The Mechanism of lncRNA NEAT1 in Alleviating Acute Respiratory Distress Syndrome Through miR-27b Regulated Nrf2 Pathway

Capital Medical University

Status: Unknown

Conditions: Inflammation; Acute Respiratory Distress Syndrome

Treatments: Other: no intervention

Study type: Observational

Funder types: Other

Identifiers

NCT04937855

81970067

Details and patient eligibility

About

The acute respiratory distress syndrome, formerly known as the acute lung injury (ARDS/ALI), is a critical illness with high mortality due to the lack of effective treatment. The pathogenesis of ARDS/ALI has not been fully elucidated. Nuclear factor E2-related factor 2 (Nrf2) plays a key role in regulating lung inflammation and oxidative stress which are closely related to lung injury in ARDS/ALI, but its regulatory mechanism remains unclear. The investigator's provious study shown that microRNA-27b (miR-27b) downregulated Nrf2 to aggravate lung inflammation and histological injury. Furthermore, in lipopolysaccharide (LPS)-induced cell (J774A.1) inflammation model, miR-27b was upregulated while the long non-coding RNA (lncRNA) NEAT1 was downregulated, the putative binding sites of lncRNA NEAT1 and miR-27b were successfully predicted by bioinformatics approach. Thus, the investigators propose that NEAT1 plays as a competing endogenous RNA (ceRNA) to adsorb miR-27b and liberate Nrf2, therefore, to attenuate lung inflammation and related lung injury in ARDS/ALI. This project aims to explore the role of the lncRNA NEAT1/ mir-27b /Nrf2 signal axis in the development and treatment of ARDS/ALI in patients, as well as in LPS-induced ALI animal and cell models by using bioinformatics, molecular biology, histomorphology and clinical phenotype approaches, and to clarify the new mechanism in ARDS/ALI development and to provide new therapeutic targets.

Full description

Collect blood and BALF from 400 ARDS patients at different time (at check-in, 24, 48 and 72 h after check-in the hospital) and 25 gender and age matching healthy controls. Use RT-PCR to detect the expression of lncRNA NEAT1、miR-27b and Nrf2 in blood and BALF of ARDS patients and health controls. The expressions of inflammatory and oxidative stress associated factors (NLRP3、NF-κB-P65、 p-P65、IκB、p-IκB、HO-1、NQO1、caspase-1、IL-1β、IL-6、IL-18、TNF-α) will be detected by western blot、ELISA and RT-PCR. Moreover, flow cytometry will be adopted to measure the numbers and kinds of cells in BALF. Then, analyze the differences of the expressions of lncRNA NEAT1、miR-27b and Nrf2 in the groups. To explore the correlation of expressions of lncRNA NEAT1、miR-27b and Nrf2 with inflammation and oxidative stress in the groups. Finally, to declare the relative of lncRNA NEAT1、miR-27b and Nrf2 with the time of mechanical ventilation, severity and mortality in 28 days of ARDS patients.

Enrollment: 425 estimated patients

Sex: All

Ages: 18 to 70 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

We included patients with acute respiratory distress according to 2012 ARDS Berlin new definition (Acute Respiratory Distress Syndrome: The Berlin Definition. JAMA, 2012, 307(23):2526).

• Acute or progressive dyspnea within 1 week with identify cause;
• Chest radiograph/chest CT showed double lung infiltration, which could not be fully explained by pleural effusion, atelectasis, or nodules;
• Respiratory failure cannot be fully explained by heart failure and fluid overload;
• Hypoxemia, partial pressure of oxygen in arterial blood (PaO2)/oxygen fraction in air (FIO2) <150 mm Hg under PEEP ≥5 cm H2O, (mild ARDS: 200mmHg<PaO2/FiO2≤300mmHg, moderate ARDS: 100mmHg<PaO2/FiO2≤200mmHg, severe ARDS: PaO2/FiO2≤100mmHg);
• 18~70 years old;
• Agree to participate in the trial, and sign the informed consent.

Exclusion criteria

• Age less than 18 years old;
• Time of hospital stay <24 h;
• Pregnancy;
• Using V-V ECOM;
• Cardiac index <1.5L·ml.min-1.m-2;
• Pulmonary resection;
• Pulmonary embolism ;
• Refused to participate in the study.

Trial design

425 participants in 5 patient groups

Control group

Description:

25 gender and age matching healthy controls

Treatment:

Other: no intervention

ARDS group 1

Description:

100 ARDS patients at the time of check in hospital

Treatment:

Other: no intervention

ARDS group 2

Description:

100 ARDS patients at the time of 24h after check in hospital

Treatment:

Other: no intervention

ARDS group 3

Description:

100 ARDS patients at the time of 48h after check in hospital

Treatment:

Other: no intervention

ARDS group 4

Description:

100 ARDS patients at the time of 72h after check in hospital

Treatment:

Other: no intervention