Plasma and white adipose tissue lipid composition in marmots

Area of Science:

• Comparative physiology
• Lipid metabolism
• Animal models

Background:

• Hibernating mammals undergo significant physiological changes.
• Understanding lipid metabolism during hibernation is crucial for survival.
• Yellow-bellied marmots (Marmota flaviventris) serve as a model for hibernation research.

Purpose of the Study:

• To investigate the fatty acid composition and metabolism in white adipose tissue and plasma of hibernating yellow-bellied marmots.
• To determine preferential fatty acid utilization during the hibernation period.
• To evaluate marmots as a model for studying lipid metabolism.

Main Methods:

• Biopsies of white adipose tissue and plasma samples were collected from hibernating and normothermic marmots.
• Analysis of fatty acid composition in white adipose tissue triacylglycerol and plasma.
• Measurement of plasma free fatty acid levels to assess lipolysis.

Main Results:

• White adipose tissue fatty acid composition was simple and uniform, dominated by palmitic, oleic, and linoleic acids.
• Hibernating marmots showed increased lipolysis and changes in adipose tissue fatty acid percentages throughout the season.
• Plasma fatty acid analysis suggested preferential metabolism of saturated fats during hibernation and mobilization of dienes post-hibernation.

Conclusions:

• Marmots preferentially metabolize saturated fats during hibernation.
• Essential fatty acids, particularly omega-6 series, appear to be metabolized more slowly.
• Marmots represent a valuable animal model for investigating lipid metabolism, especially concerning fatty acid utilization during prolonged fasting and cold exposure.