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Background: It is well known that ventilation with high volume or pressure may damage healthy lungs or worsen injured lungs. Melatonin has been reported to be effective in animal models of acute lung injury. Melatonin exerts its beneficial effects by acting as a direct antioxidant and via melatonin receptor activation. However, it is not clear whether melatonin receptor agonist has a protective effect in ventilator-induced lung injury (VILI). Therefore, in this study, we determined whether ramelteon (a melatonin receptor agonist) can attenuate VILI and explore the possible mechanism for protection. Methods: VILI was induced by high tidal volume ventilation in a rat model. The rats were randomly allotted into the following groups: control, control+melatonin, control+ramelteon, control+luzindole, VILI, VILI+luzindole, VILI + melatonin, VILI + melatonin + luzindole (melatonin receptor antagonist), VILI + ramelteon, and VILI + ramelteon + luzindole (n = 6 per group). The role of interleukin-10 (IL-10) in the melatonin-or ramelteon-mediated protection against VILI was also investigated. Results: Ramelteon treatment markedly reduced lung edema, serum malondialdehyde levels, the concentration of inflammatory cytokines in bronchoalveolar lavage fluid (BALF), NF-κB activation, iNOS levels, and apoptosis in the lung tissue. Additionally, ramelteon treatment significantly increased heat shock protein 70 expression in the lung tissue and IL-10 levels in BALF. The protective effect of ramelteon was mitigated by the administration of luzindole or an anti-IL-10 antibody. Conclusions:Our results suggest that a melatonin receptor agonist has a protective effect against VILI, and its protective mechanism is based on the upregulation of IL-10 production.

Functional reduction of sodium-potassium-chloride co-transporter by genetic or pharmacologic treatment to inhibit sodium-potassium-chloride co-transporter resulted in lower severity of acute lung injury induced by ischemia-reperfusion. Sodium-potassium-chloride co-transporter may present a promising target for therapeutic interventions in a clinical setting.

With-no-lysine kinase 4 plays a crucial role in the regulation of epithelial ion channels and alveolar fluid clearance, mainly via phosphorylation and activation of STE20/SPS1-related proline/alanine-rich kinase and sodium-potassium-chloride cotransporter.

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BackgroundPatients with influenza complicated with pneumonia are at high risk of rapid progression to acute respiratory distress syndrome (ARDS). Prone positioning with longer duration and lung-protective strategies might reduce the mortality level in ARDS. The aim of this study is to investigate the survival predictors of prone positioning in patients with ARDS caused by influenza pneumonia.MethodsThis retrospective study was conducted by eight tertiary referral centers in Taiwan. From January 1 to March 31 in 2016, all of the patients in intensive care units with virology-proven influenza pneumonia were collected, while all of those patients with ARDS and receiving prone positioning were enrolled. Demographic data, laboratory examinations, management records, ventilator settings and clinical outcomes were collected for analysis.ResultsDuring the study period, 336 patients with severe influenza pneumonia were screened and 263 patients met the diagnosis of ARDS. Totally, 65 patients receiving prone positioning were included for analysis. The 60-day survivors had lower Acute Physiology and Chronic Health Evaluation (APACHE) II score, pneumonia severity index (PSI), creatinine level and lower rate of receiving renal replacement therapy than non-survivors (22.4 ± 8.5 vs. 29.2 ± 7.4, p = 0.003; 106.6 ± 40.9 vs. 135.3 ± 48.6, p = 0.019; 1.2 ± 0.9 mg/dL vs. 3.1 ± 3.6 mg/dL, p = 0.040; and 4% vs. 42%, p < 0.005). Multivariate Cox regression analysis identified PSI (hazard ratio 1.020, 95% confidence interval 1.009–1.032; p < 0.001), renal replacement therapy (hazard ratio 6.248, 95% confidence interval 2.245–17.389; p < 0.001), and increase in dynamic driving pressure (hazard ratio 1.372, 95% confidence interval 1.095–1.718; p = 0.006) which were independent predictors associated with 60-day mortality.ConclusionsIn the present study, in evaluating the effect of prone positioning in patients with influenza pneumonia-related ARDS, pneumonia severity index, renal replacement therapy and increase in dynamic driving pressure were associated with 60-day mortality in patients with influenza pneumonia-related ARDS receiving prone positioning.Electronic supplementary materialThe online version of this article (10.1186/s13613-018-0440-4) contains supplementary material, which is available to authorized users.

Background Axl is a cell surface receptor tyrosine kinase, and activation of the Axl attenuates inflammation induced by various stimuli. Growth arrest-specific 6 (Gas6) has high affinity for Axl receptor. The role of Gas6/Axl signaling in ischemia-reperfusion-induced acute lung injury (IR-ALI) has not been explored previously. We hypothesized that Gas6/Axl signaling regulates IR-induced alveolar inflammation via a pathway mediated by suppressor of cytokine signaling 3 (SOCS3). Methods IR-ALI was induced by producing 30 min of ischemia followed by 90 min of reperfusion in situ in an isolated and perfused rat lung model. The rats were randomly allotted to a control group and IR groups, which were treated with three different doses of Gas6. Mouse alveolar epithelium MLE-12 cells were cultured in control and hypoxia-reoxygenation (HR) conditions with or without Gas6 and Axl inhibitor R428 pretreatment. Results We found that Gas6 attenuated IR-induced lung edema, the production of proinflammatory cytokines in perfusates, and the severity of ALI ex vivo. IR down-regulated SOCS3 expression and up-regulated NF-κB, and Gas6 restored this process. In the model of MLE-12 cells with HR, Gas6 suppressed the activation of TRAF6 and NF-κB by up-regulating SOCS3. Axl expression of alveolar epithelium was suppressed in IR-ALI but Gas6 restored phosphorylation of Axl. The anti-inflammatory effect of Gas6 was antagonized by R428, which highlighted that phosphorylation of Axl mediated the protective role of Gas6 in IR-ALI. Conclusions Gas6 up-regulates phosphorylation of Axl on alveolar epithelium in IR-ALI. The Gas6/Axl signaling activates the SOCS3-mediated pathway and attenuates IR-related inflammation and injury.

Our study demonstrates that NASD patients are at a higher risk of developing female infertility.