雷洛昔芬对血管内皮细胞雌激素应答元件转录活性的影响

目的:研究选择性雌激素受体调节剂(SERM)雷洛昔芬(raloxifene)对血管内皮细胞雌激素应答元件(ERE)转录活性的影响。方法:首先构建ERE荧光素酶报告基因质粒(ERE-TK-Luc),然后采用真核细胞转染技术将ERE-TK-Luc与内参照质粒PRL-SV40一起转染体外培养的血管内皮细胞,检测raloxifene刺激的转染细胞荧光素酶的相对活性,与未用药的转染细胞进行比较。并同时采用raloxifene与雌二醇(E₂)共同处理细胞,观察raloxifene对E₂作用的影响。结果:在raloxifene处理的转染细胞中荧光素酶表达量低于未用药的转染细胞,raloxifene浓度为10^-7mol/L时更明显(P<0.01);E₂可使转染细胞荧光素酶表达量明显高于未给药组(P<0.01),而raloxifene与E₂同时处理则细胞荧光素酶表达水平与对照组相近(P<0.01)。结论:Raloxifene对血管内皮细胞ERE转录活性有抑制作用。     

p38MAPK在17β-雌二醇和雷洛昔芬促成骨细胞増殖和分化中的作用

目的:观察p38MAPK信号转导通路在17β-雌二醇和雷洛昔芬促成骨细胞增殖和分化过程中的作用。方法:取第一继代BALB/c小鼠头盖骨成骨细胞,药物刺激组分别加入不同浓度17β-雌二醇或雷洛昔芬;含阻断剂组预先添加不同浓度的SB202190(p38MAPK的阻断剂)阻断信号转导通路,再加17β-雌二醇或雷洛昔芬,作用72h后用MTT法与PNPP法测定细胞的增殖能力和碱性磷酸酶活性。结果:加入雌激素或雷洛昔芬后,成骨细胞的增殖和分化明显增强,与空白对照组比较差异具有显著性意义(P<0·05);阻断p38MAPK信号转导通路后,细胞增殖分化受到明显抑制,与未阻断组比较差异具有非常显著性意义(P<0.01)。结论:p38MAPK在17β-雌二醇和雷洛昔芬诱导的小鼠成骨细胞的増殖和分化过程中发挥重要作用。     

Effect of raloxifene on the incidence of elevated low density lipoprotein (LDL) and achievement of LDL target goals in postmenopausal women

SUMMARY

Objective: To determine the extent to which raloxifene can maintain low density lipoprotein cholesterol (LDL-C) levels below 160?mg/dL or reduce elevated LDL-C levels to below lipidlowering goals in postmenopausal women.

Patients and methods: The Multiple Outcomes of Raloxifene Evaluation (MORE) osteoporosis treatment trial randomized 7705 postmenopausal women to placebo or raloxifene (60?mg or 120 mg) daily for a core treatment phase of 3 years. Changes in LDL-C and other serum lipids in a subset of women was a predefined secondary objective. This post-hoc analysis included the 2413 women who did not take lipid-lowering medications at any time during the trial and for whom LDL-C measurements were available. The threshold for high LDL-C (≥ 160?mg/dL) and LDL-C lipid-lowering goals were defined according to National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) guidelines.

Results: The percent of women with LDL-C < 160?mg/dL was comparable between treatment groups at baseline (placebo, 57.5%; raloxifene 60?mg, 56.4%; raloxifene 120?mg, 56.8%). At 3 years, the percent of these women whose LDL-C had increased to above 160?mg/dL was significantly less in the raloxifene 60?mg and 120?mg groups compared with placebo by 65% (95% CI, 44%–78%) and 64% (95% CI, 43%–77%), respectively. Among women with elevated (defined for these analyses as ≥ 160?mg/dL) LDL-C at baseline, the proportion having elevated LDL-C at 3 years was significantly less in the raloxifene 60?mg and 120?mg groups compared with placebo by 32% (95% CI, 24%–40%) and 40% (95% CI, 32%–48%), respectively. Fifty percent and 13% of these women achieved LDL-C goals of <160?mg/dL and <130?mg/dL, respectively (P <0.001 vs. placebo for both) in the raloxifene 60?mg group, with similar results for the raloxifene 120?mg group.

Conclusions: In postmenopausal women with osteoporosis not taking concurrent lipid-lowering therapy, raloxifene significantly reduced the incidence of LDL-C ≥ 160?mg/dL and significantly increased the proportion achieving LDL-C goals for lipid-lowering compared with placebo. Whether these and other effects of raloxifene on cardiovascular risk markers will improve cardiovascular outcomes requires further study.     

雷洛昔酚对大鼠垂体的作用

目的 观察雷洛昔酚是否能诱发出催乳素瘤的动物模型以及对PRL水平的影响,以研究雷洛昔酚对大鼠垂体的作用。方法雌性Wistar大鼠切除卵巢后,分别在皮下埋植含有雷洛昔酚、雌激素和空白硅胶管,术后8周处死大鼠,检测大鼠体重变化、垂体重量变化、血清催乳素(PRL)水平和垂体组织学变化。结果雷洛昔酚组与阴性对照组大鼠体重无明显统计学差异,与雌激素组大鼠体重具有统计学差异(P<0.05)；雷洛昔酚组与阴性对照组大鼠垂体重相比无明显差异,与雌激素组大鼠垂体重相比具有统计学差异(P<0.05)；雌激素组大鼠血清PRL水平最高,阴性对照组血清PRL水平最低,雷洛昔酚组介于两者之间,分别与雌激素组、对照组相比较差异均具有统计学意义(P<0.05)；雷洛昔酚组与对照组垂体病理为正常细胞形态,雌激素组垂体病理为PRL瘤表现。结论雷洛昔酚对大鼠垂体有一定的影响,但不能诱发催乳素瘤。     

盐酸雷洛昔芬自微乳化给药系统处方的初步研究

目的研究盐酸雷洛昔芬(Raloxifene hydrochloride)自微乳制剂的处方。方法通过考察盐酸雷洛昔芬在各种辅料中的溶解度,对各种辅料的自乳化性能进行筛选;采用正交设计试验优化处方,分别以透光率、乳化速度、有无油层、药物溶解难易程度及三相混合是否分层为评价指标,确定最佳的油相,乳化剂,助乳化剂组合。结果盐酸雷洛昔芬在乙酸乙酯、辛酸/癸酸三甘油酯(GTCC)、丙二醇单辛酸酯(CAPRYOL90)中的溶解度为:13.82±0.94μg·m L-1、43.25±3.76μg·m L-1、157.1±2.28μg·m L-1;在乳化剂吐温-85、聚氧乙烯氢化蓖麻油RH(Cremophor-RH)、吐温-80中的溶解度为627.2±24.3μg·m L-1、693.3±20.6μg·m L-1、878.7±8.56μg·m L-1;在助乳化剂聚乙二醇-400(PEG-400)、1,2-丙二醇、二乙二醇单乙醚(Transcutol P)中的溶解度分别为965.4±0.37μg·m L-1、858.0±0.91μg·m L-1、2869.0±0.37μg·m L-1。盐酸雷洛昔芬自微乳剂组成:盐酸雷诺昔芬、乙酸乙酯、Cremophor-RH40、Transcutol P,优化的处方为盐酸雷洛昔芬5mg,乙酸乙酯0.15g,Cremophor-RH40 0.15g,Transcutol P 0.15g,平均粒径为8.99nm,分散系数为0.377。结论盐酸雷洛昔芬自微乳制备简单,性质稳定,质量易控,有良好的自乳化能力。     

Improvement in spine bone density and reduction in risk of vertebral fractures during treatment with antiresorptive drugs

PURPOSE: To estimate how much the improvement in bone mass accounts for the reduction in risk of vertebral fracture that has been observed in randomized trials of antiresorptive treatments for osteoporosis. METHODS: After a systematic search, we conducted a meta-analysis of 12 trials to describe the relation between improvement in spine bone mineral density and reduction in risk of vertebral fracture in postmenopausal women. We also used logistic models to estimate the proportion of the reduction in risk of vertebral fracture observed with alendronate in the Fracture Intervention Trial that was due to improvement in bone mineral density. RESULTS: Across the 12 trials, a 1% improvement in spine bone mineral density was associated with a 0.03 decrease (95% confidence interval [CI]: 0.02 to 0.05) in the relative risk (RR) of vertebral fracture. The reductions in risk were greater than predicted from improvement in bone mineral density; for example, the model estimated that treatments predicted to reduce fracture risk by 20% (RR = 0.80), based on improvement in bone mineral density, actually reduce the risk of fracture by about 45% (RR = 0.55). In the Fracture Intervention Trial, improvement in spine bone mineral density explained 16% (95% CI: 11% to 27%) of the reduction in the risk of vertebral fracture with alendronate. CONCLUSION: Improvement in spine bone mineral density during treatment with antiresorptive drugs accounts for a predictable but small part of the observed reduction in the risk of vertebral fracture.     

Results from a randomized trial of a web-based,tailored decision aid for women at high risk for breast cancer

Objective

To assess the impact of Guide to Decide (GtD), a web-based, personally-tailored decision aid designed to inform women's decisions about prophylactic tamoxifen and raloxifene use.

Methods

Postmenopausal women, age 46–74, with BCRAT 5-year risk ≥1.66% and no prior history of breast cancer were randomized to one of three study arms:intervention (n = 690), Time 1 control (n = 160), or 3-month control (n = 162). Intervention participants viewed GtD prior to completing a post-test and 3 month follow-up assessment. Controls did not. We assessed the impact of GtD on women's decisional conflict levels and treatment decision behavior at post-test and at 3 months, respectively.

Results

Intervention participants had significantly lower decisional conflict levels at post-test (p < 0.001) and significantly higher odds of making a decision about whether or not to take prophylactic tamoxifen or raloxifene at 3-month follow-up (p < 0.001) compared to control participants.

Conclusion

GtD lowered decisional conflict and helped women at high risk of breast cancer decide whether to take prophylactic tamoxifen or raloxifene to reduce their cancer risk.

Practice implications

Web-based, tailored decision aids should be used more routinely to facilitate informed medical decisions, reduce patients’ decisional conflict, and empower patients to choose the treatment strategy that best reflects their own values.     

A Nationwide Study on the Incidence of Breast Cancer in Korean Women with Osteoporosis Receiving Raloxifene Treatment

PurposeRaloxifene is a selective estrogen receptor modulator (SERM), and raloxifene treatment for osteoporosis is reimbursable under the Korean National Health Insurance. Evidence suggests that SERMs use reduces the risk of breast cancer in Asian population. Herein, we retrospectively investigated the protective effect of raloxifene on breast cancer rates in Korean population.MethodsUsing the Health Insurance Review and Assessment Service database, we selected women with osteoporosis aged 50 years and above. Patients treated for at least 2 years with raloxifene were assigned to the user group, whereas the remaining patients were assigned to the non-user group. The effect on breast cancer risk was assessed using the Cox proportional-hazards model with a time-dependent covariate to adjust for immortal time bias.ResultsA total of 322,870 women who were registered between 2010 and 2011 were included. The user group comprised 0.7% (n = 2,307) of the total population. The mean age was 65.7 ± 8.0 years and 67.2 ± 8.6 years in the user and non-user groups, respectively (p < 0.001). There was no difference in the previous use of estrogen replacement between the 2 groups (p = 0.087). The incidence of breast cancer per 1,000 person-years was 0.49 (n = 8) and 0.68 (n = 1,714) in the user and non-user groups, respectively (hazard ratio [HR], 0.63, 95% confidence interval [CI], 0.32–1.27). HR decreased with increase in the treatment duration, but this change was not statistically significant (HR, 1.00, 95% CI, 0.32–3.11 in 2–3 years; HR, 0.63, 95% CI, 0.20–1.94 in 3–4 years; and HR, 0.41, 95% CI, 0.10–1.65 in 4–5 years).ConclusionLong-term treatment with raloxifene in women with osteoporosis was not significantly associated with a reduction in breast cancer rates. However, further investigation is required for a conclusive proof.     

雷洛昔芬治疗绝经后妇女骨质疏松症的系统评价

目的 评价雷洛昔芬治疗绝经后骨质疏松症的疗效和安全性.方法 计算机检索MEDLINE、EMBASE、Cochrane图书馆临床对照试验注册中心、中国生物医学文献数据库、中国期刊全文数据库、数字化期刊全文数据库,并手工检索相关领域其他杂志.检索不受语种限制,时间截止至2012年11月.以患绝经后骨质疏松症的女性为研究对象、比较雷洛昔芬与安慰剂的随机对照试验,评价纳入研究的质量,用RevMan5.1软件进行Meta分析,并采用GRADE系统评价证据质量评价.结果 纳入11个随机对照试验,包括21028例患者.患者腰椎BMD升高达2.39%,且60 mg/d剂量提高腰椎BMD强于30 mg/d组,但60 mg/d与120 mg/d以上剂量组间效果无差别,能有效降低椎体骨折发生率,降低幅度达40%.基于上述系统评价结果,采用GRADE系统评价证据质量及推荐等级,证据总体质量评级为低质量,推荐强度为弱推荐.结论 雷洛昔芬治疗绝经后骨质疏松症疗效肯定,能提高腰椎骨密度,降低椎体骨折的风险,但尚无证据支持其能降低非椎体骨折发生率.     

Raloxifene blocks estradiol induction of the serotonin transporter and 5-hydroxytryptamine2A receptor in female rat brain

Sex steroids have potent effects on mood, mental state and cognition. Our previous findings and those of others suggest that these effects may be due at least in part to estradiol actions on central serotonergic mechanisms. Specifically, estradiol-17beta in its acute positive feedback mode for gonadotropin release in the female rat induces expression of the genes for the 5-hydroxytryptamine(2A) receptor (5-HT(2A)R) and the serotonin transporter (SERT) in the dorsal raphe nucleus (DRN). This is accompanied by an increase in the densities of 5-HT(2A)R and the SERT in forebrain regions which in the human are concerned with the control of mood, mental state, cognition and emotion. Here we report that raloxifene, a benzothiophene and selective estrogen receptor modulator (SERM), completely blocked estradiol stimulation of brain 5-HT(2A)R and SERT expression in acutely ovariectomized rats. Raloxifene also blocked the estrogen-induced surge of luteinizing hormone. Treatment of acutely ovariectomized rats with raloxifene alone increased the density of SERT sites in the mid-frontal cortex and decreased the density of 5-HT(2A)R in the posterior olfactory tubercle. The inhibitory effects of raloxifene on acute estrogen-induction of central serotonergic mechanisms were similar to those of tamoxifen even though there are major differences between the two SERMs in their affinity for the two estrogen receptor subtypes and their actions on the uterus. These findings provide robust evidence that estradiol induction of the 5-HT(2A)R and the SERT in brain is mediated by nuclear estrogen receptors. Our data may provide the basis for obtaining a better understanding of the effects of sex steroids on mood and mental state in the human and the possible rational development of congeners of sex steroids for the treatment of mental disorders.