Sleep-disordered breathing is associated with depletion of circulating endothelial progenitor cells and elevation in pulmonary arterial pressure in patients with decompensated systolic heart failure

Background Sleep-disordered breathing (SDB) is known to occur frequently in and may predict worsening progression of patients with congestive heart failure (CHF). SDB is also known to play an important role in the development of idiopathic pulmonary arterial hyperten?sion (PAH) via inducing endothelial dysfunction and vascular remodeling, a pathological process that can be significantly influenced by factors such as osteoprotegerin (OPG) and endothelial progenitor cells (EPCs). The objective of this study is to determine if CHF with SDB is associated with changes in OPG, EPCs, and PAH. Methods EPCs were isolated, cultured, and quantified from CHF patients with SDB (n = 52), or without SDB (n = 68). OPG and N-terminal pro-brain natriuretic peptide (NT-proBNP) from each group was analyzed and correlated with EPCs and the mean pulmonary artery pressure (mPAP) measured by right heart catheterization. Results A significant decrease in circulating EPCs (29.30 ± 9.01 vs. 45.17 ± 10.51 EPCs/× 200 field; P < 0.05) was found in CHF patients with SDB compared to those without SDB. Both OPG (789.83 ± 89.38 vs. 551.29 ± 42.12 pg/mL; P < 0.05) and NT-proBNP (5946.50 ± 1434.50 vs. 3028.60 ± 811.90 ng/mL; P < 0.05) were also significantly elevated in SDB CHF patients who also had significantly elevated mPAP (50.2 ± 9.5 vs. 36.4 ± 4.1 mm Hg; P < 0.05). EPC numbers correlated inversely with the episodes of apnea and hypopnea per hour (RDI, r = –0.45, P = 0.037) and blood level of OPG (r = –0.53, P = 0.011). Although NT-proBNP was also increased significantly in patients with SDB, it had no correlation with either EPCs or RDI. Conclusions SDB due to hypoxemia from decompensated CHF is associated with (1) OPG elevation, (2) EPC depletion, and (3) mPAP elevation. The inverse relationship of circulating OPG with EPCs suggests a likely mechanism for hypoxemia and OPG in the development of pulmonary vascular dysfunction via depleting EPCs, thus worsening prognosis of CHF.     

失神经支配在大鼠骨折愈合过程中降钙素基因相关肽对骨保护素/破骨细胞分化因子影响的实验研究

目的 通过建立选择性切断大鼠感觉/运动神经联合胫骨骨折的动物模型,研究感觉/运动神经损伤后对骨折愈合的影响,并检测骨折愈合过程中降钙素基因相关肽(calcitonin gene related peptide,CGRP)对骨保护素(osteoprotegerin,OPG)/破骨细胞分化因子(receptor activator nuclear factor kappa B ligand,RANKL)体系的影响,初步探讨周围神经调节骨折愈合的机制.方法 取60只Wistar大鼠随机分为3组:前根(运动神经)切断+胫骨骨折组(anterior rhizotomy group,ART组);后根(感觉神经)切断+胫骨骨折组(posterior rhizotomy group,PRT组);单纯胫骨骨折组(sham operated group,SO组).分别于骨折术后7、14、21、28d处死大鼠,在骨折处上、下5mm部位取骨痂标本.免疫组织化学检测CGRP、OPG、RANKL的表达;采用软件Image-proplus 6.0进行图片分析;采用SPSS16.0进行统计学分析.结果 CGRP在SO组各时间点均呈强阳性表达,术后14 d和21 d,SO组、ART组和PRT组比较差异均有统计学意义(P＜0.05).OPG在SO组术后7d呈强阳性表达,以后逐渐下降但保持较高水平;术后14 d,PRT组和SO组、ART组比较差异有统计学意义(P＜0.05);术后21 d,SO组和PRT组、ART组比较差异有统计学意义(P＜0.05).RANKL在SO组21 d为表达高峰,以后逐渐下降;术后14 d,PRT组和ART组、SO组比较差异有统计学意义(P＜0.05);术后21 d,SO组和ART组、PRT组比较差异有统计学意义(P＜0.05).结论 在骨折愈合过程中,感觉神经纤维对骨折愈合的影响较运动神经纤维显著.CGRP能够调节OPG/RANKL的表达量的比值,从而影响骨折的愈合过程.失神经支配(尤其是感觉神经)导致CGRP对OPG/RANKL表达的调节作用降低,这不利于骨折的愈合.完整的神经支配是正常骨折愈合的必要条件之一.     

单侧髋关节置换术患者手术前后外周血中OPG与RANKL浓度对比分析

[目的]探讨老年患者（≥65岁）单侧髋关节术后短期内骨代谢变化.[方法]收集单侧髋关节置换手术患者术前后18例外周血液,采用ELISA法检测血清中骨保护素（OPG）、核激活因子受体配体（RANKL）手术前后浓度,分析OPG、RANKL表达水平变化.[结果]单侧18例行髋关节置换术患者术后OPG浓度均较术前明显增加,而16例患者术后RANKL浓度均明显下降,其中2例患者术后RANKL浓度轻度增加,术后患者RANKL/OPG比值总体下降.[结论]老年患者单侧髋关节术后OPG浓度增加和RANKL浓度的下降,导致RANKL/OPG比值总体下降,提示此类患者其术后短期内破骨功能可能受抑制而成骨功能却明显增强.     

不同龄小鼠成骨细胞OPG和RANKL表达的变化

目的观察来源于不同龄小鼠成骨细胞经雌激素作用后,分泌骨保护素(osteoprotegerin,OPG)、核因子κB受体(receptor activator of nuclear factor-κB ligand,RANKL)的变化.方法经雌激素作用前后,反转录-聚合酶链反应(RT-PCR)以及酶联免疫吸附试验(ELISA)测定OPG、RANKL表达的变化.结果经雌激素作用后,幼年组和成年组OPG分泌显著增多,而老年组RANKL表达明显下调.结论雌激素可以刺激成骨细胞分泌OPG,减少RANKL表达,很可能是骨质疏松的发生机制之一,是绝经后骨质疏松发生的重要原因.     

Increased serum osteoprotegerin level in older and diabetic hemodialysis patients

Osteoprotegerin is a circulating osteoclastogenesis inhibitory factor and serum osteoprotegerin levels are elevated in hemodialysis patients. This study investigated whether osteoprotegerin levels correlated with various clinical parameters in hemodialysis patients. The subjects were 45 men and 37 women aged from 27 to 94 years (mean = 60.4 +/- 13.9 years), and the duration of dialysis was 9-277 months (mean = 89.5 +/- 64.7 months). Serum osteoprotegerin levels were measured by enzyme-linked immunosorbent assay. Data were analyzed by stepwise multiple regression analysis. The mean osteoprotegerin level of the hemodialysis patients was 303 +/- 210 pg/mL, which was higher than in age-matched healthy controls. Osteoprotegerin levels increased with age, a longer duration of dialysis, and the presence of diabetes. Skeletal resistance to parathyroid hormone might be increased by aging, a long dialysis period, and diabetes, perhaps explaining why adynamic bone disease is more common in older or diabetic patients.     

护骨素基因启动子区T950-C多态性与骨密度及骨代谢的关系

目的探讨绝经后汉族妇女护骨素(OPG)基因启动子区T^950-C多态性与骨质疏松症和骨代谢的关系。方法应用PCR—RFLP测定随机选取的73例绝经后骨质疏松症妇女和61例绝经后正常妇女OPG基因T^950-C的基因型，双能X线骨吸收方法分别测腰椎各椎体和股骨颈髋部的BMD，放射免疫分析法测骨代谢指标。结果所选人群OPG基因T^950-C基因型频率分布在骨质疏松症和绝经正常妇女均符合Hardy-Weinberg定律，而且其基因型在两组研究对象中分布差异无显著性，但汉族妇女T^950-C基因型分布与高加索人种妇女相比有明显差异。在骨质疏松症组CC型的股骨颈BMD低于TT型和TC型，而绝经后正常妇女三种基因型之间BMD无差异。结论OPG基因T^950-C基因型分布存在明显的种族差异。OPG基因T^950-C多态性不能作为中国汉族妇女是否发生骨质疏松症的遗传标志，但对于患有骨质疏松症的中国汉族妇女CC型却能预测骨骨质疏松症的患病程度。     

血浆护骨素水平与内皮祖细胞在老年2型糖尿病患者血管病变中的关系探讨

目的 探讨老年2型糖尿病（T2DM）患者血浆护骨素（OPG）水平与外周血内皮祖细胞（endothelial progenitor cells,EPCs）含量的相关性,并分析在老年T2DM血管病变中的作用.方法 （1）采用流式细胞仪测定20例初诊T2DM患者、20例血糖控制良好（HbA1c ＜7％） T2DM患者（A组）、20例血糖控制中等（HbA1c7％～11％） T2DM患者（B组）、20例血糖控制较差（HbA1c＞1 1％） T2DM患者（C组）及10例糖耐量正常的健康对照者外周血中EPCs的含量; （2）采用酶联免疫分析法检测上述患者的血浆OPG水平.结果 （1）EPCs在T2DM组低于健康对照组,OPG在T2DM组高于健康对照组,且均有统计学差异（P＜0.05）; （2）C组血浆EPCs的水平低于B组及A组,B组低于A组,且有统计学差异（P＜0.05）;C组血浆OPG的水平高于B组及A组（P＜0.01）,B组血浆OPG的水平高于A组,差异有统计学意义（P＜0.05）; （3）单因素分析结果显示,糖尿病患者外周血中OPG水平与EPCs含量呈负相关（r=-0.354,P＜0.05）;多元回归分析结果显示,FPG、OPG、EPCs为血管病变的影响因素（P＜0.05）.结论 老年T2DM患者中空腹血清OPG水平与EPCs存在一定关系,二者可能在老年T2DM血管病变发生发展中发挥一定作用.     

Rheumatoid arthritis: new insights into the role of synovial inflammation in joint destruction

Abstract

Rheumatoid arthritis (RA) is characterized by inflammation and proliferation of synovial tissue, leading to degradation of articular cartilage and bone with functional impairment as a result. It has recently become clear that early suppression of synovial inflammation is essential in preventing progressive joint destruction, although inflammation and destruction are in part uncoupled. New insights into the role of matrix metalloproteinases (MMPs), aggrecanase, granzyme B, receptor activator of nuclear factor κB (RANK)–receptor activator of nuclear factor κB ligand (RANKL) interaction, and other factors involved in joint destruction may lead to the development of novel therapies aimed at specific inhibition of cartilage and bone degradation.     

Changes in the serum sex steroids, IL-7 and RANKL-OPG system after bone marrow transplantation: influences on bone and mineral metabolism

This study prospectively investigated the changes of the serum levels of the sex steroids, IL-7, soluble receptor activator of nuclear factor κB ligand (sRANKL) and osteoprotegerin (OPG) in bone marrow transplantation (BMT) recipients. This study also examined whether the changes of these cytokine levels and sex steroids actually influence bone turnover and post-BMT bone loss by correlation analysis. Data were analyzed from 39 patients (33.6 ± 6.4 years, 19 men and 20 women) who had DXA performed before BMT and at 1 year after BMT. The bone turnover markers, sex steroids and the cytokine levels were measured before BMT and serially after BMT.

The mean bone loss in the lumbar spine and the total proximal femur was 5.9% (P < 0.01) and 11.3% (P < 0.01), respectively. During the immediate post-BMT period, bone formation decreased, whereas the bone resorption increased. For the female recipients, the estradiol levels declined at 1 week after BMT, and they did not recover to the basal levels. For the male recipients, the testosterone levels decreased at 1 week and then it increased to its baseline level. The IL-7 levels reached their maximum at 1 week and then declined to baseline level by 3 months. The serum sRANKL, OPG levels and the sRANKL/OPG ratio showed their peak at post-BMT 3 weeks.

The mean daily dose of steroid was associated with suppressed bone formation, enhanced bone resorption and increased sRANKL levels. The IL-7 levels were also noted to be either positively correlated with the levels of ICTP or they were negatively correlated with the levels of osteocalcin at 1 and 3 weeks after BMT. Bone loss at the lumbar spine and the proximal femur was influenced by the decreased sex steroids and increased IL-7 levels. During the observation period, the IL-7 levels showed positive correlations with the sRANKL levels and the sRANKL/OPG ratio. For the female patients, the serum IL-7 levels were negatively associated with the estradiol levels at 1 and 3 weeks after BMT.

All these findings suggest that IL-7 plays an important role for post-BMT bone loss, and this possibly happens via the RANKL pathway. These data also suggest that the up-regulation of IL-7 during the early post-BMT period may result from a deficiency of estrogen.     

淫羊藿苷对人成骨细胞增殖及OPG蛋白表达的实验研究

目的：建立体外培养人成骨细胞系,观察淫羊藿苷对人成骨细胞增殖的影响,以及对人成骨细胞内骨保护素（Osteoprorotegerin,OPG）蛋白表达的影响,探讨淫羊藿苷促进人成骨细胞骨形成的可能作用机制。方法：将手术中取得的人股骨头松质骨骨片,使用酶消化法进行培养,取生长良好的第3代人成骨细胞进行实验。实验分为4组,对照组给予15%NCS-DMEM-F12（1：1）培养液培养;淫羊藿苷组分别于正常培养液内添加终浓度为10-6、10-8、10-10mol/L淫羊藿苷。噻唑蓝比色法（MTT）分别在培养1、3、5、7、9d后观察各组人成骨细胞的增殖情况,用蛋白免疫印迹方法（in-cell western blot）测定各组培养8、10、12d后人成骨细胞内OPG蛋白的表达情况。采用重复测量的方差分析方法,比较各组间在不同时间点的作用差异。结果：MTT结果,淫羊藿苷组具有促进人成骨细胞增殖的作用,并呈明显的量效关系,即随着淫羊藿苷浓度的增高,其促人成骨细胞增殖的能力增强,以10-6mol/L淫羊藿苷组（0.402±0.033）促成骨细胞增殖的作用最显著,与对照组（0.268±0.031）比较差异有统计学意义（P〈0.05）。在时效关系的研究中,随着培养天数的延长,人成骨细胞的量逐渐增加,人成骨细胞于第5天时进入快速生长期,第7天进入平台期;淫羊藿苷组从第5天开始促进人成骨细胞的增殖,第7、9天仍然具有明显的促成骨细胞增殖的作用,以第9天促增殖作用最强。其中,第9天10-6mol/L淫羊藿苷组（0.402±0.033）与对照组（0.268±0.031）比较有统计学意义（P〈0.01）。OPG表达结果,对照组人成骨细胞培养至第8天时检测到OPG蛋白的表达,表达量为1.01±0.08,第12天达到表达高峰为1.80±0.10,两个值比较有统计学差异（P〈0.05）;在观察的不同天数内,不同浓度的淫羊藿苷组人成骨细胞内OPG蛋白表达低于对照组,且随着淫羊藿苷浓度的降低,OPG蛋白的表达量逐渐降低,差异有统计学意义（P〈0.05）;干预12d,10-6mol/L淫羊藿苷组OPG量（1.67±0.13）和10-8mol/L淫羊藿苷组OPG量（1.64±0.05）比较,无统计学差异（P〉0.05）。结论：淫羊藿苷促人成骨细胞骨形成能力的作用途径之一,是通过提高人成骨细胞的增殖能力而实现。