The Notch pathway attenuates burn-induced acute lung injury in rats by repressing reactive oxygen species

Abstract

Background Acute lung injury (ALI) is a common complication following severe burns. The underlying mechanisms of ALI are incompletely understood; thus, available treatments are not sufficient to repair the lung tissue after ALI. Methods To investigate the relationship between the Notch pathway and burn-induced lung injury, we established a rat burn injury model by scalding and verified lung injury via lung injury evaluations, including hematoxylin and eosin (H&E) staining, lung injury scoring, bronchoalveolar lavage fluid and wet/dry ratio analyses, myeloperoxidase immunohistochemical staining and reactive oxygen species (ROS) accumulation analysis. To explore whether burn injury affects Notch1 expression, we detected the expression of Notch1 and Hes1 after burn injury. Then, we extracted pulmonary microvascular endothelial cells (PMVECs) and conducted Notch pathway inhibition and activation experiments, via a γ-secretase inhibitor (GSI) and OP9-DLL1 coculture, respectively, to verify the regulatory effect of the Notch pathway on ROS accumulation and apoptosis in burn-serum-stimulated PMVECs. To investigate the regulatory effect of the Notch pathway on ROS accumulation, we detected the expression of oxidative-stress-related molecules such as superoxide dismutase, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) 2, NOX4 and cleaved caspase-3. NOX4-specific small interfering RNA (siRNA) and the inhibitor GKT137831 were used to verify the regulatory effect of the Notch pathway on ROS via NOX4. Results We successfully established a burn model and revealed that lung injury, excessive ROS accumulation and an inflammatory response occurred. Notch1 detection showed that the expression of Notch1 was significantly increased after burn injury. In PMVECs challenged with burn serum, ROS and cell death were elevated. Moreover, when the Notch pathway was suppressed by GSI, ROS and cell apoptosis levels were significantly increased. Conversely, these parameters were reduced when the Notch pathway was activated by OP9-DLL1. Mechanistically, the inhibition of NOX4 by siRNA and GKT137831 showed that the Notch pathway reduced ROS production and cell apoptosis by downregulating the expression of NOX4 in PMVECs. Conclusions The Notch pathway reduced ROS production and apoptosis by downregulating the expression of NOX4 in burn-stimulated PMVECs. The Notch–NOX4 pathway may be a novel therapeutic target to treat burn-induced ALI.

Identification of ferroptosis-related genes and predicted overall survival in patients with burns

“…Enrichment analysis through GO-BP shows significant involvement of these genes in oxidative stress, pyridine-containing compound metabolic process, and reactive oxygen species metabolic process. Although, to our knowledge, there is no exact experimental evidence of ferroptosis in burns, ROS accumulation and lipid peroxidation can be observed in the serum of burn patients (24,25). Antioxidants were shown to significantly reduce injury and edema after burns (26-28).…”

Global research progress of endothelial cells and ALI/ARDS: a bibliometric analysis

“…Specifically, they delve into the diverse molecular mechanisms and signaling pathways that modulate oxidative stress, and through this avenue, several novel regulatory molecules and pathways have been identified that can ameliorate ECs damage by inhibiting oxidative stress, thereby providing new avenues for improving the clinical status of ALI/ARDS. For instance, Cai et al ( Cai et al, 2022 ) revealed in a study on burn-induced acute lung injury (ALI) that activation of the Notch pathway in pulmonary microvascular endothelial cells (PMVECs) significantly reduced ROS production and cell apoptosis by downregulating NOX4 expression. This study elucidated the critical role of the Notch-NOX4 signaling pathway in regulating ROS generation and cell apoptosis in PMVECs, thus offering a new therapeutic target for burn-induced ALI.…”

The molecular pathogenesis of triptolide-induced hepatotoxicity

“…Activation of the Notch1 signaling pathway has been shown to reduce oxidative stress in injured tissues ( Cai et al, 2022 ). The thioredoxin (TRX) system is a key antioxidant system against oxidative stress ( Lu and Holmgren, 2014 ).…”