title: Inflammatory cytokine expression in the quadriceps of rats with posttraumatic knee stiffness: A preliminary study.
abstract: The primary purpose of this study was to investigate cytokine expression in the quadriceps of rats with posttraumatic knee stiffness (PTKS) and to determine the effect of exercise training on these cytokines at different follow-up time points. The PTKS rats were randomly assigned into two even groups. The treatment group received exercise training, while the control group received no treatment. Quadriceps specimens were harvested randomly from each group at 8, 12, 16, and 20 weeks. RT-qPCR and immunohistochemical analyses were used to assess the protein and mRNA expression levels of the cytokines IL-1, IL-2, TNF-α, COX-1, and COX-2. TNF-α immunostaining did not differ between the treated and control group tissues, whereas weak immunostaining was observed for all other cytokines in the specimens from the treatment group compared with those from the control group at approximately 12 and 20 weeks. The cytokine levels decreased at approximately 8 weeks in the treatment group, whereas these levels remained elevated or plateaued in the control group. These differences were statistically significant (p<0.05). This study demonstrated that the expression of cytokines IL-1, IL-2, COX-1, and COX-2 increased in the quadriceps of rats with PTKS and that exercise training affected the observed profile trends of these cytokines.
authors: School of Rehabilitation Medicine, Capital Medical University, Beijing, People's Republic of China; Department of Orthopedics and Rehabilitation, Beijing Charity Hospital, Beijing 100068, People's Republic of China. Electronic address: keminlqliu@sina.com.
authors: Kemin
authors: K
authors: Liu
authors: School of Rehabilitation Medicine, Capital Medical University, Beijing, People's Republic of China; Department of Orthopedics and Rehabilitation, Beijing Charity Hospital, Beijing 100068, People's Republic of China.
authors: Fei
authors: F
authors: Wang
authors: School of Rehabilitation Medicine, Capital Medical University, Beijing, People's Republic of China; Department of Orthopedics and Rehabilitation, Beijing Charity Hospital, Beijing 100068, People's Republic of China.
authors: Zhigang
authors: Z
authors: Cui
authors: School of Rehabilitation Medicine, Capital Medical University, Beijing, People's Republic of China; Department of Orthopedics and Rehabilitation, Beijing Charity Hospital, Beijing 100068, People's Republic of China.
authors: Sihai
authors: S
authors: Liu
authors: School of Rehabilitation Medicine, Capital Medical University, Beijing, People's Republic of China; Department of Orthopedics and Rehabilitation, Beijing Charity Hospital, Beijing 100068, People's Republic of China.
authors: Xinzuo
authors: X
authors: Han
mesh_terms: D000818:Animals; D051545:Cyclooxygenase 1 / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D007150:Immunohistochemistry; D018836:Inflammation Mediators / Q000378:metabolism*; D007375:Interleukin-1 / Q000378:metabolism; D007596:Joints / Q000293:injuries* / Q000473:pathology*; D008297:Male; D052097:Quadriceps Muscle / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D007375:Interleukin-1; D012333:RNA, Messenger; D051545:Cyclooxygenase 1
keywords: Cytokine; Posttraumatic knee stiffness; Quadriceps; Rat