title: Quadriceps muscle atrophy after anterior cruciate ligament transection involves increased mRNA levels of atrogin-1, muscle ring finger 1, and myostatin.
abstract: OBJECTIVE
  The aim of this study was to assess the mRNA levels of atrogin-1, muscle ring finger 1, and myostatin in rat quadriceps after anterior cruciate ligament (ACL) transection.
  
  
  METHODS
  Wistar rats were randomized into three different groups: ACL (surgery and ACL transection), sham (surgery without ACL transection), and control. Vastus medialis, rectus femoris, and vastus lateralis muscles were harvested at 1, 2, 3, 7, and 15 days after ACL transection. The mRNA levels of atrogin-1, muscle ring finger 1, and myostatin, as well as the ubiquitinated protein content, muscle mass, and cross-sectional area of the muscle fibers, were evaluated.
  
  
  RESULTS
  Elevated levels of atrogin-1, muscle ring finger 1, and myostatin mRNA were detected in all tested muscles at most time points. The ubiquitinated protein content was increased at 3 days in the ACL and sham groups. The muscle mass of the ACL group was reduced at 3, 7, and 15 days (vastus lateralis and vastus medialis) and at 7 and 15 days (rectus femoris), whereas it was reduced in the sham group at 3 and 7 days (vastus lateralis and vastus medialis) and at 7 days (rectus femoris). The cross-sectional area of vastus medialis was reduced at 3, 7, and 15 days in the ACL group and at 3 and 7 days in the sham group. The cross-sectional area of the vastus lateralis was reduced at 7 and 15 days in the ACL group and at 7 days in the sham group. Whereas muscle mass and cross-sectional area recovery was noted in the sham group, no recovery was observed in the ACL group.
  
  
  CONCLUSIONS
  Quadriceps atrophy after ACL transection involves increased levels of myostatin, atrogin-1, and muscle ring finger 1 mRNA and the accumulation of ubiquitinated protein.
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, Brazil.
authors.forename: Gabriel B
authors.initials: GB
authors.lastname: Delfino
authors.forename: Sabrina M
authors.initials: SM
authors.lastname: Peviani
authors.forename: João L Q
authors.initials: JL
authors.lastname: Durigan
authors.forename: Thiago L
authors.initials: TL
authors.lastname: Russo
authors.forename: Igor L
authors.initials: IL
authors.lastname: Baptista
authors.forename: Mario
authors.initials: M
authors.lastname: Ferretti
authors.forename: Anselmo S
authors.initials: AS
authors.lastname: Moriscot
authors.forename: Tania F
authors.initials: TF
authors.lastname: Salvini
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D016118:Anterior Cruciate Ligament / Q000378:metabolism / Q000601:surgery*; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D004195:Disease Models, Animal; D008297:Male; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism*; D009133:Muscular Atrophy / Q000378:metabolism* / Q000473:pathology; D055435:Myostatin / Q000235:genetics / Q000378:metabolism*; D052097:Quadriceps Muscle / Q000378:metabolism* / Q000473:pathology; D054829:RING Finger Domains / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D012016:Reference Values; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics / Q000378:metabolism*; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D009124:Muscle Proteins; D055435:Myostatin; D012333:RNA, Messenger; C486692:Fbxo32 protein, rat; D044843:SKP Cullin F-Box Protein Ligases