The Role of Circulating CircRNAs and MicroRNAs in Acute Lung Injury

Study Overview
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Brief Summary
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Efforts to identify circulating factors that predict severity of acute lung injury/acute respiratory distress syndrome（ALI/ARDS）patients is unrevealing. The primary purpose of this study is to verify circRNAs and microRNAs might be potential novel ALI/ARDS biomarkers and could play roles in pathogenesis of ALI/ARDS.

Detailed Description
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Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a devastating cause of morbidity and mortality characterized by alveolar epithelial and endothelial injury. Despite recent advances in pathogenetic mechanisms and therapy strategies of ALI, efforts to identify circulating factors that predict severity of ALI/ARDS patients have been unrevealing. Circular RNAs (circRNAs) are a novel class of endogenous non-coding RNA with a covalently continuous closed-loop structure. Compared with traditional linear RNAs, circRNAs are more stable and resistant to RNase R due to the absence of 5' caps and 3' tails, which show clear advantages in acting as novel molecular biomarkers for many diseases. In addition, many studies have reported that circRNAs can bind to microRNAs (miRNAs), acting as miRNA sponges which are named competitive endogenous RNAs (ceRNAs), and can regulate gene expression at the transcriptional or post-transcriptional level. Evidence indicates that circRNAs play important roles in cancers and other diseases such as tuberculosis and intervertebral disc degeneration. As no published research has studied the expression and role of circRNAs in the pathology and pathogenesis of ALI/ARDS, the investigators aimed to validate the aberrant expression of circRNAs in ALI/ARDS and explore the potential pathological mechanism in which circRNAs are involved.

Official Title
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Relationship Between Circulating CircRNAs and MicroRNAs and Severity of Experimental and Clinical ALI/ARDS

Conditions
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Acute Lung Injury, Acute Respiratory Distress Syndrome

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of ALI/ARDS Informed consent was obtained from either the subjects themselves or from designated surrogates before enrollment in the study. Exclusion Criteria: Patients who have chronic lung disease before enrollment. Patients who have severe organ dysfunction, autoimmune diseases and tumor. Women who are pregnant or breast-feeding. Patients who, in the opinion of the Investigator, have any other medical condition which renders the patient unable to complete the study or which would interfere with optimal participation in the study or produce significant risk to the patient. Patients participating in or planning to enroll in another clinical trial during the time of the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ARDS patients<br>137 patients were enrolled consecutively over a two-year time period (2017-2018) and identified as ARDS prospectively according to the Berlin definitions of the European Society of Intensive Care Medicine and American Thoracic Society on ARDS. Exclusion criteria were an age of less than 18 years, pregnancy, chronic obstructive pulmonary disease according to medical history and failure to obtain informed consent. | |
| Healthy volunteers<br>Forty healthy volunteers recruited from the general population who had no significant medical history and no medications were categorized as control patients. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants Receiving Mechanical Ventilation |  | up to 28 days | 
| Fraction of Inspired Oxygen (FiO2)/Partial Arterial Oxygen Pressure (PO2) |  | up to 28 days | 
| Acute Physiology and Chronic Health Evaluation (APACHE) II Scores | APACHE II scores range from 0 to 71. A higher values represent a worse outcome | up to 28 days | 
| plasma circRNAs |  | Day 3 | 
| plasma microRNAs |  | Day 3 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of Stay in the ICU |  | 1 year | 
| Length of Hospital Stay |  | 1 year | 
| Days of Unassisted Ventilation |  | 1 year | 
| Death |  | up to 28 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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circRNAs, microRNAs