title: Treating NAFLD in OLETF rats with vigorous-intensity interval exercise training.
abstract: BACKGROUND
  There is increasing use of high-intensity interval-type exercise training in the management of many lifestyle-related diseases.
  
  
  OBJECTIVE
  This study aimed to test the hypothesis that vigorous-intensity interval exercise is as effective as traditional moderate-intensity aerobic exercise training for nonalcoholic fatty liver disease (NAFLD) outcomes in obese, Otsuka Long-Evans Tokushima Fatty (OLETF) rats.
  
  
  METHODS
  OLETF rats (age, 20 wk; n = 8-10 per group) were assigned to sedentary (O-SED), moderate-intensity exercise training (O-MOD EX; 20 m·min(-1), 15% incline, 60 min·d(-1), 5 d·wk(-1) of treadmill running), or vigorous-intensity interval exercise training (O-VIG EX; 40 m·min(-1), 15% incline, 6 × 2.5 min bouts per day, 5 d·wk(-1) of treadmill running) groups for 12 wk.
  
  
  RESULTS
  Both MOD EX and VIG EX effectively lowered hepatic triglycerides, serum alanine aminotransferase (ALT), perivenular fibrosis, and hepatic collagen 1α1 messenger RNA (mRNA) expression (vs O-SED, P < 0.05). In addition, both interventions increased hepatic mitochondrial markers (citrate synthase activity and fatty acid oxidation) and suppressed markers of de novo lipogenesis (fatty acid synthase, acetyl coenzyme A carboxylase, Elovl fatty acid elongase 6, and steroyl CoA desaturase-1), whereas only MOD EX increased hepatic mitochondrial Beta-hydroxyacyl-CoA dehydrogenase (β-HAD) activity and hepatic triglyceride export marker apoB100 and lowered fatty acid transporter CD36 compared with O-SED. Moreover, whereas total hepatic macrophage population markers (CD68 and F4/80 mRNA) did not differ among groups, MOD EX and VIG EX lowered M1 macrophage polarization markers (CD11c, interleukin-1β, and tumor necrosis factor α mRNA) and MOD EX increased M2 macrophage marker, CD206 mRNA, compared with O-SED.
  
  
  CONCLUSIONS
  The accumulation of 15 min·d(-1) of VIG EX for 12 wk had similar effectiveness as 60 min·d(-1) of MOD EX in the management of NAFLD in OLETF rats. These findings may have important health outcome implications as we work to design better exercise training programs for patients with NAFLD.
authors.affiliation: 1Research Service-Harry S. Truman Memorial Veterans Medical Center, Columbia, MO; 2Department of Medicine, Division of Gastroenterology and Hepatology, University of Missouri, Columbia, MO; 3Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO; 4Department of Biomedical Sciences, University of Missouri, Columbia, MO; 5Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO; 6Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO; and 7Department of Medicine, Division of Endocrinology, University of Missouri, Columbia, MO.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Linden
authors.forename: Justin A
authors.initials: JA
authors.lastname: Fletcher
authors.forename: E Matthew
authors.initials: EM
authors.lastname: Morris
authors.forename: Grace M
authors.initials: GM
authors.lastname: Meers
authors.forename: M Harold
authors.initials: MH
authors.lastname: Laughlin
authors.forename: Frank W
authors.initials: FW
authors.lastname: Booth
authors.forename: James R
authors.initials: JR
authors.lastname: Sowers
authors.forename: Jamal A
authors.initials: JA
authors.lastname: Ibdah
authors.forename: John P
authors.initials: JP
authors.lastname: Thyfault
authors.forename: R Scott
authors.initials: RS
authors.lastname: Rector
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D024042:Collagen Type I / Q000378:metabolism; D004195:Disease Models, Animal; D005081:Exercise Therapy / Q000379:methods*; D006019:Glycolysis; D006321:Heart / Q000033:anatomy & histology; D008055:Lipids / Q000097:blood; D050155:Lipogenesis; D008099:Liver / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism; D065626:Non-alcoholic Fatty Liver Disease / Q000378:metabolism / Q000628:therapy*; D009929:Organ Size; D010805:Physical Conditioning, Animal; D012333:RNA, Messenger / Q000378:metabolism; D020334:Rats, Inbred OLETF; D014280:Triglycerides / Q000378:metabolism; D015431:Weight Loss
chemical_list: D001786:Blood Glucose; D024042:Collagen Type I; D008055:Lipids; D012333:RNA, Messenger; D014280:Triglycerides