Effect of diet-induced plasma ceramide on human in vivo microvascular endothelial function.

In 30 seconds

This double-blind, randomized crossover trial examined whether a meal-induced rise in plasma ceramides impairs in vivo microvascular function in 23 healthy young adults. Participants consumed meals rich in long-chain or medium-chain fatty acids, with measurements at baseline and 2 and 4 hours. The long-chain meal increased circulating ceramides in female participants only (P < 0.001), but nitric oxide-dependent and maximal dilation declined similarly after both meals, without sex differences. Microvascular density and perfusion did not change. The findings suggest that an acute ceramide increase was not sufficient to explain the post-meal reduction in microvascular function.

Key findings

• The long-chain fatty acid-rich meal increased circulating ceramides in female participants only (P < 0.001).
• Nitric oxide-dependent and maximal dilation were similarly reduced after both meals, with no observed sex differences.
• Neither meal changed microvascular density or perfusion.

Why it matters

The results distinguish an acute postprandial reduction in microvascular function from a simple effect of circulating ceramide: function declined after both meals, although ceramide elevations occurred only after the long-chain meal. This cautions against attributing short-term vascular responses to ceramide changes alone and highlights the need to understand whether repeated ceramide elevations have different effects.

What to keep in mind

The trial assessed acute responses in a small group of healthy young adults; it does not establish the effects of repeated ceramide elevations or longer-term cardiovascular outcomes.