The relationship between circulating irisin levels and endothelial function in lean and obese subjects

Area of Science:

• Endocrinology
• Metabolic Syndrome
• Vascular Biology

Background:

• Irisin, a myokine, influences adipocyte browning and is a potential therapeutic target for obesity.
• Endothelial dysfunction is a key factor in the development of cardiovascular complications associated with obesity.

Purpose of the Study:

• To investigate the association between circulating irisin levels and endothelial dysfunction in obese subjects.
• To compare irisin levels and endothelial function in obese individuals versus lean healthy controls.

Main Methods:

• A study involving 41 obese and 40 lean healthy subjects.
• Measurement of clinical characteristics, blood biochemistry, circulating irisin, and adiponectin.
• Assessment of endothelium-dependent vasodilation (EDV) and endothelial-independent vasodilation (EIV) using high-resolution ultrasound.

Main Results:

• Obese subjects exhibited significantly lower circulating irisin and adiponectin levels compared to lean controls.
• Endothelial function, measured by maximum EDV, was impaired in obese subjects.
• Circulating irisin positively correlated with EDV and negatively with BMI, waist circumference, FFA, hs-CRP, and malondialdehyde.
• Irisin, adiponectin, FFA, and BMI were independently associated with EDV in multiple regression analysis.

Conclusions:

• Circulating irisin levels are reduced in obese individuals without hypertension or diabetes.
• Lower irisin levels are independently associated with endothelial dysfunction in obesity.
• Irisin may be implicated in the regulation of endothelial function within the context of obesity.