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Liang J, Cheng L, Feng J, Han Z, Huang C, Xie F, Li Y, Luo X, Wang Q, He J, Chen H. Molecular mechanism of Danshenol C in reversing peritoneal fibrosis: novel network pharmacological analysis and biological validation. BMC Complement Med Ther 2023; 23:361. [PMID: 37833759 PMCID: PMC10571429 DOI: 10.1186/s12906-023-04170-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 09/15/2023] [Indexed: 10/15/2023] Open
Abstract
OBJECTIVE The primary objective of this study is to elucidate the molecular mechanism underlying the reversal of peritoneal fibrosis (PF) by Danshenol C, a natural compound derived from the traditional Chinese medicine Salvia miltiorrhiza. By comprehensively investigating the intricate interactions and signaling pathways involved in Danshenol C's therapeutic effects on PF, we aim to unveil novel insights into its pharmacological actions. This investigation holds the potential to revolutionize the clinical application of Salvia miltiorrhiza in traditional Chinese medicine, offering promising new avenues for the treatment of PF and paving the way for evidence-based therapeutic interventions. METHODS Firstly, we utilized the YaTCM database to retrieve the structural formula of Danshenol C, while the SwissTargetPrediction platform facilitated the prediction of its potential drug targets. To gain insights into the genetic basis of PF, we acquired the GSE92453 dataset and GPL6480-9577 expression profile from the GEO database, followed by obtaining disease-related genes of PF from major disease databases. R software was then employed to screen for DEG associated with PF. To explore the intricate interactions between Danshenol C's active component targets, we utilized the String database and Cytoscape3.7.2 software to construct a PPI network. Further analysis in Cytoscape3.7.2 enabled the identification of core modules within the PPI network, elucidating key targets and molecular pathways critical to Danshenol C's therapeutic actions. Subsequently, we employed R to perform GO and KEGG pathway enrichment analyses, providing valuable insights into the functional implications and potential biological mechanisms of Danshenol C in the context of PF. To investigate the binding interactions between the core active components and key targets, we conducted docking studies using Chem3D, autoDock1.5.6, SYBYL2.0, and PYMOL2.4 software. We applied in vivo and in vitro experiments to prove that Danshenol C can improve PF. In order to verify the potential gene and molecular mechanism of Danshenol C to reverse PF, we used quantitative PCR, western blot, and apoptosis, ensuring robust and reliable verification of the results. RESULTS ① Wogonin, sitosterol, and Signal Transducer and Activator of Transcription 5 (STAT5) emerged as the most significant constituents among the small-molecule active compounds and gene targets investigated. ②38 targets intersected with the disease, among which MAPK14, CASP3, MAPK8 and STAT3 may be the key targets; The results of GO and KEGG analysis showed that there was a correlation between inflammatory pathway and Apoptosis. ④Real-time PCR showed that the mRNA expressions of MAPK8 (JNK1), MAPK14 (P38) and STAT3 were significantly decreased after Danshenol C treatment (P < 0.05), while the mRNA expression of CASP3 was significantly increased (P < 0.05)⑤Western blot showed that protein expressions of CASP3 and MAPK14 were significantly increased (P < 0.05), while the expression of STAT3 and MAPK8 was decreased after Danshenol C treatment (P < 0.05). ⑥There was no significant difference in flow analysis of apoptosis among groups. CONCLUSION The findings suggest that Danshenol C may modulate crucial molecular pathways, including the MAPK, Apoptosis, Calcium signaling, JAK-STAT signaling, and TNF signaling pathways. This regulation is mediated through the modulation of core targets such as STAT3, MAPK14, MAPK8, CASP3, and others. By targeting these key molecular players, Danshenol C exhibits the potential to regulate cellular responses to chemical stress and inflammatory stimuli. The identification of these molecular targets and pathways represents a significant step forward in understanding the molecular basis of Danshenol C's therapeutic effects in PF. This preliminary exploration provides novel avenues for the development of anti-PF treatment strategies and the discovery of potential therapeutic agents. By targeting specific core targets and pathways, Danshenol C opens up new possibilities for the development of more effective and targeted drugs to combat PF. These findings have the potential to transform the landscape of PF treatment and offer valuable insights for future research and drug development endeavors.
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Affiliation(s)
- Jiabin Liang
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lulu Cheng
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jie Feng
- Radiology Department of Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Zeping Han
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Chen Huang
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
- Medical Imaging Institute of Panyu, Guangzhou, China
| | - Fangmei Xie
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yongsheng Li
- Guangzhou Municipality Tianhe Nuoya Bio-Engineering Co., Ltd, Guangzhou, China
| | - Xun Luo
- Kerry Rehabilitation Medicine Research Institute, Shenzhen, China
| | - Qingmei Wang
- Stroke Biological Recovery Laboratory, Teaching Affiliate of Harvard Medical School, Spaulding Rehabilitation Hospital, Charlestown, MA, USA
| | - Jinhua He
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Hanwei Chen
- Guangzhou Panyu Central Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China.
- Medical Imaging Institute of Panyu, Guangzhou, China.
- Panyu Health Management Center (Panyu Rehabilitation Hospital), Guangzhou, China.
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Yan F, Zhao Q, Li Y, Zheng Z, Kong X, Shu C, Liu Y, Shi Y. The role of oxidative stress in ovarian aging: a review. J Ovarian Res 2022; 15:100. [PMID: 36050696 PMCID: PMC9434839 DOI: 10.1186/s13048-022-01032-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 08/21/2022] [Indexed: 11/29/2022] Open
Abstract
Ovarian aging refers to the process by which ovarian function declines until eventual failure. The pathogenesis of ovarian aging is complex and diverse; oxidative stress (OS) is considered to be a key factor. This review focuses on the fact that OS status accelerates the ovarian aging process by promoting apoptosis, inflammation, mitochondrial damage, telomere shortening and biomacromolecular damage. Current evidence suggests that aging, smoking, high-sugar diets, pressure, superovulation, chemotherapeutic agents and industrial pollutants can be factors that accelerate ovarian aging by exacerbating OS status. In addition, we review the role of nuclear factor E2-related factor 2 (Nrf2), Sirtuin (Sirt), mitogen-activated protein kinase (MAPK), protein kinase B (AKT), Forkhead box O (FoxO) and Klotho signaling pathways during the process of ovarian aging. We also explore the role of antioxidant therapies such as melatonin, vitamins, stem cell therapies, antioxidant monomers and Traditional Chinese Medicine (TCM), and investigate the roles of these supplements with respect to the reduction of OS and the improvement of ovarian function. This review provides a rationale for antioxidant therapy to improve ovarian aging.
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Affiliation(s)
- Fei Yan
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Qi Zhao
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Ying Li
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Zhibo Zheng
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Xinliang Kong
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Chang Shu
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China
| | - Yanfeng Liu
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China.
| | - Yun Shi
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, People's Republic of China.
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3
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Overview of signal transduction between LL37 and bone marrow-derived MSCs. J Mol Histol 2022; 53:149-157. [DOI: 10.1007/s10735-021-10048-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 12/06/2021] [Indexed: 12/27/2022]
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4
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Zhang S, Li Y, Tu Y. Lidocaine attenuates CFA-induced inflammatory pain in rats by regulating the MAPK/ERK/NF-κB signaling pathway. Exp Ther Med 2021; 21:211. [PMID: 33500701 PMCID: PMC7818540 DOI: 10.3892/etm.2021.9643] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/08/2020] [Indexed: 12/11/2022] Open
Abstract
Lidocaine is a commonly used local anesthetic that also confers analgesic effects, resistance to hyperalgesia and anti-inflammatory properties. The present study aimed to explore the effects of lidocaine on complete Freund's adjuvant (CFA)-induced inflammatory pain. In the present study, rats were subcutaneously injected with CFA to investigate the molecular mechanisms associated with lidocaine in an inflammation-induced pain model. Firstly, CFA was subcutaneously injected into the paws of Sprague-Dawley rats, following which lidocaine or saline and the ERK agonist recombinant human epidermal growth factor (rh-EGF) were injected via the tail vein. Rat behavior was then assessed at 0 and 4 h, 1, 4, 7 and 14 days after CFA treatment. Proinflammatory cytokine levels in the serum were measured using ELISA. Western blotting was performed to detect the protein levels of phosphorylated (p)-ERK1/2, ERK1/2 and NF-κB subunits p-p65 and p65. Reverse transcription-quantitative PCR was used to measure the mRNA expression of ERK1/2 and p65 in rat spinal cord tissues. The results showed that injection of CFA significantly reduced the mechanical withdrawal threshold, thermal withdrawal latency and the frequency of responses to cold stimulation in rats, whilst promoting tumor necrosis factor-α, interleukin (IL)-1β, IL-6 levels in addition to ERK1/2, p65 protein phosphorylation. These effects were alleviated by lidocaine treatment. Furthermore, treatment with rh-EGF reversed the protective effects of lidocaine on inflammatory pain caused by CFA. In conclusion, lidocaine inhibits the inflammatory response and pain through the MAPK/ERK/NF-κB pathway in a rat model of pain induced by CFA.
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Affiliation(s)
- Shuli Zhang
- Department of Pain Medicine, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China
| | - Yan Li
- Department of Gynecology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China
| | - Yingjun Tu
- Department of Orthopaedics, Yili Friendship Hospital, Yining, Xinjiang 835000, P.R. China
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Zang X, Zhao J, Lu C. PM2.5 inducing myocardial fibrosis mediated by Ang II/ERK1/2/TGF-β 1 signaling pathway in mice model. J Renin Angiotensin Aldosterone Syst 2021; 22:14703203211003786. [PMID: 33726569 PMCID: PMC7983242 DOI: 10.1177/14703203211003786] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 02/26/2021] [Indexed: 11/17/2022] Open
Abstract
OBJECTS To discuss the influence of PM2.5 on myocardial fibrosis and related mechanism. METHODS PM2.5 particles were prepared into different concentrations of solution to drip into the mice's trachea twice each week. The mice were divided into five groups, Blank control group (C group), NS control group (J group), high dose group (G group, 10 mg/kg), medium dose group (Z group, 5 mg/kg), and 1ow dose group (D group, 2.5 mg/kg). After 6 weeks, the myocardial fibrosis was observed by HE and Masson staining. The expression of Ang II, ERK1/2, and TGF-β1 was examined by Western Blotting (WB) and Real time PCR (RT-PCR). RESULTS The higher dose PM2.5 was administrated, the worse the myocardial fibrosis was in PM2.5 groups. The expression of Ang II, ERK1/2, and TGF-β1 was increased in higher dose groups in protein and mRNA level. CONCLUSION 1. PM2.5 induced the cardiac fibrosis. 2. PM2.5 dripped into trachea in mice model activated the expression of Ang II, ERK1/2, and TGF-β1. The activation of renin-angiotensin system (RAS) was suggested to participate in the cardiac fibrosis induced by PM2.5.
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Affiliation(s)
- Xiwen Zang
- Tianjin Medical University, Teda
International Cardiovascular Hospital, Tianjin, China
| | - Jun Zhao
- Tianjin Key Laboratory of Ionic-Molecular
Function of Cardiovascular disease(Key Lab-TIC), Tianjin Institute of Cardiology (TIC),
Department of Cardiology, Second Hospital of Tianjin Medical University, Tianjin,
China
| | - Chengzhi Lu
- First Center Clinic College of Tianjin
Medical University, Tianjin First Center Hospital, Tianjin, China
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6
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Zhang P, Ma H, Lin X, Qiu F. Simultaneous quantification and rat pharmacokinetics of formononetin‐7‐
O
‐β‐
d
‐glucoside and its metabolite formononetin by high‐performance liquid chromatography–tandem mass spectrometry. J Sep Sci 2020; 43:2996-3005. [PMID: 32431050 DOI: 10.1002/jssc.202000291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/03/2020] [Accepted: 05/15/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Peng Zhang
- Department of PharmacyXuanwu Hospital of Capital Medical University Beijing P. R. China
| | - Han Ma
- Beijing Key Lab of TCM Collateral Disease Theory ResearchSchool of Traditional Chinese MedicineCapital Medical University Beijing P. R. China
| | - Xiaolan Lin
- Department of PharmacyXuanwu Hospital of Capital Medical University Beijing P. R. China
| | - Feng Qiu
- Beijing Key Lab of TCM Collateral Disease Theory ResearchSchool of Traditional Chinese MedicineCapital Medical University Beijing P. R. China
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Zanese M, Tomaselli G, Roullot-Lacarrière V, Moreau M, Bellocchio L, Grel A, Marsicano G, Sans N, Vallée M, Revest JM. Alpha technology: A powerful tool to detect mouse brain intracellular signaling events. J Neurosci Methods 2020; 332:108543. [PMID: 31830543 DOI: 10.1016/j.jneumeth.2019.108543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 11/15/2019] [Accepted: 12/05/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Phosphorylation by protein kinases is a fundamental molecular process involved in the regulation of signaling activities in living organisms. Understanding this complex network of phosphorylation, especially phosphoproteins, is a necessary step for grasping the basis of cellular pathophysiology. Studying brain intracellular signaling is a particularly complex task due to the heterogeneous complex nature of the brain tissue, which consists of many embedded structures. NEW METHOD Overcoming this degree of complexity requires a technology with a high throughput and economical in the amount of biological material used, so that a large number of signaling pathways may be analyzed in a large number of samples. We have turned to Alpha (Amplified Luminescent Proximity Homogeneous Assay) technology. COMPARISON WITH EXISTING METHOD Western blot is certainly the most commonly used method to measure the phosphorylation state of proteins. Even though Western blot is an accurate and reliable method for analyzing modifications of proteins, it is a time-consuming and large amounts of samples are required. Those two parameters are critical when the goal of the research is to comprehend multi-signaling proteic events so as to analyze several targets from small brain areas. RESULT Here we demonstrate that Alpha technology is particularly suitable for studying brain signaling pathways by allowing rapid, sensitive, reproducible and semi-quantitative detection of phosphoproteins from individual mouse brain tissue homogenates and from cell fractionation and synaptosomal preparations of mouse hippocampus. CONCLUSION Alpha technology represents a major experimental step forward in unraveling the brain phosphoprotein-related molecular mechanisms involved in brain-related disorders.
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Affiliation(s)
- Marion Zanese
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Giovanni Tomaselli
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Valérie Roullot-Lacarrière
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Maïté Moreau
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Luigi Bellocchio
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Agnès Grel
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Giovanni Marsicano
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Nathalie Sans
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Monique Vallée
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France
| | - Jean-Michel Revest
- INSERM U1215, NeuroCentre Magendie, 33077 Bordeaux, France; University of Bordeaux, 33077 Bordeaux, France.
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8
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Somensi N, Rabelo TK, Guimarães AG, Quintans-Junior LJ, de Souza Araújo AA, Moreira JCF, Gelain DP. Carvacrol suppresses LPS-induced pro-inflammatory activation in RAW 264.7 macrophages through ERK1/2 and NF-kB pathway. Int Immunopharmacol 2019; 75:105743. [PMID: 31357087 DOI: 10.1016/j.intimp.2019.105743] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 07/05/2019] [Accepted: 07/05/2019] [Indexed: 01/10/2023]
Abstract
Macrophages are immune system cells that respond to various pathogenic insults. The recognition of antigens is performed through receptors such as TLR4 and RAGE, which recognize pathogen-associated patterns (PAMPs), including lipopolysaccharide (LPS) from Gram-negative bacteria. Carvacrol (CAR) is a phenolic compound found in some essential oils commonly used in folk medicine for treatment of inflammation-related diseases. Previous works observed strong antioxidant actions and some anti-inflammatory effects by CAR in in vivo and in vitro assays. However, the potential pharmacological application of CAR remains limited as details on its mechanisms of action are still missing. Here we investigated the molecular pathways by which CAR acts on LPS-mediated pro-inflammatory activation of RAW 264.7 macrophages. CAR 100 μM protected cells against loss of cell viability induced by LPS (1 μg/mL). Pre-incubation with CAR prevented LPS-induced ERK1/2 phosphorylation, but it had no effect on p38 and JNK activation. The effect of LPS on NF-kB (p65) translocation from cytoplasm to nucleus was inhibited by CAR, as well as NF-kB transcriptional activation. Moreover, LPS-elicited release of TNF-α and IL-1β were inhibited by CAR, as well as activation of phagocytic activity. Such effects may be related to the antioxidant effect of CAR, as the LPS-induced increase in reactive species (RS) production (assessed by DCFH oxidation) and nitric oxide (NO) production (assessed by nitrite quantification) were inhibited by CAR. Altogether, these results demonstrate that CAR exerts relevant anti-inflammatory actions through a cellular mechanism involving ERK1/2 and NF-kB inhibition and possibly related to the antioxidant properties of this phenolic compound.
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Affiliation(s)
- Nauana Somensi
- Centro de Estudos em Estresse Oxidativo, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Thallita Kelly Rabelo
- Centro de Estudos em Estresse Oxidativo, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Laboratório de Neurociências e Ensaios Farmacológicos - LANEF, Departamento de Fisiologia, Universidade Federal de Sergipe, São Cristovão, SE, Brazil
| | | | - Lucindo José Quintans-Junior
- Laboratório de Neurociências e Ensaios Farmacológicos - LANEF, Departamento de Fisiologia, Universidade Federal de Sergipe, São Cristovão, SE, Brazil
| | - Adriano Antunes de Souza Araújo
- Laboratório de Ensaios Farmacêuticos e Toxicidade, Faculdade de Farmácia, Universidade Federal de Sergipe (LeFT/UFS), Brazil
| | - José Cláudio Fonseca Moreira
- Centro de Estudos em Estresse Oxidativo, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Daniel Pens Gelain
- Centro de Estudos em Estresse Oxidativo, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Dong L, Yin L, Zhang Y, Fu X, Lu J. Anti-inflammatory effects of ononin on lipopolysaccharide-stimulated RAW 264.7 cells. Mol Immunol 2017; 83:46-51. [DOI: 10.1016/j.molimm.2017.01.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 12/20/2016] [Accepted: 01/07/2017] [Indexed: 12/16/2022]
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10
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Wang X, Tang SA, Wang R, Qiu Y, Jin M, Kong D. Inhibitory Effects of JEUD-38, a New Sesquiterpene Lactone from Inula japonica Thunb, on LPS-Induced iNOS Expression in RAW264.7 Cells. Inflammation 2016; 38:941-8. [PMID: 25399322 DOI: 10.1007/s10753-014-0056-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We isolated JEUD-38, a new sesquiterpene lactone from Inula japonica Thunb. JEUD-38 dramatically attenuated lipopolysaccharide (LPS)-induced nitric oxide (NO) production. Consistent with this finding, the protein expression of inducible nitric oxide synthase (iNOS) was blocked by JEUD-38 in a concentration-dependent manner. To elucidate the mechanism, we examined the effect of JEUD-38 on LPS-stimulated nuclear factor-κB (NF-κB) nuclear translocation, inhibitory factor-κB (IκB) phosphorylation, and degradation. JEUD-38 reduced the translocation of p65, via abrogating IκB-α phosphorylation and degradation. In addition, JEUD-38 inhibited LPS-stimulated phosphorylation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38. Since iNOS as well as the upstream NF-κB and MAPKs are known to be closely involved in inflammation, these results suggest that JEUD-38 is a promising candidate for prevention and therapy of inflammatory diseases.
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Affiliation(s)
- Xiaoqing Wang
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, 300070, China
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Jeoung M, Jang ER, Liu J, Wang C, Rouchka EC, Li X, Galperin E. Shoc2-tranduced ERK1/2 motility signals--Novel insights from functional genomics. Cell Signal 2016; 28:448-459. [PMID: 26876614 DOI: 10.1016/j.cellsig.2016.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 02/05/2016] [Accepted: 02/08/2016] [Indexed: 12/19/2022]
Abstract
The extracellular signal-regulated kinase 1 and 2 (ERK1/2) pathway plays a central role in defining various cellular fates. Scaffold proteins modulating ERK1/2 activity control growth factor signals transduced by the pathway. Here, we analyzed signals transduced by Shoc2, a critical positive modulator of ERK1/2 activity. We found that loss of Shoc2 results in impaired cell motility and delays cell attachment. As ERKs control cellular fates by stimulating transcriptional response, we hypothesized that the mechanisms underlying changes in cell adhesion could be revealed by assessing the changes in transcription of Shoc2-depleted cells. Using quantitative RNA-seq analysis, we identified 853 differentially expressed transcripts. Characterization of the differentially expressed genes showed that Shoc2 regulates the pathway at several levels, including expression of genes controlling cell motility, adhesion, crosstalk with the transforming growth factor beta (TGFβ) pathway, and expression of transcription factors. To understand the mechanisms underlying delayed attachment of cells depleted of Shoc2, changes in expression of the protein of extracellular matrix (lectin galactoside-binding soluble 3-binding protein; LGALS3BP) were functionally analyzed. We demonstrated that delayed adhesion of the Shoc2-depleted cells is a result of attenuated expression and secretion of LGALS3BP. Together our results suggest that Shoc2 regulates cell motility by modulating ERK1/2 signals to cell adhesion.
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Affiliation(s)
- Myoungkun Jeoung
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, United States
| | - Eun Ryoung Jang
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, United States
| | - Jinpeng Liu
- Markey Cancer Center and Department of Biostatistics, University of Kentucky, Lexington, KY 40536, United States
| | - Chi Wang
- Markey Cancer Center and Department of Biostatistics, University of Kentucky, Lexington, KY 40536, United States
| | - Eric C Rouchka
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY 40292, United States
| | - Xiaohong Li
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY 40292, United States; Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, KY 40292, United States
| | - Emilia Galperin
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, United States.
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Jang ER, Jang H, Shi P, Popa G, Jeoung M, Galperin E. Spatial control of Shoc2-scaffold-mediated ERK1/2 signaling requires remodeling activity of the ATPase PSMC5. J Cell Sci 2015; 128:4428-41. [PMID: 26519477 DOI: 10.1242/jcs.177543] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/21/2015] [Indexed: 12/13/2022] Open
Abstract
The scaffold protein Shoc2 accelerates activity of the ERK1 and ERK2 (ERK1/2, also known as MAPK3 and MAPK1) pathway. Mutations in Shoc2 result in Noonan-like RASopathy, a developmental disorder with a wide spectrum of symptoms. The amplitude of the ERK1/2 signals transduced through the complex is fine-tuned by the HUWE1-mediated ubiquitylation of Shoc2 and its signaling partner RAF-1. Here, we provide a mechanistic basis of how ubiquitylation of Shoc2 and RAF-1 is controlled. We demonstrate that the newly identified binding partner of Shoc2, the (AAA+) ATPase PSMC5, triggers translocation of Shoc2 to endosomes. At the endosomes, PSMC5 displaces the E3 ligase HUWE1 from the scaffolding complex to attenuate ubiquitylation of Shoc2 and RAF-1. We show that a RASopathy mutation that changes the subcellular distribution of Shoc2 leads to alterations in Shoc2 ubiquitylation due to the loss of accessibility to PSMC5. In summary, our results demonstrate that PSMC5 is a new and important player involved in regulating ERK1/2 signal transmission through the remodeling of Shoc2 scaffold complex in a spatially-defined manner.
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Affiliation(s)
- Eun Ryoung Jang
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - HyeIn Jang
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Ping Shi
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Gabriel Popa
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Myoungkun Jeoung
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Emilia Galperin
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
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Aalizadeh R, Pourbasheer E, Ganjali MR. Analysis of B-Raf $$^{\mathrm{V600E}}$$ V 600 E inhibitors using 2D and 3D-QSAR, molecular docking and pharmacophore studies. Mol Divers 2015; 19:915-30. [DOI: 10.1007/s11030-015-9626-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 07/27/2015] [Indexed: 12/14/2022]
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14
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Guo CC, Deng Y, Ye H, Zhu YZ, Zheng XB. Role of MAPK signaling pathways in inflammatory bowel disease. Shijie Huaren Xiaohua Zazhi 2015; 23:229-235. [DOI: 10.11569/wcjd.v23.i2.229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mitogen-activated protein kinases (MAPKs) are a group of highly conserved serine protein kinases which are distributed in the cytoplasm. MAPK signal transduction pathways play a major role in inflammatory reactions and have a close relation with inflammatory bowel disease (IBD). They could be involved in the regulation of inflammatory mediators as well as IBD-associated genes. This paper reviews the role of MAPK signaling pathways in the pathogenesis of IBD, aiming at providing a new method for the treatment of IBD.
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HUWE1 is a molecular link controlling RAF-1 activity supported by the Shoc2 scaffold. Mol Cell Biol 2014; 34:3579-93. [PMID: 25022756 DOI: 10.1128/mcb.00811-14] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Scaffold proteins play a critical role in controlling the activity of the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway. Shoc2 is a leucine-rich repeat scaffold protein that acts as a positive modulator of ERK1/2 signaling. However, the precise mechanism by which Shoc2 modulates the activity of the ERK1/2 pathway is unclear. Here we report the identification of the E3 ubiquitin ligase HUWE1 as a binding partner and regulator of Shoc2 function. HUWE1 mediates ubiquitination and, consequently, the levels of Shoc2. Additionally, we show that both Shoc2 and HUWE1 are necessary to control the levels and ubiquitination of the Shoc2 signaling partner, RAF-1. Depletion of HUWE1 abolishes RAF-1 ubiquitination, with corresponding changes in ERK1/2 pathway activity occurring. Our results indicate that the HUWE1-mediated ubiquitination of Shoc2 is the switch that regulates the transition from an active to an inactive state of the RAF-1 kinase. Taken together, our results demonstrate that HUWE1 is a novel player involved in regulating ERK1/2 signal transmission through the Shoc2 scaffold complex.
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KIM MINJEONG, LEE HYEHYEON, JEONG JINWOO, SEO MINJEONG, KANG BYOUNGWON, PARK JEONGUCK, KIM KYOUNGSOOK, CHO YOUNGSU, SEO KWONIL, KIM GIYOUNG, KIM JUNGIN, CHOI YUNGHYUN, JEONG YONGKEE. Anti-inflammatory effects of 5-hydroxy-3,6,7,8,3′,4′-hexamethoxyflavone via NF-κB inactivation in lipopolysaccharide-stimulated RAW 264.7 macrophage. Mol Med Rep 2014; 9:1197-203. [DOI: 10.3892/mmr.2014.1922] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 11/14/2013] [Indexed: 11/06/2022] Open
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Jeoung M, Abdelmoti L, Jang ER, Vander Kooi CW, Galperin E. Functional Integration of the Conserved Domains of Shoc2 Scaffold. PLoS One 2013; 8:e66067. [PMID: 23805200 PMCID: PMC3689688 DOI: 10.1371/journal.pone.0066067] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 05/05/2013] [Indexed: 01/25/2023] Open
Abstract
Shoc2 is a positive regulator of signaling to extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). Shoc2 is also proposed to interact with RAS and Raf-1 in order to accelerate ERK1/2 activity. To understand the mechanisms by which Shoc2 regulates ERK1/2 activation by the epidermal growth factor receptor (EGFR), we dissected the role of Shoc2 structural domains in binding to its signaling partners and its role in regulating ERK1/2 activity. Shoc2 is comprised of two main domains: the 21 leucine rich repeats (LRRs) core and the N-terminal non-LRR domain. We demonstrated that the N-terminal domain mediates Shoc2 binding to both M-Ras and Raf-1, while the C-terminal part of Shoc2 contains a late endosomal targeting motif. We found that M-Ras binding to Shoc2 is independent of its GTPase activity. While overexpression of Shoc2 did not change kinetics of ERK1/2 activity, both the N-terminal and the LRR-core domain were able to rescue ERK1/2 activity in cells depleted of Shoc2, suggesting that these Shoc2 domains are involved in modulating ERK1/2 activity.
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Affiliation(s)
- Myoungkun Jeoung
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Lina Abdelmoti
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Eun Ryoung Jang
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Craig W. Vander Kooi
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Emilia Galperin
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
- * E-mail:
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Chen W, Sang JY, Liu DJ, Qin J, Huo YM, Xu J, Wu ZY. Desensitization of G-protein-coupled receptors induces vascular hypocontractility in response to norepinephrine in the mesenteric arteries of cirrhotic patients and rats. Hepatobiliary Pancreat Dis Int 2013; 12:295-304. [PMID: 23742775 DOI: 10.1016/s1499-3872(13)60047-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The increased beta-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric arteries of cirrhotic patients and rats. The present study is to investigate the machinery changes of alpha-adrenergic receptors and G proteins and their roles in the contractility of mesenteric arteries of cirrhotic patients and animal models. METHODS Patients with cirrhosis due to hepatitis B and cirrhotic rats induced by CCl4 were studied. Mesenteric artery contractility in response to norepinephrine was determined by a vessel perfusion system. The contractile effect of G protein-coupled receptor kinase-2 (GRK-2) inhibitor on the mesenteric artery was evaluated. The protein expression of the alpha1 adrenergic receptor, G proteins, beta-arrestin-2, GRK-2 as well as the activity of Rho associated coiled-coil forming protein kinase-1 (ROCK-1) were measured by Western blot. In addition, the interaction of alpha1 adrenergic receptor with beta-arrestin-2 was assessed by co-immunoprecipitation. RESULTS The portal vein pressure of cirrhotic patients and rats was significantly higher than that of controls. The dose-response curve to norepinephrine in mesenteric arteriole was shifted to the right, and EC50 was significantly increased in cirrhotic patients and rats. There were no significant differences in the expressions of the alpha1 adrenergic receptor and G proteins in the cirrhotic group compared with the controls. However, the protein expressions of GRK-2 and beta-arrestin-2 were significantly elevated in cirrhotic patients and rats compared with those of the controls. The interaction of the alpha1 adrenergic receptor and beta-arrestin-2 was significantly aggravated. This interaction was significantly reversed by GRK-2 inhibitor. Both the protein expression and activity of ROCK-1 were significantly decreased in the mesenteric artery in patients with cirrhosis compared with those of the controls, and this phenomenon was not shown in the cirrhotic rats. Norepinephrine significantly increased the activity of ROCK-1 in normal rats but not in cirrhotic ones. Norepinephrine significantly increased ROCK-1 activity in cirrhotic rats when GRK-2 inhibitor was used. CONCLUSIONS beta-arrestin-2 expression and its interaction with GPCRs are significantly upregulated in the mesenteric arteries in patients and rats with cirrhosis. These upregulations result in GPCR desensitization, G-protein dysfunction and ROCK inhibition. These may explain the decreased contractility of the mesenteric artery in response to vasoconstrictors.
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Affiliation(s)
- Wei Chen
- Department of Surgery, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200127, China.
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19
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Ríos-Barrera LD, Riesgo-Escovar JR. Regulating cell morphogenesis: The drosophila jun N-terminal kinase pathway. Genesis 2012; 51:147-62. [DOI: 10.1002/dvg.22354] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Revised: 10/14/2012] [Accepted: 10/19/2012] [Indexed: 12/15/2022]
Affiliation(s)
- Luis Daniel Ríos-Barrera
- Developmental Neurobioloy and Neurophysiology Department; Instituto de Neurobiología; Universidad Nacional Autónoma de México; Boulevard Juriquilla #3001; Querétaro, Querétaro; México; c.p. 76230
| | - Juan Rafael Riesgo-Escovar
- Developmental Neurobioloy and Neurophysiology Department; Instituto de Neurobiología; Universidad Nacional Autónoma de México; Boulevard Juriquilla #3001; Querétaro, Querétaro; México; c.p. 76230
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20
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Yoon WJ, Heo SJ, Han SC, Lee HJ, Kang GJ, Kang HK, Hyun JW, Koh YS, Yoo ES. Anti-inflammatory effect of sargachromanol G isolated from Sargassum siliquastrum in RAW 264.7 cells. Arch Pharm Res 2012; 35:1421-30. [PMID: 22941485 DOI: 10.1007/s12272-012-0812-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Revised: 05/02/2012] [Accepted: 05/30/2012] [Indexed: 10/27/2022]
Abstract
A study on the anti-inflammatory activity of brown alga Sargassum siliquastrum led to the isolation of sargachromanol G (SG). In this study, the anti-inflammatory effect and the action mechanism of SG have been investigated in murine macrophage cell line RAW 264.7. SG dosedependently inhibited the production of inflammatory markers [nitric oxide (NO), inducible nitric oxide synthase (iNOS), prostaglandin E(2) (PGE(2)), and cyclooxygenase-2 (COX-2)] and pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6] induced by LPS treatment. To further elucidate the mechanism of this inhibitory effect of SG, we studied LPS-induced nuclear factor-κB (NF-κB) activation and mitogen-activated protein kinases (MAPKs) phosphorylation. SG inhibited the phosphorylation IκB-α and NF-κB (p65 and p50) and MAPK (ERK1/2, JNK, and p38) in a dose dependent manner. These results suggest that the anti-inflammatory activity of SG results from its modulation of pro-inflammatory cytokines and mediators via the suppression of NF-κB activation and MAPK phosphorylation.
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Affiliation(s)
- Weon-Jong Yoon
- School of Medicine, Institute of Medical Science, Jeju National University, Jeju, 690-756, Korea
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Galperin E, Abdelmoti L, Sorkin A. Shoc2 is targeted to late endosomes and required for Erk1/2 activation in EGF-stimulated cells. PLoS One 2012; 7:e36469. [PMID: 22606262 PMCID: PMC3351432 DOI: 10.1371/journal.pone.0036469] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 04/05/2012] [Indexed: 12/21/2022] Open
Abstract
Shoc2 is the putative scaffold protein that interacts with RAS and RAF, and positively regulates signaling to extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). To elucidate the mechanism by which Shoc2 regulates ERK1/2 activation by the epidermal growth factor (EGF) receptor (EGFR), we studied subcellular localization of Shoc2. Upon EGFR activation, endogenous Shoc2 and red fluorescent protein tagged Shoc2 were translocated from the cytosol to a subset of late endosomes containing Rab7. The endosomal recruitment of Shoc2 was blocked by overexpression of a GDP-bound H-RAS (N17S) mutant and RNAi knockdown of clathrin, suggesting the requirement of RAS activity and clathrin-dependent endocytosis. RNAi depletion of Shoc2 strongly inhibited activation of ERK1/2 by low, physiological EGF concentrations, which was rescued by expression of wild-type recombinant Shoc2. In contrast, the Shoc2 (S2G) mutant, that is myristoylated and found in patients with the Noonan-like syndrome, did not rescue ERK1/2 activation in Shoc2-depleted cells. Shoc2 (S2G) was not located in late endosomes but was present on the plasma membrane and early endosomes. These data suggest that targeting of Shoc2 to late endosomes may facilitate EGFR-induced ERK activation under physiological conditions of cell stimulation by EGF, and therefore, may be involved in the spatiotemporal regulation of signaling through the RAS-RAF module.
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Affiliation(s)
- Emilia Galperin
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, Kentucky, United States of America.
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Aroor AR, Jackson DE, Shukla SD. Dysregulated phosphorylation and nuclear translocation of cyclic AMP response element binding protein (CREB) in rat liver after chronic ethanol binge. Eur J Pharmacol 2012; 679:101-8. [PMID: 22269225 DOI: 10.1016/j.ejphar.2011.12.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 12/21/2011] [Accepted: 12/28/2011] [Indexed: 01/26/2023]
Abstract
Binge ethanol during chronic ethanol abuse augments liver injury but the underlying mechanism remains unknown. CREB (cyclic AMP response element binding protein) is implicated as a key transcription factor in liver regeneration and hepatic glucose and lipid metabolism. We examined the effects of ethanol on the phosphorylation of CREB in hepatocytes, and in vivo in rat liver after chronic ethanol binge. For in vivo studies, rats were fed ethanol in liquid diet for 4 weeks followed by single binge administration of ethanol (intragastric, 5 g/kg body weight). Four hours after binge administration, liver samples were collected and analyzed. Treatment of hepatocytes with ethanol caused increased phosphorylation of p38 MAPK (mitogen activated protein kinase), MSK-1 (mitogen and stress activated kinase) and CREB in the nuclear compartment without activation of ERK1/2 (extracellular regulated kinase); whereas angiotensin II induced activation of CREB was accompanied by activation of ERK1/2. In chronic ethanol-binge studies, analysis of the whole cell extracts showed increased phosphorylation of CREB, with no effect on CREB protein levels; increased phospho-ERK1/2, and decreased phospho-p38 MAPK. In contrast, the nuclear levels of phospho-CREB and CREB protein were reduced. Reduction in phospho-CREB and CREB proteins in the nuclear extracts was accompanied by suppression of mRNA levels for CPT-1 (carnitine palmitoyl transferase-1) and increase in hepatic steatosis after binge. It is concluded that binge ethanol causes defect in the nuclear accumulation of CREB protein, phospho-CREB, and an exaggerated hepatic steatosis. These in vivo effects are distinct from the effects of ethanol on hepatocytes in vitro.
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Affiliation(s)
- Annayya R Aroor
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO 65212, United States
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Moon JY, Yang EJ, Kim SS, Kang JY, Kim GO, Lee NH, Hyun CG. Sasa quelpaertensis phenylpropanoid derivative suppresses lipopolysaccharide-induced nitric oxide synthase and cyclo-oxygenase-2 expressions in RAW 264.7 cells. YAKUGAKU ZASSHI 2012; 131:961-7. [PMID: 21628985 DOI: 10.1248/yakushi.131.961] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
3-O-p-Coumaroyl-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-O-β-D-gulcopyranosylpropanol (ESQ10) is a naturally occurring phenylpropanoid derivative isolated from Sasa quelpaertensis (Gramineae). In the present study, we discovered that ESQ10 inhibits nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. ESQ10 attenuated LPS-induced synthesis of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in parallel and inhibited LPS-induced interleukin-6 production, as determined by an enzyme-linked immunosorbent assay in the macrophages. The mechanism of the antiinflammatory action of ESQ10, i.e., suppression of nuclear factor (NF)-κB and mitogen-activated protein kinase activation, has been documented. However, ESQ10 could not influence LPS-mediated IκB-α degradation and extracellular signal-regulated kinase/c-Jun amino-terminal kinase phosphorylation at concentrations of up to 373 µM. To test the potential application of ESQ10 as a topical material, we also conducted a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on human HaCaT keratinocytes as well as human dermal fibroblast cells. In this assay, ESQ10 did not induce cytotoxicity. Taken together, the results suggest that ESQ10 may be considered an antiinflammatory candidate for treating inflammatory and skin diseases.
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Affiliation(s)
- Ji-Young Moon
- Bio-Convergence Center, Jeju Technopark, Jeju, Korea
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James TT, Aroor AR, Lim RW, Shukla SD. Histone H3 phosphorylation (Ser10, Ser28) and phosphoacetylation (K9S10) are differentially associated with gene expression in liver of rats treated in vivo with acute ethanol. J Pharmacol Exp Ther 2011; 340:237-47. [PMID: 22025646 DOI: 10.1124/jpet.111.186775] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The epigenetic histone modification by ethanol is emerging as one of the mechanisms for its deleterious effects in the liver. In this context, we have investigated the role of histone H3 phosphorylation at Ser10 (P-H3-Ser10), and Ser28 (P-H3-Ser28) in liver after acute ethanol treatment in vivo. Ethanol was administered intraperitoneally in male Sprague-Dawley rats. Ethanol dose-response (1-5 g/kg body weight) and time-course (1-4 h) experiments were conducted, and various parameters were monitored. Steatosis and necrosis (serum alanine aminotransferase) of the liver increased in 4 h, suggesting liver injury. There were differences between P-H3-Ser10 and P-H3-Ser28 at 1 h, with the latter being more sensitive to lower ethanol doses. It was noteworthy that phosphorylation of both serines disappeared at the highest dose used (5 g/kg). We also examined phosphoacetylation of histone H3 at K9S10 and observed a dramatic increase. The changes in histone H3 phosphorylation and phosphoacetylation were also accompanied with expression of early response genes (c-fos, c-jun, mitogen-activated protein kinase phosphatase-1). Chromatin immunoprecipitation assays in samples from 1.5 and 4 h of ethanol administration indicated that increased histone H3 phosphorylation at Ser28 was associated with the promoters of c-jun and plasminogen activator inhibitor-1. In conclusion, this study demonstrates for the first time that in vivo exposure of liver to acute ethanol induced phosphorylation and phosphoacetylation of histone H3, and these modifications are differentially involved in the mRNA expression of genes.
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Affiliation(s)
- Taryn T James
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO 65203, USA
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Drew BA, Burow ME, Beckman BS. MEK5/ERK5 pathway: the first fifteen years. Biochim Biophys Acta Rev Cancer 2011; 1825:37-48. [PMID: 22020294 DOI: 10.1016/j.bbcan.2011.10.002] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 10/07/2011] [Indexed: 12/22/2022]
Abstract
While conventional MAP kinase pathways are one of the most highly studied signal transduction molecules, less is known about the MEK5 signaling pathway. This pathway has been shown to play a role in normal cell growth cycles, survival and differentiation. The MEK5 pathway is also believed to mediate the effects of a number of oncogenes. MEK5 is the upstream activator of ERK5 in many epithelial cells. Activation of the MEK-MAPK pathway is a frequent event in malignant tumor formation and contributes to chemoresistance and anti-apoptotic signaling. This pathway may be involved in a number of more aggressive, metastatic varieties of cancer due to its role in cell survival, proliferation and EMT transitioning. Further study of this pathway may lead to new prognostic factors and new drug targets to combat more aggressive forms of cancer.
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Affiliation(s)
- Barbara A Drew
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA 70112, USA
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Wu RWK, Yow CMN, Wong CK, Lam YH. Photodynamic therapy (PDT) - Initiation of apoptosis via activation of stress-activated p38 MAPK and JNK signal pathway in H460 cell lines. Photodiagnosis Photodyn Ther 2011; 8:254-63. [PMID: 21864799 DOI: 10.1016/j.pdpdt.2010.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 12/02/2010] [Accepted: 12/07/2010] [Indexed: 11/19/2022]
Abstract
AIMS The purpose of this study was to investigate the photoefficacies of protoporphyrin IX (PpIX) generated by drug precursor 5-aminolevulinic acid (ALA) and its hexyl ester (H-ALA) on two human non-small lung carcinoma cell lines (H460/Bcl-2 and H460/neo). MAIN METHODS Drug uptake and the photoefficacies of PpIX were measured by flow cytometry and MTT assay; while the mode of cell death and alternation of signal transduction pathways were studied with 4',6-diamidino-2-phenylindole (DAPI) staining and Western blot analysis, respectively. KEY FINDINGS The flow cytometric analysis of H-ALA (5μM) uptake revealed optimal fluorescent intensity at 8h incubation, while ALA (0.5mM) was still far from saturation. The LD(30) of H-ALA-PDT was 30μM, 2J/cm(2), while the LD(30) of ALA-PDT was 3mM, 2J/cm(2). The dark toxicities mediated by both pro-drug H-ALA and ALA were negligible. By DAPI staining, apoptotic cell death was observed. In addition, by Western blot analysis, H-ALA- and ALA-mediated PDT initiated apoptotic cell death via the up-regulation and activation of p38 mitogen activated protein kinase (MAPK), the stress-activated c-jun N-terminal kinases (JNK) and ERK. SIGNIFICANCE These results suggested that H-ALA and ALA mediated PDT displayed similar photocytotoxicities towards the two non-small lung cancer cells. Our present study also demonstrates H-ALA or ALA mediated PDT in H460 cells are closely related to the activation of p38 MAPK and JNK signalling pathway.
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Affiliation(s)
- R W K Wu
- Department of Health Technology & Informatics, The Hong Kong Polytechnic University, Hong Kong
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Zhang ZH, Yu Y, Wei SG, Felder RB. Centrally administered lipopolysaccharide elicits sympathetic excitation via NAD(P)H oxidase-dependent mitogen-activated protein kinase signaling. J Hypertens 2010; 28:806-16. [PMID: 20027123 DOI: 10.1097/hjh.0b013e3283358b6e] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The mechanisms by which inflammation activates sympathetic drive in heart failure and hypertension remain ill-defined. In this study, an intracerebroventricular injection of lipopolysaccharide (LPS) was used to induce the expression of cytokines and other inflammatory mediators in the brain, in the absence of other excitatory mediators, and the downstream signaling pathways leading to sympathetic activation were examined using intracerebroventricular injections of blocking or inhibiting agents. METHODS AND RESULTS In anesthetized rats, intracerebroventricular injection of LPS (5 microg) increased (P < 0.05) renal sympathetic nerve activity, blood pressure and heart rate. LPS increased (P < 0.05) hypothalamic mRNA for NAD(P)H oxidase subunits p47 and gp91, NAD(P)H oxidase-dependent superoxide generation, hypothalamic mRNA for tumor necrosis factor-alpha, cyclooxygenase-2 and cerebrospinal fluid levels of tumor necrosis factor-alpha and prostaglandin E2. In the paraventricular nucleus of hypothalamus, dihydroethidium staining for superoxide expression and c-Fos activity (indicating neuronal excitation) increased. The superoxide scavenger tempol significantly (P < 0.05) diminished the expression of inflammatory mediators, as well as superoxide expression and neuronal excitation in paraventricular nucleus. SB203580 (p38 mitogen-activated protein kinase inhibitor) also reduced the expression of inflammatory mediators in hypothalamus and cerebrospinal fluid. Tempol, apocynin [NAD(P)H oxidase inhibitor], SB203580 and NS398 (cyclooxygenase-2 inhibitor) all reduced cerebrospinal fluid prostaglandin E2 and the sympathoexcitatory response to LPS. LPS also increased angiotensin II type 1 receptor mRNA, a response blocked by apocynin and tempol but not by SB203580. CONCLUSION These findings suggest that central inflammation in pathophysiological conditions activates the sympathetic nervous system via NAD(P)H oxidase and p38 mitogen-activated protein kinase-dependent synthesis of prostaglandin E2.
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Affiliation(s)
- Zhi-Hua Zhang
- Medical Service, Department of Veterans Affairs Medical Center, Roy J and Lucille A Carver College of Medicine, University of Iowa, Iowa City, Iowa52242, USA
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Yoon WJ, Moon JY, Kang JY, Kim GO, Lee NH, Hyun CG. Neolitsea Sericea Essential Oil Attenuates LPS-induced Inflammation in RAW 264.7 Macrophages by Suppressing NF-κB and MAPK Activation. Nat Prod Commun 2010. [DOI: 10.1177/1934578x1000500835] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The chemical composition and antiinflammatory activities of hydrodistilled essential oil from Neolitsea sericea leaves (NSE) have been investigated for the first time. The chemical constituents of NSE were analysed by GC-MS and found to include sericenine (32.3%), sabinene (21.0%), trans-β-ocimene (13.3%), β-caryophyllene (4.8%), and 4-terpineol (4.2%). The effects of NSE on nitric oxide (NO), prostaglandin E2 (PGE2), tumour necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages were also examined. Pro-inflammatory cytokine and mediator tests indicated that NSE has excellent dose-dependent inhibitory activities. To further examine the mechanism responsible for the inhibition of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression by NSE, we examined the effect of NSE on nuclear factor-κB (NF-κB) activation and the phosphorylation of mitogen-activated protein kinases (MAPK). NSE inhibited NF-κB activation by LPS, and this was associated with the abrogation of IκB-α phosphorylation and subsequent decreases in nuclear p50 and p65 protein levels. Further, the phosphorylation of p38, ERK and JNK was suppressed by NSE in a concentration-dependent manner. These results suggest that NSE exerts antiinflammatory effects in LPS-stimulated RAW 264.7 macrophages by inhibition of NF-κB activation and MAPK phosphorylation, and, therefore, may be useful for treatment of inflammatory diseases.
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Affiliation(s)
- Weon-Jong Yoon
- Jeju High-Tech Development Institute (HiDI), Jeju 699-943, Korea
| | - Ji-Young Moon
- Jeju High-Tech Development Institute (HiDI), Jeju 699-943, Korea
| | - Ji-Yong Kang
- Jeju High-Tech Development Institute (HiDI), Jeju 699-943, Korea
| | - Gi-Ok Kim
- Jeju High-Tech Development Institute (HiDI), Jeju 699-943, Korea
| | - Nam Ho Lee
- Department of Chemistry, Cheju National University, Jeju 690-756, Korea
| | - Chang-Gu Hyun
- Jeju High-Tech Development Institute (HiDI), Jeju 699-943, Korea
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Aroor AR, James TT, Jackson DE, Shukla SD. Differential changes in MAP kinases, histone modifications, and liver injury in rats acutely treated with ethanol. Alcohol Clin Exp Res 2010; 34:1543-51. [PMID: 20586759 DOI: 10.1111/j.1530-0277.2010.01239.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Acute ethanol is known to affect cells and organs but the underlying molecular mechanisms are poorly explored. Recent developments highlight the potential importance of mitogen-activated protein kinases, MAPKs (i.e., ERK1/2, p38, and JNK1/2) signaling, and histone modifications (i.e., acetylation, methylation, and phosphorylation) in the actions of ethanol in hepatocytes. We have therefore investigated significance of these molecular steps in vivo using a model in which rats were acutely administered ethanol intraperitoneally (IP). METHODS Ethanol was administered IP (3.5 gm/kg body weight) to 12-week-old male Sprague-Dawley rats. Liver was subsequently removed at 1 and 4 hours. Serum was used for alcohol and ALT assays. At the time of the removal of liver, small portions of each liver were formalin-fixed and stained with hematoxylin and eosin (H&E) and used for light microscopy. Western blot analysis was carried out with specific primary antibodies for various parameters. RESULTS There were clear differences at 1 and 4 hours in blood ethanol, ALT, steatosis, and cleaved caspase 3. Apoptosis at 1 hour was followed by necrosis at 4 hours. Acute alcohol elicited a marked increase in the phosphorylation of ERK1/2 and moderate increases in the phosphorylation of p38 MAPK and JNK. Temporally different phosphorylation of histone H3 at ser-10 and ser-28 occurred and acetylation of histone H3 at lys 9 increased progressively. CONCLUSIONS There were distinct differences in the behavior of the activation of the 3 MAP kinases and histone modifications after acute short exposure of liver to ethanol in vivo. Although all 3 MAPKs were rapidly activated at 1 hour, the necrosis, occurring at 4 hours, correlated to sustained activation of ERK1/2. Transient activation of p38 is associated with rapid phosphorylation of histone H3, whereas prolonged activation of ERK1/2 is correlated to persistent histone H3 acetylation.
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Affiliation(s)
- Annayya R Aroor
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri, USA
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Yoon WJ, Moon JY, Song G, Lee YK, Han MS, Lee JS, Ihm BS, Lee WJ, Lee NH, Hyun CG. Artemisia fukudo essential oil attenuates LPS-induced inflammation by suppressing NF-kappaB and MAPK activation in RAW 264.7 macrophages. Food Chem Toxicol 2010; 48:1222-9. [PMID: 20156520 DOI: 10.1016/j.fct.2010.02.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 02/06/2010] [Accepted: 02/08/2010] [Indexed: 01/21/2023]
Abstract
In the present study, the chemical constituents of Artemisia fukudo essential oil (AFE) were investigated using GC-MS. The major constituents were alpha-thujone (48.28%), beta-thujone (12.69%), camphor (6.95%) and caryophyllene (6.01%). We also examined the effects of AFE on the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6, in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Western blotting and RT-PCR tests indicated that AFE has potent dose-dependent inhibitory effects on pro-inflammatory cytokines and mediators. We investigated the mechanism by which AFE inhibits NO and PGE(2) by examining the level of nuclear factor-kappaB (NF-kappaB) activation within the mitogen-activated protein kinase (MAPK) pathway, which is an inflammation-induced signal pathway in RAW 264.7 cells. AFE inhibited LPS-induced ERK, JNK, and p38 phosphorylation. Furthermore, AFE inhibited the LPS-induced phosphorylation and degradation of Ikappa-B-alpha, which is required for the nuclear translocations of the p50 and p65 NF-kappaB subunits in RAW 264.7 cells. Our results suggest that AFE might exert an anti-inflammatory effect by inhibiting the expression of pro-inflammatory cytokines. Such an effect is mediated by a blocking of NF-kappaB activation which consequently inhibits the generation of inflammatory mediators in RAW264.7 cells. AFE may be useful for treating inflammatory diseases.
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Affiliation(s)
- W J Yoon
- Jeju Biodiversity Research Institute, Jeju High-Tech Development Institute, Jeju, Republic of Korea
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Effects of glutamine on the nuclear factor-kappaB signaling pathway of murine peritoneal macrophages. Amino Acids 2010; 39:435-41. [DOI: 10.1007/s00726-009-0459-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Accepted: 12/20/2009] [Indexed: 12/15/2022]
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THE SELECTIVE ADENOSINE A2A RECEPTOR AGONIST CGS 21680 REDUCES JNK MAPK ACTIVATION IN OLIGODENDROCYTES IN INJURED SPINAL CORD. Shock 2009; 32:578-85. [DOI: 10.1097/shk.0b013e3181a20792] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Hennenberg M, Trebicka J, Kohistani AZ, Heller J, Sauerbruch T. Vascular hyporesponsiveness to angiotensin II in rats with CCl(4)-induced liver cirrhosis. Eur J Clin Invest 2009; 39:906-13. [PMID: 19522833 DOI: 10.1111/j.1365-2362.2009.02181.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Portal hypertension is triggered by vasodilation due to impaired contraction of extrahepatic vessels. Angiotensin II type 1 (AT(1)) receptor-induced vasocontraction is mediated by G proteins and may be desensitized by recruitment of beta-arrestin-2 to the receptor. In this study, we analysed the interaction of AT(1) receptors with beta-arrestin-2 in the context of vascular hypocontractility in rats with CCl(4)-induced cirrhosis. METHODS Micronodular liver cirrhosis in rats (n = 15) was induced by regular CCl(4) exposure. Age-matched rats (n = 15) served as controls. Contractility of aortic rings was measured by myography. Protein expressions and phosphorylations were assessed by Western blot analysis, and AT(1) receptor interaction with beta-arrestin-2 by co-immunoprecipitation. RESULTS Aortic rings from CCl(4) rats were hypocontractile to angiotensin II independent of nitric oxide synthases (Nomega-nitro-l-arginine methyl ester 200 microM). Expression of the AT(1) receptor, Galpha(q/11) and the contraction-mediating effector Rho kinase was similar in aortas from both groups. Expression and AT(1) receptor binding of beta-arrestin-2 were up-regulated in aortas from CCl(4) rats. Stimulation of isolated aortas with exogenous angiotensin II caused recruitment of beta-arrestin-2 in aortas from noncirrhotic rats, but no further interaction of AT(1) receptors with beta-arrestin-2 was found in aortas from CCl(4) rats. While angiotensin II stimulation resulted in Rho kinase activation in aortas from noncirrhotic rats but not in aortas from CCl(4) rats, extracellular signal-regulated kinase activation in response to angiotensin II was observed in aortas from both groups. CONCLUSIONS Vascular hyporesponsiveness to angiotensin II in CCl(4) rats is due to enhanced interaction of the AT(1) receptor with beta-arrestin-2 and consecutively changed receptor function.
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Affiliation(s)
- M Hennenberg
- Department of Internal Medicine I, University of Bonn, Bonn, Germany.
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Broom OJ, Widjaya B, Troelsen J, Olsen J, Nielsen OH. Mitogen activated protein kinases: a role in inflammatory bowel disease? Clin Exp Immunol 2009; 158:272-80. [PMID: 19793335 DOI: 10.1111/j.1365-2249.2009.04033.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Since their discovery more than 15 years ago, the mitogen activated protein kinases (MAPK) have been implicated in an ever-increasingly diverse array of pathways, including inflammatory signalling cascades. Inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease, are characterized by the perpetual production of inflammatory mediators. Research into the transduction pathway behind this over-production has highlighted the potential mediating role for the MAPKs and their related signalling components. This review highlights some of the research into the role for the MAPKs and their related signalling proteins in influencing the progression of IBD.
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Affiliation(s)
- O J Broom
- Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
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MacKinnon K, Burton J, Zajac A, Notter D. Microarray analysis reveals difference in gene expression profiles of hair and wool sheep infected with Haemonchus contortus. Vet Immunol Immunopathol 2009; 130:210-20. [DOI: 10.1016/j.vetimm.2009.02.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 01/30/2009] [Accepted: 02/16/2009] [Indexed: 10/21/2022]
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Abstract
Scaffold proteins contribute to the spatiotemporal control of MAPK signaling and KSR1 is an ERK cascade scaffold that localizes to the plasma membrane in response to growth factor treatment. To better understand the molecular mechanisms of KSR1 function, we examined the interaction of KSR1 with each of the ERK cascade components, Raf, MEK, and ERK. Here, we identify a hydrophobic motif within the proline-rich sequence (PRS) of MEK1 and MEK2 that is required for constitutive binding to KSR1 and find that MEK binding and residues in the KSR1 CA1 region enable KSR1 to form a ternary complex with B-Raf and MEK following growth factor treatment that enhances MEK activation. We also find that docking of active ERK to the KSR1 scaffold allows ERK to phosphorylate KSR1 and B-Raf on feedback S/TP sites. Strikingly, feedback phosphorylation of KSR1 and B-Raf promote their dissociation and result in the release of KSR1 from the plasma membrane. Together, these findings provide unique insight into the signaling dynamics of the KSR1 scaffold and reveal that through regulated interactions with Raf and ERK, KSR1 acts to both potentiate and attenuate ERK cascade activation, thus regulating the intensity and duration of ERK cascade signaling emanating from the plasma membrane during growth factor signaling.
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