title: Muscle contractile activity regulates Sirt3 protein expression in rat skeletal muscles.
abstract: Sirt3, a member of the sirtuin family, is known to control cellular mitochondrial function. Furthermore, because sirtuins require NAD for their deacetylase activity, nicotinamide phosphoribosyltransferase (Nampt), which is a rate-limiting enzyme in the intracellular NAD biosynthetic pathway, influences their activity. We examined the effects of exercise training and normal postural contractile activity on Sirt3 and Nampt protein expression in rat skeletal muscles. Male rats were trained by treadmill running at 20 m/min, 60 min/day, 7 days/wk for 4 wk. This treadmill training program increased the Sirt3 protein expression in the soleus and plantaris muscles by 49% and 41%, respectively (P < 0.05). Moreover, a 4-wk voluntary wheel-running program also induced 66% and 95% increases in Sirt3 protein in the plantaris and triceps muscles of rats, respectively (P < 0.05). Treadmill-running and voluntary running training induced no significant changes in Nampt protein expression in skeletal muscles. In resting rats, the soleus muscle, which is recruited during normal postural activity, possessed the greatest expression levels of the Sirt3 and Nampt proteins, followed by the plantaris and triceps muscles. Furthermore, the Sirt3, but not Nampt, protein level was reduced in the soleus muscles from immobilized hindlimbs compared with that shown in the contralateral control muscle. These results demonstrated that 1) Sirt3 protein expression is upregulated by exercise training in skeletal muscles and 2) local postural contractile activity plays an important role in maintaining a high level of Sirt3 protein expression in postural muscle.
authors.affiliation: Dept. of Health and Nutrition, Niigata Univ. of Health and Welfare, Niigata, 1398 Shimami-cho, Niigata City, Niigata 950-3198, Japan.
authors.forename: Fumi
authors.initials: F
authors.lastname: Hokari
authors.forename: Emi
authors.initials: E
authors.lastname: Kawasaki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakai
authors.forename: Keiichi
authors.initials: K
authors.lastname: Koshinaka
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Sakuma
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kawanaka
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D001835:Body Weight; D051545:Cyclooxygenase 1 / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D002149:Energy Intake; D019417:Hindlimb Suspension; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism*; D054409:Nicotinamide Phosphoribosyltransferase / Q000235:genetics / Q000378:metabolism; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D010807:Physical Endurance; D011187:Posture; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D056564:Sirtuin 1 / Q000235:genetics / Q000378:metabolism; D056566:Sirtuin 3 / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D016207:Cytokines; D008565:Membrane Proteins; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C501429:Ppargc1a protein, rat; D012333:RNA, Messenger; D014157:Transcription Factors; D051545:Cyclooxygenase 1; C496513:Ptgs1 protein, rat; D054409:Nicotinamide Phosphoribosyltransferase; C504970:nicotinamide phosphoribosyltransferase, rat; C488368:Sirt1 protein, rat; D056564:Sirtuin 1; D056566:Sirtuin 3