Fig 1.
Biosynthetic pathways for the formation of three positional isomers of the hexadecenoic fatty acid family (C16 MUFA).
The formation of 9cis-16:1 (palmitoleic acid) occurs from palmitic acid via delta-9 desaturase (SCD-16) and from vaccenic acid via beta-oxidation. The formation of 6cis-16:1 (sapienic acid) occurs from palmitic acid (via delta-6 desaturase, D6D) and the formation of 7cis-16:1 occurs from oleic acid via beta oxidation. Oleic acid is obtained from stearic acid (18:0) via delta-9 desaturase (SCD-18).
Table 1.
Main fatty acid residues of the erythrocyte membrane phospholipids of lean healthy controls and morbidly obese subjects.
Table 2.
Main fatty acid residues of plasma cholesteryl esters in lean healthy controls and morbidly obese subjects.
Fig 2.
Comparison of the sapienic and palmitoleic acid contents (μmol/mL) in RBC membrane PL (A) and plasma CE (B).
Significant increases of palmitoleic and sapienic acids are found in PL of morbidly obese subjects compared to controls (both with p < 0.0001), whereas sapienic acid is diminished in CE of morbidly obese subjects (with p < 0.0001), with an opposite trend compared to palmitoleic acid (p ≤ 0.05). Values and error bars (SEM) are reported in Tables 1 and 2.
Table 3.
Some of the fatty acid trends to increase (↑) or decrease (↓) for morbidly obese subjects, as compared with lean healthy individuals, in RBC membrane PL and plasma CE.
Table 4.
Enzymatic indexes obtained from the quantities of the corresponding fatty acids in molar percentages (%mol) presented in S2 and S4 Tables.