PURPOSE: The purpose of this study was to evaluate the correlation between the expression of claudins and prognostic factors in patients with prostate cancer. MATERIALS AND METHODS: The subjects of this study were 48 patients who had undergone surgery for prostate cancer. The Gleason score (6 or lower, 7 or higher), prostate-specific antigen (PSA) level, T stage, biochemical recurrence, local recurrence, and distant metastasis were compared according to the expression of claudin-1 and claudin-5 in prostate cancer. RESULTS: In the group with a low expression of claudin-1, the Gleason score was 7 points or higher in 18 cases (82%) and 6 points or lower in 4 cases (18%). In the group with a high expression of claudin-1, the Gleason score was 7 points or higher in 13 cases (50%) and 6 points or lower in 13 cases (50%). Thus, the low-expression group had more cases with a Gleason score of 7 or higher (p=0.022). The group with a low expression of claudin-5 also had more cases with a Gleason score of 7 or higher (p=0.011). The mean PSA values in the groups with a low and high expression of claudin-1 were 9.6 ng/ml and 5.6 ng/ml, respectively (p=0.007). A low expression of claudin-5 was also associated with a high PSA value (p=0.002). There was no statistical difference in the expression of claudin-1 and claudin-5 by T stage, biochemical recurrence, local recurrence, or distant metastasis. CONCLUSIONS: The low expression of claudin-1, claudin-5 was associated with a Gleason score of 7 or higher and a high PSA value in prostate cancer.
Claudin-1 ; Claudin-5 ; Claudins ; Humans ; Neoplasm Grading ; Neoplasm Metastasis ; Prostate ; Prostate-Specific Antigen ; Prostatic Neoplasms ; Recurrence

Claudins, which are known as transmembrane proteins play an essential role in tight junctions (TJs) to form physical barriers and regulate paracellular transportation. To understand equine diseases, it is helpful to measure the tissue-specific expression of TJs in horses. Major equine diseases such as colic and West Nile cause damage to TJs. In this study, the expression level and distribution of claudin-1, -2, -4, and -5 in eight tissues were assessed by Western blotting and immunohistochemistry methods. Claudin-1 was primarily identified in the lung, duodenum, and uterus, claudin-2 was evenly observed in equine tissues, claudin-4 was abundantly detected in the liver, kidney and uterus, and claudin-5 was strongly expressed in the lung, duodenum, ovary, and uterus, as determined by Western blotting method. The localization of equine claudins was observed by immunohistochemistry methods. These findings provide knowledge regarding the expression patterns and localization of equine claudins, as well as valuable information to understand tight junction-related diseases according to tissue specificity and function of claudins in horses.
Animals ; Architectural Accessibility ; Blotting, Western ; Claudin-1* ; Claudin-2 ; Claudin-4 ; Claudin-5 ; Claudins ; Colic ; Duodenum ; Female ; Horse Diseases ; Horses ; Immunohistochemistry ; Kidney ; Liver ; Lung ; Methods ; Organ Specificity ; Ovary ; Tight Junctions ; Transportation ; Uterus

PURPOSE: The tight junction protein claudin-5 (CLDN5) is critical to the control of endothelial cellular polarity and pericellular permeability. The role of CLDN5 in chronic obstructive pulmonary disease (COPD) remains unclear. The aim of this study was to investigate the association between CLDN5 levels and clinical variables in patients with COPD. METHODS: In total, 30 patients with COPD and 30 healthy controls were enrolled in the study. The plasma CLDN5 level was checked in patients with stable or exacerbated COPD and in healthy controls. RESULTS: The mean plasma CLDN5 level of patients with COPD was 0.63 ± 0.05 ng/mL and that of healthy controls was 6.9 ± 0.78 ng/mL (P = 0.001). The mean plasma CLDN5 level was 0.71 ± 0.05 ng/mL in exacerbated COPD patients and 0.63 ± 0.04 ng/mL in patients with stable COPD (P < 0.05). The plasma CLDN5 level among COPD subjects was correlated with the smoking amount (r = −0.530, P = 0.001). The plasma CLDN5 level in stable COPD patients was correlated with forced expiratory volume in one second (FEV1, %pred.) (r = −0.481, P = 0.037). CONCLUSIONS: The plasma CLDN5 level was not correlated with age. CLDN5 may be involved in the pathogenesis of COPD. Further studies having a larger sample size will be needed to clarify CLDN5 in COPD.
Claudin-5* ; Forced Expiratory Volume ; Humans ; Permeability ; Plasma ; Pulmonary Disease, Chronic Obstructive* ; Sample Size ; Smoke ; Smoking ; Tight Junctions*

This paper is aimed to investigate the effect of fluid shear stress on the tight junction of laryngeal squamous carcinoma (Hep2) cells and to explore the potential molecular mechanism. Hep2 cells were selected and subjected to the fluid shear stress of 1.4 dyn/cm2 for different time, respectively. The morphological changes of Hep2 cells under shear stress were observed using inverted microscope. The cell-cell junctions were examined by transmission electron microscope (TEM). The expressions of tight junction proteins (including Occludin, Claudin-5 and ZO-1) and the distribution of Claudin-5 were examined by Western blot assay and laser scanning confocal microscope, respectively. The results indicated that Hep2 cells turned to spindle-like shapes after exposed to shear stress, and showed the trend of the recovering to original shapes when the shear stress was cancelled. The cell-cell junctions were tight under the shear flow condition, and the permeability was reduced under the condition of 1.4 dyn/cm shear flow. The expressions of tight junction proteins were enhanced with increased duration of shear flow, but reduced after removing shear flow. The result of Claudin-5 expression by immufluorescence assay was consistent with that by Western blot. The Claudin-5 mainly distributed in the cytoplasm under static condition, while it located at the intercellular after shear flow stimulation, and it appeared intercellular and cytoplasm after stopping shear flow stimulation. Therefore, it can be concluded that shear stress changes the morphology of laryngeal squamous carcinoma Hep2 cells, and upregulates the tight junction.
Blotting, Western ; Carcinoma, Squamous Cell ; pathology ; Claudin-5 ; metabolism ; Hep G2 Cells ; Humans ; Laryngeal Neoplasms ; pathology ; Occludin ; metabolism ; Stress, Mechanical ; Tight Junctions ; Zonula Occludens-1 Protein ; metabolism

PURPOSE: To investigate the effects of high glucose (HG) and dexamethasone (DEX) on the survival and permeability of trabecular meshwork cells (HTMC), and associated changes in tight junctions. METHODS: Primary cultured HTMC were exposed to 5 mM low glucose (LG) or 25 mM HG with or without 1.0 µM DEX for 3 days. The permeability of the HTMC monolayer was assessed using carboxyfluorescein or transendothelial electrical resistance (TEER). Gene and protein expressions of claudin-5 and occludin were assessed with reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. RESULTS: HG was significantly associated with greater HTMC monolayer permeability compared to LG by both the carboxyfluorescein permeability test and TEER (p = 0.022, 0.028). HG also decreased claudin-5 and occludin mRNA expression, respectively (7.5%, 12.9%). DEX abolished HG-induced increased permeability, and increased the protein expression of claudin-5 and occludin, respectively (p = 0.015, 0.012). CONCLUSIONS: In HTMCs, DEX reversed HG-induced permeability increase. DEX increased tight junction molecules claudin-5 and occludin. Thus, DEX-induced changes in junctional proteins could be another mechanism of increased resistance through the trabecular meshwork and may result in steroid-induced glaucoma.
Blotting, Western ; Claudin-5 ; Dexamethasone ; Electric Impedance ; Glaucoma ; Glucose ; Occludin ; Permeability ; Polymerase Chain Reaction ; Reverse Transcription ; RNA, Messenger ; Tight Junctions ; Trabecular Meshwork

Resveratrol, a phytoalexin, is reported to activate AMP-activated protein kinase (AMPK) in vascular cells. The blood-brain barrier (BBB), formed by specialized brain endothelial cells that are interconnected by tight junctions, strictly regulates paracellular permeability to maintain an optimal extracellular environment for brain homeostasis. The aim of this study was to elucidate the effects of resveratrol and the role of AMPK in BBB dysfunction induced by lipopolysaccharide (LPS). Exposure of human brain microvascular endothelial cells (HBMECs) to LPS (1 µg/ml) for 4 to 24 hours week dramatically increased the permeability of the BBB in parallel with lowered expression levels of occluding and claudin-5, which are essential to maintain tight junctions in HBMECs. In addition, LPS significantly increased the reactive oxygen species (ROS) productions. All effects induced by LPS in HBVMCs were reversed by adenoviral overexpression of superoxide dismutase, inhibition of NAD(P) H oxidase by apocynin or gain-function of AMPK by adenoviral overexpression of constitutively active mutant (AMPK-CA) or by resveratrol. Finally, upregulation of AMPK by either AMPK-CA or resveratrol abolished the levels of LPS-enhanced NAD(P)H oxidase subunits protein expressions. We conclude that AMPK activation by resveratrol improves the integrity of the BBB disrupted by LPS through suppressing the induction of NAD(P)H oxidase-derived ROS in HBMECs.
AMP-Activated Protein Kinases* ; Blood-Brain Barrier* ; Brain ; Claudin-5 ; Endothelial Cells* ; Homeostasis ; Humans ; NADPH Oxidase ; Oxidoreductases ; Permeability ; Reactive Oxygen Species ; Superoxide Dismutase ; Tight Junctions ; Up-Regulation

OBJECTIVE: To investigate the protective effects and underlying mechanisms of Xuebijing Injection (XBJ) on the lung endothelial barrier in hydrogen sulfide (H METHODS: Sprague-Dawley rats were exposed to H RESULTS: The morphological investigation showed that XBJ attenuated H CONCLUSIONS XBJ ameliorated H
Animals ; Claudin-5 ; Drugs, Chinese Herbal ; Endothelial Cells ; Hydrogen Sulfide ; Phosphatidylinositol 3-Kinases ; Rats ; Rats, Sprague-Dawley ; Respiratory Distress Syndrome/drug therapy*

To determine whether indol-3-carbinol (I3C, C9H9NO), an autolysis product of a glucosinolate and a glucobrassicin in vegetables, regulated tight junction proteins (TJ) and suppressed cell invasion in colon cancer cells,this experiment was performed. Our results indicate that I3C inhibit cell growth of HT-29 cells in a dose (0, 50, 100 micrometer) and time (0, 24 and 48 h) dependent manner. Using the wound healing and matrigel invasion study, respectively, I3C inhibits the cell motility and invasion of the ovarian cancer cell line. The TEER values were increased in HT-29 cells grown in transwells treated with I3C, reversely, paracellular permeability was decreased in those of condition. Claudin-1, claudin-5, ZO-1 and occuldin have been shown to be positively expressed in HT-29 coloncancer cells. I3C occurs concurrently with a significant decrease in the levels of those of proteins in HT-29 cells. But E-cadherin level in the HT-29 was increased by I3C. The reduction of claudin-1 and claudin-5 protein levels occurred post-transcriptionaly since their mRNA levels are no difference by I3C. Therefore, our results suggest that I3C may be expected to inhibit cancer metastasis and invasion by tighten the cell junction and restoring tight junction in colon cancer cell line, HT-29.
Autolysis ; Cadherins ; Cell Line ; Cell Movement ; Claudin-1 ; Claudin-5 ; Collagen ; Colon ; Colonic Neoplasms ; Drug Combinations ; Glucosinolates ; HT29 Cells ; Humans ; Indoles ; Intercellular Junctions ; Laminin ; Neoplasm Metastasis ; Ovarian Neoplasms ; Permeability ; Proteins ; Proteoglycans ; RNA, Messenger ; Tight Junction Proteins ; Tight Junctions ; Vegetables ; Wound Healing

PURPOSE: The effect of air pollution-related particulate matter (PM) on epithelial barrier function and tight junction (TJ) expression in human nasal mucosa has not been studied to date. This study therefore aimed to assess the direct impact of PM with an aerodynamic diameter less than 2.5 μm (PM2.5) on the barrier function and TJ molecular expression of human nasal epithelial cells. METHODS: Air-liquid interface cultures were established with epithelial cells derived from noninflammatory nasal mucosal tissue collected from patients undergoing paranasal sinus surgery. Confluent cultures were exposed to 50 or 100 µg/mL PM2.5 for up to 72 hours, and assessed for 1) epithelial barrier integrity as measured by transepithelial resistance (TER) and permeability of fluorescein isothiocyanate (FITC) 4 kDa; 2) expression of TJs using real-time quantitative polymerase chain reaction and immunofluorescence staining, and 3) proinflammatory cytokines by luminometric bead array or enzyme-linked immunosorbent assay. RESULTS: Compared to control medium, 50 and/or 100 µg/mL PM2.5-treatment 1) significantly decreased TER and increased FITC permeability, which could not be restored by budesonide pretreatment; 2) significantly decreased the expression of claudin-1 messenger RNA, claudin-1, occludin and ZO-1 protein; and 3) significantly increased production of the cytokines interleukin-8, TIMP metallopeptidase inhibitor 1 and thymic stromal lymphopoietin. CONCLUSIONS: Exposure to PM2.5 may lead to loss of barrier function in human nasal epithelium through decreased expression of TJ proteins and increased release of proinflammatory cytokines. These results suggest an important mechanism of susceptibility to rhinitis and rhinosinusitis in highly PM2.5-polluted areas.
Asthma ; Budesonide ; Claudin-1 ; Cytokines ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells ; Fluorescein ; Fluorescein-5-isothiocyanate ; Fluorescent Antibody Technique ; Humans ; Interleukin-8 ; Mucous Membrane ; Nasal Mucosa ; Occludin ; Particulate Matter ; Permeability ; Polymerase Chain Reaction ; Rhinitis ; RNA, Messenger ; Tight Junctions

Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGF-A-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, β-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.
Actins ; Animals ; Capillary Permeability ; Choroid ; Choroidal Neovascularization ; Claudin-5 ; Endothelial Cells ; Endothelium ; Humans ; Macular Degeneration ; Mice ; Nitric Oxide Synthase Type III ; Permeability ; Phosphorylation ; Receptors, Vascular Endothelial Growth Factor ; Retinaldehyde ; Vascular Endothelial Growth Factor A