Eosinophils protect from metabolic alterations triggered by obesity

Area of Science:

• Metabolic research
• Immunology
• Obesity research

Background:

• Eosinophils are typically linked to parasitic infections and allergies.
• Their role in metabolic alterations and adipose tissue remodeling is primarily studied in animal models of obesity.
• The precise physiological function of eosinophils in metabolic regulation remains underexplored.

Purpose of the Study:

• To investigate the involvement of eosinophils in metabolic and adipose tissue homeostasis.
• To explore the translational relevance of eosinophil function in mice and humans.
• To understand how eosinophils modulate glucose metabolism, inflammation, and fat accumulation.

Main Methods:

• Utilized wild-type (WT) and GATA-1 knockout (Δdb/GATA-1-/-) mice.
• Administered regular, high-carbohydrate (HC), or high-fat (HF) diets to mice.
• Analyzed clinical parameters and omental adipose tissue (AT) gene expression in obese human subjects.

Main Results:

• Eosinophil deficiency in mice on a regular diet led to insulin resistance and increased adiposity.
• Adipose tissue in eosinophil-deficient mice exhibited elevated cytokine levels and increased leukocyte infiltration.
• Bone marrow transplants partially restored glucose metabolism and reduced fat mass in recipient mice.
• Dietary challenges exacerbated adiposity and glucose dysfunction in eosinophil-deficient mice, particularly with HF diets.
• In humans with severe obesity, eosinophil marker expression correlated with inflammatory markers and insulin sensitivity indicators.

Conclusions:

• Eosinophils appear to regulate systemic and adipose tissue metabolic homeostasis.
• They modulate glucose metabolism, inflammation, and visceral fat expansion, even in lean individuals.
• Eosinophils also influence glucose homeostasis in human obesity.