Regulating effects of whole-body vibration on protein expression of p-GSK3β in bone marrow cells of ovariectomized osteoporosis rats / 生理学报

The aim of this study was to investigate the effects of whole-body vibration on Wnt/β-catenin signaling pathway in bone marrow cells of ovariectomized osteoporosis rats. Thirty-six healthy 3-month old female Sprague Dawley (SD) rats were randomly divided into the following three groups by body weight: sham-operation (Sham), ovariectomized (OVX), and OVX whole-body vibration (WBV) groups. Ten weeks after ovariectomization, the rats of WBV group received vibration treatment (90 Hz, 15 min) twice per day. At the end of 8-week vibration, the whole-body bone mineral density (BMD) and body composition were detected by dual energy X-ray absorptiometry (DEXA) in vivo. The protein expressions of β-catenin and p-GSK3β in both bone marrow cells and bone marrow stromal cells were detected by Western blot. The results showed that, compared with OVX group, WBV group showed decreased fat mass and fat mass content, as well as increased lean body mass content. The BMD of the proximal tibia in WBV group was significantly higher than that in OVX group, however, there was no difference of BMD in whole-body and other positions between the two groups. The β-catenin expression in bone marrow stromal cells showed no difference between OVX and WBV groups. The p-GSK3β expression of bone marrow cells was increased in WBV group compared with that in OVX group, whereas bone marrow stromal cells from two groups did not exhibit the difference of the p-GSK3β expression. These results suggest that whole body vibration can stimulate the protein expression of p-GSK3β in bone marrow cells of ovariectomized osteoporosis rats, which could improve the bone loss induced by ovariectomization.

Changing trends of the expression of TIMP-4 in mouse ovary during pregnant and postpartum period / 中国应用生理学杂志

<p><b>AIM</b>The changes of tissue inhibitor of metalloproteinase-4 (TIMP-4) expression in mouse ovary during pregnant and postpartum period were studied to investigate the role of TIMP-4 in corpus luteum (CL).</p><p><b>METHODS</b>RT-PCR was used to deter mine the change of TIMP-4 mRNA and indirect immunofluorescence was used to observe the change of TIMP-4 protein. The expression of TIMP-4 mRNA was observed in various periods throughout the stage of pregnancy and postpartum day 1.</p><p><b>RESULTS</b>The expression of TIMP-4 was gradually enhanced from day 1 to day 8, reached a maximal expression at day 8, while decreased at day 11 and to the lowest level at postpartum day 1. Indirect immunofluorescence results further indicated that TIMP-4 protein was localized to CL and theca-intera cells in various periods throughout the pregnancy and postpartum day 1. In addition, the change pattern of TIMP-4 protein agreed with that of the TIMP-4 mRNA in pregnancy CL.</p><p><b>CONCLUSION</b>The expression of TIMP-4 in mouse ovary during pregnancy and postpartum is in spatio-temporal pattern and it may be involved in the formation and function maintain of CL during pregnancy in mice.</p>

The suppression of melatonin on mouse oocyte in vitro maturation of mouse / 中国应用生理学杂志

<p><b>AIM</b>To study whether melatonin has effect on oocyte maturation of mouse in vitro.</p><p><b>METHODS</b>Mouse oocytes were cultured in maturation medium, HX-medium, or HX-medium supplemented with FSH, and the effects of MT on meiotic maturation of mouse oocyte were examined.</p><p><b>RESULTS</b>(1) MT at all doses of 0.1 g/L, 0.02 g/L, 0.4 g/L or 0.8 g/L inhibited the formation of PB1 in CEO cultured in maturation medium and had no effect on GVBD. (2) MT could delay GVBD and the extrusion of PB1 in CEOs of mouse oocytes by dynamic curves. In contrast to the control, GVBD and PB1 extrusion of oocytes in the treated groups had been delayed by 8-10 hours and 3-4 hours respectively. (3) MT inhibited the effect of FSH on resumption of meiosis, but no effect on the formation of PB1. (4) MT and HX had cooperation effects on spontaneous oocyte maturation in CEO, but not in DO.</p><p><b>CONCLUSION</b>MT is able to affect mouse oocyte maturation and the regulation mechanisms may be related to cumulus cells.</p>