title: Effects of physical exercise on the P38MAPK/REDD1/14-3-3 pathways in the myocardium of diet-induced obesity rats.
abstract: Obesity is associated with myocardial insulin resistance and impairment of the mammalian target of rapamycin (mTOR) signaling pathway. The activation of the mTOR cascade by exercise has been largely shown in skeletal muscle, but insufficiently analyzed in myocardial tissue. In addition, little is known regarding the mTOR upstream molecules in the hearts of obese animals and even less about the role of exercise in this process. Thus, the present study was aimed to evaluate the effects of physical exercise on P38 Mitogen-Activated Protein Kinase (P38MAPK) phosphorylation and the REDD1 (regulated in development and DNA damage responses 1) and 14-3-3 protein levels in the myocardium of diet-induced obesity (DIO) rats. After achievement of DIO and insulin resistance, Wistar rats were divided in 2 groups: sedentary obese rats and obese rats performed treadmill running (50-min/day, 5 days per week velocity of 1.0 km/h for 2 months). Forty-eight hours after the final physical exercise, the rats were killed, and the myocardial tissue was removed for Western blot analysis. DIO increased the REDD1 protein levels and reduced the 14-3-3 protein levels and P38MAPK, mTOR, P70S6k (p70 ribosomal S6 protein kinase), and 4EBP1 (4E-binding protein-1) phosphorylation. Interestingly, physical exercise reduced the REDD1 protein levels and increased the 14-3-3 protein levels and P38MAPK, mTOR, P70S6k, and 4EBP1 phosphorylation. Moreover, exercise increased the REDD1/14-3-3 association in the heart. Our results indicate that the phospho-P38MAPK, REDD1, and 14-3-3 protein levels were reduced in the myocardium of obese rats and that physical exercise increased the protein levels of these molecules.
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: B L S
authors.initials: BL
authors.lastname: Pieri
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: D R
authors.initials: DR
authors.lastname: Souza
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: T F
authors.initials: TF
authors.lastname: Luciano
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: S O
authors.initials: SO
authors.lastname: Marques
authors.affiliation: Faculty of Applied Sciences, University of Campinas - UNICAMP, Limeira, São Paulo, Brazil.
authors.forename: J R
authors.initials: JR
authors.lastname: Pauli
authors.affiliation: School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo, Brazil.
authors.forename: A S R
authors.initials: AS
authors.lastname: Silva
authors.affiliation: Faculty of Applied Sciences, University of Campinas - UNICAMP, Limeira, São Paulo, Brazil.
authors.forename: E R
authors.initials: ER
authors.lastname: Ropelle
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: R A
authors.initials: RA
authors.lastname: Pinho
authors.affiliation: Immunometabolism Research Group, Department of Physical Education, Universidade Estadual Paulista, UNESP, Presidente Prudente, São Paulo, Brazil.
authors.forename: F S
authors.initials: FS
authors.lastname: Lira
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: C T
authors.initials: CT
authors.lastname: De Souza
mesh_terms: D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D059305:Diet, High-Fat / Q000009:adverse effects; D005081:Exercise Therapy; D006801:Humans; D007328:Insulin / Q000378:metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D009765:Obesity / Q000209:etiology / Q000235:genetics / Q000378:metabolism* / Q000628:therapy*; D051381:Rats; D017208:Rats, Wistar / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*
chemical_list: D048948:14-3-3 Proteins; C000632146:Ddit4 protein, rat; D007328:Insulin; D012097:Repressor Proteins; D014157:Transcription Factors; C546845:mTOR protein, rat; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D058570:TOR Serine-Threonine Kinases; D048051:p38 Mitogen-Activated Protein Kinases