Extracellular Matrix Collagen Research Articles

Mimicking the Graded Wavy Structure of the Anterior Cruciate Ligament.

Anterior cruciate ligament (ACL) is the connective tissue providing mechanical stability to the knee joint. ACL reconstruction upon rupture remains a clinical challenge due to the high mechanical properties required for proper functioning. ACL owes its outstanding mechanical properties to the arrangement of the extracellular matrix (ECM) and to the cells with distinct phenotypes present along the length of the tissue. Tissue regeneration appears as an ideal alternative. In this study, a tri-phasic fibrous scaffold that mimics the structure of collagen in the native ECM is developed, presenting a wavy intermediate zone and two aligned uncurled extremes. The mechanical properties of the wavy scaffolds present a toe region, characteristic of the native ACL, and an extended yield and ultimate strain compared to aligned scaffolds. The presentation of a wavy fiber arrangement affects cell organization and the deposition of a specific ECM characteristic of fibrocartilage. Cells cultured in wavy scaffolds grow in aggregates, deposit an abundant ECM rich in fibronectin and collagen II, and express higher amounts of collagen II, X, and tenomodulin as compared to aligned scaffolds. In vivo implantation in rabbits shows a high cellular infiltration and the formation of an oriented ECM compared to aligned scaffolds.

Identification of a potential competing endogenous RNA (ceRNA) network in gastric adenocarcinoma.

Recently, a growing body of evidence has revealed the role of competing endogenous RNA (ceRNA) networks in various human cancers. However, there is still a lack of research on the systemic ceRNA network related to gastric adenocarcinoma. The intersection of differentially expressed genes (DEGs) was obtained by mining the GSE54129, GSE13861, and GSE118916 datasets from the Gene Expression Omnibus (GEO) website. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) was used for the enrichment analysis. A protein-protein interaction (PPI) network was established with the STRING online database, and hub genes were identified by Cytoscape software. The prediction of key microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) was conducted by miRNet. The prognostic analysis, expression difference, and correlation analysis of messenger RNAs (mRNAs), lncRNAs, and miRNAs were carried out using the Gene Expression Profiling Interactive Analysis (GEPIA), Kaplan-Meier plotter, and Encyclopedia of RNA Interactomes (ENCORI). We identified180 significant DEGs. Extracellular matrix (ECM) receptor interaction, focal adhesion, ECM tissue, and collagen catabolic processes were the most significant pathways in the functional enrichment analysis. Nineteen upregulated hub genes and one downregulated hub gene were found to be significantly associated with the prognosis of gastric adenocarcinoma. Of the 18 miRNAs targeting 12 key genes, only six were associated with a promising prognosis in gastric adenocarcinoma. By comprehensive differential expression and survival analysis, 40 key lncRNAs were identified. Finally, we constructed a network of 24 ceRNAs associated with gastric adenocarcinoma. Potential mRNA-miRNA-lncRNA subnets were constructed, each RNA of which can be used as a prognostic biomarker for gastric adenocarcinoma.

Dairy bioactives and functional ingredients with skin health benefits

The potential of whey from Italian cheese productions to support skin health and anti-ageing mechanism was studied. The effect of whey on dermal and epidermal cells was evaluated. Whey inhibited the activity of elastase and tyrosinase enzymes by 60% and 32%, respectively. Whey cytotoxicity against tested skin cell lines, human fibroblasts (HDFa) and keratinocytes (HaCaT) was not observed. Moreover, the antioxidant activity of the samples was noted, after treatment with whey intracellular ROS level was decreased by 87% in comparison with the hydrogen peroxide-treated cells. Fibroblasts produced a significant amount of extracellular matrix molecules, collagen I, elastin and glycosaminoglycans as a result of treatment with tested whey. In addition, the ability of samples to improve the cell barrier integrity of keratinocytes was proven. The obtained results indicate that pure whey supports skin health and shows potential to be used by the cosmetic industry.

The Impact of Phase-Specific Macrophage Depletion on Intestinal Anastomotic Healing.

Intestinal anastomotic healing (AH) is critical in colorectal surgery, since disruptive AH leads to anastomotic leakage, a feared postoperative complication. Macrophages are innate immune cells and are instrumental in orchestrating intestinal wound healing, displaying a functional dichotomy as effectors of both tissue injury and repair. The aim of this study was to investigate the phase-specific function and plasticity of macrophages during intestinal AH. Transgenic CD11b diphtheria toxin receptor (CD11b-DTR) mice were used to deplete intestinal macrophages in a temporally controlled manner. Distal colonic end-to-end anastomoses were created in CD11b-DTR, and wild-type mice and macrophages were selectively depleted during either the inflammatory (day 0-3), proliferative (day 4-10), or reparative (day 11-20) phase of intestinal AH, respectively. For each time point, histological and functional analysis as well as gene set enrichment analysis (GSEA) of RNA-sequencing data were performed. Macrophage depletion during the inflammatory phase significantly reduced the associated inflammatory state without compromising microscopic AH. When intestinal macrophages were depleted during the proliferative phase, AH was improved, despite significantly reduced perianastomotic neoangiogenesis. Lastly, macrophages were depleted during the reparative phase and GSEA revealed macrophage-dependent pathways involved in collagen remodeling, cell proliferation, and extracellular matrix composition. However, AH remained comparable at this late timepoint. These results demonstrate that during intestinal AH, macrophages elicit phase-specific effects, and that therapeutic interventions must critically balance their dual and timely defined role.

Metabolic dysfunction in obesity is related to impaired suppression of fatty acid release from adipose tissue by insulin.

The aims of this study were: 1) to assess relationships among insulin-mediated glucose uptake with standard clinical outcomes and deep-phenotyping measures (including fatty acid [FA] rate of appearance [FA Ra] into the systemic circulation); and 2) to examine the contribution of adipocyte size, fibrosis, and proteomic profile to FA Ra regulation. A total of 66 adults with obesity (BMI=34 [SD 3] kg/m2 ) were assessed for insulin sensitivity (hyperinsulinemic-euglycemic clamp), and stable isotope dilution methods quantified glucose, FA, and glycerol kinetics in vivo. Abdominal subcutaneous adipose tissue (aSAT) and skeletal muscle biopsies were collected, and magnetic resonance imaging quantified liver and visceral fat content. Insulin-mediated FA Ra suppression associated with insulin-mediated glucose uptake (r=0.51; p < 0.01) and negatively correlated with liver (r=-0.36; p < 0.01) and visceral fat (r=-0.42; p < 0.01). aSAT proteomics from subcohorts of participants with low FA Ra suppression (n=8) versus high FA Ra suppression (n=8) demonstrated greater extracellular matrix collagen protein in low versus high FA Ra suppression. Skeletal muscle lipidomics (n=18) revealed inverse correlations of FA Ra suppression with acyl-chain length of acylcarnitine (r=-0.42; p=0.02) and triacylglycerol (r=-0.51; p < 0.01), in addition to insulin-mediated glucose uptake (acylcarnitine: r=-0.49; p < 0.01, triacylglycerol: r=-0.40; p < 0.01). Insulin's ability to suppress FA release from aSAT in obesity is related to enhanced insulin-mediated glucose uptake and metabolic health in peripheral tissues.

Post-myocardial infarction fibrosis: Pathophysiology, examination, and intervention.

Cardiac fibrosis plays an indispensable role in cardiac tissue homeostasis and repair after myocardial infarction (MI). The cardiac fibroblast-to-myofibroblast differentiation and extracellular matrix collagen deposition are the hallmarks of cardiac fibrosis, which are modulated by multiple signaling pathways and various types of cells in time-dependent manners. Our understanding of the development of cardiac fibrosis after MI has evolved in basic and clinical researches, and the regulation of fibrotic remodeling may facilitate novel diagnostic and therapeutic strategies, and finally improve outcomes. Here, we aim to elaborate pathophysiology, examination and intervention of cardiac fibrosis after MI.

Fibrosis-associated DDR1 downregulation contributes to a better prognosis in oral squamous cell carcinoma associated with oral submucous fibrosis

Betel quid-associated oral submucous fibrosis (OSMF) and its malignant transformation to oral squamous cell carcinoma (OSCC) is common in Asian countries. Oral squamous cell carcinoma associated with oral submucous fibrosis (OSCC-OSMF) carries burden of increased fibrosis in the extracellular matrix at intra-tumoral and peri-tumoral locations. Literature reports that OSCC-OSMF shows better grade of tumor differentiation and have lesser chance of metastasis with good survival rate. However, there is still a deficit in the proper justification for reduced metastasis and good survival of OSCC-OSMF entity. In this paper, we hypothesize the role of discoidin domain receptor-1 (DDR1) and fibrosis in executing better prognosis in OSCC-OSMF. A detailed mechanism of action by considering presence of intact type 1 collagen (COL1) in OSCC-OSMF extracellular matrix and decreased DDR1 receptor expression on tumor cells and associated downregulation of NF-κB-p62-NRF2 signaling. The proposed hypothesis addresses the unresolved research question related to prognostic heterogeneity between OSCC-OSMF and OSCC without OSMF cases. Moreover, it will help in customization of the future DDR1 associated targeted therapy in OSCC.

Topical Application of Peptide Nucleic Acid Antisense Oligonucleotide for MMP-1 and Its Potential Anti-Aging Properties

Matrix metalloproteinase-1 (MMP-1) is a zinc-containing endopeptidase that degrades dermal collagen and other extracellular matrix molecules. It is recognized as one of the most important indicators of cellular senescence and age-related skin changes. Here, we introduced a novel MMP-1 peptide nucleic acid (PNA) derivative-PNA-20 carboxyethyl fluorene (CEF)-which can interact with and consequently silence the MMP-1 gene sequence. The investigation on the efficacy of PNA-20 CEF in MMP-1 silencing in human dermal fibroblasts revealed significantly decreased expression of MMP-1 at both gene and protein levels. Treatment with PNA-20 CEF showed significantly increased expression of collagen I protein, indicating its potential role in preventing the degradation of collagen I and consequently combating the skin aging process. Its topical application on 3D human skin tissue showed successful absorption into the epidermis and the upper dermis. Furthermore, the additional 4-week single-arm prospective study on 21 Asian women revealed improvements in facial wrinkles, skin moisture, elasticity, and density after the use of the topical PNA-20 CEF cosmeceutical formulation. Additional in-vitro and ex-vivo studies are needed for a comprehensive understanding of the skin anti-aging effects of MMP-1 PNA.

Long-term cadmium exposure induces chronic obstructive pulmonary disease-like lung lesions in a mouse model

Accumulating evidences demonstrate that long-term exposure to atmospheric fine particles and air pollutants elevates the risk of chronic obstructive pulmonary disease (COPD). Cadmium (Cd) is one of the important toxic substances in atmospheric fine particles and air pollutants. In this study, we aimed to establish a mouse model to evaluate whether respiratory Cd exposure induces COPD-like lung injury. Adult male C57BL/6 mice were exposed to CdCl2 (10 mg/L, 4 h per day) by inhaling aerosol for either 10 weeks (short-term) or 6 months (long-term). The mean serum Cd concentration was 6.26 μg/L in Cd-exposed mice. Lung weight and coefficient were elevated in long-term Cd-exposed mice. Pathological scores and alveolar destructive indices were increased in long-term Cd-exposed mouse lungs. Mean linear intercept and airway wall thickness were accordingly elevated in Cd-exposed mice. Inflammatory cell infiltration was obvious and inflammatory cytokines, including TNF-α, IL-1β, IL-6, IL-8, IL-10 and TGF-β, were up-regulated in Cd-exposed mouse lungs. α-SMA, N-cadherin and vimentin, epithelial-mesenchymal transition markers, and extracellular matrix collagen deposition around small airway, determined by Masson's trichrome staining, were shown in Cd-exposed mouse lungs. COPD-characteristic lung function decline was observed in long-term Cd-exposed mice. These outcomes show that long-term respiratory exposure to Cd induces COPD-like lung lesions for the first time.

Extracellular matrix collagen biomarker levels in patients who underwent pulmonary endarterectomy.

The role of extracellular matrix collagen biomarkers in chronic thromboembolic pulmonary hypertension (CTEPH) is not well known. Our goal was to investigate the matrix metalloproteinase (MMP)-2 and -9 protein levels in patients with CTETH. This is a prospective, cross-sectional study. Patients with CTETH who underwent pulmonary endarterectomy comprise group 1, and the control group included patients who underwent lung surgery without pulmonary hypertension (group 2) between March 2020 and March 2021. In addition to serum levels of MMP-9, the pulmonary endarterectomy and control pulmonary artery tissue samples were measured by the enzyme-linked immunosorbent assay 4pl, cubic, quadratic and Western blot techniques. Levels of MMP-2, which consist of pro MMP-2/ß-actin and active MMP-2/ß-actin and MMP-9/ß-actin, were measured only in the tissue samples. Forty-eight patients were enrolled consecutively in group 1 (n: 24) and group 2 (n: 24). The serum concentrations of MMP-9 were similar in both groups. Similarly, a comparison of tissue sample levels of pro MMP-2/ß-actin (P = 0.496) and active MMP-2/ß-actin (P = 0.216) showed no significant difference between the groups. The tissue samples from patients with CTETH had significantly lower amounts of MMP-9/ß-actin compared to the control group (P = 0.001). This study indicates that serum levels of extracellular matrix collagen biomarkers were similar in patients with CTETH who were candidates for surgery and in patients who had non-pulmonary hypertension who underwent lung surgery. Differences in levels of MMP-9/ß-actin in tissue samples may play a role in pulmonary vascular remodelling in operable patients.

Extracellular Matrix-Derived Biophysical Cues Mediate Interstitial Flow-Induced Sprouting Angiogenesis.

Sprouting angiogenesis is orchestrated by an intricate balance of biochemical and mechanical cues in the local tissue microenvironment. Interstitial flow has been established as a potent regulator of angiogenesis. Similarly, extracellular matrix (ECM) physical properties, such as stiffness and microarchitecture, have also emerged as important mediators of angiogenesis. However, the interplay between interstitial flow and ECM physical properties in the initiation and control of angiogenesis is poorly understood. Using a three-dimensional (3D) microfluidic tissue analogue of angiogenic sprouting with defined interstitial flow superimposed over ECM with well-characterized physical properties, we found that the addition of hyaluronan (HA) to collagen-based matrices significantly enhances sprouting induced by interstitial flow compared to responses in collagen-only hydrogels. We confirmed that both the stiffness and matrix pore size of collagen-only hydrogels were increased by the addition of HA. Interestingly, interstitial flow-potentiated sprouting responses in collagen/HA matrices were not affected when functionally blocking the HA receptor CD44. In contrast, enzymatic depletion of HA in collagen/HA matrices with hyaluronidase (HAdase) resulted in decreased stiffness, pore size, and interstitial flow-mediated sprouting to the levels observed in collagen-only matrices. Taken together, these results suggest that HA enhances interstitial flow-mediated angiogenic sprouting through its alterations to collagen ECM stiffness and pore size.

A47 THE GUT MICROBIOTA INFLUENCES COLONIC HEALING AFTER SURGERY IN PATIENTS UNDERGOING BOWEL RESECTION FOR COLORECTAL CANCER

Abstract Background The standard treatment of colorectal cancer (CRC) consists of a surgical resection of the colonic segment with the tumor, followed by a reconnection of the remaining bowel ends, or "anastomosis". The anastomosis may fail to heal in up to 20% of patients, which leads to anastomotic leak, a major complication that increases postoperative morbidity and mortality. This complication is unpredictable and its causes remain poorly understood. Purpose The objective of this study is to investigate the possible role of the gut microbiome in anastomotic healing after surgery in patients with CRC. Method We collected preoperative fecal samples and intraoperative mucosal samples from CRC patients undergoing surgery with anastomosis. The gut microbiota of patients with AL and of others that presented optimal healing after surgery was analyzed and compared using the Anchor 16S pipeline. To assess the role of the patients' microbiota in healing, fecal microbiota transplantation (FMT) was performed in mice using preoperative fecal samples from CRC patients with and without AL. Mice were then subjected to colonic surgery using a colonic anastomosis model. Six days after surgery, anastomotic healing was assessed macroscopically and microscopically. The gut barrier function was also assessed. The gut microbiota composition was compared between the groups colonized with samples from patients with and without AL to detect potential differences. Result(s) Mice colonized by FMT with the microbiota of donors with AL displayed poor anastomotic healing macroscopically, and a weaker wound microscopically. These same mice displayed a weaker gut barrier, as objectified by higher bacterial translocation to the spleen. The anastomoses of mice receiving the microbiota of AL donors displayed lower concentrations of collagen and fibronectin and higher inflammatory cytokines and collagenolytic enzymes, indicating poor extracellular matrix formation and collagen degradation locally.The beta-diversity of the gut microbiota was significantly different between mice receiving the microbiota of donors with and without AL, and several bacterial species were differentially abundant between the two groups. Conclusion(s) The preoperative gut microbiota in CRC patients who experience anastomotic leak after surgery induces poor anastomotic healing in mice and a weaker gut barrier after colonic surgery. Several bacterial species were found to be associated with the healing process. Please acknowledge all funding agencies by checking the applicable boxes below CIHR, Other Please indicate your source of funding; NSERC, FRQS, New Frontiers in Research, Montreal Cancer Institute. Disclosure of Interest None Declared

Autoimmune Hepatitis and Fibrosis

Autoimmune hepatitis (AIH) is a chronic immune-inflammatory disease of the liver, generally considered a rare condition. The clinical manifestation is extremely varied and can range from paucisymptomatic forms to severe hepatitis. Chronic liver damage causes activation of hepatic and inflammatory cells leading to inflammation and oxidative stress through the production of mediators. This results in increased collagen production and extracellular matrix deposition leading to fibrosis and even cirrhosis. The gold standard for the diagnosis of fibrosis is liver biopsy; however, there are serum biomarkers, scoring systems, and radiological methods useful for diagnosis and staging. The goal of AIH treatment is to suppress fibrotic and inflammatory activities in the liver to prevent disease progression and achieve complete remission. Therapy involves the use of classic steroidal anti-inflammatory drugs and immunosuppressants, but in recent years scientific research has focused on several new alternative drugs for AIH that will be discussed in the review.

IL-18-mediated neutrophil recruitment promotes acute lung injury in inflammation-mediated chronic pancreatitis.

Lung injury is the most common secondary complication of pancreatitis and pancreatic malignancy. Around 60-70% of pancreatitis-related deaths are caused by lung injury; however, there is no animal model of the inflammation-mediated progressive pulmonary pathological events that contribute to acute lung injury in chronic pancreatitis (CP). Hence, we developed an inflammation-mediated mouse model and studied the pathological events that have a critical role in promoting the pathogenesis of lung injury. Our proteomic analysis of lung tissue revealed neutrophil-associated induction of neutrophil gelatinase-associated lipocalin (NGAL) and myeloperoxidase enzyme, further supporting a role for neutrophils in promoting IL-18-associated lung injury. We show that neutrophils released IL-18-induced p-NF-κB along with profibrotic and oncogenic proteins like TTF1, PDX1, and SOX9 in lung tissues of a mouse model of chronic pancreatitis. We also show that neutrophil infiltration induces TGF-β and SMAD4 and activates epithelial cells to produce other profibrotic proteins like ZO-1 and MUC2, along with the fibroblast markers FGF-1 and αSMA, that cause mesenchymal transition and accumulation of extracellular matrix collagen. Most importantly, we present evidence that IL-18 inhibition significantly alleviates CP-induced lung injury. This was further established by the finding that IL-18 gene-deficient mice showed improved lung injury by inhibition of TGF-β and fibroblast to mesenchymal transition and reduced collagen accumulation. The present study suggests that inhibition of IL-18 may be a novel treatment for CP-associated induced acute lung injury.

Overlapping between Wound Healing Occurring in Tumor Growth and in Central Nervous System Neurodegenerative Diseases

Wound healing is characterized by the formation of a granulation tissue consisting of inflammatory cells, newly formed blood vessels, and fibroblasts embedded in a loose collagenous extracellular matrix. Tumors behave as wounds that fail to heal. Neuronal loss in neurodegenerative disease is associated with the synthesis and release of new components of the extracellular matrix by activated fibroblasts and astrocytes. This condition is responsible for a perpetuation of the wound healing state and constitutes a condition very similar to that which occurs during tumor progression. The aim of this article is to emphasize and compare the role of wound healing in two different pathological conditions, namely tumor growth and central nervous system neurodegenerative diseases. Both are conditions in which wounds fail to heal, as occurs in physiological conditions.

Treatment with semaglutide, a GLP-1 receptor agonist, improves extracellular matrix remodeling in the pancreatic islet of diet-induced obese mice

AimsThe extracellular matrix (ECM) is fundamental for the normal endocrine functions of pancreatic islet cells and plays key roles in the pathophysiology of type 2 diabetes. Here we investigated the turnover of islet ECM components, including islet amyloid polypeptide (IAPP), in an obese mouse model treated with semaglutide, a glucagon-like peptide type 1 receptor agonist. Main methodsMale one-month-old C57BL/6 mice were fed a control diet (C) or a high-fat diet (HF) for 16 weeks, then treated with semaglutide (subcutaneous 40 μg/kg every three days) for an additional four weeks (HFS). The islets were immunostained and gene expressions were assessed. Key findingsComparisons refer to HFS vs HF. Thus, IAPP immunolabeling and beta-cell-enriched beta-amyloid precursor protein cleaving enzyme (Bace2, −40 %) and heparanase immunolabeling and gene (Hpse, −40 %) were mitigated by semaglutide. In contrast, perlecan (Hspg2, +900 %) and vascular endothelial growth factor A (Vegfa, +420 %) were enhanced by semaglutide. Also, semaglutide lessened syndecan 4 (Sdc4, −65 %) and hyaluronan synthases (Has1, −45 %; Has2, −65 %) as well as chondroitin sulfate immunolabeling, and collagen type 1 (Col1a1, −60 %) and type 6 (Col6a3, −15 %), lysyl oxidase (Lox, −30 %) and metalloproteinases (Mmp2, −45 %; Mmp9, −60 %). SignificanceSemaglutide improved the turnover of islet heparan sulfate proteoglycans, hyaluronan, chondroitin sulfate proteoglycans, and collagens in the islet ECM. Such changes should contribute to restoring a healthy islet functional milieu and should reduce the formation of cell-damaging amyloid deposits. Our findings also provide additional evidence for the involvement of islet proteoglycans in the pathophysiology of type 2 diabetes.

Developmental Changes in Patterns of Distribution of Fibronectin and Tenascin-C in the Chicken Cornea: Evidence for Distinct and Independent Functions during Corneal Development and Morphogenesis.

The cornea forms the tough and transparent anterior part of the eye and by accurate shaping forms the major refractive element for vision. Its largest component is the stroma, a dense collagenous connective tissue positioned between the epithelium and the endothelium. In chicken embryos, the stroma initially develops as the primary stroma secreted by the epithelium, which is then invaded by migratory neural crest cells. These cells secrete an organised multi-lamellar collagenous extracellular matrix (ECM), becoming keratocytes. Within individual lamellae, collagen fibrils are parallel and orientated approximately orthogonally in adjacent lamellae. In addition to collagens and associated small proteoglycans, the ECM contains the multifunctional adhesive glycoproteins fibronectin and tenascin-C. We show in embryonic chicken corneas that fibronectin is present but is essentially unstructured in the primary stroma before cell migration and develops as strands linking migrating cells as they enter, maintaining their relative positions as they populate the stroma. Fibronectin also becomes prominent in the epithelial basement membrane, from which fibronectin strings penetrate into the stromal lamellar ECM at right angles. These are present throughout embryonic development but are absent in adults. Stromal cells associate with the strings. Since the epithelial basement membrane is the anterior stromal boundary, strings may be used by stromal cells to determine their relative anterior-posterior positions. Tenascin-C is organised differently, initially as an amorphous layer above the endothelium and subsequently extending anteriorly and organising into a 3D mesh when the stromal cells arrive, enclosing them. It continues to shift anteriorly in development, disappearing posteriorly, and finally becoming prominent in Bowman's layer beneath the epithelium. The similarity of tenascin-C and collagen organisation suggests that it may link cells to collagen, allowing cells to control and organise the developing ECM architecture. Fibronectin and tenascin-C have complementary roles in cell migration, with the former being adhesive and the latter being antiadhesive and able to displace cells from their adhesion to fibronectin. Thus, in addition to the potential for associations between cells and the ECM, the two could be involved in controlling migration and adhesion and subsequent keratocyte differentiation. Despite the similarities in structure and binding capabilities of the two glycoproteins and the fact that they occupy similar regions of the developing stroma, there is little colocalisation, demonstrating their distinctive roles.

Construction of chemoreactive heterogeneous nanofibers through strategic coassembly of different proteins

In nature, hierarchically ordered supramolecular assemblies built from protein building blocks become key elements in the composition of both functional nanostructures such as collagens in extracellular matrix, biofilm matrix, and pathological nanostructures including amyloid deposits. Hence, the construction of multiprotein nanoarchitecture is an important research target for innovations in the designing of bioactive nanomaterials. Although β-strand-template-mediated coassembly/cross-seeding of diverse proteins have been reported, the structural and catalytic characteristics of the resultant heterogeneous nanofibers remain largely unknown. Here, we demonstrate the genesis of stable and chemoreactive multiprotein nanofibers via kinetically favored coassembly of diverse proteins with low sequence similarity (insulin, serum albumin, cytochrome c, lysozyme, β-lactoglobulin). The multiprotein-nanofibers contained β-sheet-rich amyloid-like conformers, and we find that gain of charge-complementarity and H-bond-promoting sticky-groups are crucial for fabricating heterogeneous nanofibers. Unlike self-assembly, a lower activation energy barrier was observed for coassembly process, and coaggregation rates increased with increasing degree of heterogeneity in protein mixture. The heterogeneous nanofibers exhibit surface-catalyzing property by hastening dopamine oxidation and triggering amyloid-cross-seeding of diverse proteins, and we also observed their cellular internalization and cytotoxic effect. Our results provide experimental and conceptual foundations for the construction of protein-based hybrid nanomaterials relevant to both biological and material science research.

Prognostic and immunological role of alpha-L-fucosidase 2 (FUCA2) in hepatocellular carcinoma.

This study investigated the prognostic and immunological significance of alpha-L-fucosidase 2 (FUCA2) in hepatocellular cancer (HCC). The expression of FUCA2 and its clinical and prognostic values were explored across several databases, namely the University of Alabama Cancer Database, The Cancer Genome Atlas, Gene Expression Profiling Interactive Analysis, and the Human Protein Atlas. The prognostic relevance of FUCA2 was investigated using Kaplan-Meier curves, nomograms, and Cox analysis. The "limma" package in R was used to identify differentially expressed genes between high and low FUCA2 expression. A protein interaction network was established using the Search Tool for the Retrieval of Interacting Genes (STRING), whereas hub genes and clustering modules were identified using Cytoscape. "clusterProfiler", an R package, was used to examine the potential function of FUCA2. Using gene set enrichment analysis, signaling pathways associated with FUCA2 expression were identified. Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT), Tumor Immune Estimation Resource (TIMER) 2.0, and Tumor and Immune System Interaction Database (TISIDB) were used to examine immune infiltration and FUCA2 in HCC. Many datasets indicated that FUCA2 expression is higher in HCC, and that this is related to age and overall survival (OS). With the cutoff value of 50% as the dividing threshold, the patients were divided into a high-FUCA2 expression group (n=167) and a low-FUCA2 expression group (n=168). High levels of FUCA2 expression coincided with decreased OS. FUCA2 expression in HCC was associated with immune infiltrates. The functional mechanisms of FUCA2 depend on signal release, extracellular matrix collagen, and neuroactive ligands and receptors. In HCC, increased FUCA2 expression is associated with a poor prognosis and immune infiltration. FUCA2 may serve as an immunological and predictive biomarker for HCC.

Neutrophil Elastase in the Pathogenesis of Chronic Obstructive Pulmonary Disease: A Review

Abstract: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality globally. It is associated with a low quality of life and socio-economic burden. Airway destruction in COPD pathogenesis is primarily due to the three mechanisms: protease-antiprotease imbalance, chronic airway inflammation, and oxidative stress, which is triggered by exposure to harmful particles, such as cigarette smoking. Neutrophil elastase (NE), a serine protease stored in azurophilic granules of neutrophils, actively participates in airway remodeling and microbiocidal activity. It hydrolyzes elastin, collagen, and other vital extracellular matrix proteins (EMP) in the respiratory tissue. In addition, neutrophil elastase activates other principal proteinases such as matrix metalloprotease (MMP)-2, MMP-9, Cathepsin B, Meprin α protease, and Calpain that amplify EMP degradation. Macrophage, the primary leukocyte, responsible for lung parenchymal inflammation in COPD, is also activated by NE. However, neutrophil elastase level is positively correlated with the degree of airway inflammation and disease severity. Neutrophil elastase activates reactive oxygengenerating systems such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and myeloperoxidase and it also generates mitochondrial-derived-reactive oxygen species formation by inducing the secretion of Interleukin (IL)-1 andTumour necrosis factor (TNF)- α. In addition, neutrophil elastase stimulates respiratory cell apoptosis by direct (e.g., activating the caspase-3 pathway) and indirect mechanisms (e.g., by secretion of Neutrophil Extracellular Traps). Surprisingly, neutrophil elastase may have small anti-inflammatory properties. In conclusion, neutrophil elastase is one of the main culprits responsible for COPD pathogenesis by mediating the activation of Triad COPD pathogenesis.