Search Results (11,279)

Inflammatory bowel disease (IBD) is a chronic immune-mediated condition of the gastrointestinal tract, characterized by dysregulated inflammatory responses throughout the gastrointestinal tract. It includes two major phenotypes, Crohn’s disease (CD) and ulcerative colitis (UC), which present with varying gastrointestinal and systemic symptoms. The pathophysiology of IBD is multifactorial including genetic predisposition, mucosal and epithelial dysfunction, environmental injury, and both innate and adaptive immune response abnormalities. Several predisposing genetic factors have been associated with IBD explaining the strong hereditary risk for both CD and UC. For example, Caspase Recruitment Domain 9 (CARD9) variant rs10781499 increases risk for IBD, while other variants are specific to either CD or UC. CD is related to loss-of-function mutations in the nucleotide oligomerization domain containing the protein 2 (NOD2) gene and Autophagy-Related 16-like 1 (ATG16L1) gene. UC risk is increased particularly in Chinese populations by the A-1661G polymorphism of the Cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene. This abnormal CTLA-4 interferes with B- and T-cell responses causing predisposition to autoimmune conditions. Previous studies suggested that IBD results from breakdown of the adaptive immune system, primarily of T-cells. However, new evidence suggests that a primary breakdown of the innate immune system in both CD and UC increases susceptibility to invasion by viruses and bacteria, with a compensatory overactivation of the adaptive immune system as a result. When this viral and microbial invasion continues, further damage is incurred, resulting in a downward cycle of further cytokine activation and epithelial damage. Released biomarkers also affect the permeability of the epithelial membrane, including lactoferrin, nitric oxide (NO), myeloperoxidase (MPO) and its activation of hypochlorous acid, matrix metalloproteinases (MMPs), especially MMP-9, omentin-1, and others. Increased macrophage and dendritic cell dysfunction, increased neutrophil activity, increased numbers of innate lymphoid cells, increased T-cells with decreased regulatory T-cells (Tregs), and changes in B-cell populations and immunoglobulin (Ig) functions are all associated with IBD. Finally, treatment of IBD has typically consisted of medical management (e.g., aminosalicylates and corticosteroids) and lifestyle modification, and surgical intervention in extreme cases. New classes of medications with more favorable side effect profiles include anti-integrin antibodies, vedolizumab, etrolizumab, and carotegrast methyl. Additionally, fecal microbiota transplant (FMT) is a newer area of research for treatment of IBD along with TNF-blockers, JAK inhibitors, and S1PR modulators. However, expense and long preparation time have limited the usefulness of FMT. Full article

27-Hydroxycholesterol (27OHChol), a cholesterol metabolite, induces inflammatory responses in monocytic cells and promotes their differentiation into mature dendritic cells. Here, we examined whether inhibition of heat shock protein 90 (HSP90) modulates these responses. Treatment with ganetespib, a selective HSP90 inhibitor, significantly reduced chemokine CCL2 expression, lowering monocytic cell migration. It also suppressed matrix metalloproteinase-9 (MMP-9) expression and attenuated the lipopolysaccharide (LPS) response otherwise amplified by 27OHChol. Furthermore, ganetespib decreased mature dendritic cell markers (CD80, CD83, CD88) and restored endocytic activity, indicating a less activated state. These changes suggest that HSP90 regulates 27OHChol-induced pro-inflammatory activation via its client proteins. To explore this mechanism, we examined the phosphorylation status of signaling proteins. 27OHChol enhanced phosphorylation of Akt and its downstream targets, S6 and 4E-BP1 within the Akt/mTORC1 pathway. Ganetespib reduced total and phosphorylated Akt and 4E-BP1, and selectively inhibited S6 phosphorylation without altering total protein level. Collectively, these findings demonstrate that HSP90 inhibition by ganetespib mitigates 27OHChol-driven monocytic cell activation through suppression of the HSP90-Akt/mTORC1 axis. Targeting this pathway may provide a promising therapeutic strategy for metabolic inflammation associated with oxysterols. Full article

The antibacterial properties of Ag(I) coordination compounds are well documented; however, their effectiveness is highly dependent on the choice of appropriate ligands, and it is frequently hindered by their low water solubility and limited bioavailability. Herein, six new Ag(I) complexes incorporating the quinazolinone thioamide mqztH (=2-mercapto-4(3H)-quinazolinone) and phosphine co-ligands were synthesized and investigated for their antibacterial activity. In vitro activity assays against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacterial strains revealed that all complexes selectively inhibited S. aureus bacterial growth. Structure–activity relationship analysis showed that monodentate PPh₃ co-ligands play a key role in enhancing the antibacterial efficacy of their complexes. Notably, complex [AgCl(mqztH)(PPh₃)₂] (1) exhibited broad-spectrum activity, with IC₅₀ values of 4.2 ± 1.4 μg mL^–1 (4.9 μΜ) for S. aureus and 63 ± 1.9 μg mL^–1 (75 μΜ) for E. coli bacteria. To improve solubility and antibacterial activity, complex 1 was encapsulated in barium alginate (BaAlg) matrices to form hydrogel-based drug delivery formulations [¹]@BaAlg. The synthesized formulations retained the bactericidal effect of the complex, achieving comparable activity at concentrations lower by an order of magnitude compared to complex 1 in free form. Combined with the demonstrated high biocompatibility of complex 1 toward L929 normal eukaryotic cells, as well as the biocompatible nature of the alginate matrix, these findings underscore the strong potential of the complex 1-loaded hydrogel formulations for further investigation and development as effective antibacterial drug platforms. Mechanistic studies confirmed the redox-active nature of complex 1 and its potential to inhibit the function of glutathione reductase (GR) and thioredoxin reductase (TrxR) at low concentrations, suggesting the interference with bacterial redox homeostasis as a relevant mechanism of bioactivity. Full article

Clay minerals and other flocculants are used to mitigate the effects of some species that produce harmful algal blooms due to their physical and chemical characteristics. In this study, we applied calcium bentonite clay (Bca) and zeolite (Ze) to flocculate and remove cells of the dinoflagellate Gymnodinium catenatum (Graham), a producer of paralyzing toxins. The flocculants were characterized by scanning electron microscopy (SEM) in combination with an energy-dispersive X-ray spectroscopy (EDS) microanalysis system. During experiments, Bca and Ze were suspended in distilled water, deionized water, and seawater at concentrations of 0.25, 0.5, 1.0, 1.5, 2.0, 2.5, and 4.0 gL⁻¹. The percentage of removal efficiency (RE%) of biomass indicators of G. catenatum was calculated. The cell number and concentration of chlorophyll a and peridinin were analyzed using high-performance liquid chromatography (HPLC-UV and HPLC-DAD). The external effects on cells of G. catenatum were recorded. As a result, the maximum RE% of Bca was 79% with respect to the total number of cells, chlorophyll a was 69% and peridinin of 73%. The RE% of Ze was less than 40%. In the matrix of sedimented Bca, malformation of cells was observed, inhibiting their swimming, as well as death and rupture of cells with temporary cyst formation after 72 h. We conclude that Bca, suspended in deionized and distilled water, was more efficient in flocculating cells of G. catenatum. Full article

Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) that influence cancer progression via extracellular matrix (ECM) remodeling and secretion of growth factors and cytokines. Endothelial-to-mesenchymal transition (EndMT) is emerging as an important axis among the heterogeneous origins of CAFs. This review introduces the diverse methods used to induce EndMT in cancer—mouse tumor models, conditioned-medium treatment, co-culture, targeted gene perturbation, ligand stimulation, exosome exposure, irradiation, viral infection, and three-dimensional (3D) culture systems—and summarizes EndMT cell-type evidence uncovered using transcriptomic and proteomic technologies. Hallmark EndMT features include spindle-like morphology, increased motility, impaired angiogenesis and barrier function, decreased endothelial markers (CD31, VE-cadherin), and increased mesenchymal markers (α-SMA, FN1). Reported mechanisms include signaling via TGF-β, cytoskeletal/mechanical stress, reactive oxygen species, osteopontin, PAI-1, IL-1β, GSK-3β, HSP90α, Tie1, TNF-α, HSBP1, and NOTCH. Cancer-induced EndMT affects tumors and surrounding TME—promoting tumor growth and metastasis, expanding cancer stem cell-like cells, driving macrophage differentiation, and redistributing pericytes—and is closely associated with poor survival and therapy resistance. Finally, we indicate each study’s stance: some frame cancer-induced EndMT as a source of CAFs, whereas others, from an endothelial perspective, emphasize barrier weakening and promotion of metastasis. Full article

Intervertebral disc degeneration is a leading contributor to chronic back pain and disability worldwide. This review comprehensively explores the complex interplay of cellular, molecular, and biomechanical alterations within the disc microenvironment that underlie intervertebral disc degeneration pathophysiology. Emphasis is placed on extracellular matrix degradation, cellular senescence, inflammation, oxidative stress, angiogenesis, and multiple forms of programmed cell death including apoptosis, pyroptosis, and ferroptosis. An in-depth analysis of key signaling pathways and regulatory molecules illustrates how these processes disrupt homeostasis and drive disease progression. Additionally, the review highlights emerging therapeutic approaches aimed at modifying the disc microenvironment, including mesenchymal and notochordal cell-based therapies, senolytics, ferroptosis inhibitors, gene therapy, and biomaterial innovations such as hydrogels, scaffolds, and nanocarriers. These strategies target degenerative cascades at the molecular level and represent a shift toward regenerative and disease-modifying interventions. While several approaches show promise in preclinical and early clinical studies, challenges related to safety, delivery, and long-term efficacy remain. This review underscores the importance of integrating molecular insights with translational innovations to develop targeted therapies for intervertebral disc degeneration and guide future research efforts. Full article

The extracellular matrix (ECM) supports spermatogonial stem cell (SSC) function by mimicking biochemical and structural features of the native niche. However, optimal feeder systems and ECM materials remain key limitations in porcine SSC (pSSC) cultures. We developed a porcine-derived ECM (pECM) from porcine feet and evaluated its effectiveness in supporting pSSC maintenance and proliferation under feeder-dependent conditions. We examined protein molecular weight distribution and pECM extract composition. Surface characterization was performed using scanning electron microscopy and atomic force microscopy. We compared pECM with conventional coatings, including gelatin and non-coated controls, using morphological analysis, WST-1 assay, cell cycle analysis, and gene/protein expression of SSC markers. pECM promoted larger, well-defined pSSC colonies and enhanced stemness-related marker expression, including PGP9.5, Thy-1, PLZF, GFRA1, NANOG, and VASA. Additionally, pECM facilitated active pSSC proliferation while suppressing feeder overgrowth, contributing to a stable and functional co-culture environment. Conversely, gelatin supported early feeder proliferation but led to growth saturation, whereas N/C showed delayed attachment and reduced viability. These findings suggest that pECM mimics the native SSC niche and improves pSSC culture. The dual function of pECM in regulating feeder behavior and enhancing pSSC maintenance highlights its potential as a biomaterial for species lacking established feeder-free protocols. Full article

Background/Objectives: Osteoarthritis (OA) is a prevalent age-related degenerative joint disease causing cartilage damage, leading to a debilitating lifestyle. However, there are currently no drugs on the market that promote cartilage repair, and advanced cases often require arthroplasty. Increasing evidence suggests that exosomes, the smallest extracellular vesicles (30–150 nm) secreted by all cell types, are involved in the pathological process of OA and play a crucial and complex role in its progression. This review aims to provide in-depth insights into exosome biology, isolation techniques, their role in OA pathophysiology, and their clinical therapeutic potential. Methods: We systematically reviewed studies published since 2020 on exosomes in OA, focusing on their biological properties, isolation techniques, pathological roles, and therapeutic applications. Results: Exosomes derived from synovial fluid, chondrocytes, synoviocytes, and mesenchymal stem cells regulate key processes in OA progression, including inflammation, apoptosis, extracellular matrix degradation, and regeneration. Various cell-derived exosomes show therapeutic potential for cartilage damage/OA. However, their mechanisms of action have not been fully investigated. Moreover, emerging methodologies, such as utilizing novel materials for exosome delivery, potentially facilitate the development of more effective and personalized therapeutic interventions. Conclusions: Exosomes exert dual roles in OA pathogenesis and therapy. Although challenges remain regarding their sources, dosage, delivery, and standardization, exosome-based strategies represent a promising cell-free therapeutic approach with potential applications in personalized and precision medicine. Full article

Methacrylate photopolymer resin (MPR) is widely used in various fields, including the biomedical field. There are several problems associated with their use: the potential toxicity of monomer residues during incomplete polymerization and the possibility of bacterial expansion. Doping polymers with nanoparticles is one of the ways to increase the degree of polymerization (protection from toxicity), improve the performance characteristics of the polymer, and add antibacterial properties. We used an in situ polymerization method to obtain the composites of MPR with tellurium nanoparticles (TeNPs) with a dopant concentration of 0.001, 0.01, or 0.1% (v/v). The composite of MPR+TeNPs had a higher degree of polymerization compared to MPR without NPs, improved mechanical properties, and pronounced antibacterial activity. The effects depended on the concentration of TeNPs. All of the studied composites had no cytotoxic effect on human cells. MPR+TeNPs 0.1% had the maximum antibacterial effect, which is probably realized through Te-dependent induction of oxidative stress (increase in the generation of 9-oxoguanine and long-lived reactive forms of proteins). The results obtained deepen the knowledge about the influence of NPs of leading metals on photopolymerization and the final properties of the methacrylate matrix, and the synthesized MPR+TeNP composites may find potential biomedical applications in the future. Full article

Phase-change memory (PCM) is a promising candidate for in-memory computation and neuromorphic computing due to its high endurance, low cycle-to-cycle variability, and low read noise. However, among other factors, its performance strongly depends on the post-lithography fabrication steps. This study examines the impact of reactive ion etching (RIE) on PCM device performance by evaluating different etching gas mixtures, CHF₃:O₂, H₂:Ar, and Ar, and determining their impact on key device characteristics, particularly initial resistance and cycling stability. The present study demonstrates that a two-step etching approach in which the capping layer is first removed using H₂:Ar and the underlying GST layer is subsequently etched using physical Ar sputtering ensures stable and reliable PCM operation. In contrast, chemically reactive gases negatively impact the initial resistance, cycling stability, and device lifetime, likely due to alterations in the material composition. For the cycling stability evaluation, an advanced measurement algorithm utilizing the aixMATRIX setup by aixACCT Systems is employed. This algorithm enables automated testing, dynamically adjusting biasing parameters based on cell responses, ensuring a stable ON/OFF ratio and high-throughput characterization. Full article

Decellularized extracellular matrix (dECM) scaffolds preserve native tissue structure and biochemical cues while minimizing immune responses, creating biomimetic templates that promote cell integration and tissue remodeling. This review examines the current state of dECM research, encompassing decellularization methods, scaffold quality evaluation assays, and tissue-specific applications across dermis, nerve, heart, lung, adipose, and placental ECMs. We analyze commercially available dECM products and ongoing clinical trials, while highlighting recent advances including 3D bioprinting and the integration of dECM with stem cells and growth factors. Despite these promising developments, several challenges continue to limit broader clinical translation: protocol standardization, residual immunogenicity, mechanical durability, and regulatory, manufacturing, and cost barriers. To address these limitations, we outline future directions focusing on patient-specific scaffolds, scalable bioprocessing, and integrated biofabrication strategies that will enable the development of safe and effective dECM-based therapies. Full article

Myofibroblasts drive wound healing and fibrotic disease through generation of contractile force to promote wound closure and production of matrix proteins to generate scar tissue. Platelets secrete many pro-wound healing molecules, including cytokines and growth factors. We previously reported that inorganic polyphosphate, secreted by activated platelets, is chemotactic for fibroblasts and induces a myofibroblast phenotype. Using NIH-3T3 cells and primary human fibroblasts, we examined the impact of inhibitors of cell-surface receptors and intracellular signaling molecules on polyphosphate-induced myofibroblast differentiation. We now report that polyphosphate-induced differentiation of fibroblasts to myofibroblasts occurs through a signaling pathway mediated by the receptor for advanced glycation end products (RAGE) and nuclear factor kappa B (NFκB) transcription factor. Inhibition of these signaling components ablated the effects of polyphosphate on fibroblasts. Platelet releasates also induced NFκB signaling and myofibroblast differentiation. Blocking the polyphosphate content of platelet releasates with a biocompatible polyP inhibitor rendered the releasates unable to induce myofibroblast differentiation. These results identify a cell-surface receptor and intracellular transcription factor utilized by platelet polyphosphate to promote wound healing through myofibroblast differentiation and may provide targets for promoting wound healing or altering the disease progression of fibrosis. Full article

Angiotensin II (AngII), the primary effector of the renin-angiotensin system, is essential for maintaining blood pressure and fluid-electrolyte homeostasis. However, elevated AngII levels are a feature of disease conditions such as heart failure and chronic kidney disease, where it is associated with pathological tissue remodeling and fibrosis. AngII-mediated fibrosis has been documented in multiple organs and is characterized by fibroblast expansion, myofibroblast differentiation, and excessive extracellular matrix deposition. Periostin has recently emerged as a marker of fibroblast activation. Notably, periostin expression is highly upregulated during fibrotic remodeling in the kidney and lung, which is strongly linked with impaired organ function. While AngII-induced activation of periostin-lineage (Postn^Lin) cells is well established in the heart, the temporal dynamics of Postn^Lin activation in response to AngII infusion in the lung and kidney remain unexplored. Here, we used a Postn-MerCreMer lineage-tracing approach, combined with continuous AngII infusion over an experimental period of one week and two weeks to assess Postn^Lin responses in lung and kidney. Our findings reveal a progressive activation of Postn^Lin cells in both organs, characterized by myofibroblast phenotype, together with increased collagen deposition and macrophage infiltration. These results highlight the potential of Postn^Lin fibroblasts as a key effector of AngII-mediated tissue remodeling and fibrosis in the lung and kidney. Full article

Asthma is a chronic respiratory disease affecting over 262 million people worldwide, with obesity-associated asthma emerging as a distinct endotype of increasing prevalence characterized by metabolic inflammation and airway remodeling. Unlike allergic asthma, this phenotype is driven by chronic low-grade inflammation, originating from hypertrophic and hypoxic adipose tissue. This dysregulated state leads to the activation of pro-inflammatory pathways and the secretion of cytokines, contributing to airway dysfunction and remodeling. Recent evidence highlights non-coding RNAs (ncRNAs) as key regulators of these processes. MicroRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) influence inflammation and remodeling by modulating immune cell polarization, cytokine secretion, extracellular matrix composition, and airway smooth muscle cell (ASMC) proliferation. Notably, H19, MEG3, GAS5, miR-26a-1-3p, and miR-376a-3p have been implicated in both asthma and obesity, suggesting their role in linking metabolic dysfunction with airway pathology. Moreover, ncRNAs regulate Treg/Th17 balance, fibroblast activation, and autophagy-related pathways, further influencing airway remodeling. Our in silico analysis highlighted the IGF1R signaling pathway as a key enriched mechanism, linking selected ncRNAs with metabolic dysregulation and inflammation in obesity-related asthma. This paper reviews how ncRNAs regulate inflammation and airway remodeling in obesity-associated asthma, emphasizing their potential molecular links between metabolic dysfunction and airway pathology. Full article

The cluster of differentiation 44 (CD44) is a member of the hyaluronic acid (HA) receptor family of cell adhesion molecules. Besides HA, this transmembrane protein also serves as a receptor for other components of the extracellular matrix (ECM), including fibronectin, collagen, and osteopontin (OPN). The CD44-HA axis is involved in a wide range of physiological and cancer-related processes, particularly in cell adhesion and migration, lymphocyte activation, as well as tumour progression and metastasis. The possibility of modulating the CD44-HA interaction with a pharmacological inhibitor has therefore been recognized as an emerging anti-cancer strategy. With its expression in a wide variety, CD44 has also become the most common surface biomarker of cancer stem cells. Due to the rapid progress of research on this crucial receptor, some published and deposited variants were often poorly described or lacked accession numbers in the available protein databases, which created confusion and hindered relevant research. In this work, we attempted to examine the protein sequences of the known CD44 variants and match them between the two UniProt and the National Centre for Biotechnology Information (NCBI) Protein databases. The deposited sequences were aligned to the CD44 canonical sequence and grouped based on the observed differences. Analysis of CD44–ligand experimental structures available in the Protein Data Bank (PDB) was also performed to identify the most promising small-molecule inhibitors of the CD44-HA interaction. Full article