ABSTRACT
BACKGROUND: Metabolic associated fatty liver disease (MAFLD), a prevalent liver disorder affecting one-third of the global population, encompasses a spectrum ranging from fatty liver to severe hepatic steatosis. Both genetic and lifestyle factors, particularly diet and nutrition, contribute to its etiology. Folate deficiency, a frequently encountered type of malnutrition, has been associated with the pathogenesis of MAFLD and shown to impact lipid deposition. However, the underlying mechanisms of this relationship remain incompletely understood. We investigated the impact of disturbed folate-mediated one-carbon metabolism (OCM) on hepatic lipid metabolism both in vitro using human hepatoma cells and in vivo using transgenic fluorescent zebrafish displaying extent-, stage-, and duration-controllable folate deficiency upon induction. RESULTS: Disturbed folate-mediated one-carbon metabolism, either by inducing folate deficiency or adding anti-folate drug, compromises autophagy and causes lipid accumulation in liver cells. Disturbed folate status down-regulates cathepsin L, a key enzyme involved in autophagy, through inhibiting mTOR signaling. Interfered mitochondrial biology, including mitochondria relocation and increased fusion-fission dynamics, also occurs in folate-deficient hepatocytes. Folate supplementation effectively mitigated the impaired autophagy and lipid accumulation caused by the inhibition of cathepsin L activity, even when the inhibition was not directly related to folate deficiency. CONCLUSIONS: Disruption of folate-mediated OCM diminishes cathepsin L expression and impedes autophagy via mTOR signaling, leading to lipid accumulation within hepatocytes. These findings underscore the crucial role of folate in modulating autophagic processes and regulating lipid metabolism in the liver.
Subject(s)
Autophagy , Folic Acid , Hepatocytes , Homeostasis , Lipid Metabolism , Zebrafish , Autophagy/physiology , Folic Acid/metabolism , Humans , Hepatocytes/metabolism , Animals , Folic Acid Deficiency/metabolismABSTRACT
This paper describes a room response equalization technique based on an underdetermined multichannel inverse filtering (UMIF) and linearly constrained minimum variance (LCMV) approach. Not limited to the local control at the neighborhood of the measured control points, the proposed UMIF-LCMV system is capable of widening the effective equalization area of the reproduced sound field, with a large number of interpolated control points. Specifically, a constrained optimization problem is formulated to minimize the matching error at the interpolated control points while seeking precise matching at the measured control points. In practical implementation, only the frequency responses (FRs) associated with a limited number of control points need to be measured, whereas the FRs for the interpolated points are established by using a plane wave decomposition-based sensor interpolation technique. A two-stage procedure is developed to trim down plane wave components by using the least absolute shrinkage and selection operator (LASSO) algorithm and to obtain the complex amplitudes of the principal components. Simulations and objective and subjective experiments are conducted for a system comprising a linear loudspeaker array and a linear microphone array. The results have confirmed the efficacy of the proposed system in widening the effective listening area with only limited discrete measurements.
ABSTRACT
INTRODUCTION: This study compared the casualties and types of rescues conducted on the main climbing route (MCR) and accessory climbing routes (ACRs) in Yushan National Park (YSNP) between 2008 and 2019. METHODS: We collected the following information for all documented mountain rescue operations conducted on the MCRs and ACRs in YSNP between 2008 and 2019: accident location, casualty type, victim number, and type of rescue. The victims were categorized as to injury, illness, mortality, or no medical problem (NMP) groups according to their condition at the time of rescue. RESULTS: Two-hundred forty-four rescue operations involving 329 victims were conducted during the 12-y study period. Among them, 105 (32%) did not require medical treatment, 102 (31%) were injured, 82 (25%) were ill, and 40 (12%) were deceased. Of the 82 individuals with illness, 69 (84%) had acute altitude sickness. The accident and mortality rates on the ACRs were significantly higher than those on the MCR (P<0.001; χ2). The ACR incidents involved significantly higher percentages of helicopter-based rescues and victims in the NMP group (P<0.001). CONCLUSIONS: Acute altitude sickness accounted for most of the rescues. ACRs had higher injury and mortality rates and required more helicopter-based rescues for patients who did not have medical problems. This study may serve as a reference to reduce casualties and overuse of helicopters by educating tourists on the appropriate use of maps and the evaluation of trails in relation to weather conditions.
Subject(s)
Air Ambulances , Altitude Sickness , Emergency Medical Services , Aircraft , Altitude Sickness/epidemiology , Altitude Sickness/therapy , Humans , Parks, Recreational , Rescue Work , Retrospective StudiesABSTRACT
MoS2 quantum dots (QDs)-based white-light-emitting diodes (QD-WLEDs) are designed, fabricated, and demonstrated. The highly luminescent, histidine-doped MoS2 QDs synthesized by microwave induced fragmentation of 2D MoS2 nanoflakes possess a wide distribution of available electronic states as inferred from the pronounced excitation-wavelength-dependent emission properties. Notably, the histidine-doped MoS2 QDs show a very strong emission intensity, which exceeds seven times of magnitude larger than that of pristine MoS2 QDs. The strongly enhanced emission is mainly attributed to nitrogen acceptor bound excitons and passivation of defects by histidine-doping, which can enhance the radiative recombination drastically. The enabled electroluminescence (EL) spectra of the QD-WLEDs with the main peak around 500 nm are found to be consistent with the photoluminescence spectra of the histidine-doped MoS2 QDs. The enhanced intensity of EL spectra with the current increase shows the stability of histidine-doped MoS2 based QD-WLEDs. The typical EL spectrum of the novel QD-WLEDs has a Commission Internationale de l'Eclairage chromaticity coordinate of (0.30, 0.36) exhibiting an intrinsic broadband white-light emission. The unprecedented and low-toxicity QD-WLEDs based on a single light-emitting material can serve as an excellent alternative for using transition metal dichalcogenides QDs as next generation optoelectronic devices.
ABSTRACT
The leukocyte adhesion cascade involves multiple events that efficiently localize circulating leukocytes into the injured sites to mediate inflammatory responses. From rolling to firm adhesion, the interactions between adhesion molecules have pivotal roles in increasing the avidity of leukocytes to endothelial cells. Thrombomodulin (TM), an essential anticoagulant protein in the vasculature, is also expressed on leukocytes. We previously demonstrated that Lewisy (Ley), a specific ligand of TM, is upregulated in inflamed endothelium and is involved in leukocyte adhesion. The current study aimed to investigate whether leukocyte-expressed TM promotes cell adhesion by interacting with Ley. Using human monocytic THP-1 cells as an in vitro cell model, we showed that TM increases THP-1 cell adhesion to inflamed endothelium as well as to Ley-immobilized surface. When THP-1 adhered to activated endothelium and Ley-immobilized surface, the TM distribution became polarized. Addition of soluble Ley to a suspension of THP-1 cells with TM expression triggered an increase in the level of phosphorylated p38 mitogen-activated protein kinase (MAPK), which enabled THP-1 to adhere firmly to intercellular adhesion molecule (ICAM)-1 by activating ß2 integrins. In vivo, macrophage infiltration and neointima formation following arterial ligation-induced vascular injury were higher in wild-type TM (TMflox/flox) than in myeloid-specific TM-deficient (LysMcre/TMflox/flox) mice. Taken together, these results suggest a novel function for TM as an adhesion molecule in monocytes, where it enhances cell adhesion by binding Ley, leading to ß2 integrin activation via p38 MAPK.
Subject(s)
Endothelial Cells/immunology , Inflammation/immunology , Monocytes/immunology , Neointima/immunology , Thrombomodulin/metabolism , Animals , CD18 Antigens/metabolism , Cell Adhesion , Disease Models, Animal , Humans , Intercellular Adhesion Molecule-1/metabolism , Lewis Blood Group Antigens/metabolism , Ligands , Mice , Mice, Knockout , RNA, Small Interfering/genetics , Signal Transduction , THP-1 Cells , Thrombomodulin/agonists , Thrombomodulin/genetics , Up-Regulation , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
A novel citrinin derivative, penicitrinol L (1), along with two known analogues, penidicitrinin B (2) and pennicitrinone A (3) were isolated from the marine-source fungus Penicillium citrinum. The structure of the new compound was elucidated by spectroscopic methods including one and two-dimensional NMR as well as high-resolution mass spectrometric analysis. Furthermore, compound 1 showed modest cytotoxic activity against HL-60 cell line and compound 3 showed weak cytotoxic activity against A375 cell line.
Subject(s)
Citrinin/analogs & derivatives , Penicillium/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Citrinin/chemistry , Citrinin/isolation & purification , HL-60 Cells , Humans , Magnetic Resonance SpectroscopyABSTRACT
BACKGROUND: Obesity is a worldwide epidemic that threats the health and body image of those who suffer from this condition. While bariatric surgery has been shown to effectively assist patients to achieve weight loss goals and to improve body image, related research on this intervention is lacking in Taiwan. PURPOSE: The purpose of this research is to investigate the effect of bariatric surgery on body image in obese patients. METHODS: This study used a longitudinal design. Data was collected from 2 hospitals located in northern and southern Taiwan. A total of 56 obese patients who had undergone bariatric surgery enrolled as participants, and the completion rate was 93.3%. Participants responded to a validated body image questionnaire immediately prior to and 3 months after bariatric surgery, with data used to assess the effects of the surgery. SPSS 20.0 software for windows was used for data analysis. RESULTS: Participant scores for body image were low on the questionnaire administered prior to surgery, with a significant negative correlation identified between body mass index (BMI) and the value of appearance (r = -.36, p < .01). After bariatric surgery, the average EWL was 42.08%, which effectively achieved expected weight loss goals. Variables including overall body image, appearance evaluation, orientation, and body satisfaction of participants were significantly improved. Only the variable of muscle tension did not improve significantly. Postoperative body image did not correlate with either BMI or EWL. CONCLUSIONS: Three months after the bariatric surgery, the body image, appearance evaluation, and physical appearance satisfaction of participants had significantly improved. However, there was no improvement in muscle tension scores. In order to improve the post-surgery body image of patients, we recommend that healthcare workers provide patients with proper expectations of bariatric surgery and teach patients appropriate muscle-tension exercises. This paper reports the relation between bariatric surgery and body image. The results provide evidence for clinical and future research in this field.
Subject(s)
Bariatric Surgery , Body Image , Obesity/surgery , Adult , Body Mass Index , Female , Humans , Male , Middle Aged , Weight LossABSTRACT
OBJECTIVE: The N-terminal lectin-like domain (domain 1 [D1]) of thrombomodulin (TM) is known to have an anti-inflammatory function. We previously showed that recombinant TM domain 1 (rTMD1) interacts with a carbohydrate molecule, Lewis Y (Le(y)), which is found to be expressed on adhesion molecules and involved in cell adhesion. Here, we tested the effect of rTMD1/Le(y) interaction on leukocyte recruitment in inflammation. APPROACH AND RESULTS: The expression of Le(y) on the surface of human umbilical vein endothelial cells was increased by tumor necrosis factor-α stimulation. Direct binding of rTMD1 to Le(y) on the cell surface was observed. rTMD1 inhibited Le(y)-mediated leukocyte adhesion on the Le(y)-immobilized flow chamber and activated endothelium under a shear flow. The following leukocyte transmigration to endothelium was also reduced by rTMD1 through binding Le(y). In vivo, treatment of rTMD1 reduced leukocyte recruitment to the inflammatory sites in carotid ligation injury and thioglycollate-induced peritonitis. rTMD1 administration in apolipoprotein E-deficient mice effectively suppressed atherosclerotic plaque formation and macrophage infiltration in atherosclerotic lesions. Increased Le(y) expression, as well as administered rTMD1, was observed in inflamed vessels. CONCLUSIONS: rTMD1 suppresses vascular inflammation by inhibiting leukocyte recruitment to endothelium through attenuating Le(y)-mediated adhesion and further protects against atherosclerosis progression. The present study provides a mechanism showing that rTMD1 can inhibit inflammation by binding to its carbohydrate ligand Le(y).
Subject(s)
Anti-Inflammatory Agents/administration & dosage , Atherosclerosis/prevention & control , Chemotaxis, Leukocyte/drug effects , Endothelial Cells/drug effects , Leukocytes, Mononuclear/drug effects , Lewis Blood Group Antigens/metabolism , Neutrophils/drug effects , Thrombomodulin/administration & dosage , Vasculitis/prevention & control , Animals , Anti-Inflammatory Agents/metabolism , Apolipoproteins E/deficiency , Apolipoproteins E/genetics , Atherosclerosis/immunology , Atherosclerosis/metabolism , Atherosclerosis/pathology , Carotid Artery Injuries/immunology , Carotid Artery Injuries/metabolism , Carotid Artery Injuries/pathology , Cell Adhesion/drug effects , Cell Line, Tumor , Coculture Techniques , Disease Models, Animal , Dose-Response Relationship, Drug , Endothelial Cells/immunology , Endothelial Cells/metabolism , Endothelial Cells/pathology , HEK293 Cells , Human Umbilical Vein Endothelial Cells/immunology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Lewis Blood Group Antigens/immunology , Macrophages/drug effects , Macrophages/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophils/immunology , Neutrophils/metabolism , Plaque, Atherosclerotic , Protein Structure, Tertiary , Recombinant Proteins/administration & dosage , Thrombomodulin/metabolism , Transendothelial and Transepithelial Migration/drug effects , Tumor Necrosis Factor-alpha/metabolism , Vasculitis/immunology , Vasculitis/metabolism , Vasculitis/pathologyABSTRACT
Podocalyxin was initially identified in glomerular podocytes to critically maintain the structural and functional integrity of the glomerular ultrafiltrative apparatus. Lately, it has emerged as a malignant marker in tumors arising from a variety of tissue origins. By immunohistochemistry, we identified that 9.6% of renal cell carcinoma patients overexpress this protein. This subset of patients had significantly shorter disease-specific and overall survivals, and, importantly, we established podocalyxin overexpression as an independent prognostic factor for latent distant metastasis with multivariate analysis. Podocalyxin down-regulation by small interfering RNA led to defective migration in model renal tubular cells, which was corrected by re-expression of podocalyxin. The activity of the small GTPase Rac1, a well-characterized modulator of cell migration, was diminished by podocalyxin knock-down. Conversely, podocalyxin overexpression in human embryonic kidney cells up-regulated Rac1 activity, which depended on a complex formed by podocalyxin, ERM-binding phosphoprotein 50, ezrin, and ARHGEF7, a Rac1 activator. Therefore, podocalyxin can serve as a biomarker to identify renal cell carcinoma patients with higher metastatic potential for more aggressive intervention at earlier clinical stages.
Subject(s)
Carcinoma, Renal Cell/pathology , Cytoskeletal Proteins/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Multiprotein Complexes/metabolism , Phosphoproteins/metabolism , Sialoglycoproteins/metabolism , Sodium-Hydrogen Exchangers/metabolism , rac1 GTP-Binding Protein/metabolism , Adult , Aged , Animals , Carcinoma, Renal Cell/metabolism , Cell Adhesion/physiology , Cell Line , Cell Movement/physiology , Cytoskeletal Proteins/genetics , Dogs , Enzyme Activation , Female , Gene Knockdown Techniques , Guanine Nucleotide Exchange Factors/genetics , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Metastasis , Phosphoproteins/genetics , Rho Guanine Nucleotide Exchange Factors , Sialoglycoproteins/genetics , Sodium-Hydrogen Exchangers/genetics , rac1 GTP-Binding Protein/geneticsABSTRACT
Vascular calcification is a major risk factor for cardiovascular morbidity and mortality. To develop appropriate prevention and/or therapeutic strategies for vascular calcification, it is important to understand the origins of the cells that participate in this process. In this report, we used the SM22-Cre recombinase and Rosa26-LacZ alleles to genetically trace cells derived from smooth muscle. We found that smooth muscle cells (SMCs) gave rise to osteochondrogenic precursor- and chondrocyte-like cells in calcified blood vessels of matrix Gla protein deficient (MGP(-/-)) mice. This lineage reprogramming of SMCs occurred before calcium deposition and was associated with an early onset of Runx2/Cbfa1 expression and the downregulation of myocardin and Msx2. There was no change in the constitutive expression of Sox9 or bone morphogenetic protein 2. Osterix, Wnt3a, and Wnt7a mRNAs were not detected in either calcified MGP(-/-) or noncalcified wild-type (MGP(+/+)) vessels. Finally, mechanistic studies in vitro suggest that Erk signaling might be required for SMC transdifferentiation under calcifying conditions. These results provide strong support for the hypothesis that adult SMCs can transdifferentiate and that SMC transdifferentiation is an important process driving vascular calcification and the appearance of skeletal elements in calcified vascular lesions.
Subject(s)
Arteries/metabolism , Calcinosis/metabolism , Chondrocytes/metabolism , Myocytes, Smooth Muscle/metabolism , Stem Cells/metabolism , Vascular Diseases/metabolism , Animals , Arteries/pathology , Bone Morphogenetic Protein 2/genetics , Bone Morphogenetic Protein 2/metabolism , Calcinosis/genetics , Calcinosis/pathology , Cell Dedifferentiation/genetics , Chondrocytes/pathology , Core Binding Factor Alpha 1 Subunit/genetics , Core Binding Factor Alpha 1 Subunit/metabolism , Down-Regulation/genetics , Extracellular Signal-Regulated MAP Kinases/genetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , MAP Kinase Signaling System/genetics , Mice , Mice, Knockout , Mice, Mutant Strains , Myocytes, Smooth Muscle/pathology , Proteins/genetics , Proteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , SOX9 Transcription Factor/genetics , SOX9 Transcription Factor/metabolism , Sp7 Transcription Factor , Stem Cells/pathology , Transcription Factors/genetics , Transcription Factors/metabolism , Vascular Diseases/genetics , Vascular Diseases/pathology , Wnt Proteins/genetics , Wnt Proteins/metabolism , Wnt3 Protein , Wnt3A ProteinABSTRACT
Podocalyxin/Gp135 was recently demonstrated to participate in the formation of a preapical complex to set up initial polarity in MDCK cells, a function presumably depending on the apical targeting of Gp135. We show that correct apical sorting of Gp135 depends on a bipartite signal composed of an extracellular O-glycosylation-rich region and the intracellular PDZ domain-binding motif. The function of this PDZ-binding motif could be substituted with a fusion construct of Gp135 with Ezrin-binding phosphoprotein 50 (EBP50). In accordance with this observation, EBP50 binds to newly synthesized Gp135 at the Golgi apparatus and facilitates oligomerization and sorting of Gp135 into a clustering complex. A defective connection between Gp135 and EBP50 or EBP50 knockdown results in a delayed exit from the detergent-resistant microdomain, failure of oligomerization, and basolateral missorting of Gp135. Furthermore, the basolaterally missorted EBP50-binding defective mutant of Gp135 was rapidly retrieved via a PKC-dependent mechanism. According to these findings, we propose a model by which a highly negative charged transmembrane protein could be packed into an apical sorting platform with the aid of its cytoplasmic partner EBP50.
Subject(s)
Sialoglycoproteins/metabolism , Amino Acid Motifs , Animals , Base Sequence , Binding Sites , Carrier Proteins/antagonists & inhibitors , Carrier Proteins/genetics , Cell Polarity , Cells, Cultured , Cytoskeletal Proteins/metabolism , Dogs , Endocytosis , Glycosylation , Membrane Microdomains/metabolism , Models, Biological , Mutation , Protein Kinase C/metabolism , Protein Sorting Signals/genetics , Protein Structure, Tertiary , RNA, Small Interfering/genetics , Sialoglycoproteins/chemistry , Sialoglycoproteins/genetics , Signal TransductionABSTRACT
Hepatitis B is the most prevalent viral hepatitis worldwide, affecting approximately one-third of the world's population. Among HBV factors, the surface protein is the most sensitive biomarker for viral infection, given that it is expressed at high levels in all viral infection phases. The large HBV surface protein (LHBs) contains the integral pre-S1 domain, which binds to the HBV receptor sodium taurocholate co transporting polypeptide on the hepatocyte to facilitate viral entry. The accumulation of viral LHBs and its prevalent pre-S mutants in chronic HBV carriers triggers a sustained endoplasmic reticulum (ER) overload response, leading to ER stress-mediated cell proliferation, metabolic switching and genomic instability, which are associated with pro-oncogenic effects. Ground glass hepatocytes identified in HBV-related hepatocellular carcinoma (HCC) patients harbor pre-S deletion variants that largely accumulate in the ER lumen due to mutation-induced protein misfolding and are associated with increased risks of cancer recurrence and metastasis. Moreover, in contrast to the major HBs, which is decreased in tumors to a greater extent than it is in peritumorous regions, LHBs is continuously expressed during tumorigenesis, indicating that LHBs serves as a promising biomarker for HCC in people with CHB. Continuing efforts to delineate the molecular mechanisms by which LHBs regulates pathological changes in CHB patients are important for establishing a correlation between LHBs biomarkers and HCC development.
Subject(s)
Carcinoma, Hepatocellular/virology , Hepatitis B virus/pathogenicity , Liver Neoplasms/virology , Carcinoma, Hepatocellular/pathology , Endoplasmic Reticulum Stress , Hepatitis B virus/metabolism , Humans , Liver Neoplasms/pathologyABSTRACT
Dynamic processes such as fusion, fission, and trafficking are important in the regulation of cellular organelles, with an abundant literature focused on mitochondria. Mitochondrial dynamics not only help shape its network within cells but also are involved in the modulation of respiration and integrity. Disruptions of mitochondrial dynamics are associated with neurodegenerative disorders. Although proteins that directly bind mitochondria to promote membrane fusion/fission have been studied intensively, machineries that regulate dynamic mitochondrial processes remain to be explored. We have identified an interaction between the mitochondrial fission GTPase Dnm1/DRP1 and the actin-regulatory protein Srv2/CAP at mitochondria. Deletion of Srv2 causes elongated-hyperfused mitochondria and reduces the reserved respiration capacity in yeast cells. Our results further demonstrate that the irregular network morphology in Δsrv2 cells derives from disrupted actin assembly at mitochondria. We suggest that Srv2 functions as a pro-fission factor in shaping mitochondrial dynamics and regulating activity through its actin-regulatory effects.
ABSTRACT
Oral cancer with high incidence rates is occurring in many countries including in India, Pakistan, Bangladesh, Sri Lanka and Taiwan. Smoking, alcoholism, and betel nut chewing are considered to be the main risk factors for oral cancer. Further, deaths from oral cancer have increased year by year. Although several oral cancer-associated biomarkers have been reported, very few useful biomarkers have been applied for early diagnosis. Therefore, the investigation of oral cancer-specific biomarkers is urgently needed. We previously investigated N-glycomes of oral cancer cells and patient plasma. We found that both mRNA levels of FUT8 and core-fucosylated glycoproteins increase in cases of oral cancer relative to normal cases. In this study we aim to discover novel core-fucosylated glycoprotein biomarkers for oral cancer diagnosis with glycoproteomic approaches. First, forty plasma samples obtained from the Human Bioinformation Bank of NCKUH were subjected to AAL (Aleuria aurantia lectin) affinity chromatography. Core-fucosylated proteins were collected and applied for LC-MS/MS followed by electrophoresis. Fourteen proteins were identified, and expression levels of proteins in plasma were verified by western blot. Expression levels of some glycoproteins were elevated in the oral cancer group, including ceruloplasmin, haptoglobin, and leucin-rich alpha-2-glycoprotein 1 (LRG1). However, levels of some glycoproteins decreased in the cancer group, including apolipoprotein A-I (apo A-I) and apolipoprotein A-IV (apo A-IV). Via ELISA analysis, we found that apo A-IV and apo A-IV/total protein ratios were decreased in plasma accompanied with cancer stages. The LRG1/total protein ratio was found to increase while plasma levels of LRG1 were not found to differ between the oral cancer plasma and normal groups. An ROC curve analysis reveals strong diagnosis performance when combining apo A-IV levels and LRG1/total protein ratios. Taken together, apo A-IV and LRG1, given their strong performance in detecting oral cancer, can serve as useful biomarkers and may be used as a useful tool for oral cancer screening and early diagnosis.
Subject(s)
Biomarkers, Tumor/blood , Glycoproteins/blood , Mouth Neoplasms/blood , Proteomics , Adult , Computational Biology , Electrophoresis, Polyacrylamide Gel , Female , Humans , Male , Mass Spectrometry , Mouth Neoplasms/diagnosis , ROC CurveABSTRACT
Aberrant glycosylation changes normal cellular functions and represents a specific hallmark of cancer. Lewisy (Ley) carbohydrate upregulation has been reported in a variety of cancers, including oral squamous cell carcinoma (OSCC). A high level of Ley expression is related to poor prognosis of patients with oral cancer. However, it is unclear how Ley mediates oral cancer progression. In this study, the role of Ley in OSCC was explored. Our data showed that Ley was upregulated in HSC-3 and OC-2 OSCC cell lines. Particularly, glycosylation of epidermal growth factor receptor (EGFR) with Ley was found in OC-2 cells, and this modification was absent upon inhibition of Ley synthesis. The absence of Ley glycosylation of EGFR weakened phosphorylation of AKT and ERK in response to epidermal growth factor (EGF). Additionally, EGF-triggered cell migration was reduced, but cell proliferation was not affected. Ley modification stabilized EGFR upon ligand activation. Conversely, absence of Ley glycosylation accelerated EGFR degradation. In summary, these results indicate that increased expression of Ley in OSCC cells is able to promote cell migration by modifying EGFR which in turn stabilizes EGFR expression and downstream signaling. Targeting Ley on EGFR could have a potential therapeutic effect on oral cancer.
Subject(s)
Carcinoma, Squamous Cell/metabolism , Cell Movement , ErbB Receptors/metabolism , Lewis Blood Group Antigens/metabolism , Mouth Neoplasms/metabolism , Protein Processing, Post-Translational , Cell Line, Tumor , Cells, Cultured , Extracellular Signal-Regulated MAP Kinases/metabolism , Glycosylation , Humans , Keratinocytes/metabolism , Keratinocytes/physiology , Lewis Blood Group Antigens/genetics , Male , Proto-Oncogene Proteins c-akt/metabolismABSTRACT
Molecules derived from cinnamon have demonstrated diverse pharmacological activities against infectious pathogens, diabetes and inflammatory diseases. This study aims to evaluate the effect of the cinnamon-derived molecule IND02 on the adhesion of leukocytes to host cells. The anti-inflammatory ability of IND02, a pentameric procyanidin type A polyphenol polymer isolated from cinnamon alcohol extract, was examined. Pretreatment with IND02 significantly reduced the attachment of THP-1 cells or neutrophils to TNF-α-activated HUVECs or E-selectin/ICAM-1, respectively. IND02 also reduced the binding of E-, L- and P-selectins with sialosides. Furthermore, IND02 could agglutinate human red blood cells (RBC), and the agglutination could be disrupted by sialylated glycoprotein. Our findings demonstrate that IND02, a cinnamon-derived compound, can interact with sialosides and block the binding of selectins and leukocytes with sialic acids.
Subject(s)
Cell Adhesion/drug effects , Cinnamomum zeylanicum/metabolism , Erythrocyte Aggregation/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Neutrophils/metabolism , Proanthocyanidins/pharmacology , Agglutination/drug effects , Anti-Inflammatory Agents/pharmacology , Cell Line, Tumor , Drugs, Chinese Herbal/pharmacology , E-Selectin/metabolism , Endothelium, Vascular/metabolism , Erythrocytes/drug effects , Humans , Inflammation/drug therapy , Intercellular Adhesion Molecule-1/metabolism , N-Acetylneuraminic Acid/metabolism , Orthomyxoviridae/metabolism , Protein Binding/drug effects , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Keratinocyte-expressed thrombomodulin (TM) and the released soluble TM (sTM) have been demonstrated to promote wound healing. However, the effects of high glucose on TM expression in keratinocytes and the role of TM in diabetic ulcer remain unclear. In this study, we demonstrated that expressions of TM and Toll-like receptor 4 (TLR4) were both downregulated in high-glucose cultured human keratinocytes and in skin keratinocytes of diabetic patients. In addition, the wound-triggered upregulation of TM and sTM production was abolished in both high-glucose cultured human keratinocytes and streptozotocin-induced diabetic mouse skin. Furthermore, supplementation of recombinant sTM could increase TLR4 expression and promote cutaneous wound healing in both high-glucose cultured human keratinocytes and diabetic mice. However, in Tlr4-deleted mice, which exhibited delayed wound healing, the therapeutic benefit of recombinant sTM was abrogated. Moreover, our results showed that tumor necrosis factor-α (TNF-α) expression in keratinocytes was dose-dependently upregulated by glucose, and TNF-α treatment downregulated the expression of TM and TLR4. Taken together, high-glucose environment reduces the expression of TM and TLR4 in keratinocytes possibly through the action of TNF-α, and recombinant sTM can increase the TLR4 expression and promote wound healing under diabetic condition.
Subject(s)
Diabetes Complications/metabolism , Diabetes Mellitus, Experimental/metabolism , Thrombomodulin/physiology , Toll-Like Receptor 4/metabolism , Wound Healing , Animals , Cell Line, Tumor , Gene Deletion , Gene Expression Regulation , Glucose/chemistry , Humans , Keratinocytes/cytology , Keratinocytes/drug effects , Keratinocytes/metabolism , Mice , Mice, Inbred C57BL , Recombinant Proteins/metabolism , Skin/metabolism , Streptozocin/chemistry , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Solamargine (SM), isolated from Solanum incanum herb, displayed a superior cytotoxicity in four human lung cancer cell lines. The half-inhibitory concentrations (IC50), of the cell viability assay for H441, H520, H661 and H69 cells were 3, 6.7, 7.2 and 5.8 microM, respectively. SM-induced apoptosis of these cells by PS externalization in a dose-dependent manner and increased sub-G1 fraction were observed. Quenching of the expression of tumor necrosis factor receptors (TNFRs) during the progress of human lung carcinogenesis has been previously reported. SM may induce cell apoptosis via modulating the expression of TNFRs and their subsequent TRADD/FADD signal cascades. Subsequently, SM treatment increased the binding activities of TNF-alpha and TNF-beta to the lung cancers, and the intrinsic TNFs-resistant cancer cells became susceptible to TNF-alpha and -beta. In addition, SM caused release of cytochrome c, downregulation of anti-apoptotic Bcl-2 and Bcl-xL, increase of caspase-3 activity, and DNA fragmentation. Thus, SM could modulate the expressions of TNFRs and Bcl-2, and might be a potential anticancer agent for TNFs and Bcl-2 related resistance of human lung cancer cells.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cell Division/drug effects , Lung Neoplasms/pathology , Solanaceous Alkaloids/pharmacology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type II/geneticsABSTRACT
The membrane glycoprotein thrombomodulin (TM) has been implicated in keratinocyte differentiation and wound healing, but its specific function remains undetermined. The epidermis-specific TM knockout mice were generated to investigate the function of TM in these biological processes. Primary cultured keratinocytes obtained from TM(lox/lox); K5-Cre mice, in which TM expression was abrogated, underwent abnormal differentiation in response to calcium induction. Poor epidermal differentiation, as evidenced by downregulation of the terminal differentiation markers loricrin and filaggrin, was observed in TM(lox/lox); K5-Cre mice. Silencing TM expression in human epithelial cells impaired calcium-induced extracellular signal-regulated kinase pathway activation and subsequent keratinocyte differentiation. Compared with wild-type mice, the cell spreading area and wound closure rate were lower in keratinocytes from TM(lox/lox); K5-Cre mice. In addition, the lower density of neovascularization and smaller area of hyperproliferative epithelium contributed to slower wound healing in TM(lox/lox); K5-Cre mice than in wild-type mice. Local administration of recombinant TM (rTM) accelerated healing rates in the TM-null skin. These data suggest that TM has a critical role in skin differentiation and wound healing. Furthermore, rTM may hold therapeutic potential for the treatment of nonhealing chronic wounds.
Subject(s)
Keratinocytes/cytology , Keratinocytes/physiology , Thrombomodulin/genetics , Thrombomodulin/metabolism , Wound Healing/physiology , Animals , Calcium/metabolism , Cell Differentiation/physiology , Cell Line , Cell Movement/physiology , Epidermal Cells , Epidermis/physiology , Filaggrin Proteins , Humans , MAP Kinase Signaling System/physiology , Mice , Mice, Knockout , Neovascularization, Physiologic/physiology , Phosphorylation/physiology , Primary Cell CultureABSTRACT
Podocalyxin (PC) was initially identified as a major sialoprotein on the apical surface of glomerular podocytes to perform the filtration barrier function. Later, it was reported to be expressed in endothelial cells, megakaryotes/platelets, and hemangioblasts, the common progenitor cells of the hematopoietic and endothelial cells. Recently, increasing numbers of reports have indicated that PC is not merely a molecule restricted at renal glomerulus, angiogenic or hematopoietic system. To further elucidate the expression pattern and address the possible physiological role of PC in adult mammals, we conducted an extensive study by immunohistochemistry and immunofluorescence staining on various tissues of healthy adult beagle dogs. By combinatory usage of two different anti-podocalyxin antibodies recognizing distinct epitopes in PC, we have demonstrated that (1) PC is expressed in renal tubules, mesothelium, myocardium, striated muscles in tongue, esophagus and extraocular region, myoepithelial cells in esophagus and salivary glands, neurons, and ependyma, etc.; (2) there are at least three forms of PC proteins, depending upon the accessibility of two different PC antibodies, expressed in different organs/systems; and (3) a particular form of PC is distributed in a vesicle-like compartment in certain organs/systems, such as the central nervous system.