title: Effect of weight loss on serum pigment epithelium-derived factor levels.
abstract: BACKGROUND
  Cumulating evidence suggests that the broadly acting neurotrophic pigment epithelium-derived factor is associated with visceral adiposity, the metabolic syndrome, diabetes and exerts beneficial effects on atherosclerosis. To further elucidate the relationship between pigment epithelium-derived factor and metabolic perturbations characteristic of obesity, we examined the effect of pronounced weight loss on serum levels of pigment epithelium-derived factor.
  
  
  METHODS
  Thirty-six severely obese adults were examined before and 18 months after bariatric surgery. Abdominal fat distribution was determined by ultrasound, metabolic parameters by standard methods, pro-inflammatory biomarkers and serum pigment epithelium-derived factor levels by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Bariatric surgery resulted in a mean body mass index (BMI) reduction of 9·0 ± 5·0 kg m(-2) and concomitant improvements in glucose homoeostasis and lipid profile. Pigment epithelium-derived factor serum levels decreased from a median 11·0 μg mL(-1) (interquartile range: 3·8) to 9·2 μg mL(-1) (interquartile range: 4·5) (P < 0·0001). In univariate analysis, relative change in pigment epithelium-derived factor levels was significantly associated with change in weight, BMI, fat mass, visceral fat diameter, insulin, homoeostasis model for insulin resistance, triglyceride and leptin levels (all r > 0·370, P < 0·05). No associations were observed for C-reactive protein, interleukin-6 or tumour necrosis factor alpha. After adjustment for age, sex and smoking status, associations remained significant.
  
  
  CONCLUSIONS
  The beneficial effects of bariatric surgery-induced pronounced weight loss on glucose homoeostasis may partially be attributable to visceral adipose tissue reduction and concomitantly decreasing pigment epithelium-derived factor concentrations.
authors.affiliation: Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tschoner
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Sturm
authors.forename: Claudia
authors.initials: C
authors.lastname: Ress
authors.forename: Julia
authors.initials: J
authors.lastname: Engl
authors.forename: Susanne
authors.initials: S
authors.lastname: Kaser
authors.forename: Markus
authors.initials: M
authors.lastname: Laimer
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Laimer
authors.forename: Alexander
authors.initials: A
authors.lastname: Klaus
authors.forename: Herbert
authors.initials: H
authors.lastname: Tilg
authors.forename: Josef R
authors.initials: JR
authors.lastname: Patsch
authors.forename: Christoph F
authors.initials: CF
authors.lastname: Ebenbichler
mesh_terms: D000328:Adult; D050110:Bariatric Surgery / Q000379:methods*; D001823:Body Composition; D015992:Body Mass Index; D005136:Eye Proteins / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009414:Nerve Growth Factors / Q000097:blood*; D009765:Obesity / Q000601:surgery*; D012044:Regression Analysis; D015843:Serpins / Q000097:blood*; D013997:Time Factors; D015431:Weight Loss; D055815:Young Adult; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D005136:Eye Proteins; D009414:Nerve Growth Factors; D015843:Serpins; D000099174:Pigment Epithelium-Derived Factor