BACKGROUND:The capability of repairing articular cartilage damage is very limited,and tissue engineering technology provides new therapeutic options for repairing damaged cartilage,in which the interaction and induction between chondrocytes,bone marrow mesenchymal stem cells,and synovial mesenchymal stem cells is the basis of autologous healing of cartilage damage. OBJECTIVE:To construct the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system to simulate the in vitro microenvironment of chondrocytes,and to explore the optimal cell inoculation ratio,meanwhile to observe the effects of icariin-containing serum on the proliferation of chondrocytes and the chondrogenic differentiation of stem cells in the system. METHODS:Rat knee chondrocytes,bone marrow mesenchymal stem cells and synovial mesenchymal stem cells were extracted,cultured and identified,and a chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell non-contact co-culture system was constructed according to different cell inoculation ratios.After 72 hours of co-culturing,the chondrocyte proliferative activity and phenotypic ability were observed,and the co-culture system with the best overall effect was selected.New Zealand white rabbits were gavaged with icariin solution(0.25 mg/mL)to prepare icariin-containing serum,and cultured in conventional complete medium(high sugar DMEM culture medium containing 10%fetal bovine serum and 1%double antibody by volume)as the control group,while the experimental group was intervened by adding 10%icariin-containing serum by volume on the basis of above.The proliferative activity of chondrocytes and the expression of collagen type II were tested for the two groups after 24 and 48 hours.The differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells into chondrocytes in the co-culture system was tested by immunofluorescence staining after 14 days. RESULTS AND CONCLUSION:(1)The three kinds of cells grew normally adherently to the wall in different ratios of co-culture,where chondrocytes showed the best proliferative activity and phenotypic ability in the co-culture system when chondrocytes:bone marrow mesenchymal stem cells:synovial mesenchymal stem cells=2:1:1.(2)Compared with the control group,the proliferative activity and type II collagen expression of chondrocytes in the experimental group were significantly increased after 24 hours(P<0.01),and the two groups still had difference after 48 hours(P<0.05).The two groups showed obvious chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells after 14 days(P<0.01),and some of the cells appeared round or oval,and the cytoplasmic type II collagen immunofluorescence staining was positive.The fluorescence intensity of the experimental group was significantly higher than that of the control group(P<0.01).(3)The results showed that the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system could be successfully established by the non-contact co-culture method,and the best chondrocyte proliferative activity and phenotypic ability could be obtained when the cell ratio was 2:1:1.Icariin-containing serum had the promoting effect on chondrocyte proliferation,and chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells in the system.

BACKGROUND:The formation of postoperative abdominal adhesions is a complicated process,and the prevention of postoperative adhesions is an urgent problem in clinic. OBJECTIVE:To analyze the mechanism of adhesion at cellular and molecular levels,and to provide theoretical basis for the prevention and treatment of adhesion by mesenchymal stem cell exosomes. METHODS:"Abdominal adhesion,pelvic adhesion,postoperative adhesion,epithelial mesenchymal transformation,mesenchymal stem cells,stem cell exosomes,mesenchymal stem cell exosomes"were selected as Chinese and English search terms.We searched PubMed,CNKI,and Chinese biomedical literature and screened relevant articles on postoperative abdominal adhesion and mesenchymal stem cell exosomal intervention published from inception to August 2023.After systematic analysis,54 articles were finally included for the review. RESULTS AND CONCLUSION:(1)Any pathological factors such as peritoneal inflammation,mechanical injury,tissue ischemia,and foreign body implantation cause peritoneal surface injury,resulting in postoperative abdominal adhesion.The formation process of adhesion includes the interaction of peritoneal mesothelial cell repair,inflammatory response,fibrinolytic system,coagulation pathway and other processes,involving a variety of cytokines and signaling pathways.Wnt/β-catenin pathway can induce fibrosis and angiogenesis,and cooperate with transforming growth factor-β/Smads signaling pathway to stimulate fibroblast proliferation and cause peritoneal fibrosis.Meanwhile,nuclear factor-κB signaling pathway up-regulates the expression of cellular inflammatory factors,promotes fibroblast proliferation,and plays a key role in the process of tissue fibrosis.(2)The paracrine function of stem cells is an important direction of molecular intervention in abdominal adhesions based on regenerative medicine.It can participate in a variety of complex cytokines and signaling pathways involved in abdominal adhesions.(3)Compared with traditional methods for treating abdominal adhesions,mesenchymal stem cell exosome has biological activity and is safe to use.Mesenchymal stem cell exosomes without special culture and expansion have lower immunogenicity,longer stability and other advantages,can guide a normal repair and healing through a variety of ways.(4)Mesenchymal stem cell exosome has been proven to be involved in regulating the above processes of adhesion formation in previous studies,showing potential application prospects in clinical studies.However,further clinical studies are needed to explore appropriate treatment options for mesenchymal stem cell exosomes to address the problem of clinical translation.

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:Recent research indicates that disc degeneration is closely related to abnormal stress load,and mechanotransduction proteins play a key role in it. OBJECTIVE:To investigate the role and mechanism of mechanotransduction proteins in the mechanotransduction process induced by abnormal mechanical stimulation in disc degeneration,and to summarize the current treatment strategies targeting mechanotransduction to delay intervertebral disc degeneration. METHODS:Using"intervertebral disc,nucleus pulposus,annulus fibrosus,cartilaginous endplate,cell,mechanics,signal transduction,protein,biomechanics"as Chinese search terms,and"intervertebral disc,nucleus pulposus,annulus fibrosus,cartilaginous endplate,cell,mechanical stimulation,signal transduction,protein,biomechanics"as English search terms,relevant literature in the PubMed and CNKI databases was searched.A total of 88 articles were ultimately included for review. RESULTS AND CONCLUSION:Disc cells can sense external mechanical stimulation through various mechanotransduction proteins and convert it into biological responses within the cells.These transduction proteins mainly include collagen proteins in the extracellular matrix,cell membrane surface receptors(such as integrins and ion channels),and cytoskeleton structural proteins.Their regulation of mechanotransduction processes primarily involves the activation of multiple pathways,such as the PI3K/AKT signaling pathway,nuclear factor-kB signaling pathway,and Ca2+/Calpain2/Caspase3 pathway.Mechanotransduction proteins play a key role in the mechanotransduction of disc cells.Abnormal expression of these proteins or resulting changes in the extracellular matrix environment can disrupt the mechanical balance of disc cells,leading to disc degeneration.In-depth study of the expression and regulatory mechanisms of mechanotransduction proteins in disc cells,and identification of key pathological links and therapeutic targets,is of significant importance for developing treatment strategies for disc degeneration.Current strategies to delay intervertebral disc degeneration by targeting mechanotransduction mainly include regulation of transduction proteins and improvement of the extracellular matrix.However,research in this area is still in its early stages.As research continues,new breakthroughs are expected in the regulation of disc degeneration by mechanotransduction proteins.

BACKGROUND:Micro-abrasion,at-home whitening combined with infiltration resin have a good effect on dental fluorosis,but the effect of this method on micro-cracks in dental fluorosis is still unclear. OBJECTIVE:To explore the effect of micro-abrasion,at-home whitening combined with infiltration resin on micro-cracked dental fluorosis. METHODS:(1)Clinical research:A total of 23 patients with micro-cracked dental fluorosis,including 255 micro-cracked dental fluorosis,were selected from July 2020 to March 2021 in the Department of Prosthodontics,Stomatology Hospital,Tianjin Medical University.All of them received combined treatment of tooth micro-abrasion,at-home whitening and infiltration resin.The tooth color,tooth sensitivity,and tooth pain threshold were compared before treatment and 1 week and 1 month after treatment.(2)In vitro experiment:60 teeth with fluorosis with at least one crack on the tooth surface were collected and randomly divided into three groups for treatment.The control group was treated without any treatment.The whitening group was treated with micro-abrasion and at-home whitening,and the combined group was treated with micro-abrasion,at-home whitening,and infiltration resin,with 20 teeth in each group.The microhardness of the three groups of teeth samples after treatment was measured. RESULTS AND CONCLUSION:(1)Clinical study:6 months after treatment,among 255 teeth with micro-cracked dental fluorosis,whitening treatment for 207 teeth was significantly effective and whitening treatment for 48 teeth was effective,and the overall treatment efficiency was 100%.With the extension of treatment time,the proportion of moderate and severe dental sensitivity showed a decreasing trend.At 6 months after treatment,255 teeth with dental fluorosis had no severe sensitivity,15 with moderate sensitivity,125 with mild sensitivity,and 115 with no sensitivity,and the difference was significant compared with the sensitivity before treatment(P<0.05).There was no significant difference in the threshold of tooth pain before treatment and 1 week and 6 months after treatment(P>0.05).(2)In vitro experiment:The tooth microhardness of the whitening group was lower than that of the control group and the combined group(P<0.05),but there was no significant difference between the control group and the combined group(P>0.05).(3)The results show that the methods of micro-abrasion,at-home whitening combined with infiltration resin have good clinical efficacy in the treatment of micro-cracked dental fluorosis.

Objective To investigate the features of non-motor symptoms and transcranial substantia nigra ultrasound in essential tremor （ET）. Methods General data were collected from 50 patients with ET and 50 healthy controls，and non-motor symptom scales and transcranial nigra sonography （TCS） were used for assessment. The t-test，the non-parametric test，and the chi-square test were used for comparison of general data，scale assessment results，and TCS findings between the two groups. Results There were significant differences between the ET group and the healthy control group in the total scores of NMSS，MoCA，HAMA，HAMD，PSQI，ESS，and FSS and the incidence rates of cognitive impairment，moderate or severe anxiety，poor sleep，and daytime sleepiness，while there were no significant differences in the incidence rates of moderate or severe depression and fatigue between the two groups. There were no significant differences between the two groups in terms of “hyperechoic area of the left side” “hyperechoic area of the right side” “hyperechoic area of both sides” “S/M value” “the number of cases with a hyperechoic area of >0.2 cm2 for at least one side” “the number of cases with an S/M ratio of >7%” and “the number of cases with positive TCS results”. Conclusion Compared with healthy controls，ET patients are more susceptible to cognitive impairment，anxiety，depression，poor sleep quality，daytime sleepiness，and fatigue，and the non-motor symptoms of ET should be taken seriously in clinical practice. TCS examination has a relatively low diagnostic value in ET patients and healthy individuals.

Objective:To investigate the effect of inhibitory activity of high mobility group protein B1 (HMGB1), signal transduction and activator of transcription 3 (STAT3) on myocardial ischemia-reperfusion injury in rats.Methods:In vivo and in vitro models of MIRI were established. SD rats were randomly divided into a sham group, a model group, a glycyrrhizic acid group, and a NSC74859 group, with 6 rats in each group. Rats in the sham group were not ligation, and rats in the sham group and model group were not given medication. The rats in the glycyrrhizic acid group and the NSC74859 group were injected with HMGB1 antagonist glycyrrhizic acid or STAT3 inhibitor NSC74859 5 mg/kg in the tail vein at 12 h 30 min before ischemia/reperfusion and 30 min after ischemia, respectively. Left ventricular shortening fraction (FS) and left ventricular ejection fraction (EF) were evaluated by echocardiography, and apoptosis of cardiomyocytes was evaluated by hematoxylin-eosin (HE) and TUNEL staining. The expression levels of HMGB1, STAT3, and phosphorylated STAT3 (p-STAT3) were detected by real-time fluorescence quantitative PCR and Western Blot. The viability of H9C2 cells was determined by the MTS assay, intracellular ATP content was determined, and the mitochondrial membrane potential of H9C2 cells was measured by flow cytometry to evaluate the survival of cardiomyocytes. The action mode of HMGB1/STAT3 was studied by the immunoprecipitation method. The expression and migration of HMGB1/STAT3 in the nucleus and cytoplasm were detected by immunostaining. Results:After inhibiting the expression of HMGB1 or STAT3, EF and FS were increased, and immune infiltration and apoptosis of cardiomyocytes were decreased. Inhibition of HMGB1 expression could decrease the expression of STAT3, but inhibition of STAT3 expression didn’t affect the expression of HMGB1. Hypoxia could lead to increased expression of HMGB1 and p-STAT3, and decreased expression of STAT3. After 8 hours of hypoxia, the expression level of STAT3 suddenly increased. After reoxygenation, the expression of HMGB1 and STAT3 decreased, and the expression of p-STAT3 increased, but p-STAT3 (Ser 727) didn’t participate in this process. After ischemia-reperfusion injury, HMGB1 and STAT3 binded firmly in cardiomyocytes, but inhibition of STAT3 or HMGB1 weakened this binding. Inhibition of HMGB1 or STAT3 expression could reduce myocardial ischemia-reperfusion injury. The expression of HMGB1 in reoxygenated cardiomyocytes increased after hypoxia, and HMGB1 migrated from the nucleus to the cytoplasm.Conclusions:Inhibiting the activity of the HMGB1/STAT3 axis effectively reduces MIRI in rats.

Objebtive:To investigate the effect of baicalin on cell apoptosis and related cytokines in diabetic retinopathy.Methods:Sixty SD rats were randomly divided into a control group, a model group, and a baicalin group, with 20 rats in each group. The diabetic retinopathy model was established after fed by a high-sugar, high-fat diet for 4 weeks by intraperitoneal injection of 50 mg/kg streptozotocin. Rats in the control group weren’t done any treatment, only with normal diet. Rats in the model group was not given drug treatment,While rats in the baicalin group 50 mg/kg intrabitoneal injection of baicalin. The results of HE staining, TUNEL cell apoptosis, retinal cell apoptosis index, and the expression of cleaved-cysteinyl aspartate-specific proteinase-3 (cleaved-Caspase-3), B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X (Bax) protein in the retina of the three groups were observed.Results:The internal limiting membrane of the retina in the control group was smooth. Compared with the control group, the loss of ganglion cells in the model group was significantly increased, the retinal thickness was thinner, and the thickness of the inner nuclear layer and the outer nuclear layer was thinner. Compared with the model group, the number of ganglion cells in the baicalin group was significantly increased, the retinal thickness was thickened, and the thickness of the inner nuclear layer and the outer nuclear layer was thickened. Apoptotic cells were brown after TUNEL labeling. A large number of apoptotic cells were observed in the model group, and the cell arrangement was disordered. Only a few apoptotic cells were observed in the control group, and the cells were arranged neatly. Compared with the model group, the apoptotic cells in the baicalin group were significantly reduced ( P < 0.05), and the cells were arranged neatly. The apoptosis index of retinal cells in the sham group was lower than that in the model group and the baicalin group, and the baicalin group was lower than that in the model group ( P < 0.05). Compared with the control group, the expression of cleaved-Caspase-3 and Bax protein in the retina of the model group was significantly increased, and Bcl-2 was significantly decreased; the difference was statistically significant ( P < 0.05). Compared with the model group, the expression of cleaved-Caspase-3 and Bax protein in the baicalin group was down-regulated, and Bcl-2 was significantly up-regulated; the difference was statistically significant ( P < 0.05). Conclusions:Baicalin can improve diabetic retinopathy by inhibiting the apoptosis rate of DR rats, down-regulating the expression of cleaved-Caspase-3 and Bax, and up-regulating the expression of Bcl-2.

Traditional drugs for the treatment of abdominal tumors often do not have the ability to target tumors and destroy normal cells while killing tumor cells. Therefore, new therapies are urgently needed to accurately target and kill tumor cells. As a drug carrier, extracellular vesicles have the advantages of naturalness, biotaxis, and low side effects, so they have attracted much attention in the research on the treatment of abdominal tumors. In this paper, the research progress in mechanism of action of extracellular vesicle drug delivery system in the treatment of abdominal tumors such as gastric, liver, pancreatic, bile duct, colorectal, and ovarian cancers with an extracellular vesicle drug delivery system was reviewed, including inhibiting the growth of abdominal tumor cells, reversing the drug resistance of the tumor stem cells, inhibiting the exocytosis of chemotherapeutic drugs from the tumor cells, and remodeling the tumor immune microenvironment.

Objective:To investigate the effects of extracts of Rhizoma Sparganii and Rhizoma Curcumae on cartilage damage in osteoarthritis rats and NADPH oxidase 2 (NOX2)/reactive oxygen species (ROS)/nuclear factor-κB (NF-κB) signaling pathways. Methods:Rats (50 cases) were divided into the sham group, and model group, as well as the low, medium, and high dose groups of extracts of Rhizoma Sparganii and Rhizoma Curcumae, with 10 rats in each group. Except for sham group, the rat model of cartilage damage in knee osteoarthritis was established. On the second day after modeling, the rats in the low, medium, and high dose groups received intragastric extracts perfusion of Rhizoma Sparganii and Rhizoma Curcumae at the doses of 5, 10, and 20 g/kg respectively. The rats in the sham and model groups received intragastric equivalent 0.9% sodium chloride solution perfusion, once daily, for 20 days by continuous administration. The knee joint behavior, bone metabolism indicators, serum superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH) levels, inflammatory factors, NOX2, and NF-κB levels of each group were observed. Results:Compared with the model group, the behavioral abnormality scores, cartilage oligomeric matrix protein (COMP), MDA, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), NOX2, and NF-κB levels in the low, medium, and high dose groups were all gradually decreased (all P < 0.05), while proteoglycan, SOD, GSH, and interleukin-10 (IL-10) levels in the low, medium, and high dose groups were all gradually increased (all P < 0.05), and it was dose-dependent. Conclusions:Rhizoma Sparganii and Rhizoma Curcumae extracts can effectively improve cartilage damage in osteoarthritis rats, and it may be related to the inhibition of the NOX2/ROS/NF-κB signaling pathway.