The therapeutic effect of cimifugin on atopic dermatitis in mice and its mechanism / 中国药理学通报

Aim To investigate the effects of cimifugin on mouse atopic dermatitis (AD) induced by fluorescein isothiocyanate (FITC) and further explore the mechanism of its action. Methods ICR mice were randomly divided into blank group, model group, positive group (dexamethasone),low dose group,high dose group and administration group of cimifugin. FITC solution was applied to the shaved abdomen of mice in the sensitization stage, and 0.6 % FITC solution was applied to attack the ears of mice in the stimulation stage. The administration groups were given medicine for seven consecutive days. The effects of cimifugin on body weight, thymus index and spleen index of mice were detected. Ear inflammatory cell infiltration was observed by HE staining. The ear swelling of mice was measured, and Th2 cytokines IL-5,IL-13 and the key promoter of allergy IL-33 were detected by ELISA. The epithelial barrier structural proteins, filaggrin, claudinl,occludin and E-cadherin,were detected by immunohistochemistry and Western blot. Results Compared with the blank group, the model group showed significant AD symptoms. Compared with the model group, cimifugin transdermal administration group significantly reduced ear inflammatory cell infiltration,ear swelling, IL-5,IL-13 and IL-33, and significantly increased the expression of filaggrin and occludin. Conclusions Transdermal administration of cimifugin could significantly inhibit AD in mice, and its mechanism involves repairing epithelial barrier function, restoring filaggrin and occludin, inhibiting allergy promoting factor IL-33, and finally inhibiting AD inflammation.

Advances in the study of natural small molecules to protect the intestinal epithelial tight junction barrier in inflammatory bowel disease / 中国药理学通报

Inflammatory bowel disease (IBD), as an idiopathic inflammatory disease of the intestinal tract, consisting mainly of Crohns disease and ulcerative colitis, which can involve the rectum, colon and ileum, and whose pathogenesis is still not fully understood. The initiation of intestinal inflammation associated with IBD and its chronieity begins with increased intestinal permeability caused by intestinal epithelial barrier disruption. The anti-permeability of the intestinal epithelial barrier is maintained by tight junction in the apical region of the intestinal epithelial cells, and disruption of the tight junction structure is closely associated with intestinal epithelial barrier damage and the development of IBD. Therefore, it is significant to find drugs for the prevention and treatment of IBD using tight junctions as regulatory targets. In recent years, many small molecules of natural product origin have been reported to improve the effects of IBD. In particular, we review the compounds that have the function of repairing intestinal epithelial barrier and protecting tight junction structure, in order to provide research ideas for the design and development of new drugs for the prevention and treatment of IBD.

Biomarkers of gastrointestinal dysfunction in children / 中国小儿急救医学

Due to incomplete function of gastrointestinal barrier, children are more likely to develop gastrointestinal dysfunction.The clinical application of related biomarkers helps early diagnosis and treatment of gastrointestinal dysfunction in children.By sorting out the studies in recent years, we explored the relationship between inflammatory indicators, intestinal epithelial barrier damage biomarkers, immunological biomarkers, gut microbiome and gastrointestinal dysfunction, and summarized the main problems and solutions faced in the research, which may help the screening, identification and clinical application of relevant biomarkers in subsequent research.

Yes-associated protein ameliorates tumor necrosis factor-α-induced epithelial barrier dysfunction by affecting the F-actin / 中国小儿急救医学

Objective:To investigate the protective role of Yes-associated protein(YAP)in intestinal epithelial barrier injury.Methods:The intestinal epithelial barrier model was established by culturing human colorectal adenocarcinoma cell line Caco-2 cells, which were divided into four groups: control group, Caco-2 monolayers did not receive any treatment; recombinant human tumor necrosis factor-α(rhTNF-α)group, 100 μg/L of rhTNF-α was added to Caco-2 monolayers; vector+ rhTNF-α group, Caco-2 monolayers were first added with control plasmid pcDNA3.1-vector, and 100 μg/L rhTNF-α was added 24 hours later; YAP+ rhTNF-α group, Caco-2 cells with barrier construction were first added with pcDNA3.1-YAP, and 100 μg/L rhTNF-α was added 24 hours later.Realtime-PCR and Western blot were used to evaluate YAP mRNA and protein expression level.Epithelial permeability was assayed by trans-epithelial electrical resistance(TEER)and fluorescein isothiocyanate-dextran 40(FD-40 flu). Cellular distribution of F-actin was assayed by immunofluorescence staining.Results:Compared with control group[(607.3±29.3)Ω·cm 2], TEER of rhTNF-α group[(265.3±32.7)Ω·cm 2] decreased, while TEER of YAP+ rhTNF-α group[(387.0±18.7)Ω·cm 2]increased compared with rhTNF-α group, the differences were statistically significant( P<0.001). The FD-40 flux of rhTNF-α(22.7%±0.5%) group was higher than that of the control group(6.3%±0.9%), while the FD-40 flux of Yap + rhTNF-α group(12.2%±0.8%) was lower than that of rhTNF-α group, the differences were statistically significant( P<0.001). Immunofluorescence staining showed that compared with the control group, the cytoskeletal F-actin fiber dense spot decreased in rhTNF-α group, and some cells showed obvious trans-cellular stress fiber structure, while the peripheral actin band was clear in YAP+ rhTNF-α group, and the intracellular stress fiber decreased.YAP+ TNF-α group appeared as a clear, peripheral actin ribbon with a decrease in cytoplasmic stress fibres. Conclusion:YAP overexpression significantly inhibits TNF-α induced decline of TEER, and increases of FD-40 flux and F-actin rearrangement of Caco-2.YAP could ameliorate TNF-α induced intestinal epithelial barrier injury by regulating cytoskeleton F-actin.

Transcriptome analysis of primary human oral keratinocytes stimulated with Prevotella melaninogenica / 口腔疾病防治

Objective@# To investigate the transcriptomic changes in primary human oral keratinocytes (pHOKs) after coculture with Prevotella melaninogenica (P.m) and to verify the changes in human oral keratinocyte (HOK) cell lines.@*Methods@# pHOK was isolated and cocultured with P.m for 0, 4 and 24 h. Total RNA was extracted, a gene library was constructed, transcriptional sequencing was performed, differentially expressed genes (DEGs) were analyzed, gene ontology (GO) pathway analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed, and the validation of DEGs was performed by qRT-PCR and Western Blot in the HOK and P.m coculture cell model. @*Results @#1 788 DEGs were detected between the 4 h group and control group, including upregulated DEGs such as lymphocyte cytosolic protein 1(LCP1), keratin 7 (KRT7) and Cilia and flagella associated protein 251(CFAP251) and downregulated DEGs such as FERM, ARH/RhoGEF and Pleckstrin domain protein 1 (FARP1), WW domain containing transcription regulator 1(WWTR1) and Discoidin, CUB and LCCL domain-containing protein 2 (DCBLD2). 1 832 DEGs were detected between the 24 h group and control group, including upregulated DEGs such as LCP1, complement C1s(C1S), kynureninase (KYNU) and downregulated DEGs such as phosphoserine aminotransferase 1 (PSAT1), FARP1 and FKBP prolyl isomerase 10 (FKBP10). There were 1 090 common differentially expressed genes (cDEGs) in the 4 h and 24 h groups, including LCP1, KYNU and long intergenic nonprotein coding RNA 958 (LINC00958). The GO pathways were mainly enriched in response to lipopolysaccharide and the molecules of bacterial origin and apical part of the cell. KEGG pathway analysis revealed enrichment in the interleukin-17 (IL-17) signaling pathway, tumor necrosis factor (TNF) signaling pathway, Toll-like receptor (TLR) pathway, etc. We verified the expression of a cDEG, Myosin1B (MYO1B), and qRT-PCR and Western Blot analysis showed that MYO1B expression was significantly upregulated between the control group and the P.m cocultured group (P<0.001), and its expression followed a time-dependent and concentration-dependent manner. @*Conclusion@#P.m played an important role in the transcriptome of oral keratinocytes.

Targeting PDE4 as a promising therapeutic strategy in chronic ulcerative colitis through modulating mucosal homeostasis

Phosphodiesterase-4 (PDE4) functions as a catalyzing enzyme targeting hydrolyzation of intracellular cyclic adenosine monophosphate (cAMP) and inhibition of PDE4 has been proven to be a competitive strategy for dermatological and pulmonary inflammation. However, the pathological role of PDE4 and the therapeutic feasibility of PDE4 inhibitors in chronic ulcerative colitis (UC) are less clearly understood. This study introduced apremilast, a breakthrough in discovery of PDE4 inhibitors, to explore the therapeutic capacity in dextran sulfate sodium (DSS)-induced experimental murine chronic UC. In the inflamed tissues, overexpression of PDE4 isoforms and defective cAMP-mediating pathway were firstly identified in chronic UC patients. Therapeutically, inhibition of PDE4 by apremilast modulated cAMP-predominant protein kinase A (PKA)-cAMP-response element binding protein (CREB) signaling and ameliorated the clinical symptoms of chronic UC, as evidenced by improvements on mucosal ulcerations, tissue fibrosis, and inflammatory infiltrations. Consequently, apremilast maintained a normal intestinal physical and chemical barrier function and rebuilt the mucosal homeostasis by interfering with the cross-talk between human epithelial cells and immune cells. Furthermore, we found that apremilast could remap the landscape of gut microbiota and exert regulatory effects on antimicrobial responses and the function of mucus in the gut microenvironment. Taken together, the present study revealed that intervene of PDE4 provided an infusive therapeutic strategy for patients with chronic and relapsing UC.

Effects of arctiin relieving inflammatory injury of human nasopharyngeal epithelial cells induced by lipopolysac- charide / 中国药房

OBJECTIVE To investigate the effect of arctiin （ARC）relieving lipopolysaccharide （LPS）induced inflammatory injury of human nasopharyngeal epithelial cells NP- 69. METHODS The effects of 24 h treatment of 0.000 1，0.001，0.01，0.1， 1.0，10 μmol/L ARC on the proliferation of NP-69 were determined by MTS method. After 0.01，0.1，and 1.0 μmol/L ARC was applied to NP- 69 for 24 h and NP- 69 was pre-treated with 0.01，0.1 and 1.0 μmol/L ARC for 24 h，and then stimulated with 1.0 μg/mL LPS for 24 h，scratch tests were used to detect cell migration in both experiments. LPS stimulated NP- 69 to establish an inflammation injury model. The levels of nitric oxide （NO），tumor necrosis factor α（TNF-α）interleukin-6（IL-6），and IL- 1β in cell supernatants were detected ，and mRNA and protein expression of zonula oecludens protein 1（ZO-1），β-defensin 3（BD3）， Janus kinase 1 （JAK1），signal transducer and activator of transcription 3 （STAT3） in cell supernatant were also detected. RESULTS Compared with normal group ，0.000 1，0.001，0.01，0.1，1.0，10 μmol/L ARC had no effect on the proliferation of NP-69 after 24 h treatment （P＞0.05）. ARC （0.1，1.0 μmol/L）could significantly promote the rate of cell migration （P＜0.05）. For the inflammatory injure of NP- 69 cells stimulated by LPS ，ARC（1.0 μmol/L）could significantly reduce the release of NO ， TNF-α and IL-6（P＜0.05），significantly increased mRNA and protein expression of ZO- 1 and BD 3 but decreased mRNA and protein expression of STAT 3（P＜0.01 or P＜0.05）. CONCLUSIONS ARC has the effect of reducing the inflammatory injury of NP-69 cells induced by LPS ，promoting the physical and immune defense ability of the nasal mucosa epithelial barrierunder inflammatory environment. The mechanism of action may be related to inhibiting IL- 6/JAK1/STAT3 signaling pathway.

Relationship between airway epithelial barrier dysfunction and allergic asthma / 国际儿科学杂志

Airway epithelial barrier dysfunction has been observed in allergic asthma patients.Inhaled allergens have shown a disruptive effect on the airway epithelial barrier.Airway barrier related genetic variation and epigenetics are also involved in the airway epithelial barrier dysfunction.A lot of studies believe that airway epithelial barrier dysfunction underlie the development of asthma.The study of the relationship between allergic asthma and airway epithelial barrier function will be helpful to understand the pathogenesis of allergic asthma and provide new ideas for the treatment of allergic asthma.

Tojapride Reverses Esophageal Epithelial Inflammatory Responses on Reflux Esophagitis Model Rats / 中国结合医学杂志

OBJECTIVE@#To investigate the mechanism of Tojapride, a Chinese herbal formula extract, on strengthening the barrier function of esophageal epithelium in rats with reflux esophagitis (RE).@*METHODS@#Ten out of 85 SD rats were randomly selected as the sham group (n10), and 75 rats were developed a reflux esophagitis model (RE) by the esophageal and duodenal side-to-side anastomosis. Fifty successful modeling rats were divided into different medicated groups through a random number table including the model, low-, medium-, and high-dose of Tojapride as well as omeprazole groups (n10). Three doses of Tojapride [5.73, 11.46, 22.92 g/(kg•d)] and omeprazole [4.17 mg/(kg•d)] were administrated intragastrically twice daily for 3 weeks. And the rats in the sham and model groups were administered 10 mL/kg distilled water. Gastric fluid was collected and the supernatant was kept to measure for volume, pH value and acidity. Esophageal tissues were isolated to monitor the morphological changes through hematoxylin-eosin (HE) staining, and esophageal epithelial ultrastructure was observed by transmission electron microscopy. The expressions of nuclear factor kappa-light-chain-enhancer of activated B cells p65 (NF-KBp65), κB kinase beta (IKKß), occludin, and zonula occludens-1 (ZO-1) in the esophageal tissues were measured by immunohistochemistry and Western blot, respectively.@*RESULTS@#The gastric pH value in the model group was significantly lower than the sham group (P<0.05). Compared with the model group, gastric pH value in the omeprazole and medium-dose of Tojapride groups were significantly higher (P<0.05). A large area of ulceration was found on the esophageal mucosa from the model rats, while varying degrees of congestion and partially visible erosion was observed in the remaining groups. Remarkable increase in cell gap width and decrease in desmosome count was seen in RE rats and the effect was reversed by Tojapride treatment. Compared with the sham group, the IKKß levels were significantly higher in the model group (P<0.05). However, the IKKß levels were down-regulated after treatment by all doses of Tojapride (P<0.01 or P<0.05). The occluding and ZO-1 levels decreased in the model group compared with the sham group (Ps0.01 or Ps0.05), while both indices were significantly up-regulated in the Tojapride-treated groups (P<0.01 or P<0.05).@*CONCLUSIONS@#Tojapride could improve the pathological conditions of esophageal epithelium in RE rats. The underlying mechanisms may involve in down-regulating the IKKß expression and elevating ZO-1 and occludin expression, thereby alleviating the inflammation of the esophagus and strengthening the barrier function of the esophageal epithelium.

Gracilaria fisheri oligosaccharides ameliorate inflammation and colonic epithelial barrier dysfunction in mice with acetic acid-induced colitis

Objective: To investigate the effect of Gracilaria fisheri oligosaccharides (GFO) on inflammation and colonic epithelial barrier dysfunction in colitis mice. Methods: The animals were treated by oral gavage with distilled water, 1 000 mg/kg inulin, 100, 500, or 1 000 mg/kg GFO for 14 d, or treated with 50 mg/kg mesalamine for 5 d after colitis induction (on day 10). Histopathology, inflammatory cytokines, colonic permeability, and tight junction proteins were investigated by hematoxylin and eosin staining, immunohistochemical staining, Ussing chamber technique, and Western blotting assays, respectively. Results: GFO ameliorated histological damage in colitis mice when compared to untreated colitis mice. Treatments with 100, 500, and 1 000 mg/kg GFO reduced TNF-α expression, while IL-1β was significantly reduced in colitis mice treated with 500 and 1 000 mg/kg. Compared to untreated colitis mice, GFO increased transepithelial electrical resistance, reduced fluorescein isothiocyanate-dextran paracellular flux, and modulated tight junction proteins (occludin and claudin 2) in colitis mice. Conclusions: GFO has anti-inflammatory activity and could modulate colonic epithelial barrier dysfunction in acetic acid-induced colitis mice. Furthermore, GFO could modulate the expression of tight junction proteins that play important roles in colonic barrier function.

Primary Nasal Epithelial Cells From Allergic and Non-allergic Individuals Show Comparable Barrier Function

Previous reports suggested that ex vivo cultured primary nasal epithelial cells from allergic patients differ from those from non-allergic individuals by genuinely reduced barrier function. By contrast, we found that primary nasal epithelial cells from allergic and non-allergic individuals showed comparable barrier function and secretion of cytokines.

Dermatitis atópica: Pitiriasis alba. A propósito de un caso / Atopic Dermatitis: Pityriasis Alba. A clinical case

RESUMEN La Pitiriasis alba es una enfermedad cutánea inespecífica de etiología desconocida, caracterizada por máculas hipocrómicas, redondeadas u ovaladas poco delimitadas y cubiertas con escamas finas que ocurren usualmente en la región facial de los niños. Fue descrita por Gilbert en 1860 y Fox en 1923, pero fue O'Farrell en 1956 quien propuso el nombre de Pitiriasis alba. La condición dermatológica con la que suele asociarse es la dermatitis atópica. La presencia de Pitiriasis alba fue definida como uno de los criterios menores para el diagnóstico de Dermatitis atópica, según Hanifin y Rajka en 1980. Sin embargo, también se presenta en 20-40% de los niños atópicos, sin evidencia de Dermatitis atópica, así como en individuos no atópicos. La disfunción de la barrera epitelial causada por mutaciones del gen de la filagrina, proteína estructural epidérmica, que forma parte del factor humectante natural, se considera un factor de riesgo emergente para la Dermatitis atópica severa de comienzo precoz. Se presenta un caso de Pitiriasis albaen el que fue necesaria terapia combinada tópica y vía oral, con evolución satisfactoria en 8 semanas de tratamiento.

SUMMARY Pityriasis Alba is a non-specific skin disease of unknown etiology characterized by hypochromic macules, rounded or oval, poorly defined and covered with fine scales that usually occur in the facial region of children. It was described by Gilbert in 1860 and Fox in 1923, but it was O'Farrell in 1956 who proposed the name Pityriasis alba. The dermatological condition with which it is usually associated is Atopic dermatitis. The presence of Pityriasis alba was defined as one of the minor criteria for the diagnosis of Atopic dermatitis, according to Hanifin and Rajka in 1980. However, it also occurs in 20-40% of atopic children, without evidence of Atopic dermatitis, as well as in non-atopic individuals. Epithelial barrier dysfunction caused by mutations of the filaggrin gene, epidermal structural protein, which is part of the natural humectant factor, is considered an emerging risk factor for severe early onset Atopic dermatitis. We present a case of Pityriasis alba where combined topical and systemic therapy was necessary with satisfactory evolution in 8 weeks of treatment.

Effect of tumor necrosis factor-α on the expression of tight junction proteins ZO-1 and Claudin-4 in rat alveolar epithelial cells / 中华急诊医学杂志

Objective To investigate the effect of TNF-α on the expressions of tight junction protein ZO-1 and Claudin-4 in rat alveolar epithelial typeⅡ cells (AEC-Ⅱ).Methods Rat AEC-Ⅱ cells were culturedin vitro and divided into the control group, and TNF-α 24 h, 48 h, 72 h groups. The control group was cultured with DME F12 medium containing fetal bovine serum, and the TNF-α groups were intervened by TNF-α with a concentration of 10 ng/mL for 24 h, 48 h, and 72 h, respectively. After co-culture, the transmission electron microscopy was used to identify and observe the ultrastructural changes of rat AEC-Ⅱ cells. The cell inhibition rate was determined by MTT assay, and the cell apoptosis rate was measured by flow cytometry. The expression and distribution of tight junction protein ZO-1 and Claudin-4 in each group were observed by immunofluorescence method. The transcriptional levels of ZO-1 and Claudin-4 were detected by real-time fluorescent quantitative PCR. The expressions of ZO-1 and Claudin-4 were detected by Western blot. One-way analysis of variance (ANOVA) was used for comparisons among groups and SNK-q test was used for pairwise comparisons between groups. The non-parametric test of rank transformation was used when homogeneity of variance were not met. The value ofP<0.05 was considered significantly different.Results Transmission electron microscopy showed that the AEC-Ⅱ cells in the control group obtained characteristic lamellar bodies of different sizes. The lamellar bodies in each TNF-α group were gradually emptied and apoptotic cells were observed under the visual field. The cell inhibition rate and early apoptosis rate of each TNF-α group were significantly higher than those of the control group (allP<0.05). Confocal microscopy showed that ZO-1 was linearly distributed along the cell membrane, and Claudin-4 was scattered along the cell membrane. In the TNF-α groups, the fluorescence intensity of ZO-1 was weakened and the continuity was broken as well as the linear structure. The fluorescence intensity and density of Claudin-4 were decreased in the TNF-α groups. Besides, the transcription and expression of ZO-1 in the TNF-α 24 h group were lower than those in the control group, but there was no significant difference (P>0.05). However, the mRNA level of ZO-1 in the TNF-α 48 h group (0.28±0.06) and 72 h group (0.13±0.07) were significantly lower than those in the control group. And their protein levels of TNF-α 48 h group (0.44±0.09) and of TNF-α 72 h group (0.2±0.01) were lower than that of the control group (0.69±0.12). Compared with the control group, the transcription level (24 h: 0.16±0.03; 48 h: 0.04±0.01; 72 h: 0.01±0.00vs 1.00±0.00) and expression (24 h: 0.49±0.08; 48 h: 0.34±0.05; 72 h: 0.04±0.01vs 0.96±0.13) of Claudin-4 in each TNF-α group were significantly decreased, and showed a decreasing trend with time (allP<0.05).Conclusions TNF-α can damage the pulmonary epithelial barrier by damaging alveolar epithelial typeⅡ cells and down-regulating the expression and distribution of ZO-1 and Claudin-4.

Advances in the study of microRNA-7 involved in the injury and repair of intestinal epithelial barrier via EGFR / 国际儿科学杂志

MicroRNAs (miRNAs) are non-coding single-stranded small RNAs composed of 19 ～25 nucleotides involved in various life processes such as cell proliferation,differentiation,apoptosis,signal transduction and immune regulation at the post-transcriptional level.So it has become one of the research hotspots in recent years.Among them,MiR-7 is considered to be an important regulator of epithelial cell damage and repair.As the largest epithelium of the human body,the intestinal macosal epithelium is the link between the human body and the outside world,and plays an important role in the homeostasis of the internal environment.Numerous studies have shown that MiR-7 plays an irreplaceable role in intestinal epithelial barrier damage and repair through the epidermal growth factor receptor (EGFR)-related signal pathway.This paper reviews the research progress.

Effect of tumor necrosis factor-α on the expression of tight junction proteins ZO-1 and Claudin-4 in rat alveolar epithelial cells / 中华急诊医学杂志

Objective@#To investigate the effect of TNF-α on the expressions of tight junction protein ZO-1 and Claudin-4 in rat alveolar epithelial typeⅡ cells (AEC-Ⅱ).@*Methods@#Rat AEC-Ⅱ cells were cultured in vitro and divided into the control group, and TNF-α 24 h, 48 h, 72 h groups. The control group was cultured with DME F12 medium containing fetal bovine serum, and the TNF-α groups were intervened by TNF-α with a concentration of 10 ng/mL for 24 h, 48 h, and 72 h, respectively. After co-culture, the transmission electron microscopy was used to identify and observe the ultrastructural changes of rat AEC-Ⅱ cells. The cell inhibition rate was determined by MTT assay, and the cell apoptosis rate was measured by flow cytometry. The expression and distribution of tight junction protein ZO-1 and Claudin-4 in each group were observed by immunofluorescence method. The transcriptional levels of ZO-1 and Claudin-4 were detected by real-time fluorescent quantitative PCR. The expressions of ZO-1 and Claudin-4 were detected by Western blot. One-way analysis of variance (ANOVA) was used for comparisons among groups and SNK-q test was used for pairwise comparisons between groups. The non-parametric test of rank transformation was used when homogeneity of variance were not met. The value of P<0.05 was considered significantly different.@*Results@#Transmission electron microscopy showed that the AEC-Ⅱ cells in the control group obtained characteristic lamellar bodies of different sizes. The lamellar bodies in each TNF-α group were gradually emptied and apoptotic cells were observed under the visual field. The cell inhibition rate and early apoptosis rate of each TNF-α group were significantly higher than those of the control group (all P<0.05). Confocal microscopy showed that ZO-1 was linearly distributed along the cell membrane, and Claudin-4 was scattered along the cell membrane. In the TNF-α groups, the fluorescence intensity of ZO-1 was weakened and the continuity was broken as well as the linear structure. The fluorescence intensity and density of Claudin-4 were decreased in the TNF-α groups. Besides, the transcription and expression of ZO-1 in the TNF-α 24 h group were lower than those in the control group, but there was no significant difference (P>0.05). However, the mRNA level of ZO-1 in the TNF-α 48 h group (0.28±0.06) and 72 h group (0.13±0.07) were significantly lower than those in the control group. And their protein levels of TNF-α 48 h group (0.44±0.09) and of TNF-α 72 h group (0.2±0.01) were lower than that of the control group (0.69±0.12). Compared with the control group, the transcription level (24 h: 0.16±0.03; 48 h: 0.04±0.01; 72 h: 0.01±0.00 vs 1.00±0.00) and expression (24 h: 0.49±0.08; 48 h: 0.34±0.05; 72 h: 0.04±0.01 vs 0.96±0.13) of Claudin-4 in each TNF-α group were significantly decreased, and showed a decreasing trend with time (all P<0.05).@*Conclusions@#TNF-α can damage the pulmonary epithelial barrier by damaging alveolar epithelial typeⅡ cells and down-regulating the expression and distribution of ZO-1 and Claudin-4.

Alteration in Claudin-4 Contributes to Airway Inflammation and Responsiveness in Asthma

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.

Updates on microRNA in intestinal epithelial barrier / 国际儿科学杂志

MicroRNAs are a group of large and highly conserved non-coding small stranded RNAs that regulate the gene expression by translational inhibition or mediated degradation of target proteins at post-transcriptional levels,which plays an important role in many biological processes,including cell apoptosis,immune response,tumorigenesis and nutritional metabolism.The intestinal epithelial barrier is the first defense to maintain the general physiological phenomenon,and its integrity is a critical factor of the maintenance of intestinal mucosal barrier function and intestinal homeostasis.This article reviews the biological function of miRNAsand their post-transcriptional regulation of the formation of intestinal epithelial barrier.

Effect of gut microbiota changes on the intestinal mucosal barrier function in heatstroke / 解放军医学杂志

Heatstroke impairs the intestinal mucosal barrier function,leading to bacteremia,endotoxemia and multiple organ dysfunction.Therefore,protecting intestinal barrier function is critical in the prevention and treatment of heatstroke.Gut microbiota has an important impact on intestinal mechanical,biological and immune barrier.Intestinal dysbacteriosis damages intestinal b,arrier,which leads to enterogenous bacteria and endotoxin from the intestinal lumen entering into the circulation and thus causes systemic inflammatory response syndrome.This process can trigger heatstroke and promote its development and progression.However,probiotics can reduce endotoximia and inflammatory cytokines by improving the intestinal barrier function.Therefore,according to the effect of gut microbiota on the relevant aspects of intestinal mucosal barrier,searching for target probiotics and intervention may be an effective strategy for the prevention and treatment of heatstroke against intestinal barrier damage.

Paeoniflorin alleviates TNF-α induced intestinal barrier dysfunction by inhibition of MLCK / 中国药理学通报

Aim To investigate the protective effect of paeoniflorin on TNF-α induced intestinal epithelial barrier dysfunction and its mechanisms.Methods The Caco-2 cells were cultured and the MTF assay was used to determine the effects of the paeoniflorin on Caco-2 cell activity.The Caco-2 cell intestinal epithelial barrier dysfunciton model was established through incubation of cells with TNF-α.The effects of paeoniflorin on intestinal epithelial barrier dysfunciton were studied.Results The transmembrane resistance in Caco-2 epithelial barrier was significantly reduced by TNF-α incubation;MLCK significantly increased,while tight junction protein occludin and ZO-1 significantly decreased by TNF-α.These changes were significantly reversed by paeoniflorin,which reduced MLCK expression and enhanced expression of occludin and ZO-1.The protective effects against epithelial barrier dysfunction could be abrogated by small interfering RNA(siRNA) of MLCK.Conclusions Paeoniflorin alleviates the epithelial barrier dysfunction induced by TNF-αthrough down-regulation of MLCK and enhancement of tight junction protein occludin and ZO-1.This study supplies a potential candidate drug for the clinical treatment of inflammatory bowel diseases.

Effect of protein tyrosine kinase 6 on human airway epithelial barrier dsyfunction induced by TNF-α / 中国免疫学杂志

Objective:To investigate the effect of protein tyrosine kinase 6(PTK6) on TNF-α induced human airway epithelial barrier dysfunction and mechamism.Methods: After cultivating 16HBE cells in vitro,the recombined PTK6 and PTK6 siRNA was respectively transfected into the cells,with empty vector and scramble siRNA as control.The cells were incubated with exogenous TNF-α.Cell viability was detected by MTT assay.Cells TER and permeability were detected.ZO-1 and Occludin mRNA were analyzed by RT-PCR.PTK6,ZO-1,Occludin,p-ERK1/2,p-JNK1/2 and p-p38MAPK protein were assayed by Western blot.Results: TNF-α remarkably decreased ZO-1 and Occludin mRNA and protein and TER;increased cells permeability,as well as p-ERK1/2,p-JNK1/2 and p-p38 protein(P<0.05).Upregulation of PTK6 further decreased ZO-1 and Occludin mRNA and protein and TER,enhanced cells permeability and p-JNK1/2 and p-p38 protein(P<0.05),and downregulated PTK6 ,the changes of these indices were opposite(P<0.05).Whereas upregulation or downregulation of PTK6 had no effect on p-ERK1/2.Conclusion: Downregulation of PTK6 inhibits the phosphorylation of JNK1/2 and p38MAPK,thus improving TNF-α-induced human airway epithelial barrier dysfunction.