title: Effects of fatiguing jumping exercise on mRNA expression of titin-complex proteins and calpains.
abstract: Eccentric exercise induced by electrostimulation increases mRNA expression of titin-complex proteins in rodent skeletal muscle. In this study, mRNA expression of titin, muscle LIM protein (MLP), cardiac ankyrin repeat protein (CARP), ankyrin repeat domain protein 2 (Ankrd2), diabetes-related ankyrin repeat protein (DARP), and calcium-activated proteinases, calpains, were investigated in human skeletal muscle after fatiguing jumping exercise. Fatiguing jumping exercise did not change mRNA expression of titin, DARP, calpain 1, or calpain 3. MLP, Ankrd2 and calpain 2 mRNA levels were increased 2 days postexercise. CARP mRNA level was already elevated 30 min and remained elevated 2 days postexercise. Increased mRNA expression of MLP, CARP, and Ankrd2, observed for the first time in human skeletal muscle, may be part of the signaling activated by physical exercise. The rapid increase in the level of CARP mRNA nominates CARP as one of the first genes to respond to exercise. The increase in the mRNA level of calpain 2 suggests its involvement in myofiber remodeling after strenuous jumping exercise.
authors.affiliation: LIKES Research Center, Rautpohjankatu 8, FIN-40700 Jyväskylä, Finland. maarit.lehti@likes.fi
authors.forename: Maarit
authors.initials: M
authors.lastname: Lehti
authors.forename: Riikka
authors.initials: R
authors.lastname: Kivelä
authors.forename: Paavo
authors.initials: P
authors.lastname: Komi
authors.forename: Jyrki
authors.initials: J
authors.lastname: Komulainen
authors.forename: Heikki
authors.initials: H
authors.lastname: Kainulainen
authors.forename: Heikki
authors.initials: H
authors.lastname: Kyröläinen
mesh_terms: D000328:Adult; D017089:Ankyrin Repeat; D001696:Biomechanical Phenomena; D002154:Calpain / Q000096:biosynthesis*; D064211:Connectin; D004591:Electrophoresis, Polyacrylamide Gel; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018763:Muscle Fatigue / Q000502:physiology*; D009124:Muscle Proteins / Q000096:biosynthesis*; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology; D011494:Protein Kinases / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D013314:Stress, Mechanical; D013848:Thigh / Q000502:physiology; D055815:Young Adult
chemical_list: D064211:Connectin; D009124:Muscle Proteins; D012333:RNA, Messenger; C577285:TTN protein, human; D011494:Protein Kinases; D002154:Calpain