Trans Fatty Acids (TFA) are unsaturated fatty acids with at least one double bond in the trans configuration, that renders them structurally/chemically similar, but also unstable, compared to Saturated Fatty Acids (SFA). TFA predominately incorporate into the phospholipid components, specifically into the plasma membranes, at the expense of SFA palmitic, stearic and to lesser extent myristic acid.
Trans fats are not an homogeneous group of molecules; in fact, specific isomeric configuration in different TFA may exhibit different biological effects, and very little is known about the cellular effects of individual members of the group, even if there is substantial literature indicating pro-inflammatory and pro-oxidative stress effects for them.
TFA are produced from either industry or ruminants, and their level is usually close to zero in mammalian membranes. However, the increase of TFA in cultured cells or in tissues is an indicator of something wrong happening in cell metabolism, as mammalian cells cannot synthesize TFA through their enzymatic activity.
Several publications have shown that the radical stress deriving from sulphur metabolism is one of the causes of double bond isomerization in the lipid bilayer. Sulphur radicals are able to isomerize fatty acid double bonds from the cis to the trans configuration, thus changing the biophysical properties of the fatty acid and of the overall membrane.
In the panel of fatty acids analyzed in Report there are currently two trans fats, i.e. t16_1n7 (Palmitelaidic Acid) and t18_1n9 (Elaidic Acid), which are fundamental intra-membrane biosensors. They detect the presence of radical stress deriving from sulphur metabolism, as well as tricky metabolism anomalies.