Histomorphometric Data Research Articles

Investigation of biomechanical response of Hoffa's fat pad and comparative characterization

The infrapatellar adipose body (Hoffa's fat pad, IFP) is situated between the patellar tendon, the femoral condyle and the tibial plateau. The IFP consists of lobules of white adipose tissue delimited by thin connective septa. The actual structural functionality of the IFP is debated and should pertain to a cushioning role in the knee joint, providing to distribute and to damp mechanical stresses during articular activity. The present study is aimed to analyze the correlation between histological configuration and mechanical properties of the IFP, compared to other adipose tissues, partially differentiated by composition and conformation. Histological and ultrastructural methods were exploited to analyze the microscopic anatomies of IFP, knee (KSF) and abdominal (ASF) subcutaneous fat tissues. Numerical micro-models of the different tissues were developed by using histo-morphometric data, as the size of adipose lobules, the thickness of the septa and their composition. Numerical analyses made it possible to evaluate the mechanical functionality of the different fat tissues considering the characteristic loading conditions, as compressive and shear actions. The results pointed out the actual mechanical relevance of IFP and KSF, while ASF exhibited different mechanical properties. Furthermore, the contribution of connective septa and adipose lobules to compressive and shear mechanical behavior was elucidated. This preliminary investigation represents the basis for biomechanical interpretation and the definition of more refined model to be developed on the acquisition of additional histological and morphometric data.

Accelerated craniofacial bone regeneration through dense collagen gel scaffolds seeded with dental pulp stem cells.

Therapies using mesenchymal stem cell (MSC) seeded scaffolds may be applicable to various fields of regenerative medicine, including craniomaxillofacial surgery. Plastic compression of collagen scaffolds seeded with MSC has been shown to enhance the osteogenic differentiation of MSC as it increases the collagen fibrillary density. The aim of the present study was to evaluate the osteogenic effects of dense collagen gel scaffolds seeded with mesenchymal dental pulp stem cells (DPSC) on bone regeneration in a rat critical-size calvarial defect model. Two symmetrical full-thickness defects were created (5 mm diameter) and filled with either a rat DPSC-containing dense collagen gel scaffold (n = 15), or an acellular scaffold (n = 15). Animals were imaged in vivo by microcomputer tomography (Micro-CT) once a week during 5 weeks, whereas some animals were sacrificed each week for histology and histomorphometry analysis. Bone mineral density and bone micro-architectural parameters were significantly increased when DPSC-seeded scaffolds were used. Histological and histomorphometrical data also revealed significant increases in fibrous connective and mineralized tissue volume when DPSC-seeded scaffolds were used, associated with expression of type I collagen, osteoblast-associated alkaline phosphatase and osteoclastic-related tartrate-resistant acid phosphatase. Results demonstrate the potential of DPSC-loaded-dense collagen gel scaffolds to benefit of bone healing process.

Low-residue diet fed to rabbits induces histomorphological and biomechanical remodeling of small intestine.

The composition of ingested food is important for the gut microbiome and intestinal homeostasis. We have previously demonstrated that the structure and mechanical properties in the small intestine remodel significantly during fasting. However, it is not clear to what extent the intestinal mechanical properties changes when the composition of food is changed. This study aimed to investigate the passive biomechanical properties and intestinal tissue remodeling in rabbits fed a low-residue diet. New Zealand rabbits (control group n=6, intervention group n=7) were studied. Segments from duodenum, jejunum and ileum were excised. The intestinal diameter and length were obtained from digitized images of the segments at preselected luminal pressure levels and at no-load and zero-stress states. Circumferential and longitudinal stresses (force per area) and strains (deformation) were computed from the length, diameter and pressure data referenced to the zero-stress state geometry. Histomorphometric data were also obtained. The wet weight-per-unit length, wall thickness and wall area decreased in the intervention group (P<.05, P<.01). Histological measurement confirmed that the wall thickness decreased in all three segments, which was primarily due to mucosal thinning (P<.05). The opening angle tended to increase in all segments in the intervention group. Significant difference between the two groups was found for the jejunum (P<.05). Feeding the low-residue diet shifted the circumferential stress-strain curves in the intervention group to the right, indicating intestinal wall softening. Low-residue diet in rabbits for 1month induces location-dependent histomorphometric and biomechanical remodeling of the intestine.

Use of Buccal Fat Pad for Closure of Perforation and Graft Material in a Maxillary Sinus Elevation Procedure: A Preliminary Study.

Maxillary sinus membrane elevation is a common procedure intended to increase the volume of the maxillary sinus osseous floor prior to insertion of dental implants. The aim of this study was to evaluate bone formation under a perforated sinus membrane grafted with buccal fat pad (BFP). Six consecutive patients (10 sinus augmentations, 24 dental implants) underwent sinus floor elevation, using the lateral window approach. The compartment around the implants under the sinus mucosal lining in the sinus floor was filled with adipose tissues, which were retrieved as free graft from BFP. Clinical and radiologic follow-up was conducted through the healing period; in all cases, samples were taken for biopsy during the stage-two surgery. New bone consolidation in the maxillary sinus was radiologically and histologically observed within an average of 7.2 months after the sinus augmentation. According to the histomorphometric data, 62.8% ± 13.1% vital bone formation was observed. Out of the 24 implants placed, only 1 failed, indicating a 95% overall implant survival rate. Despite the limited size of this case series, BFP can be considered an autologous osteogenic graft material and/or biologic membrane capable of achieving high success rates in sinus elevation procedures.

Graftless sinus augmentation with simultaneous dental implant placement: clinical results and biological perspectives

After a sinus lifting procedure, the compartment around the implants under the sinus mucosal lining in the sinus floor is filled with a blood clot from surrounding bleeding. The aim of this study was to evaluate the feasibility of bone formation following graftless sinus lifting with the simultaneous placement of dental implants. Thirty graftless sinus lifting procedures were performed and 72 dental implants placed in 18 consecutive patients, using the lateral window approach. Clinical and radiological follow-up was conducted throughout the 6-month healing period. Biopsies of 30 cases were collected at 6 months post-treatment: 15 biopsies were taken from the newly formed bone near the basal floor and 15 from the newly formed bone near the elevated membrane. New bone consolidation in the maxillary sinus was apparent radiologically and histologically at 6 months after sinus augmentation, providing an average 6.14±1.34mm of bone-gain. Based on histological analysis and histomorphometric data, the consolidated bone in the augmented sinus comprised 56.7±11.9% to 59.9±13.4% vital bone tissue. Out of the 72 implants placed, only four failed, indicating a 94% overall implant survival rate. Based on this case series, blood clot can be considered autologous osteogenic graft material, to which osteoprogenitors can migrate, differentiate, and regenerate bone.

A numerical investigation of the healthy abdominal wall structures

The present work aims to assess, via numerical modeling, the global passive mechanical behavior of the healthy abdominal wall under the action of pressures that characterize different daily tasks and physiological functions. The evaluation of a normal range of intra-abdominal pressure (IAP) during activities of daily living is fundamental because pressure alterations can cause several adverse effects.At this purpose, a finite element model is developed from literature histomorphometric data and from diagnostic images of Computed Tomography (CT), detailing the different anatomical regions.Numerical simulations cover an IAP up to the physiological limit of 171 (0.0223MPa) mmHg reached while jumping.Numerical results are in agreement with evidences on physiological abdomens when evaluating the local deformations along the craniocaudal direction, the transversal load forces in different regions and the increase of the abdominal area at a IAP of 12mmHg.The developed model can be upgraded for the investigation of the abdominal hernia repair and the assessment of prostheses mechanical compatibility, correlating stiffness and tensile strength of the abdominal tissues with those of surgical meshes.

A Comparison of Vascularity, Bone Mineral Density Distribution, and Histomorphometrics in an Isogenic Versus an Outbred Murine Model of Mandibular Distraction Osteogenesis

The vascularity, bone mineral density distribution, and histomorphometric data between the inbred, isogenic Lewis rat and the outbred, nonisogenic Sprague Dawley rat within mandibular distraction osteogenesis (MDO) were evaluated to allow future researchers to compare the results generated from these 2 animals. We hypothesized that little difference would be found between the 2 strains within these metrics. We implemented a comparative study between the Lewis and Sprague Dawley rat strains within MDO. The sample was composed of 17 male Lewis and 17 male Sprague Dawley rats that underwent surgical external fixation and distraction. The rats' hemimandibles were distracted to a total distance of 5.1mm. After 28days of consolidation, 9 rats from each group underwent bone mineral density distribution analysis. The remaining rats from each group were analyzed for the vascular and histologic metrics. Descriptive and bivariate statistics were computed, and the P value was set at .05. We demonstrated successful MDO in all the rats, with no significant difference found in the histologic or bone mineral density distribution metrics. No significant differences were found in any of the vascular metrics, with the exception of vascular separation, which was not normalized to the mandibular volume (P= .048). The results of the present study have demonstrated that little dissimilarity exists between the isogenic Lewis and outbred Sprague Dawley models of MDO. Thus, researchers can confidently compare the gross results between the 2 strains, with consideration of the very small differences between the 2 models. For studies that require an isogenic strain, the Lewis rat is an apt surrogate for the Sprague Dawley strain.

Influence of three different histological methods on the morphology and morphometrical data in human testis.

Coagulant fixatives and paraffin embedding were widely used in the past for histomorphometrical evaluations of the human testis under physiological and pathological conditions. However, new methods are applied nowadays using better combinations of fixatives and plastic resins as embedding media, improving cell and tissue structural preservation. In an attempt to compare old and new data, the present study evaluated histomorphometrical data obtained from human testis after three different histological processing methods: Bouin/paraplast, glutaraldehyde/glycol methacrylate and glutaraldehyde/araldite. The morphometrical parameters were not affected by glutaraldehyde fixation after both resin embedding (methacrylate or araldite). On the other hand, Bouin/paraplast embedding lead to tissue shrinkage, which could give rise to misinterpretations on the measurements performed. Since some germ and somatic cells recognition do not depend upon high resolution techniques, counting of such cell types could be performed even using routine Bouin/paraplast protocols. Thus, the morphometrical analyses relying on cell recognition were not affected by the methods here applied, however, when metric measurements were applied, the obtained results could not be promptly compared. However, if the study requires confident spermatogonial identification for kinetics evaluation, glutaraldehyde/araldite processing is highly recommended.

Osteophilic properties of bone implant surface modifications in a cassette model on a decorticated goat spinal transverse process

This study comparatively evaluated the osteophilic capacity of 17 different surface modifications (i.e. fourteen different chemical modifications via ceramic coatings and three different physical modifications via surface roughness) for titanium (Ti) surfaces. All surface modifications were subjected to physico-chemical analyses and immersion in simulated body fluid (SBF) for coating stability assessment. Subsequently, a bone conduction chamber cassette model on the goat transverse process was used for comparative in vivo analysis based on bone responses to these different surface modifications after twelve weeks. Histological and histomorphometrical analyses in terms of longitudinal bone-to-implant contact percentage (BIC%), relative bone area (BA%) were investigated within each individual channel and maximum bone height (BH). Characterization of the surface modifications showed significant differences in surface chemistry and surface roughness among the surface modifications. Generally, immersion of the coatings in SBF showed net uptake of calcium by thick coatings (>50μm; plasma-sprayed and biomimetic coatings) and no fluctuations in the SBF for thin coatings (<50μm). The histomorphometrical data set demonstrated that only plasma-sprayed CaP coatings performed superiorly regarding BIC%, BA% and BH compared to un-coated surfaces, irrespective of surface roughness of the latter. In conclusion, this study demonstrated that the deposition of plasma-sprayed CaP coating with high roughness significantly improves the osteophilic capacity of titanium surfaces in a chamber cassette model. Statement of SignificanceFor the bone implant market, a large number of surface modifications are available on different types of (dental and orthopedic) bone implants. As the implant surface provides the interface at which the biomaterial interacts with the surrounding (bone) tissue, it is of utmost importance to know what surface modification has optimal osteophilic properties. In contrast to numerous earlier studies on bone implant surface modifications with limited number of comparison surfaces, the manuscript by van Oirschot et al. describes the data of in vivo experiments using a large animal model that allows for direct and simultaneous comparison of a large variety of surface modifications, which included both commercially available and experimental surface modifications for bone implants. These data clearly show the superiority of plasma-sprayed hydroxyapatite coatings regarding bone-to-implant contact, bone amount, and bone height.

Bone Formation Following Sinus Augmentation with an Equine-Derived Bone Graft: A Retrospective Histologic and Histomorphometric Study with 36-Month Follow-up.

The aim of this study was to investigate bone formation over time following maxillary sinus augmentation with an enzyme-deantigenic, bone collagen-preserving equine bone graft by retrospective assessment of histomorphometric data. Records of patients with atrophic ridges who underwent maxillary sinus augmentation with the enzyme-deantigenic equine bone graft and two-step implant placement between 3 and 12 months after the sinus-augmentation surgery were assessed retrospectively. The histomorphometric data were clustered in three classes according to time of collection from the augmentation surgery and analyzed to assess newly formed bone deposition and residual biomaterial degradation rates. Data concerning the 36-month clinical follow-up were also assessed. Records of 77 patients and 115 biopsy specimens were retrieved, and histomorphometric data were clustered (3 to 5 months, n = 33; 6 to 8 months, n = 57; 9 to 12 months, n = 25). Mean minimum atrophic ridge thickness was 4.9 ± 0.5 mm (range, 4.0 to 7.1 mm). The amount of newly formed bone and residual biomaterial did not significantly differ among the three clusters. Qualitative analysis showed a denser trabecular structure in late (> 8 months) samples. At the 36-month clinical follow-up, no differences were found among the implant success rates in the three groups, according to the Albrektsson and Zarb criteria for success. The overall implant success rate was 98.3%. Based upon this retrospective human study of 77 patients with 4 to 7 mm of residual bone, when enzyme-deantigenic equine bone is used for sinus augmentation, new bone formation occurs at an early time (< 3 months) after the grafting, and implant placement can be safely carried out as soon as 3 to 5 months after the augmentation surgery.

Effects of cisplatin chemotherapy on the osseointegration of titanium implants.

The effect of chemotherapy on the osseointegration of dental implants has received less interest compared with radiotherapy. Thus, the aim of the current study was to investigate the effect of cisplatin chemotherapy on the osseointegration of dental implants in a rabbit model. Sixteen New Zealand White rabbits were randomly assigned to two groups of treatment of either cisplatin at 2.5mg/kg/week for 4 weeks (n=8) or placebo (n=8), in which the first dose was administered 2 days prior to the surgical procedure. Each rabbit received one titanium dental implant inserted in the right distal femoral condyle. Four rabbits from each group were sacrificed 4 and 8 weeks after implant insertion. Osseointegration of the dental implants was analysed using micro-computed tomography and histomorphometric evaluation. Analysis of micro-computed tomography data and histomorphometric data showed that the osseointegration parameters, including the ratio of bone volume to total volume (BV/TV) and bone-implant contact (BIC%) for the cisplatin group, were significantly lower compared to the control group at 4 and 8 weeks. (P≤0.05). Cisplatin chemotherapy had a negative effect on the osseointegration of dental implants when inserted throughout the chemotherapeutic regimens in a rabbit model.

Severe Impaired Bone Formation was Induced by Short-Term Fasting in Adult Mice

The alterations in bone metabolism were associated with food and nutrition. Regrettably is that no studies have analyzed the bone microstructure subjected to complete fasting in mammals. Our study aimed to identify the effects and alterations of complete fasting on bones via histomorphometric analysis in adult female mice. Twelve-week-old C57BL/6J female mice were randomly divided into ad libitum (AL) and two-day complete fasting (FA) groups. Histomorphometry was carried out to analyze the differences in the microstructure of femurs after the experiment period. The histomorphometric data indicated that the bone resorption parameters, including the number of osteoclasts (Mu.N.Oc/B.Pm), osteoclast surface (Oc.S/BS), and eroded surface (ES/BS), were similar between the two groups. However, the bone formation parameters, including the number of osteoblasts (N.Ob/B.Pm) and osteoblast surface (Ob.S/BS), were markedly decreased in the FA group compared with the AL group. Thus, bone formation but not bone resorption was severely impaired following complete fasting. Furthermore, the osteoid surface (OS/BS) was observably reduced, which indicates that the bone mass should be reduced. However, there was no dramatic reduction in the osteoid thickness (O.Th); thus, the bone mass remained relatively stable between the two groups. These findings provide new insights in the increased incidence of osteoporosis in individuals on weight-reduction diets and other bone diseases associated with undernutrition.

Inhibition of titanium-particle-induced inflammatory osteolysis after local administration of dopamine and suppression of osteoclastogenesis via D2-like receptor signaling pathway

Chronic inflammation and extensive osteoclast formation play critical roles in wear-debris-induced peri-implant osteolysis. We investigated the potential impact of dopamine on titanium-particle-induced inflammatory osteolysis in vivo and in vitro. Twenty-eight C57BL/6J mice were randomly assigned to four groups: sham control (PBS treatment), titanium (titanium/PBS treatment), low- (titanium/2 μg kg−1 day−1 dopamine) and high-dopamine (titanium/10 μg kg−1 day−1 dopamine). After 2 weeks, mouse calvariae were collected for micro-computed tomography (micro-CT) and histomorphometry analysis. Bone-marrow-derived macrophages (BMMs) were isolated to assess osteoclast differentiation. Dopamine significantly reduced titanium-particle-induced osteolysis compared with the titanium group as confirmed by micro-CT and histomorphometric data. Osteoclast numbers were 34.9% and 59.7% (both p < 0.01) lower in the low- and high-dopamine-treatment groups, respectively, than in the titanium group. Additionally, low RANKL, tumor necrosis factor-α, interleukin-1β and interleukin-6 immunochemistry staining were noted in dopamine-treatment groups. Dopamine markedly inhibited osteoclast formation, osteoclastogenesis-related gene expression and pro-inflammatory cytokine expression in BMMs in a dose-dependent manner. Moreover, the resorption area was decreased with 10−9 M and 10−8 M dopamine to 40.0% and 14.5% (both p < 0.01), respectively. Furthermore, the inhibitory effect of dopamine was reversed by the D2-like-receptor antagonist haloperidol but not by the D1-like-receptor antagonist SCH23390. These results suggest that dopamine therapy could be developed into an effective and safe method for osteolysis-related disease caused by chronic inflammation and excessive osteoclast formation.

Histomorphometry of the tibia and mandible of healthy female Wistar rats at different stages of growth.

Female Wistar rats are frequently used in experimental models to study hormone and bone pathologies and treatments. Most experimental studies involving histomorphometric evaluation assessed long bones, and few reports also studied mandibular bone. The aim of this work was to clarify and distinguish the age-related histomorphometric changes that occur in the tibia (subchondral bone) and in the mandible (interradicular bone), and thus obtain reference histomorphometric data of healthy female Wistar rats at different growth stages. Three groups of 8 healthy female Wistar rats were euthanized at 6 (GI), 10 (GII), and 14 (GIII) weeks. The tibiae and mandible were resected and histologically processed to obtain H&E stained sections of the tibia and the lower first molar to analyze the following histomorphometric parameters: Bone volume, trabecular width, trabecular number (Th.N)(1/mm), growth cartilage width, hypertrophic cartilage width and number of osteoclasts per area in the tibiae, and bone volume and number of osteoclasts per area N.Oc/mm2 in the interradicular bone of the first lower molar. A significant decrease in subchondral bone volume as a result of a decrease in trabecular number and growth cartilage width was observed in 14-week-old rats. Conversely, interradicular bone volume was found to increase with age. The results highlight the importance of analyzing both types of bone to better understand the response of two different trabecular bones, contributing in turn to decision making regarding treatment strategies and disease management.

The Effect of Interferon-γ and Zoledronate Treatment on Alpha-Tricalcium Phosphate/Collagen Sponge-Mediated Bone-Tissue Engineering.

Inflammatory responses are frequently associated with the expression of inflammatory cytokines and severe osteoclastogenesis, which significantly affect the efficacy of biomaterials. Recent findings have suggested that interferon (IFN)-γ and zoledronate (Zol) are effective inhibitors of osteoclastogenesis. However, little is known regarding the utility of IFN-γ and Zol in bone tissue engineering. In this study, we generated rat models by generating critically sized defects in calvarias implanted with an alpha-tricalcium phosphate/collagen sponge (α-TCP/CS). At four weeks post-implantation, the rats were divided into IFN-γ, Zol, and control (no treatment) groups. Compared with the control group, the IFN-γ and Zol groups showed remarkable attenuation of severe osteoclastogenesis, leading to a significant enhancement in bone mass. Histomorphometric data and mRNA expression patterns in IFN-γ and Zol-injected rats reflected high bone-turnover with increased bone formation, a reduction in osteoclast numbers, and tumor necrosis factor-α expression. Our results demonstrated that the administration of IFN-γ and Zol enhanced bone regeneration of α-TCP/CS implants by enhancing bone formation, while hampering excess bone resorption.

Histomorphometric outcomes after lateral sinus floor elevation procedure: a systematic review of the literature and meta-analysis.

The aim of the present systematic review of the literature was to evaluate biomaterials performances considering new bone formation estimated through histomorphometric analysis of bone biopsies from human subjects after maxillary sinus floor elevation. An electronic and manual search was performed to retrieve articles showing histomorphometric data of bone biopsies performed after sinus floor elevation surgery. Recorded data were statistically analyzed evaluating percentage of new bone volume, residual biomaterial, and connective/soft tissues in the biopsies. A meta-analysis of comparative studies was also performed. After article selection process, 84 articles were included in the quantitative synthesis and 16 of them in the meta-analysis of comparative studies. The use of autogenous bone (AB) alone led to a significantly higher new bone formation if compared with bovine bone (BB) alone (P=0.04), while no significant difference was found when the latter was compared with a mixture of AB and BB (P=0.52). Grafts composed of BB showed significantly greater new bone formation as compared to hydroxyapatite (HA) (P<0.001) while a mixture of tricalcium phosphate (TCP) and HA achieved better outcomes than BB (P<0.001). Based on histomorphometric evaluation, AB should still be taken into consideration when the highest possible new bone formation is the primary aim in maxillary sinus surgery. When donor site morbidity is a concern, BB and a mixture of TCP and HA could be considered as predictable, showing promising results. More comparative histologic studies are needed to confirm such results.

The effect of platelet-rich fibrin on bone regeneration and angiogenesis in rabbit cranial defects

This study evaluated the effect of platelet-rich fibrin (PRF) on the osteogenesis and angiogenesis of rabbit calvarial defects. The calvarium of nine rabbits was exposed. In each rabbit, two circular bone defects, one on each side of the midline, were prepared using a reamer drill. While the experimental site received PRF, the control sites were left filled with blood. The animals were sacrificed after a period of 1 week (n=3), 2 weeks (n=3), and 4 weeks (n=3). The following histomorphometric data were recorded: 1) the area of the newly formed tissue relative to total bone defect (NT) and the area of newly formed osteoid relative to newly formed tissue (NB), 2) the longest and shortest vertical height of the newly formed tissue relative to the vertical height of normal tissue (LH, SH), 3) newly formed osteoid on the defect margin using region of interest (NBR), and 4) bony pontic formation from the margin was used to evaluate bone growth (OS). The expression of vascular endothelial growth factor (VEGF) was evaluated by immunohistochemical staining. The differences between groups were not significant at any experimental time point. However, a significant linear increase of NB and NBR including OS value according to time was observed in the PRF group. In addition, the intensity and percentage range of VEGF expression showed a significant linear decrease trend with the time in the PRF group. The results of this study suggest that PRF may enhance the quality of bone regeneration.

The effect of platelet-rich fibrin on bone regeneration and angiogenesis in rabbit cranial defects

This study evaluated the effect of platelet-rich fibrin (PRF) on the osteogenesis and angiogenesis of rabbit calvarial defects. The calvarium of nine rabbits was exposed. In each rabbit, two circular bone defects, one on each side of the midline, were prepared using a reamer drill. While the experimental site received PRF, the control sites were left filled with blood. The animals were sacrificed after a period of 1 week (n=3), 2 weeks (n=3), and 4 weeks (n=3). The following histomorphometric data were recorded: 1) the area of the newly formed tissue relative to total bone defect (NT) and the area of newly formed osteoid relative to newly formed tissue (NB), 2) the longest and shortest vertical height of the newly formed tissue relative to the vertical height of normal tissue (LH, SH), 3) newly formed osteoid on the defect margin using region of interest (NBR), and 4) bony pontic formation from the margin was used to evaluate bone growth (OS). The expression of vascular endothelial growth factor (VEGF) was evaluated by immunohistochemical staining. The differences between groups were not significant at any experimental time point. However, a significant linear increase of NB and NBR including OS value according to time was observed in the PRF group. In addition, the intensity and percentage range of VEGF expression showed a significant linear decrease trend with the time in the PRF group. The results of this study suggest that PRF may enhance the quality of bone regeneration.

Comparative study of two types of herbal capsules with different Epimedium species for the prevention of ovariectomised-induced osteoporosis in rats

SummaryBackground/ObjectiveEpimedii Folium is the most important osteogenic herb formulated for the traditional Chinese Medicine Xian Ling Gu Bao (XLGB) capsule. The present study compared XLGB capsules containing two different Epimedium species, i.e., either Epimedium pubescens (XEP) or Epimedium koreanum (XEK), with the focus being on the chemical constituents and antiosteoporotic efficacy.MethodsUltra performance liquid chromatography was used to demonstrate the different chemical constituents. Biomechanical tests, histological, and cytological evaluation were performed to characterise and compare the bone mineral density, bone strength, microstructure of bone tissue, and biological activity between XEP and XEK using an established ovariectomised (OVX) rat model.ResultsSix flavonoids with different contents between XEK and XEP were identified. As compared with the OVX group, significantly higher bone mineral density, elastic-modulus, and compressive strength were found in both the XEK group and XEP group (p < 0.05 for all, n = 8). Histomorphometric data presented significantly higher osteoblast surface ratio and osteoid area accompanied by significantly lower values of erosion surface and adiopocytes area in two treatment groups (p < 0.05, n = 6). XLGB Fufang with either XEK or XEP all showed significant preventive effects in OVX-induced osteoporosis and deterioration of bone mechanical properties.ConclusionThe significance of the current preclinical experimental study was that these two Epimedium species used for formulating XLGB capsules were equally effective for the prevention of oestrogen-depletion induced osteoporosis.

Biomechanical behavior of plantar fat pad in healthy and degenerative foot conditions.

The plantar fat pad of the human foot is a specific tissue made up of adipose chambers enveloped by fibrous septa. Aging, pathology or trauma may affect its histo-morphological configuration and mechanical response. The correlation between histo-morphological configuration and mechanical properties is analyzed by a computational approach, aiming to identify the influence of degenerative phenomena on plantar fat pad mechanics. Finite element meso-models, as numerical model of an intermediate-length scale, are developed for healthy and degenerative conditions, considering the different properties that degenerative phenomena may affect, such as the adipose chambers dimension, the fibrous septa thickness, the fibers orientation and the sub-components mechanical behavior. Histo-morphometric data are analyzed to identify average configurations of the fat chambers and fibrous septa, while specific constitutive formulations are provided to define their mechanical response. Numerical analyses are performed to identify the stress-strain behavior of the plantar fat pad considering healthy and degenerative configurations. The results from meso-models are applied to identify the parameters of a phenomenological constitutive formulation that interprets the overall human fat pad tissue mechanics. The constitutive formulation is implemented within a 3D finite element model of the heel region that is applied to evaluate the influence of degenerative phenomena on the overall mechanical functionality of the foot.