ObjectiveTo investigate the effect and mechanism of cordycepin in inhibiting fat infiltration after rotator cuff injuries in rats by regulating the Wnt/β-catenin signaling pathway， providing a theoretical basis for clinical treatment of rotator cuff injuries. MethodsFifty SPF-grade female SD rats were used in this study， with 10 randomly selected as the blank group. A rotator cuff injury repair model was established by supraspinatus tendon and suprascapular nerve compression. The successfully modeled rats were randomized into model and low-dose （20 mg·kg^-1）， medium-dose （40 mg·kg^-1）， and high-dose （80 mg·kg^-1） cordycepin groups. After 6 weeks of treatment， the gait analysis was performed to assess the limb function in rats. Oil red O staining and Masson staining were employed to observe pathological changes in the muscle tissue. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of interleukin-1β （IL-1β）， interleukin-6 （IL-6）， and tumor necrosis factor-α （TNF-α） in the serum. Immunohistochemistry （IHC） was employed to detect the expression of peroxisome proliferator-activated receptor γ （PPARγ） and CCAAT/enhancer-binding protein α （C/EBPα）， which are markers of adipogenesis. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were employed to determine the mRNA and protein levels， respectively， of Wnt3a， Wnt10b， and β-catenin. ResultsCompared with the blank group， the model group showed decreases in stride length and paw print area （P<0.01）， an increase in ratio of wet muscle mass reduction and a decrease in muscle fiber cross-sectional area （P<0.05）， and decreased ratios of fat infiltration area and collagen fiber area （P<0.01）. Additionally， the model group showed elevated levels of IL-1β， IL-6， and TNF-α （P<0.05）， up-regulated protein levels of PPARγ and C/EBPα （P<0.01）， and down-regulated mRNA and protein levels of Wnt3a， Wnt10b， and β-catenin （P<0.05， P<0.01）. Compared with the model group， the low-， medium-， and high-dose cordycepin groups showed increases in stride length and paw print area （P<0.01）， a decrease in ratio of wet muscle mass reduction and an increase in muscle fiber cross-sectional area （P<0.05）， and increases in ratios of fat infiltration area and collagen fiber area （P<0.05， P<0.01）. In addition， cordycepin lowered the serum levels of IL-1β， IL-6， and TNF-α （P<0.05， P<0.01）， down-regulated the protein levels of PPARγ and C/EBPα （P<0.01）， and up-regulated the mRNA and protein levels of Wnt3a， Wnt10b， and β-catenin （P<0.05， P<0.01）. ConclusionCordycepin can improve the limb function， alleviate rotator cuff muscle atrophy， fat infiltration， and fibrosis， and inhibit inflammation in rats by regulating the Wnt/β-catenin signaling pathway.

Houpo Qiwutang originated from the Synopsis of the Golden Chamber， and it consists of seven medicines： Magnoliae Officinalis Cortex， Rhei Radix et Rhizoma， Aurantii Fructus Immaturus， Cinnamomi Ramulus， Zingiberis Rhizoma Recens， Glycyrrhizae Radix et Rhizoma， and Jujubae Fructus. It is a basic formula for the treatment of abdominal fullness. Through the bibliometric method， the historical history， drug base， preparation and dosage， decoction method， and ancient and modern applications of Houpu Qiwu Tang were analyzed by means of textual research. The research finds that Houpu Qiwu Tang has been passed down through the generations in an orderly manner with fewer changes. The drug base of this formula is basically clear， and the base of Magnoliae Officinalis Cortex， Rhei Radix et Rhizoma， Cinnamomi Ramulus， Zingiberis Rhizoma Recens， and Jujubae Fructus is consistent with the 2020 edition of Chinese Pharmacopoeia. The mainstream base of Aurantii Fructus Immaturus is the dried young fruit of Citrus aurantium of Rutaceae family， and the historical mainstream base of Glycyrrhizae Radix et Rhizoma is the dried root of Glycyrrhiza uralensis of Leguminosae family. The modern dosage of this formula is 110.40 g of Magnoliae Officinalis Cortex， 41.40 g of Rhei Radix et Rhizoma， 69 g of Aurantii Fructus Immaturus， 27.60 g of Cinnamomi Ramulus， 69 g of Zingiberis Rhizoma Recens， 41.40 g of Glycyrrhizae Radix et Rhizoma， and 30 g of Jujubae Fructus. In addition， the decoction method is to add 2 000 mL of water with the above seven flavors of the medicine， boil it to 800 mL， and then take 160 mL in a warm state each time. The amount of the medicine taken for each time is 22.08 g of Magnoliae Officinalis Cortex， 8.28 g of Rhei Radix et Rhizoma， 13.80 g of Aurantii Fructus Immaturus， 5.52 g of Cinnamomi Ramulus， 13.80 g of Zingiberis Rhizoma Recens， 8.28 g of Glycyrrhizae Radix et Rhizoma， and 6 g of Jujubae Fructus. The modern application of this formula involves the digestive system， respiratory system， and urinary system. It is more advantageous in digestive system diseases such as early postoperative inflammatory bowel obstruction， functional dyspepsia， gastric pain， functional abdominal distension， and gastric reflux esophagitis. By comprehensively examining the key information of Houpu Qiwu Tang， this paper aims to provide literature support for the development and clinical application of this formula.

BACKGROUND:Ursolic acid can promote the directed differentiation of bone marrow mesenchymal stem cells into osteoblasts.However,there are few reports on whether ursolic acid has osteogenic effect on human periodontal ligament stem cells. OBJECTIVE:To investigate the effect of ursolic acid on proliferation and osteogenic differentiation of human periodontal ligament stem cells. METHODS:The human periodontal ligament stem cells were isolated and cultured.Passage 3 cells were selected and treated with ordinary medium containing different concentrations(0,1,2,4,6,8 μmol/L)of ursolic acid.After intervention for 1,3,5,7 days,the cell proliferation was detected by CCK-8 assay and the appropriate intervention concentration was screened.Passage 3 human periodontal ligament stem cells were treated with osteogenic induction solution containing 0,1,2,4 μmol/L ursolic acid,respectively.After 7 days of intervention,the mRNA expressions of alkaline phosphatase,Runx2,and osteocalcin were detected by qRT-PCR.After 14 days of intervention,the formation of mineralized nodules was observed by alizarin red staining.Passage 3 human periodontal ligament stem cells were taken and the control group was added with osteogenic induction solution;the ursolic acid group and the antagonist group were added with osteogenic induction solution containing ursolic acid(2 μmol/L)and the bone morphogenetic protein signaling pathway antagonist Noggin,respectively.The ursolic acid+antagonist group was added with osteogenic induction solution containing ursolic acid(2 μmol/L)and Noggin,the inhibitor of bone morphogenetic protein signaling pathway,and cultured for 7 days.qRT-PCR and western blot assay were used to detect the mRNA and protein expressions of bone morphogenetic protein 2,Smad1,osteopontin,and Runx2. RESULTS AND CONCLUSION:(1)1,2,4 μmol/L ursolic acid could promote the proliferation of human periodontal ligament stem cells.6,8 μmol/L ursolic acid could inhibit the proliferation of human periodontal ligament stem cells,and 1,2,4 μmol/L ursolic acid was selected to intervene in subsequent experiments.(2)Compared with 0 μmol/L,1,2,4 μmol/L ursolic acid could promote the expression of alkaline phosphatase,Runx2,and osteocalcin mRNA and the formation of mineralized nodules(P<0.05),and the effect of 2 μmol/L ursolic acid was the most significant.(3)Compared with the control group,the mRNA and protein expressions of bone morphogenetic protein 2,Smad1,osteopontin,and Runx2 in the ursolic acid group were increased(P<0.05),while mRNA and protein expressions of the above indexes were decreased in the antagonist group(P<0.05).Compared with the ursolic acid group,mRNA and protein expressions of above indexes were decreased in ursolic acid+antagonist group(P<0.05).(4)The results indicate that ursolic acid promotes osteogenic differentiation of human periodontal ligament stem cells through bone morphogenetic protein signaling pathway.

BACKGROUND:Parkinson's disease has the main pathological changes in the midbrain,especially in the dense substantia nigra,leading to impaired motor and non-motor function in patients.At present,research is limited by cellular heterogeneity,and its pathogenesis still needs to be further elucidated.In recent years,single-cell RNA sequencing(scRNA-seq)has gradually been applied in neurodegenerative diseases,which is of great significance for understanding intercellular heterogeneity,disease development mechanisms,and treatment strategies. OBJECTIVE:To review the research progress of scRNA-seq technology applied to Parkinson's disease in recent years,providing a theoretical basis for the application of scRNA-seq in the treatment and diagnosis of Parkinson's disease. METHODS:The first author used a computer system to search for relevant literature in the CNKI,WanFang,PubMed,and Web of Science databases,with the Chinese search terms"single-cell RNA sequencing,Parkinson's disease,cell heterogeneity,cell subtypes,dopaminergic neurons,glial cells"and English search terms"single-cell RNA seq,Parkinson disease,heterogenicity,subtypes,dopaminergic neurons,glial cells."71 articles were ultimately included for review and analysis. RESULTS AND CONCLUSION:(1)scRNA-seq is a high-throughput experimental technique that utilizes RNA sequencing at the single-cell level to quantify gene expression profiles in specific cell populations,revealing cellular mysteries at the molecular level.Compared with traditional sequencing techniques,scRNA-seq technology is used to reveal the diversity of cell types and changes in specific gene expression in complex tissues under various physiological and pathological conditions through automatic clustering analysis of cell transcriptome.(2)By using scRNA-seq,the development process of dopaminergic neurons and the unique functional characteristics of various cell subtypes are elucidated,in order to better understand potential therapeutic molecular targets.(3)The use of scRNA-seq analysis has improved our understanding of the response of Parkinson's disease glial cells,enabling us to comprehensively map and characterize different cell type populations,identify specific glial cell subpopulations related to neurodegeneration,and draw valuable single cell maps as reference data for future research.(4)The application of scRNA-seq to detect embryonic mice and stem cells will help improve the in vitro differentiation protocol and quality control of cell therapy,as well as evaluate the overall cell quality and developmental stage of dopaminergic neurons derived from stem cells.

BACKGROUND:Muscle aging is closely related to various epigenetic changes,and exercise has a certain regulatory effect on these epigenetic changes.However,the specific mechanism is not fully understood. OBJECTIVE:To review the epigenetic mechanisms of skeletal muscle and how exercise can improve skeletal muscle aging and promote adaptive changes in muscle through these epigenetic mechanisms,aiming to provide a more comprehensive understanding of skeletal muscle aging and disease mechanisms. METHODS:During the period from June 1st to August 1st,2023,literature searches were conducted for relevant literature published from database inception to August 2023 in databases including Web of Science,PubMed,CNKI,WanFang,and VIP.The search terms used included"skeletal muscle,""muscle,""aging,""older adult,""aging,""exercise,""physical exercise,""epigenetic,"and"epigenetics"in Chinese as well as"skeletal muscle,muscle,aging,older adult,senescence,age,exercise,sports,physical activity,epigenetic,epigenetics"in English.Boolean logic operators were used to connect the search terms for retrieval,and corresponding strategies were developed.According to the predetermined inclusion and exclusion criteria,70 eligible articles were selected. RESULTS AND CONCLUSION:Epigenetics refers to the phenomenon where gene expression and function are regulated without changes in gene sequence,and epigenetic changes in skeletal muscle are an important field.The epigenetic mechanisms of skeletal muscle play an important role in muscle aging,mainly involving DNA methylation,histone modification,regulation of non-coding RNAs,chromatin remodeling,changes in mitochondrial function and expression changes of aging-related genes.Exercise significantly regulates the epigenetics of skeletal muscle,including promoting DNA methylation,muscle histone modification,regulating miRNA expression,and regulating lncRNA expression,regulating muscle factors(such as interleukin-6),regulating mitochondrial function(such as peroxisome proliferators-activated receptors γ co-activator 1α).Future studies are recommended for long-term,cross-diverse population-based exercise interventions;the application of multi-omics techniques such as proteomics and metabolomics;strengthening the understanding of epigenetic changes at the single-cell level;cross-species comparative studies as well as human clinical trials for the translation of animal model findings to humans;strategies for combining exercise and pharmacological interventions to assess their synergistic effects;and epigenetic studies of crosstalk interactions between skeletal muscle and different organs.

BACKGROUND:The treatment of early knee osteoarthritis can be achieved through two knee preservation treatments:Unicondylar knee arthroplasty and high tibial osteotomy.However,further exploration is needed to determine whether there are differences in knee joint recovery between the two knee preservation surgeries at different stages after surgery. OBJECTIVE:To compare the efficacy and related complications of unicondylar knee arthroplasty and high tibial osteotomy in the treatment of varus osteoarthropathy of the knee,and to provide a reference for clinical decision. METHODS:A total of 103 patients with varus osteoarthritis of the knee underwent surgical treatment in the Affiliated Hospital of Nantong University from September 2018 to September 2022 were selected.Among them,86 patients were followed up for more than 1 year.According to different surgical methods,the patients were divided into unicondylar knee arthroplasty group(49 cases)and high tibial osteotomy group(37 cases).Knee function,pain,and line of force correction were evaluated before surgery,4 weeks,3 months,6 months,and 1 year after surgery in both groups.Hospital for special surgery knee score,functional score of Western Ontario and McMaster Universities Osteoarthritis Index,changes of lateral space of the knee joint,range of motion,proprioception(position sense),and postoperative activity recovery speed were evaluated comprehensively. RESULTS AND CONCLUSION:(1)There were no significant differences in preoperative hospital for special surgery knee score,Western Ontario and McMaster Universities Osteoarthritis Index score and lateral knee compartment size between the two groups.(2)The hospital for special surgery knee score of patients undergoing unicondylar knee arthroplasty was better than that of patients undergoing high tibial osteotomy within 4 weeks after surgery(P<0.05).At 3 and 6 months after surgery,compared with the improvement of the two groups,the hospital for special surgery knee score in the unicondylar knee arthroplasty group was lower than that in the high tibial osteotomy group,and the difference was significant(P<0.05).The range of motion flexion value and position perception of patients undergoing high tibial osteotomy were significantly better than those undergoing unicondylar knee arthroplasty 6 months after surgery(P<0.05).(3)The unicondylar knee arthroplasty group was better than the high tibial osteotomy group in terms of the speed of knee movement recovery(P<0.05).(4)However,there was no significant difference between the two groups in the change of hospital for special surgery knee score,range of motion,and the width of lateral knee space during 1-year follow-up.(5)All patients were followed up for more than 1 year,and no adverse complications were found during the follow-up.(6)It is indicated that the short-term effect of knee functional recovery in patients with high tibial osteotomy is better than that in patients with unicondylar knee arthroplasty,but there is no significant difference in medium-and long-term efficacy between the two kinds of surgery for medial knee arthritis.

BACKGROUND:At present,osteoarthritis has become a major disease affecting the quality of life of the elderly,and the therapeutic effect is poor,often focusing on preventing the disease process,and the pathogenesis of osteoarthritis is still not fully understood.Bioinformatics analysis was carried out to explore the main pathogenesis of osteoarthritis and related mechanisms of gene coding regulation. OBJECTIVE:To screen core differential genes with a major role in osteoarthritis by gene expression profiling. METHODS:Datasets were downloaded from the Gene Expression Omnibus(GEO):GSE114007,GSE117999,and GSE129147.Differential genes in the GSE114007 and GSE117999 data collections were screened using R software,performing differential genes to weighted gene co-expression network analysis.The module genes most relevant to osteoarthritis were selected to perform protein interaction analysis.Candidate core genes were selected using the cytocape software.The candidate core genes were subsequently subjected to least absolute shrinkage and selection operator regression and COX analysis to identify the core genes with a key role in osteoarthritis.The accuracy of the core genes was validated using an external dataset,GSE129147. RESULTS AND CONCLUSION:(1)A total of 477 differential genes were identified,265 differential genes associated with osteoarthritis were obtained by weighted gene co-expression network analysis,and 8 candidate core genes were identified.The least absolute shrinkage and selection operator regression analysis finally yielded a differential gene ASPM with core value that was externally validated.(2)It is concluded that abnormal gene ASPM expression screened by bioinformatics plays a key central role in osteoarthritis.

BACKGROUND:Research on carbon nanomaterials in the biomedical field is booming,and related scientific research results are increasing year by year.However,visualization analysis of the annual number of publications,the research status of countries,institutions,authors,and research hotspots and trends in this field is relatively scarce. OBJECTIVE:To present the research status of carbon nanomaterials in biomedical field,reveal the main research subjects,explore the research hotspots and development trends,and provide a reference for the future development of this field. METHODS:The core data set of Web of Science was used as the literature source to search the relevant researches on carbon nanomaterials in the biomedical field from 2012 to 2023.The knowledge map was generated by using Citespace software with countries,institutions,authors,keywords,and co-citations as nodes and for visualization analysis. RESULTS AND CONCLUSION:(1)A total of 2 932 papers were included in this study.In the medical field,carbon nanomaterials had a large number of papers and a fast growth rate.The United States has a large number of papers;China is an emerging force in this field,although the number of papers is the largest,but the level of research and influence need to be improved.The Chinese Academy of Sciences is the largest cooperative network institution,which mainly targets domestic institutions and lacks cooperation with well-known foreign institutions.(2)Keyword analysis displays that the green synthesis method and application of displaying carbon points have been the focus of research,followed by the new method of combining carbon nanomaterials with cancer phototherapy and immunotherapy,the key direction of future research.(3)The dynamic development trend of co-citations suggests that tissue engineering is a hot research topic of carbon nanomaterials in the field of biomedicine,mainly including the research of carbon nanomaterials for the repair and regeneration of heart and nerve tissue and as a bio-ink additive for 3D and 4D bioprinting.(4)In the future,with the development of the biomedical field in the direction of precision and treatment,researchers should speed up the creation of carbon-based systems formed by the combination of scientific and effective carbon nanomaterials with science and technology,new polymers or organic molecules,and new therapeutic methods,so as to give full play to the maximum effect of carbon nanomaterials.

BACKGROUND:Magnetic nanomaterials have biological activities such as promoting osteogenic differentiation of stem cells and inhibiting osteoclast formation,and can effectively promote the healing of injured bone tissue under the synergistic effect of magnetic fields.They have a very broad application prospect in bone injury repair. OBJECTIVE:To review the mechanism of magnetic nanomaterials and magnetic fields promoting bone repair,as well as their research progress in the field of bone injury repair. METHODS:Relevant literature search was conducted in PubMed and Web of Science databases with the search terms"magnetic nanomaterials,magnetic field,bone repair,bone tissue engineering,stem cell,osteoblast,osteoclast."The time limit of literature search was from 2003 to 2023,which was screened and analyzed.Some classic articles were manually retrieved,and 98 articles were finally included for analysis. RESULTS AND CONCLUSION:(1)Magnetic nanomaterials have biological effects such as promoting osteoblast differentiation,inhibiting osteoclast formation and regulating the immune microenvironment.In addition,magnetic nanomaterials can regulate the physicochemical properties of tissue engineering scaffolds,such as mechanical properties and surface morphology,and endowed with magnetic properties,which is conducive to the regulation of the adhesion,proliferation and osteogenic differentiation of stem cells.(2)The magnetic field has the ability to regulate multiple cell signaling pathways to promote osteoblast differentiation,inhibit osteoclast formation,stimulate angiogenesis and other biological effects,thus accelerating the healing of damaged bone tissue.(3)The joint application of magnetic nanomaterials and magnetic field accelerates the repair of bone damage by activating mechanotransduction,increasing the content of intracellular magnetic nanoparticles,and enhancing the effect of micro-magnetic field,which provides a new idea for the research of bone tissue engineering.(4)Magnetic field has demonstrated definite efficacy in the treatment of clinical fractures,osteoporosis,and osteoarthritis diseases,which is beneficial for bone tissue growth,reducing bone loss,alleviating pain,and improving the quality of life of patients.(5)Magnetic nanomaterials and magnetic fields have great potential for application in bone damage repair and regeneration,but the interaction mechanism between magnetic nanomaterials,magnetic fields,and cells has not been fully elucidated.Moreover,the key parameters of magnetic fields that regulate intracellular molecular events,including the type,intensity,frequency,duration,and mode of the magnetic field,as well as the precise biological effects of a specific magnetic field on osteoblasts and the underlying mechanisms,have yet to be defined.(6)Further attention needs to be paid to the effects on osteoclasts,nerves,blood vessels,and immune cells in the microenvironment of damaged tissues.Finally,the safety of magnetic materials for human use is yet to be systematically studied in terms of their distribution,metabolism,and acute and chronic toxicities.

BACKGROUND:Gradient artificial bone repair scaffolds can mimic unique anatomical features in musculoskeletal tissues,showing great potential for repairing injured musculoskeletal tissues. OBJECTIVE:To review the latest research advances in gradient artificial bone repair scaffolds for tissue engineering in the musculoskeletal system and describe their advantages and fabrication strategies. METHODS:The first author of the article searched the Web of Science and PubMed databases for articles published from 2000 to 2023 with search terms"gradient,bone regeneration,scaffold".Finally,76 papers were analyzed and summarized after the screening. RESULTS AND CONCLUSION:(1)As an important means of efficient and high-quality repair of skeletal system tissues,gradient artificial bone repair scaffolds are currently designed bionically for the natural gradient characteristics of bone tissue,bone-cartilage,and tendon-bone tissue.These scaffolds can mimic the extracellular matrix of native tissues to a certain extent in terms of structure and composition,thus promoting cell adhesion,migration,proliferation,differentiation,and regenerative recovery of damaged tissues to their native state.(2)Advanced manufacturing technology provides more possibilities for gradient artificial bone repair scaffold preparation:Gradient electrospun fiber scaffolds constructed by spatially differentiated fiber arrangement and loading of biologically active substances have been developed;gradient 3D printed scaffolds fabricated by layered stacking,graded porosity,and bio-3D printing technology;gradient hydrogel scaffolds fabricated by in-situ layered injections,simple layer-by-layer stacking,and freeze-drying method;and in addition,there are also scaffolds made by other modalities or multi-method coupling.These scaffolds have demonstrated good biocompatibility in vitro experiments,were able to accelerate tissue regeneration in small animal tests,and were observed to have significantly improved histological structure.(3)The currently developed gradient artificial bone repair scaffolds have problems such as mismatch of gradient scales,unclear material-tissue interactions,and side effects caused by degradation products,which need to be further optimized by combining the strengths of related disciplines and clinical needs in the future.