The renin-angiotensin system biomolecular cascade: a 2022 update of newer insights and concepts

Carlos M Ferrario1, Leanne Groban2, Hao Wang2

  • 1Department of Surgery, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.

Insights

Current renin-angiotensin system blockade offers limited cardiovascular risk reduction. Exploring alternate angiotensin pathways may enhance treatments for hypertension and cardiovascular disease.

Area of Science:

  • Cardiovascular Medicine
  • Biochemistry
  • Pharmacology

Background:

  • The renin-angiotensin system (RAS) is implicated in cardiovascular disease (CVD) pathogenesis.
  • Current therapies targeting RAS, like ACE inhibitors and ARBs, only partially reduce residual cardiovascular risk.
  • Limitations exist in current therapeutic approaches for hypertension and CVD based on RAS blockade.

Purpose of the Study:

  • To address limitations of current RAS blockade therapies.
  • To illustrate complex physiology and mechanisms of classical and alternate angiotensin peptide formation.
  • To provide insights for enhancing therapeutics for RAS inhibition.

Main Methods:

  • Reappraisal of the renin-angiotensin-aldosterone cascade.
  • Illustration of classical and alternate angiotensin peptide formation mechanisms.
  • Review of emerging evidence on alternate RAS pathways.

Main Results:

  • Alternate mechanisms for angiotensin production bypass renin and angiotensin-converting enzyme.
  • These tissue-specific pathways are not universally recognized.
  • Newly elucidated intermediary components and interplay within the RAS cascade are highlighted.

Conclusions:

  • Current RAS blockade therapies have limitations in fully addressing cardiovascular risk.
  • Deeper understanding of the RAS cascade, including alternate pathways, is crucial.
  • Enhanced therapeutics for RAS inhibition are needed to improve patient care in CVD.

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