Integripetal rhodiola herb attenuates high altitude-induced pulmonary arterial remodeling and expression of vascular endothelial growth factor in rats / 生理学报

The aim of this study was to investigate the effect of integripetal rhodiola herb on pulmonary arterial remodeling and expression of vascular endothelial growth factor (VEGF) in high altitude pulmonary hypertension in rats. Fifty healthy male Wistar rats were divided into five groups randomly: Plain control group (LC group), 10-day plateau group (H(10) group), 30-day plateau group (H(30) group), 10-day rhodiola-treated plateau group (R(10) group), and 30-day rhodiola-treated plateau group (R(30) group). Each group included 10 rats. The rats in LC group were kept in Chengdu (500 meters above sea level), and rats in H and R groups were kept in Lhasa (3 700 meters above sea level). The rats in R group were daily treated with integripetal rhodiola herb extract (24%, 10 mL/kg) intragastrically for 10 d or 30 d, while rats in LC and H groups were treated with the same volume of saline. Mean pulmonary arterial pressure (mPAP) was detected via a catheter in the pulmonary artery by pressure waveform monitoring. The ratio value of right ventricle weight to left ventricle plus septum weight [RV/(LV + S)] was measured. The microstructure of pulmonary arterioles was examined by electron microscopy. The expression of VEGF in the lung was investigated using immunohistochemistry. The results showed that mPAP and [RV/(LV + S)] in H(10) group and H(30) group were higher than those in LC group (P < 0.05); but there was no significant difference between H(10) group and R(10) group (P < 0.05); and mPAP and [RV/(LV + S)] in H(30) group were lower than those in H(30) group (P < 0.05). Electron microscopy showed that compared to LC group, arteriolar endothelial cells were arranged in a columnar or palisading form, protruding into the lumen, accompanied with luminal stenosis, irregular internal elastic membrane, and proliferation of vascular smooth muscle cells in H groups, which was more obvious in H(30) group than in H(10) group; while these pathological changes were attenuated in the R groups compared to H groups. The levels of VEGF protein in H groups were also higher than those in LC group (P < 0.05); while the expression of VEGF in R(30) group was lower than that in H(30) group. In summary, the results show that the integripetal rhodiola herb can attenuate high altitude-induced pulmonary arterial remodeling in rats, and the inhibition of VEGF protein expression by rhodiola may be one of the mechanisms.

The progesterone-induced expression of cyclin G1 and its effect on the proliferation of mouse uterine epithelial cells / 生理学报

The aim of the present study is to investigate the effect of progesterone-induced expression of cyclin G1 on the proliferation of endometrial epithelial cells. To obtain mouse endometrial epithelial cells, the uteri were isolated from ovariectomized mice which were injected subcutaneously with 100 ng estradiol per day for two days. Then the uteri were digested by dispase and pancreatin respectively. Endometrial epithelial cells were cultured in DMEM/F12 containing 6% fetal bovine serum, and divided into four groups when they grew to confluence. Each of the groups was treated as follows: Group E was treated with 0.01 micromol/L estradiol only, group P was treated with 1 micromol/L progesterone, group EP was treated with both 0.01 micromol/L estradiol and 1 micromol/L progesterone, and group C was treated with 0.01% DMSO for control. Immunocytochemistry was used to examine the expression of cyclin G1 protein. MTT assay was used to evaluate metabolic activity of cells. Flow cytometry was used to check the number of cells distributing in each phase of the cell cycle. The result of immunocytochemistry showed that there was no expression of cyclin G1 protein in group C and group E, while cyclin G1 was obviously expressed in group P and group EP and localized in nucleus. In the MTT assay, compared with group C, the viability of group E significantly increased, while that of both group P and group EP decreased significantly. The results of flow cytometry were in accordance with those of MTT, which showed that compared with group C, group E had a higher proportion of cells in S phase, while group P, as well as group EP had a lower proportion of cells in S phase but a higher proportion in G1 phase and G2/M phase. These results indicate that progesterone could induce cyclin G1 expression in the primary culture of mouse endometrial epithelial cells, meanwhile inhibit the proliferation of cells and block the cell cycle progression. Thus, progesterone-induced expression of cyclin G1 is probably a negative factor in regulating cell cycle, which is involved in the inhibitory effect of progesterone on the proliferation of endometrial epithelial cells.