6. Summary
According to above compelling evidences, we speculated that consumption
of ACE2 would enhance the ACE/Ang Ⅱ/AT1R axis but inhibit the ACE2/Ang
(1-7)/MasR axis, which resulted in imbalance of RAAS, and thus increased
the inflammatory response. Rebalancing the RAAS may be the therapeutic
and preventive strategy for COVID-19 patients. Interventions for
rebalancing the RAAS include the treatment of rhACE2, ACEI/ARB, Ang
(1-7), alamandine and so on. These interventions may upregulate ACE2
expression, while there is no evidence to support the possibility of
increasing the susceptibility of SARS-CoV-2. Nevertheless, the
experimental findings have demonstrated that upregulating ACE2 may shift
the balance of RAAS axes from ACE/Ang Ⅱ/AT1R axis to the ACE2/Ang
(1-7)/Mas axis. Meanwhile, lots of clinical trials have demonstrated
rebalancing the RAAS does play a protective role in improvement of
inflammation. Therefore, we discuss our current understanding about the
role of ACE2 in organs injury secondary to the COVID-19, explore the
benefit effects of the ACE2/Ang (1-7)/Mas axis, and then make our point
that rebalances the RAAS can be the therapeutic and preventive strategy.
However, further investigation is required to demonstrate whether these
experimental effects could be translated into clinical benefit.