BACKGROUND:Bone relies on the close connection between blood vessels and bone cells to maintain its integrity.Bones are in a physiologically hypoxic environment.Therefore,the study of angiogenesis and osteogenesis in hypoxic environment is closer to the microenvironment in vivo. OBJECTIVE:To explore the influence of Wenshen Tongluo Zhitong(WSTLZT)formula on H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell co-culture system in hypoxia environment and its related mechanism. METHODS:Enzyme digestion method and flow sorting technique were used to isolate and identify H-type bone microvascular endothelial cells.Mouse bone marrow mesenchymal stem cells were isolated and obtained by bone marrow adhesion method.H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell hypoxic co-culture system was established using Transwell chamber and anoxic culture workstation.WSTLZT formula powder was used to intervene in each group at a mass concentration of 50 and 100 μg/mL.The angiogenic function of H-type bone microvascular endothelial cells in the co-culture system was evaluated by scratch migration test and tube formation test.The osteogenic differentiation ability of bone marrow mesenchymal stem cells in the co-cultured system was evaluated by alkaline phosphatase staining and alizarin red staining.The protein and mRNA expression changes of PDGF/PI3K/AKT signal axis related molecules in H-type bone microvascular endothelial cells in the co-cultured system were detected by Western Blotting and q-PCR,respectively. RESULTS AND CONCLUSION:(1)Compared with the normal oxygen group,the scratch mobility and new blood vessel length of H-type bone microvascular endothelial cells were significantly higher(P<0.05);the osteogenic differentiation capacity of bone marrow mesenchymal stem cells was higher(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular protein and mRNA increased(P<0.05)in the hypoxia group.(2)Compared with the hypoxia group,scratch mobility and new blood vessel length were significantly increased in the H-type bone microvascular endothelial cells(P<0.05);bone marrow mesenchymal stem cells had stronger osteogenic function(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular proteins and mRNA further increased(P<0.05)after treatment with different dose concentrations of WSTLZT formula.These findings conclude that H-type angiogenesis and osteogenesis under hypoxia may be related to the PDGF/PI3K/AKT signaling axis,and WSTLZT formula may promote H-type vasculo-dependent bone formation by activating the PDGF/PI3K/AKT signaling axis,thereby preventing and treating osteoporosis.

BACKGROUND:Psoralen has a strong anti-osteoporotic activity and may have a restorative effect on chemotherapy-induced osteoporosis. OBJECTIVE:To explore the restorative effect of psoralen on the osteogenic differentiation of bone marrow mesenchymal stem cells in mice inhibited by cyclophosphamide and its mechanism. METHODS:C57BL/6 mouse bone marrow mesenchymal stem cells were isolated and cultured.Effect of psoralen on viability of bone marrow mesenchymal stem cells was detected by MTT assay.Osteogenic induction combined with alkaline phosphatase staining was used to determine the optimal dose of psoralen to restore the osteogenic differentiation of bone marrow mesenchymal stem cells inhibited by cyclophosphamide.The mRNA expression levels of Runx2,alkaline phosphatase,Osteocalcin,osteoprotegerin,and Wnt/β-catenin signaling pathway-related genes Wnt1,Wnt4,Wnt10b,β-catenin,and c-MYC were measured by RT-qPCR at different time points under the intervention with psoralen.The protein expression of osteogenic specific transcription factor Runx2 and Wnt/β-catenin signaling pathway related genes Active β-catenin,DKK1,c-MYC,and Cyclin D1 was determined by western blot assay at different time points under the intervention with psoralen. RESULTS AND CONCLUSION:(1)There was no significant effect of different concentrations of psoralen on the viability of bone marrow mesenchymal stem cells.The best recovery of the inhibition of osteogenic differentiation of bone marrow mesenchymal stem cells caused by cyclophosphamide was under the intervention of psoralen at a concentration of 200 μmol/L.(2)Psoralen reversed the reduction in osteogenic differentiation marker genes Runx2,alkaline phosphatase,Osteocalcin and osteoprotegerin mRNA expression and Runx2 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(3)Psoralen reversed the decrease in Wnt/β-catenin pathway-related genes Wnt4,β-catenin,c-MYC mRNA and Active β-catenin,c-MYC,and Cyclin D1 protein expression and the increase in DKK1 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(4)The results showed that cyclophosphamide inhibited osteogenic differentiation of bone marrow mesenchymal stem cells in mice,and psoralen had a restorative effect on it.The best intervention effect was achieved at a concentration of 200 μmol/L psoralen,and this protective effect might be related to the activation of Wnt4/β-catenin signaling pathway by psoralen.

BACKGROUND:Prolyl hydroxylase domain 2(PHD2)inhibitors can regulate bone metabolism and relieve osteoporosis in ovariectomized rats.cpd17 is a small molecule oral PHD2 inhibitor newly developed by China Pharmaceutical University.It is effective in the treatment of renal anemia with few side effects,but its effect on bone formation and bone resorption is still unclear. OBJECTIVE:To investigate the effects of cpd17 on mouse osteogenic precursor cells. METHODS:Osteogenic precursor cells were treated with cpd17.Alkaline phosphatase activity and extracellular matrix mineralization were measured,and the expression levels of osteogenesis-and osteoclastogenesis-related markers,as well as PHD2 and hypoxia-inducible factor 1α,were detected.After inhibition of the hypoxia-inducible factor 1α pathway using LW6(a hypoxia-inducible factor 1α pathway inhibitor),alkaline phosphatase activity and extracellular matrix mineralization were detected again,as well as the expression levels of osteogenesis-and osteoclastogenesis-related markers,PHD2 and hypoxia-inducible factor 1α. RESULTS AND CONCLUSION:cpd17 significantly enhanced alkaline phosphatase activity and extracellular matrix mineralization,up-regulated the expression of osteogenesis-related markers,down-regulated the expression of osteoclastogenesis-related markers,up-regulated the expression of hypoxia-inducible factor 1α,down-regulate the expression of PHD2.However,cpd17's effects were significantly attenuated by LW6.To conclude,the PHD2 inhibitor cpd17 promotes osteogenic differentiation and inhibits osteoclastic differentiation through activation of the hypoxia-inducible factor 1α signaling pathway.

BACKGROUND:Differentially expressed RNA-binding proteins in the intervertebral disc plays a key role in intervertebral disc degeneration,and decreased levels of the RNA-binding protein KRT18 are associated with degenerative disc disease,but its specific role in the nucleus pulposus cells has not yet been fully determined. OBJECTIVE:To investigate the interaction of KRT18 with mRNA and long non-coding RNA on nucleus pulposus cells of the intervertebral disc and its mechanism. METHODS:Normal and degenerated nucleus pulposus cells were obtained from nucleus pulposus samples of patients undergoing interbody fusion for lumbar fracture or intervertebral disc degeneration.iRIP-seq,functional enrichment analysis,and DNA microarray analysis were performed to identify the mRNA and long non-coding RNA binding with KRT18.Subsequently,KRT18 was knocked down in nucleus pulposus cells based on the analysis results,and the expression levels of related genes were detected at the protein and RNA levels through protein immunoblotting and qRT-PCR,respectively. RESULTS AND CONCLUSION:Through iRIP-seq analysis,we identified abundant KRT18 binding sites within the GUAAUC and AGCCUC sequences,indicating that KRT18 may be involved in regulating RNA transcription,translation,stability or play a role in cell signaling pathways.It can stably bind to mature mRNA,among which highly expressed genes include CRLF1,IGFBP4,etc.At the same time,the peak genes of long non-coding RNA binding with it include SNHG25,SNHG12,NEAT1,USP32,EIF4A2 and CDH4.Most of these genes are involved in various biological processes such as apoptosis and inflammation,and can mediate related pathways of extracellular matrix metabolism.KRT18 can regulate their stability,transport,translation,splicing and other functions,thus affecting gene expression and cell function.We further verified through experiments the knockdown of KRT18 in nucleus pulposus cells,and found that the level of extracellular matrix metabolism was inhibited and unbalanced,resulting in intervertebral disc degeneration in vitro.This study investigated the regulatory mechanism of KRT18 from the perspective of its binding with mRNA and long non-coding RNA for the first time,and speculated the potential function of KRT18 in the pathogenesis of intervertebral disc degeneration,laying a foundation for future research on the key functions of KRT18.

BACKGROUND:Osteoarthritis is now considered a metabolic disease.Previous studies have shown that glycolysis plays an important role in the occurrence and development of osteoarthritis.Compound 3k,as a novel small molecule inhibitor of glycolysis,has anti-inflammatory and anti-tumor effects.Therefore,it can target glycolysis and is expected to provide new ideas for the treatment of osteoarthritis. OBJECTIVE:To explore the role of Compound 3k in osteoarthritis caused by glycolytic overactivity based on the hypoxia-inducible factor 1 alpha(HIF-1α)/reactive oxygen species(ROS)pathway. METHODS:ATDC5 chondroblasts at logarithmic growth phase were taken to induce osteoarthritis in an in vitro cellular model by the action of 10 ng/mL interleukin-1β for 24 hours.The cytotoxicity of Compound 3k at different concentrations(0.25,0.5,1,2.5,5,10,15 μmol/L)was detected by cell counting kit-8 assay,and the appropriate concentrations were selected for the subsequent experiments.The chondrocytes were randomly divided into control,model and treatment groups.The model group was induced with 10 ng/mL interleukin 1β,and the treatment group was pre-stimulated with Compound 3k for 2 hours and then co-cultured with interleukin 1β.The proliferation of the cells in each group was detected by the cell counting kit-8 assay;the inflammatory level of the cells in each group was detected by the ELISA kit;the ROS,extracellular lactate and glucose contents were detected using the kit;qRT-PCR and western blot were used to detect the levels of related inflammatory factors,interleukin-6 and tumor necrosis factor-α,glycolysis-related genes glucose transporter protein-1,glyceraldehyde 3-phosphate dehydrogenase,monocarboxylate transporter protein-1 and HIF-1α. RESULTS AND CONCLUSION:Compared with the control group,the model group showed a decrease in cell proliferative activity,active glycolysis level,manifested by an increase in extracellular lactate content(P<0.001)and a decrease in glucose content(P<0.001),interleukin-6(P<0.000 1)and tumor necrosis factor-α(P<0.001).The expression levels of glycolysis-related genes glucose transporter protein-1(P<0.001),glyceraldehyde 3-phosphate dehydrogenase(P<0.001),monocarboxylic acid transporter protein-1(P<0.001)and HIF-1α(P<0.001)in the model group were all up-regulated,accompanied by oxidative stress and overproduction of ROS.Compared with the model group,Compound 3k treatment effectively increased cell proliferation activity and inhibited the level of overactive glycolysis(P<0.001),while suppressing the expression of genes related to inflammation(P<0.001)and glycolysis in osteoarthritic chondrocytes,inhibiting oxidative stress,downregulating the expression level of HIF-1α(P<0.000 1)and decreasing the content of ROS.To conclude,Compound 3k inhibits interleukin-1β induced chondrocyte inflammation,and its mechanism may be related to glycolysis and HIF-1α/ROS mediated oxidative stress.

BACKGROUND:Dysfunction of macrophage efferocytosis can induce local and systemic inflammatory damage and is associated with a variety of obesity-related metabolic diseases.Moreover,compounds targeting efferocytosis have shown good therapeutic effects. OBJECTIVE:By reviewing the effects of obesity on macrophage efferocytosis,to analyze the key mechanism by which obesity inhibits efferocytosis,to summarize the research progress in compounds targeting efferocytosis to treat obesity-related metabolic diseases,so as to provide new ideas for fully understanding efferocytosis and its relationship with metabolic diseases,aiming to provide new strategies for disease prevention and treatment. METHODS:The English search terms were"efferocytosis,metabolism,obesity,obese,atherosclerosis,non-alcoholic steatohepatitis,neurodegeneration,tumor,osteoarthritis,diabetes,compound,medicine,treatment,"which were used for literature retrieval in PubMed and Web of Science.The Chinese search term was"efferocytosis,"which was used for literature retrieval in CNKI,VIP and WanFang datebases.Ninety-nine papers were finally included in the review analysis after a rigorous screening process. RESULTS AND CONCLUSION:In the process of efferocytosis,the"Find me"and"Eat me"processes involving a large number of apoptotic cell derived factors are mainly regulated by apoptotic cells.The efferocytosis factor involved in cytoskeletal remodeling and digestion are mainly derived from macrophages,which are crucial for efferocytosis activity.These results suggest that the"Find me"and"Eat me"factors mainly reflect the condition of apoptosis,and it is more scientific to select the expression of factors involved in cytoskeletal remodeling and digestion when evaluating the efferocytosis activity of macrophages.Obesity inhibits efferocytosis,and shows an inhibitory effect on most digestive factors,but has a stress-induced activation effect on most"Find me,""Eat me"and cytoskeletal recombination factors,which further indicates the decisive effect of digestive stage on efferocytosis and suggests that it is not reliable for some studies to evaluate the efferocytosis based on the increased expression of"Find me"and"Eat me"factors.Targeting cytokines in the digestive phase may be more effective when discussing future intervention strategies targeting macrophages efferocytosis.The efferocytosis activators of macrophages are effective in the treatment of various metabolic diseases,but the efferocytosis inhibitors in tumor tissue show good anticancer effects,suggesting that the role of efferocytosis should be rationally evaluated according to the characteristics of tissue inflammation.Efferocytosis is a relatively new concept proposed in 2003,with a short research history and complex efferocytosis factors.Current studies on obesity and efferocytosis only involve a tip of the iceberg and most of them are at a superficial level and a large number of scientific experiments are needed to further validate the mechanisms.

BACKGROUND:There is still no consensus on the optimal internal fixation for the treatment of Pauwels Ⅲ femoral neck fracture,and most of the related finite element analyses have been performed using a single simplified loading condition,and the biomechanical properties of commonly used internal fixation devices need to be further investigated. OBJECTIVE:To analyze the biomechanical characteristics of Pauwels Ⅲ femoral neck fractures treated with cannulated compression screw,dynamic hip screw,and femoral neck system by finite element method under different loading conditions of single-leg standing loads and sideways fall loads. METHODS:The DICOM data of healthy adult femur were obtained by CT scanning,imported into Mimics 15.0 software to obtain the rough model of bone tissue.The data exported from Mimics were optimized by Geomagics software,and then three internal fixation models were built and assembled with the femur model according to the parameters of the clinical application of the cannulated compression screw,dynamic hip screw,and femoral neck system by using Pro/E software.Finally,the three internal fixation models were imported into Ansys software for loading and calculation to analyze the stress distribution and displacement of the femur and the internal fixation under different working conditions of single-leg standing loads and sideways fall loads,as well as the stress characteristics of the calcar femorale and Ward's triangle. RESULTS AND CONCLUSION:(1)Under the single-leg standing load and the sideways fall load,the proximal femoral stress of the three internal fixation models was mainly distributed above the fracture end of the femoral neck.The peak stress of the proximal femoral end,fracture end,Ward triangle,and calcar femorale of the three internal fixation models were the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(2)Under the single-leg standing load and the sideways fall load,the peak displacement of the proximal femur of the three internal fixation models was all located at the top of the femoral head,and the peak displacement was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(3)The peak displacement of the three internal fixation models was all located at the top of the internal fixation device under the single-leg standing and sideways fall loading conditions,and the peak displacement values were the smallest in the femoral neck system internal fixation model and the largest in the cannulated compression screw internal fixation model.(4)The internal fixation stress of the three internal fixation models was mainly distributed in the area near the fracture end of the internal fixation device under the single-leg standing and sideways fall loads,and the peak value of internal fixation stress was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(5)These results suggest that the mechanical stability of the femoral neck system is the best,but there may be a risk of stress shielding of the fracture end and calcar femorale.The stress of the internal fixation device of the femoral neck system is more dispersed,and the risk of internal fixation break is lower.

OBJECTIVE:Anterior cervical decompression and fusion is a classic surgical method for the treatment of degenerative cervical spondylosis.The use of nail plates increases the fusion rate and stability and indirectly leads to adjacent vertebral degeneration and postoperative dysphagia.In this paper,the clinical results and complications of ROI-CTM self-locking system and traditional cage combined with screw-plate internal fixation in the treatment of degenerative cervical spondylosis were compared by meta-analysis to provide evidence-based support for the selection of internal fixation methods in anterior cervical decompression and fusion. METHODS:CNKI,WanFang,VIP,PubMed,Cochrane Library,Web of Science,and Embase databases were searched for Chinese and English literature on the application of ROI-CTM self-locking system and fusion cage combined with screw plate internal fixation in the treatment of degenerative cervical spondylosis.The retrieval time range was from inception to July 2023.Two researchers selected the literature strictly according to the inclusion and exclusion criteria.The Cochrane bias risk tool was used to evaluate the quality of randomized controlled trials.Newcastle-Ottawa Scale was used to assess the quality of cohort studies.Meta-analysis was performed using RevMan 5.4 software.Outcome indicators included operation time,intraoperative blood loss,Japanese Orthopaedic Association score,Neck Disability Index,C2-C7 Cobb angle,fusion rate,incidence of adjacent vertebral degeneration,cage subsidence rate,and incidence of dysphagia. RESULTS:Thirteen articles were included,including eleven retrospective cohort studies and two randomized controlled trials,with 1 136 patients,569 in the ROI-C group,and 567 in the cage combined with the nail plate group.Meta-analysis results showed that the operation time(MD=-15.52,95%CI:-18.62 to-12.42,P<0.000 01)and intraoperative blood loss(MD=-24.53,95%CI:-32.46 to-16.61,P<0.000 01)in the ROI-C group and the fusion device combined with nail plate group.Postoperative adjacent segment degeneration rate(RR=0.40,95%CI:0.27-0.60,P<0.000 01)and postoperative total dysphagia rate(RR=0.18,95%CI:0.13-0.26),P<0.000 01)were statistically different.The two groups had no significant difference in Japanese Orthopaedic Association score,Neck Disability Index,C2-C7 Cobb angle,fusion rate,or cage subsidence rate(P≥0.05). CONCLUSION:Applying an ROI-CTM self-locking system and traditional cage combined with plate internal fixation in anterior cervical decompression and fusion can achieve satisfactory clinical results in treating degenerative cervical spondylosis.The operation of the ROI-CTM self-locking system is more straightforward.Compared with a cage combined with plate internal fixation,the ROI-CTM self-locking system can significantly reduce the operation time and intraoperative blood loss and has obvious advantages in reducing the incidence of postoperative dysphagia and adjacent segment degeneration.The ROI-CTM self-locking system is recommended for patients with skip cervical spondylosis and adjacent vertebral disease.However,given its possible high settlement rate,using a fusion cage combined with screw-plate internal fixation is still recommended for patients with degenerative cervical spondylosis with multiple segments and high-risk factors of fusion cage settlement,such as osteoporosis and vertebral endplate damage.

BACKGROUND:Small diameter artificial vessels are urgently needed to treat coronary artery and peripheral artery diseases in clinical practice.At present,vascular tissue engineering has become the main method for preparing small diameter artificial vessels.Selecting suitable biomaterials and cell sources is the key factor for successful construction of small diameter tissue engineered vessels. OBJECTIVE:To observe the effect of four kinds of electrospinning membrane materials on proliferation,adhesion and differentiation of bone marrow mesenchymal stem cells into vascular smooth muscle cells. METHODS:Bone marrow mesenchymal stem cells were isolated and extracted from SD rats.The bone marrow mesenchymal stem cells were inoculated separately on polycaprolactone(PCL),polycaprolactone-hyaluronic acid(PCL-HA),polycaprolactone-silk-filament proteins(PCL-SF),and polycaprolactone-gelatin(PCL-GEL)electrospinning membrane materials.After 1,3,and 7 days of culture,the cell arrangement on the material was observed under scanning electron microscope.The proliferation and adhesion of the material were observed by phalloidin staining.The mRNA expressions of CD90,Meflin,and transforming growth factor β were detected by qRT-PCR.After 7 days of induced differentiation into vascular smooth muscle cells,the mRNA expression ofɑ-smooth muscle actin on the material was detected by qRT-PCR. RESULTS AND CONCLUSION:(1)Bone marrow mesenchymal stem cells were arranged along the fibers of the four kinds of electrospinning membranes under scanning electron microscopy.(2)Phalloidin staining showed the regular distribution of bone marrow mesenchymal stem cells on the four kinds of electrospinning membranes and parallel distribution along the fiber direction.Moreover,PCL-HA,PCL-SF,and PCL-GEL electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells than PCL electrospinning membranes.Compared with PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells.(3)qRT-PCR showed that the four kinds of electrospun membrane materials could maintain the mRNA expression of CD90 and Meflin in bone marrow mesenchymal stem cells,but there was no significant difference between groups(P>0.05).The mRNA expression of transforming growth factor β in PCL-HA,PCL-SF,and PCL-GEL groups was higher than that in PCL group on days 1 and 7(P<0.05),and the mRNA expression of transforming growth factor β in PCL-SF group was higher than that in the other three groups on days 3 and 7(P<0.05).The mRNA expression of transforming growth factor β in PCL-HA group was higher than that in PCL-GEL group on day 7(P<0.05).(4)qRT-PCR showed that the mRNA expression of ɑ-smooth muscle actin in PCL-SF group was higher than that in the other three groups(P<0.05),and that in PCL-HA group was higher than that in PCL group(P<0.05).(5)The results indicate that compared with PCL,PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes combined with bone marrow mesenchymal stem cells are more suitable for the preparation of small diameter tissue engineered vessels.

BACKGROUND:Crosslinked sodium hyaluronate gel has good mechanical property,biocompatibility,and biodegradability,and can be used as an isolated protective material in tumor radiation therapy to protect endangered organs from damage caused by excess radiation dose. OBJECTIVE:To investigate the safety and efficacy of crosslinked sodium hyaluronate gel in reducing the dose of radiation to dangerous organs during brachytherapy. METHODS:A total of 16 specific pathogen-free Kunming mice of the same age and similar body weight were selected as experimental subjects and divided into experimental group and control group by the random number table method,with 8 mice in each group.125I seeds were implanted subcutaneously in the back of mice in the experimental group,and then crosslinked sodium hyaluronate gel was injected around the radioactive particles.Only 125I seeds were implanted subcutaneously in the back of mice in the control group.After injection,the distance between the radioactive particles and the epidermis was measured by spiral CT scan,and the surface radiation dose was measured by radiation dosimeter.Within 10 weeks after injection,the growth state,survival rate,skin radiation damage,and gel retention of mice were observed. RESULTS AND CONCLUSION:(1)Spiral CT scan showed that the implanted gel was relatively concentrated and created an effective distance between the radioactive seeds and the epidermis.The body surface radiation dose of the experimental group was significantly lower than that of the control group(P<0.01).(2)During the experimental observation period,mice in both groups survived;mice in the control group showed obvious irritability and other unstable behavior in the late experimental period,and some mice in the experimental group showed similar behavior.The daily food intake of mice in the two groups had no significant change,and the body mass showed the same increasing trend.After implantation of radioactive seeds,the two groups of mice showed different degrees of radioactive skin injury.From day 23 after injection to the end of the experiment,the skin radiation injury score of the experimental group was lower than that of the control group(P<0.01).At week 10 after implantation,6 mice in the experimental group had no obvious gel residue under their skin,and 2 mice had a very small amount of scattered gel-like samples under their skin.(3)Therefore,the crosslinked sodium hyaluronate injection technique can increase the space between the radioactive target area of 125I seeds and the organ at risk outside the target through physical space occupying,which can effectively reduce the dose of the organ at risk,and play a role in the isolation and protection of the organ at risk.