Search Results (46)

Chronic hydrocephalus following aneurysmal subarachnoid hemorrhage (SAH) is a complication that can lead to deterioration in neurological status and cognitive impairment. Our recent clinical study reported that a high concentration of plasma fibulin-5 (FBLN5), a matricellular protein, was associated with the occurrence of chronic hydrocephalus after SAH. This study aimed to investigate whether and how FBLN5 was associated with hydrocephalus during acute to later phases of SAH in mice. C57BL/6 male mice underwent sham or filament perforation SAH modeling, and vehicle or two dosages (0.01 and 0.1 μg) of short or long recombinant FBLN5 (rFBLN5) were randomly administrated by an intracerebroventricular injection. Neurobehavioral tests, measurements of the degree of ventricular enlargement, Western blotting, and immunohistochemical staining were performed to evaluate hydrocephalus 24 and 48 h after SAH. After SAH, ventricular dilatation did not occur at 24 h but developed at 48 h, and both doses of long rFBLN5 with an arginine–glycine–aspartic acid domain suppressed ventricular dilatation at 48 h after SAH. Long rFBLN5 also decreased phosphorylated p38 in the brain parenchyma and prevented post-SAH increases in perivascular macrophages, as well as microglia activation in the brain parenchyma at 48 h after SAH. Although further research is required to clarify the detailed mechanism, this study demonstrated for the first time that exogenous administration of FBLN5 may have a protective effect against ventricular dilatation after experimental SAH. Full article

Nannochloropsis oceanica and Chlorococcum amblystomatis exhibit significant potential for protecting skin cells from oxidative stress-induced metabolic dysfunctions, owing to their high bioactive lipid content. This study aimed to evaluate their cytoprotective effects on the ultraviolet A (UVA)-perturbed proteome of 3D-cultured skin fibroblasts, using high-throughput proteomics. Chlorococcum amblystomatis lipid extract promoted a reduction in UVA-induced cytochrome c oxidase subunit 4 isoform 1 and cell death protein 6 levels, alongside the restoration of ferritin light chain expression diminished by UVA. It downregulated the expression of ubiquitin-conjugating enzyme E2 and lactoylglutathione lyase, which were upregulated by UVA. Furthermore, the elevated superoxide dismutase [Mn] mitochondrial levels in the caspase-1 interactome emphasized the lipid extract’s role in mitigating oxidative stress-associated chronic inflammation by regulating caspase-1 activity. In addition to this notable redox balance-regulating and cytoprotective activity, conversely, the protein inflammation signaling mediated by UVA was regulated in terms of wound healing potential in the case of Nannochloropsis oceanica lipid extract. Following UVA radiation, it promoted the upregulation of complement component B, thrombospondin-1, MMP1, and fibulin-1. The results revealed that both lipid extracts effectively reversed the UVA-perturbed proteomic profile of fibroblasts, highlighting their therapeutic potential in protecting the skin from UV radiation. Full article

Transforming Growth Factor-Beta 1 (TGF-β1) plays a pivotal role in the differentiation of fibroblasts into myofibroblasts, which is a critical process in tissue repair, fibrosis, and wound healing. Upon exposure to TGF-β1, fibroblasts acquire a contractile phenotype and secrete collagen and extracellular matrix components. Numerous studies have identified hydrogen peroxide (H₂O₂) as a key downstream effector of TGF-β1 in this pathway. H₂O₂ functions as a signalling molecule, regulating various cellular processes mostly through post-translational redox modifications of cysteine thiol groups of specific proteins. In this study, we used primary human skin fibroblast cultures to investigate the oxidative mechanisms triggered by TGF-β1. We analyzed the expression of redox-related genes, evaluated the effects of the genetic and pharmacological inhibition of H₂O₂-producing enzymes, and employed an unbiased redox proteomics approach (OxICAT) to identify proteins undergoing reversible cysteine oxidation. Our findings revealed that TGF-β1 treatment upregulated the expression of oxidant-generating genes while downregulating antioxidant genes. Low concentrations of diphenyleneiodonium mitigated myofibroblast differentiation and mitochondrial oxygen consumption, suggesting the involvement of a flavoenzyme in this process. Furthermore, we identified the increased oxidation of highly conserved cysteine residues in key proteins such as the epidermal growth factor receptor, filamin A, fibulin-2, and endosialin during the differentiation process. Collectively, this study provides insights into the sources of H₂O₂ in fibroblasts and highlights the novel redox mechanisms underpinning fibroblast-to-myofibroblast differentiation. Full article

Dupuytren’s contracture belongs to a group of fibrotic diseases that have similar mechanisms but lack effective treatment and prevention options. The excessive accumulation of connective tissue in Dupuytren’s disease leads to palmar fibrosis that results in contracture deformities. The present study aimed to investigate how the tissue microenvironment in Dupuytren’s contracture affects the phenotypic differentiation of macrophages, which leads to an inflammatory response and the development of chronicity in fibrotic disease. We utilized a decellularization-based method combined with proteomic analysis to identify shifts in extracellular matrix composition and the surrounding tissue microenvironment. We found that the expression of several matricellular proteins, such as MFAP4, EFEMP1 (fibulin-3), and ANGPTL2, was elevated in Dupuytren’s tissue. We show that, in response to the changes in the extracellular matrix of Dupuytren’s contracture, macrophages regulate the fibrotic process by cytokine production, promote myofibroblast differentiation, and increase the fibroblast migration rate. Moreover, we found that the extracellular matrix of Dupuytren’s contracture directly supports the macrophage-to-myofibroblast transition, which could be another contributor to Dupuytren’s disease pathogenesis. Our results suggest that interactions between macrophages and the extracellular matrix should be considered as targets for novel fibrotic disease treatment and prevention strategies in the future. Full article

The FBLN1 gene encodes the fibulin-1 protein, the first member of the ECM glycoprotein family, and is crucial for embryonic development and organ tissue formation in mammals. Our previous transcriptome analysis identified the FBLN1 gene and suggested its potential role in influencing slaughter traits by regulating ECM function. This study aims to uncover key genetic variants (InDel and CNV) within the FBLN1 gene and examine its relationship with slaughter traits in beef cattle. In this study, the beef cattle genetic resources population Gaoqing black cattle were selected (n = 641), leading to the identification of three polymorphic InDel loci (13 bp insertion, 28 bp insertion, and 24 bp insertion) and two CNVs. Association analysis revealed that InDel polymorphisms in Gaoqing black cattle were significantly correlated with certain slaughter traits (p < 0.05), such as left limb weight and right limb weight. In addition, the CNV loci were significantly correlated with traits such as skirt steak and round small intestine (p < 0.05), and reached extremely significant levels (p < 0.01) in certain traits such as chunky II and high rib. In summary, the identified InDel and CNV polymorphisms in the FBLN1 gene represent potential molecular markers associated with slaughter traits in Gaoqing black cattle. These findings provide valuable insights for marker-assisted selection to enhance genetic improvement in beef cattle breeding. Full article

The present work shows that the exposure of mesothelial cells to simulated microgravity changes their cytoskeleton and adhesion proteins, leading to a cell switch from normal towards tumoral cells. Immunohistochemical and molecular data were obtained from both MeT-5A exposed to simulated microgravity and BR95 mesothelioma cell lines. Simulated microgravity was found to affect the expression of actin, vinculin, and connexin-43, altering their quantitative and spatial distribution pattern inside the cell. The analysis of the tumoral markers p27, CD44, Fibulin-3, and NANOG and the expression of genes related to cancer transformation such as NANOG, CDH-1, and Zeb-1 showed that the simulated microgravity environment led to expression patterns in MeT-5A cells similar to those observed in BR95 cells. The alteration in both quantitative expression and structural organization of the cytoskeleton and adhesion/communication proteins can thus be considered a pivotal mechanism involved in the cellular shift towards tumoral progression. Full article

Alzheimer’s disease (AD) is characterized by progressive cognitive decline and late-stage neurobehavioral issues marked by amyloid-beta plaques and Tau protein tangles. This study aims to investigate Fibulin-1(FBLN1) gene expression in the hippocampal tissue of Presenilin-1/Presenilin-2 conditional double-knockout (DKO) and double-transgenic (DTG) mice, using single-cell sequencing and experimental methods to verify abnormal methylation status and correlation with AD. Genomic DNA from DKO and DTG mice was used for genotyping. Reduced Representation Bisulfite Sequencing (RRBS) identified 10 genes with abnormal methylation changes, with protein–protein interaction (PPI) analysis highlighting five core genes, including FBLN1. Single-cell sequencing, RT-PCR, and Western blotting (WB) were used to analyze FBLN1 mRNA and protein levels in the hippocampal tissues of early-stage and mid-stage AD DKO, DTG, and CBAC57 mice. RRBS identified 10 genes with abnormal methylation, with PPI highlighting five core genes. Single-cell sequencing showed significant FBLN1 expression in AD groups. RT-PCR and WB indicated elevated FBLN1 mRNA and protein levels in mid-stage AD DKO and DTG mice compared to CBAC57 mice, with no differences in early-stage AD DKO and CBAC57 mice. RRBS revealed hypomethylation of the FBLN1 gene in mid-stage AD DKO mice. Elevated FBLN1 expression in AD models suggests an age-dependent neurodegenerative mechanism independent of amyloid-beta deposition. This study enhances our understanding of AD’s epigenetic mechanisms, which will aid targeted diagnosis, treatment, and prognosis. Full article

This study examined the patterns of epidermal growth-factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) deposition in the small intestine and colon to evaluate the association between the histopathological severity of EFEMP1 deposition and constipation and determine the colocalization of amyloid transthyretin (ATTR) and EFEMP1 deposits. In 40 older cases (≥80 years of age), EFEMP1 deposition in the small intestine initiated in the submucosal and subserous vessels, subserous interstitium, and serosa (early stage), progressing to the muscularis propria and peri-Auerbach plexus area (intermediate stage), and finally spreading diffusely to other areas, excluding the mucosa and muscularis mucosa (advanced stage). The colon had a similar pattern of progression. During the middle-to-advanced stages, amyloid formation was observed in some vascular and serous deposits. A subgroup of cases was identified in which EFEMP1 deposition was the only presumed cause of constipation. Additionally, we demonstrated the colocalization of ATTR and EFEMP1 deposition. Apple-green birefringence was detected under polarized light only in approximately one-half of the cases in the small intestine and one-third of the cases in the colon. These findings strongly suggest that EFEMP1 deposits are correlated with pathological conditions of the lower gastrointestinal tract. As the histopathological diagnosis using Congo red-stained specimens is challenging, the combined use of elastic fiber staining and EFEMP1 immunohistochemistry is recommended to identify EFEMP1 deposition. Full article

This study investigates the impact of Epstein–Barr virus (EBV) infection on children’s proteomes across different phases of the disease, utilising seventy-nine blood samples categorised into three groups: EBV-naive patients, acute infectious mononucleosis (IM) cases, and convalescents followed up for 12 months post-IM. The aim is to identify proteins influenced by EBV infection, shedding light on the chronic processes triggered by the virus. The results reveal thirty-nine proteins distinguishing between naive patients and those with IM, including actin, lumican, peroxiredoxin-2, fibulin-1, gelsolin, and alpha-2-macroglobulin, which are involved in immune responses, cell adhesion, and inflammation. Elevated oxidative stress markers like peroxiredoxin-2 in IM patients suggest potential links to EBV’s induction of reactive oxygen species. Increased levels of apolipoproteins A-I, A-IV, C-IV, and M during IM imply associations with viral infection, while complement system proteins (C1q, C1r, and C8 gamma chain) are also elevated, reflecting their role in the immune response and viral clearance. This study’s focus on children provides unique insights into EBV’s impact on young populations, emphasising proteomics’ role in uncovering protein associations and understanding the virus’s long-term consequences. However, specific relationships between identified proteins and EBV infection require further investigation. Full article

The process of aging is intimately linked to alterations at the tissue and cellular levels. Currently, the role of senescent cells in the tissue microenvironment is still being investigated. Despite common characteristics, different cell populations undergo distinctive morphofunctional changes during senescence. Mesenchymal stem cells (MSCs) play a pivotal role in maintaining tissue homeostasis. A multitude of studies have examined alterations in the cytokine profile that determine their regulatory function. The extracellular matrix (ECM) of MSCs is a less studied aspect of their biology. It has been shown to modulate the activity of neighboring cells. Therefore, investigating age-related changes in the MSC matrisome is crucial for understanding the mechanisms of tissue niche ageing. This study conducted a broad proteomic analysis of the matrisome of separated fractions of senescent MSCs, including the ECM, conditioned medium (CM), and cell lysate. This is the first time such an analysis has been conducted. It has been established that there is a shift in production towards regulatory molecules and a significant downregulation of the main structural and adhesion proteins of the ECM, particularly collagens, fibulins, and fibrilins. Additionally, a decrease in the levels of cathepsins, galectins, S100 proteins, and other proteins with cytoprotective, anti-inflammatory, and antifibrotic properties has been observed. However, the level of inflammatory proteins and regulators of profibrotic pathways increases. Additionally, there is an upregulation of proteins that can directly cause prosenescent effects on microenvironmental cells (SERPINE1, THBS1, and GDF15). These changes confirm that senescent MSCs can have a negative impact on other cells in the tissue niche, not only through cytokine signals but also through the remodeled ECM. Full article

Interaction between extracellular matrix (ECM) components plays an important role in the regulation of cellular behavior and hence in tissue function. Consequently, characterization of new interactions within ECM opens the possibility of studying not only the functional but also the pathological consequences derived from those interactions. We have previously described the interaction between fibulin2 and ADAMTS-12 in vitro and the effects of that interaction using cellular models of cancer. Now, we generate a mouse deficient in both ECM components and evaluate functional consequences of their absence using different cancer and inflammation murine models. The main findings indicate that mice deficient in both fibulin2 and ADAMTS12 markedly increase the development of lung tumors following intraperitoneal urethane injections. Moreover, inflammatory phenotype is exacerbated in the lung after LPS treatment as can be inferred from the accumulation of active immune cells in lung parenchyma. Overall, our results suggest that protective effects in cancer or inflammation shown by fibulin2 and ADAMTS12 as interactive partners in vitro are also shown in a more realistic in vivo context. Full article

Pleural mesothelioma (PM) is a type of cancer that is highly related to exposure to asbestos fibers. It shows aggressive behavior, and the current therapeutic approaches are usually insufficient to change the poor prognosis. Moreover, apart from staging and histological classification, there are no validated predictors of its response to treatment or its long-term outcomes. Numerous studies have investigated minimally invasive biomarkers in pleural fluid or blood to aid in earlier diagnosis and prognostic assessment of PM. The most studied marker in pleural effusion is mesothelin, which exhibits good specificity but low sensitivity, especially for non-epithelioid PM. Other biomarkers found in pleural fluid include fibulin-3, hyaluronan, microRNAs, and CYFRA-21.1, which have lower diagnostic capabilities but provide prognostic information and have potential roles as therapeutic targets. Serum is the most investigated matrix for biomarkers of PM. Several serum biomarkers in PM have been studied, with mesothelin, osteopontin, and fibulin-3 being the most often tested. A soluble mesothelin-related peptide (SMRP) is the only FDA-approved biomarker in patients with suspected mesothelioma. With different serum and pleural fluid cut-offs, it provides useful information on the diagnosis, prognosis, follow-up, and response to therapy in epithelioid PM. Panels combining different markers and proteomics technologies show promise in terms of improving clinical performance in the diagnosis and monitoring of mesothelioma patients. However, there is still no evidence that early detection can improve the treatment outcomes of PM patients. Full article

Matricellular proteins are secreted extracellular proteins that bear no primary structural functions but play crucial roles in tissue remodeling during development, homeostasis, and aging. Despite their low expression after birth, matricellular proteins within skin compartments support the structural function of many extracellular matrix proteins, such as collagens. In this review, we summarize the function of matricellular proteins in skin stem cell niches that influence stem cells’ fate and self-renewal ability. In the epidermal stem cell niche, fibulin 7 promotes epidermal stem cells’ heterogeneity and fitness into old age, and the transforming growth factor-β—induced protein ig-h3 (TGFBI)—enhances epidermal stem cell growth and wound healing. In the hair follicle stem cell niche, matricellular proteins such as periostin, tenascin C, SPARC, fibulin 1, CCN2, and R-Spondin 2 and 3 modulate stem cell activity during the hair cycle and may stabilize arrector pili muscle attachment to the hair follicle during piloerections (goosebumps). In skin wound healing, matricellular proteins are upregulated, and their functions have been examined in various gain-and-loss-of-function studies. However, much remains unknown concerning whether these proteins modulate skin stem cell behavior, plasticity, or cell–cell communications during wound healing and aging, leaving a new avenue for future studies. Full article

Our aim was to identify proteins that reflect an acute systemic response to prolonged hyperbaric stress and discover potential biomarker pathways for pulmonary O₂ toxicity. The study was a double-blind, randomized, crossover design in trained male Navy diver subjects. Each subject completed two dry resting hyperbaric chamber dives separated by a minimum of one week. One dive exposed the subject to 6.5 h of 100% oxygen (O₂) at 2ATA. The alternate dive exposed the subjects to an enhanced air nitrox mixture (EAN) containing 30.6% O₂ at the same depth for the same duration. Venous blood samples collected before (PRE) and after (POST) each dive were prepared and submitted to LC-MS/MS analysis (2 h runs). A total of 346 total proteins were detected and analyzed. A total of 12 proteins were significantly increased at EANPOST (vs. EANPRE), including proteins in hemostasis and immune signaling and activation. Significantly increased proteins at O₂PRE (vs. O₂POST) included neural cell adhesion molecule 1, glycoprotein Ib, catalase, hemoglobin subunit beta, fibulin-like proteins, and complement proteins. EANPOST and O₂POST differed in biomarkers related to coagulation, immune signaling and activation, and metabolism. Of particular interest is (EANPOST vs. O₂POST), which is protective against oxidative stress. Full article

Ten-eleven translocation (TET) enzymes catalyze the oxidation of 5-methylcytosine (5mC), first to 5-hydroxymethylcytosine (5hmC), then to 5-formylcytosine (5fC), and finally to 5-carboxycytosine (5caC). Evidence suggests that changes in TET expression may impact cell function and the phenotype of aging. Proliferation, apoptosis, markers of autophagy and double-strand DNA break repair, and the expression of Fibulin 5 were assessed by flow cytometry in TET1 and TET2-overexpressing fibroblasts isolated from sun-unexposed skin of young (23–35 years) and age-advanced (75–94 years) individuals. In cells derived from young individuals, TET1 overexpression resulted in the inhibition of proliferation and apoptosis by 37% (p = 0.03) and 24% (p = 0.05), respectively, while the overexpression of TET2 caused a decrease in proliferation by 46% (p = 0.01). Notably, in cells obtained from age-advanced individuals, TETs exhibited different effects. Specifically, TET1 inhibited proliferation and expression of autophagy marker Beclin 1 by 45% (p = 0.05) and 28% (p = 0.048), respectively, while increasing the level of γH2AX, a marker of double-strand DNA breaks necessary for initiating the repair process, by 19% (p = 0.04). TET2 inhibited proliferation by 64% (p = 0.053) and increased the level of γH2AX and Fibulin 5 by 46% (p = 0.007) and 29% (p = 0.04), respectively. These patterns of TET1 and TET2 effects suggest their involvement in regulating various fibroblast functions and that some of their biological actions depend on the donor’s age. Full article