BACKGROUND:Previous studies have demonstrated that the cannabinoid type Ⅰ receptor can enhance the proliferation and neural differentiation of neural stem cells and mesenchymal stem cells.Moreover,cannabinoid type Ⅰ also governs the proliferation and mineralization capacity of human apical papilla stem cells.However,there are relatively few investigations concerning the impact of cannabinoid type Ⅰ overexpression on the neural differentiation of human apical papilla stem cells.OBJECTIVE:To investigate the effect of cannabinoid type Ⅰ on neural differentiation of human apical papilla stem cells in vitro.METHODS:Healthy third molars with immature root tips that need to be removed for orthodontic treatment were collected,and human apical papilla stem cells were isolated and cultured by tissue block method combined with enzyme digestion method.Cannabinoid type Ⅰ gene was introduced into human apical papilla stem cells by lentivirus-mediated transfection technique.A blank control group,a negative control group,and cannabinoid type Ⅰ overexpression group were set up.The transfection effect of overexpression of cannabinoid type Ⅰ lentivirus on human apical papilla stem cells was verified by Western Blot.The control group,negative control group,cannabinoid type Ⅰ overexpression group and cannabinoid type Ⅰ overexpression+AM251(cannabinoid type Ⅰ receptor antagonist)group were set up.Cell proliferation was detected by CCK-8 assay at 1,5,and 10 days after neural induction.On day 10 of neural induction,the expression levels of TH,NeuroD-1,and NCAM1 genes were detected by qRT-PCR,and the protein expression levels of Nestin and TUBB3 were detected by immunofluorescence.RESULTS AND CONCLUSION:(1)Compared with the blank control group and the negative control group,the expression of cannabinoid receptor Ⅰ protein in the cannabinoid receptor Ⅰ overexpression group was significantly increased,and the difference was significant(P＜0.05).(2)Compared with the blank control group and the negative control group,the proliferation ability of human apical papilla stem cells in the cannabinoid type Ⅰ overexpression group was the strongest at 5 and 10 days after neural induction(P＜0.05).(3)Compared with the blank control group and the negative control group,the mRNA expression of NeuroD-1,NCAM1,and TH in the stem cells of the human apical papilla in the cannabinoid type Ⅰ overexpression group was significantly increased,and the fluorescence intensity of Nestin and TUBB3 was significantly enhanced(P＜0.05).(4)Compared with the cannabinoid type Ⅰ overexpression group,the proliferation ability,mRNA expression level of NeuroD-1,NCAM1,and TH,as well as the fluorescence intensity of Nestin and TUBB3,were significantly decreased in the cannabinoid type Ⅰ overexpression+AM251 group(P＜0.05).These findings conclude that overexpression of cannabinoid type Ⅰ promoted the proliferation and neural differentiation of human apical dentin papilla stem cells.

BACKGROUND:Lysosomal storage diseases,as a group of rare genetic metabolic disorders,exhibit complex pathogenesis often leading to dysfunction of cells,tissues,and organs.Current therapeutic approaches have certain limitations.Stem cell transplantation,as an emerging treatment method,offers new options for patients with lysosomal storage diseases.OBJECTIVE:To review the mechanisms of action of stem cells in regulating lysosomes for the treatment of lysosomal storage diseases and explore the feasibility of traditional Chinese medicine in treating such diseases,providing new insights for the treatment of lysosomal storage diseases with stem cells.METHODS:Relevant literature from 2010 to 2024 was searched in CNKI and PubMed databases using keywords"stem cells,lysosomal storage disease,lysosome"in English and Chinese.Ultimately,78 articles were included for review and analysis.RESULTS AND CONCLUSION:(1)Stem cells treat lysosomal storage diseases by regulating lysosomes primarily through three aspects:regulating stem cell differentiation and replacement,improving intercellular communication and the microenvironment,and enhancing lysosomal enzyme expression through gene editing.(2)Stem cells have achieved significant effects in the treatment of some lysosomal storage diseases,such as Niemann-Pick disease,mucopolysaccharidoses,Gaucher disease,and metachromatic leukodystrophy.(3)The procedure for stem cell transplantation needs further optimization.Adverse reactions post-transplantation urgently need to be addressed,and the efficiency and safety of gene-modified stem cells also need to be further improved.In the future,more research on the treatment of lysosomal storage diseases with traditional Chinese medicine is required to reveal the relevant mechanisms for the treatment of lysosomal storage diseases with traditional Chinese medicine.

BACKGROUND:Exosomes derived from mesenchymal stem cells play pivotal roles in cell communication and epigenetic regulation due to their low immunogenicity and targeted delivery effects,and have been clinically applied in the treatment of various diseases.OBJECTIVE:To review the isolation,purification,identification methods,and application progress of mesenchymal stem cell-derived exosomes,and to facilitate the development of large-scale preparation techniques and clinical translation of mesenchymal stem cell-derived exosomes.METHODS:The Chinese search terms"exosome,mesenchymal stem cells,isolation,purification,characterization,clinical application"and the English search terms"exosome,extracellular vesicles,mesenchymal stem cells,isolation,characterization,application"were used to search the literature published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating and purifying exosomes,comparing the characteristics of ultracentrifugation,ultrafiltration,size-exclusion chromatography,polymer precipitation,immunoaffinity,microfluidic methods,and other novel approaches based on their underlying principles.(2)Methods for identifying exosomes can be categorized into physical and biochemical analyses,characterizing exosomes based on their shape,size,and characteristic proteins.(3)Mesenchymal stem cell-derived exosomes have broad applications in multiple fields such as medical aesthetics,wound repair,and cancer treatment,due to their immune-regulatory properties and ability to cross biological barriers.(4)The clinical translation of exosomes faces challenges due to their complex structure,lack of universal isolation techniques,and poor stability,making it difficult to achieve in a short period of time.

BACKGROUND:One of the advantages of clear aligner treatment is molar distalization.However,tooth tilting movement and loss of anterior anchorage may occur during treatment.There are few studies on whether these problems can be improved by selecting clear aligners with different thicknesses and edges to improve the clinical treatment effect.OBJECTIVE:To analyze the control ability of clear aligners with different thickness and edges on the central incisor,lateral incisor,and second molar when pushing the maxillary second molar distally by three-dimensional finite element analysis.METHODS:Three-dimensional finite element analysis models of bilateral maxillary second molar distalization with clear aligner,maxillary dentition,periodontal ligament,and alveolar bone with different thicknesses and margins were established by Mimics,Geomagic Wrap,3-matic and SolidWorks software,respectively.There were 16 combinations of four thicknesses(0.4,0.5,0.625,and 0.75 mm)and four margins(scallop,straight,straight extension 2 mm and straight extension 4 mm).The data were imported into Ansys Workbench software for design and solution.The mean value,peak value and distribution of the periodontal ligament equivalent stress of the second molar,the equivalent stress and the maximum initial displacement of the second molar,and the control ability of each appliance on the second molar,central incisor,and lateral incisor were analyzed.RESULTS AND CONCLUSION:(1)The mean equivalent stress of periodontal ligament of the second molar,the equivalent stress of the second molar and the maximum initial displacement of the second molar increased with the extension of the appliance edge and the increase of the thickness of the appliance in the 16 groups of models.(2)When the thickness of appliances was the same,the maximum equivalent stress of the second molar in the linear appliance group was the highest,and the maximum equivalent stress of the second molar in the linear extended appliance group was greater than that in the scallop appliance group.When the edge of the appliance was the same,the periodontal ligament equivalent stress peak of the second molar increased with the increase of the thickness of the appliance.The equivalent stress distribution in the periodontal ligament of the second molar in the linear extendable appliance group was more uniform than that in the scallop appliance group and the linear appliance group.(3)When the thickness of the appliance was the same,the scallop-shaped appliance had the worst control on the second molar.When the edge of the appliance was the same,with the increase of the thickness of the appliance,the control of the second molar by the linear extender appliance was gradually stronger than that by the linear appliance.The control of the central incisor was stronger and more stable with the linear extended 2 mm appliance,while the control of the lateral incisor was stronger and more stable with the linear appliance.(4)The results showed that when using clear aligners to push molars distally,extending the edge of the appliance could improve the control of the molars and reduce the tilting movement of the teeth.The design of a straight extension margin of 2 mm for the central incisor and a straight edge for the lateral incisor can enhance the control of the anchorage incisor and reduce the labial inclination of the anterior teeth.

BACKGROUND:Mesenchymal stem cells show extremely therapeutic potential for radiation-induced lung injury through delivering exosomes.Age is a primary factor affecting the function and biological efficacy of mesenchymal stem cells.OBJECTIVE:To investigate the protective effects of exosomes derived from bone marrow mesenchymal stem cells of different mouse ages on radiation-induced lung injury in mice.METHODS:Bone marrow mesenchymal stem cells of young mice and old mice were obtained by whole bone marrow adherent culture.The exosomes were isolated from the supernatant of passage 3 bone marrow mesenchymal stem cells.Ten 2-month-old C57BL/6J mice were randomly selected as the control group after anesthesia and not irradiated.The remaining 30 2-month-old C57BL/6J mice were used to establish a mouse radiation-induced lung injury model and were randomly divided into three groups.Exosomes derived from bone marrow mesenchymal stem cells of young mice,exosomes derived from bone marrow mesenchymal stem cells of old mice,and PBS were injected through the tail vein,respectively.The survival rate of mice was monitored.The lung function,lung inflammation and fibrosis were assessed at 1 and 12 weeks after irradiation.RESULTS AND CONCLUSION:(1)The concentrations of particles and proteins in exosomes derived from bone marrow mesenchymal stem cells of young mice were higher than those in exosomes derived from bone marrow mesenchymal stem cells of old mice.(2)Compared with the control group,the survival rate of mice in the PBS group was low,and lung inflammation was obvious at week 1 after irradiation,and the levels and mRNA expressions of interleukin-1β,interleukin-6,and tumor necrosis factor-α were increased.Collagen deposition in lung tissues was observed at week 12 after irradiation,and the mRNA level of E-cadherin was decreased,while the mRNA levels of α-smooth muscle actin,transforming growth factor-β1,and β-catenin were increased.(3)Compared with the PBS group,the survival rate of mice in the exosome group was significantly improved,and the level of proinflammatory factors and their mRNA expression were reduced at week 1 after irradiation,the mRNA level of E-cadherin was increased,and the mRNA levels of α-smooth muscle actin,transforming growth factor β1 and β-catenin were reduced at week 12 after irradiation.(4)Among all the above indicators,the therapeutic effect of exosomes derived from bone marrow mesenchymal stem cells of young mice was better than that of exosomes derived from bone marrow mesenchymal stem cells of old mice.(5)The results showed that exosomes derived from bone marrow mesenchymal stem cells of young mice contained more particles and proteins,and the effect of alleviating early inflammation and late fibrosis of radiation-induced lung injury in mice was better than that of exosomes derived from bone marrow mesenchymal stem cells of old mice.

BACKGROUND:Mineralized collagen is the fundamental unit of bone structure and function and a major component of the extracellular matrix.Biomimetic methods have been developed to fabricate mineralized collagen with a natural bone nanostructure.Currently,mineralized collagen has been approved by regulatory authorities and applied clinically,playing a positive role in bone defect repair.OBJECTIVE:To present the integration strategies of bioactive factors with mineralized collagen,summarize schemes to enhance the osteogenic potential of mineralized collagen,emphasize the multifunctional coordination applications of mineralized collagen,and finally discuss current research focuses and future trends.METHODS:The authors searched for relevant literature in databases such as PubMed,Web of Science,Medline,WanFang,and CNKI,from 2009 to 2023,using keywords"mineralized collagen,biomimetic,functionalization,bioactive factors,osteogenesis,multi-functional coordination,bone tissue repair"in English and"mineralized collagen,biomimetic,functionalization"in Chinese.Out of 375 initially identified articles,57 were included for review after screening.RESULTS AND CONCLUSION:(1)Mineralized collagen,with its porous structure and large surface area,containing nano-hydroxyapatite,makes it an effective carrier for cells,various growth factors,and drugs.(2)Single or multiple bioactive factors can be efficiently and orderly released through different loading methods or combinations,achieving the multifunctionalization of mineralized collagen.The impact of physicochemical conditions on the bioactivity of factors and their effects on the degradability,hydroxylapatite crystal morphology,nanostructure,and content of mineralized collagen should be considered.Moreover,calcium ions in mineralized collagen can be substituted with various inorganic non-metal ions,enhancing its osteogenic,angiogenic,immunomodulatory,and anti-infective properties.(3)Ultimately,during in situ bone regeneration,functionalized mineralized collagen serves as a scaffold material,providing structural support for bone defects,and as a drug delivery system,continuously delivering various bioactive factors locally,playing roles in anti-infection,immunomodulation,promoting angiogenesis and osteogenesis,and repairing various complex bone defects.

BACKGROUND:Choline kinase alpha is a key enzyme in phospholipid metabolism,involved in the synthesis of phosphatidylcholine,and plays an important role in maintaining cell membrane integrity and signal transduction.Research has shown that choline kinase alpha is highly expressed in various tumors and is closely related to cell proliferation,metabolic reprogramming,and tumor progression.As a potential therapeutic target,the role of choline kinase alpha in tumor metabolism and mitochondrial function still needs further exploration.OBJECTIVE:To evaluate the effects and the underlying mechanisms of choline kinase alpha on the proliferation and apoptosis of glioma U87MG and U251 cells.METHODS:Short hairpin RNA of choline kinase alpha and its empty vector control were transfected into U87MG and U251 glioma cells.Mitochondrial morphology was observed by transmission electron microscopy.Mitochondrial structure and functional protein levels were assessed by western blot assay.Reactive oxygen species levels in cells were measured using a reactive oxygen species fluorescent probe.Mitochondrial membrane potential was assessed with a JC-1 assay.Intracellular adenosine triphosphate levels were measured by chemiluminescence.Cell proliferation was evaluated using a CCK-8 assay.Apoptosis levels were analyzed by flow cytometry.The mitochondrial fission inhibitor Mdivi-1 was used to protect the mitochondrial function of the choline kinase α-silenced lentiviral cells.Finally,U87MG cells were subcutaneously injected to construct a subcutaneous tumor model in nude mice.The tumor growth in nude mice was observed before and after choline kinase alpha silencing and after the use of the mitochondrial fission inhibitor Mdivi-1.RESULTS AND CONCLUSION:(1)Compared with the empty control group,the mitochondria of U87MG and U251 cells in the choline kinase alpha silencing lentivirus group exhibited significant structural abnormalities in mitochondria,such as vacuolization and cristae disruption.The expressions of mitochondrial structure and function-related proteins TOM20,ACO2,and ATP5A were significantly decreased(P＜0.01,P＜0.001),the expression of SOD2 was significantly increased(P＜0.01,P＜0.000 1),the fluorescence intensity of reactive oxygen species was significantly increased(P＜0.01),the mitochondrial membrane potential and adenosine triphosphate level were significantly decreased(P＜0.01,P＜0.001),the cell proliferation ability was reduced(P＜0.01),and the apoptosis level was increased(P＜0.001).(2)Following Mdivi-1 treatment,the fluorescence intensity of reactive oxygen species in U87MG and U251 cells decreased(P＜0.05,P＜0.01),mitochondrial membrane potential and adenosine triphosphate levels were significantly restored(P＜0.05,P＜0.01,P＜0.001),cell proliferation ability was improved(P＜0.05,P＜0.01),and apoptosis level was decreased(P＜0.05).(3)In addition,the in vitro subcutaneous tumor formation experiment of nude mice showed that compared with the empty control group,the mass and growth rate of subcutaneous tumors formed by U87MG cells in the choline kinase alpha silencing lentivirus group were significantly reduced(P＜0.000 1).After Mdivi-1 treatment,the mass and growth rate of tumors were significantly increased(P＜0.000 1).(4)The results show that choline kinase alpha silencing affects the proliferation and apoptosis of glioma cells by inducing mitochondrial dysfunction.

BACKGROUND:Exosomes,as a type of extracellular vesicle,have become a key medium for cell-to-cell communication due to their nanoscale size and enrichment of various bioactive substances.The study of exosome secretion regulation not only has important scientific value,but also has broad application prospects in clinical practice,and is of great significance for promoting medical progress and improving human health.OBJECTIVE:To review the biological characteristics,biological functions,biogenesis process and biochemical regulation mechanism of exosomes,and to explore the application prospects of exosomes in disease diagnosis,treatment and vaccine development,so as to provide theoretical basis and reference for basic research and clinical transformation of exosomes.METHODS:The first author searched PubMed and CNKI databases in October 2024 for relevant literature published from January 2010 to October 2024.Key words were"exosomes,biological functions,biogenesis,secretion or release,regulatory mechanisms,application prospects"in Chinese and English.Finally,92 articles were included for analysis.RESULTS AND CONCLUSION:The secretion level of exosomes can be regulated through physical or biochemical means.Exosomes show broad application prospects in the fields of disease diagnosis,treatment,and vaccine development,and may play a key role in the treatment of cardiovascular and cerebrovascular diseases as well as cancer.This review provides valuable information for the clinical translation and application research of exosomes,helping to promote future progress in exosome research and application.

BACKGROUND:Osteoarthritis is pathologically characterized by progressive degeneration of the articular cartilage and abnormal deformation of the subchondral bone.In recent years,with the deepening of medical research,it has been found that the mitogen-activated protein kinases(MAPK)signaling pathway has a regulatory role in inflammatory cell infiltration,inflammatory factor release,and chondrocyte proliferation,which is particularly important for the treatment of osteoarthritis.OBJECTIVE:To briefly review the main research progress in the mechanism of MAPK signaling pathway regulating osteoarthritis in recent years,aiming to provide new ideas for the treatment of osteoarthritis.METHODS:CNKI,WanFang and PubMed databases were searched for relevant literature using the search terms of"mitogen-activated protein kinases,osteoarthritis,extracellular signal-regulated MAP kinases,p38 mitogen-activated protein kinases,JNK mitogen-activated protein kinase"in Chinese and English.Relevant literature published from January 2019 to November 2024 was searched,and 108 articles were finally included for summary analysis.RESULTS AND CONCLUSION:(1)Various stimuli inside and outside the cells activate the MAPK signaling pathway,regulate gene transcription and protein synthesis,and promote the release of inflammatory factors,such as tumor necrosis factor-α,interleukin-1β,and interleukin-6.The release of these inflammatory factors aggravates the progression of osteoarthritis.(2)The active ingredients of traditional Chinese medicine,mainly saponins and flavonoids,as well as Chinese herbal formulas and preparations with the main effects of activating blood circulation and removing blood stasis,tonifying the liver and kidney,can play a therapeutic role in osteoarthritis by inhibiting the MAPK signaling pathway,regulating the release of matrix metalloproteinases,balancing the homeostatic state of osteogenesis and osteoblastogenesis,attenuating the synovial inflammation,decreasing the release of inflammatory factors and inflammatory vesicles,decreasing cellular pyroptosis,promoting autophagy,and ameliorating oxidative stress.(3)Although traditional Chinese medicine has become popular in the treatment of osteoarthritis by virtue of its own advantages of multi-components,multi-targets,multi-pathways,and low side effects,the use of MAPK signaling pathway to guide the treatment of individual osteoarthritis is the difficulty of the technology,which needs to be continuously researched and explored.(4)Therefore,further development of relevant herbal inhibitors that can modulate the MAPK signaling pathway may be a potential drug strategy for the treatment of osteoarthritis in the future.

BACKGROUND:Promoting skin wound healing is a huge challenge facing global public health.To promote faster and higher-quality wound healing,it is necessary to explore more advantageous dressings to address this problem.OBJECTIVE:To investigate the hemostatic properties of acellular dermal matrix hydrogel and its effect on skin wound healing.METHODS:(1)Acellular dermal matrix hydrogel was prepared,and the differences in microscopic morphology and main components between it and acellular dermal matrix were analyzed.(2)Acellular dermal matrix hydrogel and chitosan hydrogel were used to cover the femoral artery puncture site of rats,and the bleeding quality and coagulation time were recorded.Acellular dermal matrix hydrogel and chitosan hydrogel were mixed with rat anticoagulated blood,and the coagulation index within 30 minutes was detected.(3)A full-thickness skin defect model with a diameter of 12 mm was made on the back of 18 SD rats,and they were randomly divided into 3 groups,with 6 rats in each group:the model group used PBS to clean the wound,and the control group and the experimental group used chitosan hydrogel and acellular dermal matrix hydrogel to cover the wound,respectively.The hydrogel dressing was changed every day,and the treatment was continued for 14 days,and the wound healing was observed.On day 3 after modeling,immunofluorescence staining of inducible nitric oxide synthase(M1 macrophages)and CD206(M2 macrophages)was performed on the wound surface.On day 14 after modeling,hematoxylin-eosin staining,Masson staining,and CD31 immunohistochemical staining were performed on the wound surface.RESULTS AND CONCLUSION:(1)Scanning electron microscopy revealed that the acellular dermal matrix hydrogel had a porous structure,and the Fourier transform infrared spectrum showed that it had the same main components as the acellular dermal matrix.(2)Both acellular dermal matrix hydrogel and chitosan hydrogel had obvious hemostatic ability in vivo.In the in vitro coagulation experiments,the coagulation index of acellular dermal matrix hydrogel was significantly higher than that of chitosan hydrogel.(3)In the rat skin full-thickness defect model,both acellular dermal matrix hydrogel and chitosan hydrogel could improve the wound healing rate.Hematoxylin-eosin and Masson staining results showed that acellular dermal matrix hydrogel could reduce the infiltration of inflammatory cells in the center of the wound.Both acellular dermal matrix hydrogel and chitosan hydrogel could decrease scar width and increase collagen deposition rate.CD31 immunohistochemical staining results showed that both hydrogels could promote angiogenesis in the wound site.Immunofluorescence staining results showed that both hydrogels could reduce the proportion of M1 macrophages and increase the proportion of M2 macrophages,and the effect of acellular dermal matrix hydrogel was stronger than that of chitosan hydrogel.(4)The results show that the acellular dermal matrix hydrogel has good hemostatic properties and the ability to promote wound healing.