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Von Willebrand Factor (VWF) can promote platelet adhesion to the post-atherosclerotic regions to initiate thrombosis. The synthesis and secretion of VWF are important functions of endothelial cells (ECs). However, the mechanism through which blood flow regulates endothelial secretion of VWF remains unclear. We utilized a parallel-plate flow apparatus to apply fluid shear stress to human umbilical vein endothelial cells (HUVECs). Compared with pulsatile shear stress that mimics laminar flow in the straight parts of arteries or upstream of atherosclerotic stenosis sites, short-term exposure to oscillatory shear stress (OS) that mimics disturbed flow increased VWF secretion independent of affecting synaptosomal-associated protein 23 (SNAP23) expression and promoted the translocation of SNAP23 to the cell membrane. Vimentin associated with SNAP23, and this association was enhanced by OS or histamine. Acrylamide, a reagent that disrupts vimentin intermediate filaments, prevented histamine/OS-induced SNAP23 translocation, as well as VWF secretion. Immunofluorescence analysis revealed that the polarity of the vimentin intermediate filament network decreased after stimulation with histamine or OS. In addition, inhibition of protein kinase A (PKA) or G protein coupled receptor 68 (GPR68) eliminated the histamine/OS-induced phosphorylation of vimentin at Ser38 and secretion of VWF. Furthermore, syntaxin 7 might assist with the translocation of SNAP23 to the cell membrane, thus playing a role in promoting VWF secretion. The GPR68/PKA/vimentin signaling pathway may represent a novel mechanism for the regulation of SNAP23-mediated VWF secretion by ECs under OS and provide strategies for the prevention of atherosclerosis-related thrombosis.

Introduction: As a comprehensive sport, Marathon presents high demands concerning the athletes’ comprehensive capacity. Objective: This paper explores to what extent balance skill training can effectively contribute to improving physical fitness for marathon runners. Methods: 120 marathon runners were selected for the pilot experiment. The experimental group received balance training, while the control group underwent no intervention. Results: In the experimental group, the time with eyes closed and feet apart increased from 33.559 ± 15.8570 to 37.203 ± 15.5865s, the time spent in the T-shaped run from 10.144 ± 0.5063s to 9.908 ± 0.5225s, the time spent in the standing long jump from 2.831 ± 0.2648m to 3.058 ± 0.3183m, and the time spent in the T-shaped run from 55.544 ± 2.2581 to 60.845 ± 2.4367 times/min. The total FMS score changed from 14.618 ± 0.9392 to 18.481 ± 1.3909. Shoulder flexibility increased from 2.777 ± 0.4756 to 2.917 ± 0.2994, and active straight knee raise changed from 2.306 ± 0.4692 to 2.803 ± 0.403. Conclusion: Daily balance training can be added to usual marathon training to improve the fitness of its athletes. Level of evidence II; Therapeutic studies - investigation of treatment outcomes. RESUMO Introdução: A maratona, enquanto esporte integral, apresenta altas exigências relativas à capacidade plena dos atletas. Objetivo: Este artigo tenta explorar em que medida o treinamento da habilidade de equilíbrio pode efetivamente contribuir para o aprimoramento da aptidão física aos praticantes do esporte de corrida de maratona. Métodos: 120 corredores de maratona foram selecionados para o experimento piloto. O grupo experimental recebeu treinamento de equilíbrio, enquanto o grupo de controle não sofreu qualquer intervenção. Resultados: No grupo experimental, o tempo com olhos fechados e pés separados aumentou de 33,559 ± 15,8570 para 37,203 ± 15,5865s, o tempo gasto na corrida em forma de T de 10,144 ± 0,5063s para 9,908 ± 0,5225s, o tempo gasto no salto em pé em distância de 2,831 ± 0,2648m para 3,058 ± 0,3183m, e o tempo gasto na corrida em forma de T de 55,544 ± 2,2581 para 60,845 ± 2,4367 vezes/min. A pontuação total de FMS mudou de 14,618 ± 0,9392 para 18,481 ± 1,3909. A flexibilidade do ombro aumentou de 2,777 ± 0,4756 para 2,917 ± 0,2994, e o levantamento reto do joelho ativo mudou de 2,306 ± 0,4692 para 2,803 ± 0,403. Conclusão: O treinamento de equilíbrio diário pode ser adicionado ao treino de maratona habitual para melhorar a aptidão física de seus atletas. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento. RESUMEN Introducción: El maratón, como deporte integral, presenta grandes exigencias en cuanto a la capacidad integral de los atletas. Objetivo: Este trabajo pretende explorar hasta qué punto el entrenamiento de las habilidades de equilibrio puede contribuir eficazmente a la mejora de la condición física de los corredores de maratón. Métodos: Se seleccionaron 120 corredores de maratón para el experimento piloto. El grupo experimental recibió entrenamiento de equilibrio, mientras que el grupo de control no se sometió a ninguna intervención. Resultados: En el grupo experimental, el tiempo con los ojos cerrados y los pies separados aumentó de 33,559 ± 15,8570 a 37,203 ± 15,5865s, el tiempo empleado en la carrera en forma de T de 10,144 ± 0,5063s a 9,908 ± 0,5225s, el tiempo empleado en el salto de longitud de pie de 2,831 ± 0,2648m a 3,058 ± 0,3183m, y el tiempo empleado en la carrera en forma de T de 55,544 ± 2,2581 a 60,845 ± 2,4367 veces/min. La puntuación total de FMS pasó de 14,618 ± 0,9392 a 18,481 ± 1,3909. La flexibilidad de los hombros aumentó de 2,777 ± 0,4756 a 2,917 ± 0,2994, y la elevación activa de la rodilla pasó de 2,306 ± 0,4692 a 2,803 ± 0,403. Conclusión: El entrenamiento diario del equilibrio puede añadirse al entrenamiento habitual de maratón para mejorar la forma física de sus atletas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Disturbed blood flow induces endothelial pro-inflammatory responses that promote atherogenesis. Nanoparticle-based therapeutics aimed at treating endothelial inflammation in vasculature where disturbed flow occurs may provide a promising avenue to prevent atherosclerosis. By using a vertical-step flow apparatus and a microfluidic chip of vascular stenosis, herein, it is found that the disk-shaped versus the spherical nanoparticles exhibit preferential margination (localization and adhesion) to the regions with the pro-atherogenic disturbed flow. By employing a mouse model of carotid partial ligation, superior targeting and higher accumulation of the disk-shaped particles are also demonstrated within disturbed flow areas than that of the spherical particles. In hyperlipidemia mice, administration of disk-shaped particles loaded with hypomethylating agent decitabine (DAC) displays greater anti-inflammatory and anti-atherosclerotic effects compared with that of the spherical counterparts and exhibits reduced toxicity than "naked" DAC. The findings suggest that shaping nanoparticles to disk is an effective strategy for promoting their delivery to atheroprone endothelia.

Vascular smooth muscle cell (SMC) from arterial stenotic-occlusive diseases is featured with deficiency in mitochondrial respiration and loss of cell contractility. However, the regulatory mechanism of mitochondrial genes and mitochondrial energy metabolism in SMC remains elusive. Here, we described that DNA methyltransferase 1 (DNMT1) translocated to the mitochondria and catalyzed D-loop methylation of mitochondrial DNA in vascular SMCs in response to platelet-derived growth factor-BB (PDGF-BB). Mitochondrial-specific expression of DNMT1 repressed mitochondrial gene expression, caused functional damage, and reduced SMC contractility. Hypermethylation of mitochondrial D-loop regions were detected in the intima-media layer of mouse carotid arteries subjected to either cessation of blood flow or mechanical endothelial injury, and also in vessel specimens from patients with carotid occlusive diseases. Likewise, the ligated mouse arteries exhibited an enhanced mitochondrial binding of DNMT1, repressed mitochondrial gene expression, defects in mitochondrial respiration, and impaired contractility. The impaired contractility of a ligated vessel could be restored by ex vivo transplantation of DNMT1-deleted mitochondria. In summary, we discovered the function of DNMT1-mediated mitochondrial D-loop methylation in the regulation of mitochondrial gene transcription. Methylation of mitochondrial D-loop in vascular SMCs contributes to impaired mitochondrial function and loss of contractile phenotype in vascular occlusive disease.

Vascular endothelial cells are exposed to shear stresses with disturbed vs. laminar flow patterns, which lead to proinflammatory vs. antiinflammatory phenotypes, respectively. Effective treatment against endothelial inflammation and the consequent atherogenesis requires the identification of new therapeutic molecules and the development of drugs targeting these molecules. Using Connectivity Map, we have identified vitexin, a natural flavonoid, as a compound that evokes the gene-expression changes caused by pulsatile shear, which mimics laminar flow with a clear direction, vs. oscillatory shear (OS), which mimics disturbed flow without a clear direction. Treatment with vitexin suppressed the endothelial inflammation induced by OS or tumor necrosis factor-α. Administration of vitexin to mice subjected to carotid partial ligation blocked the disturbed flow-induced endothelial inflammation and neointimal formation. In hyperlipidemic mice, treatment with vitexin ameliorated atherosclerosis. Using SuperPred, we predicted that apurinic/apyrimidinic endonuclease1 (APEX1) may directly interact with vitexin, and we experimentally verified their physical interactions. OS induced APEX1 nuclear translocation, which was inhibited by vitexin. OS promoted the binding of acetyltransferase p300 to APEX1, leading to its acetylation and nuclear translocation. Functionally, knocking down APEX1 with siRNA reversed the OS-induced proinflammatory phenotype, suggesting that APEX1 promotes inflammation by orchestrating the NF-κB pathway. Animal experiments with the partial ligation model indicated that overexpression of APEX1 negated the action of vitexin against endothelial inflammation, and that endothelial-specific deletion of APEX1 ameliorated atherogenesis. We thus propose targeting APEX1 with vitexin as a potential therapeutic strategy to alleviate atherosclerosis.

Vascular smooth muscle cell (vSMC) is highly plastic as its phenotype can change in response to mechanical cues inherent to the extracellular matrix (ECM). VSMC may be activated from its quiescent contractile phenotype to a proinflammatory phenotype, whereby the cell secretes chemotactic and inflammatory cytokines, e.g. MCP1 and IL6, to functionally regulate monocyte and macrophage infiltration during the development of various vascular diseases including arteriosclerosis. Here, by culturing vSMCs on polyacrylamide (PA) substrates with variable elastic moduli, we discovered a role of discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase that binds collagens, in mediating the mechanical regulation of vSMC gene expression, phenotype, and proinflammatory responses. We found that ECM stiffness induced DDR1 phosphorylation, oligomerization, and endocytosis to repress the expression of DNA methyltransferase 1 (DNMT1), very likely in a collagen-independent manner. The DDR1-to-DNMT1 signaling was sequentially mediated by the extracellular signal-regulated kinases (ERKs) and p53 pathways. ECM stiffness primed vSMC to a proinflammatory phenotype and this regulation was diminished by DDR1 inhibition. In agreement with the in vitro findings, increased DDR1 phosphorylation was observed in human arterial stiffening. DDR1 inhibition in mouse attenuated the acute injury or adenine diet-induced vascular stiffening and inflammation. Furthermore, mouse vasculature with SMC-specific deletion of Dnmt1 exhibited proinflammatory and stiffening phenotypes. Our study demonstrates a role of SMC DDR1 in perceiving the mechanical microenvironments and down-regulating expression of DNMT1 to result in vascular pathologies and has potential implications for optimization of engineering artificial vascular grafts and vascular networks.

Vascular smooth muscle cells (SMCs) can adapt to changes in cellular geometric cues; however, the underlying mechanisms remain elusive. Using 2D micropatterned substrates to engineer cell geometry, it is found that in comparison with an elongated geometry, a square-shaped geometry causes the nuclear-to-cytoplasmic redistribution of DNA methyltransferase 1 (DNMT1), hypermethylation of mitochondrial DNA (mtDNA), repression of mtDNA gene transcription, and impairment of mitochondrial function. Using irregularly arranged versus circumferentially aligned vascular grafts to control cell geometry in 3D growth, it is demonstrated that cell geometry, mtDNA methylation, and vessel contractility are closely related. DNMT1 redistribution is found to be dependent on the phosphoinositide 3-kinase and protein kinase B (AKT) signaling pathways. Cell elongation activates cytosolic phospholipase A2, a nuclear mechanosensor that, when inhibited, hinders AKT phosphorylation, DNMT1 nuclear accumulation, and energy production. The findings of this study provide insights into the effects of cell geometry on SMC function and its potential implications in the optimization of vascular grafts.

Macrophage-mediated inflammatory responses occur throughout all stages of atherosclerosis. DNA methylation is one of the critical epigenetic mechanisms and is associated with the development of atherosclerosis. The underlying mechanism of epigenetic regulation of macrophage inflammation (M1 activation) remains unclear. Here we aim to study the role of DNA methyltransferase 1 (DNMT1) in modulating macrophage inflammation and atherosclerosis. DNMT1 expression is up-regulated in THP-1-derived macrophages upon treatment with lipopolysaccharide (LPS) and interferon-gamma (IFN-γ). Overexpression of DNMT1 promotes the LPS- and IFN-γ-induced M1 activation whereas inhibition of DNMT1 attenuates it. Consistently, DNMT1 expression is elevated in macrophages in atherosclerotic plaques from human and mouse specimens; compared with the Dnmt1wild-type, myeloid Dnmt1 deficiency in mice in an Apolipoprotein E (ApoE) knockout background or receiving AAV-PSCK9 injection and carotid partial ligation results in ameliorated atheroma formation and suppressed plaque inflammation. The promoter regions of atheroprotective Krüppel-like factor 4 (KLF4) are hypermethylated in M1- activated macrophages. DNMT1 down-regulates the expression of KLF4, probably through catalyzing DNA methylation of the promoter regions of KLF4. Gain- and loss-of function study of KLF4 indicates that the DNMT1-mediated macrophage M1 activation is dependent on KLF4. Our data demonstrate a proatherogenic role for DNMT1 as a defining factor in macrophage inflammation both in vitro and in vivo. DNMT1 promotes macrophage M1 activation by suppressing KLF4 expression. Thus macrophage-specific DNMT1 inhibition may provide an attractive therapeutic potential to prevent or reduce atherosclerosis.

Background: Hyperuricemia causes gout syndrome, which can manifest as hemorheological damage. However, hemorheological properties have not been well characterized in asymptomatic conditions. Aims: The present study was aimed to investigate the hemorheological changes in rats with asymptomatic hyperuricemia. Methods and Materials: The rat model was established by intraperitoneal injection of 250 mg/(kg·d) oxonate acid for 8 weeks. In one group of rats, 70 mg/(kg·d) allopurinol was also administrated for the latter 4 weeks. Control rats were administered CMCNa solution and water. Results: Hyperuricemic rats had higher blood viscosity than control rats did. Moreover, their erythrocytes had reduced deformation index, orientation index, surface charges, and osmotic fragility. Treatment with allopurinol decreased the blood uric acid amounts and improved the hemorheological parameters. Conclusions: Our study suggests that there is deterioration in the hemorheology of hyperuricemic rats and that allopurinol can play a protective role on the deterioration. Therefore, hemorheology can be used as a diagnostic tool in asymptomatic hyperuricemia.

Chinese dragon’s blood, the red resin ofDracaena cochinchinensis, one of the renowned traditional medicines, has been used to facilitate blood circulation and disperse blood stasis for thousands of years. Phenolic compounds are considered to be responsible for its main biological activities. In this study, total phenolic compounds of Chinese dragon’s blood were made into capsule (Longxuetongluo Capsule, LTC) and their effects on the abnormal hemorheological properties were examined by high fat diet (HFD) induced ApoE−/− mice. Compared to the model group, LTC recovered the abnormal hemorheological parameters in HFD-induced ApoE−/− mice by reducing whole blood viscosity (WBV) at high rate and improving erythrocyte function. In conclusion, LTC could ameliorate erythrocyte deformability and osmotic fragility through the reduction of lipid peroxidation on plasma and erythrocyte membranes in HFD-induced ApoE−/− mice, which supported the traditional uses of Chinese dragon’s blood as an effective agent for improving blood microcirculation in hypercholesterolemia.

(1) Background: There are no successive treatments for heart failure with preserved ejection fraction (HFpEF) because of complex interactions between environmental, histological, and genetic risk factors. The objective of the study is to investigate changes in cardiomyocytes and molecular networks associated with HFpEF. (2) Methods: Dahl salt-sensitive (DSS) rats developed HFpEF when fed with a high-salt (HS) diet for 7 weeks, which was confirmed by in vivo and ex vivo measurements. Shotgun proteomics, microarray, Western blot, and quantitative RT-PCR analyses were further carried out to investigate cellular and molecular mechanisms. (3) Results: Rats with HFpEF showed diastolic dysfunction, impaired systolic function, and prolonged repolarization of myocytes, owing to an increase in cell size and apoptosis of myocytes. Heatmap of multi-omics further showed significant differences between rats with HFpEF and controls. Gene Set Enrichment Analysis (GSEA) of multi-omics revealed genetic risk factors involved in cardiac muscle contraction, proteasome, B cell receptor signaling, and p53 signaling pathway. Gene Ontology (GO) analysis of multi-omics showed the inflammatory response and mitochondrial fission as top biological processes that may deteriorate myocyte stiffening. GO analysis of protein-to-protein network indicated cytoskeleton protein, cell fraction, enzyme binding, and ATP binding as the top enriched molecular functions. Western blot validated upregulated Mff and Itga9 and downregulated Map1lc3a in the HS group, which likely contributed to accumulation of aberrant mitochondria to increase ROS and elevation of myocyte stiffness, and subsequent contractile dysfunction and myocardial apoptosis. (4) Conclusions: Multi-omics analysis revealed multiple pathways associated with HFpEF. This study shows insight into molecular mechanisms for the development of HFpEF and may provide potential targets for the treatment of HFpEF.

The earliest atherosclerotic lesions preferentially develop in arterial regions experienced disturbed blood flow, which induces endothelial expression of pro-atherogenic genes and the subsequent endothelial dysfunction. Our previous study has demonstrated an up-regulation of DNA methyltransferase 1 (DNMT1) and a global hypermethylation in vascular endothelium subjected to disturbed flow. Here, we determined that DNMT1-specific inhibition in arterial wall ameliorates the disturbed flow-induced atherosclerosis through, at least in part, targeting cell cycle regulator cyclin A and connective tissue growth factor (CTGF). We identified the signaling pathways mediating the flow-induction of DNMT1. Inhibition of the mammalian target of rapamycin (mTOR) suppressed the DNMT1 up-regulation both in vitro and in vivo. Together, our results demonstrate that disturbed flow influences endothelial function and induces atherosclerosis in an mTOR/DNMT1-dependent manner. The conclusions obtained from this study might facilitate further evaluation of the epigenetic regulation of endothelial function during the pathological development of atherosclerosis and offer novel prevention and therapeutic targets of this disease.

The distal tubule and collecting duct in kidney regulate water homeostasis. TMOD1 is an actin capping protein that plays an important role in controlling the organization of actin filaments. In this study, we found TMOD1 was specifically expressed in distal tubules and collecting ducts. To investigate the role of TMOD1, we created Tmod1flox/flox mice and bred them with Ksp-Cre mice to generate tubule-specific Tmod1 knockout mice, Tmod1flox/flox/Ksp-Cre+ (designated as TFK). As compared with control mice, TFK mice showed oliguria, hyperosmolality urine, and high blood pressure. To determine the mechanisms underlying this phenotype, we performed label-free quantitative proteomics on kidneys of TFK and control mice. Total of 83 proteins were found differentially expressed. Bioinformatic analysis indicated that biological processes, including protein phosphorylation and metabolic process, were involved in TMOD1 regulatory network. Gene set enrichment analysis showed that multiple pathways, such as phosphatidylinositol signaling system and GnRH signaling pathway, were strongly associated with Tmod1 knockout. Western blot validated the down-regulation of three proteins, TGFBR2, SLC25A11, and MTFP1, in kidneys of TFK mice. Our study provides valuable information on the molecular functions and the regulatory network of Tmod1 gene in kidney, as well as the new mechanisms for the regulation of water balance.

Objective Urea transporter-B (UT-B), highly expressed in erythrocyte, confers specific permeability to urea, urea analogues and water. The purpose of this study was to determine the hemorheological properties of UT-B null erythrocyte using a series of biophysical techniques. Methods and results The blood was taken from UT-B knockout and wild-type mice and the hemorheological parameters were measured. The UT-B inhibitor, PU-14, was used to treat the erythrocyte of wild-type mice in vitro and the deformability of the treated erythrocyte was analyzed. The results showed that UT-B knockout improves the hemorheological properties of erythrocyte, including increased erythrocyte deformation index, small deformation index, orientation index, low osmotic fragility and high electrophoretic rate. The UT-B inhibitor PU-14 had the similar effect as UT-B knockout on the deformation indices. The whole blood viscosity in UT-B knockout mice showed reduction trend as compared to wild-type mice. Conclusions The data indicate that UT-B is involved in the regulation of hemorheology, which suggests that UT-B may be a potential therapeutic target for improving the hemorheology in some metabolic and hereditary diseases.

Dendritic cells (DCs), the most potent antigen-presenting cells, play a central role in the initiation, regulation, and maintenance of the immune responses. Vascular endothelial growth factor (VEGF) is one of the important cytokines in the tumor microenvironment (TME) and can inhibit the differentiation and functional maturation of DCs. To elucidate the potential mechanisms of DC dysfunction induced by VEGF, the effects of VEGF on the biophysical characteristics and motility of human mature DCs (mDCs) were investigated. The results showed that VEGF had a negative influence on the biophysical properties, including electrophoretic mobility, osmotic fragility, viscoelasticity, and transmigration. Further cytoskeleton structure analysis by confocal microscope and gene expression profile analyses by gene microarray and real-time PCR indicated that the abnormal remodeling of F-actin cytoskeleton may be the main reason for the deterioration of biophysical properties, motility, and stimulatory capability of VEGF-treated mDCs. This is significant for understanding the biological behavior of DCs and the immune escape mechanism of tumors. Simultaneously, the therapeutic efficacies may be improved by blocking the signaling pathway of VEGF in an appropriate manner before the deployment of DC-based vaccinations against tumors.

Hematopoietic stem cells (HSCs) are tissue specific stem cells that replenish all mature blood lineages during the lifetime of an individual. Hematopoietic cell clusters in the aorta of vertebrate embryos play a pivotal role in the formation of the adult blood system. Recently, people have learned a lot about the embryonic HSCs on their development and homing. During their differentiation, HSCs are regulated by the transcription factors, such as Runx1 and Notch signaling pathway, etc. MicroRNAs also regulate the self-renewal and differentiation of hematopoietic stem/progenitor cells on the post-transcriptional levels. Since the onset of circulation, the formation of HSCs and their differentiation into blood cells, especially red blood cells, are regulated by the hemodynamic forces. It would be of great significance if we could treat hematologic diseases with induced HSCs in vitro on the basis of fully understanding of hemotopoietic stem cell development. This review is focused on the advances in the research of HSCs' development and regulation.

Hyperuricemia is a risk factor for various diseases, but knowledge on acute hyperuricemia is still not sufficient. The present study was aimed to investigate the effect of acute hyperuricemia on red blood cells from hemorheological point of view, and to provide the reference for clinical treatment. The rats were gavaged with 500 mg/kg hypoxanthine and intraperitoneally injected with 100 mg/kg oxonate to induce the model of acute hyperuricemia. The same volume of blood samples were drawn within time period of 0, 1, 2, 3 and 6 h, respectively, from the inner canthus of rats to measure the serum uric acid, hemorheological parameters and the malondialdehyde level. It was found that in each period of 1, 2 and 3 h, the rats had significantly higher levels of uric acid. The integrated deformation index and relax index were increased. The hemolysis rate was significantly reduced. The plasma malondialdehyde level was obviously decreased at the end of 2 h. The results suggested that short-term elevated uric acid could improve the hemorheological parameters and the lipid oxidative level in red blood cells.

The membrane skeleton of mature erythrocyte is formed during erythroid differentiation. Fluid shear stress is one of the main factors that promote embryonic hematopoiesis, however, its effects on erythroid differentiation and cytoskeleton remodeling are unclear. Erythrocyte tropomodulin of 41 kDa (E-Tmod41) caps the pointed end of actin filament (F-actin) and is critical for the formation of hexagonal topology of erythrocyte membrane skeleton. Our study focused on the regulation of E-Tmod41 and its role in F-actin cytoskeleton remodeling during erythroid differentiation induced by fluid shear stress. Mouse erythroleukemia (MEL) cells and embryonic erythroblasts were subjected to fluid shear stress (5 dyn/cm2) and erythroid differentiation was induced in both cells. F-actin content and E-Tmod41 expression were significantly increased in MEL cells after shearing. E-Tmod41 overexpression resulted in a significant increase in F-actin content, while the knockdown of E-Tmod41 generated the opposite result. An E-Tmod 3'UTR targeting miRNA, miR-23b-3p, was found suppressed by shear stress. When miR-23b-3p level was overexpressed / inhibited, both E-Tmod41 protein level and F-actin content were reduced / augmented. Furthermore, among the two alternative promoters of E-Tmod, PE0 (upstream of exon 0), which mainly drives the expression of E-Tmod41, was found activated by shear stress. In conclusion, our results suggest that fluid shear stress could induce erythroid differentiation and F-actin cytoskeleton remodeling. It upregulates E-Tmod41 expression through miR-23b-3p suppression and PE0 promoter activation, which, in turn, contributes to F-actin cytoskeleton remodeling.

Interlukin-10 (IL-10) is an immunomodulatory cytokine which predominantly induces immune-tolerance. It has been also identified as a major cytokine in the tumor microenvironment that markedly mediates tumor immune escape. Previous studies on the roles of IL-10 in tumor immunosuppression mainly focus on its biochemical effects. But the effects of IL-10 on the biophysical characteristics of immune cells are ill-defined. Dendritic cells (DCs) are the most potent antigen-presenting cells and play a key role in the anti-tumor immune response. IL-10 can affect the immune regulatory functions of DCs in various ways. In this study, we aim to explore the effects of IL-10 on the biophysical functions of mature DCs (mDCs). mDCs were treated with different concentrations of IL-10 and their biophysical characteristics were identified. The results showed that the biophysical properties of mDCs, including electrophoresis mobility, osmotic fragility and deformability, as well as their motilities, were impaired by IL-10. Meanwhile, the cytoskeleton (F-actin) of mDCs was reorganized by IL-10. IL-10 caused the alternations in the expressions of fasin1 and profilin1 as well as the phosphorylation of cofilin1 in a concentration-dependent fashion. Moreover, Fourier transformed infrared resonance data showed that IL-10 made the status of gene transcription and metabolic turnover of mDCs more active. These results demonstrate a new aspect of IL-10’s actions on the immune system and represent one of the mechanisms for immune escape of tumors. It may provide a valuable clue to optimize and improve the efficiency of DC-based immunotherapy against cancer.