The expression of miR‐125b in Nrf2‐silenced A549 cells exposed to hyperoxia and its relationship with apoptosis

Abstract

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that affects the quality of life of infants. At present, premature exposure to hyperoxia for extended periods of time is believed to affect the development of lung tissue and vascularity, resulting in BPD. The oxidative stress caused by hyperoxia exposure is an important risk factor for BPD in premature infants. Nuclear factor E2‐related factor 2 (Nrf2) is an important regulator of antioxidant mechanisms. As a microRNA, microRNA‐125b (miR‐125b) plays an important role in cell proliferation, differentiation and apoptosis. Although the Nrf2/ARE pathway has been extensively studied, little is known about the regulatory role of microRNAs in Nrf2 expression. In this study, the expression levels of Nrf2 and miR‐125b in the lung tissues of premature Sprague Dawley (SD) rats and A549 cells exposed to hyperoxia were detected by quantitative real‐time polymerase chain reaction (qRT‐PCR), and the apoptosis of A549 cells was detected by flow cytometry. The results showed that Nrf2 and miRNA‐125b in the lung tissues of premature rats increased significantly upon exposure to hyperoxia and played a protective role. Nrf2 was suppressed by small interfering RNA (siRNA) in A549 cells, miR‐125b was similarly inhibited, and apoptosis was significantly increased. These results suggest that miR‐125b helps protect against BPD as a downstream target of Nrf2.

Peptidome Analysis of Umbilical Cord Mesenchymal Stem Cell (hUC-MSC) Conditioned Medium from Preterm and Term Infants

“…Given the large predominance of in ammation in the pathogenesis of BPD, we focused on the effect of peptides on in ammation response. A549 cells, a human lung carcinoma cell line, are often used for researches in pathological mechanism and treatment of BPD by A549 cells [69,70]. And in our study, H 2 O 2 , known as a strong two-electron oxidant, could induce the production fo TNF-α, IL-1β and IL-6 in human lung epithelial cell line A549 in agreement with previous studies [71].…”

“…And in our study, H 2 O 2 , known as a strong two-electron oxidant, could induce the production fo TNF-α, IL-1β and IL-6 in human lung epithelial cell line A549 in agreement with previous studies [71]. As known to all, primary human AEC are di cult to isolate and culture and also are mutable and unsuitable for experimental intervention, while A549 cells have similar biological characteristics to AEC cells [72]. Although embryonic alveolar epithelial cells are more in line with the purpose of the project, and can be better used to evaluate the effects of peptides on the characteristics of lung development.…”

“…Although embryonic alveolar epithelial cells are more in line with the purpose of the project, and can be better used to evaluate the effects of peptides on the characteristics of lung development. However, this cell is di cult to obtain and easy to mutate [72]. Thus, we chose human lung epithelial cells A549 to explore the effects of differentially expressed peptides in vitro.…”

Long non‐coding RNA MALAT1 targeting STING transcription promotes bronchopulmonary dysplasia through regulation of CREB

“…31 Another factor is oxidative stress that may lead to the stimulation of inflammatory cells, activation of pro-inflammatory cytokines, impairment or apoptosis of respiratory tract epithelium. 32,33 F I G U R E 4 Silencing both STING and MALAT1 promoted the proliferation and repressed the apoptosis of cells. A, pcDNA3.1-STING or the empty vector, siRNA-STING or siRNA-NC and siRNA-MALAT1 or siRNA-NC were transfected into A549 cells.…”

Peptidome analysis of umbilical cord mesenchymal stem cell (hUC-MSC) conditioned medium from preterm and term infants

“…Given the large predominance of inflammation in the pathogenesis of BPD, we focused on the effect of peptides on inflammation response. A549 cells, a human lung carcinoma cell line, are often used for researches in pathological mechanism and treatment of BPD by A549 cells [ 68 , 69 ]. And in our study, H 2 O 2 , known as a strong two-electron oxidant, could induce the production for TNF-α, IL-1β, and IL-6 in human lung epithelial cell line A549 in agreement with previous studies [ 70 ].…”