Two-Hour Postprandial Lipoprotein Particle Concentration Differs Between Lean and Obese Individuals

Area of Science:

• Metabolic health and cardiovascular disease risk
• Lipoprotein metabolism and postprandial responses

Background:

• Lipoprotein particle concentrations are linked to cardiovascular disease risk.
• Most research focuses on fasting states, overlooking postprandial changes.
• Obesity and insulin resistance may alter postprandial lipoprotein metabolism.

Purpose of the Study:

• To investigate short-term postprandial lipoproteinemia in obese insulin-resistant (obese-IR) versus lean insulin-sensitive (lean-IS) men.
• To compare the effects of different meal compositions (high-protein, high-fat, high-carbohydrate) on lipoprotein concentrations.

Main Methods:

• Randomized crossover trial involving nine obese-IR and nine lean-IS Chinese men (aged 22-35).
• Administration of isoenergetic, isovolumic meals rich in protein, fat, or carbohydrate.
• Plasma lipoprotein analysis using nuclear magnetic resonance at fasting, 1-h, and 2-h post-meal.

Main Results:

• Obese-IR subjects had higher concentrations of large very-low-density lipoproteins (VLDLs) and chylomicrons, with greater post-meal increases compared to lean-IS subjects.
• High-protein meals reduced small low-density lipoprotein (LDL) particle concentration in obese-IR subjects.
• High-fat meals decreased small high-density lipoprotein (HDL) particle concentration in all subjects.

Conclusions:

• Obese-IR subjects exhibit a detrimental postprandial lipoprotein response to various meals.
• Adverse lipoprotein changes occur as early as 2 hours after meal intake in obese-IR individuals.
• These findings suggest an increased short-term cardiovascular risk in obese-IR individuals post-meal.