Dataset Information

The dynamic changes in autophagy activity and its role in lung injury after deep hypothermic circulatory arrest.

ABSTRACT: Deep hypothermic circulatory arrest (DHCA) can cause acute lung injury (ALI), and its pathogenesis mimics ischaemia/reperfusion (I/R) injury. Autophagy is also involved in lung I/R injury. The present study aimed to elucidate whether DHCA induces natural autophagy activation and its role in DHCA-mediated lung injury. Here, rats were randomly assigned to the Sham or DHCA group. The sham group (n = 5) only received anaesthesia and air intubation. DHCA group rats underwent cardiopulmonary bypass (CPB) followed by the DHCA procedure. The rats were then sacrificed at 3, 6 and 24 h after the DHCA procedure (n = 5) to measure lung injury and autophagy activity. Chloroquine (CQ) was delivered to evaluate autophagic flux. DHCA caused lung injury, which was prominent 3-6 h after DHCA, as confirmed by histological examination and inflammatory cytokine quantification. Lung injury subsided at 24 h. Autophagy was suppressed 3 h but was exaggerated at 6 h. At both time points, autophagic flux appeared uninterrupted. To further assess the role of autophagy in DHCA-mediated lung injury, the autophagy inducer rapamycin and its inhibitor 3-methyladenine (3-MA) were applied, and lung injury was reassessed. When rapamycin was administered at an early time point, lung injury worsened, whereas administration of 3-MA at a late time point ameliorated lung injury, indicating that autophagy contributed to lung injury after DHCA. Our study presents a time course of lung injury following DHCA. Autophagy showed adaptive yet protective suppression 3 h after DHCA, as induction of autophagy caused worsening of lung tissue. In contrast, autophagy was exaggerated 6 h after DHCA, and autophagy inhibition attenuated DHCA-mediated lung injury.

SUBMITTER: Kong M

PROVIDER: S-EPMC8831962 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The dynamic changes in autophagy activity and its role in lung injury after deep hypothermic circulatory arrest.

Kong Minjian M Wei Dongdong D Li Xuebiao X Zhu Xian X Hong Ze Z Ni Ming M Wang Yifan Y Dong Aiqiang A

Journal of cellular and molecular medicine 20220111 4

Deep hypothermic circulatory arrest (DHCA) can cause acute lung injury (ALI), and its pathogenesis mimics ischaemia/reperfusion (I/R) injury. Autophagy is also involved in lung I/R injury. The present study aimed to elucidate whether DHCA induces natural autophagy activation and its role in DHCA-mediated lung injury. Here, rats were randomly assigned to the Sham or DHCA group. The sham group (n = 5) only received anaesthesia and air intubation. DHCA group rats underwent cardiopulmonary bypass (C ...[more]

PMID: 35014165

Similar Datasets

Project description:Cardiac surgery, especially when employing cardiopulmonary bypass and deep hypothermic circulatory arrest, is associated with systemic inflammatory responses that significantly affect morbidity and mortality. Intestinal perfusion abnormalities have been implicated in such responses, but the mechanisms linking local injury and systemic inflammation remain unclear. Intestinal mast cells are specialized immune cells that secrete various preformed effectors in response to cellular stress. We hypothesized that mast cells are activated in a microenvironment shaped by intestinal ischemia/reperfusion, and investigated local and systemic consequences.Rat model of deep hypothermic circulatory arrest.University research laboratory.Twelve- to 14-week-old male Sprague-Dawley rats.Rats were anesthetized and cooled to 16°C to 18°C on cardiopulmonary bypass before instituting deep hypothermic circulatory arrest for 45 minutes. Specimens were harvested following rewarming and 2 hours of recovery.Significant intestinal barrier disruption was found, together with macro- and microscopic evidence of ischemia/reperfusion injury in ileum and colon, but not in the lungs or kidneys. Immunofluorescence and toluidine blue staining revealed increased numbers of mast cells and their activation in the gut. In animals pretreated with the mast cell stabilizer, cromolyn sodium, mast cell degranulation was blocked, and intestinal morphology and barrier function were preserved following deep hypothermic circulatory arrest. Furthermore, cromolyn sodium treatment was associated with reduced intestinal neutrophil influx and blunted systemic release of proinflammatory cytokines.Our data provide primary evidence that intestinal ischemia/reperfusion is a leading pathophysiologic process in a rat model of deep hypothermic circulatory arrest, and that intestinal injury, and local and systemic inflammatory responses are critically dependent on mast cell activation. This identifies intestinal mast cells as central players in deep hypothermic circulatory arrest-associated responses, and opens novel therapeutic possibilities for patients undergoing this procedure.

Project description:Resolution agonists, including lipid mediators and peptides such as annexin A1 (ANXA1), are providing novel approaches to treat inflammatory conditions. Surgical trauma exerts a significant burden on the immune system that can affect and impair multiple organs. Perioperative cerebral injury after cardiac surgery is associated with significant adverse neurological outcomes such as delirium and postoperative cognitive dysfunction. Using a clinically relevant rat model of cardiopulmonary bypass (CPB) with deep hypothermic circulatory arrest (DHCA), we tested the pro-resolving effects of a novel bioactive ANXA1 tripeptide (ANXA1sp) on neuroinflammation and cognition. Male rats underwent 2 h CPB with 1 h DHCA at 18°C, and received vehicle or ANXA1sp followed by timed reperfusion up to postoperative day 7. Immortalized murine microglial cell line BV2 were treated with vehicle or ANXA1sp and subjected to 2 h oxygen-glucose deprivation followed by timed reoxygenation. Microglial activation, cell death, neuroinflammation, and NF-κB activation were assessed in tissue samples and cell cultures. Rats exposed to CPB and DHCA had evident neuroinflammation in various brain areas. However, in ANXA1sp-treated rats, microglial activation and cell death (apoptosis and necrosis) were reduced at 24 h and 7 days after surgery. This was associated with a reduction in key pro-inflammatory cytokines due to inhibition of NF-κB activation in the brain and systemically. Treated rats also had improved neurologic scores and shorter latency in the Morris water maze. In BV2 cells treated with ANXA1sp, similar protective effects were observed including decreased pro-inflammatory cytokines and cell death. Notably, we also found increased expression of ANXA1, which binds to NF-κB p65 and thereby inhibits its transcriptional activity. Our findings provide evidence that treatment with a novel pro-resolving ANXA1 tripeptide is neuroprotective after cardiac surgery in rats by attenuating neuroinflammation and may prevent postoperative neurologic complications.

Dataset Information

The dynamic changes in autophagy activity and its role in lung injury after deep hypothermic circulatory arrest.

Publications

The dynamic changes in autophagy activity and its role in lung injury after deep hypothermic circulatory arrest.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets