Search Results (196)

Type 1 diabetes (T1D) is caused by autoimmune-mediated destruction of pancreatic β-cells, resulting in insulin deficiency. While islet transplantation presents a potential therapeutic approach, its clinical application is impeded by limited donor availability and the risk of immune rejection. This study proposes an innovative islet encapsulation strategy that utilizes decellularized porcine pancreatic extracellular matrix (pECM) as the sole biomaterial to engineer bioactive, immunoprotective microcapsules. Rat islets were encapsulated within pECM-based microcapsules using the electrospray technology and were compared to conventional alginate-based microcapsules in terms of viability, function, and response to hypoxic stress. The pECM microcapsules maintained a spherical morphology, demonstrating mechanical robustness, and preserving essential ECM components (collagen I/IV, laminin, fibronectin). Encapsulated islets exhibited sustained viability and superior insulin secretion over a two-week period compared to alginate controls. The expression of key β-cell transcription factors (PDX1, MAFA) and structural integrity were preserved. Under hypoxic conditions, pECM microcapsules significantly reduced islet apoptosis, improved structural retention, and promoted functional recovery, likely due to antioxidant and ECM-derived cues inherent to the pECM. In vivo transplantation in immunocompetent mice confirmed the biocompatibility of pECM microcapsules, with minimal immune responses, stable insulin/glucagon expression, and no adverse systemic effects. These findings position pECM-based microencapsulation as a promising strategy for creating immunoprotective, bioactive niches for xenogeneic islet transplantation, with the potential to overcome current limitations in cell-based diabetes therapy. Full article

Bovine endometritis is a common endocrine and reproductive disorder in postpartum dairy cows, closely associated with elevated systemic oxidative stress. This disease can lead to delayed uterine involution, repeated breeding failure, and significant economic losses in the dairy industry. Studies suggest that oxidative stress may contribute to the pathological progression of endometritis by regulating ECM remodeling, but the specific molecular mechanisms remain unclear. ECM homeostasis relies on the coordinated action of matrix metalloproteinases (e.g., MMP2, MMP9) and collagen (e.g., type IV collagen, COL-IV), while the TGFβ1/Smad3 signaling pathway is implicated in ECM metabolic regulation. Therefore, elucidating the regulatory mechanisms of oxidative-stress-mediated TGFβ1/Smad3 signaling on ECM remodeling is crucial for understanding the pathogenesis of endometritis. This study investigates postpartum bovine uterine tissues, comparing inflammatory cytokines (IL-1β, IL-6, TNF-α) and oxidative-stress-related factors (GPx, SOD, CAT) between healthy and endometritis groups. Additionally, the differences in ECM-remodeling-associated proteins (MMP2, MMP9, COL-IV) and TGFβ1/Smad3 pathway activity are analyzed. To further validate the mechanisms, an oxidative stress model is established in vitro by treating bovine endometrial epithelial cells (bEECs) with 200 μM H₂O₂ for 4 h, followed by the valuation of the same indicators. Furthermore, gene silencing to downregulate Smad3 expression or inhibitor-mediated suppression of TGFβ1/Smad3 pathway activity is performed to observe their regulatory effects on MMP2, MMP9, and COL-IV. The results demonstrate that oxidative-stress-mediated endometritis significantly upregulates MMP2, MMP9, and the TGFβ1/Smad3 pathway activity, while suppressing COL-IV expression. Functional genetic experiments further reveal the dual regulatory role of the TGFβ1/Smad3 pathway in ECM remodeling: (1) pathway activation promotes MMP2/MMP9 expression, accelerating COL-IV degradation; (2) Smad3 positively regulates COL-IV synthesis. These findings provide a theoretical basis for targeting the TGFβ1/Smad3 pathway to mitigate the pathological progression of endometritis. Full article

Pathogenic variants in type IV collagen genes (COL4A3, COL4A4, COL4A5) are classically associated with Alport syndrome (AS), a hereditary nephropathy primarily affecting the glomerular basement membrane (GBM). Recent findings, however, suggest a broader phenotypic spectrum that includes renal cyst formation, raising questions about overlapping mechanisms with other cystic kidney diseases. Clinically, renal cysts have been increasingly reported in patients with autosomal dominant and X-linked forms of Alport syndrome, particularly in association with glycine missense variants. The most recent studies focusing on the cystic phenotype in Alport syndrome provide growing support for the idea that variants in type IV collagen genes are associated with an increased likelihood of developing renal cysts, likely through mechanisms involving the structural integrity of renal basement membranes. In this review, we explore evidence from murine models and human studies indicating defects in collagen IV and discuss their contribution to cystogenesis. These observations underscore the need for broader genetic screening strategies and further investigation into the molecular mechanisms underlying this emerging phenotype. Full article

Background/Objectives: Immune cells are integral to bone homeostasis, including the repair and remodeling of bone tissue. Chronic dysregulation within this osteoimmune network can lead to bone marrow defects of the jaw (BMDJ), particularly fatty degenerative osteonecrosis of the jaw (FDOJ). These localized pathologies are implicated in systemic immune dysfunctions. Methods: This study is designed to determine whether BMDJ/FDOJ samples are indicative of medullary bone pathology by evaluating FDOJ gene expression patterns using quantitative real-time PCR. Results: Comparative analyses between pathological and healthy samples evaluated the dysregulation of key molecular pathways. BMDJ/FDOJ samples showed significant upregulation of inflammatory mediators, including CCL5/RANTES, VEGF, IGF and KOR, and downregulation of structural proteins, such as collagen types I, II and IV, and osteogenesis-associated factors, such as SP7. Conclusions: The study provides new insights into the molecular mechanisms of BMDJ/FDOJ by identifying potential molecular changes suggesting a pro-inflammatory state in the affected jawbone which may contribute to systemic immune dysregulation. The findings are consistent with morphologic observations of BMDJ/FDOJ in degenerated jawbone and underscore the need for integrative approaches in dentistry and medicine while highlighting BMDJ/FDOJ as a potential target for therapeutic and preventive strategies against systemic diseases and emphasizing its clinical significance. Full article

Vascular basement membranes (BMs), composed of laminins, collagen IV, fibronectin, and perlecan, are secreted by endothelial cells, pericytes, smooth muscle cells (SMCs), and astrocytes. In the brain, amyloid beta (Aβ) is eliminated along cerebrovascular BMs of capillaries and arteries as intramural periarterial drainage (IPAD). Ageing modifies vascular BMs, impairing IPAD and leading to Aβ deposition as cerebral amyloid angiopathy. To better understand the molecular determinants of IPAD in ageing, we quantified the relative abundance of BMs secreted by human-derived cerebral endothelial cells, pericytes, brain vascular SMCs, and astrocytes in vitro. We then assessed BM protein levels in SMCs under hypercapnia (8% CO₂) as a model of vascular ageing, with and without Aβ exposure. Of the four cell types, we found SMCs secreted the highest levels of fibronectin, laminin, and perlecan, whilst pericytes secreted the highest levels of collagen IV. Hypercapnia increased the expression of collagen IV and fibronectin in SMCs but decreased the expression of laminin. The expression of perlecan increased under hypercapnia, but only in the presence of Aβ. This work highlights the varying compositions of vascular BMs and the dynamic differential responses of SMCs to Aβ and hypercapnia, helping to elucidate the age-related changes that impair IPAD in cerebral vessels. Full article

Studies have consistently shown that long-wave ultraviolet A (UVA) radiation triggers skin photoaging, which is evident as reduced elasticity, a loss of firmness, and signs of aging. There is an urgent need to investigate photoaging mechanisms to devise protective strategies against UVA. The present study aimed to explore the effects of recombinant type XVII collagen on UVA-induced skin aging and uncover its molecular mechanisms, thereby laying a solid theoretical foundation for precise treatments and prevention. We therefore modeled photoaging damage in HaCaT cells and evaluated collagen-related protein and gene expression levels via western blot analysis and real-time quantitative polymerase chain reaction analysis. Immunofluorescent staining was also used to assess collagen secretion and basement membrane protein expression. Recombinant type XVII collagen significantly boosted type IV and type XVII collagen, laminin alpha 5, and integrin β1 production, thus counteracting UVA-induced collagen decline. The polymerase chain reaction analysis revealed matrix metalloproteinase (MMP) downregulation and tissue inhibitor of metalloproteinase (TIMP) upregulation. Modulating the transforming growth factor (TGF)-β/Smad and epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) pathways suppressed photoaging. Together, our findings suggest that recombinant type XVII collagen ameliorates UVA-induced damage by reversing MMP and TIMP gene expression, thereby preventing collagen degradation and enhancing basement membrane secretion. These results offer a theoretical basis for potent anti-photoaging products, thus paving the way for innovative solutions against UVA-induced skin aging. Full article

Collagen is the main protein found in skin, bone, cartilage, ligaments, tendons and connective tissue, and it can exhibit properties ranging from compliant to rigid or form gradients between these states. The collagen family comprises 28 members, each containing at least one triple-helical domain. These proteins play critical roles in maintaining mechanical characteristics, tissue organization, and structural integrity. Collagens regulate cellular processes such as proliferation, migration, and differentiation through interactions with cell surface receptors. Fibrillar collagens, the most abundant extracellular matrix (ECM) proteins, provide organs and tissues with structural stability and connectivity. In the mammalian myocardial interstitium, types I and III collagens are predominant: collagen I is found in organs, tendons, and bones; collagen II is found in cartilage; collagen III is found in reticular fibers; collagen IV is found in basement membranes; and collagen V is found in nails and hair. Recombinant human collagens, particularly in sponge-like porous formats combined with bone morphogenetic proteins, serve as effective scaffolds for bone repair. Due to their biocompatibility and low immunogenicity, collagens are pivotal in tissue engineering applications for skin, bone, and wound regeneration. Recombinant technology enables the production of triple-helical collagens with amino acid sequences identical to human tissue-derived collagens. This review summarizes recent advances in the molecular functions and recombinant expression of human collagens, with a focus on their biomedical applications. Full article

Background: Alport syndrome (AS) is one of the most common monogenic kidney disorders. Recent studies have highlighted the modifier effect of variants involving podocyte and non-collagenous extracellular matrix (ECM) proteins in AS. Methods: We report a case series of eight patients with genetically proven AS and simultaneous variants involving podocyte and non-collagenous ECM proteins. Our aim is to describe the influence of such variants on the phenotype of patients with AS. Results: We identified 10 different type IV collagen variants. Patients were diagnosed with autosomal dominant (3/8), autosomal recessive (2/8), digenic (2/8) and X-linked AS (1/8). There were eight different variants involving podocyte and non-collagenous ECM proteins. The genes involved were CRB2, LAMA5, LAMB2, NUP107, MYO1E and PLCE1. Four patients (LAMB2, LAMA5 and PLCE1 variants) presented with nephrotic syndrome or nephrotic range proteinuria. Two patients had hearing loss. Most patients (7/8) had a family history of kidney disease. Two patients (LAMB2 and LAMA5 variants) were diagnosed with focal segmental glomerulosclerosis. Two patients developed end-stage kidney disease (LAMA5, MYO1E and NUP107 variants). Conclusions: Although mutations of podocyte and ECM proteins do not have phenotypic expression in monoallelic form, the presence of such variants could explain the phenotypic variability of AS. Full article

Collagen and its peptides exhibit remarkable antioxidant activity, superior biocompatibility, and water solubility, making them a significant research focus in skin care. Hence, the recombinant humanized collagen types I, III, and XVII complexed with niacinamide were developed to address damage in human foreskin fibroblasts (HFF-1) caused by ultraviolet radiation and to evaluate basement membrane proteins in a rat skin model. The Cell Counting Kit-8 (CCK-8) assay showed that higher concentrations of the complex increased the survival of damaged cells by approximately 10% and 22%, respectively, compared to the normal group after 16 and 48 h of treatment. Further biochemical analyses using ELISA and immunofluorescence (IF) confirmed that the complex enhanced the expression of collagen type IV, laminin, P63, and transforming growth factor-β (TGF-β) in the damaged cells. Additionally, the complex boosted the activity of the basement membrane in rat skin and stimulated the secretion of integrin, laminin, and perlecan. Overall, the recombinant humanized collagen complex effectively reinforced the skin’s basement membrane. Full article

Matrix metalloproteinase-2 (MMP-2), a zinc-dependent enzyme, plays a critical role in the degradation and remodeling of the extracellular matrix (ECM). As a member of the gelatinase subgroup of matrix metalloproteinases, MMP-2 is involved in a variety of physiological processes, including tissue repair, wound healing, angiogenesis, and embryogenesis. It is primarily responsible for the degradation of type IV and V collagen, fibronectin, laminin, and elastin, which are essential components of the ECM. MMP-2 is secreted as an inactive pro-enzyme (proMMP-2) and activated through proteolytic cleavage, with its activity being precisely regulated by tissue inhibitors of metalloproteinases (TIMPs). Dysregulation of MMP-2 has been linked to a variety of pathological conditions, including cardiovascular diseases, diabetic complications, kidney diseases, and cancer. In cardiovascular diseases, it contributes to vascular remodeling, atherosclerosis, and aneurysms, while in fibrotic diseases, it mediates excessive ECM degradation leading to tissue scarring. In diabetes, elevated MMP-2 activity exacerbates complications such as nephropathy, retinopathy, and cardiovascular disease. In cancer, MMP-2 facilitates tumor invasion and metastasis by degrading ECM components and promoting angiogenesis. Despite its essential roles in both physiological and pathological processes, targeting MMP-2 for therapeutic purposes presents challenges due to its dual functions in tissue remodeling and repair, raising concerns about unplanned consequences such as impaired tissue healing or excessive tissue damage. These challenges underscore the need for future research to focus on developing selective modulators that can precisely balance their activity under specific disease environments. Clinical trials targeting MMP-2 modulation highlight the potential of gelatinase inhibitors, including those targeting MMP-2, to reduce tumor progression in fibrosarcoma, breast, and lung cancers. This paper reviews the structure, function, and regulation of MMP-2, its involvement in disease pathogenesis, and the potential challenges in the therapeutic implications of modulating its activity. Full article

Skin aging is intrinsic and extrinsic. Intrinsic, or chronological, skin aging is an inevitable process of chronological and physiological alterations. The factors contributing to extrinsic skin aging involve sunlight, nutrients, and stress. Thus, extrinsic aging is thought to be superimposed over intrinsic aging and depends on the intensity and duration of environmental exposure and skin type (e.g., dry skin, oily skin, or eczema). The most significant extrinsic aging factor is UV radiation, which causes cellular senescence in a process known as photoaging. This study aimed to illuminate the mechanism whereby solubilized elastin peptide lotion (EL) from the bulbus arteriosus of yellowtail (Seriola quinqueradiata) prevents skin photoaging in hairless mice. EL reduced wrinkle formation, epidermal skin thickness, and Ki67 (cell growth marker) mRNA expression in skin tissues from ultraviolet B (UVB)-irradiated mice. EL treatment also reduced glyoxalase-1 (key enzyme of glucose metabolism) levels in skin tissue. Although no significant differences in collagen and elastin contents were found in dermal areas, matrix metalloproteinase-12 (wrinkle-related marker) expression was reduced following EL application. Furthermore, skin DPP-IV/CD26 (new senescence marker) levels decreased following EL treatment in photoaging model mice. These results suggest that EL moderates skin damage caused by UVB irradiation by regulating senescence-related molecule expression. Full article

Mutations in IDH1 and TP53 have a significant impact on glioma prognosis and progression; however, their roles in tumor cell invasion in terms of interactions with particular components of the extracellular matrix (ECM) are still unclear. Using gene editing protocol based on CRISPR-Cas 9 with cytidine deaminase, we introduced point mutations into U87MG glioblastoma cells to establish modified cell lines with heterozygous IDH1 R132H, homozygous TP53 R248Q and heterozygous IDH1 R132H, homozygous TP53 R248Q genotypes. A comparative study of cell migration on major ECM components was carried out by high-content microscopy. IDH1 R132H mutation introduced to U87MG glioblastoma cells was shown to decrease the migration speed on Matrigel and collagen IV substrates compared to the wild-type. This data were supported by cell adhesion quantification via the lateral shift assay performed by atomic force microscopy (AFM). TP53 R248Q mutation increased cell adhesion to various substrates and significantly promoted cell migration on hyaluronic acid and chondroitin sulfate but did not change the migration rates on laminin and collagens IV and I. A double-mutant genotype produced by consequently introducing IDH1 R132H and TP53 R248Q to parental glioblastoma cells was characterized by the highest migration among all the cell lines, with particularly faster motility on chondroitin sulfate. These findings underscore the complex interactions between glioma cells, with the most important driver mutations and specific ECM components regulating cancer cell migration, offering valuable insights for potential therapeutic targets in glioma treatment. Full article