Objective:To discuss the effect of acupuncture on the differentiation and apoptosis of quadriceps muscle satellite cells in model rats with knee osteoarthritis(KOA),and to clarify its related mechanism.Methods:A total of 40 SPF-grade rats were selected and randomly divided into control group,model group,celecoxib group,and acupuncture group,with 10 rats in each group.The rats in control group only underwent joint cavity incision followed by suturing,while the rats in model group,celecoxib group,and acupuncture group were used to replicate the KOA models.The maximum circumference of the femoral segment of the affected limb,rat body mass,and quadriceps wet weight of the rats in various groups were measured;the quadriceps wet weight maintenance rate and quadriceps wet weight/body mass ratio of the rats in various groups were calculated.HE staining was used to observe the pathomorphology of articular cartilage and quadriceps muscle tissue of the rats in various groups;terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick end labeling(TUNEL)method was used to detect the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in various groups;immunofluorescence method was used to detect the protein expression levels of interleukin-6(IL-6),Janus kinase(JAK),and signal transducer and activator of transcription 3(STAT3)in quadriceps muscle tissue of the rats in various groups;Western blotting method was used to detect the expression levels of IL-6/JAK/STAT3 signaling pathway proteins,and muscle satellite cells,and apoptosis-related proteins in quadriceps muscle tissue of the rats in various groups.Results:Compared with control group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in model group were significantly decreased(P<0.05);compared with model group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in acupuncture group were significantly increased(P<0.05).The HE staining results showed that the knee articular cartilage of the rats in control group remained intact,chondrocytes were aggregated and horizontally arranged with smooth edges,and quadriceps muscle cells were long cylindrical,orderly arranged,and regular in shape;in model group,the knee articular cartilage was thinner with rough edges,reduced number of cartilage layers,and disordered arrangement,and the quadriceps muscle fibers were disorganized,with some muscle fiber dissolution and muscle cell membrane damage,accompanied by muscle fiber fragments and a large amount of inflammatory exudate;in celecoxib group,the morphology of knee articular cartilage was generally normal,occasionally with irregular cartilage arrangement and reduced thickness,sporadically visible necrotic chondrocytes,quadriceps muscle fibers and sarcolemma were relatively intact,new muscle fibers appeared,some muscle fiber edges were blurred,accompanied by a small amount of cell debris and mild inflammatory infiltration;in acupuncture group,the knee articular cartilage structure remained intact with smooth edges,occasionally rough edges,and chondrocytes were aggregated and orderly arranged.The TUNEL assay results showed that compared with control group,the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in model group were significantly increased(P<0.05);compared with model group,the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly decreased(P<0.05);compared with celecoxib group,the apoptosis index in articular cartilage and quadriceps muscle tissue of the rats in acupuncture group were significantly decreased(P<0.05).The immunofluorescence assay results showed that compared with control group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in model group were significantly decreased(P<0.05);compared with model group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05).The Western blotting results showed that compared with control group,the expression levels of IL-6,JAK,STAT3,paired box transcription factor 7(Pax7),Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in model group were significantly decreased(P<0.05);compared with model group,the expression levels of IL-6,JAK,STAT3,Pax7,Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the expression levels of IL-6,JAK,STAT3,Pax7,Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05).Compared with control group,the expression levels of B-cell lymphoma 2(Bcl-2),B-cell lymphoma-xl(Bcl-xl),and myeloid cell leukemia 1(MCL1)proteins in quadriceps muscle tissue in model group were significantly decreased(P<0.05),and the expression levels of Bcl-2-associated X protein(Bax)and cysteinyl aspartate specific proteinase-3(Caspase-3)proteins were significantly increased(P<0.05);compared with model group,the expression levels of Bcl-2,Bcl-xl,and MCL1 proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05),and the expression levels of Bax and Caspase-3 proteins were significantly decreased(P<0.05);compared with celecoxib group,the expression levels of Bcl-2,Bcl-xl,and MCL1 proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05),and the expression levels of Bax and Caspase-3 proteins were significantly decreased(P<0.05).Conclusion:Acupuncture can promote the differentiation of quadriceps muscle satellite cells and inhibit muscle cell apoptosis in the model rats with KOA,and the mechanism may be related to the up-regulation of expressions of IL-6,JAK,and STAT3 proteins in the quadriceps muscle tissue.

Objective To investigate the effects of meridian and tendon acupuncture on the mitochondrial apoptosis of quadriceps femoris muscle cells in model rats of knee osteoarthritis(KOA);To explore its mechanism for the treatment of KOA.Methods Totally 40 SPF healthy male Wistar rats were randomly divided into sham-operation group(10 rats)and modeling group(30 rats).The modified Hulth method was used to establish a KOA rat model.The model rats were randomly divided into model group,celecoxib group and meridian and tendon acupuncture group,with 9 rats in each group.Corresponding intervention measures were given to each group for 14 consecutive days.Improved Lequesne MG score was used for evaluating knee joint function in rats,measuring thigh circumference,quadriceps femoris wet weight,wet weight maintenance rate and wet weight ratio of the affected limb,HE staining was used to observe the morphology of quadriceps femoris tissue,TUNEL method was used to detect apoptosis of quadriceps femoris cells,immunofluorescence was used to detect the expressions of reactive oxygen species(ROS),superoxide dismutase(SOD),Caspase-3 and Caspase-9 in quadriceps femoris muscle tissue,fluorescence double staining method was used to detect the co-expression of ROS and Caspase-3 in quadriceps femoris tissue,Western blot was used to detect the expressions of apoptosis related proteins in quadriceps femoris tissue.Results Compared with the sham-operation group,the improved Lequesne MG score of the knee joint in the model group rats increased(P<0.05),the circumference of the thigh,wet weight of the quadriceps femoris,wet weight maintenance rate and wet weight ratio of the affected limb decreased(P<0.05),the arrangement of quadriceps femoris muscle fibers was disordered and loose,with some muscle fibers dissolved and necrotic,accompanied by a large amount of inflammatory exudate,an increase in lymphocytes,and an increase in cell apoptosis index(P<0.05),the expressions of ROS,Caspase-3 and Caspase-9 in quadriceps femoris tissue increased,while the expression of SOD decreased(P<0.05),the protein expressions of Bcl-2,Bcl-XL,Bax,Cytochrome C(CytC),Caspase-3 and Caspase-9 in quadriceps femoris tissue increased(P<0.05).Compared with the model group,the improved Lequesne MG scores of the knee joint in the celecoxib group and the meridian and tendon acupuncture group decreased(P<0.05),while thigh circumference,quadriceps femoris wet weight,wet weight maintenance rate,wet weight ratio increased(P<0.05),the structure of quadriceps femoris muscle fibers was normal,the muscle membrane was relatively intact,the apoptosis index decreased(P<0.05),the expressions of ROS,Caspase-3 and Caspase-9 in quadriceps femoris tissue decreased,while the expression of SOD increased(P<0.05),the protein expressions of Bcl-2,Bcl-XL,Bax,CytC,Caspase-3 and Caspase-9 in quadriceps femoris muscle tissue decreased(P<0.05),and the expression trend of ROS and Caspase-3 in fluorescent double staining was consistent.Conclusion Meridian and tendon acupuncture can reduce ROS in the quadriceps femoris tissue of KOA model rats,inhibit the expressions of mitochondrial apoptosis-related proteins,thereby improving skeletal muscle strength,and play a certain therapeutic role.

Objective: To explore the relative importance of different food attributes and levels in food decision making of school aged children, and to understand their meal preferences, so as to provide the evidence for formulating precise intervention strategies for dietary behaviours of school aged children. Methods: From May to June 2024, a total of 854 children aged 11 to 15 years old were selected from 2 middle schools (each school in urban and rural areas) in both Hubei Province and Anhui Province by stratified cluster random sampling method to conduct a D-optimal discrete choice experiment. The mixed Logit model was used to analyze children s preference for meal attributes and different levels, and to calculate the relative importance (RI) of attributes and willingness to pay (WTP) in meal choices. Results: The included five food attributes had statistical significance on meal choice of school aged children ( P <0.05). The relative importance of food attributes affecting the meal choices of school aged children in descending order were dining mode ( RI =31.26%), food varieties ( RI =30.56%), cooking method( RI =23.84%), taste( RI =8.06%) and price ( RI =6.27%). Among them, school aged children preferred home cooked meals ( β =0.74) (WTP=86.3 yuan),varied foods(grain/tubers+vegetables+fish, meat, eggs and beans) ( β =0.61) (WTP=71.9 yuan), fried/roasted cooking ( β =0.51) and spicy taste ( β =0.33).Price was negatively correlated with meal choices( β =-0.01) ( P <0.05). Based on residential area and body mass index (BMI), the stratified analysis showed that dining mode was highest in the relative importance for rural children with overweight and obese children ( RI =31.28%,34.17%), both of whom preferred home cooked meals ( β =0.76, 0.91), and meals containing fish, meat, eggs and beans with grain/tubers or grain/tubers and vegetables in terms of food choice (area: β =0.53, 0.53 ; BMI: β =0.55, 0.56) ( P <0.05). Conclusions School aged children have different preferences for different attributes of meals. The quality of school meals should be improved,the cost of buying healthy meals should be reduced,targeted family health education should be carried out,and healthy cooking methods should be advocated.

Objective To explore the mechanism of Danggui Sini Decoction in treating knee osteoarthritis(KOA)by using network pharmacology,combined with in vitro experimental verification.Methods The active components of Danggui Sini Decoction were retrieved and screened through TCMSP,CNKI and PubMed databases,and their corresponding targets were predicted using the SwissTarget Prediction platform.KOA related targets were retrieved from GeneCards and OMIM databases.Intersection of drug targets and KOA targets was obtained,and key components,core targets,and their related biological mechanisms were identified through network topology analysis,GO and KEGG pathway enrichment analysis.Molecular docking was used to verify the degree of binding between key components and core targets.Danggui Sini Decoction containing serum was prepared,and an in vitro KOA model was constructed by inducing rat articular chondrocytes with lipopolysaccharide.The CCK-8 method was used to screen for the optimal concentration of drug containing serum intervention,fluorescent probes were used to detect intracellular ROS content,immunofluorescence was used to detect NF-κB p65 nuclear translocation,RT-qPCR was used to detect the expressions of IL-6,IL-1β and TNF-α mRNA,Western blot was used to detect the expression of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),NF-κB p65 and p-NF-κB p65 proteins.Results The results of network pharmacology analysis indicated that the treatment of KOA with Danggui Sini Decoction may involve regulating Toll like receptors,MAPK,TNF,apoptosis and other inflammatory and aging signaling pathways,compounds such as quercetin,kaempferol and glycyrrhizin may play important roles.Core targets included IL6,IL1B,TNF,TLR4,NFKB1,JUN,MAPK1,RELA.In vitro experiments showed that compared with the blank group,the ROS content in chondrocytes of the model group significantly increased(P<0.01),NF-κB p65 protein was significantly nuclear translocation(P<0.01),and mRNA expressions of IL-6,IL-1β,TNF-α mRNA and protein expressions of TLR4,MyD88 and p-NF-κB p65 significantly increased(P<0.01);compared with the model group,the intervention of Danggui Sini Decoction containing serum could significantly reduce intracellular ROS content(P<0.05),inhibit NF-κB p65 nuclear translocation(P<0.01),and reduce the expression of inflammatory factor mRNA and related proteins(P<0.05,P<0.01).Conclusion Danggui Sini Decoction can significantly reduce the inflammatory response of rat articular chondrocytes induced by lipopolysaccharide and exert therapeutic effects on KOA.Its mechanism may be related to the inhibition of TLR4/MyD88/NF-κB pathway.

Objective To explore the mechanism of acupuncture protection of quadriceps muscle cells in knee osteoarthritis model rats based on Piezo1/YAP/Caspase3 axis.Methods 40 SPF grade Wistar rats were selected and adaptively fed for 7 days before being divided into three groups:sham surgery group,model group,western medicine group,and acupuncture group,with 10 rats in each group,according to a random control table.The model group,Western medicine group,and acupuncture group used the modified Hulth method to construct knee osteoarthritis models,while the sham surgery group only cut open the joint cavity and sutured it.After successful model replication,the sham surgery group was given physiological saline by gavage,the western medicine group was given celecoxib solution by gavage,and the acupuncture group was given acupuncture at the infrapatellar,crane top,and blood sea levels.Each group was intervened once a day for 14 consecutive days.During the treatment period,the rats continued to undergo treadmill training.After the intervention,the hematoxylin eosin staining method(HE)was used to detect the morphological changes of various rat quadriceps muscle tissues and articular cartilage;TUNEL method was used to detect apoptosis of quadriceps muscle cells,immunofluorescence method was used to detect the protein expression of Piezo1,YAP,and p-YAP in quadriceps muscle cells,Western blot method was used to detect the expression of anti apoptotic proteins CTGF,AREG,Gli2,AFP in quadriceps muscle tissue,as well as the protein expression levels of apoptosis related proteins Bcl-2,Bcl-xl,Bax,cytc,and Caspase3.Results Compared with the model group,the western medicine group and the acupuncture group had higher thigh circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight to body weight ratio(P<0.05).Compared with the western medicine group,the acupuncture group had higher thigh circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight to body weight ratio(P<0.05).Compared with the model group,the apoptosis index of the quadriceps muscle in the Western medicine group and acupuncture group rats was lower,and the apoptosis index of the quadriceps muscle in the acupuncture group was lower(P<0.05).Compared with the model group,the Western medicine group and acupuncture group showed higher expression of Piezo1 and p-YAP proteins in the quadriceps femoris muscle tissue,lower expression of YAP protein,higher expression of CTGF,AREG,Gli2,AFP proteins,higher expression of Bcl-2 and Bcl-xl proteins,and lower expression of Bax,cytc,and Caspase3 proteins(P<0.05).Compared with the Western medicine group,the acupuncture group showed higher expression of Piezo1 and p-YAP proteins in the quadriceps muscle tissue,lower expression of YAP protein,higher expression of CTGF,AREG,Gli2,AFP proteins,higher expression of Bcl-2 and Bcl-xl proteins,and lower expression of Bax,cytc,and Caspase3 proteins(P<0.05).Conclusion Acupuncture increases the expression of Piezo1 protein in the quadriceps femoris muscle of knee osteoarthritis model rats,promotes the phosphorylation of YAP into the nucleus,thereby promoting proliferation,anti apoptotic proteins CTGF,AREG,Gli2,and AFP protein expression,inhibiting Caspase3-dependent mitochondrial apoptosis,and protecting muscle cells.

Objective:To investigate the protective effect of PSD95 on neurobehavioral abnormalities and synaptic damage in cortex induced by hypoxia exposure in mice.Methods:The 3-week-old C57BL/6 male mice were injected with neuron-specific adeno-associated virus through stereotaxic brain after 7 days of normal environment adaptation.The mice were divided into normoxia group(AAV-NC-Nor),control hypoxia group(AAV-NC-Hyp),normal oxygen group with over-expression of postsynaptic density-95(PSD95)(AAV-PSD95-Nor),and hypoxia group with over-expression of PSD95(AAV-PSD95-Hyp).Using a hypobaric hypoxia chamber,PSD95-overexpressing mice were continuously ex-posed to hypoxic conditions for 14 days to establish a hypoxia exposure model.The open field,elevated cross maze and conditioned fear tests were used to detect the neurobehavioral activities of mice,and Golgi staining was used to observe the density of neuronal dendritic spines in cortex.The expression of PSD95,SYN1 and N-methyl-D-aspartate receptor subtype 2A(NMDAR2A)were detected by Western blot.Result:Compared with the normal oxygen group,the total distance and average speed of exercise in the open field experiment of mice in hypoxia group increased(P＜0.01),the rigidity time of mice in the conditioned fear box decreased(P＜0.01),and the density of dendritic spines in cortical region decreased(P＜0.05).The expressions of PSD95,SYN1 and NMDAR2A were decreased(P＜0.05).After the over-expression of PSD95,the autonomic activity of mice was reduced,the fear memory was relieved(P＜0.05),the dendrite density was reversed(P＜0.05),and the expression of synaptic related protein was increased(P＜0.05).Conclusion:Over-expression of PSD95 can alleviate neurobehavioral abnormalities and decline of fear memory induced under hypoxia exposure,protect neuronal dendritic spine injury in cortical region,and up-regulate the expression of syn-aptic protein.

The aim of this experiment was to study the effects of different feeding modes on growth performance,blood biochemical indexes and intestinal flora of lactating Holstein male calves.Twenty-four newborn Holstein male calves with body mass of(40.00±1.01)kg and similar day old were selected and randomly divided into four groups of six calves each.The subgroups were low-milk group(LM),high-milk group(HM),high-milk milk replacer feeding group(HMR),and low-milk switching to high-milk milk replacer feeding group(CMR).The results showed that:At 45 d,the body mass of calves in the HM group was significantly higher than that of calves in the other groups(P＜0.05),and at 60 d,the body mass of calves in the HM group was significantly higher than that of calves in the LM &.CMR groups(P＜0.05).At 90 d,the body mass of calves in the LM group was significantly higher than that of calves in the HM group.Throughout the ex-perimental period,the average daily weight gain and average pellet feed intake of calves in the LM group were significantly higher than that of calves in the HM group(P＜0.05).The calf globulin level in the HMR group was significantly higher than that in the LM and HM groups(P＜0.05);the plasma immunoglobulin A level of calves in the HM group was significantly lower than that of calves in the LM and HMR groups(P＜0.05);and the plasma immunoglobulin M level of calves in the HM group was significantly higher than that of calves in the LM and CMR groups(P＜0.05),and HMR group was also significantly higher than that of LM group(P＜0.05);plasma glutathione peroxidase level of calves in HMR group was significantly higher than that of LM group(P＜0.05);plasma malondialdehyde level of calves in LM group was significantly higher than that of calves in HMR and HM groups(P＜0.05),and CMR group was also significantly higher than that of HM group(P＜0.05).Relative abundance of Thermodesulfovibrio was higher in the HM group(P＜0.05),relative abundance of Bacteroidetes in the LM group was significantly higher than that in the HMR and HM groups(P＜0.05),relative abundance of Blautia in the HM group(P＜0.05),and relative abundance of Corynebacterium in the CMR group was significantly higher than that in the LM and HM groups(P＜0.05).In summary,calves in the LM group had better weaning weights and pellet feed intake;calves in the CMR group could compensate for growth by supplemental feeding of milk replacer to obtain more optimal weaning weights and pel-let feed intake;the HMR group proved that milk-free feeding could ensure stable growth of calves;and calves in the HM group had a better pre-lactation growth performance,lower levels of oxida-tive stress,and a healthier fecal flora.

Objective:To investigate the protective effect of PSD95 on neurobehavioral abnormalities and synaptic damage in cortex induced by hypoxia exposure in mice.Methods:The 3-week-old C57BL/6 male mice were injected with neuron-specific adeno-associated virus through stereotaxic brain after 7 days of normal environment adaptation.The mice were divided into normoxia group(AAV-NC-Nor),control hypoxia group(AAV-NC-Hyp),normal oxygen group with over-expression of postsynaptic density-95(PSD95)(AAV-PSD95-Nor),and hypoxia group with over-expression of PSD95(AAV-PSD95-Hyp).Using a hypobaric hypoxia chamber,PSD95-overexpressing mice were continuously ex-posed to hypoxic conditions for 14 days to establish a hypoxia exposure model.The open field,elevated cross maze and conditioned fear tests were used to detect the neurobehavioral activities of mice,and Golgi staining was used to observe the density of neuronal dendritic spines in cortex.The expression of PSD95,SYN1 and N-methyl-D-aspartate receptor subtype 2A(NMDAR2A)were detected by Western blot.Result:Compared with the normal oxygen group,the total distance and average speed of exercise in the open field experiment of mice in hypoxia group increased(P＜0.01),the rigidity time of mice in the conditioned fear box decreased(P＜0.01),and the density of dendritic spines in cortical region decreased(P＜0.05).The expressions of PSD95,SYN1 and NMDAR2A were decreased(P＜0.05).After the over-expression of PSD95,the autonomic activity of mice was reduced,the fear memory was relieved(P＜0.05),the dendrite density was reversed(P＜0.05),and the expression of synaptic related protein was increased(P＜0.05).Conclusion:Over-expression of PSD95 can alleviate neurobehavioral abnormalities and decline of fear memory induced under hypoxia exposure,protect neuronal dendritic spine injury in cortical region,and up-regulate the expression of syn-aptic protein.

Objective To explore the mechanism of Danggui Sini Decoction in treating knee osteoarthritis(KOA)by using network pharmacology,combined with in vitro experimental verification.Methods The active components of Danggui Sini Decoction were retrieved and screened through TCMSP,CNKI and PubMed databases,and their corresponding targets were predicted using the SwissTarget Prediction platform.KOA related targets were retrieved from GeneCards and OMIM databases.Intersection of drug targets and KOA targets was obtained,and key components,core targets,and their related biological mechanisms were identified through network topology analysis,GO and KEGG pathway enrichment analysis.Molecular docking was used to verify the degree of binding between key components and core targets.Danggui Sini Decoction containing serum was prepared,and an in vitro KOA model was constructed by inducing rat articular chondrocytes with lipopolysaccharide.The CCK-8 method was used to screen for the optimal concentration of drug containing serum intervention,fluorescent probes were used to detect intracellular ROS content,immunofluorescence was used to detect NF-κB p65 nuclear translocation,RT-qPCR was used to detect the expressions of IL-6,IL-1β and TNF-α mRNA,Western blot was used to detect the expression of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),NF-κB p65 and p-NF-κB p65 proteins.Results The results of network pharmacology analysis indicated that the treatment of KOA with Danggui Sini Decoction may involve regulating Toll like receptors,MAPK,TNF,apoptosis and other inflammatory and aging signaling pathways,compounds such as quercetin,kaempferol and glycyrrhizin may play important roles.Core targets included IL6,IL1B,TNF,TLR4,NFKB1,JUN,MAPK1,RELA.In vitro experiments showed that compared with the blank group,the ROS content in chondrocytes of the model group significantly increased(P<0.01),NF-κB p65 protein was significantly nuclear translocation(P<0.01),and mRNA expressions of IL-6,IL-1β,TNF-α mRNA and protein expressions of TLR4,MyD88 and p-NF-κB p65 significantly increased(P<0.01);compared with the model group,the intervention of Danggui Sini Decoction containing serum could significantly reduce intracellular ROS content(P<0.05),inhibit NF-κB p65 nuclear translocation(P<0.01),and reduce the expression of inflammatory factor mRNA and related proteins(P<0.05,P<0.01).Conclusion Danggui Sini Decoction can significantly reduce the inflammatory response of rat articular chondrocytes induced by lipopolysaccharide and exert therapeutic effects on KOA.Its mechanism may be related to the inhibition of TLR4/MyD88/NF-κB pathway.

Objective To investigate the effects of meridian and tendon acupuncture on the mitochondrial apoptosis of quadriceps femoris muscle cells in model rats of knee osteoarthritis(KOA);To explore its mechanism for the treatment of KOA.Methods Totally 40 SPF healthy male Wistar rats were randomly divided into sham-operation group(10 rats)and modeling group(30 rats).The modified Hulth method was used to establish a KOA rat model.The model rats were randomly divided into model group,celecoxib group and meridian and tendon acupuncture group,with 9 rats in each group.Corresponding intervention measures were given to each group for 14 consecutive days.Improved Lequesne MG score was used for evaluating knee joint function in rats,measuring thigh circumference,quadriceps femoris wet weight,wet weight maintenance rate and wet weight ratio of the affected limb,HE staining was used to observe the morphology of quadriceps femoris tissue,TUNEL method was used to detect apoptosis of quadriceps femoris cells,immunofluorescence was used to detect the expressions of reactive oxygen species(ROS),superoxide dismutase(SOD),Caspase-3 and Caspase-9 in quadriceps femoris muscle tissue,fluorescence double staining method was used to detect the co-expression of ROS and Caspase-3 in quadriceps femoris tissue,Western blot was used to detect the expressions of apoptosis related proteins in quadriceps femoris tissue.Results Compared with the sham-operation group,the improved Lequesne MG score of the knee joint in the model group rats increased(P<0.05),the circumference of the thigh,wet weight of the quadriceps femoris,wet weight maintenance rate and wet weight ratio of the affected limb decreased(P<0.05),the arrangement of quadriceps femoris muscle fibers was disordered and loose,with some muscle fibers dissolved and necrotic,accompanied by a large amount of inflammatory exudate,an increase in lymphocytes,and an increase in cell apoptosis index(P<0.05),the expressions of ROS,Caspase-3 and Caspase-9 in quadriceps femoris tissue increased,while the expression of SOD decreased(P<0.05),the protein expressions of Bcl-2,Bcl-XL,Bax,Cytochrome C(CytC),Caspase-3 and Caspase-9 in quadriceps femoris tissue increased(P<0.05).Compared with the model group,the improved Lequesne MG scores of the knee joint in the celecoxib group and the meridian and tendon acupuncture group decreased(P<0.05),while thigh circumference,quadriceps femoris wet weight,wet weight maintenance rate,wet weight ratio increased(P<0.05),the structure of quadriceps femoris muscle fibers was normal,the muscle membrane was relatively intact,the apoptosis index decreased(P<0.05),the expressions of ROS,Caspase-3 and Caspase-9 in quadriceps femoris tissue decreased,while the expression of SOD increased(P<0.05),the protein expressions of Bcl-2,Bcl-XL,Bax,CytC,Caspase-3 and Caspase-9 in quadriceps femoris muscle tissue decreased(P<0.05),and the expression trend of ROS and Caspase-3 in fluorescent double staining was consistent.Conclusion Meridian and tendon acupuncture can reduce ROS in the quadriceps femoris tissue of KOA model rats,inhibit the expressions of mitochondrial apoptosis-related proteins,thereby improving skeletal muscle strength,and play a certain therapeutic role.