title: Non-hematopoietic effects of endogenous erythropoietin on lean mass and body weight regulation.
abstract: To investigate the concurrent relationships between human plasma erythropoietin concentrations and energy expenditure (EE), body composition, plasma leptin concentrations, and associations with weight change.
  
  
  
  Plasma to measure erythropoietin and leptin; data for body composition; 24-h EE measured in a whole-room calorimeter; and 75 g oral glucose tolerance testing were available from 109 full-heritage Pima Indians (55% male) from a larger study designed to understand the causes of obesity. Seventy-nine subjects had data for weight at a later visit (mean follow-up = 4.3 ± 1.9 years) to calculate percent weight change per year.
  
  
  
  Erythropoietin, adjusted for covariates, correlated with 24-h EE (r = 0.26, P = 0.007), sleeping EE (r = 0.29, P = 0.003), fat-free mass (r = 0.19, P = 0.05), and fat mass (r = 0.27, P = 0.005), but not insulin or glucose measures. The association of erythropoietin with 24-h EE was fully mediated by fat-free mass. Erythropoietin associated with leptin in women (ρ = 0.36, P = 0.01), but not in men (P = 0.9), independently from fat mass. The association of erythropoietin with percent weight change per year was in opposing directions (interaction: P = 0.002) in males (r = -0.35, P = 0.02) versus females (r = 0.37, P = 0.02).
  
  
  
  Non-hematopoietic endogenous erythropoietin action may be involved in body weight regulation in opposing directions in men and women, i.e., weight loss in men and weight gain in women.
authors.affiliation: Obesity and Diabetes Clinical Research Section, Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, Arizona, USA.|Department of Diagnostic and Interventional Radiology, University of Leipzig, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Reinhardt
authors.affiliation: Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Soumyadeep
authors.initials: S
authors.lastname: Dey
authors.affiliation: Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Constance
authors.initials: C
authors.lastname: Tom Noguchi
authors.affiliation: Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Obesity and Diabetes Clinical Research Section, Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, Arizona, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Krakoff
authors.affiliation: Obesity and Diabetes Clinical Research Section, Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, Arizona, USA.
authors.forename: Marie S
authors.initials: MS
authors.lastname: Thearle
mesh_terms: D000293:Adolescent; D000328:Adult; D001823:Body Composition / Q000502:physiology*; D001835:Body Weight / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D004921:Erythropoietin / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007198:Indians, North American; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood; D012737:Sex Factors; D055815:Young Adult
chemical_list: C554270:EPO protein, human; D007328:Insulin; D020738:Leptin; D004921:Erythropoietin