OBJECTIVE: To analyze the influences of dihydromyricetin on the proliferation and apoptosis of chondrocytes in osteoarthritis induced by hydrogen peroxide (H₂O₂) through reactive oxygen species (ROS)/p38 mitogen activated protein kinase (p38-MAPK) pathway. METHODS: Five C57BL/6J mice were euthanized by cervical dislocation after anesthesia. Chondrocytes were extracted and cultured.After passage, the chondrocytes were divided into control group, H2O2 group (0.8 μmol·L^-1 H₂O₂), dihydromyricetin low concentration group (0.8 μmol·L^-1 H₂O₂+20 μmol·L^-1 dihydromyricetin), dihydromyricetin high concentration group (0.8 μmol·L^-1 H₂O₂+80 μmol·L^-1 dihydromyricetin), and ROS inhibitor N-acetylcysteine (NAC) group (0.8 μmol·L^-1 H₂O₂+5 mmol·L^-1 NAC). The activity of chondrocytes was measured by methyl thiazolyl tetrazolium (MTT) assay. The apoptosis rate of chondrocytes was measured by Hoechst 33342 method. The level of ROS in chondrocytes was measured by 2, 7-dichlorofluorescein diacetate (DCFH-DA) fluorescence probe.The level of Type II collagen α1 (Col2α1) mRNA was measured by qRT-PCR.And the expression of Col2α1, p-p38-MAPK/p38-MAPK, B cell lymphoma gene-2 (Bcl-2) and Bcl-2 associated X protein (Bax) proteins was detected by Western blot. RESULTS: The chondrocytes showed swirling fibrous mass, and the expression of COL2α was positive. Compared with the control group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in H2O22 group increased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins decreased (P<0.05). Compared with H₂O₂ group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in dihydromyricetin low concentration group, dihydromyricetin high concentration group, and NAC group decreased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins increased (P<0.05). CONCLUSION Dihydromyricetin may inhibit chondrocyte apoptosis, inflammatory reaction and oxidative stress by inhibiting ROS/p38-MAPK pathway. Dihydromyricetin may be a potential drug for treating osteoarthritis.
Animals ; Chondrocytes/metabolism* ; Apoptosis/drug effects* ; Hydrogen Peroxide/toxicity* ; Osteoarthritis/physiopathology* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism* ; Mice ; Flavonols/pharmacology* ; p38 Mitogen-Activated Protein Kinases/genetics* ; Cell Proliferation/drug effects* ; Male ; Signal Transduction/drug effects* ; MAP Kinase Signaling System/drug effects* ; Cells, Cultured

Objective The aim of this study was to investigate the effect of p38 on stem cell maintenance of pancreatic cancer. Methods Human pancreatic cancer cells PANC-1 were treated with different concentrations of 5-fluorouracil(5-FU)(0.5×IC₅₀, IC₅₀, and 2×IC₅₀) for 24 hours, and VX-702 (p38 phosphorylation inhibitor) was added, and the cells were inoculated in 6-well culture dishes with ultra-low adhesion to observe the changes of sphere tumors. The expression levels of cyclin-dependent kinase 2(CDK2), cyclin B1 and D1, Octamer-binding transcription factor 4(OCT4), SRY-box transcription factor 2(SOX2), Nanog and p38 were measured by Western blot. The mRNA expression levels of p38, OCT4, Nanog and SOX2 were tested by RT-PCR. Cell cycle, apoptosis, and the proportion of CD44⁺CD133⁺PANC-1 cells were evaluated by flow cytometry. Results The results showed that 5-FU inhibited the formation of tumor spheres in PANC-1 cells, increased CD44⁺CD133⁺cell fragments, down-regulated the expression of OCT4, Nanog and SOX2, and inhibited the stemness maintenance of PANC-1 tumor stem cells. Phosphorylation of PANC-1 cells was inhibited by a highly selective p38 MAPK inhibitor, VX-702(p38 mitogen-activated protein kinase inhibitor), which had the same effect as 5-FU treatment. When VX-702 combined with 5-FU was used to treat PANC-1 cells, the therapeutic effect was enhanced. Conclusion p38 inhibitors decreased PANC-1 cell activity and increased cell apoptosis. p38 inhibitors inhibit the stemness maintenance of pancreatic cancer stem cells.
Humans ; Phosphorylation/drug effects* ; Cell Line, Tumor ; p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors* ; Neoplastic Stem Cells/metabolism* ; Drug Resistance, Neoplasm/drug effects* ; Fluorouracil/pharmacology* ; Pancreatic Neoplasms/pathology* ; Apoptosis/drug effects* ; SOXB1 Transcription Factors/genetics* ; Octamer Transcription Factor-3/genetics*

OBJECTIVES: To investigate the effect of interferon-λ1 (IFN-λ1) on glucocorticoid (GC) resistance in human bronchial epithelial cells (HBECs) stimulated by respiratory syncytial virus (RSV). METHODS: HBECs were divided into five groups: control, dexamethasone, IFN-λ1, RSV, and RSV+IFN-λ1. CCK-8 assay was used to measure the effect of different concentrations of IFN-λ1 on the viability of HBECs, and the sensitivity of HBECs to dexamethasone was measured in each group. Quantitative real-time PCR was used to measure the mRNA expression levels of p38 mitogen-activated protein kinase (p38 MAPK), glucocorticoid receptor (GR), and MAPK phosphatase-1 (MKP-1). Western blot was used to measure the protein expression level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic ratio of GR was calculated. RESULTS: At 24 and 72 hours, the proliferation activity of HBECs increased with the increase in IFN-λ1 concentration in a dose- and time-dependent manner (P˂0.05). Compared with the RSV group, the RSV+IFN-λ1 group had significant reductions in the half-maximal inhibitory concentration of dexamethasone and the mRNA expression level of p38 MAPK (P<0.05), as well as significant increases in the mRNA expression levels of GR and MKP-1, the level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic GR ratio (P<0.05). CONCLUSIONS IFN-λ1 can inhibit the p38 MAPK pathway by upregulating MKP-1, promote the nuclear translocation of GR, and thus ameliorate GC resistance in HBECs.
Humans ; p38 Mitogen-Activated Protein Kinases/genetics* ; Glucocorticoids/pharmacology* ; Receptors, Glucocorticoid/analysis* ; Dual Specificity Phosphatase 1/physiology* ; Dexamethasone/pharmacology* ; Drug Resistance/drug effects* ; Respiratory Syncytial Viruses ; Interferons/pharmacology* ; MAP Kinase Signaling System/drug effects* ; Epithelial Cells/drug effects* ; Signal Transduction/drug effects* ; Cells, Cultured

OBJECTIVE: To explore the potential effects and mechanisms of Liang-Ge-San (LGS) for the treatment of acute respiratory distress syndrome (ARDS) through network pharmacology analysis and to verify LGS activity through biological experiments. METHODS: The key ingredients of LGS and related targets were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. ARDS-related targets were selected from GeneCards and DisGeNET databases. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed using the Metascape Database. Molecular docking analysis was used to confirm the binding affinity of the core compounds with key therapeutic targets. Finally, the effects of LGS on key signaling pathways and biological processes were determined by in vitro and in vivo experiments. RESULTS: A total of LGS-related targets and 496 ARDS-related targets were obtained from the databases. Network pharmacological analysis suggested that LGS could treat ARDS based on the following information: LGS ingredients luteolin, wogonin, and baicalein may be potential candidate agents. Mitogen-activated protein kinase 14 (MAPK14), recombinant V-Rel reticuloendotheliosis viral oncogene homolog A (RELA), and tumor necrosis factor alpha (TNF-α) may be potential therapeutic targets. Reactive oxygen species metabolic process and the apoptotic signaling pathway were the main biological processes. The p38MAPK/NF-κ B signaling pathway might be the key signaling pathway activated by LGS against ARDS. Moreover, molecular docking demonstrated that luteolin, wogonin, and baicalein had a good binding affinity with MAPK14, RELA, and TNF α. In vitro experiments, LGS inhibited the expression and entry of p38 and p65 into the nucleation in human bronchial epithelial cells (HBE) cells induced by LPS, inhibited the inflammatory response and oxidative stress response, and inhibited HBE cell apoptosis (P<0.05 or P<0.01). In vivo experiments, LGS improved lung injury caused by ligation and puncture, reduced inflammatory responses, and inhibited the activation of p38MAPK and p65 (P<0.05 or P<0.01). CONCLUSION LGS could reduce reactive oxygen species and inflammatory cytokine production by inhibiting p38MAPK/NF-κ B signaling pathway, thus reducing apoptosis and attenuating ARDS.
Drugs, Chinese Herbal/pharmacology* ; Respiratory Distress Syndrome/enzymology* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; NF-kappa B/metabolism* ; Animals ; Signal Transduction/drug effects* ; Molecular Docking Simulation ; Humans ; Male ; Network Pharmacology ; Apoptosis/drug effects* ; Mice

BACKGROUND: Drug resistance is the main cause of high mortality of lung cancer. This study was conducted to investigate the effect of folic acid (FA) on the resistance of non-small cell lung cancer (NSCLC) cells to Osimertinib (OSM) by regulating the methylation of dual specificity phosphatase 1 (DUSP1). METHODS: The OSM resistant NSCLC cell line PC9R was establishd by gradually escalation of OSM concentration in PC9 cells. PC9R cells were randomly grouped into Control group, OSM group (5 μmol/L OSM), FA group (600 nmol/L FA), methylation inhibitor decitabine (DAC) group (10 μmol/L DAC), FA+OSM group (600 nmol/L FA+5 μmol/L OSM), and FA+OSM+DAC group (600 nmol/L FA+5 μmol/L OSM+10 μmol/L DAC). CCK-8 method was applied to detect cell proliferation ability. Scratch test was applied to test the ability of cell migration. Transwell assay was applied to detect cell invasion ability. Flow cytometry was applied to measure and analyze the apoptosis rate of cells in each group. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) method was applied to detect the expression level of DUSP1 mRNA in cells. Methylation specific PCR (MSP) was applied to detect the methylation status of the DUSP1 promoter region in each group. Western blot was applied to analyze the expression levels of DUSP1 protein and key proteins in the DUSP1 downstream mitogen-activated protein kinase (MAPK) signaling pathway in each group. RESULTS: Compared with the Control group, the cell OD450 values (48 h, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the OSM group were obviously decreased (P<0.05); the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of extracellular regulated protein kinases (ERK) were obviously increased (P<0.05); the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the DAC group were obviously increased (P<0.05); the apoptosis rate, the expression of p38 MAPK protein, the phosphorylation level of ERK, and the methylation level of DUSP1 were obviously reduced (P<0.05). Compared with the OSM group, the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the FA+OSM group were obviously decreased (P<0.05); the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of ERK were obviously increased (P<0.05). Compared with the FA+OSM group, the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the FA+OSM+DAC group were obviously increased; the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of ERK were obviously reduced (P<0.05). CONCLUSIONS FA may inhibit DUSP1 expression by enhancing DUSP1 methylation, regulate downstream MAPK signal pathway, then promote apoptosis, inhibit cell invasion and metastasis, and ultimately reduce OSM resistance in NSCLC cells.
Humans ; Carcinoma, Non-Small-Cell Lung/genetics* ; Lung Neoplasms/genetics* ; Dual Specificity Phosphatase 1/pharmacology* ; Cell Proliferation ; p38 Mitogen-Activated Protein Kinases/pharmacology* ; Methylation ; Apoptosis ; Cell Line, Tumor

This study investigated the mechanism by which kaempferol(KAE) affected intervertebral disc degeneration(IDD) through the p38 mitogen-activated protein kinase(p38 MAPK) signaling pathway. Rats were randomly divided into five groups: control group, model group, low-dose KAE group, medium-dose KAE group, and high-dose KAE group. An IDD model was established by needle puncture of the caudal intervertebral discs. Four weeks post-surgery, the rats were administered KAE via gavage for 8 consecutive weeks. Magnetic resonance imaging(MRI) was performed, and samples were collected. In vitro, an inflammation model of nucleus pulposus cells(NPCs) induced by tumor necrosis factor-alpha(TNF-α) was constructed. Anisomycin was used to activate the p38 MAPK signaling pathway. NPCs were divided into blank, model, KAE, agonist, and KAE + agonist groups. After 1 day of treatment, cell proliferation activity was assessed using the CCK-8. Protein expression levels were determined by Western blot, and mRNA expression was measured by real-time quantitative polymerase chain reaction. Cell apoptosis was detected by TUNEL staining, and immunofluorescence staining was used to detect type Ⅱ collagen and matrix metalloproteinase 3(MMP3). In vivo results indicated significant improvement in the degree of IDD in the treatment groups compared to the model group, with the medium-dose group showing more pronounced therapeutic effects than the low-and high-dose groups. In vitro results demonstrated that KAE treatment significantly enhanced NPC proliferation activity, down-regulated the expression levels of Bcl-2-associated X protein(Bax), interleukin-6(IL-6), interleukin-17A(IL-17A), MMP3, and a disintegrin and metalloproteinase with thrombospondin motifs 5, and inhibited the phosphorylation of p38 MAPK pathway-related proteins. Activation of the p38 MAPK signaling pathway by anisomycin reduced the therapeutic effects of KAE. The study concluded that KAE could improve the proliferation activity of degenerated NPCs, reduce inflammation levels, and slow the progression of IDD in rats, and the mechanism was likely related to the regulation of the p38 MAPK signaling pathway.
Animals ; p38 Mitogen-Activated Protein Kinases/genetics* ; Kaempferols/pharmacology* ; Intervertebral Disc Degeneration/genetics* ; Rats ; Rats, Sprague-Dawley ; Male ; Apoptosis/drug effects* ; Cell Proliferation/drug effects* ; Nucleus Pulposus/drug effects* ; Signal Transduction/drug effects* ; Humans ; MAP Kinase Signaling System/drug effects*

The study is designed to observe the mechanism of Tongfu Xiefei Guanchang Solution(TFXF) in the treatment of acute lung injury(ALI) in rats by improving intestinal barrier and intestinal flora structure via p38 mitogen-activated protein kinase(p38 MAPK)/myosin light chain kinase(MLCK) signaling pathway. Sixty SPF-grade Wistar rats were randomly divided into the control(CON) group, lipopolysaccharide(LPS) group(7.5 mg·kg~(-1)), LPS + dexamethasone(DEX) group(3.5 mg·kg~(-1)), LPS + high-dose(HD)-TFXF group(14.74 g·kg~(-1)), LPS + middle-dose(MD)-TFXF group(7.37 g·kg~(-1)), and LPS + low-dose(LD)-TFXF group(3.69 g·kg~(-1)). ALI model of the rat was established by intraperitoneal injection of LPS. The lactate dehydrogenase(LDH) activity and total protein concentration in the bronchoalveolar lavage fluid(BALF) were measured; tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) levels in lung and colon tissue of rats were detected by enzyme linked immunosorbent assay(ELISA). Hematoxylin-eosin(HE) staining was used to observe the pathological expression in the lung and colon tissue of rats. The mRNA expression of p38 MAPK, TNF-α, and IL-1β in rat lung tissue was determined by real-time fluorescence quantitative polymerase chain reaction(real-time PCR). Western blot was used to detect the protein expression related to the p38 MAPK/MLCK signaling pathway in the colon tissue of rats. 16S rRNA sequencing was used to detect changes in the composition and content of intestinal flora in rats, and correlation analyses were performed to explore the regulatory role of intestinal flora in improving ALI in rats. The results showed that compared with those in the LPS group, the histopathological scores of lung and colon tissue, LDH activity, and total protein concentration in BALF were significantly reduced in rats in all groups after drug administration. Except for the LPS + LD-TFXF group, the remaining groups significantly reduced the levels of TNF-α and IL-1β in the lung and colon tissue of rats. The protein expressions of phosphorylated p38 mitogen-activated protein kinase(p-p38 MAPK)/p38, phosphorylated myosin light chain(p-MLC)/myosin light chain 2(MLC2), and MLCK in colon tissue of rats in each drug administration group were significantly decreased. The mRNA expression levels of p38 MAPK, TNF-α, and IL-1β were significantly reduced in the LPS + HD-TFXF group. 16S rRNA sequencing results showed that the abundance of intestinal flora was significantly higher in the LPS + HD-TFXF group, and intestinal floras including Sobs, Shannon, and Npshannon were significantly higher. The β-diversity distribution of intestinal flora tends toward the CON group, and the abundance of Firmicutes was significantly higher. The abundance of Proteobacteria was significantly reduced; the abundance of Bacteroides was significantly reduced, and the abundance of Ruminococcus was significantly higher. The main species differences were Blautia, Roseburia＿sp＿499, and Butyricicoccus. TNF-α and IL-1β of lung tissue were negatively correlated with Muribaculaceae, unclassified norank＿f＿Eubacterium＿coprostanoligenes, and Ruminococcus and positively correlated with Bacteroides. Meanwhile, TNF-α and IL-1β of colon tissue were negatively correlated with unclassified norank＿f＿Eubacterium＿coprostanoligenes and Ruminococcus and positively correlated with Bacteroides. The predicted biological function of the flora was related to the biosynthesis of secondary metabolites, amino acid biosynthesis, sugar metabolism, and oxidative phosphorylation. The above studies show that TFXF can repair lung and colon tissue structure and regulate inflammatory factor levels by modulating the abundance and diversity of intestinal flora species in ALI rats. Its mechanism of action in ameliorating ALI in rats may be related to the inhibition of inflammation, improvement of intestinal mucosal permeability, and maintenance of intestinal flora homeostasis and barrier through the p38 MAPK/MLCK signaling pathway.
Animals ; Acute Lung Injury/genetics* ; Rats ; p38 Mitogen-Activated Protein Kinases/genetics* ; Drugs, Chinese Herbal/pharmacology* ; Myosin-Light-Chain Kinase/genetics* ; Male ; Gastrointestinal Microbiome/drug effects* ; Rats, Wistar ; Signal Transduction/drug effects* ; Interleukin-1beta/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Lung/metabolism* ; Intestinal Mucosa/metabolism* ; Humans

This study aimed to elucidate the effect and underlying mechanism of Bovis Calculus in the treatment of ulcerative colitis(UC) through network pharmacological prediction and animal experimental verification. Databases such as BATMAN-TCM were used to mine the potential targets of Bovis Calculus against UC, and the pathway enrichment analysis was conducted. Seventy healthy C57BL/6J mice were randomly divided into a blank group, a model group, a solvent model(2% polysorbate 80) group, a salazosulfapyridine(SASP, 0.40 g·kg~(-1)) group, and high-, medium-, and low-dose Bovis Calculus Sativus(BCS, 0.20, 0.10, and 0.05 g·kg~(-1)) groups according to the body weight. The UC model was established in mice by drinking 3% dextran sulfate sodium(DSS) solution for 7 days. The mice in the groups with drug intervention received corresponding drugs for 3 days before modeling by gavage, and continued to take drugs for 7 days while modeling(continuous administration for 10 days). During the experiment, the body weight of mice was observed, and the disease activity index(DAI) score was recorded. After 7 days of modeling, the colon length was mea-sured, and the pathological changes in colon tissues were observed by hematoxylin-eosin(HE) staining. The levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6), and interleukin-17(IL-17) in colon tissues of mice were detected by enzyme-linked immunosorbent assay(ELISA). The mRNA expression of IL-17, IL-17RA, Act1, TRAF2, TRAF5, TNF-α, IL-6, IL-1β, CXCL1, CXCL2, and CXCL10 was evaluated by real-time polymerase chain reaction(RT-PCR). The protein expression of IL-17, IL-17RA, Act1, p-p38 MAPK, and p-ERK1/2 was investigated by Western blot. The results of network pharmacological prediction showed that Bovis Calculus might play a therapeutic role through the IL-17 signaling pathway and the TNF signaling pathway. As revealed by the results of animal experiments, on the 10th day of drug administration, compared with the solvent model group, all the BCS groups showed significantly increased body weight, decreased DAI score, increased colon length, improved pathological damage of colon mucosa, and significantly inhibited expression of TNF-α,IL-6,IL-1β, and IL-17 in colon tissues. The high-dose BCS(0.20 g·kg~(-1)) could significantly reduce the mRNA expression levels of IL-17, Act1, TRAF2, TRAF5, TNF-α, IL-6, IL-1β, CXCL1, and CXCL2 in colon tissues of UC model mice, tend to down-regulate mRNA expression levels of IL-17RA and CXCL10, significantly inhibit the protein expression of IL-17RA,Act1,and p-ERK1/2, and tend to decrease the protein expression of IL-17 and p-p38 MAPK. This study, for the first time from the whole-organ-tissue-molecular level, reveals that BCS may reduce the expression of pro-inflammatory cytokines and chemokines by inhibiting the IL-17/IL-17RA/Act1 signaling pathway, thereby improving the inflammatory injury of colon tissues in DSS-induced UC mice and exerting the effect of clearing heat and removing toxins.
Mice ; Animals ; Colitis, Ulcerative/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Interleukin-17/pharmacology* ; TNF Receptor-Associated Factor 2/pharmacology* ; TNF Receptor-Associated Factor 5/metabolism* ; Mice, Inbred C57BL ; Signal Transduction ; Colon ; p38 Mitogen-Activated Protein Kinases/metabolism* ; RNA, Messenger/metabolism* ; Dextran Sulfate/metabolism* ; Disease Models, Animal

To investigate the mechanism by which Cangxi Tongbi Capsules promote chondrocyte autophagy to inhibit knee osteoarthritis(KOA) progression by regulating the circRNA＿0008365/miR-1271/p38 mitogen-activated protein kinase(MAPK) pathway. The cell and animal models of KOA were established and intervened with Cangxi Tongbi Capsules, si-circRNA＿0008365, si-NC, and Cangxi Tongbi Capsules combined with si-circRNA＿0008365. Flow cytometry and transmission electron microscopy were employed to determine the level of apoptosis and observe autophagosomes, respectively. Western blot was employed to reveal the changes in the protein levels of microtubule-associated protein light chain 3(LC3)Ⅱ/Ⅰ, Beclin-1, selective autophagy junction protein p62/sequestosome 1, collagen Ⅱ, a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS-5), and p38 MAPK. The mRNA levels of circRNA＿0008365, miR-1271, collagen Ⅱ, and ADAMTS-5 were determined by qRT-PCR. Hematoxylin-eosin staining was employed to reveal the pathological changes of the cartilage tissue of the knee, and enzyme-linked immunosorbent assay to measure the levels of interleukin-1β(IL-1β) and tumor necrosis factor-alpha(TNF-α). The chondrocytes treated with IL-1β showed down-regulated expression of circRNA＿0008365, up-regulated expression of miR-1271 and p38 MAPK, lowered autophagy level, increased apoptosis rate, and accelerated catabolism of extracellular matrix. The intervention with Cangxi Tongbi Capsules up-regulated the expression of circRNA＿0008365, down-regulated the expression of miR-1271 and p38 MAPK, increased the autophagy level, decreased the apoptosis rate, and weakened the catabolism of extracellular matrix. However, the effect of Cangxi Tongbi Capsules was suppressed after interfering with circRNA＿0008365. The in vivo experiments showed that Cangxi Tongbi Capsules dose-dependently inhibited the p38 MAPK pathway, enhanced chondrocyte autophagy, and mitigated articular cartilage damage and inflammatory response, thereby inhibiting the progression of KOA in rats. This study indicated that Cangxi Tongbi Capsules promoted chondrocyte autophagy by regulating the circRNA＿0008365/miR-1271/p38 MAPK pathway to inhibit the development of KOA.
Rats ; Animals ; Chondrocytes ; Osteoarthritis, Knee/pathology* ; RNA, Circular/pharmacology* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; MicroRNAs/metabolism* ; Apoptosis ; Autophagy/genetics* ; Collagen/metabolism*

Neuropathic pain is one of the common complications of diabetes. Tetrahydropalmatine(THP) is a main active component of Corydalis Rhizoma with excellent anti-inflammatory and pain-alleviating properties. This study aims to investigate the therapeutic effect of THP on diabetic neuropathic pain(DNP) and the underlying mechanism. High-fat and high-sugar diet(4 weeks) and streptozotocin(STZ, 35 mg·kg~(-1), single intraperitoneal injection) were employed to induce type-2 DNP in rats. Moreover, lipopolysaccharide(LPS) was used to induce the activation of BV2 microglia in vitro to establish an inflammatory cellular model. Fasting blood glucose(FBG) was measured by a blood glucose meter. Mechanical withdrawal threshold(MWT) was assessed with von Frey filaments, and thermal withdrawal latency(TWL) with hot plate apparatus. The protein expression levels of OX42, inducible nitric oxide synthase(iNOS), CD206, p38, and p-p38 were determined by Western blot, the fluorescence expression levels of OX42 and p-p38 in the dorsal horn of the rat spinal cord by immunofluorescence, the mRNA content of p38 and OX42 in rat spinal cord tissue by qRT-PCR, and levels of nitric oxide(NO), interleukin-1β(IL-1β), interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), and serum fasting insulin(FINS) by enzyme-linked immunosorbent assay(ELISA). RESULTS:: showed that the mo-del group demonstrated significant decrease in MWT and TWL, with pain symptoms. THP significantly improved the MWT and TWL of DNP rats, inhibited the activation of microglia and p38 MAPK signaling pathway in rat spinal cord, and ameliorated its inflammatory response. Meanwhile, THP promoted the change of LPS-induced BV2 microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, suppressed the activation of the p38 MAPK signaling pathway, decreased the expression levels of inflammatory factors NO, IL-1β, IL-6, and TNF-α, and increased the expression level of anti-inflammatory factor IL-10. The findings suggested that THP can significantly ameliorate the pain symptoms of DNP rats possibly by inhibiting the inflammatory response caused by M1 polarization of microglia via the p38 MAPK pathway.
Animals ; Berberine Alkaloids ; Blood Glucose/metabolism* ; Diabetes Mellitus ; Diabetic Neuropathies/genetics* ; Interleukin-10 ; Interleukin-6/metabolism* ; Lipopolysaccharides/pharmacology* ; Microglia ; Neuralgia/metabolism* ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Spinal Cord/metabolism* ; Streptozocin/therapeutic use* ; Tumor Necrosis Factor-alpha/metabolism* ; p38 Mitogen-Activated Protein Kinases/metabolism*