Serum 8-Hydroxydeoxyguanosine Is a Potential Indicator for the Severity and Prognosis in Patients with Community-Acquired Pneumonia: A Prospective Cohort Study.

Previous studies have demonstrated that 8-hydroxydeoxyguanosine (8-OHdG) exerted key roles in various pulmonary diseases, but the evidence for its role in community-acquired pneumonia (CAP) was lacking. The goal of this research was to evaluate the correlations of serum 8-OHdG with the severity and prognosis among patients with CAP through a prospective cohort study. A total of 239 patients with CAP and 239 healthy participants were enrolled. Fasting blood samples were collected. 8-OHdG and inflammatory cytokines were measured by ELISA. On admission, serum 8-OHdG was significantly increased in patients with CAP compared with control subjects. Besides, serum 8-OHdG was incrementally increased in line with CAP severity scores. Pearson correlative analysis found that serum 8-OHdG was correlated with clinical characteristics and inflammatory cytokines in patients with CAP. Linear and logistic regression analysis showed that serum 8-OHdG was positively associated with CAP severity scores. Furthermore, the prognostic outcomes were tracked. Higher serum 8-OHdG on admission increased the risks for intensive care unit admission, mechanical ventilation, vasoactive agent usage, death, and longer hospital stay among patients with CAP. Serum 8-OHdG combination with confusion, respiratory rate, blood pressure, and age ≥65 y or pneumonia severity index had stronger predictive powers for death than single 8-OHdG, CAP severity scores, or several inflammatory cytokines in patients with CAP. These results indicated that serum 8-OHdG is positively associated with the severity and poor prognosis in patients with CAP, demonstrating that 8-OHdG may be involved in the pathophysiology process of CAP.

Therapeutic Effects of SRT2104 on Lung Injury in Rats with Emphysema via Reduction of Type II Alveolar Epithelial Cell Senescence.

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent and severe diseases worldwide with high societal and health care costs. The pathogenesis of COPD is very complicated, and no curative treatment is available. Cellular senescence promotes the development of COPD. Type II alveolar epithelial cells (AECII) play a momentous role in lung tissue repair and maintenance of alveolar homeostasis. Sirtuin 1 (SIRT1), an antiaging molecule involved in the response to chronic inflammation and oxidative stress, regulates many pathophysiological changes including stress resistance, apoptosis, inflammation, and cellular senescence. This study aimed to investigate whether the pharmacological SIRT1 activator SRT2104 protects against AECII senescence in rats with emphysema. Our findings confirmed that SRT2104 administration reduced the pathological characteristics of emphysema and improved lung function parameters, including pulmonary resistance, pulmonary dynamic compliance, and peak expiratory flow. Moreover, SRT2104 treatment upregulated the expression of surfactant proteins A and C, SIRT1, and forkhead box O 3a (FoxO3a), decreased senescence-associated-ß-galactosidase (SA-ß-gal) activity, increased SIRT1 deacetylase activity, and downregulated the levels of p53 and p21. Therefore, SRT2104 administration protected against AECII senescence in rats with emphysema via SIRT1/FoxO3a and SIRT1/p53 signaling pathways and may provide a novel potential therapeutic strategy for COPD.

Clinical and molecular epidemiology of enterovirus D68 from 2013 to 2020 in Shanghai.

Enterovirus D68 (EV-D68) is an emerging pathogen that has caused outbreaks of severe respiratory disease worldwide, especially in children. We aim to investigate the prevalence and genetic characteristics of EV-D68 in children from Shanghai. Nasopharyngeal swab or bronchoalveolar lavage fluid samples collected from children hospitalized with community-acquired pneumonia were screened for EV-D68. Nine of 3997 samples were EV-D68-positive. Seven of nine positive samples were sequenced and submitted to GenBank. Based on partial polyprotein gene (3D) or complete sequence analysis, we found the seven strains belong to different clades and subclades, including three D1 (detected in 2013 and 2014), one D2 (2013), one D3 (2019), and two B3 (2014 and 2018). Overall, we show different clades and subclades of EV-D68 spread with low positive rates (0.2%) among children in Shanghai between 2013 and 2020. Amino acid mutations were found in the epitopes of the VP1 BC and DE loops and C-terminus; similarity analysis provided evidence for recombination as an important mechanism of genomic diversification. Both single nucleotide mutations and recombination play a role in evolution of EV-D68. Genetic instability within these clinical strains may indicate large outbreaks could occur following cumulative mutations.

Association Between Obstructive Sleep Apnea-Hypopnea Syndrome and Outcomes in Patients With Myocardial Infarction in the Absence of Obstructive Coronary Artery Disease.

Background and Aims: Myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) occurs in 5-10% of all patients with acute myocardial infarction. Obstructive sleep apnea-hypopnea syndrome (OSAHS) is linked to increased cardiovascular morbidity and mortality, but the relationship of OSAHS and outcomes in patients with MINOCA remains unknown. We aimed to evaluate the association between OSAHS and clinical outcomes in patients with MINOCA. Methods: Between January 2015 and December 2016, we carried out a consecutive cohort study of 583 patients with MINOCA and followed them up for 3 years. An apnea-hypopnea index of ≥ 15 events per hour recorded by polysomnography was defined as the diagnostic criterion for OSAHS. The primary end point was all-cause mortality, and the second end point was major adverse cardiovascular or cerebrovascular events (MACCE), a composite of cardiac death, non-fatal myocardial infarction, heart failure, cardiovascular-related rehospitalization, and stroke. Results: All-cause mortality happened in 69 patients and MACCE occurred in 113 patients during the 3-year follow-up. Kaplan-Meier survival curves indicated the significant relationship of OSAHS with all-cause mortality (log-rank P = 0.012) and MACCE (log-rank P = 0.002). Multivariate Cox regression analysis indicated OSAHS as an independent predictor of all-cause mortality and MACCE [adjusted hazard ratio: 1.706; 95% confidence interval (CI): 1.286-2.423; P = 0.008; and adjusted hazard ratio: 1.733; 95% CI: 1.201-2.389; P < 0.001; respectively], independent of age, sex, cardiovascular risk factors and discharge medications. Conclusions: OSAHS is independently associated with increased risk of all-cause mortality and MACCE in patients with MINOCA. Intervention and treatment should be considered to alleviate OSAHS-associated risk.

Phenylbutyric acid inhibits epithelial-mesenchymal transition during bleomycin-induced lung fibrosis.

A recent report showed that unfolded protein response (UPR) signaling was activated during bleomycin (BLM)-induced pulmonary fibrosis. Phenylbutyric acid (PBA) is an endoplasmic reticulum (ER) chemical chaperone that inhibits the UPR signaling. The present study investigated the effects of PBA on BLM-induced epithelial-mesenchymal transition (EMT) and pulmonary fibrosis. For induction of pulmonary fibrosis, all mice except controls were intratracheally injected with a single dose of BLM (3.0mg/kg). In PBA+BLM group, mice were intraperitoneally injected with PBA (150mg/kg) daily. Three weeks after BLM injection, EMT was measured and pulmonary fibrosis was evaluated. BLM-induced pulmonary UPR activation was inhibited by PBA. Moreover, BLM-induced pulmonary nuclear factor kappa B (NF-κB) p65 activation was blocked by PBA. In addition, BLM-induced up-regulation of pulmonary inflammatory cytokines was repressed by PBA. Further analysis showed that BLM-induced α-smooth muscle actin (α-SMA), a marker for EMT, was significantly attenuated by PBA. Moreover, BLM-induced pulmonary collagen (Col1α1 and Col1α2) was obviously inhibited by PBA. Importantly, BLM-induced pulmonary fibrosis, as determined using Sirius red staining, was obviously alleviated by PBA. Taken together, these results suggest that PBA alleviates ER stress-mediated EMT in the pathogenesis of BLM-induced pulmonary fibrosis.

Melatonin inhibits endoplasmic reticulum stress and epithelial-mesenchymal transition during bleomycin-induced pulmonary fibrosis in mice.

Several reports indicate that melatonin alleviates bleomycin (BLM)-induced pulmonary fibrosis in rodent animals. Nevertheless, the exact mechanism remains obscure. The present study investigated the effects of melatonin on endoplasmic reticulum (ER) stress and epithelial-mesenchymal transition (EMT) during BLM-induced lung fibrosis. For the induction of pulmonary fibrosis, mice were intratracheally injected with a single dose of BLM (5.0 mg/kg). Some mice were intraperitoneally injected with melatonin (5 mg/kg) daily for a period of 3 wk. Twenty-one days after BLM injection, lung fibrosis was evaluated. As expected, melatonin significantly alleviated BLM-induced pulmonary fibrosis, as evidenced by Sirius red staining. Moreover, melatonin significantly attenuated BLM-induced EMT to myofibroblasts, as determined by its repression of α-SMA expression. Further analysis showed that melatonin markedly attenuated BLM-induced GRP78 up-regulation and elevation of the cleaved ATF6 in the lungs. Moreover, melatonin obviously attenuated BLM-induced activation of pulmonary eIF2α, a downstream target of the PERK pathway. Finally, melatonin repressed BLM-induced pulmonary IRE1α phosphorylation. Correspondingly, melatonin inhibited BLM-induced activation of XBP-1 and JNK, two downstream targets of the IRE1 pathway. Taken together, these results suggest that melatonin alleviates ER stress and ER stress-mediated EMT in the process of BLM-induced pulmonary fibrosis.