Expression Of Adhesion Proteins Research Articles

NLRP3 activation maintains intestinal epithelial barrier and reduces liver injury in alcoholic liver disease mice.

Alcoholic liver disease (ALD) patients with bacterial infections usually exhibit high mortality rates. Infections frequently involve bacteria such as Vibrio vulnificus and Enterococcus faecalis. Nevertheless, the mechanisms predisposing ALD patients to bacterial infections and the role of the NLRP3 inflammasome in the intestinal epithelial barrier in ALD remain unclear. We established ALD mice models of WT, Nlrp3-/- and Gsdmd-/- through chronic alcohol consumption feeding and acute alcohol induction. We compared alterations in gut microbiota, ileitis, and adhesion protein expression, to analyze the role and potential mechanism of NLRP3 in the early onset of ALD. Concurrently, we examined the changes in inflammation and liver damage in the ileum of ALD and healthy mice following foodborne infection with V. vulnificus. Compared with the control group, the expression levels of ZO-1, Claudin-1 and E-cadherin were reduced in the ileum of ALD mice, while those of NLRP3, caspase-1(p20), GSDMD-N and IL-1β were elevated. Nlrp3-/- and Gsdmd-/- ALD mice showed an increased gut bacterial load, decreased ileal expression of E-cadherin, more severe ileitis, pronounced liver damage, steatosis and higher plasma levels of FITC-dextran, D-LA and ZO-1 compared with WT mice. Notably, Nlrp3-/- ALD mice exhibited a higher presence of Deferribacterota and Enterobacteriaceae. Furthermore, ALD mice infected with V. vulnificus infection exhibited no further activation of NLRP3 in the ileum, leading to increased intestinal permeability and bloodstream infections. This study indicated that NLRP3 activation in the ileum of ALD mice stabilizes the inflammation-related gut microbiota, preserves the intestinal epithelial barrier, and diminishes inflammation and liver injury. Furthermore, the compromised immune defence in ALD mice may contribute to their heightened susceptibility to bacterial pathogens. Activation of the NLRP3-GSDMD pathway in the ileum of Alcoholic liver disease (ALD) mice. NLRP3 activation maintains homeostasis of gut microbiota and intestinal epithelial barrier in ALD mice. ALD mice infected with V. vulnificus infection exhibited no further activation of NLRP3 in the ileum, leading to increased intestinal permeability and bloodstream infections.

Umbelliferone alleviates impaired wound healing and skin barrier dysfunction in high glucose-exposed dermal fibroblasts and diabetic skins

Skin wound healing is a complex process involving various cellular and molecular events. However, chronic wounds, particularly in individuals with diabetes, often experience delayed wound healing, potentially leading to diabetic skin complications. In this study, we examined the effects of umbelliferone on skin wound healing using dermal fibroblasts and skin tissues from a type 2 diabetic mouse model. Our results demonstrate that umbelliferone enhances several crucial aspects of wound healing. It increases the synthesis of key extracellular matrix components such as collagen I and fibronectin, as well as proteins involved in cell migration like EVL and Fascin-1. Additionally, umbelliferone boosts the secretion of angiogenesis factors VEGF and HIF-1α, enhances the expression of cell adhesion proteins including E-cadherin, ZO-1, and Occludin, and elevates levels of skin hydration-related proteins like HAS2 and AQP3. Notably, umbelliferone reduces the expression of HYAL, thereby potentially decreasing tissue permeability. As a result, it promotes extracellular matrix deposition, activates cell migration and proliferation, and stimulates pro-angiogenic factors while maintaining skin barrier functions. In summary, these findings underscore the therapeutic potential of umbelliferone in diabetic wound care, suggesting its promise as a treatment for diabetic skin complications.Key messagesUmbelliferone suppressed the breakdown of extracellular matrix components in the skin dermis while promoting their synthesis.Umbelliferone augmented the migratory and proliferative capacities of fibroblasts.Umbelliferone activated the release of angiogenic factors in diabetic wounds, leading to accelerated wound healing.Umbelliferone bolstered intercellular adhesion and reinforced the skin barrier by preventing moisture loss and preserving skin hydration.Graphical Summary of the protective impact of umbelliferone against delayed wound healing and skin barrier impairment in diabetic dermal fibroblasts and skin tissues.

Lactobacillus gasseri ATCC33323 affects the intestinal mucosal barrier to ameliorate DSS-induced colitis through the NR1I3-mediated regulation of E-cadherin.

Inflammatory bowel disease (IBD) is an immune system disorder primarily characterized by colitis, the exact etiology of which remains unclear. Traditional treatment approaches currently yield limited efficacy and are associated with significant side effects. Extensive research has indicated the potent therapeutic effects of probiotics, particularly Lactobacillus strains, in managing colitis. However, the mechanisms through which Lactobacillus strains ameliorate colitis require further exploration. In our study, we selected Lactobacillus gasseri ATCC33323 from the intestinal microbiota to elucidate the specific mechanisms involved in modulation of colitis. Experimental findings in a DSS-induced colitis mouse model revealed that L. gasseri ATCC33323 significantly improved physiological damage in colitic mice, reduced the severity of colonic inflammation, decreased the production of inflammatory factors, and preserved the integrity of the intestinal epithelial structure and function. It also maintained the expression and localization of adhesive proteins while improving intestinal barrier permeability and restoring dysbiosis in the gut microbiota. E-cadherin, a critical adhesive protein, plays a pivotal role in this protective mechanism. Knocking down E-cadherin expression within the mouse intestinal tract significantly attenuated the ability of L. gasseri ATCC33323 to regulate colitis, thus confirming its protective role through E-cadherin. Finally, transcriptional analysis and in vitro experiments revealed that L. gasseri ATCC33323 regulates CDH1 transcription by affecting NR1I3, thereby promoting E-cadherin expression. These findings contribute to a better understanding of the specific mechanisms by which Lactobacillus strains alleviate colitis, offering new insights for the potential use of L. gasseri as an alternative therapy for IBD, particularly in dietary supplementation.

Adhesion of retinal cells to gold surfaces by biomimetic molecules.

Neural cell-electrode coupling is crucial for effective neural and retinal prostheses. Enhancing this coupling can be achieved through surface modification and geometrical design to increase neuron-electrode proximity. In the current research, we focused on designing and studying various biomolecules as a method to elicit neural cell-electrode adhesion via cell-specific integrin mechanisms. We designed extracellular matrix biomimetic molecules with different head sequences (RGD or YIGSR), structures (linear or cyclic), and spacer lengths (short or long). These molecules, anchored by a thiol (SH) group, were deposited onto gold surfaces at various concentrations. We assessed the modifications using contact angle measurements, fluorescence imaging, and X-ray Photoelectron Spectroscopy (XPS). We then analyzed the adhesion of retinal cells and HEK293 cells to the modified surfaces by measuring cell density, surface area, and focal adhesion spots, and examined changes in adhesion-related gene and integrin expression. Results showed that YIGSR biomolecules significantly enhanced retinal cell adhesion, regardless of spacer length. For HEK293 cells, RGD biomolecules were more effective, especially with cyclic RGD and long spacers. Both cell types showed increased expression of specific adhesion integrins and proteins like vinculin and PTK2; these results were in agreement with the adhesion studies, confirming the cell-specific interactions with modified surfaces. This study highlights the importance of tailored biomolecules for improving neural cell adhesion to electrodes. By customizing biomolecules to foster specific and effective interactions with adhesion integrins, our study provides valuable insights for enhancing the integration and functionality of retinal prostheses and other neural implants.

Abstract We102: Synthetic N-Acylurea Derivative Reduces Angiogenesis in Human Endothelial Cells by Talin Modulation

Talin is a focal adhesion protein that activates integrins and recruits other focal adhesion proteins. Talin regulates the interactions between integrins and the extracellular matrix, which are critical for endothelial cells during angiogenesis. In this study, we successfully synthesized a novel talin modulator, N-((2-(1H-indol-3-yl)ethyl)carbamoyl)-2-(benzo[d][1,3]dioxol-5-yloxy)acetamide, referred to as KCH-1521. KCH-1521 was determined to bind talin and modulate downstream signaling molecules of talin. After 24 hrs of treatment, KCH-1521 changed the cell morphology of HUVECs and reduced focal adhesion protein expression including vinculin and paxillin. Talin downstream signaling is regulated via FAK, AKT, and ERK pathways, however, treatment with KCH-1521 decreased phosphorylation of FAK, AKT, and ERK, leading to a reduction of cell proliferation, survival, and angiogenesis. Interestingly, the expression of various angiogenic genes was significantly decreased after treatment with KCH-1521. Also, in vitro tube forming assay revealed that KCH-1521 reduced angiogenic networks in a time-dependent manner. To investigate the reversibility of its effects, KCH-1521 was removed after treatment. HUVECs recovered their morphology through rearrangement of the cytoskeleton and the expression of angiogenic genes was also recovered. By further optimization and in vivo studies of KCH-1521, a novel drug of talin modulation could be used to achieve therapeutic anti-angiogenesis for vascular diseases and cancers.

Loss of primary cilia and dopaminergic neuroprotection in pathogenic LRRK2-driven and idiopathic Parkinson’s disease

Activating leucine-rich repeat kinase 2 (LRRK2) mutations cause Parkinson's and phosphorylation of Rab10 by pathogenic LRRK2 blocks primary ciliogenesis in cultured cells. In the mouse brain, LRRK2 blockade of primary cilia is highly cell type specific: For example, cholinergic interneurons and astrocytes but not medium spiny neurons of the dorsal striatum lose primary cilia in LRRK2-pathway mutant mice. We show here that the cell type specificity of LRRK2-mediated cilia loss is also seen in human postmortem striatum from patients with LRRK2 pathway mutations and idiopathic Parkinson's. Single nucleus RNA sequencing shows that cilia loss in mouse cholinergic interneurons is accompanied by decreased glial-derived neurotrophic factor transcription, decreasing neuroprotection for dopamine neurons. Nevertheless, LRRK2 expression differences cannot explain the unique vulnerability of cholinergic neurons to LRRK2 kinase as much higher LRRK2 expression is seen in medium spiny neurons that have normal cilia. In parallel with decreased striatal dopaminergic neurite density, LRRK2 G2019S neurons show increased autism-linked CNTN5 adhesion protein expression; glial cells show significant loss of ferritin heavy chain. These data strongly suggest that loss of cilia in specific striatal cell types decreases neuroprotection for dopamine neurons in mice and human Parkinson's.

Absence of Aquaporin-4 (AQP4) Prolongs the Presence of a CD11c+ Microglial Population during Postnatal Corpus Callosum Development.

Aquaporin-4 (AQP4) expression is associated with the development of congenital hydrocephalus due to its structural role in the ependymal membrane. Gene expression analysis of periaqueductal tissue in AQP4-knockout (KO) mice at 11 days of age (P11) showed a modification in ependymal cell adhesion and ciliary protein expression that could alter cerebrospinal fluid homeostasis. A microglial subpopulation of CD11c+ cells was overexpressed in the periaqueductal tissue of mice that did not develop hydrocephalus, suggesting a possible protective effect. Here, we verified the location of this CD11c+ expression in the corpus callosum (CC) and cerebellum of AQP4-KO mice and analysed its time course. Immunofluorescence labelling of the CD11c protein in the CC and cerebellum of WT and KO animals at P3, P5, P7 and P11 confirmed an expanded presence of these cells in both tissues of the KO animal; CD11c+ cells appeared at P3 and reached a peak at P11, whereas in the WT animal, they appeared at P5, reached their peak at P7 and were undetectable by P11. The gene expression analysis in the CC samples at P11 confirmed the presence of CD11c+ microglial cells in this tissue. Among the more than 4000 overexpressed genes, Spp1 stood out with the highest differential gene expression (≅600), with other genes, such as Gpnmb, Itgax, Cd68 and Atp6v0d2, also identified as overexpressed. Therefore, CD11c+ cells appear to be necessary for normal corpus callosum development during postnatal life, and the absence of AQP4 prolonged its expression in this tissue.

Interplay of hypoxia and host cells in the translocation, invasion and dissemination of Taenia solium in neurocysticercosis

Neurocysticercosis, caused by the invasion of the central nervous system (CNS) by Taenia solium larvae, poses a significant global health burden. Despite its prevalence and severe neurological consequences, understanding of the molecular and signalling pathways facilitating parasite dissemination and CNS invasion is limited. The lack of comprehensive knowledge of host-parasite interactions and associated proteins involved in T. solium infection hinders the development of targeted interventions to mitigate its ability to cross the epithelia barrier. This is complicated by reduced oxygen availability in the intestine, a phenomenon called hypoxia. Hypoxia can result in epithelial barrier disruption and cell damage, thereby promoting the translocation and dissemination of T. solium. This study aims to establish the role of hypoxia in T. solium invasion and disseminated infections. The effect of hypoxia on the migration, viability and morphological characteristics of T. solium would be determined using transwell invasion assays, flow cytometry and microscopy. T. solium oncosphere development and dissemination under hypoxic and normoxic conditions will be monitored using animal models. Also, host-parasite transcriptome and proteome profiling will be performed to determine pathways triggered under hypoxic conditions. It is expected that hypoxia would promote the invasion and dissemination of T. solium by enhancing epithelial and endothelial cell permeability. , hypoxia will induce the expression of binding and adhesion proteins and other virulence markers such as enolase, serpin, and glutathione transferases that are involved in host invasion. Understanding the role of hypoxia in the translocation mechanism of T. solium can be leveraged to provide insights into host tissues dissemination and the development of appropriate interventions.

Functional profiling of resident cells during vascular aging

Introduction: Depending on surrounding cell types, substrate mechanics, and chemical agonists, vascular cell types – including endothelial (ECs) and smooth muscle cells (VSMC) — modulate their behavior to maintain homeostasis. Aging perturbs this homeostasis resulting in EC and SMC dysfunction, marked by impaired barrier integrity and pathological ECM remodeling. Endothelial-to-mesenchymal transition (EndMT) in ECs and “dedifferentiation” of VSMCs towards a synthetic phenotype are phenomenon under investigation as cellular drivers of the widespread dysregulation seen with aging. The overall goal of this project is to understand the effect of cross-talk between ECM and growth factor signaling on vascular cell plasticity during aging. Materials and Methods: Human aortic endothelial cells (HAECs) were seeded onto transwell inserts after seven days treatment with or without TGF-β. After growing to confluence on the insert, cells were subjected to a FITC-dextran transwell assay. A parallel group of cells was seeded onto fibronectin coated glass-bottom dishes and stained for the expression of focal adhesion proteins and cell-type markers. Mouse aortic smooth muscle cells (maSMCs) were isolated from C57Bl6 mice at 3 (young), 6 (early middle-aged; EMA), 9 (middle-age; MA), or greater than 18 months of age (old). Cells were seeded onto dye-quenched (DQ) collagen type I (Col-I) substrate before gain of fluorescence was measured in proximity to the cell as well as in the surrounding media. A parallel group of cells were allowed to grow in media containing FITC Col-I, and gain of fluorescence was measured in proximity to the cells. Each cell type (3M, 6M, 9M, and 18M) in both experiments (DQ and FITC) were further treated with MMP inhibitor, TG2 inhibitor and TGF-β1 to measure their impacts on Col-I turnover. Results: Barrier function was not impaired in ECs cultured with TGF-β1, relative to their untreated counterparts. Mouse aortic SMCs isolated from older mice had decreased rates of Col-I cleavage and were more susceptible to MMP inhibition than their younger counterparts. Conclusions: maSMCs from older mice have lower Col-I turnover than their younger counterparts. This is consistent with bulk tissue behavior, as it is well known that relative collagen levels increase in the elastic vasculature as we age. TGF-β1 treatment did not have an effect on permeability of 4kd FITC-dextran, it is feasible that there will be an impact on the larger 70kd fragments. Travis Brady is supported by the NASEM Ford Foundation Pre-doctoral Fellowship. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Vitamin A Status Modulates Epithelial Mesenchymal Transition in the Lung: The Role of Furin.

Vitamin A deficiency (VAD) induced TGF-β hyperactivation and reduced expression of cell adhesion proteins in the lung, suggesting that the disruption of retinoic acid (RA) signaling leads to epithelial-mesenchymal transition (EMT). To elucidate the role of lung vitamin A status in EMT, several EMT markers and the expression of the proprotein convertase furin, which activates TGF-β, were analyzed in two experimental models. Our in vivo model included control rats, VAD rats, and both control rats and VAD rats, treated with RA. For the in vitro studies, human bronchoalveolar epithelial cells treated with RA were used. Our data show that EMT and furin are induced in VAD rats. Furthermore, furin expression continues to increase much more markedly after treatment of VAD rats with RA. In control rats and cell lines, an acute RA treatment induced a significant increase in furin expression, concomitant with changes in EMT markers. A ChIP assay demonstrated that RA directly regulates furin transcription. These results emphasize the importance of maintaining vitamin A levels within the physiological range since both levels below and above this range can cause adverse effects that, paradoxically, could be similar. The role of furin in EMT is discussed.

Effects of syndecan-4 silencing on the extracellular matrix remodeling in anoikis-resistant endothelial cells.

Anoikis is a process of programmed cell death induced by the loss of cell/matrix interactions. In previous work, we have shown that the acquisition of anoikis resistance upregulates syndecan-4 (SDC4) expression in endothelial cells. In addition, SDC4 gene silencing by microRNA interference reverses the transformed phenotype of anoikis-resistant endothelial cells. Due to this role of SDC4 in regulating the behavior of anoikis-resistant endothelial cells, we have evaluated that the functional consequences of SDC4 silencing in the extracellular matrix (ECM) remodeling in anoikis-resistant rabbit aortic endothelial cells submitted to SDC4 gene silencing (miR-Syn4-Adh-1-EC). For this, we evaluated the expression of adhesive proteins, ECM receptors, nonreceptor protein-tyrosine kinases, and ECM-degrading enzymes and their inhibitors. Altered cell behavior was monitored by adhesion, migration, and tube formation assays. We found that SDC4 silencing led to a decrease in migration and angiogenic capacity of anoikis-resistant endothelial cells; this was accompanied by an increase in adhesion to fibronectin. Furthermore, after SDC4 silencing, we observed an increase in the expression of fibronectin, collagen IV, and vitronectin, and a decrease in the expression of integrin α5β1 and αvβ3, besides that, silenced cells show an increase in Src and FAK expression. Quantitative polymerase chain reactionand Western blot analysis demonstrated that SDC4 silencing leads to altered gene and protein expression of MMP2, MMP9, and HSPE. Compared withparental cells, SDC4 silenced cells showed a decrease in nitric oxide production and eNOS expression. In conclusion, these data demonstrate that SDC4 plays an important role in ECM remodeling. In addition, our findings represent an important step towardunderstanding the mechanism by which SDC4 can reverse the transformed phenotype of anoikis-resistant endothelial cells.

The suppression of cell motility through the reduction of FAK activity and expression of cell adhesion proteins by hAMSCs secretome in MDA-MB-231 breast cancer cells.

Breast cancer is a leading cause of death in women worldwide. Cancer therapy based on stem cells is considered as a novel and promising platform. In the present study, we explore the therapeutic effects of human amniotic mesenchymal stromal cells (hAMSCs) through the reduction of focal adhesion kinase (FAK) activity, SHP-2, and cell adhesion proteins such as Paxillin, Vinculin, Fibronectin, Talin, and integrin αvβ3 expression in MDA-MB-231 breast cancer cells. For this purpose, we employed a co-culture system using 6-well plate transwell. After 72h, hAMSCs-treated MDA-MB-231 breast cancer cells, the activity of focal adhesion kinase (FAK) and the expression of SHP-2 and cell adhesion proteins such as Paxillin, Vinculin, Fibronectin, Talin, and integrin αvβ3 expression were analyzed using western blot. The shape and migration of cells were also analyzed. Based on our results, a significant reduction in tumor cell motility through downregulation of the tyrosine phosphorylation level of FAK (at Y397 and Y576/577 sites) and cell adhesion expression in MDA-MB-231 breast cancer cells was demonstrated. Our findings indicate that hAMSCS secretome has therapeutic effects on cancer cell migration through downregulation of FAK activity and expression of cell adhesion proteins.

Surface-Engineered Titanium with Nanoceria to Enhance Soft Tissue Integration Via Reactive Oxygen Species Modulation and Nanotopographical Sensing.

The design of implantable biomaterials involves precise tuning of surface features because the early cellular fate on such engineered surfaces is highly influenced by many physicochemical factors [roughness, hydrophilicity, reactive oxygen species (ROS) responsiveness, etc.]. Herein, to enhance soft tissue integration for successful implantation, Ti substrates decorated with uniform layers of nanoceria (Ce), called Ti@Ce, were optimally developed by a simple and cost-effective in situ immersion coating technique. The characterization of Ti@Ce shows a uniform Ce distribution with enhanced roughness (∼3-fold increase) and hydrophilicity (∼4-fold increase) and adopted ROS-scavenging capacity by nanoceria coating. When human gingival fibroblasts were seeded on Ti@Ce under oxidative stress conditions, Ti@Ce supported cellular adhesion, spreading, and survivability by its cellular ROS-scavenging capacity. Mechanistically, the unique nanocoating resulted in higher expression of amphiphysin (a nanotopology sensor), paxillin (a focal adhesion protein), and cell adhesive proteins (collagen-1 and fibronectin). Ti@Ce also led to global chromatin condensation by decreasing histone 3 acetylation as an early differentiation feature. Transcriptome analysis by RNA sequencing confirmed the chromatin remodeling, antiapoptosis, antioxidant, cell adhesion, and TGF-β signaling-related gene signatures in Ti@Ce. As key fibroblast transcription (co)factors, Ti@Ce promotes serum response factor and MRTF-α nucleus localization. Considering all of this, it is proposed that the surface engineering approach using Ce could improve the biological properties of Ti implants, supporting their functioning at soft tissue interfaces and utilization as a bioactive implant for clinical conditions such as peri-implantitis.

Pip5k1c expression in osteocytes regulates bone remodeling in mice

Research backgroundThe role of osteocytes in maintaining bone mass has been progressively emphasized. Pip5k1c is the most critical isoform among PIP5KIs, which can regulate cytoskeleton, biomembrane, and Ca2+ release of cells and participate in many processes, such as cell adhesion, differentiation, and apoptosis. However, its expression and function in osteocytes are still unclear. Materials and methodsTo determine the function of Pip5k1c in osteocytes, the expression of Pip5k1c in osteocytes was deleted by breeding the 10-kb mouse Dmp1-Cre transgenic mice with the Pip5k1cfl/fl mice. Bone histomorphometry, micro-computerized tomography analysis, immunofluorescence staining and western blotting were used to determine the effects of Pip5k1c loss on bone mass. In vitro, we explored the mechanism by siRNA knockdown of Pip5k1c in MLO-Y4 cells. ResultsPip5k1c expression was decreased in osteocytes in senescent and osteoporotic tissues both in humans and mice. Loss of Pip5k1c in osteocytes led to a low bone mass in long bones and spines and impaired biomechanical properties in femur, without changes in calvariae. The loss of Pip5k1c resulted in the reduction of the protein level of type 1 collagen in tibiae and MLO-Y4 cells. Osteocyte Pip5k1c loss reduced the osteoblast and bone formation rate with high expression of sclerostin, impacting the osteoclast activities at the same time. Moreover, Pip5k1c loss in osteocytes reduced expression of focal adhesion proteins and promoted apoptosis. ConclusionOur studies demonstrate the critical role and mechanism of Pip5k1c in osteocytes in regulating bone remodeling. The translational potential of this articleOsteocyte has been considered to a key role in regulating bone homeostasis. The present study has demonstrated that the significance of Pip5k1c in bone homeostasis by regulating the expression of collagen, sclerostin and focal adhesion expression, which provided a possible therapeutic target against human metabolic bone disease.

The evaluation of DNA aptamer monolayers on silicon surface for the promotion of cell-surface interaction

DNA aptamers are very specific towards biological targets and are useful in many biosensor applications. However, there had been little reports that systematically examined the potential of DNA aptamers as surface thin film for promoting cell-surface adhesion. In this work, three aptamers (IDA, NC3S and SYL3C) were grafted on silicon surface and were only selective towards epithelial cell type. To better demonstrate this selectivity, click chemistry on underlying PEG layer was performed to attach these DNA aptamers on the surfaces so as to discourage non-specific cell attachment. The physicochemical properties of the surfaces were examined via XPS, AFM, FTIR and contact angle goniometry. A range of different cell types (MDA-MB 231, A549, MES-SA, N2A and HaCaT) were incubated to these surfaces and their viability, morphology and focal adhesion protein expression levels were quantified after a period of 24 h. From our observations, we had shown that NC3S and SYL3C can actively promote cell adhesion while integrin targeting IDA did not help to improve the outcomes of cell-surface interaction. Moreover, aptamer functionalized surfaces were observed to be only favorably towards epithelial cell types and our current findings here had help shed light on DNA aptamer as potential bioactive thin films that are cell type selective.

Copine C plays a role in adhesion and streaming in Dictyostelium

ABSTRACT Copines are a family of calcium-dependent membrane-binding proteins. To study these proteins, anull mutant for cpnC was created in Dictyostelium, which has six copines genes (cpnA-cpnF). During development, cpnC− cells were able to aggregate, but did not form streams. Once aggregated into mounds, they formed large ring structures. cpnC− cells were less adherent to plastic substrates, but more adherent to other cells. These phenotypes correlated with changes in adhesion protein expression with decreased expression of SibA and increased expression of CsaA in developing cpnC− cells. We also measured the expression of RegA, a cAMP phosphodiesterase, and found that cpnC− cells have reduced RegA expression. The reduced RegA expression in cpnC− cells is most likely responsible for the observed phenotypes.

Lung lymphatic endothelial cells undergo inflammatory and prothrombotic changes in a model of chronic obstructive pulmonary disease.

The lymphatic vasculature regulates lung homeostasis through drainage of fluid and trafficking of immune cells and plays a key role in the response to lung injury in several disease states. We have previously shown that lymphatic dysfunction occurs early in the pathogenesis of chronic obstructive pulmonary disease (COPD) caused by cigarette smoke (CS) and that this is associated with increased thrombin and fibrin clots in lung lymph. However, the direct effects of CS and thrombin on lymphatic endothelial cells (LECs) in COPD are not entirely clear. Studies of the blood vasculature have shown that COPD is associated with increased thrombin after CS exposure that causes endothelial dysfunction characterized by changes in the expression of coagulation factors and leukocyte adhesion proteins. Here, we determined whether similar changes occur in LECs. We used an in vitro cell culture system and treated human lung microvascular lymphatic endothelial cells with cigarette smoke extract (CSE) and/or thrombin. We found that CSE treatment led to decreased fibrinolytic activity in LECs, which was associated with increased expression of plasminogen activator inhibitor 1 (PAI-1). LECs treated with both CSE and thrombin together had a decreased expression of tissue factor pathway inhibitor (TFPI) and increased expression of adhesion molecules. RNA sequencing of lung LECs isolated from mice exposed to CS also showed upregulation of prothrombotic and inflammatory pathways at both acute and chronic exposure time points. Analysis of publicly available single-cell RNA sequencing of LECs as well as immunohistochemical staining of lung tissue from COPD patients supported these data and showed increased expression of inflammatory markers in LECs from COPD patients compared to those from controls. These studies suggest that in parallel with blood vessels, the lymphatic endothelium undergoes inflammatory changes associated with CS exposure and increased thrombin in COPD. Further research is needed to unravel the mechanisms by which these changes affect lymphatic function and drive tissue injury in COPD.

Biological Properties of 3D-Printed Zirconia Implants with p-Cell Structures

Research on 3-dimensional (3D) printed porous zirconia-based dental implants is still in its infancy. This study aimed to evaluate the biological responses of novel zirconia implants with p-cell structures fabricated by 3D printing. The solid zirconia samples exhibited comparable density, 3-point flexural strength, and accelerated aging properties compared to specimens prepared previously by conventional methods. Cell-based experiments showed that the p-cell structure promoted cell proliferation, adhesion, and osteogenesis-related protein expression. Mechanical tests showed that both p-cell and control implants could withstand a torque of 35 Ncm without breaking. The mean maximum breaking loads of p-cell and control implants were 1,222.429 ± 115.591 N and 1,903.857 ± 250.673 N, respectively, which were much higher than the human physiological chewing force and human mean maximum occlusal force. An animal experiment showed that the bone trabeculae around the implants were significantly thicker, more numerous, and denser in the p-cell group than in the control group. This work could provide promising guidance for further exploring 3D printing techniques for porous zirconia bionic implants in dentistry.

Red Blood Cell Contribution to Thrombosis in Polycythemia Vera and Essential Thrombocythemia.

Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms (MPN) characterized by clonal erythrocytosis and thrombocytosis, respectively. The main goal of therapy in PV and ET is to prevent thrombohemorrhagic complications. Despite a debated notion that red blood cells (RBCs) play a passive and minor role in thrombosis, there has been increasing evidence over the past decades that RBCs may play a biological and clinical role in PV and ET pathophysiology. This review summarizes the main mechanisms that suggest the involvement of PV and ET RBCs in thrombosis, including quantitative and qualitative RBC abnormalities reported in these pathologies. Among these abnormalities, we discuss increased RBC counts and hematocrit, that modulate blood rheology by increasing viscosity, as well as qualitative changes, such as deformability, aggregation, expression of adhesion proteins and phosphatidylserine and release of extracellular microvesicles. While the direct relationship between a high red cell count and thrombosis is well-known, the intrinsic defects of RBCs from PV and ET patients are new contributors that need to be investigated in depth in order to elucidate their role and pave the way for new therapeutical strategies.

Synergistic Effect of Nano Strontium Titanate Coating and Ultraviolet C Photofunctionalization on Osteogenic Performance and Soft Tissue Sealing of poly(ether-ether-ketone).

This study aimed to evaluate the bioactivity of poly(ether ether ketone) (PEEK) after surface modification by persistent photoconductive strontium titanate (SrTiO3) magnetron sputtering and ultraviolet (UV) C irradiation. According to the different modifications, the PEEK specimens were randomly divided into five groups (n = 38/group): PEEK, Sr100-PEEK, Sr200-PEEK, UV/PEEK, and UV/Sr200-PEEK. Then, the specimens of Sr100-PEEK and Sr200-PEEK groups were, respectively, coated with 100 and 200 nm thickness photocatalyst SrTiO3 on the PEEK surface by magnetron sputtering. Subsequently, UV-C light photofunctionalized the specimens of PEEK and Sr200-PEEK groups to form UV/PEEK and UV/Sr200-PEEK groups. The specimens were characterized by a step meter, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDX), and a water contact angle meter. The release test of the Sr ion was performed by inductively coupled plasma mass spectrometry (ICP-MS). In vitro study, osteogenic activity (MC3T3-E1 osteoblast-like cells) and epithelial and connective tissue attachment (gingival epithelial cells GE1 and fibroblasts NIH3T3) were analyzed in five groups. Surface morphology of the specimens was changed after coating, and the Sr content on the Sr-PEEK surface was increased with increasing coating thickness. In addition, the contact angle was increased significantly after magnetron sputtering. After UV-C photofunctionalization, the content of surface elements changed and the contact angle was decreased. The release of Sr ion was sustained, and the final cumulative release amount did not exceed the safety limit. In vitro experiments showed that SrTiO3 improved the cell activity of MC3T3-E1 and UV-C irradiation further enhanced the osteogenic performance of PEEK. Besides, UV-C irradiation also significantly promoted the cell viability, development, and expression of adhesion proteins of GE1 and NIH3T3 on PEEK. The present investigation demonstrated that nano SrTiO3 coating with UV-C photofunctionalization synergistically enhanced the osteogenic properties and soft tissue sealing function of PEEK in vitro.