Effectiveness of combined GnRH analogue plus raloxifene administration in the treatment of uterine leiomyomas: a prospective,randomized, single-blind,placebo-controlled clinical trial

BACKGROUND: Raloxifene hydrochloride is a synthetic non-steroidal drug used for the prevention and treatment of post-menopausal osteoporosis. Pre-clinical and clinical data have shown that raloxifene may have a beneficial effect on leiomyomas. The aim of this prospective single-blind, randomized, placebo-controlled clinical trial was to evaluate the effectiveness of the addition of raloxifene to GnRH analogues on uterine, leiomyoma, and non-leiomyoma sizes, and on the occurrence of leiomyoma-related symptoms. METHODS: After randomization using a computer-generated list, 100 pre-menopausal women with symptomatic uterine leiomyomas received either leuprolide acetate depot plus raloxifene 60 mg daily (group A) or leuprolide plus placebo tablet (group B) for six cycles of 28 days. At baseline and after treatment, uterine, leiomyoma and non-leiomyoma sizes, and leiomyoma-related symptoms were evaluated for each woman. Analysis was by intention-to-treat method. RESULTS: After six cycles of treatment, a significant decrease in uterine, leiomyoma, and non-leiomyoma sizes was detected in both groups in comparison with baseline. At the same time, no significant difference in uterine and non-leiomyoma sizes was observed between the groups. Leiomyoma sizes were significantly (P < 0.05) lower in group A than in group B. No difference was observed in leiomyoma-related symptoms between groups throughout the study period. CONCLUSIONS: In women treated with GnRH analogue, the raloxifene administration induces a higher reduction of leiomyoma sizes.     

盐酸雷洛昔芬的合成改进

目的:优化盐酸雷洛昔芬的合成路线.方法:以3-甲氧基苯硫酚和4-甲氧基-α-溴代苯乙酮为起始原料,经取代反应,环合反应得到6-甲氧基-2-(4-乙酰氧基苯基)苯并[b]噻吩,再与4-[2-(1-哌啶基)乙氧基]苯甲酰氯盐酸盐发生Friedel-Crafts反应,然后发生脱甲基反应,最后经成盐反应,共5步主要反应制得目标产物.结果:目标化合物结构经红外光谱、核磁共振氢谱及质谱确证.结论:本方法反应条件温和,操作简便,并且提高了产率.     

Who will benefit from treatment with selective estrogen receptor modulators (SERMs)?

Clinical trials have demonstrated that the selective estrogen receptor modulator raloxifene can reduce the risk of vertebral fracture, but have not unequivocally demonstrated an effect on non-vertebral fracture. Consequently it is recommended that raloxifene be used mainly in postmenopausal women with milder osteoporosis as a preventive measure or for treatment in those with predominantly spinal osteoporosis. Since the effects of raloxifene on bone mineral density and bone turnover may reverse soon after cessation, it is recommended that raloxifene be used as long-term therapy for 5-10 years. Because of its quicker offset, use of raloxifene may have advantages over potent bisphosphonates if use of anabolic agents are contemplated in an individual patient.     

Combination therapy with anabolic and antiresorptive agents

Combination therapy, the use of an anabolic agent with an antiresorptive agent in some sequence, has been evaluated in a number of clinical trials. There is no fracture data on combination therapy except for a small trial using PTH and estrogen. It appears that simultaneous use of a bisphosphonate (alendronate 10 mg per day) with PTH offers no advantage (and appears to blunt PTH's effect) compared with the use of PTH alone based on bone density gains. Previous therapy with alendronate also blunts gains in bone density with PTH therapy. Estrogen and raloxifene, whether given before or with PTH, do not blunt its anabolic effect. Sequential therapy with PTH followed by an antiresorptive agent (alendronate) offers the greatest gains in bone mass. It is possible that alendronate or other bisphosphonates given in a different dosing regimes may have different effects on PTH's anabolic effect. More trial data on combination therapy is needed.     

Concentration-dependent effects of a selective estrogen receptor modulator raloxifene on proliferation and apoptosis in human uterine leiomyoma cells cultured in vitro

BACKGROUND: This study was conducted to elucidate the effects of raloxifeneon proliferation and apoptosis in cultured human uterine leiomyomacells. METHODS: The monolayer cultures were treated with graded concentrations(10^–9, 10^–8 and 10^–7 M) of raloxifeneand 10^–7 M 17-estradiol (E₂). Cell viability, percentageof proliferating cell nuclear antigen (PCNA)-positive cells,percentage of terminal deoxynucleotidyl transferase-mediated2'-deoxyuridine 5'-triphosphate nick-end labelling (TUNEL)-positivecells and the expression of PCNA and Bcl-2 proteins were assessedby 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxylphenyl)-2-(4-sulphophenyl)-2H-tetrazolium assay, immunocytochemistry, TUNEL assay and western blotanalysis, respectively. RESULTS: Compared with untreated cultures, the number of viable culturedcells, percentage of PCNA-positive cells and PCNA protein expressionwere significantly decreased by treatment with 10^–9 Mraloxifene, but increased by treatment with either 10^–8 Mor 10^–7 M raloxifene. In contrast, the percentageof TUNEL-positive cells was significantly increased and Bcl-2protein expression was significantly decreased by treatmentwith 10^–9 M raloxifene, whereas they were not affectedby treatment with either 10^–8 or 10^–7 M raloxifene. CONCLUSIONS: In cultured leiomyoma cells, low concentration (10^–9 M)of raloxifene may inhibit the growth of leiomyoma cells, whereashigh concentrations (10^–8 M, 10^–7 M) ofraloxifene may promote their growth.     

The effect of raloxifene on markers of bone turnover in older women living in long-term care facilities

OBJECTIVES: To examine the effect of raloxifene on bone turnover in elderly women. DESIGN: Clinical intervention. SETTING: Long-term care facilities. PARTICIPANTS: Nineteen women completed the study, mean age 85 (range 76-99). INTERVENTION: Raloxifene 60 mg was given daily for 12 weeks. MEASUREMENTS: Markers of bone turnover were plasma C-telopeptides of type I collagen (CTx), urine cross-linked N-telopeptides of type I collagen (NTx) and serum tartrate-resistant acid phosphatase (TRAP 5b), plasma osteocalcin, and serum bone alkaline phosphatase. Other markers were serum 25-OH vitamin D, parathyroid hormone, ionized calcium, and phosphate. Markers were measured at baseline, after calcium and vitamin D had been taken for 6 weeks, after raloxifene had been taken for 12 weeks, and 6 weeks after raloxifene had been stopped. Paired sample t test was used to examine changes in markers at each time point. RESULTS: Plasma CTx decreased on average by 31%, urinary NTx by 35%, plasma osteocalcin by 25%, serum bone alkaline phosphatase by 15% (P<.01), and serum TRAP 5b by 10% (P<.05) on treatment. CONCLUSION: Raloxifene reduces bone turnover in elderly women living in long-term care facilities. The effect of raloxifene on bone turnover is comparable with that seen in younger postmenopausal women.     

Characterization of a membrane-associated estrogen receptor in a rat hypothalamic cell line (D12)

The ability of estrogens to produce rapid changes in cellular function has been firmly established. The question remains whether these changes are mediated by a modified form of the nuclear estrogen receptor (ER) that is associated with the plasma membrane (mER) or by a completely novel membrane receptor. Therefore, we characterized the biochemical properties of the nuclear and membrane-associated ERs expressed endogenously in a rat hypothalamic endothelial cell line (D12). Radioligand binding experiments using D12 membrane fractions showed that these cells exhibit properties consistent with a binding site specific for estrogens (mER). Equilibrium binding assays using [¹²⁵I]16-α-iodo-3,17-β-estradiol revealed saturable binding to mER, an affinity value similar to nuclear ER, with differing receptor expression levels. Competition assays revealed that 9 of 12 ER ligands tested had comparable affinities for mER and ER. For example, 17-α-estradiol and estrone had similar binding characteristics for both receptors while differences were noted for raloxifene, 17β-estradiol (E2), and genistein. Western blot and immunocytochemical analyses using antibodies specific for ERα confirmed that D12 cells expressed a membrane-associated protein with a molecular mass (67 kDa) similar to that of ERα that colocalized with caveolae-enriched membranes. A rapid increase in intracellar Ca²⁺ levels in the presence of E2 suggests that mER can mediate physiologic changes through calcium mobilization. These data support the expression of mER in these brain-derived endothelial cells that is similar to, but biochemically distinguishable from, nuclear ERα.     

雷洛昔芬对去卵巢大鼠骨组织雌激素受体亚型表达的影响

目的 探讨雌激素受体在骨质疏松中的作用及雷洛昔芬对其调整作用.方法 选择3月龄Sprague-Dawley雌性大鼠48只,随机分为假手术组、去卵巢组、雌激素组及雷洛昔芬组,每组12只,给药3个月后处死大鼠.分离获取股骨,应用RT-PCR技术检测骨细胞中ER mRNA表达水平.结果 雷洛昔芬使去卵巢大鼠骨密度增加,提高ERα mRNA,对ERβ mRNA的表达无明显的影响作用.结论 雷洛昔芬可能通过对ER基因表达的影响而起到治疗骨质疏松的作用.     

雷洛昔芬对去卵巢大鼠血脂的影响

目的探讨选择性雌激素受体调节剂雷洛昔芬对去卵巢大鼠血脂的影响。方法将40只3月龄雌性SD大鼠随机分为5组,去卵巢组、假手术组、雌激素组、小剂量雷洛昔芬组(小剂量组)和大剂量雷洛昔芬组(大剂量组),每组8只。治疗3个月后,测量各组治疗前后体重、血压和血脂的变化。结果去卵巢组TC和LDL-C显著高于其他4组(P<0.01),雌激素组与假手术组比较无统计学差异(P>0.05),与小剂量组比较,大剂量组能更进一步降低TC和LDL-C(P<0.05)。去卵巢组TG与假手术组比较稍有升高,但无统计学差异,雌激素组TG高于假手术组和大、小剂量组(P<0.05)。去卵巢组HDL-C明显低于其他4组(P<0.01),雌激素组HDL-C与假手术组比较无统计学差异(P>0.05),与小剂量组比较,大剂量组能更进一步升高HDL-C(P<0.05)。结论雷洛昔芬可改善去卵巢大鼠的脂代谢状况,有助于降低绝经后的心血管危险。