Avaluació de miRNAs en plasma com a biomarcadors de resposta en pacients PACS amb deteriorament cognitiu

Abstract

The post-acute COVID 19 syndrome, also described as PACS, affects 10-15% of people who have

been infected by SARS-CoV-2. The current definition of PACS is the persistence or development of

symptoms from the fourth week after infection. Symptoms can be very diverse including fatigue,

dyspnea, anosmia, thoracic pain, cognitive impairment, mental fog, arthralgia and mental health

problems. Specifically, PACS patients with cognitive impairment represent a high percentage of

PACS, it affects the entire population and currently there is no treatment. REHABCOVID is a

coordinated project to evaluate the effectiveness of a digital solution for the rehabilitation of patients

with PACS with cognitive impairment by conducting a study through a simple blind randomized clinical

trial. The Cellular and Molecular Neurobiology research group of the UdG has directed the subproject

for the analysis of a set of candidate miRNAs in plasma as biomarkers of diagnosis of this syndrome

and possible biomarkers of the effect of treatment.

In this work, miR-450a-5p, miR-483-3p and miR-448 have been evaluated as biomarkers of response

to rehabilitation treatment in three groups that presented PACS with cognitive impairment: a control

group (RCO), a group with online rehabilitation (RCO) and a group with face-to-face rehabilitation

(RCP). To see the changes in expression of miRNAs, a plasma RNA extraction from patients, a

retrotranscription and a real-time quantitative PCR have been carried out, in which the levels of

expression before and after treatment have been compared. The results of the expression levels of

the study miRNAs have been correlated with results of neuropsychological tests.

While for miR-448 and miR-483-3p the results could not be analyzed due to a problem in the

methodology; in the case of miR-450a-5p, a differential increase in the relative abundance between

before and after treatments has not been found; for the moment, it is not possible to say that it is a

good candidate for biomarker of response to treatment. On the other hand, a correlation between

miR450a-3p and four test types has been found: two types of Stroop and RAVLT tests for immediate

and delayed memory, indicating that miR450a-3p can be related to processing speed and memory.

It would be advisable to do more studies with a longer treatment to understand its relationship with

cognition mechanisms

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