Effects of invigorating-spleen and anticancer prescription on extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway in colon cancer mice model

BACKGROUND Colon cancer(CC)is one of the most common malignant tumors in the gastrointestinal system.Overall,CC had the third highest incidence but the second highest mortality rate globally in 2020.Nowadays,CC is mainly treated with capecitabine chemotherapy regimen,supplemented by radiotherapy,immunotherapy and targeted therapy,but there are still limitations,so Chinese medicine plays an important role.AIM To investigate the effects of invigorating-spleen and anticancer prescription(ISAP)on body weight,tumor inhibition rate and expression levels of proteins in extracellular-signal-regulated kinase(ERK)/mitogen-activated protein kinase(MAPK)signaling pathway in CC mice model.METHODS The CC mice model were established and the mice were randomly divided into 5 groups,including the control group,capecitabine group,the low-dose,mediumdose and high-dose groups of ISAP,with 8 mice in each group,respectively.After 2 weeks of intervention,the body weight and tumor inhibition rate of mice were observed,and the expression of RAS,ERK,phosphorylated ERK(p-ERK),C-MYC and matrix metalloproteinase 2(MMP2)proteins in the tissues of tumors were detected.RESULTS Compared with the control group,the differences of body weight before and after treatment was much smaller in the groups of ISAP,with the smallest difference in the high-dose group of ISAP,while the capecitabine group had the greatest difference,indicating ISAP had a significant inhibiting effect on the growth of transplanted tumor in mice.The expression of RAS protein was decreased in the low-and medium-dose groups of ISAP,and the change of p-ERK was significant in the medium-and high-dose groups of ISAP.MMP2 protein expression was significantly decreased in both the low-dose and medium-dose groups of ISAP.There were no significant changes in ERK in the ISAP group compared to the capecitabine group,while RAS,MMP2,and C-MYC protein expression were reduced in the ISAP group.The expression level of C-MYC protein decreased after treated with ISAP,and the decrease was the most significant in the medium-dose group of ISAP.CONCLUSION ISAP has a potential inhibiting effect on transplanted tumor in mice,and could maintain the general conditions,physical strength and body weight of mice.The expression levels of RAS,p-ERK,MMP2 and c-myc were also decreased to a certain extent.By inhibiting the expression of upstream proteins,the expression levels of downstream proteins in ERK/MAPK signaling pathway were significantly decreased.Therefore,it can be concluded that ISAP may exert an anti-tumor effect by blocking the ERK/MAPK signaling pathway and inhibiting the expression of MMP2 and c-myc proteins.

Jiawei Wendan decoction affects mitogen-activated protein kinase signal pathway in the hippocampus of depression rats

A previous study from our group showed that Jiawei Wendan decoction inhibits protein expression of interleukin-1β, 2, and 6, as well as plasma neuropeptide Y, P substance and somatostatin in the hippocampus of depression rat models. The present study analyzed the influence of Jiawei Wendan decoction on the mitogen-activated protein kinase signal transduction pathway in the hippocampus. Results demonstrated that Jiawei Wendan decoction effectively upregulated expression of small molecular G proteins, extracellular regulated kinase 1/2, and activated ribosomal S6 kinase protein in the rat hippocampus. In addition, Jiawei Wendan decoction exhibits antidepressant effects similar to fluoxetine. The underlying mechanisms were shown to be dependent on increased mitogen-activated protein kinase signal transduction pathway activity.

Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

Increased expression of mitogen-activated protein kinase and its upstream regulating signal in human gastric cancer

AIM: To investigate the expression of mitogen-activated protein kinases (MAPKs) and its upstream protein kinase in human gastric cancer and to evaluate the relationship between protein levels and clinicopathological parameters. METHODS: Western blot was used to measure the expression of extracellular signal-regulated kinase (ERK)-1, ERK-2, ERK-3, p38 and mitogen or ERK activated protein kinaseMEK-1 proteins in surgically resected gastric carcinoma, adjacent normal mucosa and metastatic lymph nodes from 42 patients. Immunohistochemistry was employed for their localization. RESULTS: Compared with normal tissues, the protein levels of ERK-1 (integral optical density value 159 526?5 760 vs 122 807±65 515, P= 0.001), ERK-2 (168 471±95 051 vs 120 469±72 874, P<0.001), ERK-3 (118 651±71 513 vs 70 934±68 058,P<0.001), P38 (104 776±51 650 vs 82 930±40 392, P= 0.048) and MEK-1 (116 486±45 725 vs 101 434±49 387, P = 0.027) were increased in gastric cancer tissues. Overexpression of ERK-3 was correlated to TNM staging [average ratio of integral optic density (IOD)tumor: IODnormal in TNM I, II, III, IV tumors was 1.43±0.34, 5.08±3.74, 4.99±1.08, 1.44±1.02, n = 42, P= 0.023] and serosa invasion (4.31±4.34 vs 2.00±2.03, P = 0.037). In poorly differentiated cancers (n = 33), the protein levels of ERK-1 and ERK-2 in stage III and IV tumors were higher than those in stage I and II tumors (2.64+3.01 vs 1.01±0.33, P= 0.022; 2.05±1.54 vs1.24±0.40, P= 0.030). Gastric cancer tissues with either lymph node involvement (2.49±2.91 vs1.03±0.36, P= 0.023; 1.98±1.49vs1.24±0.44, P= 0.036) or serosa invasion (2.39±2.82 vs 1.01±0.35, P= 0.022; 1.95±1.44 vs1.14±0.36, P=0.015) expressed higher protein levels of ERK-1 and ERK-2. In Borrmann II tumors, expression of ERK-2 and ERK-3 was increased compared with Borrmann III tumors (2.57±1.86 vs1.23±0.60, P= 0.022; 5.50±5.05 vs1.83±1.21, P= 0.014). Borrmann IV tumors expressed higher p38 protein levels. No statistically significant difference in expression of MAPKs was found when stratified to tumor size or histological grade (P>0.05). Protein levels of ERK-2, ERK-3 and MEK-1 in metastatic lymph nodes were 2-7 folds higher than those in adjacent normal mucosa. The immunohistochemistry demonstrated that ERK-1, ERK-2, ERK-3, p38 and MEK-1 proteins were mainly localized in cytoplasm. The expression of MEK-1 in gastric cancer cells metastasized to lymph nodes was higher than that of the primary site. CONCLUSION: MAPKs, particularly ERK subclass are overexpressed in the majority of gastric cancers. Overexpression of ERKs is correlated to TNM staging, serosa invasion, and lymph node involvement. The overexpression of p38 most likely plays a prominent role in certain morphological subtypes of gastric cancers. MEK-1 is also overexpressed in gastric cancer, particularly in metastatic lymph nodes. Upregulation of MARK signal transduction pathways may play an important role in tumorigenesis and metastatic potential of gastric cancer.

Influence of electroacupuncture on mitogen-activated protein kinase signal transduction in a rat model of cerebral ischemia/reperfusion

Following electroacupuncture at Baihui （DU 20） and Dazhui （DU 14） in a rat model of cerebral ischemia/reperfusion, extracellular-signal-regulated kinase expression in cerebral cortex and corpus striatum, serum glutathione reductase, glutathione peroxidase activity, and serum glutathione content were elevated, and neurobehavioral scores improved. However, these effects were antagonized by mitogen-activated protein kinase inhibitor PD98059. Results indicated that electroacupuncture reversed free radical chain reactions and oxidative stress injury caused by cerebral ischemia/reperfusion, thereby providing neuroprotection. This process could correlate with the mitogen-activated protein kinase signal transduction pathway.

Bacteroides fragilis enterotoxin upregulates heme oxygenase-1 in dendritic cells via reactive oxygen species-,mitogen-activated protein kinase-,and Nrf2-dependent pathway

BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF-secreted toxin(BFT).Dendritic cells(DCs)play an important role in directing the nature of adaptive immune responses to bacterial infection and heme oxygenase-1(HO-1)is involved in the regulation of DC function.AIM To investigate the role of BFT in HO-1 expression in DCs.METHODS Murine DCs were generated from specific pathogen-free C57BL/6 and Nrf2−/−knockout mice.DCs were exposed to BFT,after which HO-1 expression and the related signaling factor activation were measured by quantitative RT-PCR,EMSA,fluorescent microscopy,immunoblot,and ELISA.RESULTS HO-1 expression was upregulated in DCs stimulated with BFT.Although BFT activated transcription factors such as NF-κB,AP-1,and Nrf2,activation of NF-κB and AP-1 was not involved in the induction of HO-1 expression in BFT-exposed DCs.Instead,upregulation of HO-1 expression was dependent on Nrf2 activation in DCs.Moreover,HO-1 expression via Nrf2 in DCs was regulated by mitogenactivated protein kinases such as ERK and p38.Furthermore,BFT enhanced the production of reactive oxygen species(ROS)and inhibition of ROS production resulted in a significant decrease of phospho-ERK,phospho-p38,Nrf2,and HO-1 CONCLUSION These results suggest that signaling pathways involving ROS-mediated ERK and p38 mitogen-activated protein kinases-Nrf2 activation in DCs are required for HO-1 induction during exposure to ETBF-produced BFT.

Mitogen-Activated Protein Kinase Pathways Following Traumatic Brain Injury

The mechanisms underlying the secondary or delayed cell death in the hippocampus and cerebral hemisphere after traumatic brain injury (TBI) have been poorly understood. Recent data suggesting that TBI may have relationship with both an inflammatory and a neurodegenerative factors are also presented. Mitogen-activated protein kinases (MAPK), which play a crucial role in signal transduction, are activated by phosphorylation in response to a variety of mitogenic signals. In this article, we review the clinical and experimental evidence for brain damage after TBI. In addition, the MAPK pathways, closely involved in signal transduction after TBI, which could therefore be a new and potentially effective therapeutic target in TBI. Further investigations are therefore necessary to better understand cerebral traumatic damage and delineate the best practice strategies needed to improve the patient outcomes after TBI.

Downregulation of cold-inducible RNA-binding protein activates mitogen-activated protein kinases and impairs spermatoRenic function in mouse testes

Cold-inducible RNA-binding protein （CIRP） is an RNA-binding protein that is expressed in normal testes and downregulated after heat stress caused by cryptorchidism, varicocele or environmental temperatures. The purpose of this study was to investigate the functions of CIRP in the testes. We employed RNAi technique to knock down the expression of CIRP in the testes, and performed haematoxylin and eosin staining to evaluate morphological changes following knockdown. Germ cell apoptosis was examined by terminal deoxynucleotidal transferase-mediated dUTP nick end labelling （TUNEL） assay, and mitogen-activated protein kinase （MAPK） signalling pathways were investigated by Western blotting to determine the possible mechanism of apoptosis. We found that using siRNA is a feasible and reliable method for knocking down gene expression in the testes. Compared to controls, the mean seminiferous tubule diameter （MSTD） and the thickness of the germ cell layers decreased following siRNA treatment, whereas the percentage of apoptotic seminiferous tubules increased. The p44/p42, p38 and SAPK/JNK MAPK pathways were activated after downregulation of CIRP. In conclusion, we discovered that downregulation of CIRP resulted in increased germ cell apoptosis, possibly viathe activation of the p44/p42, p38 and SAPK/JNK MAPK pathways.

Mitogen-activated protein kinase phosphatase 1 protects PC12 cells from amyloid beta-induced neurotoxicity

The mitogen-activated protein kinase（MAPK） signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1（MKP1） has an inhibitory effect on the p38 MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 sh RNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42（Aβ42）. The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha（TNF-α） and interleukin-1β（IL-1β） m RNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase（JNK） expression levels were assessed using western blot assay. Reactive oxygen species（ROS） levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase d UTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.

Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition

BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

Mitogen activated protein kinase signaling pathways participate in the active principle region of Buyang Huanwu decoction-induced differentiation of bone marrow mesenchymal stem cells

Our preliminary studies confirmed that an active principle region of Buyang Huanwu decoction, comprising alkaloid, polysaccharide, aglycon, glucoside and volatile oil, can induce bone marrow mesenchymal stem cell differentiation into neurons. Mitogen-activated protein kinase signaling was identified as one of the key pathways underlying this differentiation process. The present study shows phosphorylated extracellular signal-regulated protein kinase and phosphorylated p38 protein expression was increased after differentiation. Cellular signaling pathway blocking agents, PD98059 and SB203580, inhibited extracellular signal-regulated protein kinase and p38 in mitogen-activated protein kinase signaling pathways respectively, mRNA and protein expression of the neuronal marker, neuron specific enolase, and neural stem cell marker, nestin, were decreased in bone marrow mesenchymal stem cells after treatment with the active principle region of Buyang Huanwu decoction. Experimental findings indicate that, extracellular signal-regulated protein kinase and p38 in mitogen-activated protein kinase signaling pathways participate in bone marrow mesenchymal stem cell differentiation into neuron-like cells, induced by the active principle region of Buyang Huanwu decoction.

Overinhibition of Mitogen-Activated Protein Kinase Inducing Tau Hyperphosphorylation

To reveal the relationship between mitogen-acti-vated protein kinase (MAPK)and tau phosphorylation, we used different concentration of PD98059, an inhibitor of MEK (MAPKkinase), to treat mice neuroblastma (N2a) cell line for 6 h. It showed that theactivity of MAPKdecreased in a dose-dependent manner. But Western blot and immunofluo-rescence revealed that justwhen the cells were treated with 16 mu mol/L PD98059, tau was hyperphosphorylated at Ser396/ 404 andSerl99/202 sites. We obtained the conclusion that overinhibited MAPK induced tauhyperphosphorylation at Ser396/404 and Serl99/202 sites.

Marsdenia tenacissima extract induces G_0/G_1 cell cycle arrest in human esophageal carcinoma cells by inhibiting mitogen-activated protein kinase(MAPK) signaling pathway

Marsdenia tenacissima extract(MTE, trade name: Xiao-Ai-Ping injection) is an extract of a single Chinese plant medicine. It has been used for the treatment of cancer in China for decades, especially for esophageal cancer and other cancers in the digestive tract. In the present study, the potential mechanism for MTE's activity in esophageal cancer was explored. The effects of MTE on the proliferation of human esophageal cancer cells(KYSE150 and Eca-109) were investigated by the MTT assay, the Brd U(bromodeoxyuridine) incorporation immunofluorescence assay, and flow cytometric analysis. MTE inhibited cell proliferation through inducing G0/G1 cell cycle arrest in KYSE150 and Eca-109. Western blot analysis was employed to determine protein levels in the MTE treated cells. Compared with the control cells, the expression levels of the cell cycle regulatory proteins cyclin D1/D2/D3, cyclin E1, CDK2/4/6(CDK: cyclin dependent kinase), and p-Rb were decreased significantly in the cells treated with MTE at 40 mg·m L-1. In addition, MTE had an inhibitory effect on the MAPK(mitogen-activated protein kinase) signal transduction pathway, including ERK(extracellular signal-regulated kinase), JNK(c-Jun N-terminal kinase), and p38 MAPK. Moreover, MTE showed little additional effects on the regulation of cyclin D1/D3, CDK4/6, and p-Rb when the ERK pathway was already inhibited by the specific ERK inhibitor U0126. In conclusion, these data suggest that MTE inhibits human esophageal cancer cell proliferation through regulation of cell cycle regulatory proteins and the MAPK signaling pathways, which is probably mediated by the inhibition of ERK activation.

Interleukin-1 beta up-regulates tissue inhibitor of matrix metalloproteinase-1 mRNA and phosphorylation of c-jun N-terminal kinase and p38 in hepatic stellate cells

AIM： To study the relationship between interleukin-lbeta （IL-1β） up-regulating tissue inhibitor of matrix metalloproteinase-1 （TIMMP-1） mRNA expression and phosphorylation of both c-jun N-terminal kinase （INK） and p38 in rat heffatic stellate cells （HSC）. METHODS： RT-PCR was performed to measure the expression of TIMMP-1 mRNA in rat HSC. Western blot was performed to measure IL-1β-induced JNK and p38 activities in rat HSC. RESULTS： TIMMP-1 mRNA expression （1.191± 0.079） was much higher after treatment with IL-1β （10 ng/mL） for 24 h than in control group （0.545±0.091） （P〈0.01）. IL-1β activated INK and p38 in a time-dependent manner. After stimulation with IL-1β for 0, 5, 15, 30, 60 and 120 min, the INK activity was 0.982±0.299, 1.501±0.720, 2.133±0.882, 3.360±0.452, 2.181±0.789, and 1.385 ± 0.368, respectively. There was a significant difference in JNK activity at 15 min （P〈 0.01）, 30 min （P〈 0.01） and 60 min （P〈0.01） in comparison to that at 0 min. The p38 activity was 1.061±0.310, 2.050±0.863, 2.380±0.573, 2.973±0.953, 2.421±0.793, and 1.755 ± 0.433 at the 6 time points （0, 5, 15, 30, 60 and 120 min） respectively. There was a significant difference in p38 activity at 5 min （P〈0.05）, 15 min （P〈0.01）, 30 min （P〈0.01） and 60 min （P〈0.01） compared to that at 0 min. TIMMP-1 mRNA expression trended to decrease in 3 groups pretreated with different concentrations of SP600125 （10 μmol/L, 1.022±0.113; 20 μmol/L, 0.869±0.070; 40 μmol/L, 0.666±0.123）. Their decreases were all significant （P〈0.05, P〈0.01, P〈0.01） in comparison to control group （without SP600125 treatment, 1.163±0.107）. In the other 3 groups pretreated with different concentrations of SB203580 （10 μmol/L, 1.507±0.099; 20 μmol/L, 1.698±0.107; 40 μmol/L, 1.857±0.054）, the expression of TIMMP-1 mRNA increased. Their levels were higher than those in the control group （without SB203580 treatment, 1.027 ± 0.061） with a significant statistical significance （P〈 0.01）. CONCLUSION： IL-1β has a direct action on hepatic fibrosis by up-regulating TIMMP-1 mRNA expression in ratessionin in rate HSC.JNK and p38 mitogen-activated protein kinases （MAPKs） are involved in IL-1β-induced TIMMP-1 gene expression, and play a distinct role in this process, indicating that p38 and .INK pathways cooperatively mediate TIMP-1 mRNA expression in rat HSC.

PBX3 promotes migration and invasion of colorectal cancer cells via activation of MAPK/ERK signaling pathway

AIM: To investigate the role of pre-B-cell leukemia homeobox (PBX)3 in migration and invasion of colorectal cancer (CRC) cells.

Electroacupuncture stimulating Zusanli(ST36),Sanyinjiao(SP6)in mice with collagen-induced arthritis leads to adenosine A2A receptor-mediated alteration of p38αmitogen-activated protein kinase signaling and inhibition of osteoclastogenesis

OBJECTIVE:To observe the effect of electroacupuncture(EA)stimulating Zusanli(ST36),Sanyinjiao(SP6)on inhibition of osteoclastogenesis and the role of the adenosine A2A receptor(A2AR)and the p38αMitogen-Activated Protein Kinase(MAPK)signaling pathway in mediating this effect.METHODS:Mice with collagen induced arthritis(CIA)received different treatments.Immunohistochemistry and western blotting were used to determine the levels of multiple signaling molecules in these joints[receptor activator of nuclear transcription factor-κB(NF-κB)ligand(RANKL),receptor activator of NF-κB(RANK),tumor necrosis factor receptor associated factor 6(TRAF6),p38α,NF-κB,and nuclear factor of activated T cells C1(NFATc1)].Osteoclasts were identified using tartrate-resistant acid phosphatase(TRAP)staining.RESULTS:The immunohistochemistry results indicated upregulation of p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced levels in the CIA-EA group.Western blotting indicated upregulation of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced expression in the CIA-EA group.Osteoclasts were more abundant in the CIA-control and CIA-EA-SCH58261 groups than in the CIA-EA group.CONCLUSIONS:EA treatment enhanced the A2AR activity and inhibited osteoclast formation by inhibition of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1.SCH58261 reversed the effect of EA.These results suggest that EA regulated p38α-MAPK signaling by increasing A2AR activity,which inhibited osteoclastogenesis.

Down-regulation of HIV-1 Infection by Inhibition of the MAPK Signaling Pathway

The human immunodeficiency virus type 1 （HIV-1） can interact with and exploit the host cellular machinery to replicate and propagate itself. Numerous studies have shown that the Mitogen-activated protein kinase （MAPK） signal pathway can positively regulate the replication of HIV-1, but exactly how each MAPK pathway affects HIV-1 infection and replication is not understood. In this study, we used the Extracellular signal-regulated kinase （ERK） pathway inhibitor, PD98059, the Jun N-terminal kinase （JNK） pathway inhibitor, SP600125, and the p38 pathway inhibitor, SB203580, to investigate the roles of these pathways in HIV-1 replication. We found that application of PD98059 results in a strong VSV-G pseudotyped HIV-1NL4-3 luciferase reporter virus and HIV-1NL4-3 virus inhibition activity. In addition, SB203580 and SP600125 also elicited marked VSV-G pseudotyped HIV-INL4-3 luciferase reporter virus inhibition activity but no HIV-1NL4-3 virus inhibition activity. We also found that SB203580 and SP600125 can enhance the HIV-1 inhibition activity of PD98059 when cells were treated with all three MAPK pathway inhibitors in combination. Finally, we show that HIV-1 virus inhibition activity of the MAPK pathway inhibitors was the result of the negative regulation of HIV-1 LTR promoter activity.

Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional activities.In this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 cells.All flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and P65.The expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable effects.Furthermore,the intracellular metabolic conditions of the fl avonoids were also evaluated.

γ-Aminobutyric acid alleviates litchi thaumatin-like protein-induced inflammation and reduces gut microbial translocation

Previous research reported litchi thaumatin-like protein(LcTLP)could lead to inflammation,which is a factor causing the adverse reactions after excessive intake of litchi.As a main amino acid in litchi pulp,γ-aminobutyric acid(GABA)was found with anti-inflammatory effect.Therefore,this study aimed to investigate the effects of GABA on LcTLP-induced inflammation through RAW264.7 macrophages and C57BL mice models.In vitro study showed GABA could effectively regulate the level of inflammatory cytokines(interleukin(IL)-1β,IL-6,IL-10,and prostaglandin E2)and Ca2+in cells,and inhibit the phosphorylation of p65,IκB,p38,c-Jun N-terminal kinase(JNK)and extracellular signal-regulated kinase(ERK).These results indicate GABA alleviated inflammation through nuclear factor-κB and mitogen-activated protein kinase pathway signaling pathways.In vivo experiment was performed to verify the anti-inflammatory effect of GABA,and the results demonstrated that GABA reduced the inflammation and oxidative stress in the liver of LcTLP-treated mice,as it down-regulated the pro-inflammatory cytokines,malondialdehyde,aspartate transferase,and alanine transaminase.The relative expression of phosphorylated p38,JNK and ERK in mice liver with GABA treatment were reduced to 65%,39%and 80%of the control group,respectively.Furthermore,GABA treatment enriched probiotic bacteria and decreased pathogenic bacteria in mice gut,which reveals GABA could effectively reduce the translocation of gut microbiota.

NOX4 promotes tumor progression through the MAPK-MEK1/2-ERK1/2 axis in colorectal cancer

BACKGROUND Metabolic reprogramming plays a key role in cancer progression and clinical outcomes;however,the patterns and primary regulators of metabolic reprogramming in colorectal cancer(CRC)are not well understood.AIM To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4)in promoting progression of CRC.METHODS We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes.Consensus clustering was used to cluster CRC based on dysregulated metabolic genes.A prediction model was constructed based on survival-related metabolic genes.Sphere formation,migration,invasion,proliferation,apoptosis and clone formation was used to evaluate the biological function of NOX4 in CRC.mRNA sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor cells.In vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor growth.RESULTS We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic genes.Among these genes,NOX4 was highly expressed in tumor tissues and correlated with worse survival.In vitro,NOX4 overexpression induced clone formation,migration,invasion,and stemness in CRC cells.Furthermore,RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling pathway.Trametinib,a MEK1/2 inhibitor,abolished the NOX4-mediated tumor progression.In vivo,NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis,whereas trametinib treatment can reversed the metastasis.CONCLUSION Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis,suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.