Introduction. Forelimb and tail amputations of 3-week-old C57BL/6 mice are known to yield spinal curves similar to adolescent idiopathic scoliosis (AIS). Our previous work showed that tamoxifen produces a significant decrease in severity of these curves. Vertebral osteoporosis was thought to be related to AIS. Interestingly, a histological pilot study has shown that scoliotic mice given tamoxifen were less osteoporotic than were controls. Raloxifene is an oestrogen receptor modulator (SERM) similar to tamoxifen with a more specific effect on bone and is commonly used to treat osteoporosis. We aimed to study and compare the effects of tamoxifen and raloxifene on the rate and magnitude of scoliosis on a C57BL/6
To investigate temporal changes in synovial lymphatic system (SLS) drainage function after Anterior cruciate ligament (ACL) injury, a non-invasive ACL rupture model was used to induce the PTOA phenotype without altering the SLS structure. We have created a non-invasive ACL rupture model in the right knee (single overload impact) of 12- week-old C57bl/6 male mice to mimic the ACL rupture-induced PTOA development. 70 kDa-TxRedDextran were injected into the right knee of the mice at 0, 1, 2, and 4 wks post modeling (n=5/group), and the fluorescence signal distribution and intensity were measured by the IVIS system at 1 and 6 hrs post-injection. After 24 hrs, the drainage lymph nodes and whole knee joint were harvested and subjected to ex vivo IVIS imaging and immunofluorescence detection respectively. Manual ACL rupture was induced by 12N overloaded force and validated by a front drawer test. Intraarticular clearance of TxRed-Dextran detected by the IVIS was significantly reduced at 1, and 2 wks at a level of 43% and 55% respectively but was not significantly different from baseline levels at 4 wks (89%). TxRed-Dextran signal in draining lymph nodes was significantly reduced at 1 week at the level of but not for 2 and 4 wks compared to baseline levels (week 1–29%, week 2–50%, week 4–94%). TxRed-Dextran particle was significantly enriched in the synovium at 1, 2 wks but was not significantly different from baseline levels at 4 wks rupture-post ACL rupture (Particle numbers: Sham Ctrl-34 ±14, week 1, 113 ± 17; week 2, 89 ± 13; week 4, 46 ± 18; mean ± SD). We observed the drainage function of SLS significantly decreased at 1 and 2 wks after the ACL rupture, and was slowly restored at 4 wks post-injury in a non-invasive ACL rupture model. Early impairment of SLS drainage function may lead to accumulation of inflammatory factors and promote PTOA progression.
Mesenchymal stem cells (MSCs) are usually cultured in a normoxic atmosphere (21%) in vitro, while the oxygen concentrations in human tissues and organs are 1% to 10% when the cells are transplanted in vivo. However, the impact of hypoxia on MSCs has not been deeply studied, especially its translational application. In the present study, we investigated the characterizations of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in hypoxic (1%) and normoxic (21%) atmospheres with a long-term culture from primary to 30 generations, respectively. The comparison between both atmospheres systematically analyzed the biological functions of MSCs, mainly including stemness maintenance, immune regulation, and resistance to chondrocyte apoptosis, and studied their joint function and anti-inflammatory effects in osteoarthritis (OA) rats constructed by collagenase II.Aims
Methods
For patients who took joint replacement, one of the complications, aseptic joint loosening, could cause a high risk of revision surgery. Studies have shown that MSCs have the ability of homing and differentiating, and also have highly effective immune regulation and anti-inflammatory effects. However, few studies had focused on the stem cells in preventing the occurrence and development of aseptic loosening. In this research, we aimed to clarify whether human umbilical cord mesenchymal stem cells could inhibited the aseptic joint loosening caused by wear particles. A Cranial osteolysis
Digital Ventilated Cages (DVC) offer an innovative technology to obtain accurate movement data from a single mouse over time [1]. Thus, they could be used to determine the occurrence of a tendon damage event as well as inform on tissue regeneration [2,3]. Therefore, using the mouse model of tendon experimental damage, in this study it has been tested whether the recovery of tissue microarchitecture and of extracellular matrix (ECM) correlates with the motion data collected through this technology.
Based on Ilizarov's law of tension-stress principle, distraction histogenesis technique has been widely applied in orthopaedic surgery for decades. Derived from this technique, cranial bone transport technique was mainly used for treating cranial deformities and calvarial defects. Recent studies reported that there are dense short vascular connections between skull marrow and meninges for immune cells trafficking, highlighting complex and tight association between skull and brain. Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia without effective therapy. Meningeal lymphatics have been recognized as an important mediator in neurological diseases. The augmentation of meningeal lymphatic drainage might be a promising therapeutic target for AD. Our proof-of-concept study has indicated that cranial bone transport can promote ischemic stroke recovery via modulating meningeal lymphatic drainage function, providing a rationale for treating AD using cranial bone maneuver (CBM). This study aims to investigate the effects of CBM on AD and to further explore the potential mechanisms. Transgenic 5xFAD
Summary Statement. In this study, we observed that MR16-1, an interleukin-6 inhibitor, recovered phosphatidylcholine containing docosahexaenoic acid at the injury site after spinal cord injury in
Although autografts represent the gold standard for anterior cruciate ligament (ACL) reconstruction, tissue-engineered ACLs provide a prospect to minimize donor site morbidity and limited graft availability. This given study characterizes the ligamentogenesis in embroidered poly(L-lactide-co-ε-caprolactone) (P(LA-CL)) / polylactic acid (PLA) constructs using a dynamic nude
Lumbar diseases have become a major problem affecting human health worldwide. Conservative treatment of lumbar diseases is difficult to achieve ideal results, and surgical treatment of trauma, complications, it is imperative to develop a new treatment method. This study aims to explore the regulatory mechanism of cartilage endplate ossification caused by abnormal stress, and design intervention targets for this mechanism, so as to provide theoretical reference for the prevention and treatment of lumbar degeneration. In vivo, we constructed spinal instability
Segmental bone transport (SBT) with an external fixator has become a standard method for treatment of large bone defect. However, a long time-application of devices can be very troublesome and complications such as nonunion is sometimes seen at docking site. Although there have been several studies on SBT with large animal models, they were unsuitable for conducting drug application to improve SBT. The purpose of this study was to establish a bone transport
Scar tissue formation between nerve and surrounding muscle is one of the most undesired occurrence in nerve surgery In order to prevent scar tissue apposition after surgery, a lot of biocompatible products have been developed and tested first of all on animal models and then in surgical practice. we tested the efficacy of a CMC-PEO gel in reduction of perineural scar tissue formation in a
Cancer associated bone pain (CIBP) is a common event in patients with advanced disease with bone metastases (BM), significantly impairing their quality of life. Treatment options are limited and mainly based on the use of opioids with unacceptable side effects. Local acidosis is a well-known cause of pain since it directly stimulates nociceptors that express acid-sensing ion channels and densely innervate bone. In BM, local acidosis derives from osteoclast bone resorption activity and from the acidification by glycolytic tumor cells. Here we speculated that the pH lowering of intratumoral interstitial fluid also promotes nociceptors sensitization and hyperalgesia through the activation of cells of mesenchymal origin in BM microenvironment that might release inflammatory and nociceptive mediators. As a model of breast cancer that can metastatise to the bone we used MDA-MB-231 (MDA), and a subclone with a higher tendency to form osteolytic BM (bmMDA). We evaluated the basal expression of proton pumps/ion transporters by Real-Time PCR (Q-RT-PCR). To evaluate the effect of extracellular acidosis on mesenchymal tumor-associated stroma, we used human osteoblast primary cultures from healthy donors and cancer-associated fibroblasts isolated with specific immunobeads from the tumor biopsies of patient with BM. We exposed the cells to pH 6.8 medium at different time points (between 3 to 24 hours). After the short-term incubation with acidosis, for the expression of and acid-sensing ion channels, inflammatory cytokines and nociceptive mediators that can produce hyperalgesia, we used both a wide screening through a deep-sequencing approach and Q-RT-PCR, and ELISA. Xenograft for osteolytic BM induced by intratibial injection of bmMDA were treated with Omeprazole and monitored for CIBP through several cognitive tests. We found a significantly higher extracellular proton efflux and expression of proton pumps/ion transporters associated with the acid-base balance, the monocarboxylate transporter 4 (MCT4), the carbonic anhydrase (CA9), and the vacuolar ATPase (V-ATPase) V. 1. G. 1. subunit, and V. 0. c subunitin bmMDA, a subclone that is prone to form BM in respect to the parental cell line MDA-MB-231. In mesenchymal stromal cells, osteoblasts and cancer-associated fibroblasts, the incubation with pH 6.8 induced the expression of the achid-sensing ion channels AISC3/ACCN3 and AICS4/ACCN4, as well as of the nociceptive modulators nerve growth factor (NGF), Brain-derived neurotrophic factor (BDNF), and of the inflammatory cytokines interleukin 6 (IL6) and 8 (IL8), and Chemokine (C-C motif) ligand 5 (CCL5). Furthermore, the targeting of V0c subunit to inhibit intratumoral acidification significantly reduced CIBP in
Introduction. Previous work has shown that C57BL/6 mice develop scoliosis when rendered bipedal. Our previous work suggested that tamoxifen (TMX) might change the natural course of scoliosis when administered before scoliotic curves develop. We analysed whether the incidence of scoliosis or the magnitude of curves may be decreased by the administration of tamoxifen after curves are observed. Methods. 20 female, 3-week-old C57BL/6 mice underwent amputations of forelimbs and tails at 3 weeks, 18 of which were included in analyses. Posteroanterior scoliosis radiographs were obtained at week 20, and scoliotic curves were recorded. After week 20, all mice received 10 mg TMX per L of daily water supply for 20 weeks. The course of deformities in this group (week 20 group) was compared with that of previous study groups (receiving TMX from week 3; week 3 group). Results. At week 20, overall, upper thoracic (UT), thoraco-lumbar (TL), and double curve scoliosis rates were similar in both groups, but the thoracic (T) scoliosis rate was lower in the week 3 group. At week 40, although T, TL, and double curve scoliosis rates were similar between groups, overall rate and the rates of UT scoliosis were significantly lower in week 3 group (table). We recorded no significant change of curve rates in week 20 group apart from the TL rate, which showed a significant increase (p=0·025). Mean Cobb angles were similar in both study groups (p>0·05) at 20 and 40 weeks. Conclusions. This study has shown that TMX administered after scoliotic changes are observed seems to be less effective compared with prior TMX protocol in C57BL/6
Summary. In this study, we challenged the current paradigm of human Mesenchymal Stem Cells survival, which assigned a pivotal role to oxygen, by testing the hypothesis that exogenous glucose may be key to their survival. Introduction. The survival of human mesenchymal stem cells (hMSCs) has elicited a great deal of interest, because it is relevant to the efficacy of engineered tissues. However, to date, hMSCs have not met this promise, in part due to the high death rate of cells upon transplantation. In this study, we challenged the current paradigm of hMSC survival, which assigned a pivotal role to oxygen, by testing the hypothesis that exogenous glucose may be key to hMSC survival. Materials and methods. In vitro model of ischemia 2.10. 4. hMSCs from five donors, were seeded into individual wells of a 24-well plate, cultured overnight, washed twice with PBS and then maintained in hypoxia (0.1% oxygen) under serum (FBS) free αMEM medium in either the absence or in the presence (1 or 5 g/L) of glucose for 21 days. In vitro Cell viability: To assess the role of glucose on hMSCs viability, cells were cultured under hypoxia in the absence or in the presence of glucose (1 and 5g/L), At days 0, 3, 7, 14 and 21, cell viability was evaluated by flow cytometry and ATP content per cell quantified. In vivo effect of glucose supply on hMSCs viability. 3.10. 5. eGFG-luc hMSCs were seeded on a cylindrical AN-69 scaffolds. At the time of implantation, 100 µl of hyaluronic acide (HA) (2%) containing either 0g/L (negative control) or 10g/L of glucose was gently injected inside the construct. Cell- constructs were implanted subcutaneously in eight week-old mice (2 per animal) and were imaged by bioluminescence imaging (BLI) at day 1, 4, 7 and 14 until sacrifice. Results. hMSCs were able to survive and to maintain their ATP content 21 days under sustained hypoxia providing that they were cultured in the presence of a sufficient glucose supply (i.e. 5g/L). In contrast, hMSCs cultured without or with 1g/L of glucose failed to survive. These results established that glucose depletion but not sustained hypoxia affected cell survival. In vivo results showed a striking increase of cell viability in cell constructs loaded with glucose. At day 14, a five-fold increase in cell number was observed in cell constructs loaded with glucose when compared to the control cell constructs without glucose. Discussion. The present study challenge the current paradigm that gives a pivotal role to oxygen on hMSCs massive cell death. By using an in vitro model of hypoxia/ischemia, we demonstrated that in the presence of sufficient glucose, hMSCs were able to survive 21 days under sustained hypoxia. Most importantly, an appropriate glucose supply strongly increases cell viability of hMSCs implanted subcutaneously in a
Osteoarthritis (OA) is a prevalent joint disorder with inflammatory response and cartilage deterioration as its main features. Dihydrocaffeic acid (DHCA), a bioactive component extracted from natural plant ( In vitro, interleukin-1 beta (IL-1β) was used to establish the mice OA chondrocytes. Cell counting kit-8 evaluated chondrocyte viability. Western blotting analyzed the expression levels of collagen II, aggrecan, SOX9, inducible nitric oxide synthase (iNOS), IL-6, matrix metalloproteinases (MMPs: MMP1, MMP3, and MMP13), and signalling molecules associated with nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Immunofluorescence analysis assessed the expression of aggrecan, collagen II, MMP13, and p-P65. In vivo, a destabilized medial meniscus (DMM) surgery was used to induce mice OA knee joints. After injection of DHCA or a vehicle into the injured joints, histological staining gauged the severity of cartilage damage.Aims
Methods
There is an increasing concern of osteoporotic fractures in the ageing population. Low-magnitude high-frequency vibration (LMHFV) was shown to significantly enhance osteoporotic fracture healing through alteration of osteocyte lacuno-canalicular network (LCN). Dentin matrix protein 1 (DMP1) in osteocytes is known to be responsible for maintaining the LCN and mineralization. This study aimed to investigate the role of osteocyte-specific DMP1 during osteoporotic fracture healing augmented by LMHFV. A metaphyseal fracture was created in the distal femur of ovariectomy-induced osteoporotic Sprague Dawley rats. Rats were randomized to five different groups: 1) DMP1 knockdown (KD), 2) DMP1 KD + vibration (VT), 3) Scramble + VT, 4) VT, and 5) control (CT), where KD was performed by injection of short hairpin RNA (shRNA) into marrow cavity; vibration treatment was conducted at 35 Hz, 0.3 g; 20 minutes/day, five days/week). Assessments included radiography, micro-CT, dynamic histomorphometry and immunohistochemistry on DMP1, sclerostin, E11, and fibroblast growth factor 23 (FGF23). In vitro, murine long bone osteocyte-Y4 (MLO-Y4) osteocyte-like cells were randomized as in vivo groupings. DMP1 KD was performed by transfecting cells with shRNA plasmid. Assessments included immunocytochemistry on osteocyte-specific markers as above, and mineralized nodule staining.Aims
Methods
Mechanical stimulation is a key factor in the development and healing of tendon-bone insertion. Treadmill training is an important rehabilitation treatment. This study aims to investigate the benefits of treadmill training initiated on postoperative day 7 for tendon-bone insertion healing. A tendon-bone insertion injury healing model was established in 92 C57BL/6 male mice. All mice were divided into control and training groups by random digital table method. The control group mice had full free activity in the cage, and the training group mice started the treadmill training on postoperative day 7. The quality of tendon-bone insertion healing was evaluated by histology, immunohistochemistry, reverse transcription quantitative polymerase chain reaction, Western blotting, micro-CT, micro-MRI, open field tests, and CatWalk gait and biomechanical assessments.Aims
Methods
Osteoarthritis (OA) is a common degenerative joint disease characterized by chronic inflammatory articular cartilage degradation. Long noncoding RNAs (lncRNAs) have been previously indicated to play an important role in inflammation-related diseases. Herein, the current study set out to explore the involvement of lncRNA H19 in OA. Firstly, OA mouse models and interleukin (IL)-1β-induced mouse chondrocytes were established. Expression patterns of IL-38 were determined in the synovial fluid and cartilage tissues from OA patients. Furthermore, the targeting relationship between lncRNA H19, tumour protein p53 (TP53), and IL-38 was determined by means of dual-luciferase reporter gene, chromatin immunoprecipitation, and RNA immunoprecipitation assays. Subsequent to gain- and loss-of-function assays, the levels of cartilage damage and proinflammatory factors were further detected using safranin O-fast green staining and enzyme-linked immunosorbent assay (ELISA) in vivo, respectively, while chondrocyte apoptosis was measured using Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling (TUNEL) in vitro.Aims
Methods
Osteoarthritis (OA) is a highly prevalent degenerative joint disorder characterized by joint pain and physical disability. Aberrant subchondral bone induces pathological changes and is a major source of pain in OA. In the subchondral bone, which is highly innervated, nerves have dual roles in pain sensation and bone homeostasis regulation. The interaction between peripheral nerves and target cells in the subchondral bone, and the interplay between the sensory and sympathetic nervous systems, allow peripheral nerves to regulate subchondral bone homeostasis. Alterations in peripheral innervation and local transmitters are closely related to changes in nociception and subchondral bone homeostasis, and affect the progression of OA. Recent literature has substantially expanded our understanding of the physiological and pathological distribution and function of specific subtypes of neurones in bone. This review summarizes the types and distribution of nerves detected in the tibial subchondral bone, their cellular and molecular interactions with bone cells that regulate subchondral bone homeostasis, and their role in OA pain. A comprehensive understanding and further investigation of the functions of peripheral innervation in the subchondral bone will help to develop novel therapeutic approaches to effectively prevent OA, and alleviate OA pain. Cite this article:
The association of auraptene (AUR), a 7-geranyloxycoumarin, on osteoporosis and its potential pathway was predicted by network pharmacology and confirmed in experimental osteoporotic mice. The network of AUR was constructed and a potential pathway predicted by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment. Female ovariectomized (OVX) Institute of Cancer Research mice were intraperitoneally injected with 0.01, 0.1, and 1 mM AUR for four weeks. The bone mineral density (BMD) level was measured by dual-energy X-ray absorptiometry. The bone microstructure was determined by histomorphological changes in the femora. In addition, biochemical analysis of the serum and assessment of the messenger RNA (mRNA) levels of osteoclastic markers were performed.Aims
Methods