OBJECTIVES: The core pathology of osteoporosis lies in bone resorption exceeding bone formation; thus, promoting osteogenesis is a key therapeutic strategy. The osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) forms the biological basis of bone formation. Astragaloside IV (A-IV), a major active component of Astragalus membranaceus, is known to enhance osteogenesis, but its precise molecular mechanisms remain unclear. This study aims to investigate the effects of A-IV on the proliferation and osteogenic differentiation of BMSCs from osteoporotic rats and to elucidate its molecular mechanism through the regulation of microRNA-21 (miR-21) and Notch2 expression. METHODS: After 1 week of adaptive feeding, mature female SD rats were randomly divided into a sham-operated (Sham) group (n=4) and an ovariectomized (OVX) group (n=8) to establish an osteoporosis model. Twelve weeks after surgery, BMSCs were isolated from femoral bone marrow and cultured. Cells were divided into a S-BMSCs group (from Sham), an O-BMSCs group (from OVX), and an A-BMSCs group (from OVX-derived BMSCs treated with A-IV). S-BMSCs and O-BMSCs were induced for osteogenic differentiation using osteogenic induction medium, whereas A-BMSCs were treated with A-IV before induction. Flow cytometry was used to identify mesenchymal stem cell surface markers (CD29) and hematopoietic stem cell marker (CD34) to confirm BMSC characteristics. Cell proliferation was assessed using the methyl thiazolyl tetrazolium (MTT) assay. Alizarin red staining was performed to quantify calcium nodule formation, and alkaline phosphatase (ALP) activity assays were used to evaluate osteogenic differentiation. Real-time reverse transcription PCR (real-time RT-PCR) was used to detect changes in osteogenic-related genes, runt-related transcription factor 2 (Runx2) and osteopontin (OPN), as well as miR-21 expression. Western blotting was performed to assess Runx2, OPN, and Notch2 protein expression. RESULTS: Flow cytometry confirmed that O-BMSCs retained the phenotypic characteristics of mesenchymal stem cells. A-IV significantly enhanced the proliferation of BMSCs from osteoporotic rats (P<0.05), increased ALP activity, and upregulated the mRNA and protein expression of Runx2 and OPN (P<0.05). Bioinformatic and experimental analyses demonstrated that miR-21 directly targeted Notch2. A-IV treatment increased miR-21 expression while suppressing Notch2 protein expression and inhibiting activation of the Notch signaling pathway (P<0.05). CONCLUSIONS Astragaloside IV promotes the osteogenic differentiation of BMSCs derived from osteoporotic rats by upregulating miR-21 expression and inhibiting the key Notch signaling protein Notch2, thereby relieving the Notch2-mediated suppression of osteogenesis.
Animals ; Triterpenes/pharmacology* ; Saponins/pharmacology* ; Osteogenesis/drug effects* ; MicroRNAs/metabolism* ; Rats, Sprague-Dawley ; Female ; Cell Differentiation/drug effects* ; Mesenchymal Stem Cells/drug effects* ; Signal Transduction/drug effects* ; Osteoporosis/pathology* ; Rats ; Cells, Cultured ; Receptor, Notch2/metabolism* ; Receptors, Notch/metabolism* ; Ovariectomy ; Cell Proliferation/drug effects*

Ulcerative colitis (UC) is an inflammatory condition of the intestine, resulting from an increase in oxidative stress and pro-inflammatory mediators. In this study, the extract of endophytic bacterium Rhizobium aegyptiacum was prepared for the first time using liquid chromatography-mass spectrometry (LC-MS). In addition, also for the first time, the protective potential of R. aegyptiacum was revealed using an in vivo rat model of UC. The animals were grouped into four categories: normal control (group I), R. aegyptiacum (group II), acetic acid (AA)‍-induced UC (group III), and R. aegyptiacum-treated AA-induced UC (group IV). In group IV, R. aegyptiacum was administered at 0.2 mg/kg daily for one week before and two weeks after the induction of UC. After sacrificing the rats on the last day of the experiment, colon tissues were collected and subjected to histological, immunohistochemical, and biochemical investigations. There was a remarkable improvement in the histological findings of the colon tissues in group IV, as revealed by hematoxylin and eosin (H&E) staining, Masson's trichrome staining, and periodic acid-Schiff (PAS) staining. Normal mucosal surfaces covered with a straight, intact, and thin brush border were revealed. Goblet cells appeared magenta in color, and there was a significant decrease in the distribution of collagen fibers in the mucosa and submucosal connective tissues. All these findings were comparable to the respective characteristics of the control group. Regarding cyclooxygenase-2 (COX-2) immunostaining, a weak immune reaction was shown in most cells. Moreover, the colon tissues were examined using a scanning electron microscope, which confirmed the results of histological assessment. A regular polygonal unit pattern was seen with crypt orifices of different sizes and numerous goblet cells. Furthermore, the levels of catalase (CAT), myeloperoxidase (MPO), nitric oxide (NO), interleukin-6 (IL-6), and interlukin-1β (IL-1β) were determined in the colonic tissues of the different groups using colorimetric assay and enzyme-linked immunosorbent assay (ELISA). In comparison with group III, group IV exhibited a significant rise (P<0.05) in the CAT level but a substantial decline (P<0.05) in the NO, MPO, and inflammatory cytokine (IL-6 and IL-1β) levels. Based on reverse transcription-quantitative polymerase chain reaction (RT-qPCR), the tumor necrosis factor-‍α (TNF-‍α) gene expression was upregulated in group III, which was significantly downregulated (P<0.05) by treatment with R. aegyptiacum in group IV. On the contrary, the heme oxygenase-1 (HO-1) gene was substantially upregulated in group IV. Our findings imply that the oral consumption of R. aegyptiacum ameliorates AA-induced UC in rats by restoring and reestablishing the mucosal integrity, in addition to its anti-oxidant and anti-inflammatory effects. Accordingly, R. aegyptiacum is potentially effective and beneficial in human UC therapy, which needs to be further investigated in future work.
Animals ; Colitis, Ulcerative/prevention & control* ; Rats ; Male ; Rhizobium ; Disease Models, Animal ; Colon/pathology* ; Rats, Sprague-Dawley ; Oxidative Stress ; Cyclooxygenase 2/metabolism*

OBJECTIVES: The use of stem cells is a promising strategy for seizure treatment owing to their unique characteristics. We investigated the role of endothelial progenitor cells (EPCs) in a pentylenetetrazole (PTZ)‍-induced rat seizure model. A selected panel of long noncoding RNAs (lncRNAs), which maintain an elaborate balance in brain neural regulatory networks as well as the autophagy pathway, was also targeted. METHODS: The impact of intravenously administered EPCs on PTZ-induced kindling in rats was evaluated by measuring the expression of neuronal damage markers, neurotrophic factors, and relevant lncRNA genes. Rat behavior was assessed using Y-maze test and open field test (OFT). RESULTS: EPCs mitigated seizure-associated neurological damage and reversed PTZ-induced working memory and locomotor activity deficits, as evidenced by improved performance in the Y-maze test and OFT. EPC treatment reversed the downregulation of the expression of the lncRNAs Evf2, Pnky, Dlx1, APF, HOTAIR, and FLJ11812. EPCs also boosted vascular endothelial growth factor (VEGF) expression. The ameliorative effect achieved by EPCs was comparable to that produced by valproate. CONCLUSIONS These findings indicate that EPCs ameliorate kindling epileptic seizures and their associated abnormalities and that the effect of EPCs may be mediated via the upregulation of certain regulatory lncRNAs.
Animals ; Pentylenetetrazole ; RNA, Long Noncoding ; Seizures/therapy* ; Rats ; Male ; Endothelial Progenitor Cells/transplantation* ; Rats, Sprague-Dawley ; Kindling, Neurologic ; Vascular Endothelial Growth Factor A/metabolism* ; Disease Models, Animal

BACKGROUND: Knee osteoarthritis (OA) is still challenging to prevent or treat. Enhanced endoplasmic reticulum (ER) stress and increased pyroptosis in chondrocytes may be responsible for cartilage degeneration. This study aims to investigate the effect of ER stress on chondrocyte pyroptosis and the upstream regulatory mechanisms, which have rarely been reported. METHODS: The expression of the histone methyltransferase enhancer of zeste homolog 2 (EZH2), microRNA-142-3p (miR-142-3p), and high mobility group box 1 (HMGB1) and the levels of ER stress, pyroptosis, and metabolic markers in normal and OA chondrocytes were investigated by western blotting, quantitative polymerase chain reaction, immunohistochemistry, fluorescence in situ hybridization, fluorescein amidite-tyrosine-valine-alanine-aspartic acid-fluoromethyl ketone (FAM-YVAD-FMK)/Hoechst 33342/propidium iodide (PI) staining, lactate dehydrogenase (LDH) release assays, and cell viability assessments. The effects of EZH2, miR-142-3p, and HMGB1 on ER stress and pyroptosis and the hierarchical regulatory relationship between them were analyzed by chromatin immunoprecipitation, luciferase reporters, gain/loss-of-function assays, and rescue assays in interleukin (IL)-1β-induced OA chondrocytes. The mechanistic contribution of EZH2, miR-142-3p, and HMGB1 to chondrocyte ER stress and pyroptosis and therapeutic prospects were validated radiologically, histologically, and immunohistochemically in surgically induced OA rats. RESULTS: Increased EZH2 and HMGB1, decreased miR-142-3p, enhanced ER stress, and activated pyroptosis in chondrocytes were associated with OA occurrence and progression. EZH2 and HMGB1 exacerbated and miR-142-3p alleviated ER stress and pyroptosis in OA chondrocytes. EZH2 transcriptionally silenced miR-142-3p via H3K27 trimethylation, and miR-142-3p posttranscriptionally silenced HMGB1 by targeting the 3'-UTR of the HMGB1 gene. Moreover, ER stress mediated the effects of EZH2, miR-142-3p, and HMGB1 on chondrocyte pyroptosis. In vivo experiments mechanistically validated the hierarchical regulatory relationship between EZH2, miR-142-3p, and HMGB1 and their effects on chondrocyte ER stress and pyroptosis. CONCLUSIONS A novel EZH2/miR-142-3p/HMGB1 axis mediates chondrocyte pyroptosis and cartilage degeneration by regulating ER stress in OA, contributing novel mechanistic insights into OA pathogenesis and providing potential targets for future therapeutic research.
Enhancer of Zeste Homolog 2 Protein/genetics* ; Osteoarthritis, Knee/pathology* ; Chondrocytes/metabolism* ; Pyroptosis/physiology* ; HMGB1 Protein/genetics* ; MicroRNAs/metabolism* ; Endoplasmic Reticulum Stress/genetics* ; Humans ; Animals ; Rats ; Male ; Rats, Sprague-Dawley ; Middle Aged

BACKGROUND: Osteoarthritis (OA) is a prevalent joint disorder that significantly impairs quality of life among elderly individuals because of chronic pain and physical disability. As the global burden of OA continues to rise, novel therapeutic strategies are urgently needed. Kaempferide (KA), a flavonoid derived from traditional Chinese herbal medicine, is known for its anti-inflammatory properties. However, the effect of KA on the progression of OA has not been well investigated. This study aimed to explore the therapeutic potential of KA in an OA model and investigate the underlying mechanisms via transcriptomic sequencing. METHODS: An in vitro OA model was established using SW1353 cells treated with interleukin-1 beta (IL-1β) and different concentrations of KA (30, 60, or 90 μmol/L) for 24 h. The anti-inflammatory effects of KA were assessed using quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blotting. In vivo , a papain-induced OA rat model was used to evaluate the therapeutic effects of KA through histological and behavioral analyses. Transcriptomic sequencing was performed to explore the differentially expressed genes (DEGs) and related signaling pathways. Statistical analysis was conducted using one-way analysis of variance. RESULTS: KA significantly increased cell viability in the OA chondrocyte model and downregulated the expression of inflammatory cytokines and cartilage degradation markers, with the greatest reduction observed at 90 μmol/L. In vivo , KA treatment mitigated cartilage degradation and improved gait behavior in OA rats. Transcriptomic analysis revealed substantial modulation of DEGs, implicating the hypoxia-inducible factor-1 (HIF-1) signaling pathway as a key mechanism. Further blocking and rescue experiments revealed that KA regulated key molecules within the HIF-1 pathway, specifically interferon-gamma (IFN-γ) and hypoxia-inducible factor 1-alpha (HIF-1α), confirming their critical roles in mediating the therapeutic effects of KA. CONCLUSION KA inhibited the progression of OA by targeting the HIF-1 signaling pathway, reducing inflammation, and cartilage degradation.
Animals ; Osteoarthritis/metabolism* ; Signal Transduction/drug effects* ; Rats ; Rats, Sprague-Dawley ; Humans ; Male ; Hypoxia-Inducible Factor 1/metabolism* ; Interleukin-1beta

The present study aimed to investigate the effects of eccentric treadmill exercise on adaptive hypertrophy of skeletal muscle in rats. Thirty-two 3-month-old Sprague Dawley (SD) rats were selected and randomly assigned to one of the four groups based on their body weights: 2-week quiet control group (2C), 2-week downhill running exercise group (2E), 4-week quiet control group (4C), and 4-week downhill running exercise group (4E). The downhill running protocol for rats in the exercise groups involved slope of -16°, running speed of 16 m/min, training duration of 90 min, and 5 training sessions per week. Twenty-four hours after the final session of training, all the four groups of rats underwent an exhaustion treadmill exercise. After resting for 48 h, all the rats were euthanized and their gastrocnemius muscles were harvested for analysis. HE staining was used to measure the cross-sectional area (CSA) and diameter of muscle fibers. Transmission electron microscope was used to observe the ultrastructural changes in muscle fibers. Purithromycin surface labeling translation method was used to measure protein synthesis rate. Immunofluorescence double labeling was used to detect the colocalization levels of lysosomal-associated membrane protein 2 (Lamp2)-leucyl-tRNA synthetase (LARS) and Lamp2-mammalian target of rapamycin (mTOR). Western blot was used to measure the protein expression levels of myosin heavy chain (MHC) IIb and LARS, as well as the phosphorylation levels of mTOR, p70 ribosomal protein S6 kinase (p70S6K), and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1). The results showed that, compared with the 2C group rats, the 2E group rats showed significant increases in wet weight of gastrocnemius muscle, wet weight/body weight ratio, running distance, running time, pre- and post-exercise blood lactate levels, myofibrillar protein content, colocalization levels of Lamp2-LARS and Lamp2-mTOR, and LARS protein expression. Besides these above changes, compared with the 4C group, the 4E group further exhibited significantly increased fiber CSA, fiber diameter, protein synthesis rate, and phosphorylation levels of mTOR, p70S6K, and 4E-BP1. Compared with the quiet control groups, the exercise groups exhibited ultrastructural damage of rat gastrocnemius muscle, which was more pronounced in the 4E group. These findings suggest that eccentric treadmill exercise may promote mTOR translocation to lysosomal membrane, activating mTOR signaling via up-regulating LARS expression. This, in turn, increases protein synthesis rate through the mTOR-p70S6K-4E-BP1 signaling pathway, promoting protein deposition and inducing adaptive skeletal muscle hypertrophy. Although the ultrastructural changes of skeletal muscle are more pronounced, the relatively long training cycles during short-term exercise periods have a more significant effect on promoting gastrocnemius muscle protein synthesis and adaptive hypertrophy.
Animals ; Rats, Sprague-Dawley ; Physical Conditioning, Animal/physiology* ; Rats ; Muscle, Skeletal/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Male ; Hypertrophy ; Adaptation, Physiological/physiology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Ribosomal Protein S6 Kinases, 70-kDa/metabolism* ; Intracellular Signaling Peptides and Proteins

The present study aimed to explore whether hydrogen sulfide (H₂S) improved hypoxic pulmonary hypertension (HPH) in rats by inhibiting aerobic glycolysis-pyroptosis. Male Sprague-Dawley (SD) rats were randomly divided into normal group, normal+NaHS group, hypoxia group, and hypoxia+NaHS group, with 6 rats in each group. The control group rats were placed in a normoxic (21% O₂) environment and received daily intraperitoneal injections of an equal volume of normal saline. The normal+NaHS group rats were placed in a normoxic environment and intraperitoneally injected with 14 μmol/kg NaHS daily. The hypoxia group rats were placed in a hypoxia chamber, and the oxygen controller inside the chamber maintained the oxygen concentration at 9% to 10% by controlling the N₂ flow rate. An equal volume of normal saline was injected intraperitoneally every day. The hypoxia+NaHS group rats were also placed in an hypoxia chamber and intraperitoneally injected with 14 μmol/kg NaHS daily. After the completion of the four-week modeling, the mean pulmonary artery pressure (mPAP) of each group was measured using right heart catheterization technique, and the right ventricular hypertrophy index (RVHI) was weighed and calculated. HE staining was used to observe pathological changes in lung tissue, Masson staining was used to observe fibrosis of lung tissue, and Western blot was used to detect protein expression levels of hexokinase 2 (HK2), pyruvate dehydrogenase (PDH), pyruvate kinase isozyme type M2 (PKM2), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), GSDMD-N-terminal domain (GSDMD-N), Caspase-1, interleukin-1β (IL-1β) and IL-18 in lung tissue. ELISA was used to detect contents of IL-1β and IL-18 in lung tissue. The results showed that, compared with the normal control group, there were no significant changes in all indexes in the normal+NaHS group, while the hypoxia group exhibited significantly increased mPAP and RVHI, thickened pulmonary vascular wall, narrowed lumen, increased collagen fibers, up-regulated expression levels of aerobic glycolysis-related proteins (HK2 and PKM2), up-regulated expression levels of pyroptosis-related proteins (NLRP3, GSDMD-N, Caspase-1, IL-1β, and IL-18), and increased contents of IL-1β and IL-18. These changes of the above indexes in the hypoxia group were significantly reversed by NaHS. These results suggest that H₂S can improve rat HPH by inhibiting aerobic glycolysis-pyroptosis.
Animals ; Rats, Sprague-Dawley ; Male ; Hypertension, Pulmonary/metabolism* ; Glycolysis/drug effects* ; Hydrogen Sulfide/therapeutic use* ; Hypoxia/complications* ; Rats ; Pyroptosis/drug effects*

The hippocampus, a major component of the limbic system, is the most important region related to emotion regulation and memory processing. Cognitive impairment and depressive symptoms observed in Alzheimer's disease (AD) patients may be attributed to hippocampal damage caused by amyloid β-protein (Aβ). Our previous studies have demonstrated that a steroid sulfatase inhibitor DU-14 can enhance hippocampal synaptic plasticity and spatial memory abilities in a chronic AD murine model by counteracting the toxic effects of Aβ. However, limited experimental evidence exists regarding the efficacy of steroid sulfatase inhibitor on depressive symptoms in AD animal models. In this study, we investigated the effects of DU-14 on depressive symptoms and theta-band neuronal oscillations in rats with intrahippocampal injection of Aβ_1-42 using various behavioral tests such as sucrose preference test, tail suspension test, forced swimming test, and in vivo hippocampal local field potential (LFP) recording. The results demonstrated that, in comparison to the control group: (1) rats in the Aβ group exhibited a decrease in sucrose preference, indicating a loss of interest in pleasurable activities; (2) rats in the Aβ group displayed aggravated depressive-like behavior characterized by prolonged immobility time during tail suspension and forced swimming tests; (3) Aβ disrupted the induction of theta rhythm via tail pinch stimulation, and resulted in a significant reduction in peak power of theta rhythm. In contrast to the Aβ group, pretreatment with DU-14 resulted in: (1) a significant improvement in Aβ-induced anhedonia, as evidenced by increased sucrose preference; (2) significant alleviation of Aβ-induced despair and depressive-like behaviors, reflected by reduced immobility time during tail suspension and forced swimming tests; (3) successful mitigation of Aβ-mediated inhibition on bilateral hippocampal theta rhythm. These findings indicate that steroid sulfatase inhibitor DU-14 can counteract neurotoxicity induced by Aβ, and prevent Aβ-induced depressive-like behavior and suppression of theta rhythm.
Animals ; Amyloid beta-Peptides/toxicity* ; Rats ; Depression/physiopathology* ; Theta Rhythm/drug effects* ; Hippocampus/physiopathology* ; Male ; Rats, Sprague-Dawley ; Alzheimer Disease/physiopathology* ; Steryl-Sulfatase/antagonists & inhibitors* ; Peptide Fragments ; Behavior, Animal/drug effects*

The aim of this study was to investigate the contribution of lung zinc ions to pathogenesis of lung ischemia/reperfusion (I/R) injury in rats. Male Sprague Dawley (SD) rats were randomly divided into control group, lung I/R group (I/R group), lung I/R + low-dose zinc chloride group (LZnCl₂+I/R group), lung I/R + high-dose ZnCl₂ group (HZnCl₂+I/R group), lung I/R + medium-dose ZnCl₂ group (MZnCl₂+I/R group) and TPEN+MZnCl₂+I/R group (n = 8 in each group). Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of zinc ions in lung tissue. The degree of lung tissue injury was analyzed by observing HE staining, alveolar damage index, lung wet/dry weight ratio and lung tissue gross changes. TUNEL staining was used to detect cellular apoptosis in lung tissue. Western blot and RT-qPCR were used to determine the protein expression levels of caspase-3 and ZIP8, as well as the mRNA expression levels of zinc transporters (ZIP, ZNT) in lung tissue. The mitochondrial membrane potential (MMP) of lung tissue was detected by JC-1 MMP detection kit. The results showed that, compared with the control group, the lung tissue damage, lung wet/dry weight ratio and alveolar damage index were significantly increased in the I/R group. And in the lung tissue, the concentration of Zn²⁺ was markedly decreased, while the cleaved caspase-3/caspase-3 ratio and apoptotic levels were significantly increased. The expression levels of ZIP8 mRNA and protein were down-regulated significantly, while the mRNA expression of other zinc transporters remained unchanged. There was also a significant decrease in MMP. Compared with the I/R group, both MZnCl₂+I/R group and HZnCl₂+I/R group exhibited significantly reduced lung tissue injury, lung wet/dry weight ratio and alveolar damage index, increased Zn²⁺ concentration, decreased ratio of cleaved caspase-3/caspase-3 and apoptosis, and up-regulated expression levels of ZIP8 mRNA and protein. In addition, the MMP was significantly increased in the lung tissue. Zn²⁺ chelating agent TPEN reversed the above-mentioned protective effects of medium-dose ZnCl₂ on the lung tissue in the I/R group. The aforementioned results suggest that exogenous administration of ZnCl₂ can improve lung I/R injury in rats.
Animals ; Reperfusion Injury/pathology* ; Male ; Rats, Sprague-Dawley ; Rats ; Chlorides/administration & dosage* ; Lung/pathology* ; Zinc Compounds/administration & dosage* ; Apoptosis/drug effects* ; Caspase 3/metabolism* ; Cation Transport Proteins/metabolism*

OBJECTIVE: To assess the impacts of electroacupuncture (EA) on the gait, oxidative stress, inflammatory reaction, and protein degradation in the rats of denervated skeletal muscle atrophy, and explore the potential mechanism of EA for alleviating denervated skeletal muscle atrophy. METHODS: Forty male SD rats, 8 weeks old, were randomly assigned to a sham-surgery group, a model group, an EA group, and a p38 MAPK inhibitor group, with 10 rats in each group. The right sciatic nerve was transected to establish a rat model of denervated skeletal muscle atrophy in the model group, the EA group and the p38 MAPK inhibitor group. In the sham-surgery group, the nerve was exposed without transection. One day after successful modeling, the rats in the EA group received EA at "Huantiao" (GB30) and "Zusanli" (ST36) on the right side, using a continuous wave with a frequency of 2 Hz and current intensity of 1 mA, for 15 min in each session, EA was delivered once a day, 6 times a week. In the p38 MAPK inhibitor group, the rats received the intraperitoneal injection with SB203580 (5 mg/kg), once a day, 6 times a week. The intervention was composed of 3 weeks in each group. After the intervention completion, the CatWalk XT 10.6 animal gait analysis system was used to record the gait parameters of rats. The wet weight ratio of the gastrocnemius muscle was calculated after the sample collected. Using HE staining, the fiber morphology and cross-sectional area of the gastrocnemius muscle were observed; ELISA was employed to measure the content of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α in the gastrocnemius muscle; the biochemical hydroxyamine method was adopted to detect the content of superoxide dismutase (SOD) and malondialdehyde (MDA) in the gastrocnemius muscle; with immunohistochemistry and Western blot used, the expression of p38 mitogen-activated protein kinase (p38 MAPK), phosphorylated (p)-p38 MAPK, muscle atrophy F-box gene (Atrogin-1), muscle RING finger 1 (Murf-1), nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) was detected in the gastrocnemius muscle. RESULTS: Compared to the sham-surgery group, in the model group, the standing duration, the swing time and the step cycle were increased (P<0.001), the footprint area of the maximum contact time, the print area, the average intensity of the maximum contact time, the average intensity, the swing speed, and the step length were decreased (P<0.001); the wet weight ratio of gastrocnemius muscle and fiber cross-sectional area were reduced (P<0.001); the content of IL-6, IL-1β, TNF-α and MDA in gastrocnemius muscle elevated (P<0.001), and that of SOD reduced (P<0.001); the positive and protein expression of p-p38 MAPK, Atrogin-1 and Murf-1 elevated (P<0.001) and that of Nrf2 and HO-1 dropped (P<0.001). When compared with the model group, in the EA group and the p38 MAPK inhibitor group, the standing duration, the swing time and the step cycle decreased (P<0.01), the footprint area of the maximum contact time, the print area, the average intensity of the maximum contact time, the average intensity, the swing speed, and the step length increased (P<0.01); the wet weight ratio of gastrocnemius muscle and fiber cross-sectional area were improved (P<0.01, P<0.05); the content of IL-6, IL-1β, TNF-α and MDA in gastrocnemius muscle dropped (P<0.05, P<0.01), and that of SOD elevated (P<0.01, P<0.05); the positive and protein expression of p-p38 MAPK, Atrogin-1 and Murf-1 dropped (P<0.01, P<0.05) and that of Nrf2 and HO-1 increased (P<0.01, P<0.05). CONCLUSION Electroacupuncture may alleviate skeletal muscle atrophy in denervated skeletal muscle atrophy rats by mediating the p38 MAPK activity, thereby suppressing oxidative stress, inflammatory reaction, and protein degradation.
Animals ; Electroacupuncture ; Male ; Rats ; p38 Mitogen-Activated Protein Kinases/genetics* ; Rats, Sprague-Dawley ; Muscular Atrophy/metabolism* ; Muscle, Skeletal/metabolism* ; Humans ; Signal Transduction ; Superoxide Dismutase/genetics* ; Tumor Necrosis Factor-alpha/genetics* ; Oxidative Stress ; MAP Kinase Signaling System ; Acupuncture Points