Screening of active components and preliminary mechanism exploration of Lycii Fructus for improving osteoporosis based on the zebrafish model / 药学学报

Juvenile zebrafish were used to screen the active components of Lycii Fructus for improving osteoporosis. The screening results were further verified by zebrafish adult osteoporosis model and the action mechanism was explored. Prednisolone was used as the inducer to build osteoporosis models of juvenile and adult zebrafish, and 9 groups of samples of different extracts and chemical parts of Lycii Fructus were given. Alizarin red staining was applied for observing the scale matrix mineralization and bone resorption. The activities of osteoblasts and osteoclasts were detected using alkaline phosphatase (ALP) and tartrate resistant acid phosphatase (TRAP/TRACP) staining. The expressions of bone metabolism-related genes alp, osteoprotectin (opn), osteoblast specific transcription factor (sp7), cathepsin K (ctsk), tracp, and Runt family transcription factor 2b (runx2b) in each group were determined using quantitative polymerase chain reaction. The results showed that all components of Lycii Fructus improved the formation area of the first vertebrae, the staining light density value, and the number of vertebrae joints in juvenile zebrafish and the Lycium barbarum polysaccharide (LBP) treatment group exerted the best effect. In addition, LBP prevented the formation of bone resorption lacunae in zebrafish scales, increased ALP activity, decreased TRAP activity, up-regulated the alp, sp7, and opn genes, and lowered the expressions of ctsk and tracp genes. In conclusion, LBP regulated the activity of osteoblasts and osteoclasts, reduced bone resorption, promoted bone formation and enhanced bone density, which might be the main anti-osteoporosis active fraction of Lycii Fructus. This study provided modern scientific evidence for the scientific connotation of the traditional effect of "strengthening bones and muscles" of Lycii Fructus, provided the reference for the evaluation of the anti-osteoporosis activity of traditional Chinese medicine based on zebrafish adult model, and provided beneficial enlightenment for the bone health needs of the aging society population.

Expression and regulation of pituitary adenylate cyclase-activating polypeptide mRNA in pregnant rat corpus luteum / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the expression changes and regulation of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in corpus luteum during pregnancy.</p><p><b>METHODS</b>Pregnant rats' ovaries were collected at different time points. The techniques of RT-PCR and in situ hybridization were used to observe expression changes of PACAP mRNA in rat ovaries during pregnancy. To further explore the regulation mechanism of PACAP mRNA expression in corpus luteum, luteal cells were cultured in vitro. Immature (25 - 28 days old) female Sprague-Dawley rats were injected subcutaneously with 50IU pregnant mare serum gonadotrophin (PMSG), and 25IU human chorionic gonadotrophin (hCG) 48 h later, to induce follicular development and luteum formation. On day 6 after hCG administration (the day of hCG administration was the first day), the rats were killed by guillotine and the ovarian luteal cells were collected. After incubation for 24 h, luteal cells were administration with various factors for 24 h. And then expression changes of PACAP mRNA in luteal cells after administration with different factors were detected by RT-PCR, and radioimmunoassay was used to analyze progesterone levels.</p><p><b>RESULTS</b>With the development of pregnancy, the expression of PACAP mRNA increased gradually, reached the peak at pregnancy 19 d, and then decreased. Compared with control group, platelet activating factor (PAF), forskolin and PMA could obviously stimulate PACAP mRNA expression in luteal cells which were cultured with corresponding factors for 24 h. At the same time, progesterone levels in culture media were also elevated.</p><p><b>CONCLUSION</b>PACAP, acting as a local ovary regulator, was closely related to the maintenance of medium-term and late pregnancy. PAF could directly stimulate PACAP mRNA expression in luteal cells, and protein kinase C (PKC) and protein kinase A (PKA) signal pathways could both participate in this process.</p>

Effect of zuoguiyin on the expression of ovarian follicle-stimulating hormone receptor in rats during peri-menopausal period / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effect and mechanism of Zuoguiyin (ZGY, a Chinese medical remedy for regulating qi and nourishing yin) on expression of ovarian follicle-stimulating hormone receptor (FSHR) in rats during peri-menopausal period (PMP).</p><p><b>METHODS</b>PMP rats were administered with low (13.78 g/kg), middle (20.67 g/kg) and high (31.00 g/kg) dose ZGY respectively by gastrogavage for eight weeks. FSHR mRNA and protein expressions were detected by RT-PCR and immunohistochemistry respectively. Besides, granulosa cells, collected from pregnant mare serum treated nonage rats, were incubated, and the level of FSHR mRNA expression in the cultured cells were detected after various disposals.</p><p><b>RESULTS</b>(1) Ovarian levels of FSHR mRNA and protein expressions in PMP rats were significantly lower than those in young rats (P<0.01), but were up-regulated significantly by ZGY treatment (P<0.01). (2) As compared with the control, FSHR mRNA expression increased in cultured granulosa cells after treated by ZGY extract; the increasing effect of ZGY was enhanced by combined treatment with Forskolin and attenuated by Genistein (a tyrosine protein kinase inhibitor).</p><p><b>CONCLUSION</b>ZGY could improve the ovarian functions during PMP by up-regulating the expression of FSHR and raise the ovarian responsibility to FSH, which may be possibly realized by activating cAMP-protein kinase and tyrosine protein kinase signal pathway.</p>

Risk factors of long-term cardiovascular diseases and cerebrovascular diseases in kidney allograft recipients / 中国医学科学院学报

<p><b>OBJECTIVE</b>To identify the risk factors of cardiovascular diseases and cerebrovascular diseases (CVD) events in kidney allograft recipients.</p><p><b>METHODS</b>We followed up 361 renal transplant recipients who had undergone renal transplantation in our center from January 2000 to December 2003 and evaluated the cumulative incidences and mortalities of CVD complications at baseline and post-transplantation 1, 3, 6, 12, 24, 36, 48, and 60 months. Kaplan-Meier plot was used to assess the incidence and Cox's proportional hazards model to determine the risk factors for cardiovascular complications.</p><p><b>RESULTS</b>The cumulative incidences of CVD were 3.1%, 5.4%, 9.9%, 13.0%, 18.0%, 21.1%, and 24.1%, 1, 6, 12, 36, 48, and 60 months after transplantation, respectively. History of diabetes mellitus (RR 2.19, 95% CI 1.32-3.97, P = 0.009) and CVD (RR 6.34, 95% CI 3.76-14.60, P = 0.002) as well as the post-transplantation hypertension (RR 1.18, 95% CI 1.02-1.34, P = 0.04), diabetes mellitus (RR 2.82, 95% CI 1.33-7.26, P = 0.002), hyperlipidemia (RR 2.04, 95% CI 1.26-5.17, P = 0.008) and abnormal creatinine (> 200 micromol/L, RR 1.81, 95% CI 1.08-3.21, P = 0.03), and proteinuria (> 0.3 g/d , RR 1.56, 95% CI 1.12-3.54, P = 0.05) were independently correlated with the development of cardiovascular events.</p><p><b>CONCLUSION</b>History of diabetes mellitus and CVD, post-transplant hypertension, diabetes mellitus, hyperlipidemia, abnormal creatinine and proteinuria are the independent risk factors of the development of CVD events.</p>

Pathogenesis of post-transplantation diabetes mellitus in 40 renal transplantation recipients / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore pathogenesis of post-transplantation diabetes mellitus (PTDM) in renal transplantation recipients.</p><p><b>METHODS</b>A total of 40 renal transplantation recipients were divided into three groups based on oral glucose tolerance test results: normal glucose tolerance (NGT) group (n = 10), impaired fasting glycaemia + impaired glucose tolerance (IFG + IGT) group (n = 16), and PTDM group (n = 14). Insulin resistance (IR) and beta cell function were assessed by homeostasis model.</p><p><b>RESULTS</b>The differences of the immunosuppressive agents used in these groups were not statistically significant (P > 0.05). Compared with NGT group, insulin area under curve and homeostasis model assessment-insulin resistance index were significantly higher in IGT + IFG group and PTDM group (P < 0.05). Compared with NGT group and IGT + IPG group, insulin secretion index at 30 min and homeostasis model assessment-insulin secretion index were significantly lower in PTDM group (P < 0.05).</p><p><b>CONCLUSION</b>Insulin resistance and beta-cell dysfunction may play a key role in the pathogenesis of PTDM.</p>

Role of platelet-activating factor in progesterone synthesis and vascular endothelial growth factor expression in rat luteal cells / 生理学报

The present study aimed to investigate the role of platelet-activating factor (PAF) in progesterone synthesis and vascular endothelial growth factor (VEGF) expression in rat luteal cells. Immature (25-28 days old) female Sprague-Dawley rats were injected subcutaneously with 50 IU pregnant mare serum gonadotrophin (PMSG), and 25 IU human chorionic gonadotrophin (hCG) 48 h later, to induce follicular development and luteum formation. On day 6 after hCG administration (the day of hCG administration was the first day), the rats were killed by guillotine and the ovarian luteal cells were collected. After incubation for 24 h, luteal cells were incubated without or with different doses (0.1 μg/mL, 1 μg/mL, 10 μg/mL) of PAF at 37 °C (5% CO(2)) for 24 h, and then progesterone concentration was evaluated by radioimmunoassay (RIA); apoptotic rate and VEGF mRNA expression in luteal cells were assessed by flow cytometry and RT-PCR, respectively. The results showed that PAF promoted progesterone production, with a maximal effect at 1 μg/mL (P<0.05); PAF increased apoptotic rate but not in a dose-dependent manner, and 10 μg/mL PAF enhanced apoptotic rate significantly (P<0.05); furthermore, PAF stimulated VEGF mRNA expression in luteal cells, especially at 1 μg/mL (P<0.01). It is suggested that PAF regulates progesterone synthesis and VEGF mRNA expression in luteal cells to mediate corpus luteum formation in rat ovary.

The changing trends of expression of VEGF and its relationship with the levels of NO in rat corpus luteum of pseudopregnant / 中国应用生理学杂志

<p><b>AIM</b>The expression of VEGF in rat ovaries corpus luteum and its expression pattern were observed to investigate the effect of VEGF on luteal formation and regression.</p><p><b>METHODS</b>The model of immature rat of pseudopregnant was established using pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG), the expression of VEGF in corpus luteum was detected by immunohistochemistry, the levels of VEGF in corpus luteum was measured by ELISA, and the levels of NO in corpus luteum was measured by chemistry assay.</p><p><b>RESULTS</b>VEGF expressed weakly in rat corpus luteum on the day 1, and enhanced gradually from day 3 to day 5, then went up to the peak on the day 7, and maintained to day 9. On the day 11, the expression of VEGF began to decrease. The levels of VEGF were similar to the expression of VEGF. The levels of NO appeared like double wave. The levels increased gradually from day 1 to day 5, and peaked on the day 7, then decreased on the day 9, while lightly increased on the day 11, and showed significant increase and reached the highest on the day 13, then decreased the lowest on the day 15.</p><p><b>CONCLUSION</b>There is a intimate temporal relationship between the expression of VEGF and angiogenesis in corpus luteum, VEGF may play a role in luteum formation by improving angiogenesis mediated by NO, NO may play a role in luteum regression as a luteolytic during the late luteal phase.</p>