Icariin Alleviates Glucocorticoid-Induced Osteoporosis through EphB4/Ephrin-B2 Axis

Purpose. Glucocorticoid (GC) is the most important risk factor for osteoporosis (OP); in the present study, we examined the potential mechanism of icariin, a natural bioactive compound isolated from the traditional Chinese herbal Epimedium, for GC-induced OP to explore its potential therapeutic effect. Methods. We used a GC-induced OP mice model and treated with icariin. Pathological changes were measured by H&E staining, and the effects of icariin on osteoblasts and osteoclasts were measured by immunohistochemistry (IHC) staining and western blot (WB) analyses, while trabecular bone parameters were detected by micro-CT imaging in vivo. Results. The results showed that in GC-induced OP symptoms, icariin treatment significantly increased the density of the trabecular bone when exposed to GC, revealed by H&E staining and micro-CT imaging. IHC staining showed that GC-induced OP had a lower EphB4 expression and higher Ephrin-B2 expression, but icariin could promote EphB4 while suppressing Ephrin-B2 expression. The WB results also provided evidence of the same protein expression trend, showing that the osteoblast marker OCN and the EphB4 downstream factor RhoA in the GC group were decreased, while both OCN and RhoA expression were significantly increased and the Ephrin-B2 downstream factor Grb4 in in GC group was increased after icariin treatment. Conclusion. Icariin could improve the characteristics of OP through regulating the balance of the EphB4/Ephrin-B2 pathway. Further preclinical trial is needed to provide certainty of clinical benefits for OP patients.

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Validation of an In Vivo Model for Monitoring Trabecular Bone Quality Changes Using Micro CT, Archimedes-based Volume Fraction Measurement and Serial Milling

IFMBE Proceedings - 13th International Conference on Biomedical Engineering ◽

10.1007/978-3-540-92841-6_138 ◽

2009 ◽

pp. 563-565

Author(s):

B. H. Kam ◽

M. J. Voor ◽

S. Yang ◽

R. Burden ◽

S. Waddell

Keyword(s):

Trabecular Bone ◽

Bone Quality ◽

Volume Fraction ◽

In Vivo Model ◽

Quality Changes ◽

Micro Ct ◽

Fraction Measurement ◽

Trabecular Bone Quality

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Radiosensitization and Micro CT Imaging of Multifunctional Gold Nanoparticles in Lung Adenocarcinoma A549 Cell: An In Vivo Animal Study

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2018.07.691 ◽

2018 ◽

Vol 102 (3) ◽

pp. e191 ◽

Cited By ~ 1

Author(s):

T. Li ◽

C. Yang ◽

G. Zhang ◽

J. Huang ◽

J. Lyu ◽

...

Keyword(s):

Gold Nanoparticles ◽

Lung Adenocarcinoma ◽

Animal Study ◽

A549 Cell ◽

Ct Imaging ◽

Micro Ct ◽

Lung Adenocarcinoma A549

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Effects of long-term in vivo micro-CT imaging on hallmarks of osteopenia and frailty in aging mice

PLoS ONE ◽

10.1371/journal.pone.0239534 ◽

2020 ◽

Vol 15 (9) ◽

pp. e0239534

Author(s):

Ariane C. Scheuren ◽

Gisela A. Kuhn ◽

Ralph Müller

Keyword(s):

Ct Imaging ◽

Micro Ct

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Segmentation of Trabecular Bone for In Vivo CT Imaging Using a Novel Approach of Computing Spatial Variation in Bone and Marrow Intensities

Computer Vision – ACCV 2016 Workshops - Lecture Notes in Computer Science ◽

10.1007/978-3-319-54526-4_1 ◽

2017 ◽

pp. 3-15

Author(s):

Cheng Chen ◽

Dakai Jin ◽

Xiaoliu Zhang ◽

Steven M. Levy ◽

Punam K. Saha

Keyword(s):

Spatial Variation ◽

Trabecular Bone ◽

Ct Imaging ◽

Novel Approach

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Preparation of On-Axis Cylindrical Trabecular Bone Specimens Using Micro-CT Imaging

Journal of Biomechanical Engineering ◽

10.1115/1.1645866 ◽

2004 ◽

Vol 126 (1) ◽

pp. 122-125 ◽

Cited By ~ 23

Author(s):

Xiang Wang, ◽

Xiangyi Liu, and ◽

Glen L. Niebur

Keyword(s):

Finite Element ◽

High Resolution ◽

Coordinate System ◽

Trabecular Bone ◽

Cylindrical Specimen ◽

Longitudinal Axis ◽

Ct Imaging ◽

Finite Element Models ◽

Micro Ct ◽

Average Deviation

The Orientation of trabecular bone specimens for mechanical testing must be carefully controlled. A method for accurately preparing on-axis cylindrical specimens using high-resolution micro-CT imaging was developed. Sixteen cylindrical specimens were prepared from eight bovine tibiae. High-resolution finite element models were generated from micro-CT images of parallelepipeds and used to determine the principal material coordinate system of each parallelepiped. A cylindrical specimen was then machined with a diamond coring bit. The resulting specimens were scanned again to evaluate the orientation. The average deviation between the principal fabric orientation and the longitudinal axis of the cylindrical specimen was only 4.70±3.11°.

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High-Resolution Three-Dimensional-pQCT Images Can Be an Adequate Basis for In-Vivo μFE Analysis of Bone

Journal of Biomechanical Engineering ◽

10.1115/1.1352734 ◽

2000 ◽

Vol 123 (2) ◽

pp. 176-183 ◽

Cited By ~ 74

Author(s):

W. Pistoia ◽

B. van Rietbergen ◽

A. Laib ◽

P. Ru¨egsegger

Keyword(s):

High Resolution ◽

Trabecular Bone ◽

Elastic Properties ◽

Bone Structure ◽

Reference Model ◽

Von Mises Stress ◽

Micro Ct ◽

Von Mises

Micro-finite element (μFE) models based on high-resolution images have enabled the calculation of elastic properties of trabecular bone in vitro. Recently, techniques have been developed to image trabecular bone structure in vivo, albeit at a lesser resolution. The present work studies the usefulness of such in-vivo images for μFE analyses, by comparing their μFE results to those of models based on high-resolution micro-CT (μCT) images. Fifteen specimens obtained from human femoral heads were imaged first with a 3D-pQCT scanner at 165 μm resolution and a second time with a μCT scanner at 56 μm resolution. A third set of images with a resolution of 165 μm was created by downscaling the μCT measurements. The μFE models were created directly from these images. Orthotropic elastic properties and the average tissue von Mises stress of the specimens were calculated from six FE-analyses per specimen. The results of the 165 μm models were compared to those of the 56 μm model, which was taken as the reference model. The results calculated from the pQCT-based models, correlated excellent with those calculated from the reference model for both moduli R2>0.95 and for the average tissue von Mises stress R2>0.83. Results calculated from the downscaled micro-CT models correlated even better with those of the reference models (R2>0.99 for the moduli and R2>0.96 for the average von Mises stress). In the case of the 3D-pQCT based models, however, the slopes of the regression lines were less than one and had to be corrected. The prediction of the Poisson’s ratios was less accurate (R2>0.45 and R2>0.67) for the models based on 3D-pQCT and downscaled μCT images respectively). The fact that the results from the downscaled and original μCT images were nearly identical indicates that the need for a correction in the case of the 3D-pQCT measurements was not due to the voxel size of the images but due to a higher noise level and a lower contrast in these images, in combination with the application of a filtering procedure at 165 micron images. In summary: the results of μFE models based on in-vivo images of the 3D-pQCT can closely resemble those obtained from μFE models based on higher resolution μCT system.

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Characterization of Rotating Gantry Micro-CT Configuration for theIn VivoEvaluation of Murine Trabecular Bone

Microscopy and Microanalysis ◽

10.1017/s1431927613001396 ◽

2013 ◽

Vol 19 (4) ◽

pp. 907-913 ◽

Cited By ~ 3

Author(s):

Luke Arentsen ◽

Susanta Hui

Keyword(s):

Trabecular Bone ◽

Signal To Noise Ratio ◽

Hounsfield Unit ◽

Rate Of Change ◽

Physical Parameters ◽

Micro Ct ◽

Detector Geometry ◽

Ct System ◽

Filter Thickness

AbstractThe objective of this study is to determine the optimal physical parameters of a rotating gantry micro-CT system to assessin vivochanges to the trabecular bone of mice. Magnification, binning, peak kilovoltage, beam filtration, and tissue thickness are examined on a commercially available micro-CT system. The X-ray source and detector geometry provides 1.3×, 1.8×, or 3.3× magnification. Binning is examined from no binning to 2 to 4. Energy is varied from 40 to 80 kVp in 10 kVp increments and filter thickness is increased from no filtration to 1.5 mmAl in 0.5 mmAl increments. Mice are imaged at different magnifications and binning combinations to evaluate changes to image quality and microstructure estimation. Increasing magnification from 1.3× to 3.3× and lowering binning from 4 to 1 varies the spatial resolution from 2.5 to 11.8 lp/mm. Increasing the beam energy or filtration thickness decreases Hounsfield unit (HU) estimation, with a maximum rate of change being −286 HU/kVp for 80 kVp. Images for murine trabecular bone are blurred at effective pixel sizes above 60 μm. By comparing resolution, signal-to-noise ratio, and radiation dose, we find that a 3.3× magnification, binning of 2.80 kVp beam with a 0.5 mmAl filter comprises the optimal parameters to evaluate murine trabecular bone for this rotating gantry micro-CT.

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