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BACKGROUND:At present,a large number of studies have found that Liuwei Dihuang Pill can be used to treat osteoporosis,but there are few related studies on the differentiation and mineralization of osteoblasts induced by wear particles using Liuwei Dihuang Pill. OBJECTIVE:To investigate the positive effect of different concentrations of Liuwei Dihuang Pill-containing serum on titanium particle-induced mouse MC3T3-E1 osteoblast in vitro osteolysis model. METHODS:Drug-containing serum was extracted after oral administration of Liuwei Dihuang Pill.The best concentration of Liuwei Dihuang Pill-containing serum and titanium particles on the viability of MC3T3-E1 cells was screened.MC3T3-E1 cells were divided into three groups.The blank group was given osteoblastic differentiation culture.The model group was given titanium particles(5 μg/mL)ossification culture.The drug-containing serum group was given titanium particles(5 μg/mL)+ Liuwei Dihuang Pill-containing serum(10%,15%and 20%doses).Osteoblast viability was detected by CCK-8 assay.Cell alkaline phosphatase activity was detected by alkaline phosphatase staining.Cell mineralization was detected by silver nitrate(Von Kossa)and alizarin red staining.Expression levels of bone differentiation-related genes Runx-2,Osterix,Ocn,Axin,Alp,and Opn were detected by qRT-PCR.Wnt/β-catenin signaling pathways β-catenin,p-GSK-3β,GSK-3β,Runx2 and Osterix protein expression levels were detected by western blot assay. RESULTS AND CONCLUSION:(1)Liuwei Dihuang Pill-containing serum culture reversed the decrease in alkaline phosphatase activity of MC3T3E-1 cells induced by titanium particles,increased the alizarin red staining and calcification of MC3T3E-1 cells,increased the expression of osteogenesis-related genes in MC3T3E-1 cells,and increased the expression of proteins related to the Wnt/β-catenin signaling pathway.(2)These findings indicate that Liuwei Dihuang Pill-containing serum can reverse the inhibitory effect of titanium particles on the differentiation and mineralization of osteoblasts,upregulate the expression of osteogenesis-related genes,and its mechanism is related to the regulation of Wnt/β-catenin signaling pathway,suggesting that Liuwei Dihuang Pill is expected to become an effective drug for preventing aseptic loosening of artificial joints.
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BACKGROUND:Recent studies have shown that the Notch signaling pathway plays a varying role in osteoporosis,and in-depth research in this field is of great significance to the prevention and treatment of osteoporosis.Traditional Chinese medicine has become the focus of research in today's society due to its obvious multi-faceted,multi-level benefits in alleviating osteoporosis with less adverse effects. OBJECTIVE:To analyze and summarize domestic and international literature to further understand the connection between the Notch signaling pathway and osteoporosis and to elucidate the mechanism by which traditional Chinese medicine prevents and treats osteoporosis via the Notch signaling pathway. METHODS:CNKI,WanFang,and VIP were searched with the keywords of"Notch,osteoporosis,osteoblasts,osteoclasts,bone marrow mesenchymal stem cells,signaling pathway,traditional Chinese medicine,pill,experiment"in Chinese.PubMed,Nature,and Embase were retrieved using the keywords of"Notch,osteoporosis,osteoblasts,osteoclasts,mesenchymal stem cells,signal pathway,traditional Chinese medicine,pill,experiment"in English.The search time was from database inception to October 2022. RESULTS AND CONCLUSION:The Notch signaling pathway plays a role in the development and progression of osteoporosis to varying degrees by regulating the differentiation and proliferation of mesenchymal stem cells,osteoblasts and osteoclasts.The Notch signaling pathway regulates the proliferation and differentiation of mesenchymal stem cells,osteoblasts and osteoclasts by directly or indirectly regulating key cytokines such as Notch1,Jagged1,Hes,Hey,macrophage colony-stimulating factor and nuclear factor-κB receptor-activating factor ligand,which in turn promotes or inhibits bone formation and ultimately has a certain effect on the prevention and treatment of osteoporosis.The active ingredients of Chinese herbs are mostly extracted from herbs for kidney tonifying,such as Epimedium,Cortex Eucommiae,Malaytea Scurfpea Fruit,Eleutherococcus Senticosus,Ligustrum Lucidum.Moreover,herbal compounds and preparations have the effect of tonifying kidney and strengthening bone,which provides more herbal options and directions for the subsequent study of Notch signaling pathway toward the prevention and treatment of osteoporosis.Current studies on traditional Chinese medicine mainly focus on active ingredients and single herbal extracts,with relatively few clinical trials on Chinese herbal compounds and preparations.Fewer studies have been conducted on the regulation of Notch signaling pathways by acupuncture,manipulation,and integrated Chinese and Western medicine to prevent and treat osteoporosis.Therefore,there is a need to explore the mechanisms by which traditional Chinese medicine technology-based therapies and integrated Chinese and Western medicine regulate the Notch signaling pathway to treat osteoporosis.
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BACKGROUND:Sema3A is a power secretory osteoprotective factor.However,studies about Sema3A-modified dental pulp stem cells(Sema3A-DPSCs)are rare. OBJECTIVE:To explore the osteogenic differentiation ability of Sema3A-DPSCs and their regulatory effect on the osteogenic differentiation of the pre-osteoblast cell line MC3T3-E1. METHODS:First,Sema3A-DPSCs were constructed using a lentivirus infection system carrying the Sema3A gene.Control lentivirus-treated DPSCs(Vector-DPSCs)were used as controls.Sema3A-DPSCs or Vector-DPSCs were co-cultured with proosteoblast line MC3T3-E1 at the ratio of 1∶1 and 1∶3 for 24 hours.Finally,the Sema3A-DPSCs,Vector-DPSCs and their co-cultured cells with MC3T3-E1 were cultured for osteogenic induction and differentiation.Osteogenic gene expression was detected by alkaline phosphatase staining,alizarin red staining and real-time quantitative RT-PCR to evaluate osteogenic differentiation ability. RESULTS AND CONCLUSION:(1)Sema3A mRNA and protein expression levels in Sema3A-DPSCs were significantly up-regulated.The level of secreted Sema3A in cell supernatant was up-regulated.(2)Compared with the Vector-DPSCs,mRNA expressions of osteogenic genes alkaline phosphatase,Runt-related transcription factor 2,osteocalcin and Sp7 transcription factors in Sema3A-DPSCs were up-regulated;the activity of alkaline phosphatase was enhanced,and the formation of mineralized nodules increased.(3)There were no obvious differences in proliferation between Sema3A-DPSCs and Vector-DPSCs.(4)Compared with MC3T3-E1/Vector-DPSCs co-culture system,the expression of MC3T3-E1 osteogenic genes was up-regulated,and the total alkaline phosphatase activity was enhanced and more mineralized nodules were formed in the MC3T3-E1/Sema3A-DPSCs co-culture system.(5)The results suggest that overexpression of Sema3A can enhance the osteogenic differentiation of DPSCs.Overexpression of Sema3A in DPSCs can promote osteogenic differentiation of MC3T3-E1 in the DPSCs/MC3T3-E1 co-culture system.
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BACKGROUND:Bone defects are caused by many factors,such as inflammation,tumor,trauma or bone diseases.Erythropoietin can promote the differentiation of mesenchymal stem cells into osteoblasts and osteoclasts and act on vascular endothelial cells to induce angiogenesis and accelerate the repair of bone and cartilage defects.Erythropoietin is a growth factor with potential application in bone tissue engineering construction. OBJECTIVE:To expound the application and potential mechanism of erythropoietin in bone tissue engineering. METHODS:The first author searched the related articles published in CNKI,WanFang,VIP,and PubMed databases from 2004 to 2022 by computer.Search terms were"erythropoietin,bone defect,bone regeneration,angiogenesis,osteogenesis,osteoblast,osteoclast,bone tissue engineering"in Chinese and English.Finally,64 articles were included for review. RESULTS AND CONCLUSION:(1)Erythropoietin can directly act on osteoblasts and osteoclasts in the bone marrow microenvironment by promoting the differentiation of mesenchymal stem cells into osteoblasts,osteoclasts,adipocytes,nerve cells and stromal cells.The activation of Wnt/β-catenin,hypoxia-inducible factor 1α/vascular endothelial growth factor,p38 MAPK and EphrinB2/EphB4 signaling pathways mediates the osteogenic differentiation of mesenchymal stem cells.(2)Erythropoietin can not only regulate the production of erythrocytes to alter the oxygen-carrying capacity of blood but also stimulate vascular endothelial cells to promote angiogenesis.The new blood vessels can carry oxygen,nutrients,growth factors,and bone progenitor cells necessary for osteogenesis to the osteogenic site,thereby promoting bone formation and fracture healing.(3)Currently,erythropoietin is being used as a growth factor with osteogenic and angiogenic effects in various types of scaffold materials such as chitosan,polycaprolactone,bioceramics,and nanofibers through various drug delivery methods.Erythropoietin,along with other growth factors such as bone morphogenetic protein-2 and bone morphogenetic protein-9,has been applied to the surface of scaffold materials to participate in the repair of bone defects.Erythropoietin has demonstrated excellent practicality in the construction of new tissue-engineered bone and has potential clinical application value.
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BACKGROUND:Toll-like receptors are an important class of pattern recognition receptors that have important functions in pathogen immunity and cytokine synthesis by recognizing specific molecular patterns.Previous studies have found that different types of bone tissue cells also express Toll-like receptors.Activation or inhibition of Toll-like receptors can have significant effects on osteoblast and osteoclast function through multiple pathways. OBJECTIVE:To summarize the expression and action pathways of Toll-like receptors in osteoblasts and osteoclasts,in order to further elucidate the biological mechanisms involved in the regulation of Toll-like receptors under physiological and pathological conditions. METHODS:Relevant literature was retrieved from databases such as PubMed and CNKI as of December 2022.The Chinese and English search terms included"Toll-like receptor,osteoblast,osteoclast,mesenchymal stem cells,macrophage,cytokine,signaling pathway".According to the research needs,the corresponding criteria were established to screen the final literature. RESULTS AND CONCLUSION:(1)Toll-like receptors could directly regulate osteoblast and osteoclast differentiation through the activation of related signaling pathways.(2)Toll-like receptor activation induces cytokine production and exerts regulatory effects.(3)Toll-like receptor activation can affect the survival and migration ability of osteoblasts and osteoclasts.(4)Toll-like receptors in osteoblasts and osteoclasts are activated in certain diseases and pathological settings and are involved in intercellular interactions.
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BACKGROUND:The nuclear factor-κB signaling pathway plays an important role in the pathogenesis of osteoporosis.In recent years,increasing studies have shown that terpenoid herbal monomer compounds can inhibit the activity of bone resorbing cells and promote the differentiation of bone forming cells via the nuclear factor-κB signaling pathway,thus reducing bone resorption and increasing bone formation,which has certain preventive and therapeutic effects on osteoporosis. OBJECTIVE:By analyzing and summarizing the domestic and international literature,to investigate the relationship between nuclear factor-κB signaling pathway and osteoporosis in depth,elucidate the mechanism of terpenoid monomer compounds in regulating the nuclear factor-κB signaling pathway to prevent osteoporosis,and systematically summarize the terpenoid monomer compounds targeting to regulate the nuclear factor-κB signaling pathway to prevent osteoporosis. METHODS:According to the proposed inclusion and exclusion criteria,two researchers searched for relevant articles published from database inception to December 2022 in CNKI and PubMed using the search terms"NF-κB,osteoporosis,osteoblasts,osteoclasts,angiogenesis,traditional Chinese medicine,terpenoid"in Chinese and English,respectively.A third researcher summarized and organized the literature and 75 articles were finally included for a systematic review. RESULTS AND CONCLUSION:The nuclear factor-κB signaling pathway mediates the onset and progression of osteoporosis by regulating the differentiation and proliferation of osteoblasts and osteoclasts,as well as angiogenesis.Activation of the nuclear factor-κB signaling pathway negatively regulates the proliferation and differentiation of osteoblasts.Activation of the nuclear factor-κB signaling pathway enhances osteoclast activity and inhibits osteoblast growth,thereby inhibiting compensatory bone production to maintain bone homeostasis.However,over-activation of the nuclear factor-κB signaling pathway can lead to osteoporosis.The nuclear factor-κB signaling pathway is involved in the"angiogenesis-osteogenesis"coupling by upregulating the expression levels of cytokines such as angiopoietin-1,platelet-derived growth factor BB and vascular endothelial growth factor,which promote the growth of blood vessels in bone.The terpenoid herbal monomer compounds are used in the field of tissue engineering to promote the proliferation and differentiation of bone cells,thereby promoting the growth and repair of bone tissue.Terpenoid herbal monomer compounds can prevent and treat osteoporosis by inhibiting the degradation of nuclear factor-κB inhibitor,blocking nuclear factor-κB/p65 phosphorylation and nuclear translocation,thereby weakening the nuclear factor-κB signaling pathway,promoting osteoblast differentiation and inhibiting osteoclast formation.Currently,research on the regulation of nuclear factor-κB signaling pathway by monomeric compounds of terpenoids to prevent osteoporosis is mainly based on in vitro cellular experiments and animal models,and there is a lack of research on the complex physiological and pathological processes in humans.In the future,more clinical trials and studies are needed to further clarify the mechanism of action and efficacy of the nuclear factor-κB signaling pathway involved in the intervention of osteoporosis.
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BACKGROUND:Nanostructure modification of pure titanium surface is a hot research field of titanium implant surface treatment. OBJECTIVE:To evaluate the effect of nano-modified titanium surface treated with alkali heat treatment on early adhesion and growth of osteoblasts. METHODS:Four-grade pure titanium sheets with a diameter of 15 mm and a thickness of 1.5 mm were taken and processed in three groups:the smooth treatment group was polished step by step with 250 mesh,800 mesh,and 1 500 mesh silicon carbide sandpaper.In the sandblasting group,the smoothed titanium sheet was sandblasted with 100 μm Al2O3 particles at 0.45 MPa pressure,and then the acid etching was carried out.In the alkali heat treatment group,the smoothed titanium sheet was placed in the reactor,immersed in 10 mol/L NaOH solution,and heated in the oven at 100 ℃for 12 hours.The surface morphology,roughness,and hydrophilicity of three groups of titanium sheets were measured.MG63 osteoblasts were inoculated on the surface of three groups of titanium tablets,and the adhesion of the cells was observed by immunofluorescence staining. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the surface of titanium sheets in the smooth treatment group had uniform scratches;the surface of titanium sheets in the sandblasting group was uneven,and the surface of titanium sheets in the alkali heat treatment group had uniform nanoscale three-dimensional pore morphology.The roughness value of the titanium sheets in sandblasting and alkali heat treatment groups was higher than that in the smooth treatment group(P<0.05),and the water contact angle was lower than that in the smooth treatment group(P<0.05).(2)Immunofluorescence staining after 3 and 6 hours of inoculation of MG63 cells showed that the number of adhesion cells on the surface of the titanium sheet in the sandblasting group and alkali heat treatment group was higher than that in the smooth treatment group(P<0.05).Immunofluorescence staining 12 hours after inoculation showed that compared with the smooth treatment group,the actin skeleton of cells on the surface of titanium sheets in the sandblasting group and alkali heat treatment group was more extended,and most cells extended stronger pseudopodia,which was conducive to subsequent intercellular signal transduction and intercellular interaction.(3)The results showed that the nanostructures with certain biological activity could be prepared on the surface of a titanium sheet by alkali heat treatment,which was conducive to the early adhesion of osteoblasts.
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BACKGROUND:With the aging of the global population,the incidence rate of osteoporosis is also increasing.It is very important to further understand its pathogenesis and propose new therapeutic targets.Recent studies have shown that ferroptosis is closely related to the pathogenesis of some bone diseases,such as inflammatory arthritis,osteoporosis and osteoarthritis. OBJECTIVE:To summarize the previous studies on the mechanism of ferroptosis in osteoporosis,so as to provide new therapeutic ideas and potential therapeutic targets for osteoporosis. METHODS:The first author used the computer to search the documents published from 2000 to 2022 in CNKI,WanFang,VIP,PubMed and Web of Science with the key words of"ferroptosis,osteoporosis,osteoblasts,osteoclasts,iron chelators,reactive oxygen species,nuclear factor erythroid 2-related factor 2,heme oxygenase-1,glutathione peroxidase 4,review"in Chinese and English.A total of 70 articles were finally included according to the inclusion criteria. RESULTS AND CONCLUSION:Ferroptosis is significantly different from necrosis,apoptosis and autophagy.In terms of cell morphology and function,it does not have the morphological characteristics of typical necrosis,nor does it have the characteristics of traditional apoptosis,such as cell contraction,chromatin condensation,the formation of apoptotic bodies and the disintegration of cytoskeleton.Contrary to autophagy,ferroptosis does not form a classical closed bilayer membrane structure(autophagic vacuole).Morphologically,ferroptosis is mainly manifested by obvious contraction of mitochondria,increased membrane density,and reduction or disappearance of mitochondrial cristae,which are different from other cell death modes.Iron overload can destroy bone homeostasis by significantly inhibiting osteogenic differentiation and stimulating osteoclast formation,leading to osteoporosis.Iron overload interferes with the differentiation of stem cells to osteoblasts,leading to a weakened osteoblast function and further imbalance of bone metabolism in the body,which eventually leads to osteoporosis.Stimulated by iron overload,osteoclast bone resorption is enhanced and bone loss exceeds new bone formation.Iron chelators have been proved to have osteoprotective effects by inhibiting osteoclast activity and stimulating osteogenic differentiation of osteoblasts.Its potential mechanism is related to inhibiting osteoclast differentiation and promoting osteoblast differentiation.Antioxidants can prevent reactive oxygen species production and inhibit bone absorption,thus improving bone metabolism and effectively preventing osteoporosis.
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BACKGROUND:Studies have shown that imbalance of bone metabolism during glucocorticoid-induced osteonecrosis of the femoral head necrosis is closely related to oxidative stress. OBJECTIVE:To investigate the pathological mechanism by which oxidative stress-induced ferroptosis promote apoptosis in osteoblasts involved in steroid-induced osteonecrosis of the femoral head. METHODS:General data and serum specimens were collected from 47 patients with steroid-induced osteonecrosis of the femoral head.In addition,six femoral head specimens were collected from these patients.According to the Association Research Circulation Osseous(ARCO)staging system,serum specimens were grouped into ARCO Ⅱ,Ⅲ,and IV,while femoral head specimens were classified into ARCO Ⅲ and IV.Serum levels of malondialdehyde and superoxide dismutase 1 were measured.The protein expression of superoxide dismutase 1,glutathione peroxidase 4,Bcl-2 in the femoral head was detected and verified by Data independent acquisition(DIA)for quantitative sequencing,western blot and alkaline phosphate detection. RESULTS AND CONCLUSION:The ARCO stage of patients with steroid-induced osteonecrosis of the femoral head was independent of age,sex and necrotic side.The serum levels of malondialdehyde and superoxide dismutase 1 were higher in patients with ARCO stage Ⅲ compared with those with ARCO stage Ⅱ and IV.The results of DIA protein quantification showed that the function of differential proteins was mainly related to redox.The levels of superoxide dismutase 1,glutathione peroxidase 4,and Bcl-2 in the necrotic region were lower than in the normal region,as well as lower in ARCO stage IV than in ARCO stage Ⅲ.Western blot verified the results of DIA protein quantification.The alkaline phosphatase activity was lower in the necrotic region than in the normal region,as well as lower in ARCO stage IV than in ARCO stage Ⅲ.In the necrotic and sclerotic regions,the function of differential proteins was also related to redox,and superoxide dismutase 1,glutathione peroxidase 4,Bcl-2 protein expression and alkaline phosphatase activity were lower in the necrotic area than in the sclerotic region,as well as lower in ARCO stage IV than in ARCO stage Ⅲ.To conclude,glucocorticoids can influence the progression of steroid-induced osteonecrosis of the femoral head by upregulating oxidative stress levels,inducing osteoblast ferroptosis,and inhibiting osteogenic function.
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BACKGROUND:Tumor necrosis factor-α is a broadly acting inflammatory cytokine that plays an important role in the immune inflammatory response of the body.The current study concluded that tumor necrosis factor-α has significant biological effects on a variety of bone tissue cells. OBJECTIVE:To summarize the expression and action pathways of tumor necrosis factor-α in osteoblastic and osteoclastic cells to further elucidate the regulatory role of tumor necrosis factor-α on bone tissue cells. METHODS:PubMed and CNKI were searched until March 2023,and the Chinese search terms included"tumor necrosis factor α,osteoblast,osteoclast,osteoclast,osteoprogenitor";the English search terms included"TNF-α,osteoblast,osteoclast,osteocyte,osteoprogenitor cell".The corresponding criteria were established according to the research needs,and the final literature was screened.Finally,77 articles were included for review. RESULTS AND CONCLUSION:(1)Tumor necrosis factor-α is participating in regulating the recruitment,appreciation,and differentiation of osteoprogenitor cells,but leads to osteoprogenitor cell stripping and death under specific environments.It also participates in bone resorption directly or indirectly through secreted enzymes.(2)Tumor necrosis factor-α can increase the level of inflammatory factors in the environment by activating relevant signaling pathways in osteoclast lineage cells or directly induce the generation of osteoclasts in specific environments.(3)Tumor necrosis factor-α can inhibit osteogenic differentiation by activating nuclear factor-κB signaling pathway,inhibiting the expression of transcription factors such as RUNX2 and Osterix,and inducing apoptosis and necrotizing apoptosis in osteoblasts.(4)Tumor necrosis factor-α inhibits osteogenesis and promotes osteoclastogenesis by activating the nuclear factor-κB signaling pathway in osteocytes and inducing cytokines such as RANKL,SOST,and DKK1,while enhancing apoptosis of the osteocytes,as well as bone resorption around the apoptotic bone tissue.(5)Taken together,the effect of tumor necrosis factor-α in bone tissue is mainly to inhibit osteogenesis and promote osteoclastosis.The biological effect of tumor necrosis factor-α in bone tissue cells is usually dependent on the activation of tumor necrosis factor receptor and nuclear factor-κB signaling pathways.(6)The interaction of tumor necrosis factor-α with other tissue cell types surrounding bone tissue and its role in bone immune regulation still deserve attention in future studies.
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BACKGROUND:Bone formation is the process by which osteoblasts synthesize and secrete osteoid and promote its mineralization,which generally involves mechanical signal transduction.Osteoblasts are primarily regulated by mechanical factors such as gravity,compressive stress,tensile stress,fluid shear stress,and hydrostatic pressure in vivo,and different mechanical stimuli modulate the proliferation,differentiation,and apoptosis of osteoblasts through various mechanisms,including hormones,cytoskeletal proteins,and microRNAs.By clarifying the effects of biomechanical forces on osteoblasts,it provides ideas and a reference basis for the treatment of osteometabolic diseases involving osteoblasts. OBJECTIVE:To review the effects of different biomechanical forces on the biological characteristics of osteoblasts. METHODS:We conducted a literature search using PubMed,Web of Science,FMRS,CNKI,and WanFang databases for relevant publications published from 2000 to 2023,covering basic research and tissue engineering studies related to the effects of biomechanical forces on osteoblasts.Ultimately,a total of 70 articles were reviewed. RESULTS AND CONCLUSION:Different biomechanical forces have an impact on the biological characteristics of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are dependent on the intensity and duration of the applied force.Specifically,the effects are as follows:(1)Under microgravity conditions,osteoblast proliferation and differentiation are inhibited,resulting in a decrease in bone density and the development of osteoporosis.(2)Compared to microgravity,hypergravity has a promoting effect on osteoblast proliferation.(3)The effects of compressive stress on osteoblasts are dependent on the loading intensity and time.Appropriate compressive stress can promote osteoblast proliferation and differentiation,which is beneficial for bone tissue formation and repair,while excessive compressive stress can cause osteoblast apoptosis and bone tissue destruction.(4)The biological effects of different types of tensile stress on osteoblasts differ.Studies have shown that a strain rate within the range of 0-12%has a promoting effect on osteoblast proliferation.(5)Fluid shear stress can promote osteoblast proliferation and differentiation and enhance the bone-inducing effect of biomaterials.(6)Static hydrostatic pressure can affect the biological behavior of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are closely related to the time and intensity of the pressure.Understanding the effects of different biomechanical forces on osteoblasts is of great significance for a deeper understanding of bone growth and maintenance mechanisms.
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BACKGROUND:Osteoporosis has a high incidence,leading to fracture and other complications.However,existing drugs have great side effects and are difficult to meet the clinical application. OBJECTIVE:To explore the effect and potential mechanism of fucoxanthin on osteoporosis induced by glucocorticoid. METHODS:Primary rat osteoblasts were inoculated in 6-well plates.When the cell fusion reached 80%,the cells were divided into four groups:the control group was cultured alone for 24 hours,the glucocorticoid group was intervened with dexamethasone for 24 hours,the fucoxanthin group was intervened with fucoxanthin for 24 hours,and the glucocorticoid + fucoxanthin group was intervened with dexamethasone and fucoxanthin at the same time for 24 hours.After intervention,cell proliferation,apoptosis,intracellular reactive oxygen species level,and protein expression of apoptosis-related proteins,bone formation-related proteins,and nuclear factor erythroid-2-related factor 2 were detected. RESULTS AND CONCLUSION:Cell counting kit-8 results showed that the cell viability was decreased in the glucocorticoid group compared with the control group(P＜0.05)but increased in the glucocorticoid+fucoxanthin group compared with the glucocorticoid group(P＜0.05).JC-1 mitochondrial membrane potential staining and flow cytometry assay showed that the percentage of apoptosis increased in the glucocorticoid group compared with the control group(P＜0.05)but decreased in the glucocorticoid+fucoxanthin group compared with the glucocorticoid group(P＜0.05).Western blot assay showed that compared with the control group,the protein expression of BAX and cleaved poly(ADP-ribose)polymerase was elevated in the glucocorticoid group(P＜0.05),and the protein expression of BCL2,type Ⅰ collagen α1 peptide chain,alkaline phosphatase,osteocalcin,and RUNX2 was decreased in the glucocorticoid group(P＜0.05).Compared with the glucocorticoid group,the protein expression of BAX and cleaved poly(ADP-ribose)polymerase was decreased(P＜0.05),and the protein expression of BCL2,type Ⅰ collagen α1 peptide chain,alkaline phosphatase,osteocalcin,and RUNX2 was elevated(P＜0.05)in the glucocorticoid+fucoxanthin group.Fluorescent probe assay showed an increase in reactive oxygen species level in the glucocorticoid group compared with the control group(P＜0.05)and a decrease in reactive oxygen species level in the glucocorticoid+fucoxanthin group compared with the glucocorticoid group(P＜0.05).Immunofluorescence staining and western blot assay showed that the protein expression of nuclear factor erythroid-2-related factor 2 in the glucocorticoid group was decreased compared with that in the control group(P＜0.05);and the protein expression of nuclear factor erythroid-2-related factor 2 in the glucocorticoid+fucoxanthin group was elevated compared with that in the glucocorticoid group(P＜0.05).To conclude,fucoxanthin can improve glucocorticoid-induced osteoblast apoptosis and the expression of bone formation-related molecules by activating nuclear factor erythroid-2-related factor 2.
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BACKGROUND:Steroid-induced osteonecrosis of the femoral head is a refractory disease in the field of orthopedics.There is no definitive idea to fully explain its pathogenesis.With the increased research on the active ingredients of Panax notoginseng interfering with the signaling pathways related to various diseases,the active ingredients of Panax notoginseng that treat steroid-induced necrosis of the femoral head via the regulation of relevant signaling pathways have gradually become a hot research topic. OBJECTIVE:To systematically summarize the literature on the pathological mechanism of steroid-induced osteonecrosis of the femoral head and the regulation of signaling pathways by the active ingredients of Panax notoginseng in recent years,thereby providing a reference for the follow-up study on the active ingredients of Panax notoginseng in the treatment of this disease. METHODS:CNKI,WanFang,and PubMed were searched for relevant literature with the key words of"glucocorticoid,steroid-induced osteonecrosis of the femoral head,pathological mechanism,signaling pathway,Panax notoginseng,active ingredient"in Chinese and English.Documents related to the pathological mechanism of steroid-induced osteonecrosis of the femoral head as well as related to the intervention of active ingredients of Panax notoginseng on the signaling pathway of steroid-induced osteonecrosis of the femoral head were retrieved.A total of 63 documents were finally included according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:The main ingredients of Panax notoginseng include Panax notoginseng saponins,ginsenoside,Panax notoginseng saponins,quercetin,kaempferol,etc.Panax notoginseng saponins,ginsenoside Rb1 and quercetin can promote bone repair and angiogenesis by acting on the transforming growth factor-β/bone morphogenetic protein pathway.Panax notoginseng saponins,ginsenoside CK and kaempferol can promote osteogenic differentiation and lipid metabolism by acting on the Wnt/β-catenin pathway.Panax notoginseng saponins and Panax notoginseng saponins R1/R2 act on the MAPK pathway to inhibit osteoclastogenesis and promote bone repair.Panax notoginseng saponins,ginsenoside Rb2 and quercetin can inhibit osteoclast proliferation and promote osteoblastic differentiation by acting on the RANKL/RANK/OPG pathway.Panax notoginseng saponins,quercetin and kaempferol can repair vascular injury and promote osteogenesis by acting on the hypoxia-inducible factor-1α pathway.Panax notoginseng saponins R1,quercetin combined with hydroxyapatite nanoparticles,Panax notoginseng saponins combined with polyethylene-L-lactic acid and other biomaterials have good research prospects in the treatment of steroid-induced osteonecrosis of the femoral head.The active ingredients of Panax notoginseng can regulate the signaling pathways related to steroid-induced osteonecrosis of the femoral head through various mechanisms,and play an active intervention role in the disease.However,the depth and breadth of relevant research are insufficient at present,and the future research should be based on the existing mechanism to explore the specific mechanism of Panax notoginseng regulating different pathways and the interaction between pathways,which will be beneficial to the multi-development of the active ingredients of Panax notoginseng in the treatment of steroid-induced osteonecrosis of the femoral head.
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BACKGROUND:Interleukin-8 is an important cytokine that has been found to play an important role in bone regeneration through multiple pathways. OBJECTIVE:To comprehensively review the action mechanism of interleukin-8 effects on bone regeneration to provide ideas for the following studies on interleukin-8. METHODS:By searching the China National Knowledge Infrastructure database for articles published from January 1999 to February 2023 and PubMed database for articles published from January 1985 to February 2023 reporting the role of interleukin-8 in bone-associated cells and vascularisation.Chinese and English search terms were"interleukin-8,bone repair,bone metabolism,mesenchymal stem cells,osteoblasts,osteoclasts,vascularization".The initial review yielded 508 articles in English and Chinese,and a total of 51 articles were included for review and analysis according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:According to the existing research,interleukin-8 can promote bone cell regeneration and assist bone healing through multiple pathways,which is mainly divided into three aspects:(1)Promote the proliferation and differentiation of bone cells such as mesenchymal stem cells and osteoblasts,and promote the development of cells in the direction of promoting bone healing;(2)interleukin-8 can promote angiogenesis and provide sufficient nutrition and oxygen for bone tissue,thus further improving the quality and stability of bone healing.(3)The appearance of interleukin-8 facilitates the expression of hypoxia-inducible factor-1α,vascular endothelial growth factor,and matrix metalloproteinase,which can create a microenvironment conducive to bone regeneration,thus promoting the regeneration and repair of bone tissue.In summary,interleukin-8 plays an important role in bone healing by promoting osteoblast proliferation and differentiation,facilitating angiogenesis and improving the mechanical properties of bone regeneration,as well as influencing bone metabolism through osteoclasts,mesenchymal stem cells,and other action sites.
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BACKGROUND:Heterotopic ossification of skeletal muscle is a clinically serious complication.For heterotopic ossification of skeletal muscles,the cells involved in the process of heterotopic ossification remain unclear. OBJECTIVE:To investigate the involvement of myocytes,fascia cells,and endothelial cells in the process of heterotopic ossification in skeletal muscle and to observe the cell origin of heterotopic ossification in skeletal muscle induced by bone morphogenetic protein 4. METHODS:Both C2C12 cells and the myotubes formed by the C2C12 cells in the induction medium were cultured,and 500 ng/mL bone morphogenetic protein 4 was added to the medium respectively,and whether the C2C12 cells and myotubes continued to proliferate within 10 days under the treatment were observed under a microscope.Myogenic cells(L6,derived from rats)and fibroblast-derived cells(derived from human)were co-cultured.After treatment with 500 ng/mL bone morphogenetic protein 4 and 10 ng/mL transforming growth factor-β,osteogenic and chondrogenic differentiation potential within 21 days were observed using Safranine O staining and Alcian blue staining.Using transgenic animal FVB/N-TgN(TIE2-LacZ)182Sato mice,15 μL of adeno-associated virus-bone morphogenetic protein 4(5×1010 PFU/mL)were implanted in the thigh muscle space of genetic mice for 10 and 14 days.X-gal staining was used to observe the formation of new blood vessel endothelium in the differentiated bone. RESULTS AND CONCLUSION:(1)Bone morphogenetic protein 4 caused myotube breakdown and increased C2C12 cell proliferation.Compared with other groups,the pure fibroblast-derived cell group had a higher area of positive alcian blue and safarin O staining(P<0.05)and a lower area of alkaline phosphatase staining(P<0.05),while the pure L6 group had a bigger area of alkaline phosphatase staining(P<0.05)but a smaller area of positive alcian blue and safarin O staining(P<0.05).(2)Transplantation of adeno-associated virus-bone morphogenetic protein 4-adsorbed gelatin sponge into FVB/N-TgN(TIE2-LacZ)182Sato mice resulted in heterotopic ossification.(3)X-gal staining results demonstrated that there was no obvious staining in chondrocytes and differentiated bones and Tie2+ endothelial cells did not participate in the formation of the alienated bone.(4)These findings verify that fibroblasts are the primary source of osteoblasts during the adeno-associated virus-bone morphogenetic protein 4-induced ectopic endochondral ossification in skeletal muscle,but myogenic cells are the main source of osteoblasts.Tie2+ endothelial cells might not be the cell source for cartilage and bone.
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BACKGROUND:Punicalagin has a wide range of effects and high safety,but its effect on osteoblasts and postmenopausal osteoporosis is unknown. OBJECTIVE:To investigate the effect of punicalagin on osteoblasts and postmenopausal osteoporosis. METHODS:The effect of punicalagin on the proliferation of MC3T3-E1 cells was detected.Punicalagin was added to the osteogenic induction medium to detect its effect on osteogenic differentiation.Punicalagin was used to treat ovariectomized rats and Micro CT scan and serum procollagen type 1 N-terminal propeptide test were performed after 3 months to detect the therapeutic effect. RESULTS AND CONCLUSION:Cell counting kit-8 assay showed that punicalagin could promote the proliferation of osteoblasts(P＜0.05).The results of qRT-PCR and western blot showed that punicalagin could promote the mRNA and protein expressions of alkaline phosphatase and Runx2 in osteoblasts(P＜0.05).The results of Micro CT scan and serological test showed that punicalagin could improve bone mineral density,bone volume fraction,trabecular thickness,trabecular number and procollagen type 1 N-terminal propeptide level of ovariectomized rats.To conclude,punicalagin can promote osteoblast proliferation and differentiation,and have therapeutic effects in postmenopausal osteoporosis rats.
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BACKGROUND:Upregulation of hedgehog protein signaling can increase the expression of osteoarthritis markers,Runx2,a disintegrin and metalloproteinase with thrombospondin motifs,collagen type X alpha 1,and matrix metalloproteinase 13,while inhibition of hedgehog proteins attenuates the severity of osteoarthritis.It is speculated that osteoarthritic chondrocytes can influence bone formation by affecting osteoblasts through the Indian hedgehog protein(IHH)signaling pathway. OBJECTIVE:To investigate the effect of human osteoarthritic chondrocytes on subchondral osteoblasts. METHODS:Tibial plateau specimens from patients with osteoarthritis were collected.Chondrocytes were extracted using enzymatic digestion,and osteoblasts were extracted using enzymatic pre-digestion + bone block method.Chondrocytes were identified by toluidine blue staining and immunofluorescence and osteoblasts were identified by alkaline phosphatase staining and immunofluorescence.Chondrocytes were cultured in sodium alginate beads to maintain chondrocyte phenotype and co-cultured with osteoblasts.The co-culture system was added with IHH signaling pathway inhibitor(cyclopamine,10 nmol/L)and activator(purmorphamine,10 nmol/L)separately.After 48 hours of co-culture,osteoblasts from each group were collected,mRNA expressions of Gli1,osteoprotegerin,Runx2,parathyroid hormone-related peptide,alkaline phosphatase,receptor activator of nuclear factor-kB ligand(RANKL)and osteocalcin were detected by qRT-PCR,and protein expressions of GLi1,oseoprotegerin and RANKL in osteoblasts were detected by western blot. RESULTS AND CONCLUSION:The mRNA expression levels of GLi1,osteoprotegerin and RUNX2 in osteoblasts were significantly increased,while the mRNA expression levels of parathyroid hormone-related peptide were decreased(P＜0.05)when co-cultured with human osteoarthritic chondrocytes.The mRNA and protein levels of Gli1 were significantly decreased after the addition of IHH signaling pathway inhibitor(cyclopamine)(P＜0.05),and the mRNA and protein levels of Gli1 were significantly increased after the addition of IHH signaling pathway activator(purmorphamine)(P＜0.05).Osteoprotegerin showed the same trend as Gli1 in the experiment.The osteoprotegerin/RANKL ratio followed the same trend as osteoprotegerin.To conclude,human osteoarthritic chondrocytes can promote the expression of Gli1,osteoprotegerin,Runx2 and other proteins in osteoblasts.The upregulation of osteoprotegerin is related to the IHH signaling pathway.Osteoarthritic chondrocytes can up-regulate the expression of osteoprotegerin in osteoblasts through the IHH signaling pathway and thus up-regulate the osteoprotegerin/RANKL ratio,which will contribute to bone formation in subchondral bone.
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BACKGROUND:Recent studies have shown that the occurrence and prevention of osteoporosis often focus on the cellular molecular level,and the mechanism of related signaling pathways is an important way to further understand osteoporosis.At present,traditional Chinese medicine has been proved to play a significant role in alleviating osteoporosis.Kaempferol as an emerging Chinese herbal extract has become the focus of clinical and basic research due to its anti-osteoporosis effectiveness and mechanism of action. OBJECTIVE:To further understand the mechanism underlying the anti-osteoporosis effect of kaempferol active monomer through regulation of related signaling pathways by analyzing and collating domestic and foreign literature. METHODS:"Kaempferol,osteoporosis,osteoblasts,osteoclasts,bone marrow mesenchymal stem cells,signaling pathways"were used as Chinese and English search terms to search CNKI,WanFang,VIP,PubMed,Web of Science and Embase databases for relevant literature published from database inception to February 2023. RESULTS AND CONCLUSION:Kaempferol affects the occurrence and progression of osteoporosis to varying degrees by participating in the regulation of differentiation,proliferation and apoptosis of bone marrow mesenchymal stem cells,osteoblasts and osteoclasts.Kaempferol can prevent and treat osteoporosis by regulating various signaling pathways.Kaempferol can promote the proliferation and differentiation of osteoblasts and inhibit the formation of osteoclasts by interfering with the Wnt/β-catenin signaling pathway to regulate β-catenin protein counting and the formation of β-catenin-TCf/LEF complex.Kaempferol interferes with the RANK/RANKL pathway to maintain the dynamic balance of osteoclasts and bone homeostasis.Kaempferol can promote bone formation by intervening with the PI3K/Akt signaling pathway to upregulate the levels of related osteogenic factors Runx2 and Osterix and promote bone cell calcification.Kaempferol interferes with osteoclast differentiation and inhibits reactive oxygen species activity by regulating the ER/ERK pathway.Kaempferol inhibits the expression of ERK,JNK,p38/MAPK and decreases reactive oxygen species production by interfering with the MAPK pathway,thus protecting osteogenesis.Kaempferol enhances the expression of osteogenic factors,bone morphogenetic protein-2,p-Smad1/5/8,β-catenin and Runx2,inhibits the expression of Peroxisome proliferation-activated receptor,and promotes the differentiation and proliferation of osteoblasts through the BMP/Smad pathway.
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BACKGROUND:The pathogenesis of osteoporosis is complex,and its essence is the weakening of bone formation and the enhancement of bone absorption caused by various reasons,resulting in the imbalance of bone metabolism.In recent years,N6-methyladenosine has been found(N6-methyladenosine,m6A)methylation can prevent and treat osteoporosis by regulating bone metabolism. OBJECTIVE:Taking the regulation of bone metabolism by m6A methylation as an entry point,to systematically sort out and summarize the research progress of m6A methylation in osteoporosis,so as to provide certain theoretical reference bases for the search of new therapeutic targets for osteoporosis. METHODS:CNKI,WanFang,VIP,PubMed,MEDLINE,Nature,and Cochrane databases were retrieved for relevant literature published from database inception to 2023.The keywords were"osteoporosis,m6A methylation,bone metabolism,bone marrow mesenchymal stem cells,osteoblasts,osteoclasts"in Chinese and English.Duplicates and obsolete non-referenced documents were excluded,and a total of 73 standard papers were included for further review. RESULTS AND CONCLUSION:m6A methylation can affect the activity and differentiation of bone marrow mesenchymal stem cells,osteoblasts,and osteoclasts through various pathways to regulate bone metabolism and prevent osteoporosis.The regulatory process of m6A methylation is extremely complex,and its related proteins play different roles in different cells.Even in the same kind of cells,the same type of proteins may have radically different roles,regulating different physiological and pathological processes.
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BACKGROUND:Careful regulation of bone immune response during repair of bone scaffold is important for bone regeneration. OBJECTIVE:To review the influence of bone immune response on bone repair and the design of bone tissue engineering scaffold with regulating bone immune function and its application in bone repair. METHODS:Relevant articles published from 1973 to 2023 were retrieved from Science Direct,PubMed,Web of Science,and CNKI databases.English search terms were"osteoimmunology,macrophages,bone repair materials,bone scaffold,bone defects,bone regeneration".Chinese search terms were"bone immunity,macrophages,bone repair material,bone stent,bone defect,bone regeneration".Totally 80 articles of the latest research progress in this field were summarized and analyzed. RESULTS AND CONCLUSION:(1)A detailed review was conducted on the important time points in the origin and development process of bone immunity,and it was explained that macrophages,as important members of the bone immune regulatory system,can be divided into two phenotypes:M1(pro-inflammatory)and M2(anti-inflammatory),and play a key role in different stages of bone regeneration.During the inflammatory phase,M1 type macrophages can activate osteoclasts,initiate tissue repair processes,and participate in the reconstruction of bone microvascular networks.On the other hand,during the bone tissue regeneration process in the later stages of inflammation,sustained high expression of M1 type macrophages can hinder the formation of new bones.During the repair phase,M2 macrophages can secrete osteogenic cytokines,stimulate osteogenic differentiation and mineralization of bone marrow mesenchymal stem cells,and promote bone formation.On the other hand,long-term activation of M2 macrophages can increase the secretion of fibrogenic molecules,leading to excessive formation of scar tissue and delaying the healing process.Therefore,regulating macrophages to undergo phenotype transformation at appropriate stages and constructing an immune microenvironment beneficial for osteogenesis has great significance for bone regeneration.(2)In the process of designing bone scaffolds with bone immune regulation characteristics,the physical and chemical properties such as scaffold roughness,pore structure,stiffness,hydrophilicity,surface charge,and surface functional groups can be changed to affect non-specific protein and cell adhesion,thereby affecting the interaction between bone scaffolds and the immune system.By designing surface functional coatings of bioactive substances such as hydroxyapatite,bioactive glass,metal ions,extracellular matrix,drugs,cytokines,and exosomes,the immune microenvironment can be actively regulated by releasing bioactive substances after implantation into the body,affecting macrophage polarization and crosstalk between macrophages and bone cells,and promoting more M2 polarization of macrophages,so as to build a bone immune microenvironment that is conducive to bone regeneration.(3)Based on the research and development of bone tissue engineering scaffolds,in addition to focusing on the direct regulatory factors of stem cell osteogenic differentiation,this article also proposes that attention should be paid to the management of the immune microenvironment of stem cell differentiation.By regulating the appropriate bone immune microenvironment,more stem cell osteogenic differentiation can be induced;the osteogenic efficiency of the scaffold can be enhanced,and the concept of"bone immune regulatory characteristics"can be condensed;deeply elucidated the multi-directional regulatory role of the bone immune microenvironment and introduced the existing strategies for changing the physicochemical properties and surface functional coating of scaffolds to endow them with bone immune regulatory potential,providing new ideas for guiding the development of a new generation of bone tissue engineering scaffolds with bone immune regulatory characteristics.However,the bone immune microenvironment is a dynamic equilibrium state,and most of the existing regulatory strategies do not consider the dynamic matching of regulation.Therefore,the research and development of intelligent bone immune regulatory scaffolds with efficient and targeted regulation of the immune microenvironment will be a key focus of attention for scholars in future.