BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

ObjectiveTo investigate the possible mechanism of Jishe Qushi Capsule （脊蛇祛湿胶囊， JQC） in treating rheumatoid arthritis （RA） from the perspective of macrophage polarization mediated by neutrophil extracellular traps （NETs）. MethodsTwenty-four female SD rats were randomly divided into four groups， blank control group， model group， JQC group， and peptidylarginine deiminase 4 （PAD4） inhibitor group with 6 rats in each group. All groups but the blank control group were subjected to the induction of collagen-induced arthritis （CIA）. After successful model establishment， rats in the JQC group received intragastric administration of JQC 1.47 g/kg daily； rats in the PAD4 inhibitor group received intraperitoneal injections of the PAD4 inhibitor 4 mg/kg weekly. Rats in the blank， model， and PAD4 inhibitor groups received 2 ml of pure water daily by gavage. All treatments lasted 4 weeks. Joint lesions of each group were assessed on day 7， 14， 21， 28， and 35 after model establishment， and arthritis index （AI） scores were recorded. At 24 h after the final administration， histopathology of knee joints， including HE staining， safranin O-fast green staining， and TRAP staining， was performed. Flow cytometry was used to detect the counts of M1 and M2 macrophages in peripheral blood. ELISA was used to determine serum levels of TRACP， NETs， TNF-α， IL-1β， and iNOS. Western Blotting and qRT-PCR were used to measure MPO， NE， RANKL， OPG， and p65 protein and mRNA expression in knee cartilage tissue. ResultsCompared with the blank control group， the model group showed increased AI scores （P＜0.05）， marked synovial inflammatory infiltration， angiogenesis， and bone-cartilage destruction， increased TRAP-positive osteoclasts， increased M1 macrophages and decreased M2 macrophages， elevated serum TRACP， NETs， TNF-α， IL-1β， and iNOS （P＜0.05）， elevated MPO， NE， RANKL， and p65 protein/mRNA expression and decreased OPG protein/mRNA expression in knee cartilage tissue （P＜0.05）. Compared with the model group， the JQC group exhibited improved synovial inflammation， angiogenesis， and bone-cartilage damage， reduced AI scores on day 21， 28， and 35， decreased osteoclast counts， decreased M1 macrophages and increased M2 macrophages， reduced serum TRACP， NETs， TNF-α， IL-1β， and iNOS （P＜0.05）， decreased MPO， NE， RANKL， and p65 protein/mRNA expression and increased OPG expression （P＜0.05）. Compared with the PAD4 inhibitor group， the JQC group showed significantly lower AI scores， reduced M1 macrophages， increased M2 macrophages （P＜0.05）， reduced serum TRACP， TNF-α， IL-1β， and iNOS， decreased MPO， RANKL， and p65 expression， and increased OPG levels （P＜0.05）. ConclusionThe therapeutic mechanism of JQC for RA may involve inhibition of NETs formation， downregulation of the RANKL/NF-κB signaling pathway， and regulation of macrophage M1/M2 polarization imbalance， thereby suppressing osteoclastogenesis and inflammatory bone destruction.

ObjectiveThis study aims to investigate the action mechanism by which Xiaozheng Zhitong paste （XZP） alleviates bone cancer pain （BCP） by regulating programmed death protein 1 （PD-1）/programmed death-ligand 1 （PD-L1） pathway-induced osteoclast formation. MethodsThirty female C57BL/6 mice were randomly allocated into the following groups （n=6 per group）： normal control group， model group， low‑dose XZP group （31.5 g·kg^-1）， high‑dose XZP group （63 g·kg^-1）， and PD‑1 inhibitor （Niv） group. A bone cancer pain （BCP） model was established by injecting Lewis lung carcinoma cells. Mice in the normal control and model groups received topical application of a blank paste matrix at the wound site. Mice in the low‑ and high‑dose XZP groups were treated with XZP applied topically twice daily. Mice in the Niv group were topically administered the blank paste matrix and additionally received Niv via tail‑vein injection every two days. All interventions were continued for 21 days. During this period， behavioral tests were performed to assess mechanical， motor， and thermal nociceptive sensitivities. After 21 days， all mice were euthanized， and bone tissue from the operated side was collected for sectioning and preservation. Tartrate‑resistant acid phosphatase （TRAP） staining was used to evaluate osteoclast expression in the lesioned bone tissue. Immunohistochemistry was performed to detect the expression of Runt‑related transcription factor 2 （Runx2） in the lesioned bone tissue. Immunofluorescence was employed to assess the expression of PD‑1 and PD‑L1 in the lesioned bone tissue. ResultsCompared with the normal group， the model group showed significantly decreased limb mechanical withdrawal threshold， spontaneous paw flinching， and thermal withdrawal latency （P<0.01）， increased number of osteoclasts in the lesioned bone tissue （P<0.01）， and reduced expression of Runx2 （P<0.01）. Compared with the model group， the BCP mice in the XZP low-dose group， XZP high-dose group， and Niv group exhibited increased limb mechanical withdrawal threshold， movement scores， and thermal withdrawal latency （P<0.01）. The XZP low-dose group showed no significant changes in osteoclast number or Runx2 expression， while the XZP high-dose group and Niv group demonstrated significantly reduced osteoclast numbers （P<0.01） and significantly increased Runx2 expression （P<0.01）. In the lesioned bone tissue of BCP mice， the XZP low-dose group showed no significant decrease in the percentage of PD-1 expression， but a decrease in the percentage of PD-L1 expression （P<0.05）. In contrast， both the XZP high-dose group and the Niv group exhibited significant reductions in the percentages of PD-1 and PD-L1 expression （P<0.01）. ConclusionXZP alleviates the pain of mice with BCP by blocking the PD-1/PD-L1 pathway to inhibit osteoclastogenesis.

ObjectiveThe paper aims to investigate the mechanism by which Xiaozheng Zhitong paste （XZP） alleviates bone cancer pain （BCP） through regulating the PTEN-induced putative kinase 1 （PINK1）/Parkin-mediated mitophagy-NOD-like receptor protein 3 （NLRP3） inflammasome pathway to suppress microglial pyroptosis. MethodsLipopolysaccharide （LPS） and LPS-adenosine triphosphate （ATP） were used to establish an inflammation and pyroptosis model in microglial cells. The cells were randomly divided into the following groups： control group， LPS group， LPS+low-dose XZP group， LPS+high-dose XZP group， LPS-ATP group， LPS-ATP+low-dose XZP group， LPS-ATP+high-dose XZP group， LPS-ATP+XZP group， and LPS-ATP+XZP+CsA group. Techniques including terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling （TUNEL） staining， enzyme-linked immunosorbent assay （ELISA）， Western blot， and confocal fluorescence staining were employed to assess the effects of XZP on microglial apoptosis， inflammatory cytokine release， inflammasome activation， pyroptosis， and mitophagy. ResultsIn vitro experiments showed that compared with the blank group， the LPS group exhibited significantly increased levels of microglial apoptosis and pro-inflammatory factors interleukin （IL）-1β， IL-6， and tumor necrosis factor-α （TNF-α）（P<0.01）， along with significantly upregulated protein expression of inducible nitric oxide synthase （iNOS）， cyclooxygenase-2 （COX-2）， and phosphorylated nuclear factor-κB p65 （p-NF-κB p65） （P<0.01）. Compared with the LPS group， the high-dose LPS-XZP group significantly reduced the level of apoptosis （P<0.01） and the content of the aforementioned pro-inflammatory factors （P<0.01）. Both the low- and high-dose LPS-XZP groups dose-dependently downregulated the protein expression of iNOS， COX-2， and p-NF-κB p65 （P<0.05， P<0.01）. Compared with the blank group， the LPS-ATP group showed significantly upregulated expression of pyroptosis-related proteins， including Caspase-1/pro-Caspase-1， N-terminal fragment of gasdermin D （GSDMD-N）/full-length gasdermin D （GSDMD-F）， NLRP3， apoptosis-associated speck-like protein containing a CARD （ASC）， IL-1β precursor （pro-IL-1β）， and mature IL-1β （P<0.01）. The levels of pyroptotic factors IL-1β and IL-18 were significantly elevated （P<0.01）， and membrane pore formation and intracellular reactive oxygen species （ROS） levels were significantly increased （P<0.01）. Compared with the LPS-ATP group， both the low- and high-dose LPS-ATP+XZP groups dose-dependently downregulated the expression of the aforementioned pyroptosis-related proteins （P<0.05， P<0.01）. The low-dose LPS-ATP+XZP group reduced IL-1β levels （P<0.01）， while the high-dose group reduced both IL-1β and IL-18 levels （P<0.01） Both the low- and high-dose LPS-ATP+XZP groups dose-dependently reduced membrane pore formation and intracellular ROS production （P<0.01）. Compared with the blank group， the LPS-ATP group showed significantly reduced expression of mitophagy-related proteins PINK1 and Parkin， and a decreased ratio of microtubule-associated protein 1 light chain 3Ⅱ（LC3Ⅱ） to LC3Ⅰ（P<0.01）， while p62 expression was significantly increased （P<0.01）. Mitochondrial ROS levels were significantly enhanced （P<0.01）. Compared with the LPS-ATP group， both the low- and high-dose LPS-ATP+XZP groups dose-dependently reversed the expression of these proteins （P<0.05， P<0.01） and reduced mitochondrial ROS levels （P<0.01）. After treatment with the mitophagy inhibitor cyclosporin A （CsA）， the beneficial effects of XZP on mitochondrial function and its inhibitory effects on pyroptosis-related protein expression were significantly reversed （P<0.05， P<0.01）. ConclusionXZP reduces ROS levels by activating PINK1/Parkin-mediated mitophagy， thereby inhibiting NLRP3 inflammasome activation and microglial pyroptosis， which provides new molecular evidence for the mechanism by which XZP alleviates BCP.

ObjectiveTo investigate the effects and underlying mechanisms of Xiaozheng Zhitong Paste （XZP） on bone cancer pain （BCP）. MethodsThirty female BALB/c mice were randomly divided into five groups： a Sham group， a BCP group， a BCP+low-dose XZP group， a BCP+high-dose XZP group， and a BCP+high-dose XZP + protease-activated receptor 2 （PAR2） agonist GB-110 group. BCP mice model was constructed by injecting Lewis lung carcinoma cells into the femoral cavity of the right leg， which was followed by being treated with XZP for 21 d. After 21 d， the mice were sacrificed. Nissl staining was used to evaluate the survival of spinal cord neurons. Immunofluorescence staining was conducted to localize ionized calcium-binding adapter molecule 1 （Iba1） and neuronal nuclear antigen （NeuN） in spinal cord tissue， thereby assessing microglial activation and neuronal survival. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the levels of interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， transforming growth factor-β （TGF-β）， interleukin-4 （IL-4）， and interleukin-10 （IL-10） in spinal cord tissue. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect mRNA expression levels associated with M1/M2 polarization of microglia. Western blot analysis was performed to examine the expression of proteins related to microglial polarization as well as those involved in the PAR2/nuclear factor kappa B （NF-κB）/NOD-like receptor protein 3 （NLRP3） signaling pathway in the spinal cord. ResultsCompared with the Sham group， the spinal cord neurons were damaged， the number of Nissl-positive spinal cord neurons in the spinal cord tissue was significantly reduced （P<0.01）， and the rate of NeuN-positive cells was significantly decreased （P<0.01）. The spinal cord microglia were activated， the inflammatory level of the spinal cord tissue was enhanced， and Iba1 staining was significantly enhanced （P<0.01）. The levels of IL-1β， TNF-α， IL-6， TGF-β， IL-4 and IL-10 were significantly increased （P<0.01）. The mRNA expressions of IL-1β， TNF-α and inducible nitric oxide synthase （iNOS） were significantly increased （P<0.01）， and the expression of PAR2， NLRP3， ASC and NF-κB p65 proteins in the spinal cord tissue of the BCP mice was significantly enhanced （P<0.01）. Compared with the BCP group， high-dose XZP treatment significantly increased the number of Nissl-positive spinal cord neurons in the BCP mice （P<0.01）， significantly enhanced the rate of NeuN-positive cells in the spinal cord tissue， and significantly weakened Iba1 staining （P<0.01）. In addition， the levels of IL-1β， TNF-α， and IL-6 were significantly decreased， while the levels of TGF-β， IL-4， and IL-10 were significantly increased （P<0.05， P<0.01）. The mRNA expression levels of IL-1β， TNF-α， and iNOS were decreased， whereas those of cluster of differentiation 206 （CD206）， arginase-1 （Arg-1）， and YM1/2 were significantly increased （P<0.05， P<0.01）. Low-dose and high-dose XZP treatment significantly decreased the expression of PAR2， NLRP3， ASC， and NF-κB p65 proteins in the spinal cord tissue （P<0.05， P<0.01）. These effects could all be significantly eliminated by the PAR2 agonist GB-110. ConclusionXZP can mitigate BCP in mice， which may be achieved through blocking the activated PAR2/NF-κB/NLRP3 pathway.

ObjectiveThe paper aims to investigate the action mechanism by which the Xiaozheng Zhitong paste （XZP） relieves bone cancer pain （BCP）. MethodsA model of mice with BCP was established by using Lewis tumor cells. The therapeutic effects of XZP， the ferroptosis inhibitor Ferrostatin-1 （Fer-1）， and the nuclear factor erythroid 2-related factor 2 （Nrf2） inhibitor Brusatol （Bru） on BCP were examined. Mice were randomly divided into the Sham operation group， BCP group， BCP+XZP-L group， BCP+XZP-H group， BCP+Fer-1 group， and BCP+XZP-H+Bru group， with six mice in each group. Pain behavior tests were conducted on the mice to assess pain levels. Colorimetric assays were employed to measure ferroptosis-related factors in serum and spinal cord tissue including Fe， malondialdehyde （MDA）， reactive oxygen species （ROS）， and superoxide dismutase （SOD）. Immunofluorescence staining was used to assess ROS production in spinal cord tissue. Transmission electron microscopy was used to observe the ultrastructure of mitochondria in lumbar spinal cord tissue. Quantitative real-time polymerase chain reaction （Real-time PCR） was employed to detect mRNA expression of Nrf2， heme oxygenase-1 （HO-1）， glutathione peroxidase 4 （GPX4）， and solute carrier family 7 member 11 （SLC7A11） in spinal cord neuron tissue. The protein expression of Nrf2， HO-1， GPX4， and SLC7A11 in spinal cord neurons was measured by Western blot. ResultsCompared with the Sham group， mice in the BCP group exhibited significantly reduced limb usage scores， mechanical foot withdrawal thresholds， and thermal foot withdrawal thresholds （P<0.01）. Serum and lumbar spinal cord tissue levels of Fe， MDA， and reactive oxygen species （ROS） were significantly elevated （P<0.05）， while superoxide dismutase （SOD） levels were significantly decreased （P<0.05）. Lumbar spinal cord mitochondrial structural damage was observed， and mRNA and protein expression of Nrf2， HO-1， GPX4， and SLC7A11 were significantly downregulated （P<0.01）. Compared with the BCP group， both low- and high-dose XZP groups improved the aforementioned pain behavioral indicators （P<0.05，P<0.01）， reduced ferroptosis-related biomarkers including Fe， MDA， and ROS levels （P<0.05）， increased SOD levels （P<0.05，P<0.01）， alleviated mitochondrial damage， and upregulated Nrf2， HO-1， GPX4， SLC7A11 mRNA and protein expression （P<0.05，P<0.01）. The high-dose XZP group exhibited comparable efficacy to Fer-1 in alleviating pain and inhibiting ferroptosis. Following Bru administration， XZP's effects on pain behavioral indicators， regulation of ferroptosis-related markers， mitochondrial structural protection， and activation of the Nrf2/HO-1/GPX4/SLC7A11 pathway were significantly reversed （P<0.05，P<0.01）. ConclusionExternal application of XZP alleviates pain symptoms in BCP mice by activating the Nrf2/HO-1/GPX4/SLC7A11 pathway， thereby inhibiting ferroptosis and neuronal damage in spinal cord neurons.

Cancer pain is one of the most common complications in patients with malignant tumors， severely affecting their quality of life. Its pathogenesis involves complex interactions among the tumor microenvironment， peripheral sensitization， and central sensitization. The tumor microenvironment initiates peripheral pain sensitization by secreting algogenic mediators， activating ion channels and related receptor signaling pathways， driving abnormal osteoclast activation， and mediating neuro-immune crosstalk. Persistent nociceptive input further triggers increased excitability of central neurons， activation of glial cells， and neuroinflammatory cascade reactions， ultimately leading to central pain sensitization. Although traditional opioid drugs can alleviate pain to some extent， they still have many limitations， such as incomplete analgesia， drug tolerance， and adverse reactions. In recent years， traditional Chinese medicine （TCM） compounds have made continuous progress in the treatment of cancer pain. Studies have shown that they can not only effectively relieve cancer pain and reduce the dosage of opioids but also significantly improve patients' quality of life. TCM treatment of cancer pain follows the principle of syndrome differentiation and treatment. Based on this， targeted therapeutic principles have been proposed， including promoting blood circulation， removing stasis， regulating Qi， and unblocking collaterals； tonifying the kidney， replenishing essence， warming Yang， and dispersing cold， activating blood， resolving phlegm， detoxifying， and dispersing nodules， as well as strengthening the body， replenishing deficiency， and harmonizing Qi and blood. Modern research indicates that TCM compounds can exert synergistic effects through multiple pathways， inhibiting inflammatory responses， regulating nerve conduction， intervening in bone metabolism and related gene expression， thereby producing anti-inflammatory and bone-protective effects to achieve the goal of alleviating cancer pain. This article systematically elaborates on the pathogenesis of cancer pain， the clinical application of TCM in treating cancer pain， and its related mechanisms of action， aiming to provide a theoretical basis and new strategies for the integration of TCM into comprehensive cancer pain management.

Pain， as one of the most common symptoms in cancer patients， seriously affects the survival quality of patients. The three-step pain relief program currently used in clinical practice cannot completely relieve pain in cancer patients and is accompanied by many problems. From the perspective of Jueyin syndrome in traditional Chinese medicine （TCM）， this paper believed that the core pathogenesis of cancer pain was declined healthy Qi and cold and heat in complexity， and used Wumeiwan as the main formula with modification according to syndrome for clearing the upper， warming the lower part of the body， and harmonizing the cold and heat. It can regulate the pathological environment of deficiency， cold， stasis， toxicity， and heat， and restore the physiological function of Yang transforming Qi while Yin constituting form， so as to prevent， relieve， and even eliminate cancer pain， having achieved good clinical efficacy. It can not only help cancer patients relieve pain， but also control tumor and eliminate tumor， achieving a dual benefit of pain relief and tumor suppression. It gives full play to the characteristics and advantages of syndrome differentiation and treatment in TCM， and expands the scope of ZHANG Zhongjing's treatment for Jueyin syndrome， which provides ideas for the clinical diagnosis and treatment of cancer pain from the perspective of deficiency-excess in complexity and cold and heat in complexity.

ObjectiveThis paper aims to investigate the mechanism of Jinyang Dingtong plaster in improving the peripheral pain sensitization and synovial fibrosis in rats with knee osteoarthritis （KOA） by blocking the ion channels of transient receptor potentials （TRPs）. MethodsThe active components in the transdermal absorption solution of Jinyang Dingtong plaster were identified by using ultra-high performance liquid chromatography-electrospray ionization-quadrupole ion trap tandem mass spectrometry （UPLC-MS/MS） technology. A KOA rat model was established through intra-articular injection of monoiodoacetic acid. The rats were randomly divided into blank control group， KOA group， compound Nanxing Zhitong plaster Group， and Jinyang Dingtong plaster group， with eight rats per group. Among them， the rats in the compound Nanxing Zhitong plaster group and the Jinyang Dingtong plaster group were intervened with external application treatment. After the intervention period， the cold and mechanical stimulus pain thresholds of rats in each group were detected， and the transverse diameter of the knee joint was measured. The levels of inflammatory factors in the serum such as interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， nerve growth factor （NGF）， and calcitonin gene-related peptide （CGRP） were determined by enzyme-linked immunosorbent assay （ELISA）. Protein expression levels of transient receptor potential ankyrin 1 （TRPA1）， transient receptor potential melastatin 8 （TRPM8）， transient receptor potential vanilloid 1 （TRPV1）， transient receptor potential vanilloid 4 （TRPV4）， transforming growth factor-β （TGF-β）， and vascular endothelial growth factor （VEGF） in synovial tissue were detected by Western blot. Histopathological changes in synovial tissue were observed by using hematoxylin and eosin （HE）， Masson， and Sirius red staining， while the expression of type Ⅰ collagen and alpha-smooth muscle actin （α-SMA） was detected by multiplex immunofluorescence. ResultsA total of 35 active components in the transdermal absorption solution of Jinyang Dingtong plaster were identified by UPLC-MS/MS， including phenolic acids， flavonoids， quinones， alkaloids， terpenes， lignans， and coumarins. Among them， the constituents such as berberine， paeoniflorin， ferulic acid， and caffeic acid exhibit clear anti-inflammatory， analgesic， and anti-fibrotic pharmacological effects. Compared to the blank control group， rats in the KOA group showed a significant decrease in cold and mechanical stimuli pain thresholds （P<0.01）. After 14 and 28 days of Jinyang Dingtong plaster intervention， the pain threshold in this group was significantly increased compared to that in KOA group （P<0.01）， showing no significant difference from that in compound Nanxing Analgesic plaster group. Additionally， Jinyang Dingtong plaster reduced the levels of IL-1β， TNF-α， NGF， and CGRP in the serum of KOA rats （P<0.01）， lowered the expression of TRPA1， TRPM8， TRPV1， TRPV4， TGF-β， and VEGF proteins in synovial tissue （P<0.01）， improved synovial pathological damage in KOA rats， and significantly decreased fluorescence intensity of type Ⅰ collagen and α-SMA （P<0.01）. ConclusionJinyang Dingtong plaster can improve the peripheral pain sensitization and synovial fibrosis in KOA rats by downregulating the expression of ion channels of TRPs and related inflammatory and fibrotic factors.