Bone Volume Over Total Volume Research Articles

Protective effect and possible mechanisms of resveratrol in animal models of osteoporosis: A preclinical systematic review and meta-analysis.

Resveratrol (RES) has extensively been utilized to treat osteoporosis (OP) in animal models. However, the anti-OP effects of RES have not been tested during clinical application due to the lack of evidence and poor knowledge of the underlying mechanisms. Moreover, there is little preclinical evidence to support the use of RES in the management of OP. In the present paper, we conducted a preclinical systematic review and meta-analysis to assess the efficacy of RES in animal OP models. The potential mechanisms underlying the efficacy of RES against OP were summarized. The online databases PubMed, CNKI, EMBASE, Wanfang, Web of Science, Chinese Biomedical Literature, Cochrane Library, and Chinese VIP were retrieved from inception to December 2021. The CAMARADES 10-item quality checklist was utilized to assess the risk of bias of the included studies. STATA 12.0 software was employed to analyze the data. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Thirteen studies containing 248 animals were included yielding a mean risk of bias score of 5.54 (range 4-7). The pooled estimates showed that the administration of RES could significantly elevate the bone mineral density (BMD) both at femur (SMD = 2.536; 95% CI = 1.950-3.122; p < 0.001) and lumbar spine (SMD = 1.363; 95% CI = 0894-1.832; p < 0.001), bone volume over total volume (BV/TV) (SMD = 2.543; 95% CI = 2.023-3.062; p < 0.001), trabecular linear density (Tb.N) (SMD = 2.724; 95% CI = 2.186-3.262; p < 0.001) and trabecular thickness (Tb.Th) (SMD = 1.745; 95% CI = 1.294-2.196; p < 0.001), while serum phosphorus (S-P) (SMD = -2.168; 95% CI = -2.753 to -1.583; p < 0.001) and trabecular separation (Tb.Sp) (SMD = -2.856; 95% CI = -4.218 to -1.494; p < 0.001) were significantly reduced in animal OP models. No significant change in serum calcium (S-Ca) (SMD = -2.448; 95% CI = -5.255-0.360; p = 0.087) was observed after RES treatment. Furthermore, RES could significantly improve the bone biomechanical indexes: bone maximum load (BML) (SMD = 2.563; 95% CI = 1.827-3.299; p < 0.001) and connectivity density (Conn.D) (SMD = 1.512; 95% CI = 0.909-2.116; p < 0.001) and decrease the structural model index (SMI) (SMD = -2.522; 95% CI = -3.243 to -1.801; p < 0.001). Overall, the present study revealed that RES has huge prospects as a medicine or dietary supplement for the clinical treatment of OP. High-quality studies with stringent designs and larger sample sizes are warranted to substantiate our conclusion.

Abstract 3828: Herbal extracts from lycii radicis corex and achyranthes japonica prevent multiple myeloma progression

Abstract Multiple Myeloma (MM) is a plasma cell malignancy that, despite advances in treatment, remains incurable. In over 90% of MM patients, aberrant bone remodeling occurs and results in osteolytic lesions. Korean traditional medicine has a long-standing interest in healthy foods to enhance the immune system, energy-boost, and Yin-and-Yang balance. Traditional medicine has used herbal extracts (HE) from natural plants with fewer side effects and long-term treatment tolerance. In earlier studies, lycii radices cortex (LRC) and achyranthes japonica (AJ) containing HE have demonstrated the ability to enhance cell growth and mineralization of osteoblast cells while also inhibiting osteoclast differentiation. The current study investigated the effects of LRC+AJ containing HE on murine 5TGM1 MM-bearing mice.This HE significantly increased the mouse survivals of both Treatment before Transplant (TbT) and Treatment after Transplant (TaT) groups with median survivals of undetermined and 52.5 days, respectively, while MM control had a median survival of 42 days. The Mantel-Cox test found that TbT and TaT mice were significantly different from the control group (P=0.0014 and 0.0182, respectively). In histomorphometric analysis, the spines were scanned by micro-CT and revealed that TbT and TaT groups had significantly increased bone volume over total volume (BV/TV) than control. To see if HE affects cell growth of myeloma cells and osteoblast cells, we further investigated the HE on preosteoblast cell line MC3T3-E1, mouse MM cell line 5TGM1-Luc, and human MM cell line U-266. Cells were treated with HE, and viability was assessed at 48 and 96 hours post-treatment. Remarkably, LRC+AJ containing HE increased MC3T3-E1 cell growth while it decreased 5TGM1 and U-266 cell viability. In addition, we found the DAP3G in HE used in this study.Our results demonstrated that LRC+AJ HE prevents MM and promotes bone formation in 5TGM1 engrafted NSG mice. We also found that LRC+AJ HE suppresses myeloma cell growth and enhances osteoblast cell survival. Although it is yet to be defined, a correlation of osteoblast activity and myeloma cell inhibition suggests a possible connection of these events to prevent MM progression. Citation Format: Syed Hassan Mehdi, Sun-OK Lee, Dam Huh, Donghoon Yoon. Herbal extracts from lycii radicis corex and achyranthes japonica prevent multiple myeloma progression. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3828.

Loss of early B cell protein λ5 decreases bone mass and accelerates skeletal aging.

The early B cell protein λ5 is an essential component of the surrogate light chain and the preB cell receptor (preBCR), which is critical for optimal B cell development. To investigate the effect of λ5 and/or B cells on bone acquisition over time, we developed a panel of JH -/- , λ5-/-, JH -/- λ5-/-, and wild-type (WT) BALB/c mice and then studied postnatal bone development and aging in these mice at one, six, twelve, and twenty-two months of age. The trabecular bone volume over total volume (BV/TV) in JH -/- mice was similar to WT mice at all ages. In contrast, at six months of age and thereafter, λ5-/- and JH -/- λ5-/- mice demonstrated a severe decrease in trabecular bone mass. Surprisingly, bone mass in six-month-old λ5-/- and JH -/- λ5-/- mice was similar to or even lower than in aged (twenty-two-months) WT mice, suggesting accelerated skeletal aging. The postnatal development and the acquisition of cortical bone mass in JH -/- λ5-/- mice were generally comparable to WT. However, JH -/- λ5-/- mice showed a significant decrease in cortical BV/TV at six- and twelve months of age. To examine the contribution of λ5 and B cells to postnatal bone synthesis, we separately transplanted whole bone marrow cells from JH -/- λ5-/- and WT mice into irradiated JH -/- λ5-/- and WT recipients. WT recipients of JH -/- λ5-/- marrow cells failed to show acquisition of trabecular bone mass, whereas transplanting WT marrow cells into JH -/- λ5-/- recipients led to the recovery of trabecular bone mass. Transfer of WT marrow cells into JH -/- λ5-/- mice promoted synthesis of new cortical and trabecular bone. Our findings indicate that λ5 plays a major role in preserving bone mass during postnatal development and skeletal aging which is distinct from its role in B cell development. The absence of both λ5 and B cells in JH -/- λ5-/- mice leads to delayed acquisition of cortical bone during postnatal development. Dissecting the mechanism(s) by which λ5 regulates bone homeostasis may provide new avenues for the treatment of age-related loss of bone mass and osteoporosis.

Herbal Extracts from Lycii Radicis Corex and Achyranthes japonica Prevent Multiple Myeloma

IntroductionMultiple Myeloma (MM) is a plasma cell malignancy that, despite advances in treatment, remains incurable. In over 90% of MM patients, aberrant bone remodeling occurs and results in osteolytic lesions. It severely reduces the patient's quality of life and increases mortality. Korean traditional medicine has a long-standing interest in healthy foods to enhance the immune system, energy-boost, and Yin-and-Yang balance. A healthy diet in Tradition medicine is based on accumulated observations from countless cases over multi-centuries. Traditional medicine has used herbal extracts (HE) from natural plants with fewer side effects and long-term treatment tolerance. In earlier studies, lycii radices cortex (LRC) and achyranthes japonica (AJ) containing herbal extracts (HE) have demonstrated the ability to enhance cell growth and mineralization of osteoblast cells while also inhibiting osteoclast differentiation. Furthermore, a sesquiterpene glucoside, (1'R,3'S,5'R,8'S,2 Z,4 E)-dihydrophaseic acid 3'-O-β-d-glucopyranoside (DPA3G) were isolated from the LRC ethanol extract and shown to be a bioactive compound for enhancement of cell growth and bone anabolic activity (Park et al). The current study investigated the effects of LRC+AJ containing HE on murine 5TGM1 MM-bearing mice.MethodsWe transplanted 1x10 6 cells of the enforced luciferase-expressing 5TGM1 (5TGM1-Luc) into 8~12-week-old Nod-Scid-IL2Rg null (NSG) mice via tail vein (representing an equal number of each sex). For LRC+AJ containing HE treatment, mice were divided into three groups; i) PBS group; ii) treatment group at 300 mg/kg, gavage, TIW started two weeks before MM transplant (TbT); and iii) treatment group at 300 mg/kg, gavage, TIW two weeks after MM transplant (TaT). We assessed tumor burden by weekly bioluminescence imaging (IVIS 200 Imager, Perkin Elmer). The spine was extracted from carcass and scanned at postmortem by Dual Energy X-ray Absorptiometry using PIXImus Densitometer (G.E. Lunar, Madison, USA) and micro-computed tomography (microCT; Scanco Medical AG, Switzerland).HE effects in cell growth were tested in the myeloma cells (5TGM1 and U266) and preosteoblast cells (MC3T3-E1). The cells were grown in various concentrations (8, 80, 800 ug/ml) of HE up to 96 hours. In addition, Chromatogram and Mass Spectrometry were conducted to identify the DPA3G.ResultsAs shown in Figure 1A, this HE significantly increased the mouse survivals of both TbT and TaT groups with median survivals of undetermined and 52.5 days, respectively, while MM control had a median survival of 42 days. The Mantel-Cox test found that TbT and TaT mice were significantly different from the control group (P=0.0014 and 0.0182, respectively). Furthermore, DEXA scans at postmortem showed a significant increase in bone mineral density (BMD) and bone mineral content (BMC) in TbT and TaT groups than control MM mice. For a histomorphometry analysis, the spines were scanned by micro-CT and revealed that TbT and TaT groups had significantly increased bone volume over total volume (BV/TV) than control. To see if HE affects cell growth of myeloma cells and osteoblast cells, we further investigated the HE on preosteoblast cell line MC3T3-E1, mouse MM cell line 5TGM1-Luc, and human MM cell line U-266. Cells were treated with HE in various concentrations, and viability was assessed at 48 and 96 hours post-treatment. Remarkably, LRC+AJ containing HE increased MC3T3-E1 cell growth while it decreased 5TGM1 and U-266 cell viability. We identified the DAP3G and many other compounds in HE used in this study.ConclusionsOur results demonstrated that LRC+AJ HE prevents MM and promotes bone formation in 5TGM1 engrafted NSG mice. We also found that LRC+AJ HE suppresses myeloma cell growth and enhances osteoblast cell survival. Although it is yet to be defined, a correlation of osteoblast activity and myeloma cell inhibition suggests a potential mechanism of the HE action to prevent MM progression.1. Park E, Kim J, Yeo S, Lim E, Choi CW, Choi S, Li WY, Lee JW, Park JH, Huh D, Jeong SY. Anti-Osteoporotic Effects of Combined Extract of Lycii Radicis Cortexand Achyranthes japonica in Osteoblast and Osteoclast Cells and Ovariectomized Mice. Nutrients. 2019 Nov 9;11(11):2716. doi: 10.3390/nu11112716. PMID: 31717518; PMCID: PMC6893723.' [Display omitted] DisclosuresHuh: Dongwoodang Pharmacy Company: Current Employment. OffLabel Disclosure:Herbal Extracts from Lycii Radicis Corex and Achyranthes Japonica

Early bone ingrowth and segmental stability of a trussed titanium cage versus a polyether ether ketone cage in an ovine lumbar interbody fusion model

BACKGROUND CONTEXTLumbar interbody fusion is an effective treatment for unstable spinal segments. However, the time needed to establish a solid bony interbody fusion between the two vertebrae may be longer than twelve months after surgery. During this time window, the instrumented spinal segment is assumed to be at increased risk for instability related complications such as cage migration or subsidence. It is hypothesized that the design of new interbody cages that enable direct osseointegration of the cage at the vertebral endplates, without requiring full bony fusion between the two vertebral endplates, might shorten the time window that the instrumented spinal segment is susceptible to failure. PURPOSETo quantify the bone ingrowth and resulting segmental stability during consolidation of lumbar interbody fusion using two different cage types. STUDY DESIGNPreclinical ovine model. METHODSSeven skeletally mature sheep underwent bi-segmental lumbar interbody fusion surgery with one conventional polyether ether ketone (PEEK) cage, and one newly developed trussed titanium (TT) cage. After a postoperative time period of 13 weeks, non–destructive range of motion testing, and histologic analysis was performed. Additionally, sample specific finite element (FE) analysis was performed to predict the stability of the interbody fusion region alone. RESULTSPhysiological movement of complete spinal motion segments did not reveal significant differences between the segments operated with PEEK and TT cages. The onset of creeping substitution within the cage seemed to be sooner for PEEK cages, which led to significantly higher bone volume over total volume (BV/TV) compared with the TT cages. TT cages showed significantly more direct bone to implant contact (BIC). Although the mean stability of the interbody fusion region alone was not statistically different between the PEEK and TT cages, the variation within the cage types illustrated an all-or-nothing response for the PEEK cages while a more gradual increase in stability was found for the TT cages. CONCLUSIONSSpinal segments operated with conventional PEEK cages were not different from those operated with newly developed TT cages in terms of segmental stability but did show a different mechanism of bone ingrowth and attachment. Based on the differences in development of bony fusion, we hypothesize that TT cages might facilitate increased early segmental stability by direct osseointegration of the cage at the vertebral endplates without requiring complete bony bridging through the cage. CLINICAL SIGNIFICANCEInterbody cage type affects the consolidation process of spinal interbody fusion. Whether different consolidation processes of spinal interbody fusion result in clinically significant differences requires further investigation.

FasL Is Required for Osseous Healing in Extraction Sockets in Mice.

Fas ligand (FasL) is a member of the tumor necrosis factor (TNF) superfamily involved in the activation of apoptosis. Assuming that apoptosis is initiated after tooth extraction it is reasonable to suggest that FasL may play a pivotal role in the healing of extraction sockets. Herein, we tested the hypothesis of whether the lack of FasL impairs the healing of extraction sockets. To this end, we extracted upper right incisors of FasL knockout (KO) mice and their wildtype (WT) littermates. After a healing period of two weeks, bone volume over total volume (BV/TV) via µCT and descriptive histological analyses were performed. µCT revealed that BV/TV in the coronal region of the socket amounted to 39.4% in WT and 21.8% in KO, with a significant difference between the groups (p=0.002). Likewise, in the middle region of the socket, BV/TV amounted to 50.3% in WT and 40.8% in KO (p<0.001). In the apical part, however, no difference was noticed. Consistently, WT mice displayed a significantly higher median trabecular thickness and a lower trabecular separation when compared to the KO group at the coronal and central region of the socket. There was the overall tendency that in both, female and male mice, FasL affects bone regeneration. Taken together, these findings suggest that FasL deficiency may reduce bone regeneration during the healing process of extraction sockets.

In Vivo and In Vitro Analyses of Titanium-Hydroxyapatite Functionally Graded Material for Dental Implants.

Purpose The stress shielding effect caused due to the mechanical mismatch between the solid titanium and the surrounding bone tissue warrants the utilization of a mechanically and biologically compatible material such as the titanium-hydroxyapatite (Ti-HA) functionally graded material (FGM) for dental implants. This study is aimed at fabricating a Ti-HA FGM with superior mechanical and biological properties for dental implantation. Materials and Methods We fabricated a Ti-HA FGM with different Ti volume fractions (VFs) using HA and Ti powders. Ti-HA was characterized by studying its mechanical properties. Cytotoxicity was examined using a Cell Counting Kit-8 assay and an LDH cell cytotoxicity assay. Scanning electron microscopy was performed on an XL30 environmental scanning electron microscope (ESEM). Alkaline phosphatase (ALP) and transforming growth factor (TGF-β1) expressions were quantitatively monitored using enzyme-linked immunosorbent assay (ELISA) kits. The expressions of TGF-β receptors and ALP genes were measured using real-time polymerase chain reaction. The Ti-HA FGM dental implants were placed in beagle dogs. Microcomputed tomography (CT) and hard tissue slices were performed to evaluate the bone-implant contact (BIC) and bone volume over total volume (BV/TV). Results The density and mechanical properties of the Ti-HA exhibited various graded distributions corresponding to VF. Based on the results of the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays, the difference in cytotoxicity between the two groups was statistically nonsignificant (P = 0.11). The ALP and TGF-β1 levels were slightly upregulated. The transcript levels of ALP and TGF-βRI were higher in the Ti-HA groups than in the Ti group at 7 days, whereas the transcript levels of TGF-βRII exhibited no obvious increase. The BIC did not exhibit significant differences between the Ti and Ti-HA FGM groups (P = 0.0504). BV/TV showed the Ti-HA FGM group had better osteogenesis (P = 0.04). Conclusion Ti-HA FGM contributes to the osteogenesis of dental implants in vivo and in vitro.

Antiosteoporosis Effect and Possible Mechanisms of the Ingredients of Fructus Psoraleae in Animal Models of Osteoporosis: A Preclinical Systematic Review and Meta-Analysis.

Objective Fructus Psoraleae (FP) and its ingredients (IFP) have a variety of biological activities and are widely used to treat osteoporosis (OP). Herein, we conducted a systematic review to evaluate the efficacy of IFP for an animal model of OP from the current literatures. Potential mechanisms of IFP in the treatment of OP were also summarized. Materials and Methods We carried out a search for electronic literature in the PubMed, Chinese National Knowledge Infrastructure, EMBASE, Wanfang, Web of Science, Chinese Biomedical Literature Database, and Cochrane Library, as well as Chinese VIP databases targeting articles published from inception to June 2021. The inclusion criteria were animal studies that assessed the efficacy and safety of IFP for OP, regardless of publication status or language. The exclusion criteria included (1) other types of studies (in vitro studies, case reports, clinical trials, reviews, abstracts, comments, and editorials), (2) combination with other compounds, (3) compared with other traditional Chinese medicine, (4) not osteoporosis or bone loss model, (5) studies with insufficient data, (6) lack of a control group, and (7) duplicate publications. The modified Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Stroke (CAMARADES) 10-item quality checklist was used to evaluate the risk of bias of included studies. We computed the relative risk (RR) and the standard mean difference (SMD) for dichotomous outcomes and continuous outcomes, respectively. When heterogeneity was detected or there was significant statistical heterogeneity (P < 0.05 or I2 > 50%), a random-effects model was employed, followed by further subgroup analysis and metaregression estimations to ascertain the origins of heterogeneity. Otherwise, we used a fixed-effects model (P ≥ 0.05 or I2 ≤ 50%). The primary outcome measures were bone mineral density (BMD), serum osteocalcin(S-OCN), bone volume over total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), bone maximum load, and elasticity modulus. The secondary outcome measure was the antiosteoporosis mechanisms of IFP. The STATA 12.0 software was used to analyze the data. Results Overall, 16 studies focusing on 379 animals were enrolled into the study. The risk of bias score of included studies ranged from 4 to 7 with an average score of 5.25. The present study provided the preliminary preclinical evidence that administration of IFP could significantly increase the S-OCN, BMD, BV/TV, and Tb.N while Tb.Th and Tb.Sp were remarkably decreased by IFP in OP model animals (P < 0.05). Moreover, IFP could significantly improve the bone biomechanical indicator bone maximum load and elasticity modulus (P < 0.05). In terms of the possible mechanisms of treatment of OP, IFP exerts anti-OP effects in animal models probably through osteoprotegerin/receptor activator of the nuclear factor-κB ligand/receptor activator of nuclear factor-κB (OPG/RANKL/RANK), peroxisome proliferator activated receptor γ (PPAR-γ)/Axin2/Wnt, antioxidative stress via forkhead box O3a (FoxO3a)/Axin2/Wnt, phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR), estrogen-like effect, and gamma-aminobutyric acid/gamma-aminobutyric acid receptor (GABA/GABABRI) signaling pathway. Conclusion Taken together, the findings suggest the possibility of developing IFP as a drug or an ingredient in diet for the clinical treatment of OP. We recommend that rigorous, as well as high-quality, trials involving large sample sizes should be conducted to confirm our findings.

Gut Microbiome Dysbiosis Alleviate the Progress of Osteoarthritis in Mice

Objective: To evaluate the contribution of gut microbiota dysbiosis on the development of osteoarthritis (OA) in different gender mice. Design: We used a mouse OA model (8 weeks) of the destabilization of the medial meniscus(DMM) and gut microbiome dysbiosis induced by antibiotic treatment (ABT) with ampicillin and neomycin for 8 weeks. The severity of OA was evaluated by micro-CT scanning, X-rays and the Osteoarthritis Research Society International (OARSI) histology score. Microbiome analysis via PCR of 16S DNA was performed on fecal samples, and the serum LPS, IL-6, TNF-α, osteocalcin, estrogen, calcium and magnesium ion levels were measured by enzyme-linked immunosorbent assay (ELISA). Finding: Compared to those in normal mice, the bone volume over total volume (BV/TV) (P<0.01) and the OARSI score (P<0.01) in subchondral bone decreased significantly in the female and male ABT treatment groups. ABT decreased the osteophyte score in female mice in the standard normal group (P<0.05) and decreased the osteophyte maturity score in both female (P<0.01) and male (P<0.05) mice. The levels of IL-6 (P<0.01), TNF-α (P<0.01 for both subgroups), calcium (P<0.01) and expression of MMP-13 were decreased significantly in the ABT group compared with those in the control group, while magnesium and estrogen were increased significantly in the ABT-female group compared with those in the control-female group (P<0.01). For DMM surgery treatment, BV/TV (P<0.01) and serum level of IL-6 (P<0.01) were decreased significantly but the ratio of serum level of Ca2+ and Mg2+ increased significantly in male mice compare than female mice. the bone volume over total volume (BV/TV) of subchondral bone sclerosis has been increased significant in female mice after joint injury than male mice. However, trabecular thickness (Tb.Th) and osteophyte score have been increased significantly in antibiotic-induced male mice than female mice. We further used network correlations analysis to verify the effect of gut microbiota dysbiosis on OA. Interpretation: Our data showed the factors to the gut microbiome dysbiosis alleviating the progression of OA. Funding Statement: This work was partly supported by the National Natural Science Foundation of China (Grants no. 81874010, 81672133). Declaration of Interests: The authors have declared that no conflict of interest exists. Ethics Approval Statement: The experiments and protocol were approved by The Peking University Third Hospital Committee on Ethics in the Care and Use of Laboratory Animals (No. LA2019209).

Complement 3 mediates periodontal destruction in patients with type 2 diabetes by regulating macrophage polarization in periodontal tissues.

ObjectivesDiabetes aggravates the risk and severity of periodontitis, but the specific mechanism remains confused. Complement 3 (C3) is closely related to complications of type 2 diabetes (T2DM). In the present study, we concentrated on whether C3 mediates the development of periodontitis in T2DM.Materials and MethodsLevels of C3 in blood and gingival crevicular fluid (GCF) of patients were measured first. A C3‐knockout diabetic mouse model was established, real‐time PCR, Western blotting and histological investigation were performed to evaluate the progress of periodontitis. Microcomputed tomography (micro‐CT) and TRAP staining were performed to detect alveolar bone resorption. Immunofluorescence was performed to detect polarization of macrophages.ResultsOur data showed that C3 levels were elevated in the blood and GCF of T2DM patients compared with non‐diabetic individuals. Increased C3 was closely related to the upregulation of inflammatory cytokines including interleukin (IL)‐1, IL‐6 and tumour necrosis factor‐alpha (TNF‐α), as well as the decline of the bone volume density (BMD) and bone volume over total volume (BV/TV) of the alveolar bones in diabetic mice. The deletion of C3 inhibited inflammatory cytokines and rescued the decreased BMD and BV/TV of the alveolar bones. C3‐mediated polarization of macrophages was responsible for the damage.ConclusionT2DM‐related upregulation of C3 contributes to the development of periodontitis by promoting macrophages M1 polarization and inhibiting M2 polarization, triggering a pro‐inflammatory effect on periodontal tissues.

Staphylococcal enterotoxin C2 promotes osteogenesis of mesenchymal stem cells and accelerates fracture healing.

ObjectivesAs one of the heat-stable enterotoxins, Staphylococcal enterotoxin C2 (SEC2) is synthesized by Staphylococcus aureus, which has been proved to inhibit the growth of tumour cells, and is used as an antitumour agent in cancer immunotherapy. Although SEC2 has been reported to promote osteogenic differentiation of human mesenchymal stem cells (MSCs), the in vivo function of SCE2 in animal model remains elusive. The aim of this study was to further elucidate the in vivo effect of SCE2 on fracture healing.Materials and MethodsRat MSCs were used to test the effects of SEC2 on their proliferation and osteogenic differentiation potentials. A rat femoral fracture model was used to examine the effect of local administration of SEC2 on fracture healing using radiographic analyses, micro-CT analyses, biomechanical testing, and histological analyses.ResultsWhile SEC2 was found to have no effect on rat MSCs proliferation, it promoted the osteoblast differentiation of rat MSCs. In the rat femoral fracture model, the local administration of SEC2 accelerated fracture healing by increasing fracture callus volumes, bone volume over total volume (BV/TV), and biomechanical recovery. The SEC2 treatment group has superior histological appearance compared with the control group.ConclusionThese data suggest that local administration of SEC2 may be a novel therapeutic approach to enhancing bone repair such as fracture healing.Cite this article: T. Wu, J. Zhang, B. Wang, Y. Sun, Y. Liu, G. Li. Staphylococcal enterotoxin C2 promotes osteogenesis of mesenchymal stem cells and accelerates fracture healing. Bone Joint Res 2018;7:179–186. DOI: 10.1302/2046-3758.72.BJR-2017-0229.R1.

The protective effects of triptolide on age-related bone loss in old male rats

BackgroundPrevious studies have showed that triptolide have a critical role in inhibiting osteoclast formation, bone resorption and attenuating regional osteoporosis. However, the protective role of triptolide on age-related bone loss has not been investigated. In the study, we assessed the effect of triptolide supplementation on bone microstructure and bone remolding in old male rat lumbars. MethodsFifty-two 22-month-old male Sprague-Dawley rats were randomly assigned to either triptolide treatment group or control group. Triptolide (15 μg/kg/d) or normal saline was administered to the rats of assigned group for 8 weeks. Lumbar bone mineral density (BMD) and bone microstructure were analyzed by micro-CT. Fluorochrome labeling of the bones was performed to measure the mineral apposition rate (MAR) and bone formation rate (BFR). Osteoclast number was also measured by TRAP staining. Plasma level of osteocalcin and tartrate-resistant acid phosphatase 5b (Tracp 5b) was also analyzed. ResultsMicro-CT results revealed that triptolide-treated rats had significant higher BMD, bone volume over total volume (BV/TV), trabecular thickness (Tb.Th), bone trabecular number (Tb.N), and lower trabecular separation (Tb.Sp) compared to the control group. Although fluorochrome labeling result showed no significant difference in MAR and BFR between the groups, triptolide decreased osteoclast number in vivo. In addition, a significant higher level of plasma Tracp 5b was observed in the triptolide-treated rats. Furthermore, triptolide also reduced the expression of receptor for activation of NF-κB ligand (RANKL) and increased osteoprotegerin (OPG) expression in the lumbars. ConclusionThese results suggested that triptolide had a protective effect on age-related bone loss at least in part by reducing osteoclast number in elder rats. Therefore, triptolide might be a feasible therapeutic approach for senile osteoporosis.

Blockade of NF-κB and MAPK pathways by ulinastatin attenuates wear particle-stimulated osteoclast differentiation invitro and invivo.

Ulinastatin, a urinary trypsin inhibitor (UTI), is widely used to clinically treat lipopolysaccharide (LPS)-related inflammatory disorders recently. Adherent pathogen-associated molecular patterns (PAMPs), of which LPS is the best-studied and classical endotoxin produced by Gram-negative bacteria, act to increase the biological activity of osteopedic wear particles such as polymethyl-methacrylate (PMMA) and titanium particles in cell culture and animal models of implant loosening. The present study was designed to explore the inhibitory effect of UTI on osteoclastogenesis and inflammatory osteolysis in LPS/PMMA-mediated Raw264.7 cells and murine osteolysis models, and investigate the potential mechanism. The in vitro study was divided into the control group, LPS-induced group, PMMA-stimulated group and UTI-pretreated group. UTI (500 or 5000 units/ml) pretreatment was followed by PMMA (0.5 mg/ml) with adherent LPS. The levels of inflammatory mediators including tumour necrosis factor-α (TNF-α), matrixmetallo-proteinases-9 (MMP-9) and interleukin-6 (IL-6), receptor activation of nuclear factor NF-κB (RANK), and cathepsin K were examined and the amounts of phosphorylated I-κB, MEK, JNK and p38 were measured. In vivo study, murine osteolysis models were divided into the control group, PMMA-induced group and UTI-treated group. UTI (500 or 5000 units/kg per day) was injected intraperitoneally followed by PMMA suspension with adherent LPS (2×108 particles/25 μl) in the UTI-treated group. The thickness of interfacial membrane and the number of infiltrated inflammatory cells around the implants were assessed, and bone mineral density (BMD), trabecular number (Tb.N.), trabecular thickness (Tb.Th.), trabecular separation (Tb.Sp.), relative bone volume over total volume (BV/TV) of distal femur around the implants were calculated. Our results showed that UTI pretreatment suppressed the secretion of proinflammatory cytokines including MMP-9, IL-6, TNF-α, RANK and cathepsin K through down-regulating the activity of nuclear factor kappa B (NF-κB) and MAPKs partly in LPS/PMMA-mediated Raw264.7 cells. Finally, UTI treatment decreased the inflammatory osteolysis reaction in PMMA-induced murine osteolysis models. In conclusion, these results confirm the anti-inflammatory potential of UTI in the prevention of particle disease.

Combination of Weight-Bearing Training and Anti-MSTN Polyclonal Antibody Improve Bone Quality In Rats.

Weight-bearing exercise is beneficial to bone health. Myostatin (MSTN) deficiency has a positive effect on bone formation. We wondered if a combination of weight-bearing training and polyclonal antibody for MSTN (MsAb) would augment bone formation to a greater degree than single treatment. In this study, rats were randomly assigned to four groups: Control, weight-bearing training (WT), MsAb, and WT+MsAb. The trained rats ran at 15 m/min bearing with 35% of their body weight, 40 min/day (2 min of running followed by 2 min of rest), 6 days/week, for 8 weeks. The rats with MsAb were injected once a week with MsAb for 8 weeks. MicroCT analysis showed that compared with the MsAb group, WT+MsAb significantly enhanced cortical bone mineral density (BMD) (p < .01), bone volume over total volume (BV/TV) (p < .01), trabecular thickness (p < .05), and reduced trabecular separation (Tb.Sp) (p < .01). Compared with the WT group, WT+MsAb significantly increased trabecular BMD (p < .05), BV/TV (p < .05), and decreased Tb.Sp (p < .05). Three-point bending test demonstrated that MsAb failed to improve bone biomechanical properties (p > .05), weight-bearing training significantly increased energy absorption (p < .05) and elastic modulus (p < .05). However, when they combined, biomechanical properties including maximum load (p < .05), stiffness (p < .05), elastic modulus (p < .01) and energy absorption (p < .01) were all significantly enhanced. In conclusion, the combination of weight-bearing training and MsAb have a greater positive effect on bone than treatment with either MsAb or weight-bearing training alone, suggesting that resistance training in combination with MSTN antagonists could be an effective approach for improving bone health and reducing osteoporosis risk.

The epigenetically active small chemical N-methyl pyrrolidone (NMP) prevents estrogen depletion induced osteoporosis

Currently, there are several treatments for osteoporosis however; they all display some sort of limitation and/or side effects making the need for new treatments imperative. We have previously demonstrated that NMP is a bioactive drug which enhances bone regeneration in vivo and acts as an enhancer of bone morphogenetic protein (BMP) in vitro. NMP also inhibits osteoclast differentiation and attenuates bone resorption.In the present study, we tested NMP as a bromodomain inhibitor and for osteoporosis prevention on ovariectomized (OVX) induced rats while treated systemically with NMP. Female Sprague–Dawley rats were ovariectomized and weekly NMP treatment was administrated 1week after surgery for 15weeks. Bone parameters and related serum biomarkers were analyzed. 15weeks of NMP treatment decreased ovariectomy-induced gained weight in average by 43% and improved bone mineral density (BMD) and bone volume over total volume (BV/TV) in rat femur on average by 25% and 41% respectively. Moreover, mineral apposition rate and bone biomarkers of bone turnover in the treatment group were at similar levels with those of the Sham group.Due to the function of NMP as a low affinity bromodomain inhibitor and its mechanism of action involving osteoblasts/osteoclasts balance and inhibitory effect on inflammatory cytokines, NMP is a promising therapeutic compound for the prevention of osteoporosis.

Effects of Single versus Hypofractionated Focused Radiation Therapy on Vertebral Structure and Biomechanical Integrity

Introduction Stereotactic radiosurgery has shown great promise in the treatment of metastatic lesions within the spine. However, recent clinical studies have indicated that the procedure may increase the risk of developing vertebral compression fractions, particularly in osteoporotic patients (Rose et al, 2009. J Clinical Onc. 27(29):5075; Boehling et al, 2012. J Neurosurg Spine. 16:379). There is thus a critical need for research examining the effects of focused radiation on bone quality and mechanical properties. We have developed a rabbit model which enables the analysis of the effects of focused radiation on vertebral osteonecrosis, structure, and biomechanical integrity. Using this model, we are testing the hypothesis that fractionation of radiation dosing can reduce radiation osteonecrosis and preserve structural and biomechanical integrity of the spine. Material and Methods The L5 vertebral body of New Zealand White (NZW) rabbits was treated, under computerized tomography (CT) guidance, with either a single 24 Gy dose of radiation or three fractionated doses over 3 consecutive days of 8 Gy radiation via the small animal radiation research platform (SARRP) (Wong et al, 2008. Int J Radiat Oncol Biol Phys. 71(5): 1591). Effects of radiation treatment on L2, L4, L5, and L6 vertebral osteonecrosis, structure, and biomechanical integrity were evaluated 6 months postirradiation via high-resolution CT imaging (Skyscan, Bruker, Belgium), histology, and nondestructive biomechanical compression testing and were compared with nonirradiated controls. Vertebral bone volume over total volume (BV/TV), trabecular thickness (Tb.Th.), and trabecular spacing (TB.Sp) were evaluated from CT images via CTAn software (Bruker, Belgium). Result/Conclusion: Results till date suggest that a localized single dose of 24 Gy radiation leads to loss of vertebral bone volume and trabecular number and a subsequent increase in trabecular spacing. Similarly, hypofractionation of the radiation dose (3 × 8 Gy) leads to reduced trabecular number and increased trabecular spacing, yet preserves normalized bone volume. Whether these changes in bone morphology translate into reduced mechanical integrity is currently under analysis. Future work will utilize this model to evaluate the efficacy of various therapies, such as teriparatide (PTH [1–34]), in the prevention of radiation-induced osteonecrosis.

Locally Administrated Perindopril Improves Healing in an Ovariectomized Rat Tibial Osteotomy Model

Angiotensin-converting enzyme inhibitors are widely prescribed to regulate blood pressure. High doses of orally administered perindopril have previously been shown to improve fracture healing in a mouse femur fracture model. In this study, perindopril was administered directly to the fracture area with the goal of stimulating fracture repair. Three months after being ovariectomized (OVX), tibial fractures were produced in Sprague–Dawley rats and subsequently stabilized with intramedullary wires. Perindopril (0.4 mg/kg/day) was injected locally at the fractured site for a treatment period of 7 days. Vehicle reagent was used as a control. Callus quality was evaluated at 2 and 4 weeks post-fracture. Compared with the vehicle group, perindopril treatment significantly increased bone formation, increased biomechanical strength, and improved microstructural parameters of the callus. Newly woven bone was arranged more tightly and regularly at 4 weeks post-fracture. The ultimate load increased by 66.1 and 76.9% (p<0.01), and the bone volume over total volume (BV/TV) increased by 29.9% and 24.3% (p<0.01) at 2 and 4 weeks post-fracture, respectively. These findings suggest that local treatment with perindopril could promote fracture healing in ovariectomized rats.

Local bone enhancement fuzzy clustering for segmentation of MR trabecular bone images

Segmentation of trabecular bone from magnetic resonance (MR) images is a challenging task due to spatial resolution limitations, signal-to-noise ratio constraints, and signal intensity inhomogeneities. This article examines an alternative approach to trabecular bone segmentation using partial membership segmentation termed fuzzy C-means clustering incorporating local second order features for bone enhancement (BE-FCM) at multiple scales. This approach is meant to allow for a soft segmentation that accounts for partial volume effects while suppressing the influence of noise. A soft segmentation method was developed and evaluated on three different sets of data; interscan reproducibility was evaluated on six test-retest in vivo MR scans of the proximal femur, correlation between MR and HR-pQCT measurements was evaluated on 49 in vivo scans from the distal tibia, and the potential for fracture discrimination was evaluated using MR scans of calcaneus specimens from 15 participants with and 15 participants without vertebral fracture. The algorithm was compared to fuzzy clustering using the intensity as the only feature (I-FCM) and a dual thresholding algorithm. The metric evaluated was bone volume over total volume (BV/TV) within user-defined regions of interest. BE-FCM had a higher interscan reproducibility (rms CV: 2.0%) compared to I-FCM (5.6%) and thresholding (4.2%), and expressed higher correlation to HR-pQCT data (r = 0.79, p < 10(-11)) compared to I-FCM (r = 0.74, p < 10(-8)) and thresholding (r = 0.70, p < 10(-6)). BE-FCM was also the method that was best able to differentiate between a control and a vertebral fracture group at a 95% significance level. The results suggest that trabecular bone segmentation by BE-FCM can provide a precise BV/TV measurement that is sensitive to pathology. The segmentation method may become useful in MR imaging-based quantification of bone microarchitecture.