Dexmedetomidine protects against acute lung injury in mice via the DUSP1/MAPK/NF-κB axis by inhibiting miR-152-3p

Gen-17, a beta-methyl derivative of Genipin, attenuates LPS-induced ALI by regulating Keap1-Nrf2/HO-1 and suppressing NF-κB and MAPK-dependent signaling pathways

BACKGROUND AND OBJECTIVE

Acute lung injury (ALI) represents a complicated and debilitating pulmonary disorder for which therapeutic options are currently limited. Genipin is an aglycone derived from the geniposide, the most abundant iridoid glucoside constituent of Gardenia jasminoides Ellis, and has demonstrated beneficial effects in ALI. The objective of this study was to investigate the protective effect of Gen-17, a beta-methyl derivative of genipin, against ALI in vitro and in vivo, and explore its mechanism of action.

METHODS

In this study, we prepared a beta-methyl derivative of genipin, Gen-17, and assessed the antioxidative and anti-inflammatory effects of Gen-17 in LPS-induced murine macrophages and ALI in mice, and explored the mechanism of action of Gen-17. In an in vivo model, the impact of Gen-17 on lipopolysaccharide (LPS)-induced ALI in mice was investigated by assessing pro-inflammatory cytokine levels, lung histology, edema, and vascular and alveolar barrier integrity, and in an in vitro model, murine macrophages-Raw 264.7 cells were used to establish a cell model of inflammation and oxidative stress by incubating with LPS. Keap1-Nrf2/HO-1, NF-κB and MAPK signaling pathways related factors were tested in vitro and in vivo to explore the possible mechanism of Gen-17.

RESULTS

The study showed that administration of Gen-17 conferred protection against LPS-induced ALI in mice, characterized by the mitigation of histological lung tissue alterations, reduction in lung edema, diminished protein content in bronchoalveolar lavage fluid, attenuation of inflammatory cell infiltration, and a decrease in cytokine secretion. Furthermore, Gen-17 exhibited the capacity to inhibit the nuclear factor-kappa B (NF-κB) and extracellular signal-regulated kinase (ERK) in the context of LPS-induced lung injury. In vitro, research findings revealed that Gen-17 demonstrated notable efficacy in reducing oxidative stress and inflammation in RAW 264.7 cells induced by LPS. Its central mechanism of action revolved around enhancing the antioxidant defense pathway, mediated through nuclear factor erythroid 2-related factor 2 (Nrf2). Consequently, this intervention repressed the release of pro-inflammatory mediators initiated by LPS, along with the modulation of the mitogen-activated protein kinase (MAPK) signaling pathway.

CONCLUSION

Gen-17 demonstrates the ability to mitigate oxidative stress and inflammation in the context of LPS-induced ALI via modulation of the MAPK, NF-κBp65, and Keap1/Nrf2/heme oxygenase-1 (HO-1) pathways. As such, it emerges as a promising and novel therapeutic candidate for treating ALI.

Research status and advances in dexmedetomidine for sepsis‑induced multiple organ dysfunction syndrome (Review)

Sepsis‑induced organ dysfunction syndrome (ODS) arises from a dysregulated response to infection, leading to multiple life‑threatening organ dysfunctions, and is a common complication in critically ill patients. Sepsis results in varying degrees of injury to the brain, lungs, kidneys and liver, culminating in immune dysfunction and multiple ODS (MODS). Current evidence indicates a direct correlation between the severity of organ injury and the prognosis of septic patients. Understanding the mechanisms of MODS in sepsis and developing effective management strategies are vital research areas. The protective effects of dexmedetomidine (DEX) on sepsis are well established, demonstrating its capacity to mitigate injuries to the brain, lungs, kidneys, liver and immune system. The present study reviews recent research progress on the role and mechanisms of action of DEX in the treatment of sepsis.

Melatonin-Stimulated Mesenchymal Stem Cells-Derived Exosomes Carrying LINC00052 Alleviate Hyperoxic Lung Injury by Promoting miR-152-3p-KLF4-Nrf2 Pathway

Exposure of the lungs to high O2 levels, can lead to a noninfectious lung damage known as hyperoxia-induced lung injury (HILI). Melatonin stimulation can enhance the efficacy of stem cells in some diseases. This study aims to investigate the mechanism of exosomes secreted by mesenchymal stem cells (MSCs) stimulated by melatonin in HILI. The MSCs-derived exosomes were isolated and identified after stimulation with melatonin, and the neonatal rat model of HILI was constructed. After injection of exosomes and related lentiviruses, the ratio of wet lung to dry lung was calculated to evaluate pulmonary edema. Inflammatory factors in medium or serum were measured by ELISA. HE staining was used to evaluate the pathological status of lung tissue. Masson staining was used to evaluate collagen deposition in lung tissue. Lung cell apoptosis was detected by Tunel staining. In vitro model of HILI was established, CCK-8 and EDU staining were used to detect cell viability and proliferation, and flow cytometry was used to detect cell apoptosis. The binding relationship between LINC00052, miR-152-3p, and KLF4 was verified through bioinformatics websites, dual luciferase reporter experiments, RIP experiments, and RNA pull down experiments. Melatonin-stimulated MSCs-derived exosomes could alleviate HILI. Exosomes had a therapeutic effect on HILI neonatal rats by carrying LINC00052. Inhibition of LINC00052 reversed the therapeutic effect of exosomes on HILI, while low expression of miR-152-3p or inducing KLF4 negated the effect of sh-LINC00052. LINC00052 bound to miR-152-3p. miR-152-3p targeted KLF4. In vitro, melatonin-stimulated MSC-derived exosomes alleviated the cytotoxicity and cell viability inhibition of AEC-II cells induced by hyperoxia. KLF4 overexpression activated NRF2 signaling in AEC-II cells. LINC00052 in MSCs-derived exosomes stimulated by melatonin activates the Nrf2 pathway through the miR-152-3p/KLF4 axis to alleviate HILI, which may be a potential therapeutic approach for HILI.

Early growth response 1 regulates dual‑specificity protein phosphatase 1 and inhibits cell migration and invasion of tongue squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors in the head and neck, and among the OSCCs, tongue squamous cell carcinoma (TSCC) is one of the most common types. Although therapy strategies have recently advanced, the prognosis of TSCC has not substantially improved. Metastasis is one of the main causes of patient mortality in TSCC; therefore, it is necessary to elucidate the mechanism by which TSCC metastasis is regulated. In the present study, the early growth response 1 (Egr-1) expression in TSCC was analyzed based on GEO datasets and the effect of Egr-1 in TSCC tumor cell migration and invasion was measured using Transwell assay. By overexpressing dual-specificity protein phosphatase 1 (DUSP1) in cells with Egr-1 knockdown using lentivirus infection, the role of DUSP1 in Egr-1-regulated TSCC cell migration and invasion was determined. By using luciferase and ChIP assays, the mechanism behind how DUSP1 is regulated by Egr-1 was detected. In the present study, it was demonstrated that Egr-1 was downregulated in TSCC and the knockdown of Egr-1 increased TSCC cell migration and invasion. The expression of Egr-1 was also correlated with DUSP1. The overexpression of DUSP1 in Egr-1 knockdown cells, reduced the level of cell migration and invasion. Furthermore, it was demonstrated that knockdown of Egr-1 inhibited the promoter activity of DUSP1 and the site through which Egr-1 regulates DUSP1 transcription was identified. In conclusion, the present study demonstrated that Egr-1 regulates TSCC cell migration and invasion through modulating DUSP1, suggesting the potential of Egr-1 and DUSP1 as therapy targets for TSCC.