Inguinal Fat Compensates Whole Body Metabolic Functionality in Partially Lipodystrophic Mice with Reduced PPARγ...

Area of Science:

• Metabolic diseases
• Genetics
• Endocrinology

Background:

• Mutations in the peroxisome proliferator-activated receptor gamma (PPARγ) gene cause insulin resistance and partial lipodystrophy.
• The role of preserved fat depots in partial lipodystrophy's metabolic homeostasis remains unclear.

Purpose of the Study:

• To investigate the insulin response and metabolic gene expression in preserved fat depots of a familial partial lipodystrophy type 3 (FPLD3) mouse model.
• To determine the compensatory role of inguinal fat in whole-body metabolic homeostasis.

Main Methods:

• Analysis of insulin response and metabolic gene expression in inguinal and perigonadal fat depots of Pparg mice.
• Assessment of whole-body insulin sensitivity following inguinal fat removal.
• Evaluation of PPARγ agonist effects on insulin sensitivity and metabolic ability.

Main Results:

• Pparg mice exhibited reduced insulin sensitivity and adipose tissue mass in perigonadal fat but compensatory increases in inguinal fat.
• Inguinal fat maintained normal metabolic gene expression in basal and fasting/refeeding states, with enhanced insulin sensitivity under high nutrient load.
• Inguinal fat removal worsened whole-body insulin sensitivity, while PPARγ activation restored perigonadal fat function.

Conclusions:

• Compensatory mechanisms in inguinal fat help mitigate metabolic abnormalities in FPLD3.
• Preserved inguinal fat depots play a crucial role in maintaining whole-body metabolic homeostasis in the context of partial lipodystrophy.
• Targeting PPARγ may offer therapeutic potential for metabolic dysregulation in lipodystrophy.