Question

ACE2 is cleaved by proteases and released as a soluble or plasma protein. Plasma ACE2 is associated with cardiovascular disease risk factors and is elevated in type 1 diabetics, hypertensive patients, and patients with kidney disease. Hypothesize why “tissue” (cell membrane bound) ACE2 is cardioprotective, but plasma ACE2 is associated with disease.

Answer 1

Renin angiotesnin system (RAS) is involved in the homeostatic regulation of the cardiovascular and kidney system.Inhibition of the RAS system causes the progression of the decrease. The RAS metabolic pathway involves the steps which includes the angiotensinogen gets converted into angiotensin I by action of the renin ,further angiotensin I gets cleaved and converted into angiotensin II by the action of  ACE .Angiotensin II gets cleaved by the ACE2 and converted into Angiotensin 1-7 .The angiotensin II acts upon the receptors named as Ang type I (AT1)and type 2 (AT2) receptors and angiotensin II acts on the Mas receptos and helps in balancing angiotensinII / Ang type I receptor actions.

The tissue cell membrane bound ACE2 causes the shifts the balance to the RAS system axis named as angiotensin 1-7/Mas receptor  axis and results into antihypotrophic,anti-oxidant, vasodilation effect and protect from the cardiac disease (cardioprotection)

Plasma ACE2 causes the shift of the RAS system to angiotensinII/ AT1 R axis ,results into vasoconstriction ,hypertrophy and cell proliferation.Thus results into disease progression.