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Abstract In this study, a chromosome-level genome of the tropical sea cucumber Stichopus monotuberculatus was generated by a combination of Nanopore long-read, Illumina short-read, and Hi-C sequencing technologies. The final assembly was 810.54 Mb in length, with contig N50 and scaffold N50 values of 10.15 Mb and 35.36 Mb, respectively. This assembly comprised 23 pseudo-chromosomes, covering 99.82% of the genome. Completeness analysis using BUSCO indicated that 97.8% of the metazoan conserved genes were presented in their entirety. A total of 29,596 protein-coding genes were predicted, with functional annotations available for 94.43% of these genes. The high-quality genome assembly produced in this study may provide an essential foundation for future researches on resource conservation and genetic breeding of S. monotuberculatus.

In this study, we present the complete mitochondrial genome of Rhinogobius shennongensis, sequenced using the Illumina HiSeq platform. The result is a circular mitogenome of 16,500 base pairs (bp) with a pronounced A + T nucleotide bias. Phylogenetic analysis was conducted using both Bayesian inference (BI) and maximum-likelihood (ML) methods, utilizing the complete mitochondrial genomes of R. shennongensis and 19 additional Rhinogobius species. The analysis indicated a close mitochondrial relationship between R. maculagenys and R. shennongensis. This research not only enriches genetic resources but also supports phylogenetic studies within the genus Rhinogobius. To further clarify evolutionary dynamics, additional mitochondrial genome sequencing of other Rhinogobius species is essential.

Abstract Background The activation of endoplasmic reticulum (ER) stress is an early pathological hallmark of Alzheimer’s disease (AD) brain, but how ER stress contributes to the onset and development of AD remains poorly characterized. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a non-canonical neurotrophic factor and an ER stress inducible protein. Previous studies reported that MANF is increased in the brains of both pre-symptomatic and symptomatic AD patients, but the consequence of the early rise in MANF protein is unknown. Methods We examined the expression of MANF in the brain of AD mouse models at different pathological stages. Through behavioral, electrophysiological, and neuropathological analyses, we assessed the level of synaptic dysfunctions in the MANF transgenic mouse model which overexpresses MANF in the brain and in wild type (WT) mice with MANF overexpression in the hippocampus. Using proteomic and transcriptomic screening, we identified and validated the molecular mechanism underlying the effects of MANF on synaptic function. Results We found that increased expression of MANF correlates with synapse loss in the hippocampus of AD mice. The ectopic expression of MANF in mice via transgenic or viral approaches causes synapse loss and defects in learning and memory. We also identified that MANF interacts with ELAV like RNA-binding protein 2 (ELAVL2) and affects its binding to RNA transcripts that are involved in synaptic functions. Increasing or decreasing MANF expression in the hippocampus of AD mice exacerbates or ameliorates the behavioral deficits and synaptic pathology, respectively. Conclusions Our study established MANF as a mechanistic link between ER stress and synapse loss in AD and hinted at MANF as a therapeutic target in AD treatment.

Abstract Sea cucumbers are predominant deposit feeders in benthic ecosystems, providing protective benefits to coral reefs by reducing disease prevalence. However, how they receive sufficient nutrition from seabed sediments remains poorly understood. Here, we investigate Holothuria leucospilota, an ecologically significant tropical sea cucumber, to elucidate digestive mechanisms underlying marine deposit-feeding. Genomic analysis reveals intriguing evolutionary adaptation characterized by an expansion of digestive carbohydrase genes and a contraction of digestive protease genes, suggesting specialization in digesting microalgae. Developmentally, two pivotal dietary shifts, namely, from endogenous nutrition to planktonic feeding, and from planktonic feeding to deposit feeding, induce changes in digestive tract enzyme profiles, with adults mainly expressing carbohydrases and lipases. A nuanced symbiotic relationship exists between gut microbiota and the host, namely, specific resident bacteria supply crucial enzymes for food digestion, while other bacteria are digested and provide assimilable nutrients. Our study further identifies Holothuroidea lineage-specific lysozymes that are restrictedly expressed in the intestines to support bacterial digestion. Overall, this work advances our knowledge of the evolutionary innovations in the sea cucumber digestive system which enable them to efficiently utilize nutrients from seabed sediments and promote food recycling within marine ecosystems.

Abstract Here we review scanning tunneling microscopy research on the surface determination for various types of kagome materials, including 11-type (CoSn, FeSn, FeGe), 32-type (Fe3Sn2), 13-type (Mn3Sn), 135-type (AV3Sb5, A = K, Rb, Cs), 166-type (TbMn6Sn6, YMn6Sn6 and ScV6Sn6), and 322-type (Co3Sn2S2 and Ni3In2Se2). We first demonstrate that the measured step height between different surfaces typically deviates from the expected value of ±0.4 ∼0.8Å, which is owing to the tunneling convolution effect with electronic states and becomes a serious issue for Co3Sn2S2 where the expected Sn-S interlayer distance is 0.6Å. Hence, we put forward a general methodology for surface determination as atomic step geometry imaging, which is fundamental but also experimentally challenging to locate the step and to image with atomic precision. We discuss how this method can be used to resolve the surface termination puzzle in Co3Sn2S2. This method provides a natural explanation for the existence of adatoms and vacancies, and beyond using unknown impurity states, we propose and use designer layer-selective substitutional chemical markers to confirm the validity of this method. Finally, we apply this method to determine the surface of a new kagome material Ni3In2Se2, as a cousin of Co3Sn2S2, and we image the underlying kagome geometry on the determined Se surface above the kagome layer, which directly visualizes the p-d hybridization physics. We emphasize that this general method does not rely on theory, but the determined surface identity can provide guidelines for first-principles calculations with adjustable parameters on the surface-dependent local density of states and quasi-particle interference patterns.

Abstract Dictyophora rubrovalvata is a valuable fungus homologous to food and medicine, and its polysaccharide have been gaining increasing attention because of its plentiful activity. However, the structure and activity of its homogeneous polysaccharide have not been studied enough. In this study, two polysaccharides DRP-I and DRP-II were purified from D. rubrovalvata. Their structures were characterized by chemical composition, monosaccharide composition analysis, methylation analysis and nuclear magnetic resonance spectroscopy. The results showed that DRP-I and DRP-II were neutral heteropolysaccharides with molecular weights of 5.79 × 103 and 1.25 × 104 Da, respectively, which were composed of mannose, galactose, glucose, xylose and fucose. The main chains were → 6)-α-D-Galp-(1 → 6)-α-D-Galp-(2,1 → 6)-α-D-Manp-(2,1 → 6)-α-D-Galp-(1, and branch chains were β-D-Xylp-(1 → 3)-α-L-Fucp-(1 → 4)-α-D-Manp-(1 → and α-D-Galp-(1 → 3)-α-D-Galp-(1 → . The in vitro immunoactivity assays on dendritic cells showed that DRP-I and DRP-II could up-regulate the expression of IL-10 and IL-6 and inhibit the expression of TNF-α in a concentration-dependent manner. This research indicated that DRP-I and DRP-II possessed immunoactivity by balancing the excessive inflammation, and molecular weight is an important factor affecting immunoactivity. Graphical Abstract

Abstract The interplay of topology, magnetism, and correlations gives rise to intriguing phases of matter. In this study, through state-of-the-art angle-resolved photoemission spectroscopy, density functional theory, and dynamical mean-field theory calculations, we visualize a fourfold degenerate Dirac nodal line at the boundary of the bulk Brillouin zone in the antiferromagnet YMn2Ge2. We further demonstrate that this gapless, antiferromagnetic Dirac nodal line is enforced by the combination of magnetism, space-time inversion symmetry, and nonsymmorphic lattice symmetry. The corresponding drumhead surface states traverse the whole surface Brillouin zone. YMn2Ge2 thus serves as a platform to exhibit the interplay of multiple degenerate nodal physics and antiferromagnetism. Interestingly, the magnetic nodal line displays a d-orbital dependent renormalization along its trajectory in momentum space, thereby manifesting Hund’s coupling. Our findings offer insights into the effect of electronic correlations on magnetic Dirac nodal lines, leading to an antiferromagnetic Hund nodal line.

Abstract Purpose To evaluate the difference in the diagnostic efficacy of 18F-PSMA-1007 PET/CT and pelvic MRI in primary prostate cancer, as well as the correlation between the two methods and histopathological parameters and serum PSA levels. Methods A total of 41 patients with suspected prostate cancer who underwent 18F-PSMA-1007 PET/CT imaging in our department from 2018 to 2023 were retrospectively collected. All patients underwent 18F-PSMA-1007 PET/CT and MRI scans. The sensitivity, PPV and diagnostic accuracy of MRI and 18F-PSMA-1007 PET/CT in the diagnosis of prostate cancer were calculated after comparing the results of MRI and 18F-PSMA-1007 PET/CT with biopsy. The Spearman test was used to calculate the correlation between 18F-PSMA-1007 PET/CT, MRI parameters, histopathological indicators, and serum PSA levels. Results Compared with histopathological results, the sensitivity, PPV and diagnostic accuracy of 18F-PSMA-1007 PET/CT in the diagnosis of prostate cancer were 95.1%, 100.0% and 95.1%, respectively. The sensitivity, PPV and diagnostic accuracy of MRI in the diagnosis of prostate cancer were 82.9%, 100.0% and 82.9%, respectively. There was a mild to moderately positive correlation between Gleason (Gs) score, Ki-67 index, serum PSA level and 18F-PSMA-1007 PET/CT parameters (p 0.05). Conclusion Compared with MRI, 18F-PSMA-1007 PET/CT has higher sensitivity and diagnostic accuracy in the detection of malignant prostate tumors. In addition, the Ki-67 index and AMACR (P504S) expression were only correlated with 18F-PSMA-1007 PET/CT parameters. Gs score and serum PSA level were correlated with 18F-PSMA-1007 PET/CT and MRI parameters. 18F-PSMA-1007 PET/CT examination can provide certain reference values for the clinical diagnosis, evaluation, and treatment of malignant prostate tumors.

Parkinson's disease (PD) is characterized by age-dependent neurodegeneration and the accumulation of toxic phosphorylated [alpha]-synuclein (pS129-[alpha]-syn). The mechanisms underlying these crucial pathological changes remain unclear. Mutations in parkin RBR E3 ubiquitin protein ligase (PARK2), the gene encoding parkin that is phosphorylated by PTEN-induced putative kinase 1 (PINK1) to participate in mitophagy, cause early onset PD. However, current parkin-KO mouse and pig models do not exhibit neurodegeneration. In the current study, we utilized CRISPR/Cas9 technology to establish parkin-deficient monkey models at different ages. We found that parkin deficiency leads to substantia nigra neurodegeneration in adult monkey brains and that parkin phosphorylation decreases with aging, primarily due to increased insolubility of parkin. Phosphorylated parkin is important for neuroprotection and the reduction of pS129-[alpha]-syn. Consistently, overexpression of WT parkin, but not a mutant form that cannot be phosphorylated by PINK1, reduced the accumulation of pS129-[alpha]-syn. These findings identify parkin phosphorylation as a key factor in PD pathogenesis and suggest it as a promising target for therapeutic interventions., Introduction Parkinson's disease (PD) is a prevalent neurodegenerative disease that affects 1%-2% of individuals over the age of 65 years (1). Although the majority of PD cases are sporadic with [...]

The aim of this study was to explore the impacts of incorporating α-lipoic acid (LA) in a high-fat diet (HFD) on growth, lipid metabolism and mitochondrial function in Lateolabrax maculatus. A normal-fat diet (NFD, 10 % lipid), a high-fat diet (HFD, 16 % lipid) and three LA-added HFD (200, 400, or 600 mg kg−1 LA) were prepared and fed to five group of L. maculatus for 57 days. Supplementation of 400 mg kg−1 LA to the HFD improved growth performance and feed utilization. LA treatment reduced the lipids concentration in serum and liver. Moreover, application of 400 mg kg−1 LA in HFD notably decreased the activity of transaminases in serum. Liver oil red O staining results revealed the larger area of red lipid droplets in HFD group compared to the NFD group. Also, abdominal fat HE staining results showed larger adipocytes in the HFD group. Interestingly, LA application led to a reduction in the area of red lipid droplets and a decrease in the size of adipocytes. Furthermore, LA addition alleviated the HFD-induced oxidative stress as identified by enhanced mitochondrial citrate synthase, isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, and succinate dehydrogenase activities. Meanwhile, LA administration induced the activation of mitochondrial biogenesis, and up-regulated the expression of autophagy-related genes. In conclusion, LA incorporation into HFD for L. maculatus promoted growth performance, enhanced liver mitochondrial function, and mitigated excessive fat accumulation in the liver.

Objectives Peritoneal dialysis (PD) serves as a vital renal replacement therapy for patients with end-stage kidney disease (ESKD). γ-Gamma-glutamyl transferase (γ-GGT) is a recognized predictor of oxidative stress and mortality. This study aimed to assess the prognostic significance of γ-GGT in predicting all-cause and cardiovascular mortality among PD patients.Methods A retrospective study was conducted, enrolling 640 PD patients from a single center. The one-year, three-year, and five-year mortality rates for all causes and cardiovascular causes were evaluated. Kaplan–Meier survival analysis and multivariate Cox regression analysis were performed.Results Within five years of initiating PD, the observed all-cause mortality rates at one, three, and five years were 11.72%, 16.09%, and 23.44%, while cardiovascular mortality rates were 2.97%, 7.34%, and 11.09%, respectively. Lower γ-GGT levels were associated with decreased all-cause mortality during one-, three-, and five-year follow-ups, along with reduced cardiovascular mortality in the first and third years, as indicated by Kaplan–Meier analysis on median γ-GGT groupings. Multivariate Cox regression analysis showed significantly decreased hazard ratios (HRs) for one- to five-year all-cause mortality and cardiovascular mortality in the lower γ-GGT group compared to higher groups. However, when sex differences were eliminated using separate tertile groupings for males and females, only the one- and three-year all-cause mortality rates demonstrated significantly reduced hazard ratios (HRs) in the lower γ-GGT groups.Conclusion This retrospective study suggests that γ-GGT levels have prognostic significance in predicting one- and three-year all-cause mortality among PD patients when accounting for sex differences.

Effective treatment of plant biomass with potentially toxic elements (PTEs) is crucial for phytoremediation. Hydrothermal carbonization (HTC) offers an economical and eco-friendly solution by converting biomass into high-value hydrochar. However, the effects of reaction temperature and medium on the characteristics and metals distribution in hydrochars from PTEs-containing biomass remain unclear. This study explores the effects of different hydrothermal temperature (180–240 °C) and reaction media (H2O, HCl, H2SO4, H3PO4) on the hydrothermal properties of willow biomass containing PTEs, and the distribution and transfer rules of PTEs (Cd and Zn) and the application potential of hydrochar. The results indicated that hydrothermal temperature and acid medium significantly influenced WB conversion, affecting hydrochar properties such as carbonization degree and surface functional groups. Higher hydrothermal temperatures enhanced Cd and Zn fixation in the solid phase, while acid facilitated their migration to the liquid phase. More than 91.08 % of Cd and 88.41 % of Zn in the acid-added system are migrated into the liquid phase at hydrothermal temperature of 180 °C Hydrochar prepared under 180 °C and H3PO4 exhibited excellent adsorption performance for Cd2+ and Cu2+ (2.17 mg/g and 34.38 mg/g, respectively) in aqueous solution. Additionally, hydrochars exhibit high calorific values (20.52–28.01 MJ/kg), suggesting their potential as biofuel. This study provides technical foundation to support the resource processing and safe utilization of forest biomass containing PTEs.

In this study, a comprehensive analysis is presented on the complete mitochondrial genome and phylogenetic relationships of Devario shanensis, an endemic species to the Irrawaddy drainage in southwestern China. The complete mitogenome sequence of D. shanensis was sequenced to be 16,860 bp long and encompassed 13 protein-coding genes, 22 tRNA genes, two rRNA genes and a non-coding control region. The overall AT content (61.1%) was much higher than GC content (38.9%). Phylogenetic analyses employing maximum-likelihood and Bayesian inference methods on the complete mitogenomes, including D. shanensis and 13 other species, unveiled a close genomic relationship between D. shanensis and Devario interruptus. This work will contribute to the genetic resource enrichment and phylogenetic researches on genus Devario.

Highlights Mo–MXene/Mo–metal sulfides with semiconductor junctions and Mott–Schottky junctions are designed. Built-in electric field are constructed in semiconductor–semiconductor–metal heterostructure, enhancing dielectric polarization and impedance matching. Density functional theory calculations and Radar cross-section simulations confirmed the excellent electromagnetic wave absorption ability of heterostructures.

Abstract Huntington’s disease (HD) is a monogenic neurodegenerative disease, caused by the CAG trinucleotide repeat expansion in exon 1 of the Huntingtin (HTT) gene. The HTT gene encodes a large protein known to interact with many proteins. Huntingtin-associated protein 40 (HAP40) is one that shows high binding affinity with HTT and functions to maintain HTT conformation in vitro. However, the potential role of HAP40 in HD pathogenesis remains unknown. In this study, we found that the expression level of HAP40 is in parallel with HTT but inversely correlates with mutant HTT aggregates in mouse brains. Depletion of endogenous HAP40 in the striatum of HD140Q knock-in (KI) mice leads to enhanced mutant HTT aggregation and neuronal loss. Consistently, overexpression of HAP40 in the striatum of HD140Q KI mice reduced mutant HTT aggregation and ameliorated the behavioral deficits. Mechanistically, HAP40 preferentially binds to mutant HTT and promotes Lysine 48-linked ubiquitination of mutant HTT. Our results revealed that HAP40 is an important regulator of HTT protein homeostasis in vivo and hinted at HAP40 as a therapeutic target in HD treatment.

Abstract Although messenger RNA translation is tightly regulated to preserve protein synthesis and cellular homeostasis, chronic exposure to interferon‐γ (IFN‐γ) in several cancers can lead to tryptophan (Trp) shortage via the indoleamine‐2,3‐dioxygenase (IDO)‐ kynurenine pathway and therefore promotes the production of aberrant peptides by ribosomal frameshifting and tryptophan‐to‐phenylalanine (W>F) codon reassignment events (substitutants) specifically at Trp codons. However, the effect of Trp depletion on the generation of aberrant peptides by ribosomal mistranslation in gastric cancer (GC) is still obscure. Here, it is shows that the abundant infiltrating lymphocytes in EBV‐positive GC continuously secreted IFN‐γ, upregulated IDO1 expression, leading to Trp shortage and the induction of W>F substitutants. Intriguingly, the production of W>F substitutants in EBV‐positive GC is linked to antigen presentation and the activation of the mTOR/eIF4E signaling pathway. Inhibiting either the mTOR/eIF4E pathway or EIF4E expression counteracted the production and antigen presentation of W>F substitutants. Thus, the mTOR/eIF4E pathway exposed the vulnerability of gastric cancer by accelerating the production of aberrant peptides and boosting immune activation through W>F substitutant events. This work proposes that EBV‐positive GC patients with mTOR/eIF4E hyperactivation may benefit from anti‐tumor immunotherapy.

Oxytocin (OT) is a posterior pituitary hormone that, in addition to its role in regulating childbirth and lactation, also exerts direct regulatory effects on the skeleton through peripheral OT and oxytocin receptor (OTR). Bone marrow mesenchymal stem cells (BMSCs), osteoblasts (OB), osteoclasts (OC), chondrocytes, and adipocytes all express OT and OTR. OT upregulates RUNX2, BMP2, ALP, and OCN, thereby enhancing the activity of BMSCs and promoting their differentiation towards OB rather than adipocytes. OT also directly regulates OPG/RANKL to inhibit adipocyte generation, increase the expression of SOX9 and COMP, and enhance chondrocyte differentiation. OB can secrete OT, exerting influence on the surrounding environment through autocrine and paracrine mechanisms. OT directly increases OC formation through the NκB/MAP kinase signaling pathway, inhibits osteoclast proliferation by triggering cytoplasmic Ca2+ release and nitric oxide synthesis, and has a dual regulatory effect on OCs. Under the stimulation of estrogen, OB synthesizes OT, amplifying the biological effects of estrogen and OT. Mediated by estrogen, the OT/OTR forms a feedforward loop with OB. Apart from estrogen, OT also interacts with arginine vasopressin (AVP), prostaglandins (PGE2), leptin, and adiponectin to regulate bone metabolism. This review summarizes recent research on the regulation of bone metabolism by OT and OTR, aiming to provide insights into their clinical applications and further research.

Microsatellite DNA (SSR) is extensively used as molecular markers in diverse fields, including molecular ecology, conservation biology, and molecular breeding. Nevertheless, the efficient and easy acquisition of high-quality SSR molecular markers for economically cultured marine animals remains a challenge. Holothuria leucospilota is an economically and ecologically important tropical sea cucumber. Recently, artificial breeding and cultivation of this species have been reported. However, there is still a lack of highly polymorphic SSR molecular markers for geographical population differentiation and genetic breeding. This study aims to develop and utilize SSR markers from genomic data to assess the genetic variation and population structure of H. leucospilota in the South China Sea. A comprehensive pipeline was created, integrating microsatellite discovery, primer design, and assessment into a single platform. Through this, 15 highly polymorphic microsatellite loci were identified and validated. The results revealed high genetic diversity and low genetic differentiation among H. leucospilota populations. Larval dispersal and ocean currents in the South China Sea were identified as the primary factors influencing genetic connectivity between populations. In addition, the artificial culture and releasing of H. leucospilota have influenced the genetic structure of their wild populations in the South China Sea. This study provides a pipeline for identifying SSR markers within genome data, and applies it to assess the genetic diversity and structure of H. leucospilota. The outcomes of this research are expected to be beneficial and applicable to the future aquaculture of tropical sea cucumbers.

ABSTRACT Objective: Tibial plateau fractures are common intra-articular fractures that pose classification and treatment challenges for orthopedic surgeons. Objective: This study examines the value of 3D printing for classifying and planning surgery for complex tibial plateau fractures. Methods: We reviewed 54 complex tibial plateau fractures treated at our hospital from January 2017 to January 2019. Patients underwent preoperative spiral CT scans, with DICOM data processed using Mimics software. 3D printing technology created accurate 1:1 scale models of the fractures. These models helped subdivide the fractures into seven types based on the tibial plateau's geometric planes. Surgical approaches and simulated operations, including fracture reduction and plate placement, were planned using these models. Results: The 3D models accurately depicted the direction and extent of fracture displacement and plateau collapse. They facilitated the preoperative planning, allowing for precise reconstruction strategies and matching intraoperative details with the pre-printed models. Post-surgery, the anatomical structure of the tibial plateau was significantly improved in all 54 cases. Conclusion: 3D printing effectively aids in the classification and preoperative planning of complex tibial plateau fractures, enhancing surgical outcomes and anatomical restoration. Level of Evidence IV, Prospective Study.

IntroductionCurrently, the development of new antiviral drugs against COVID-19 remains of significant importance. In traditional Chinese medicine, the herb Euphorbia fischeriana Steud is often used for antiviral treatment, yet its therapeutic effect against the COVID-19 has been scarcely studied. Therefore, this study focuses on the roots of E. fischeriana Steud, exploring its chemical composition, antiviral activity against COVID-19, and the underlying basis of its antiviral activity.MethodsIsolation and purification of phytochemicals from E. fischeriana Steud. The elucidation of their configurations was achieved through a comprehensive suite of 1D and 2D NMR spectroscopic analyses as well as X-ray diffraction. Performed cytopathic effect assays of SARS-CoV-2 using Vero E6 cells. Used molecular docking to screen for small molecule ligands with binding to SARS-CoV-2 RdRp. Microscale thermophoresis (MST) was used to determine the dissociation constant Kd.ResultsUltimately, nine new ent-atisane-type diterpenoid compounds were isolated from E. fischeriana Steud, named Eupfisenoids A-I (compounds 1-9). The compound of 1 was established as a C-19-degraded ent-atisane-type diterpenoid. During the evaluation of these compounds for their antiviral activity against COVID-19, compound 1 exhibited significant antiviral activity. Furthermore, with the aid of computer virtual screening and microscale thermophoresis (MST) technology, it was found that this compound could directly bind to the RNA-dependent RNA polymerase (RdRp, NSP12) of the COVID-19, a key enzyme in virus replication. This suggests that the compound inhibits virus replication by targeting RdRp.DiscussionThrough this research, not only has our understanding of the antiviral components and material basis of E. fischeriana Steud been enriched, but also the potential of atisane-type diterpenoid compounds as antiviral agents against COVID-19 has been discovered. The findings mentioned above will provide valuable insights for the development of drugs against COVID-19.

Introduction: Osteochondral repair poses a significant challenge due to its unique pathological mechanisms and complex repair processes, particularly in bacterial tissue conditions resulting from open injuries, infections, and surgical contamination. This study introduces a biomimetic honeycomb-like scaffold (Zn-AlgMA@Mg) designed for osteochondral repair. The scaffold consists of a dicalcium phosphate dihydrate (DCPD)-coated porous magnesium scaffold (DCPD Mg) embedded within a dual crosslinked sodium alginate hydrogel (Zn-AlgMA). This combination aims to synergistically exert antibacterial and osteochondral integrated repair properties.Methods: The Zn-AlgMA@Mg scaffold was fabricated by coating porous magnesium scaffolds with DCPD and embedding them within a dual crosslinked sodium alginate hydrogel. The structural and mechanical properties of the DCPD Mg scaffold were characterized using scanning electron microscopy (SEM) and mechanical testing. The microstructural features and hydrophilicity of Zn-AlgMA were assessed. In vitro studies were conducted to evaluate the controlled release of magnesium and zinc ions, as well as the scaffold’s osteogenic, chondrogenic, and antibacterial properties. Proteomic analysis was performed to elucidate the mechanism of osteochondral integrated repair. In vivo efficacy was evaluated using a rabbit full-thickness osteochondral defect model, with micro-CT evaluation, quantitative analysis, and histological staining (hematoxylin-eosin, Safranin-O, and Masson’s trichrome).Results: The DCPD Mg scaffold exhibited a uniform porous structure and superior mechanical properties. The Zn-AlgMA hydrogel displayed consistent microstructural features and enhanced hydrophilicity. The Zn-AlgMA@Mg scaffold provided controlled release of magnesium and zinc ions, promoting cell proliferation and vitality. In vitro studies demonstrated significant osteogenic and chondrogenic properties, as well as antibacterial efficacy. Proteomic analysis revealed the underlying mechanism of osteochondral integrated repair facilitated by the scaffold. Micro-CT evaluation and histological analysis confirmed successful osteochondral integration in the rabbit model.Discussion: The biomimetic honeycomb-like scaffold (Zn-AlgMA@Mg) demonstrated promising results for osteochondral repair, effectively addressing the challenges posed by bacterial tissue conditions. The scaffold’s ability to release magnesium and zinc ions in a controlled manner contributed to its significant osteogenic, chondrogenic, and antibacterial properties. Proteomic analysis provided insights into the scaffold’s mechanism of action, supporting its potential for integrated osteochondral regeneration. The successful in vivo results highlight the scaffold’s efficacy, making it a promising biomaterial for future applications in osteochondral repair.

Polystyrene nanoplastics (PS-NPs) have been reported to accumulate in the testes and constitute a new threat to reproductive health. However, the exact effects of PS-NPs exposure on testicular cells and the underlying mechanisms remain largely unknown. The C57BL/6 male mice were orally administered with PS-NPs (80 nm) at different dosages (0, 10, and 40 mg/kg/day) for 60 days, and GC-1 cells were treated with PS-NPs in this study. Enlarged seminiferous tubule lumens and a loose and vacuolated layer of spermatogenic cells were observed in PS-NPs-exposed mice. Spermatogenic cells which may be one of the target cells for this reproductive damage, were decreased in the mice from PS-NPs group. PS-NPs caused spermatogenic cells to undergo senescence, manifested as elevated SA-β-galactosidase activity and activated senescence-related signaling p53-p21/Rb-p16 pathways, and induced cell cycle arrest. Mechanistically, Gene Ontology (GO) enrichment suggested the key role of reactive oxygen species (ROS) in PS-NPs-induced spermatogenic cell senescence, and this result was confirmed by measuring ROS levels. Moreover, ROS inhibition partially attenuated the senescence phenotype of spermatogenic cells and DNA damage. Using the male health atlas (MHA) database, Sirt1 was filtrated as the critical molecule in the regulation of testicular senescence. PS-NPs induced overexpression of the main ROS generator Nox2, downregulated Sirt1, increased p53 and acetylated p53 in vivo and in vitro, whereas these disturbances were partially restored by pterostilbene. In addition, pterostilbene intervention significantly alleviated the PS-NPs-induced spermatogenic cell senescence and attenuated ROS burst. Collectively, our study reveals that PS-NPs exposure can trigger spermatogenic cell senescence mediated by p53-p21/Rb-p16 signaling by regulating the Sirt1/ROS axis. Importantly, pterostilbene intervention may be a promising strategy to alleviate this damage.