title: Effect of obesity and metabolic syndrome on plasma oxysterols and fatty acids in human.
abstract: BACKGROUND
  Obesity and the related entity metabolic syndrome are characterized by altered lipid metabolism and associated with increased morbidity risk for cardiovascular disease and cancer. Oxysterols belong to a large family of cholesterol-derived molecules known to play crucial role in many signaling pathways underlying several diseases. Little is known on the potential effect of obesity and metabolic syndrome on oxysterols in human.
  
  
  OBJECTIVE
  In this work, we questioned whether circulating oxysterols might be significantly altered in obese patients and in patients with metabolic syndrome. We also tested the potential correlation between circulating oxysterols and fatty acids.
  
  
  METHODS
  60 obese patients and 75 patients with metabolic syndrome were enrolled in the study along with 210 age- and sex-matched healthy subjects, used as control group. Plasma oxysterols were analyzed by isotope dilution GC/MS, and plasma fatty acids profiling was assessed by gas chromatography coupled with flame ionization detection.
  
  
  RESULTS
  We found considerable differences in oxysterols profiling in the two disease groups that were gender-related. Compared to controls, males showed significant differences only in 4α- and 4β-hydroxycholesterol levels in obese and metabolic syndrome patients. In contrast, females showed consistent differences in 7-oxocholesterol, 4α-hydroxycholesterol, 25-hydroxycholesterol and triol. Concerning fatty acids, we found minor differences in the levels of these variables in males of the three groups. Significant changes were observed in plasma fatty acid profile of female patients with obesity or metabolic syndrome. We found significant correlations between various oxysterols and fatty acids. In particular, 4β-hydroxycholesterol, which is reduced in obesity and metabolic syndrome, correlated with a number of saturated and mono-unsaturated fatty acids that are end-products of de novo lipogenesis.
  
  
  CONCLUSIONS
  Our data provide the first evidence that obesity and metabolic syndrome are associated with major, gender-specific, changes in circulating oxysterols and fatty acids. These findings suggest a metabolic link between oxysterols and fatty acids, and that oxysterols may contribute to the epidemic diseases associated with obesity and metabolic syndrome in female.
authors.affiliation: INRA, ToxAlim UMR1331 (Research Centre in Food Toxicology), Toulouse, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Tremblay-Franco
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Zerbinati
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pacelli
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Palmaccio
authors.affiliation: Department of Experimental Medicine, Sapienza University, Rome, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Lubrano
authors.affiliation: INRA, ToxAlim UMR1331 (Research Centre in Food Toxicology), Toulouse, France.
authors.forename: Simon
authors.initials: S
authors.lastname: Ducheix
authors.affiliation: INRA, ToxAlim UMR1331 (Research Centre in Food Toxicology), Toulouse, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Guillou
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy. Electronic address: luigi.iuliano@uniroma1.it.
authors.forename: Luigi
authors.initials: L
authors.lastname: Iuliano
mesh_terms: D000328:Adult; D002784:Cholesterol / Q000097:blood; D016000:Cluster Analysis; D003710:Demography; D005227:Fatty Acids / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000150:complications*; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000150:complications*; D010084:Oxidation-Reduction; D013261:Sterols / Q000097:blood*
chemical_list: D005227:Fatty Acids; D013261:Sterols; D002784:Cholesterol
keywords: Diabetes; Fatty acids; Lipid metabolism; Metabolic syndrome; Obesity; Oxysterols