miR-9 targeting RUNX1 improves LPS-induced alveolar hypercoagulation and fibrinolysis inhibition through NF-κB inactivation in ARDS

Astragaloside IV Inhibits Lung Injury and Fibrosis Induced by PM2.5 by Targeting RUNX1 Through miR-362-3p

To discover the molecular mechanism of Astragaloside IV (AS IV) in PM2.5-induced lung injury and pulmonary fibrosis (PF). A lung injury rat model was induced by PM2.5 and injected intraperitoneally with AS IV. Lungs were harvested to evaluate lung tissue injury and apoptosis. Rat alveolar epithelial cells L2 were exposed to PM2.5 and treated with AS IV. After cellular transfection, cell proliferation, LDH production, and apoptosis were measured. In both models, inflammatory factors and fibrotic indices were measured by ELISA and Western blot. miR-362-3p and RUNX1 interplay was explored and confirmed. Administration of AS IV attenuated PM2.5-induced lung tissue injury, inflammation, apoptosis, and PF in rats. AS IV enhanced proliferation and reduced LDH release, apoptosis, inflammation, and PF in PM2.5-treated L2 cells. MiR-362-3p upregulation improved PM2.5-induced L2 cell injury. AS IV improved PM2.5-induced lung injury by upregulating miR-362-3p. miR-362-3p had an inhibition effect on RUNX1 expression. RUNX1 upregulation weakened the therapeutic effect of AS IV on PM2.5-induced alveolar epithelial cell injury. AS IV inhibits lung injury and PF induced by PM2.5 by targeting RUNX1 through upregulation of miR-362-3p.

Role of miR-9 in Modulating NF-κB Signaling and Cytokine Expression in COVID-19 Patients

Coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, has had a significant impact on global health, with severe cases often characterized by a worsening cytokine storm. Since it has been described that the NF-κB signaling pathway, regulated by microRNAs, could play a pivotal role in the inflammatory response, in this study, the role of miR-9 in modulating NF-κB signaling and inflammatory cytokine expression in COVID-19 patients was investigated. This observational retrospective single-center study included 41 COVID-19 patients and 20 healthy controls. Serum samples were analyzed for miR-9, NF-κB, and IκBα expression levels using RT-PCR. The expression levels and production of pro-inflammatory cytokines IL-6, IL-1β, and TNF-α were measured using RT-PCR and ELISA. Statistical analyses, including correlation and regression, were conducted to explore relationships between these variables. COVID-19 patients, particularly non-survivors, exhibited significantly higher miR-9 and NF-κB levels compared to controls. A strong positive correlation was found between miR-9 and NF-κB expression (r = 0.813, p < 0.001). NF-κB levels were significantly correlated with IL-6 (r = 0.971, p < 0.001), IL-1β (r = 0.968, p < 0.001), and TNF-α (r = 0.968, p < 0.001). Our findings indicate that miR-9 regulates NF-κB signaling and inflammation in COVID-19. Elevated miR-9 levels in non-survivors suggest its potential as a severity biomarker. While COVID-19 cases have decreased, targeting miR-9 and NF-κB could improve outcomes for other inflammatory conditions, including autoimmune diseases, highlighting the need for continued research in this area.

MiR-202-3p Targets Calm1 and Suppresses Inflammation in a Mouse Model of Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is regarded as a type of respiratory failure. Emerging evidence has demonstrated the significant roles of microRNAs in various disorders. Nevertheless, the role of miR-202-3p in ARDS is unclear. Forty male C57BL/6 mice treated with phosphate buffer saline/lipopolysaccharide (PBS/LPS) and administrated with NC/miR-202-3p agomir were divided into four groups. A reverse transcription-quantitative polymerase chain reaction was used to evaluate the level of miR-202-3p, its target genes, and proinflammatory factors. Hematoxylin‑eosin was utilized for histological observation of the lung tissues. The Wet/Dry ratio, myeloperoxidase activity, and total protein concentration in bronchoalveolar lavage fluid were assessed to determine pulmonary edema. Western blotting was used for quantifying protein levels of proinflammatory factors, nuclear factor kappa B (NF-κB), and NLR family pyrin domain containing 3 (NLRP3) signaling-associated proteins. Calmodulin 1 (Calm1) protein expression in murine lung tissues was evaluated by immunohistochemistry. The binding relation between miR-202-3p and Calm1 was assessed by luciferase reporter assay. The results showed that miR-202-3p was lowly expressed in the lung tissues of ARDS mice. Overexpressed miR-202-3p relieved LPS-induced edema, reduced proinflammatory factors, and inactivated NF-κB/NLRP3 signaling in murine lung tissues. Calm1 was targeted by miR-202-3p and displayed a high level of LPS-induced ARDS. In conclusion, miR-202-3p targets Calm1 and suppresses inflammation in LPS-induced ARDS, thereby inhibiting the pathogenesis of ARDS in a mouse model.

6-Gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition in LPS-provoked ARDS via RUNX1/NF-κB signaling pathway

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition play a central role in refractory hypoxemia in acute respiratory distress syndrome (ARDS), but it lacks effective drugs for prevention and treatment of this pathophysiology. Our previous experiment confirmed that RUNX1 promoted alveolar hypercoagulation and fibrinolytic inhibition through NF-κB pathway. Other studies demonstrated that 6-gingerol regulated inflammation and metabolism by inhibiting the NF-κB signaling pathway. We assume that 6-gingerol would ameliorate alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/ NF-κB pathway in LPS-induced ARDS.

METHODS

Rat ARDS model was replicated through LPS inhalation. Before LPS inhalation, the rats were intraperitoneally treated with different doses of 6-gingerol or the same volume of normal saline (NS) for 12 h, and then intratracheal inhalation of LPS for 24 h. In cell experiment, alveolar epithelial cell type II (AECII) was treated with 6-gingerol for 6 h and then with LPS for another 24 h. RUNX1 gene was down-regulated both in pulmonary tissue and in cells. Tissue factor (TF), plasminogen Activator Inhibitor 1(PAI-1) and thrombin were determined by Wester-blot (WB), qPCR or by enzyme-linked immunosorbent (ELISA). Lung injury score, pulmonary edema and pulmonary collagen III in rat were assessed. NF-κB pathway were also observed in vivo and in vitro. The direct binding capability of 6-gingerol to RUNX1 was confirmed by using Drug Affinity Responsive Target Stability test (DARTS).

RESULTS

6-gingerol dose-dependently attenuated LPS-induced lung injury and pulmonary edema. LPS administration caused excessive TF and PAI-1 expression both in pulmonary tissue and in AECII cell and a large amount of TF, PAI-1 and thrombin in bronchial alveolar lavage fluid (BALF), which all were effectively decreased by 6-gingerol treatment in a dose-dependent manner. The high collagen Ⅲ level in lung tissue provoked by LPS was significantly abated by 6-gingerol. 6-gingerol was seen to dramatically inhibit the LPS-stimulated activation of NF-κB pathway, indicated by decreases of p-p65/total p65, p-IKKβ/total IKKβ, and also to suppress the RUNX1 expression. RUNX1 gene knock down or RUNX1 inhibitor Ro5-3335 significantly enhanced the efficacies of 6-gingerol in vivo and in vitro, but RUNX1 over expression remarkably impaired the effects of 6-gingerol on TF, PAI-1 and on NF-κB pathway. DARTS result showed that 6-gingerol directly bond to RUNX1 molecules.

CONCLUSIONS

Our experimental data demonstrated that 6-gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/NF-κB pathway in LPS-induced ARDS. 6-gingerol is expected to be an effective drug in ARDS.

RUNX1 targeting AKT3 promotes alveolar hypercoagulation and fibrinolytic inhibition in LPS induced ARDS

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition are mainly responsible for massive alveolar fibrin deposition, which are closely related with refractory hypoxemia in acute respiratory distress syndrome (ARDS). Our previous study testified runt-related transcription factor (RUNX1) participated in the regulation of this pathophysiology in this syndrome, but the mechanism is unknown. We speculate that screening the downstream genes associated with RUNX1 will presumably help uncover the mechanism of RUNX1.

METHODS

Genes associated with RUNX1 were screened by CHIP-seq, among which the target gene was verified by Dual Luciferase experiment. Then the efficacy of the target gene on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS was explored in vivo as well as in vitro. Finally, whether the regulatory effects of RUNX1 on alveolar hypercoagulation and fibrinolytic in ARDS would be related with the screened target gene was also sufficiently explored.

RESULTS

Among these screened genes, AKT3 was verified to be the direct target gene of RUNX1. Results showed that AKT3 was highly expressed either in lung tissues of LPS-induced rat ARDS or in LPS-treated alveolar epithelia cell type II (AECII). Tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1) were increasingly expressed both in lung tissues of ARDS and in LPS-induced AECII, which were all significantly attenuated by down-regulation of AKT3. Inhibition of AKT3 gene obviously ameliorated the LPS-induced lung injury as well as the collagen I expression in ARDS. RUNX1 overexpression not only promoted the expressions of TF, PAI-1, but also boosted AKT3 expression in vitro. More importantly, the efficacy of RUNX1 on TF, PAI-1 were all effectively reversed by down-regulation of AKT3 gene.

CONCLUSION

AKT3 is an important target gene of RUNX1, through which RUNX1 exerted its regulatory role on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS. RUNX1/ATK3 signaling axis is expected to be a new target for the exploration of ARDS genesis and treatment.