Ace and Ace2 Activities and Polymorphisms Assessment: A Populational Study from Ipaussu (Sp, Brazil) During the Covid-19 Pandemic

Aim:The angiotensin-converting enzyme 2 (ACE2) and its homolog, the angiotensin-converting enzyme 1 (ACE),are involved in COVID-19 physiopathology. Alterations in the enzymatic structure, expression, and/or activity may influence the risk of infection and severity of disease. For this reason, we aimed to identify different allelic forms of ACE2 G8790A and ACEI/D polymorphisms in a Brazilian cohort and evaluate theirimpact on ACE and ACE2 activities and their association with COVID-19 susceptibility and severity.Main methods:A total of549 COVID-negative and 270 COVID-positive participants from Ipaussu, Sao Paulo, Brazil, were recruited. ACE2 and ACE activities were measured by fluorogenic assays using Mca-APK(Dnp) as the substrate for ACE2 and Z-Phe-His-Leu-OH (Z-FHL) and Hippuryl-His-Leu-OH (h-HL) as substrates for ACE. Genomic DNA was extracted from EDTA-peripheral blood, and the regions of the genes containing ACE2 G8790A and ACE I/D polymorphisms were amplified by PCR-restriction fragment length polymorphism and real-time PCR, respectively.Key findings:The G allele of ACE2 G8790A polymorphism and D allele of ACE I/D polymorphism are associated with upregulation of RAS, characterized by increased ACE and ACE2 activities. ACE activity ratio (Z-FHL/h-HL), an inflammatory marker, is increased in women with GG genotype and COVID-positive diagnosis.Significance:The G or GG and DD genotypes are associated with overactivity of RAS, increased ACE’s N-domain activity, and upregulation of soluble ACE2,which may indicate depletion of their local effects, all features related to a pro-inflammatory state, which supports the findings of these genotypes being related to more severe cases of COVID-19.