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989 result(s) for "Collagen secretion"
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Biallelic TANGO1 mutations cause a novel syndromal disease due to hampered cellular collagen secretion
The transport and Golgi organization 1 (TANGO1) proteins play pivotal roles in the secretory pathway. Full length TANGO1 is a transmembrane protein localised at endoplasmic reticulum (ER) exit sites, where it binds bulky cargo within the ER lumen and recruits membranes from the ER Golgi intermediate compartment to create an exit route for their export. Here we report the first TANGO1-associated syndrome in humans. A synonymous substitution that results in exon eight skipping in most mRNA molecules, ultimately leading to a truncated TANGO1 protein was identified as disease-causing mutation. The four homozygously affected sons of a consanguineous family display severe dentinogenesis imperfecta, short stature, various skeletal abnormalities, insulin-dependent diabetes mellitus, sensorineural hearing loss, and mild intellectual disability. Functional studies in HeLa and U2OS cells revealed that the corresponding truncated TANGO1 protein is dispersed in the ER and its expression in cells with intact endogenous TANGO1 impairs cellular collagen I secretion.
Stimulation of type II collagen biosynthesis and secretion in bovine chondrocytes cultured with degraded collagen
The functional integrity of articular cartilage is dependent on the maintenance of the extracellular matrix (ECM), a process which is controlled by chondrocytes. The regulation of ECM biosynthesis is complex and a variety of substances have been found to influence chondrocyte metabolism. In the present study we have investigated the effect of degraded collagen on the formation of type II collagen by mature bovine chondrocytes in a cell culture model. The culture medium was supplemented with collagen hydrolysate (CH) and biosynthesis of type II collagen by chondrocytes was compared to control cells treated with native type I and type II collagen and a collagen-free protein hydrolysate. The quantification of type II collagen by means of an ELISA technique was confirmed by immunocytochemical detection as well as by the incorporation of (14)C-proline in the ECM after a 48 h incubation. Chondrocytes in the control group were maintained in the basal medium for 11 days. The presence of extracellular CH led to a dose-dependent increase in type II collagen secretion. However, native collagens as well as a collagen-free hydrolysate of wheat proteins failed to stimulate the production of type II collagen in chondrocytes. These results clearly indicate a stimulatory effect of degraded collagen on the type II collagen biosynthesis of chondrocytes and suggest a possible feedback mechanism for the regulation of collagen turnover in cartilage tissue.
SOX9 Promotes Collagen VI Secretion by Upregulating PCOLCE in Neurofibroma
Neurofibromatosis type 1 (NF1) is caused by NF1 gene mutations. Patients with NF1 often have complications with tumors, such as neurofibroma. In order to investigate the pathogenesis of human neurofibroma, a systematic comparison of protein expression levels between Schwann cell-like sNF96.2 cells, which originated from malignant peripheral nerve sheath tumors (MPNST), and normal Schwann cells was performed using 4-D label-free proteomic analysis. In addition, the expression levels and localization of dysregulated proteins were confirmed using a Gene Expression Omnibus (GEO) transcriptomic dataset, Western blot analysis, and immunofluorescence labeling. The effects of SRY-box transcription factor 9 (SOX9) in the neurofibroma and surrounding microenvironment were evaluated in vivo using a tumor transplantation model. The present study observed that SOX9 and procollagen C-endopeptidase enhancer (PCOLCE) were significantly altered. NF1 mutation promoted the nuclear translocation and transcriptional activity of SOX9 in neurofibromas. SOX9 increased collagen VI secretions by enhancing the activation of PCOLCE in neurofibroma cells. These findings might provide new perspectives on the pathophysiological significance of SOX9 in neurofibromas and elucidate a novel molecular mechanism underlying neurofibromas.
An injectable hyaluronic acid/lithium calcium silicate soft tissue filler with vascularization and collagen regeneration
The significance of collagen and vascular in skin augmentation have been recognized in recent years. However, current skin tissue fillers, e.g. hyaluronic acid (HA) or HA-based hydrogel, fail to meet the perfect augmentation requirements due to their inadequate long-term support effect and the lack of tissue-inducing activity. Herein, an injectable skin filler containing hyaluronic acid (HA) hydrogel and lithium calcium silicate (LCS, Li2Ca4Si4O13) bioceramic microspheres was developed for skin tissue fillers, owing to the excellent biological function of silicate bioceramics. The HA-LCS fillers could be easily injected through a tiny standard medical needle (27 G) with force of less than 36 N, and showed good biocompatibility both in vitro and in vivo. Furthermore, the bioactive ions released from HA-LCS fillers significantly enhanced the expression of vascularization-related genes and collagen-related genes. Importantly, the HA-LCS fillers not only stimulated the regeneration of mature blood vessels, but also promoted collagen secretion in dermal skin and filling area. This study not only presented an injectable filler with enhanced regeneration of blood vessels and collagen, but also provided a new strategy for developing tissue-induced fillers based on bioactive components of silicate bioceramics. [Display omitted] •LCS bioceramic microspheres were synthesized via a sol-spray strategy.•HA-LCS fillers were prepared by encapsulating LCS microspheres in HA hydrogels.•HA-LCS fillers exhibited perfect injectability and biocompatibility.•HA-LCS fillers promoted vascularization and collagen secretion in vitro and in vivo.•HA-LCS fillers were considered as a promising filler in promoting skin augmentation.
Effect of microtextured titanium sheets using laser enhances proliferation and collagen synthesis of mouse fibroblasts via the TGF-β/Smad pathway
Purpose This study investigates the effects of hexagonal microtextured titanium sheets on fibroblast growth and collagen synthesis, crucial factors in anastomotic healing. Materials and methods Hexagonal titanium sheets were fabricated using a laser microtextured machine. Mouse fibroblastic embryonic stem cells (NIH/3T3) were cultured on these sheets. Cell proliferation was assessed using a CCK8 assay, and expression of TGF-β/Smad pathway-related genes and collagen types I and III was evaluated through qRT-PCR and western blot. Results Hexagonal titanium sheets significantly enhanced fibroblast growth and collagen synthesis. The 50–30 group, with the smallest contact angle (48 ± 2.3°), exhibited the highest cell growth rates by CCK8 assay. Gene expression analysis revealed that TGF-β1, Smad2, Smad3, Smad4, and COL1A1 were significantly upregulated in the 50–30 group on day 7. Meanwhile, type I collagen expression was significantly increased in the 50–30 group on day 7 by western blot analysis. Conclusion Our findings demonstrate that laser-fabricated hexagonal microtextured titanium sheets enhance hydrophilicity and promote fibroblast growth, activating the TGF-β/Smad pathway to facilitate collagen synthesis. These results have important implications for tissue repair and regeneration.
Loss of TANGO1 Leads to Absence of Bone Mineralization
TANGO1 (transport and Golgi organization‐1 homolog) encodes a transmembrane protein, which is located at endoplasmic reticulum (ER) exit sites where it binds bulky cargo, such as collagens, in the lumen and recruits membranes from the ER‐Golgi intermediate compartment (ERGIC) to create an export route for cargo secretion. Mice lacking Mia3 (murine TANGO1 orthologue) show defective secretion of numerous procollagens and lead to neonatal lethality due to insufficient bone mineralization. Recently, aberrant expression of truncated TANGO1 in humans has been shown to cause a mild‐to‐moderate severe collagenopathy associated with dentinogenesis imperfecta, short stature, skeletal abnormalities, diabetes mellitus, and mild intellectual disability. We now show for the first time that complete loss of TANGO1 results in human embryonic lethality with near‐total bone loss and phenocopies the situation of Mia3−/− mice. Whole‐exome sequencing on genomic DNA (gDNA) of an aborted fetus of Indian descent revealed a homozygous 4‐base pair (4‐bp) deletion in TANGO1 that is heterozygously present in both healthy parents. Parental fibroblast studies showed decreased TANGO1 mRNA expression and protein levels. Type I collagen secretion and extracellular matrix organization were normal, supporting a threshold model for clinical phenotype development. As such, our report broadens the phenotypic and mutational spectrum of TANGO1‐related collagenopathies, and underscores the crucial role of TANGO1 for normal bone development, of which deficiency results in a severe‐to‐lethal form of osteochondrodysplasia. © 2021 American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
Mechanical force regulates the paracrine functions of ADSCs to assist skin expansion in rats
Background In the repair of massive tissue defects using expanded large skin flaps, the incidence of complications increases with the size of the expanded area. Currently, stem cell therapy has limitations to solve this problem. We hypothesized that conditioned medium of adipose-derived stem cells (ADSC-CM) collected following mechanical pretreatment can assist skin expansion. Methods Rat aortic endothelial cells and fibroblasts were cultured with ADSC-CM collected under 0%, 10%, 12%, and 15% stretching force. Ten-milliliter cylindrical soft tissue expanders were subcutaneously implanted into the backs of 36 Sprague-Dawley rats. The 0% and 10% stretch groups were injected with ADSC-CM collected under 0% and 10% stretching force, respectively, while the control group was not injected. After 3, 7, 14, and 30 days of expansion, expanded skin tissue was harvested for staining and qPCR analyses. Results Endothelial cells had the best lumen formation and highest migration rate, and fibroblasts secreted the most collagen upon culture with ADSC-CM collected under 10% stretching force. The skin expansion rate was significantly increased in the 10% stretch group. After 7 days of expansion, the number of blood vessels in the expanded area, expression of the angiogenesis-associated proteins vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor, and collagen deposition were significantly increased in the 10% stretch group. Conclusions The optimal mechanical force upregulates specific paracrine proteins in ADSCs to increase angiogenesis and collagen secretion, and thereby promote skin regeneration and expansion. This study provides a new auxiliary method to expand large skin flaps.
Effect of Commonly Used Cosmetic Preservatives on Healthy Human Skin Cells
Cosmetic products contain preservatives to prevent microbial growth. The various types of preservatives present in skincare products applied on the skin induce many side effects. We tested several types of preservatives such as phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea (IU), the composition of gluconolactone and sodium benzoate (GSB), diazolidinyl urea (DU), and two grapefruit essential oils, one of which was industrially produced and a second which was freshly distilled from fresh grapefruit peels. This study aimed to find the relationship between preservative concentration, cell growth, collagen secretion, and cell viability. We hypothesized that these products induced a decrease in collagen secretion from human dermal fibroblasts. Our research, for the first time, addressed the overall effect of other preservatives on skin extracellular matrix (ECM) by studying their effect on metalloproteinase-2 (MMP-2) activity. Except for cytotoxicity and contact sensitivity tests, there are no studies of their effect on skin ECM in the available literature. These studies show potential antimicrobial activity, especially from the compounds IU and DU towards reference bacteria and the compounds methyl paraben and propyl paraben against reference fungi. The MTS test showed that fibroblasts are more sensitive to the tested group of preservatives than keratinocytes, which could be caused by the differences between the cells’ structures. The grapefruit oils exhibited the most cytotoxicity to both tested cell lines compared to all considered preservatives. The most destructive influence of preservatives on collagen synthesis was observed in the case of IU and DU. In this case, the homemade grapefruit oil turned out to be the mildest one. The results from a diverse group of preservatives show that whether they are natural or synthesized compounds, they require controlled use. Appropriate dosages and evaluation of preservative efficacy should not be the only aspects considered. The complex effect of preservatives on skin processes and cytotoxicity is an important topic for modern people.
The metal transporter ZIP13 supplies iron into the secretory pathway in Drosophila melanogaster
The intracellular iron transfer process is not well understood, and the identity of the iron transporter responsible for iron delivery to the secretory compartments remains elusive. In this study, we show Drosophila ZIP13 (Slc39a13), a presumed zinc importer, fulfills the iron effluxing role. Interfering with dZIP13 expression causes iron-rescuable iron absorption defect, simultaneous iron increase in the cytosol and decrease in the secretory compartments, failure of ferritin iron loading, and abnormal collagen secretion. dZIP13 expression in E. coli confers upon the host iron-dependent growth and iron resistance. Importantly, time-coursed transport assays using an iron isotope indicated a potent iron exporting activity of dZIP13. The identification of dZIP13 as an iron transporter suggests that the spondylocheiro dysplastic form of Ehlers–Danlos syndrome, in which hZIP13 is defective, is likely due to a failure of iron delivery to the secretory compartments. Our results also broaden our knowledge of the scope of defects from iron dyshomeostasis. Iron is essential for life. Amongst its many important roles, iron is crucial for producing collagen—the protein that provides both strength and elasticity to bones, tendons, ligaments, and skin. Like many other proteins, collagens are produced inside the endoplasmic reticulum—an organelle inside the cell that is enclosed by a membrane that is similar to the plasma membrane that surrounds the cell itself. Two enzymes that are critical for producing collagen need to bind with iron in order to work correctly. To do this, iron in the cytoplasm of the cell has to cross the membrane that surrounds the endoplasmic reticulum. Small molecules are commonly transported across membranes by proteins called transporters, which tend to work on specific types of ions or molecules. However, researchers did not know the identity of the membrane transporter responsible for moving iron into the secretory pathway—including the endoplasmic reticulum—to bind with the enzymes that produce collagen. Xiao, Wan et al. have now investigated the function of the transporter ZIP13 in the fruit fly Drosophila. This transporter was thought to transport zinc across membranes and into the cytoplasm. Instead, Xiao, Wan et al. found that ZIP13 transports iron out of the cytoplasm and into the endoplasmic reticulum. Ehlers–Danlos syndrome is a condition that causes individuals to suffer from frequent joint dislocations, bone deformities, and fragile skin as a result of their body producing collagen incorrectly. One form of Ehlers–Danlos syndrome is caused by ZIP13 transporters working incorrectly. However, this was difficult to understand when it was thought that ZIP13 only transports zinc. The discovery that ZIP13 mostly transports iron rather than zinc can explain the link between this transporter and Ehlers–Danlos syndrome: if ZIP13 doesn't work, the collagen-building enzymes cannot get the iron they need to work properly. Disorders caused by iron deficiencies are normally identified by a few tell-tale symptoms, such as anemia, but these are not seen in Ehlers–Danlos syndrome. Xiao, Wan et al. suggest that iron transport problems could therefore be behind a wider range of diseases and disorders than is currently known.
The Effect of Activated FXIII, a Transglutaminase, on Vascular Smooth Muscle Cells
Plasma factor XIII (pFXIII) is a heterotetramer of FXIII-A and FXIII-B subunits. The cellular form (cFXIII), a dimer of FXIII-A, is present in a number of cell types. Activated FXIII (FXIIIa), a transglutaminase, plays an important role in clot stabilization, wound healing, angiogenesis and maintenance of pregnancy. It has a direct effect on vascular endothelial cells and fibroblasts, which have been implicated in the development of atherosclerotic plaques. Our aim was to explore the effect of FXIIIa on human aortic smooth muscle cells (HAoSMCs), another major cell type in the atherosclerotic plaque. Osteoblastic transformation induced by Pi and Ca2+ failed to elicit the expression of cFXIII in HAoSMCs. EZ4U, CCK-8 and CytoSelect Wound Healing assays were used to investigate cell proliferation and migration. The Sircol Collagen Assay Kit was used to monitor collagen secretion. Thrombospondin-1 (TSP-1) levels were measured by ELISA. Cell-associated TSP-1 was detected by the immunofluorescence technique. The TSP-1 mRNA level was estimated by RT-qPCR. Activated recombinant cFXIII (rFXIIIa) increased cell proliferation and collagen secretion. In parallel, a 67% decrease in TSP-1 concentration in the medium and a 2.5-fold increase in cells were observed. TSP-1 mRNA did not change significantly. These effects of FXIIIa might contribute to the pathogenesis of atherosclerotic plaques.