3D-printed hydrogel particles containing PRP laden with TDSCs promote tendon repair in a rat model of tendinopathy.

Long-term chronic inflammation after Achilles tendon injury is critical for tendinopathy. Platelet-rich plasma (PRP) injection, which is a common method for treating tendinopathy, has positive effects on tendon repair. In addition, tendon-derived stem cells (TDSCs), which are stem cells located in tendons, play a major role in maintaining tissue homeostasis and postinjury repair. In this study, injectable gelatine methacryloyl (GelMA) microparticles containing PRP laden with TDSCs (PRP-TDSC-GM) were prepared by a projection-based 3D bioprinting technique. Our results showed that PRP-TDSC-GM could promote tendon differentiation in TDSCs and reduce the inflammatory response by downregulating the PI3K-AKT pathway, thus promoting the structural and functional repair of tendons in vivo.

Non-Invasive Muscular Atrophy Causes Evaluation for Limb Fracture Based on Flexible Surface Electromyography System.

Muscular atrophy after limb fracture is a frequently occurring complication with multiple causes. Different treatments and targeted rehabilitation procedures should be carried out based on the causes. However, bedside evaluation methods are invasive in clinical practice nowadays, lacking reliable non-invasive methods. In this study, we propose a non-invasive flexible surface electromyography system with machine learning algorithms to distinguish nerve-injury and limb immobilization-related atrophy. First, a flexible surface electromyography sensor was designed and verified by in vitro tests for its robustness and flexibility. Then, in vivo tests on rats proved the reliability compared with the traditional invasive diagnosis method. Finally, this system was applied for the diagnosis of muscular atrophy in 10 patients. The flexible surface electromyography sensor can achieve a max strain of 12.0%, which ensures close contact with the skin. The in vivo tests on rats show great comparability with the traditional invasive diagnosis method. It can achieve a high specificity of 95.28% and sensitivity of 98.98%. Application on patients reaches a relatively high specificity of 89.44% and sensitivity of 91.94%. The proposed painless surface electromyography system can be an easy and accurate supplementary for bedside muscular atrophy causes evaluation, holding excellent contact with the body.

Stachydrine hydrochloride inhibits osteoclastogenesis by regulating the NF-κB and p38 signaling pathways to alleviate postmenopausal osteoporosis.

Osteoporosis is a common skeletal disorder characterized by low bone mass, defective bone microstructure, and increased risk of fracture. It's well known that excessive activation of osteoclasts plays a vital role in the pathogenesis of osteoporosis. Thus, inhibition of osteoclast formation and function might be a proving strategy for osteoporosis. In our study, for the first time we explored the effect of Stachydrine Hydrochloride in the treatment of osteoporosis. We demonstrated that SH markedly inhibited osteoclastogenesis and osteoclast function in vitro and effectively decrease bone resorption in vivo. These finding were further supported by changes in the NF-κB and p38 signaling pathways, which are classical downstream pathways of RANKL-mediated osteoclastogensis. Collectively, these data suggest the possible future use of SH to protect against bone loss in the treatment of osteoporosis.

Causal relationship of serum nutritional factors with osteoarthritis: a Mendelian randomization study.

OBJECTIVES: OA is the most common form of arthritis worldwide and has a major impact on the quality of life among the older population. This study aimed at determining the potential causal effects of several serum nutritional factors on OA. METHODS: A total of seven serum nutritional factors were identified from genome-wide association studies. Summary statistics for OA were obtained from UK Biobank (194 153 for women and 166 988 for men) and a large genome-wide association studies meta-analysis based on the European population (455 221, 393 873 and 403 124 for overall, hip and knee OA, respectively). Two-sample Mendelian randomization approach was used to estimate the causal association between the selected nutritional factors and the risk of OA. RESULTS: The Mendelian randomization analyses suggested that serum calcium levels were inversely associated with overall OA (95% CI, 0.595, 0.850), hip OA (95% CI, 0.352, 0.799) and knee OA (95% CI, 0.461, 0.901). Serum retinol levels were also inversely associated with hip OA (95% CI, 0.257, 0.778). Moreover, sex-specific associations were observed between serum calcium levels (95% CI, 0.936, 0.998), iron levels (95% CI, 1.000, 1.012), selenium levels (95% CI, 0.923, 0.999) and OA in women. CONCLUSION: In this study, an inverse causal association between serum calcium levels and OA was established. Serum retinol levels were inversely associated with hip OA. In addition, we provide evidence for the causal effect of serum calcium, iron and selenium on the risk of OA in women.

Senkyunolide H attenuates osteoclastogenesis and postmenopausal osteoporosis by regulating the NF-κB, JNK and ERK signaling pathways.

Osteoporosis is a common disease characterized by reduced bone mineral density and impaired bone strength and is currently one of the leading causes of fracture and morbidity among the elderly worldwide. The pathological generation of osteoclasts is an important event in the development of extensive bone resorption. Thus, the development of a drug that targets osteoclasts may be beneficial in treating osteoporosis. Accordingly, in this study, we investigated the effects of senkyunolide H (SNH), an active component extracted from ligusticum chuanxiong Hort, on osteoporosis through a series of in vivo and in vitro experiments. First, we found that SNH had a therapeutic effect in ovariectomized mice by inhibiting osteoclast formation. Then, the inhibitory effect on osteoclast differentiation was confirmed in vitro. Further western blotting analysis revealed that SNH downregulated receptor activator of nuclear factor (NF)-κΒ ligand-induced NF-κB signaling activation, c-Jun N-terminal kinase (JNK) in the mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK) signaling pathway. These data indicated that SNH may be a potential treatment for postmenopausal osteoporosis.

Tomatidine suppresses osteoclastogenesis and mitigates estrogen deficiency-induced bone mass loss by modulating TRAF6-mediated signaling.

Postmenopausal osteoporosis is initiated by estrogen withdrawal and is characterized mainly by overactivated osteoclastic bone resorption. Targeting TNF receptor-associated factor 6 (TRAF6) or its downstream signaling pathways to modulate osteoclast formation and function is an appealing strategy for osteoclast-related disorders. In the present study, we determined the effect of tomatidine, a steroidal alkaloid derived from Solanaceae, on the formation and function of receptor activator of NF-κB (RANK) ligand-induced osteoclasts and the underlying mechanism. Tomatidine inhibited osteoclast formation in a dose-dependent manner and decreased the expression of osteoclast marker genes. Actin ring formation and osteoclastic bone resorption were attenuated in the presence of tomatidine in vitro. Eight weeks after ovariectomy, tomatidine prevented estrogen deficiency-induced bone loss and restored the mechanical properties of the femur. At the molecular level, tomatidine abrogated phosphorylation of c-Jun N-terminal kinase (JNK)/p38, NF-κB, and protein kinase B (Akt) pathway proteins by suppressing RANK expression, inhibiting the binding of TRAF6 to RANK, and downregulating the osteoclastogenesis marker-related protein expression. In summary, these data demonstrated that tomatidine attenuated osteoclast formation and function by modulating multiple TRAF6-mediated pathways. Therefore, tomatidine could be a novel candidate for the treatment of osteoclast-related disorders, including osteoporosis.-Hu, B., Sun, X., Yang, Y., Ying, Z., Meng, J., Zhou, C., Jiang, G., Li, S., Wu, F., Zhao, X., Zhu, H., Wu, H., Cai, X., Shi, Z., Yan, S. Tomatidine suppresses osteoclastogenesis and mitigates estrogen deficiency-induced bone mass loss by modulating TRAF6-mediated signaling.

Stachydrine prevents LPS-induced bone loss by inhibiting osteoclastogenesis via NF-κB and Akt signalling.

Osteoclast overactivation-induced imbalance in bone remodelling leads to pathological bone destruction, which is a characteristic of many osteolytic diseases such as rheumatoid arthritis, osteoporosis, periprosthetic osteolysis and periodontitis. Natural compounds that suppress osteoclast formation and function have therapeutic potential for treating these diseases. Stachydrine (STA) is a bioactive alkaloid isolated from Leonurus heterophyllus Sweet and possesses antioxidant, anti-inflammatory, anticancer and cardioprotective properties. However, its effects on osteoclast formation and function have been rarely described. In the present study, we found that STA suppressed receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast formation and bone resorption, and reduced osteoclast-related gene expression in vitro. Mechanistically, STA inhibited RANKL-induced activation of NF-κB and Akt signalling, thus suppressing nuclear factor of activated T cells c1 induction and nuclear translocation. In addition, STA alleviated bone loss and reduced osteoclast number in a murine model of LPS-induced inflammatory bone loss. STA also inhibited the activities of NF-κB and NFATc1 in vivo. Together, these results suggest that STA effectively inhibits osteoclastogenesis both in vitro and in vivo and therefore is a potential option for treating osteoclast-related diseases.

Efficacy of Laminoplasty in Patients with Cervical Kyphosis.

BACKGROUND The efficacy of laminoplasty in patients with cervical kyphosis is controversial. The purpose of this study was to investigate the impact of the initial pathogenesis on the clinical outcomes of laminoplasty in patients with cervical kyphosis. MATERIAL AND METHODS A total of 137 patients with cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL) underwent laminoplasty from April 2013 to May 2015. The patients were divided into the following 4 groups: lordosis with CSM (LC), kyphosis with CSM (KC), lordosis with OPLL (LO), and kyphosis with OPLL (KO). The clinical outcome measures included the visual analogue scale (VAS) and modified Japanese Orthopedic Association (mJOA) scores, the range of motion (ROM), and the cervical global angle (CGA). RESULTS The mean VAS and mJOA scores improved significantly in all groups after surgery. The changes in VAS and mJOA scores were significantly smaller, and the JOA recovery rate was significantly lower, in the KC group than in the LC and KO groups. The mean change in the CGA was greatest in the KC group (>8° towards kyphosis). The preoperative ROM was negatively correlated with the change in CGA and the JOA recovery rate in the KO and KC groups. CONCLUSIONS We found that laminoplasty is suitable for patients with cervical lordosis and those with mild cervical kyphosis and OPLL, but is not recommended for patients with kyphosis and CSM, particularly those with a large ROM preoperatively.

The Plasticity of Brain Gray Matter and White Matter following Lower Limb Amputation.

Accumulating evidence has indicated that amputation induces functional reorganization in the sensory and motor cortices. However, the extent of structural changes after lower limb amputation in patients without phantom pain remains uncertain. We studied 17 adult patients with right lower limb amputation and 18 healthy control subjects using T1-weighted magnetic resonance imaging and diffusion tensor imaging. Cortical thickness and fractional anisotropy (FA) of white matter (WM) were investigated. In amputees, a thinning trend was seen in the left premotor cortex (PMC). Smaller clusters were also noted in the visual-to-motor regions. In addition, the amputees also exhibited a decreased FA in the right superior corona radiata and WM regions underlying the right temporal lobe and left PMC. Fiber tractography from these WM regions showed microstructural changes in the commissural fibers connecting the bilateral premotor cortices, compatible with the hypothesis that amputation can lead to a change in interhemispheric interactions. Finally, the lower limb amputees also displayed significant FA reduction in the right inferior frontooccipital fasciculus, which is negatively correlated with the time since amputation. In conclusion, our findings indicate that the amputation of lower limb could induce changes in the cortical representation of the missing limb and the underlying WM connections.

Pogostone attenuates osteolysis in breast cancer by inhibiting the NF-kB and JNK signaling pathways of osteoclast.

AIMS: Breast cancer is the most prevalent cancer in females, and approximately 70 % of all patients have evidence of metastatic bone disease, which substantially affects the quality of life and survival rate of breast cancer patients. Osteoporosis has become a global public health problem, and the abnormal activation of osteoclasts is the key to the progression of osteoporosis and the key to both diseases lies in the osteoclasts. Effective drug treatments are lacking and there is an urgent need to explore new drugs. MATERIALS AND METHODS: We observed the effects of pogostone (PO) on osteoclast differentiation, bone resorption function and other indicators, and F-actin ring formation by using Trap staining, SEM and immunofluorescence, and further explored the targets of pogostone in regulating osteoclast differentiation and function using qPCR and Western Blot. In addition, we used CCK 8, Transwell, and flow cytometry to study the effects of pogostone on proliferation, invasion, migration, and apoptosis of MDA-MB-231 cells. Animal models were also constructed for in vivo validation. KEY FINDINGS: Pogostone inhibits osteoclast differentiation, bone resorption, formation of F-actin ring, and the expression of specific genes by attenuated NF-kB degradation and phosphorylation of JNK. In vitro, pogostone suppresses invasion of breast cancer cells, migration, and promotes their apoptosis. In mouse models, pogostone attenuated osteoclast formation and bone resorption, blocked breast cancer cells migration, and supprsed breast cancer-induced osteolysis and ovariectomized (OVX)-mediated osteoporosis. SIGNIFICANCE: These biological functions of pogostone make it a potential drug for treatment of breast cancer-associated bone metastasis in the future.

Association of SMC4 with prognosis and immune infiltration of sarcoma.

OBJECTIVE: This study was performed to explore the prognostic relevance of structural maintenance of chromosomes 4 (SMC4) in pan-cancer and explore the association between SMC4 and immune infiltration of sarcoma. RESULTS: Elevated expression of SMC4 was detected in cancer tissues compared to normal tissue, which was confirmed in synovial sarcoma tissues with immunohistochemistry (IHC). Additionally, higher expression of SMC4 was connected to worse outcomes of sarcoma, gastric cancer, breast cancer, liver cancer or ovarian cancer. Moreover, SMC4 was positively connected to immune cell infiltrates in sarcoma. In addition, infiltrating immune cell markers including monocyte, TAM, M1 and M2 presented different SMC4-associated immune infiltration patterns. CONCLUSION: The results from our study showed that SMC4 was positively related to the prognosis and immunological status of sarcoma. SMC4 could be a potential biomarker for prognosis and immune cell infiltrates in sarcoma. METHODS: Several databases including ONCOMINE, GEPIA, and Kaplan-Meier Plotter were adopted to explore the expression pattern of SMC4 in sarcoma, which was confirmed by IHC. The GEPIA and TIMER datasets were adopted to investigate the associations between SMC4 and prognosis in various cancers, especially in sarcoma.

Association of NCAP family genes with prognosis and immune infiltration of human sarcoma.

OBJECTIVE: This study was conducted to explore the correlation of NCAP family genes with expression, prognosis, and immune infiltration in human sarcoma. RESULTS: Compared with normal human tissues, six NCAP family genes were highly expressed in sarcoma tissues, and high expression of the six genes were significantly associated with the poor prognosis of sarcoma patients. The expression of NCAPs in sarcoma was significantly related to the low infiltration level of macrophages and CD4+ T cells. GO and KEGG enrichment analysis showed that NCAPs and their interacting genes were mainly enriched in organelle fission for biological processes (BP), spindle for cellular component (CC), tubulin binding for molecular function (MF), and 'Cell cycle' pathway. METHODS: We explored the expression of NCAP family members by ONCOMINE, and GEPIA databases. Additionally, the prognostic value of NCAP family genes in sarcoma was detected by Kaplan-Meier Plotter and GEPIA databases. Moreover, we explored the relationship between NCAP family gene expression level and immune infiltration using the TIMER database. Finally, we performed GO and KEGG analysis for NCAPs-related genes by DAVID database. CONCLUSION: The six members of NCAP gene family can be used as biomarkers to predict the prognosis of sarcoma. They were also correlated with the low immune infiltration in sarcoma.

Rejuvenation of tendon stem/progenitor cells for functional tendon regeneration through platelet-derived exosomes loaded with recombinant Yap1.

The regenerative capabilities including self-renewal, migration and differentiation potentials shift from the embryonic phase to the mature period of endogenous tendon stem/progenitor cells (TSPCs) characterize restricted functions and disabilities following tendon injuries. Recent studies have shown that tendon regeneration and repair rely on multiple specific transcription factors to maintain TSPCs characteristics and functions. Here, we demonstrate Yap, a Hippo pathway downstream effector, is associated with TSPCs phenotype and regenerative potentials through gene expression analysis of tendon development and repair process. Exosomes have been proven an efficient transport platform for drug delivery. In this study, purified exosomes derived from donor platelets are loaded with recombinant Yap1 protein (PLT-Exo-Yap1) via electroporation to promote the stemness and differentiation potentials of TSPCs in vitro. Programmed TSPCs with Yap1 import maintain stemness and functions after long-term passage in vitro. The increased oxidative stress levels of TSPCs are related to the phenotype changes in duplicative senescent processes. The results show that treatment with PLT-Exo-Yap1 significantly protects TSPCs against oxidative stressor-induced stemness loss and senescence-associated secretory phenotype (SASP) through the NF-κB signaling pathway. In addition, we fabricate an Exos-Yap1-functioned GelMA hydrogel with a parallel-aligned substrate structure to enhance TSPCs adhesion, promote cell stemness and force regenerative cells toward the tendon lineage for in vitro and in vivo tendon regeneration. The application of Exos-Yap1 functioned implant assists new tendon-like tissue formation with good mechanical properties and locomotor functions in a full-cut Achilles tendon defect model. Thus, PLT-Exo-Yap1-functionalized GelMA promotes the rejuvenation of TSPCs to facilitate functional tendon regeneration. STATEMENT OF SIGNIFICANCE: This is the first study to explore that the hippo pathway downstream effector Yap is involved in tendon aging and repair processes, and is associated with the regenerative capabilities of TSPCs. In this syudy, Platelet-derived exosomes (PLT-Exos) act as an appropriate carrier platform for the delivery of recombinant Yap1 into TSPCs to regulate Yap activity. Effective Yap1 delivery inhibit oxidative stress-induced senescence associated phenotype of TSPCs by blocking ROS-mediated NF-κb signaling pathway activation. This study emphasizes that combined application of biomimetic scaffolds and Yap1 loaded PLT-Exos can provide structural support and promote rejuvenation of resident cells to assist functional regeneration for Achilles tendon defect, and has the prospect of clinical setting.

GSTP1-mediated S-glutathionylation of Pik3r1 is a redox hub that inhibits osteoclastogenesis through regulating autophagic flux.

Glutathione S-transferase P1(GSTP1) is known for its transferase and detoxification activity. Based on disease-phenotype genetic associations, we found that GSTP1 might be associated with bone mineral density through Mendelian randomization analysis. Therefore, this study was performed both in vitro cellular and in vivo mouse model to determine how GSTP1 affects bone homeostasis. In our research, GSTP1 was revealed to upregulate the S-glutathionylation level of Pik3r1 through Cys498 and Cys670, thereby decreasing its phosphorylation, further controlling the alteration of autophagic flux via the Pik3r1-AKT-mTOR axis, and lastly altering osteoclast formation in vitro. In addition, knockdown and overexpression of GSTP1 in vivo also altered bone loss outcomes in the OVX mice model. In general, this study identified a new mechanism by which GSTP1 regulates osteoclastogenesis, and it is evident that the cell fate of osteoclasts is controlled by GSTP1-mediated S-glutathionylation via a redox-autophagy cascade.

Sandwich Biomimetic Scaffold Based Tendon Stem/Progenitor Cell Alignment in a 3D Microenvironment for Functional Tendon Regeneration.

Tendon injuries are some of the most commonly diagnosed musculoskeletal diseases. Tendon regeneration is sensitive to the topology of the substitute as it affects the cellular microenvironment and homeostasis. To bionic in vivo three-dimensional (3D) aligned microenvironment, an ordered 3D sandwich model was used to investigate the cell response in the tendon. First, high-resolution 3D printing provided parallel-grooved topographical cues on the hydrogel surface. Then the cells were seeded on its surface to acquire a 2D model. Afterward, an additional hydrogel coating layer was applied to the cells to create the 3D model. The interaction between cells and order structures in three-dimensions is yet to be explored. The study found that the tendon stem/progenitor cells (TSPCs) still maintain their ordering growth in the 3D model as in the 2D model. The study also found that the 3D-aligned TSPCs exhibited enhanced tenogenic differentiation through the PI3K-AKT signaling pathway and presented a less inflammatory phenotype than those in the 2D model. The in vivo implantation of such a 3D-aligned TSPC composite promoted tendon regeneration and mitigated heterotopic ossification in an Achilles defect model. These findings demonstrated that 3D-aligned TSPCs within a biomimetic topology environment are promising for functional tendon regeneration.

α-Mangostin inhibits LPS-induced bone resorption by restricting osteoclastogenesis via NF-κB and MAPK signaling.

BACKGROUND: Excessive osteoclast activation is an important cause of imbalanced bone remodeling that leads to pathological bone destruction. This is a clear feature of many osteolytic diseases such as rheumatoid arthritis, osteoporosis, and osteolysis around prostheses. Because many natural compounds have therapeutic potential for treating these diseases by suppressing osteoclast formation and function, we hypothesized that α-mangostin, a natural compound isolated from mangosteen, might be a promising treatment as it exhibits anti-inflammatory, anticancer, and cardioprotective effects. METHODS: We evaluated the therapeutic effect of α-mangostin on the processes of osteoclast formation and bone resorption. The receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) induces osteoclast formation in vitro, and potential pathways of α-mangostin to inhibit osteoclast differentiation and function were explored. A mouse model of lipopolysaccharide-induced calvarial osteolysis was established. Subsequently, micro-computed tomography and histological assays were used to evaluate the effect of α-mangostin in preventing inflammatory osteolysis. RESULTS: We found that α-mangostin could inhibit RANKL-induced osteoclastogenesis and reduced osteoclast-related gene expression in vitro. F-actin ring immunofluorescence and resorption pit assays indicated that α-mangostin also inhibited osteoclast functions. It achieved these effects by disrupting the activation of NF-κB/mitogen-activated protein kinase signaling pathways. Our in vivo data revealed that α-mangostin could protect mouse calvarial bone from osteolysis. CONCLUSIONS: Our findings demonstrate that α-mangostin can inhibit osteoclastogenesis both in vitro and in vivo and may be a potential option for treating osteoclast-related diseases.

The cervical sagittal curvature change in patients with or without PCSM after laminoplasty.

Objective: After laminoplasty, the cervical sagittal curvature of some patients tend to be lordotic, this phenomenon cannot be explained by the theory of laminoplasty, and the reason remains unknown. We explored the possible role played by pinching cervical spondylotic myelopathy (PCSM) in the cervical sagittal curvature change in patients after laminoplasty. Methods: From April 2017 to May 2019, we studied 122 patients undergoing laminoplasty with cervical spondylotic myelopathy (CSM). All patients were divided into Group A (anterior compression only, without PCSM) and Group B (both anterior and posterior compression, with PCSM). The visual analogue scale (VAS) was used to measure pain, and modified Japanese Orthopedic Association (mJOA) score was derived. The cervical global angle (CGA) and the range of cervical motion (ROM) were compared. The clinical and imaging results were compared between Group A and Group B. Results: After laminoplasty, both the mean VAS and mJOA scores improved significantly in Group A and Group B, the mJOA recovery rate of Group B was better than that of Group A (P < 0.05). The mean CGA and ROM decreased in Group A, but increased in Group B. MRI revealed that the ligamentum flavum of Group A was significantly thinner than that of Group B (P < 0.05). Conclusions: Because of the hypertrophic and folded ligamentum flavum compressing the dorsal spinal cord, patients with PCSM may maintain a compulsive kyphotic posture. After laminoplasty, the cervical sagittal curvature of these patients tend to be lordotic due to the release of dorsal spinal cord compression.

Comparative Effects of Exosomes and Ectosomes Isolated From Adipose-Derived Mesenchymal Stem Cells on Achilles Tendinopathy in a Rat Model.

BACKGROUND: Extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have gained momentum as a treatment for tendinopathy. Multiple studies have demonstrated significant differences in cargo composition between the 2 subtypes of MSC-EVs (ie, exosomes and ectosomes), which may result in different therapeutic effects. However, the effects of the 2 EV subtypes on tendinopathy have not yet been compared. PURPOSE: To compare the effects of adipose stem cell-derived exosomes (ASC-Exos) and ectosomes (ASC-Ectos) on Achilles tendinopathy. STUDY DESIGN: Controlled laboratory study. METHODS: Rats were administered collagenase injections to generate a model of Achilles tendinopathy. A week later, 36 rats were randomly assigned to 3 groups. In each group, Achilles tendons were injected with equal volumes of ASC-Exos, ASC-Ectos, or saline (12 legs/group). The healing outcomes were evaluated by magnetic resonance imaging, histology, immunohistochemistry, transmission electron microscopy, and biomechanical testing at 3 and 5 weeks after collagenase injection. RESULTS: At 3 and 5 weeks, the ASC-Exo group had better histological scores (P = .0036 and P = .0276, respectively), a lower fibril density (P < .0001 and P = .0310, respectively), and a larger collagen diameter (P = .0052 and P < .0001, respectively) than the ASC-Ecto group. At 5 weeks, the expression of collagen type 1 and CD206 in the ASC-Exo group was significantly higher than that in the ASC-Ecto group (P = .0025 and P = .0010, respectively). Regarding biomechanical testing, the ASC-Exo group showed higher failure load (P = .0005), tensile stress (P < .0001), and elastic modulus (P < .0001) than the ASC-Ecto group. CONCLUSION: ASC-Exos had more beneficial effects on tendon repair than ASC-Ectos in a rat model of Achilles tendinopathy. CLINICAL RELEVANCE: Administration of ASC-EVs may have the potential to treat Achilles tendinopathy, and delivery of ASC-Exos could provide additional benefits. It is necessary to compare the healing responses caused by different EV subtypes to further understand their effects on tendinopathy and to aid clinical decision making.

Punicalin Attenuates Breast Cancer-Associated Osteolysis by Inhibiting the NF-κB Signaling Pathway of Osteoclasts.

Background: Breast cancer bone metastasis and osteoporosis are both severe diseases that seriously threaten human health. These diseases are closely associated with osteolytic lesions. And osteoclasts are the key targets of this pathological process. Given the lack of effective preventive or treatment options against these diseases, the exploitation of new pharmacological agents is critically required. Method: We assessed the efficacy of punicalin on receptor activator of nuclear factor-κB ligand (RANKL)-mediated osteoclast formation, F-actin ring formation, gene expression, bone resorption, nuclear factor-κB (NF-κB) as well as on mitogen-activated protein kinase (MAPK) signaling pathways and molecular docking in vitro. The impact of punicalin on breast cancer-induced osteoclastogenesis, breast cancer cell proliferation, and apoptosis were examined. Transwell assays were also performed. Moreover, we evaluated in vivo effects of punicalin in postmenopausal osteoporosis models and breast cancer bone metastasis model by micro-CT scanning and histomorphometry. Results: Punicalin inhibited osteoclast formation, F-actin ring formation, bone resorption, as well as osteoclast-related gene expression by suppressing the NF-κB signaling pathway. In vitro, punicalin also suppressed the breast cancer-induced osteoclastogenesis, and proliferation, migration as well as invasion of MDA-MB-231 cells and dose-dependently promoted their apoptosis. In vivo, punicalin significantly suppressed breast cancer-induced osteolysis, breast cancer-associated bone metastasis, and ovariectomized (OVX)-mediated osteoporosis by repressing osteoclast and breast cancer cell. Conclusion: Punicalin is expected to offer a novel treatment for the prevention of osteolysis diseases, including osteoporosis and breast cancer-associated osteolysis.

Relationship between Serum Nutritional Factors and Bone Mineral Density: A Mendelian Randomization Study.

PURPOSE: Multiple risk factors have been implicated in the development of osteoporosis. This study examined potential associations between serum nutritional factors and bone mineral density (BMD). METHODS: Six nutritional factors were selected as exposures. Outcomes included total body BMD (n = 66 945); BMD at the forearm (FA), femoral neck (FN) and lumbar spine (LS) (n = 8143, n = 32 735, and n = 28 498, respectively); estimated heel BMD (HL eBMD) (n = 394 929); and HL eBMD stratified by sex (n = 206 496). A 2-sample Mendelian randomization approach was adopted to estimate the association between serum nutritional factors and BMD. The threshold for adjusted P value was 1.39 × 10-3. RESULTS: Serum calcium levels were inversely associated with LS BMD (effect = -0.55; 95% CI, -0.86 to -0.24; P = 0.001), whereas serum selenium levels were positively correlated with HL eBMD (effect = 0.22; 95% CI, 0.10 to 0.33; P = 1.70 × 10-4). Regarding nominal significance, there was a positive association between serum selenium levels and FA BMD. Nominally significant results were also obtained for serum retinol as well as vitamin E levels and HL eBMD. Moreover, sex-specific effects of serum retinol and vitamin E levels on BMD were observed in men. CONCLUSION: Serum calcium and selenium levels influence BMD at specific skeletal sites. This implies that these nutritional factors play crucial roles in bone metabolism.