Enteric nervous system as a target and source of SARS-CoV-2 and other viral infections

Coronavirus disease 2019 (COVID-19) has been demonstrated to affect several systems of the human body, including the gastrointestinal and nervous systems. The enteric nervous system (ENS) is a division of the autonomic nervous system that extends throughout the gut, regulates gastrointestinal function, and is therefore involved in most gut dysfunctions, including those resulting from many viral infections. Growing evidence highlights enteric neural cells and microbiota as important players in gut inflammation and dysfunction. Furthermore, the ENS and gastrointestinal immune system work together establishing relevant neuroimmune interactions during both health and disease. In recent years, gut-driven processes have also been implicated as players in systemic inflammation and in the initiation and propagation of several central nervous system pathologies, which seem to be hallmarks of COVID-19. In this review, we aim to describe evidence of the gastrointestinal and ENS infection with a focus on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We discuss here viral-induced mechanisms, neuroplasticity, and neuroinflammation to call attention to the enteric neuroglial network as a nervous system with a sensitive and crucial position to be not only a target of the new coronavirus but also a way in and trigger of COVID19-related symptoms.

Automated summary

Coronavirus disease 2019 (COVID-19) affects the gastrointestinal and nervous systems, with the enteric nervous system (ENS) and gut microbiota playing important roles in gut inflammation and dysfunction. The ENS and gastrointestinal immune system work together during health and disease. Gut-driven processes are also implicated in systemic inflammation and central nervous system pathologies associated with COVID-19. This review focuses on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the gastrointestinal and ENS, highlighting viral-induced mechanisms and the role of the enteric neuroglial network in COVID-19-related symptoms.