Search Results (26)

The basement membrane (BM) is a specialized extracellular matrix that provides crucial structural support to tissues and organs. Mutations in BM genes can affect this structural support and are often associated with human diseases, including fibrosis, diabetes, and cancer, and are considered a hallmark of aging. However, how the BM maintains this support in organs with constant mechanical stress is largely unknown. In the Drosophila ovary, the BM provides the mechanical cues that are required for egg development. We discovered that the glycoprotein Ndg is important for maintaining organ integrity during egg production. Loss of Ndg results in a reduced number of progeny due to unfertilized eggs. Furthermore, we observed a decreased number of developing eggs and a premature death of egg chambers during development. Our results suggest that Ndg plays an important role in fertility. Full article

Rising global temperatures increase skin exposure to heat stress, which can impair skin structure and function. While several cosmetic ingredients have been developed to mitigate heat-induced damage, most primarily aim to enhance hydration or suppress inflammation, lacking mechanistic insights into their action under heat stress. This study assessed E. artemiae-derived SUPER-T and its exosome form, Thermasome, in heat-stressed human skin fibroblasts. Transcriptomic profiling revealed that heat stress upregulated heat-related thermal receptors and downregulated key extracellular matrix (ECM)-related genes. Notably, treatment with SUPER-T upregulated expression of these genes, suggesting a reparative role as a barrier to alleviate heat stress at the dermal–epidermal junction. For its application in a field of cosmetics, SUPER-T encapsulated in exosomes (Thermasome) enhanced the heat resilience, suggesting its better transdermal and heat protective effects. Thermasome further improved skin heat resilience and enhanced ECM gene expression including collagen genes. Our findings provide a mechanistic basis for the development of functional cosmetical materials that target ECM remodeling under heat-stressed conditions. Full article

Nidogen-2 (NID2) is a critical component of the extracellular matrix (ECM), which plays a regulatory role in cell adhesion, migration, differentiation, and survival. Previous studies have shown that NID2 is deregulated in several types of cancer, but its role in glioma is unknown. The present study investigated the prognostic value of NID2 in glioma and its associated molecular pathways and functional roles in malignant progression. The performed analyses included investigating the NID2 expression profile using the Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and tumor tissue microarray. The findings demonstrated that NID2 high expression predicts worse patient survival by both univariable and multivariable analyses. There is a strong correlation between NID2 upregulation and tumor grade. In stably NID2-overexpressed glioma cells, RNA-Seq analysis revealed coactivation of oncogenic functional pathways, including cell proliferation, survival, epithelial–mesenchymal transition, ECM organization, and migration. Overexpression of NID2 in U87MG and T98G cells promoted cell proliferation, migration, and invasion. TUNEL assay showed NID2 overexpression protected cells from apoptosis. Western blotting analysis showed activation of Akt and Bcl-xL in NID2-overexpressed cells. Our results show that NID2 is a promising prognostic marker in glioma. Full article

Despite advances in outcome, one third of children with acute myeloid leukemia (AML) relapse, and less than half will achieve long-term survival. Relapse in AML has been shown to be driven in part by leukemic stem cells (LSCs), highlighting the unmet medical need to better characterize and target this therapy-resistant cell population. Micro-array profiling of pediatric AML subpopulations (LSCs and leukemic myeloblasts) and their healthy counterparts revealed nidogen-1 (NID1) as expressed in both leukemic subpopulations while absent in the hematopoietic stem cell. Using the TARGET dataset including pediatric AML patients (n = 1025), NID1 expression showed a correlation with worse event-free survival and KMT2A rearrangements. Drug response profiling of a NID1 knockdown model demonstrated differential sensitivity to HSP90 inhibition. RNA sequencing and gene set enrichment analysis between NID1^high and NID1^low phenotypes showed involvement of NID1 in mitochondrial metabolic pathways known to be enriched in LSCs. Altogether, this study highlights NID1 as a novel oncogene associated with worse EFS and metabolic LSC phenotype in AML. NID1 could serve as a biomarker and aid in further mapping LSCs to establish therapeutic strategies tackling the high relapse rates in pediatric AML. Full article

Clinical and genetic studies strongly support a significant connection between nonalcoholic fatty liver disease (NAFLD) and atherosclerotic cardiovascular disease (ASCVD) and identify ASCVD as the primary cause of death in NAFLD patients. Understanding the molecular factors and mechanisms regulating these diseases is critical for developing novel therapies that target them simultaneously. Our preliminary immunoblotting experiments demonstrated elevated expression of nidogen 2 (NID2), a basement membrane glycoprotein, in human atherosclerotic vascular tissues and murine steatotic livers. Therefore, we investigated the role of NID2 in regulating hepatosteatosis and atherosclerosis utilizing Western diet-fed Apoe^−/− mice with/without NID2 overexpression. Quantitative real-time PCR confirmed increased NID2 mRNA expression in multiple organs (liver, heart, kidney, and adipose) of NID2-overexpressing mice. Male mice with NID2 overexpression exhibited higher liver and epididymal white adipose tissue mass, increased hepatic lipid accumulation, and fibrosis. Additionally, these mice developed larger atherosclerotic lesions in the whole aortas and aortic roots, with increased necrotic core formation. Mechanistic studies showed reduced AMPK activation in the livers of NID2-overexpressing mice compared with controls, without any effects on hepatic inflammation. In conclusion, these findings suggest that NID2 plays a deleterious role in both hepatosteatosis and atherosclerosis, making it a potential therapeutic target for these conditions. Full article

Viperid snake venoms are notably abundant in metalloproteinases (proteins) (SVMPs), which are primarily responsible for inducing hemorrhage and disrupting the hemostatic process and tissue integrity in envenomed victims. In this study, barnettlysin-III (Bar-III), a hemorrhagic P-III SVMP, was purified from the venom of the Peruvian snake Bothrops barnetti. Bar-III has a molecular mass of approximately 50 kDa and is a glycosylation-dependent functional metalloproteinase. Some biochemical properties of Bar-III, including the full amino acid sequence deduced from its cDNA, are reported. Its enzymatic activity is increased by Ca²⁺ ions and inhibited by an excess of Zn²⁺. Synthetic metalloproteinase inhibitors and EDTA also inhibit its proteolytic action. Bar-III degrades several plasma and ECM proteins, including fibrin(ogen), fibronectin, laminin, and nidogen. Platelets play a key role in hemostasis and thrombosis and in other biological process, such as inflammation and immunity, and platelet activation is driven by the platelet signaling receptors, glycoprotein (GP)Ib-IX-V, which binds vWF, and GPVI, which binds collagen. Moreover, Bar-III inhibits vWF- and convulxin-induced platelet aggregation in human washed platelets by cleaving the recombinant A1 domain of vWF and GPVI into a soluble ectodomain fraction of ~55 kDa (sGPVI). Bar-III does not reduce the viability of cultured endothelial cells; however, it interferes with the adhesion of these cells to fibronectin, vitronectin, and RGD peptides, as well as their migration profile. Bar-III binds specifically to the surface of these cells, and part of this interaction involves α5β1 integrin receptors. These results contribute to a better comprehension of the pathophysiology of snakebite accidents/incidents and could be used as a tool to explore novel and safer anti-venom therapeutics. Full article

The dermal–epidermal junction (DEJ) is essential for maintaining skin structural integrity and regulating cell survival and proliferation. Thus, DEJ rejuvenation is key for skin revitalization, particularly in age-related DEJ deterioration. Radiofrequency (RF) treatment, known for its ability to enhance collagen fiber production through thermal mechanisms and increase heat shock protein (HSP) expression, has emerged as a promising method for skin rejuvenation. Additionally, RF activates Piezo1, an ion channel implicated in macrophage polarization toward an M2 phenotype and enhanced TGF-β production. This study investigated the impact of RF treatment on HSP47 and HSP90 expression, known stimulators of DEJ protein expression. Furthermore, using in vitro and aged animal skin models, we assessed whether RF-induced Piezo1 activation and the subsequent M2 polarization could counter age-related DEJ changes. The RF treatment of H₂O₂-induced senescent keratinocytes upregulated the expression of HSP47, HSP90, TGF-β, and DEJ proteins, including collagen XVII. Similarly, the RF treatment of senescent macrophages increased Piezo1 and CD206 (M2 marker) expression. Conditioned media from RF-treated senescent macrophages enhanced the expression of TGF-β and DEJ proteins, such as nidogen and collagen IV, in senescent fibroblasts. In aged animal skin, RF treatment increased the expression of HSP47, HSP90, Piezo1, markers associated with M2 polarization, IL-10, and TGF-β. Additionally, RF treatment enhanced DEJ protein expression. Moreover, RF reduced lamina densa replication, disrupted lesions, promoted hemidesmosome formation, and increased epidermal thickness. Overall, RF treatment effectively enhanced DEJ protein expression and mitigated age-related DEJ structural changes by increasing HSP levels and activating Piezo1. Full article

Both nanostructure and multivalency enhance the biological activities of antimicrobial peptides (AMPs), whose mechanism of action is cooperative. In addition, the efficacy of a particular AMP should benefit from a steady concentration at the local place of action and, therefore, from a slow release after a dynamic repository. In the context of emerging multi-resistant bacterial infections and the urgent need for novel and effective antimicrobial drugs, we tested these concepts through the engineering of four AMPs into supramolecular complexes as pharmacological entities. For that purpose, GWH1, T22, Pt5, and PaD, produced as GFP or human nidogen-based His-tagged fusion proteins, were engineered as self-assembling oligomeric nanoparticles ranging from 10 to 70 nm and further packaged into nanoparticle-leaking submicron granules. Since these materials slowly release functional nanoparticles during their time-sustained unpacking, they are suitable for use as drug depots in vivo. In this context, a particular AMP version (GWH1-NIDO-H6) was selected for in vivo validation in a zebrafish model of a complex bacterial infection. The GWH1-NIDO-H6-secreting protein granules are protective in zebrafish against infection by the multi-resistant bacterium Stenotrophomonas maltophilia, proving the potential of innovative formulations based on nanostructured and slowly released recombinant AMPs in the fight against bacterial infections. Full article

We have previously shown that the extracellular matrix and basement membrane protein Nidogen1 (NID1) is secreted by more malignant, mesenchymal-like CRC cells and induces the epithelial–mesenchymal transition (EMT) and promotes the migration and invasion of less malignant, epithelial-like CRC cells. Here, we performed a comprehensive bioinformatics analysis of multiple datasets derived from CRC patients and showed that elevated expression of NID1 and the genes ITGA3, ITGB1, and ITGAV, which encode NID1 receptors, is associated with poor prognosis and advanced tumor stage. Accordingly, the expression of NID1, ITGA3, ITGB1, and ITGAV was associated with an EMT signature, which included SNAIL/SNAI1, an EMT-inducing transcription factor. In CRC cells, ectopic SNAIL expression induced NID1 and SNAIL occupancy was detected at an E-box upstream of the NID1 transcription start site. Therefore, NID1 represents a direct target of SNAIL. Ectopic expression of NID1 or treatment with NID1-containing medium endowed non-metastatic CRC cells with the capacity to form lung metastases after xenotransplantation into mice. Suppression of the NID1 receptor ITGAV decreased cell viability, particularly in CMS/consensus molecular subtype 4 CRC cells. Taken together, our results show that NID1 is a direct target of EMT-TF SNAIL and is associated with and promotes CRC progression and metastasis. Furthermore, the NID1 receptor ITGAV represents a candidate therapeutic target in CMS4 colorectal tumors. Full article

Endometrial and cervical cancers are the two most common gynaecological malignancies and among the leading causes of death worldwide. The extracellular matrix (ECM) is an important component of the cellular microenvironment and plays an important role in developing and regulating normal tissues and homeostasis. The pathological dynamics of the ECM contribute to several different processes such as endometriosis, infertility, cancer, and metastasis. Identifying changes in components of ECM is crucial for understanding the mechanisms of cancer development and its progression. We performed a systematic analysis of publications on the topic of changes in the extracellular matrix in cervical and endometrial cancer. The findings of this systematic review show that matrix metalloproteinases (MMP) play an important role impacting tumour growth in both types of cancer. MMPs degrade various specific substrates (collagen, elastin, fibronectin, aggrecan, fibulin, laminin, tenascin, vitronectin, versican, nidogen) and play a crucial role in the basal membrane degradation and ECM components. Similar types of MMPs were found to be increased in both cancers, namely, MMP-1, MMP-2, MMP-9, and MMP-11. Elevated concentrations of MMP-2 and MMP-9 were correlated with the FIGO stage and are associated with poor prognosis in endometrial cancer, whereas in cervical cancer, elevated concentrations of MMP-9 have been associated with a better outcome. Elevated ADAMTS levels were found in cervical cancer tissues. Elevated disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) levels were also found in endometrial cancer, but their role is still unclear. Following these findings, this review reports on tissue inhibitors of ECM enzymes, MMPs, and ADAMTS. The present review demonstrates changes in the extracellular matrix in cervical and endometrial cancers and compared their effect on cancer development, progression, and patient prognosis. Full article

Oxidative stress-induced cellular senescence and mitochondrial dysfunction result in skin aging by increasing ECM levels-degrading proteins such as MMPs, and decreasing collagen synthesis. MMPs also destroy the basement membrane, which is involved in skin elasticity. The extracellular matrix vitalizer RA^TM (RA) contains various antioxidants and sodium hyaluronate, which lead to skin rejuvenation. We evaluated whether RA decreases oxidative stress and mitochondrial dysfunction, eventually increasing skin elasticity in aged animals. Oxidative stress was assessed by assaying NADPH oxidase activity, which is involved in ROS generation, and the expression of SOD, which removes ROS. NADPH oxidase activity was increased in aged skin and decreased by RA injection. SOD expression was decreased in aged skin and increased by RA injection. Damage to mitochondrial DNA and mitochondrial fusion markers was increased in aged skin and decreased by RA. The levels of mitochondrial biogenesis markers and fission markers were decreased in aged skin and increased by RA. The levels of NF-κB/AP-1 and MMP1/2/3/9 were increased in aged skin and decreased by RA. The levels of TGF-β, CTGF, and collagen I/III were decreased in aged skin and increased by RA. The expression of laminin and nidogen and basement membrane density were decreased in aged skin and increased by RA. RA increased collagen fiber accumulation and elasticity in aged skin. In conclusion, RA improves skin rejuvenation by decreasing oxidative stress and mitochondrial dysfunction in aged skin. Full article

Wharton’s jelly stem cells (WJSC) from the human umbilical cord (UC) are one of the most promising mesenchymal stem cells (MSC) in tissue engineering (TE) and advanced therapies. The cell niche is a key element for both, MSC and fully differentiated tissues, to preserve their unique features. The basement membrane (BM) is an essential structure during embryonic development and in adult tissues. Epithelial BMs are well-known, but similar structures are present in other histological structures, such as in peripheral nerve fibers, myocytes or chondrocytes. Previous studies suggest the expression of some BM molecules within the Wharton’s Jelly (WJ) of UC, but the distribution pattern and full expression profile of these molecules have not been yet elucidated. In this sense, the aim of this histological study was to evaluate the expression of main BM molecules within the WJ, cultured WJSC and during WJSC microtissue (WJSC-MT) formation process. Results confirmed the presence of a pericellular matrix composed by the main BM molecules—collagens (IV, VII), HSPG2, agrin, laminin and nidogen—around the WJSC within UC. Additionally, ex vivo studies demonstrated the synthesis of these BM molecules, except agrin, especially during WJSC-MT formation process. The WJSC capability to synthesize main BM molecules could offer new alternatives for the generation of biomimetic-engineered substitutes where these molecules are particularly needed. Full article

Amyotrophic lateral sclerosis (ALS) is a complex disease characterized by the interplay of genetic and environmental factors for which, despite decades of intense research, diagnosis remains rather delayed, and most therapeutic options fail. Therefore, unravelling other potential pathogenetic mechanisms and searching for reliable markers are high priorities. In the present study, we employ the SOMAscan assay, an aptamer-based proteomic technology, to determine the circulating proteomic profile of ALS patients. The expression levels of ~1300 proteins were assessed in plasma, and 42 proteins with statistically significant differential expression between ALS patients and healthy controls were identified. Among these, four were upregulated proteins, Thymus- and activation-regulated chemokine, metalloproteinase inhibitor 3 and nidogen 1 and 2 were selected and validated by enzyme-linked immunosorbent assays in an overlapping cohort of patients. Following statistical analyses, different expression patterns of these proteins were observed in the familial and sporadic ALS patients. The proteins identified in this study might provide insight into ALS pathogenesis and represent potential candidates to develop novel targeted therapies. Full article

A wide range of viruses cause neurological manifestations in their hosts. Infection by neurotropic viruses as well as the resulting immune response can irreversibly disrupt the complex structural and functional architecture of the brain, depending in part on host genetic background. The interaction between host genetic background, neurological response to viral infection, and subsequent clinical manifestations remains poorly understood. In the present study, we used the genetically diverse Collaborative Cross (CC) mouse resource to better understand how differences in genetic background drive clinical signs and neuropathological manifestations of acute Theiler’s murine encephalomyelitis virus (TMEV) infection. For the first time, we characterized variations of TMEV viral tropism and load based on host genetic background, and correlated viral load with microglial/macrophage activation. For five CC strains (CC002, CC023, CC027, CC057, and CC078) infected with TMEV, we compared clinical signs, lesion distribution, microglial/macrophage response, expression, and distribution of TMEV mRNA, and identified genetic loci relevant to the early acute (4 days post-infection [dpi]) and late acute (14 dpi) timepoints. We examined brain pathology to determine possible causes of strain-specific differences in clinical signs, and found that fields CA1 and CA2 of the hippocampal formation were especially targeted by TMEV across all strains. Using Iba-1 immunolabeling, we identified and characterized strain- and timepoint-specific variation in microglial/macrophage reactivity in the hippocampal formation. Because viral clearance can influence disease outcome, we used RNA in situ hybridization to quantify viral load and TMEV mRNA distribution at both timepoints. TMEV mRNA expression was broadly distributed in the hippocampal formation at 4 dpi in all strains but varied between radiating and clustered distribution depending on the CC strain. We found a positive correlation between microglial/macrophage reactivity and TMEV mRNA expression at 4 dpi. At 14 dpi, we observed a dramatic reduction in TMEV mRNA expression, and localization to the medial portion of field CA1 and field CA2. To better understand how host genetic background can influence pathological outcomes, we identified quantitative trait loci associated with frequency of lesions in a particular brain region and with microglial/macrophage reactivity. These QTL were located near several loci of interest: lysosomal trafficking regulator (Lyst) and nidogen 1 (Nid1), and transmembrane protein 106 B (Tmem106b). Together, these results provide a novel understanding about the influences of genetic variation on the acute neuropathological and immunopathological environment and viral load, which collectively lead to variable disease outcomes. Our findings reveal possible avenues for future investigation which may lead to more effective intervention strategies and treatment regimens. Full article

Under the need for new functional and biocompatible materials for biomedical applications, protein engineering allows the design of assemblable polypeptides, which, as convenient building blocks of supramolecular complexes, can be produced in recombinant cells by simple and scalable methodologies. However, the stability of such materials is often overlooked or disregarded, becoming a potential bottleneck in the development and viability of novel products. In this context, we propose a design strategy based on in silico tools to detect instability areas in protein materials and to facilitate the decision making in the rational mutagenesis aimed to increase their stability and solubility. As a case study, we demonstrate the potential of this methodology to improve the stability of a humanized scaffold protein (a domain of the human nidogen), with the ability to oligomerize into regular nanoparticles usable to deliver payload drugs to tumor cells. Several nidogen mutants suggested by the method showed important and measurable improvements in their structural stability while retaining the functionalities and production yields of the original protein. Then, we propose the procedure developed here as a cost-effective routine tool in the design and optimization of multimeric protein materials prior to any experimental testing. Full article