Intracellular ion channel inositol 1,4,5-triphosphate receptor (IP3R1) releases Ca2+ from endoplasmic reticulum. The disturbance of IP3R1 is related to several neurodegenerative diseases. This study investigated the mechanism of IP3R1 in myocardial ischemia/reperfusion (MI/R). After MI/R modeling, IP3R1 expression was silenced in myocardium of MI/R rats to explore its role in the concentration of myocardial enzymes, infarct area, Ca2+ level, NLRP3/Caspase-1, and pyroptosis markers and inflammatory factors. The adult rat cardiomyocytes were isolated and cultured to establish hypoxia/reperfusion (H/R) cell model. The expression of IP3R1 was downregulated or ERP44 was overexpressed in H/R-induced cells. Nifedipine D6 was added to H/R-induced cells to block Ca2+ channel or Nigericin was added to activate NLRP3. IP3R1 was highly expressed in myocardium of MI/R rats, and silencing IP3R1 alleviated MI/R injury, reduced Ca2+ overload, inflammation and pyroptosis in MI/R rats, and H/R-induced cells. The binding of ERP44 to IP3R1 inhibited Ca2+ overload, alleviated cardiomyocyte inflammation, and pyroptosis. The increase of intracellular Ca2+ level caused H/R-induced cardiomyocyte pyroptosis through the NLRP3/Caspase-1 pathway. Activation of NLRP3 pathway reversed the protection of IP3R1 inhibition/ERP44 overexpression/Nifedipine D6 on H/R-induced cells. Overall, ERP44 binding to IP3R1 inhibits Ca2+ overload, thus alleviating pyroptosis and MI/R injury.
Introduction Catheter management strategies for suspected catheter-related bloodstream infection (CRBSI) remain a major challenge in intensive care units (ICUs). The objective of this study was to determine the incidence, risk factors, and mortality attributable to CRBSIs in those patients. Methods A population-based surveillance on suspected CRBSI was conducted from 2009 to 2018 in a tertiary care hospital in China. We used the results of catheter tip culture to identify patients with suspected CRBSIs. Demographics, systemic inflammatory response syndrome (SIRS) criteria, interventions, and microorganism culture results were analysed and compared between patients with and without confirmed CRBSIs. Univariate and multivariate analyses identified the risk factors for CRBSIs, and attributable mortality was evaluated with a time-varying Cox proportional hazard model. Results In total, 686 patients with 795 episodes of suspected CRBSIs were included; 19.2% (153/795) episodes were confirmed as CRBSIs, and 17.4% (119/686) patients died within 30 days. The multifactor model shows that CRBSIs were associated with fever, hypotension, acute respiratory distress syndrome, hyperglycaemia and the use of continuous renal replacement therapy. The AUC was 77.0% (95% CI 73.3%–80.7%). The population attributable mortality fraction of CRBSI in patients was 18.2%, and mortality rate did not differ significantly between patients with and without CRBSIs (95% CI 0.464–1.279, P = 0.312). Conclusions This initial model based on the SIRS criteria is relatively better at identifying patients with CRBSI but only in domains of the sensitivity. There were no significant differences in attributable mortality due to CRBSI and other causes in patients with suspected CRBSI, which prompt catheter removal and re-insertion of new catheter may not benefit patients with suspected CRBSIs. Trial Registration China Clinical Trials Registration number; ChiCTR1900022175. Supplementary Information The online version contains supplementary material available at 10.1007/s40121-021-00429-3.
Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a ligand-binding nuclear receptor, and its activation plays a prominent role in regulating the inflammatory response. Therefore, PPAR-γ has been suggested as a candidate gene for sepsis. In the present study, we investigated the association between the Pro12Ala polymorphism of PPAR-γ and sepsis in a Han Chinese population. A total of 308 patients with sepsis and 345 healthy controls were enrolled in this study. Genotyping was performed using the polymerase chain reaction-ligation detection reaction (PCR-LDR) method. No significant differences were detected in the allele and genotype distributions of the PPAR-γ Pro12Ala SNP between septic patients and controls (P = 0.622 for genotype; P = 0.629 for allele). However, stratification by subtypes (sepsis, septic shock, and severe sepsis) revealed a statistically significant difference in the frequency of the Ala allele and Ala-carrier genotype between the patients with the sepsis subtype and the healthy controls (P = 0.014 for allele and P = 0.012, for genotype). Moreover, significant differences were found in the frequency of the Ala allele and genotype between the sepsis survivors and nonsurvivors (all P = 0.002). In the survivors, the PPAR-γ Pro12Ala genotype was significantly associated with decreased disease severity and recovery time (all P < 0.001). Thus, genetic polymorphism is thought to play a role in the development and outcome of sepsis.
Evidence reveals that propofol protects cells via suppressing excessive autophagy induced by hypoxia/reoxygenation (H/R). Previously, we found in a genome-wide microRNA profile analysis that several autophagy-related microRNAs were significantly altered during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH), but how these microRNAs work in P-PostH is still largely unknown. Here, we found that one of these microRNAs, microRNA-30b (miR-30b), in human umbilical vein endothelial cells (HUVECs) was downregulated by H/R treatment but significantly upregulated by 100 M propofol after H/R treatment. miR-30b showed similar changes in open heart surgery patients. By dual-luciferase assay, we found that Beclin-1 is the direct target of miR-30b. This conclusion was also supported by knockdown or overexpression of miR-30b. Further studies showed that miR-30b inhibited H/R-induced autophagy activation. Overexpression or knockdown of miR-30b regulated autophagy-related protein gene expression in vitro. To clarify the specific role of propofol in the inhibition of autophagy and distinguish the induction of autophagy from the damage of autophagy flux, we used bafilomycin A1. LC3-II levels were decreased in the group treated with propofol combined with bafilomycin A1 compared with the group treated with bafilomycin A1 alone after hypoxia and reoxygenation. Moreover, HUVECs transfected with Ad-mCherry-GFP-LC3b confirmed the inhibitory effect of miR-30b on autophagy flux. Finally, we found that miR-30b is able to increase the cellular viability under the H/R condition, partially mimicking the protective effect of propofol which suppressed autophagy via enhancing miR-30b and targeting Beclin-1. Therefore, we concluded that propofol upregulates miR-30b to repress excessive autophagy via targeting Beclin-1 under H/R condition. Thus, our results revealed a novel mechanism of the protective role of propofol during anesthesia. Clinical Trial Registration Number. This trial is registered with ChiCTR-IPR-14005470. The name of the trial register: Propofol Upregulates MicroRNA-30b to Repress Beclin-1 and Inhibits Excessive Autophagy and Apoptosis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.