Objective To explore the effects of nerve growth factor (NGF) and low frequency electricity stimulus on the configurations of skeletal muscle cells and the change of muscle fibre types in the denervated skeletal muscle separately.Methods The denervated rat model was established and model animals were injected with the NGF and given the stimulus (frequency=2 Hz) about 30 days. The configurations and the change of muscle fibre types were observed by immunohistochemistry and image analysis.Results The muscle fibre was in chaos and the boundary was not obvious among cells in the denervated rats; the muscle fibre of the denervated rats with NGF injection and low frequency electricity stimulus was more regular and the boundary of cells was clearer, the cells number was more than those of the denervated rats. Compared to normal rats, the proportion of Ⅰ muscle fibre in the denervated rats increased ( P<0.05), whereas the proportion of Ⅱ muscle fibre decreased ( P<0.05); it had no significant differences of the two types of muscle fibre between the denervated rats with NGF injection, low frequency electricity stimulus and the denervated rats ( P<0.05).Conclusion NGF injection and low frequency electricity stimulus can make the configurations of denervated muscle to better.

Objective To investigate the effect and mechanisms of factor fibroblast growth factor inducible 14(Fn14)in the high glucose induced-cardiomyocyte hypertrophy. Method To observe the expression of collagenⅠ, connective tissue growth factor ( CTGF ) , transforming growth factor-β1 ( TGF-β1 ) , and Fn14 in high glucose induced-cardiomyocyte hypertrophy. Fn14 expressions was down-regulated by siRNA interference technique, and then the expressions of collagen Ⅰ, CTGF, and TGF-β1 were observed, and the mechanism was also explored. Results The expression of collagen I, CTGF and TGF-β1 was significantly up-regulated after high glucose induced-cardiomyocyte hypertrophy for 72 h. At the same time, the expression of Fn14 was increased after 72 h-treatment, and reached the peak at concentration of 30 mmol/L high glucose. High glucose could not up-regulated the expression of collagenⅠ, CTGF, and TGF-β1 after siFn14 interference, while the same result was observed in the expression of p-JNK. Conclusion The expressions of collagenⅠ, CTGF, TGF-β1, and Fn14 in cardiomyocyte of neonatal rats were induced by high glucose. While Fn14 expression was inhibited, the expressions of collagenⅠ, CTGF, and TGF-β1 were down-regulated, which seems to be involved with p-JNK signaling pathway.

BACKGROUND:There are many postmenopausal women taking hormone, which leads to much loss of bone mass, further inducing fragility fractures. The studies on the hormone exposure combined with ovariectomy-induced osteoporotic model are still immature, and the related molecular mechanism remains unclear. OBJECTIVE: To establish the rat osteoporotic model induced by ovariectomy combined with glucocorticoid exposure and to explore the underlying molecular mechanism. METHODS: Thirty 3-month-old female Sprague-Dawley rats were randomly divided into blank control, sham and model groups (n=10 per group). The rats in the blank control group received no intervention; rats in the sham group were clipped off a little of coeliac adipose tissue; the model rats received bilateral ovariectomy and 4-week administration of glucocorticoid. RESULTS AND CONCLUSION:At 4 weeks after modeling, compared with blank control and sham groups, the model group showed significantly lower bone mineral density of the femur, number of bone trabeculae and bone volume/total volume, and significantly wider bone trabecular spacing. Additionally, the model group revealed the damaged bone trabecular structure and thiner cortical bone. The expression level of Runx2 was downregulated whereas both collagen type 1α1 and peroxisome proliferators activated receptor γ mRNA were upregulated in the model group. These findings suggest that ovariectomized rats exposed to glucocorticoid rapidly develop femur osteoporosis, maybe by downregulating the expression of Runx2, as well as upregualting collagen type 1α1 and peroxisome proliferators activatedreceptor γ mRNA.

Objective:To explore the features the gait of elderly persons with type 2 diabetes and peri-pheral neuropathy.Methods:Twenty patients no less than 60 years old with type 2 diabetes and peripheral neuropathy (DPN) formed a DPN group, while 20 counterparts with type 2 diabetes but without peripheral neuropathy composed the DM group, and another 20 healthy counterparts served as a control group. The three groups were tested using the Swedish Qualisys motion capture system and their walking speed, step length, step width, stride frequency and stride length, bipedal foot support phase time, single foot support phase time, peak plantar pressure, and regional-holding time were collected and compared.Results:The average walking speed, stride length and stepping frequency of the DPN group were all significantly lower than the other 2 groups′ averages. Their bipedal support phase was significantly longer, but their single foot support phase time was significantly shorter. And in the DPN group the average first and second peak plantar pressures and the second peak pressure time were significantly greater than the other groups′ averages.Conclusions:Elderly patients with type 2 diabetes and peripheral neuropathy have significant gait abnormalities, decreased walking stability, as well as increased plantar pressure and plantar compression time.

Objective:To compare the resting energy expenditure(REE)characteristics among young men with different body mass indexes(BMI).Methods:Thirty young men[average age was(26.93± 4.16)years]were enrolled in this study.They underwent resting metabolism tests in the Department of Sports Medicine of Peking University Third Hospital from December 2017 to June 2021.The resting meta-bolic rate(RMR)was measured by indirect calorimetry,the body composition was measured by bioresis-tance antibody component analyzer.The REE characteristics were analyzed,and 11 predictive equations were used to estimate RMR and compared with the measured value.The differences were analyzed by paired t-test and intra-class correlation coefficient(ICC).Results:The RMR of the overall 30 young men was(1 960.17±463.11)kcal/d(1 kcal=4.186 8 kJ).Including(1 744.33±249.62)kcal/d in those with normal BMI,which was significantly lower than that in those who were overweight or obese[(2 104.06±520.32)kcal/d,P＜0.01],but the weight-corrected RMR in those with normal BMI was significantly higher than that in those who were overweight or obese[(24.02±2.61)kcal/(kg·d)vs.(19.98±4.38)kcal/(kg·d),P＜0.01].The RMR was significantly and positively correlated with body weight,adiposity,lean body mass,body surface area,and extracellular fluid in the subjects with diffe-rent BMI(all P＜0.05).The predicted values of the 11 prediction equations were not in good agreement with the measured values(all ICC＜0.75),with relatively high agreement between the pre-dicted and measured values of the World Health Organization(WHO)equation in overweight obese young men(ICC=0.547,P＜0.01).Conclusion:There were significant differences in RMR among young men with different BMI,and the RMR after weight correction should be considered for those who were overweight or obese.The consistency between the predicted values of different prediction equations and the actual measured values of RMR was relatively poor,and it is recommended to accurately measure RMR by indirect calorimetry.For overweight or obese young men,the WHO prediction equation can be considered to calculate RMR,but it is necessary to establish an RMR prediction equation applicable to different BMI populations.