Profile of Free Fatty Acids and Fractions of Phospholipids, Cholesterol Esters and Triglycerides in Serum of Obese Youth with and without Metabolic Syndrome

Juliana Bermúdez-Cardona,Claudia Velásquez-Rodríguez

doi:10.3390/nu8020054

Abstract

The study evaluated the profile of circulating fatty acids (FA) in obese youth with and without metabolic syndrome (MetS) to determine its association with nutritional status, lifestyle and metabolic variables. A cross-sectional study was conducted in 96 young people, divided into three groups: obese with MetS (OBMS), obese (OB) and appropriate weight (AW). FA profiles were quantified by gas chromatography; waist circumference (WC), fat folds, lipid profile, high-sensitivity C-reactive protein, glucose, insulin, the homeostasis model assessment (HOMA index), food intake and physical activity (PA) were assessed. The OBMS group had significantly greater total free fatty acids (FFAs), palmitic-16:0 in triglyceride (TG), palmitoleic-16:1n-7 in TG and phospholipid (PL); in the OB group, these FAs were higher than in the AW group. Dihomo-gamma-linolenic (DHGL-20:3n-6) was higher in the OBMS than the AW in PL and FFAs. Linoleic-18:2n-6 in TG and PL had the lowest proportion in the OBMS group. WC, PA, total FFA, linoleic-18:2n-6 in TG and DHGL-20:3n-6 in FFAs explained 62% of the HOMA value. The OB group presented some higher proportions of FA and biochemical values than the AW group. The OBMS had proportions of some FA in the TG, PL and FFA fractions that correlated with disturbances of MetS.

Highlights

Obesity is a pandemic that affects 34.3% of the adult population, generating an increase in the prevalence of chronic diseases [1]
fatty acids (FA) in the TG, PL and free FAs (FFAs) fractions that correlated with disturbances of Metabolic Syndrome (MetS)
The sample size necessary to form three groups was defined with the software Primer®, considering an alpha error of 0.05, a power of 85% and an expected minimum difference between the case and control groups in the concentrations of different FAs according to reports from other studies: Palmitic-16:0 in cholesterol esters (CE) [22] and FFAs [23]; Palmitoleic-16:1n-7 in PL, CE and TG [22,24]; Stearic-18:0 in PL [22] and FFAs [23]; and DHGL-20:3n-6 in PL [24,25] and CE [22], which indicated a number of 32 youth per group

Summary

Introduction

Obesity is a pandemic that affects 34.3% of the adult population, generating an increase in the prevalence of chronic diseases [1]. Obesity is present in youth; in 2013, the prevalence of overweight reached 22.6% in girls and 23.9% in boys in industrialized countries [2]. In states of chronic excess energy, both subcutaneous and visceral adipocytes undergo hypertrophy and saturation of their storage capacity, along with infiltration and activation of macrophages; these events result in an increased release of fatty acids (FAs) and pro-inflammatory substances, such as tumor necrosis factor (TNF)α and interleukin (IL)-6, which generates tissue dysfunction and metabolic damage [5,6]. The release of pro-inflammatory substances and free FAs (FFAs) could be the connection between central obesity and metabolic disturbances.

Objectives

Methods

Discussion

Conclusion