Adipocyte-specific gp130 signalling mediates exercise-induced weight reduction.

Area of Science:

• Obesity research
• Metabolic signaling
• Exercise physiology

Background:

• Repetitive physical activity aids weight management by increasing energy expenditure and reducing caloric intake.
• Obesity-induced interleukin-6 (IL-6) signaling in adipose tissue influences appetite-regulating hormones like leptin and insulin.
• The role of adipocyte-specific IL-6 signaling in exercise-induced appetite control and weight reduction remains to be fully elucidated.

Purpose of the Study:

• To investigate the function of adipocyte-specific IL-6 signaling in exercise-mediated appetite control.
• To determine the impact of adipocyte-specific IL-6 signaling on weight reduction during exercise in obesity.
• To explore the molecular mechanisms linking IL-6 signaling, appetite hormones, and exercise in diet-induced obesity.

Main Methods:

• Utilized adipocyte-specific glycoprotein 130 knockout (gp130Δadipo) and control (gp130F/F) mice subjected to a 12-week high-fat diet (HFD) and exercise regimen.
• Assessed thermogenesis, food intake, and energy expenditure using thermography and metabolic cages.
• Measured circulating IL-6, insulin, and leptin levels, and analyzed hypothalamic signaling pathways (pSTAT3, pJAK2, pAkt) via Western blot.

Main Results:

• Exercise reduced food intake and weight gain in control mice but not in gp130Δadipo mice.
• Energy expenditure did not differ between genotypes, but circulating insulin and leptin levels were reduced in gp130Δadipo mice.
• Hypothalamic leptin and insulin signaling were enhanced in exercised control mice, but not in gp130Δadipo mice.

Conclusions:

• Adipocyte-specific IL-6 signaling is crucial for exercise-mediated regulation of food intake.
• This signaling pathway plays a significant role in exercise-induced weight reduction in diet-induced obesity.
• Targeting adipocyte IL-6 signaling may offer therapeutic strategies for managing obesity through exercise.