不同剂量地塞米松对大鼠骨质量的作用

观察不同剂量地塞米松(Dex)对大鼠骨质量的影响并探讨其作用机制。31只3月龄SPF级雌性SD大鼠随机分为4组:对照组(saline 7只)、Dex-L组(1 mg/kg 8只)、Dex-M组(2.5 mg/kg 8只)、Dex-H组(5 mg/kg 8只);尾静脉注射Dex,2次/周,8周后处死。取胫骨上段制作不脱钙骨切片进行骨形态计量学分析,取左侧尺骨用于测定钙、磷和羟脯氨酸含量,股骨进行骨密度(BMD)和生物力学检测。结果表明:与对照组相比,Dex各组体重均显著下降;胫骨荧光周长百分率、矿化沉积率、骨形成率等显著降低,骨小梁面积百分数,骨小梁数目显著增加,骨小梁分离度显著减少;Dex-L BMD和Dex-M羟脯氨酸含量明显下降,Dex各组力学参数显著降低。提示:Dex显著抑制骨形成,降低骨转换,随着剂量增加,骨小梁面积百分数增加,BMD和骨生物力学性能下降,同时骨内有机质合成降低,非矿化骨形成增加,骨质量降低。以1 mg/kg的Dex对骨的质量影响最明显,该剂量略增加骨小梁面积百分数,但骨形成、骨生物力学性能、骨内有机质含量明显下降。不同剂量的Dex对骨质量的影响不同,剂量与骨质量之间无比例依赖关系。     

高冲击运动时不同着陆姿势对骨密度和骨矿含量的影响

目的研究不同类型高冲击运动对于骨密度(bone mineral density,BMD)和骨矿含量(bone mineral content,BMC)的影响。方法招募39名志愿者,其中伞兵、篮球运动员和作为对照组的普通大学生各13名,将其分成两组(第1组:20~22岁;第2组:23~25岁),分别测量跟骨、第1~5跖骨、髋关节和腰椎(L1~4)BMD和BMC。结果篮球运动员跟骨、第1、2跖骨、总腰椎和髋部BMC显著大于伞兵和对照组;篮球运动员在腰椎、髋关节和股骨颈处BMD也显著大于其他组;伞兵和对照组在测量部位的BMD和BMC无显著性差异。结论 BMC与BMD并非总是正比于平时运动时的垂直地面反作用力。相比跳伞训练,篮球运动能更好提高BMC和BMD,这种变载荷运动作为训练方法,更有利于降低骨质疏松性骨折的风险。     

中等强度运动训练结合仙灵骨葆胶囊对去势大鼠骨代谢的影响

目的 观察中强度运动训练结合仙灵骨葆胶囊对去卵巢大鼠骨密度（bone mineral density, BMD）、骨代谢及股骨生物力学的影响,为防治骨质疏松提供实验室参考。方法 50只雌性SD大鼠随机分为5组,每组10只。A组为正常对照,B组切除卵巢1周后灌胃给予1 mL生理盐水,C组切除卵巢1周后进行中等强度的运动训练（运动速度为20 m/min,每天持续时间为60 min,连续5 d/周）,D组切除卵巢1周后灌胃给予1 mL仙灵骨葆胶囊［0.4 g/(kg·d)］,E组切除卵巢1周后灌胃给予1 mL仙灵骨葆胶囊+中等强度的运动训练,连续治疗8周后,进行血液生化指标检测,以及股骨、L5椎体BMD、Micro-CT检测与生物力学检测。结果 与B组比较,C～E组的血液生化指标均有不同程度的改善,L5椎体、股骨骨密度升高,股骨（或L5椎体）的骨体积分数、骨小梁数目、骨小梁厚度升高,骨小梁间隙与结构模型指数降低,L5椎体最大载荷、最大挠度及最大应力升高,股骨最大载荷、弹性载荷、弹性挠度、弹性模量、弹性应力、最大应力及弹性挠度升高,其中均以E组效果最明显。结论 中等强度运动训练结合仙灵骨葆胶囊治疗可提升去卵巢大鼠BMD,改善骨代谢与骨微结构,提高骨力学性能,两者具有协同作用。     

仙珍骨宝干预泼尼松诱发大鼠的骨丢失

背景：仙珍骨宝胶囊由蛇床子、淫羊藿等制成,对糖皮质激素、维甲酸等诱发的骨质疏松有一定的预防作用。 目的：建立泼尼松诱发大鼠骨质疏松模型,通过骨形态计量学和骨生物力学等方法探讨仙珍骨宝对大鼠不同部位骨骼的影响。 方法：32只SD大鼠随机分成对照组、模型组和仙珍骨宝高、低剂量组。后3组给予泼尼松3.5 mg/(kg•d)灌胃建立骨质疏松模型。仙珍骨宝高、低剂量组大鼠在泼尼松灌胃1 h后给予仙珍骨宝胶囊0.95 g/(kg•d)、0.475 g/(kg•d)。 结果与结论：与对照组比较,模型组大鼠股骨骨密度、弹性载荷、最大载荷和断裂载荷均下降,胫骨上段动态参数标记周长百分数、骨表面形成率、骨转换率均降低,但静态参数骨小梁面积百分数、骨小梁数量、骨小梁厚度和骨小梁分离度无明显变化。胫骨中段皮质骨形态计量学参数均无明显变化。与模型组比较,仙珍骨宝高剂量组股骨密度、骨生物力学参数,胫骨上段标记周长百分数、骨表面形成率和骨转换率增加,但胫骨中段的骨形态计量学参数无明显变化。与模型组比较,仙珍骨宝低剂量组各项参数均无明显变化。提示高剂量仙珍骨宝促进骨形成,可预防泼尼松所致大鼠股骨骨密度及生物力学的降低,但对胫骨中段皮质骨无明显影响。     

DXA检测糖尿病性骨质疏松大鼠骨密度的部位选择

目的:通过观察糖尿病性骨质疏松大鼠模型骨密度(BMD)下降部位随时间的变化规律,探讨双能X线BMD仪(DXA)检测糖尿病性骨质疏松大鼠BMD的最佳部位。方法:选取无特定病原体级雌性3月龄SD大鼠30只,采用数字表法随机分成对照组和Ⅰ型糖尿病(T1DM)组,每组15只。对照组不做任何处理,T1DM组一次性腹腔注射链脲佐菌素50mg/kg,制作T1DM大鼠模型。应用DXA每月测定一次全身及局部感兴趣区BMD。3月末处死大鼠,测定离体腰椎、股骨等感兴趣区的BMD。结果:与对照组相比,T1DM组大鼠各腰椎和股骨各段的BMD随时间变化均有明显下降;与离体BMD相比,T1DM组大鼠腰椎L2-L5和股骨远心端的BMD最稳定,而腰椎L1、L6在体BMD和离体BMD相差较大。结论:腰椎的L2-L5和股骨远心端为DXA测量T1DM骨质疏松大鼠BMD的最佳部位。     

绝经后骨质疏松症模型体视学测量和机理初探

目的:观测去势术后大鼠骨组织体视学的改变,复制绝经后骨质疏松症的动物模型,初步探讨骨质疏松症的发病机制。方法:将31只3月龄雌性SD大鼠随机分为卵巢切除术组(OVX)和假手术组(sham),术后28d和56d分别处死。测量子宫湿重,骨矿物密度(BMD)和骨组织形态计量参数,分析骨组织微结构的变化。结果:OVX组术后28d和56d大鼠子宫湿重和股骨远端1/3处骨密度均显著少于sham组(P＜0.05);OVX组股骨远端和胫骨近端的干骺端骨小梁面积百分率显著少于sham组(P＜0.01)。结论:卵巢切除术后大鼠股骨远端骨矿物密度和骨组织形态计量学参数稳步下降,胫骨近端骨矿物密度和骨组织形态计量学参数迅速下降而且不稳定;雌激素减少导致的骨质疏松主要发生在长骨的干骺端,骨骺受影响较少;骨组织形态计量参数中骨小梁面积百分比敏感性和稳定性较高。     

DXA、力学测试和矿盐含量评估大鼠股骨性能的精确性比较

目的 为深入了解DXA、力学测试和矿盐含量在航天骨丢失研究的应用,本文比较了这三种方法评估大鼠股骨性能的精确性,并比较了大鼠股骨在活体、离体和冷冻三种情况下的DXA测量差别.方法 选择3只雄性SD大鼠,首先对其两侧股骨进行DXA测量,得到活体、离体和冷冻三种情况的骨矿密度(BMD),然后进行力学测试和矿盐含量测试.结果 DXA、力学测试和矿盐含量的变异系数(CV)分别为7.5%～8.5%,10.1%～17.1%和0.8%.对于DXA测量,活体股骨BMD值与离体和冷冻股骨BMD值都有极其显著差别(P＜0.001),而离体与冷冻股骨BMD值无显著性差别.结论 矿盐含量精确性好于DXA和力学测试.DXA测量活体与离体骨骼差别很大,冷冻不会影响DXA测量.     

仙珍骨宝抗泼尼松致大鼠松质骨结构破坏的作用

目的观察仙珍骨宝对糖皮质激素引起松质骨结构破坏的防治作用。方法选用3月龄SD雄性大鼠24只,随机分为对照组、激素组和治疗组。激素组用泼尼松4.5mg/kg灌胃,每周2次。治疗组给予100%仙珍骨宝5ml/kg,每周6次,持续90d。用骨组织形态计量学方法测算胫骨近端骨小梁的静态指标,并在扫描电镜下观察大鼠腰椎松质骨结构的改变。结果与正常组比较,激素组的大鼠胫骨的骨小梁的面积减少72.43%,骨小梁数目减少74.09%。腰椎的骨小梁变少,变细,断裂,连接不紧密,表面常见骨吸收形成的陷窝。治疗组大鼠胫骨骨小梁的面积比激素组增加179.70%,骨小梁数目增多187.60%。腰椎的骨小梁较粗大,排列整齐,连接紧密。结论仙珍骨宝能有效防止糖皮质激素所引起的松质骨三维结构的损害,保持骨的正常力学强度,避免骨折。     

去卵巢联合糖皮质激素诱发兔骨质疏松模型的研究

目的建立去卵巢联合糖皮质激素致兔骨质疏松模型,探讨去卵巢联合糖皮质激素对兔骨代谢的影响。方法将18只新西兰雌兔随机分为3组:假手术组(SHAM,生理盐水5 ml·kg-1·d-1);去卵巢组(OVX,生理盐水5 ml/kg/d);去卵巢联合糖皮质激素组(OVX+GC,地塞米松1 mg·kg-1·d-1)。实验第0、3和6周,检测各组大白兔腰椎(3~6)和右侧股骨的骨密度。实验结束时,取右侧股骨进行生物力学检测;取第3腰椎进行骨组织形态计量学检测。结果与SHAM组相比,OVX+GC组大白兔骨密度、骨生物力学性能(最大载荷、断裂载荷等)、骨小梁面积百分数、骨小梁厚度和骨小梁数量均显著降低(P<0.05),骨小梁分离度显著升高(P<0.05),而OVX组大白兔的均无显著差异。结论去卵巢联合糖皮质激素法建立兔骨质疏松模型切实可行,而且效果优于单纯去卵巢兔骨质疏松模型。     

糖皮质激素作用下大鼠股骨远端松质骨超微结构改变:扫描电镜观察结果

背景:骨质疏松症中骨微结构的破坏是导致骨强度下降、骨脆性增加以及骨折发生率增加的重要原因。目的:通过扫描电镜观察糖皮质激素作用下大鼠股骨远端松质骨超微结构的改变。方法:3.5月龄SPF级雌性SD大鼠32只,随机分为2组,糖皮质激素组皮下注射甲泼尼龙3.5mg/(kg·d)诱导糖皮质激素性骨质疏松,对照组皮下注射等量生理盐水。分别于干预4,9周后取大鼠股骨远端沿冠状面切开,蒸馏水冲洗骨髓腔,乙醇梯度脱水,表面喷金后利用扫描电镜观察大鼠股骨远端松质骨超微结构的改变。结果与结论:与对照组相比,糖皮质激素组大鼠骨小梁数目减少,且骨小梁变细、变脆、连接中断,立体网状结构破坏,同时骨吸收面积增加,骨胶原排列紊乱,骨微损伤增加,且糖皮质激素干预4周组较干预9周组能更好地保持骨微结构。提示糖皮质激素可导致大鼠松质骨的骨量减少、骨三维网状结构破坏、骨吸收活动增强,从而导致骨脆性增加,骨生物力学性能下降。     

二甲双胍改善糖尿病模型大鼠腰椎与后肢骨强度作用的差异

文题释义： 骨强度：综合反映骨量和骨质量,能较全面地评价骨的生物力学特征,评价骨的抗破坏和抗变形能力。 二甲双胍：为双胍类口服降血糖药。具有多种作用机制,包括延缓葡萄糖由胃肠道的摄取,通过提高胰岛素的敏感性而增加外周葡萄糖的利用,以及抑制肝、肾过度的糖原异生。该药不降低非糖尿病患者的血糖水平。患者用药期间体质量通常减轻,血浆胆固醇、三酰甘油和前β脂蛋白水平可降低,外周葡萄糖代谢能得到改善。 背景：研究证实二甲双胍对骨代谢有一定的调节作用,但其对骨强度的作用研究在国内仍未报道。 目的：观察二甲双胍改善糖尿病大鼠腰椎、后肢骨强度的作用差异。 方法：实验方案经广州中医药大学第一附属医院动物实验伦理委员会批准。30只大鼠随机挑选6只为空白组,24只大鼠6周高糖高脂饮食后,给予链脲佐菌素(40 mg/kg)一次性腹腔注射建立 2型糖尿病大鼠模型,从中挑选造模成功12只分为模型组及二甲双胍组。二甲双胍组300 mg/(kg▪d)二甲双胍悬浊液2 mL灌胃,1次/d;空白组和模型组用0.9%氯化钠溶液2 mL灌胃,1次/d;各组均给药12周。分别于给药后8,12周检测各组大鼠腰椎、股骨及胫骨最大载荷及弹性模量,计算给药12周时二甲双胍对中轴骨及外周骨的最大载荷改善率。 结果与结论：①二甲双胍组给药8,12周后对胫骨最大载荷均升高,给药12周后对腰椎、股骨最大载荷亦升高(P < 0. 05);②给药12周后,二甲双胍组腰椎及胫骨弹性模量均高于模型组(P < 0.05);③给药12周后,二甲双胍组腰椎最大载荷改善率为38.35%,股骨最大载荷改善率为24.05%,胫骨最大载荷改善率为14.70%;④结果说明,二甲双胍对糖尿病大鼠腰椎、后肢的骨强度均有一定改善作用,且对中轴骨(腰椎)的骨强度改善作用可能优于外周骨(股骨、胫骨)。 ORCID: 0000-0002-2340-111X(余佩沅) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

High physiological prolactin induced by pituitary transplantation decreases BMD and BMC in the femoral metaphysis, but not in the diaphysis of adult female rats

High physiological prolactin (PRL) stimulated intestinal calcium absorption and renal calcium uptake in mammals. Previous histomorphometric study revealed a significant increase in bone turnover in the trabecular part of the PRL-exposed long (cortical) bone; however, whole-bone densitometric analysis was unable to demonstrate such effect. We therefore studied differential changes in bone mineral density (BMD) and contents (BMC) of the femoral diaphysis and metaphysis in adult female rats exposed to high PRL induced by anterior pituitary (AP) transplantation. The estrogen-dependent effects of PRL on the femur were also investigated. We found that chronic exposure to PRL had no effect on BMD or BMC of the femoral diaphysis, which represented the cortical part of the long bone. It is interesting that 7 weeks after an AP transplantation, BMD and BMC of the femoral metaphysis were significantly decreased by 8% and 14%, respectively. Ovariectomy (Ovx) for 2, 5, and 7 weeks also decreased BMD and BMC in the femoral metaphysis, but not in the diaphysis. However, the AP transplantation plus Ovx (AP+Ovx) produced no additive effects. Nevertheless, 2.5 microg/kg 17beta-estradiol (E2) supplementation abolished the osteopenic effects of both Ovx and AP+Ovx on the femur. As for the L5-6 vertebrae, BMD and BMC were not affected by PRL exposure, but were significantly decreased by Ovx and AP+Ovx, and such decreases were completely prevented by E2 supplementation. It could be concluded that high physiological PRL induced a significant osteopenia in the trabecular part, i.e., the metaphysis, of the femora of adult female rats in an estrogen-dependent manner. Since PRL had no detectable effect on the vertebrae, the effects of PRL on bone appeared to be site-specific.     

康力龙对类固醇性大鼠骨质疏松骨密度和生物力学的影响

目的　从生物力学和骨矿含量测定角度研究康力龙对类固醇性大鼠骨代谢的影响。方法　采用 3月龄雄性SD大鼠 2 8只 ,随机分为基础对照组、年龄对照组、激素模型组和康力龙预防组。后两组给醋酸泼尼松 4 5mg·kg-1,ig ,2次 /周 ;预防组还给康力龙 0 5mg·kg-1·d-1,ig。 3个月后取股骨和第 5腰椎行骨密度测定 ,再行扭转、3点弯曲和压缩试验。结果　与年龄对照组比较 ,激素模型组股骨和第 5腰椎的总骨密度减少了 14 6 4 % (P <0 0 1) ;股骨干在 3点弯曲试验时所承受的载荷减少了17 1% (P <0 0 5 ) ;其余的力学参数都出现减少的趋势。与激素模型组比较 ,康力龙预防组股骨和第 5腰椎的总骨密度有所增加 ;股骨扭转角度明显增加 72 5 % (P <0 0 5 ) ,其余的力学参数都出现增加的趋势。结论　长期使用糖皮生激素 (GC) ,会使大鼠皮质骨和松质骨的骨密度和力学性能下降 ,从而易致骨折 ;应用康力龙则能阻止GC所致骨量丢失 ,还能增加其力学性能。     

The effects of fructo-oligosaccharides in combination with soy protein on bone in osteopenic ovariectomized rats

OBJECTIVE: The intestinal microflora is important in rendering soy isoflavones bioavailable by facilitating their conversion to equol. Hence, substances that can modulate the intestinal microflora could affect the bioavailability of isoflavones. In this study, we examined the effects of fructo-oligosaccharides (FOS), a prebiotic, on enhancing the effects of soy isoflavones on bone in ovariectomized osteopenic female rats. DESIGN: Sixty-three 9-month-old female Sprague-Dawley rats were either sham-operated (Sham; one group) or ovariectomized (Ovx; four groups) and were fed a control diet for 3 months to induce bone loss. After bone loss was confirmed via dual-energy x-ray absorptiometry, rats were placed on dietary treatment for 4 months. The Sham and one Ovx group received a control diet, and the remaining Ovx groups received either a soy protein-based diet (Soy), a FOS-supplemented diet (FOS), or a soy protein-based and FOS-supplemented diet (Soy+FOS). Before the termination of the study, whole-body bone mineral density (BMD) and bone mineral content (BMC) were assessed under anesthesia. Immediately after euthanasia, bone specimens were collected for the assessments of BMD, BMC, and biomechanical and microarchitectural properties. RESULTS: Whole-body BMD values were significantly higher in FOS and Soy+FOS groups compared with Ovx controls. The tibial BMC increased by 10%, 6%, and 4% in Soy, FOS, and Soy+FOS groups, respectively, compared to the Ovx control group. FOS and FOS+Soy treatments had the most pronounced effects in enhancing lumbar BMC and BMD. The FOS+Soy combination effectively improved tibial microarchitectural properties by enhancing trabecular number and lowering trabecular separation compared with Ovx controls. The effects of dietary treatments on lumbar microarchitectural properties were minimal and biomechanical properties of the femur were not affected by any of the dietary treatments. CONCLUSION: Our findings suggest that, although incorporation of either soy or FOS in the diet of Ovx rats can improve BMD of the whole body, tibiae, and lumbar vertebrae, their combination had no any additive effects. However, in terms of microarchitecture, the combination of soy and FOS had a greater effect in reversing the loss of certain microarchitectural parameters such as tibial trabecular number, separation, and thickness.     

Effects of resistance exercise training on mass, strength, and turnover of bone in growing rats

To determine the effects of resistance exercise on mass, strength and local turnover of bone, 50 Sprague Dawley rats, 8 weeks of age, were assigned to five groups: a baseline control and two groups of sedentary and exercising rats. The trunk of the rats was kept upright during electrically stimulated jumping exercise for 1 h every other day. In 4 weeks, the trabecular mineralizing surface per bone surface (MS/BS), bone formation rate per bone surface (BFR/BS) and the compression load of the lumbar body increased and the number of osteoclasts decreased, but bone mineral density (BMD) and structure did not increase. In the mid femur, the cross-sectional area, the cortical bone area, the moment of inertia, the periosteal MS/BS, BFR/BS and the bending load increased in the exercise group. In 8 weeks, the increases in BMD, structure and load values were significant in both the lumbar and mid femur. At both 4 and 8 weeks, the MS/BS for the endocortical surface of mid femur were not increased and mineral apposition rate (MAR) remained reduced. These results show that jumping exercise increases the mass and strength of the lumbar vertebrae and mid femur by stimulating bone formation and accelerates cortical drift by both increasing periosteal bone formation and reducing the endocortical MAR. Accepted: 1 February 2000     

Establishing a rapid animal model of osteoporosis with ovariectomy plus low calcium diet in rats

The objective of this study was to rapidly develop osteoporotic model animals by combining ovariectomy with a low calcium diet in rats. Thirty, eight-week-old, female, Sprague-Dawley rats were either sham-operated (Sham) or ovariectomized (Ovx) and divided into three groups: Sham, Ovx, and Ovx + low calcium diet. Rats in the Sham and Ovx groups were fed a standard diet containing 1.1% w/w calcium while rats in the Ovx + low calcium diet group were fed a diet containing 0.1% w/w calcium. Serum osteocalcin and bone mineral density (BMD) of the lumbar vertebrae were measured 4 and 8 weeks after surgery. The rats were euthanized 12 weeks after surgery, and the BMD of the right femur and histomorphometry of the femoral neck were assessed at that time. The Ovx + low-calcium diet group had a significantly lower mean BMD of the lumbar vertebra and higher mean serum osteocalcin concentration than the Sham and Ovx groups. Twelve weeks after surgery, rats in the Ovx + low calcium diet group had a significantly lower BMD, smaller Tb.Th and Tb.N, and larger Tb.Sp of the right femoral neck than did rats in the Sham and Ovx groups. These data indicate that a low calcium diet can significantly accelerate bone loss in ovariectomized rats. Combining ovariectomy and a low calcium diet can save considerable time in the creation of osteoporotic model animals.     

Effects of glucocorticoid on BMD, micro-architecture and biomechanics of cancellous and cortical bone mass in OVX rabbits

The incidence of osteoporosis continues to increase with progressively aging populations. The purpose of this study was to detect the effects of glucocorticoid (GC) treatment on bone mineral density (BMD), biomechanical strength and micro-architecture in cancellous and cortical bone in ovariectomized (OVX) rabbits. Twenty adult female New Zealand white rabbits were randomly divided into three groups. The OVX-GC group (n=8) received a bilateral ovariectomy first and then daily GC treatment (methylprednisolone sodium succinate, 1mg/kg/day) for 4 weeks beginning 2 weeks after ovariectomy treatment. The OVX group (n=4) received a bilateral ovariectomy without GC treatment. The sham group (n=8) only received the sham operation. BMD was determined prior to and 6 weeks after the operation in the spine. Six weeks after the operation, the animals were sacrificed, and cancellous bone specimens were harvested from the femoral condyle and lumbar vertebrae. Cortical bone specimens were obtained from the femoral midshaft. The femoral specimens were scanned for apparent BMD. All specimens were tested mechanically and analyzed by microcompute tomography (micro-CT). In cancellous bone, GC treatment resulted in significant decreases in BMD, bone biomechanical strength and micro-architecture parameters in lumbar vertebrae. Similar trends in BMD and micro-architectural changes were also observed in the femoral condyle in the OVX-GC group compared with the sham group. However, there was no significant decline in any parameter in either lumbar vertebrae or femoral condyle in the OVX group. Similarly, no significant difference was found in any parameter in cortical bone among the three groups. Thus, the 4-week GC treatment in OVX rabbits could result in a significant bone loss in cancellous bone but not in cortical bone. This model is comparable to the osteoporosis-related changes in humans. OVX alone was not sufficient to induce osteoporosis.     

丹皮酚对去卵巢骨质疏松大鼠叉头框蛋白O3a/Wnt信号通路及椎骨密度的影响

背景:丹皮酚可抑制炎症,减轻慢性骨关节炎临床症状,作为一种不良反应小、更为安全的天然药物成分,探讨其对骨质疏松症的治疗作用具有重要的临床意义。目的:探究丹皮酚对去卵巢骨质疏松大鼠叉头框蛋白O3a(forkhead box O3a,FoxO3a)/Wnt信号通路及椎骨密度的影响。方法:雌性SD大鼠随机分为6组,每组10只。假手术组仅切除卵巢旁部分脂肪组织;其余50只大鼠均采用双侧卵巢摘除法制备去卵巢骨质疏松大鼠模型,模型制备成功后分为模型组、雌激素组[炔雌醇10μg/(kg·d)]、丹皮酚低、中、高剂量组[丹皮酚125,250,500 mg/(kg·d)],每组10只,灌胃给药;假手术组、模型组灌胃等量生理盐水,持续干预12周。ELISA法测定血清雌激素、骨保护素、骨钙素水平;采用双能X射线动物骨密度测定仪检测大鼠股骨及椎骨骨密度;采用骨科生物力学测试仪检测大鼠股骨及椎骨生物力学指标:弹性模量、最大载荷、屈服载荷;实时荧光定量PCR检测椎骨组织FoxO3a、Wnt2 mRNA表达水平;免疫印迹法检测椎骨组织FoxO3a、Wnt2及核内β-catenin蛋白表达。结果与结论:①治疗后,与假手术组比较,模型组L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平均显著降低(P<0.05),骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平显著增加(P<0.05);②与模型组比较,丹皮酚低、中、高剂量组大鼠L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平依次增加(P<0.05),血清骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平依次降低(P<0.05),且丹皮酚高剂量组均优于雌激素组(P<0.05);③提示丹皮酚可增加去卵巢骨质疏松大鼠椎骨骨密度,改善其骨生物力学状况,减轻骨质疏松,该作用可能与抑制FoxO3a、促进Wnt2/β-catenin通路激活有关。     

Heterogeneity of growth of bone in children at the spine, radius and total skeleton.

Bone mineral content (BMC), density (BMD), and size were measured in 202 subjects ranging from 3 to 25 years of age (106 males and 96 females), half of which were children and half young adults. BMC and BMD were measured using single photon absorptiometry at the proximal and distal radius and dual photon absorptiometry at the lumbar spine and the total body. In the pre-pubertal age group (3-9 yrs), no differences were found in BMC nor BMD between males and females at any site. Growth of bone during puberty was characterized by an increase in BMC, bone size and BMD. The percent increase in BMC was greater at the lumbar spine and the total body (+200 to +390 %) than at the radius (+90 to +270 %). The increase in BMC was higher than the increase in BMD (+50 to +90 %). Overall bone growth in the total body was not reflected by changes in BMC of the appendicular skeleton. The increase in BMD was heterogeneous and was higher in the legs than in the arms. In males, the increase in BMC and size during growth was greater than in females resulting in a higher peak bone mass and size in males. The increase in BMD was similar between males and females at the distal radius, the lumbar spine and the total body, but higher at the proximal radius, the arms and the legs in males.(ABSTRACT TRUNCATED AT 250 WORDS)