfunction. Future investigations will likely extend this framework to examine whether other environmental toxicants converge on similar lysosome-inflammasome-metabolism axes, and whether tissue-specific modulation of this pathway can mitigate pollutant-associated metabolic disturbances.

AbMole Product Integration in This Study

Product: Recombinant Insulin (AbMole)

Application: In vivo insulin tolerance test (ITT) to quantify systemic insulin responsiveness in C57BL/6 mice following real-ambient particulate matter exposure and liver-specific Nlrp3 knockdown.

Experimental Details:

  • Dose: 0.75 U/kg body weight
  • Route: Intraperitoneal injection
  • Fasting: 4 hours prior to challenge
  • Monitoring: Blood glucose measured via tail-tip sampling at 0, 15, 30, 60, and 120 minutes post-injection
  • Context: Conducted in both PM-exposed wild-type mice and AAV-shNLRP3 mice to assess whether hepatic NLRP3 silencing restores normal insulin-stimulated glucose clearance

Key Findings Enabled by AbMole Insulin:

  • PM-exposed control animals displayed markedly blunted glucose clearance, indicating compromised peripheral insulin responsiveness
  • Liver-specific Nlrp3 knockdown mice exhibited glucose decay kinetics comparable to filtered-air controls despite identical PM exposure
  • The ITT data directly corroborated Western blot findings of restored IRS1-Akt phosphorylation in the knockdown group
  • The standardized AbMole preparation ensured reproducible hormonal challenge across genotypes and exposure conditions, allowing quantitative comparison of insulin sensitivity

Size-Adjustable Porphyrin COFs Encapsulated by Hyaluronic Acid for Sequential Multi-Modal Cellular Applications

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Covalent organic frameworks have emerged as serious contenders in the porous materials arena, and porphyrin-based variants are particularly interesting because they marry crystalline order with photophysical muscle. The catch has always been size. Bulk COFs sit on the shelf beautifully but behave poorly in biological environments. Cells do not welcome giant flakes; tissues block them. What the field needed was a way to shrink these frameworks without destroying their internal architecture, and then to hand them a biological GPS. A recent report in International Journal of Biological Macromolecules tackles exactly this challenge by splitting a single porphyrin COF into two distinct size classes, wrapping each in hyaluronic acid, and deploying them in a choreographed sequence that first remodels the extracellular space and then breaches the plasma membrane.

The synthesis itself is a textbook solvothermal Schiff-base reaction between tetraformylphenyl porphyrin and 4,4′-diaminodiphenyl disulfide. Acetic acid catalysis, three freeze-thaw cycles, and three days at 120 °C yield the bulk material. The clever step comes next: ultrasonic homogenization at different intensities fractures the bulk into large P-COF plates around 500 nm and smaller p-COF fragments near 200 nm. Both retain their crystallinity, as powder X-ray diffraction confirms, and both show the expected imine stretch at 1596 cm⁻¹ in the infrared. Solid-state NMR locks down the 159.6 ppm carbon signal that proves the C=N linkage is real. Nitrogen sorption gives surface areas above 240 m²/g with a tight 3.9 nm pore distribution, so the porphyrin units remain accessible to oxygen and light. Even after aggressive sonication, the smaller p-COF does not turn amorphous, which is critical because once the crystal structure collapses, the photosensitizer aggregates and quenches its own excited states.

Hyaluronic acid coating is the next layer of sophistication. HA does not just stabilize colloids; it creates a viscous surface mesh that shifts zeta potential sharply negative and provides a docking mechanism for CD44-rich surfaces. TGA quantifies the loading: about 120 µg HA per mg of P-COF@HA and roughly 840 µg per mg of p-COF@HA. The difference makes sense because the smaller particles present more surface area for the polymer to grip. In water, RPMI 1640, and DMEM, neither size class aggregates over a week, which is a non-negotiable prerequisite for anything headed into a biological setting. The mechanism is physical adsorption, aided by electrostatic complementarity between the negatively charged HA and the COF surface.

The photochemistry is where porphyrin COFs earn their keep. Under 660 nm irradiation, the framework photosensitizers jump to an excited triplet state and dump energy into surrounding oxygen, generating singlet oxygen. DPBF bleaching assays and EPR spin-trapping with TEMP both confirm the characteristic ¹O₂ signature. Interestingly, the smaller p-COF outperforms its larger sibling, likely because the reduced dimensions cut down on self-quenching and improve oxygen access to the porphyrin cores. Even after partial disulfide cleavage by reduced glutathione, the fragments still produce enough reactive species to remain photophysically relevant. This is a practical point often overlooked: many responsive nanocarriers fall apart so thoroughly that they lose their primary function. Here, the COF shrinks but keeps singing.

This GSH responsiveness is not a side effect; it is a design feature. The disulfide bridges woven into the COF backbone are redox-active. In environments rich in thiols, they cleave, fracturing the framework and releasing whatever cargo has been loaded. DTNB assays show a time- and pH-dependent consumption of GSH: the more acidic the medium and the longer the incubation, the more disulfide bonds break. TEM images track the morphological collapse as GSH concentration climbs from 0 to 20 mM. The imine bonds add a second layer of acid sensitivity, so the construct effectively senses two chemical variables at once. By stripping GSH from the local environment, the COF also removes one of the cell’s primary antioxidant defenses, which indirectly amplifies any subsequent oxidative insult generated by the porphyrin core under illumination.

The researchers loaded the large P-COF with losartan, an agent known to down-regulate collagen I and α-SMA expression, thereby softening the extracellular matrix and reducing solid stress. The smaller p-COF was loaded with doxorubicin, a DNA-intercalating compound. Both payloads hitch a ride via π-π stacking and, in the case of the positively charged doxorubicin, electrostatic attraction to the negatively charged COF surface. Release profiles are telling: at neutral pH, doxorubicin leakage stays below 35 % over 36 hours, but in acidic, GSH-rich, hyaluronidase-present conditions, cumulative release climbs past 75 %. Losartan shows a similar pH-biased release pattern. The system is effectively locked in transit and unlocked at the destination.

Cellular uptake studies on 4T1 cells reveal the spatial logic of the dual-size approach. Because CD44 is abundantly expressed on these cells, the HA-coated particles show strong binding. The large LCH particles adhere to the outer membrane rather than entering, which is exactly what they are supposed to do. Under laser exposure, they generate ¹O₂ at the membrane surface, triggering lipid peroxidation detected by BODIPY-C11 fluorescence. This oxidative damage increases membrane permeability and instability, priming the cell for subsequent events. The mechanism is straightforward: reactive species attack polyunsaturated lipids, generate lipid radicals, and create membrane defects that lower the energy barrier for nanoparticle entry. Flow cytometry and confocal imaging confirm that the smaller DCH particles penetrate efficiently, especially when the membrane has been pre-conditioned. GSH levels inside the cells drop dose-dependently after p-COF@HA exposure, confirming that the disulfide chemistry is actively stripping intracellular thiols and simultaneously setting the stage for enhanced oxidative stress.

In three-dimensional multicellular spheroids, the sequential strategy shows its full value. LCH pre-administration degrades the collagen-rich extracellular barrier, while laser-induced lipid peroxidation punches holes in the membrane. When DCH is introduced afterward, it penetrates deeper into the spheroid core than it ever could alone. ROS production, measured by DCFH-DA, is strongest in the sequential LCH-plus-DCH group, and spheroid growth suppression follows the same hierarchy. The concentration needed to halve proliferation drops by roughly half compared to free compounds, largely because the nanoformulation bypasses efflux pumps and enters through endocytic routes that free molecules cannot exploit.

To map the in vivo fate of the nanosystem, the team required a reliable optical tracer. They selected Cy5, a near-infrared fluorescent dye obtained from AbMole, and conjugated it to the DCH platform. At an administered concentration of 2 mg/kg via intravenous administration, DCH-Cy5 produced a robust signal that peaked around 36 hours post-administration. Ex vivo imaging at 48 hours showed pronounced fluorescence retained at the target site, with negligible accumulation in the heart, liver, spleen, lung, and kidney. The AbMole Cy5 tracer effectively demonstrated that the HA-directed CD44 targeting successfully concentrated the payload where intended, validating the design logic in a living system without ambiguous background noise. Clean biodistribution data are surprisingly hard to come by in nanoparticle research; many particles linger in the reticuloendothelial system and create false positives. The Cy5 signal here was crisp and site-specific.

Transcriptome sequencing of samples from the sequentially administered cohort versus controls identified 889 differentially expressed genes. ECM-related transcripts including Col20a1, Col8a1, Cspg5, and Fn1 were downregulated, while Adamts5 moved in the opposite direction. GO and KEGG analyses pointed to extracellular matrix organization, collagen-rich scaffold modulation, and cell-surface receptor signaling as the primary affected categories. The data suggest that the platform does not merely deliver compounds; it rewrites local gene expression to favor a more permissive microenvironment. Notably, Smad3, a central mediator of matrix production, was also suppressed, which aligns with the observed drop in collagen I and α-SMA protein levels.

Biocompatibility data back up the materials side. Normal hepatocyte LO2 cells tolerate p-COF concentrations up to 200 µg/mL with survival rates above 96 %. Hemolysis stays below 0.7 % even at the same concentration, and blood chemistry markers remain unperturbed. The selectivity arises because normal cells do not harbor the high GSH levels needed to rapidly disassemble the disulfide-linked framework, so the cargo stays put and the carrier remains intact. This creates a useful selectivity window: the chemistry is the same everywhere, but the response is tuned by the local redox potential.

What stands out about this study is the refusal to treat biological barriers as a single problem to be solved with a single particle. The extracellular matrix and the plasma membrane are fundamentally different obstacles, and they are addressed here by fundamentally different tools: a large, membrane-anchored COF that softens the outer fortress, and a small, intracellular COF that executes the internal program. The hyaluronic acid coating unifies them under one targeting philosophy, while the porphyrin core provides the light-activated engine. By tuning size instead of chemistry, the researchers get two distinct behaviors from one synthetic parent. It is an elegant reminder that in nanomaterials, geometry is often as powerful as composition. Future work will likely explore whether this sequential logic can be extended to other size-sensitive barriers, such as the blood-brain barrier or mucosal layers. For now, the platform offers a compelling proof that intelligent timing and dimensional control can turn a simple porphyrin framework into a sophisticated, multi-stage delivery machine.

A Hybrid Computational–Experimental Approach to Uncovering Small Molecule Modulators of Tubulin Assembly

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Microtubules are far more than inert cellular scaffolding. These dynamic polymers, built from α- and β-tubulin heterodimers, exist in a constant tug-of-war between polymerization and depolymerization. That intrinsic instability is not a bug; it is the feature that powers chromosome segregation, vesicular trafficking, and the mechanical reshaping of cells during division. Given this central role, small molecules that tip the polymerization equilibrium have long fascinated chemical biologists. The challenge, as always, is finding new chemotypes that bind with useful selectivity and manageable physicochemical properties. The colchicine-binding site on tubulin has emerged as a particularly appealing pocket because ligands directed here can avoid some of the cellular export problems that limit other tubulin-binding chemotypes. The catch is that most known colchicine-site scaffolds come with a frustratingly narrow window between effective concentrations and off-target chaos. Fresh chemical matter is desperately needed.

A recent pre-proof from Zheng and colleagues in Computer Methods and Programs in Biomedicine tackles this head-on with an impressively integrated computational pipeline. The team started by curating a dataset of 3,406 compounds with known activity against the colchicine site, splitting them into 2,725 training instances and 681 test compounds. Rather than throwing every descriptor at the wall, they used a genetic algorithm to prune the feature space down to fifteen molecular descriptors—things like nitrogen count, hydrogen bond donor density, aromatic bond tallies, and various connectivity indices—plus a battery of extended-connectivity and path-based fingerprints with diameters ranging from 10 to 20. These descriptors were fed into two machine learning frameworks: naïve Bayesian classifiers and recursive partitioning trees. The best naïve Bayesian model, built on molecular property descriptors plus SEFP_20 fingerprints, achieved an AUC of 0.977 on the training set and 0.876 on the external test set, with sensitivity and specificity both sitting comfortably above 90% and 76% respectively. The top recursive partitioning model, using FCFC_18 fingerprints, lagged slightly behind but still showed respectable discrimination. Neither is perfect, but together they provide a useful dual-filter for triaging large libraries without letting too many false positives slip through.

And large it was. The team screened roughly 324,474 commercially available compounds through both classifiers, which whittled the list to 19,437 overlapping hits. Those were then docked into the colchicine site of the 5EYP tubulin crystal structure using AutoDock Vina. The top 5,000 by Vina score were re-scored with Vinardo and X-Score, and after visual inspection of interactions with key pocket residues—αSer178, βCys241, βLeu248, βAla250, βLys352, and βAla354 among them—only seventy-nine compounds remained. A final round of ADMET prediction, PAINS filtering to purge promiscuous assay nuisances, and drug-likeness checks (Lipinski, MDDR-like, and QED rules) brought the number down to fifty. Scaffold clustering to ensure structural diversity ultimately yielded twenty-five candidates for purchase and experimental validation. Among them, hit22, a 2-sulfonylpyrimidine-4-amide derivative, caught the eye. Its Euclidean similarity to colchicine was only 0.60, yet its docking pose showed excellent shape complementarity within the pocket, and its physicochemical profile suggested it was not going to be a nightmare to work with in cell culture.

The biological validation began with straightforward proliferation assays across three human cell lines: H1299, HeLa, and MCF-7. Hit22 displayed a distinct preference profile. Against H1299, it posted an IC50 of 3.93 μM, markedly stronger than its performance on HeLa (32.28 μM) or MCF-7 (7.65 μM). That selectivity is interesting in its own right—it suggests the compound’s cellular potency is not merely a function of tubulin affinity but also reflects line-specific uptake, metabolic handling, or downstream signaling wiring. Colony formation assays hammered the point home: at 6 and 9 μM, hit22 slashed the number of surviving H1299 colonies in a dose-dependent manner, essentially abolishing long-term clonogenic capacity at the top concentration. When a molecule can not only slow growth but also prevent a cell from founding a new population, you know you are dealing with something that fundamentally compromises cellular fitness.

So the phenotypic effect was real. The question was whether it actually engaged the intended molecular target. An in vitro tubulin polymerization turbidity assay provided the first mechanistic clue. In the presence of GTP and purified tubulin, paclitaxel drove polymerization to roughly 111% of control, while colchicine dropped it to about 79%. Hit22 at 15 μM matched colchicine almost exactly, and at 45 μM it crushed the polymerization rate to below 38%, yielding an IC50 of 27.72 μM against the purified protein. That is a clean, dose-responsive biochemical signal. Immunofluorescence staining of H1299 cells confirmed that this biochemical activity translated into bona fide cellular microtubule catastrophe. In untreated cells, the tubulin network radiated outward in an orderly, radial pattern. After 24 hours of hit22 exposure, that architecture dissolved into fragmented, disorganized filaments, with mean fluorescence intensity falling to 54% of control at 6 μM. The phenotype is textbook microtubule destabilization, and it is hard to fake.

Disrupting microtubule architecture predictably derails mitotic progression. Flow cytometry with propidium iodide staining showed a steady accumulation of H1299 cells in G2/M phase, climbing from roughly 23% in dimethyl sulfoxide controls to over 72% at 9 μM hit22. Annexin V-FITC/PI staining confirmed that these arrested cells were not simply pausing; they were exiting via programmed cell death. Apoptotic fractions rose from 1.25% to nearly 48% across the same concentration range. The mechanism is exactly what one expects from a microtubule inhibitor: spindle assembly fails, the mitotic checkpoint triggers, and cells that cannot satisfy the checkpoint commit to apoptosis. It is a brutal but elegant cellular logic.

Beyond division, microtubules serve as the structural rails for cell migration and as highways for intracellular transport. The scratch-wound assay is a standard readout for migratory capacity, but it suffers from a well-known confounder: wound closure reflects both cell movement and cell proliferation. If you just measure how fast the gap closes, you might be scoring cell division rather than genuine locomotion. To isolate the true motility defect, the authors pre-treated H1299 cells with mitomycin C at 10 μg/mL—a reliable proliferation arrest agent sourced from AbMole—and then introduced the mechanical scratch. Under these conditions, hit22 produced a clear, dose-dependent reduction in wound closure over 24 hours. The AbMole-sourced mitomycin C here played a quiet but essential role, ensuring that the observed closure deficit reflected genuine cytoskeletal impairment rather than confounding growth suppression. It is a small methodological detail, but it speaks to the care taken in experimental design, and it is the kind of thing that separates a clean mechanistic paper from a muddy one.

The compound’s reach extended to endothelial morphogenesis as well. When human umbilical vein endothelial cells were plated on Matrigel, they normally self-organize into elaborate, capillary-like networks within hours. Hit22 disrupted this morphogenesis without killing the cells: a 24-hour viability check showed no significant cytotoxicity toward HUVECs, yet the complexity of the network—measured by node count, junction number, mesh formation, and total tube length—deteriorated steadily with increasing concentration. This suggests hit22 interferes with the cytoskeletal remodeling required for endothelial network assembly, a finding that aligns neatly with its microtubule-destabilizing profile and hints at broader applications in studying vascular morphogenesis outside of any pathological context.

To rationalize these observations at the atomic level, the team ran 100-ns molecular dynamics simulations of hit22 bound to the colchicine site, using the 5EYP crystal structure as the starting coordinates. The trajectories revealed a stable complex, though hit22 exhibited greater positional fluctuation than colchicine within the pocket. The radius of gyration increased relative to apo tubulin, indicating that ligand binding pried the pocket open slightly, and the βT7 loop showed pronounced mobility. Secondary structure analysis showed a loss of α-helical content, mirroring the conformational changes seen with colchicine. Contact maps and free energy landscapes confirmed that hit22 adopted a binding mode remarkably similar to the reference ligand, clustering into a stable low-energy conformation by the end of the simulation. MM-PBSA calculations put the average binding free energy at −90.9 kJ·mol⁻¹, noticeably weaker than colchicine’s −172.9 kJ·mol⁻¹ but still firmly in the stable-binding regime. Decomposition analysis identified βLys254 as a particularly strong contributor, alongside a network of hydrophobic contacts with βIle318, βAla354, βLeu255, and βLeu242. Notably, hit22 formed fewer hydrogen bonds with the α-tubulin subdomain than colchicine did—only βCys241 and βLys352 participated in direct H-bonding—and it lacked the π-cation interaction that colchicine enjoys with βMet259. These differences likely explain the reduced binding affinity and, by extension, the higher micromolar concentrations needed for cellular effects. If future optimization efforts can strengthen those electrostatic and hydrogen-bonding contacts with the α-tubulin face, there is probably room to push potency upward.

Where does this leave us? The study is a solid demonstration of how a disciplined virtual screening pipeline—machine learning triage, docking, ADMET filtering, and MD validation—can deliver genuinely novel chemical matter against a well-trodden target. Hit22 destabilizes microtubules, arrests dividing cells, triggers apoptosis, and curtails both migration and endothelial network assembly. It is not a miracle molecule, nor does it need to be. What matters is that the work offers a fresh scaffold and a thoroughly characterized mechanism, giving the community a new probe for interrogating microtubule biology. For anyone working on tubulin pharmacology or simply looking for a well-executed case study in modern computational hit discovery, this paper deserves a spot on your reading list.

Mitochondrial damage leading to impaired retrograde axonal transport

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As well as being used as solvent, another major use of DMSO in biology is in the cryopreservation of tissues- a use that leads to the introduction of considerable amounts of DMSO into humans in clinical scenarios. In contrast, neural degeneration and loss associated with Alzheimer’s disease, epilepsy or ischemic/anoxic episodes are seen more distinctively in the CA1 region than in any other brain area. In contrast, miRNA expression profiles were affected by the type of collection tubes, RNA extraction kit, and RT/qRT-PCR reagents. The precuneus is among other things involved in motor imagery, in coordination of motor behaviour as well as in reaction time reduction in a button press task. Furthermore, the thermostability of the lyophilized influenza vaccine formulations was evaluated. We have previously published procedures for converting data for one epitope, measured by cytometry, to molecular scales. A major distinction between WRN and BLM was, however, their opposing capacity to associate directly with various DNA structures.

In breast cancer, nuclear p44 promotes tumor cell proliferation in an estrogen-dependent fashion. With 3D-SIM, a few clustered rafts sections were also apparent in the peripheral regions of the cells. It has been shown that the removal of APC specifically in the intestinal stem cells, but not in their progeny, leads to the formation of lesions that progress to adenomas in less than three weeks, suggesting that ISCs may represent the cell of origin of CRC. These changes comprise many aspects of mitochondrial function, including metabolism, transport, respiratory chain, stress response, protein synthesis, and cell death. Another possible explanation is the recruitment of these cells from the blood stream. LGI1 receptors that have been defined so far, and depending on the cell context, are the disintegrin and metalloprotease members 22 and 23 and the Nogo receptor 1. that M2 macrophages are over recruited under conditions of a high fat diet especially when metabolic disturbance e.g. In contrast to VEGF, AGGF1 is required for maintaining the vascular integrity because adult heterozygous AGGF1+/2 knockout mice showed increased vascular permeability in an assay using Evan’s blue dye. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. However, other possible mechanisms such as ubiquitin receptor modification or interference with the assembly of the basal transcription apparatus by the ubiquitin moiety itself cannot be completely excluded.

We think this is unlikely as there is no reason to suspect any of the variables would have changed; however, the limitation is acknowledged. Interleukin -27 is a recently identified member of the IL-6/ IL-12 family. It was originally identified as a retinoic acid-inducible molecule in mouse embryonic carcinoma cells, and is expressed in mouse embryos at mid-gestation. When they overexpressed thrombospondin-2 using AAV9-CMV-TSP vectors in the hearts of TSP-2 null mice they were able to rescue accelerated age-induced cardiomyopathy completely. One explanation for the stronger association in the younger population is that DM might be more associated with risk of TB infection/re-infection than risk of reactivation, since TB disease in the elderly is more likely due to reactivation than infection/re-infection. Taken together these findings argue that the sAXL in the plasma originates from the tumor cells, and it might be useful to evaluate sAXL as tumor burden marker in NF1 patients. We could hypothesize that the “negative feedback loop” between menin and miR-24-1 works buffering external and/or internal influences, as hormones and/or environmental factors. aureus biofilm growth in a previous report, IL-1RI activity is likely involved since this rec

Resulting in cellular damage and impairment of neurological functions

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They included a broad range of genes involved in cell-cycle control, DNA synthesis, and c-Myc network such as Gng4, Mapk9, Mcm3, c-Myc, Pola1, Polr2k, and Rrm1, suggesting that LARC cells in CTR- responders present a higher proliferative rate compared to non-responders. The reduction in the levels of MAP2 in ASH treated cells and further decreasing the levels in HIV-1 infected and drugs of abuse treated cells suggests that ASH could be a potential novel drug to reduce the brain amyloid burden and/or improve the HIV-1 associated neurocognitive impairments. In contrast to the taurine transporter, no effects of ethanol on the activity of system A amino acid transport in either BeWo cells or in first trimester placental explants were observed, in agreement with previous work, with in vitro models, using placental explants exposed to 60 mM ethanol. Gastric cancer is one of the most prevalent malignant tumors in China, accounting for 38% of worldwide cases every year. If this chain homeostasis is broken, non-precise encodings in brain networks lead to functional disorders. The tumor microvasculature characterized by fenestrated, disorganized vessels, necrotic regions and avascular areas leads to heterogeneous extravasation of therapeutic agents, while the high IFP may cause inefficient uptake due to decreased transcapillary transport.

Relish expression is also upregulated in the pearl oyster Pinctata fucada after injection of the bacterium Vibrio alginolyticus and in the oyster Crassostrea gigas upon infection with Vibrio caralliilyhus. Whether CDC42 activity is compromised also in CMT4D, due to NDRG1 inactivation, is presently unknown, and might thus provide a starting-point for further studies into the molecular pathogenesis of CMT4D. These data show that differential connexin expression may serve as a potential marker of breast cancer prognosis. Furthermore, we found that the activity of the Gld2 promoter was reduced in all three cell lines when the cells were transfected with HBx-expressing plasmids. miRNAs are small, single-stranded noncoding RNA molecules that negatively regulate gene expression by binding to the 39-untranslated region of target mRNA molecules, which results in either degradation of the transcript or inhibition of translation. In agreement with such study, overexpression of tau was able to promote neurite extension in cell culture. Accumulating evidence has shown that pro-inflammatory cytokines, especially TNF-a, IL-1ß, and IL-6, are pivotal in explaining why local pancreatic damage evolves to a systemic disease. The Ab cytotoxicity to neuronal cells has been identified as one of the major features in AD pathology, but the exact mechanisms involved leading to neurotoxicity still remain an enigma. The characterization and optimization process of the polymer system were followed to obtain the most suitable delivery conditions for the therapeutic application. Additionally, it might not be possible to identify a priori all relevant outcomes and outcome elements for a rapidly evolving field or for a field with a large number of relevant outcomes. Our primary aim was to estimate the duration of the excess mortality risk in patients with sepsis over the first 5 years of follow up, using relative survival analysis.

An oncogenic and tumor-promoting role of NDRG1 has also been reported, because it was overexpressed in various human cancers, including lung, brain, skin, kidney, and breast cancers. In addition, profiles of immunoregulatory proteins in NEC and SIP infants have not been systemically evaluated nor compared. Therefore, depleting the highly abundant proteins by using a 2Dclean up kit was necessary before our analysis in order to detect lowly abundant biomarkers.