title: Intensity-dependent and sex-specific alterations in hepatic triglyceride metabolism in mice following acute exercise.
abstract: Precise regulation of hepatic triglyceride (TG) metabolism and secretion is critical for health, and exercise could play a significant role. We compared one session of high-intensity interval exercise (HIIE) vs. continuous exercise (CE) on hepatic TG metabolism. Female and male mice were assigned to CE, HIIE, or sedentary control (CON). HIIE was a 30-min session of 30-s running intervals (30 m/min) interspersed with 60-s walking periods (5 m/min). CE was a distance- and duration-matched run at 13.8 m/min. Hepatic content of TG and TG secretion rates, as well as expression of relevant genes/proteins, were measured at 3 h (day 1) and 28 h (day 2) postexercise. On day 1, hepatic [TG] in CE and HIIE were both elevated vs. CON in both sexes with an approximately twofold greater elevation in HIIE vs. CE in females. In both sexes, hepatic perilipin 2 (PLIN2) protein on day 1 was increased significantly by both exercise types with a significantly greater increase with HIIE than CE, whereas the increase in mRNA reached significance only after HIIE. On day 2 in both sexes the increases in hepatic TG and PLIN2 with exercise declined toward CON levels. Only HIIE on day 2 resulted in reduced hepatic TG secretion by ∼20% in females with no effect in males. Neither exercise modality altered AMPK signaling or microsomal triglyceride transfer protein expression. Females exhibited higher hepatic TG secretion than males in association with different expression levels of related metabolic enzymes. These intensity-dependent and sex-specific alterations following exercise may have implications for sex-based exercise prescription.
authors.affiliation: Department of Exercise Science, Rutgers University, New Brunswick, New Jersey; Center for Lipid Research, Rutgers University, New Brunswick, New Jersey.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Tuazon
authors.affiliation: Department of Exercise Science, Rutgers University, New Brunswick, New Jersey; Center for Lipid Research, Rutgers University, New Brunswick, New Jersey.
authors.forename: Taylor R
authors.initials: TR
authors.lastname: McConnell
authors.affiliation: Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey; and Center for Lipid Research, Rutgers University, New Brunswick, New Jersey.
authors.forename: Gabriel J
authors.initials: GJ
authors.lastname: Wilson
authors.affiliation: Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey; and Center for Lipid Research, Rutgers University, New Brunswick, New Jersey.
authors.forename: Tracy G
authors.initials: TG
authors.lastname: Anthony
authors.affiliation: Department of Exercise Science, Rutgers University, New Brunswick, New Jersey; Center for Lipid Research, Rutgers University, New Brunswick, New Jersey ghender21@hotmail.com.
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Henderson
mesh_terms: D000263:Adenylate Kinase / Q000378:metabolism; D000818:Animals; D005260:Female; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D010101:Oxygen Consumption / Q000502:physiology; D000070780:Perilipin-2; D010766:Phosphorylation; D010805:Physical Conditioning, Animal / Q000379:methods / Q000502:physiology*; D005082:Physical Exertion; D012737:Sex Factors; D014280:Triglycerides / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D000070780:Perilipin-2; C000602983:Plin2 protein, mouse; D014280:Triglycerides; D000263:Adenylate Kinase
keywords: HIIT; gender; high-intensity interval exercise; lipoprotein; physical activity; postexercise; postexercise recovery