The angiotensin converting enzyme 2 (ACE2) system in the brain: possible involvement in Neuro-Covid

The brain has its own intrinsic reninangiotensin system (RAS) with all its components present in the central nervous system (CNS). Recent data demonstrate that also the main components of the angiotensin concerting enzyme 2 (ACE2) system (at least ACE2 itself, as well as the biologically active angiotensin (1-7) and its cognate receptor Mas) are expressed in the brain. Aside from these members, alamadine and MrgD are discussed as further members that have neuro-active roles in the CNS. Little is known about the possible functions of MrgD within the brain. Concerning angiotensin (1-7) acting through the Mas receptor, data were accumulating that this system is involved in numerous processes contributing to neuronal plasticity and even learning and memory. Malfunctions in the brain ACE2 system are associated with disturbances in neuronal plasticity. Since SARS-CoV-2 has a high affinity towards ACE2, Neuro-Covid may directly or indirectly depend on a disturbed balance in the ACE2 derived angiotensin system in the brain. Since the ACE2 system in the brain is far from being understood, a deeper understanding of e.g. the angiotensin (1-7) / Mas system is needed, especially with regard to the roles of angiotensin (1-7) in neuronal

Automated summary

The brain has its own intrinsic renin-angiotensin system (RAS) and ACE2 system, which play important roles in processes such as neuronal plasticity and learning and memory. Malfunctions in the brain ACE2 system are associated with disturbances in neuronal plasticity, and it is possible that Neuro-Covid may depend on a disturbed balance in the ACE2 system due to the high affinity of SARS-CoV-2 towards ACE2.