1.The pathological progression of steroid-induced osteonecrosis of the femoral head caused by oxidative stress-induced osteoblast ferroptosis
Jiahao ZHANG ; Yuhao LIU ; Chi ZHOU ; Liang MO ; Hanjun FANG ; Zhenqiu CHEN
Chinese Journal of Tissue Engineering Research 2024;28(20):3202-3208
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.
2.A deep transfer learning method using plain radiographs for the differential diagnosis of osteonecrosis of the femoral head with other hip diseases
Zeqing HUANG ; Yuhao LIU ; Hanjun FANG ; Haicheng CHEN ; Haibin WANG ; Zhenqiu CHEN ; Chi ZHOU
Chinese Journal of Orthopaedics 2023;43(1):72-80
Objective:To develop a deep transfer learning method for the differential diagnosis of osteonecrosis of the femoral head (ONFH) with other common hip diseases using anteroposterior hip radiographs.Methods:Patients suffering from ONFH, DDH, and other hip diseases including primary hip osteoarthritis, non-infectious inflammatory hip disease, and femoral neck fracture treated in the First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2018 to December 2020 were enrolled in the study. A clinical data set containing anteroposterior hip radiographs of the eligible patients was created. Data augmentation by rotating and flipping images was performed to enlarge the data set, then the data set was divided equally into a training data set and a testing data set. The ResNet-152, a deep neural network model, was used in the study, but the original Batch Normalization was replaced with Transferable Normalization to construct a novel deep transfer learning model. The model was trained to distinguish ONFH and DDH from other common hip diseases using anteroposterior hip radiographs on the training data set and its classification performance was evaluated on the testing data set.Results:The clinical data set was comprised of anteroposterior hip radiographs of 1024 hips, including 542 with ONFH, 296 with DDH, and 186 with other common hip diseases (56 hips with primary osteoarthritis, 85 hips with non-infectious inflammatory osteoarthritis, 45 hips with femoral neck fracture). After data augmentation, the size of the data set multiplied to 6144. The model was trained 100 050 times in each task. Accuracy was used as the representative parameter to evaluate the performance of the model. In the binary classification task to identify ONFH, the best accuracy was 95.80%. As for the multi-classification task for classification of ONFH and DDH from other hip diseases, the best accuracy was 91.40%. The plateau of the model was observed in each task after 50 000 times of training. The mean accuracy in plateaus was 95.35% (95% CI: 95.33%, 95.37%), and 90.85% (95% CI: 90.82%, 90.87%), respectively. Conclusion:The present study proves the encouraging performance of a deep transfer learning method for the first-visit classification of ONFH, DDH, and other hip diseases using the convenient and economical anteroposterior hip radiographs.
3.Urolithin A mediates p38/MAPK pathway to inhibit osteoclast activity
Haoran HUANG ; Yinuo FAN ; Wenxiang WEI-YANG ; Mengyu JIANG ; Hanjun FANG ; Haibin WANG ; Zhenqiu CHEN ; Yuhao LIU ; Chi ZHOU
Chinese Journal of Tissue Engineering Research 2024;28(8):1149-1154
BACKGROUND:Overactive osteoclasts disrupt bone homeostasis and play a bad role in the pathological mechanisms of related skeletal diseases,such as osteoporosis,fragility fractures,and osteoarthritis.Studies have confirmed that ellagic acid and ellagtannin have the potential to inhibit osteoclast differentiation.As their natural metabolites,urolithin A has antioxidant,anti-inflammatory,anti-proliferative and anti-cancer effects,but its effect on osteoclast differentiation and its underlying molecular mechanisms remain unclear. OBJECTIVE:To explore the effect of urolithin A on osteoclast differentiation induced by receptor activator for nuclear factor-κB ligand and its mechanism. METHODS:Mouse mononuclear macrophage leukemia cells(RAW264.7)that grew stably were cultured in vitro.Toxicity of urolithin A(0,0.1,0.5,1.5,2.5 μmol/L)to RAW264.7 cells were detected by cytotoxic MTS assay to screen out the safe concentration.Different concentrations of urolithin A were used again to intervene with receptor activator for nuclear factor-κB ligand-induced differentiation of RAW264.7 cells in vitro.Then,tartrate-resistant acid phosphatase staining and F-actin ring and nucleus staining were performed to observe its effect on the formation and function of osteoclasts.Finally,the expressions of urolithin A on upstream and downstream genes and proteins in the MAPK signaling pathway were observed by western blot and RT-qPCR assays. RESULTS AND CONCLUSION:Urolithin A inhibited osteoclast differentiation and F-actin ring formation in a concentration-dependent manner and 2.5 μmol/L had the strongest inhibitory effect.Urolithin A inhibited the mRNA expression of Nfatc1,Ctsk,Mmp9 and Atp6v0d2 and the protein synthesis of Nfatc1 and Ctsk,related to osteoclast formation and bone resorption.Urolithin A inhibited the activity of osteoclasts by downregulating the phosphorylation of p38 protein to inhibit the mitogen-activated protein kinase signaling pathway.
4.Influencing factors of liver regeneration after full-size split liver transplantation
Yuhao DU ; Yuying SHAN ; Shuqi MAO ; Changjiang LU ; Shengdong WU ; Jing HUANG ; Jiongze FANG ; Caide LU
Chinese Journal of General Surgery 2024;39(9):692-697
Objective:To investigate the factors influencing recipient liver regeneration after full-size split liver transplantation (fSLT).Methods:The clinical data of patients undergoing split liver transplantation in the Affiliated Li Huili Hospital of Ningbo University from May 2019 to Sep 2023 were retrospectively collected. Graft volume (GV) and initial graft volume (IGV) at (30±7) days after operation were measured, and postoperative liver regeneration rate (LRR) was calculated. The patients undergoing fSLT were divided into high regeneration group and low regeneration group with LRR=30% as boundary. The differences of donor and recipient data and perioperative data between the two groups were compared.Results:A total of 52 patients were included. The low fSLT regeneration group (16 cases) was compared with the high fSLT regeneration group (36 cases), and in high fSLT regeneration group donor age was lower, the donor liver steatosis was less, GRWR was lower, the incidence of hepatitis B virus-related liver disease was lower, the postoperative diagnosis of malignant liver disease was lower, the intraoperative blood loss was less, and the postoperative platelet count was higher. The levels of liver enzyme and total bilirubin (TBiL) were higher than those in high regeneration group ( P<0.05). Conclusions:Donor age, donor liver steatosis, GRWR, hepatitis B virus associated liver disease, and recipient pathogenesis are important factors affecting liver regeneration after fSLT. Postoperative platelet and liver enzyme levels are important indicators for monitoring liver regeneration after fSLT.
5.The mechanism of OC-STAMP overexpression induced actin cytoskeleton remodeling in promoting epithelial-mesenchymal transition in the alveolar type Ⅱ epithelial cell
Fei GENG ; Yuhao CAI ; Ying ZHAO ; Zhongqiu WEI ; Hong XU ; Fang YANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2023;41(11):801-807
Objective:To explore the mechanism of osteoclast stimulatory transmembrane protein (OC-STAMP) overexpression on epithelial-mesenchymal transition (EMT) .Methods:In April 2021, mice alveolar type Ⅱ epithelial cells MLE-12 were divided into five groups: overexpression control group (NC group), Ocstamp overexpression group (over- Ocstamp group), Fasudil intervention group (over- Ocstamp+Fasudil group), silence control group (si-NC group), Ocstamp silence group (si- Ocstamp group). The protein expressions of OC-STAMP, epithelial marker protein-E-cadherin (E-cad), interstitial marker protein-α-smooth muscle actin (α-SMA), Ras homolog gene family member A (RhoA), Rho GDP dissociation inhibitor α (Rho GDIα), Rho-associated protein kinase (ROCK), phosphate myosin phosphatase (p-MYPT) were examined by Western blotting and Immunocytochemical staining. The filamentous actin (F-actin) was detected by Phalloidin method. t test was used to compare the relative expression of each protein between the two groups. Results:Western blotting and Immunocytochemical staining showed that compared with the NC group, the expression level of E-cad was down-regulated, while the expression levels of α-SMA, Rho GDIα, RhoA, ROCK, p-MYPT were increased, and F-actin expression was enhanced in the over- Ocstamp group. The differences were statistically significant ( P<0.05). There were no significant differences in E-cad and α-SMA protein expression in si- Ocstamp group compared with si-NC group ( P>0.05). Compared with over- Ocstamp group, the expression level of E-cad protein in over- Ocstamp+Fasudil group was up-regulated, the expression levels of α-SMA, Rho GDIα, RhoA, ROCK and p-MYPT protein were decreased, and F-actin expression was weakened, with statistical significance ( P<0.05) . Conclusion:OC-STAMP overexpression in alveolar type Ⅱ epithelial cells may induce actin cytoskeleton remodeling through activation of Rho GDIα/RhoA/ROCK signaling pathway, thus promoting EMT.
6.The mechanism of OC-STAMP overexpression induced actin cytoskeleton remodeling in promoting epithelial-mesenchymal transition in the alveolar type Ⅱ epithelial cell
Fei GENG ; Yuhao CAI ; Ying ZHAO ; Zhongqiu WEI ; Hong XU ; Fang YANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2023;41(11):801-807
Objective:To explore the mechanism of osteoclast stimulatory transmembrane protein (OC-STAMP) overexpression on epithelial-mesenchymal transition (EMT) .Methods:In April 2021, mice alveolar type Ⅱ epithelial cells MLE-12 were divided into five groups: overexpression control group (NC group), Ocstamp overexpression group (over- Ocstamp group), Fasudil intervention group (over- Ocstamp+Fasudil group), silence control group (si-NC group), Ocstamp silence group (si- Ocstamp group). The protein expressions of OC-STAMP, epithelial marker protein-E-cadherin (E-cad), interstitial marker protein-α-smooth muscle actin (α-SMA), Ras homolog gene family member A (RhoA), Rho GDP dissociation inhibitor α (Rho GDIα), Rho-associated protein kinase (ROCK), phosphate myosin phosphatase (p-MYPT) were examined by Western blotting and Immunocytochemical staining. The filamentous actin (F-actin) was detected by Phalloidin method. t test was used to compare the relative expression of each protein between the two groups. Results:Western blotting and Immunocytochemical staining showed that compared with the NC group, the expression level of E-cad was down-regulated, while the expression levels of α-SMA, Rho GDIα, RhoA, ROCK, p-MYPT were increased, and F-actin expression was enhanced in the over- Ocstamp group. The differences were statistically significant ( P<0.05). There were no significant differences in E-cad and α-SMA protein expression in si- Ocstamp group compared with si-NC group ( P>0.05). Compared with over- Ocstamp group, the expression level of E-cad protein in over- Ocstamp+Fasudil group was up-regulated, the expression levels of α-SMA, Rho GDIα, RhoA, ROCK and p-MYPT protein were decreased, and F-actin expression was weakened, with statistical significance ( P<0.05) . Conclusion:OC-STAMP overexpression in alveolar type Ⅱ epithelial cells may induce actin cytoskeleton remodeling through activation of Rho GDIα/RhoA/ROCK signaling pathway, thus promoting EMT.
7.A multicenter study to test the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of clinical application
Xian LI ; Jia ZHENG ; Shibo WEI ; Hangyu LI ; Lei JIANG ; Lei DONG ; Jiang WANG ; Chongzhu TAO ; Yuhao YAN ; Lihui SUN ; Lunbo CUI ; Jinhai HUANG ; Yuxuan FANG ; Chengxin TANG
Chinese Journal of Surgery 2023;61(12):1080-1085
Objectives:To verify the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of its clinical application.Methods:A convenience sampling method was used to collect 129 geriatric patients who underwent inguinal hernia surgery from January 2018 to January 2023 in nine hospitals in Liaoning Province. There were 120 males and 9 females, of whom 89 patients were 60 to <75 years old, 33 patients were 75 to <85 years old and 7 patients were ≥85 years old. The 129 patients included 11 elderly patients with inguinal hernia who had recovered from preoperative infection with COVID-19. Statistical methods such as Cronbach′s coefficient, Kaiser-Meyer-Olkin test, Bartlett′s test, Pearson′s correlation analysis, etc. were calculated to verify the reliability indexes such as feasibility, content validity, structural validity, criterion-related validity, internal consistency reliability, and re-test reliability. Taking the 5-item modified frailty index (5-mFI) as the gold standard, the area under the curve was used to analyze the ability of the two scales to predict the occurrence of postoperative acute urinary retention, postoperative delirium, poor incision healing, operative hematoma seroma, and postoperative complications.Results:The frailty assessment scale for elderly patients with inguinal hernia showed good reliability and validity (valid completion rate of 99.2%; item content validity index of 1.000, and the scale content validity index of 1.000; exploratory factor analysis extracted a total of 1 principal component, and factor loadings of each item of 0.565 to 0.873; the AUC for frailty diagnosis using 5-mFI as the gold standard of 0.795 ( P<0.01) Cronbach′s coefficient of 0.916, retest reliability coefficient of 0.926), it could effectively predict postoperative acute urinary retention, delirium, hematoma seroma in the operative area and total complications (AUC of 0.746, 0.870, 0.806, and 0.738, respectively; all P<0.05), and prediction efficiency was higher than that of 5-mFI (AUC of 0.694, 0.838, 0.626 and 0.641, P<0.05 for delirium only), but both scales were inaccurate in predicting poor incision healing (AUC of 0.519, P=0.913 for the frailty assessment scale and 0.455, P=0.791 for the 5-mFI). Conclusions:The frailty assessment scale for elderly patients with inguinal hernia is reliable and significantly predicts the occurrence of postoperative adverse events in elderly inguinal hernia patients. The scale can also be used for preoperative frailty assessment in elderly patients with inguinal hernia after rehabilitation from COVID-19 infection.
8.A multicenter study to test the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of clinical application
Xian LI ; Jia ZHENG ; Shibo WEI ; Hangyu LI ; Lei JIANG ; Lei DONG ; Jiang WANG ; Chongzhu TAO ; Yuhao YAN ; Lihui SUN ; Lunbo CUI ; Jinhai HUANG ; Yuxuan FANG ; Chengxin TANG
Chinese Journal of Surgery 2023;61(12):1080-1085
Objectives:To verify the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of its clinical application.Methods:A convenience sampling method was used to collect 129 geriatric patients who underwent inguinal hernia surgery from January 2018 to January 2023 in nine hospitals in Liaoning Province. There were 120 males and 9 females, of whom 89 patients were 60 to <75 years old, 33 patients were 75 to <85 years old and 7 patients were ≥85 years old. The 129 patients included 11 elderly patients with inguinal hernia who had recovered from preoperative infection with COVID-19. Statistical methods such as Cronbach′s coefficient, Kaiser-Meyer-Olkin test, Bartlett′s test, Pearson′s correlation analysis, etc. were calculated to verify the reliability indexes such as feasibility, content validity, structural validity, criterion-related validity, internal consistency reliability, and re-test reliability. Taking the 5-item modified frailty index (5-mFI) as the gold standard, the area under the curve was used to analyze the ability of the two scales to predict the occurrence of postoperative acute urinary retention, postoperative delirium, poor incision healing, operative hematoma seroma, and postoperative complications.Results:The frailty assessment scale for elderly patients with inguinal hernia showed good reliability and validity (valid completion rate of 99.2%; item content validity index of 1.000, and the scale content validity index of 1.000; exploratory factor analysis extracted a total of 1 principal component, and factor loadings of each item of 0.565 to 0.873; the AUC for frailty diagnosis using 5-mFI as the gold standard of 0.795 ( P<0.01) Cronbach′s coefficient of 0.916, retest reliability coefficient of 0.926), it could effectively predict postoperative acute urinary retention, delirium, hematoma seroma in the operative area and total complications (AUC of 0.746, 0.870, 0.806, and 0.738, respectively; all P<0.05), and prediction efficiency was higher than that of 5-mFI (AUC of 0.694, 0.838, 0.626 and 0.641, P<0.05 for delirium only), but both scales were inaccurate in predicting poor incision healing (AUC of 0.519, P=0.913 for the frailty assessment scale and 0.455, P=0.791 for the 5-mFI). Conclusions:The frailty assessment scale for elderly patients with inguinal hernia is reliable and significantly predicts the occurrence of postoperative adverse events in elderly inguinal hernia patients. The scale can also be used for preoperative frailty assessment in elderly patients with inguinal hernia after rehabilitation from COVID-19 infection.
9.cGAS/STING signaling pathways induces the secretion of type Ⅰ interferon in porcine alveolar macrophages infected with porcine circovirus type 2.
Hongbo CHEN ; Feng LI ; Wenyan LAI ; Yuhao FANG ; Mingyong JIANG ; Dianning DUAN ; Xiaoyan YANG
Chinese Journal of Biotechnology 2021;37(9):3201-3210
In order to study the signal pathway secreting type Ⅰ interferon in porcine alveolar macrophages (PAMs) infected with porcine circovirus type 2 (PCV2), the protein and the mRNA expression levels of cGAS/STING pathways were analyzed by ELISA, Western blotting and quantitative reverse transcriptase PCR in PAMs infected with PCV2. In addition, the roles of cGAS, STING, TBK1 and NF-κB/P65 in the generation of type I interferon (IFN-I) from PAMs were analyzed by using the cGAS and STING specific siRNA, inhibitors BX795 and BAY 11-7082. The results showed that the expression levels of IFN-I increased significantly at 48 h after infection with PCV2 (P<0.05), the mRNA expression levels of cGAS increased significantly at 48 h and 72 h after infection (P<0.01), the mRNA expression levels of STING increased significantly at 72 h after infection (P<0.01), and the mRNA expression levels of TBK1 and IRF3 increased at 48 h after infection (P<0.01). The protein expression levels of STING, TBK1 and IRF3 in PAMs infected with PCV2 were increased, the content of NF-κB/p65 was decreased, and the nuclear entry of NF-κB/p65 and IRF3 was promoted. After knocking down cGAS or STING expression by siRNA, the expression level of IFN-I was significantly decreased after PCV2 infection for 48 h (P<0.01). BX795 and BAY 11-7082 inhibitors were used to inhibit the expression of IRF3 and NF-κB, the concentration of IFN-I in BX795-treated group was significantly reduced than that of the PCV2 group (P<0.01), while no significant difference was observed between the BAY 11-7028 group and the PCV2 group. The results showed that PAMs infected with PCV2 induced IFN-I secretion through the cGAS/STING/TBK1/IRF3 signaling pathway.
Animals
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Cells, Cultured
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Circovirus
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Interferon Type I/genetics*
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Macrophages, Alveolar/virology*
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Membrane Proteins/metabolism*
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Nucleotidyltransferases/metabolism*
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Signal Transduction
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Swine
10.Effect and Mechanism of Action of Epimedii Folium Polysaccharides on Mice with Exercise-induced Fatigue Based on p38 MAPK/NF-κB Signaling Pathway
Yue ZOU ; Min XIAO ; Yuhao MENG ; Kunyang TANG ; Xiaocui JIANG ; Zhipeng FANG
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(10):20-28
ObjectiveTo study the effects of Epimedii Folium polysaccharides on mice with exercise-induced fatigue and explore its possible mechanism of action. MethodICR male mice screened by swimming training were randomly divided into a control group, model group, vitamin C group, and low, medium, and high dose groups of Epimedii Folium polysaccharides, with eight mice in each group. The exercise-induced fatigue model was established by weight-bearing swimming training in each group except for the control group. After two weeks of weight-bearing swimming, the Epimedii Folium polysaccharide groups were given 100, 200, 400 mg∙kg-1 of Epimedii Folium polysaccharides by gavage, and the vitamin C group was given 200 mg∙kg-1 of vitamin C by gavage. The control group and the model group were given equal amounts of saline for 14 d. At the end of the experimental period, the body mass of the mice in each group and the time of last swimming due to exhaustion were recorded. Serum urea nitrogen (BUN), lactic acid (LA), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidation (GSH-Px), myoglycogen (MG) in skeletal muscle, hepatic glycogen (HG) in the liver were detected by kits. Hematoxylin-eosin (HE) staining was used to observe the pathological changes in muscle tissue. Western blot was used to detect the protein expression of p38 mitogen-activated protein kinase (p38 MAPK), phosphorylation (p)-p38 MAPK, extracellular signal-regulated kinase1/2 (ERK1/2), nuclear factor-κB (NF-κB), p-NF-κB, interleukin-1β (IL-1β), and interleukin-6 (IL-6) in muscle tissue. The immunofluorescence (IF) method was used to detect the expression of tumor necrosis factor-α (TNF-α) in skeletal muscle tissue of mice in each group. ResultCompared with the control group, the body mass of mice in the model group decreased, and the time of last swimming due to exhaustion decreased (P<0.01). In addition, there were significantly higher serum levels of the fatigue metabolites LA, LDH, BUN, and lipid peroxidation product MDA (P<0.01) and decreased levels of MG, HG, SOD, and GSH-Px (P<0.01). The protein expressions of p-p38 MAPK, ERK1/2, p-NF-κB, IL-1β, IL-6, and TNF-α in skeletal muscle tissue were significantly higher than those of the control group (P<0.01). Compared with the model group, the body mass and time of last swimming due to exhaustion of the mice in the low, medium, and high dose groups of Epimedii Folium polysaccharides and the vitamin C group were increased (P<0.05, P<0.01), and the contents of LA, LDH, BUN, and MDA were significantly decreased (P<0.05, P<0.01). The levels of MG, HG, SOD, and GSH-Px increased (P<0.05, P<0.01), and the protein expression levels of p-p38 MAPK, ERK, p-NF-κB, IL-1β, IL-6, and TNF-α in skeletal muscle tissue decreased (P<0.05, P<0.01). ConclusionEpimedii Folium polysaccharides can play a role in alleviating exercise-induced fatigue by inhibiting the p38 MARK/NF-κB signaling pathway, thereby reducing the accumulation of metabolites, improving the activity of antioxidant enzymes, increasing the glycogen content of the body, and reducing inflammation in skeletal muscle.