Rosavin suppresses osteoclastogenesis in vivo and in vitro by blocking the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways

ABSTRACT Chikungunya virus (CHIKV) has infected millions of people in the tropical and subtropical regions since its reemergence in the last decade. We recently identified the nontoxic plant alkaloid berberine as an antiviral substance against CHIKV in a high-throughput screen. Here, we show that berberine is effective in multiple cell types against a variety of CHIKV strains, also at a high multiplicity of infection, consolidating the potential of berberine as an antiviral drug. We excluded any effect of this compound on virus entry or on the activity of the viral replicase. A human phosphokinase array revealed that CHIKV infection specifically activated the major mitogen-activated protein kinase (MAPK) signaling pathways extracellular signal-related kinase (ERK), p38 and c-Jun NH 2 -terminal kinase (JNK). Upon treatment with berberine, this virus-induced MAPK activation was markedly reduced. Subsequent analyses with specific inhibitors of these kinases indicated that the ERK and JNK signaling cascades are important for the generation of progeny virions. In contrast to specific MAPK inhibitors, berberine lowered virus-induced activation of all major MAPK pathways and resulted in a stronger reduction in viral titers. Further, we assessed the in vivo efficacy of berberine in a mouse model and measured a significant reduction of CHIKV-induced inflammatory disease. In summary, we demonstrate the efficacy of berberine as a drug against CHIKV and highlight the importance of the MAPK signaling pathways in the alphavirus infectious cycle. IMPORTANCE Chikungunya virus (CHIKV) is a mosquito-borne virus that causes severe and persistent muscle and joint pain and has recently spread to the Americas. No licensed drug exists to counter this virus. In this study, we report that the alkaloid berberine is antiviral against different CHIKV strains and in multiple human cell lines. We demonstrate that berberine collectively reduced the virus-induced activation of cellular mitogen-activated protein kinase signaling. The relevance of these signaling cascades in the viral life cycle was emphasized by specific inhibitors of these kinase pathways, which decreased the production of progeny virions. Berberine significantly reduced CHIKV-induced inflammatory disease in a mouse model, demonstrating efficacy of the drug in vivo . Overall, this work makes a strong case for pursuing berberine as a potential anti-CHIKV therapeutic compound and for exploring the MAPK signaling pathways as antiviral targets against alphavirus infections.

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Ras/Mitogen-Activated Protein Kinase Signaling Activates Ets-1 and Ets-2 by CBP/p300 Recruitment

Molecular and Cellular Biology ◽

10.1128/mcb.24.24.10954-10964.2004 ◽

2004 ◽

Vol 24 (24) ◽

pp. 10954-10964 ◽

Cited By ~ 138

Author(s):

Charles E. Foulds ◽

Mary L. Nelson ◽

Adam G. Blaszczak ◽

Barbara J. Graves

Keyword(s):

Transcription Factors ◽

Protein Kinase ◽

Direct Interaction ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Creb Binding Protein ◽

Mitogen Activated Protein ◽

P300 Binding

ABSTRACT Cell signaling affects gene expression by regulating the activity of transcription factors. Here, we report that mitogen-activated protein kinase (MAPK) phosphorylation of Ets-1 and Ets-2, at a conserved site N terminal to their Pointed (PNT) domains, resulted in enhanced transactivation by preferential recruitment of the coactivators CREB binding protein (CBP) and p300. We discovered this phosphorylation-augmented interaction in an unbiased affinity chromatography screen of HeLa nuclear extracts by using either mock-treated or ERK2-phosphorylated ETS proteins as ligands. Binding between purified proteins demonstrated a direct interaction. Both the phosphoacceptor site, which lies in an unstructured region, and the PNT domain were required for the interaction. Minimal regions that were competent for induced CBP/p300 binding in vitro also supported MAPK-enhanced transcription in vivo. CBP coexpression potentiated MEK1-stimulated Ets-2 transactivation of promoters with Ras-responsive elements. Furthermore, CBP and Ets-2 interacted in a phosphorylation-enhanced manner in vivo. This study describes a distinctive interface for a transcription factor-coactivator complex and demonstrates a functional role for inducible CBP/p300 binding. In addition, our findings decipher the mechanistic link between Ras/MAPK signaling and two specific transcription factors that are relevant to both normal development and tumorigenesis.

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Combined VEGFR and MAPK pathway inhibition in angiosarcoma

Scientific Reports ◽

10.1038/s41598-021-88703-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Michael J. Wagner ◽

Yasmin A. Lyons ◽

Jean H. Siedel ◽

Robert Dood ◽

Archana S. Nagaraja ◽

...

Keyword(s):

Protein Kinase ◽

Mapk Pathway ◽

Combined Treatment ◽

Mek Inhibitor ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

In Vivo Model ◽

Mitogen Activated Protein

AbstractAngiosarcoma is an aggressive malignancy of endothelial cells that carries a high mortality rate. Cytotoxic chemotherapy can elicit clinical responses, but the duration of response is limited. Sequencing reveals multiple mutations in angiogenesis pathways in angiosarcomas, particularly in vascular endothelial growth factor (VEGFR) and mitogen-activated protein kinase (MAPK) signaling. We aimed to determine the biological relevance of these pathways in angiosarcoma. Tissue microarray consisting of clinical formalin-fixed paraffin embedded tissue archival samples were stained for phospho- extracellular signal-regulated kinase (p-ERK) with immunohistochemistry. Angiosarcoma cell lines were treated with the mitogen-activated protein kinase kinase (MEK) inhibitor trametinib, pan-VEGFR inhibitor cediranib, or combined trametinib and cediranib and viability was assessed. Reverse phase protein array (RPPA) was performed to assess multiple oncogenic protein pathways. SVR angiosarcoma cells were grown in vivo and gene expression effects of treatment were assessed with whole exome RNA sequencing. MAPK signaling was found active in over half of clinical angiosarcoma samples. Inhibition of MAPK signaling with the MEK inhibitor trametinib decreased the viability of angiosarcoma cells. Combined inhibition of the VEGF and MAPK pathways with cediranib and trametinib had an additive effect in in vitro models, and a combinatorial effect in an in vivo model. Combined treatment led to smaller tumors than treatment with either agent alone. RNA-seq demonstrated distinct expression signatures between the trametinib treated tumors and those treated with both trametinib and cediranib. These results indicate a clinical study of combined VEGFR and MEK inhibition in angiosarcoma is warranted.

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Alantolactone Attenuates Cisplatin-Induced Nephrotoxicity by Inhibiting Mitogen-Activated Protein Kinase and Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B Cells Signaling Pathways

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.18:96-101 ◽

2019 ◽

Vol 18 (1) ◽

pp. 96-101

Author(s):

Hao Yanyan ◽

Zou Xiaojing ◽

Xiang Xielong

Keyword(s):

B Cells ◽

Protein Kinase ◽

Light Chain ◽

Mitogen Activated Protein Kinase ◽

Nuclear Factor ◽

Kappa Light Chain ◽

Nuclear Factor Kappa ◽

Mitogen Activated Protein ◽

Light Chain Enhancer ◽

Activated B Cells

Cisplatin is one of the potent chemotherapeutic drugs widely used for the treatment of various types of cancers. However, nephrotoxicity severely restricts the use of this anticancer drug. Alantolactone is a sesquiterpene lactone that exerts a number of biologic properties such as anti-inflammatory, anti-oxidant, and antibacterial activities. This study investigated the role of alantolactone in cisplatin-induced nephrotoxicity and the underlying mechanism. Results showed that alantolactone significantly increased the viability of human renal tubular epithelial cells (HK-2 cells) exposed to cisplatin. Besides, alantolactone inhibited the expression of tumor necrosis factor-a, interleukin-1β, and interleukin-6, as well as the production of nitric oxide. Moreover, alantolactone inhibited the cisplatin-induced increased expression of p-p38/p38, p-JNK/JNK, p-ERK/ERK, and p-p65/p65, which is related to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), p38, c-Jun N-terminal kinase, and the mitogen-activated protein kinase (MAPK) signaling pathway. This study suggests that alantolactone attenuates cisplatin-induced nephrotoxicity through its anti-inflammatory and antioxidant properties. Thus, alatolactone could be a potential candidate compound for cisplatin-based adjuvant chemotherapy.

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