[The renin-angiotensin-aldosterone system -- more complex as previously thought]

Area of Science:

• Nephrology
• Cardiovascular Pharmacology
• Renal Pathophysiology

Background:

• Angiotensin II (ANG II) significantly contributes to chronic kidney disease progression through pro-inflammatory and profibrotic effects.
• Local ANG II generation in kidneys, particularly in proximal tubular cells, occurs independently of systemic levels and is not fully inhibited by current therapies.

Purpose of the Study:

• To explore the complexity of the renin-angiotensin-aldosterone system (RAAS) and its implications for renal disease treatment.
• To evaluate the rationale and clinical evidence for dual RAAS blockade strategies.

Main Methods:

• Review of existing literature on local ANG II generation and RAAS component interactions.
• Analysis of clinical studies investigating dual blockade therapies (ACE inhibitors and AT(1) receptor antagonists) versus monotherapies.

Main Results:

• Local renal ANG II systems exhibit complex pathways, including alternative peptide generation (e.g., angiotensin 1-7) and degradation products (e.g., angiotensin IV).
• Emerging understanding of AT(1) receptor dimers and agonistic antibodies adds to system complexity.
• Clinical studies indicate dual RAAS blockade is more effective than monotherapy in slowing chronic kidney disease progression in certain populations.

Conclusions:

• The intricate nature of the RAAS supports dual blockade strategies for managing chronic renal diseases.
• Novel pathophysiological insights into the RAAS are driving innovative clinical treatment approaches for kidney disease.