Cardiac hypertrophy-related pathways in obesity

Area of Science:

• Cardiology
• Metabolic Disorders
• Molecular Biology

Background:

• Obesity is linked to cardiac hypertrophy, but the underlying molecular pathways are not fully understood.
• Identifying these pathways is crucial for understanding and treating obesity-related heart disease.

Purpose of the Study:

• To investigate cardiac hypertrophy markers and pathways in obese rats.
• Specifically evaluate atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), tumor necrosis factor-alpha (TNFα), and signaling pathways including IL-6-STAT3, IL-6-MEK5-ERK5, and calcineurin-NFAT3.

Main Methods:

• Used obese and lean Zucker rats for comparison.
• Assessed cardiac characteristics via heart weight index, echocardiography, and histology.
• Quantified protein and gene expression of hypertrophy markers and pathways using RT-PCR and Western blotting.

Main Results:

• Obese rats exhibited increased heart weight, left ventricle weight, wall thickness, and systolic blood pressure compared to lean controls.
• Elevated levels of ANP, BNP, TNFα, IL-6, STAT3, p-STAT3, MEK5, ERK-5, p-ERK-5, calcineurin, and NFAT3 were observed in obese rat hearts.
• Hypertrophy-related markers and pathways were significantly more active in obese rats.

Conclusions:

• Obesity activates specific cardiac hypertrophy markers (ANP, BNP, TNFα) and signaling pathways (IL-6-STAT3, IL-6-MEK5-ERK5, calcineurin-NFAT3).
• These activated pathways offer potential molecular mechanisms for cardiac hypertrophy and pathological changes associated with obesity.
• This study provides insights into the molecular basis of obesity-induced heart disease.