Pleiotropic role of endoplasmic reticulum stress in the protection of psoralidin against sepsis-associated encephalopathy.

Sepsis-associated encephalopathy (SAE) is a severe complication that affects the central nervous system and is a leading cause of increased morbidity and mortality in intensive care units. Psoralidin (PSO), a coumarin compound isolated from the traditional Chinese medicine Psoralea corylifolia L., can penetrate the blood-brain barrier and has various pharmacological activities, including anti-inflammation, anti-oxidation and anti-depression. This study aims to explore whether PSO alleviates SAE and delve into the underlying mechanisms. We found that PSO treatment significantly reduced sepsis scores, aspartate transaminase (AST) and aspartate transaminase (LDH), while increased anal temperature and neurological scores in CLP-injured mice. Moreover, PSO treatment ameliorated sepsis-associated cognitive impairment, mood, anxiety disorders, inhibited inflammatory responses, as well as attenuated endoplasmic reticulum stress (ERS). These results were also validated in vitro experiments, PSO treatment reduced ROS, inflammation response, and attenuated ERS in LPS-injured N2a cells. Importantly, tunicamycin (TUN), as ERS agonist, significantly reversed the protective effect of PSO on LPS-injured N2a cells, as evidenced by increased expression levels of IL-6, NLRP3, CHOP, and ATF6. Likewise, ATF6 overexpression also reversed the protective effect of PSO. In conclusion, these results confirmed that PSO has a protective effect on SAE, which was largely attributed to neuroinflammation and ERS. These findings provide new insights into the neuroprotective role of PSO and suggest that PSO is a new therapeutic intervention of SAE.

Effect of a self-developed fixation device on preventing endotracheal intubation-related pressure injury: a randomised controlled trial.

OBJECTIVE: To evaluate the effects of our self-developed endotracheal tube fixation device in mechanically ventilated patients. METHODS: In a dual-centre randomised controlled trial, patients who were expected to require mechanical ventilation for over 48 h were assigned to the observation group (using self-developed device) or the control group (using the traditional device). The primary endpoint was the incidence of endotracheal intubation-related pressure injury (EIRPI). RESULTS: Fifty-one patients in the observation group and 54 patients in the control group were analysed. The incidence of EIRPI was 7.8% in the observation group and 33.3% in the control group (p = 0.001). Lip pressure injury (PI) occurred in 0 versus 14 (25.9%) patients in the observation versus control groups (p < 0.001). Both oral-mucosal and facial PIs were similar between the two groups. CONCLUSIONS: The use of the novel device reduced the incidence of EIRPI, especially lip PI. Trial registration Chinese Clinical Trial Registry ChiCTR2300078132. Registered on 29 November 2023.

Epigenetic regulation of ferroptosis by H2B monoubiquitination and p53.

Monoubiquitination of histone H2B on lysine 120 (H2Bub1) is an epigenetic mark generally associated with transcriptional activation, yet the global functions of H2Bub1 remain poorly understood. Ferroptosis is a form of non-apoptotic cell death characterized by the iron-dependent overproduction of lipid hydroperoxides, which can be inhibited by the antioxidant activity of the solute carrier family member 11 (SLC7A11/xCT), a component of the cystine/glutamate antiporter. Whether nuclear events participate in the regulation of ferroptosis is largely unknown. Here, we show that the levels of H2Bub1 are decreased during erastin-induced ferroptosis and that loss of H2Bub1 increases the cellular sensitivity to ferroptosis. H2Bub1 epigenetically activates the expression of SLC7A11. Additionally, we show that the tumor suppressor p53 negatively regulates H2Bub1 levels independently of p53's transcription factor activity by promoting the nuclear translocation of the deubiquitinase USP7. Moreover, our studies reveal that p53 decreases H2Bub1 occupancy on the SLC7A11 gene regulatory region and represses the expression of SLC7A11 during erastin treatment. These data not only suggest a noncanonical role of p53 in chromatin regulation but also link p53 to ferroptosis via an H2Bub1-mediated epigenetic pathway. Overall, our work uncovers a previously unappreciated epigenetic mechanism for the regulation of ferroptosis.

Inhibition of lipolysis by mercaptoacetate and etomoxir specifically sensitize drug-resistant lung adenocarcinoma cell to paclitaxel.

Chemoresistance is a major cause of treatment failure in patients with lung cancer. Although the extensive efforts have been made in overcoming chemoresistance, the underlying mechanisms are still elusive. Cancer cells reprogram cellular metabolism to satisfy the demands of malignant phenotype. To reveal roles of cancer metabolism in regulating chemoresistance, we profiled the metabolic characteristics in paclitaxel-resistant lung cancer cells by flux assay. Glucose and oleate metabolism were significantly different between resistant and non-resistant cells. In addition, targeting metabolism as a strategy to overcome drug resistance was investigated using specific metabolic inhibitors. Inhibition of glycolysis and oxidative phosphorylation by 2-deoxyglucose and malonate, respectively, potentiated the effects of paclitaxel on nonresistant lung adenocarcinoma cells but not paclitaxel-resistant cells. By contrast, inhibition of lipolysis by mercaptoacetate or etomoxir synergistically inhibited drug-resistant lung adenocarcinoma cell proliferation. We conclude that lipolysis inhibition potentially be a therapeutic strategy to overcome drug resistance in lung cancer.