Search Results (2,483)

High Mobility Group ^{Box 1} (HMGB1) is a central pro-inflammatory mediator released from damaged or stressed cells, where it activates receptors such as the Receptor for Advanced Glycation Endproducts (RAGE). Dendritic polyglycerol sulfate (dPGS), a hyperbranched polyanionic polymer, is known for its anti-inflammatory activity. In this study, we examined how dPGS modulates HMGB1-driven signaling in RAW 264.7 macrophages and human microglia. Recombinant human HMGB1 expressed in Escherichia coli (E. coli) was purified by nickel-nitrilotriacetic acid (Ni-NTA) and heparin chromatography. Proximity ligation assays (PLA) revealed that dPGS significantly disrupted HMGB1/RAGE interactions, particularly under lipopolysaccharide (LPS) stimulation, thereby reducing inflammatory signaling complex formation. This correlated with reduced activation of the nuclear factor kappa B (NF-κB) pathway, demonstrated by decreased nuclear translocation and transcriptional activity. Reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time PCR (RT-qPCR) showed that dPGS suppressed HMGB1- and LPS-induced transcription of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). Enzyme-linked immunosorbent assay (ELISA) and Griess assays confirmed reduced TNF-α secretion and nitric oxide production. Electron paramagnetic resonance (EPR) spectroscopy further showed that dPGS altered HMGB1/soluble RAGE (sRAGE) complex dynamics, providing mechanistic insight into its receptor-disruptive action. Full article

Neuromast cells are specialized mechanosensory receptor cells embedded within the lateral line system of aquatic vertebrates, enabling the detection of water movement and vibration that are essential for navigation, prey capture, and predator avoidance. These cells share common evolutionary and functional homology with mammalian inner ear hair cells, both of which rely on stereocilia-mediated mechano-transduction and ion channel activation to convert mechanical stimuli into neural signals. Unlike their mammalian counterparts, neuromast hair cells possess a regenerative capacity following damage, making the lateral line system a unique model for studying hair cell regeneration and sensory restoration. This study examines the potential of the Mexican tetra (Astyanax mexicanus) as a novel model organism for investigating ototoxicity and regeneration of neurosensory hair cells. Here, we explore the cranial and trunk lateral line neuromasts, including deep canal neuromast cells located in facial bones, such as the mandible and circumorbital bones. In the present study, juvenile surface-dwelling Mexican tetra were exposed to a 500 µM neomycin for 4 h to induce targeted hair cell damage. The samples were collected at 4-, 12-, 24-, and 72 h post-exposure. Furthermore, neuromast cell viability was assessed using [2-(4-(Dimethylamino) styryl)-N-ethylpyridinium iodide] (DASPEI). Gene expression analysis revealed a modest increase in Fibroblast Growth Factor 1 (fgf1) and Axis Inhibition Protein 2 (axin2) expression following treatment; however, these changes were not statistically significant. The SRY-box transcription factor 2 (sox2) remains constant throughout the exposure and recovery period. These findings highlighted the regenerative dynamics of neuromast cells in Mexican tetra. This work lays the foundation for future therapeutic strategies targeting human sensory deficits, particularly those involving inner ear hair cell degeneration. Full article

Background: The interaction between the endocannabinoid system (ECS), specifically the CB1 and CB2 cannabinoid receptors, and neuropathy has aroused great research interest due to the possible implications for treatment. Complications following type 1 diabetes, due to impaired glucose metabolism and chronic inflammation, may benefit from targeted therapeutic strategies involving the ECS. This study explores the effects of photobiomodulation therapy (PBMT) on streptozotocin (STZ)-induced diabetic peripheral neuropathy (DPN) in rats. The study assessed body mass, hyperglycemia, mechanical hyperalgesia, and the influence of PBMT on these conditions over four weeks. Results showed that while PBMT did not alter the metabolic aspects of type I diabetes, it significantly reduced mechanical hyperalgesia compared to untreated diabetic neuropathic rats. Notably, cannabinoid receptor antagonists for CB1 and CB2 elicited a transient reversal of this antihyperalgesic effect, indicating a potential role of these receptors in PBMT’s mechanism. However, CB2 modulation was not statistically significant, whereas changes in CB1 receptor expression were observed in the dorsal root ganglia, suggesting its involvement in PBMT’s effects. These findings highlight the importance of CB1 and CB2 receptors in DPN and suggest that PBMT may offer a therapeutic benefit by mitigating mechanical hyperalgesia. Further investigation into cannabinoid receptor dynamics in diabetes could help in new therapeutic strategies for managing diabetic complications. Full article

Cutaneous T-Cell Lymphomas (CTCL) are a heterogenous group of T-cell malignancies in the skin and have poor treatment outcomes in advanced stages. CD5, a surface glycoprotein expressed on most mature T cells, has emerged as a promising target for chimeric antigen receptor (CAR) T-cell therapy in systemic T-cell lymphomas. However, its expression profile in CTCL and relevance for targeted therapy remain unclear. Notably, in CTCL, the cell surface expression of receptors, such as CD7 and CD26, tends to become downregulated on the surfaces of malignant T cells In this study, we analyzed single-cell RNA sequencing (scRNA-seq) data from patients at two institutions with mycosis fungoides (MF), the most common subtype of CTCL with a predominantly CD4 phenotype. We utilized 5 patch/plaque MF skin biopsies (majority from early-stage patients), 8 MF tumor biopsies (all from advanced-stage patients), and 8 healthy control biopsies to evaluate lesion-specific CD5 gene expression on CD4 T cells. We found that CD5 was significantly increased in malignant MF CD4 T cells compared to healthy control CD4 T cells (21.1% of MF CD4 T cells expressed CD5 vs. 5.2% of healthy control CD4 T cells, respectively). In subgroup analysis, patch/plaque stage MF biopsies showed higher expression of CD5 in CD4 T cells than tumor stage MF biopsies. Notably, 94.3% of malignant CD4⁺ T cells in tumor stage MF lesions exhibited complete CD5 loss compared to only 76.6% in patch-plaque MF lesions, suggesting antigen escape in tumor stage disease. These findings demonstrate that CD5 expression in CTCL is dynamic and varies based on lesion type. Our work suggests CD5 may be a viable therapeutic target in MF with patch/plaque presentations but may not be as effective in advanced stages of MF with tumor presentations. This work informs CD5 gene expression in MF based on clinical lesion type and further information is needed to clarify clinical implications as a future therapeutic target. Full article

Breast cancer remains a major global health challenge. In 2022, there were an estimated 2.3 million new cases and 670,000 deaths among women worldwide. Hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2−) breast cancer accounts for approximately 70% of breast cancer diagnoses. The treatment landscape for advanced HR+)/HER2− breast cancer has been transformed by the introduction of CDK4/6 inhibitors in the first-line setting. However, therapeutic strategies following progression on CDK4/6 inhibitors remain heterogeneous and uncertainty exists in their optimal integration in clinical practice. This review aims to systematically examine available second-line and subsequent treatment options for HR+/HER2− metastatic breast cancer after progression on CDK4/6 inhibitors, with a focus on biomarker-driven strategies and emerging therapies. The therapeutic landscape beyond CDK4/6 inhibitors includes targeted agents guided by actionable biomarkers as well as novel selective estrogen receptor degraders (SERDs). In biomarker-unselected populations, options include CDK4/6 continuation strategies, endocrine monotherapy in selected cases, and cytotoxic therapy. The integration of molecular testing via next-generation sequencing has become standard of care in guiding these decisions. However, overlapping molecular alterations and a lack of consensus on treatment sequencing pose significant challenges. Prognostic factors such as circulating tumor DNA dynamics may further refine treatment personalization. Post-CDK4/6 therapy in HR+/HER2− metastatic breast cancer is an evolving and increasingly complex area of practice. Optimal treatment selection should be tailored to both tumor biology and patient-specific factors, supported by molecular testing and high-quality evidence. Full article

Cell migration through confined spaces is a critical step in cancer metastasis, yet the spatial regulation of endocytosis and adhesion dynamics during this process remains poorly understood. To investigate this, we adapted a microfluidic platform that generates stable, spatially linear biochemical gradients across 5 μm-tall migration channels. COMSOL simulations and optical calibration using FITC-dextran confirmed that gradients form reliably within 5 min. The microdevice also supports long-term live imaging and is compatible with both spinning disk confocal and total internal reflection fluorescence structured illumination microscopy modalities, enabling high-resolution visualization of adhesion and endocytic structures. By leveraging this platform for spatially restricted drug delivery, we locally applied the endocytic inhibitor Dyngo-4a to either the front or rear of migrating cells. This revealed that front-targeted endocytic inhibition preserved or increased leading-edge enrichment of paxillin and the clathrin adaptor AP-2, whereas rear-targeted inhibition eliminated paxillin polarity and reduced AP-2 polarity. These changes were accompanied by a significant increase in cell migration speed under front-targeted inhibition, while rear-targeted inhibition had no significant effect on speed and neither treatment altered persistence. Together, these findings suggest that endocytic polarity regulates adhesion dynamics and cell migration under confinement, offering a mechanistic insight into processes relevant to cancer cell invasion. Full article

Breast cancer is the most prevalent cancer in women worldwide and presents a major therapeutic challenge, particularly triple-negative breast cancer (TNBC), a subtype characterized by an aggressive clinical course but heightened sensitivity to chemotherapy. Natural products, such as triterpene glycosides derived from sea cucumbers, have emerged as promising candidates with high anticancer potential against TNBC. This study investigated the pathways of anticancer action of cucumarioside A₀-1 (Cuc A₀-1) and djakonovioside A (Dj A), isolated from the sea cucumber Cucumaria djakonovi, triggered and regulated in MDA-MB-231 cells (triple-negative breast cancer cell line). We employed functional assays (cAMP level, Ca²⁺ influx, control of cell proliferation and colony formation), Western blotting for mitogen-activated protein kinase MAPK) signaling, and in silico molecular docking. A_2B adenosine receptor (A_2BAR) was identified as a novel target for both glycosides. As antagonists, they reduced cAMP production and inhibited NECA (5-(N-ethylcarboxamido)adenosine)-induced Ca²⁺ influx. This A_2BAR blockade suppressed the MAPK pathway, profoundly inhibiting phospho-ERK1/2, p38, and JNK1/2, which led to the activation of the intrinsic apoptotic pathway and strong inhibition of cell proliferation and colony formation. Surprisingly, co-treatment with the NECA agonist enhanced the antiproliferative effects of the glycosides. It was supposed that the interaction of glycosides with the NECA-preactivated receptor may bias signaling toward the Gi and Gq/PLC/ERK1/2 pathways, underscoring the central role of the MAPK pathway in controlling cell growth. Molecular docking confirmed binding to the A_2BAR orthosteric site, revealing that Cuc A₀-1 and Dj A employ distinct interaction modes. To our knowledge, this is the first report to define A_2BAR as a target for sea cucumber glycosides. Their potent antitumor effects, mediated through the antagonism of A_2BAR and subsequent MAPK pathway inhibition, position them as promising lead compounds for cancer types with high expression A_2BAR. Full article

Protein–protein docking is a cornerstone of computational structural biology, yet its reliability for large, multimeric assemblies remains uncertain. Standard workflows typically include geometry optimization or molecular dynamics equilibration to relieve local strains and improve input quality, but the extent to which these preparatory steps alter docking outcomes has not been systematically evaluated. Here, we address this question using the mitochondrial chaperonin Hsp60, a dynamic double-ring complex essential for protein folding, and MIX, a kinetoplastid-specific protein with unresolved function, as a stress test system. By comparing docking predictions across minimized, equilibrated, and ensemble-refined structures of Hsp60 in three conformational states (apo, ATP-bound, and ATP–Hsp10), we show that structural relaxation profoundly reshapes the docking landscape. Minimization alone often yielded favorable scores but localized binding, while longer MD trajectories exposed alternative sites, including central cavity, equatorial ATP pocket, and apical domain, each consistent with distinct regulatory hypotheses. These findings reveal that docking outcomes are highly sensitive to receptor preparation, especially in complexes undergoing large conformational transitions. More broadly, our study highlights an underappreciated vulnerability of docking pipelines and calls for ensemble-based and dynamics-aware approaches when predicting interactions in large biomolecular machines. Full article

Mitochondrial dynamics are important for cellular health and include morphology, fusion, fission, vesicle formation, transport and contact formation with other organelles. Myosin XIX (Myo19) is an actin-based motor, which competes with TRAK1/2 adaptors of microtubule-based motors for binding to the outer mitochondrial membrane receptors Mitochondrial Rho GTPases 1/2 (Miro). Currently, it is poorly understood how Myo19 contributes to mitochondrial dynamics. Here, we report on a Myo19-deficient mouse model and the ultrastructure of the mitochondria from cells of Myo19-deficient mice and HEK cells, Miro-deficient HEK cells and TRAK1-deficient HAP1 cells. Myo19-deficient mitochondria in MEFs and HEK cells have morphological alterations in the inner mitochondrial membrane with reduced numbers of malformed cristae. In addition, mitochondria in Myo19-deficient cells showed fewer ER–mitochondria contact sites (ERMCSs). In accordance with the ultrastructural observations, Myo19-deficient MEFs had lower oxygen consumption rates and a reduced abundance of OXPHOS supercomplexes. The simultaneous loss of Miro1 and Miro 2 led to a comparable mitochondria phenotype and reduced ERMCSs as observed upon the loss of Myo19. However, the loss of TRAK1 caused only a reduction in the number of cristae, but not ERMCSs. These results demonstrate that both actin- and microtubule-based motors regulate cristae formation, but only Myo19 and its membrane receptor Miro regulate ERMCSs. Full article

Heat stress typically suppresses systemic immunity in fish; however, its effects on the brain—an organ traditionally regarded as immune-privileged—remain unclear. In this study, we performed histopathological examination and RNA-seq analysis on the brains of juvenile largemouth bass (Micropterus salmoides) exposed to control (28 °C) and elevated (36.5 °C) water temperatures for 8 weeks. Histological analysis revealed distinct cytoarchitectural and pathological changes in specific brain regions. RNA-seq analysis identified a total of 1240 differentially expressed genes, with 22 heat shock protein genes notably showing significant up-regulation. The immune system-associated genes emerged as the most prominently affected category. Gene set enrichment analysis (GSEA) based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotations revealed that up-regulated genes were enriched in immunity-related pathways, including the NOD-like receptor (NLR) signaling pathway, Toll-like receptor (TLR) signaling pathway, and cytosolic DNA-sensing pathway. Additionally, the levels of apoptosis and necroptosis were moderately increased. GSEA based on Gene Ontology (GO) terms indicated that down-regulated genes were primarily associated with cell division. Protein–protein interaction (PPI) and clustering analysis identified 41 core genes in the top three clusters, encompassing those related to nuclear chromosome segregation, ribosome biogenesis, and stress response. The inhibition of genes involved in nuclear chromosome segregation may disrupt cellular homeostasis by significantly impairing microtubule dynamics. In contrast, genes associated with ribosome biogenesis and stress response were up-regulated, which could counteract the adverse effects caused by long-term heat stress. We propose that brain-specific immune activation, particularly via the NLR and TLR signaling pathways, acts as a compensatory strategy to counterbalance heat-induced cell death, thereby revealing a novel neuro-immune adaptation axis. Full article

Background/Objectives: The cannabinoid type 2 receptor (CB₂ receptor) has been extensively studied in recent years due to the benefits associated with its modulation, including the regulation of the inflammatory response, neuroimmunomodulatory properties, and antitumor effects, all with the advantage of lacking significant psychoactive effects. Herein, we report the design, synthesis, characterization, biological assays, and molecular modelling analyses of novel (5/6-chloro-2-aryl-1H-benzo [d]imidazol-1-yl)(4-methoxyphenyl)methanone and 5/6-chloro-1-(4-methoxybenzyl)-2-aryl-1H-benzo [d]imidazole regioisomers as potential cannabinoid type 2 receptor ligands. Methods: The compounds were evaluated for their presumed CB₂ agonist activity using an indirect receptor-dependent apoptotic cell death assay exerted by cannabinoids, using the cell lines HEK293 (low CB₁/CB₂ expression), U-87 MG (high CB₁ expression), and HL-60 (exclusive CB₂ expression), and including the known cannabinoid ligands WIN-55,212-2 and AM630 as reference ligands. Flow cytometry was performed to assess apoptosis. Molecular docking and molecular dynamics simulations were used to explore ligand-receptor interactions at the CB₂ active site. Results: Compounds 3a, 3b’, 3c, and 4b selectively reduced HL-60 cell viability, similar to WIN-55,212-2, while showing no toxicity toward HEK293 or U-87 MG cells. Flow cytometry indicated that compounds 3a and 3c induced apoptosis in HL-60 cells comparable to WIN-55,212-2. Computational studies suggested that both compounds bind within the CB₂ receptor active site predominantly through π–π and hydrophobic interactions involving their benzo [d]imidazole cores, 2-aryl moieties, and 4-methoxybenzoyl scaffolds, resembling the binding patterns of established CB₂ ligands. Conclusions: Compounds 3a and 3c exert selective cytotoxicity against HL-60 cells, likely via a CB₂ agonist-mediated apoptotic mechanism. The applied combined experimental and computational approach provides a rapid, informative strategy for preliminary evaluation of CB₂ ligands and guides subsequent detailed pharmacological studies. Full article

Glaucoma represents a social and economic burden due to both its increasing incidence and the lack of knowledge about its physiopathology and treatment strategies. The main factor hindering progress in glaucoma research is the disease’s heterogeneity, which depends on both genetic and environmental factors. This limitation directly affects glaucoma research, posing obstacles to the elucidation of risk factors, disease mechanisms, and treatment strategies. Therefore, the need emerges to integrate pre-clinical experimental observations from different experimental models to recapitulate different aspects of the disease and achieve a successful translation to clinics. Here, we reviewed the glaucoma models that are currently available for basic and translational research, with a specific focus on models based on rodents. Regarding genetic glaucoma models, we considered the main hallmarks and limitations of DBA/2J, glutamate/aspartate transporter/excitatory amino acid carrier 1, myocilin, connective tissue growth factor, optineurin, purinergic receptor 2Y, caveolin 1, and endothelin-1 mice. Regarding other glaucoma models, we considered rodent models based on intraocular pressure elevation via perturbation of aqueous humor dynamics or on direct degeneration of retinal ganglion cells via physical or chemical damage. Full article

Background: In this research work, novel pyrazolone-derived oxadiazole-based benzamide derivatives (1–10) were synthesized through unique and facile synthetic routes. Introduction: These scaffolds were designed to be therapeutically more effective and have fewer side effects. Methods: To confirm the structure of analogs in detail, we employed ¹HNMR, ¹³CNMR, and HREI-MS spectroscopy. The potential of all derivatives was tested by screening them against alpha-amylase and alpha-glucosidase in comparison with reference anti-diabetic drug acarbose (4.50 ± 0.20 µM and 4.90 ± 0.30 µM). Results & Discussion: Among all tested analogs and standard drugs, derivative 3 proved to be the most promising candidate. It exhibited the most powerful inhibitory effect (IC₅₀ = 3.20 ± 0.20 µM and 3.60 ± 0.10 µM). To further investigate its activity, the experimental results were supported by in silico investigations. Molecular docking demonstrated strong and viable interactions between enzymes and the most potent compound. DFT calculations validated the electronic configuration, stability, and reactivity of lead molecules. Furthermore, the ADMET profile predicted the favorable drug likeness properties and low toxicity. The results of docking were further confirmed via molecular dynamics analysis, whereas the pharmacophore model of analog 3 supports the formation of a stable hydrogen bond network of derivatives with the receptor site of the enzyme. Conclusions: Collectively in silico and in vitro results underscore the therapeutic potential of these derivatives for the effective treatment of diabetes in the future. Full article

Background: The interleukin-10 (IL-10) signaling system, comprising ligands (IL-10s) and receptors (IL-10Rs), plays critical roles in immune regulation, inflammation resolution, and disease pathogenesis. “IL-10 signaling system” here refers to the immunomodulatory signaling system composed of ligands (IL-10s) and receptors (IL-10Rs), which belong to different Protein families in evolution, but achieve functional synergy through the conserved JAK-STAT pathway. Understanding their evolutionary and functional dynamics is essential for elucidating immune mechanisms and therapeutic targeting. Methods: Through phylogenetic reconstruction, homology analysis, and sequence alignment across >400 animal species, we traced the evolutionary trajectory and structural–functional diversification of IL-10s and IL-10Rs. Results and Conclusions: IL-10 signaling components emerged in early vertebrates, with IL-10Rs originating in cartilaginous fishes (~450 Mya) and IL-10s diversifying in bony fishes (~400 Mya). Functional divergence yielded immunosuppressive (IL-10), barrier-protective (IL-20 subfamily), and antiviral (type III IFN) subgroups. Structurally, conserved motifs (e.g., IL-10R1 GYXXQ, IL-22 N54-glycosylation) underpin receptor–ligand binding and JAK/STAT signaling. Evolutionarily invariant residues suggest candidate therapeutic epitopes. This study provides an evolutionary framework highlighting functional conservation and species-specific adaptation within IL-10 signaling, with implications for immunotherapy and animal breeding. Full article

It is well-known that EGF binding to EGFR stimulates signal transduction and endocytosis, with the latter leading to lysosomal degradation of EGFR. However, the majority of data on the regulation of endocytosis have been obtained in tumor-derived cells. Here, we perform a comprehensive analysis of the role of endolysosome acidification in the regulation of endocytic pathway in tumor cells and in endometrial MSCs as a model of proliferating, undifferentiated, non-immortalized cells. Using QD-labeled EGF, the dynamics of co-localization of EGF-receptor complexes with endocytic markers in the control and upon inhibition of V-ATPase by Bafilomycin A1 (BafA1) were studied using confocal microscopy. Image analysis showed that in HeLa and A549 cells, BafA1 significantly slowed down EGFR entry into and exit from EEA1-positive early endosomes without disrupting passage through Rab7, CD63, and Lamp1 compartments, but rather shifting it to later times. In enMSCs, only a portion of EGF-containing endosomes entered the degradation pathway, and lysosomal delivery was significantly delayed. Unlike HeLa, in enMSC early endosomes, BafA1 increased the association of EGF-QDs with EEA1, suggesting a lower pH level, which is suboptimal for EEA1-dependent fusions. It is concluded that, unlike HeLa, enMSCs form a population of pH-independent endosomes containing activated EGFR for a long time. Full article