ABSTRACT
Abstract Introduction: High mobility group box 1 protein participates in the pathogenesis of allergic rhinitis. Activation of the inflammasome can mediate the release of high mobility group box 1. The role of the absent in melanoma 2 inflammasome in allergic rhinitis remains unclear. Objective: This study aimed to investigate the function of absent in melanoma 2 inflammasome in murine allergic rhinitis and the interaction between high mobility group box 1 and the absent in melanoma 2 inflammasome. Methods: A murine allergic rhinitis model was established using twenty Balb/c mice. Expression of the components of the absent in melanoma 2 inflammasome: absent in melanoma 2, apoptosis-associated speck-like protein containing a CARD (Asc), caspase-1 p20, and additional nod-like receptor family pyrin domain containing 3 (Nlrp3) were detected by western blotting during allergic rhinitis. Alterations of absent in melanoma 2, caspase-1, and high mobility group box 1 after ovalbumin challenge were demonstrated by immunohistochemistry. TdT-mediated dUTP Nick end labeling, TUNEL assay, and cleavage of caspase-3 and PARP-1 were used for the observation of pyroptosis. Results: Eosinophilia and goblet cell infiltration were observed in the nasal mucosa of mice in the allergic rhinitis group. Absent in melanoma 2, Asc, and caspase-1 p20 increased after ovalbumin exposure while Nlrp3 did not. High mobility group box 1 was released in the nasal mucosa of allergic rhinitis mice. TUNEL-positive cells increased in the epithelium and laminae propria, whereas cleavage of caspase-3 and PARP-1 was not observed. Conclusions: The absent in melanoma 2 inflammasome was activated and pyroptosis may occur in the nasal mucosa after ovalbumin treatment. These may contribute to the translocation of high mobility group box 1 and the development of allergic rhinitis.
Resumo Introdução: A proteína do grupo Box-1 de alta mobilidade participa da patogênese da rinite alérgica. A ativação do inflamassoma pode mediar a liberação de proteína do grupo Box-1 de alta mobilidade. O papel do inflamassoma ausente no melanoma 2 na rinite alérgica permanece incerto. Objetivo: Investigar a função do inflamassoma ausente no melanoma 2 em um modelo murino de rinite alérgica e a interação entre a proteína do grupo Box-1 de alta mobilidade e o inflamassoma ausente no melanoma 2. Método: Um modelo murino de rinite alérgica foi estabelecido com 20 camundongos Balb/c. A expressão dos componentes do inflamassoma ausente no melanoma 2, da proteína speck-like associada à apoptose com CARD (Asc), da caspase-1 p20 e do domínio de pirina da família NLR adicional com 3 (Nlrp3) foi detectada por western blotting durante a rinite alérgica. Alterações de inflamassoma ausente no melanoma 2, na caspase-1 e na proteína do grupo Box-1 de alta mobilidade após o teste de provocação com ovalbumina foram demonstradas por imuno-histoquímica. O ensaio dUTP Nick-End Labeling mediado por TdT, TUNEL e clivagem de caspase-3 e PARP-1 foram usados para a observação de piroptose. Resultados: Eosinofilia e infiltração de células caliciformes foram observadas na mucosa nasal de camundongos do grupo rinite alérgica. Inflamassoma ausente no melanoma 2, Asc e caspase-1 p20 aumentou após a exposição à ovalbumina, enquanto Nlrp3 não aumentou. A proteína do grupo Box-1 de alta mobilidade foi liberada na mucosa nasal de camundongos com rinite alérgica. As células TUNEL-positivas aumentaram no epitélio e na lâmina própria, enquanto a clivagem da caspase-3 e a PARP-1 não foram observadas. Conclusão: O inflamassoma ausente no melanoma 2 foi ativado e pode ocorrer piroptose na mucosa nasal após o tratamento com ovalbumina. Esses fatores podem contribuir para a translocação de proteína do grupo Box-1 de alta mobilidade e o desenvolvimento de rinite alérgica.
ABSTRACT
This study aimed to investigate the role of hypoxia-inducible factor-2α (HIF-2α) in the expression of tight junction proteins and permeability alterations in rat glomerular endothelial cells (rGENCs) under hypoxia conditions. The expression level of HIF-2α and tight junction proteins (occludin and ZO-1) in rGENCs were examined following 5% oxygen density exposure at different treatment times. HIF-2α lentivirus transfection was used to knockdown HIF-2α expression. Cells were divided into four groups: 1) control group (rGENCs were cultured under normal oxygen conditions), 2) hypoxia group (rGENCs were cultured under hypoxic conditions), 3) negative control group (rGENCs were infected with HIF-2α lentivirus negative control vectors and cultured under hypoxic conditions), and 4) Len group (rGENCs were transfected with HIF-2α lentivirus and cultured under hypoxic conditions). The hypoxia, negative control, and Len groups were kept in a hypoxic chamber (5% O2, 5% CO2, and 90% N2) for 24 h and the total content of occludin and ZO-1, and the permeability of rGENCs were assessed. With increasing hypoxia time, the expression of HIF-2α gradually increased, while the expression of occludin decreased, with a significant difference between groups. ZO-1 expression gradually decreased under hypoxia conditions, but the difference between the 24 and 48 h groups was not significant. The permeability of cells increased following 24-h exposure to hypoxia compared to the control group (P<0.01). The knockdown of HIF-2α expression significantly increased occludin and ZO-1 content compared with hypoxia and negative control groups (P<0.01), while permeability was reduced (P<0.01). Hypoxia increased HIF-2α content, inducing permeability of rGENCs through the reduced expression of occludin and ZO-1.
Subject(s)
Animals , Rats , Endothelial Cells/chemistry , Basic Helix-Loop-Helix Transcription Factors/metabolism , Occludin/metabolism , Zonula Occludens-1 Protein/metabolism , Kidney Glomerulus/cytology , Permeability , Time Factors , Cell Hypoxia/physiology , Endothelial Cells/metabolism , Cell ProliferationABSTRACT
Nasal polyp (NP) is a common chronic inflammatory disease of the nasal cavity and sinuses.Although some authors have suggested that NP is related to inflammatory factors such as interleukin (IL)-1β,IL-5,IL-8,granulocyte-macrophage colony-stimulating factor (GM-CSF),tumor necrosis factor (TNF)-α,and IL-17,the mechanisms underlying the pathogenesis and progression of NP remain obscure.This study investigated the expression and distribution of IL-17 and syndecan-1 in NP,and explored the roles of these two molecules in the pathogenesis of eosinophilic chronic rhinosinusitis with nasal polyps (Eos CRSwNP) and non-Eos CRSwNP.Real-time PCR and immunohistochemistry were used to detect the expression of IL-17 and syndecan-1 in samples [NP,unciform process (UP) from patients with CRS,and middle turbinate (MT) from healthy controls undergoing pituitary tumor surgery].The results showed that the expression levels of IL-17 and syndecan-1 were upregulated in both NP and UP tissues,but both factors were higher in NP tissues than in UP tissues.There was no significant difference in IL-17 levels between the Eos CRSwNP and non-Eos CRSwNP samples,and syndecan-1 levels were increased in the non-Eos CRSwNP tissues as compared with those in Eos CRSwNP tissues.In all of the groups,there was a close correlation between the expression of IL-17 and syndecan-1 in nasal mucosa epithelial cells,glandular epithelial cells,and inflammatory cells,suggesting that IL-17 and syndecan-1 may play a role,and interact with each other,in the pathogenesis ofnon-Eos CRSwNP.
ABSTRACT
Several studies have shown that hepatocyte growth factor (HGF) ameliorates renal interstitial fibrosis, but the mechanism is not fully clear. This study was designed to examine whether HGF can relieve renal interstitial injury in 5/6 nephrectomized rats, and to confirm whether this function was associated with decrease in -smooth muscle actin (-SMA) and transforming growth factor-beta1 (TGF-1) expression. The animals were randomized into 8 groups comprising 6 animals (n = 6) each: control (group I), PCI-neo (group II, 900 μg), sham-operation (group III，not nephrectomy), model or 5/6 nephrectomy group (group IV), lotensin group (an angiotensin converting enzyme inhibitor, group V, 0.6 mg/100 g/day for 5 weeks), low-dose PCI-neo-HGF group (group VI, 690 μg), high-dose PCI-neo-HGF group (group VII, 1380 μg) and lotensin + high-dose PCI-neo-HGF group (group VIII, 0.6 mg/100 g/day for 5 weeks, 1380 μg). The animals were sacrificed in the 5th week after 5/6 nephrectomy. The specimens of kidneys were used for pathological examination (hematoxylin-eosin staining), detection of -SMA and TGF-1 mRNA (Reverse transcriptase-polymerase chain reaction) and protein (Western blot and immunohistochemistry) expression. The results showed that in 5/6 nephrectomized rats blood urea nitrogen (BUN), serum creatinine (CRE) and 24 h urinary albumin excretion (UAE) were increased, renal interstitium was injured seriously and -SMA, TGF-1 mRNA and protein expression were elevated compared with those of control. The above changes were ameliorated and -SMA and TGF-1 expression was reduced by both PCI-neo-HGF and lotensin. The lotensin + high-dose PCI-neo-HGF group rats exhibited the most significant therapeutic effect both in decreasing the BUN, CRE and 24 h UAE and in relieving renal interstitial injury. In conclusion, the study demonstrated that HGF can relieve renal interstitial injury and this protection was associated with down-regulation of –SMA and TGF-1 expressions.