RESUMO
BACKGROUND: Metabolic dysregulation and excessive inflammation are implicated in the pathogenesis of the highly infectious disease of coronavirus disease 2019 (COVID-19), which is caused by a newly emerging coronavirus (i.e., severe acute respiratory syndrome-coronavirus 2; SARS-CoV-2). The adenosine 5'-monophosphate-activated protein kinase (AMPK), an energy sensor regulating the metabolic pathways in diverse cells, exerts a regulatory role in the immune system. This study aims to examine the mRNA expression level of AMPK and the plasma levels of interleukin-6 (IL-6) and IL-10 cytokines in patients with different grades of COVID-19. METHODS: Peripheral blood was collected from 60 patients with COVID-19 (Moderate, severe, and critical). The plasma levels of IL-6 and IL-10 were quantified by enzyme-linked immunosorbent assay (ELISA), and the mRNA expression level of AMPK was determined using real-time PCR. RESULTS: The results showed that the plasma levels of IL-6 increased significantly in critical and severe patients compared to moderate cases of COVID-19 (P < 0.001). Moreover, IL-10 plasma concentrations were significantly higher in critical and severe cases than in moderate cases of COVID-19 (P < 0.01 and P < 0.05, respectively). Also, the gene expression of AMPK was meaningfully enhanced in critical patients relative to moderate and severe cases of COVID-19, in order (P < 0.001 and P < 0.01, respectively). There was a positive association between AMPK gene expression and plasma levels of IL-6 and IL-10 (P = 0.006, r = 0.348, P = 0.028, r = 0.283, respectively). CONCLUSION: Increasing AMPK gene expression is likely a necessary effort of the immune system to inhibit inflammation in critical COVID-19. However, this effort seems to be inadequate, probably due to factors that induce inflammation, like erythrocyte sedimentation rate (ESR) and IL-6.