OBJECTIVES: Neuropathic pain (NP) is one of the most common forms of chronic pain, yet current treatment options are limited in effectiveness. Peripheral nerve injury activates spinal microglia, altering their inflammatory response and phagocytic functions, which contributes to the progression of NP. Most current research on NP focuses on microglial inflammation, with relatively little attention to their phagocytic function. Early growth response factor 2 (EGR2) has been shown to regulate microglial phagocytosis, but its specific role in NP remains unclear. This study aims to investigate how EGR2 modulates microglial phagocytosis and its involvement in NP, with the goal of identifying potential therapeutic targets. METHODS: Adult male Sprague-Dawley (SD) rats were used to establish a chronic constriction injury (CCI) model of the sciatic nerve. Pain behaviors were assessed on days 1, 3, 7, 10, and 14 post-surgery to confirm successful model induction. The temporal and spatial expression of EGR2 in the spinal cord was examined using real-time quantitative PCR (RT-qPCR), Western blotting, and immunofluorescence staining. Adeno-associated virus (AAV) was used to overexpress EGR2 in the spinal cord, and behavioral assessments were performed to evaluate the effects of EGR2 modulation of NP. CCI and lipopolysaccharide (LPS) models were established in animals and microglial cell lines, respectively, and changes in phagocytic activity were measured using RT-qPCR and fluorescent latex bead uptake assays. After confirming the involvement of microglial phagocytosis in NP, AAV was used to overexpress EGR2 in both in vivo and in vitro models, and phagocytic activity was further evaluated. Finally, eukaryotic transcriptome sequencing was conducted to screen differentially expressed mRNAs, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses to identify potential downstream effectors of EGR2. RESULTS: The CCI model successfully induced NP. Following CCI, EGR2 expression in the spinal cord was upregulated in parallel with NP development. Overexpression of EGR2 via spinal AAV injection enhanced microglial phagocytic activity and increased pain hypersensitivity in rats. Both animal and cellular models showed that CCI or LPS stimulation enhanced microglial phagocytosis, which was further amplified by EGR2 overexpression. Transcriptomic analysis of spinal cord tissues from CCI rats overexpressing EGR2 revealed upregulation of numerous genes associated with microglial phagocytosis and pain regulation. Among them, Lag3 emerged as a potential downstream target of EGR2. CONCLUSIONS EGR2 contributes to the maintenance of NP by enhancing microglial phagocytosis in the spinal dorsal horn.
Animals ; Microglia/metabolism* ; Phagocytosis/physiology* ; Rats, Sprague-Dawley ; Neuralgia/physiopathology* ; Early Growth Response Protein 2/metabolism* ; Male ; Rats ; Spinal Cord/metabolism* ; Sciatic Nerve/injuries*

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

OBJECTIVES: To evaluate the effect of eye acupuncture on neural function and angiogenesis of ischemic cerebral tissue in rats, and explore the roles of METTL3-mediated m⁶A methylation and the HIF-1α/VEGF-A signal axis in mediating this effect. METHODS: Fifty SD rats were randomized into normal control group, sham-operated group, model group, eye acupuncture group and DMOG (a HIF-1α agonist) group. Rat models of cerebral ischemia/reperfusion injury (CIRI) were established using a modified thread thrombus method, and the changes in neurological deficits of the rats after interventions were evaluated. TTC and Nissl staining were used to examine the changes in infarction size and neuronal injury, and cerebral angiogenesis was detected by double-immunofluorescence staining. m⁶A methylation modification level in the brain tissue was detected by ELISA, and RT-qPCR and Western blotting were used to detect the mRNA and protein expressions of METTL3 and HIF-1α/VEGF-A. RESULTS: Compared with the control and sham-operated rats, the CIRI rats had significantly higher neurological deficit scores with larger cerebral infarction area, a greater number of CD31- and EDU-positive new vessels, higher expression levels of HIF-1α and VEGF-A, reduced number of Nissl bodies and m6A methylation level, and lowered METTL3 protein and mRNA expressions. All these changes were significantly improved by interventions with eye acupuncture after modeling or intraperitoneal injections of DMOG for 7 consecutive days prior to modeling, and the effects of the two interventions were similar. CONCLUSIONS Eye acupuncture can improve neurological deficits in CIRI rat models possibly by promoting cortical angiogenesis via upregulating METTL3-mediated m⁶A methylation and regulating the HIF-1α/VEGF-A signal axis.
Animals ; Rats, Sprague-Dawley ; Methyltransferases/metabolism* ; Reperfusion Injury/physiopathology* ; Methylation ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Rats ; Vascular Endothelial Growth Factor A/metabolism* ; Brain Ischemia/metabolism* ; Acupuncture Therapy ; Male ; Up-Regulation ; Neovascularization, Physiologic ; Angiogenesis ; Adenosine/analogs & derivatives*

OBJECTIVES: To investigate the effects of Naoluo Xintong Decoction (NLXTD) on proliferation of rat brain microvascular endothelial cells (BMECs) after oxygen-glucose deprivation/reoxygenation (OGD/R) injury and role of the HIF-1α/VEGF pathway in mediating its effect. METHODS: Using a BMEC model of OGD/R, we tested the effects of 10% NLXTD-medicated rat serum, alone or in combination with 2ME2 or 10% NAKL, on cell proliferation, migration, tube-forming ability and permeability using CCK-8 assay, Transwell chamber assay, tube formation assay and permeability assay. Cellular expressions of VEGF and Notch were detected using ELISA and laser confocal immunofluorescence analysis, and the expressions of HIF-1α, VEGFR2, Notch1, ERK and P-ERK1/2 proteins were detected with Western blotting. RESULTS: OGD/R injury significantly decreased viability of BMECs. NLXTD treatment of the cells with OGD/R could significantly promoted cell proliferation, migration and tube formation ability, but these effects were strongly attenuated by application of 2ME2. NLXTD treatment also significantly increased the percentages of VEGF- and Notch-positive cells in the cell models and obviously enhanced the expression levels of HIF-1α, VEGFR2, Notch1 and P-ERK1/2. CONCLUSIONS NLXTD promotes proliferation, migration, and tube formation of rat BMECs after OGD/R injury possibly by activating the HIF-1α/VEGF signaling pathway.
Animals ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Vascular Endothelial Growth Factor A/metabolism* ; Endothelial Cells/metabolism* ; Rats ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects* ; Glucose ; Brain/blood supply* ; Cells, Cultured ; Rats, Sprague-Dawley ; Vascular Endothelial Growth Factor Receptor-2/metabolism* ; Oxygen/metabolism* ; Cell Hypoxia

OBJECTIVES: To explore the promoting effect of ginsenoside Rb3 (Rb3) on osteogenesis in periodontitis environment, and to explain its mechanism. METHODS: Human periodontal ligament stem cells (hPDLSCs) were cultured by tissue block method and identified by flow cytometry. Cell counting kit-8 (CCK8) method and calcein acetoxymethyl ester/propidium iodide staining were used to detect the effect of Rb3 on the viability of hPDLSCs cells. In vitro cell experiments were divided into control group, 10 μg/mL lipopolysaccharides (LPS) group, 10 μg/mL LPS+100 μmol/L Rb3 group and 10 μg/mL LPS+200 μmol/L Rb3 group. Alkaline phosphatase (ALP) staining was used to detect the ALP activity of hPDLSCs in each group after osteogenesis induction. The expression of hPDLSCs interleukin-6 (IL-6), interleukin-8 (IL-8), runt-related transcription factor 2 (RUNX2) and transforming growth factor-β (TGF-β)genes in each group after osteogenesis was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) method. Western blot was used to detect the protein expression of hPDLSCs phosphorrylated extracellular signal-regulated kinase (p-ERK) in each group. Sprague-Dawley rats were randomly divided into the control group, ligation group and ligation+Rb3 group. The left molar-maxillary tissue was subjected to micro-computed tomography (micro-CT) scanning. After the scanning, the left molar-maxilla was made into periodontal tissue sections. Hematoxylin-eosin (HE) staining was used to detect the infiltration and loss of adhesion of inflammatory cells. Masson staining was used to detect the destruction of gingival collagen fibers. Immunofluorescence staining was used to detect the protein expression of RUNX2 and p-ERK. The expression of TGF-β in rat gingival tissue was detected by qRT-PCR. The protein expression of IL-6 in peripheral serum of rats was detected by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to detect the proportion of Treg cells in rat heart blood. The experimental data were statistically analyzed by Graph Pad Prism10.1.2 software. RESULTS: Rb3 had no effect on the cell activity of hPDLSCs. The results of qRT-PCR and ALP staining showed that Rb3 could inhibit the gene expression of IL-6 and IL-8 in inflammatory hPDLSCs, promote TGF-β gene and promote the osteogenic differentiation of inflammatory hPDLSCs. Western blot showed that Rb3 inhibited the protein expression of inflammatory hPDLSCs p-ERK. The results from micro-CT, Masson staining, and HE staining demonstrated that Rb3 promotes alveolar bone formation in rats with periodontitis, while simultaneously inhibiting the destruction of periodontal fibrous tissue, reducing attachment loss, and suppressing inflammatory cell infiltration. The results of flow cytometry showed that Rb3 could promote the differentiation of Treg cells in peripheral blood of periodontitis rats. The results of ELISA and qRT-PCR showed that Rb3 could inhibit the protein expression of IL-6 and promote the gene expression of TGF-β in periodontitis rats. Immunofluorescence results showed that Rb3 could promote the protein expression of RUNX2 and inhibit the protein expression of p-ERK in periodontitis rats. CONCLUSIONS Rb3 can reduce the inflammatory reaction of periodontal tissues in periodontitis rats, and promote the osteogenic differentiation of hPDLSCs by regulating p-ERK pathways.
Animals ; Ginsenosides/pharmacology* ; Osteogenesis/drug effects* ; Periodontitis/metabolism* ; Rats ; Periodontal Ligament/cytology* ; Humans ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Stem Cells/drug effects* ; Interleukin-6/metabolism* ; Rats, Sprague-Dawley ; Interleukin-8/metabolism* ; Cells, Cultured ; MAP Kinase Signaling System/drug effects* ; Transforming Growth Factor beta/metabolism* ; Signal Transduction ; Male ; Phosphorylation ; Lipopolysaccharides ; Extracellular Signal-Regulated MAP Kinases/metabolism* ; Alkaline Phosphatase/metabolism*

OBJECTIVE: To explore the effect and mechanism of acupuncture at "Weizhong" (BL40) on microcirculation of paravertebral skeletal muscle in rats with chronic blunt injury of lumbar muscle based on the insulin-like growth factor-1 (IGF-1)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway. METHODS: Forty-eight SPF-grade SD rats were randomized into a blank group (8 rats) and a modeling group (40 rats). Chronic blunt injury model was established by weight impact method in the modeling group. Forty rats were successfully modeled, and were randomly divided into a model group, an acupuncture at Weizhong group (Weizhong group), an acupuncture at non-acupoint group (non-acupoint group), an inhibitor group, and an inhibitor+acupuncture at Weizhong group (inhibitor+Weizhong group), 8 rats in each group. In the Weizhong group and the inhibitor+Weizhong group, acupuncture was applied at bilateral "Weizhong" (BL40). In the non-acupoint group, acupuncture was applied at non-acupoints, i.e. points 0.5 cm inward from bilateral "Weizhong" (BL40). The acupuncture intervention was delivered 20 min each time, once a day for continuous 2 weeks. In the inhibitor group and the inhibitor+Weizhong group, intraperitoneal injection of IGF-1 receptor (IGF-1R) inhibitor was given once a day, at a dosage of 2 mg/100 g, for continuous 2 weeks. Before modeling and on the 1st, 7th and 14th days of intervention, the body mass was measured. Before and after modeling, and after intervention, the limb grip strength and paw withdrawal threshold (PWT) were measured. After intervention, the morphology of psoas muscle was observed by HE staining; the ultrastructure of psoas muscle capillaries was observed by electron microscopy; the levels of serum vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) were detected by ELISA; and the protein and mRNA expression of IGF-1, IGF-1R, PI3K, AKT of psoas muscle was detected by Western blot and real-time PCR. RESULTS: Compared with the blank group, in the model group, the body mass on the 7th and 14th days of intervention, the limb grip strength, and the PWT of left and right hind feet were decreased (P<0.001, P<0.01); the skeletal muscle cells showed enlarged intercellular space, loosely arranged and irregularly shaped, the capillaries in the psoas muscle tissues were edematous, and the lumen of the blood vessels was obviously atrophied; the levels of serum VEGF and eNOS were decreased (P<0.001); in psoas muscle, the protein expression of IGF-1 and IGF-1R, as well as the p-PI3K/PI3K, p-AKT/AKT values were decreased (P<0.001), the mRNA expression of IGF-1, IGF-1R, PI3K and AKT was decreased (P<0.001, P<0.05). Compared with the model group, in the Weizhong group, the body weight was increased on the 7th and 14th days of intervention (P<0.001), the limb grip strength and the PWT of the left and right hind feet were increased (P<0.001, P<0.01); the arrangement of the skeletal muscle cells was relatively tight and the intercellular space was reduced, the blood vessels tended to be regular and the structure of the basement membrane was continuous, while the lumens of blood vessels were collapsed locally; the levels of serum VEGF and eNOS were increased (P<0.001); in psoas muscle, the protein expression of IGF-1 and IGF-1R, as well as the p-PI3K/PI3K, p-AKT/AKT values were increased (P<0.001), the mRNA expression of IGF-1, IGF-1R, PI3K and AKT was increased (P<0.001, P<0.01). Compared with the model group, in the inhibitor group, the body mass was decreased on the 7th and 14th days of intervention (P<0.05, P<0.01); the limb grip strength and the PWT of the left hind foot were decreased (P<0.01, P<0.001); the intercellular space of skeletal muscle cells was larger, the nuclei of the cells and erythrocytes were scattered in the intercellular space, the damage of the capillaries in the muscular tissues was serious, the collagen fibers were sparsely distributed and disorganized; the levels of serum VEGF and eNOS were decreased (P<0.001, P<0.01); in psoas muscle, the protein expression of IGF-1 and IGF-1R, as well as the p-PI3K/PI3K and p-AKT/AKT values were decreased (P<0.01, P<0.05, P<0.001), the mRNA expression of IGF-1, IGF-1R, PI3K, and AKT was decreased (P<0.01, P<0.001, P<0.05). Compared with the Weizhong group, in the non-acupoint group and the inhibitor+Weizhong group, the body mass was decreased on the 7th and 14th days of intervention (P<0.001, P<0.01), the limb grip strength was decreased (P<0.001); the morphology of muscle cell was relatively poor, with generally irregular, there was mild collapse and atrophy in the vascular lumen, and mild edema in the endothelial cells; the levels of serum VEGF and eNOS were decreased (P<0.001); in psoas muscle, the protein expression of IGF-1 and IGF-1R, as well as the p-PI3K/PI3K and p-AKT/AKT values were decreased (P<0.01, P<0.001), the mRNA expression of IGF-1, IGF-1R, PI3K, and AKT was decreased (P<0.001, P<0.01, P<0.05). Compared with the Weizhong group, the PWT of the left hind foot was decreased in the non-acupoint group (P<0.001), and PWT of the left and right hind feet was decreased in the inhibitor+Weizhong group (P<0.001). CONCLUSION Acupuncture at "Weizhong" (BL40) promotes lumbar muscle repair in chronic low back pain, its mechanism may be related to the activation of the IGF-1/PI3K/AKT pathway, thereby improving the microcirculation.
Animals ; Insulin-Like Growth Factor I/genetics* ; Acupuncture Therapy ; Rats, Sprague-Dawley ; Rats ; Proto-Oncogene Proteins c-akt/genetics* ; Male ; Humans ; Muscle, Skeletal/metabolism* ; Signal Transduction ; Phosphatidylinositol 3-Kinases/genetics* ; Wounds, Nonpenetrating/metabolism* ; Acupuncture Points

Intrauterine adhesion(IUA) is a common gynecological disease that is difficult to treat, and there is a lack of specific effective drugs and measures to prevent endometrial fibrosis. In this study, the mechanism of endometrial oxidative stress and fibrosis regulation was studied in an IUA rat model constructed by Bushen Huoxue Formula intervention of mechanical injury combined with infection. A total of 72 SPF SD female rats aged 8-10 weeks were randomly divided into blank control group, model control group, low-dose, medium-dose, and high-dose groups of Bushen Huoxue Formula, and estrogen groups. The rats in the estrous cycle of the model control group and the positive control group were simulated with surgical injury and infection, and the sham operation group was treated with on-off abdominal treatment. After successful modeling, the model control group was administered intragastrically with purified water of 15 μL·g~(-1) every day. The low-dose group was administered intragastrically with Bushen Huoxue Formula of 7.8 g·kg~(-1); the medium-dose group was administered intragastrically with Bushen Huoxue Formula of 15.6 g·kg~(-1), and the high-dose group was administered intragastrically with Bushen Huoxue Formula of 31.2 g·kg~(-1). The estrogen group was administered intragastrically with estradiol valerate of 4.2 mg·kg~(-1). After continuous intervention for 28 days, all rats were deprived of water and killed to collect blood and tissue. Hematoxylin-eosin(HE) staining calculated the number of uterine glands; Masson staining calculated the area of uterine collagen fibers. Combined with HE and Masson staining, semi-quantitative scores were performed on the degree of endometrial fibrosis. Immunohistochemistry was performed to detect the vascular endothelial growth factor(VEGF), stromal cell-derived factor-1(SDF-1), and transforming growth factor-β1(TGF-β1) expression in rats' uterine tissue. Enzyme-linked immunosorbent assay(ELISA) dected angiopoietin 1(IFN-γ), interleukin-1α(IL-1α), TGF-β1, tumor necrosis factor-α(TNF-α), collagen type Ⅳ(Ⅳ-Col), leukemia inhibitory factor(LIF), superoxide dismutase(SOD)、glutathione peroxidase(GSH-Px);The mRNA expressions of Smad2, Smad3, adisintegrin and metalloproteinase(ADAM17) and TGF-β1 were determined by qPCR. Notch and ADAM17 protein expression in rat uterus were determined by Western blot. The results showed that the area of uterine fibrosis was significantly reduced and the conditions of edema and adhesion were effectively alleviated after high-dose intervention of Bushen Huoxue Formula. The levels of inflammatory factors and Ⅳ-Col were significantly decreased, and the levels of LIF and antioxidant enzymes were significantly increased. The mRNA expressions of Smad2, Smad3, ADAM17 and TGF-β1 were significantly down-regulated. Immunohistochemical results showed that Bushen Huoxu Formula could effectively increase the positive expression of SDF-1 and reduce the positive expression of VEGF and TGF-β1. Western blot results showed that the protein expressions of Notch and ADAM17 in high-dose, medium-dose and low-dose of Bushen Huoxu Formula groups were significantly down-regulated in a dose-dependent manner. These results suggest that Bushen Huoxue Formula may inhibit fibrosis process through ADAM17/Notch signaling pathway, suggesting that Bushen Huoxuet Formula is one of the potential therapeutic methods for IUA.
Animals ; Female ; Drugs, Chinese Herbal/administration & dosage* ; Rats, Sprague-Dawley ; Endometrium/pathology* ; Rats ; Fibrosis/metabolism* ; Oxidative Stress/drug effects* ; Humans ; Uterine Diseases/genetics* ; Vascular Endothelial Growth Factor A/genetics*

This study aims to explore whether Naoxintong Capsules improve multiple cerebral infarctions and myocardial injury via promoting angiogenesis, thereby exerting a simultaneous treatment effect on both the brain and heart. Male SD rats were randomly divided into six groups: sham-operated group, model group, high-dose, medium-dose, and low-dose groups of Naoxintong Capsules(440, 220, and 110 mg·kg~(-1)), and nimodipine group(10.8 mg·kg~(-1)). Rat models of multiple cerebral infarctions were established by injecting autologous thrombus, and samples were collected and tested seven days after modeling. Evaluations included multiple cerebral infarction model assessments, neurological function scores, grip strength tests, and rotarod tests, so as to evaluate neuromotor functions. Morphological structures of brain and heart tissue were observed using hematoxylin-eosin(HE) staining, Nissl staining, and Masson staining. Network pharmacology was employed to screen the mechanisms of Naoxintong Capsules in improving multiple cerebral infarctions and myocardial injury. Neuronal and myocardial cell ultrastructures were observed using transmission electron microscopy. Apoptosis rate in brain neuronal cells was detected by TdT-mediated dUTP nick end labeling(TUNEL) staining, and reactive oxygen species(ROS) levels in myocardial cells were measured. Immunofluorescence was used to detect the expression of platelet endothelial cell adhesion molecule-1(CD31), antigen identified by monoclonal antibody Ki67(Ki67), hematopoietic progenitor cell antigen CD34(CD34), and hypoxia inducible factor-1α(HIF-1α) in brain and myocardial tissue. Western blot, and real-time quantitative polymerase chain reaction(RT-qPCR) were used to detect the expression of HIF-1α, vascular endothelial growth factor(VEGF), vascular endothelial growth factor receptor 2(VEGFR2), sarcoma(Src), basic fibroblast growth factor(bFGF), angiopoietin-1(Ang-1), and TEK receptor tyrosine kinase(Tie-2). Compared with the model group, the medium-dose group of Naoxintong Capsules showed significantly lower neurological function scores, increased grip strength, and prolonged time on the rotarod. Pathological damage in brain and heart tissue was reduced, with increased and more orderly arranged mitochondria in neurons and cardiomyocytes. Apoptosis in brain neuronal cells was decreased, and ROS levels in cardiomyocytes were reduced. The microvascular density and endothelial cells of new blood vessels in brain and heart tissue increased, with increased overlapping regions of CD31 and Ki67 expression. The relative protein and mRNA expression levels of HIF-1α, VEGF, VEGFR2, Src, Ang-1, Tie-2, and bFGF were elevated in brain tissue and myocardial tissue. Naoxintong Capsules may improve multiple cerebral infarctions and myocardial injury by mediating HIF-1α/VEGF expression to promote angiogenesis.
Animals ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Rats, Sprague-Dawley ; Rats ; Cerebral Infarction/genetics* ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; Vascular Endothelial Growth Factor A/genetics* ; Capsules ; Signal Transduction/drug effects* ; Humans ; Brain/metabolism* ; Myocardium/metabolism* ; Apoptosis/drug effects*

This study aimed to explore the effects and mechanisms of total extracts from Anthriscus sylvestris on pulmonary hypertension in rats. Sixty male SD rats were divided into normal(NC) group, model(M) group, positive drug sildenafil(Y) group, low-dose A. sylvestris(ES-L) group, medium-dose A. sylvestris(ES-M) group, and high-dose A. sylvestris(ES-H) group. On day 1, rats were intraperitoneally injected with monocrotaline(60 mg·kg~(-1)) to induce pulmonary hypertension, and the rat model was established on day 28. From days 15 to 28, intragastric administration of the respective treatments was performed. After modeling and treatment, small animal echocardiography was used to detect the right heart function of the rats. Arterial blood gas was measured using a blood gas analyzer. Hematoxylin and eosin(HE) staining and Masson staining were performed to observe cardiopulmonary pathological damage. Flow cytometry was used to detect apoptosis in the lung and myocardial tissues and reactive oxygen species(ROS) levels. Western blot was applied to detect the expression levels of transforming growth factor-β1(TGF-β1), phosphorylated mothers against decapentaplegic homolog 3(p-Smad3), Smad3, tissue plasminogen activator(t-PA), and plasminogen activator inhibitor-1(PAI-1) in lung tissue. A blood routine analyzer was used to measure inflammatory immune cell levels in the blood. Enzyme-linked immunosorbent assay(ELISA) was used to detect the expression levels of P-selectin and thromboxane A2(TXA2) in plasma. The results showed that, compared with the NC group, right heart hypertrophy index, right ventricular free wall thickness, right heart internal diameter, partial carbon dioxide pressure(PaCO_2), apoptosis in cardiopulmonary tissue, and ROS levels were significantly increased in the M group. In contrast, the ratio of pulmonary blood flow acceleration time(PAT)/ejection time(PET), right cardiac output, change rate of right ventricular systolic area, systolic displacement of the tricuspid ring, oxygen partial pressure(PaO_2), and blood oxygen saturation(SaO_2) were significantly decreased in the M group. After administration of the total extract of A. sylvestris, right heart function and blood gas levels were significantly improved, while apoptosis in cardiopulmonary tissue and ROS levels significantly decreased. Further testing revealed that the total extract of A. sylvestris significantly decreased the levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and PAI-1 proteins in lung tissue, while increasing the expression of t-PA. Additionally, the extract reduced the levels of inflammatory cells such as leukocytes, lymphocytes, granulocytes, and monocytes in the blood, as well as the levels of P-selectin and TXA2 in plasma. Metabolomics results showed that the total extract of A. sylvestris significantly affected metabolic pathways, including arginine biosynthesis, tyrosine metabolism, and taurine and hypotaurine metabolism. In conclusion, the total extract of A. sylvestris may exert an anti-pulmonary hypertension effect by inhibiting the TGF-β1/Smad3 signaling pathway, thereby alleviating immune-inflammatory responses and thrombosis.
Animals ; Male ; Smad3 Protein/metabolism* ; Transforming Growth Factor beta1/metabolism* ; Rats, Sprague-Dawley ; Rats ; Signal Transduction/drug effects* ; Hypertension, Pulmonary/genetics* ; Thrombosis/immunology* ; Drugs, Chinese Herbal/administration & dosage* ; Humans ; Apoptosis/drug effects*

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*