Palmitic but Not Oleic Acid Induces Pro-Inflammatory Dysfunction of Human Endothelial Cells from Different Vascular...

Area of Science:

• Cardiovascular Biology
• Cellular Biology
• Nutritional Science

Background:

• Palmitic acid (PA) and oleic acid (OA) are common dietary fatty acids with distinct properties.
• Endothelial cells (ECs) form the inner lining of blood vessels and play a crucial role in vascular health.
• The differential responses of ECs from various vascular beds to PA and OA are not well understood.

Purpose of the Study:

• To investigate the distinct cytotoxic and pro-inflammatory effects of PA and OA on human ECs from different vascular origins.
• To compare the susceptibility of aortic valve, saphenous vein, internal thoracic artery, and microvascular ECs to these fatty acids.

Main Methods:

• Primary human aortic valve (HAVEC), saphenous vein (HSaVEC), internal thoracic artery (HITAEC), and microvascular (HMVEC) ECs were treated with albumin-bound PA or OA for 24 hours.
• Cytotoxicity was assessed, and gene expression of cell adhesion molecules and pro-inflammatory cytokines was analyzed.
• Release of key inflammatory mediators like interleukin-6 and -8 was measured.

Main Results:

• PA induced significant cytotoxicity and elevated expression of adhesion molecules (VCAM1, ICAM1, SELE, SELP) and pro-inflammatory cytokines in ECs.
• HAVEC and HSaVEC were most susceptible to PA, showing increased interleukin-6 and -8 release.
• OA exhibited mild-to-moderate cytotoxicity in HAVEC and HMVEC without widespread EC activation, while HITAEC demonstrated resistance to both fatty acids.

Conclusions:

• Significant heterogeneity exists in the response of ECs from different vascular beds to palmitic acid.
• Palmitic acid poses a greater risk for endothelial dysfunction compared to oleic acid, particularly in certain vascular ECs.
• Understanding these differential responses is crucial for assessing the vascular impact of dietary fatty acids.