Protein profiling of the myocardium exposed to pressure overload from birth

Area of Science:

• Cardiovascular Physiology
• Cardiac Remodeling
• Animal Models

Background:

• Aortic banding is a common method to induce pressure overload in the heart.
• Understanding the impact of age at banding is crucial for interpreting cardiac response.

Purpose of the Study:

• To investigate the long-term effects of early-life aortic banding on cardiac structure and protein composition.
• To compare the cardiac remodeling response between rats banded at different ages (2-day vs. 6-day-old).

Main Methods:

• Male rats underwent surgical aortic banding at 2 days (A2) or 6 days (A6) of age.
• Cardiac weight, ventricular enlargement, and protein concentrations (collagenous, sarcoplasmic, collagen types, myosin light chains) were assessed after 60 days.

Main Results:

• Both A2 and A6 groups showed increased left ventricular (LV) weight and elevated collagenous proteins at the expense of sarcoplasmic proteins.
• The A2 group exhibited right ventricular (RV) enlargement and more significant LV protein alterations, including decreased collagen I and increased collagen III/V and LC1/LC2.
• Similar, though less pronounced, protein changes were observed in the RV of both groups.

Conclusions:

• Early-life aortic banding induces significant cardiac remodeling, characterized by ventricular hypertrophy and altered protein profiles.
• The age at which banding is performed influences the extent and pattern of cardiac remodeling, with earlier banding leading to more severe effects.