title: Training, leptin receptors and SOCS3 in human muscle.
abstract: Endurance exercise induces SUPPRESSOR of CYTOKINE SIGNALING 3 (SOCS3) mRNA expression in rodent skeletal muscle and endurance training overimposed on strength training blunts the hypertrophic response to strength training by an unknown mechanism. The aim of this study was to determine the effects of a concurrent strength and endurance training on fat mass, serum leptin concentration, muscle morphology, and muscle vastus lateralis leptin receptors (OB-Rb) and SOCS3 protein expression. 16 healthy young men were assigned to a control (C; n=7), and to a 12-week weightlifting (3 sessions/week)+endurance training program (T; n=9) group. Training enhanced maximal dynamic strength in lower and upper body exercises (18-54%), reduced fat mass by 1.8 kg and serum leptin concentration per kg of fat mass, and elicited muscle hypertrophy of type 2 (+18.5%, P<0.05) but not of type 1 muscle fibres (+4.6%, P=NS). No significant changes were observed in either OB-Rb or SOCS3 protein expression with training. In conclusion, concurrent strength and endurance training reduces fat mass and serum leptin and the ratio leptin/fat mass without significant effects on vastus lateralis OB-Rb protein expression. Training does not increase the basal expression of SOCS3 protein in humans.
authors.affiliation: University of Las Palmas de Gran Canaria, Department of Physical Education, Las Palmas de Gran Canaria, Spain.
authors.forename: H
authors.initials: H
authors.lastname: Olmedillas
authors.forename: B
authors.initials: B
authors.lastname: Guerra
authors.forename: A
authors.initials: A
authors.lastname: Guadalupe-Grau
authors.forename: A
authors.initials: A
authors.lastname: Santana
authors.forename: T
authors.initials: T
authors.lastname: Fuentes
authors.forename: C
authors.initials: C
authors.lastname: Dorado
authors.forename: J A
authors.initials: JA
authors.lastname: Serrano-Sanchez
authors.forename: J A L
authors.initials: JA
authors.lastname: Calbet
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger; D054411:Receptors, Leptin / Q000378:metabolism*; D013030:Spain; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000378:metabolism*; D014891:Weight Lifting / Q000502:physiology
chemical_list: D012333:RNA, Messenger; D054411:Receptors, Leptin; C106644:SOCS3 protein, human; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins