Search Results (2,915)

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

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

Peptides are widely used in cosmetic formulations to stimulate extracellular matrix (ECM) synthesis, while silybin (a flavonolignan from Silybum marianum) offers retinol-like benefits through antioxidant and photoprotective activity. This study evaluated a novel anti-aging cream combining seven bioactive peptides with silybin to assess synergistic effects on ECM regeneration and clinical skin rejuvenation. In vitro assays in human dermal fibroblasts and keratinocytes revealed that the formulation rapidly upregulated gene and protein expression of collagen types I, III, IV, and XVII and lysyl oxidase (LOX) within 4–16 h. Ex-vivo, ultraviolet (UV)-damaged skin explants treated with the peptide–silybin complex showed enhanced recovery of collagen, elastic fibers, and LOX versus untreated controls. A 56-day clinical study (n = 31) demonstrated significant improvements in wrinkle area and volume, elasticity (+12.5%), firmness (+20.7%), and dermal density (+78%, all p < 0.001). No adverse effects were reported, and over 80% of participants noted improved skin texture and firmness. These findings highlight a novel synergy between peptides and silybin, with rapid ECM activation and clinical efficacy. To our knowledge, this is the first evidence of a cosmetic peptide formulation significantly upregulating LOX expression, suggesting a new mechanism for strengthening dermal architecture and improving skin resilience. Future studies should elucidate the mechanisms underlying these effects and assess whether other botanicals confer complementary benefits when combined with peptide blends. Full article

P2Y₂ receptors are a subclass of G protein-coupled receptors activated by the extracellular nucleotides ATP and UTP. These receptors are widely expressed in multiple tissues—including the brain, lungs, heart, and kidneys—and play pivotal roles in inflammation, wound healing, and cell migration. Through coupling with various G proteins, P2Y₂ receptors initiate diverse intracellular signaling pathways that mediate calcium mobilization, cytokine release, and cytoskeletal reorganization. Recent studies highlight their dual roles in health and disease. In physiological contexts, P2Y₂ receptors contribute to immune modulation and tissue repair. In pathological conditions, they are implicated in Alzheimer’s disease by promoting non-amyloidogenic processing of amyloid precursor protein and in dry eye disease by enhancing mucin secretion while modulating ocular inflammation. They also influence chloride secretion and mucosal hydration in cystic fibrosis and contribute to inflammatory regulation and epithelial repair in inflammatory bowel disease. Additionally, P2Y₂ receptors modulate breast cancer progression by regulating cell adhesion, migration, and matrix remodeling. Their involvement in blood pressure regulation via epithelial sodium channel modulation and their facilitative role in HIV-1 entry further underscore their clinical significance. These multifaceted functions position P2Y₂ receptors as promising therapeutic targets for diverse diseases, warranting further investigation for translational applications. Full article

Extracellular vesicles (EVs) from mesenchymal stem cells hold therapeutic promise for inflammatory and degenerative diseases; however, limited delivery and targeting capabilities hinder their clinical use. In this study, we sought to enhance the anti-inflammatory and chondroprotective effects of EVs through CAP-LAMP2b (chondrocyte affinity peptide fused to an EV membrane protein) engineering and ADAMTS4 gene editing hybrid vesicle formation. Human umbilical cord MSCs (hUCMSCs) were characterized via morphology, immunophenotyping, and trilineage differentiation. EVs from control and CAP-LAMP2b-transfected hUCMSCs were fused with liposomes carrying CRISPR-Cas9 ADAMTS4 gRNA. DiI-labeled EV uptake was assessed via fluorescence imaging. CAP-LAMP2b was expressed in hUCMSCs and their EVs. EVs exhibited the expected size (~120 nm), morphology, and exosomal markers (CD9, CD63, CD81, HSP70). CAP-modified hybrid EVs significantly enhanced chondrocyte uptake compared to control EVs and liposomes. IL-1β increased ADAMTS4 expression, whereas CAP-LAMP2b-ADAMTS4 EVs, particularly clone SG3, reversed these effects by reducing ADAMTS4 and restoring aggrecan. Western blotting confirmed suppressed ADAMTS4 and elevated aggrecan protein. CAP-LAMP2b-ADAMTS4 EVs, therefore, showed superior uptake and therapeutic efficacy in inflamed chondrocytes, attenuating inflammatory gene expression and preserving matrix integrity. These results support engineered EVs as a promising cell-free approach for cartilage repair and osteoarthritis treatment. Full article

Collagen VI is an extracellular matrix component encoded by COL6A1, COL6A2 and COL6A3 genes. Causative variants in these genes are associated with the following collagen VI-related myopathies: severe Ullrich congenital muscular dystrophy (UCMD), milder Bethlem myopathy (BM) and intermediate phenotypes (INT). We report the mutation landscape of COL6A genes in 138 Italian patients affected with a collagen VI-related phenotype. The patient cohort included 44 (32%) UCMD, 9 (7%) INT, 61 (44%) BM and 21 (15%) INT/BM patients; 3 patients (2%) with a myosclerosis myopathy (MM) phenotype were also considered. We identified 104 different variants: 26 in COL6A1 (25%), 52 in COL6A2 (50%) and 26 in COL6A3 (25%). The variant spectrum includes missense, splicing, small indel, frameshifting and nonsense variants. Glycine substitutions in the triple helical domain of the collagen VI protein are the commonest variants and occur in all phenotypes. Our genetic profiling disclosed a unique mutation scenario and phenotypic association of the COL6A2 gene with respect to COL6A1 and COL6A3, which may be related to a different evolutive history. Landscape mutation analysis of variants occurring in ultrarare conditions, such as collagen VI-related myopathies, is crucial to better understand the variations’ profile and to gain insight into fundamental knowledge about gene structure and its evolutive origin. Full article

Background: Despite considerable advances to improve colorectal cancer (CRC) survival over the last decade, therapeutic challenges remain due to the rapid metastatic dissemination of primary tumors. This study revealed the apoptotic and anti-growth mechanism of VTD, a previously used anti-hypertensive supplement, can elevate UBXN2A, a known tumor suppressor protein in CRC, and simultaneously enhance intrinsic and extrinsic apoptosis in metastatic cancer cells. Methods and Results: An AOM/DSS mouse model of CRC showed that UBXN2A haplosufficient (UBXN2A +/−) mice treated with VTD had less tumor burden than mice with the full UBXN2A gene treated with vehicle. We have previously shown that casein-coated mesoporous silica nanoparticles (MSNs) offer an effective local delivery of drugs at tumor sites. Our findings demonstrate that the high rate of extracellular release of matrix metalloproteinases (MMPs), particularly MMP-7, by metastatic colon cancer cells, triggers the release of VTD from casein-coated mesoporous MSNs. This shows the “Zip Code” mechanism for the local enrichment of VTD at the tumor sites. After in vitro drug release verification, two independent mouse experiments, a xenograft and a splenolepatic metastatic mouse model of CRC, were used to evaluate the therapeutic efficacy of VTD-loaded and casein-coated carboxylated mesoporous silica nanoparticles, MSN-COOH/VTD/CAS (VTD, 0.2 mg/kg). Animal experiments revealed that MSN-COOH/VTD/CAS (VTD, 0.2 mg/kg) slows down the progress of tumors. Mass spectrometry (MS) revealed improved pharmacokinetics (PK) profile as MSN-COOH/VTD/CAS had less VTD accumulation in non-cancerous organs compared to pure VTD. We further improved nanoparticle targeting and drug release by shifting to calcium-based particles (CBPs). The engineered CBPs demonstrated higher drug-releasing performance. Without the MMPs trigger, MSNs show slow and continuous “drug leak” over longer period of time whereas CCSMPs stops leakage within an hour. Additionally, CBPs showed higher sensitivity to MMP-7 than MMP-9, enhancing the targetability of CBPs for CRC metastatic tumors with excessive extracellular MMP-7. Conclusions: This study introduces a new platform utilizing nanoparticle-based site-specific delivery of a plant-based anti-metastatic molecule, veratridine, with enhanced safety and therapeutic efficacy for the treatment of metastatic CRC. Full article

The puff adder (Bitis arietans) is a clinically relevant viper species found throughout Africa, and it is responsible for a greater incidence of health-related envenomations than all other snake species on the continent combined. Unresolved skeletal muscle damage is a common consequence of B. arietans envenomation that can result in long-term morbidity and even death. Antivenom treatment can mitigate the systemic effects of the venom but offers little protection against local tissue damage. Identifying the mechanisms through which B. arietans venom induces tissue damage and impedes skeletal muscle regeneration could identify possible treatment alternatives that could help alleviate the long-term consequences of envenomation. Skeletal muscle has an innate ability to regenerate, but constituents within the venom can impede multiple stages of this regeneration process. In this study, we employed a combination of biochemical analyses, cell-based assays, and in vivo experiments to assess the toxicological implications of B. arietans envenomation and its impacts on key processes of regeneration. Our findings demonstrate that the pathological characteristics of permanent muscle damage resulting from B. arietans envenomation may be attributed to the venom’s effects on muscle stem cell precursors, the extracellular matrix (ECM), and the influence of blood-borne proteins that promote fibrosis. Full article

(1) Background: The extracellular matrix (ECM) is a natural scaffold for cells, creating a three-dimensional architecture composed of fibrous proteins (mainly collagen) and proteoglycans, which are synthesized by resident cells. In this study, a physiological hypoxic environment was utilized to enhance ECM production by human mesenchymal stem cells (hMSCs), a process relevant to tissue engineering and regenerative medicine. (2) Methods: hMSCs were treated with deferoxamine (DFO), a pharmaceutical hypoxia-mimetic agent that induces cellular responses similar to low-oxygen conditions through stabilization of hypoxia inducible factor-1α (HIF-1α). The time points 0 h 24 h, 3 h 24 h, and 24 h 24 h refer to DFO being added immediately after cell seeding (before cells adhesion), 3 h after cell seeding (during initial cells attachment), and 24 h after cell seeding (after focal adhesions formation and actin organization), respectively, to evaluate the influence of cell adhesion on ECM deposition. hMSCs incubated in culture media were subsequently exposed to DFO for 24 h. Samples were then subjected to cell viability tests, scanning electron microscopy (SEM), atomic force microscopy (AFM) and laser scanning confocal microscopy (CLSM) assessments. (3) Results: Viability tests indicated that DFO concentrations in the range of 0–300 µM were non-toxic over 24 h. The presence of collagen fibers in the DFO-derived ECM was confirmed with anti-collagen antibodies under CLSM. Increased ECM secretion was observed under the following conditions: 3 μM DFO (24 h 24 h), 100 μM DFO (0 h 24 h) and 300 μM DFO (3 h 24 h). SEM and AFM images revealed the morphology of various stages of collagen formation with both collagen fibrils and fibers identified. (4) Conclusions: Our preliminary study demonstrated enhanced ECM secretion by hMSC treated with DFO at concentrations of 3, 100, and 300 µM within a short cultivation period of 24–48 h without significant affecting cell viability. By mimicking physiological processes, it may be possible to stimulate endogenous tissue regeneration, for example, at an injury site. Full article

Corneal regeneration has gained growing interest in recent years, largely due to the limitations of conventional treatments and the persistent shortage of donor tissue. Among the emerging strategies, extracellular vehicles (EVs), especially those derived from mesenchymal stromal cells (MSCs), have shown great promise as a cell-free therapeutic approach. These nanoscale vesicles contribute to corneal healing by modulating inflammation, supporting epithelial and stromal regeneration, and promoting nerve repair. Their therapeutic potential is largely attributed to the diverse and bioactive proteomic cargo they carry, including growth factors, cytokines, and proteins involved in extracellular matrix remodeling. This review presents a comprehensive examination of the proteomic landscape of EVs in the context of corneal regenerative medicine. We explore the biological functions of EVs in corneal epithelial repair, stromal remodeling, and neurodegeneration. In addition, we discuss advanced proteomic profiling techniques such as mass spectrometry (MS) and liquid chromatography–mass spectrometry (LC-MS/MS), which have been used to identify and characterize the protein contents of EVs. This review also compares the proteomic profiles of EVs derived from various MSC sources, including adipose tissue, bone marrow, and umbilical cord, and considers how environmental cues, such as hypoxia and inflammation, influence their protein composition. By consolidating current findings, this article aims to provide valuable insights for advancing the next generation of cell-free therapies for corneal repair and regeneration. Full article

Background: Type 2 diabetes (T2D) is associated with reduced cardiorespiratory fitness (CRF), a critical predictor of cardiovascular disease and all-cause mortality. CRF relies upon the coordinated action of multiple systems including the skeletal muscle where the mitochondria metabolize oxygen and substrates to sustain ATP production. Yet, previous studies have shown that impairments in muscle bioenergetics in T2D are not solely due to mitochondrial deficits. This finding indicates that factors outside the mitochondria, particularly within the local tissue microenvironment, may contribute to reduced CRF. One such factor is the extracellular matrix (ECM), which plays structural and regulatory roles in metabolic processes. Despite its potential regulatory role, the contribution of ECM remodeling to metabolic impairment in T2D remains poorly understood. We hypothesize that pathological remodeling of the skeletal muscle ECM in overweight individuals with and without T2D impairs bioenergetics and insulin sensitivity, and that exercise may help to ameliorate these effects. Methods: Participants with T2D (n = 21) and overweight controls (n = 24) completed a 10-day single-leg exercise training (SLET) intervention. Muscle samples obtained before and after the intervention were analyzed for ECM components, including collagen, elastin, hyaluronic acid, dystrophin, and proteoglycans, using second harmonic generation imaging and immunohistochemistry. Results: Positive correlations were observed with elastin content and both glucose infusion rate (p = 0.0010) and CRF (0.0363). The collagen area was elevated in participants with T2D at baseline (p = 0.0443) and showed a trend toward reduction following a 10-day SLET (p = 0.0867). Collagen mass remained unchanged, suggesting differences in density. Dystrophin levels were increased with SLET (p = 0.0256). Conclusions: These findings identify that structural proteins contribute to aerobic capacity and identify elastin as an ECM component linked to insulin sensitivity and CRF. 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

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

Periodontitis has been associated with adverse pregnancy outcomes, but the effect of oral pathogens on placental tissue and local immunity remains unclear. In this study, we investigated the response of human placental explants (HPEs) to lysates of Porphyromonas (P.) gingivalis, a keystone periodontal pathogen. Exposure to P. gingivalis induced significant histological damage and extracellular matrix degradation in placental tissue. The lysate activated the canonical NF-κB pathway, as demonstrated by increased phosphorylation of IκBα, particularly in the trophoblast. This activation was predominantly mediated by Toll-like receptor 2 (TLR-2), with partial contribution from TLR-4. Notably, TLR-2 protein levels decreased upon stimulation, while soluble (s) TLR-2 was markedly elevated in culture supernatants, suggesting receptor cleavage as a regulatory mechanism. P. gingivalis also triggered a robust proinflammatory cytokine secretion, including IL-1β, IL-6, IL-8, and TNF-α, with variable dependence on TLR-2 and TLR-4 signaling. These findings reveal that P. gingivalis components elicit a complex innate immune response in the placenta, driven by TLR-mediated NF-κB activation and modulated by sTLR-2. This study provides mechanistic insight into how periodontitis may contribute to placental inflammation and highlights potential pathways linking maternal oral health to pregnancy complications. 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