The role of membrane and circulating forms of ACE 2 in pathological processes in COVID-19 infection

The review analyzes milestone information about the function and pathogenic significance of human angiotensin-converting enzyme 2 (ACE2). ACE2 is involved in the development of diseases such as hypertension, malabsorption of certain amino acids in the intestine, and a new type of pneumonia COVID-19 caused by the SARSCoV-2 virus. Based on the latest literary sources, an assessment is made of the role of differential expression of receptor and soluble forms of this protein in the functioning of the renin-angiotensin-aldosterone system, as well as the mechanisms of ACE2 participation in the sequential chemical conversion of angiotensin II and its effect on the function of the cardiovascular system. The role of ACE2 in the development of inflammatory processes in the intestine and its effect on the composition of the intestinal microbiota are also discussed. In addition, the review presents most general data on the proteolytic activation of the S-glycoprotein of the SARS-CoV-2 virus and its participation, together with ACE2, in the process of virus introduction into the host cell. In conclusion, the hypothesis about autoimmune complications of COVID-19 associated with the formation of the S-glycoproteinACE2 immune complex and the production of autoantibodies is considered.