High levels of extracellular ATP lead to different inflammatory responses in COVID-19 patients according to the severity.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has significantly impacted the world and has driven many researchers into the pathophysiology of COVID-19. In the findings, there is a close association between purinergic signaling and the immune response. Then, this study aimed to evaluate alterations in the purinergic signaling in COVID-19 patients according to range severity. We divided the COVID-19 patients into moderate and severe cases following the guideless of NIH and WHO, together with clinical characteristics. The blood samples were collected to obtain PBMCs and platelets. We analyzed the ectonucleotidase activities through ATP, ADP, AMP, Ado hydrolysis, E-NTPDase1 (CD39), and 5'-NT (CD73) expression by flow cytometry in total leukocytes. The extracellular ATP was measured by bioluminescence, and cytokines were analyzed by flow cytometry. We observed a decrease in ATP hydrolysis and increased AMP hydrolysis in PBMCs for both groups. In severe cases, ATP hydrolysis was raised for the platelets, while ADP and AMP hydrolysis have risen significantly in both groups. Additionally, there was a significant increase in ADP hydrolysis in severe cases compared to moderate cases. In addition, we observed an increase in the ADA activity in platelets of moderate patients. Moderate and severe cases showed increased expression of CD39 and CD73 in total leukocytes. To finalize the purinergic signaling, extracellular ATP was increased in both groups. Furthermore, there was an increase in IL-2, IL-6, IL-10, and IL-17 in moderate and severe groups. Thus, for the first time, our findings confirm the changes in purinergic signaling and immune response in COVID-19, in addition to making it more evident that the severity range directly impacts these changes. Therefore, the therapeutic potential of the purinergic system must be highlighted and studied as a possible target for the treatment of SARS-CoV-2 disease. KEY MESSAGES: COVID-19 patients exhibit alterations in purinergic system and immune response. High levels of extracellular ATP lead to different inflammatory responses. CD39 and CD73 expression were increased in COVID-19 patients. Cytokines IL-2, IL-6, IL-10, and IL-17 also were altered in these patients. The purinergic system may be a possibility target to SARS-CoV-2 treatments.

Impact of COVID-19 in the Mental Health in Elderly: Psychological and Biological Updates.

Since December 2019, the world has been experiencing the challenge of facing coronavirus disease-19 (COVID-19), a severe infectious disease caused by the new coronavirus, SARS-CoV-2. The individuals with the most severe symptoms and the highest risk of death are the elderly and those with chronic illness. Among chronic conditions, those with a certain degree of chronic inflammation may predispose to a more severe evolution of COVID-19. Elderly with psychiatric disorders can present a persistent inflammatory state, a characteristic of the age's immunological senescence, but the disorder can accentuate that. Social isolation is still the safest way to avoid contamination. However, isolated older people may have or worsen mental health conditions due to isolation and health concerns. In this scenario, a SARS-CoV-2 infection may progress to more severe disease. Conversely, COVID-19 can predispose or aggravate psychiatric disorders, as it induces a cytokine storm, causing systemic hyper inflammation. It may damage the blood-brain barrier, resulting in inflammation in the central nervous system. Besides, SARS-CoV-2 is likely to reach and trigger an inflammatory process directly in the nervous system. This review makes an update about research on the mental health of the elderly during the pandemic. Also, it discusses the vulnerability of these individuals in the face of stress and in the case of contracting COVID-19, considering mainly the stress's hormonal and inflammatory mechanisms. Finally, the review points out possible care and attention strategies and entertainment and activities that can reduce the damage to mental and physical health and improve the elderly's quality of life. Graphical abstract Isolation and concerns about COVID-19 may harm elderly mental health. Immunosenescence and pandemic stress increase the risk of psychiatric disorders. Stress and disorders may potentiate the elderly's inflammation and COVID-19 symptoms. SARS-CoV-2 hyperinflammation is a risk factor for elderly psychiatric disorders.