title: Altered levels of serum sphingomyelin and ceramide containing distinct acyl chains in young obese adults.
abstract: OBJECTIVE
  Recent studies indicate that sphingolipids, sphingomyelin (SM) and ceramide (Cer) are associated with the development of metabolic syndrome. However, detailed profiles of serum sphingolipids in the pathogenesis of this syndrome are lacking. Here we have investigated the relationship between the molecular species of sphingolipids in serum and the clinical features of metabolic syndrome, such as obesity, insulin resistance, fatty liver disease and atherogenic dyslipidemia.
  
  
  METHODS
  We collected serum from obese (body mass index, BMI⩾35, n=12) and control (BMI=20-22, n=11) volunteers (18-27 years old), measured the levels of molecular species of SM and Cer in the serum by liquid chromatography-mass spectrometry and analyzed the parameters for insulin resistance, liver function and lipid metabolism by biochemical blood test.
  
  
  RESULTS
  The SM C18:0 and C24:0 levels were higher, and the C20:0 and C22:0 levels tended to be higher in the obese group than in the control group. SM C18:0, C20:0, C22:0 and C24:0 significantly correlated with the parameters for obesity, insulin resistance, liver function and lipid metabolism, respectively. In addition, some Cer species tended to correlate with these parameters. However, SM species containing unsaturated acyl chains and most of the Cer species were not associated with these parameters.
  
  
  CONCLUSIONS
  The present results demonstrate that the high levels of serum SM species with distinct saturated acyl chains (C18:0, C20:0, C22:0 and C24:0) closely correlate with the parameters of obesity, insulin resistance, liver function and lipid metabolism, suggesting that these SM species are associated with the development of metabolic syndrome and serve as novel biomarkers of metabolic syndrome and its associated diseases.
authors.affiliation: Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hanamatsu
authors.affiliation: 1] Department of Gastroenterology and Hepatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan [2] Health Care Center, Hokkaido University, Sapporo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ohnishi
authors.affiliation: Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, Sapporo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Sakai
authors.affiliation: Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, Sapporo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yuyama
authors.affiliation: 1] Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, Sapporo, Japan [2] Department of Applied Biochemistry and Food Science, Faculty of Agriculture, Saga University, Saga, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Mitsutake
authors.affiliation: Laboratory of Pathophysiology and Therapeutics, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Takeda
authors.affiliation: Health Care Center, Hokkaido University, Sapporo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hashino
authors.affiliation: Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, Sapporo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Igarashi