title: Ectopic and serum lipid levels are positively associated with bone marrow fat in obesity.
abstract: OBJECTIVE
  To investigate the associations between ectopic and serum lipid levels and bone marrow fat, as a marker of stem cell differentiation, in young obese men and women, with the hypothesis that ectopic and serum lipid levels would be positively associated with bone marrow fat.
  
  
  METHODS
  The study was institutional review board approved and complied with HIPAA guidelines. Written informed consent was obtained. The study group comprised 106 healthy young men and women (mean age, 33.7 years ± 6.8 [standard deviation]; range, 19-45 years; mean body mass index (BMI), 33.1 kg/m(2) ± 7.1; range, 18.1-48.8 kg/m(2)) who underwent hydrogen 1((1)H) magnetic resonance (MR) spectroscopy by using a point-resolved spatially localized spectroscopy sequence at 3.0 T of L4 for bone marrow fat content, of soleus muscle for intramyocellular lipids (IMCL), and liver for intrahepatic lipids (IHL), serum cholesterol level, serum triglyceride level, and measures of insulin resistance (IR). Exercise status was assessed with the Paffenbarger activity questionnaire.
  
  
  RESULTS
  There was a positive correlation between bone marrow fat and IHL (r = 0.21, P = .048), IMCL (r = 0.27, P = .02), and serum triglyceride level (r = 0.33, P = .001), independent of BMI, age, IR, and exercise status (P < .05). High-density lipoprotein cholesterol levels were inversely associated with bone marrow fat content, independent of BMI, age, IR, and exercise status (r = -0.21, P = .019).
  
  
  CONCLUSIONS
  Results of this study suggest that ectopic and serum lipid levels are positively associated with bone marrow fat in obese men and women.
authors.affiliation: Department of Radiology and Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Yawkey 6E, 55 Fruit St, Boston, MA 02114.
authors.forename: Miriam A
authors.initials: MA
authors.lastname: Bredella
authors.forename: Corey M
authors.initials: CM
authors.lastname: Gill
authors.forename: Anu V
authors.initials: AV
authors.lastname: Gerweck
authors.forename: Melissa G
authors.initials: MG
authors.lastname: Landa
authors.forename: Vidhya
authors.initials: V
authors.lastname: Kumar
authors.forename: Scott M
authors.initials: SM
authors.lastname: Daley
authors.forename: Martin
authors.initials: M
authors.lastname: Torriani
authors.forename: Karen K
authors.initials: KK
authors.lastname: Miller
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D015992:Body Mass Index; D001853:Bone Marrow / Q000737:chemistry*; D015444:Exercise; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008055:Lipids / Q000032:analysis* / Q000097:blood; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism*; D011795:Surveys and Questionnaires
chemical_list: D015415:Biomarkers; D008055:Lipids