Figure 1.

Nomenclature of different types of fatty acids (FAs) and their effects in pancreatic β-cells according to chain length and degree of saturation. FAs are composed by a carboxyl moiety bonded to an aliphatic tail, with variable number of carbons. Depending on the number of carbons, FAs can be divided in short-chain (C ≤ 5), medium-chain (C6-C12), long-chain (C13-C21) and very long-chain (C ≥ 22). They can also be: (i) saturated, with no double bonds, as stearic acid (C18:0); (ii) unsaturated, with one double bond, as oleic acid (C18:1); and (iii) poly-unsaturated, with more than two double bonds, as linoleic acid (C18:2) and γ-linolenic acid (C18:3). FAs are known to increase the glucose-stimulated insulin secretion (GSIS), but can also be toxic in the long-term. The potency of GSIS amplification is positively influenced by the carbon chain length and negatively influenced by the degree of unsaturation.