Gut-related metabolites are associated with respiratory symptoms in COVID-19: a proof-of-concept study

Gut-related metabolites have been linked with respiratory disease. The crosstalk between the gut and lung suggests that gut health may be compromised in COVID-19. The aims of the present study were to analyse a panel of gut-related metabolites (acetyl-L-carnitine, betaine, choline, L-carnitine, trimethylamine and TMAO) in COVID-19 patients, matched with healthy subjects, and non-COVID-19 respiratory patients. As results, metabolites from this panel are impaired in COVID-19, associated with symptoms (breathlessness and temperature) and able to differentiate between COVID-19 and asthma. Preliminary results show lower levels of betaine appear to be associated with poor outcomes in COVID-19 patients suggesting betaine as a marker of gut microbiome health.