The Role of MAPK's Signaling in Mediating ApoE4-Driven Pathology In Vivo

2019 ◽  
Vol 16 (4) ◽  
pp. 281-292 ◽  
Author(s):  
Shiran Salomon-Zimri ◽  
Amit Koren ◽  
Ariel Angel ◽  
Tali Ben-Zur ◽  
Daniel Offen ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Adeno Associated Virus ◽  
Immunoblot Assay ◽  
Total Level ◽  
Mitogen Activated Protein

Background: Alzheimer's Disease (AD) is associated with impairments in key brain Mitogen- Activated Protein Kinase (MAPK) signaling cascades including the p38, c-Jun N-terminal kinase (JNK), ERK and Akt pathways. Apolipoprotein E4 (ApoE4) is the most prevalent genetic risk factor of AD. Objectives: To investigate the extent to which the MAPK signaling pathway plays a role in mediating the pathological effects of apoE4 and can be reversed by experimental manipulations. Methods: Measurements of total level and activation of MAPK signaling pathway factors, obtained utilizing immunoblot assay of hippocampal tissues from naïve and viral-treated apoE3 and apoE4 targeted replacement mice. Methods: Measurements of total level and activation of MAPK signaling pathway factors, obtained utilizing immunoblot assay of hippocampal tissues from naïve and viral-treated apoE3 and apoE4 targeted replacement mice. Results: ApoE4 mice showed robust activation of the stress related p38 and JNK pathways and a corresponding decrease in Akt activity, which is coupled to activation of GSK3β and tau hyperphosphorylation. There was no effect on the ERK pathway. We have previously shown that the apoE4- related pathology, namely; accumulation of Aβ, hyper-phosphorylated tau, synaptic impairments and decreased VEGF levels can be reversed by up-regulation of VEGF level utilizing a VEGF-expressing adeno-associated virus. Utilizing this approach, we assessed the extent to which the AD-hallmark and synaptic pathologies of apoE4 are related to the corresponding MAPK signaling effects. This revealed that the reversal of the apoE4-driven pathology via VEGF treatment was associated with a reversal of the p38 and Akt related effects. Conclusion: Taken together, these results suggest that the p38 and Akt pathways play a role in mediating the AD-related pathological effects of apoE4 in the hippocampus.

scholarly journals Adenosine Triphosphate Activates Mitogen-Activated Protein Kinase in Human Granulosa-Luteal Cells*

Endocrinology ◽  
2001 ◽  
Vol 142 (4) ◽  
pp. 1554-1560 ◽  
Author(s):  
Chen-Jei Tai ◽  
Sung Keun Kang ◽  
Chii-Ruey Tzeng ◽  
Peter C. K. Leung
Keyword(s):  
Protein Kinase ◽  
Signaling Pathway ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Intracellular Camp ◽  
Human Ovary ◽  
Luteal Cells ◽  
Mitogen Activated Protein

Abstract ATP has been shown to activate the phospholipase C/diacylglycerol/protein kinase C (PKC) pathway. However, little is known about the downstream signaling events. The present study was designed to examine the effect of ATP on activation of the mitogen-activated protein kinase (MAPK) signaling pathway and its physiological role in human granulosa-luteal cells. Western blot analysis, using a monoclonal antibody that detected the phosphorylated forms of extracellular signal-regulated kinase-1 and -2 (p42mapk and p44 mapk, respectively), demonstrated that ATP activated MAPK in a dose- and time-dependent manner. Treatment of the cells with suramin (a P2 purinoceptor antagonist), neomycin (a phospholipase C inhibitor), staurosporin (a PKC inhibitor), or PD98059 (an MAPK/ERK kinase inhibitor) significantly attenuated the ATP-induced activation of MAPK. In contrast, ATP-induced MAPK activation was not significantly affected by pertussis toxin (a Gi inhibitor). To examine the role of Gs protein, the intracellular cAMP level was determined after treatment with ATP or hCG. No significant elevation of intracellular cAMP was noted after ATP treatment. To determine the role of MAPK in steroidogenesis, human granulosa-luteal cells were treated with ATP, hCG, or ATP plus hCG in the presence or absence of PD98059. RIA revealed that ATP alone did not significantly affect the basal progesterone concentration. However, hCG-induced progesterone production was reduced by ATP treatment. PD98059 reversed the inhibitory effect of ATP on hCG-induced progesterone production. To our knowledge, this is the first demonstration of ATP-induced activation of the MAPK signaling pathway in the human ovary. These results support the idea that the MAPK signaling pathway is involved in mediating ATP actions in the human ovary.

scholarly journals The Ebola virus soluble glycoprotein contributes to viral pathogenesis by activating the MAP kinase signaling pathway

2021 ◽  
Vol 17 (9) ◽  
pp. e1009937
Author(s):  
Wakako Furuyama ◽  
Kyle Shifflett ◽  
Heinz Feldmann ◽  
Andrea Marzi
Keyword(s):  
Signaling Pathway ◽  
Ebola Virus ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Hek293 Cells ◽  
Huh7 Cells ◽  
Mitogen Activated Protein

Ebola virus (EBOV) expresses three different glycoproteins (GPs) from its GP gene. The primary product, soluble GP (sGP), is secreted in abundance during infection. EBOV sGP has been discussed as a potential pathogenicity factor, however, little is known regarding its functional role. Here, we analyzed the role of sGP in vitro and in vivo. We show that EBOV sGP has two different functions that contribute to infectivity in tissue culture. EBOV sGP increases the uptake of virus particles into late endosomes in HEK293 cells, and it activates the mitogen-activated protein kinase (MAPK) signaling pathway leading to increased viral replication in Huh7 cells. Furthermore, we analyzed the role of EBOV sGP on pathogenicity using a well-established mouse model. We found an sGP-dependent significant titer increase of EBOV in the liver of infected animals. These results provide new mechanistic insights into EBOV pathogenicity and highlight EBOV sGP as a possible therapeutic target.

Inhibition of miR-200c Expression Promotes Activation of Extracellular Signal-Regulated Kinase (ERK)/ Mitogen-Activated Protein Kinase (MAPK) Signaling Pathway and Inhibits Osteogenic Differentiation in Osteoporosis Mice

2020 ◽  
Vol 10 (2) ◽  
pp. 163-168
Author(s):  
Sheng Wang ◽  
Zhonghan Min ◽  
Run Gu ◽  
Zhongwei Yu ◽  
Pingquan Chen ◽  
...  
Keyword(s):  
Osteogenic Differentiation ◽  
Signaling Pathway ◽  
Mapk Signaling ◽  
Bone Diseases ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Erk Mapk ◽  
Mitogen Activated Protein ◽  
Marrow Mesenchymal Stem Cells ◽  
Sirna Group

During OP bone metabolism, activated MAPK signaling can promote the proliferation and differentiation of osteoclasts. miRNAs involve in bone diseases. Our study aimed to evaluate miR-200c’s effect on ERK/MAPK signaling pathway in OP. miR-200c expression in OP mice and normal mice was detected by qPCR. BMSCs were cultured and transfected with siRNA to establish a miR-200c knockout model. Flow cytometry was used to detect cell apoptosis and ERK/MAPK signaling protein was detected by Western blot. miR-200c expression in OP mice was significantly lower than that in normal mice. Bone marrow mesenchymal stem cells (BMSCs) contain a large amount of siRNA particles under a fluorescence microscope. siRNA transfection can effectively inhibit miR-200c expression without difference of BMSCs apoptosis between miR-200c siRNA group and NC group. However, ERK1/2 and P38 expression in experimental group were significantly higher than those in NC siRNA group with reduced ALP activity. In addition, BMSCs osteogenic differentiation was further diminished when miR-200c expression was inhibited. miR-200c expression is lower in OP mice. miR-200c siRNA inhibits BMSCs osteogenic differentiation via ERK/MAPK signaling, thereby promoting OP progression.

scholarly journals Silencing of SPARC represses heterotopic ossification via inhibition of the MAPK signaling pathway

2019 ◽  
Vol 39 (11) ◽  
Author(s):  
Qianjun Wang ◽  
Qianqian Yang ◽  
Ali Zhang ◽  
Zhiqiang Kang ◽  
Yingsheng Wang ◽  
...  
Keyword(s):  
Heterotopic Ossification ◽  
Signaling Pathway ◽  
Molecular Mechanisms ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Loss Of Function ◽  
Alp Activity ◽  
Mechanistic Investigation

Abstract Heterotopic ossification (HO), the pathologic formation of extraskeletal bone, can be disabling and lethal. However, the underlying molecular mechanisms were largely unknown. The present study aimed to clarify the involvement of secreted protein acidic and rich in cysteine (SPARC) and the underlying mechanism in rat model of HO. The mechanistic investigation on roles of SPARC in HO was examined through gain- and loss-of-function approaches of SPARC, with alkaline-phosphatase (ALP) activity, mineralized nodules, and osteocalcin (OCN) content measured. To further confirm the regulatory role of SPARC, levels of mitogen-activated protein kinase (MAPK) signaling pathways-related proteins (extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), p38, nuclear factor κ-B (NF-κB), and IkB kinase β (IKKβ)) were determined. Bone marrow mesenchymal stem cells were treated with pathway inhibitor to investigate the relationship among SPARC, MAPK signaling pathway, and HO. The results suggested that SPARC expression was up-regulated in Achilles tendon tissues of HO rats. Silencing of SPARC could decrease phosphorylation of ERK, JNK, p38, NF-κB, and IKKβ. Additionally, silencing of SPARC or inhibition of MAPK signaling pathway could reduce the ALP activity, the number of mineralized nodules, and OCN content, thus impeding HO. To sum up, our study identifies the inhibitory role of SPARC gene silencing in HO via the MAPK signaling pathway, suggesting SPARC presents a potential target for HO therapy.

scholarly journals Chicken avian β-defensin 8 modulates immune response via the mitogen-activated protein kinase signaling pathways in a chicken macrophage cell line

2019 ◽  
Author(s):  
Yeojin Hong ◽  
Thu Thao Pham ◽  
Jiae Lee ◽  
Hyun S. Lillehoj ◽  
Yeong Ho Hong
Keyword(s):  
Protein Kinase ◽  
Signaling Pathway ◽  
Proinflammatory Cytokines ◽  
Interferon Γ ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Macrophage Cell ◽  
Mitogen Activated Protein ◽  
Chicken Macrophage

Abstract Background Defensins are antimicrobial peptides composed of three conserved disulfide bridges, a β-sheet, and both hydrophobic and cationic amino acids. In this study, we aimed to demonstrate the immunomodulation role of avian β-defensin 8 (AvBD8) in a chicken macrophage cell line.Results Chicken AvBD8 stimulated the expression of proinflammatory cytokines (interleukin (IL)-1β, interferon-γ, and IL-12p40) and chemokines (CCL4, CXCL13, and CCL20) in macrophages. Furthermore, by western blotting and immunocytochemistry, we confirmed that AvBD8 activated the mitogen-activated protein kinase (MAPK) signaling pathway via extracellular regulated kinases 1/2 (ERK1/2) and p38 signaling molecules.Conclusion Overall, AvBD8 plays a crucial role in host defense as not only an antimicrobial peptide, but also an immunomodulator by activating the MAPK signaling pathway and inducing the expression of proinflammatory cytokines and chemokines.

scholarly journals IL-6 Promotes the Proliferation and Immunosuppressive Function of Myeloid-Derived Suppressor Cells via the MAPK Signaling Pathway in Bladder Cancer

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Zhong Zheng ◽  
Xinyi Zheng ◽  
Yiwen Zhu ◽  
Zhixian Yao ◽  
Weiguang Zhao ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Signaling Pathway ◽  
Suppressor Cells ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Myeloid Derived Suppressor Cells ◽  
Mitogen Activated Protein ◽  
Proliferation Ability ◽  
Muscle Invasive

Muscle-invasive bladder cancer (MIBC) is characterized by a highly complex immune environment, which is not well understood. Interleukin-6 (IL-6) is generated and secreted by multifarious types of cells, including tumor cells. This study was aimed at demonstrating that the levels of IL-6 and the number of myeloid-derived suppressor cells (MDSCs), with a positive correlation between them, increased in MIBC tissues, promoting MIBC cell proliferation, especially in patients with recurrence. In coculture analysis, MDSCs, with the stimulation of IL-6, could significantly lower the proliferation ability of CD4+ or CD8+ T lymphocytes. Further, this study demonstrated that IL-6 could upregulate the mitogen-activated protein kinase (MAPK) signaling pathway in MDSCs. The MAPK signaling inhibitor, aloesin, partially reversed the effects of IL-6 on MDSCs. These data suggested that IL-6 promoted MIBC progression by not only accelerating proliferation but also improving the immune suppression ability of MDSCs through activating the MAPK signaling pathway.

Sign in / Sign up

Export Citation Format

Share Document