ACE and metabolic syndrome: In the pathogenesis of MetS, renin-angiotensin system (RAS) is activated in various organs and tissues [3–6], and RAS inhibitors, such as angiotensin converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), are preferred for the treatments of hypertension with MetS because of the prominent depressor effect with the improvement of insulin resistance [7–9].