Bcl-2 Rabbit Polyclonal Antibody

Background: The objective of this study is to delineate the differential gene expression patterns of neutrophils in bronchoalveolar lavage fluid (BALF) from patients with sepsis and those experiencing progression to sepsis-induced acute respiratory distress syndrome (SI-ARDS). Additionally, we aim to comprehensively profile the transcriptomic landscape of neutrophils in BALF from patients with sepsis and SI-ARDS, particularly focusing on cases caused by specific bacterial pathogens. Methods: Patients with confirmed sepsis ( n = 14) or SI-ARDS ( n = 11) were recruited. Besides, a control group consisting of patients with unrelated diseases ( n = 7) who required bronchoscopy was also included (cohort 1). We collected the neutrophils in BALF from participants in cohort 1. To validate the identified differentially expressed genes (DEGs) and evaluate neutrophil apoptosis, an additional cohort (cohort 2) was recruited, consisting of 5 healthy controls, 10 patients with sepsis, and 10 patients with SI-ARDS. Peripheral blood neutrophils were collected from participants in cohort 2 for further analysis. DEGs between SI-ARDS patients and controls, sepsis patients and controls, as well as SI-ARDS patients and sepsis patients were identified. And, publicly available datasets were downloaded to compare with local results. Additionally, the DEGs were also identified between patients infected with drug-resistant Klebsiella pneumoniae and those infected with other bacterial pathogens. Furthermore, a third cohort (cohort 3) consisting of 57 sepsis patients and 46 SI-ARDS patients was recruited for investigating the prognostic significance of neutrophils in SI-ARDS. Results: In cohort 1, 8/14 of the septic patients and 6/11 of the SI-ARDS patients were affected by drug-resistant Klebsiella pneumonia. There were 9921 DEGs between sepsis patients and controls, 10,252 DEGs between SI-ARDS patients and controls, and 24 DEGs between SI-ARDS and sepsis patients in neutrophils from BALF. Notably, fatty acid-binding pro­tein 4 (FABP4) exhibited significant downregulation in SI-ARDS patients. In cohort 2, peripheral blood analysis confirmed consistent trends, demonstrating that FABP4 expression was decreased, which contributed to the attenuation of neutrophil apoptosis. And FABP4 inhibitor-induced apoptosis resistance was reversed by a phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) inhibitor. Furthermore, survival analysis revealed that SI-ARDS patients with low levels of neutrophil FABP4 expression exhibited poor survival. Additionally, 520 overlapping DEGs were identified between the sepsis and control group comparisons and the SI-ARDS and sepsis group comparisons. Among these overlapping DEGs, 85% were downregulated, predominantly targeting immune-related pathways, whereas a smaller subset was upregulated, mainly associated with metabolism. DEGs in neutrophils in BALF of SI-ARDS and controls notably overlapped with those in neutrophils in peripheral blood. Importantly, DEGs in sepsis/SI-ARDS caused by drug-resistant Klebsiella pneumoniae differed from DEGs in sepsis/SI-ARDS caused by other bacteria. Additionally, FABP4 expression consistently decreased, attenuating neutrophil apoptosis. Conclusions: The downregulation of FABP4 in neutrophils was found to inhibit apoptosis through the activation of the PI3K/AKT signaling pathway. Importantly, the expression level of FABP4 in neutrophil emerged as a prognostic indicator for sepsis and SI-ARDS patients, suggesting its potential utility in clinical decision-making to address the challenges posed by this condition.

Background Ferroptosis plays a key role in the development of chronic obstructive pulmonary disease (COPD). Whether ginsenoside Rg1 improves cigarette smoke-induced COPD or whether ginsenoside Rg1 improves COPD by inhibiting ferroptosis remains unknown. Methods BEAS-2B cells were exposed to cigarette solution (CSE) for 24 hours and treated with ginsenoside Rg1, the ferroptosis inhibitor Fer-1, and the PERK inhibitor GSK. Cell viability, endoplasmic reticulum stress, mitochondrial morphology, membrane potential, reactive oxygen species (ROS), iron levels, and the expression of related proteins were detected using corresponding methods. A COPD mouse model was constructed using cigarette smoke (CS). Ginsenoside Rg1 and GSK were administered via tube feeding 15 days after successful modeling. Mouse lung tissues were evaluated by HE staining. The expression of inflammatory markers, ROS, iron content, and related proteins was detected using corresponding methods. Results The results demonstrated that in the CSE-exposed BEAS-2B cell model and CS-induced mouse COPD model, the expression levels of endoplasmic reticulum stress (ERS)-related factors such as GRP78 were increased, while those of the antioxidant markers GPX4 and GSH were significantly decreased. Ginsenoside Rg1 improved emphysema and inflammation by inhibiting ferroptosis in vivo and in vitro. Using a PERK inhibitor, we found that ginsenoside Rg1 inhibited ferroptosis in vivo and in vitro by regulating ERS. Conclusion This study showed that ginsenoside Rg1 alleviates cigarette smoke-induced COPD by regulating the PERK/ATF4 axis to inhibit ERS and ferroptosis.