[Effect of Hei Xiaoyaosan regulating p38MAPK/Beclin-1/Bcl-2 pathway on autophagy level in Alzheimer's disease model rats].

To explore the effect of Hei Xiaoyaosan on autophagy levels in Alzheimer's disease(AD). A total of 100 4-month-old Wistar male rats were randomly selected as a blank group, and 10 rats were taken as a sham operation group and injected with 1 µL of normal saline on both sides of the hippocampus. The other rats were injected with Aß_(1-42) solution in the hippocampus to replicate the AD model. Fifty successfully modeled rats were selected and randomly divided into the model group, Aricatio group(0.5 mg·kg~(-1)), and high, medium, and low dose groups of Hei Xiaoyaosan(15.30, 7.65, and 3.82 g·kg~(-1)), with 10 rats in each group. The rats were administered by continuous gavage for 42 days. Morris water maze was used to detect the learning and memory ability of rats, and Hoechst staining was used to observe the pathological changes of nerve cells in the hippocampal CA1 region. The mRNA expression of p38MAPK, Beclin-1, and Bcl-2 was detected by RT-qPCR.Western blot was used to detect the expressions of p38MAPK, Beclin-1, Bcl-2, APP, and related proteins. The level of Aß_(1-42) in the hippocampus was detected by ELISA, and the expression level of LC3Ⅱ in the hippocampus was detected by immunohistochemistry. The experimental results showed that compared with the blank group, the learning and memory ability of rats in the model group decreased(P<0.01). The nuclei in the CA1 region of the hippocampus showed blue bright spots and were closely arranged. The mRNA expression of p38MAPK was up-regulated, and the mRNA expressions of Beclin-1 and Bcl-2 were down-regulated(P<0.01). The expressions of p38MAPK, p-p38MAPK, and APP were increased, while those of Beclin-1, Bcl-2, and p-Bcl-2 were decreased(P<0.01). The expression of Aß_(1-42) was increased(P<0.01). The relative expression of LC3Ⅱ decreased(P<0.01). Compared with the model group, the learning and memory ability of rats in each administration group was improved(P<0.05 or P<0.01). The nuclei in the CA1 region of the hippocampus gradually became clear, showing light blue. The mRNA expression of p38MAPK was down-regulated(P<0.01), and that of Beclin-1 and Bcl-2 was increased(P<0.05 or P<0.01). The expressions of p38MAPK, p-p38MAPK, and APP were down-regulated, while those of Beclin-1, Bcl-2, and p-Bcl-2 were up-regulated(P<0.05 or P<0.01). The expression of Aß_(1-42) was decreased(P<0.01). The relative expression of LC3Ⅱ was increased(P<0.01). It can be concluded that Hei Xiaoyaosan can improve the cognitive ability of AD model rats, and its potential mechanism may be related to regulating the p38MAPK/Beclin-1/Bcl-2 signaling pathway, increasing the level of autophagy, and reducing the accumulation of Aß_(1-42).

Dahuang Zhechong Pill Alleviates Liver Fibrosis Progression by Regulating p38 MAPK/NF-κ B/TGF-ß1 Pathway.

OBJECTIVE: To explore the effect and mechanism of Dahuang Zhechong Pill (DHZCP) on liver fibrosis. METHODS: Liver fibrosis cell model was induced by transforming growth factor-ß (TGF-ß) in hepatic stellate cells (HSC-T6). DHZCP medicated serum (DMS) was prepared in rats. HSC-T6 cells were divided into the control (15% normal blank serum culture), TGF-ß (15% normal blank serum + 5 ng/mL TGF-ß), DHZCP (15% DMS + 5 ng/mL TGF-ß), DHZCP+PDTC [15% DMS + 4 mmol/L ammonium pyrrolidine dithiocarbamate (PDTC)+ 5 ng/mL TGF-ß], and PDTC groups (4 mmol/L PDTC + 5 ng/mL TGF-ß). Cell activity was detected by cell counting kit 8 and levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the cell supernatant were determined by enzyme-linked immunosorbnent assay. Western blot was used to measure the expressions of p38 mitogen-activated protein kinase/nuclear factor kappa B/transforming growth factor-ß1 (p38 MAPK/NF-κ B/TGF-ß1) pathway related proteins, and the localization and expressions of these proteins were observed by immunofluorescence staining. RESULTS: DHZCP improves the viability of cells damaged by TGF-ß and reduces inflammatory cytokines and ALT and AST levels in the supernatant of HSC-T6 cells induced with TGF-ß (P<0.05 or P<0.01). Compared with the TGF-ß group, NF-κ B p65 levels in the DHZCP group were decreased (P<0.05). p38 MAPK and NF-κ B p65 levels in the DHZCP+PDTC were also reduced (P<0.01). Compared with the TGF-ß group, the protein expression of Smad2 showed a downward trend in the DHZCP, DHZCP+PDTC, and PDTC groups (all P<0.01), and the decreasing trend of Samd3 was statistically significant only in DHZCP+PDTC group (P<0.01), whereas Smad7 was increased (P<0.05 or P<0.01). CONCLUSION: DHZCP can inhibit the process of HSC-T6 cell fibrosis by down-regulating the expression of p38 MAPK/NF-κ B/TGF-ß1 pathway.

Daphnetin Ameliorates Neuropathic Pain via Regulation of Microglial Responses and Glycerophospholipid Metabolism in the Spinal Cord.

Neuropathic pain (NP) is a common type of chronic pain caused by a lesion or disease of the somatosensory nervous system. This condition imposes a considerable economic burden on society and patients. Daphnetin (DAP) is a natural product isolated from a Chinese medicinal herb with various pharmacological activities, such as anti-inflammatory and analgesic properties. However, the underlying mechanisms of these effects are not fully understood. In the present study, we aimed to investigate DAP's anti-inflammatory and analgesic effects and explore the underlying mechanisms of action. The NP model was established as chronic constrictive injury (CCI) of the sciatic nerve, and pain sensitivity was evaluated by measuring the mechanical withdrawal threshold (MWT) and thermal withdrawal threshold (TWT). The activation of microglia in the spinal dorsal horn was measured via immunofluorescence staining. Protein levels were measured using a western blot assay. Using a mass-spectrometry proteomics platform and an LC-MS/MS-based metabolomics platform, proteins and metabolites in spinal cord tissues were extracted and analyzed. DAP treatment ameliorated the MWT and TWT in CCI rats. The expression of IL-1ß, IL-6, and TNF-α was inhibited by DAP treatment in the spinal cords of CCI rats. Moreover, the activation of microglia was suppressed after DAP treatment. The elevation in the levels of P2X4, IRF8, IRF5, BDNF, and p-P38/P38 in the spinal cord caused by CCI was inhibited by DAP. Proteomics and metabolomics results indicated that DAP ameliorated the imbalance of glycerophospholipid metabolism in the spinal cords of CCI rats. DAP can potentially ameliorate NP by regulating microglial responses and glycerophospholipid metabolism in the CCI model. This study provides a pharmacological justification for using DAP in the management of NP.

[Experimental study on promotion of peripheral nerve regeneration by selenium-methylselenocysteine].

Objective: To investigate the feasibility of selenium-methylselenocysteine (SMC) to promote peripheral nerve regeneration and its mechanism of action. Methods: Rat Schwann cells RSC96 cells were randomly divided into 5 groups, which were group A (without any treatment, control group), group B (adding 100 µmol/L H 2O 2), group C (adding 100 µmol/L H 2O 2+100 µmol/L SMC), group D (adding 100 µmol/L H 2O 2+200 µmol/L SMC), group E (adding 100 µmol/L H 2O 2+400 µmol/L SMC); the effect of SMC on cell proliferation was detected by MTT method, and the level of oxidative stress was detected by immunofluorescence for free radicals [reactive oxygen species (ROS)] after determining the appropriate dose group. Thirty-six 4-week-old male Sprague Dawley rats were randomly divided into 3 groups, namely, the sham operation group (Sham group), the sciatic nerve injury group (PNI group), and the SMC treatment group (SMC group), with 12 rats in each group; the rats in the PNI group were fed with food and water normally after modelling operation, and the rats in the SMC group were added 0.75 mg/kg SMC to the drinking water every day. At 4 weeks after operation, the sciatic nerves of rats in each group were sampled for neuroelectrophysiological detection of highest potential of compound muscle action potential (CMAP). The levels of inflammatory factors [interleukin 17 (IL-17), IL-6, IL-10 and oxidative stress factors catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA)] were detected by ELISA assay. The luxol fast blue (LFB) staining was used to observe the myelin density, fluorescence intensity of glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) was observed by immunofluorescence staining, and myelin morphology was observed by transmission electron microscopy with measurement of axon diameter. Western blot was used to detect the protein expressions of p38 mitogen-activated protein kinases (p38MAPK), phosphorylated p38MAPK (p-p38MAPK), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Results: MTT assay showed that the addition of SMC significantly promoted the proliferation of RSC96 cells, and the low concentration could achieve an effective effect, so the treatment method of group C was selected for the subsequent experiments; ROS immunofluorescence test showed that group B showed a significant increase in the intensity of ROS fluorescence compared with that of group A, and group C showed a significant decrease in the intensity of ROS fluorescence compared with that of group B ( P<0.05). Neuroelectrophysiological tests showed that the highest potential of CMAP in SMC group was significantly higher than that in PNI and Sham groups ( P<0.05). ELISA assay showed that the levels of IL-6, IL-17, and MDA in PNI group were significantly higher than those in Sham group, and the levels of IL-10, SOD, and CAT were significantly lower; the levels of IL-6, IL-17, and MDA in SMC group were significantly lower than those in PNI group, and the levels of IL-10, SOD, and CAT were significantly higher ( P<0.05). LFB staining and transmission electron microscopy showed that the myelin density and the diameter of axons in the SMC group were significantly higher than those of the PNI group and the Sham group ( P<0.05). Immunofluorescence staining showed that the fluorescence intensity of GFAP and MBP in the SMC group were significantly stronger than those in the PNI group and Sham group ( P<0.05). Western blot showed that the relative expressions of Nrf2 and HO-1 proteins in the SMC group were significantly higher than those in the PNI group and Sham group, and the ratio of p-p38MAPK/p38MAPK proteins was significantly higher in the PNI group than that in the SMC group and Sham group ( P<0.05). Conclusion: SMC may inhibit oxidative stress and inflammation after nerve injury by up-regulating the Nrf2/HO-1 pathway, and then inhibit the phosphorylation of p38MAPK pathway to promote the proliferation of Schwann cells, which ultimately promotes the formation of myelin sheaths and accelerates the regeneration of peripheral nerves.

TNFR1/p38αMAPK signaling in Nex + supraspinal neurons regulates estrogen-dependent chronic neuropathic pain.

Upregulation of soluble tumor necrosis factor (sTNF) cytokine signaling through TNF receptor 1 (TNFR1) and subsequent neuronal hyperexcitability are observed in both animal models and human chronic neuropathic pain (CNP). Previously, we have shown that estrogen modulates sTNF/TNFR1 signaling in CNP, which may contribute to female prevalence of CNP. The estrogen-dependent role of TNFR1-mediated supraspinal neuronal circuitry in CNP remains unknown. In this study, we interrogated the intersect between supraspinal TNFR1 mediated neuronal signaling and sex specificity by selectively removing TNFR1 in Nex + neurons in adult mice (NexCreERT2::TNFR1f/f). We determined that mechanical hypersensitivity induced by chronic constriction injury (CCI) decreases over time in males, but not in females. Subsequently, we investigated two downstream pathways, p38MAPK and NF-κB, important in TNFR1 signaling and injury response. We detected p38MAPK and NF-κB activation in male cortical tissue; however, p38MAPK phosphorylation was reduced in NexCreERT2::TNFR1f/f males. We observed a similar recovery from acute pain in male mice following CCI when p38αMAPK was knocked out of supraspinal Nex + neurons (NexCreERT2::p38αMAPKf/f), while chronic pain developed in female mice. To explore the intersection between estrogen and inflammation in CNP we used a combination therapy of an estrogen receptor ß (ER ß) inhibitor with a sTNF/TNFR1 or general p38MAPK inhibitor. We determined both combination therapies lends therapeutic relief to females following CCI comparable to the response evaluated in male mice. These data suggest that TNFR1/p38αMAPK signaling in Nex + neurons in CNP is male-specific and lack of therapeutic efficacy following sTNF inhibition in females is due to ER ß interference. These studies highlight sex-specific differences in pathways important to pain chronification and elucidate potential therapeutic strategies that would be effective in both sexes.

RNA polymerase I subunit D activated by Yin Yang 1 transcription promote cell proliferation and angiogenesis of colorectal cancer cells.

This study aims to explore possible effect of RNA polymerase I subunit D (POLR1D) on proliferation and angiogenesis ability of colorectal cancer (CRC) cells and mechanism herein. The correlation of POLR1D and Yin Yang 1 (YY1) expressions with prognosis of CRC patients in TCGA database was analyzed. Quantitative realtime polymerase chain reaction (qRT-PCR) and Western blot were applied to detect expression levels of POLR1D and YY1 in CRC cell lines and CRC tissues. SW480 and HT- 29 cells were transfected with si-POLR1D or pcDNA3.1-POLR1D to achieve POLR1D suppression or overexpression before cell migration, angiogenesis of human umbilical vein endothelial cells were assessed. Western blot was used to detect expressions of p38 MAPK signal pathway related proteins and interaction of YY1 with POLR1D was confirmed by dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). TCGA data showed that both POLR1D and YY1 expressions were up-regulated in CRC patients. High expression of POLR1D was associated with poor prognosis of CRC patients. The results showed that POLR1D and YY1 were highly expressed in CRC cell lines. Inhibition or overexpression of POLR1D can respectively suppress or enhance proliferation and angiogenesis of CRC cells. YY1 inhibition can suppress CRC progression and deactivate p38 MAPK signal pathway, which can be counteracted by POLR1D overexpression. JASPAR predicted YY1 can bind with POLR1D promoter, which was confirmed by dual luciferase reporter gene assay and ChIP. YY1 transcription can up-regulate POLR1D expression to activate p38 MAPK signal pathway, thus promoting proliferation and angiogenesis ability of CRC cells.

Dexmedetomidine alleviates blood-brain barrier disruption in rats after cerebral ischemia-reperfusion by suppressing JNK and p38 MAPK signaling.

Dexmedetomidine displays multiple mechanisms of neuroprotection in ameliorating ischemic brain injury. In this study, we explored the beneficial effects of dexmedetomidine on blood-brain barrier (BBB) integrity and neuroinflammation in cerebral ischemia/reperfusion injury. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 1.5 h and reperfusion for 24 h to establish a rat model of cerebral ischemia/reperfusion injury. Dexmedetomidine (9 􀁐g/kg) was administered to rats 30 min after MCAO through intravenous injection, and SB203580 (a p38 MAPK inhibitor, 200 􀁐g/kg) was injected intraperitoneally 30 min before MCAO. Brain damages were evaluated by 2,3,5-triphenyltetrazolium chloride staining, hematoxylin-eosin staining, Nissl staining, and brain water content assessment. BBB permeability was examined by Evans blue staining. Expression levels of claudin-5, zonula occludens-1, occludin, and matrix metalloproteinase-9 (MMP-9) as well as M1/M2 phenotypes-associated markers were assessed using immunofluorescence, RT-qPCR, Western blotting, and gelatin zymography. Enzyme-linked immunosorbent assay was used to examine inflammatory cytokine levels. We found that dexmedetomidine or SB203580 attenuated infarct volume, brain edema, BBB permeability, and neuroinflammation, and promoted M2 microglial polarization after cerebral ischemia/reperfusion injury. Increased MMP-9 activity by ischemia/reperfusion injury was inhibited by dexmedetomidine or SB203580. Dexmedetomidine inhibited the activation of the ERK, JNK, and p38 MAPK pathways. Moreover, activation of JNK or p38 MAPK reversed the protective effects of dexmedetomidine against ischemic brain injury. Overall, dexmedetomidine ameliorated brain injury by alleviating BBB permeability and promoting M2 polarization in experimental cerebral ischemia/reperfusion injury model by inhibiting the activation of JNK and p38 MAPK pathways.

Blockage of the fractalkine pathway reduces hyperalgesia and prevents morphological glial alterations-Comparison between inflammatory and neuropathic orofacial pain in male rats.

This study aimed to evaluate the effects of inhibitors of the fractalkine pathway in hyperalgesia in inflammatory and neuropathic orofacial pain in male rats and the morphological changes in microglia and satellite glial cells (SGCs). Rats were submitted to zymosan-induced arthritis of the temporomandibular joint or infraorbital nerve constriction, and treated intrathecally with a P2 X7 antagonist, a cathepsin S inhibitor or a p-38 mitogen-activated protein kinase (MAPK) inhibitor. Mechanical hyperalgesia was evaluated 4 and 6 h following arthritis induction or 7 and 14 days following nerve ligation. The expression of the receptor CX3 CR1 , phospho-p-38 MAPK, ionized calcium-binding adapter molecule-1 (Iba-1), and glutamine synthetase and the morphological changes in microglia and SGCs were evaluated by confocal microscopy. In both inflammatory and neuropathic models, untreated animals presented a higher expression of CX3 CR1 and developed hyperalgesia and up-regulation of phospho-p-38 MAPK, which was prevented by all drugs (p < .05). The number of microglial processes endpoints and the total branch length were lower in the untreated animals, but the overall immunolabeling of Iba-1 was altered only in neuropathic rats (p < .05). The mean area of SGCs per neuron was significantly altered only in the inflammatory model (p < .05). All morphological alterations were reverted by modulating the fractalkine pathway (p < .05). In conclusion, the blockage of the fractalkine pathway seemed to be a possible therapeutic strategy for inflammatory and neuropathic orofacial pain, reducing mechanical hyperalgesia by impairing the phosphorylation of p-38 MAPK and reverting morphological alterations in microglia and SGCs.

Effect of acupoint catgut embedding on p38 MAPK pathway in the lung tissue of asthmatic rats. / 穴位埋线通过调节p38ä¸è£‚åŽŸæ´»åŒ–è›‹ç™½æ¿€é ¶é€šè·¯å¯¹å“®å–˜å¤§é¼ æ°”é“ä¸Šçš®çš„å½±å“.

OBJECTIVES: To observe the effect of catgut embedding at "Feishu"(BL13), "Dingchuan" (EX-B1) and "Danzhong" (CV17) on expression of phosphorylated p38 mitogen activated protein kinase (p-p38 MAPK), interleukin-4 (IL-4), interferon-γ (IFN-γ) and changes of airway epithelial cells (AEC) in the lung tissue of bronchial asthma (BA) rats, so as to explore its mechanisms underlying improvement of BA. METHODS: Forty male Wistar rats were randomly and equally divided into blank control, model, dexamethasone (DEX) and catgut embedding groups. The BA model was established by intraperitoneal injection of suspension of ovalbumin and aluminum hydroxide. Rats of the DEX group received intraperitoneal injection of DEX (1.5 mg/kg), once daily for 2 weeks, and those of the catgut embedding group received catgut embedding at BL13, EX-B1 and CV17 only one time. The rats' sneezing times per miniute in each group were recorded. H.E. staining was used to observe the histopathological changes of the lung tissue under light microscope. A transmission electron microscope (TEM) was used to observe the ultrastructural changes of AEC in the lung tissue, including the thickness of bronchial wall and bronchial smooth muscle by using an image analysis software. The protein expressions of p-p38 MAPK, IL-4 and INF-γ in the lung tissue were determined using Western blot. RESULTS: Morphological observation revealed that in the model group, light microscope showed deformed and swollen bronchial tube wall with increased folds and thickened bronchial smooth muscle；and TEM showed a large number of autophagy vesicles containing swollen and deformed organelles in the AEC, and apparent reduction of intracellular mitochondria, these situations were obviously milder in both DEX and catgut embedding groups. Compared with the blank control group, the sneezing times, thickness of bronchial wall and bronchial smooth muscle in the model group were significantly increased (P<0.01), and the expressions of p-p38 MAPK and IL-4 in lung tissue were significantly increased (P<0.01), while the expression of IFN-γ was significantly decreased (P<0.01) in the model group. In comparison with the model group, the sneezing times, thickness of bronchial wall and bronchial smooth muscle, protein expressions of p-p38 MAPK and IL-4 were significantly decreased (P<0.01), while the expression of IFN-γ was obviously increased (P<0.01) in both the DEX and catgut embedding groups. CONCLUSIONS: Acupoint catgut embedding can reduce the expression of IL-4 and increase the expression of IFN-γ by inhibiting p38 MAPK signal pathway of lung tissues in BA rats, which may contribute to its effect in alleviating the degree of airway epithelial cells damage.

Chaihu Longgu Mulitang Relieves Generalized Anxiety Disorder in Rats via p38 MAPK/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study whether Chaihu Longgu Mulitang can inhibit hypothalamic inflammation， mitigate anxiety-like behavior， and alleviate anxiety symptoms by regulating the p38 mitogen-activated protein kinase/nuclear factor-κB （p38 MAPK/NF-κB） signaling pathway in the rat model of generalized anxiety disorder （GAD）. MethodTwelve out of 74 Wistar rats were randomly selected as the blank group， and the remaining rats were subjected to chronic restraint stress for the modeling of GAD. The open field test （OFT） and elevated Porteus maze test （PMT） were conducted 14 days after modeling to detect the anxiety-like behaviors. Sixty successfully modeled rats were selected and randomized into model， low-， medium-， and high-dose （6， 12， and 24 g·kg-1， respectively） Chaihu Longgu Mulitang， and diazepam （1 mg·kg-1） groups （n=12） and administrated with corresponding drugs for 14 consecutive days. OFT and PMT were then carried out to examine the anxiety-like behaviors of the rats. The levels of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and interleukin-1β （IL-1β） in the hypothalamus and serum of rats were determined by the enzyme-linked immunosorbent assay （ELISA）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）was conducted to determine the mRNA levels of p38 MAPK， NF-κB p65， nuclear factor κB inhibitor α （IκBα）， and ionized calcium binding adaptor molecule 1 （Iba-1）. The protein levels of p38 MAPK， phosphorylated （p）-p38 MAPK， NF-κB p65， p-NF-κB p65， and IκBα in the hypothalamus of rats were determined by Western blot. The expression of Iba-1 in the hypothalamic microglia was detected by immunofluorescence assay. ResultCompared with the blank group， the model group had decreased body weight， scattered dark yellow fur， increased irritability， and preference to hibernation in the corner. In addition， the modeled rats showed increased edge movement distance and time in OFT （P<0.01） and decreased movement distance and time and the number of entries in the open arm in PMT （P<0.01）. The modeling increased the fluorescence intensity of Iba-1 in paraventricular nucleus of hypothalamus （P<0.01）， elevated the levels of IL-1β， IL-6， and TNF-α in the serum and hypothalamus （P<0.01）， up-regulated the protein and mRNA levels of p38 MAPK， NF-κB p65， p-p38 MAPK， p-NF-κB p65， and Iba-1 （P<0.05， P<0.01）， and down-regulated the protein and mRNA levels of IκBα （P<0.01） in the hypothalamus. Compared with the model group， medium- and high-dose Chaihu Longgu Mulitang and diazepam increased the body weight， improved the fur and behaviors， decreased the edge movement distance and time in OFT （P<0.05， P<0.01）， and increased the movement distance and time in the open arm in PMT （P<0.05， P<0.01）. Furthermore， they decreased the fluorescence intensity of Iba-1 in hypothalamic microglia （P<0.05， P<0.01）， lowered the levels of IL-1β， IL-6， and TNF-α in the serum and hypothalamic tissue （P<0.05， P<0.01）， down-regulated the mRNA and protein levels of p38 MAPK， NF-κB p65， p-p38 MAPK， p-NF-κB p65， and Iba-1 （P<0.05， P<0.01）， and up-regulated the mRNA and protein levels of IκBα （P<0.05， P<0.01） in the hypothalamus. ConclusionChaihu Longgu Mulitang can mitigate anxiety-like behaviors and relieve anxiety in GAD rats by inhibiting the p38 MAPK/NF-κB signaling pathway and reducing the activation of microglia and the levels of pro-inflammatory cytokines in the hypothalamus.

Effect of Guipitang on ERK1/2 and p38 MAPK in Rats with Myocardial Ischemia / 中国实验方剂学杂志

ObjectiveTo explore the therapeutic effect and mechanism of Guipitang on rats with myocardial ischemia. MethodFifty SD rats were divided into five groups： a control group， a model group， low and high-dose Guipitang （7.52， 15.04 g·kg-1） groups， and a trimetazidine group （0.002 g·kg-1）. By intragastric administration of vitamin D3 and feeding rats with high-fat forage and injecting isoproterenol， the rat model of myocardial ischemia was established. After drug treatment of 15 d， an electrocardiogram （ECG） was performed to analyze the degree of myocardial injury. A fully automatic biochemical analyzer was used to detect the changes in the serum levels of total cholesterol （TC）， high-density lipoprotein cholesterol （HDL-C）， triglyceride （TG）， and low-density lipoprotein cholesterol （LDL-C）. Hematoxylin-eosin （HE） staining and Masson staining were used to observe myocardial histopathological changes. TdT-mediated dUTP nick end labeling （TUNEL） staining was used to detect cardiomyocyte apoptosis. Western blot was adopted to detect the protein levels of extracellular signal-regulated kinase 1/2 （ERK1/2）， phospho-ERK1/2 （p-ERK1/2）， p38 mitogen-activated protein kinase （p38 MAPK）， phospho-p38 MAPK （p-p38 MAPK）， B-cell lymphoma-2 （Bcl-2）-associated X （Bax）， Bcl-2， and cleaved cysteine aspartate proteolytic enzyme （cleaved Caspase-3）. ResultCompared with the control group， the ECG S-T segment decreased in the model group. The serum levels of TC， TG， and LDL-C were increased significantly （P<0.05）. The arrangement of myocardial tissue was disordered， and the proportion of cardiomyocyte apoptosis increased. The protein levels of cleaved Caspase-3， Bax， and p-p38 MAPK in the heart were increased， and the Bcl-2 expression was decreased （P<0.05）. Compared with the model group， the S-T segment downward shift was restored in the low and high-dose Guipitang groups and trimetazidine group， and the levels of TC， TG， and LDL-C were decreased. The protein expression of cleaved Caspase-3 and Bax in the heart dropped， and p-p38 MAPK and p-ERK1/2 protein expressions increased significantly （P<0.05）. The degree of myocardial injury was alleviated， and the proportion of cardiomyocyte apoptosis decreased. Bcl-2 protein expression was increased significantly in the low-dose Guipitang group （P<0.05）. ERK1/2 and p38 MAPK proteins had no significant difference among different groups. ConclusionGuipitang could alleviate myocardial injury and inhibit cardiomyocyte apoptosis in rats by activating the expression of ERK1/2 and p38 MAPK.

Effect and Mechanism of Action of Epimedii Folium Polysaccharides on Mice with Exercise-induced Fatigue Based on p38 MAPK/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study the effects of Epimedii Folium polysaccharides on mice with exercise-induced fatigue and explore its possible mechanism of action. MethodICR male mice screened by swimming training were randomly divided into a control group， model group， vitamin C group， and low， medium， and high dose groups of Epimedii Folium polysaccharides， with eight mice in each group. The exercise-induced fatigue model was established by weight-bearing swimming training in each group except for the control group. After two weeks of weight-bearing swimming， the Epimedii Folium polysaccharide groups were given 100， 200， 400 mg∙kg-1 of Epimedii Folium polysaccharides by gavage， and the vitamin C group was given 200 mg∙kg-1 of vitamin C by gavage. The control group and the model group were given equal amounts of saline for 14 d. At the end of the experimental period， the body mass of the mice in each group and the time of last swimming due to exhaustion were recorded. Serum urea nitrogen （BUN）， lactic acid （LA）， lactate dehydrogenase （LDH）， malondialdehyde （MDA）， superoxide dismutase （SOD）， glutathione peroxidation （GSH-Px）， myoglycogen （MG） in skeletal muscle， hepatic glycogen （HG） in the liver were detected by kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in muscle tissue. Western blot was used to detect the protein expression of p38 mitogen-activated protein kinase （p38 MAPK）， phosphorylation （p）-p38 MAPK， extracellular signal-regulated kinase1/2 （ERK1/2）， nuclear factor-κB （NF-κB）， p-NF-κB， interleukin-1β （IL-1β）， and interleukin-6 （IL-6） in muscle tissue. The immunofluorescence （IF） method was used to detect the expression of tumor necrosis factor-α （TNF-α） in skeletal muscle tissue of mice in each group. ResultCompared with the control group， the body mass of mice in the model group decreased， and the time of last swimming due to exhaustion decreased （P<0.01）. In addition， there were significantly higher serum levels of the fatigue metabolites LA， LDH， BUN， and lipid peroxidation product MDA （P<0.01） and decreased levels of MG， HG， SOD， and GSH-Px （P<0.01）. The protein expressions of p-p38 MAPK， ERK1/2， p-NF-κB， IL-1β， IL-6， and TNF-α in skeletal muscle tissue were significantly higher than those of the control group （P<0.01）. Compared with the model group， the body mass and time of last swimming due to exhaustion of the mice in the low， medium， and high dose groups of Epimedii Folium polysaccharides and the vitamin C group were increased （P<0.05， P<0.01）， and the contents of LA， LDH， BUN， and MDA were significantly decreased （P<0.05， P<0.01）. The levels of MG， HG， SOD， and GSH-Px increased （P<0.05， P<0.01）， and the protein expression levels of p-p38 MAPK， ERK， p-NF-κB， IL-1β， IL-6， and TNF-α in skeletal muscle tissue decreased （P<0.05， P<0.01）. ConclusionEpimedii Folium polysaccharides can play a role in alleviating exercise-induced fatigue by inhibiting the p38 MARK/NF-κB signaling pathway， thereby reducing the accumulation of metabolites， improving the activity of antioxidant enzymes， increasing the glycogen content of the body， and reducing inflammation in skeletal muscle.

Improvement effect of Phellodendron amurense polysaccharides on gouty nephropathy in rats and its mechanism / 中国药房

OBJECTIVE To study the effects of Phellodendron amurense polysaccharides （PAP） on improving gouty nephropathy （GN） in rats， and to investigate its mechanism primarily by interfering the p38 mitogen-activated protein kinase （p38 MAPK）/nuclear factor-κB（NF-κB）/tumor necrosis factor-α（TNF-α）. METHODS Sixty rats were randomly divided into normal group （water）， model group （water）， allopurinol group （positive control， 20 mg/kg）， PAP high-dose， medium-dose and low-dose groups （100， 50， 25 mg/kg， by raw material） after being stratified by body weight， with 10 rats in each group. Except for the normal group， the other groups were induced to construct GN model by giving 1 500 mg/kg potassium oxazinate and 100 mg/kg adenine intragastrically for 14 days. After modeling， the rats in each group were given relevant medicine/water intragastrically， once a day， for consecutive 28 days. After the last medication， the levels of biochemical parameters related to renal function [uric acid， creatinine （Cr）， blood urea nitrogen （BUN）， xanthine oxidase （XOD）] were detected in rats， and the histopathological changes in the rat kidney were observed. The protein expressions of monocyte chemoattractant protein-1（MCP-1），TNF-α and interleukin-6（IL-6） as well as the phosphorylation levels of p38 MAPK and NF-κB p65 protein were determined in renal tissue of rats. RESULTS Compared with the normal group， the model group suffered from the dilatation of renal tubules， structural damage to glomeruli， accompanied by inflammatory infiltration and fibrosis； the contents of uric acid， Cr， BUN and XOD， the protein expressions of MCP-1，TNF-α and IL-6 and the phosphorylation levels of p38 MAPK and NF-κB p65 protein were all increased significantly （P＜0.05 or P＜0.01）. Compared with the model group， the pathological symptoms of renal tissue in rats had been improved to varying degrees in different dose groups of PAP； the contents of uric acid， Cr， BUN and XOD， protein expressions of MCP-1， TNF-α and IL-6， the phosphorylation levels of p38 MAPK and NF-κB p65 protein in PAP high-dose and PAP medium-dose groups were all decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS PAP exhibits an anti-GN effect， the mechanism of which may be associated with inhibiting the p38 MAPK/NF-κB/TNF-α signaling pathway.

Chronic Allergen Exposure Contributes to Steroid Resistance via Increased Phosphorylation of Glucocorticoid Receptors S226 and p38 MAPK in a Mouse Model of Asthma.

Chronic allergen exposure can significantly induce p38 mitogen-activated protein kinase (MAPK) activation in asthma. p38 MAPK is involved in steroid resistance through phosphorylation of glucocorticoid receptors (GR) at S226. This study aims to investigate whether chronic allergen exposure can induce steroid resistance and whether it is associated with p38 MAPK activation in asthma. A mouse model of asthma was prepared by sensitizing and challenging mice with chronic ovalbumin (OVA) exposure. Key features of allergic asthma, encompassing bronchial hyperresponsiveness, pathology of lung tissues, cytokine profiles of inflammation in bronchoalveolar lavage fluid (BALF), and serum immunoglobulin (Ig)E concentration were evaluated. Furthermore, suppressive effects of corticosteroid on the splenocytes under stimulation of lipopolysaccharides, glucocorticoid receptor (GR) DNA binding ability of splenocytes, expression of GRα and phosphorylation of GR s226 in splenocytes, and p38 MAPK phosphorylation in splenocytes and lung tissues were determined. Chronic OVA exposure substantially induced airway hypersensitivity, leading to increased inflammatory infiltration in lung tissues. Additionally, it resulted in elevated levels of interleukin (IL)-4, IL-5, and IL-6 in BALF, as well as heightened levels of IgE in serum. Furthermore, OVA exposure substantially enhanced p38 MAPK phosphorylation in lung tissues. It also weakened the suppressive impacts of corticosteroids on splenocytes, impaired the GR DNA binding ability, and led to an enhanced phosphorylated state of GR S226 and p38 MAPK in splenocytes. Taken together, chronic allergen exposure contributes to steroid resistance in asthma, which is linked to an increased phosphorylated state of GR S226 and p38 MAPK.

Opposing Roles for the α Isoform of the Catalytic Subunit of Protein Phosphatase 1 in Inside-Out and Outside-In Integrin Signaling in Murine Platelets.

Platelet activation during hemostasis and thrombosis is facilitated by agonist-induced inside-out and integrin αIIbß3-initiated outside-in signaling via protein kinases and phosphatases. Pharmacological inhibitor studies suggest that the serine/threonine protein phosphatase 1 (PP1) promotes platelet activation. However, since phosphatase inhibitors block all the isoforms of the catalytic subunit of PP1 (PP1c), the role of specific PP1c isoform in platelet signaling remains unclear. Here, we employed a platelet-specific PP1cα-/- mice to explore the contribution of a major PP1 isoform in platelet functions. Loss of PP1cα moderately decreased activation of integrin αIIbß3, binding of soluble fibrinogen, and aggregation to low-dose thrombin, ADP, and collagen. In contrast, PP1cα-/- platelets displayed increased adhesion to immobilized fibrinogen, fibrin clot retraction, and thrombus formation on immobilized collagen. Mechanistically, post-fibrinogen engagement potentiated p38 mitogen-activated protein kinase (MAPK) activation in PP1cα-/- platelets and the p38 inhibitor blocked the increased integrin-mediated outside-in signaling function. Tail bleeding time and light-dye injury-induced microvascular thrombosis in the cremaster venules and arterioles were not altered in PP1cα-/- mice. Thus, PP1cα displays pleiotropic signaling in platelets as it amplifies agonist-induced signaling and attenuates integrin-mediated signaling with no impact on hemostasis and thrombosis.

Protein phosphatase 6 promotes transforming growth factor-ß signaling in mouse embryonic fibroblasts.

Transforming growth factor-beta (TGF-ß) is a multifunctional cytokine that controls various cellular processes. Protein phosphatase 6 (PP6) is an evolutionarily conserved serine/threonine protein phosphatase with diverse functions in cell signaling. However, it has not been linked to TGF-ß signaling. We found that TGF-ß treatment increased PP6 protein levels via transcriptional and post-translational regulation. Loss of the Ppp6c gene suppressed TGF-ß-induced canonical Smad3 phosphorylation and its transcriptional activity. PP6 knockout also inhibited non-canonical p38 mitogen-activated protein kinase (MAPK) pathway. Moreover, PP6 depletion suppressed cell migration induced by TGF-ß. These findings uncovered the role of PP6 as a positive regulator for TGF-ß signaling.

The p38-MITOGEN-ACTIVATED PROTEIN KINASE Signaling Pathway Is Involved in Leonurus artemisia Extract-Induced Inhibition of the Proliferation of Human Bladder Cancer BFTC-905 Cells via G1/G0 Arrest and Causes Apoptosis In Vitro.

Bladder cancer is a urothelial malignancy. Bladder cancer starts in the urothelial cells lining the inside of the bladder. The 5-year recurrence rate for bladder cancer ranges from 31% to 78%, and the progression rate is approximately 45%. To treat bladder cancer, intravesical drug therapy is often used. Leonurus artemisia extract (LaE) was obtained from medicinal samples of Chinese motherwort Scientific Chinese Medicine; L. artemisia has various biological effects. This study investigated the impact of LaE on human bladder cancer cells (the BFTC-905 cell line) and the molecular mechanism underlying apoptosis resulting from the activation of cell signal transduction pathways in bladder cancer cells. A cell counting kit-8 (CCK-8) assay was used to determine the effect of LaE on cell growth. The effect of LaE on migration ability was observed using a wound healing assay. The effects of LaE on the cell cycle, reactive oxygen species production, and apoptosis were investigated. Western blot analysis detected apoptosis-related and mitogen-activated protein kinase signaling pathway-related protein concentrations. At non-toxic concentrations, LaE inhibited the proliferation of BFTC-905 cells in a concentration-dependent manner, and the half-maximal inhibitory concentration (IC50) was 24.08172 µg/µL. LaE impaired the migration ability of BFTC-905 cells. LaE arrested the cell cycle in the G1 and G0 phases, increased reactive oxygen species production, and induced apoptosis. LaE increased Bax and p-ERK concentrations and decreased Bcl-2, cleaved caspase-3, and p-p38 concentrations. No differences in PARP, C-PARP, vimentin, e-cadherin, p-JNK, or TNF-alpha concentrations were observed. These results suggest that LaE inhibits the proliferation of human bladder cancer cells. Moreover, the mitogen-activated protein kinase signaling pathway is involved in the inhibition of the proliferation of BFTC-905 cells.

TNFR1/p38αMAPK signaling in Nex+ supraspinal neurons regulates sex-specific chronic neuropathic pain.

Upregulation of soluble tumor necrosis factor (sTNF) cytokine signaling through TNF receptor 1 (TNFR1) and subsequent neuronal hyperexcitability are observed in both animal models and human chronic neuropathic pain (CNP) [1-4]. To test the hypothesis that supraspinal circuitry is critical to pain chronification, we studied the intersect between supraspinal TNFR1 mediated neuronal signaling and sex specificity by selectively removing TNFR1 in Nex + neurons in adult mice (NexCreERT2::TNFR1f/f). We determined that following chronic constriction injury (CCI), pain resolves in males; however, female acute pain transitions to chronic. Subsequently, we investigated two downstream pathways, p38MAPK and NF-κB, important in TNFR1 signaling and injury response. We detected p38αMAPK and NF-κB activation in male cortical tissue; however, p38αMAPK phosphorylation was reduced in NexCreERT2::TNFR1f/f males. We observed similar behavioral results following CCI in NexCreERT2::p38αMAPKf/f mice. Previously, we established estrogen's ability to modulate sTNF/TNFR1 signaling in CNP, which may contribute to female prevalence of CNP [5-9]. To explore the intersection between estrogen and inflammation in CNP we used a combination therapy of an estrogen receptor ß (ER ß) inhibitor with a sTNF/TNFR1 or general p38MAPK inhibitor. We determined both combination therapies lend "male-like" therapeutic relief to females following CCI. These data suggest that TNFR1/p38αMAPK signaling in Nex + neurons in CNP is male-specific and lack of therapeutic efficacy following sTNF inhibition in females is due to ER ß interference. These studies highlight sex-specific differences in pathways important to pain chronification and elucidate potential therapeutic strategies that would be effective in both sexes.

Spinosin protects Neuro-2a/APP695 cells from oxidative stress damage by inactivating p38.

OBJECTIVE: To explore the protective mechanism of spinosin (SPI) on Alzheimer's disease (AD) model cells, Neuro-2a/APP695 (N2a/APP695), against HO-induced oxidative stress damage, to reflect the influence of oxidative stress on the development of AD, and to provide a valuable basis for the research and development of therapeutic drug for AD. METHODS: N2a/APP695 cells were exposed to HO and then treated with spinosin. Firstly, the secretion level of amyloid ß (Aß) and the production of malondialdehyde (MDA) and lactate dehydrogenase (LDH) were detected by enzyme linked immunosorbent assay kits. Secondly, the oligomerization degree of Aß was performed by Thioflavin T staining. Thirdly, the expression levels of p-Tau (Ser199/202/396), synaptophysin (SYP), postsynaptic density protein 95 (PSD95), and mitogen-activated protein kinase (MAPK) family-related proteins were detected by Western blot analysis. In addition, FITC-labeled phalloidin was used in cytoskeleton staining to reflect synaptic function. RESULTS: This study showed that HO stimulated N2a/APP695 cells to produce excessive MDA and LDH and secrete a large amount of Aß, promoted the aggregation of Aß, induced Tau protein hyperphosphorylation, and led to synaptic dysfunction. Spinosin reversed these changes caused by HO by inactivating p38, which was verified by treatment with the p38 inhibitor BIRB796. CONCLUSION: Spinosin protects N2a/APP695 cells from oxidative stress damage caused by HO through inactivating p38.