Effect of high-intensity exercise on interleukin-15 expression in rabbit synovia.

The objective of this study was to examine the effect of high-intensity exercise on interleukin-15 (IL-15) expression in rabbit synovia. We utilized 24 New Zealand white rabbits, which were randomly divided equally into high-intensity exercise and control groups. The former were forced to run for 60 min/day over 4 weeks at the speed of 30 m/min. The histological changes of cartilage and knee joint synovia were investigated with hematoxylin and eosin staining. Immunohistochemistry and enzyme-linked immunosorbent assays were performed to measure IL-15 expression. From these analyses, we identified knee articular cartilage damage and synovitis in the high-intensity exercise group. This group also exhibited higher IL-15 expression in their synovial fluid and tissues than was observed in the control group (P < 0.05). These results suggested that high-intensity exercise might lead to synovitis and articular cartilage damage, and that IL-15 overexpression in synovia might be associated with post-traumatic osteoarthritis.

Effects of high intensity exhaustive exercise on SOD, MDA, and NO levels in rats with knee osteoarthritis.

The aim of this study was to investigate the impact of high intensity exhaustive exercise on nitric oxide (NO), malondialdehyde (MDA), and superoxide dismutase (SOD) expression in rats with knee osteoarthritis. Sprague Dawley rats were randomly divided into control (N = 5) and model (N = 35) groups; the model group was further divided into quiet (N = 5), low- (N = 15) and high- (N = 15) intensity exhaustive exercise groups. The low- and high-intensity groups were randomly divided into pre-exercise (N = 5), immediate post-exercise (N = 5), and 24-h post-exercise (N = 5) groups according to different time points for detection. NO, MDA, and SOD levels were compared between each group. The SOD levels in the quiet, low-, and high-intensity exhaustive exercise groups were lower than that in the control group, whereas the NO and MDA levels were higher in the former groups than in the controls (P < 0.05). The SOD level in the 24-h post-low intensity exhaustive exercise group was higher than that in the 24-h post-high intensity exhaustive exercise group, whereas the NO and MDA levels were lower in the 24-h post-low intensity than in the post-high intensity exercise group (P < 0.05). Overall, the results demonstrated that with the increase of exercise intensity, the SOD activity in the rats with knee osteoarthritis decreased gradually, whereas the MDA and NO levels gradually increased. Thus, the greater the exercise intensity, the more serious the impact on knee osteoarthritis.

Protective effect and mechanism of probucol in the treatment of spinal cord injury.

To investigate the effects of probucol on the treatment of spinal cord injury in rat, 80 rats were randomly divided into two groups of 40: a group treated with probucol and a control group. Allen's method was used to establish a rat model of spinal cord injury. After establishment, probucol (500 mg·kg(-1)·day(-1)) was intraperitoneally injected into the treatment group rats for 1 week, while the same amount of saline was used to treat the control group. On days 1, 7, 14, 21, and 28 after treatment, the function of rats' spinal cord was evaluated according to the Bresnahan locomotor rating scale. Serum protein and mRNA levels of the cytokines [interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and interleukin (IL)-17] were measured using enzyme-linked immunosorbent assay and quantitative polymerase chain reaction, respectively. Protein levels of IFN-γ, TNF-α, IL-17, and the downstream markers signal transducer and activator of transcription (STAT)-1 and STAT-3 were measured using western blot. In addition, the oxidative stress-related parameters, superoxide dismutase (SOD) and malondialdehyde (MDA), were also measured. It was found that compared to control group, rats from the treatment group had significantly lower levels of IFN-γ, TNF-α, and IL-17 (P < 0.05) on days 1 and 7, as well as lower MDA levels and higher SOD activity on days 7, 21, and 28 (P < 0.05). In summary, probucol improved the recovery of locomotion function after spinal cord injury in rats through downregulation of inflammation and upregulation of anti-oxidative activity.

Polymorphism analysis of the intron one of insulin-like growth factor 2 receptor gene (IGF2R) in FFRC strain common carp (Cyprinus carpio L.) and its relationship with growth performance.

The insulin-like growth factor 2 receptor gene (IGF2R) encodes a transmembrane protein receptor and acts to sequester and degrade excess circulating insulin-like growth factor 2, which is critical for normal mammalian growth and development. Thus, IGF2R may serve as a candidate gene underlying growth trait in the common carp. In this study, we isolated the intron one of common carp IGF2R and detected the diversity in 3 continuous generations of FFRC strain common carp. A total of 8 loci were detected within this region, which were named in accordance with their location (i.e., Loc84, Loc106, Loc119, Loc130, Loc145, Loc163, Loc167, and Loc265). Loc106, Loc119, and Loc145 were moderately polymorphic; while Loc84, Loc130, Loc163, Loc167, and Loc265 exhibited slight level of polymorphism. However, significant differences between polymorphism information content values were not observed among the different generations. For Loc145, all generations deviated from Hardy-Weinberg equilibrium. The total number of significant linkage disequilibria for all generations equaled 40. Among them, 4 pairs were detected in each population, while 8 pairs were found in the 2nd and 3rd generations. For Loc130, the G/T genotype exhibited higher body weight when compared to that of the G/G genotype. The frequency of the homozygous G/G genotype reached 87.96%; thus, we can improve FFRC strain common carp growth performance by increasing the percentage of the G/T genotype within a breeding population. Therefore, the G/T genotype could be used as a molecular marker for superior growth traits.