Background:Malignant neoplasm of bone and articular cartilage (MNBAC), a major cause of cancer-related mortality, disproportionately impacts children and adolescents. However, comprehensive and future-oriented studies are still lacking. Methods:We systematically analyzed global-to-subnational MNBAC burdens, inequalities, and ideal achievable frontiers among those under 20 years old across 953 locations from 1980 to 2021. An advanced attention-based deep-learning pipeline was created for precise forecasting. Results:From 1990 to 2021, the global prevalence and incidence rate of MNBAC among those aged <20 years increased by 14.7 % and 14.3 %, respectively, leading to 139,154 prevalent cases by 2021. This disproportionately affected males and increased progressively with age, peaking in adolescents aged 15-19 years. Despite a slight global decline in MNBAC mortality, notable increases were observed in low-middle SDI region. 87.3 % of countries and 93.8 % of subnational locations experiencing increased mortality were situated in low to middle SDI regions, exemplified by Tokelau (377.8 %) and Indonesia's West Papua (148.6 %). Concurrently, the global YLD/YLL ratio for those <20 years increased, reflecting the ongoing transition from fatal to non-fatal burdens. This shift mainly impacted socio-economically advantaged settings, as 61 % of the top 100 countries were categorized as high and high-middle SDI. However, substantial gaps remain globally, with at least 94.1 % of countries and 81.4 % of subnational locations failing to meet achievable frontiers by 2021. Forecasts to 2040 anticipate further increases in incidence and stagnation in mortality, alongside widening disparities. Approximately 60.0 % of 672 subnational locations are forecasted to exhibit rising prevalence, with 41.2 % in the UK. By 2040, 30.0 % of the top 100 high-prevalence subnational locations will likely be in Sub-Saharan Africa, including 56 % in the UK. Mortality rates are forecasted to remain highest in low SDI region, especially in Eastern Sub-Saharan Africa, accounting for 47.7 % in Kenya alone. Conclusion:The MNBAC burden remains high, especially among adolescents, with anticipated increases in lower-income areas, necessitating targeted healthcare policies and increased investment. The Translational Potential of this Article:This study highlights the growing global burden of MNBAC and the urgent need for age-specific prevention, early detection, and equitable access to healthcare. Enhancing cancer registries, expanding financial protection, and integrating MNBAC management into national cancer control strategies could help reduce disparities and improve outcomes for affected children and adolescents.

Osteoarthritis (OA) is driven in part by chondrocyte senescence, mitochondrial dysfunction and chronic inflammation, yet disease-modifying therapies that directly target these ageing mechanisms are lacking. Here, we identify the grape-seed-derived polyphenol procyanidin C1 (PCC1) as a senotherapeutic candidate that preserves chondrocyte mitochondrial homoeostasis and attenuates senescence via activation of the Nrf2/HO-1 axis. In tert-butyl hydroperoxide-induced senescent chondrocytes, PCC1 reduced senescence-associated β-galactosidase activity, dampened secretion of senescence-associated secretory phenotype factors, restored mitochondrial membrane potential and dynamics, limited extracellular matrix degradation and suppressed NF-κB activation. Network pharmacology and transcriptomic analyses converged on Nrf2 as a potential molecular target of PCC1, which we validated using cellular thermal shift and drug affinity responsive target stability assays. Genetic silencing of Nrf2 abrogated PCC1-mediated protection in vitro, confirming that Nrf2 is required for the anti-senescent and mitochondrial effects of PCC1. In a surgically induced anterior cruciate ligament transection model of OA, PCC1 administration reduced cartilage erosion, preserved matrix organisation and subchondral bone structure, and mitigated synovial inflammation in Nrf2-sufficient mice, whereas Nrf2 deficiency abolished these benefits. Together, these findings establish a mechanistic link between PCC1, Nrf2/HO-1 activation and chondrocyte mitochondrial homoeostasis in osteoarthritis, and support Nrf2-directed senotherapies as a regenerative strategy to slow OA progression.

Background: Glucocorticoids (GCs) are a key pathogenic factor in steroid-induced avascular necrosis of the femoral head (SANFH). GCs can directly damage bone microvascular endothelial cells (BMECs), leading to impaired intraosseous blood supply. Recent studies suggest the Hippo signaling pathway may be involved in the pathogenesis of SANFH; however, its role in vascular endothelial repair and angiogenesis remains unclear. This study aims to investigate the therapeutic effects of human umbilical cord mesenchymal stem cells (hUC-MSCs) on SANFH, with a particular focus on their protective or reparative mechanisms on BMECs. Methods: In vivo, a SANFH mouse model is established and divided into NC, MPS, and hUC-MSCs groups, followed by Micro-CT imagin, hematoxylin and eosin (HE) staining and immunohistochemistry (IHC) (n = 8 per group). In vitro, BMECs are divided into NC, dexamethasone (Dex), hUC-MSCs, and Fer-1 groups to analyze cellular biological behaviors. Target protein expression is assessed using Western blotting and immunofluorescence microscopy. Ferroptosis-related markers are detected via biochemical assays. Mitochondrial ultrastructural changes are observed using transmission electron microscopy. Results: In vivo, the MPS group exhibited significant bone cavitation, sparse trabeculae, and disrupted trabecular architecture in the femoral head. The hUC-MSCs group showed marked improvement in bone microstructure, HE staining showed a significant decrease in the empty lacunae rate in the femoral head, and IHC results revealed markedly increased expression of cluster of differentiation 31 (CD31) and vascular endothelial growth factor (VEGF). In vitro, Dex stimulation suppressed BMECs proliferation. In Dex-treated cells, levels of intracellular reactive oxygen species (ROS), lipid peroxides, ferrous ion (Fe2+), malondialdehyde (MDA), acyl-CoA synthetase long chain family member 4 (ACSL4) and nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) were all increased, while expression of glutathione (GSH) and glutathione Peroxidase 4 (GPX4) was reduced. Transmission electron microscopy revealed plasma membrane rupture and reduction or loss of mitochondrial cristae. Furthermore, Dex promoted Hippo-mediated phosphorylation of Yes-associated protein (YAP)/Transcriptional coactivator with PDZ-binding motif (TAZ), upregulated NOX4 expression, and suppressed CD31 and VEGF expression. Following hUC-MSCs treatment, BMECs demonstrated enhanced proliferation, migration, and tube-forming capacity. Cellular GSH and GPX4 levels increased, antioxidant capacity was restored, peroxide accumulation decreased, and cells were protected from ferroptosis-effects comparable to those in the Fer-1 group. Additionally, hUC-MSCs inhibited YAP/TAZ phosphorylation and promoted elevated expression of CD31 and VEGF. Conclusions: These findings suggest that hUC-MSCs may attenuate Dex-induced ferroptosis in BMECs, enhance BMEC migration and angiogenesis, and improve femoral head microstructure in SANFH through modulation of the Hippo-YAP/TAZ signaling pathway. This study provides novel insights into the therapeutic potential of hUC-MSCs for SANFH.

ABSTRACT Background Charcot Arthropathy (CA) is a destructive joint condition tied to neurotrophic and neuropathic processes. The clinical course is often complicated—high amputation rates and a generally poor prognosis have long made management difficult. Decades of research have brought progress in basic science and clinical care, yet a clear, data‐driven picture of the global research landscape and how it has shifted over time remains, in many ways, incomplete. Objective This study set out to map the core components, current hotspots, and emerging frontiers in the CA literature. Methods We focused on English‐language publications in the Web of Science (WoS) database from 1995 to 2025. Using tools such as CiteSpace, the R package bibliometrix, and GraphPad, we conducted a quantitative analysis of the countries or regions, institutions, authors, collaboration patterns, journals, cited references, and keywords associated with CA‐related publications. Results We screened 349 papers. Annual output has generally trended upward—perhaps a sign of growing interest in the field. The United States ranked first in both total publications (n = 180) and citations (n = 3949), and sat at the center of international collaboration networks. Key authors (e.g., Dane K. Wukich) and institutions (e.g., the University of Texas System) emerged as major contributors; their dense collaborations appear to drive much of the field's progress. The Journal of Foot and Ankle Surgery published the most CA‐related papers (n = 47). Current research hotspots appear to center on the foot and ankle, pathogenesis, and surgical treatment. Looking at keyword trends, the field seems to be moving toward biomechanics, advanced reconstruction, and three‐dimensional imaging. Conclusion This study is the first comprehensive mapping of CA literature over three decades. It highlights the United States' leading role and a shift toward technology in diagnosis and surgery. These findings may guide future research, collaboration, and clinical practice.

Brassinosteroids (BRs) are a class of steroid phytohormones that promote plant growth and tolerance to both biotic and abiotic stress. BAS1/CYP734A1, SOB7/CYP72C1, and BEN1 are three BR-inactivating enzymes characterized in Arabidopsis thaliana. The triple-null mutant bas1-2 sob7-1 ben1-3 exhibits strong BR-overproducing phenotypes. The CYP734A cytochrome P450 protein family is highly conserved across plant species. Ectopic overexpression of grapevine CYP734A15 in Arabidopsis causes severe BR-deficient phenotypes. BRs differentially modulate hypocotyl growth in photomorphogenic and skotomorphogenic seedlings. However, little is known about the potential involvement of light in BR-regulated seedling root growth. In this research, we grew Arabidopsis seedlings of the wild-type (WT) Col-0, the BR-overproducing mutant bas1-2 sob7-1 ben1-3, and two BR-deficient CYP734A15 overexpression mutants CYP734A15ox-3 and CYP734A15ox-4 in either continuous white light or constant darkness, with treatments of either brassinolide (BL, the most bioactive, naturally occurring BR) or the BR biosynthesis inhibitor brassinazole (BRZ) at a wide range of concentrations. Primary root length measurement results showed that light promoted seedling root growth regardless of endogenous BR levels. Both endogenous and exogenous BRs suppressed seedling root growth independently of light. BRZ treatments also suppressed root elongation in light-grown seedlings regardless of endogenous BR levels, probably due to its toxic effects. In the dark, BRZ still slightly suppressed root elongation in CYP734A15ox-3/4 seedlings but the effect switched to moderate promotion for roots growth in Col-0 and bas1-2 sob7-1 ben1-3. Collectively, our work suggests that light and BRs differentially modulate Arabidopsis seedling root growth in a largely independent manner.

Protein homeostasis is vital for organisms and requires chaperones like the conserved Bcl-2-associated athanogene (BAG) co-chaperones that bind to the heat shock protein 70 (HSP70) through their C-terminal BAG domain (BD). Here, we show an unconventional BAG subfamily exclusively found in oomycetes. Oomycete BAGs feature an atypical N-terminal BD with a short and oomycete-specific α1 helix (α1'), plus a C-terminal small heat shock protein (sHSP) domain. In oomycete pathogen Phytophthora sojae, both BD-α1' and sHSP domains are required for P. sojae BAG (PsBAG) function in cyst germination, pathogenicity, and unfolded protein response assisting in 26S proteasome-mediated degradation of misfolded proteins. PsBAGs form homo- and heterodimers through their unique BD-α1' to function properly, with no recruitment of HSP70s to form the common BAG-HSP70 complex found in other eukaryotes. Our study highlights an oomycete-exclusive protein homeostasis mechanism mediated by atypical BAGs, which provides a potential target for oomycete disease control.

Croton yellow vein mosaic virus (CYVMV) is a Begomovirus infecting a wide range of vegetables, ornamentals, and weeds. The monopartite CYVMV genome comprises a single-stranded circular DNA (DNA-A). It is also associated with a DNA-betasatellite (DNA-β) called croton yellow vein mosaic betasatellite (CroYVMB). While DNA-A encodes three RNA silencing suppressors viz. V2/C2/C4, DNA-β encodes βC1, which also acts as silencing suppressor. The V2 protein physically interacts with both itself and V1, which is critical for cell-to-cell movement of CYVMV. However, little is known about the molecular mechanism of how V2 suppresses plant RNA silencing machinery and the defense system. Here, we identified twenty-three putative V2-interacting proteins in Nicotiana benthamiana via affinity purification-mass spectrometry (AP-MS) and performed gene ontology (GO) analysis on these V2-interacting candidates. Particularly, two N. benthamiana (Nb) proteins, Ankyrin repeat domain containing protein (NbANK) and Receptor for Activated C Kinase 1 (NbRACK1), were verified to physically interact with V2 in both yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC). Compared to NbRACK1, NbANK exhibited much stronger binding capacity with V2 in Y2H assays, which was consistent with structural predictions of V2-NbANK and V2-NbRACK1 complexes using AlphaFold 3. Virus-induced gene silencing (VIGS) assays using the pTRV vectors demonstrated that the silencing of NbANK significantly increased CYVMV abundance in N. benthamiana, but did not lead to enhanced pathogenicity. In conclusion, our proteomic analysis identifies specific CYVMV V2 interactors in plants, and NbANK is used as an example to show their critical roles in CYVMV propagation.

Background/Objectives: Glucocorticoid-induced osteonecrosis of the femoral head (GIOFH) is a debilitating condition resulting from impaired bone metabolism and vascular disruption due to prolonged glucocorticoid use. This study aimed to explore the therapeutic potential of salvigenin, a flavonoid with antioxidative and estrogen-like properties, in alleviating GIOFH by modulating estrogen receptor alpha (ESR1) pathways. Methods: A network pharmacology approach was utilized to identify salvigenin’s potential targets and their association with GIOFH. Protein–protein interaction networks, along with Gene Ontology and KEGG pathway analyses, were conducted to clarify salvigenin’s multi-target mechanisms. Molecular docking and dynamics simulations assessed the interaction between salvigenin and ESR1. Experimental validation included in vitro assays on MG63 cells treated with dexamethasone (Dex) to mimic GIOFH, evaluating oxidative stress, apoptosis, osteogenic differentiation, and ESR1 expression. Results: Network analysis identified ESR1, NOS3, and MMP9 as key hub targets of salvigenin. Molecular docking and dynamics simulations confirmed stable binding of salvigenin to ESR1. Salvigenin significantly reduced Dex-induced oxidative stress and apoptosis in osteoblasts while restoring osteogenic differentiation and ESR1 expression. Functional assays showed improved mineralized nodule formation, ALP activity, and mitochondrial integrity in salvigenin-treated cells. Conclusions: Salvigenin exhibits significant therapeutic potential in addressing GIOFH through ESR1-mediated pathways. These results offer a strong foundation for future translational studies and the development of salvigenin-based therapies for glucocorticoid-induced bone disorders.

[This retracts the article DOI: 10.3892/etm.2017.4100.].

Plants produce a group of steroid hormones named brassinosteroids (BRs), with brassinolide (BL) and castasterone (CS) exhibiting highest biological activity. The maintenance of appropriate BR homeostasis is crucial for plant growth and adaptation to environmental conditions. BRs negatively regulate Arabidopsis thaliana seedling photomorphogenesis by promoting hypocotyl elongation in the light. However, both BL and the BR biosynthesis inhibitor brassinazole (BRZ) suppress Arabidopsis hypocotyl growth in the dark, indicating a seemingly contradictory role of BRs in seedling skotomorphogenesis. Using wild-type Col-0 and two independent BR-deficient mutants previously generated by ectopically overexpressing the grapevine BR-inactivating enzyme CYP734A15 in Arabidopsis, we quantified dark-grown hypocotyl length changes in response to BL or BRZ treatments at a wide range of concentrations. The results revealed that BR homeostasis in wild-type Arabidopsis seedlings is nearly optimal yet slightly excessive for achieving maximal hypocotyl growth in the dark. Gentle BRZ treatments slightly reduce seedling BR levels to maximize hypocotyl growth. Treatments with BL and higher concentrations of BRZ suppress hypocotyl growth via distinct mechanisms of overdosing BRs to toxic levels and further reducing BRs to insufficient levels, respectively. For dark-grown BR-deficient mutants, mild BL treatments boosted their BR levels to promote hypocotyl growth, whereas further increases of BL supply were overdosed for hypocotyl growth. BRZ treatments on BR-deficient mutants further reduced the already insufficient BR levels, making their hypocotyls even shorter. In conclusion, optimal BR homeostasis is required to maximize Arabidopsis hypocotyl growth in the dark.

The Arabidopsis thaliana NAC-family transcription factor ATAF2 plays extensive regulatory roles in plant disease resistance, abiotic stress tolerance, leaf senescence, hormone metabolism, and seedling photomorphogenesis. Using Arabidopsis seedlings as the investigation platform, we previously demonstrated that ATAF2 overexpression can increase the endogenous levels of the growth-promoting hormone brassinosteroids (BRs) and suppress the expression of the chlorophyll b (Chl-b) reductase NYC1, which catalyzes the initial step of the degradation of light-harvesting chlorophyll a/b-protein complex of photosystem II (LHCII). ATAF2 also promotes the expression of NIT2, which is involved in the biosynthesis of the auxin indole-3-acetic acid (IAA). Here, we further examined the effects of elevated BR/IAA levels and reduced NYC1 expression on biomass and Chl-a/b accumulations, respectively. Twelve-day-old plants were harvested for biomass and Chl-a/b measurements. While no significant difference of biomass or Chl-a/b accumulations was observed between the wild-type Col-0 and the loss-of-function ataf2-1/2 plants, all three ATAF2 overexpression lines (ATAF2ox-1/2/3) exhibited much higher biomass and Chl-a accumulations as compared to Col-0 and ataf2-1/2, which can at least be partially interpreted as the consequences of higher endogenous BR/IAA levels and reduced NYC1 expression, respectively. The results demonstrate the positive regulatory role of ATAF2 in biomass and Chl-a accumulations. Notably, ATAF2 overexpression does not increase Arabidopsis biomass accumulation at later growth stages, indicating its functional nature of developmental timing acceleration.

Dysregulated mitophagy is essential for mitochondrial quality control within human cancers. However, identifying hub genes regulating mitophagy and developing mitophagy-based treatments to combat drug resistance remains challenging. Herein, BayeDEM (Bayesian-optimized Deep learning for identifying Essential genes of Mitophagy) was proposed for such a task. After Bayesian optimization, BayeDEM demonstrated its excellent performance in identifying critical genes regulating mitophagy of osteosarcoma (area under curve [AUC] of ROC: 98.96%; AUC of PR curve: 100%). CERS1 was identified as the most essential gene regulating mitophagy (mean (|SHAP value|): 4.14). Inhibition of CERS1 sensitized cisplatin-resistant osteosarcoma cells to cisplatin, restricting their growth, proliferation, invasion, migration and colony formation and inducing apoptosis. Mechanistically, inhibition of CERS1 restricted mitophagy to destroy the mitochondrial quality control in cisplatin-resistant osteosarcoma cells, including mitochondrial membrane potential loss and unfavourable mitochondrial dynamics, rendering them susceptible to cisplatin-induced apoptosis. More importantly, mitophagy facilitated the immunosuppressive microenvironment formation by significantly modulating T-cell differentiation, adhesion and antigen presentation, and mitophagy mainly affects malignant osteoblasts in the early-mid developmental stage. Immunologically, mitophagy potentially modulated the MIF signalling transmission between malignant osteoblasts and B cells, DCs, CD8+ T cells, NK cells and monocytes through the MIF-(CD74 + CXCR4) receptor-ligand interaction, thereby modulating the biological functions of these immune cells. Collectively, BayeDEM emerged as a promising tool for oncologists to identify pivotal genes governing mitophagy, thereby enabling mitophagy-centric therapeutic strategies to counteract drug resistance.

Grapevines (Vitis vinifera) are cultivated worldwide with fruits used for fresh consumption, wine brewing, juice, or raisin production. As a group of plant growth-promoting hormones, brassinosteroids (BRs) play extensive roles in multiple aspects of grapevine-environment interactions. BRs can enhance plant biomass accumulation, disease resistance, and tolerance to abiotic stress. Plant BR homeostasis can be modulated by a conserved cytochrome P450 family CYP734A that specifically inactivate BRs. However, grapevine CYP734As haven't been functionally characterized to date. Here, we cloned CYP734A15 from the popular table/raisin grape cultivar Thompson Seedless and demonstrated its BR-inactivating activity via ectopic expression in Arabidopsis thaliana. CYP734A15 overexpression causes BR-deficient dwarfism in Arabidopsis, which can be rescued by exogenous application of brassinolide (BL), the most biologically active BR found in plants. The BR biosynthetic inhibitor brassinazole (BRZ) can abolish Arabidopsis seedling hypocotyl growth difference between CYP734A15 overexpression lines and mock plants harboring the empty vector. CYP734A15 overexpression also abolishes Arabidopsis seedling photomorphogenic phenotypes in high-fluence-rate white light conditions. Our findings collectively indicate that CYP734A15 is a valid brassinosteroid-inactivating P450 enzyme, which can be a potential genome editing target for elevating endogenous BR levels in grapevine.

Brassinosteroids (BRs) are essential plant growth-promoting hormones involved in many processes throughout plant development, from seed germination to flowering time. Since BRs do not undergo long-distance transport, cell- and tissue-specific regulation of hormone levels involves both biosynthesis and inactivation. To date, ten BR-inactivating enzymes, with at least five distinct biochemical activities, have been experimentally identified in the model plant Arabidopsis thaliana. Epigenetic interactions between T-DNA insertion alleles and genetic linkage have hindered analysis of higher-order null mutants in these genes. A previous study demonstrated that the bas1-2 sob7-1 ben1-1 triple-null mutant could not be characterized due to epigenetic interactions between the exonic T-DNA insertions in bas1-2 and sob7-1, causing the intronic T-DNA insertion of ben1-1 to revert to a partial loss-of-function allele. We used CRISPR-Cas9 genome editing to avoid this problem and generated the bas1-2 sob7-1 ben1-3 triple-null mutant. This triple-null mutant resulted in an additive seedling long-hypocotyl phenotype. We also uncovered a role for BEN1-mediated BR-inactivation in seedling cotyledon petiole elongation that was not observed in the single ben1-2 null mutant but only in the absence of both BAS1 and SOB7. In addition, genetic analysis demonstrated that BEN1 does not contribute to the early-flowering phenotype, which BAS1 and SOB7 redundantly regulate. Our results show that BAS1, BEN1, and SOB7 have overlapping and independent roles based on their differential spatiotemporal tissue expression patterns

Steroid (glucocorticoid)-induced necrosis of the femoral head (SONFH) represents a prevalent, progressive, and challenging bone and joint disease characterized by diminished osteogenesis and angiogenesis. Omaveloxolone (OMA), a semi-synthetic oleanocarpane triterpenoid with antioxidant, anti-inflammatory, and osteogenic properties, emerges as a potential therapeutic agent for SONFH. This study investigates the therapeutic impact of OMA on SONFH and elucidates its underlying mechanism. The in vitro environment of SONFH cells was simulated by inducing human bone marrow mesenchymal stem cells (hBMSCs) and human umbilical vein endothelial cells (HUVECs) using dexamethasone (DEX).Various assays, including CCK-8, alizarin red staining, Western blot, qPCR, immunofluorescence, flow cytometry, and TUNNEL, were employed to assess cell viability, STING/NF-κB signaling pathway-related proteins, hBMSCs osteogenesis, HUVECs migration, angiogenesis, and apoptosis. The results demonstrate that OMA promotes DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs by inhibiting the STING/NF-κB signaling pathway. This experimental evidence underscores the potential of OMA in regulating DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs through the STING/NF-κB pathway, thereby offering a promising avenue for improving the progression of SONFH.

IntroductionMetformin (MET), derived from Galega officinalis, stands as the primary first-line medication for the treatment of type 2 diabetes (T2D). Despite its well-documented benefits in mammalian cellular processes, its functions and underlying mechanisms in plants remain unclear.ObjectivesThis study aimed to elucidate MET’s role in inducing plant immunity and investigate the associated mechanisms.MethodsTo investigate the impact of MET on enhancing plant immune responses, we conducted assays measuring defense gene expression, reactive oxygen species (ROS) accumulation, mitogen-activated protein kinase (MAPK) phosphorylation, and pathogen infection. Additionally, surface plasmon resonance (SPR) and microscale thermophoresis (MST) techniques were employed to identify MET targets. Protein-protein interactions were analyzed using a luciferase complementation assay and a co-immunoprecipitation assay.ResultsOur findings revealed that MET boosts plant disease resistance by activating MAPKs, upregulating the expression of downstream defense genes, and fortifying the ROS burst. CALCIUM-DEPENDENT PROTEIN KINASE 28 (CPK28) was identified as a target of MET. It inhibited the interaction between BOTRYTIS-INDUCED KINASE 1 (BIK1) and CPK28, blocking CPK28 threonine 76 (T76) transphosphorylation by BIK1, and alleviating the negative regulation of immune responses by CPK28. Moreover, MET enhanced disease resistance in tomato, pepper, and soybean plants.ConclusionCollectively, our data suggest that MET enhances plant immunity by blocking BIK1-mediated CPK28 phosphorylation.

Background: Glucocorticoids (GCs) are critical regulatory molecules in the body, commonly utilized in clinical practice for their potent anti-inflammatory and immunosuppressive properties. However, prolonged, high-dose GC therapy is frequently associated with femoral head necrosis, a condition known as glucocorticoid-induced osteonecrosis of the femoral head (GC-ONFH). Emerging evidence suggests that enhanced autophagy may mitigate apoptosis, thereby protecting osteoblasts from GC-induced damage and delaying the progression of ONFH. This study aims to evaluate whether human umbilical cord mesenchymal stem cells (hUCMSCs) can alleviate GC-induced osteoblast injury through autophagy modulation. Methods: In vitro, osteoblasts were exposed to GCs for 48 h, followed by co-culture with hUCMSCs for an additional 12 h before further analysis. The osteoblasts were categorized into four experimental groups: (A) control group, (B) Dex group, (C) Dex + hUCMSC group, and (D) Dex + hUCMSC + 3-MA group. In vivo, rabbits were assigned to one of four groups: Con, MPS, core decompression (CD), and CD + hUCMSC (n = 12 per group), and subsequently subjected to CT imaging and HE staining. Results: In vitro results demonstrate that hUCMSC treatment mitigated GC-induced osteoblast apoptosis and preserved osteogenic activity through autophagy modulation. In vivo, infusion of hUCMSCs enhanced trabecular thickness in the femoral head and improved the femoral head microenvironment. Conclusions: These findings suggest that hUCMSCs protect osteoblasts from GC-induced damage by regulating autophagy, offering new insights into the potential therapeutic use of hUCMSCs for treating ONFH via autophagy enhancement.

Recently, there has been growing interest in using cell therapy through core decompression (CD) to treat osteonecrosis of the femoral head (ONFH). Our study aimed to investigate the effectiveness and mechanism of human umbilical cord mesenchymal stem cells (hUCMSCs) in treating steroid-induced ONFH. We constructed a steroid-induced ONFH rabbit model as well as dexamethasone (Dex)-treated bone microvascular endothelial cells (BMECs) model of human femoral head. We injected hUCMSCs into the rabbit femoral head via CD. The effects of hUCMSCs on steroid-induced ONFH rabbit model and Dex-treated BMECs were evaluated via micro-CT, microangiography, histology, immunohistochemistry, wound healing, tube formation, and western blotting assay. Furthermore, we conducted single-cell RNA sequencing (scRNA-seq) to examine the characteristics of endothelial cells, the activation of signaling pathways, and inter-cellular communication in ONFH. Our data reveal that hUCMSCs improved the femoral head microstructure and bone repair and promoted angiogenesis in the steroid-induced ONFH rabbit model. Importantly, hUCMSCs improved the migration ability and angioplasty of Dex-treated BMECs by secreting COL6A2 to activate FAK/PI3K/AKT signaling pathway via integrin α1β1.

Steroid-induced osteonecrosis of the femoral head (SONFH), caused by glucocorticoid (GC) administration, is known to exhibit a high incidence worldwide. Although osteoblast apoptosis has been reported as an important cytological basis of SONFH, the precise mechanism remains elusive. Echinacoside (Ech), a natural phenylethanoid glycoside, exerts multiple beneficial effects, such as facilitation of cell proliferation and anti-inflammatory and anticancer activities. Herein, we aimed to explore the regulatory mechanism underlying glucocorticoid-induced osteoblast apoptosis and determine the protective efficacy of Ech against SONFH. We comprehensively surveyed multiple public databases to identify SONFH-related genes. Using bioinformatics analysis, we identified that the PI3K/AKT/FOXO1 signaling pathway was most strongly associated with SONFH. We examined the protective effect of Ech against SONFH using in vivo and in vitro experiments. Specifically, dexamethasone (Dex) decreased p-PI3K and p-AKT levels, which were reversed following Ech addition. Validation of the PI3K inhibitor (LY294002) and molecular docking of Ech and PI3K/AKT further indicated that Ech could directly enhance PI3K/AKT activity to alleviate Dex-induced inhibition. Interestingly, Dex upregulated the expression of FOXO1, Bax, cleaved-caspase-9, and cleaved-caspase-3 and enhanced MC3T3-E1 apoptosis; application of Ech and siRNA-FOXO1 reversed these effects. In vitro, Ech decreased the number of empty osteocytic lacunae, reduced TUNEL and FOXO1 positive cells, and improved bone microarchitecture. Our results provide robust evidence that PI3K/AKT/FOXO1 plays a crucial role in the development of SONFH. Moreover, Ech may be a promising candidate drug for the treatment of SONFH.

IntroductionBone marrow mesenchymal stem cells (BMSCs) are widely used in tissue engineering and regenerative medicine as seed cells. Due to low amount in bone marrow, BMSCs must be expanded and cultured in vitro before application. However, the senescence of stem cell caused by long-term in vitro culture greatly limits its efficacy of transplantation.MethodsIn this study, we propose an approach based on electromagnetic fields (EMF) treatment to rejuvenate aged BMSCs due to long-term in vitro culture. Aged BMSCs were treated with sinusoidal EMF (50 Hz, 0.4 mT), and stem cell senescence, cell proliferation, cell differentiation, cell stemness and autophagy level were detected. Additionally, aged BMSCs-laden hydrogels were transplanted into the rat critical-sized calvarial defect with or without EMF treatment. The bone formation was evaluated 8 weeks after surgery.ResultsOur results indicated that the BMSCs age significantly after long-term in vitro passaging. The self-renew, multiple differentiation capacity, senescence phenotypes and stemness of aged BMSCs are partly reversed by EMF treatment with a frequency of 50 Hz and strength of 0.4 mT. Moreover, declined autophagy level is observed in BMSCs during long-term in vitro passaging and BMSCs senescence is closely associated with autophagy regulation. Additionally, the mechanistic investigation reveals that EMF treatment rejuvenate senescent BMSCs by enhancing autophagy. Furthermore, EMF treatment significantly promote the therapeutic effect of long-term passaged BMSCs on bone formation in vivo.ConclusionOverall, our study identifies a practical approach for the rejuvenation of old BMSCs and may provide a promising candidate in tissue engineering and stem cell therapy.