Um dos mais importantes achados dos últimos anos foi o de que o remodelamento ósseo está sujeito ao controle do SNC, com o SNS agindo como efetor periférico. Um estudo do nosso grupo demonstrou que camundongos <font face=\"Symbol\">a2A/<font face=\"Symbol\">a2C-AR-/- apresentam um fenótipo de alta massa óssea, como também são resistentes à osteopenia induzida pelo excesso de hormônio HT. Com o intuito de verificar a participação do <font face=\"Symbol\">a2A-AR-/- nestes processos, tivemos como objetivos: caracterizar o fenótipo ósseo de camundongos <font face=\"Symbol\">a2A-AR-/- e avaliar o efeito do HT na estrutura óssea desses camundongos tratados. Pudemos observar que o comprimento longitudinal dos ossos dos animais <font face=\"Symbol\">a2A-AR-/- são menores do que dos animais selvagens e a análise por <font face=\"Symbol\">mCT do fêmur mostrou uma diminuição da porosidade da cortical. Com relação ao tratamento com hormônio tireoideano, os animais <font face=\"Symbol\">a2A-AR-/- tratados com T3 foram resistentes à diminuição do comprimento dos ossos causado pelo excesso de HT e vimos, ainda, que o osso trabecular dos animais <font face=\"Symbol\">a2A-AR-/- foi mais sensível aos efeitos deletérios da tirotoxicose, entretanto o osso cortical e parâmetros biomecânicos ósseos dos animais KOs foram menos sensíveis. Em conclusão, o presente estudo sugere que o <font face=\"Symbol\">a2A-AR está envolvido no processo de crescimento ósseo e que esse receptor possa mediar, pelo menos parcialmente, ações negativas do T3 nesse processo como também do HT no osso cortical. / One of the most important finds of the recent years is that bone remodeling is subject to the control of the CNS, with SNS acting as the peripheral effector. However, a recent study of our group showed that mice <font face=\"Symbol\">a2A/<font face=\"Symbol\">a2C-AR-/- have a high bone mass phenotype, even though are resistant to the thyroid hormone-induced osteopenia. In order to verify the role of <font face=\"Symbol\">a2A-AR-/- in these cases, we had as objectives to evaluate whether the isolated inactivation of <font face=\"Symbol\">a2A-AR interferes with the bone structure, and to evaluate the action of HT on these animals. We have observed that the longitudinal length of the bones of <font face=\"Symbol\">a2A-AR-/- animals are lower than those of wild type animals and the analysis of the femur by <font face=\"Symbol\">mCT showed a lower cortical porosity. With regard to treatment with thyroid hormone, we observed that <font face=\"Symbol\">a2A-AR-/- animals were resistant to the bone length decrease caused by thyroid hormone excess. We also noticed that the trabecular bone of <font face=\"Symbol\">a2A-AR-/- animals was more sensitive to the deleterious effects of thyrotoxicosis. Moreover, the cortical bone and bone biomechanical parameters KO animals were less sensitive. In conclusion, the findings of this study suggest that <font face=\"Symbol\">a2A-AR is involved in the process of bone growth and that this receptor may mediate at least partly, negative actions of T3 in this process as well as the HT in the cortical bone.

Resumo: A poliuretana derivada do óleo de mamona propicia estimulação na reparação óssea por apresentar propriedades de osteocondutividade auxiliando na neoformação óssea. Quanto a osteoindução, pode ser estimulada por fatores de crescimento, como a BMP, e por fatores físicos como o laser. O trabalho avaliou a regeneração óssea a partir da confecção de uma lesão na base da mandíbula de rato, preenchida com mamona particulada, acrescida do "pool" de BMP E Hidroxiapatita (HA) absorvível. Posteriormente aplicou-se ou não um estímulo local com o laser de baixa intensidade. O aparelho utilizado foi o Laser beam (Semicondutor de Arseneto de Gálio-Alumínio, infravermelho - 785nm, 35mW). Foram usados 60 ratos Holtzman, divididos em quatro grupos de 15 animais, e estes subdivididos em 5 animais por período de análise, da seguinte forma: Grupo Controle (somente defeito); Grupo Experimental com estimulação laser (dose=178J/cm2; energia=1,4J); Grupo Experimental com mamona particulada acrescido de (BMP-HA); Grupo Experimental com mamona particulada acrescido de (BMP-HA), e estimulação laser (dose=178J/cm2; energia=1,4J). Os ratos foram sacrificados nos períodos de 15,45 e 60 dias; as mandíbulas foram removidas e processadas para inclusão em parafina, e os cortes de 6um foram corados por H&E, Tricrômico de Massom e Picro sirius. Os resultados histológicos mostraram formação óssea em todos os grupos. Nos grupos com o laser, a resposta tecidual foi antecipada em relação aos demais grupos promovendo a rápida neoformação da matriz óssea. / Abstract: It suggest that polyurethane achieved from (Ricinus communis) induces bone repair because their osteoconductivity properties. In concerning the bone-inducing, that promotes osseous neoformation, it has been stimulate by growth factors, as bone morphogenetic protein (BMP), and laser therapy. The aim of this study was to evaluate osseous regeneration after mandible defects created in rats, and coveried with polyurethane resin partices (Ricinus communis), added with BMP and absorbable Hydroxyapatite (HA), stimulated or not by Laser beam. It was used the laser equipment "Laser beam" (Infra-red, continuous, Gallium-arsenide, 785nm, 35mW). Were utilized for this study 60 rats (Holtzman), were distributed in 4 groups of 15 animals. The control group (with only defect); the experimental group with laser stimulated (fluency=178J/cm2; energy=1,4J); the experimental group with resin particles added with (BMP-HA), and another similar group with laser stimulation (fluency=178J/cm2; energy=1,4J). The animals were then sacrified at the 15th, 45th and 60th days; mandibles were removed and processed for light microscopy. The histological examination samples were stain with H&E, Tricomic of Masson and Sirius Red. The results showed osseous neoformation in all groups. However, in the groups with laser stimulation the tissue response presented demonstrating earlier bone matrix formation. / Orientador: Lizeti Toledo de Oliveira Ramalho / Coorientador: Rosane de Fátima Zanirato Lizarelli / Banca: Hélio Ferraz Porciúncula / Banca: Maria Cristina Borsatto / Mestre

Wong Yin-Mei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 119-135). / Abstracts in English and Chinese. / Abstract (English version) --- p.i / Abstract (Chinese version) --- p.iii / Publications --- p.v / Acknowledgements --- p.vi / Table of contents --- p.viii / List of tables --- p.xi / List of figures --- p.xii / Abbreviations --- p.xiv / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Osteoporosis --- p.1 / Chapter 1.1.1 --- Consensus statement --- p.1 / Chapter 1.1.2 --- Epidemiology and outcomes --- p.4 / Chapter 1.1.2.1 --- Hip fractures --- p.4 / Chapter 1.1.2.2 --- Vertebral fractures --- p.5 / Chapter 1.1.2.3 --- Wrist fractures --- p.7 / Chapter 1.1.3 --- Postmenopausal osteoporosis --- p.8 / Chapter 1.1.3.1 --- Pathogenesis --- p.8 / Chapter 1.1.3.1.1 --- Genetics --- p.11 / Chapter 1.1.3.1.2 --- Bone remodeling --- p.14 / Chapter 1.1.3.1.3 --- Calcium homeostasis --- p.21 / Chapter 1.1.3.1.4 --- Life style 一 nutrition and exercise --- p.26 / Chapter 1.1.3.2 --- Current pharmacological treatment --- p.27 / Chapter 1.1.3.2.1 --- Introduction --- p.27 / Chapter 1.1.3.2.2 --- Limitations --- p.31 / Chapter 1.2 --- Traditional Chinese medicine --- p.33 / Chapter 1.2.1 --- The Kidney --- p.33 / Chapter 1.2.2 --- Kidney-tonifying herbs --- p.33 / Chapter 1.3 --- Aim of the studies --- p.36 / Chapter Chapter 2. --- Materials and methods --- p.38 / Chapter 2.1 --- Kidney-tonifying herbs and herbal formula --- p.38 / Chapter 2.1.1 --- Sources --- p.38 / Chapter 2.1.2 --- Herbal extract preparation --- p.38 / Chapter 2.2 --- Animal study --- p.40 / Chapter 2.2.1 --- Reagents --- p.40 / Chapter 2.2.2 --- Animal care --- p.40 / Chapter 2.2.3 --- Herbs and herbal formula preparations for animal studies --- p.41 / Chapter 2.2.4 --- Experimental design --- p.41 / Chapter 2.2.5 --- Gene expression study --- p.44 / Chapter 2.2.5.1 --- Tissue preparation --- p.44 / Chapter 2.2.5.2 --- Isolation of total RNA --- p.45 / Chapter 2.2.5.3 --- Complementary DNA synthesis --- p.47 / Chapter 2.2.5.4 --- Real-time polymerase chain reaction analysis --- p.47 / Chapter 2.3 --- Cell culture study --- p.49 / Chapter 2.3.1 --- Reagents --- p.49 / Chapter 2.3.2 --- Cell lines --- p.49 / Chapter 2.3.2.1 --- "Rat osteosarcoma cell line, UMR-106" --- p.49 / Chapter 2.3.2.2 --- "Human breast cancer cell line, MCF-7" --- p.50 / Chapter 2.3.2.3 --- Cell culture techniques --- p.50 / Chapter 2.3.3 --- Herbs preparations for cell culture --- p.51 / Chapter 2.3.4 --- Cell viability assay --- p.51 / Chapter 2.3.5 --- Cellular alkaline phosphatase activity assay --- p.52 / Chapter 2.3.6 --- Matrix mineralization assay --- p.54 / Chapter 2.3.7 --- Competitive estrogen receptor binding assay --- p.56 / Chapter 2.4 --- Statistical analyses --- p.58 / Chapter Chapter 3. --- Results --- p.59 / Chapter 3.1 --- Extraction yields of Kidney-tonifying herbs and herbal formula --- p.59 / Chapter 3.2 --- Effects of Kidney-tonifying herbs and herbal formula on the gene expressions of calcium absorption and reabsorption related genes --- p.61 / Chapter 3.2.1 --- Gene expression of 25-hydroxyvitamin D3-1 alpha-hydroxylasein the kidney --- p.62 / Chapter 3.2.2 --- Gene expression of vitamin D receptor in the duodenum --- p.65 / Chapter 3.2.3 --- Gene expression of calbindin D9K in the duodenum --- p.67 / Chapter 3.2.4 --- Gene expression of vitamin D receptor in the kidney --- p.69 / Chapter 3.2.5 --- Gene expression of calbindin D28K in the kidney --- p.71 / Chapter 3.3 --- Effects of Kidney-tonifying herbs on osteoblastic UMR-106 cell line --- p.73 / Chapter 3.3.1 --- Effects of Kidney-tonifying herbs on the cell viability of UMR-106 cells --- p.73 / Chapter 3.3.2 --- Effects of Kidney-tonifying herbs on the osteoblastic differentiation of UMR-106 cells --- p.76 / Chapter 3.3.2.1 --- Cellular alkaline phosphatase activity --- p.76 / Chapter 3.3.2.2 --- Degree of matrix mineralization --- p.80 / Chapter 3.4 --- Estrogen receptor binding activities of Kidney-tonifying herbs --- p.85 / Chapter Chapter 4. --- Discussion --- p.89 / Chapter 4.1 --- Safety of Kidney-tonifying herbs and herbal formula --- p.89 / Chapter 4.2 --- Kidney-tonifying herbs and herbal formula preserve bone mineral density --- p.93 / Chapter 4.3 --- Kidney-tonifying herbs and herbal formula modulate calcium homeostasis --- p.97 / Chapter 4.3.1 --- "Roles in renal synthesis of the hormonally active form of vitamin D: 1,25-dihydroxyvitamin D3" --- p.97 / Chapter 4.3.2 --- Roles in calcium absorption in the duodenum --- p.99 / Chapter 4.3.3 --- Roles in calcium reabsorption in the kidney --- p.102 / Chapter 4.3.4 --- Summary --- p.104 / Chapter 4.4 --- Kidney-tonifying herbs modulate bone formation --- p.106 / Chapter 4.4.1 --- Effects on osteoblast proliferation --- p.106 / Chapter 4.4.2 --- Effects on osteoblastic differentiation --- p.107 / Chapter 4.4.3 --- Summary --- p.108 / Chapter 4.5 --- Kidney-tonifying herbs interact with estrogen receptor --- p.110 / Chapter 4.6 --- Active ingredients of Kidney-tonifying herbs --- p.111 / Chapter 4.7 --- Limitations of the present studies --- p.115 / Chapter 4.8 --- Conclusion and future prospect --- p.117 / References --- p.119

傳統中醫中藥理論遵從"腎主骨"概念。因此，中醫在治療與骨有關的疾病時一般都處方"補腎"類中藥。 / ELP是一例中藥草本 "補腎" 複方。其包含三種中藥，包括淫羊藿（E）、女貞子（L）和補骨脂（P）。動物體內實驗和臨床研究已證明ELP有效治療絶經後骨質疏鬆症。可是，經口服吸收後的血清中的ELP有效物質對細胞的成骨影響從未進行過相關研究。ELP對預防在缺乏體力活動下所引起的骨質疏鬆症的療效也屬未知。此外，基於其"補腎"的特性，ELP可能潛在著能促進骨折癒合的功能。本研究的目的包括研究血清中ELP的有效物質在細胞和分子水平上的護骨能力，並測試其對預防於失重狀態下引起的骨質疏鬆症（慢性骨紊亂）的效能。本研究還旨在考察 ELP在促進骨癒合 （急性骨紊亂）上的作用。本研究分為三部分。 / 第一部分 -- 骨代謝的體外研究:健康大鼠分別口服草本配方ELP、EL、及單味中草藥提取物E或L、並以蒸餾水作為對照（H2O），口服給藥二小時後收集其血清作體外血清藥理學研究。分別考察含藥血清對各細胞系包括UMR106、RAW264.7、和從大鼠骨中分離出的骨髓間充質幹細胞（MSC）的增殖和分化屬性的影響，並以液質聯用技術（LC-MS）來分析血清內所含中藥的化學成份。 / 第二部分 -- 骨質疏鬆症的體內研究:以尾吊雄性大鼠作為卸荷狀態骨質疏鬆症的動物模型。在不同的給藥組中，大鼠口服高中低三種劑量的ELP（ELP-H、ELP-M和ELP-L），或三個不同抗骨質疏鬆藥物，包括雷洛昔芬（Ral），阿侖膦酸鈉（Aln）和雷奈酸鍶（Strn）作為陽性對照組，並以蒸餾水為安慰劑對照（TS）。另一組大鼠則沒有尾吊，作為正常對照（Non-TS）。本部分分析在吊尾期間大鼠體內生化指標和骨密度（BMD）的變化，及其後各組在骨小梁微結構和骨骼生物力學上的差異。 / 第三部分 -- 骨缺損癒合的體內研究:兩個鑽孔性骨缺損模型分別建立於老年雌性大鼠的左股骨骨幹和右脛骨近端骺端。其後動物分成4組：（1）ELP 口服給藥（ELP）；（2）CDNR外敷治療（CDNR為另一中藥複方，包含紅花（C）、續斷（D）、三七（N）和大黃（R））；（3）ELP口服給藥結合CDNR外敷治療（ELP+CDNR）；（4）和蒸餾水餵養（Control）。通過監測骨缺損癒合的過程、檢測大鼠血液中生化標誌物的變化、骨骼生物力學測試和形態計量學分析，考察ELP及其與CDNR在骨缺損癒合上的協同作用。 / 第一部分的結果顯示，口服給藥二小時後，大鼠血清中淫羊藿的標記化合物淫羊藿苷（icariin）無被檢出。在EL或E的給藥大鼠血清中，檢出淫羊藿苷的其中一個代謝產物icariside I；而其另一個代謝產物icariside II，則在ELP的給藥大鼠血清中檢測到。L和P的常見標記化合物則能從相應餵飼L和P的大鼠血清中檢出。體外血清藥理學研究結果表明含藥（ELP）大鼠血清對細胞無毒性作用，且能促進 UMR106 細胞增殖和上調其Runx2 基因表達。然而，含藥血清無增加UMR106細胞的鹼性磷酸酶活性和鈣沉積。它抑制 RAW264.7細胞的分化及其基質金屬蛋白酶9（MMP-9）和組織蛋白酶 K的基因表達。它亦能促進MSC細胞的增殖，增強其鹼性磷酸酶活性和Runx2與ALP基因的表達。 / 第二部分的結果指出ELP-H能減少吊尾大鼠股骨遠端及腰椎骨密度的百分比損失，抵抗股骨遠端骨小梁微結構惡化和加強股骨骨幹骨缺損部位的生物力學特性。此外，ELP-H還能降低血液骨鈣素和抗酒石酸酸性磷酸酶5b（TRAP5b）的濃度。研究亦發現ELP對骨密度、結構參數和生化指標的影響存在劑量依賴性。整體上而言，ELP在預防卸荷骨質疏鬆症的影響類似於Ral和Aln，而非Strn。 / 第三部分的結果表明，從顯微電腦掃描或形態計量學上分析，所有實驗組跟對照組間均沒有顯著性差異。但值得注意的是，ELP+CDNR大大提高了股骨骨幹骨缺損在癒合過程中的歸一化生物力學屬性。而ELP單獨用藥則減少了TRAP5b的濃度。 / 總之，這項研究結論出血清藥理學研究加上LC-MS的應用能作為找出中藥中有效成分的有效途徑。本研究還展示ELP的含藥血清對骨細胞有護骨作用。ELP可防預在卸荷狀態下形成的骨質疏鬆症，它還有助於提升外敷中藥複方CDNR在骨缺損癒合過程中的療效。從這項研究的三個部分中歸納出的共同點說明，儘管ELP擁有刺激成骨的能力，它的護骨作用主要是透過它的抗骨吸收效果。ELP在慢性（防止骨質疏鬆症）和急性（促進骨癒合）骨紊亂上均有療效。 / Traditional Chinese Medicine (TCM) claims that bone health lies in the functioning of the "Kidneys". When the "Kidney" is strong, our body can stimulate growth and transformation of the bone marrow, which nourishes and strengthens the skeleton. Therefore, "Kindey-tonifying" herbs are usually used to cure bone diseases. / ELP is a "Kidney-tonifying" Chinese herbal formula containing three Chinese herbs including Herba Epimedii (E), Fructus Ligustri Lucidi (L) and Fructus Psoraleae (P). It has been proven effective to treat postmenopausal osteoporosis through in vivo and clinical studies. However, ELP is for oral administration. The osteogenic properties of its post-absorption metabolites have never been studied. The efficacy of ELP on prevention of osteoporosis development due to physical inactivity is also unknown. With its "Kindey-tonifying" property, ELP is also considered as a potential agent to facilitate fracture healing. / The aims of this study included to investigate the osteoprotective effects of ELP metabolites at cellular and molecular levels and to prove the efficacy of ELP on prevention of osteoporosis development in unloading condition - a chronic bone disorder. It also aimed to study the effect of ELP on promotion of bone defect healing - an acute bone disorder. This study was divided into three parts. / Part 1 - in vitro study of bone metabolism: Healthy rats were fed with herbal formula ELP or EL, single herbal extracts of E or L or distilled water as control (H₂O). Sera were then collected for in vitro seropharmacological study. Cell lines including UMR106 and RAW264.7, as well as mesenchymal stem cell (MSC) isolated from rats, were cultured with the sera. Their proliferation and differentiation properties of the cells were analyzed. In addition, the chemical profiles of the herbal extracts within the sera were analyzed using liquid chromatography-mass spectrometry (LC-MS). / Part 2 - in vivo study of osteoporosis: Tail-suspension male rats were used as the unloading osteoporotic animal model. The rats in different groups were fed with three different doses of ELP (ELP-H, ELP-M and ELP-L), or three different anti-osteoporosis drugs including raloxifene (Ral), alendronate (Aln) and strontium ranelate (Strn) as positive controls or distilled water as placebo control (TS). One group of rats was non-tail-suspended as normal control (Non-TS). Changes in bone mineral density (BMD), microarchitecture of trabeculae and biomechanical properties of the bone of the rats were analyzed. Changes in biochemical markers within the tail-suspension period were also studied. / Part 3 - in vivo study of bone defect healing: two drilled-hole bone defects were created in the diaphysis of left femur and proximal metaphysis of right tibia, respectively, of aged female rats. Animals were divided into 4 groups: (1) administered with ELP orally (ELP); (2) treated with another herbal formula CDNR containing Carthami Flos (C), Dipsaci Radix (D), Notoginseng Rhizoma (N) and Rhei Rhizoma (R) topically (CDNR); (3) treated with oral ELP and topical CDNR at the same time (ELP+CDNR); and (4) fed with distilled water (Control). The effects of ELP and the synergistic effects of ELP+CDNR on facilitation of the bone defect healing were monitored in vivo using viva-CT and through measurement of biochemical markers biweekly. After euthanasia of the rats, the bones were harvested for biomechanical test and histomorphometrical analysis. / Results: Part 1 revealed that the common marker compound, icariin, had not been detected in the sera of all the rats. Instead, one of the metabolites of E, icariside I, was found in the sera of the rats fed with EL or E, while another metabolite, icariside II, was detected in the serum of the rats fed with ELP. Common marker compounds of L and P were observed in the sera of the rats fed with the herbal items accordingly. The in vitro studies in this Part showed that there was no cytotoxic effect of the rat sera on the cells. The post-absorbed ELP metabolites in rat serum promoted UMR106 proliferation by 25.7%, (p < 0.05) and upregulated the Runx2 gene expression by 1.18 fold (p < 0.05) after cultured for 2 and 3 days, respectively. However, they could not increase the ALP activity and calcium deposition of UMR106. They also inhibited RAW264.7 differentiation by 29.2 % (p < 0.05) and downregulated the MMP9 and Cathepsin K gene expression of RAW264.7 by 0.46 (p < 0.05) and 0.36 (p < 0.01) fold, respectively. The ELP metabolites promoted the proliferation of MSC by 14.4 % (p < 0.001) and resulted in 42.6 % higher ALP activity than the control serum (p < 0.05). They also upregulated the Runx2 and ALP gene expression at both Day 4 and Day 7 of culture significantly. / Part 2 showed that compared with the tail-suspension control (TS), ELP in high dose (ELP-H) reduced the percentage loss of total and trabecular BMD by 5.46 and 8.52 %, respectively (p < 0.05 both) in distal femur, and by 4.67 % (p < 0.05) in trabecular region of lumbar spine of the tail-suspended rats. Analysis from micro-CT showed that microarchitectural parameters BV/TV, Tb.Th and TV density of the distal femur of ELP-H were 17.62, 11.90 and 8.09 % higher than those of the TS (p < 0.05, for all). 3-point bending test on mid-shaft femur of the rats revealed that the yield load, ultimate load and stiffness of the drill-defect of ELP-H were higher than those of TS significantly. All of the biochemical markers decreased significantly from baseline (Day 0) to Day 28 in ELP-H. In addition, osteocalcin and TRAP5b concentrations of ELP-H were lower than those of TS significantly at Day 28. The effect of ELP on BMD, microarchitectural parameters and biochemical markers were in dose-dependent manner. In general, the osteoprotective effect of ELP-H on unloading bone was similar to Ral and Aln, but not Strn. / Part 3 indicated no significant difference in BV/TV and BMD among all groups at each time point. Histomorphometrical analysis from fluorescent labeling and Goldner’s trichrome staining showed no statistical difference in new bone formation between the Control and other treatment groups. Notably, the normalized yield load, ultimate load and failure of ELP+CDNR were significantly higher than those of Control by 20.38 % (p < 0.05), 23.17 % (p< 0.001) and 25.55 % (p< 0.001), respectively. Analysis on the change of biochemical markers showed that the bone formation marker BALP increased while bone resorption markers Dpd and TRAP5b decreased within the 42-day monitoring period. BALP activity of both Control and ELP increased significantly but only ELP reduced the TRAP5b concentrations starting from Day 14 post-op. There was no statistical difference when the concentrations of the biochemical markers were compared horizontally among the 4 groups at the same time point. / In conclusion, the current study demonstrated that seropharmacological study incorporating with the application of LC-MS can be a potential efficient approach to find out active ingredients of medicine herbs. Post-absorbed metabolites of ELP also showed their osteoprotective effects on bone cells. Aqueous extract of ELP could prevent the development of osteoporosis in unloading condition and such effect was dose-dependent. It also helped elevating the efficacy of a topical applied herbal formula CDNR on improving the bone strength of healing bone defects. A common finding from the 3 parts of this study illustrated that the osteoprotective effect of ELP was mainly achieved by its anti-resorptive efficacy on bone, although it possess an ability to stimulate osteoblastogenesis. ELP was found effective for both chronic (prevent osteoporosis development) and acute (facilitate bone healing) bone disorders. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Siu, Wing Sum. / "November 2012." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 201-227). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / ABSTRACT --- p.i / 摘要 --- p.vi / ACKNOWLEDGEMENTS --- p.ix / TABLE OF CONTENTS --- p.xi / LIST OF FIGURES --- p.xvii / LIST OF TABLES --- p.xxiii / PUBLICATIONS --- p.xxiv / ABBREVIATION --- p.xxv / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter 1.1 --- TRADITIONAL CHINESE MEDICINE (TCM) AND BONE DISEASES --- p.1 / Chapter 1.2 --- CELLULAR AND MOLECULAR MECHANISMS ON BONE METABOLISM --- p.2 / Chapter 1.2.1 --- Bone formation by osteoblast --- p.3 / Chapter 1.2.2 --- Bone resorption by osteoclasts --- p.4 / Chapter 1.3 --- OSTEOPOROSIS --- p.5 / Chapter 1.3.1 --- Postmenopausal osteoporosis --- p.6 / Chapter 1.3.2 --- Disuse osteoporosis --- p.8 / Chapter 1.3.3 --- Basic principle of TCM on osteoporosis --- p.10 / Chapter 1.3.4 --- Common Chinese herbal medicine reported to have anti-osteoporotic effects --- p.11 / Chapter 1.4 --- BONE FRACTURE --- p.11 / Chapter 1.4.1 --- Biology and repair of bone fracture --- p.12 / Chapter 1.4.2 --- TCM on promotion of fracture healing --- p.13 / Chapter 1.4.3 --- Theories of TCM on fracture healing --- p.15 / Chapter CHAPTER 2: --- OSTEOPOROSIS AND HERBS --- p.16 / Chapter 2.1 --- CHINESE HERBAL MEDICINE SELECTED IN THIS PART --- p.16 / Chapter 2.2 --- DESIGN OF STUDY --- p.19 / Chapter 2.3 --- HYPOTHESES AND OBJECTIVES --- p.19 / Chapter 2.4 --- BACKGROUND OF THE STUDY --- p.23 / Chapter 2.4.1 --- In vitro study of ELP on bone cells --- p.23 / Chapter 2.4.2 --- In vivo study of ELP on postmenopausal osteoporosis --- p.23 / Chapter 2.4.3 --- Clinical study of ELP on postmenopausal osteoporosis --- p.24 / Chapter CHAPTER 3: --- PART 1 IN VITRO SEROPHARMACOLOGICAL STUDY ON OSTEOPOROSIS --- p.26 / Chapter 3.1 --- OBJECTIVES --- p.26 / Chapter 3.2 --- SEROPHARMACOLOGICAL APPROACH TO STUDY ELP --- p.26 / Chapter 3.3 --- TYPES OF CELLS INVOLVED IN THE CURRENT STUDY --- p.27 / Chapter 3.3.1 --- UMR106 --- p.28 / Chapter 3.3.2 --- RAW264.7 --- p.28 / Chapter 3.3.3 --- Mesenchymal stem cell (MSC) --- p.28 / Chapter 3.4 --- IN VITRO ASSESSMENTS ON BONE METABOLISM --- p.29 / Chapter 3.4.1 --- Bone formation --- p.29 / Chapter 3.4.1.1 --- 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay --- p.29 / Chapter 3.4.1.2 --- Bromodeoxyuridine (BrdU) assay --- p.30 / Chapter 3.4.1.3 --- Total alkaline phosphatase (ALP) activity measurement --- p.30 / Chapter 3.4.1.4 --- Calcium deposition analysis --- p.30 / Chapter 3.4.2 --- Bone degradation --- p.31 / Chapter 3.4.2.1 --- Tartrate-resistant acid phosphatase (TRAP) staining --- p.31 / Chapter 3.4.3 --- Phenotypic markers of cells involved in bone remodeling using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR) --- p.31 / Chapter 3.5 --- MATERIAL AND METHODS --- p.37 / Chapter 3.5.1 --- Preparation of herbal extracts --- p.37 / Chapter 3.5.2 --- Serum preparation for seropharmacological study --- p.38 / Chapter 3.5.2.1 --- Administration of herbal extracts and blood collection --- p.38 / Chapter 3.5.2.2 --- Serum preparation --- p.38 / Chapter 3.5.3 --- Analysis of marker compounds in serum using liquid chromatographymass spectrometry (LC-MS) --- p.39 / Chapter 3.5.3.1 --- Serum preparation --- p.39 / Chapter 3.5.3.2 --- Operation of LC-MS --- p.39 / Chapter 3.5.4 --- Isolation and characterization of MSC from bone marrow --- p.40 / Chapter 3.5.5 --- Cell culture --- p.42 / Chapter 3.5.5.1 --- General materials --- p.42 / Chapter 3.5.5.2 --- UMR106 --- p.43 / Chapter 3.5.5.3 --- RAW264.7 --- p.44 / Chapter 3.5.5.4 --- Bone Marrow MSC --- p.45 / Chapter 3.5.6 --- Assays analyzing the responses of cells on the effect of metabolites of herbs in serum --- p.46 / Chapter 3.5.6.1 --- General materials --- p.46 / Chapter 3.5.6.2 --- Assays for bone formation --- p.50 / Chapter 3.5.6.3 --- Assays for bone degradation --- p.55 / Chapter 3.5.7 --- Statistical analysis --- p.56 / Chapter 3.6 --- RESULTS --- p.57 / Chapter 3.6.1 --- Chemical characterization of ELP extract --- p.57 / Chapter 3.6.2 --- Marker compounds found in rat serum using LC-MS --- p.58 / Chapter 3.6.3 --- Effects of herbal metabolites on UMR106 --- p.61 / Chapter 3.6.3.1 --- Effect on cell viability --- p.61 / Chapter 3.6.3.2 --- Effects on cell proliferation and differentiation --- p.61 / Chapter 3.6.3.3 --- Regulation on osteogenesis through gene expression --- p.63 / Chapter 3.6.4 --- Effects of herbal metabolites on RAW264.7 --- p.67 / Chapter 3.6.4.1 --- Effect on cell viability --- p.67 / Chapter 3.6.4.2 --- Inhibitory effect on RAW264.7 --- p.67 / Chapter 3.6.4.3 --- Regulation on osteoclastogenesis through gene expression --- p.67 / Chapter 3.6.5 --- Effects of herbal metabolites on bone marrow mesenchyma stem cell (MSC) --- p.70 / Chapter 3.6.5.1 --- Confirmation of MSC isolated from bone marrow of rat using flow cytometry --- p.70 / Chapter 3.6.5.2 --- Effect on cell viability --- p.70 / Chapter 3.6.5.3 --- Effects on cell proliferation and differentiation --- p.71 / Chapter 3.6.5.4 --- Regulation on osteogenesis through gene expression --- p.71 / Chapter 3.7 --- DISCUSSION --- p.75 / Chapter CHAPTER 4: --- PART 2 IN VIVO STUDY ON DISUSE OSTEOPOROSIS . --- p.83 / Chapter 4.1 --- OBJECTIVES --- p.83 / Chapter 4.2 --- POTENTIAL EFFECT OF ELP ON DISUSE OSTEOPOROSIS --- p.83 / Chapter 4.3 --- ANIMAL MODELS FOR OSTEOPOROSIS STUDY --- p.84 / Chapter 4.3.1 --- Conventional ovariectomized animal model for the studies of osteoporosis --- p.85 / Chapter 4.3.2 --- Animal models for study of disuse osteoporosis --- p.85 / Chapter 4.3.2.1 --- Bandaging or casting --- p.86 / Chapter 4.3.2.2 --- Tail-suspension (TS) --- p.86 / Chapter 4.4 --- ASSESSMENTS ON DISUSE OSTEOPOROSIS DEVELOPMENT --- p.87 / Chapter 4.4.1 --- Bone mineral density (BMD) measurement --- p.87 / Chapter 4.4.2 --- Micro-architecture analysis --- p.87 / Chapter 4.4.3 --- Bone strength assessment --- p.88 / Chapter 4.4.4 --- Bone turnover monitoring by measuring biochemical markers --- p.89 / Chapter 4.4.4.1 --- Bone formation markers --- p.89 / Chapter 4.4.4.2 --- Bone resorption markers --- p.91 / Chapter 4.5 --- MATERIAL AND METHODS --- p.95 / Chapter 4.5.1 --- Preparation of herbal extracts --- p.95 / Chapter 4.5.2 --- Tail-suspension rat model --- p.95 / Chapter 4.5.3 --- Animal arrangement and grouping --- p.97 / Chapter 4.5.4 --- Administration of herbal extracts and drugs --- p.97 / Chapter 4.5.5 --- Assessments on disuse osteoporosis development --- p.98 / Chapter 4.5.5.1 --- Bone mineral density measurement using Peripheral Quantitative Computed Tomography (pQCT) --- p.98 / Chapter 4.5.5.2 --- Bone micro-architecture analysis using Micro-computed Tomography (μCT) --- p.99 / Chapter 4.5.5.3 --- Bone strength assessment through biomechanical bending test --- p.100 / Chapter 4.5.5.4 --- Bone turnover monitoring by measuring biochemical markers --- p.100 / Chapter 4.5.5.4.1 --- Serum collection --- p.100 / Chapter 4.5.5.4.2 --- Measurements of biochemical markers --- p.101 / Chapter 4.5.6 --- Statistical analysis --- p.105 / Chapter 4.6 --- RESULTS --- p.106 / Chapter 4.6.1 --- Effects of ELP on bone mineral density (BMD) --- p.106 / Chapter 4.6.2 --- Effects of ELP on bone micro-architecture --- p.118 / Chapter 4.6.3 --- Effects of ELP on biomechanics of bone --- p.122 / Chapter 4.6.4 --- Effects of ELP on bone turnover --- p.125 / Chapter 4.7 --- DISCUSSION --- p.132 / Chapter CHAPTER 5: --- PART 3 IN VIVO STUDY ON BONE DEFECT HEALING --- p.140 / Chapter 5.1 --- HERBAL ITEMS SELECTED IN THIS PART --- p.140 / Chapter 5.2 --- DESIGN OF STUDY --- p.143 / Chapter 5.3 --- HYPOTHESES AND OBJECTIVES --- p.144 / Chapter 5.4 --- SPECIFIC STRATEGY ON PROMOTION OF FRACTURE HEALING OF TCM --- p.144 / Chapter 5.5 --- POTENTIAL EFFECT OF ELP ON BONE HEALING --- p.144 / Chapter 5.6 --- ANIMAL MODELS --- p.146 / Chapter 5.6.1 --- Bone fracture model --- p.147 / Chapter 5.6.2 --- Drill-hole bone defect model --- p.147 / Chapter 5.7 --- ASSESSMENTS ON BONE HEALING --- p.149 / Chapter 5.7.1 --- Micro-architecture analysis --- p.149 / Chapter 5.7.2 --- Bone strength assessment --- p.150 / Chapter 5.7.3 --- Bone turnover monitoring by measuring biochemical markers --- p.151 / Chapter 5.7.4 --- Histomorphometry --- p.151 / Chapter 5.8 --- MATERIALS AND METHODS --- p.153 / Chapter 5.8.1 --- Preparation of herbal extracts --- p.153 / Chapter 5.8.1.1 --- ELP --- p.153 / Chapter 5.8.1.2 --- CDNR --- p.153 / Chapter 5.8.2 --- Production of drill-hole bone defect --- p.154 / Chapter 5.8.2.1 --- Femur --- p.155 / Chapter 5.8.2.2 --- Tibia --- p.155 / Chapter 5.8.2.3 --- Animal arrangement and grouping --- p.157 / Chapter 5.8.3 --- Herbal formulae administration and application --- p.157 / Chapter 5.8.3.1 --- Oral administration --- p.157 / Chapter 5.8.3.2 --- Topical application --- p.157 / Chapter 5.8.4 --- Assessments on bone healing --- p.158 / Chapter 5.8.4.1 --- Bone micro-architecture and bone density measurement using in vivo micro-computed tomography (vivaCT) --- p.158 / Chapter 5.8.4.2 --- Bone strength assessment through biomechanical bending test --- p.159 / Chapter 5.8.4.3 --- Bone turnover monitoring by measuring biochemical markers --- p.160 / Chapter 5.8.4.4 --- Histomorphometry --- p.160 / Chapter 5.8.4.4.1 --- Fluorochrome double labeling --- p.160 / Chapter 5.8.4.4.2 --- Tissue processing and sectioning --- p.161 / Chapter 5.8.4.4.3 --- Staining of sections --- p.162 / Chapter 5.8.4.4.4 --- Image analysis --- p.164 / Chapter 5.8.5 --- Statistical analysis --- p.165 / Chapter 5.9 --- RESULTS --- p.166 / Chapter 5.9.1 --- Effect of ELP and CDNR on bone micro-architecture --- p.and / Chapter bone --- density at the bone defect site --- p.166 / Chapter 5.9.2 --- Histomorphometrical findings in treatment of bone healing --- p.172 / Chapter 5.9.3 --- Effect of ELP and CDNR on biomechanics of bone --- p.175 / Chapter 5.9.4 --- Effect of ELP and CDNR on bone turnover --- p.178 / Chapter 5.10 --- DISCUSSION --- p.184 / Chapter CHAPTER 6: --- GENERAL DISCUSSION AND CONCLUSION --- p.193 / Chapter 6.1 --- UNKNOWN AREAS FOR THE STUDY OF ELP --- p.193 / Chapter 6.2 --- SUMMARY OF CRUCIAL FINDINGS OF THE OSTEOGENIC EFFECTS OF ELP IN EACH PART OF THIS STUDY --- p.194 / Chapter 6.2.1 --- Part 1: in vitro seropharmacological study on osteoporosis --- p.194 / Chapter 6.2.2 --- Part 2: in vivo study on disuse osteoporosis --- p.195 / Chapter 6.2.3 --- Part 3: in vivo study on bone healing --- p.196 / Chapter 6.3 --- COMMON OSTEOGENIC EFFECT OF ELP IN THE THREE PARTS OF THE WHOLE STUDY --- p.197 / Chapter 6.4 --- LIMITATIONS OF THE PRESENT STUDY --- p.197 / Chapter 6.5 --- SIGNIFICANCES OF THIS STUDY --- p.199 / Chapter 6.6 --- FUTURE STUDIES --- p.199 / BIBLIOGRAPHY --- p.201

A direct bone tendon junction consists of four zones: tendon, uncalcified fibrocartilage, calcified fibrocartilage, and bone. The uncalcified and calcified fibrocartilage together forms the transition zone. This organization ensures a gradual transition in stiffness and material properties, and protects the junction from failure. Transition zone regeneration during bone tendon junction healing is important to restore this unique protective mechanism. / Bone tendon junction repair is involved in many orthopaedic reconstructive procedures. Healing is observed to be slow. The junction often heals by fibrous tissue formation. Previous attempts to enhance bone tendon junction healing have resulted in increased bone formation. However, fibrocartilage transition zone is not restored. / This thesis describes a series of studies on transition zone regeneration in bone tendon junction healing using two partial patellectomy animal models. The healing process inside a bone trough was first studied and characterized. Little transition zone regeneration was observed except near the articular cartilage cut surface. The possibility of using articular cartilage to stimulate transition zone regeneration was explored. Both articular cartilage autograft and allogeneic cultured chondrocyte pellet implantations resulted in significantly increased fibrocartilage transition zone regeneration. Cell tracking indicated that the regenerated tissue likely originated from host cells. To elucidate the mechanism of stimulation by allogeneic cultured chondrocyte pellet, the role of cellular and matrix component needed to be differentiated. Freezing and rapid freeze thaw cycles permanently devitalized the allogeneic cultured chondrocyte pellet, but retained its structural integrity and matrix contents. Preliminary results indicated that implantation of the devitalized allogeneic cultured chondrocyte pellet could still increase fibrocartilage transition zone regeneration. Cellular activity seemed not to be essential for the stimulatory effect. / With further research and development, it is envisioned that a cartilage-based stimulation method for fibrocartilage transition zone regeneration in bone tendon junction healing will be developed for clinical application. / Wong Wan Nar, Margaret. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3423. / Thesis (M.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 216-231). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Foi analisada a parte trabecular do colo do fêmur de 13 pacientes do sexo feminino, com idade acima dos 60 anos, com o método da histomorfometria óssea. Sete destas pacientes tiveram fratura do colo do fêmur. Todas foram submetidas a artroplastia do quadril. O exame de densitometria óssea não mostrou diferença significativa. Na espessura média das trabéculas não houve diferença significativa, porém o número de trabéculas foi menor e a separação entre elas foi maior no grupo com fraturas. / A histomorphometry evaluation of the trabecular part of the femoral neck was performed in 13 women over 60 years old submitted to hip arthroplasty. Seven of these patients had a femoral neck fracture. The bone mineral density showed no difference between both groups. The average thickness did not have significant between both groups, but the trabecular separation was higher and the number of trabecular bone was lower in the fracture group.

Thesis (Ph.D)--University of Tennessee Health Science Center, 2007. / Title from title page screen (viewed on October 8, 2007). Research advisor: Joo L. Ong, Ph.D. Document formatted into pages (xiii, 128 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 106-114).

Members of the Runx family of transcription factors play essential roles in the differentiation and development of several organ systems. Here we address the contribution of the osteoblast-related Runx gene, Runx2, to the osteogenic and chondrogenic differentiation of mesenchymal stem cells. Using a transgenic mouse model, we observe Runx2 transcription through one of its two known promoters (designated P1 in pre-cartilaginous mesenchymal condensations as early as E9.5. Runx2 gene activity is later repressed at the onset of cartilage formation, both in vivo and in vitro, necessitating examination of the regulation and function of Runx2 in mesenchymal stem cells. We demonstrate that Runx2 gene activity is repressed by the direct interaction of the homeodomain transcription factor Nkx3.2 with the proximal Runx2 P1 promoter. This repression was found to be required for the progression of BMP-induced chondrogenesis, thereby identifying Runx2 as a modulator of BMP activity in the chondrogenic as well as osteogenic differentiation program. To further understand the regulation of the Runx2 P1 promoter and to determine the contribution of P1-derived gene product, Runx2 Type II, to the formation of mineralized tissue, we have generated a Runx2 Type II-LacZ gene replacement mouse model in which the initial coding sequences and splice donor sites of the Type II isoform are replaced with the LacZ reporter gene. Activity of the endogenous P1 promoter can therefore be monitored by β-galactosidase production. Analysis of Runx2 Type II-LacZ mice demonstrates that the P1 promoter is transcriptionally most active in mature osteoblasts, but its product, Runx2 Type II is dispensable for embryonic skeletal formation. Lastly, we examine the link between growth control and osteogenic differentiation by tissue-specific deletion of the Mdm2 proto-oncogene in developing skeletal tissues of the mouse embryo. Loss of Mdm2 results in impaired bone formation, with skeletal elements exhibiting lower bone mineral content and higher porosity. Ex vivo cultures of calvarial osteoprogenitor cells exhibit severely decreased osteoblastogenesis and bone nodule formation accompanied by a failure to activate Runx2 gene activity. These findings suggest that Mdm2 is required for inhibition of p53 activity that ultimately allows for post-confluent proliferation and induction of Runx2 during maturation of the osteogenic phenotype. Taken together, our findings suggest that Runx2 modulates the commitment of progenitor cells to the osteogenic and chondrogenic lineages, and that Runx2 activity is inextricably linked to mechanisms that control cellular proliferation.

Made available in DSpace on 2014-06-11T19:31:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-17Bitstream added on 2014-06-13T18:41:42Z : No. of bitstreams: 1 almeidajunior_p_dr_araca.pdf: 1442119 bytes, checksum: ef1ca4851f34bc366b4409f8e330ec15 (MD5) / Proposição: O objetivo deste trabalho foi avaliar a influência de três meios de armazenamento temporário no processo de reparo de enxertos ósseos retirados de calota craniana e fixados em mandíbula de coelhos. Material e Método: Foram removidos dois blocos ósseos de 9mm da calota craniana de 40 coelhos machos e colocados no ângulo mandibular direito e esquerdo. O enxerto ósseo foi fixado ao leito receptor imediatamente após a sua remoção (G1), fixado 2 horas após armazenamento em meio seco (G2), 2 horas imerso em solução fisiológica (G3) e 2 horas imerso em solução de Euro Collins® (G4), todos a temperatura ambiente. Os animais foram sacrificados aos 7, 15, 30 e 60 dias pós-operatórios. Uma medida macroscópica padronizada da espessura do enxerto posicionado no leito receptor foi aferida no transoperatório e após o sacrifício de cada grupo. Os cortes histológicos foram corados pela hematoxilina e eosina e pela técnica de imunoistoquímica, através da expressão das proteínas osteocalcina (OC) e fosfatase ácida tartarato-resistente (TRAP). Resultado: A espessura do enxerto e rebordo evidenciou um comportamento uniforme entre os grupos, quando comparados no mesmo período, não havendo diferença estatisticamente significativa. A análise histométrica do percentual de osso neoformado na interface entre o leito receptor e o enxerto demonstrou não haver diferença estatística entre os grupos, no período de 7 e 15 dias pós-operatórios, exceto o grupo G1 que mostrou-se estatisticamente superior em relação ao grupo G4 (p=0,0227) aos 15 dias. Houve uma maior imunomarcação para TRAP e OC verificada no grupo G1, porém sem diferença significante entre os grupos do mesmo período. Conclusão: A solução fisiológica e de Euro Collins® utilizadas como meio de armazenamento temporário, demonstraram influenciar de forma semelhante na biocompatibilidade... / Purpose: The aim of this study was to evaluate the influence of three temporary storage environments in the repair process of bone grafts removed from the calvaria and fixed in rabbits’ mandible. Materials and Methods: Two bone blocks with 9 mm were removed from the calvaria of 40 male rabbits and placed on their right and left mandible angles. Bone graft was placed at the receptor site immediately after its removal (G1), placed 2 hours after storage in dry environment (G2), 2 hours immersed in physiological solution (G3) and 2 hours immersed in Euro Collins® solution (G4), all of them at room temperature. The animals were euthanized at 7, 15, 30 and 60 post-operative days. A standard macroscopic measurement of the graft thickness positioned at the receptor site was done at the trans-operative period and after the euthanasia of each group. Histological sections were stained by hematoxylin and eosin and by immunohistochemical technique, through the expression of the proteins osteocalcin (OC) and tartrate-resistant acid phosphatase (TRAP). Results: Ridge and graft thicknesses evidenced an uniform behavior among the groups, when the same periods were compared, and there was no statistically significant difference. Histometric analysis of the newly formed bone percentage at the interface between the receptor site and the graft showed no statistical difference among the groups in the post-operative periods of 7 and 15 days, except G1 group, which showed to be statistically higher when compared to G4 group (p=0,0227), at 15 days. There was a higher immunomarking for TRAP and OC, verified at G1 group, however without significant difference between the groups of the same period. Conclusion: Physiological and Euro Collins® solutions used as temporary storage environments showed to influence, similarly, the biocompatibility process of the autogenous bone graft, presenting a repair process dynamics close to immediate grafting procedure.

INTRODUÇÃO: A maioria dos estudos sobre baixa massa muscular e osso envolvem populações idosas. No entanto, como o hipoestrogenismo nos primeiros anos da menopausa é capaz de modular negativamente a massa óssea e muscular, é importante compreender a interação entre músculo e osso neste período. Além disso, há uma escassez de estudos que investigam a influência potencial da massa e função muscular sobre a qualidade óssea (microarquitetura e resistência), o que poderia fornecer uma visão mais abrangente do risco de fratura nesta população. O objetivo deste artigo foi avaliar as correlações potenciais entre parâmetros musculares (massa, força e função) e microarquitetura e resistência óssea utilizando a tomografia computadorizada periférica de alta resolução (HR-pQCT) em mulheres pós-menopáusicas. MÉTODOS: Um total de 225 mulheres menopausadas saudáveis (56,4 ± 4,6 anos) foram avaliadas por questionário clínico, exames laboratoriais e composição corporal (DXA, Hologic, QDR-4500). A qualidade dos ossos (densidade, microarquitetura, porosidade cortical e resistência) foi analisada por tomografia computadorizada periférica de alta resolução (rádio distal e tíbia, XtremeCT, Scanco Medical, Brüttisellen, Suíça). A mobilidade funcional e o desempenho muscular foram medidos pela força de preensão palmar (dinamômetro do modelo JAMAR), testes de levantar e sentar em 30 segundos e teste de levantar e caminhar cronometrado. O equilíbrio foi avaliado pela Escala de equilíbrio de Berg. A correlação entre parâmetros ósseos (HR-pQCT) e desempenho muscular foi analisada pelo teste de Spearman (p < 0,05). RESULTADOS: No rádio, houve correlações positivas entre a força de preensão palmar e os parâmetros do HR-pQCT do osso trabecular (densidade mineral óssea volumétrica trabecular [Tb.vBMD]: r = 0,17, p = 0,03, espessura trabecular [Tb.Th]: r = 0,16, p = 0,04), bem como entre a força muscular e a resistência óssea (Rigidez [S]: r = 0,36, p < 0,001). Na tíbia, a massa muscular da perna esquerda foi correlacionada positivamente com o número de trabéculas [Tb.N] (r = 0,16, p < 0,001), separação trabecular [Tb.Sp]: r = - 0,15, p = 0,02), espessura cortical [Ct.Th] (r = 0,21, p = 0,01) e resistência óssea [S] (r = 0,37, p < 0,001). Não houve correlações significativas entre os parâmetros de HR-pQCT e os testes funcionais dos membros inferiores, exceto entre o equilíbrio e a Tb.vBMD na tíbia (r = 0,13, p = 0,04). Houve uma correlação negativa entre a gordura corporal total e a função muscular (teste de levantar e sentar em 30 segundos: r = - 0,21, p < 0,001, escala de equilíbrio de Berg: r = -0,21, p < 0,001). CONCLUSÃO: nas mulheres, nos primeiros anos da menopausa, a força muscular parece desempenhar um papel mais importante nos parâmetros ósseos do membro superior (rádio), enquanto a massa muscular parece exercer maior influência no osso do membro inferior (tíbia). Esses achados sugerem uma diferença na relação entre músculo e osso de acordo com os diferentes segmentos do corpo. Além disso, a correlação negativa entre gordura corporal com função e equilíbrio muscular indica que o aumento da massa gorda corporal pode conferir maior risco de quedas nesta população. Estudos longitudinais são necessários para confirmar esses dados / INTRODUCTION: Most studies on low muscle mass and bone involve elderly populations. However, because postmenopausal hypoestrogenism is able to negatively modulate bone and muscle mass, it is important to understand the interplay between muscle and bone in early menopause. In addition, there is a paucity of studies investigating the potential influence of muscle mass and function upon bone quality (microarchitecture and strength), which could provide a more comprehensive view of fracture risk in this population. The aim of this article was to assess the potential correlations between muscle parameters (mass, strength and function), and bone microarchitecture and strength using high-resolution peripheral computed tomography (HR-pQCT) in postmenopausal women. METHODS: A total of 225 healthy menopausal women (aged 56.4 ± 4.6 years) were evaluated by clinical questionnaire, laboratory and body composition (DXA, Hologic, QDR-4500). Bone quality (density, microarchitecture, strength and cortical porosity) was analyzed by high resolution peripheral computed tomography (distal radius and tibia, XtremeCT, Scanco Medical, Brüttisellen, Switzerland). Functional mobility and muscle performance were measured by hand grip strength (JAMAR model dynamometer), Timed-Stand and Timed Up & Go tests. Balance was assessed by the Berg Balance Scale. The correlation between bone parameters (HR-pQCT) and muscle performance was analyzed by the Spearman test (p < 0.05). RESULTS: At the radius, there were positive correlations between hand grip strength and trabecular bone HR-pQCT parameters (trabecular volumetric bone mineral density [Tb.vBMD]: r=0.17, p = 0.03, trabecular thickness [Tb.Th]: r=0.16, p=0.04), as well as between muscle strength and bone strength (Stiffness [S]: r = 0.36, p < 0.001). At the tibia, the left leg muscle mass was positively correlated with number of trabeculae [Tb.N] (r = 0.16, p < 0.001), trabecular separation [Tb.Sp]: r=- 0.15, p= 0.02), cortical thickness [Ct.Th] (r = 0.21, p = 0.01) and bone strength [S] (r= 0.37, p < 0.001). There were no significant correlations between HR-pQCT parameters and lower limb functional tests, except between the balance and tibial Tb.vBMD (r= 0.13, p = 0.04). There was a negative correlation between total body fat and muscle function (30-s chair test: r = -0.21, p < 0.001, balance: r = -0.21, p < 0.001). CONCLUSION: In postmenopausal women, muscle strength seems to play a more important role in the upper limb bone (radius) parameters, whereas muscle mass seems to exert a higher influence on the lower limb bone (tibia). These findings suggest a difference on relationship between muscle and bone according to distinct body segments. In addition, the negative correlation between body fat and balance/muscle function indicate that increased body fat mass might confer increased risk of falls in this population. Longitudinal studies are needed to test these assumptions