A synthetic chalcone derivative, compound 39, alleviates lipopolysaccharide-induced acute lung injury in mice

Evidence that a Novel Chalcone Derivative, Compound 27, Acts on the Epithelium Via the PI3K/AKT/Nrf2-Keap1 Signaling Pathway, to Mitigate LPS-Induced Acute Lung Injury in Mice

Acute lung injury (ALI) is a highly heterogeneous clinical syndrome and an important cause of mortality in critically ill patients, with limited treatment options currently available. Chalcone, an essential secondary metabolite found in edible or medicinal plants, exhibits good antioxidant activity and simple structure for easy synthesis. In our study, we synthesized a novel chalcone derivative, compound 27 (C27). We hypothesized that C27 could be a potential treatment for acute respiratory distress syndrome (ARDS). Therefore, the protective effects of C27 on lung epithelial cells during ALI and the underlying molecular mechanisms were investigated. In vivo, Intratracheal instillation of LPS (10 mg/kg) was used to induce acute lung injury in mice. In vitro, the bronchial epithelial cell line (Beas-2b) was treated with 30 μM tert-butyl hydroperoxide (t-BHP) to simulate oxidative stress. Our findings demonstrate that pretreatment with C27 reduces LPS-induced oxidative destruction and cellular apoptosis in lung tissues of mice. Furthermore, it significantly attenuates t-BHP-induced cellular reactive oxygen species (ROS) generation, mitochondrial damage, and apoptosis in vitro. Mechanistically, the signaling pathway involving Nrf2-Keap1 and the downstream antioxidative proteins were activated by C27 in vivo. Additionally, PI3K inhibitor LY294002 and Nrf2 inhibitor ML385 abolished the effect of C27 in vitro, indicating that the protective effect of C27 is mediated via the PI3K/AKT/Nrf2-Keap1 pathway. Our study provides evidence that C27 protects against LPS-induced ALI by mitigating oxidative stress via activation of the PI3K/AKT/Nrf2-Keap1 signaling pathway. Therefore, we hypothesize that C27 represents a viable alternative for ALI therapy.

Extracellular Vesicles Derived from Human Adipose-Derived Mesenchymal Stem Cells Alleviate Sepsis-Induced Acute Lung Injury through a MicroRNA-150-5p-Dependent Mechanism

Extracellular vesicles (EVs) derived from human adipose mesenchymal stem cells (hADSCs) may exert a therapeutic benefit in alleviating sepsis-induced organ dysfunction by delivering cargos that include RNAs and proteins to target cells. The current study aims to explore the protective effect of miR-150-5p delivered by hADSC-EVs on sepsis-induced acute lung injury (ALI). We noted low expression of miR-150-5p in plasma and bronchoalveolar lavage fluid samples from patients with sepsis-induced ALI. The hADSC-EVs were isolated and subsequently cocultured with macrophages. It was established that hADSC-EVs transferred miR-150-5p to macrophages, where miR-150-5p targeted HMGA2 to inhibit its expression and, consequently, inactivated the MAPK pathway. This effect contributed to the promotion of M2 polarization of macrophages and the inhibition of proinflammatory cytokines. Further, mice were made septic by cecal ligation and puncture in vivo and treated with hADSC-EVs to elucidate the effect of hADSC-EVs on sepsis-induced ALI. The in vivo experimental results confirmed a suppressive role of hADSC-EVs in sepsis-induced ALI. Our findings suggest that hADSC-EV-mediated transfer of miR-150-5p may be a novel mechanism underlying the paracrine effects of hADSC-EVs on the M2 polarization of macrophages in sepsis-induced ALI.