Objective To investigate the effect of salidroside on intestinal mucosal immune status in rats under compound stress of hypoxia and training (HTCS) and the mechanism. Methods SD rats were randomly divided into HTCS model group (model), placebo group (placebo) and salidroside group (salidro). Model group received no intervention, and placebo and salidro group received intraperitoneal injection of normal saline and salidroside, respectively. Then, ileum tissue of rats were collected and the intestinal damage was assayed by HE staining and Chiu scores. Intestinal permeability indices, including serum D-diamine oxidase (DAO), D-lactic acid (DLA) and endotoxin (END) and secretory immunoglobulin A (sIgA) of intestinal tissue were detected by ELISA. T lymphocyte subsets of intestinal tissue were detected by flow cytometry. Expression of tight junction molecules, including ZO-1, Claudin-3, occluding, were detected by PCR and western blot. Activation of TLR4/NF-κB signaling pathway was detected by Western blot analysis. Results Compared with model group and placebo group, salidro group had the decreased intestinal mucosal injury and low Chiu score, and the level of intestinal permeability indices including serum DAO, DLA and END fell off. CD4⁺ T cell percentage, CD4⁺/CD8⁺ ratio and sIgA level were went up, while CD8⁺ T cell percentage was went down. mRNA and the level of protein expressions of ZO-1, claudin-3 and occludin increased, while activation of TLR4/NF-κB signaling pathway was inhibited. Conclusion Salidroside can alleviate the intestinal barrier injury and improve intestinal mucosal immune status of rats under compound stress of hypoxia and training via inhibiting TLR4/NF-κB signalling pathway.
Animals ; Rats ; Rats, Sprague-Dawley ; NF-kappa B ; Toll-Like Receptor 4/genetics* ; Claudin-3 ; Hypoxia ; Immunoglobulin A, Secretory ; Signal Transduction

PURPOSE: Claudin-4 has been reported to function as a paracellular sodium barrier and is one of the 3 major claudins expressed in lung alveolar epithelial cells. However, the possible role of claudin-4 in bronchial asthma has not yet been fully studied. In this study, we aimed to elucidate the role of claudin-4 in the pathogenesis of bronchial asthma. METHODS: We determined claudin-4 levels in blood from asthmatic patients. Moreover, using mice sensitized and challenged with OVA, as well as sensitized and challenged with saline, we investigated whether claudin-4 is involved in the pathogenesis of bronchial asthma. Der p1 induced the inflammatory cytokines in NHBE cells. RESULTS: We found that claudin-4 in blood from asthmatic patients was increased compared with that from healthy control subjects. Plasma claudin-4 levels were significantly higher in exacerbated patients than in control patients with bronchial asthma. The plasma claudin-4 level was correlated with eosinophils, total IgE, FEV1% pred, and FEV1/FVC. Moreover, lung tissues from the OVA-OVA mice showed significant increases in transcripts and proteins of claudin-4 as well as in TJ breaks and the densities of claudin-4 staining. When claudin-4 was knocked down by transfecting its siRNA, inflammatory cytokine expressions, which were induced by Der p1 treatment, were significantly increased. CONCLUSIONS: These findings thus raise the possibility that regulation of lung epithelial barrier proteins may constitute a therapeutic approach for asthma.
Animals ; Asthma ; Claudin-4 ; Claudins ; Cytokines ; Eosinophils ; Epithelial Cells ; Humans ; Immunoglobulin E ; Inflammation ; Lung ; Mice ; Ovum ; Plasma ; RNA, Small Interfering ; Sodium

BACKGROUND/AIMS: Male predominance has been observed in the erosive reflux disease (ERD), but reverse finding in nonerosive reflux disease (NERD). This suggests sex-specific medicine approach is needed but its mechanism is remained to be elucidated. We aimed to compare clinical characteristics and mRNA expression levels of tight junction-related proteins between male and female gastroesophageal reflux disease (GERD). METHODS: Sixteen healthy controls, 45 ERD, and 14 NERD patients received upper endoscopies and completed questionnaires. Quantitative real-time polymerase chain reactions of occludin (OCLN), zonal occludens (ZO) 1, claudin-1 (CLDN1) and claudin-4 (CLDN4), and neurokinin 1 receptor (NK1R) were performed in the distal esophageal mucosal specimen. These results were analyzed by sex. RESULTS: Female GERD patients were affected more by reflux symptoms than males. The impairment of overall quality of life was more prominent in female patients with reflux symptoms than male patients (5.6±0.2 vs 4.9±0.6, p=0.009). The levels of OCLN mRNA expression were significantly lower in the male ERD group. On the other hand, those of CLDN1, CLDN4, and NK1R except ZO-1 were significantly higher in the male ERD group. CONCLUSIONS: We demonstrated that female ERD/NERD patients were affected more by GERD and male ERD patients showed significant changes of tight junction protein mRNA expression levels.
Claudin-1 ; Claudin-4 ; Female* ; Fluconazole ; Gastroesophageal Reflux* ; Hand ; Humans ; Male* ; Occludin ; Polymerase Chain Reaction ; Quality of Life ; Receptors, Neurokinin-1 ; RNA, Messenger* ; Tight Junction Proteins ; Tight Junctions*

OBJECTIVE: To investigate the expression of claudin 4 (CLDN4) in cervical tissues from patients with different cervical lesions, and to explore the value of combined detection of CLDN4 and high risk human papilloma virus (HR-HPV). METHODS: The cervical tissue specimens of low-grade squamous intraepithelial lesion (LSIL, =30), high-grade squamous intraepithelial lesion (HSIL, =30), squamous cell carcinoma (SCC, =30) as well as chronic cervicitis (control, =30) were collected from the Sir Run Run Shaw Hospital of Zhejiang University during June 2015 and December 2016. The expression of CLDN4 protein in tissue specimens was detected by immunohistochemistry, HR-HPV was detected by real-time quantitative PCR, and the cervical exfoliated cells were examined by thinprep cytologic test (TCT). The ROC curve was applied to analyze the diagnostic value of TCT combined with HR-HPV and CLDN4 combined with HR-HPV tests for HSIL and SCC of the cervix. RESULTS: With the increase of the severity of cervical lesions, the positive rate of CLDN4 expression rose (=0.832, <0.05). Positivity of both HR-HPV infection and CLDN4 expression was found mainly in the HSIL and SCC groups. The areas under curve (AUC) of TCT combined with HR-HPV and CLDN4 combined with HR-HPV tests for diagnosis of HSIL and SCC were 0.683 and 0.633, respectively; the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of TCT combined with HR-HPV test for diagnosis of HSIL and SCC were 100.0%, 36.7%, 61.2%, 100.0% and 46.7% respectively; those of CLDN4 combined with HR-HPV test were 96.7%, 30.0%, 58.0%, 90.0% and 55.0%, respectively. CONCLUSIONS CLDN4 expression may be related to the occurrence and development of cervical carcinoma and precancerous lesions. CLDN4 combined with HR-HPV test may be used for diagnosis of HSIL and SCC of the cervix clinically.
Carcinoma, Squamous Cell ; diagnosis ; virology ; Cervical Intraepithelial Neoplasia ; diagnosis ; virology ; Claudin-4 ; genetics ; metabolism ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Immunochemistry ; Papillomaviridae ; isolation & purification ; Real-Time Polymerase Chain Reaction ; Squamous Intraepithelial Lesions of the Cervix ; virology ; Uterine Cervical Neoplasms ; diagnosis

BACKGROUND/AIMS: Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model. METHODS: The effects of 17β-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions. RESULTS: The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p < 0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-κB, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2. CONCLUSIONS: E2 acts through the estrogen receptor β signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.
Animals ; Azoxymethane ; Blotting, Western ; Claudin-4 ; Colitis* ; Colitis, Ulcerative ; Colon* ; Colonic Neoplasms ; Cytokines ; Enzyme-Linked Immunosorbent Assay ; Eosine Yellowish-(YS) ; Epithelial Cells ; Estradiol ; Estrogens ; Hematoxylin ; Humans ; Inflammation* ; Inflammatory Bowel Diseases ; Male ; Mice* ; Mucin-2 ; Mucin-4 ; Occludin ; Permeability* ; Peroxidase ; Real-Time Polymerase Chain Reaction ; RNA, Messenger ; Sodium ; Tight Junctions

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

BACKGROUND: Excess energy supply induces chronic low-grade inflammation in association with oxidative stress in various tissues including intestinal epithelium. The objective of this study was to investigate the effect of high-fat diet (HFD) on intestinal cell membrane integrity and intestinal tumorigenesis in ApcMin/+ mice. METHODS: Mice were fed with either normal diet (ND) or HFD for 12 weeks. The number of intestinal tumors were counted and biomarkers of endotoxemia, oxidative stress, and inflammation were determined. Changes in intestinal integrity was measured by fluorescein isothiocyanate (FITC)-dextran penetration and membrane gap junction protein expression. RESULTS: HFD group had significantly higher number of tumors compared to ND group (P < 0.05). Blood total antioxidant capacity was lower in HFD group, while colonic 8-hydroxy-2'-deoxyguanosine level, a marker of oxidative damage, was higher in HFD group compared to that of ND group (P < 0.05). The penetration of FITC-dextran was substantially increased in HFD group (P < 0.05) while the expressions of membrane gap junction proteins including zonula occludens-1, claudin-1, and occludin were lower in HFD group (P < 0.05) compared to those in ND group. Serum concentration of lipopolysaccharide (LPS) receptor (CD14) and colonic toll-like receptor 4 (a LPS receptor) mRNA expression were significantly higher in HFD group than in ND group (P < 0.05), suggesting that significant endotoxemia may occur in HFD group due to the increased membrane permeability. Serum interleukin-6 concentration and myeloperoxidase activity were also higher in HFD group compared to those of ND group (P < 0.05). CONCLUSIONS: HFD increases oxidative stress disrupting intestinal gap junction proteins, thereby accelerating membrane permeability endotoxemia, inflammation, and intestinal tumorigenesis.
Animals ; Biomarkers ; Carcinogenesis* ; Cell Membrane* ; Claudin-1 ; Colon ; Colonic Neoplasms ; Connexins ; Diet ; Diet, High-Fat* ; Endotoxemia ; Fluorescein ; Inflammation ; Interleukin-6 ; Intestinal Mucosa ; Membranes ; Mice ; Occludin ; Oxidative Stress ; Permeability ; Peroxidase ; RNA, Messenger ; Toll-Like Receptor 4

OBJECTIVETo understand the junction protein expression of gastric mucosa including occlusal proteins (occludin), closed protein-4 (claudin-4), zonula occluden-1(ZO-1), epithelial cadherin (E-cadherin), and β ring protein (β-catenin) and the clinical significance in children with Helicobacter pylori (Hp) infection.

METHODSeventy patients in whom gastric endoscopy was performed because of nausea, vomiting, abdominal pain, bloating, acid reflux, melena, and other gastrointestinal symptoms were enrolled in this study from Dec. 2010 to Apr. 2013 in our hospital. Informed consent was signed by their parents, and the study was in accordance with the principles of medical ethics. Hp positivity was confirmed if both respiratory urea test (RUT) and Hp were positive by gastric mucosal pathology. Gastric mucosal samples from 70 patients were enrolled in this study, 23 of them were Hp negative, 47 of them were Hp positive (24 cases without peptic ulcer, 23 cases with peptic ulcer). The mRNA levels and protein expression of tight junction protein of gastric mucosa were measured by RT-PCR and Western blot respectively. The location and semi quantitative content of E-cadherin and β-catenin in gastric mucosa were detected by immunohistochemical staining method.

RESULTThe mRNA level of E-cadherin, β-catenin, ZO-1 in the Hp positive group regardless of peptic ulcer was significantly lower than that in the Hp negative group. Hp positive without peptic ulcer group were 0.0008, 0.0040, 0.0014, respectively; Hp positive with peptic ulcer group were 0.0010, 0.0090, 0.0013, respectively; Hp negative group were 0.0137, 0.0423, 0.0198, respectively (F values were 36.956, 39.893, 38.962, respectively, all P<0.05). The expression of claudin-4 mRNA in Hp positive group with peptic ulcer increased significantly, the difference among Hp positive group with peptic ulcer, Hp positive group without peptic ulcer and Hp negative group was statistically significant (0.1438 vs. 0.0926 vs. 0.0789) (F value was 11.964, P<0.05), while the difference of occludin mRNA levels among the three groups was not statistically significant.Immunohistochemistry results showed that the score of E-cadherin, β-catenin positive cell in the Hp positive patients were also significantly lower than that in the Hp negative group (t values were 3.981 and 2.340, all P<0.05, respectively). Western blot results showed that the protein levels of β-catenin in Hp positive group with peptic ulcer were significantly lower than that in Hp negative group, while the protein levels of E-cadherin in Hp positive patients regardless of peptic ulcer were decreased significantly in Hp negative group.

CONCLUSIONOur results revealed that the tight junction protein E-cadherin, β-catenin, ZO-1 expression of gastric mucosa were decreased in children with Hp infection, while claudin-4 expression was increased in Hp positive patients with peptic ulcer, suggesting that damage to gastric epithelial barrier function may be the main pathogenesis of Hp associated gastric diseases in children.

Blotting, Western ; Cadherins ; metabolism ; Child ; Claudin-4 ; metabolism ; Gastric Mucosa ; metabolism ; pathology ; Helicobacter Infections ; metabolism ; Helicobacter pylori ; Humans ; Immunohistochemistry ; Occludin ; metabolism ; Peptic Ulcer ; metabolism ; microbiology ; RNA, Messenger ; Tight Junction Proteins ; metabolism ; Tight Junctions ; metabolism ; Zonula Occludens-1 Protein ; metabolism ; beta Catenin ; metabolism

BACKGROUND: The development of diagnostic techniques and an awareness of health examinations can bring about an early diagnosis of lung cancer. However, appropriate postoperative management and adjuvant chemotherapy remain under debate in postoperative therapeutic strategy. The present study was conducted to assess the clinicopathologic factors that influence recurrence and prognosis after complete resection of lung cancer. METHODS: The present study analyzed 62 patients with lung cancer who underwent complete resection of diagnosed adenocarcinoma between 1994 and 2007. In addition to conventional factors, which include staging factor and histological evaluation, the present study also performed univariate and multivariate analyses to consider claudin, a cell adhesion molecule, as a prognostic factor by immunohistochemical staining. RESULTS: There was no correlation between conventional factors, including lymphatic and vascular invasion, and recurrence. However, there was a significant correlation between high expression of claudin 4 and cancer recurrence. In particular, there was a correlation between high expressions of claudin 1, 4, and 5 and a reduction of disease-free survival. CONCLUSION: Increased expressions of claudin 4 were negative prognostic factors in adenocarcinoma of the lung and thus could be used to identify high-risk patients for adjuvant chemotherapy, even if they had early-stage lung cancer. The present findings collectively suggest that consideration of claudin as a prognostic factor in the active postoperative treatment in patients at high risk will lead to better therapeutic outcomes with fewer side effects.
Adenocarcinoma* ; Cell Adhesion ; Chemotherapy, Adjuvant ; Claudin-1 ; Claudin-4* ; Disease-Free Survival ; Early Diagnosis ; Humans ; Lung Neoplasms ; Lung* ; Multivariate Analysis ; Prognosis ; Recurrence

Tight junction (TJ) is recognized as a second barrier of the skin. Altered expression of TJ proteins in various skin diseases characterized by the abnormal permeability barrier such as psoriasis suggests that TJ could be affected by stratum corneum (SC) barrier status. However, the physiological relationship between SC and TJ barrier remains to be investigated. Therefore, we examined the effect of SC barrier disruption on the expression of TJ proteins, claudin (Cldn)-1 and Cldn-4, and TJ barrier function in hairless mouse skin. We also investigated whether the alterations in epidermal Ca2+ affected TJ proteins expression in vivo. Repeated tape-stripping induced a sequential change of the expression and function of TJ. As early as 15-30 minutes after tape-stripping, downregulation of Cldn-1 and Cldn-4 immunoreactivity and protein level without change in mRNA level was found. This was accompanied by the abnormal leakage of lanthanum. However, by 1 hour Cldn-1 and Cldn-4 immunolocalization recovered along with normalized lanthanum permeation pattern. Moreover, the mRNA and protein levels of Cldn-1 and Cldn-4 were increased by 1 to 6 hours after tape-stripping. Inhibition of calcium loss by immersion of barrier-disrupted skin into a high Ca2+ solution prevented the dislocation of Cldn-1 and Cldn-4. Occlusion of barrier-disrupted skin delayed the restoration of Cldn-1 and Cldn-4. Our results suggest that the alteration of epidermal Ca2+ gradient caused by SC barrier perturbation affects the TJ structure and function and the faster recovery of TJ as compared to the SC barrier may imply the protective homeostatic mechanism of skin barrier.
Animals ; Calcium/*metabolism ; Claudin-1/genetics/*metabolism ; Claudin-4/genetics/*metabolism ; Epidermis/metabolism/*physiology ; Female ; Gene Expression Regulation ; Mice ; Mice, Hairless ; Permeability ; RNA, Messenger/metabolism ; Tight Junctions/metabolism/*physiology