P38 MAP-kinase pathway is involved in the production of CLC-3 in nasal epithelial cells with allergic rhinitis induced by interleukin-4

HDAC inhibitor sodium butyrate prevents allergic rhinitis and alters lncRNA and mRNA expression profiles in the nasal mucosa of mice

Our previous study demonstrated that intranasal administration of histone deacetylase inhibitor sodium butyrate (NaB) exhibits therapeutic effects on a mouse model of allergic rhinitis (AR). However, whether NaB is effective on AR when administered orally and prophylactically, as well as its potential effects on gene expression, remained unknown. The present study aimed to investigate the preventive effect of NaB on AR when added to the diet of newly weaned mice and to evaluate the changes in long non-coding (lnc)RNA and mRNA expression profiles in the nasal mucosa. Mice were randomly divided into three groups as follows: i) Control (C) group, (no treatment); ii) AR group [treated with ovalbumin (OVA)]; and iii) NaB + AR group (treated with OVA and NaB). The NaB + AR group was administered NaB in their feed (30 g/kg chow), whereas the other two groups were fed normal feed between 3 and 6 weeks of age. At 7 weeks of age, OVA administration was initiated to induce AR in the AR and NaB + AR groups. Following model establishment, behavioral assessments, western blotting and gene expression analysis were performed. NaB exhibited a preventive effect in the murine AR model, diminished the increases in histone deacetylase 1 (HDAC1) and HDAC8 expression and increased OVA-induced acetylation of histone H3 at lysine 9. In addition, NaB increased the AR-associated low expression of interleukin 2 (IL-2), interferon γ and IL-17 and decreased the expression of IL-4, IL-5 and transforming growth factor β1. Gene Ontology and pathway analyses revealed the top 10 pathways among the groups. Octamer-binding transcription factor 1, ecotropic viral integration site 1 and paired box 4 were predicted to be target genes of lncRNA (NONMMUT057309). Thus, NaB may exhibit a preventive effect on AR. Additionally, the lncRNA and mRNA expression profiles in the nasal mucosa of mice with AR differed significantly following NaB treatment. These results may provide insights into the pathogenesis of AR and suggest new treatment targets.

MicroRNA‑16 inhibits interleukin‑13‑induced inflammatory cytokine secretion and mucus production in nasal epithelial cells by suppressing the IκB kinase β/nuclear factor‑κB pathway

Chronic inflammation of the nasal mucosal tissue plays important roles in the pathogenesis of allergic rhinitis (AR). Aberrantly expressed microRNAs (miRNAs) have been found to have strong associations with inflammatory reactions in allergic diseases; however, its functional significance and molecular mechanism underlying in AR remains unclear. The aim of the present study was to investigate the biological functions of miRNA and reveal its underlying molecular mechanisms in AR. miRNA microarray was performed to analyze miRNAs expression levels in 3 paired nasal mucosal samples from patients with AR and a control group. Subsequently, human nasal epithelial cells (JME/CF15) were used as an in vitro model to further explore the functions of miRNAs. Microarray data revealed that miR‑16 was one of the miRNAs being most significantly downregulated. Interleukin (IL)‑13 stimulation gradually decreased the levels of miR‑16 in JME/CF15 cells. Moreover, upregulation of miR‑16 inhibited inflammatory cytokines, including granulocyte‑macrophage colony‑stimulating factor (GM‑CSF), eotaxin, IL‑1β, IL‑6 and IL‑10 in IL‑13‑treated JME/CF15 cells. Furthermore, overexpression of miR‑16 significantly decreased the mRNA and protein expression levels of mucin 5AC (MUC5AC). IκB kinase β (IKKβ) was identified as a direct target of miR‑16 and its expression was negatively regulated by miR‑16 at mRNA and protein levels. Notably, forced expression of miR‑16 blocked NF‑κB signaling by decreasing the expression of nuclear p‑p65 and p‑IκB‑α, as well as increasing the expression of IκB‑α in IL‑13‑treated nasal epithelial cells. Moreover, enhanced IKKβ reactivated the NF‑κB pathway that was blocked by miR‑16 mimics and then effectively suppressed the miR‑16‑mediated inhibitory effects on inflammatory response. These findings suggested that miR‑16 suppressed the inflammatory response by inhibiting the activation of IKKβ/NF‑κB signaling pathways.

Interleukin(IL)-4 promotion of CXCL-8 gene transcription is mediated by ERK1/2 pathway in human pulmonary artery endothelial cells

Interleukin-4 is central to allergic pulmonary inflammatory responses, but its contribution to airway neutrophilia remains controversial. The endothelium plays a critical role in regulating leukocyte recruitment and migration during inflammation. However, its response to IL-4 is reported to either increase or decrease the production of neutrophil chemotactic factors. We hypothesized that these conflicting findings may be due to the tissue and the size of the vessels from which endothelial cells have been derived. The expression of CXCL-8 by human primary culture umbilical veins endothelial cells (HUVECs), human pulmonary artery endothelial cells (HPAECs), and human pulmonary microvascular endothelial cells (HPMECs) when stimulated with recombinant human IL-4 (rhIL-4) was studied. The chemoattractant property of the cells' supernatants for neutrophils was evaluated using Boyden chambers. The role of the nuclear factor-κB (NF-κB), and mitogen-activated protein kinases (MAPK) in IL-4-induced HPAECs was studied using Western blotting and electrophoretic mobility shift assay (EMSA). We demonstrated that IL-4 increased the mRNA expression and the protein production of CXCL-8 in HPAECs, but not in HUVECs and HPMECs. The supernatants of HAPECs stimulated by IL-4 significantly promoted neutrophils migration in a dose-dependent manner, and was significantly attenuated by an inhibitor of CXCL-8. We also found that extracellular-regulated protein kinase1/2 (ERK1/2) is activated by IL-4 in HPAECs, but not JUN-N-terminal protein kinase (JNK) or p38 MAPK pathway. Furthermore, NF-κB-DNA binding activity, phosphorylation of IκBα and p65 levels were not affected by rhIL-4 in HAPECs. These findings indicate marked functional differences in the response of micro and macro-ECs to IL-4. ERK1/2, rather than NF-κB, JNK and p38 MAPK signaling, plays a role in IL-4 induced chemokine activation. Our results suggest that inhibition of ERK1/2 may be a possible target for airway neutrophilia in allergic lung diseases.

Overproduction of cyclin D1 is dependent on activated mTORC1 signal in nasopharyngeal carcinoma: implication for therapy

Activated mTOR was implicated to play a role in the carcinogenesis of nasopharyngeal carcinoma (NPC). However, the mechanism of activated mTOR/Complex1(mTORC1) signaling pathway in NPC development has not been well established. In this study, we correlated the expression of mTORC1 signal molecules and Cyclin D1 in NPC. We also investigated the effect of blocking mTORC1 signal with rapamycin and mTOR siRNA on Cyclin D1 expression in CNE-2 cells, as well as cell apoptosis and viability. We found a positive association of mTORC1 signal molecules and Cyclin D1 in NPC. Also, we found blockage mTORC1 inhibited Cyclin D1 expression in CNE-2 cells and enhanced cell apoptosis. Our results suggested that mTORC1 signal pathway might be a potential target for NPC therapy.

Possible role of transforming growth factor beta and interleukin-4 in the up-regulation of CLC-2 and CLC-3 in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) may cover different disease entities, and the pathogenic mechanism remains unclear.

METHODS

The aim of this study was to evaluate the expression of chloride channel protein CLC-2 and CLC-3 in CRS without nasal polyps (CRSsNP) and evaluate the roles of interleukin (IL)-4 and transforming growth factor (TGF) beta in the up-regulation of CLC-2 and CLC-3. We detected expression of CLC-2 and CLC-3 in 17 patients with CRSsNP by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR), and we examined the concentration of TGF-beta, IL-4, IL-5, and interferon (IFN) gamma in ethmoid sinus mucosa by enzyme-linked immunosorbent assay (ELISA).

RESULTS

We found that CLC-2 and CLC-3 is up-regulated in CRSnNP and located in submucosal glands and epithelium of the ethmoid sinus. CLC-2 and CLC-3 mRNA correlated with IL-4 in CRSsNP (r = 0.57 and 0.65; p < 0.05). CLC-2 and CLC-3 mRNA correlated negatively with mucosal TGF-beta in CRSsNP (r = -0.49 and -0.54; p < 0.05).

CONCLUSION

We concluded that CLC-2 and CLC-3 is up-regulated in ethmoid mucosa and may affect the development of CRSsNP. TGF-beta and IL-4 may modulate the expression of CLC-2 and CLC-3 in CRSsNP.

Hypertonic saline solution stimulated CLC-3 production in primary cultured human nasal epithelial cells

OBJECTIVE

To determine the molecular mechanisms of hypertonic saline on nasal disorders.

METHODS

Primary human nasal epithelial cells (HNECs) were treated with 0.9 and 3% saline for 12h. CLC-3 was detected in HNECs by immunohistochemistry, reverse transcriptase-polymerase chain reaction (RT-PCR) and western blotting.

RESULTS

Positive expression of CLC-3 was detected in HNECs in all subjects by immunohistochemistry. The relative density of CLC-3 mRNA was 0.22+/-0.09 and 0.12+/-0.05 in HNECs treated with 3 and 0.9% saline, respectively. The effect of 3% saline on the expression of CLC-3 in HNECs was observed in a time-dependent manner.

CONCLUSIONS

Hypertonic saline decreases the nasal edema and influences the mucocilliary function through the fluid secretion in vitro and may be associated with the upregulation of CLC-3.

Inverse association between T-cell immunoglobulin and mucin domain-1 and T-bet in a mouse model of allergic rhinitis

BACKGROUND

It has been suggested that human hepatitis A virus cellular receptor, also known as T-cell immunoglobulin and mucin domain-1 (TIM-1), plays an important role in the development of allergic diseases on the basis of epidemiologic data, but the molecular mechanism has been unclear. In a murine model of ovalbumin (OVA)-sensitized allergic rhinitis (AR), we examined the expression of TIM-1 and its correlation with T helper1-associated transcription factor, T-bet, as a potential mediator of T-cell immunoglobulin expression.

METHODS

Mice were challenged intranasally with OVA to elicit AR. The expression of TIM-1 in nasal tissues was examined by real-time reverse-transcription polymerase chain reaction (RT-PCR), and the surface expression of TIM-1 in peripheral blood mononuclear cells was evaluated by means of flow cytometry. In addition, the expression of TIM-1 as well as T-bet in splenic lymphocytes was examined by Western blotting.

RESULTS

TIM-1 mRNA was increased significantly in nasal tissues (P < .05) as seen by real-time RT-PCR. Flow cytometry indicated a differential TIM-1 expression of 135.5 +/- 34.2 in the AR group versus 51.1 +/- 10.9 in the control group (P < .05). The mean values of normalized TIM-1 were 0.43 +/- 0.18 and 0.21 +/- 0.10 in AR and control groups, respectively, whereas the mean values of normalized T-bet were 0.22 +/- 0.13 and 0.67 +/- 0.17 in the AR and control groups, respectively. There was a significant difference in the production of TIM-1 as well as T-bet in AR mice versus control mice (P < .05). The increased production of TIM-1 correlated significantly with the decreased T-bet in spleen tissue of AR mice (r = -0.52, P < .05).

CONCLUSION

Our experimental model recapitulates an increase in lymphocyte TIM-1 expression seen in AR both locally and systemically. Our results also demonstrate an inverse relationship between lymphocyte TIM-1 and T-bet expression, suggesting a possible mechanism that TIM-1 influences the development of AR.