Effects of vibration on the expression of mitochondrial fusion and fission genes and ultrastructure of skeletal muscle in rabbits / 中华劳动卫生职业病杂志

Objective: To study the effects of vibration on the expression of mitochondrial fusion and fission genes and ultrastructure of skeletal muscle in rabbits. Methods: Thirty-two 3.5-month-old New Zealand rabbits were randomly divided into low-intensity group, medium-intensity group, high-intensity group and control group, with 8 rabbits in each group. The rabbits in the experimental group were subjected to hind limb vibration load test for 45 days. The vibration intensity of the high intensity group was 12.26 m/s(2), the medium intensity group was 6.13 m/s(2), and the low intensity group was 3.02 m/s(2) according to the effective value of weighted acceleration[a(hw (4))] for 4 hours of equal energy frequency. The control group was exposed to noise only in the same experimental environment as the medium-intensity group. The noise levels of each group were measured during the vibration load experiment. After the test, the mRNA expression of mitochondrial fusion gene (Mfn1/Mfn2) and fission gene (Fis1, Drp1) by RT-PCR in the skeletal muscles were measured and the ultrastructure of the skeletal muscles were observed in high intensity group. Results: The mRNA expression of mitochondrial in the skeletal muscle tissues of control group, low intensity group, medium intensity group and high intensity group were Mfn1: 3.25±1.36, 3.85±1.90, 4.53±2.31 and 11.63±7.68; Mfn2: 0.68±0.25, 1.02±0.40, 0.94±0.33 and 1.40±0.45; Fis1: 1.05±0.62, 1.15±0.59, 1.53±1.06 and 2.46±1.51 and Drp1: 3.72±1.76, 2.91±1.63, 3.27±2.01 and 4.21±2.46, respectively. Compared with the control group, the expressions of Mfn1 mRNA, Mfn2 mRNA and Fis1 mRNA in the high-intensity group increased significantly (P<0.05) , and the expressions of Mfn2 mRNA in the medium-intensity group and the low-intensity group increased significantly (P<0.05) . Compared with the control group, the ultrastructure of skeletal muscle of high intensity group showed mitochondrial focal accumulation, cristae membrane damage, vacuole-like changes; Z-line irregularity of muscle fibers, and deficiency of sarcomere. Conclusion: Vibration must be lead to the abnormal mitochondrial morphology and structure and the disorder of energy metabolism due to the expression imbalance of mitochondrial fusion and fission genes in skeletal muscles of rabbits, which may be an important target of vibration-induced skeletal muscle injury.

Advanced glycated albumin induces macrophage pyroptosis via upregulating nucleotide-binding oligomerization domain-like receptor protein 3 / 生理学报

The purpose of the present study was to investigate the effect of advanced glycated albumin (AGE-alb) on pyroptosis of macrophages and the underlying molecular mechanisms. RAW264.7 macrophages were treated with AGE-alb (1, 2, 4 and 6 g/L) and control albumin (C-alb, 4 g/L) for 24 h, or preincubated with MCC950 (1 μmol/L) for 1 h and then treated with AGE-alb (4 g/L) for 24 h. Cell viability and caspase-1 activity were measured by MTT and assay kits, respectively. Lactate dehydrogenase (LDH) activity and the levels of interleukin-1β (IL-1β) and IL-18 in media were detected. Cell death degree was evaluated by TUNEL and Hoechst 33342/PI staining. The protein levels of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), procaspase-1 and cleaved caspase-1 were assessed by Western blot. The results showed that AGE-alb treatment caused obvious decrease in cell viability and increases in LDH leakage and the percentages of TUNEL- or PI-positive cells in a concentration-dependent manner. Additionally, AGE-alb promoted IL-1β and IL-18 secretion, upregulated NLRP3 expression, and increased caspase-1 activity especially at the dose of 4 and 6 g/L. However, MCC950 (an NLRP3 inhibitor) pretreatment inhibited significantly the decrease in cell viability and the increases in LDH leakage and percentages of TUNEL- or PI-positive cells induced by AGE-alb. Furthermore, MCC950 attenuated obviously AGE-alb-induced IL-1β and IL-18 secretion and caspase-1 activation. These results indicate that AGE-alb may induce macrophage pyroptosis, and the mechanism is at least partially by activating NLRP3-caspase-1 pathway.

Mechanism of the influence of CCE3 on bone mineral element metabolism in ovariectomized rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the influence of CCE3 on bone mineral element metabolism and relative hormone in ovariectomized rats.</p><p><b>METHODS</b>24 female SD rats were divided randomly into 4 groups (n = 6): (1) Normal control; (2) sham ovariectomy; (3) ovariectomy(OVX); (4) OVX + CCE3.</p><p><b>RESULTS</b>(1) Ca, Mg, S, Co, Mn, Zn reduced obviously and P increased in the bone of the OVX rats. (2) E2, P, TSH, T4, CT, cortisol, GH reduced obviously and IL-6, FSH, LH increased obviously in serum of the OVX rats. (3) CCE3 corrected the changes of Ca, Mg, S, Co, Mn, Zn and P in bone as well as the changes of E2, P, TSH, T4, CT, cortisol, GH and IL-6, FSH, LH in serum of the OVX rats.</p><p><b>CONCLUSION</b>Changes of relative hormone and IL-6 induced by CCE3 are the important mechanism of the influence of CCE3 on bone mineral element metabolism in ovariectomized rats.</p>

Effects of behind legs vibrations on erectile function in male rabbits / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effects of behind legs vibrations on erectile function in male rabbits through the concentration of plasma reproductive hormone and the expression of nitric oxide synthase (eNOS), endothelin-1 (ET-1) mRNA in vibrated male rabbits.</p><p><b>METHODS</b>30 male adult rabbits were assigned randomly to A group (vibration power: 3.02 m/s(2)), B group (vibration power: 6.13 m/s(2)), C group (vibration power: 12.26 m/s(2)) and control group. The concentration of expression of eNOS, ET-1 mRNA were measured with RT-PCR after rated for 30 days.</p><p><b>RESULTS</b>(1) Compared with 0 days vibration, after exposure to vibration for 10, 20, 30 days, the A, B, C group concentration of plasma T, LH are much lower (P < 0.05), the concentration of plasma E2 is much higher. (2) Compared with control group after exposed for 30 days, the expression of ET-1 mRNA [B group:(17.39 +/- 4.59) x 104; C group: (36.21 +/- 13.13) x 104 ] were much higher and expression of eNOS mRNA [A group: (19.11 +/- 6.83) x 104; B group: (11.86 +/- 3.15) x 104; C group: (4.68 +/- 3.26) x 104] was much lower, there were significant differences (P < 0.01).</p><p><b>CONCLUSIONS</b>The vibration of behind legs in rabbits resulted the concentration of plasma T, LH are much lower, the concentration of plasma E2 is much higher, increased the expression of eNOS mRNA, decreased the expression of eNOS mRNA, then vary the erectile function.</p>

Effect of exercise on bone mineral element metabolism and relative hormones in ovariectomized rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effect of exercise on bone mineral element metabolism and relative hormones in ovariectomized rats.</p><p><b>METHODS</b>24 female SD rats were divided randomly into 4 groups: (1) normal control, (2) sham ovariectomy, (3) ovariectomy (OVX), (4) OVX + exercise.</p><p><b>RESULTS</b>(1) Ca, Mg, S,Co,Mn, Zn reduced obviously and P increases in bone of the OVX rats. (2) E2, P, TSH, T4, CT, Cortisol, GH reduced obviously and IL-6, FSH, LH increased obviously in serum of the OVX rats. (3) Exercised opposed the changes of Ca, Mg, S, Co, Mn, Zn and P in bone as well as the changes of E2, P, TSH, T4, CT, Cortisol, GH and IL-6, FSH, LH in serum of the OVX rats.</p><p><b>CONCLUSION</b>Exercise may correct the changes of bone mineral element and the relative hormones in ovariectomized rats.</p>