Gastric bypass simultaneously improves adipose tissue function and insulin-dependent type 2 diabetes mellitus

Area of Science:

• Metabolic Surgery
• Endocrinology
• Immunology

Background:

• Adipose tissue dysfunction, characterized by high leptin, inflammation, and oxidative stress, is implicated in type 2 diabetes (T2DM).
• The

Purpose of the Study:

• Investigate changes in adipose tissue function after Roux-Y gastric bypass (RYGB) in non-severely obese patients (BMI <35 kg/m²) with insulin-dependent T2DM.
• Explore the role of adipose tissue dysfunction in T2DM development and resolution post-RYGB.

Main Methods:

• Studied 20 patients with T2DM (BMI <35 kg/m²) undergoing RYGB, assessing insulin resistance, leptin, oxidative stress, and cytokines over 24 months.
• Analyzed gene expression in peripheral blood mononuclear cells (PBMCs) and examined adipose tissue inflammation histologically pre- and post-surgery.

Main Results:

• RYGB led to significant reductions in insulin resistance, leptin levels, oxidative stress, and adipose tissue inflammation.
• Systemic inflammation decreased, with PBMCs shifting towards an M2-type inflammatory profile.
• Weight loss correlated with improvements in leptin, insulin resistance, and oxidative stress.

Conclusions:

• RYGB surgery enhances adipose tissue function and reduces inflammation in T2DM patients.
• Leptin may act as a mediator, linking adipose tissue dysfunction to improvements in insulin resistance and oxidative stress, thereby resolving T2DM.