Resveratrol inhibits mucin gene expression, production and secretion from airway epithelial cells

The study investigated whether resveratrol significantly affects mucin gene expression, production and secretion from airway epithelial cells. Confluent NCI‐H292 cells were pretreated with resveratrol for 30 min and then stimulated with EGF (epidermal growth factor), PMA (phorbol 12‐myristate 13‐acetate) and TNF‐α (tumor necrosis factor‐α) for 24 h, respectively. The MUC5AC gene expression and mucin protein production were measured by RT‐PCR and ELISA. The effect of resveratrol on TNF‐α‐ or PMA‐induced activation of NF‐κB p65 was also examined. Confluent primary rat tracheal surface epithelial (RTSE) cells were pretreated with adenosine triphosphate (ATP) for 5 min and then treated for 30 min in the presence of resveratrol to assess the effect on mucin secretion using ELISA. The results were as follows: (1) resveratrol inhibited the expression of MUC5AC gene induced by EGF or PMA or TNF‐α from NCI‐H292 cells; (2) resveratrol also inhibited the production of MUC5AC mucin protein induced by the same inducers from NCI‐H292 cells; (3) resveratrol inhibited the activation of NF‐κB p65 by TNF‐α or PMA in NCI‐H292 cells; (4) resveratrol significantly decreased ATP‐induced mucin secretion from cultured RTSE cells. This result suggests that resveratrol can regulate mucin gene expression, production and secretion, by directly acting on airway epithelial cells. Copyright © 2011 John Wiley & Sons, Ltd.     

A New Isoflavone Glycitein 7‐O‐beta‐d‐Glucoside 4'‐O‐methylate,isolated from Cordyceps militaris grown on Germinated Soybeans Extract,Inhibits EGF‐induced Mucus Hypersecretion in the Human Lung Mucoepidermoid Cells

A new isoflavone glycitein 7‐O‐beta‐d ‐glucoside 4''‐O‐methylate (CGLM) has been isolated recently from Cordyceps militaris grown on germinated soybean extract and has antioxidant activity. In the present study, CGLM was investigated for its suppression of airway mucous hyper‐secretion in epidermal growth factor (EGF)‐treated human lung mucoepidermoid cells. NCI‐H292 cells were treated with CGLM for 1 h, followed by EGF treatment for 24 h. The decrease in cyclooxygenase‐2 (COX‐2) production was correlated with reduced levels of protein and mRNA of inducible matrix metalloproteinase 9 (MMP‐9) and also MUC5AC gene expression. CGLM directly inhibited down‐regulated NF‐κB activity, and significantly inhibited the phosphorylation of p38 and ERK1/2 (p42/p44) in NCI‐H292 cells. These results suggest that CGLM protects NCI‐H292 cells from EGF‐induced damage by down‐regulation of COX‐2, MMP‐9 and MUC5AC gene expression, mediated via blocking the NF‐kappa‐B and p38/ERK MAPK pathways. Copyright © 2012 John Wiley & Sons, Ltd.     

Diosmetin exhibits anti‐proliferative and anti‐inflammatory effects on TNF‐α‐stimulated human rheumatoid arthritis fibroblast‐like synoviocytes through regulating the Akt and NF‐κB signaling pathways

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by inflammation and proliferation of synovial tissues. Diosmetin is a bioflavonoid possessing an anti‐inflammatory property. Herein, we aimed to study the effects of diosmetin on the inflammation and proliferation of RA fibroblast‐like synoviocytes MH7A cells. MH7A cell proliferation was measured using cell counting kit‐8 assay. Cell apoptosis was examined using flow cytometry. The production of inflammatory cytokines including interleukin (IL)‐1β, IL‐6, IL‐8, and matrix metalloproteinase‐1 (MMP‐1) was measured using enzyme‐linked immunosorbent assay (ELISA). Results showed that diosmetin inhibited tumor necrosis factor‐α (TNF‐α)‐induced proliferation increase in MH7A cells in a dose‐dependent manner. Diosmetin treatment resulted in an increase in apoptotic rates and a reduction in TNF‐α‐induced production of IL‐1β, IL‐6, IL‐8, and MMP‐1 in MH7A cells. Furthermore, diosmetin inhibited TNF‐α‐induced activation of protein kinase B (Akt) and nuclear factor‐κB (NF‐κB) pathways in MH7A cells. Suppression of Akt or NF‐κB promoted apoptosis and inhibited TNF‐α‐induced proliferation increase and production of IL‐1β, IL‐6, IL‐8, and MMP‐1 in MH7A cells, and diosmetin treatment enhanced these effects. Taken together, these findings suggested that diosmetin exhibited anti‐proliferative and anti‐inflammatory effects via inhibiting the Akt and NF‐κB pathways in MH7A cells.     

Oleanolic acid and ursolic acid derived from Cornus officinalis Sieb. et Zucc. suppress epidermal growth factor- and phorbol ester-induced MUC5AC mucin production and gene expression from human airway epithelial cells

In this study, the effects of oleanolic acid and ursolic acid on MUC5AC mucin production and gene expression induced by epidermal growth factor (EGF) and phorbol 12‐myristate 13‐acetate (PMA) from human airway epithelial cells were investigated. Confluent NCI‐H292 cells were pretreated with each agent for 30 min and then stimulated with EGF and PMA for 24 h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by RT‐PCR and ELISA. Oleanolic acid and ursolic acid were found to inhibit the production of MUC5AC mucin protein induced by EGF and PMA, and both compounds also inhibited the expression of MUC5AC mucin gene induced by EGF and PMA. These results suggest that oleanolic acid and ursolic acid can regulate mucin gene expression, and production of mucin protein, by directly acting on airway epithelial cells. Copyright © 2011 John Wiley & Sons, Ltd.     

Myrislignan Attenuates Lipopolysaccharide‐induced Inflammation Reaction in Murine Macrophage Cells Through Inhibition of NF‐κB Signalling Pathway Activation

Myrislignan is a new kind of lignan isolated from Myristica fragrans Houtt. Its antiinflammatory effects have not yet been reported. In the present study, the antiinflammatory effects and the underlying mechanisms of myrislignan in lipopolysaccharide (LPS)‐induced inflammation in murine RAW 264.7 macrophage cells were investigated. Myrislignan significantly inhibited LPS‐induced production of nitric oxide (NO) in a dose‐dependent manner. It inhibited mRNA expression and release of interleukin‐6 (IL‐6) and tumour necrosis factor‐α (TNF‐α). This compound significantly inhibited mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase‐2 (COX‐2) dose‐dependently in LPS‐stimulated macrophage cells. Further study showed that myrislignan decreased the cytoplasmic loss of inhibitor κB‐α (IκB‐α) protein and the translocation of NF‐κB from cytoplasm to the nucleus. Our results suggest that myrislignan may exert its antiinflammatory effects in LPS‐stimulated macrophages cells by inhibiting the NF‐κB signalling pathway activation. Copyright © 2012 John Wiley & Sons, Ltd.     

Praeruptorin a inhibits lipopolysaccharide‐induced inflammatory response in murine macrophages through inhibition of NF‐κB pathway activation

Praeruptorin A (PA) is a pyranocoumarin compound isolated from the dried root of Peucedanum praeruptorum Dunn (Umbelliferae). However, the antiinflammatory effect of PA has not been reported. The present study investigated the antiinflammatory effect of PA in lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophage cells. PA significantly inhibited the LPS‐induced production of nitric oxide (NO), interleukin‐1β (IL‐1β) and tumor necrosis factor‐α (TNF‐α). The mRNA and protein expressions of inducible nitric oxide synthase (iNOS), IL‐1β and TNF‐α were also suppressed by this compound. Further study showed that PA decreased the cytoplasmic loss of inhibitor κB‐α (IκB‐α) protein and inhibited the translocation of NF‐κB from cytoplasm to nucleus. Taken together, the results suggest that PA may exert antiinflammatory effects in vitro in LPS‐stimulated RAW 264.7 macrophages through inhibition of NF‐κB signal pathway activation. Copyright © 2010 John Wiley & Sons, Ltd.     

The anti‐inflammatory effect of baicalin on hypoxia/reoxygenation and TNF‐α induced injury in cultural rat cardiomyocytes

The aim of present study was to investigate the effect of baicalin on hypoxia/reoxygenation (H/R) injury in cardiomyocytes and the mechanisms involved, particularly in relation to cytokines. The cardiomyocytes for the H/R groups were placed into a hypoxic chamber for 12 h and then underwent reoxygenation for 1 h. The cells in the TNF‐α groups were administered 100 ng/mL rrTNF‐α and incubated for 13 h under normal conditions. The cells in the baicalin pretreatment groups were administered 10 μM baicalin 30 min prior to exposure to H/R or TNF‐α. It was observed that pretreatment with baicalin (10 μM) significantly reduced the cell damage and death induced by H/R or TNF‐α. In the culture medium of the H/R cells, the SOD activity increased, while TNF‐α was decreased by baicalin. The levels of IL‐6 in culture medium for H/R or TNF‐α treated cells were suppressed by baicalin pretreatment. In contrast, the levels of IL‐10 in culture medium for H/R or TNF‐α treated cells were significantly elevated by baicalin. Moreover, baicalin inhibited the nuclear translocation of NF‐κB induced by H/R or TNF‐α. In conclusion, baicalin may protect cardiomyocytes from H/R injury through an anti‐inflammatory mechanism. Copyright © 2009 John Wiley & Sons, Ltd.     

Hydroxy‐Safflower Yellow A inhibits the TNFR1‐Mediated Classical NF‐κB Pathway by Inducing Shedding of TNFR1

Hydroxy‐safflower yellow A (HSYA) is the major active component of safflower, a traditional Asia herbal medicine well known for its cardiovascular protective activities. The purpose of this study was to investigate the effect of HSYA on TNF‐α‐induced inflammatory responses in arterial endothelial cells (AECs) and to explore the mechanisms involved. The results showed that HSYA suppressed the up‐regulation of ICAM‐1 expression in TNF‐α‐stimulated AECs in a dose‐dependent manner. High concentration (120 μM) HSYA significantly inhibited the TNF‐α‐induced adhesion of RAW264.7 cells to AECs. HSYA blocked the TNFR1‐mediated phosphorylation and degradation of IκBα and also prevented the nuclear translocation of NF‐κB p65. Moreover, HSYA reduced the cell surface level of TNFR1 and increased the content of sTNFR1 in the culture media. TNF‐α processing inhibitor‐0 (TAPI‐0) prevented the HSYA inhibition of TNFR1‐induced IκBα degradation, implying the occurrence of TNFR1 shedding. Furthermore, HSYA induced phosphorylation of TNF‐α converting enzyme (TACE) at threonine 735, which is thought to be required for its activation. Conclusively, HSYA suppressed TNF‐α‐induced inflammatory responses in AECs, at least in part by inhibiting the TNFR1‐mediated classical NF‐κB pathway. TACE‐mediated TNFR1 shedding can be involved in this effect. Our study provides new evidence for the antiinflammatory and anti‐atherosclerotic effects of HSYA. Copyright © 2016 John Wiley & Sons, Ltd.     

Anti‐inflammatory Effects of Ginsenosides Rg5, Rz1, and Rk1: Inhibition of TNF‐α‐induced NF‐κB,COX‐2, and iNOS transcriptional expression

In the course of this experiment on the anti‐inflammatory effect of ginsenosides, protopanaxdiol ginsenosides have shown inhibition activities in inflammatory responses: NF‐κB, COX‐2, and iNOS were induced by TNF‐α. The responses of this experiment were evaluated by NF‐κB‐luciferase assay and RT‐PCR experiment of COX‐2 and iNOS genes. The NF‐κB expressions were inhibited by ginsenosides Rd, Rg₅, Rz₁, and Rk₁ in a dose‐dependent manner. The IC₅₀ values were 3.47, 0.61, 0.63, and 0.75 μM, respectively. Particularly, ginsenosides Rg₅, Rz₁, and Rk₁ as converted ginsenosides from primary protopanaxdiol ginsenosidess significantly inhibited COX‐2 and iNOS gene expression. These inhibition levels were similar to sulfasalazine as reference material. Copyright © 2014 John Wiley & Sons, Ltd.     

Kaempferol and quercetin,essential ingredients in Ginkgo biloba extract,inhibit interleukin‐1β‐induced MUC5AC gene expression in human airway epithelial cells

According to our previous study, Ginkgo biloba extract (GBE) suppresses IL‐1β‐induced MUC5AC gene expression in NCI‐H292 cells via the ERK and p38 MAPK pathways. This study sought to identify which ingredients of GBE suppress IL‐1β‐induced MUC5AC gene expression in NCI‐H292 cells and to examine which MAPKs are related to MUC5AC gene suppression for each ingredient. After the cells were pretreated with each ingredient and treated with IL‐1β (10 ng/mL), MUC5AC mRNA expression was determined by RT‐PCR and real‐time PCR. The results showed that kaempferol (KP) and quercetin (QC) suppressed MUC5AC mRNA expression in a dose‐dependent manner, both with significant inhibition starting from 40 µm (equal concentration to about a twelfth or thirteenth dose of GBE). MAPK proteins were determined by western blot analysis after pretreatment with KP, QC and GBE. All three suppressed the phosphorylation of ERK and p38 kinases. In conclusion, the data suggested that KP and QC, essential ingredients in GBE, may overcome the dose problem of GBE and play a valuable role, clinically, in controlling mucin hypersecretion in airway inflammation. Copyright © 2009 John Wiley & Sons, Ltd.