title: Is sprint exercise a leptin signaling mimetic in human skeletal muscle?
abstract: This study was designed to determine whether sprint exercise activates signaling cascades linked to leptin actions in human skeletal muscle and how this pattern of activation may be interfered by glucose ingestion. Muscle biopsies were obtained in 15 young healthy men in response to a 30-s sprint exercise (Wingate test) randomly distributed into two groups: the fasting (n = 7, C) and the glucose group (n = 8, G), who ingested 75 g of glucose 1 h before the Wingate test. Exercise elicited different patterns of JAK2, STAT3, STAT5, ERK1/2, p38 MAPK phosphorylation, and SOCS3 protein expression during the recovery period after glucose ingestion. Thirty minutes after the control sprint, STAT3 and ERK1/2 phosphorylation levels were augmented (both, P < 0.05). SOCS3 protein expression was increased 120 min after the control sprint but PTP1B protein expression was unaffected. Thirty and 120 min after the control sprint, STAT5 phosphorylation was augmented (P < 0.05). Glucose abolished the 30 min STAT3 and ERK1/2 phosphorylation and the 120 min SOCS3 protein expression increase while retarding the STAT5 phosphorylation response to sprint. Activation of these signaling cascades occurred despite a reduction of circulating leptin concentration after the sprint. Basal JAK2 and p38 MAPK phosphorylation levels were reduced and increased (both P < 0.05), respectively, by glucose ingestion prior to exercise. During recovery, JAK2 phosphorylation was unchanged and p38 MAPK phosphorylation was transiently reduced when the exercise was preceded by glucose ingestion. In conclusion, sprint exercise performed under fasting conditions is a leptin signaling mimetic in human skeletal muscle.
authors.affiliation: Department of Physical Education, University of Las Palmas de Gran Canaria, Spain.
authors.forename: Borja
authors.initials: B
authors.lastname: Guerra
authors.forename: Hugo
authors.initials: H
authors.lastname: Olmedillas
authors.forename: Amelia
authors.initials: A
authors.lastname: Guadalupe-Grau
authors.forename: Jesús G
authors.initials: JG
authors.lastname: Ponce-González
authors.forename: David
authors.initials: D
authors.lastname: Morales-Alamo
authors.forename: Teresa
authors.initials: T
authors.lastname: Fuentes
authors.forename: Esther
authors.initials: E
authors.lastname: Chapinal
authors.forename: Leandro
authors.initials: L
authors.lastname: Fernández-Pérez
authors.forename: Pedro
authors.initials: P
authors.lastname: De Pablos-Velasco
authors.forename: Alfredo
authors.initials: A
authors.lastname: Santana
authors.forename: Jose A L
authors.initials: JA
authors.lastname: Calbet
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001706:Biopsy; D001786:Blood Glucose / Q000378:metabolism; D004789:Enzyme Activation; D015444:Exercise; D005215:Fasting / Q000378:metabolism; D005786:Gene Expression Regulation; D005947:Glucose / Q000008:administration & dosage; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D053614:Janus Kinase 2 / Q000378:metabolism; D020738:Leptin / Q000097:blood / Q000378:metabolism*; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009119:Muscle Contraction / Q000235:genetics; D018482:Muscle, Skeletal / Q000378:metabolism*; D010766:Phosphorylation; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000378:metabolism; D012420:Running; D050796:STAT3 Transcription Factor / Q000378:metabolism; D050799:STAT5 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000378:metabolism; D013997:Time Factors; D055815:Young Adult; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D001786:Blood Glucose; C508600:IL6 protein, human; D015850:Interleukin-6; D020738:Leptin; C106644:SOCS3 protein, human; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D050799:STAT5 Transcription Factor; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D019382:Human Growth Hormone; C507924:JAK2 protein, human; D053614:Janus Kinase 2; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; C516607:PTPN1 protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D005947:Glucose