Cross-linking versus RAGE: How do high molecular weight advanced glycation products induce cardiac dysfunction?

Area of Science:

• Cardiology
• Biochemistry
• Pathophysiology

Background:

• Advanced glycation end products (AGEs) are linked to adverse cardiac outcomes.
• High molecular weight AGEs (HMW-AGEs) may play a significant role, but their involvement in cardiac remodeling is unclear.

Purpose of the Study:

• To investigate the role of HMW-AGEs in the pathogenesis of cardiac dysfunction.
• To determine if HMW-AGEs contribute to cardiac remodeling and fibrosis.

Main Methods:

• Rats were injected with BSA-derived HMW-AGEs or unmodified BSA for 6 weeks.
• Cardiac function was assessed via echocardiography.
• Plasma markers and cardiac tissue expression of AGEs, RAGE, and LOX were analyzed.

Main Results:

• HMW-AGEs induced cardiac dysfunction, hypertrophy, and fibrosis with increased lysyl oxidase (LOX) expression.
• Elevated plasma soluble RAGE (sRAGE) correlated with decreased cardiac strain.
• No significant changes in RAGE, TNF-α, or IL-6 expression were observed.

Conclusions:

• HMW-AGEs cause cardiac stiffness and dysfunction primarily through collagen cross-linking, independent of RAGE activation.
• Increased sRAGE levels serve as a marker for cardiac dysfunction in the presence of elevated HMW-AGEs.