BACKGROUND:Acupuncture is an effective method for lumbar pain in lumbar disc herniation,but its mechanism has not yet been clarified.Factors related to the JAK2/STAT3 signaling pathway regulate the body's inflammatory response and are involved in the process of neuropathic pain. OBJECTIVE:To study the mechanism of acupuncture on lumbar disc herniation in a rat model based on the JAK2/STAT3 signaling pathway. METHODS:Forty Sprague-Dawley rats were randomly divided into four groups:sham operation group,model group,acupuncture group,and acupuncture+agonist group,with 10 rats in each group.Animal models of L5 lumbar disc herniation was constructed through autologous disc cell transplantation in the model group,acupuncture group,and acupuncture+agonist group.Rats in the acupuncture group and the acupuncture+agonist group received acupuncture treatment(Yanglingquan,Shenshu,Huantiao,and Dachangshu acupoints)at 3 days after modeling,and acupuncture treatment was given once a day,20 minutes each,for 15 consecutive days.Rats in the acupuncture+agonist group were injected intrathecally with coumermycin A1,a JAK2 agonist,into the L4/L5 intervertebral space,once a day,20 minutes each,prior to the acupuncture at 6,12,and 18 days after modeling.Paw withdrawal mechanical threshold was detected before and 3,6,9,12,15,and 18 days after modeling.At 18 days after modeling,serum inflammatory factor levels were detected,hematoxylin-eosin staining was performed to observe the morphology of L5-L6 tissues,RT-PCR was performed to detect the expression of JAK2 and STAT3 mRNAs in L5-L6 tissues,and western blot was performed to detect the expression of JAK2,p-JAK2 and p-STAT3 proteins in L5-L6 tissues. RESULTS AND CONCLUSION:The paw withdrawal mechanical thresholds of rats in the model group at different time points after modeling were lower than those in the sham operation group(P<0.05),the paw withdrawal mechanical thresholds of rats in the acupuncture group were higher than those in the model group at 9,12,15,and 18 days after modeling(P<0.05),and the paw withdrawal mechanical thresholds of rats in the acupuncture+agonist group were lower than those in the acupuncture group at 9,12,15,and 18 days after modeling(P<0.05).The levels of interleukin 6,tumor necrosis factor α,neurotransmitter substance P,and brain neuropeptide Y were elevated in the model group compared with the sham operation group(P<0.05);the levels of all four inflammatory factors were reduced in the acupuncture group compared with the model group(P<0.05);and the levels of all four inflammatory factors were elevated in the acupuncture+agonist group compared with the acupuncture group(P<0.05).Hematoxylin-eosin staining showed that lumbar degeneration was obvious in the model group but reduced in the acupuncture group and the acupuncture+agonist group.Moreover,the reduction was more obvious in the acupuncture group compared with the acupuncture+agonist group.The JAK2 and STAT3 mRNA expression as well as the p-JAK2 and p-STAT3 protein expression were elevated in the model group compared with the sham operation group(P<0.05),were decreased in the acupuncture group compared with the model group(P<0.05),and were increased in the acupuncture+agonist group compared with the acupuncture group(P<0.05).To conclude,acupuncture can alleviate inflammation to exert analgesic effects in the rat model of lumbar disc herniation,and its mechanism of action may be related to the inhibition of the JAK2/STAT3 signaling pathway.

BACKGROUND:Immunosuppression leads to impaired body immune function and aggravates the disease.Herb-partitioned moxibustion can effectively regulate immune function and improve immunity in the body,but its regulatory mechanism has not been elucidated. OBJECTIVE:To sequence immunosuppressed model rats treated with herb-partitioned moxibustion using bioinformatics techniques based on transcriptomics and to explore the mechanisms by which it regulates immunity. METHODS:Twenty-four Sprague-Dawley rats were randomly assigned to three groups:control,model,and herb-partitioned moxibustion groups,with eight rats in each group.The model and herb-partitioned moxibustion groups were subjected to establishment of an immune suppression model by intraperitoneal injection of cyclophosphamide at a dose of 35 mg/kg for 3 consecutive days.No interventions were administered to the control and model groups after modeling.In contrast,the herb-partitioned moxibustion group received moxibustion treatment at Zhongwan,Shenque,Guanyuan,and Zusanli acupoints using a combination of moxa and herbal cakes,once a day,for 10 consecutive days,with samples being collected the day after the end of the intervention.Peripheral blood was collected from all groups of rats to measure their white blood cell count.RNA-seq was performed on the Illumina sequencing platform,and differentially expressed genes were selected for bioinformatics analysis using the GO and KEGG databases. RESULTS AND CONCLUSION:Compared with the control group,the model group exhibited a significant decrease in white blood cell count(P<0.001).RNA-seq analysis identified 3 026 differentially expressed genes between the model and control groups,with 1 565 upregulated and 1 461 downregulated.There were 535 differentially expressed genes identified between the herb-partitioned moxibustion group and the model group,with 280 upregulated and 255 downregulated.The Venn diagram analysis revealed that 159 genes were downregulated in the model group compared with the control group.However,after moxibustion with herbal cakes,these genes were upregulated.Protein-protein interaction network analysis identified 10 core targets,including Oasl,Oas2,Isg15,Herc6,Mx2,Helz2,Mx1,Syk,Hspa1a,and Ret.According to GO and KEGG analyses,moxibustion with herbal cakes regulated the body through pathways related to immune response,viruses,angiogenesis,and the autoimmune system.To conclude,there is a significant association between herbal cake-separated moxibustion intervention and immune suppression targets,including Oasl,Oas2,Isg15,Herc6,Mx2,Helz2,and Mx1.The intervention exhibits regulatory effects in the pathways related to immune responses,viral activities,and angiogenesis.

BACKGROUND:Stroboscopic visual training can force sensory reweighting to restore the original weights by increasing sensitivity to proprioceptive information,which may be an effective method to improve proprioception. OBJECTIVE:To determine the effects of balance training in three conditions,low frequency,high frequency and normal vision,on ankle proprioception in patients with chronic ankle instability. METHODS:Thirty-six patients with chronic ankle instability recruited from the students of Southwest Medical University were randomly assigned to a low-frequency vision training group,a high-frequency vision training group,and a normal vision training group,with 12 subjects in each group.Subjects in the three groups underwent progressive hop stabilization and balance training,in which the low-frequency vision training group and the high-frequency vision training group wore stroboscopic spectacles during the training,with a stroboscopic frequency of 1.75 and 5 Hz,respectively.The training in each group was performed three times a week for 4 consecutive weeks.Assessments,including ankle proprioception,ankle stability self-assessment and dynamic postural stability,were performed before training and within 1 week after the completion of training. RESULTS AND CONCLUSION:There was a significant main effect of time factor in ankle proprioception(P<0.05).Compared with the pre-training period,subjects in the low-frequency vision training group and the high-frequency vision training group showed significant improvement in ankle proprioception after 4 weeks of training(P<0.05);and subjects in the low-frequency vision training group showed a significant improvement in ankle proprioception compared with that of the normal vision training group after 4 weeks of training(P<0.05).There were significant main effects of time factor and group×time interaction in ankle proprioception(P<0.05).Compared with the pre-training period,the ankle stability self-assessment in all three groups was improved after 4 weeks of training(P<0.05).And the ankle stability self-assessment in high-frequency visual training group was higher than that in normal vision training group after 4 weeks of training(P<0.05).Compared with the pre-training period,subjects in the low-frequency vision training group and the high-frequency vision training group showed significant improvements in forward dynamic postural stability,posteromedial dynamic postural stability,and posterolateral dynamic postural stability after 4 weeks of training(P<0.05),while in the normal vision training group,forward dynamic postural stability and posterolateral dynamic postural stability were significantly improved after 4 weeks of training(P≤0.05).To conclude,balance training under stroboscopic visual conditioning improves proprioception,ankle stability self-assessment,and dynamic postural stability in patients with chronic ankle instability regardless of frequency.

BACKGROUND:Fibromyalgia syndrome,as a common rheumatic disease,is related to central sensitization and immune abnormalities.However,the specific mechanism has not been elucidated,and there is a lack of specific diagnostic markers.Exploring the possible pathogenesis of this disease has important clinical significance. OBJECTIVE:To screen the potential diagnostic marker genes of fibromyalgia syndrome and analyze the possible immune infiltration characteristics based on bioinformatics methods,such as weighted gene co-expression network analysis(WGCNA),and machine learning. METHODS:Gene expression profiles in peripheral serum of fibromyalgia syndrome patients and healthy controls were obtained from the gene expression omnibus(GEO)database.The differentially co-expressed genes were screened in the expression profile by differential analysis and WGCNA analysis.Least absolute shrinkage and selection operator(LASSO)and support vector machine-recursive feature elimination(SVM-RFE)machine learning algorithm were further used to identify hub biomarkers,and draw receiver operating characteristic curve(ROC)to evaluate the accuracy of diagnosing fibromyalgia syndrome.Finally,single sample gene set enrichment analysis(ssGSEA)and gene set enrichment analysis(GSEA)were used to evaluate the immune cell infiltration and pathway enrichment in patients with fibromyalgia syndrome. RESULTS AND CONCLUSION:Eight down-regulated differentially expressed genes(DEGs)were obtained after differential analysis of the GSE67311 dataset according to the conditions of log2|(FC)|>0 and P<0.05.After WGCNA analysis,497 genes were included in the module(MEdarkviolet)with the highest positive correlation(r=0.22,P=0.04),and 19 genes were included in the module(MEsalmon2)with the highest negative correlation(r=-0.41,P=6×10-5).After intersecting DEGs and the module genes of WGCNA,seven genes were obtained.Four genes were screened out by LASSO regression algorithm and five genes were screened out by SVM-RFE machine learning algorithm.After the intersection of the two,three core genes were identified,which were germinal center associated signaling and motility like,integrin beta-8,and carboxypeptidase A3.The areas under the ROC curve of the three core genes were 0.744,0.739,and 0.734,respectively,indicating that they have good diagnostic value and can be used as biomarkers for fibromyalgia syndrome.The results of immune infiltration analysis showed that memory B cells,CD56 bright NK cells,and mast cells were significantly down-regulated in patients with fibromyalgia syndrome compared with the control group(P<0.05),and were significantly positively correlated with the above three biomarkers(P<0.05).The enrichment analysis suggested that there were nine fibromyalgia syndrome enrichment pathways,mainly related to olfactory transduction pathway,neuroactive ligand-receptor interaction,and infection pathway.The above results showed that the occurrence and development of fibromyalgia syndrome are related to the involvement of multiple genes,abnormal immune regulation,and multiple pathways imbalance.However,the interactions between these genes and immune cells,as well as their relationships with various pathways need to be further investigated.

BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

BACKGROUND:Macrophage migration inhibitory factor(MIF)is a pleiotropic cytokine,which is secreted in different types of stem cells and can regulate the proliferation,differentiation and migration of various types of stem cells.Our previous research has confirmed that human embryonic stem cells secrete MIF and that its concentration in the culture medium is relatively stable.However,whether MIF is involved in the survival,proliferation and differentiation of human embryonic stem cells remains unclear. OBJECTIVE:To investigate the effects of MIF on survival,proliferation,and differentiation of human embryonic stem cells. METHODS:(1)Human embryonic stem cells H9 were cultured.The growth curve of cells was detected and plotted by CCK-8 assay.Enzyme-linked immunosorbent assay was used to determine the level of MIF in the medium.(2)To determine the effects of exogenous MIF on the survival and proliferation of human embryonic stem cells,different groups were established:the control group,which was cultured in stem cell medium without any modifications;the exogenous MIF group,which was treated with different concentrations(30,100,300 ng/mL)of MIF in the stem cell medium;the MIF inhibitor ISO-1 group,which was treated with different concentrations(2,7,21 μmol/L)of ISO-1 in the stem cell medium;and the MIF+ISO-1 group,which was treated with different concentrations of ISO-1 along with 100 ng/mL of MIF.Cell viability was assessed using the CCK-8 assay.(3)To further elucidate the effect of MIF gene on survival and proliferation of human embryonic stem cell,the MIF knockout H9 cell line was constructed by CRISPR-Cas 9 technology to observe the lineage establishment.(4)To determine the effect of high concentrations of MIF on human embryonic stem cell differentiation,100 ng/mL MIF and 100 ng/mL of CXCR4 neutralizing antibody were separately added to the normal stem cell culture medium.The expression levels of self-renewal factors(KLF4,c-MYC,NANOG,OCT4,and SOX2)and differentiation transcription factors(FOXA2,OTX2)were measured using real-time quantitative polymerase chain reaction,immunofluorescence staining,and western blot analysis. RESULTS AND CONCLUSION:(1)The logarithmic growth phase of H9 cells was between 3-6 days.Under normal growth conditions,human embryonic stem cells secreted MIF at a concentration of approximately 20 ng/mL,independent of cell quantity.(2)Compared to the control group,the addition of different concentrations of MIF had no effect on the proliferation of human embryonic stem cells(P>0.05).ISO-1 significantly inhibited the proliferation of human embryonic stem cells,with a stronger inhibition observed at higher concentrations of ISO-1(P<0.05).The addition of MIF in the presence of ISO-1 reduced the inhibitory effect of ISO-1(P<0.05).(3)Real-time quantitative polymerase chain reaction showed that knocking out 50%of the MIF gene resulted in a significant decrease in the growth vitality of human embryonic stem cells and failure to establish cell lines.(4)Adding 100 ng/mL exogenous MIF to the culture medium resulted in a decrease in the mRNA,protein,and fluorescence expression levels of the self-renewal transcription factor KLF4,while the mRNA,protein,and fluorescence expression levels of the differentiation factor FOXA2 increased.(5)When 100 ng/mL CXCR4 neutralizing antibody was added to the culture medium,the mRNA and protein expression levels of KLF4 increased,while the mRNA and protein expression levels of FOXA2 decreased,contrary to the expression trend observed in the MIF group.In conclusion,the endogenous secretion of MIF by human embryonic stem cells is essential for their survival.The addition of MIF to the culture medium does not promote the proliferation of human embryonic stem cells.However,it can lead to a decrease in the expression of the self-renewal factor KLF4 and an increase in the expression of the transcription factor FOXA2.This provides a clue for further investigation into the effects and mechanisms of MIF on the differentiation of human embryonic stem cells.The MIF-CXCR4 axis plays a regulatory role in this process.

BACKGROUND:Endometrial receptivity is a key factor in embryo implantation in northwest Tibetan cashmere goats,and the expression of genes related to endometrial receptivity and their variable splicing are still unclear. OBJECTIVE:To analyze and explore genes and variable splicing events related to endometrial receptivity in northwest Tibetan cashmere goats. METHODS:On days 5 and 15 of pregnancy(representing pre receptive endometrium group and receptive endometrium group),three northwest Tibetan cashmere goats were randomly selected.Endometrial tissue was collected and stained with hematoxylin and eosin to observe tissue morphology.Immunohistochemical staining was used to detect the expression of endometrial receptive marker proteins leukemia inhibitory factor and vascular endothelial growth factor.After the total RNA was extracted and the quality test was qualified,transcriptome sequencing was performed to search differentially expressed mRNAs,lncRNAs,circRNAs,and miRNAs,perform functional prediction,and analyze alternative splicing mRNAs and lncRNAs related to endometrial receptivity. RESULTS AND CONCLUSION:(1)Compared with the pre receptive endometrium group,the expression levels of leukemia inhibitory factor and vascular endothelial growth factor proteins in the endometrial tissue of the receptive endometrium group were significantly increased.(2)The sequencing results showed that the differentially expressed genes were mostly mRNA and lncRNA genes,including 250 upregulated mRNAs,193 upregulated lncRNAs,135 downregulated mRNAs,and 123 downregulated lncRNAs,which were significantly enriched in the Wnt,Hedgehog,and Hippo signaling pathways.(3)Alternative splicing event analysis uncovered 8 differentially expressed variable splicing transcripts,which were all mRNA transcripts,including 2 downregulated and 6 upregulated,and were significantly associated with vascular endothelial growth factor receptor signaling,cell motility,and embryonic development.

BACKGROUND:Previous studies have found that neohesperidin can delay bone loss in ovariectomized mice and has the potential to treat osteoporosis,but its specific mechanism of action remains to be explored. OBJECTIVE:To explore the key targets and possible mechanisms of neohesperidin in the treatment of osteoporosis based on bioinformatics and cell experiments in vitro. METHODS:The gene expression dataset related to osteoporosis was obtained from GEO database,and the differentially expressed genes were screened and analyzed in R language.The osteoporosis-related targets were screened from GeneCards and DisGeNET databases,and the neohesperidin-related targets were screened from ChEMBL and PubChem databases,and the common targets were obtained by intersection of the three.The String database was used to construct the PPI network of intersection genes,and the key targets were screened.The DAVID database was used for GO and KEGG enrichment analysis.The AutoDock software was used to verify the molecular docking between the neohesperidin and the target protein.The effect of neohesperidin on osteogenic differentiation of C57 mouse bone marrow mesenchymal stem cells was detected.Complete medium was used as blank control group;osteogenic induction medium was used as the control group;and osteogenic induction medium containing different concentrations of neohesperidin(25,50 μmol/L)was used as experimental group.The expression of alkaline phosphatase,the degree of mineralization,the expression of osteogenic-related genes and target genes during osteogenic differentiation of cells were measured at corresponding time points. RESULTS AND CONCLUSION:(1)9 253 differentially expressed genes,2 161 osteoporosis-related targets,and 326 neohesperidin-related targets were screened.There were 53 common targets among the three.All 53 genes were up-regulated in osteoporosis samples.The PPI network screened the target gene PRKACA of research significance.GO function and KEGG pathway enrichment analysis showed that neohesperidin's treatment of osteoporosis through PRKACA target mainly depended on biological processes such as protein phosphorylation and protein autophosphorylation,acting on endocrine resistance,proteoglycan in cancer,and estrogen signaling pathway to play a therapeutic role.Molecular docking results showed that neohesperidin had a certain binding ability to the protein corresponding to the target PRKACA.(2)The results of alkaline phosphatase staining showed that neohesperidin could promote the expression of alkaline phosphatase in the early stage of osteogenic differentiation of mesenchymal stem cells.Alizarin red staining showed that neohesperidin could promote the mineralization of osteogenic differentiation of mesenchymal stem cells.RT-qPCR results showed that neohesperidin could increase the mRNA expression of alkaline phosphatase,PRKACA,and osteocalcin.(3)These results indicate that neohesperidin may promote osteogenic differentiation through PRKACA target on the estrogen signaling pathway to prevent and treat osteoporosis.

BACKGROUND:Lijin manipulation can promote skeletal muscle repair and treat skeletal muscle injury.However,the formation of fibrosis and scar tissue hyperplasia are closely related to the quality of skeletal muscle repair.To study the regulatory effect of Lijin manipulation on the formation of fibrosis and scar tissue hyperplasia is helpful to explain the related mechanism of Lijin manipulation to improve the repair quality of skeletal muscle injury. OBJECTIVE:To explore the mechanism of Lijin manipulation to improve the repair quality of skeletal muscle injury in rabbits,thereby providing a scientific basis for clinical treatment. METHODS:Forty-five healthy adult Japanese large-ear white rabbits were randomly divided into blank group,model group and Lijin group,with 15 rats in each group.Gastrocnemius strike modeling was performed in both model group and Lijin group.The Lijin group began to intervene with tendon manipulation on the 3rd day after modeling,once a day,and 15 minutes at a time.Five animals in each group were killed on the 7th,14th and 21st days after modeling.The morphology and inflammatory cell count of gastrocnemius were observed by hematoxylin-eosin staining,the collagen fiber amount was observed by Masson staining,the expression of interleukin-6 and interleukin-10 in gastrocnemius was detected by ELISA.The protein and mRNA expressions of paired cassette gene 7,myogenic differentiation factor,myoblastogenin,alpha-actin,transforming growth factor beta 1,and type Ⅰ collagen were detected by western blot and RT-PCR,respectively,and the expression of type Ⅰ collagen protein was detected by immunohistochemistry. RESULTS AND CONCLUSION:Hematoxylin-eosin staining and Masson staining showed that compared with the model group,inflammatory cell infiltration and collagen fiber content decreased in the Lijin group(P<0.01),and the muscle fibers gradually healed.ELISA results showed that compared with the model group,the expression of interleukin-6 in the Lijin group continued to decrease(P<0.05),and the expression of interleukin-10 increased on the 7th day after modeling(P<0.05)and then showed a decreasing trend(P<0.05).Western blot and RT-PCR results showed that compared with the model group,the protein and mRNA expressions of paired cassette gene 7,myogenic differentiation factor,myoblastogenin in the Lijin group were significantly increased on the 14th day after modeling(P<0.05),but decreased on the 21st day(P<0.05);the protein and mRNA expressions of alpha-actin,transforming growth factor beta 1,and type Ⅰ collagen in the Lijin group were significantly decreased compared with those in the model group(P<0.05).Immunohistochemical results showed that the expression of type Ⅰ collagen in the Lijin group was significantly lower than that in the model group(P<0.05).To conclude,Lijin manipulation could improve the repair quality of skeletal muscle injury by inhibiting inflammation,promoting the proliferation and differentiation of muscle satellite cells,and reducing fibrosis.

BACKGROUND:Changes in skeletal muscle mass have been indicated in studies addressing the effects of low-frequency pulsed magnetic fields on the structure and morphology of the skeletal muscle,but no relevant studies have been conducted on the morphologic changes that occur after chronic exposure to the low-frequency pulsed magnetic field. OBJECTIVE:To observe the effects of chronic exposure to low-frequency pulsed magnetic fields on the maximal voluntary contraction and morphologic indicators of the quadriceps muscle of the leg,thereby providing a reference of muscle morphologic changes for the use of this technique as a strategy for muscle function improvement. METHODS:Seventy healthy subjects were recruited and randomly divided into a test group that received magnetic field stimulation and a control group that underwent sham treatment,with 35 subjects in each group,and the total duration of the trial was 4 weeks.The test group underwent low-frequency pulsed magnetic stimulation for 15 minutes every 48 hours,while the control group underwent sham treatment,with the same intervention interval and duration as the test group.After 4 weeks of intervention,changes in the maximum voluntary contraction value of the quadriceps muscle in different groups were observed,and B-mode ultrasonography was utilized as a means of assessment to observe changes in muscle thickness,muscle cross-sectional area,and pinnation angle indexes. RESULTS AND CONCLUSION:After 4 weeks of chronic exposure to low-frequency pulsed magnetic fields,68 subjects completed the test.The maximum voluntary contraction value of the quadriceps muscle in the test group increased significantly(P=0.000),and the increment was significantly higher than that of the control group(P=0.008).Three indexes related to muscle morphology in the test group were significantly higher than the pre-test values(P=0.000),while in the control group,muscle thickness showed a significant reduction(P=0.020),there was no significant change in the pinnation angle,but a significant increase in the cross-sectional area(P=0.000).Intergroup comparisons revealed that the three indicators related to muscle morphology,including muscle thickness(P=0.012),pinnation angle(P=0.003),and cross-sectional area(P=0.049),were significantly higher in the test group than in the control group.The above data confirmed that the maximum voluntary contraction of the quadriceps muscle was significantly increased in healthy adults after 4 weeks of chronic exposure to the low-frequency pulsed magnetic field,and significant increases in the three muscle morphometric indices of muscle thickness,cross-sectional area,and pinnation angle were observed in the test group,providing a basis of muscle tissue morphology for the use of this technique as an exercise alternative and medical treatment strategy for muscle improvement.