Search Results (3,387)

Background: Intervertebral disc degeneration (IVDD) is closely linked to low back pain (LBP), a leading cause of disability worldwide. IVDD is characterized by the loss of proteoglycans (PGs), extracellular matrix (ECM) degradation, and reduced hydration of the nucleus pulposus (NP). Extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (hUC-MSCs) exhibit tissue repair and immunomodulatory effects and are emerging as promising cell-free therapeutics. Methods: We established a rat IVDD model via fluoroscopy-guided needle puncture of three consecutive coccygeal discs and confirmed degeneration through Alcian Blue and hematoxylin & eosin (H&E) staining. The gene expression of inflammatory and pain markers (ADRβ2, COMP, CXCL1, COX2, PPTA, MMP13, YKL40) was measured by qPCR. Subsequently, we implanted hUC-MSCs or EVs to evaluate their reparative potential. Results: Upregulation of inflammatory and pain genes in IVDD was associated with an immunomodulatory response. Tracking DiI-labelled hUC-MSCs and EVs revealed enhanced survival of hUC-MSCs, retention of EVs, and dispersion within rat tail discs; EVs showed greater retention than hUC-MSCs. Implanted EVs were internalized by NP cells and remained within degenerative IVDs. EVs passively diffused, accumulated at the injury site, interacted with host cells, and enhanced function, as shown by increased expression of human chondrocyte-related markers (SOX9, TGFβ1, TGFβ2, COL2) compared to hUC-MSC treatment. Histological analysis of two weeks post-transplantation showed NP cellular patterns resembling chondromas in treated discs. EVs integrated into and distributed within degenerated NP regions, with greater glycosaminoglycan (GAG) content. Conclusions: Overall, hUC-MSC EVs demonstrated superior regenerative capacity, supporting a safe, cell-free strategy for disc repair. Full article

Dynamic compression (DC) bioreactors are widely used to mimic joint loading and study how human mesenchymal stem cells (hMSCs) respond to mechanical cues. However, it remains unclear whether DC alone is sufficient to induce chondrogenesis or how such cues interact during construct maturation. In this study, hMSCs were encapsulated in fibrin hydrogels at different cell densities and subjected to DC without, during, or after TGF-β3-mediated chondrogenic induction. DC alone modestly increased SOX9 expression but failed to upregulate key cartilage matrix genes such as ACAN and COL2A1, indicating that mechanical stimulation alone is insufficient to initiate chondrogenesis. When mechanical stimulation was coupled with TGF-β3, a more mature chondrogenic phenotype was observed for high cell seeding densities (HD). To simulate a post-implantation scenario, we applied DC following growth factor withdrawal and observed marked downregulation of SOX9, ACAN, and COL2A1 in low-density (LD) constructs. This reduction was not observed in HD constructs, which maintained a more stable chondrogenic phenotype under loading. These findings show that construct maturation critically influences mechanoresponsiveness and suggest that immature grafts may not tolerate mechanical stimulation. DC bioreactors may therefore serve not only to support cartilage engineering but also to predict in vivo graft performance. Full article

Pulmonary fibrosis (PF) is a progressive and fatal lung disease characterized by irreversible alveolar destruction and pathological extracellular matrix (ECM) deposition. Currently approved agents (pirfenidone and nintedanib) slow functional decline but do not reverse established fibrosis or restore functional alveoli. Multifunctional bioscaffolds present a promising therapeutic strategy through targeted modulation of critical cellular processes, including proliferation, migration, and differentiation. This review synthesizes recent advances in scaffold-based interventions for PF, with a focus on their dual mechano-epigenetic regulatory functions. We delineate how scaffold properties (elastic modulus, stiffness gradients, dynamic mechanical cues) direct cell fate decisions via mechanotransduction pathways, exemplified by focal adhesion–cytoskeleton coupling. Critically, we highlight how pathological mechanical inputs establish and perpetuate self-reinforcing epigenetic barriers to regeneration through aberrant chromatin states. Furthermore, we examine scaffolds as platforms for precision epigenetic drug delivery, particularly controlled release of inhibitors targeting DNA methyltransferases (DNMTi) and histone deacetylases (HDACi) to disrupt this mechano-reinforced barrier. Evidence from PF murine models and ex vivo lung slice cultures demonstrate scaffold-mediated remodeling of the fibrotic niche, with key studies reporting substantial reductions in collagen deposition and significant increases in alveolar epithelial cell markers following intervention. These quantitative outcomes highlight enhanced alveolar epithelial plasticity and upregulating antifibrotic gene networks. Emerging integration of stimuli-responsive biomaterials, CRISPR/dCas9-based epigenetic editors, and AI-driven design to enhance scaffold functionality is discussed. Collectively, multifunctional bioscaffolds hold significant potential for clinical translation by uniquely co-targeting mechanotransduction and epigenetic reprogramming. Future work will need to resolve persistent challenges, including the erasure of pathological mechanical memory and precise spatiotemporal control of epigenetic modifiers in vivo, to unlock their full therapeutic potential. Full article

Osteoarthritis (OA) is a degenerative joint disease characterized by progressive cartilage breakdown, synovial inflammation, and subchondral bone remodeling. Previous studies have shown that cellular communication network factor 3 (CCN3) expression increases with age in cartilage, and its overexpression promotes OA-like changes by inducing senescence-associated secretory phenotypes. This study aimed to investigate the effect of Ccn3 knockout (KO) on OA development using a murine OA model. Destabilization of the medial meniscus (DMM) surgery was performed in wild-type (WT) and Ccn3-KO mice. Histological scoring and staining were used to assess cartilage degeneration and proteoglycan loss. Gene and protein expressions of catabolic enzyme (Mmp9), hypertrophic chondrocyte marker (Col10a1), senescence marker, and cyclin-dependent kinase inhibitor 1A (Cdkn1a) were evaluated. Single-cell RNA sequencing (scRNA-seq) data from WT and Sox9-deficient cartilage were reanalyzed to identify Ccn3⁺ progenitor populations. Immunofluorescence staining assessed CD44 and Ki67 expression in articular cartilage. The effects of Ccn3 knockdown on IL-1β-induced Mmp13 and Adamts5 expression in chondrocytes were examined in vitro. Ccn3 KO mice exhibited reduced cartilage degradation and catabolic gene expression compared with WT mice post-DMM. scRNA-seq revealed enriched Ccn3-Cd44 double-positive cells in osteoblast progenitor, synovial mesenchymal stem cell, and mesenchymal stem cell clusters. Immunofluorescence showed increased CCN3⁺/CD44⁺ cells in femoral and tibial cartilage and meniscus. Ki67⁺ cells were significantly increased in DMM-treated Ccn3 KO cartilage, mostly CD44⁺. In vitro Ccn3 knockdown attenuated IL-1β-induced Mmp13 and Adamts5 expressions in chondrocytes. Ccn3 contributes to OA pathogenesis by promoting matrix degradation, inducing hypertrophic changes, and restricting progenitor cell proliferation, highlighting Ccn3 as a potential therapeutic target for OA. Full article

Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) are E. coli pathovars of particular relevance to infant health. While the intestinal tract of humans and animals constitutes their primary habitat, these bacteria can also persist in natural environments such as sand. The aim of this study was to evaluate the persistence of STEC and EPEC strains in sand microcosms under controlled conditions of heat and desiccation in order to estimate their viability in this matrix and provide evidence regarding the potential risks associated with the use of sandboxes in public spaces. The study included STEC strains belonging to clinically important serotypes (O26:H11, O103:H2, O111:H8, O121:H19, O145:NM, O157:H7 and O174:H28), animal-derived EPEC strains, and a non-pathogenic E. coli strain (NCTC 12900). The strains were inoculated into sterile sand microcosms and maintained at 37 °C. Death curves, persistence in the matrix, presence of virulence genes, and ability to produce biofilm were evaluated. The death and persistence curves varied by serotype; some strains remained viable in the viable but non-culturable state for extended periods. All strains retained their virulence-associated genetic markers throughout the assays. None of the STEC strains was classified as a biofilm producer under the experimental conditions, whereas the two EPEC strains were identified as weak and moderate biofilm producers. However, no association was found between biofilm formation and persistence in the matrix. The findings provide an initial approach and provide relevant evidence of the capacity of STEC and EPEC strains to survive in sand, which could represent a potential risk in recreational environments. Full article

Radiation resistance presents a significant challenge in the treatment of triple-negative breast cancer (TNBC). To investigate the molecular adaptations associated with radiation therapy resistance, MDA-MB-231 cells were subjected to a repeated radiation (RR) regimen totaling 57 Gy over 11 weeks, followed by clonal selection. The resulting radiation-adapted cells (MDA-MB-231^RR) were analyzed using whole-transcriptome RNA sequencing, revealing substantial dysregulation of pathways related to cell adhesion, mitochondrial function, and epithelial–mesenchymal transition (EMT). These transcriptional changes were corroborated by functional assays. MDA-MB-231^RR cells exhibited reduced expression of adhesion receptors (ITGB1, ITGA2, ITGA6) and extracellular matrix proteins (fibronectin, collagen, laminins), accompanied by significantly impaired cell adhesion to fibronectin, collagen, and laminin substrates. Mitochondrial dysfunction was supported by downregulation of oxidative phosphorylation genes (MTCO1, MTND1) and confirmed by JC-1 dye assays demonstrating a marked reduction in mitochondrial membrane potential. EMT-associated changes included increased mesenchymal markers and loss of epithelial markers (CTNNB1, SNAI2, CK19), consistent with enhanced migratory potential. Taken together, this study delineates key molecular features of radiation adaptation in TNBC, providing a foundation for the development of targeted therapies to overcome treatment resistance. Full article

Antlers are unique mammalian organs that grow rapidly through extensive cartilage proliferation. Vitamin A (VA), via retinoic acid, is known to influence skeletal development, yet its contribution to antler growth remains unclear. We investigated whether rumen-protected VA supplementation modulates antler biology in sika deer by integrating gut microbiota profiling, fecal and serum metabolomics, antler cartilage transcriptomics, and in vitro chondrocyte assays. VA was associated with compositional shifts in the gut microbiota and altered metabolic profiles in feces and serum. Notably, the melatonin-derived metabolite AMFK increased in both matrices and showed strong associations with antler weight and cartilage-related gene expression. VA-supplemented deer exhibited higher antler weight, and antler transcriptomes indicated changes in pathways consistent with cartilage extracellular matrix and growth signaling. In chondrocytes, AMFK promoted proliferation and upregulated chondrogenic markers. Together, these findings suggest that VA may promote antler growth through a microbiota–metabolite–gene axis rather than by altering systemic retinol alone. Full article

The global transition to a circular bioeconomy is accelerating the demand for sustainable, high-performance materials. Filamentous fungi represent a promising solution, as they function as living foundries that transform low-value biomass into advanced, self-assembling materials. While mycelium-based composites have proven potential, progress has been predominantly driven by empirical screening of fungal species and substrates. To unlock their full potential, a paradigm shift from empirical screening to rational design is required. This review introduces a conceptual framework centered on the biochemical programming of the fungal cell wall. Viewed through a materials science lens, the cell wall is a dynamic, hierarchical nanocomposite whose properties can be deliberately tuned. We analyze the contributions of its principal components—the chitin–glucan structural scaffold, the glycoprotein functional matrix, and surface-active hydrophobins—to the bulk characteristics of mycelium-derived materials. We then identify biochemical levers for controlling these properties. External factors such as substrate composition and environmental cues (e.g., pH) modulate cell wall architecture through conserved signaling pathways. Complementing these, an internal synthetic biology toolkit enables direct genetic and chemical intervention. Strategies include targeted engineering of biosynthetic and regulatory genes (e.g., CHS, AGS, GCN5), chemical genetics to dynamically adjust synthesis during growth, and modification of surface chemistry for specialized applications like tissue engineering. By integrating fungal cell wall biochemistry, materials science, and synthetic biology, this framework moves the field from incidental discovery toward the intentional creation of smart, functional, and sustainable mycelium-based materials—aligning material innovation with the imperatives of the circular bioeconomy. Full article

Eucommia ulmoides Oliver (E. ulmoides), a traditional medicinal plant, has been widely used for its antioxidant and anti-inflammatory properties. However, its effects on dental tissue regeneration remain largely unexplored. In this study, we investigated the odontogenic potential of E. ulmoides extract in human dental pulp stem cells (hDPSCs). Cell viability was assessed using the cell counting kit-8 (CCK-8) assay, and antioxidant activity was evaluated via the DPPH radical scavenging method. Odontoblast differentiation was examined using Alizarin Red S (ARS) staining, real-time PCR, and Western blot analysis of key differentiation markers, including dentin matrix protein 1 (DMP-1) and dentin sialophosphoprotein (DSPP). Our results demonstrated that E. ulmoides extract enhanced mineralization and upregulated both gene and protein expression of odontoblast differentiation markers in a dose-dependent manner. Furthermore, signaling pathway analysis revealed that E. ulmoides extract activated the SMAD pathway while downregulating ERK and p38 MAPK phosphorylation during odontogenic differentiation. These findings suggest that E. ulmoides extract promotes odontoblast differentiation in hDPSCs and may serve as a promising natural agent for dental tissue regeneration. These findings further underscore its potential clinical relevance as a therapeutic candidate to enhance dental tissue repair and regeneration. Full article

This study investigated the mechanism of hydroxysafflor yellow A (HSYA) on senescent human umbilical cord mesenchymal stem cells (hUC-MSCs) through transcriptome sequencing. HSYA treatment identified 2377 differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that these DEGs were primarily enriched in cell adhesion regulation and the extracellular matrix (ECM)–receptor interaction pathway. Gene Set Enrichment Analysis (GSEA) and protein–protein interaction (PPI) network analysis corroborated the central role of ECM–receptor interaction signaling, and Key Driver Analysis (KDA) revealed 10 core regulatory genes (e.g., ID1, SMAD3, TGFB3). SA-β-gal staining showed that HSYA significantly reduced senescence-associated β-galactosidase activity. Flow cytometry showed no significant changes in cell cycle distribution. Western blot analysis indicated that HSYA treatment reduced the protein expression level of p16 without significantly altering p53 levels. Furthermore, HSYA significantly attenuated intracellular reactive oxygen species (ROS) accumulation. qPCR validation demonstrated that HSYA significantly upregulated ID1, GDF5, SMAD3, and TGFB3 while downregulating BMP4, TGFB2, and CCN2. These findings indicate that HSYA modulates genes associated with the ECM–receptor interaction pathway, potentially contributing to improved ECM homeostasis in senescent hUC-MSCs. Full article

Major depressive disorder (MDD) is one of the most common diseases, affecting millions of people worldwide. Existing antidepressants do not allow sustainable remission to be achieved in many cases, probably due to insufficient understanding of the etiopathogenesis of MDD. The aim of this study was to identify the key genes, pathways, and master regulators associated with MDD based on a combination of genomic and transcriptomic data analyses. We performed a transcriptome-wide association study (TWAS) to identify the increase and decrease in transcription of particular genes that can be associated with MDD risk, the results of which were used to perform a pathway enrichment analysis that elucidated the pathways and processes associated with MDD. Besides changes in the metabolism of neurotransmitters, the association of some other processes with MDD was revealed, including changes in phospholipid and glycan metabolism, chromatin remodeling, RNA processing and splicing, and cell–extracellular matrix interaction. The transcriptomic analysis performed for brain regions mostly confirmed genome-level findings. The gene expression changes in the brain related to MDD were mostly sex-specific, and the transcription of many genes was changed in the opposite direction in males and females. Finally, master regulators were found, which are the proteins responsible for the transcriptional regulation of the revealed genes and represent the most important proteins contributing to MDD development. Full article

Background/Objectives: The design of scaffolds that mimic the extracellular matrix has gained increasing attention in regenerative medicine. This study aims to develop and characterize electrospun nanofibrous scaffolds based on pullulan blended with either gelatin or gliadin and doped with selenium nanoparticles (Se NPs), to assess the influence of protein type and Se NP doping on scaffold performance and regenerative potential. Methods: Se NPs were synthesized via redox reaction and stabilized using pullulan. Electrospun scaffolds were then prepared by blending pullulan-stabilized Se NPs with either gelatin or gliadin. The resulting fibers were characterized using a multidisciplinary approach, including physicochemical (morphology, fiber dimension, swelling capacity, surface zeta potential, mechanical properties) and preclinical properties (antioxidant properties, fibroblast adhesion and proliferation, collagen expression). Results: Protein type influenced fiber morphology and dimensions, as well as mechanical behavior, with gelatin-based scaffolds demonstrating smaller fiber diameters and higher mechanical properties. The doping with Se NPs enhanced scaffold antioxidant properties without affecting fiber formation. Moreover, all scaffolds supported fibroblast proliferation, but those containing Se NPs showed enhanced modulation of ECM gene expression. Conclusions: The results show that scaffolds doped with Se NPs exhibited superior performance compared to the undoped counterparts, offering promising platforms for chronic wound reparation. Full article

Background/Objectives: Enhancement of cellular NAD⁺ mediated by NMN has emerged as a pivotal strategy in modulating the aging process. This study aimed to systematically investigate the anti-aging effects of NMN on human skin fibroblasts, focusing on how the former contributes to the improvement of cellular health and function. This study elucidated the molecular and functional mechanisms by which NMN contributes to the attenuation of skin aging. Methods: We performed extensive in vitro and transcriptomic analyses. Human skin fibroblasts were treated with NMN, and the induced biological responses were observed under oxidative stress/photo-aging models. Results: Transcriptome analysis revealed distinct gene expression patterns for NAD⁺ and its precursors (NMN, NR, and NAM), showing significant differences between NMN and other precursors (NR and NMN). NMN seemed to be significantly involved in cytokine and chemokine activity. It significantly elevated cellular NAD⁺ levels, activated sirtuin and autophagy pathways, and enhanced mitochondrial function, collectively maintaining cellular homeostasis under stress. Furthermore, it suppressed cellular senescence, promoted cell proliferation, supported extracellular matrix integrity, and accelerated wound healing. Conclusions: The study provided essential mechanistic evidence supporting the anti-aging effects of NMN in skin cells and addressed the current lack of scientific validation of NMN-based topical applications. The findings established a solid academic background for future translational research and the development of NMN-based therapeutics and cosmeceuticals. Full article

The role of mesenchymal-to-endothelial transition in the angiogenic response remains controversial. In this study, we investigated whether human fetal lung fibroblasts (MRC-5 cells) exhibit morphological plasticity in a biomimetic extracellular matrix environment. To this end, MRC-5 cells were first cultured on and within Matrigel hydrogel and then studied with tube formation assays, confocal/fluorescence microscopy, invasion assays, and transcriptomic profiling. In addition, quantitative assessment for cord formation and gene expression was conducted via qPCR and RNA sequencing. In this study, MRC-5 cells quickly self-organized into cord-like networks, resembling early stages of vascular patterning, and at higher densities, invaded the hydrogel and formed spheroid-like aggregates. Transcriptomic analysis revealed upregulation of genes related to nervous system development and synaptic signaling in Matrigel-grown MRC-5 cultures. Collectively, these findings suggest that MRC-5 fibroblasts display structural and transcriptional plasticity in 3D Matrigel cultures, forming vascular-like cords that are more likely to resemble early developmental morphologies or neuroectodermal-like transcriptional signatures than definitive endothelial structures. This work underscores the potential of fibroblasts as an alternative cell source for vascular tissue engineering and highlights a strategy to overcome current limitations in autologous endothelial cell availability for regenerative applications. Full article

Scleral tissue is a connective tissue made up of dense, intertwined collagen fibers that plays a vital part in preserving both the integrity of vision and the shape of the eyeball. Numerous studies have been conducted on the impact of terahertz radiation on biological systems. Terahertz radiation can affect cell morphology and function by mediating modifications in protein conformation and gene expression, according to recent research. Though terahertz waves found in the environment directly expose scleral tissue, little is known about how terahertz radiation affects scleral fibroblasts biologically. In this work, we investigated how 0.1 THz radiation affected the global expression levels of proteins and the viability of human fetal scleral fibroblasts (HFSFs). A total of 79.44% of the differentially expressed proteins (DEPs) showed significant downregulation in expression levels after 60 min of exposure to terahertz radiation. Enrichment analysis of DEPs revealed that terahertz radiation enhanced the expression of cytoskeletal keratins, disrupted supercoplexes’ assembly, and impaired mitochondrial respiration. Moreover, terahertz radiation influences the remodeling process of the scleral extracellular matrix by triggering the TGF-β/Smad signaling pathway. Changes in transcriptional activity of several extracellular matrix (ECM)-related genes persisted for 12 h in the absence of terahertz radiation. Research findings indicate that 0.1 THz radiation is capable of disrupting the dynamic balance between collagen synthesis and degradation in scleral fibroblasts. Such an imbalance may induce alterations in the structural integrity and biomechanical properties of the sclera, thereby elevating the potential risk of myopia onset or progression. Full article