Bone Morphological Parameters Research Articles

Effect of Morinda officinalis capsule on osteoporosis in ovariectomized rats

AimTo explore the therapeutic effects of Morinda officinalis capsules (MOP) on osteoporosis in ovariectomized rats. MethodsSix-month-old female Sprague–Dawley rats were induced for postmenopausal osteoporosis (PMOP) by bilateral ovariectomy and divided into seven groups as follows: sham-operated group, ovariectomized (OVX) control group, OVX treated with xianlinggubao (XLGB) (270 mg·kg−1·d−1), OVX treated with alendronate sodium (ALN) (3 mg·kg−1·d−1), and OVX treated with Morinda officinalis capsule (MOP) of graded doses (90, 270 and 810 mg·kg−1·d−1) groups. Oral treatments were administered daily on the 4th week after ovariectomy and lasted for 12 weeks. The bone mineral density was evaluated by dual-energy X-ray absorptiometry. The tartrate-resistant acid phosphatase (TRAP), alkaline phosphatase (AKP), and osteocalcin (OC) levels in the serum and plasma were determined by standard colorimetric and enzyme immunoassays methods. Bone biomechanical properties and morphological parameters were analyzed by three-point bending test and histomorphometry respectively. ResultsMorinda officinalis capsules at all doses were able to significantly prevent the OVX-induced loss of bone mass due to diminishing serum AKP and TRAP levels while elevating OC level in the plasma. Morinda officinalis capsules also enhanced the bone strength and prevented the deterioration of trabecular microarchitecture. ConclusionMorinda officinalis capsules possess potent anti-osteoporotic activity in OVX rats which could be an effective treatment for postmenopausal osteoporosis.

Inter-individual variability of bone density and morphology distribution in the proximal femur and T12 vertebra

Bone geometry, density and microstructure can vary widely between subjects. Knowledge about this variation in a population is of interest in particular for the design of orthopedic implants and interventions. The goal of this study is to investigate the local variability of bone density and microstructural parameters between subjects using a novel inter-subject image registration approach. Human proximal femora of 29 and T12 vertebrae of 20 individuals were scanned using a HR-pQCT and a micro-CT system, respectively. A pre-defined iso-anatomic mesh template was morphed to each micro-CT scan. For each element bone volume fraction and other morphological parameters (Tb.Th, Tb.N, Tb.Sp, SMI, DA) were determined and assigned to the element. A coefficient of variation (CV) was calculated for each parameter at each element location of the 29 femora and 20 T12 vertebrae. Contour plots of the CV distribution revealed very detailed information about the inter-individual variation in bone density and morphology. It is also shown that analyzing large sub-volumes, as commonly done in previous studies, would miss much of this variation. Detailed quantitative information of bone morphological parameters for each sample in the femur and the T12 database and their inter-individual variability are available from the mesh templates as supplementary data (http://w3.bmt.tue.nl/nl/fe_database/). We expect that these results can help to optimize implants and orthopedic procedures by taking local bone morphological parameter variations into account.

Efficacy and safety of lanthanum carbonate on chronic kidney disease-mineral and bone disorder in dialysis patients: a systematic review.

BackgroundChronic kidney disease–mineral and bone disorder (CKD–MBD) is a common complication in CKD patients, particularly in those with end-stage renal disease that requires dialysis. Lanthanum carbonate (LC) is a potent, non-aluminum, non-calcium phosphate binder. This systematic review evaluates the efficacy and safety of LC in CKD-MBD treatment for maintenance-dialysis patients.MethodsA systematic review and meta-analysis on randomized controlled trials (RCTs) and quasi-RCTs was performed to assess the efficacy and safety of LC in maintenance hemodialysis or peritoneal dialysis patients. Analysis was performed using the statistical software Review Manager 5.1.ResultsSixteen RCTs involving 3789 patients were identified and retained for this review. No statistical difference was found in all-cause mortality. The limited number of trials was insufficient to show the superiority of LC over other treatments in lowering vascular calcification or cardiovascular events and in improving bone morphology, bone metabolism, or bone turn-over parameters. LC decreased the serum phosphorus level and calcium × phosphate product (Ca × P) as compared to placebo. LC, calcium carbonate (CC), and sevelamer hydrochloride (SH) were comparable in terms of controlling the serum phosphorus, Ca × P product, and intact parathyroid hormone (iPTH) levels. However, LC resulted in a lower serum calcium level and a higher bone-specific alkaline phosphatase level compared with CC. LC had higher total cholesterol and low-density lipoprotein (LDL) cholesterol levels compared with SH. LC-treated patients appeared to have a higher rate of vomiting and lower risk of hypercalcemia, diarrhea, intradialytic hypotension, cramps or myalgia, and abdominal pain. Meta-analysis showed no significant difference in the incidence of other side effects. Accumulation of LC in blood and bone was below toxic levels.ConclusionsLC has high efficacy in lowering serum phosphorus and iPTH levels without increasing the serum calcium. Current evidence does not show a higher rate of adverse effects for LC compared with other treatments, except for a higher incidence of vomiting. Moreover, LC accumulation in blood and bone was below toxic levels. Well-designed studies should be conducted to evaluate the long-term effects of LC.

Extracellular matrix-coating pedicle screws conduct and induce osteogenesis

The purpose of the present study was to study the effects of the extracellular matrix-coating pedicle screws on the conduction and induction of bone formation in young sheep. Pedicle screws [coated with collagen/chondroitin sulfate (coll/CS), hydroxyapatite (HA), and coll/CS/HA or uncoated] were randomly implanted into the L2-L5 pedicles of sheep. In the first stage, a static experiment was performed. In the second stage, a loading test was performed by implanting connecting rods. After 3months, the lumbar vertebrae with the screws were removed and examined by micro-CT, histological, and biomechanical analyses. Under non-loading conditions, there is bone formation around the surfaces of coated screws. Bone formation on the surface of the coll/CS/HA coating of pedicle screws was the highest. In terms of the trabecular bone morphology parameters of the region of interest around the surface of the pedicle screws, those associated with coll/CS/HA coatings were highest under non-loading conditions, the pullout strength of the coll-/CS-/HA-coated screws was the highest and that of the uncoated screws was minimal. Under loading conditions, the maximum pullout strength of each group of pedicle screws was less than that of the pedicle screws in the non-loading state. Under non-loading conditions, the organic and inorganic components of the titanium pedicle screw coatings can conduct or induce bone formation around the surface of the screws. The ability of the coll/CS/HA coating to induce bone formation was the strongest. Under loading conditions, a large amount of connective tissue formed around the surface of the screws in each group.

Gender-Dependence of Bone Structure and Properties in Adult Osteogenesis Imperfecta Murine Model

Osteogenesis imperfecta (OI) is a dominant skeletal disorder characterized by bone fragility and deformities. Though the oim mouse model has been the most widely studied of the OI models, it has only recently been suggested to exhibit gender-dependent differences in bone mineralization. To characterize the impact of gender on the morphometry/ultra-structure, mechanical properties, and biochemical composition of oim bone on the congenic C57BL/J6 background, 4-month-old oim/oim, +/oim, and wild-type (wt) female and male tibiae were evaluated using micro-computed tomography, three-point bending, and Raman spectroscopy. Dramatic gender differences were evident in both cortical and trabecular bone morphological and geometric parameters. Male mice had inherently more bone and increased moment of inertia than genotype-matched female counterparts with corresponding increases in bone biomechanical strength. The primary influence of gender was structure/geometry in bone growth and mechanical properties, whereas the mineral/matrix composition and hydroxyproline content of bone were influenced primarily by the oim collagen mutation. This study provides evidence of the importance of gender in the evaluation and interpretation of potential therapeutic strategies when using mouse models of OI.

Synergistic effect of scaffold composition and dynamic culturing environment in multilayered systems for bone tissue engineering

Bone extracellular matrix (ECM) is composed of mineralized collagen fibrils which support biological apatite nucleation that participates in bone outstanding properties. Understanding and mimicking bone morphological and physiological parameters at a biological scale is a major challenge in tissue engineering scaffolding. Using emergent (nano)technologies scaffold designing may be critically improved, enabling highly functional tissue substitutes for bone applications. This study aims to develop novel biodegradable composite scaffolds of tricalcium phosphate (TCPs) and electrospun nanofibers of poly(ϵ-caprolactone) (PCL), combining TCPs osteoconductivity with PCL biocompatibility and elasticity, mimicking bone structure and composition. We hypothesized that scaffolds with such structure/composition would stimulate the proliferation and differentiation of bone marrow stromal cells (BMSCs) towards the osteogenic phenotype. Composite scaffolds, developed by electrospining using consecutive stacked layers of PCL and TCPs, were characterized by FTIR spectroscopy, X-Ray diffraction and scanning electronic microscopy. Cellular behavior was assessed in goat BMSCs seeded onto composite scaffolds and cultured in static or dynamic conditions, using basal or osteogenic media during 7, 14 or 21 days. Cellular proliferation was quantified and osteogenic differentiation confirmed by alkaline phosphatase activity, alizarin red staining and immunocytochemistry for osteocalcin and collagen I. Results suggest that PCL-TCP scaffolds provide a 3D support for gBMSCs proliferation and osteogenic differentiation with production of ECM. TCPs positively stimulate the osteogenic process, especially under dynamic conditions, where PCL-TCP scaffolds are sufficient to promote osteogenic differentiation even in basal medium conditions. The enhancement of the osteogenic potential in dynamic conditions evidences the synergistic effect of scaffold composition and dynamic stimulation in gBMSCs osteogenic differentiation.

The effect of maximum bite force on alveolar bone morphology

To investigate to what extent maximum bite force contributes to alveolar bone morphology parameters, i.e. alveolar thickness, shape and arch width. An observational cross-sectional survey. One hundred and fifty one 12- to 14-year-old students from a secondary school in Hatyai City, Songkhla Province, Thailand. Height, weight and maximum bite force of each subject were recorded. Alveolar bone morphology parameters were measured from study models. Maximum bite force moderately correlated with alveolar thickness and shape (r = 0.31-0.44, p < 0.001), but weakly correlated with arch width (r = 0.03-0.05, p > 0.05). After adjusting for gender and body mass index (BMI), the maximum bite force significantly determined alveolar thickness and shape (p < 0.001), accounting for 10-20% of the variations. Boys were associated with larger posterior arch width (p < 0.01), where BMI was not associated with alveolar bone morphology parameters (p > 0.01) after Bonferroni correction for multiple testing. Maximum bite force had a selective influence on alveolar thickness and shape, but not on arch width.

BONE TISSUE ENGINEERING: EFFECT OF COMPRESSION ON GROWTH PATTERNS REVEALED BY μCT MONITORING

Custom-made culture chambers were kept inside an incubator. For mechanical compression the chambers were taken out of the incubator and mounted into a custom-made mechanical stimulation unit. For time-lapsed in situ imaging the culture chambers were placed inside a μCT desktop system under sterile conditions. In this way, bone morphological parameters of individual constructs could be monitored throughout the culture period. Each culture chamber (n=3) hosted one loaded sample and one non-loaded control sample, which were exposed to the same environment except for the mechanical stimulation. Human mesenchymal stem cells were cultured on silk fibroin scaffolds in osteogenic medium (7mM -GP, 50μg/ml ascorbic acid, 10nM Dexamethasone, 1μg/ml BMP-2) for 42 days in the system. The samples in the loaded group were compressed by 5% of their height. Loading frequencies were 10 Hz from days 14-24 and 6 Hz from days 25-42.

Warfarin-induced impairment of cortical bone material quality and compensatory adaptation of cortical bone structure to mechanical stimuli

Long-term warfarin use has been reported to increase fracture risk of rib and vertebra but not hip in elderly patients, but the mechanisms remain unknown. We hypothesized that warfarin would impair bone material quality but could not weaken bone strength under conditions with higher mechanical stimuli. To test this hypothesis, rats were randomized to vehicle or warfarin group at 4 weeks of age and subsequently weight matched into a sedentary or jumping exercise group at 12 weeks of age. At 6 months of age, osteocalcin content, bone mineral density (BMD), mineral size, material properties, morphological parameters, and biomechanical properties of cortical bones were evaluated. In order to seek evidence for a common mechanism of action, effects of nucleation rate of mineral crystals on their rigidity were also investigated using computer simulation. In humeral cortical bones, warfarin did not change BMD, but markedly decreased osteocalcin content, diminished mineral size, and impaired material hardness. Consistent with these results, our computer-simulation model showed that osteocalcin-induced delay of mineral crystal nucleation decreased mineral formation rate, increased mean and distribution of mineral sizes, and strengthened mineral rigidity. In tibial cortical bones, warfarin decreased material ultimate stress; however, under jumping exercise, warfarin increased cross-sectional total and bone areas of these tibiae and completely maintained their biomechanical properties including work to failure. Collectively, our findings suggest that long-term warfarin therapy weakens rib and vertebra by impairing cortical bone material quality due to a marked decrease in osteocalcin content but could not reduce hip strength through compensatory adaptation of cortical bone structure to higher mechanical stimuli.

Influence of Short‐term Confinement and Exercise on Tibia Development in Growing Pigs

The influence of short-term confinement and moderate exercise on tibia development was investigated in growing pigs (36-41 kg, 10 weeks at the beginning of the study). Animals were kept for 2 weeks either in individual crates of 0.8 m(2) ('confinement', n = 4) or kept in groups of four animals in large crates of 5.6 m(2) without ('control') or with additional exercise (30 min walking at 5 days/week; 'exercise'). Bone density and morphological parameters were evaluated by computer tomography (CT). Periosteal apposition and longitudinal growth were determined after polychrome sequential labelling in weekly intervals. Cortical areas of the cross sections at the mid-shaft and at 75% of the length of the bone measured distal to the carpus by CT were significantly correlated to each other (r = 0.70) and revealed a significant reduction in confined animals. This difference was explained by lower periosteal apposition rates in these animals compared with exercised and group-housed pigs. Similarly longitudinal growth and the formation and calcification of spongiosa of the tibiae were inhibited by confinement. Thus, 2 weeks of confinement led to significant differences in bone growth and metabolism in young growing piglets when compared with animals with moderate activity.

Subchondral bone micro-architectural alterations in osteoarthritis: a synchrotron micro-computed tomography study

We evaluated the three-dimensional (3D) micro-architecture of subchondral trabecular (Tb) bone in osteoarthritis (OA). Due to high signal-to-noise ratio and high resolution, micro-computed tomography (micro-CT) by synchrotron radiation is considered as the gold standard for bone micro-architecture imaging. Subchondral bone were extracted from femoral heads in OA cases in areas without cartilage (OAc-; n=6) and in adjacent areas with cartilage (OAc+; n=6) and compared to eight subchondral bone cores from osteoporosis cases (OP). The voxel size of images was 10.13 microm. We measured the bone volume fraction (BV/TV) and morphological parameters: Tb thickness (TbTh), Tb spacing (TbSp), Tb number (TbN), and bone surface/bone volume (BS/BV). The degree of anisotropy (DA), the connectivity by the Euler number and the degree of mineralization (DM) were equally assessed. BV/TV and morphological parameters showed significant differences between OAc- and OP samples (P<0.01 except TbTh: P<0.05) and between OAc- and OAc+ (0.05<P<0.01) but no difference between OAc+ and OP except TbN (P<0.01). The connectivity was higher in OAc- comparatively to OAc+ and OP. The DA were significantly different between OA and OP cases (P<0.01) but not between OAc- and OAc+ specimens. The DMs (mean+/-SD) were 0.817+/-0.142 g/cm(3), 0.873+/-0.161 g/cm(3), 0.906+/-0.156 g/cm(3) for OAc-, OAc+, OP (P<0.01), respectively. Subchondral bone changes were mainly observed in advanced OA, when cartilage has been deleted and preserved in adjacent area. These data suggest that subchondral bone changes would be rather secondary to the cartilage deterioration than a primitive mechanism of OA. Nevertheless, longitudinal data could bring more accurate conclusions.

Modeling Deformation-Induced Fluid Flow in Cortical Bone?s Canalicular?Lacunar System

To explore the potential role that load-induced fluid flow plays as a mechano-transduction mechanism in bone adaptation, a lacunar-canalicular scale bone poroelasticity model is developed and implemented. The model uses micromechanics to homogenize the pericanalicular bone matrix, a system of straight circular cylinders in the bone matrix through which bone fluids can flow, as a locally anisotropic poroelastic medium. In this work, a simplified two-dimensional model of a periodic array of lacunae and their surrounding systems of canaliculi is used to quantify local fluid flow characteristics in the vicinity of a single lacuna. When the cortical bone model is loaded, microscale stress, and strain concentrations occur in the vicinity of individual lacunae and give rise to microscale spatial variations in the pore fluid pressure field. Furthermore, loading of the bone matrix containing canaliculi generates fluid pressures in the contained fluids. Consequently, loading of cortical bone induces fluid flow in the canaliculi and exchange of fluid between canaliculi and lacunae. For realistic bone morphology parameters, and a range of loading frequencies, fluid pressures and fluid-solid drag forces in the canalicular bone are computed and the associated energy dissipation in the models compared to that measured in physical in vitro experiments on human cortical bone. The proposed model indicates that deformation-induced fluid pressures in the lacunar-canalicular system have relaxation times on the order of milliseconds as opposed to the much shorter times (hundredths of milliseconds) associated with deformation-induced pressures in the Haversian system.

Five jumps per day increase bone mass and breaking force in rats.

The effects of jump training on bone morphological and mechanical properties were investigated in immature bones of female Fischer 344 rats. Five-week-old rats were divided into control or five jump-trained groups comprised of 5-, 10-, 20-, 40-, and 100-jump groups, representing the number of jumps per day. The rats were jump-trained 5 days/week for 8 weeks, and the height of jump was increased to 40 cm progressively. The femur and tibia in the 5-jump group had significantly greater fat-free dry weights per body weight and maximum loads at the fracture tests than those in the control group. The tibia in the 5-jump group also had significantly larger cortical area at the cross-sectional analysis. Although a slight tendency toward increase according to the number of jumps per day was observed, there were few differences in bone morphological and mechanical parameters among the 10-, 20-, and 40-jump groups. The present results indicate that a large number of strains per day is not necessary for bone hypertrophy to develop in rats.

骨粗しょう症の進行に関する理論的解析

Osteoporosis is a disease caused by an abnormal bone metabolism. In this paper, it was attempted to explain the progressive rate of osteoporosis based on the product of bone remodeling activity and morphological parameters of the trabecular structure of the cancellous bone. The main results obtained were as follows.As the bone formation became slow, the bone volume gradually decreased and the cortical bone was thinned. Furthermore, the porosity of the cancellous bone increased abnormally. These changes greatly impaired the mechanical properties of the bones. These abnormalities may also cause such a bone fracture as intracapsular femoral neck fracture.The value Vf obtained by the equation (13) is considered to represent the progressing behavior of osteoporosis at the proximal end of the femur.From the measurment of the metabolic activity and quantification of the morphological properties of cancellous bone structure, it was concluded that the highest progressive rate of resorption appeared in bar/bar like trabecular structure. The plate/bar like structure was the next and the plate/plate like structure was most insensitive.

Studies of Bone Morphology, Bone Densitometry and Laboratory Data in Patients on Maintenance Hemodialysis Treatment

Bone morphological parameters of renal osteodystrophy such as abundance of osteoid surface, osteoid seam width index, calcification fronts, osteoclast activity and trabecular bone volume were studied in 71 patients on maintenance hemodialysis and compared with bone densitometry, laboratory and clinical data. Increased osteoclast activity (hyperparathyroidism) was by far the most common bone morphological finding. Patients with chronic pyelonephritis or polycystic kidney disease had more than double the amount of osteoid than patients with chronic glomerulonephritis. The trabecular bone volume seemed to be increased in most patients in contrast to the cortical bone volume which was decreased, judged from bone densitometry and previously from X-ray. Despite that patients with polycystic kidney disease were older, their trabecular volume was larger than in patients with glomerulonephritis. The bone mineral content evaluated by bone densitometry was low in most patients, and more associated with bone morphological signs of osteomalacia than with secondary hyperparathyroidism. Serum phosphate (S-PO4) and serum parathyroid hormone (S-PTH) seemed to discriminate better between osteomalacia and secondary hyperparathyroidism than serum alkaline phosphatase (S-Alk. phosph.), which was elevated in both groups. Patients who had been bilaterally nephrectomized were no more abnormal than other patients, and they had lower S-Alk. phosph. The abundance of osteoclasts was found to be a predictor of future development of clinical secondary hyperparathyroidism.