BackgroundBitong Mixture (BM) has shown efficacy in alleviating pain in knee osteoarthritis (OA) in clinical practice; however, the molecular mechanisms underlying its therapeutic effects remain to be fully elucidated. This study aimed to identified BM-related OA biomarkers and explore their functional implications.MethodsAn integrative strategy combining bioinformatics prediction and experimental validation was used. Biomarkers were screened from public OA transcriptomic data using differential expression analysis, network pharmacology, and machine learning. Their functions were explored via enrichment and immune infiltration analyses. Molecular docking predicted interactions between herbal compounds and targets. Single-cell analysis characterized biomarker expression in chondrocyte subsets. A rat OA model and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were employed for in vivo validation.ResultsBioinformatic prediction identified three potential biomarkers: MMP9, MMP2, and SPP1. They demonstrated certain diagnostic performance for OA and were implicated in pathways related to extracellular matrix organization and immune regulation. Immune analysis revealed significant correlations, notably between MMP2 and activated dendritic cells (cor = 0.66) and between SPP1 and CD4+ central memory T cells (cor = -0.75). Molecular docking suggested strong binding affinity between luteolin (a BM component) and MMP9. Single-cell analysis indicated high expression of these potential biomarkers in hypertrophic chondrocytes, inflammatory chondrocytes, and fibrochondrocytes. In vivo validation confirmed that BM alleviated OA symptoms and histopathological damage in rats. RT-qPCR results showed that BM treatment alleviated the OA-induced upregulation of MMP9, MMP2, and SPP1 expression.ConclusionMMP9, MMP2, and SPP1 are potential therapeutic biomarkers for BM in OA. The efficacy of BM may be attributed to its regulation of extracellular matrix remodeling and immune responses, which provides a possible mechanistic explanation for its clinical use.

BACKGROUND Stem cell-derived exosomes represent a promising cell-free strategy for bone regeneration, yet the mechanisms underlying their osteogenic effects remain incompletely defined. Hypoxic preconditioning has been reported to enhance exosome bioactivity, but its potential interaction with mechanosensitive signaling pathways during osteogenesis is poorly understood. AIM To evaluate the osteogenic effects of hypoxia-preconditioned adipose-derived stem cell exosomes (HY-Exos) and to examine the possible involvement of Piezo1-dependent calcium signaling. METHODS Bone marrow mesenchymal stem cells were treated in vitro with exosomes derived from adipose-derived stem cells cultured under normoxic or hypoxic conditions. Osteogenic differentiation was assessed by alkaline phosphatase and alizarin red S staining and quantitative polymerase chain reaction. Piezo1 expression and intracellular calcium dynamics were analyzed by western blotting and Fluo-4 AM imaging, with GsMTx4 used for functional inhibition. In vivo , HY-Exos were systemically administered to ovariectomized rats, and bone microarchitecture was evaluated by micro-computed tomography. Statistical analyses were performed using Student’s t -test or one-way ANOVA. RESULTS HY-Exos showed higher cellular uptake and more strongly promoted osteogenic differentiation than normoxic exosomes, as evidenced by increased alkaline phosphatase activity (P < 0.01), mineralized nodule formation (P < 0.001), and upregulated expression of runt-related transcription factor 2 and osterix. HY-Exos were associated with elevated Piezo1 protein expression (P < 0.01) and sustained calcium oscillations, which were suppressed by GsMTx4 (P < 0.001). In ovariectomized rats, HY-Exos improved bone mineral density (P < 0.01) and bone volume/total volume (P < 0.001). CONCLUSION HY-Exos enhance osteogenic differentiation and bone formation and are associated with changes in Piezo1-related calcium signaling. These findings support the therapeutic potential of hypoxia-conditioned exosomes for osteoporosis while indicating a mechanosensitive signaling pathway that warrants further investigation.

Senile osteoporosis (SOP) is driven largely by bone marrow mesenchymal stem cell (BMSC) senescence and mitochondrial dysfunction. S-glutathionylation is an important redox modification regulating mitochondrial homeostasis, yet its role in skeletal aging remains unclear. The objective of this study is to systematically investigate the role of Grx2 deficiency-mediated CD36 S-glutathionylation in BMSC senescence and SOP development. Grx2, p53, and p21 expression in human and mouse BMSCs were analyzed by immunohistochemistry (IHC), western blotting (WB), and polymerase chain reaction (PCR). Aging-related and ovariectomy-induced osteoporosis models were established in Grx2−/− mice for bone metabolism and senescence assessments. BMSC senescence, osteogenesis, and adipogenesis were evaluated by SA-β-Gal and WB, ALP/ARS staining, and ORO staining. Transcriptomic and S-glutathionylated proteomic analyses were performed to identify underlying mechanisms. Fatty acid uptake was quantified using two-color flow cytometry. DAG and MDA levels were measured to assess lipid overload and oxidative injury. Mitochondrial structure and function were evaluated by TEM, Mitotracker, qPCR, NAD+/NADH, ATP, ROS, JC-1, and Seahorse assays. The PI3K/AKT pathway was assessed by WB. Co-IP confirmed CD36 S-glutathionylation, and molecular docking predicted C272 as the key modification site. CD36-C272S mutation and Grx2 overexpression were applied to validate functional mechanisms in vitro and in vivo. Grx2 deficiency, in both male and ovariectomized female mice, accelerates bone loss, inhibits osteoblast formation without altering osteoclast function, and exacerbates BMSC senescence. Through integrated transcriptomic and S-glutathionylated proteomic analysis, we identified the fatty acid transporter CD36 as a critical downstream target of Grx2. Notably, Grx2 deficiency markedly increases the S-glutathionylation of CD36, which not only enhances its fatty acid uptake capacity, leading to the accumulation of toxic lipid metabolites and oxidative damage, but also impairs mitochondrial energy metabolism by inhibiting the PI3K/AKT signaling pathway. Overexpression of Grx2 or the C272S mutation in CD36, which disrupts its S-glutathionylation, can break this harmful cycle and inhibit BMSC senescence. Grx2 deficiency-mediated CD36 S-glutathionylation drives BMSC senescence and SOP, providing new insight into the redox regulatory mechanisms underlying skeletal aging.

ObjectiveThis study aimed to investigate the associations of multi-dimensional lipid metabolism indicators, comprising serum lipid profiles and the degree of fatty infiltration in the musculoskeletal system, with bone mineral density (BMD) and bone turnover markers (BTMs), and to identify independent risk factors for the occurrence and severity of osteoporotic vertebral compression fractures (OVCFs) in postmenopausal women.MethodsThis retrospective study included a total of 133 postmenopausal women from January 2023 to July 2024. Participants were stratified by fracture status and vertebral compression severity. Clinical data, including bone and lipid metabolic indicators and BMD, were retrieved from electronic medical records and MRI reanalysis. Pearson correlation analyzed associations between lipid metabolic indicators and BTMs/BMD. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for OVCFs, with multicollinearity among variables assessed using the variance inflation factor (VIF), and ordinal logistic regression was applied to assess lipid metabolic indicators' impact on vertebral compression severity. Statistical analyses included Student's t-test or Mann-Whitney U test for group comparisons and one-way analysis of variance (ANOVA) for multiple-group comparisons.ResultThis study included 133 participants: 34 controls, 32 with mild, 38 with moderate, and 29 with severe fractures. Age, BMI, BMD, vertebral bone quality (VBQ), the fatty infiltration ratio of the paraspinal muscles (FIR), and lipoprotein(a) [Lp(a)] differed significantly between fracture and control groups (all p < 0.05). VBQ and FIR were negatively correlated with total BMD (r = -0.466, p < 0.05; r = -0.455, p < 0.05) and positively correlated with the ratio of the fractured vertebra compressed sagittal cross-sectional area (RCSA) (r = 0.344, p < 0.05; r = 0.320, p < 0.05) and age (r = 0.615, p < 0.05; r = 0.283, p < 0.05). Univariate and multivariate regression analyses indicated that VBQ (p = 0.043; OR = 4.260, 95% CI: 1.046-17.345), FIR (p = 0.047; OR = 2.372, 95% CI: 1.010-5.572), and Lp(a) (p = 0.048; OR = 1.002, 95% CI: 1.002-1.799) were independently associated with an increased risk of OVCFs. Ordinal logistic regression confirmed VBQ (p = 0.006; OR = 3.168, 95% CI: 1.378-7.282) and FIR (p = 0.034; OR = 1.156, 95% CI: 1.009-1.325) were associated with increased fracture severity.ConclusionVBQ and FIR were independently associated with osteoporotic fractures in postmenopausal women and were further linked to fracture severity, suggesting their potential value in risk stratification and fracture severity assessment. Although Lp(a) showed a statistically significant association with OVCFs, the association was relatively weak, and its clinical significance requires further validation.

CD31hiEMCNhi (type H) vessels orchestrate the bone metabolic microenvironment, yet the epigenetic control of their endothelial identity remains unclear. N6-methyladenosine (m6A), catalyzed by Mettl3, is essential for mRNA fate and emerging as a regulator of skeletal homeostasis. After isolating and validating type H bone microvascular endothelial cells (H-BMECs) from mouse femora, we used lentiviral shRNA and endothelial-specific Cdh5-Cre;Mettl3fl/fl mice to silence Mettl3 in vitro and in vivo. m6A-seq and RNA-seq pinpointed downstream targets; qPCR, Western blot, MeRIP-qPCR, RNA stability, migration, and tube formation assays dissected mechanisms. Local platelet-derived growth factor-BB (PDGF-BB) administration was employed to rescue Mettl3-null phenotypes. Mettl3 expression and global m6A levels were reduced in ovariectomy-induced osteoporosis. Knock-down or genetic deletion of Mettl3 decreased m6A methylation within the 3'UTR of Pdgfrb, accelerated Pdgfrb mRNA decay, blunted PI3K/AKt signaling and impaired H-BMEC proliferation, migration and tube formation. Consequently, type H vessels and trabecular bone mass were markedly diminished. PDGF-BB ligand delivery restored Pdgfrb abundance, reactivated PI3K/AKt, and fully reversed vascular and skeletal defects in Mettl3-null mice. Mettl3-mediated m6A methylation preserves Pdgfrb mRNA stability in bone endothelial cells and is associated with the maintenance of type H vessels, thereby coupling angiogenesis to bone formation. Targeting the Mettl3-m6A-Pdgfrb/PI3K-AKt axis may represent a potential therapeutic strategy for estrogen-deficiency-induced bone loss.

ETHNOPHARMACOLOGICAL RELEVANCE:Wen-Shen-Tong-Luo-Zhi-Tong-Decoction (WSTLZTD) is a traditional Chinese medicine formula, and its effectiveness in the treatment of senile osteoporosis(SOP) has been confirmed by clinical studies. However, the underlying mechanism of WSTLZTD in SOP is unclear. AIM OF THE STUDY:This study aimed to clarify the unique effects of Wen-Shen-Tong-Luo-Zhi-Tong-Decoction(WSTLZTD) on senile osteoporosis(SOP) and its underlying mechanisms. MATERIALS AND METHODS:SAMP6 mice were treated with varying doses of WSTLZTD as the SOP model. Bone loss was evaluated by micro-CT, HE, OCN immunohistochemistry staining, and serum Trap level. Metabolomics studies serum metabolites. ELISA, qPCR, and immunofluorescence were utilized to measure testosterone levels in mouse testis. The effect of testosterone on the mitochondrial energy metabolism of BMSCs was investigated using ROS generation, NAD+/NADH ratio, and WB. Cell senescence was examined by β-galactosidase staining and WB. The effect of TM3 cell conditioned media (CM) on mitochondrial energy metabolism and BMSCs osteogenesis were studied using ALP, ARS, ROS staining, the NAD+/NADH, and WB. RESULTS:WSTLZTD effectively reversed bone loss in SOP model mice, resulting in better bone microstructure, increased BMD, BV/TV, Tb.n, Tb.Th and, and decreased Tb.Sp. WSTLZTD can increase OCN expression and decrease Trap levels. Network pharmacology data suggest that WSTLZTD regulates steroid hormone production, cellular senescence, inflammation. Metabolomic data indicate that WSTLZTD increases testosterone production or metabolism-related metabolites. WSTLZTD enhanced testosterone production and the mRNA expression of genes involved in testosterone synthesis. Testosterone inhibited the decline in osteogenic differentiation and mitochondrial energy metabolism of senescent BMSCs. The decreased testosterone production in senescent TM3 is reversed by WSTLZTD. CM derived from WSTLZTD-treated TM3 cells promoted osteogenic differentiation and mitochondrial energy metabolism of BMSCs. CONCLUSIONS:By increasing testosterone production, WSTLZTD may promote mitochondrial energy metabolism and osteogenic differentiation of senescent BMSCs, thereby exerting its anti-SOP effect.

Spinal cord injury (SCI) arises from traumatic damage to the spinal cord, resulting in varying degrees of sensory, motor, and autonomic dysfunction. Mitochondria, as the primary energy-producing organelles within cells, have garnered increasing attention for their critical role in promoting axonal regeneration following SCI. This review aims to systematically examine the alterations in mitochondrial dynamics post-SCI and to elucidate their influence on axonal regeneration. Furthermore, the review evaluates the current challenges associated with SCI treatment and proposes potential therapeutic strategies for future research. The review comprehensively addresses mitochondrial dynamics, with a focus on key processes such as biogenesis, fusion and fission, mitophagy, trafficking, and anchoring. It delves into the molecular mechanisms by which signaling pathways within neurons and glial cells regulate these mitochondrial processes to facilitate axonal regeneration. Additionally, the review identifies existing challenges in SCI treatment and advocates for targeted interventions in mitochondrial dynamics as a promising therapeutic avenue, offering significant potential for advancing future research and treatment of SCI.

Purpose:Severe residual back pain (RBP) after percutaneous kyphoplasty (PKP) significantly impacts postoperative prognosis and quality of life in patients. The aim of this study was to identify the risk factors for RBP in osteoporotic vertebral compression fracture (OVCF) patients after PKP, to establish a risk prediction model, and to validate its effectiveness. Methods:A case-control study was carried out among OVCF patients, who were assigned to either the training set (these patients were recruited from January 2018 and June 2020) or the validation set (these patients were recruited from July 2020 and December 2020). Risk factors were identified by univariate analysis and multifactor logistic regression analysis. The performance of the prediction model was determined by using the area under the receiver operating characteristic (ROC) curve (AUC) to assess discrimination. A nomogram for risk prediction was constructed, the Hosmer-Lemeshow test and calibration curves were used to assess calibration, and decision curve analysis was used to assess the clinical use of the model. Results:A total of 647 patients were included, 569 cases were used to train the model and 78 cases were used for external validation. Based on the data of model training set, age, bone mineral density, trauma history, posterior fascial edema, platelet distribution width, serum chloride, and middle vertebral height were independent risk factors for RBP after PKP (P ≤ 0.05). The AUC of the risk prediction model constructed thus was 0.788 (95% CI, 0.740-0.836), cut off (0.710, 0.761), with good discrimination. Calibration curves of the model training and validation sets were between the standard curve and the acceptable line, and the Hosmer-Lemeshow test indicated that the model training and validation sets were χ 2 = 6.354 and χ 2 = 7.240, (P = 0.608 and 0.511), respectively, which have good calibration. The decision curve analysis showed that the threshold probability interval of the net benefit value of the model was 6.3%-82.3% for the training set, 8.7%-55.6% and 72.5%-81.3% for the validation set. Conclusion:The constructed model showed good predictive ability in the occurrence of residual back pain after PKP, which can provide a scientific basis and guidance for clinical prevention and treatment.

Background Severe residual back pain (RBP) after percutaneous kyphoplasty (PKP) significantly impacts postoperative prognosis and quality of life in patients. This study aims to identify the risk factors for RBP in patients with osteoporotic vertebral compression fractures (OVCF) following PKP, and to establish and validate a risk prediction model for RBP occurrence after PKP, so as to deepen our understanding of the risk of RBP after PKP, and improve clinical management strategies. Methods 647 patients with OVCF who had PKP surgery from 2018 to 2020 were retrospectively analyzed. 569 cases were used for training the model, and 78 for external validation. The study focused on RBP occurrence after PKP. A nomogram for risk prediction was constructed and the model was tested for accuracy and clinical applicability. Additionally, bootstrap sampling (1000 times) was used for internal validation. Results Based on the model training set, multivariate logistic regression analysis showed that relatively young age, bone mineral density, history of trauma, low back fascia edema, high platelet distribution width value, low serum chlorine value, and no recovery of middle vertebral height were independent risk factors for RBP after PKP (P ≤ 0.05). Calibration curves of the model training and validation sets were between the standard curve and the acceptable line. The Hosmer-Lemeshow goodness-of-fit test indicated that the model training and validation sets were χ2 = 6.354 and χ2 = 7.240, respectively (P = 0.608 and 0.511). The clinical decision-making curve showed that the threshold probability interval of the net benefit value of the model was 6.3–82.3% for the training set, 8.7–55.6%, and 72.5–81.3% for the validation set. Conclusion Each independent risk factor and the combined model had good predictive ability, while the combined model had a more vital predictive ability. The constructed nomogram model for predicting RBP risk showed good diagnostic efficacy, accuracy, and clinical applicability and provided a scientific rationale and guidance for clinical prevention and treatment. Trial registration Clinical trianumber not applicable Study design Retrospective casecontrol study.

BACKGROUND:Postmenopausal osteoporosis (PMOP) is frequently accompanied by depression, and the underlying neuro-skeletal crosstalk remains unclear. Serotonin and sympathetic nervous system (SNS) activity are implicated in both mood and bone regulation. OBJECTIVE:To investigate whether β-sitosterol (βS) alleviates PMOP-associated depression and bone loss through modulation of central 5-hydroxytryptamine (5-HT) synthesis and SNS activity. DESIGN:An integration of in vivo and in vitro studies using mouse models and cellular assays. METHODS:Ovariectomized (OVX) and 5-HT-deficient mice were treated with βS. Behavioral assessments, micro-CT, immunohistochemistry, enzyme-linked immunosorbent assays (ELISA), Western blotting (WB), and molecular docking were employed to evaluate antidepressant effects, bone parameters, and related signaling pathways. In vitro, βS effects on 5-HT production and osteogenesis were assessed in PC12 cells and BMSCs. RESULTS:βS enhanced brain 5-HT synthesis by activating the SIRT1/NRF2/TPH2 pathway and suppressing MAO-A. It alleviated depressive-like behaviors, reduced SNS activity, and prevented bone loss in both OVX and 5-HT-deficient mice. In vitro, βS increased 5-HT secretion in PC12 cells and promoted osteogenic differentiation in BMSCs via conditioned media. CONCLUSION:βS restores neuro-skeletal homeostasis by boosting 5-HT-mediated suppression of SNS activity, thereby improving mood and bone health. These findings identify βS as a promising candidate for treating comorbid PMOP and depression. Our study provides the first evidence linking phytosterol therapy to neuro-skeletal regulation in bone loss.

CONTEXT:Aging leads to senile osteoporosis (SOP), marked by bone loss and increased fracture risk. Macrophages, as active immune cells in bone tissue, play an important role in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) during aging. Wen-Shen-Tong-Luo-Zhi-Tong Decoction (WSTLZTD), a traditional Chinese herbal formula, has been clinically validated for its efficacy in treating SOP. However, the specific mechanisms by which WSTLZTD exerts its anti-SOP effects-particularly through modulating macrophage senescence-remain unclear. OBJECTIVE:The study aims to elucidate the role of WSTLZTD in macrophage senescence and SOP. MATERIALS AND METHODS:Aged mice received low, medium, high-dose WSTLZTD. Bone loss was evaluated via micro-computed tomography, hematoxylin and eosin staining and osteocalcin, tartrate-resistant acid phosphatase marker analysis. Macrophage senescence detection (β-galactosidase staining, p16, p21) and molecular mechanisms by Western blot, immunohistochemistry, immunofluorescence method were investigated. Macrophage-conditioned medium's effects on BMSC osteogenesis and mitochondrial function were assessed through alkaline phosphatase, Alizarin Red S staining, reactive oxygen species and JC-1 mitochondrial membrane potential (ΔΨm) assays. RESULTS:In vivo experiments demonstrated that WSTLZTD effectively ameliorated macrophage senescence and osteoporosis in naturally aged mice. Mechanistically, high-dose WSTLZTD attenuated senescence in bone marrow-derived macrophages by mediating LONP1, concurrently suppressing the cyclic GMP-AMP synthase (cGAS)/STING signaling pathway in BMSCs, thereby enhancing osteogenic differentiation of BMSCs. In vitro studies further confirmed that WSTLZTD-containing serum attenuated the senescent phenotype of macrophages. Notably, the LONP1 inhibitor, LONP1-IN-2, was found to diminish the anti-senescence effects of WSTLZTD on macrophages and BMSC osteogenesis. DISCUSSION AND CONCLUSION:WSTLZTD potentially modulate macrophage senescence via LONP1, which subsequently suppresses the activation of the cGAS/STING pathway in BMSCs, ultimately promoting their osteogenic differentiation and ameliorating osteoporosis.

This study aims to elucidate the role and mechanism of clematichinenoside AR(CAR) in protecting bone marrow mesenchymal stem cells(BMSCs) from hypoxia-induced apoptosis. BMSCs were isolated by the bone fragment method and identified by flow cytometry. Cells were cultured under normal conditions(37℃, 5% CO_2) and hypoxic conditions(37℃, 90% N_2, 5% CO_2) and treated with CAR. The BMSCs were classified into eight groups: control(normal conditions), CAR(normal conditions + CAR), hypoxia 24 h, hypoxia 24 h + CAR, hypoxia 48 h, hypoxia 48 h + CAR, hypoxia 72 h, and hypoxia 72 h + CAR. The cell counting kit-8(CCK-8) assay and terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) were employed to measure cell proliferation and apoptosis, respectively. The number of mitochondria and mitochondrial membrane potential were measured by MitoTracker®Red CM-H2XRo staining and JC-1 staining, respectively. The level of reactive oxygen species(ROS) was measured with the DCFH-DA fluorescence probe. The protein levels of B-cell lymphoma-2 associated X protein(BAX), caspase-3, and optic atrophy 1(OPA1) were determined by Western blot. The results demonstrated that CAR significantly increased cell proliferation. Compared with the control group, the hypoxia groups showed increased apoptosis rates, reduced mitochondria, elevated ROS levels, decreased mitochondrial membrane potential, upregulated expression of BAX and caspase-3, and downregulated expression of OPA1. In comparison to the corresponding hypoxia groups, CAR intervention significantly decreased the apoptosis rate, increased mitochondria, reduced ROS levels, elevated mitochondrial membrane potential, downregulated the expression of BAX and caspase-3, and upregulated the expression of OPA1. Therefore, it can be concluded that CAR may exert an anti-apoptotic effect on BMSCs under hypoxic conditions by regulating OPA1 to maintain mitochondrial homeostasis.

Immune cells play a pivotal role in the complex pathophysiology of ischemic stroke (IS), with their functions dynamically shifting throughout the disease's progression. Throughout the different pathological stages of IS, various immune cells, such as microglia, T cells, neutrophils, NK cells, and mononuclear/macrophages, contribute uniquely to the disease's trajectory. Although thrombolytic therapy remains the standard treatment for IS, its efficacy is limited by a narrow therapeutic window, underscoring the need for alternative or adjunctive therapeutic strategies. Increasingly, the therapeutic potential of Traditional Chinese Medicine (TCM) has gained recognition for its beneficial effects across multiple phases of IS. Notably, TCM interventions have been shown to attenuate early inflammatory responses and neural injury by targeting immune cells, particularly microglia. Furthermore, during the recovery phase, TCM may promote white matter repair and functional recovery through the regulation of neuroimmune interactions. This review offers a comprehensive analysis of the dynamic roles and signaling pathways of immune cells in IS, and further investigates the mechanistic basis of TCM's immunomodulatory effects. While considerable progress has been made, significant challenges remain in fully elucidating the underlying mechanisms of TCM and in optimizing its integration into current IS treatment frameworks.

The "Warburg effect", a hallmark of Osteosarcoma(OS), results in lactate accumulation due to aerobic glycolysis. The role and underlying mechanisms of lactate in OS are not well understood. Herein, the lactate-activated hydroxycarboxylate receptor 1(HCAR1) is found to promote OS progression via inhibiting the transcription of anti-oncogene downstream of STAT1/2. The phosphorylation level of STAT1/2 holds considerable significance for transcriptional activity. In this study, protein phosphatase 2A(PP2A) is identified as the tyrosine phosphatase of STAT1/2. Lactate-activated HCAR1, facilitating PP2A interaction with phosphorylated STAT1/2 via β-Arrestin 2, resulting in STAT1/2 dephosphorylation, a key process linked to the aggressive behavior of OS. Using PP2A inhibitor Endothall can abolish the dephosphorylation effect of HCAR1 on STAT1/2, inhibit cancer cell proliferation, migration, and cell cycle, and promote apoptosis. Moreover, the combination of Endothall and Cisplatin is high synergistic in treating OS. In conclusion, the study elucidates the pro-oncogenic role of lactate-activated HCAR1 in OS.

Objective:This study aimed to construct a nomogram to predict the likelihood of early recurrence in patients with lumbar disc herniation (LDH) following unilateral biportal endoscopic (UBE) surgery. Methods:A retrospective analysis was conducted on LDH patients who underwent UBE surgery in our department between January 1, 2022, and December 31, 2023. The eligible cohort was randomly divided into training and validation sets in a 7:3 ratio. Key predictors for the nomogram were identified through a combination of least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression analysis. The model's performance was assessed using the C-index, the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis. The validation set was used to further evaluate the model's robustness. Results:A total of 289 patients were included in the study, among whom 50 experienced recurrent LDH (rLDH). Five risk factors were identified as significant predictors for rLDH: width of protrusion base (WPB), bone removal range (BRR), Modic changes, type of LDH, and middle vertebral space height (MVH). The C-index values for the training and validation sets were 0.834 and 0.804, respectively. The AUC values were 0.834 (95% CI: 0.750-0.918) in the training set and 0.804 (95% CI: 0.697-0.910) in the validation set. Calibration curves demonstrated excellent concordance between the predicted and observed outcomes. Decision curve analysis indicated that using the nomogram to predict rLDH risk provided a positive net benefit when the threshold probability was between 4% and 63%. Conclusion:This study successfully developed and validated a nomogram to predict early recurrence in LDH patients following UBE surgery. The model provides a valuable tool for clinicians to assess individual rLDH risk, enabling timely interventions to improve postoperative outcomes.

Introduction Postmenopausal osteoporosis (PMOP) stems from estrogen deficiency, which leads to reduced central serotonin (5-HT) levels, induces depressive-like behaviors, enhances sympathetic nervous system (SNS) activity, and disrupts bone homeostasis. However, the underlying mechanisms and potential therapeutic strategies targeting this pathway remain incompletely understood. Objective To test whether phytoestrogens diosgenin (DG) can inhibit bone loss in PMOP by restoring the 5-HT-SNS-bone metabolism circuit. Methods Ovariectomized (OVX) mice and a pharmacological 5-HT-depletion model were used to quantify the DG’s impact on brain 5-HT synthesis, SNS output, and skeletal integrity. PC12 cells were probed to determine whether DG activation of estrogen receptor-alpha (ERα) and its downstream PI3K/AKT/GSK3β cascade regulated the 5-HT synthase tryptophan hydroxylase-2 (TPH2) and the catabolic enzyme monoamine oxidase A (MAOA). Results DG triggers activation of PI3K/AKT/GSK3β via binding to membrane ERα, leading to increased central 5-HT levels, reduced SNS hyperactivity, and preservation of bone mass in OVX mice. In vitro, DG increased neuronal 5-HT supply by upregulating TPH2 and downregulating MAOA, mediated through the ERα-PI3K/AKT/GSK3β pathway. Conclusion DG stabilizes the 5-HT-SNS-bone formation loop by repairing estrogen deficiency-induced 5-HT reduction, thereby preventing bone loss in PMOP. These findings highlight DG as a promising therapeutic candidate for mitigating central 5-HT deficiency and protecting skeletal health in postmenopausal women

Background: Postmenopausal osteoporosis (PMOP) is frequently accompanied by depression, and the underlying neuro-skeletal crosstalk remains unclear. Serotonin and sympathetic nervous system (SNS) activity are implicated in both mood and bone regulation. Objective: To investigate whether (3-sitosterol ((3S) alleviates PMOP-associated depression and bone loss through modulation of central 5-hydroxytryptamine (5-HT) synthesis and SNS activity. Design: An integration of in vivo and in vitro studies using mouse models and cellular assays. Methods: Ovariectomized (OVX) and 5-HT-deficient mice were treated with (3S. Behavioral assessments, micro-CT, immunohistochemistry, enzyme-linked immunosorbent assays (ELISA), Western blotting (WB), and molecular docking were employed to evaluate antidepressant effects, bone parameters, and related signaling pathways. In vitro, (3S effects on 5-HT production and osteogenesis were assessed in PC12 cells and BMSCs. Results: (3S enhanced brain 5-HT synthesis by activating the SIRT1/NRF2/TPH2 pathway and suppressing MAO-A. It alleviated depressive-like behaviors, reduced SNS activity, and prevented bone loss in both OVX and 5-HT-deficient mice. In vitro, (3S increased 5-HT secretion in PC12 cells and promoted osteogenic differentiation in BMSCs via conditioned media. Conclusion: (3S restores neuro-skeletal homeostasis by boosting 5-HT-mediated suppression of SNS activity, thereby improving mood and bone health. These findings identify (3S as a promising candidate for treating co-morbid PMOP and depression. Our study provides the first evidence linking phytosterol therapy to neuro-skeletal regulation in bone loss.

Articular cartilage injury is one of the most common diseases in orthopedic clinics. Following an articular cartilage injury, an inability to resist vascular invasion can result in cartilage calcification by newly formed blood vessels. This process ultimately leads to the loss of joint function, significantly impacting the patient's quality of life. As a result, developing anti-angiogenic methods to repair damaged cartilage has become a popular research topic. Despite this, tissue engineering, as an anti-angiogenic strategy in cartilage injury repair, has not yet been adequately investigated. This exhaustive literature review mainly focused on the process and mechanism of vascular invasion in articular cartilage injury repair and summarized the major regulatory factors and signaling pathways affecting angiogenesis in the process of cartilage injury. We aimed to discuss several potential methods for engineering cartilage repair with anti-angiogenic strategies. Three anti-angiogenic tissue engineering methods were identified, including administering angiogenesis inhibitors, applying scaffolds to manage angiogenesis, and utilizing in vitro bioreactors to enhance the therapeutic properties of cultured chondrocytes. The advantages and disadvantages of each strategy were also analyzed. By exploring these anti-angiogenic tissue engineering methods, we hope to provide guidance for researchers in related fields for future research and development in cartilage repair. We start with the mechanisms of vascular invasion in articular cartilage, focusing on the regulatory factors and signaling pathways that play a role in angiogenesis. We then propose several strategies for repairing articular cartilage damage from a tissue engineering perspective, focusing on anti-angiogenesis, in conjunction with the discussed regulatory factors and signaling pathways.image

BACKGROUND:Narenmandula is a classic ancient remedy in Inner Mongolia, historically used for gastrointestinal diseases. In recent decades, Inner Mongolia Medical University found that it has a significant effect in promoting fracture healing and increasing bone density, and has been used to treat postmenopausal osteoporosis (PMOP), but its mechanism is unclear. OBJECTIVE:Identify the mechanism of action of Narenmandula for PMOP treatment. METHODS:Network pharmacology, molecular docking and ovarian departing rat models were used to verify the relevant mechanism of Narenmandula in the treatment of PMOP. RESULTS:We confirmed that NRMDL prescription can improve OVX-induced bone loss, improve trabecular density, and relieve osteoporosis. Upon screening of network pharmacology, we obtained 238 overlapping genes of Narenmandula and PMOP, and analyzed AKT, IL1B, and IL6 as key genes by network topology. Among the 1143 target genes that interact with PMOP, 107 NRMDL active compounds correspond to 345 target genes and 238 overlapping genes. Network topology analysis showed the top 8 active ingredients, such as quercetin and kaempferol, and the top 20 key genes, such as AKT, IL1B, IL6, INS, JUN, STAT3, TNF, TP53, etc. Enrichment analysis revealed involvement of PI3K-Akt, HIF-1, FoxO, MAPK, and TNF signaling pathways. In addition, we found the most important active compounds bind tightly to core proteins, which were verified by molecular docking analysis. The AKT-related pathway had good binding energy, and the pathway was verified by cell and animal experiments. CONCLUSION:The potential mechanism and efficacy of Narenmandula against PMOP may be related to the PI3K-AKT pathway.

BACKGROUND:Promoting the balance between bone formation and bone resorption is the main therapeutic goal for postmenopausal osteoporosis (PMOP), and bone marrow mesenchymal stem cells (BMSCs) osteogenic differentiation plays an important regulatory role in this process. Recently, several long non-coding RNAs (lncRNAs) have been reported to play an important regulatory role in the occurrence and development of OP and participates in a variety of physiological and pathological processes. However, the role of lncRNA tissue inhibitor of metalloproteinases 3 (lncTIMP3) remains to be investigated.METHODS:The characteristics of BMSCs isolated from the PMOP rat model were verified by flow cytometry assay, alkaline phosphatase (ALP), alizarin red and Oil Red O staining assays. Micro-CT and HE staining assays were performed to examine histological changes of the vertebral trabeculae of the rats. RT-qPCR and western blotting assays were carried out to measure the RNA and protein expression levels. The subcellular location of lncTIMP3 was analyzed by FISH assay. The targeting relationships were verified by luciferase reporter assay and RNA pull-down assay.RESULTS:The trabecular spacing was increased in the PMOP rats, while ALP activity and the expression levels of Runx2, Col1a1 and Ocn were all markedly decreased. Among the RNA sequencing results of the clinical samples, lncTIMP3 was the most downregulated differentially expressed lncRNA, also its level was significantly reduced in the OVX rats. Knockdown of lncTIMP3 inhibited osteogenesis of BMSCs, whereas overexpression of lncTIMP3 exhibited the reverse results. Subsequently, lncTIMP3 was confirmed to be located in the cytoplasm of BMSCs, implying its potential as a competing endogenous RNA for miRNAs. Finally, the negative targeting correlations of miR-214 between lncTIMP3 and Smad4 were elucidated in vitro.CONCLUSION:lncTIMP3 may delay the progress of PMOP by promoting the activity of BMSC, the level of osteogenic differentiation marker gene and the formation of calcium nodules by acting on the miR-214/Smad4 axis. This finding may offer valuable insights into the possible management of PMOP.