Which class of lipids is involved in cell signaling?

Eicosanoids are a class of lipids that play a crucial role in cell signaling. They are derived from the fatty acid arachidonic acid and include molecules such as prostaglandins, thromboxanes, and leukotrienes. These signaling molecules are important mediators in various physiological processes, including inflammation, immune responses, and the regulation of blood pressure.

In contrast, while phospholipids and sphingolipids are also important in cellular functions, such as forming cell membranes and participating in signaling cascades, they are not primarily classified as signaling molecules. Triacylglycerides are primarily involved in energy storage and are not significant in the context of cell signaling.

Eicosanoids, due to their derivatives from membrane phospholipids and capacity to activate specific receptors on target cells, are critical in mediating a variety of biological responses, highlighting their importance in cell signaling pathways.