OBJECTIVE: To investigate the potential mechanism by which electroacupuncture (EA) induces macrophage polarization to promote muscle satellite cell proliferation and differentiation, accelerating the repair of acute skeletal muscle injury. METHODS: Forty-two SPF-grade SD rats were randomly divided into three groups: a blank group (n=6), a model group (n=18), and an EA group (n=18). The model and EA groups established acute blunt contusion model of the right gastrocnemius muscle using a self-made striking device. From day 1 after modeling, rats in the EA group received EA at "Chengshan" (BL57) and "Yanglingquan" (GB34) on the right side, using disperse-dense wave with a frequency of 2 Hz/100 Hz and a current of approximately 2 mA. The EA treatment was administered once daily for 30 minutes for 3, 7, or 14 days based on the designated sampling time points. Gait analysis was performed using the Cat Walk XT^TM system. Hematoxylin-eosin (HE) staining was used to observe the morphological changes in the gastrocnemius muscle. Masson staining was applied to evaluate collagen fiber content. Immunofluorescence was used to detect the expression of proliferating cell nuclear antigen (PCNA) in muscle satellite cells. Immunohistochemistry was used to assess the expression levels of CD68 and CD206, markers of macrophages. Serum levels of pro-inflammatory cytokines (TNF-α, IL-1β) and anti-inflammatory cytokines (IL-10, IL-13) were detected using ELISA. RESULTS: Compared with the blank group, the model group showed a significant reduction in average movement speed on days 3 and 7 after modeling (P<0.05), and a decrease in the right hind limb stride length on day 3 (P<0.05). Compared with the model group, the EA group showed increased average movement speed and right hind limb stride length on day 7 (P<0.05). In the blank group, the gastrocnemius muscle on the right side showed uniform and consistent inter-fiber spacing, with neatly and regularly arranged muscle cells. In contrast, the model group exhibited enlarged inter-fiber spacing, edema, and significant infiltration of red blood cells and inflammatory cells, with progressively increasing fibrosis over time. By day 14 after modeling, the EA group showed a return to baseline levels of inflammatory cell infiltration, and the degree of fibrosis was significantly lower than that observed in the model group. Compared with the blank group, the ratio of collagen fibers in the gastrocnemius muscle of the model group increased significantly on days 3, 7, and 14 after modeling (P<0.05). Compared with the model group, the EA group exhibited a lower collagen fiber ratio on days 3, 7, and 14 (P<0.05). Compared with the blank group, PCNA positive expression in the gastrocnemius muscle of the model group was significantly increased on days 3, 7, and 14 after modeling (P<0.05). Compared with the model group, the EA group exhibited significantly higher PCNA positive expression on days 3 and 7 (P<0.05). Compared with the blank group, the model group showed a significant increase in CD68-positive macrophage expression in the gastrocnemius muscle on day 3 after modeling (P<0.05), while CD206-positive macrophage expression increased on days 3, 7, and 14 (P<0.05). Compared with the model group, CD68 expression was significantly lower in the EA group on day 3 (P<0.05), whereas CD206 expression was significantly higher on days 3 and 7 (P<0.05), peaking on day 7 with CD206 expression. Compared with the blank group, serum TNF-α levels were significantly elevated in the model group on days 3 and 7 after modeling (P<0.05), while serum IL-1β levels were increased on days 3, 7, and 14 (P<0.05). Serum IL-10 and IL-13 levels were significantly higher on day 7 after modeling (P<0.05). Compared with the model group, the EA group exhibited lower serum TNF-α level on day 3 (P<0.05) and reduced serum IL-1β levels on days 3 and 7 (P<0.05), while serum IL-10 and IL-13 levels were significantly increased on day 7 (P<0.05). CONCLUSION EA could promote the repair of acute blunt contusion-induced gastrocnemius muscle injury by regulating the proliferation and differentiation of muscle satellite cells. This process is closely related to macrophage polarization.
Animals ; Electroacupuncture ; Rats, Sprague-Dawley ; Rats ; Macrophages/immunology* ; Muscle, Skeletal/immunology* ; Male ; Humans ; Female ; Tumor Necrosis Factor-alpha/immunology* ; Cell Proliferation

OBJECTIVE: To evaluate the effect of biodegradable magnesium alloy materials in promoting tendon-bone healing during rotator cuff tear repair and to investigate their potential underlying biological mechanisms. METHODS: Forty-eight 8-week-old Sprague Dawley rats were taken and randomly divided into groups A, B, and C. Rotator cuff tear models were created and repaired using magnesium alloy sutures in group A and Vicryl Plus 4-0 absorbable sutures in group B, while only subcutaneous incisions and sutures were performed in group C. Organ samples of groups A and B were taken for HE staining at 1 and 2 weeks after operation to evaluate the safety of magnesium alloy, and specimens from the supraspinatus tendon and proximal humerus were harvested at 2, 4, 8, and 12 weeks after operation. The specimens were observed macroscopically at 4 and 12 weeks after operation. Biomechanical tests were performed at 4, 8, and 12 weeks to test the ultimate load and stiffness of the healing sites in groups A and B. At 2, 4, and 12 weeks, the specimens were subjected to the following tests: Micro-CT to evaluate the formation of bone tunnels in groups A and B, HE staining and Masson staining to observe the regeneration of fibrocartilage at the tendon-bone interface after decalcification and sectioning, and Goldner trichrome staining to evaluate the calcification. Immunohistochemical staining was performed to detect the expressions of angiogenic factors, including vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2), as well as osteogenic factors at the tendon-bone interface. Additionally, immunofluorescence staining was used to examine the expressions of Arginase 1 and Integrin beta-2 to assess M1 and M2 macrophage polarization at the tendon-bone interface. The role of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in tendon-bone healing was further analyzed using real-time fluorescence quantitative PCR. RESULTS: Analysis of visceral sections revealed that magnesium ions released during the degradation of magnesium alloys did not cause significant toxic effects on organs such as the heart, liver, spleen, lungs, and kidneys, indicating good biosafety. Histological analysis further demonstrated that fibrocartilage regeneration at the tendon-bone interface in group A occurred earlier, and the amount of fibrocartilage was significantly greater compared to group B, suggesting a positive effect of magnesium alloy material on tendon-bone interface repair. Additionally, Micro-CT analysis results revealed that bone tunnel formation occurred more rapidly in group A compared to group B, further supporting the beneficial effect of magnesium alloy on bone healing. Biomechanical testing showed that the ultimate load in group A was consistently higher than in group B, and the stiffness of group A was also greater than that of group B at 4 weeks, indicating stronger tissue-carrying capacity following tendon-bone interface repair and highlighting the potential of magnesium alloy in enhancing tendon-bone healing. Immunohistochemical staining results indicated that the expressions of VEGF and BMP-2 were significantly upregulated during the early stages of healing, suggesting that magnesium alloy effectively promoted angiogenesis and bone formation, thereby accelerating the tendon-bone healing process. Immunofluorescence staining further revealed that magnesium ions exerted significant anti-inflammatory effects by regulating macrophage polarization, promoting their shift toward the M2 phenotype. Real-time fluorescence quantitative PCR results demonstrated that magnesium ions could facilitate tendon-bone healing by modulating the PI3K/AKT signaling pathway. CONCLUSION Biodegradable magnesium alloy material accelerated fibrocartilage regeneration and calcification at the tendon-bone interface in rat rotator cuff tear repair by regulating the PI3K/AKT signaling pathway, thereby significantly enhancing tendon-bone healing.
Animals ; Rotator Cuff Injuries/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Wound Healing/drug effects* ; Alloys/pharmacology* ; Rats ; Proto-Oncogene Proteins c-akt/metabolism* ; Rotator Cuff/metabolism* ; Macrophages/metabolism* ; Magnesium/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Biocompatible Materials ; Bone Morphogenetic Protein 2/metabolism*

OBJECTIVE: To review the research progress of strontium (Sr) modified β-tricalcium phosphate composite biomaterials (SrTCP) promoting osteogenesis through immune regulation, and provides reference and theoretical support for the further development and research of SrTCP bone repair materials in bone tissue engineering in the future. METHODS: The literature about SrTCP promoting osteogenesis through immune regulation at home and abroad in recent years was extensively reviewed, and the preparation methods, immune mechanism and application of promoting osteogenesis were summarized and analyzed. RESULTS: The preparation methods of SrTCP include solid-state reaction sintering method, solution combustion quenching method, direct doping method, ion substitution method, etc. SrTCP has immune regulatory effects, which can play an immune regulatory role in inducing macrophage polarization, inducing angiogenesis and anti oxidative stress to promote osteogenesis. CONCLUSION At present, studies have shown that SrTCP can promote bone defect repair through immune regulation. Subsequent studies can start from the control of the optimal repair concentration and release rate of Sr, and further clarify the specific mechanism of SrTCP in promoting angiogenesis and anti oxidative stress, which is helpful to develop new materials for bone defect repair.
Calcium Phosphates/pharmacology* ; Strontium/pharmacology* ; Biocompatible Materials/pharmacology* ; Humans ; Osteogenesis/drug effects* ; Tissue Engineering/methods* ; Bone Substitutes/pharmacology* ; Bone Regeneration/drug effects* ; Animals ; Tissue Scaffolds/chemistry* ; Neovascularization, Physiologic/drug effects* ; Macrophages/immunology*

OBJECTIVE: To analyze the differences in the effects of different mechanical stimuli on cells, cytokines, and proteins in synovial fluid of osteoarthritis joints, and to elucidate the indirect mechanism by which mechanical signals remodel the synovial fluid microenvironment through tissue cells. METHODS: Systematically integrate recent literature, focusing on the regulatory effects of different mechanical stimuli on the physicochemical properties of synovial fluid. Analyze the dynamic process by which mechanical stimuli regulate secretory and metabolic activities through tissue cells, thereby altering the physicochemical properties of cytokines and proteins. RESULTS: Appropriate mechanical stimuli activate mechanical signals in chondrocytes, macrophages, and synovial cells, thereby influencing cellular metabolic activities, including inhibiting the release of pro-inflammatory factors and promoting the secretion of anti-inflammatory factors, and regulating the expression of matrix and inflammation-related proteins such as cartilage oligomeric matrix protein, peptidoglycan recognition protein 4, and matrix metalloproteinases. CONCLUSION Mechanical stimuli act on tissue cells, indirectly reshaping the synovial fluid microenvironment through metabolic activities, thereby regulating the pathological process of osteoarthritis.
Humans ; Osteoarthritis/physiopathology* ; Synovial Fluid/chemistry* ; Chondrocytes/metabolism* ; Cytokines/metabolism* ; Macrophages/metabolism* ; Stress, Mechanical ; Cartilage Oligomeric Matrix Protein/metabolism* ; Matrix Metalloproteinases/metabolism* ; Synovial Membrane/cytology*

Objectives miR-207 has been identified as being expressed in natural killer (NK) cell exosomes that play a role in disease progression; however, to date, there are no studies specifically linking miR-207 to tuberculosis (TB). Methods Bioinformatics methods employed for prediction, followed by a dual luciferase reporter assay to determine whether lysosome-associated membrane protein 2 (LAMP2) is targeted by miR-207. The experiments were divided into four groups using the liposome transfection method (OP-LAMP2 group: co-transfected with miR-207 mimics and LAMP2 overexpression plasmid; EP group: co-transfected with mimics NC and null-loaded plasmid; siLAMP2 group: transfected with siLAMP2; and siLAMP2-NC group: transfected with siLAMP2-NC). TB infection was modeled using H37Ra-infected Ana-1 cells. The impact of LAMP2 on intracellular mycobacterial load and clearance of extracellular residual mycobacteria were assessed by tuberculosis colony-forming unit counting. Flow cytometry was used to assess the total apoptosis rate. Real-time fluorescent quantitative PCR was conducted to determine the relative expression of LAMP2, apoptosis genes, pyroptosis genes, and autophagy genes. Western blot analysis was performed to measure the relative expression of LAMP2 proteins, apoptosis proteins, pyroptosis proteins, and autophagy proteins. Results Dual luciferase reporter assay test showed that there was a targeting relationship between LAMP2 and miR-207. The transfection model was successfully constructed under real-time fluorescent quantitative PCR and Western blot statistical analysis, and microscopic observation. The infection model was successfully established under microscopic observation. Colony forming unit counting revealed that the number of colonies in the OP-LAMP2 group was lower than that in the EP group, while the number of colonies in the siLAMP2 group was higher than that in the siLAMP2-NC group. Flow cytometry assay revealed that the total apoptosis in OP-LAMP2 group was lower than that in EP group, and the total apoptosis in siLAMP2 group was higher than that in siLAMP2-NC group. Real-time fluorescence quantitative PCR and Western blot analysis revealed that the relative expression of apoptosis and pyroptosis-related proteins and genes in the control group was lower in the OP-LAMP2 group compared to the EP group, and higher in the siLAMP2 group compared to the siLAMP2-NC group. Real-time fluorescence quantitative PCR detected that the relative expression of autophagy positively regulated genes Microtubule-associated protein 1 light chain 3(LC3)and Beclin1 in the OP-LAMP2 group was higher in the OP-LAMP2 group compared to the EP group, and lower in the siLAMP2 group compared to the siLAMP2-NC group, while the relative expression of negatively regulated autophagy genes followed the opposite trend to that of autophagy positively regulated genes. The relative expression of autophagy-related proteins was consistent with the trend of autophagy genes. Conclusions miR-207 enhances macrophage apoptosis, cellular pyroptosis and inhibits autophagy, promoting survival of Mycobacterium tuberculosis by targeting the autophagy-related protein LAMP2, thus offering a novel therapeutic direction for tuberculosis.
Lysosomal-Associated Membrane Protein 2/metabolism* ; MicroRNAs/metabolism* ; Mycobacterium tuberculosis/physiology* ; Autophagy/genetics* ; Humans ; Macrophages/metabolism* ; Apoptosis/genetics* ; Tuberculosis/metabolism* ; Cell Line ; Pyroptosis/genetics*

Allergic rhinitis (AR) is a chronic non-specific inflammatory disease of the nasal mucosa caused by abnormal activation of the immune system, with alterations in macrophage polarization playing a crucial role in its occurrence and development. Non-coding RNA has been found to play a key role in the polarization of macrophages. This study aims to explore the latest developments in research on the role of non-coding RNA-regulated macrophage polarization in the pathogenesis of AR, with the goal of identifying new approaches and potential targets for the diagnosis and treatment of AR.
Humans ; Rhinitis, Allergic/immunology* ; Macrophages/metabolism* ; RNA, Untranslated/genetics* ; Animals ; Macrophage Activation/genetics* ; Cell Polarity/genetics*

The connection between tendons and bones is called the tendon bone connection. With the continuous improvement of national sports awareness, excessive exercises and the related intensity are prone to damage the tendon bone connection. Tendon bone healing is a complex repair and healing process involving multiple factors, and good tendon bone healing is a prerequisite for its physiological function. The complexity of tendon bone structure also poses great challenges to the repair of tendon bone injuries. In recent years, researches have found that stem cells, growth factors, macrophages, and other factors are closely related to the healing process of tendon bone injuries, among which macrophages play an important role in the healing process. The authors reviewed relevant research literature in recent years and summarized the role of macrophages in tendon bone healing, in order to provide new ideas and directions for treatment strategies to promote tendon bone healing.
Humans ; Macrophages/metabolism* ; Wound Healing ; Animals ; Tendons/physiology* ; Bone and Bones/injuries* ; Tendon Injuries

Objective To explore the effects of miR-373 and Janus kinase 2/signal transducer and activator of transcription 6 (JAK2/STAT6) signaling pathways on the M2 polarization of tumor associated macrophages (TAM) in rectal cancer. Methods THP-1 cells were induced into M0/M1/M2 macrophages, M0 macrophages were cocultured with Caco-2 cells to obtain TAM, Flow cytometry was used to detect the expression of CD86 and CD206, Real-time quantitative qPCR and Western blot were used to detect miR-373, inducible nitric oxide synthase (iNOS), toll-like receptor 4 (TLR-4), interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), arginase 1 (Arg1), chitinase 3-like 1 (Ym1), resistin like α (Fizz1), IL-10 mRNA and protein levels. TAM were transfected and divided into overexpressing miR-373 group (miR-373-TAM) and control group (miR-NC-TAM), overexpressing miR-373+JAK2-TAM group (miR-373 combined with JAK2-TAM) and control group (miR-373 combined with NC-TAM), and then cocultured with Caco-2 cells. Flow cytometry was used to detect the expression of CD206 in TAM; Real-time quantitative PCR and Western blot were used to detect miR-373, Arg1, Ym1, Fizz1, IL-10, JAK2, STAT6 mRNA and protein levels in TAM; CCK-8 assay, colony formation assay, and Transwell assay were used to detect the proliferation, migration, and invasion ability of Caco-2 cells. Thirty nude mice were randomly divided into Caco-2 cells group, Caco-2 cells combined with miR-NC-TAM group, and Caco-2 cells combined with miR-373-TAM group, with 10 mice in each group. Rats in each group were subcutaneously injected with pure Caco-2 cells, Caco-2 cells combined with TAM, and Caco-2 cells combined with TAM overexpressing miR-373. After 4 weeks of cell inoculation, immunofluorescence staining was used to detect F4/80⁺CD206⁺cells level in tumor tissue; Real-time quantitative PCR and Western blot were used to detect miR-373, JAK2, STAT6, Arg1, Ym1, Fizz1, IL-10 mRNA and protein levels in tumor tissues. Results TAM tended to M2 polarization. After overexpression of miR-373, miR-373 level in TAM was increased, while Arg1, Ym1, Fizz1, IL-10, JAK2, STAT6 mRNA and protein levels were decreased, proliferation, migration, invasion ability of Caco-2 cells were decreased; Overexpression of JAK2 could partially reverse the effect of overexpression of miR-373 on the M2 polarization of TAM and proliferation, migration, invasion ability of Caco-2 cells. TAM could promote tumor growth; Overexpression of miR-373 could inhibit tumor growth and inhibit M2 polarization of TAM. Conclusion miR-373 could inhibit M2 polarization of TAM in rectal cancer, and miR-373 might inhibit proliferation and metastasis of rectal cancer cells by regulating the JAK2/STAT6 pathway.
MicroRNAs/metabolism* ; Humans ; STAT6 Transcription Factor/genetics* ; Signal Transduction/genetics* ; Animals ; Janus Kinase 2/genetics* ; Mice ; Tumor-Associated Macrophages/metabolism* ; Rectal Neoplasms/pathology* ; Caco-2 Cells ; Mice, Nude ; THP-1 Cells ; Mice, Inbred BALB C ; Cell Polarity ; Male

Objective To investigate the impact of Astragaloside-IV (AS-IV) on the progression of myocardial infarction (MI) through macrophage-dependent mechanisms by regulating Snail1 lactylation and acetylation, as well as the transforming growth factor β (TGF-β) pathway. Methods Oxygen glucose deprivation (OGD) was used to establish an in vitro myocardial ischemia model in rat cardiomyocytes (H9c2), which were then treated with AS-IV. Cell viability was assessed using CCK-8, apoptosis was evaluated by flow cytometry, and LDH levels were measured to assess cellular damage. RAW246.7 cells were treated with LPS, and lactate levels in the supernatant were measured using ELISA, while expression of macrophage phenotype markers was evaluated using Western blot. RAW246.7 cell-conditioned medium (CM) was co-cultured with H9c2 cells to assess the protective effects of AS-IV on macrophage CM-mediated H9c2 damage. RAW246.7 cells were induced to differentiate into M1-like macrophages using LPS (100 ng/mL) + IFN-γ (20 ng/mL), and Snail1 was overexpressed in M1 macrophages. Transfected M1 macrophage CM was co-cultured with H9c2 cells to validate the mechanisms of AS-IV in MI. An MI rat model was established by ligation of the left anterior descending coronary artery (LAD), and was treated with AS-IV. Cardiac function, myocardial cell apoptosis, and cardiac tissue pathology were studied using echocardiography, TUNEL, and HE staining, respectively. Results Compared to the OGD group, AS-IV treatment promoted cell viability, reduced apoptosis and decreased LDH release. LPS upregulated lactate levels in the supernatant of RAW246.7 cell cultures and induced polarization of RAW246.7 cells to the M1 phenotype. AS-IV attenuated the damaging effects of RAW246.7 cell CM on H9c2 cells . Overexpression of Snail1 in M1 macrophages weakened the protective effects of AS-IV on H9c2 cells . In vivo study, results showed that, compared to the MI group, AS-IV treatment reduced lactate levels in the hearts of MI rats, improved cardiac function and myocardial injury and attenuated myocardial cell apoptosis. Conclusion AS-IV inhibits TGF-β pathway activation through the suppression of Snail1 lactylation and acetylation in a macrophage-dependent manner, thereby mitigating myocardial cell damage following MI.
Animals ; Myocardial Infarction/drug therapy* ; Rats ; Snail Family Transcription Factors/metabolism* ; Macrophages/cytology* ; Myocytes, Cardiac/metabolism* ; Triterpenes/pharmacology* ; Saponins/pharmacology* ; Acetylation/drug effects* ; Apoptosis/drug effects* ; Mice ; Cell Line ; RAW 264.7 Cells ; Transforming Growth Factor beta/metabolism*

Objective To explore the effect of miR-582-5p on Mycobacterium tuberculosis (Mtb)-infected macrophages by regulating dual specificity phosphatase 1 (DUSP1). Methods THP-1 macrophages were divided into six groups: control group, Mtb group, inhibitor-NC group, miR-582-5p inhibitor group, miR-582-5p inhibitor+si-NC group, and miR-582-5p inhibitor+si-DUSP1 group. QRT-PCR was applied to detect the gene expression of miR-582-5p and DUSP1 in cells. ELISA kit was used to detect the levels of interferon γ (IFN-γ), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and interleukin 1β (IL-1β). CCK-8 method was applied to detect cell proliferation. Flow cytometry was applied to detect cell apoptosis rate. Western blot analysis was used to measure the protein expression levels of B-cell lymphoma 2 (Bcl2), Bcl2-associated X (BAX), and cleaved-caspase 3 (c-caspase-3) in cells. In addition, the target relationship between miR-582-5p and DUSP1 was verified. Results Compared with the control group, the expression of miR-582-5p, levels of IFN-γ, IL-6, TNF-α, IL-1β, bacterial load and OD450 values (24 h, 48 h), and the protein expression of Bcl2 in macrophages were higher in the Mtb group, while the mRNA expression of DUSP1, apoptosis rate, and the protein expression levels of c-caspase-3, BAX and DUSP1 were lower. Compared with the Mtb group and the inhibitor-NC group, the above-mentioned indicators in the miR-582-5p inhibitor group were partially reversed. Down-regulation of DUSP1 expression partially reversed the inhibitory effect of down-regulation of miR-582-5p expression on Mtb-infected macrophages. Conclusion Inhibiting the expression of miR-582-5p can up-regulate DUSP1, thereby inhibiting the proliferation and inflammatory response of Mtb-infected macrophages and promoting cell apoptosis.
Humans ; Macrophages/metabolism* ; Dual Specificity Phosphatase 1/metabolism* ; MicroRNAs/metabolism* ; Mycobacterium tuberculosis/physiology* ; Tuberculosis/microbiology* ; Apoptosis/genetics* ; THP-1 Cells ; Cell Proliferation/genetics* ; Interferon-gamma/genetics* ; Tumor Necrosis Factor-alpha/genetics* ; Interleukin-1beta/genetics*