Expression of Nodal on Bronchial Epithelial Cells Influenced by Lung Microbes Through DNA Methylation Modulates the Differentiation of T-Helper Cells

Background: Heat causes bronchial epithelial cell apoptosis, which is a known factor contributing to airway damage during inhalation injury. Accumulating evidence has shown the effect of curcumin on inhibiting apoptosis. In this study, we investigated whether curcumin suppresses heat-induced apoptosis in bronchial epithelial cells and the underlying mechanism. Methods: Bronchial epithelial cell line 16HBE140 cells were incubated at either 42 °C, 47 °C, 52 °C, or 57 °C for 5 min in a cell incubator and then returned back to normal culture conditions (37 °C). An in vivo thermal inhalation injury rat model was established with a heat gun blowing hot air into the airway of rats. 16HBE140 cells and lung tissue were obtained for further study with or without curcumin treatment. Cell viability was determined by measuring the absorbance of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). 2',7'-dichlorofluorescein diacetate fluorescence was used as a measure of reactive oxygen species (ROS) production. Levels of Bcl2, Bax, α-ATP, cleaved Poly (ADP-ribose) polymerase (PARP), cleaved caspase-3, gp91^phox, p47^phox, p67^phox, p22^phox, p40^phox, and Rac were determined by Western blotting. TUNEL staining was used to determine apoptosis. Results: Heat treatment triggered the apoptosis of 16HBE140 cells as shown by the increase in apoptosis molecular markers, including Bcl-2, Bax, cleaved PARP, and cleaved caspase-3. Administration of curcumin significantly inhibited apoptosis of 16HBE140 cells and suppressed the membrane translocation of NADPH oxidase 2 cytosolic components, as well as ROS production. Downregulation of Akt and mTOR phosphorylation induced by heat was also reversed by curcumin. Furthermore, we demonstrated that NADPH oxidase 2 is upstream of Akt/mTOR in heat-induced apoptosis. The protective role of curcumin on bronchial epithelia apoptosis was also confirmed in vivo by a rat inhalation injury model. Conclusion: This study demonstrates that one of the critical mechanisms underlying curcumin inhibiting heat-induced apoptosis is through suppressing NADPH Oxidase 2 and activating the Akt/mTOR signaling pathway in bronchial epithelial cells.

Section: Discussionmentioning

confidence: 99%

Curcumin Inhibits Heat-Induced Apoptosis by Suppressing NADPH Oxidase 2 and Activating the Akt/mTOR Signaling Pathway in Bronchial Epithelial Cells

Yuan

Tang

et al. 2017

“…The ΔCt (average Ct-average Ct of Homo-18SrRNA) and ΔΔCt [ΔΔCt=ΔCt (experimental)-ΔCt (control)] were calculated. The relative expression was calculated from experimental to control as 2 -ΔΔCt [12]. …”

Section: Methodsmentioning

confidence: 99%

Emodin: One Main Ingredient of Shufeng Jiedu Capsule Reverses Chemoresistance of Lung Cancer Cells Through Inhibition of EMT

Yuan

Liao²,

Xue

et al. 2017

Background: Chemoresistance has become a an important worldwide problem to cancer treatment. Understanding the mechanism of drug resistance is the key to solve this problem and improve the survival of the patient. Doxorubicin and its analogues are widely used as antitumor drugs but many doxorubicin resistant cases have been identified in recent years. Doxorubicin (Dox) resistance is a very serious phenomenon in lung cancer treatment. As we could show previously, Shufeng Jiedu Capsule (SFJDC) can effectively reverse H69AR cells resistance to Dox, thus, the present study was designed to explore the mechanism underlying the effects of the main ingredient Emodin on chemosensitivity of H69AR cells to Dox. Methods: First, the growth inhibition rate of lung cancer cells and normal bronchial epithelial cells (BECs) was determined by MTT. Then, the resistance-induced epithelial-mesenchymal transition (EMT) of H69AR cells was examined by western blot and the effect of Emodin on Twist, Snail or Slug was assayed by Real-time PCR and Western blot. The activation of NF-kappa B was assayed by Western blot. Proliferation, apoptosis, migration and invasion of H69AR cells induced by Twist, Snail and Slug were also assayed by flow cytometry and transwell chamber. Results: The results showed that after administration of Dox (10µM) with different concentrations of Emodin, the cells exhibited a dose-dependent inhibition action to H69AR cells at 48 hours. H69AR induced the expression of Twist, Snail, and Slug when compared with Dox-sensitive H69 cells. The expression of Twist, Snail, and Slug can be effectively inhibited by combination of Dox and Emodin. The reversal of resistance was associated with the inhibition of NF-kappa B. Twist, Snail and Slug promoted proliferation, migration and invasion and inhibited apoptosis. Conclusion: Our data suggest that Emodin can effectively reverse the resistance of H69AR to Dox, an effect paralleled by inhibition of EMT, cell proliferation, apoptosis, migration and invasion.

“…Th1-mediated IFN-γ and tumor necrosis factor (TNF) production are known to promote M1 macrophage differentiation and increase the expression of MHC molecules [14], allowing increased antigen-presentation to CD4 + and CD8 + T cells and increased proinflammatory cytokine expression. Th17 cells also secrete TNF in addition to IL-17 and are implicated in multiple inflammatory mechanisms [15]. Interestingly, AMD patients presented increased serum levels of proinflammatory cytokines, including IL-1β, TNF, and IL-17 [16].…”

Section: Introductionmentioning

confidence: 99%

Increased Th1/Th17 Responses Contribute to Low-Grade Inflammation in Age-Related Macular Degeneration

Chen

Wang

2017

Background/Aims: Age-related macular degeneration (AMD) is the primary cause of senior blindness in developed countries. Mechanisms underlying initiation and development of AMD remained known. Methods: We examined the CD4 + T cell compartments and their functions in AMD patients. Results: AMD patients presented significantly higher frequencies of interferon (IFN)-γ-expressing and interleukin (IL)-17-expressing CD4 + T cells than healthy controls. The levels of IFN-γ and IL-17 expression by CD4 + T cells were significantly higher in AMD patients. These IFN-γ-expressing Th1 cells and IL-17-expressing Th17 cells could be selectively enriched by surface CCR3 + and CCR4 + CCR6 + expression, respectively. Th1 and Th17 cells from AMD patients promoted the differentiation of monocytes toward M1 macrophages, which were previously associated with retinal damage. Th1 and Th17 cells also increased the level of MHC class I expression in human retinal pigment epithelial (RPE)-1 cells, while Th1 cells increased the frequency of MHC class II-expressing RPE-1 cells. These proinflammatory effects were partly, but not entirely, induced by the secretion of IFN-γ and IL-17. Conclusions: This study demonstrated an enrichment of Th1 cells and Th17 cells in AMD patients. These Th1 and Th17 cells possessed proinflammatory roles in an IFN-γ-and IL-17-dependent fashion, and could potentially serve as therapeutic targets.