Interactions between oxidative stress and inflammation in salt-sensitive hypertension

Area of Science:

• Nephrology
• Cardiovascular Research
• Oxidative Stress Biology

Background:

• High-salt intake is a known contributor to hypertension and kidney damage.
• Oxidative stress and inflammation are implicated in the pathogenesis of salt-sensitive hypertension.
• Nuclear factor-kappaB (NF-kappaB) signaling plays a role in renal inflammation.

Purpose of the Study:

• To investigate the role of oxidative stress in high-salt-induced renal inflammation and hypertension in Dahl S rats.
• To determine if antioxidant treatment (Vitamins C and E) can mitigate these effects.

Main Methods:

• Dahl S rats were fed a high-salt diet with or without antioxidant supplementation (Vitamins C and E) for 5 weeks.
• Renal oxidative stress markers, NF-kappaB activation, inflammatory cell infiltration, and renal function were assessed.
• Hemodynamic parameters and renal damage were evaluated.

Main Results:

• Antioxidant treatment significantly reduced markers of oxidative stress (glutathione ratio, H2O2, O2*- release) in the kidneys.
• Treatment decreased renal NF-kappaB activation, inflammatory cell infiltration (monocytes/macrophages), and key inflammatory mediators (TNF-α, MCP-1).
• High-salt-induced hypertension, proteinuria, and renal damage were attenuated by antioxidants, while GFR and RPF improved.

Conclusions:

• Increased oxidative stress in high-salt-fed Dahl S rats stimulates renal NF-kappaB, leading to inflammation, hypertension, and kidney damage.
• Antioxidant therapy effectively reduces renal inflammation and attenuates adverse cardiovascular and renal outcomes.
• Vitamins C and E represent a potential therapeutic approach to manage salt-sensitive hypertension and protect kidney function.