title: Attenuated fibroblast growth factor 21 response to acute aerobic exercise in obese individuals.
abstract: OBJECTIVE
  Fibroblast growth factor 21 (FGF21) is positively associated with body mass index, potentially as a compensatory mechanism to mediate obesity related metabolic and inflammatory insult due to chronic low-grade elevations of the pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α). Therefore, FGF21 response in obese subjects and the associations with increased pro-inflammatory cytokines, insulin resistance, and energy utilization warrants investigation.
  
  
  RESULTS
  Twenty four untrained subjects (12 obese and 12 normal-weight) performed 30 min of continuous submaximal aerobic exercise. Following exercise, obese subjects exhibited a blunted FGF21 response to exercise compared to normal-weight subjects as indicated by area-under-the-curves "with respect to increase" (AUCi) analyses (p = 0.005). Furthermore, while exercise-induced plasma FGF21 was not associated with any inflammatory cytokine (IL-6 and TNF-α) response, FGF21 AUCi was positively correlated with glucose AUCi (r = 0.495, p = 0.014), total relative energy expenditure (r = 0.562, p = 0.004), and relative maximal oxygen consumption (VO2max; r = 0.646, p = 0.001) in all subjects.
  
  
  CONCLUSIONS
  Impaired cardiorespiratory fitness may influence the sensitivity of FGF21 response to acute exercise in obese individuals, potentially contributing to the attenuated metabolic response (e.g., glucose) and total exercise energy expenditure. Therefore, exercise training aimed at improving cardiorespiratory fitness and/or body composition may augment cardioprotective properties against obesity-associated CVD through enhanced FGF21 flux.
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA; Department of Kinesiology and Health Sciences, Virginia Commonwealth University, VA, USA. Electronic address: slusheral@vcu.edu.
authors.forename: A L
authors.initials: AL
authors.lastname: Slusher
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA.
authors.forename: M
authors.initials: M
authors.lastname: Whitehurst
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA.
authors.forename: R F
authors.initials: RF
authors.lastname: Zoeller
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Mock
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA.
authors.forename: M
authors.initials: M
authors.lastname: Maharaj
authors.affiliation: Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA.
authors.forename: C-J
authors.initials: CJ
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D002318:Cardiovascular Diseases / Q000097:blood / Q000517:prevention & control; D016022:Case-Control Studies; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D009765:Obesity / Q000097:blood / Q000628:therapy*; D010101:Oxygen Consumption; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055105:Waist Circumference; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007328:Insulin; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; C414620:fibroblast growth factor 21; D005346:Fibroblast Growth Factors
keywords: Energy expenditure; FGF21; Insulin resistance; Interleukin-6; Tumor necrosis factor-alpha