Cellular toxicity of dietary trans fatty acids and its correlation with ceramide and diglyceride accumulation.

High fatty acid (FA) levels are deleterious to pancreatic β-cells, largely due to the accumulation of biosynthetic lipid intermediates, such as ceramides and diglycerides, which induce ER stress and apoptosis. Toxicity of palmitate (16:0) and oleate (18:1 cis-Δ) has been widely investigated, while very little data is available on the cell damages caused by elaidate (18:1 trans-Δ) and vaccenate (18:1 trans-Δ), although the potential health effects of these dietary trans fatty acids (TFAs) received great publicity. We compared the effects of these four FAs on cell viability, apoptosis, ER stress, JNK phosphorylation and autophagy as well as on ceramide and diglyceride contents in RINm5F insulinoma cells.