Oxidative stress-dependent contribution of HMGB1 to the interplay between apoptosis and autophagy in diabetic rat liver.

Science.gov (United States)

Petrović, Anja; Bogojević, Desanka; Korać, Aleksandra; Golić, Igor; Jovanović-Stojanov, Sofija; Martinović, Vesna; Ivanović-Matić, Svetlana; Stevanović, Jelena; Poznanović, Goran; Grigorov, Ilijana

2017-11-01

The progression of oxidative stress, resulting cell damage, and cell death underlies the etiology of liver damage/dysfunction as a complication of diabetes. High-mobility group box 1 (HMGB1) protein, a chromatin-binding nuclear protein and damage-associated molecular pattern molecule, is integral to oxidative stress and signaling pathways regulating cell death and cell survival. We previously found that in streptozotocin (STZ)-induced diabetic rats, reduction of oxidative stress after melatonin administration lowered necrotic cell death and increased expression of HMGB1 and hepatocellular damage. In the present study, we examined whether alleviation of diabetes-attendant oxidative stress and ensuing change in HMGB1 expression influence the dynamic equilibrium between apoptosis/autophagy and liver damage. We observed that elevated HMGB1 protein levels in diabetic rat liver accompanied increased interactions of HMGB1 with TLR4 and RAGE, and activation of the intrinsic apoptotic pathway and Beclin 1-dependent autophagy. The absence of p62 degradation in diabetic rat liver pointed to defective autophagy which was responsible for lower autophagosome/autophagolysosome formation and an increased apoptosis/autophagy ratio. Compared to diabetic rats, in melatonin-treated diabetic rats, the structure of liver cells was preserved, HMGB1/TLR4 interaction and downstream apoptotic signaling were significantly reduced, HMGB1/Beclin 1 colocalization and interactions were augmented and Beclin 1-mediated autophagy, mithophagy in particular, were increased. We concluded that in mild oxidative stress, HMGB1 is cytoprotective, whereas in intense oxidative stress, HMGB1 actions promote cell death and liver damage. Since reduced HMGB1 binds to RAGE but not to TLR4, redox modification of HMGB1 as a mechanism regulating the cross-talk between apoptosis and autophagy in diabetes is discussed.

The role of high mobility group box 1 (HMGB-1) in the diabetic retinopathy inflammation and apoptosis.

Science.gov (United States)

Yu, Yao; Yang, Lu; Lv, Jinlei; Huang, Xu; Yi, Jinglin; Pei, Chonggang; Shao, Yi

2015-01-01

Diabetic Retinopathy (DR) is one of the most common complications of the late phase diabetes, and also a common cause of blindness. High mobility group box 1 (HMGB-1) is considered to be an inflammatory mediator in the late phase that promotes inflammation and neovascularization in diabetes. Therefore, this paper discussed the role of HMGB-1 in diabetic retinopathy inflammation and neovascularization. 96 adult SD rats were randomly divided into control and diabetes group. The diabetic rat model was established by intraperitoneal injection of streptomycin (0.1 mol/L). Western blot was applied to determine HMGB-1 and its receptor RAGE and TLR2 protein expression in the serum. TUNEL was used to detect retinal apoptosis. Immunofluorescence was performed to test HMGB1 protein expression in retina. HBGM-1 and RAGE expression in diabetic rat retina was significantly higher than the control (P detection showed that diabetic rat retinal cells presented obviously higher apoptosis rate (P diabetic rat retinal cells (P diabetic retinopathy by binding with RAGE receptor to accelerate rat retinal cells apoptosis.

High ASMA+ Fibroblasts and Low Cytoplasmic HMGB1+ Breast Cancer Cells Predict Poor Prognosis.

Science.gov (United States)

Amornsupak, Kamolporn; Jamjuntra, Pranisa; Warnnissorn, Malee; O-Charoenrat, Pornchai; Sa-Nguanraksa, Doonyapat; Thuwajit, Peti; Eccles, Suzanne A; Thuwajit, Chanitra

2017-10-01

The influence of cancer-associated fibroblasts (CAFs) and high mobility group box 1 (HMGB1) has been recognized in several cancers, although their roles in breast cancer are unclear. The present study aimed to determine the levels and prognostic significance of α-smooth muscle actin-positive (ASMA + ) CAFs, plus HMGB1 and receptor for advanced glycation end products (RAGE) in cancer cells. A total of 127 breast samples, including 96 malignant and 31 benign, were examined for ASMA, HMGB1, and RAGE by immunohistochemistry. The χ 2 test and Fisher's exact test were used to test the association of each protein with clinicopathologic parameters. The Kaplan-Meier method or log-rank test and Cox regression were used for survival analysis. ASMA + fibroblast infiltration was significantly increased in the tumor stroma compared with that in benign breast tissue. The levels of cytoplasmic HMGB1 and RAGE were significantly greater in the breast cancer tissue than in the benign breast tissues. High ASMA expression correlated significantly with large tumor size, clinical stage III-IV, and angiolymphatic and perinodal invasion. In contrast, increased cytoplasmic HMGB1 correlated significantly with small tumor size, pT stage, early clinical stage, luminal subtype (but not triple-negative subtype), and estrogen receptor and progesterone receptor expression. The levels of ASMA (hazard ratio, 14.162; P = .010) and tumor cytoplasmic HMGB1 (hazard ratio, 0.221; P = .005) could serve as independent prognostic markers for metastatic relapse in breast cancer patients. The ASMA-high/HMGB1-low profile provided the most reliable prediction of metastatic relapse. We present for the first time, to the best of our knowledge, the potential clinical implications of the combined assessment of ASMA + fibroblasts and cytoplasmic HMGB1 in breast cancer. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

HMGB1 Contributes to the Expression of P-Glycoprotein in Mouse Epileptic Brain through Toll-Like Receptor 4 and Receptor for Advanced Glycation End Products.

Directory of Open Access Journals (Sweden)

Yan Chen

Full Text Available The objective of the present study was to investigate the role of high-mobility group box-1 (HMGB1 in the seizure-induced P-glycoprotein (P-gp overexpression and the underlying mechanism. Kainic acid (KA-induced mouse seizure model was used for in vivo experiments. Male C57BL/6 mice were divided into four groups: normal saline control (NS group, KA-induced epileptic seizure (EP group, and EP group pretreated with HMGB1 (EP+HMGB1 group or BoxA (HMGB1 antagonist, EP+BoxA group. Compared to the NS group, increased levels of HMGB1 and P-gp in the brain were observed in the EP group. Injection of HMGB1 before the induction of KA further increased the expression of P-gp while pre-treatment with BoxA abolished this up-regulation. Next, the regulatory role of HMGB1 and its potential involved signal pathways were investigated in mouse microvascular endothelial bEnd.3 cells in vitro. Cells were treated with HMGB1, HMGB1 plus lipopolysaccharide from Rhodobacter sphaeroides (LPS-RS [toll-like receptor 4 (TLR4 antagonist], HMGB1 plus FPS-ZM1 [receptor for advanced glycation end products (RAGE inhibitor], HMGB1 plus SN50 [nuclear factor-kappa B (NF-κB inhibitor], or vehicle. Treatment with HMGB1 increased the expression levels of P-gp, TLR4, RAGE and the activation of NF-κB in bEnd.3 cells. These effects were inhibited by the pre-treatment with either LPS-RS or FPS-ZM1, and were abolished by the pre-treatment of SN50 or a combination treatment of both LPS-RS and FPS-ZM1. Luciferase reporter assays showed that exogenous expression of NF-κB p65 increased the promoter activity of multidrug resistance 1a (P-gp-encoding gene in endothelial cells. These data indicate that HMGB1 contributes to the overexpression of P-gp in mouse epileptic brain tissues via activation of TLR4/RAGE receptors and the downstream transcription factor NF-κB in brain microvascular endothelial cells.

AGEs, RAGEs and s-RAGE; friend or foe for cancer.

Science.gov (United States)

Ahmad, Saheem; Khan, Hamda; Siddiqui, Zeba; Khan, Mohd Yasir; Rehman, Shahnawaz; Shahab, Uzma; Godovikova, Tatyana; Silnikov, Vladimir; Moinuddin

2018-04-01

Impaired awareness of glycation biology in cancer initiation and progression is one of the fundamental reasons for its meticulous investigation of the molecules involved in signalling pathway. Glycation of biological macromolecules results in the progression of advanced glycation end-products (AGEs) that proliferates the process of carcinogenesis by activation of transcription factors and release of cytokines. The receptor for advanced glycation end-products (RAGEs) with the binding of its different ligands like; AGEs, HMGB1 and S100 activate the signalling arrays. The activation of downstream signalling pathway ultimately leads to the pathophysiological conditions of diabetes, ageing, neurological disorders and cancers as well as a result of the activation of transcription factors which is discussed in the main body text of this review. However, there might be a likelihood of the positive effect of the HMGB1 and S100 proteins in cancer. Still, some untouched mechanisms might be responsible for the establishment of the function of AGE-RAGE or AGE-sRAGE axis activation that leads to the friend-foe association with the cancers. The levels of RAGE and s-RAGE may be a useful biomarker of ligand-RAGE pathway activation and cancer. Thus, the possibility of providing a potential complement to carcinogenesis is very high which might be an interesting target for therapeutic interventions. This article is an insightful assessment on AGE, RAGE and s-RAGE for its possible role in cancer onset and progression. The novel therapeutic targets for cancer prevention or inhibition are also explained in brief in relation to AGE and RAGE. Copyright © 2017 Elsevier Ltd. All rights reserved.

Local and systemic RAGE axis changes in pulmonary hypertension: CTEPH and iPAH.

Directory of Open Access Journals (Sweden)

Bernhard Moser

Full Text Available OBJECTIVE: The molecular determinants of chronic thromboembolic pulmonary hypertension (CTEPH and idiopathic pulmonary arterial hypertension (iPAH remain poorly understood. The receptor for advanced glycation endproducts (RAGE and its ligands: HMGB1 and S100A9 are involved in inflammatory disorders. We sought to investigate the role of the RAGE axis in patients with CTEPH undergoing pulmonary endarterectomy (PEA, iPAH undergoing lung transplantation (LuTX. The high pulmonary vascular resistance in CTEPH/iPAH results in pressure overload of the right ventricle. We compared sRAGE measurements to that of patients with aortic valve stenosis (AVS - pressure overload of the left ventricle. METHODS: We enrolled patients with CTEPH(26, iPAH(15, AVS(15 and volunteers(33. Immunohistochemistry with antibodies to RAGE and HMGB1 was performed on PEA specimens and lung tissues. We employed enzyme-linked immunosorbent assays to determine the concentrations of sRAGE, esRAGE, HMGB1 and S100A9 in serum of volunteers and patients with CTEPH, iPAH, AVS before and after PEA, LuTX and aortic valve replacement (AVR. RESULTS: In endarterectomised tissues from patients with CTEPH RAGE and HMGB1 were identified in myofibroblasts (α-SMA+vimentin+CD34-, recanalizing vessel-like structures of distal myofibrotic tissues and endothelium of neointima. RAGE was differentially expressed in prototypical Heath Edwards lesions in iPAH. We found significantly increased serum concentrations of sRAGE, esRAGE and HMGB1 in CTEPH. In iPAH, sRAGE and esRAGE were significantly higher than in controls. Serum concentrations of sRAGE were significantly elevated in iPAH(p<0.001 and CTEPH(p = 0.001 compared to AVS. Serum sRAGE was significantly higher in iPAH compared to CTEPH(p = 0.042 and significantly reduced in AVS compared to controls(p = 0.001. There were no significant differences in sRAGE serum concentrations before and after surgical therapy for CTEPH, iPAH or AVS. CONCLUSIONS: Our

Down-regulation of LncRNA TUG1 enhances radiosensitivity in bladder cancer via suppressing HMGB1 expression

OpenAIRE

Jiang, Huijuan; Hu, Xigang; Zhang, Hongzhi; Li, Wenbo

2017-01-01

Background Long non-coding RNAs (lncRNAs) have been reported to regulate the sensitivity of different cancer cells to chemoradiotherapy. Aberrant expression of lncRNA Taurine-upregulated gene 1 (TUG1) has been found to be involved in the development of bladder cancer, however, its function and underlying mechanism in the radioresistance of bladder cancer remains unclear. Methods Quantitative real-time PCR (qRT-PCR) was conducted to measure the expression of TUG1 and HMGB1 mRNA in bladder canc...

High-Mobility Group Box 1 Mediates Fibroblast Activity via RAGE-MAPK and NF-κB Signaling in Keloid Scar Formation.

Science.gov (United States)

Kim, Jihee; Park, Jong-Chul; Lee, Mi Hee; Yang, Chae Eun; Lee, Ju Hee; Lee, Won Jai

2017-12-28

Emerging studies have revealed the involvement of high-mobility group box 1 (HMGB1) in systemic fibrotic diseases, yet its role in the cutaneous scarring process has not yet been investigated. We hypothesized that HMGB1 may promote fibroblast activity to cause abnormal cutaneous scarring. In vitro wound healing assay with normal and keloid fibroblasts demonstrated that HMGB1 administration promoted the migration of both fibroblasts with increased speed and a greater traveling distance. Treatment of the HMGB1 inhibitor glycyrrhizic acid (GA) showed an opposing effect on both activities. To analyze the downstream mechanism, the protein levels of extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (AKT), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were measured by western blot analysis. HMGB1 increased the expression levels of ERK1/2, AKT, and NF-κB compared to the control, which was suppressed by GA. HMGB1 promoted both normal and keloid fibroblasts migration to a degree equivalent to that achieved with TGF-β. We concluded that HMGB1 activates fibroblasts via the receptor for advanced glycation end product (RAGE)-mitogen-activated protein kinases (MAPK) and NF-κB interaction signaling pathways. Further knowledge of the relationship of HMGB1 with skin fibrosis may lead to a promising clinical approach to manage abnormal scarring.

Kaempferol alleviates LPS-induced neuroinflammation and BBB dysfunction in mice via inhibiting HMGB1 release and down-regulating TLR4/MyD88 pathway.

Science.gov (United States)

Cheng, Xiao; Yang, Ying-Lin; Yang, Huan; Wang, Yue-Hua; Du, Guan-Hua

2018-03-01

Kaempferol is a natural flavonoid with many biological activities including anti-oxidation and anti-inflammation. Nevertheless, its anti-neuroinflammation role and the relevant mechanism remain unclear. The present study was to investigate effects of kaempferol against LPS-induced neuroinflammation and blood-brain barrier dysfunction as well as the mechanism in mice. BALB/c mice were treated with LPS 5mg/kg to induce inflammation after pre-treatment with kaempferol 25, 50, or 100mg/kg for 7days. The results showed that kaempferol reduced the production of various pro-inflammatory factors and inflammatory proteins including IL-1β, IL-6, TNF-α, MCP-1, COX-2 and iNOS in brain tissues. In addition, kaempferol also protected BBB integrity and increased BBB related proteins including occludin-1, claudin-1 and CX43 in brain of LPS-induced mice. Furthermore, kaempferol significantly reduced HMGB1 level and suppressed TLR4/MyD88 inflammatory pathway in both transcription level and translation level. These results collectively suggested that kaempferol might be a promising neuroprotective agent for alleviating inflammatory responses and BBB dysfunction by inhibiting HMGB1 release and down-regulating TLR4/MyD88 inflammatory pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

Nuclear DAMP complex-mediated RAGE-dependent macrophage cell death

Energy Technology Data Exchange (ETDEWEB)

Chen, Ruochan [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Fu, Sha; Fan, Xue-Gong [Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Lotze, Michael T.; Zeh, Herbert J. [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Tang, Daolin, E-mail: tangd2@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Kang, Rui, E-mail: kangr@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States)

2015-03-13

High mobility group box 1 (HMGB1), histone, and DNA are essential nuclear components involved in the regulation of chromosome structure and function. In addition to their nuclear function, these molecules act as damage-associated molecular patterns (DAMPs) alone or together when released extracellularly. The synergistic effect of these nuclear DNA-HMGB1-histone complexes as DAMP complexes (nDCs) on immune cells remains largely unexplored. Here, we demonstrate that nDCs limit survival of macrophages (e.g., RAW264.7 and peritoneal macrophages) but not cancer cells (e.g., HCT116, HepG2 and Hepa1-6). nDCs promote production of inflammatory tumor necrosis factor α (TNFα) release, triggering reactive oxygen species-dependent apoptosis and necrosis. Moreover, the receptor for advanced glycation end products (RAGE), but not toll-like receptor (TLR)-4 and TLR-2, was required for Akt-dependent TNFα release and subsequent cell death following treatment with nDCs. Genetic depletion of RAGE by RNAi, antioxidant N-Acetyl-L-cysteine, and TNFα neutralizing antibody significantly attenuated nDC-induced cell death. These findings provide evidence supporting novel signaling mechanisms linking nDCs and inflammation in macrophage cell death. - Highlights: • Nuclear DAMP complexes (nDCs) selectively induce cell death in macrophages, but not cancer cells. • TNFα-mediated oxidative stress is required for nDC-induced death. • RAGE-mediated Akt activation is required for nDC-induced TNFα release. • Blocking RAGE and TNFα inhibits nDC-induced macrophage cell death.

Persistent Increase in Microglial RAGE Contributes to Chronic Stress-Induced Priming of Depressive-like Behavior.

Science.gov (United States)

Franklin, Tina C; Wohleb, Eric S; Zhang, Yi; Fogaça, Manoela; Hare, Brendan; Duman, Ronald S

2018-01-01

Chronic stress-induced inflammatory responses occur in part via danger-associated molecular pattern (DAMP) molecules, such as high mobility group box 1 protein (HMGB1), but the receptor(s) underlying DAMP signaling have not been identified. Microglia morphology and DAMP signaling in enriched rat hippocampal microglia were examined during the development and expression of chronic unpredictable stress (CUS)-induced behavioral deficits, including long-term, persistent changes after CUS. The results show that CUS promotes significant morphological changes and causes robust upregulation of HMGB1 messenger RNA in enriched hippocampal microglia, an effect that persists for up to 6 weeks after CUS exposure. This coincides with robust and persistent upregulation of receptor for advanced glycation end products (RAGE) messenger RNA, but not toll-like receptor 4 in hippocampal microglia. CUS also increased surface expression of RAGE protein on hippocampal microglia as determined by flow cytometry and returned to basal levels 5 weeks after CUS. Importantly, exposure to short-term stress was sufficient to increase RAGE surface expression as well as anhedonic behavior, reflecting a primed state that results from a persistent increase in RAGE messenger RNA expression. Further evidence for DAMP signaling in behavioral responses is provided by evidence that HMGB1 infusion into the hippocampus was sufficient to cause anhedonic behavior and by evidence that RAGE knockout mice were resilient to stress-induced anhedonia. Together, the results provide evidence of persistent microglial HMGB1-RAGE expression that increases vulnerability to depressive-like behaviors long after chronic stress exposure. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Receptor for advanced glycation end products - membrane type1 matrix metalloproteinase axis regulates tissue factor expression via RhoA and Rac1 activation in high-mobility group box-1 stimulated endothelial cells.

Directory of Open Access Journals (Sweden)

Koichi Sugimoto

Full Text Available BACKGROUND: Atherosclerosis is understood to be a blood vessel inflammation. High-mobility group box-1 (HMGB-1 plays a key role in the systemic inflammation. Tissue factor (TF is known to lead to inflammation which promotes thrombus formation. Membrane type1 matrix metalloprotease (MT1-MMP associates with advanced glycation endproducts (AGE triggered-TF protein expression and phosphorylation of NF-κB. However, it is still unclear about the correlation of MT1-MMP and HMBG-1-mediated TF expression. In this study, we investigated the molecular mechanisms of TF expression in response to HMGB-1 stimulation and the involvement of MT1-MMP in endothelial cells. METHODS AND RESULTS: Pull-down assays and Western blotting revealed that HMGB-1 induced RhoA/Rac1 activation and NF-kB phosphorylation in cultured human aortic endothelial cells. HMGB-1 increased the activity of MT1-MMP, and inhibition of RAGE or MT1-MMP by siRNA suppressed HMGB-1-induced TF upregulation as well as HMGB-1-triggered RhoA/Rac1 activation and NF-kB phosphorylation. CONCLUSIONS: The present study showed that RAGE/MT1-MMP axis modified HMBG-1-mediated TF expression through RhoA and Rac1 activation and NF-κB phosphorylation in endothelial cells. These results suggested that MT1-MMP was involved in vascular inflammation and might be a good target for treating atherosclerosis.

The role of high mobility group box 1(HMGB1)in the pathogenesis of kidney diseases

Institute of Scientific and Technical Information of China (English)

Qingjie Chen; Xiaofeng Guan; Xiaocong Zuo; Jianglin Wang; Wenjun Yin

2016-01-01

High mobility group box 1(HMGB1) is a nuclear protein that can bind to DNA and act as a co-factor for gene transcription. When released into extracellular fluid, it plays a proinflammatory role by acting as a damage-associated molecular pattern molecule(DAMP)(also known as an alarmin) to initiate innate immune responses by activating multiple cell surface receptors such as the receptor for advanced glycation end-products(RAGE) and toll-like receptors(TLRs), TLR2, TLR4 or TLR9. This proinflammatory role is now considered to be important in the pathogenesis of a wide range of kidney diseases whether they result from hemodynamic changes, renal tubular epithelial cell apoptosis, kidney tissue fibrosis or inflammation. This review summarizes our current understanding of the role of HMGB1 in kidney diseases and how the HMGB1-mediated signaling pathway may constitute a new strategy for the treatment of kidney diseases.

Structure function relationship of recombinant sRAGE

OpenAIRE

Premaratne, Dinamithra Gedara Sujeewani Rasika

2017-01-01

The receptor for advanced glycation end-products (RAGE) is a member of the immunoglobulin super family of cell surface receptors. It acts as the direct mediator of physiological and pathological responses such as inflammation, chemotaxis, neurite outgrowth, angiogenesis, apoptosis and proliferation. RAGE is known to bind with structurally and functionally diverse ligands, such as advanced glycation end-products (AGEs), high mobility group family proteins including HMGB-1/amphoterin, matrix pr...

Resveratrol treatment reveals a novel role for HMGB1 in regulation of the type 1 interferon response in dengue virus infection.

Science.gov (United States)

Zainal, Nurhafiza; Chang, Chih-Peng; Cheng, Yi-Lin; Wu, Yan-Wei; Anderson, Robert; Wan, Shu-Wen; Chen, Chia-Ling; Ho, Tzong-Shiann; AbuBakar, Sazaly; Lin, Yee-Shin

2017-02-20

Dengue is one of the most significant mosquito-borne virus diseases worldwide, particularly in tropical and subtropical regions. This study sought to examine the antiviral activity of resveratrol (RESV), a phytoalexin secreted naturally by plants, against dengue virus (DENV) infection. Our data showed that RESV inhibits the translocation of high mobility group box 1 (HMGB1), a DNA binding protein that normally resides in the nucleus, into the cytoplasm and extracellular milieu. HMGB1 migrates out of the nucleus during DENV infection. This migration is inhibited by RESV treatment and is mediated by induction of Sirt1 which leads to the retention of HMGB1 in the nucleus and consequently helps in the increased production of interferon-stimulated genes (ISGs). Nuclear HMGB1 was found to bind to the promoter region of the ISG and positively regulated the expression of ISG. The enhanced transcription of ISGs by nuclear HMGB1 thus contributes to the antiviral activity of RESV against DENV. To the best of our knowledge, this is the first report to demonstrate that RESV antagonizes DENV replication and that nuclear HMGB1 plays a role in regulating ISG production.

RAGE, receptor of advanced glycation endoproducts, negatively regulates chondrocytes differentiation.

Directory of Open Access Journals (Sweden)

Tatsuya Kosaka

Full Text Available RAGE, receptor for advanced glycation endoproducts (AGE, has been characterized as an activator of osteoclastgenesis. However, whether RAGE directly regulates chondrocyte proliferation and differentiation is unclear. Here, we show that RAGE has an inhibitory role in chondrocyte differentiation. RAGE expression was observed in chondrocytes from the prehypertrophic to hypertrophic regions. In cultured cells, overexpression of RAGE or dominant-negative-RAGE (DN-RAGE demonstrated that RAGE inhibited cartilaginous matrix production, while DN-RAGE promoted production. Additionally, RAGE regulated Ihh and Col10a1 negatively but upregulated PTHrP receptor. Ihh promoter analysis and real-time PCR analysis suggested that downregulation of Cdxs was the key for RAGE-induced inhibition of chondrocyte differentiation. Overexpression of the NF-κB inhibitor I-κB-SR inhibited RAGE-induced NF-κB activation, but did not influence inhibition of cartilaginous matrix production by RAGE. The inhibitory action of RAGE was restored by the Rho family GTPases inhibitor Toxin B. Furthermore, inhibitory action on Ihh, Col10a1 and Cdxs was reproduced by constitutively active forms, L63RhoA, L61Rac, and L61Cdc42, but not by I-κB-SR. Cdx1 induced Ihh and Col10a1 expressions and directly interacted with Ihh promoter. Retinoic acid (RA partially rescued the inhibitory action of RAGE. These data combined suggests that RAGE negatively regulates chondrocyte differentiation at the prehypertrophic stage by modulating NF-κB-independent and Rho family GTPases-dependent mechanisms.

Expression of high mobility group box 1 in inflamed dental pulp and its chemotactic effect on dental pulp cells

International Nuclear Information System (INIS)

Zhang, Xufang; Jiang, Hongwei; Gong, Qimei; Fan, Chen; Huang, Yihua; Ling, Junqi

2014-01-01

Highlights: • HMGB1 translocated from nucleus to cytoplasm during dental pulp inflammation. • HMGB1and its receptor RAGE were up-regulated in hDPCs under LPS stimulation. • HMGB1 enhanced hDPCs migration and induces cytoskeleton reorganization. • HMGB1 may play a critical role in dental pulp repair during inflamed state. - Abstract: High mobility group box 1 protein (HMGB1) is a chromatin protein which can be released extracellularly, eliciting a pro-inflammatory response and promoting tissue repair process. This study aimed to examine the expression and distribution of HMGB1 and its receptor RAGE in inflamed dental pulp tissues, and to assess its effects on proliferation, migration and cytoskeleton of cultured human dental pulp cells (DPCs). Our data demonstrated that cytoplasmic expression of HMGB1 was observed in inflamed pulp tissues, while HMGB1 expression was confined in the nuclei in healthy dental pulp. The mRNA expression of HMGB1 and RAGE were significantly increased in inflamed pulps. In in vitro cultured DPCs, expression of HMGB1 in both protein and mRNA level was up-regulated after treated with lipopolysaccharide (LPS). Exogenous HMGB1 enhanced DPCs migration in a dose-dependent manner and induced the reorganization of f-actin in DPCs. Our results suggests that HMGB1 are not only involved in the process of dental pulp inflammation, but also play an important role in the recruitment of dental pulp stem cells, promoting pulp repair and regeneration

Expression of high mobility group box 1 in inflamed dental pulp and its chemotactic effect on dental pulp cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xufang, E-mail: xufang.zhang@student.qut.edu.au [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4059 (Australia); Jiang, Hongwei, E-mail: jianghw@163.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Gong, Qimei, E-mail: gongqmei@gmail.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Fan, Chen, E-mail: c3.fan@student.qut.edu.au [Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4059 (Australia); Huang, Yihua, E-mail: enu0701@163.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Ling, Junqi, E-mail: lingjq@mail.sysu.edu.cn [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China)

2014-08-08

Highlights: • HMGB1 translocated from nucleus to cytoplasm during dental pulp inflammation. • HMGB1and its receptor RAGE were up-regulated in hDPCs under LPS stimulation. • HMGB1 enhanced hDPCs migration and induces cytoskeleton reorganization. • HMGB1 may play a critical role in dental pulp repair during inflamed state. - Abstract: High mobility group box 1 protein (HMGB1) is a chromatin protein which can be released extracellularly, eliciting a pro-inflammatory response and promoting tissue repair process. This study aimed to examine the expression and distribution of HMGB1 and its receptor RAGE in inflamed dental pulp tissues, and to assess its effects on proliferation, migration and cytoskeleton of cultured human dental pulp cells (DPCs). Our data demonstrated that cytoplasmic expression of HMGB1 was observed in inflamed pulp tissues, while HMGB1 expression was confined in the nuclei in healthy dental pulp. The mRNA expression of HMGB1 and RAGE were significantly increased in inflamed pulps. In in vitro cultured DPCs, expression of HMGB1 in both protein and mRNA level was up-regulated after treated with lipopolysaccharide (LPS). Exogenous HMGB1 enhanced DPCs migration in a dose-dependent manner and induced the reorganization of f-actin in DPCs. Our results suggests that HMGB1 are not only involved in the process of dental pulp inflammation, but also play an important role in the recruitment of dental pulp stem cells, promoting pulp repair and regeneration.

Minocycline attenuates both OGD-induced HMGB1 release and HMGB1-induced cell death in ischemic neuronal injury in PC12 cells

Energy Technology Data Exchange (ETDEWEB)

Kikuchi, Kiyoshi [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Department of Neurosurgery, Omuta City General Hospital, 2-19-1 Takarazaka, Omuta-City, Fukuoka 836-8567 (Japan); Kawahara, Ko-ichi; Biswas, Kamal Krishna; Ito, Takashi [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Tancharoen, Salunya [Department of Pharmacology, Faculty of Dentistry, Mahidol University, 6 Yothe Rd., Rajthevee Bangkok 10400 (Thailand); Morimoto, Yoko [Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Matsuda, Fumiyo [Division of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8560 (Japan); Oyama, Yoko; Takenouchi, Kazunori [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Miura, Naoki [Laboratory of Veterinary Diagnostic Imaging, Department of Veterinary Medicine, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Arimura, Noboru; Nawa, Yuko; Meng, Xiaojie; Shrestha, Binita; Arimura, Shinichiro [Division of Laboratory and Vascular Medicine, Field of Cardiovascular and Respiratory Disorders, Department of Advanced Therapeutics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); and others

2009-07-24

High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.

Minocycline attenuates both OGD-induced HMGB1 release and HMGB1-induced cell death in ischemic neuronal injury in PC12 cells

International Nuclear Information System (INIS)

Kikuchi, Kiyoshi; Kawahara, Ko-ichi; Biswas, Kamal Krishna; Ito, Takashi; Tancharoen, Salunya; Morimoto, Yoko; Matsuda, Fumiyo; Oyama, Yoko; Takenouchi, Kazunori; Miura, Naoki; Arimura, Noboru; Nawa, Yuko; Meng, Xiaojie; Shrestha, Binita; Arimura, Shinichiro

2009-01-01

High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.

CK2 phosphorylation of Schistosoma mansoni HMGB1 protein regulates its cellular traffic and secretion but not its DNA transactions.

Science.gov (United States)

de Abreu da Silva, Isabel Caetano; Carneiro, Vitor Coutinho; Maciel, Renata de Moraes; da Costa, Rodrigo Furtado Madeiro; Furtado, Daniel Rodrigues; de Oliveira, Francisco Meirelles Bastos; da Silva-Neto, Mário Alberto Cardoso; Rumjanek, Franklin David; Fantappié, Marcelo Rosado

2011-01-01

The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space. We showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated. We showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis.

CK2 phosphorylation of Schistosoma mansoni HMGB1 protein regulates its cellular traffic and secretion but not its DNA transactions.

Directory of Open Access Journals (Sweden)

Isabel Caetano de Abreu da Silva

Full Text Available BACKGROUND: The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1, a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1 is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space. PRINCIPAL FINDINGS: We showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated. CONCLUSIONS: We showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis.

Unfractionated Heparin Alleviates Human Lung Endothelial Barrier Dysfunction Induced by High Mobility Group Box 1 Through Regulation of P38–GSK3β–Snail Signaling Pathway

Directory of Open Access Journals (Sweden)

Zhenggang Luan

2018-04-01

Full Text Available Background/Aims: The high mobility group box 1 (HMGB1 has been regarded as an important inflammatory mediator. Previous studies showed the involvement of HMGB1 protein in the dysfunction of endothelial barrier function during acute lung injury. However, the molecular mechanism remains unclear. Methods: In this study, we used recombinant human HMGB1 (rhHMGB1 and HMGB1 plasmid to treat human pulmonary microvascular endothelial cell (HPMECs. We examined endothelial permeability by measuring TEER value and HRP flux. Western blot and real-time PCR were used to examined change of endothelial-to-mesenchymal transition (EndoMT markers and related pathways. Immunofluorescence was used to examine localization and expression of ZO-1 and VE-cadherin. SB203580.was used to block p38 pathway. Unfractionated heparin (UFH and RAGE siRNA were also used to antagonize the effect of HMGB1. Results: We showed that HMGB1 induced EndoMT with downregulation of ZO-1 and VE-cadherin at both mRNA and protein levels in HPMECs. We also demonstrated that HMGB1 upregulated endothelial permeability by measuring TEER value and HRP flux. Moreover, HMGB1 activated p38/GSK3β/Snail signaling pathway and treatment with p38 inhibitor SB203580 abolished its biological effects. In addition, we found that UFH was able to reverse the effect of HMGB1 on EndoMT and endothelial permeability through inhibition of p38 signaling in a dose-dependent manner. We discovered that RAGE, a membrane receptor of HMGB1, transduced p38/Snail pathway to EndoMT. RAGE siRNA inhibited the effect of HMGB1 induced EndoMT in HPMECs. Conclusion: The present study demonstrated that HMGB1 induced EndoMT through RAGE receptor and p38/GSK3β/Snail pathway. While UFH antagonized HMGB1 and maintained the integrity of the endothelial barrier through p38 inhibition.

Overexpression of Receptor for Advanced Glycation End Products and High-Mobility Group Box 1 in Human Dental Pulp Inflammation

Directory of Open Access Journals (Sweden)

Salunya Tancharoen

2014-01-01

Full Text Available High mobility group box 1 (HMGB1, a nonhistone DNA-binding protein, is released into the extracellular space and promotes inflammation. HMGB1 binds to related cell signaling transduction receptors, including receptor for advanced glycation end products (RAGE, which actively participate in vascular and inflammatory diseases. The aim of this study was to examine whether RAGE and HMGB1 are involved in the pathogenesis of pulpitis and investigate the effect of Prevotella intermedia (P. intermedia lipopolysaccharide (LPS on RAGE and HMGB1 expression in odontoblast-like cells (OLC-1. RAGE and HMGB1 expression levels in clinically inflamed dental pulp were higher than those in healthy dental pulp. Upregulated expression of RAGE was observed in odontoblasts, stromal pulp fibroblasts-like cells, and endothelial-like cell lining human pulpitis tissue. Strong cytoplasmic HMGB1 immunoreactivity was noted in odontoblasts, whereas nuclear HMGB1 immunoreactivity was seen in stromal pulp fibroblasts-like cells in human pulpitis tissue. LPS stimulated OLC-1 cells produced HMGB1 in a dose-dependent manner through RAGE. HMGB1 translocation towards the cytoplasm and secretion from OLC-1 in response to LPS was inhibited by TPCA-1, an inhibitor of NF-κB activation. These findings suggest that RAGE and HMGB1 play an important role in the pulpal immune response to oral bacterial infection.

Association of high mobility group BOX-1 and receptor for advanced glycation endproducts with clinicopathological features of haematological malignancies: a systematic review

Directory of Open Access Journals (Sweden)

Austin H. Nguyen

2017-01-01

Full Text Available High-mobility group box 1 (HMGB1 is a versatile protein with nuclear and extracellular functions. In the extracellular milieu, HMGB1 binds to several receptors, notably the receptor for advanced glycation end-products (RAGE. The expressions of HMGB1 and RAGE have been described in a variety of cancers. However, the clinical values of HMGB1 and RAGE in haematological malignancies have yet to be evaluated. A systematic search through PubMed and the Web of Science for articles discussing the role of HMGB1 and RAGE in haematological malignancies produced 15 articles. Overexpression of HMGB1 was reported to be associated with malignancy and, in certain studies, poor prognosis and tumour aggressiveness. Only one included study investigated the clinical value of RAGE, in which no significant difference was found between expression of RAGE in CLL neoplastic cells and nonmalignant controls. The discussed associations of HMGB1 and RAGE with clinicopathological characteristics of patients with haematological malignancies warrants further investigation into the prognostic and diagnostic value of both of these molecules.

Receptor for advanced glycation end products and its ligand high-mobility group box-1 mediate allergic airway sensitization and airway inflammation.

Science.gov (United States)

Ullah, Md Ashik; Loh, Zhixuan; Gan, Wan Jun; Zhang, Vivian; Yang, Huan; Li, Jian Hua; Yamamoto, Yasuhiko; Schmidt, Ann Marie; Armour, Carol L; Hughes, J Margaret; Phipps, Simon; Sukkar, Maria B

2014-08-01

The receptor for advanced glycation end products (RAGE) shares common ligands and signaling pathways with TLR4, a key mediator of house dust mite (Dermatophagoides pteronyssinus) (HDM) sensitization. We hypothesized that RAGE and its ligand high-mobility group box-1 (HMGB1) cooperate with TLR4 to mediate HDM sensitization. To determine the requirement for HMGB1 and RAGE, and their relationship with TLR4, in airway sensitization. TLR4(-/-), RAGE(-/-), and RAGE-TLR4(-/-) mice were intranasally exposed to HDM or cockroach (Blatella germanica) extracts, and features of allergic inflammation were measured during the sensitization or challenge phase. Anti-HMGB1 antibody and the IL-1 receptor antagonist Anakinra were used to inhibit HMGB1 and the IL-1 receptor, respectively. The magnitude of allergic airway inflammation in response to either HDM or cockroach sensitization and/or challenge was significantly reduced in the absence of RAGE but not further diminished in the absence of both RAGE and TLR4. HDM sensitization induced the release of HMGB1 from the airway epithelium in a biphasic manner, which corresponded to the sequential activation of TLR4 then RAGE. Release of HMGB1 in response to cockroach sensitization also was RAGE dependent. Significantly, HMGB1 release occurred downstream of TLR4-induced IL-1α, and upstream of IL-25 and IL-33 production. Adoptive transfer of HDM-pulsed RAGE(+/+)dendritic cells to RAGE(-/-) mice recapitulated the allergic responses after HDM challenge. Immunoneutralization of HMGB1 attenuated HDM-induced allergic airway inflammation. The HMGB1-RAGE axis mediates allergic airway sensitization and airway inflammation. Activation of this axis in response to different allergens acts to amplify the allergic inflammatory response, which exposes it as an attractive target for therapeutic intervention. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

TLR4-HMGB1 signaling pathway affects the inflammatory reaction of autoimmune myositis by regulating MHC-I.

Science.gov (United States)

Wan, Zemin; Zhang, Xiujuan; Peng, Anping; He, Min; Lei, Zhenhua; Wang, Yunxiu

2016-12-01

To analyze the effects of TLR4 on the expression of the HMGB1, MHC-I and downstream cytokines IL-6 and TNF-α, and to investigate the biological role of the TLR4-HMGB1 signaling pathway in the development of the autoimmune myositis. We built mice models with experimental autoimmune myositis (EAM) and used the inverted screen experiment to measure their muscle endurance; we also examined inflammatory infiltration of muscle tissues after HE staining; and we assessed the expression of MHC-I using immunohistochemistry. In addition, peripheral blood mononuclear cells (PBMC) were extracted and flow cytometry was utilized to detect the effect of IFN-γ on the expression of MHC-I. Furthermore, PBMCs were treated with IFN-γ, anti-TLR4, anti-HMGB1 and anti-MHC-I. Real-time PCR and western blotting were employed to examine the expressions of TLR4, HMGB1 and MHC-I in different groups. The ELISA method was also utilized to detect the expression of the downstream cytokines TNF-α and IL-6. The expressions of TLR4, HMGB1 and MHC-I in muscle tissues from mice with EAM were significantly higher than those in the control group (all Pmyositis inflammation by regulating the expression of MHC-I and other pro-inflammatory cytokines. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of glycyrrhizin on traumatic brain injury in rats and its mechanism

Directory of Open Access Journals (Sweden)

Gu Xiangjin

2014-02-01

Full Text Available 【Abstract】Objective: To investigate the neuroprotective effects of glycyrrhizin (Gly as well as its effect on expression of high-mobility group box 1 (HMGB1 in rats after traumatic brain injury (TBI. Methods: Male Sprague-Dawley rats were randomly divided into three groups: sham group, TBI group, and TBI+Gly group (n=36 per group. Rat TBI model was made by using the modified Feeney’s method. In TBI+Gly group, Gly was administered intravenously at a dosage of 10 mg/kg 30 min after TBI. At 24 h after TBI, motor function and brain water content were evaluated. Meanwhile, HMGB1/HMGB1 receptors including toll-like receptor 4 (TLR4 and receptor for advanced glycation end products (RAGE/nuclear factor- κB(NF- κB signaling pathway and inflammatory cytokines in the injured brain tissues were detected using quantitative real-time polymerase chain reaction, western blot, electrophoretic mobility shift assay and enzyme-linked immunosorbent assay. Furthermore, HMGB1, RAGE and TLR4 immunohistochemistry and apoptosis were analyzed. Results: Beam walking performance impairment and brain edema were significantly reduced in TBI+Gly group compared with TBI group; meanwhile, the over-expressions of HMGB1/HMGB1 receptors (TLR4 and RAGE/NF-κB DNA-binding activity and inflammatory cytokines were inhibited. The percentages of HMGB1, RAGE and TLR4- positive cells and apoptotic cells were respectively 58.37%±5.06%, 54.15%±4.65%, 65.50%± 4.83%, 52.02%± 4.63% in TBI group and 39.99%±4.99%, 34.87%±5.02%, 43.33%±4.54%, 37.84%±5.16% in TBI+Gly group (all P<0.01 compared with TBI group. Conclusion: Gly can reduce secondary brain injury and improve outcomes in rat following TBI by down-regulation of HMGB1/HMGB1 receptors (TLR4 and RAGE/NF-κB - mediated inflammatory responses in the injured rat brain.

Omega-3 polyunsaturated fatty acid supplementation attenuates microglial-induced inflammation by inhibiting the HMGB1/TLR4/NF-κB pathway following experimental traumatic brain injury.

Science.gov (United States)

Chen, Xiangrong; Wu, Shukai; Chen, Chunnuan; Xie, Baoyuan; Fang, Zhongning; Hu, Weipeng; Chen, Junyan; Fu, Huangde; He, Hefan

2017-07-24

Microglial activation and the subsequent inflammatory response in the central nervous system play important roles in secondary damage after traumatic brain injury (TBI). High-mobility group box 1 (HMGB1) protein, an important mediator in late inflammatory responses, interacts with transmembrane receptor for advanced glycation end products (RAGE) and toll-like receptors (TLRs) to activate downstream signaling pathways, such as the nuclear factor (NF)-κB signaling pathway, leading to a cascade amplification of inflammatory responses, which are related to neuronal damage after TBI. Omega-3 polyunsaturated fatty acid (ω-3 PUFA) is a commonly used clinical immunonutrient, which has antioxidative and anti-inflammatory effects. However, the effects of ω-3 PUFA on HMGB1 expression and HMGB1-mediated activation of the TLR4/NF-κB signaling pathway are not clear. The Feeney DM TBI model was adopted to induce brain injury in rats. Modified neurological severity scores, brain water content, and Nissl staining were employed to determine the neuroprotective effects of ω-3 PUFA supplementation. Assessment of microglial activation in lesioned sites and protein markers for proinflammatory, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, interferon (IFN)-γ, and HMGB1 were used to evaluate neuroinflammatory responses and anti-inflammation effects of ω-3 PUFA supplementation. Immunofluorescent staining and western blot analysis were used to detect HMGB1 nuclear translocation, secretion, and HMGB1-mediated activation of the TLR4/NF-κB signaling pathway to evaluate the effects of ω-3 PUFA supplementation and gain further insight into the mechanisms underlying the development of the neuroinflammatory response after TBI. It was found that ω-3 PUFA supplementation inhibited TBI-induced microglial activation and expression of inflammatory factors (TNF-α, IL-1β, IL-6, and IFN-γ), reduced brain edema, decreased neuronal apoptosis, and improved neurological

Sirt1 S-nitrosylation induces acetylation of HMGB1 in LPS-activated RAW264.7 cells and endotoxemic mice.

Science.gov (United States)

Kim, Young Min; Park, Eun Jung; Kim, Hye Jung; Chang, Ki Churl

2018-06-18

Excessive inflammation plays a detrimental role in endotoxemia. A recent study indicated that alarmins such as high mobility group box 1 (HMGB1) have drawn attention as therapeutic targets of sepsis. Post-translational modification (i.e., acetylation of lysine residues) of HMGB1 leads to the release of HMGB1 into the cellular space, operating as a warning signal that induces inflammation. Sirtuin 1 (SIRT1) has been shown to negatively regulate HMGB1 hyperacetylation and its extracellular release in sepsis. Therefore, we hypothesized that the S-nitrosylation (SNO) of SIRT1 may disrupt the ability of SIRT1 to negatively regulate the hyperacetylation of HMGB1. As long as the S-nitrosylation of SIRT1 occurs during septic conditions, it may worsen the situation. We found that the activity of SIRT1 decreased as the SNO-SIRT1 levels increased, resulting in HMGB1 release by LPS in RAW264.7 cells. Both the iNOS inhibitor (1400 W) and silencing iNOS significantly inhibited SNO-SIRT1, allowing increases in SIRT1 activity that decreased the HMGB1 release by LPS. SNAP, a NO donor, significantly increased both SNO-SIRT1 levels and the HMGB1 release that was accompanied by decreased sirt1 activity. However, sirtinol, a Sirt1 inhibitor, by itself decreased Sirt1 activity compared to that of the control, so that it did not affect already increased SNO-SIRT levels by SNAP. Most importantly, in lung tissues of LPS-endotoxic mice, significantly increased levels of SNO-SIRT were found, which was inhibited by 1400 W treatment. Plasma nitrite and HMGB1 levels were significantly higher than those in the sham controls, and the elevated levels were significantly lowered in the presence of 1400 W. We concluded that the S-nitrosylation of Sirt1 under endotoxic conditions may uninhibit the acetylation of HMGB1 and its extracellular release. Copyright © 2018 Elsevier Inc. All rights reserved.

RAGE and TGF-β1 Cross-Talk Regulate Extracellular Matrix Turnover and Cytokine Synthesis in AGEs Exposed Fibroblast Cells.

Directory of Open Access Journals (Sweden)

Andreea Iren Serban

Full Text Available AGEs accumulation in the skin affects extracellular matrix (ECM turnover and triggers diabetes associated skin conditions and accelerated skin aging. The receptor of AGEs (RAGE has an essential contribution to cellular dysfunction driven by chronic inflammatory responses while TGF-β1 is critical in both dermal homeostasis and inflammation. We investigated the contribution of RAGE and TGF-β1 to the modulation of inflammatory response and ECM turnover in AGEs milieu, using a normal fibroblast cell line. RAGE, TGF-β1, collagen I and III gene and protein expression were upregulated after exposure to AGEs-BSA, and MMP-2 was activated. AGEs-RAGE was pivotal in NF-κB dependent collagen I expression and joined with TGF-β1 to stimulate collagen III expression, probably via ERK1/2 signaling. AGEs-RAGE axis induced upregulation of TGF-β1, TNF-α and IL-8 cytokines. TNF-α and IL-8 were subjected to TGF-β1 negative regulation. RAGE's proinflammatory signaling also antagonized AGEs-TGF-β1 induced fibroblast contraction, suggesting the existence of an inhibitory cross-talk mechanism between TGF-β1 and RAGE signaling. RAGE and TGF-β1 stimulated anti-inflammatory cytokines IL-2 and IL-4 expression. GM-CSF and IL-6 expression appeared to be dependent only on TGF-β1 signaling. Our data also indicated that IFN-γ upregulated in AGEs-BSA milieu in a RAGE and TGF-β1 independent mechanism. Our findings raise the possibility that RAGE and TGF-β1 are both involved in fibrosis development in a complex cross-talk mechanism, while also acting on their own individual targets. This study contributes to the understanding of impaired wound healing associated with diabetes complications.

RAGE and TLRs: relatives, friends or neighbours?

Science.gov (United States)

Ibrahim, Zaridatul Aini; Armour, Carol L; Phipps, Simon; Sukkar, Maria B

2013-12-01

The innate immune system forms the first line of protection against infectious and non-infectious tissue injury. Cells of the innate immune system detect pathogen-associated molecular patterns or endogenous molecules released as a result of tissue injury or inflammation through various innate immune receptors, collectively termed pattern-recognition receptors. Members of the Toll-like receptor (TLR) family of pattern-recognition receptors have well established roles in the host immune response to infection, while the receptor for advanced glycation end products (RAGE) is a pattern-recognition receptor predominantly involved in the recognition of endogenous molecules released in the context of infection, physiological stress or chronic inflammation. RAGE and TLRs share common ligands and signaling pathways, and accumulating evidence points towards their co-operative interaction in the host immune response. At present however, little is known about the mechanisms that result in TLR versus RAGE signalling or RAGE-TLR cross-talk in response to their shared ligands. Here we review what is known in relation to the physicochemical basis of ligand interactions between TLRs and RAGE, focusing on three shared ligands of these receptors: HMGB1, S100A8/A9 and LPS. Our aim is to discuss what is known about differential ligand interactions with RAGE and TLRs and to highlight important areas for further investigation so that we may better understand the role of these receptors and their relationship in host defense. Copyright © 2013 Elsevier Ltd. All rights reserved.

Age-dependent change of HMGB1 and DNA double-strand break accumulation in mouse brain

International Nuclear Information System (INIS)

Enokido, Yasushi; Yoshitake, Ayaka; Ito, Hikaru; Okazawa, Hitoshi

2008-01-01

HMGB1 is an evolutionarily conserved non-histone chromatin-associated protein with key roles in maintenance of nuclear homeostasis; however, the function of HMGB1 in the brain remains largely unknown. Recently, we found that the reduction of nuclear HMGB1 protein level in the nucleus associates with DNA double-strand break (DDSB)-mediated neuronal damage in Huntington's disease [M.L. Qi, K. Tagawa, Y. Enokido, N. Yoshimura, Y. Wada, K. Watase, S. Ishiura, I. Kanazawa, J. Botas, M. Saitoe, E.E. Wanker, H. Okazawa, Proteome analysis of soluble nuclear proteins reveals that HMGB1/2 suppress genotoxic stress in polyglutamine diseases, Nat. Cell Biol. 9 (2007) 402-414]. In this study, we analyze the region- and cell type-specific changes of HMGB1 and DDSB accumulation during the aging of mouse brain. HMGB1 is localized in the nuclei of neurons and astrocytes, and the protein level changes in various brain regions age-dependently. HMGB1 reduces in neurons, whereas it increases in astrocytes during aging. In contrast, DDSB remarkably accumulates in neurons, but it does not change significantly in astrocytes during aging. These results indicate that HMGB1 expression during aging is differentially regulated between neurons and astrocytes, and suggest that the reduction of nuclear HMGB1 might be causative for DDSB in neurons of the aged brain

HMGB1 and cord blood: its role as immuno-adjuvant factor in innate immunity.

Directory of Open Access Journals (Sweden)

Alessandra Ciucci

Full Text Available In newborn the innate immune system provides essential protection during primary infections before the generation of an appropriate adaptive immune response that is initially not fully operative. Innate immune response is evoked and perpetuated by molecules derived from microorganisms or by the damage/death of host cells. These are collectively known as damage-associated molecular-pattern (DAMP molecules. High-mobility group box 1 protein (HMGB1 or amphoterin, which previously was considered to be only a nuclear factor, has been recently identified as a DAMP molecule. When it is actively secreted by inflammatory cells or passively released from necrotic cells, HMGB1 mediates the response to infection, injury and inflammation, inducing dendritic cells maturation and T helper-1-cell responses. To characterize the role of HMGB1 in the innate and immature defense mechanisms in newborns, human cord blood (CB mononuclear cells, in comparison to adult peripheral blood (PB mononuclear cells, have been analyzed for its expression. By flow cytometry and western blot analysis, we observed that in CB and PB cells: i HMGB1 is expressed on cell surface membranes of myeloid dendritic cell precursors, mostly, and lymphocytes (gamma/delta and CD4(+ T cells to a lesser extent; ii different pro-inflammatory stimuli or molecules that mimic infection increased cell surface expression of HMGB1 as well as its secretion into extracellular environment; iii the treatment with synthetic molecules such as aminobisphosphonates (ABs, identified to be γδ T cell antigens, triggered up-regulation of HMGB1 expression on mononuclear cells, as well γδ T lymphocytes, inducing its secretion. The modulation of its secretion and the HMGB1-mediated migration of monocytes indicated HMGB1 as regulator of immune response in an immature system, like CB, through engagement of γδ T lymphocytes and myeloid dendritic cell precursors, essential components of innate immunity. In addition

HMGB1 mediates depressive behavior induced by chronic stress through activating the kynurenine pathway.

Science.gov (United States)

Wang, Bo; Lian, Yong-Jie; Su, Wen-Jun; Peng, Wei; Dong, Xin; Liu, Lin-Lin; Gong, Hong; Zhang, Ting; Jiang, Chun-Lei; Wang, Yun-Xia

2017-11-28

Our previous study has reported that the proactive secretion and role of central high mobility group box 1 (HMGB1) in lipopolysaccharide-induced depressive behavior. Here, the potential mechanism of HMGB1 mediating chronic-stress-induced depression through the kynurenine pathway (KP) was further explored both in vivo and in vitro. Depression model was established with the 4-week chronic unpredictable mild stress (CUMS). Sucrose preference and Barnes maze test were performed to reflect depressive behaviors. The ratio of kynurenine (KYN)/tryptophan (Trp) represented the enzyme activity of indoleamine-2,3-dioxygenase (IDO). Gene transcription and protein expression were assayed by real-time RT-PCR and western-blot or ELISA kit respectively. Along with depressive behaviors, HMGB1 concentrations in the hippocampus and serum substantially increased post 4-week CUMS exposure. Concurrent with the upregulated HMGB1 protein, the regulator of translocation of HMGB1, sirtuin 1 (SIRT1) concentration in the hippocampus remarkably increased. In addition to HMGB1 and SIRT1, IDO, the rate limiting enzyme of KP, was upregulated at the level of mRNA expression and enzyme activity in stressed hippocampi and LPS/HMGB1-treated hippocampal slices. The gene transcription of kynurenine monooxygenase (KMO) and kynureninase (KYNU) in the downstream of KP also increased both in vivo and in vitro. Mice treated with ethyl pyruvate (EP), the inhibitor of HMGB1 releasing, were observed with lower tendency of developing depressive behaviors and reduced activation of enzymes in KP. All of these experiments demonstrate that the role of HMGB1 on the induction of depressive behavior is mediated by KP activation. Copyright © 2017 Elsevier Inc. All rights reserved.

HMGB1/anti-HMGB1 antibodies define a molecular signature of early stages of HIV-Associated Neurocognitive Isorders (HAND

Directory of Open Access Journals (Sweden)

Marie-Lise Gougeon

2017-02-01

Conclusion: We report that brain injury in chronically HIV-infected patients on stable HAART is strongly associated with persistent CNS inflammation, which is correlated with increased levels of HMGB1 and anti-HMGB1 IgG in the CSF. Moreover, we identified circulating anti-HMGB1 IgG as a very early biomarker of neurological impairment in patients without HAND. These results might have important implication for the identification of patients who are at high risk of developing neurological disorders.

Long non-coding RNA UCA1 promotes lung cancer cell proliferation and migration via microRNA-193a/HMGB1 axis.

Science.gov (United States)

Wu, Hongyu; Zhou, Caicun

2018-02-05

Lung cancer is a leading cause of death worldwide. Long non-coding RNAs have been documented aberrantly expressed and exerted crucial role in variety of cancers. Urothelial carcinoma associated 1 (UCA1) is a potential new type of biomarkers for tumor diagnosis and exerts oncogenic effect on various human cancers. However, the mechanism of oncogenic role of UCA1 in lung cancer remains unclear. In this study, we firstly confirmed the role of UCA1 in lung cancer and found that UCA1 down-regulation inhibited cell proliferation and migration in both SKMES-1 and H520 lung cancer cells. Then we demonstrated that repressed UCA1 promoted the miR-193a expression and miR-193a could bind to the predicted binding site of UCA1. We then dissected the role of miR-193a in lung cancer and proved the anti-tumor role of miR-193a. Furthermore, we found that miR-193a displayed its role in lung cancer via modulating the HMGB1 expression. In addition, we found that over-expression of HMGB1 could restore the UCA1 knockdown induced repression of cell proliferation and migration. In summary, our study demonstrated that UCA1 exerts oncogenes activity in lung cancer, acting mechanistically by upregulating HMGB1 expression through 'sponging' miR-193a. Copyright © 2018 Elsevier Inc. All rights reserved.

Sequestering HMGB1 via DNA-Conjugated Beads Ameliorates Murine Colitis

Science.gov (United States)

Antoine, Daniel J.; Dancho, Meghan; Tsaava, Teá; Li, Jianhua; Lu, Ben; Levine, Yaakov A.; Stiegler, Andrew; Tamari, Yehuda; Al-Abed, Yousef; Roth, Jesse; Tracey, Kevin J.; Yang, Huan

2014-01-01

Inflammatory bowel disease (IBD) is chronic inflammation of the gastrointestinal tract that affects millions of people worldwide. Although the etiology of IBD is not clear, it is known that products from stressed cells and enteric microbes promote intestinal inflammation. High mobility group box 1 (HMGB1), originally identified as a nuclear DNA binding protein, is a cytokine-like protein mediator implicated in infection, sterile injury, autoimmune disease, and IBD. Elevated levels of HMGB1 have been detected in inflamed human intestinal tissues and in feces of IBD patients and mouse models of colitis. Neutralizing HMGB1 activity by administration of anti-HMGB1 antibodies or HMGB1-specific antagonist improves clinical outcomes in animal models of colitis. Since HMGB1 binds to DNA with high affinity, here we developed a novel strategy to sequester HMGB1 using DNA immobilized on sepharose beads. Screening of DNA-bead constructs revealed that B2 beads, one linear form of DNA conjugated beads, bind HMGB1 with high affinity, capture HMGB1 ex vivo from endotoxin-stimulated RAW 264.7 cell supernatant and from feces of mice with colitis. Oral administration of B2 DNA beads significantly improved body weight, reduced colon injury, and suppressed colonic and circulating cytokine levels in mice with spontaneous colitis (IL-10 knockout) and with dextran sulfate sodium-induced colitis. Thus, DNA beads reduce inflammation by sequestering HMGB1 and may have therapeutic potential for the treatment of IBD. PMID:25127031

The Expression of HMGB1 in Bone Marrow MSCs Is Upregulated by Hypoxia with Regulatory Effects on the Apoptosis and Adhesion

Directory of Open Access Journals (Sweden)

Mei-Yun Tan

2016-01-01

Full Text Available Background and Aims. Hypoxia regulates the survival of mesenchymal stem cells (MSCs but the mechanism is unclear. In hypoxia, the level of high mobility group box 1 (HMGB1 was increased in many cells which may be involved in the regulation of cell biology. The aim is to determine whether hypoxia affects the expression of HMGB1 in bone marrow MSCs (BM-MSCs and to investigate the role of HMGB1 in the apoptosis and adhesion. Methods. BM-MSCs were exposed to hypoxia (1% O2 and normoxia (20% O2 and the expression of HMGB1 was measured by RT-PCR and western blotting. The apoptosis and adhesion of BM-MSCs were evaluated after interfered by different concentrations of HMGB1. Results. Expression of HMGB1 in BM-MSCs showed a significant upregulation in hypoxia when compared to those in normoxia. The adhesion of BM-MSCs was increased by HMGB1 in a concentration-dependent manner; the apoptosis effect of HMGB1 depended on its concentrations: HMGB1 at low concentration (50 ng/mL promoted the apoptosis of BM-MSCs while HMGB1 at high concentration (≥100 ng/mL reduced this apoptosis. Conclusions. Hypoxia enhanced the expression of HMGB1 in BM-MSCs with influences on apoptosis and adhesion and this could have a significant effect on the regenerative potential of MSC-based strategies.

Curcumin longa extract-loaded nanoemulsion improves the survival of endotoxemic mice by inhibiting nitric oxide-dependent HMGB1 release.

Science.gov (United States)

Ahn, Min Young; Hwang, Jung Seok; Lee, Su Bi; Ham, Sun Ah; Hur, Jinwoo; Kim, Jun Tae; Seo, Han Geuk

2017-01-01

High mobility group box 1 (HMGB1) is a well-known damage-related alarmin that participates in cellular inflammatory responses. However, the mechanisms leading to HMGB1 release in inflammatory conditions and the therapeutic agents that could prevent it remain poorly understood. This study attempted to examine whether the Curcumin longa herb, which is known to have anti-inflammatory property, can modulate cellular inflammatory responses by regulating HMGB1 release. The murine macrophage RAW264.7 cells were treated with lipopolysaccharide (LPS) and/or a C. longa extract-loaded nanoemulsion (CLEN). The levels of released HMGB1, nitric oxide (NO) production, inducible NO synthase (iNOS) expression, and phosphorylation of mitogen-activated protein kinases were analyzed in RAW264.7 macrophages. The effects of CLEN on survival of endotoxemic model mice, circulating HMGB1 levels, and tissue iNOS expression were also evaluated. We have shown that a nanoemulsion loaded with an extract from the C. longa rhizome regulates cellular inflammatory responses and LPS-induced systemic inflammation by suppressing the release of HMGB1 by macrophages. First, treatment of RAW264.7 macrophages with the nanoemulsion significantly attenuated their LPS-induced release of HMGB1: this effect was mediated by inhibiting c-Jun N-terminal kinase activation, which in turn suppressed the NO production and iNOS expression of the cells. The nanoemulsion did not affect LPS-induced p38 or extracellular signal-regulated kinase activation. Second, intraperitoneal administration of the nanoemulsion improved the survival rate of LPS-injected endotoxemic mice. This associated with marked reductions in circulating HMGB1 levels and tissue iNOS expression. The present study shows for the first time the mechanism by which C. longa ameliorates sepsis, namely, by suppressing NO signaling and thereby inhibiting the release of the proinflammatory cytokine HMGB1. These observations suggest that identification of

Curcumin longa extract-loaded nanoemulsion improves the survival of endotoxemic mice by inhibiting nitric oxide-dependent HMGB1 release

Directory of Open Access Journals (Sweden)

Min Young Ahn

2017-09-01

Full Text Available Background High mobility group box 1 (HMGB1 is a well-known damage-related alarmin that participates in cellular inflammatory responses. However, the mechanisms leading to HMGB1 release in inflammatory conditions and the therapeutic agents that could prevent it remain poorly understood. This study attempted to examine whether the Curcumin longa herb, which is known to have anti-inflammatory property, can modulate cellular inflammatory responses by regulating HMGB1 release. Methods The murine macrophage RAW264.7 cells were treated with lipopolysaccharide (LPS and/or a C. longa extract-loaded nanoemulsion (CLEN. The levels of released HMGB1, nitric oxide (NO production, inducible NO synthase (iNOS expression, and phosphorylation of mitogen-activated protein kinases were analyzed in RAW264.7 macrophages. The effects of CLEN on survival of endotoxemic model mice, circulating HMGB1 levels, and tissue iNOS expression were also evaluated. Results We have shown that a nanoemulsion loaded with an extract from the C. longa rhizome regulates cellular inflammatory responses and LPS-induced systemic inflammation by suppressing the release of HMGB1 by macrophages. First, treatment of RAW264.7 macrophages with the nanoemulsion significantly attenuated their LPS-induced release of HMGB1: this effect was mediated by inhibiting c-Jun N-terminal kinase activation, which in turn suppressed the NO production and iNOS expression of the cells. The nanoemulsion did not affect LPS-induced p38 or extracellular signal-regulated kinase activation. Second, intraperitoneal administration of the nanoemulsion improved the survival rate of LPS-injected endotoxemic mice. This associated with marked reductions in circulating HMGB1 levels and tissue iNOS expression. Discussion The present study shows for the first time the mechanism by which C. longa ameliorates sepsis, namely, by suppressing NO signaling and thereby inhibiting the release of the proinflammatory cytokine HMGB1

HMGB1 Promotes Systemic Lupus Erythematosus by Enhancing Macrophage Inflammatory Response

Directory of Open Access Journals (Sweden)

Mudan Lu

2015-01-01

Full Text Available Background/Purpose. HMGB1, which may act as a proinflammatory mediator, has been proposed to contribute to the pathogenesis of multiple chronic inflammatory and autoimmune diseases including systemic lupus erythematosus (SLE; however, the precise mechanism of HMGB1 in the pathogenic process of SLE remains obscure. Method. The expression of HMGB1 was measured by ELISA and western blot. The ELISA was also applied to detect proinflammatory cytokines levels. Furthermore, nephritic pathology was evaluated by H&E staining of renal tissues. Results. In this study, we found that HMGB1 levels were significantly increased and correlated with SLE disease activity in both clinical patients and murine model. Furthermore, gain- and loss-of-function analysis showed that HMGB1 exacerbated the severity of SLE. Of note, the HMGB1 levels were found to be associated with the levels of proinflammatory cytokines such as TNF-α and IL-6 in SLE patients. Further study demonstrated that increased HMGB1 expression deteriorated the severity of SLE via enhancing macrophage inflammatory response. Moreover, we found that receptor of advanced glycation end products played a critical role in HMGB1-mediated macrophage inflammatory response. Conclusion. These findings suggested that HMGB1 might be a risk factor for SLE, and manipulation of HMGB1 signaling might provide a therapeutic strategy for SLE.

Antisense RNA Controls LRP1 Sense Transcript Expression through Interaction with a Chromatin-Associated Protein, HMGB2

Directory of Open Access Journals (Sweden)

Yasunari Yamanaka

2015-05-01

Full Text Available Long non-coding RNAs (lncRNAs, including natural antisense transcripts (NATs, are expressed more extensively than previously anticipated and have widespread roles in regulating gene expression. Nevertheless, the molecular mechanisms of action of the majority of NATs remain largely unknown. Here, we identify a NAT of low-density lipoprotein receptor-related protein 1 (Lrp1, referred to as Lrp1-AS, that negatively regulates Lrp1 expression. We show that Lrp1-AS directly binds to high-mobility group box 2 (Hmgb2 and inhibits the activity of Hmgb2 to enhance Srebp1a-dependent transcription of Lrp1. Short oligonucleotides targeting Lrp1-AS inhibit the interaction of antisense transcript and Hmgb2 protein and increase Lrp1 expression by enhancing Hmgb2 activity. Quantitative RT-PCR analysis of brain tissue samples from Alzheimer’s disease patients and aged-matched controls revealed upregulation of LRP1-AS and downregulation of LRP1. Our data suggest a regulatory mechanism whereby a NAT interacts with a ubiquitous chromatin-associated protein to modulate its activity in a locus-specific fashion.

Anti-high mobility group box-1 antibody therapy for traumatic brain injury.

Science.gov (United States)

Okuma, Yu; Liu, Keyue; Wake, Hidenori; Zhang, Jiyong; Maruo, Tomoko; Date, Isao; Yoshino, Tadashi; Ohtsuka, Aiji; Otani, Naoki; Tomura, Satoshi; Shima, Katsuji; Yamamoto, Yasuhiko; Yamamoto, Hiroshi; Takahashi, Hideo K; Mori, Shuji; Nishibori, Masahiro

2012-09-01

High mobility group box-1 (HMGB1) plays an important role in triggering inflammatory responses in many types of diseases. In this study, we examined the involvement of HMGB1 in traumatic brain injury (TBI) and evaluated the ability of intravenously administered neutralizing anti-HMGB1 monoclonal antibody (mAb) to attenuate brain injury. Traumatic brain injury was induced in rats or mice by fluid percussion. Anti-HMGB1 mAb or control mAb was administered intravenously after TBI. Anti-HMGB1 mAb remarkably inhibited fluid percussion-induced brain edema in rats, as detected by T2-weighted magnetic resonance imaging; this was associated with inhibition of HMGB1 translocation, protection of blood-brain barrier (BBB) integrity, suppression of inflammatory molecule expression, and improvement of motor function. In contrast, intravenous injection of recombinant HMGB1 dose-dependently produced the opposite effects. Experiments using receptor for advanced glycation end product (RAGE)(-/-) , toll-like receptor-4 (TLR4)(-/-) , and TLR2(-/-) mice suggested the involvement of RAGE as the predominant receptor for HMGB1. Anti-HMGB1 mAb may provide a novel and effective therapy for TBI by protecting against BBB disruption and reducing the inflammatory responses induced by HMGB1. Copyright © 2012 American Neurological Association.

HMGB1 promotes the development of pulmonary arterial hypertension in rats.

Directory of Open Access Journals (Sweden)

Yukari Sadamura-Takenaka

Full Text Available Pulmonary arterial hypertension (PAH is characterized by increased pulmonary vascular resistance leading to right ventricular failure and death. Recent studies have suggested that chronic inflammatory processes are involved in the pathogenesis of PAH. However, the molecular and cellular mechanisms driving inflammation have not been fully elucidated.To elucidate the roles of high mobility group box 1 protein (HMGB1, a ubiquitous DNA-binding protein with extracellular pro-inflammatory activity, in a rat model of PAH.Male Sprague-Dawley rats were administered monocrotaline (MCT. Concentrations of HMGB1 in bronchoalveolar lavage fluid (BALF and serum, and localization of HMGB1 in the lung were examined over time. The protective effects of anti-HMGB1 neutralizing antibody against MCT-induced PAH were tested.HMGB1 levels in BALF were elevated 1 week after MCT injection, and this elevation preceded increases of other pro-inflammatory cytokines, such as TNF-α, and the development of PAH. In contrast, serum HMGB1 levels were elevated 4 weeks after MCT injection, at which time the rats began to die. Immunohistochemical analyses indicated that HMGB1 was translocated to the extranuclear space in periarterial infiltrating cells, alveolar macrophages, and bronchial epithelial cells of MCT-injected rats. Anti-HMGB1 neutralizing antibody protected rats against MCT-induced lung inflammation, thickening of the pulmonary artery wall, and elevation of right ventricular systolic pressure, and significantly improved the survival of the MCT-induced PAH rats.Our results identify extracellular HMGB1 as a promoting factor for MCT-induced PAH. The blockade of HMGB1 activity improved survival of MCT-induced PAH rats, and thus might be a promising therapy for the treatment of PAH.

The chaperone like function of the nonhistone protein HMGB1

International Nuclear Information System (INIS)

Osmanov, Taner; Ugrinova, Iva; Pasheva, Evdokia

2013-01-01

Highlights: ► The HMGB1 protein strongly enhanced the formation of nucleosome particles. ► The target of HMGB1 action as a chaperone is the DNA not the histone octamer. ► The acetylation of HMGB1 decreases the stimulating effect of the protein. -- Abstract: Almost all essential nuclear processes as replication, repair, transcription and recombination require the chromatin template to be correctly unwound and than repackaged. The major strategy that the cell uses to overcome the nucleosome barrier is the proper removal of the histone octamer and subsequent deposition onto DNA. Important factors in this multi step phenomenon are the histone chaperones that can assemble nucleosome arrays in vitro in the absence of ATP. The nonhistone protein HMGB1 is a good candidate for a chaperone as its molecule consists of two DNA binding motives, Box’s A and B, and a long nonstructured C tail highly negatively charged. HMGB1 protein is known as a nuclear “architectural” factor for its property to bind preferentially to distorted DNA structures and was reported to kink the double helix. Our experiments show that in the classical stepwise dialysis method for nucleosome assembly the addition of HMGB1 protein stimulates more than two times the formation of middle-positioned nucleosomes. The stimulation effect persists in dialysis free experiment when the reconstitution is possible only in the presence of a chaperone. The addition of HMGB1 protein strongly enhanced the formation of a nucleosome in a dose dependant manner. Our results show that the target of HMGB1 action as a chaperone is the DNA fragment not the histone octamer. One possible explanation for the stimulating effect of HMGB1 is the “architectural” property of the protein to associate with the middle of the DNA fragment and to kink it. The acquired V shaped DNA structure is probably conformationals more favorable to wrap around the prefolded histone octamer. We tested also the role of the post

RAGE mediates the inactivation of nAChRs in sympathetic neurons under high glucose conditions.

Science.gov (United States)

Chandna, Andrew R; Nair, Manoj; Chang, Christine; Pennington, Paul R; Yamamoto, Yasuhiko; Mousseau, Darrell D; Campanucci, Verónica A

2015-02-01

Autonomic dysfunction is a serious complication of diabetes and can lead to cardiovascular abnormalities and premature death. It was recently proposed that autonomic dysfunction is triggered by oxidation-mediated inactivation of neuronal nicotinic acetylcholine receptors (nAChRs), impairing synaptic transmission in sympathetic ganglia and resulting in autonomic failure. We investigated whether the receptor for advanced glycation end products (RAGE) and its role in the generation of reactive oxygen species (ROS) could be contributing to the events that initiate sympathetic malfunction under high glucose conditions. Using biochemical, live imaging and electrophysiological tools we demonstrated that exposure of sympathetic neurons to high glucose increases RAGE expression and oxidative markers, and that incubation with RAGE ligands (e.g. AGEs, S100 and HMGB1) mimics both ROS elevation and nAChR inactivation. In contrast, co-treatment with either antioxidants or an anti-RAGE IgG prevented the inactivation of nAChRs. Lastly, a role for RAGE in this context was corroborated by the lack of sensitivity of sympathetic neurons from RAGE knock-out mice to high glucose. These data define a pivotal role for RAGE in initiating the events associated with exposure of sympathetic neurons to high glucose, and strongly support RAGE signaling as a potential therapeutic target in the autonomic complications associated with diabetes. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Block effect on HCV infection by HMGB1 released from virus-infected cells: An insight from mathematical modeling

Science.gov (United States)

Wang, Wei; Ma, Wanbiao

2018-06-01

The nuclear protein high-mobility group box 1 (HMGB1) can have an active role in deoxyribonucleic acid (DNA) organization and the regulation of transcription. Based on the new findings from a recent experimental study, the blocking effect on HCV infection by HMGB1 released from virus-infected cells is investigated using a diffusive model for viral infection dynamics. In the model, the diffusion of the virus depends not only on its concentration gradient, but also on the concentration of HMGB1. The basic reproduction number, threshold dynamics, stability properties of the steady states, travelling wave solutions, and spreading speed for the proposed model are studied. We show that the HMGB1-induced blocking of HCV infection slows the spread of virus compared with random diffusion only. Numerically, it is shown that a high concentration of HMGB1 can block the spread of virus and this confirms, not only qualitatively but also quantitatively, the experimental result.

Involvement of high mobility group box 1 in the development and maintenance of chemotherapy-induced peripheral neuropathy in rats

International Nuclear Information System (INIS)

Nishida, Takeshi; Tsubota, Maho; Kawaishi, Yudai; Yamanishi, Hiroki; Kamitani, Natsuki; Sekiguchi, Fumiko; Ishikura, Hiroyasu; Liu, Keyue; Nishibori, Masahiro; Kawabata, Atsufumi

2016-01-01

Given that high mobility group box 1 (HMGB1), a nuclear protein, once released to the extracellular space, promotes nociception, we asked if inactivation of HMGB1 prevents or reverses chemotherapy-induced painful neuropathy in rats and also examined possible involvement of Toll-like receptor 4 (TLR4) and the receptor for advanced glycation endproduct (RAGE), known as targets for HMGB1. Painful neuropathy was produced by repeated i.p. administration of paclitaxel or vincristine in rats. Nociceptive threshold was determined by the paw pressure method and/or von Frey test in the hindpaw. Tissue protein levels were determined by immunoblotting. Repeated i.p. administration of the anti-HMGB1-neutralizing antibody or recombinant human soluble thrombomodulin (rhsTM), known to inactivate HMGB1, prevented the development of hyperalgesia and/or allodynia induced by paclitaxel or vincristine in rats. A single i.p. or intraplantar (i.pl.) administration of the antibody or rhsTM reversed the chemotherapy-induced neuropathy. A single i.pl. administration of a TLR4 antagonist or low molecular weight heparin, known to inhibit RAGE, attenuated the hyperalgesia caused by i.pl. HMGB1 and also the chemotherapy-induced painful neuropathy. Paclitaxel or vincristine treatment significantly decreased protein levels of HMGB1 in the dorsal root ganglia, but not sciatic nerves. HMGB1 thus participates in both development and maintenance of chemotherapy-induced painful neuropathy, in part through RAGE and TLR4. HMGB1 inactivation is considered useful to prevent and treat the chemotherapy-induced painful neuropathy.

MCPIP1-induced autophagy mediates ischemia/reperfusion injury in endothelial cells via HMGB1 and CaSR.

Science.gov (United States)

Xie, Xiaolong; Zhu, Tiebing; Chen, Lulu; Ding, Shuang; Chu, Han; Wang, Jing; Yao, Honghong; Chao, Jie

2018-01-29

Monocyte chemotactic protein-1-induced protein 1 (MCPIP1) plays a important role in ischemia/reperfusion (I/R) injury. Autophagy is involved in activating endothelial cells in response to I/R. However, researchers have not clearly determined whether MCPIP1 mediates I/R injury in endothelial cells via autophagy, and its downstream mechanism remains unclear. Western blotting analyses and immunocytochemistry were applied to detect protein levels were detected in HUVECs. An in vitro scratch assay was used to detect cell migration. Cells were transfected with siRNAs to knockdown MCPIP1 and high mobility group box 1 (HMGB1) expression. The pharmacological activator of autophagy rapamycin and the specific calcium-sensing receptor (CaSR) inhibitor NPS-2143 were used to confirm the roles of autophagy and CaSR in I/R injury. I/R induced HMGB1 and CaSR expression, which subsequently upreguated the migration and apoptosis of HUVECs and coincided with the increase of autophagy. HMGB1 was involved in cell migration, whereas CaSR specifically participated in I/R-induced HUVEC apoptosis. Based on these findings, I/R-induced MCPIP1 expression regulates the migration and apoptosis of HUVECs via HMGB1 and CaSR, respectively, suggesting a new therapeutic targetof I/R injury.

CK2 Phosphorylation of Schistosoma mansoni HMGB1 Protein Regulates Its Cellular Traffic and Secretion but Not Its DNA Transactions

OpenAIRE

de Abreu da Silva, Isabel Caetano; Carneiro, Vitor Coutinho; Maciel, Renata de Moraes; da Costa, Rodrigo Furtado Madeiro; Furtado, Daniel Rodrigues; de Oliveira, Francisco Meirelles Bastos; da Silva-Neto, Mário Alberto Cardoso; Rumjanek, Franklin David; Fantappié, Marcelo Rosado

2011-01-01

BACKGROUND: The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding t...

The extracellular release of Schistosoma mansoni HMGB1 nuclear protein is mediated by acetylation

International Nuclear Information System (INIS)

Coutinho Carneiro, Vitor; Moraes Maciel, Renata de; Caetano de Abreu da Silva, Isabel; Furtado Madeira da Costa, Rodrigo; Neto Paiva, Claudia; Torres Bozza, Marcelo; Rosado Fantappie, Marcelo

2009-01-01

Schistosoma mansoni HMGB1 (SmHMGB1) was revealed to be a substrate for the parasite histone acetyltransferases SmGCN5 and SmCBP1. We found that full-length SmHMGB1, as well as its HMG-box B (but not HMG-box A) were acetylated in vitro by SmGCN5 and SmCBP1. However, SmCBP1 was able to acetylate both substrates more efficiently than SmGCN5. Interestingly, the removal of the C-terminal acidic tail of SmHMGB1 (SmHMGB1ΔC) resulted in increased acetylation of the protein. We showed by mammalian cell transfection assays that SmHMGB1 and SmHMGB1ΔC were transported from the nucleus to the cytoplasm after sodium butyrate (NaB) treatment. Importantly, after NaB treatment, SmHMGB1 was also present outside the cell. Together, our data suggest that acetylation of SmHMGB1 plays a role in cellular trafficking, culminating with its secretion to the extracellular milieu. The possible role of SmHMGB1 acetylation in the pathogenesis of schistosomiasis is discussed.

The extracellular release of Schistosoma mansoni HMGB1 nuclear protein is mediated by acetylation

Energy Technology Data Exchange (ETDEWEB)

Coutinho Carneiro, Vitor; Moraes Maciel, Renata de; Caetano de Abreu da Silva, Isabel; Furtado Madeira da Costa, Rodrigo [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Neto Paiva, Claudia; Torres Bozza, Marcelo [Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Goes, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Rosado Fantappie, Marcelo, E-mail: fantappie@bioqmed.ufrj.br [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil)

2009-12-25

Schistosoma mansoni HMGB1 (SmHMGB1) was revealed to be a substrate for the parasite histone acetyltransferases SmGCN5 and SmCBP1. We found that full-length SmHMGB1, as well as its HMG-box B (but not HMG-box A) were acetylated in vitro by SmGCN5 and SmCBP1. However, SmCBP1 was able to acetylate both substrates more efficiently than SmGCN5. Interestingly, the removal of the C-terminal acidic tail of SmHMGB1 (SmHMGB1{Delta}C) resulted in increased acetylation of the protein. We showed by mammalian cell transfection assays that SmHMGB1 and SmHMGB1{Delta}C were transported from the nucleus to the cytoplasm after sodium butyrate (NaB) treatment. Importantly, after NaB treatment, SmHMGB1 was also present outside the cell. Together, our data suggest that acetylation of SmHMGB1 plays a role in cellular trafficking, culminating with its secretion to the extracellular milieu. The possible role of SmHMGB1 acetylation in the pathogenesis of schistosomiasis is discussed.

Expression analysis of HMGB1 in histological samples of malignant pleural mesothelioma.

Science.gov (United States)

Rrapaj, Eltjona; Trisolini, Elena; Bertero, Luca; Salvo, Michela; Indellicato, Rossella; Andorno, Silvano; Garcia-Manteiga, Jose M; Rena, Ottavio; Boldorini, Renzo L

2018-05-01

High mobility group box 1 (HMGB1) is a chromatin structural protein, expressed ubiquitously in the nuclei of mammalian cells. When transported extracellularly, it acts as a tumour suppressor and oncogenic protein. In malignant pleural mesothelioma (MPM), high serum levels of HMGB1 have been related to a poor prognosis. Conversely, the significance of HMGB1 expression in MPM tissues is still unclear. Biopsy samples from 170 patients with MPM were assessed by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to evaluate HMGB1 protein and gene expression. The expression level of HMGB1 protein was scored using a semiquantitative system that sums the intensity (0-3) and the percentage (from 0 to 4) of positively stained cells in nuclei, cytoplasm and in both. The final score was considered as high (>3) or low (<3) expression. Gene expression levels were calculated using the ΔΔC t method. High expression levels of HMGB1 as total (P = 0.0011) and cytoplasmic score (P = 0.0462) were related to a worse disease-specific survival (DSS) in the entire cohort and in the clinicopathological subgroups. No significant correlation was found between HMGB1 gene expression and DSS. These findings indicate that HMGB1 may be a useful prognostic biomarker in MPM when detected by immunohistochemistry. Conversely, as it is also expressed in normal and reactive mesothelial cells, HMGB1 cannot be considered a diagnostic biomarker in histological samples of mesothelioma. © 2018 John Wiley & Sons Ltd.

Binding of histone H1 to DNA is differentially modulated by redox state of HMGB1.

Directory of Open Access Journals (Sweden)

Eva Polanská

Full Text Available HMGB1 is an architectural protein in chromatin, acting also as a signaling molecule outside the cell. Recent reports from several laboratories provided evidence that a number of both the intracellular and extracellular functions of HMGB1 may depend on redox-sensitive cysteine residues of the protein. In this study we demonstrate that redox state of HMGB1 can significantly modulate the ability of the protein to bind and bend DNA, as well as to promote DNA end-joining. We also report a high affinity binding of histone H1 to hemicatenated DNA loops and DNA minicircles. Finally, we show that reduced HMGB1 can readily displace histone H1 from DNA, while oxidized HMGB1 has limited capacity for H1 displacement. Our results suggested a novel mechanism for the HMGB1-mediated modulation of histone H1 binding to DNA. Possible biological consequences of linker histones H1 replacement by HMGB1 for the functioning of chromatin are discussed.

The potential role of HMGB1 release in peritoneal dialysis-related peritonitis.

Directory of Open Access Journals (Sweden)

Shirong Cao

Full Text Available High mobility group box 1 (HMGB1, a DNA-binding nuclear protein, has been implicated as an endogenous danger signal in the pathogenesis of infection diseases. However, the potential role and source of HMGB1 in the peritoneal dialysis (PD effluence of patients with peritonitis are unknown. First, to evaluate HMDB1 levels in peritoneal dialysis effluence (PDE, a total of 61 PD patients were enrolled in this study, including 42 patients with peritonitis and 19 without peritonitis. Demographic characteristics, symptoms, physical examination findings and laboratory parameters were recorded. HMGB1 levels in PDE were determined by Western blot and ELISA. The concentrations of TNF-α and IL-6 in PDE were quantified by ELISA. By animal model, inhibition of HMGB1 with glycyrrhizin was performed to determine the effects of HMGB1 in LPS-induced mice peritonitis. In vitro, a human peritoneal mesothelial cell line (HMrSV5 was stimulated with lipopolysaccharide (LPS, HMGB1 extracellular content in the culture media and intracellular distribution in various cellular fractions were analyzed by Western blot or immunofluorescence. The results showed that the levels of HMGB1 in PDE were higher in patients with peritonitis than those in controls, and gradually declined during the period of effective antibiotic treatments. Furthermore, the levels of HMGB1 in PDE were positively correlated with white blood cells (WBCs count, TNF-α and IL-6 levels. However, pretreatment with glycyrrhizin attenuated LPS-induced acute peritoneal inflammation and dysfunction in mice. In cultured HMrSV5 cells, LPS actively induced HMGB1 nuclear-cytoplasmic translocation and release in a time and dose-dependent fashion. Moreover, cytosolic HMGB1 was located in lysosomes and secreted via a lysosome-mediated secretory pathway following LPS stimulation. Our study demonstrates that elevated HMGB1 levels in PDE during PD-related peritonitis, at least partially, from peritoneal mesothelial cells

Lithium chloride attenuates mitomycin C induced necrotic cell death in MDA-MB-231 breast cancer cells via HMGB1 and Bax signaling.

Science.gov (United States)

Razmi, Mahdieh; Rabbani-Chadegani, Azra; Hashemi-Niasari, Fatemeh; Ghadam, Parinaz

2018-07-01

The clinical use of potent anticancer drug mitomycin C (MMC) has limited due to side effects and resistance of cancer cells. The aim of this study was to investigate whether lithium chloride (LiCl), as a mood stabilizer, can affect the sensitivity of MDA-MB-231 breast cancer cells to mitomycin C. The cells were exposed to various concentrations of mitomycin C alone and combined with LiCl and the viability determined by trypan blue and MTT assays. Proteins were analyzed by western blot and mRNA expression of HMGB1 MMP9 and Bcl-2 were analyzed by RT-PCR. Flow cytometry was used to determine the cell cycle arrest and percent of apoptotic and necrotic cells. Concentration of Bax assessed by ELISA. Exposure of the cells to mitomycin C revealed IC 50 value of 20 μM, whereas pretreatment of the cells with LiCl induced synergistic cytotoxicity and IC 50 value declined to 5 μM. LiCl combined with mitomycin C significantly down-regulated HMGB1, MMP9 and Bcl-2 gene expression but significantly increased the level of Bax protein. In addition, the content of HMGB1 in the nuclei decreased and pretreatment with LiCl reduced the content of HMGB1 release induced by MMC. LiCl increased mitomycin C-induced cell shrinkage and PARP fragmentation suggesting induction of apoptosis in these cells. LiCl prevented mitomycin C-induced necrosis and changed the cell death arrest at G2/M-phase. Taking all together, it is suggested that LiCl efficiently enhances mitomycin C-induced apoptosis and HMGB1, Bax and Bcl-2 expression may play a major role in this process, the findings that provide a new therapeutic strategy for LiCl in combination with mitomycin C. Copyright © 2018 Elsevier GmbH. All rights reserved.

Omega-3 polyunsaturated fatty acid attenuates the inflammatory response by modulating microglia polarization through SIRT1-mediated deacetylation of the HMGB1/NF-κB pathway following experimental traumatic brain injury.

Science.gov (United States)

Chen, Xiangrong; Chen, Chunnuan; Fan, Sining; Wu, Shukai; Yang, Fuxing; Fang, Zhongning; Fu, Huangde; Li, Yasong

2018-04-20

Microglial polarization and the subsequent neuroinflammatory response are contributing factors for traumatic brain injury (TBI)-induced secondary injury. High mobile group box 1 (HMGB1) mediates the activation of the NF-κB pathway, and it is considered to be pivotal in the late neuroinflammatory response. Activation of the HMGB1/NF-κB pathway is closely related to HMGB1 acetylation, which is regulated by the sirtuin (SIRT) family of proteins. Omega-3 polyunsaturated fatty acids (ω-3 PUFA) are known to have antioxidative and anti-inflammatory effects. We previously demonstrated that ω-3 PUFA inhibited TBI-induced microglial activation and the subsequent neuroinflammatory response by regulating the HMGB1/NF-κB signaling pathway. However, no studies have elucidated if ω-3 PUFA affects the HMGB1/NF-κB pathway in a HMGB1 deacetylation of dependent SIRT1 manner, thus regulating microglial polarization and the subsequent neuroinflammatory response. The Feeney DM TBI model was adopted to induce brain injury in rats. Modified neurological severity scores, rotarod test, brain water content, and Nissl staining were employed to determine the neuroprotective effects of ω-3 PUFA supplementation. Assessment of microglia polarization and pro-inflammatory markers, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and HMGB1, were used to evaluate the neuroinflammatory responses and the anti-inflammatory effects of ω-3 PUFA supplementation. Immunofluorescent staining and western blot analysis were used to detect HMGB1 nuclear translocation, secretion, and HMGB1/NF-κB signaling pathway activation to evaluate the effects of ω-3 PUFA supplementation. The impact of SIRT1 deacetylase activity on HMGB1 acetylation and the interaction between HMGB1 and SIRT1 were assessed to evaluate anti-inflammation effects of ω-3 PUFAs, and also, whether these effects were dependent on a SIRT1-HMGB1/NF-κB axis to gain further insight into the mechanisms underlying the

High-Mobility Group Box 1 Mediates Fibroblast Activity via RAGE-MAPK and NF-κB Signaling in Keloid Scar Formation

Directory of Open Access Journals (Sweden)

Jihee Kim

2017-12-01

Full Text Available Emerging studies have revealed the involvement of high-mobility group box 1 (HMGB1 in systemic fibrotic diseases, yet its role in the cutaneous scarring process has not yet been investigated. We hypothesized that HMGB1 may promote fibroblast activity to cause abnormal cutaneous scarring. In vitro wound healing assay with normal and keloid fibroblasts demonstrated that HMGB1 administration promoted the migration of both fibroblasts with increased speed and a greater traveling distance. Treatment of the HMGB1 inhibitor glycyrrhizic acid (GA showed an opposing effect on both activities. To analyze the downstream mechanism, the protein levels of extracellular signal-regulated kinase (ERK 1/2, protein kinase B (AKT, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB were measured by western blot analysis. HMGB1 increased the expression levels of ERK1/2, AKT, and NF-κB compared to the control, which was suppressed by GA. HMGB1 promoted both normal and keloid fibroblasts migration to a degree equivalent to that achieved with TGF-β. We concluded that HMGB1 activates fibroblasts via the receptor for advanced glycation end product (RAGE—mitogen-activated protein kinases (MAPK and NF-κB interaction signaling pathways. Further knowledge of the relationship of HMGB1 with skin fibrosis may lead to a promising clinical approach to manage abnormal scarring.

Intracellular high mobility group B1 protein (HMGB1) represses HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

International Nuclear Information System (INIS)

Naghavi, Mojgan H.; Nowak, Piotr; Andersson, Jan; Soennerborg, Anders; Yang Huan; Tracey, Kevin J.; Vahlne, Anders

2003-01-01

We investigated whether the high mobility group B 1 (HMGB1), an abundant nuclear protein in all mammalian cells, affects HIV-1 transcription. Intracellular expression of human HMGB1 repressed HIV-1 gene expression in epithelial cells. This inhibitory effect of HMGB1 was caused by repression of long terminal repeat (LTR)-mediated transcription. Other viral promoters/enhancers, including simian virus 40 or cytomegalovirus, were not inhibited by HMGB1. In addition, HMGB1 inhibition of HIV-1 subtype C expression was dependent on the number of NFκB sites in the LTR region. The inhibitory effect of HMGB1 on viral gene expression observed in HeLa cells was confirmed by an upregulation of viral replication in the presence of antisense HMGB1 in monocytic cells. In contrast to what was found in HeLa cells and monocytic cells, endogenous HMGB1 expression did not affect HIV-1 replication in unstimulated Jurkat cells. Thus, intracellular HMGB1 affects HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

HMGB1 Is a Potential Biomarker for Severe Viral Hemorrhagic Fevers.

Directory of Open Access Journals (Sweden)

Katarina Resman Rus

2016-06-01

Full Text Available Hemorrhagic fever with renal syndrome (HFRS and Crimean-Congo hemorrhagic fever (CCHF are common representatives of viral hemorrhagic fevers still often neglected in some parts of the world. Infection with Dobrava or Puumala virus (HFRS and Crimean-Congo hemorrhagic fever virus (CCHFV can result in a mild, nonspecific febrile illness or as a severe disease with hemorrhaging and high fatality rate. An important factor in optimizing survival rate in patients with VHF is instant recognition of the severe form of the disease for which significant biomarkers need to be elucidated. To determine the prognostic value of High Mobility Group Box 1 (HMGB1 as a biomarker for disease severity, we tested acute serum samples of patients with HFRS or CCHF. Our results showed that HMGB1 levels are increased in patients with CCHFV, DOBV or PUUV infection. Above that, concentration of HMGB1 is higher in patients with severe disease progression when compared to the mild clinical course of the disease. Our results indicate that HMGB1 could be a useful prognostic biomarker for disease severity in PUUV and CCHFV infection, where the difference between the mild and severe patients group was highly significant. Even in patients with severe DOBV infection concentrations of HMGB1 were 2.8-times higher than in the mild group, but the difference was not statistically significant. Our results indicated HMGB1 as a potential biomarker for severe hemorrhagic fevers.

Protective roles of pulmonary rehabilitation mixture in experimental pulmonary fibrosis in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Zhang, L.; Ji, Y.X.; Jiang, W.L.; Lv, C.J. [School of Pharmaceutical Sciences, Binzhou Medical University, Yantai (China)

2015-05-08

Abnormal high mobility group protein B1 (HMGB1) activation is involved in the pathogenesis of pulmonary fibrosis. Pulmonary rehabilitation mixture (PRM), which combines extracts from eight traditional Chinese medicines, has very good lung protection in clinical use. However, it is not known if PRM has anti-fibrotic activity. In this study, we investigated the effects of PRM on transforming growth factor-β1 (TGF-β1)-mediated and bleomycin (BLM)-induced pulmonary fibrosis in vitro and in vivo. The effects of PRM on TGF-β1-mediated epithelial-mesenchymal transition (EMT) in A549 cells, on the proliferation of human lung fibroblasts (HLF-1) in vitro, and on BLM-induced pulmonary fibrosis in vivo were investigated. PRM treatment resulted in a reduction of EMT in A549 cells that was associated with attenuating an increase of vimentin and a decrease of E-cadherin. PRM inhibited the proliferation of HLF-1 at an IC{sub 50} of 0.51 µg/mL. PRM ameliorated BLM-induced pulmonary fibrosis in rats, with reduction of histopathological scores and collagen deposition, and a decrease in α-smooth muscle actin (α-SMA) and HMGB1 expression. An increase in receptor for advanced glycation end-product (RAGE) expression was found in BLM-instilled lungs. PRM significantly decreased EMT and prevented pulmonary fibrosis through decreasing HMGB1 and regulating RAGE in vitro and in vivo. PRM inhibited TGF-β1-induced EMT via decreased HMGB1 and vimentin and increased RAGE and E-cadherin levels. In summary, PRM prevented experimental pulmonary fibrosis by modulating the HMGB1/RAGE pathway.

Protective roles of pulmonary rehabilitation mixture in experimental pulmonary fibrosis in vitro and in vivo

International Nuclear Information System (INIS)

Zhang, L.; Ji, Y.X.; Jiang, W.L.; Lv, C.J.

2015-01-01

Abnormal high mobility group protein B1 (HMGB1) activation is involved in the pathogenesis of pulmonary fibrosis. Pulmonary rehabilitation mixture (PRM), which combines extracts from eight traditional Chinese medicines, has very good lung protection in clinical use. However, it is not known if PRM has anti-fibrotic activity. In this study, we investigated the effects of PRM on transforming growth factor-β1 (TGF-β1)-mediated and bleomycin (BLM)-induced pulmonary fibrosis in vitro and in vivo. The effects of PRM on TGF-β1-mediated epithelial-mesenchymal transition (EMT) in A549 cells, on the proliferation of human lung fibroblasts (HLF-1) in vitro, and on BLM-induced pulmonary fibrosis in vivo were investigated. PRM treatment resulted in a reduction of EMT in A549 cells that was associated with attenuating an increase of vimentin and a decrease of E-cadherin. PRM inhibited the proliferation of HLF-1 at an IC 50 of 0.51 µg/mL. PRM ameliorated BLM-induced pulmonary fibrosis in rats, with reduction of histopathological scores and collagen deposition, and a decrease in α-smooth muscle actin (α-SMA) and HMGB1 expression. An increase in receptor for advanced glycation end-product (RAGE) expression was found in BLM-instilled lungs. PRM significantly decreased EMT and prevented pulmonary fibrosis through decreasing HMGB1 and regulating RAGE in vitro and in vivo. PRM inhibited TGF-β1-induced EMT via decreased HMGB1 and vimentin and increased RAGE and E-cadherin levels. In summary, PRM prevented experimental pulmonary fibrosis by modulating the HMGB1/RAGE pathway

HMGB1-mediated DNA bending: Distinct roles in increasing p53 binding to DNA and the transactivation of p53-responsive gene promoters.

Science.gov (United States)

Štros, Michal; Kučírek, Martin; Sani, Soodabeh Abbasi; Polanská, Eva

2018-03-01

HMGB1 is a chromatin-associated protein that has been implicated in many important biological processes such as transcription, recombination, DNA repair, and genome stability. These functions include the enhancement of binding of a number of transcription factors, including the tumor suppressor protein p53, to their specific DNA-binding sites. HMGB1 is composed of two highly conserved HMG boxes, linked to an intrinsically disordered acidic C-terminal tail. Previous reports have suggested that the ability of HMGB1 to bend DNA may explain the in vitro HMGB1-mediated increase in sequence-specific DNA binding by p53. The aim of this study was to reinvestigate the importance of HMGB1-induced DNA bending in relationship to the ability of the protein to promote the specific binding of p53 to short DNA duplexes in vitro, and to transactivate two major p53-regulated human genes: Mdm2 and p21/WAF1. Using a number of HMGB1 mutants, we report that the HMGB1-mediated increase in sequence-specific p53 binding to DNA duplexes in vitro depends very little on HMGB1-mediated DNA bending. The presence of the acidic C-terminal tail of HMGB1 and/or the oxidation of the protein can reduce the HMGB1-mediated p53 binding. Interestingly, the induction of transactivation of p53-responsive gene promoters by HMGB1 requires both the ability of the protein to bend DNA and the acidic C-terminal tail, and is promoter-specific. We propose that the efficient transactivation of p53-responsive gene promoters by HMGB1 depends on complex events, rather than solely on the promotion of p53 binding to its DNA cognate sites. Copyright © 2018 Elsevier B.V. All rights reserved.

The S100P/RAGE signaling pathway regulates expression of microRNA-21 in colon cancer cells.

Science.gov (United States)

Mercado-Pimentel, Melania E; Onyeagucha, Benjamin C; Li, Qing; Pimentel, Angel C; Jandova, Jana; Nelson, Mark A

2015-08-19

S100P signaling through the receptor for advanced glycation end-products (RAGE) contributes to colon cancer invasion and metastasis, but the mechanistic features of this process are obscure. Here, we investigate whether activation of S100P/RAGE signaling regulates oncogenic microRNA-21 (miR-21). We show that exogenous S100P up-regulates miR-21 levels in human colon cancer cells, whereas knockdown of S100P results in a decrease of miR-21. Furthermore, blockage of RAGE with anti-RAGE antibody suppresses S100P induction of miR-21. In addition, we found that S100P induction of miR-21 expression involves ERK and is suppressed by the MEK inhibitor U0126. Also, S100P treatment stimulates the enrichment of c-Fos, and AP-1 family members, at the miR-21 gene promoter. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Effects of propofol on lipopolysaccharide-induced expression and release of HMGB1 in macrophages

Energy Technology Data Exchange (ETDEWEB)

Wang, T.; Wei, X.Y.; Liu, B.; Wang, L.J.; Jiang, L.H. [Department of Anesthesiology, the Third Affiliated Hospital, Zhengzhou University, Zhengzhou (China)

2015-02-24

This study aimed to determine the effects of different concentrations of propofol (2,6-diisopropylphenol) on lipopolysaccharide (LPS)-induced expression and release of high-mobility group box 1 protein (HMGB1) in mouse macrophages. Mouse macrophage cell line RAW264.7 cells were randomly divided into 5 treatment groups. Expression levels of HMGB1 mRNA were detected using RT-PCR, and cell culture supernatant HMGB1 protein levels were detected using enzyme-linked immunosorbent assay (ELISA). Translocation of HMGB1 from the nucleus to the cytoplasm in macrophages was observed by Western blotting and activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the nucleus was detected using ELISA. HMGB1 mRNA expression levels increased significantly in the cell culture supernatant and in cells after 24 h of stimulating RAW264.7 cells with LPS (500 ng/mL). However, HMGB1 mRNA expression levels in the P2 and P3 groups, which received 500 ng/mL LPS with 25 or 50 μmol/mL propofol, respectively, were significantly lower than those in the group receiving LPS stimulation (P<0.05). After stimulation by LPS, HMGB1 protein levels were reduced significantly in the nucleus but were increased in the cytoplasm (P<0.05). Simultaneously, the activity of NF-κB was enhanced significantly (P<0.05). After propofol intervention, HMGB1 translocation from the nucleus to the cytoplasm and NF-κB activity were inhibited significantly (each P<0.05). Thus, propofol can inhibit the LPS-induced expression and release of HMGB1 by inhibiting HMGB1 translocation and NF-κB activity in RAW264.7 cells, suggesting propofol may be protective in patients with sepsis.

Disulfide high mobility group box-1 causes bladder pain through bladder Toll-like receptor 4.

Science.gov (United States)

Ma, Fei; Kouzoukas, Dimitrios E; Meyer-Siegler, Katherine L; Westlund, Karin N; Hunt, David E; Vera, Pedro L

2017-05-25

Bladder pain is a prominent symptom in several urological conditions (e.g. infection, painful bladder syndrome/interstitial cystitis, cancer). Understanding the mechanism of bladder pain is important, particularly when the pain is not accompanied by bladder pathology. Stimulation of protease activated receptor 4 (PAR4) in the urothelium results in bladder pain through release of urothelial high mobility group box-1 (HMGB1). HGMB1 has two functionally active redox states (disulfide and all-thiol) and it is not known which form elicits bladder pain. Therefore, we investigated whether intravesical administration of specific HMGB1 redox forms caused abdominal mechanical hypersensitivity, micturition changes, and bladder inflammation in female C57BL/6 mice 24 hours post-administration. Moreover, we determined which of the specific HMGB1 receptors, Toll-like receptor 4 (TLR4) or receptor for advanced glycation end products (RAGE), mediate HMGB1-induced changes. Disulfide HMGB1 elicited abdominal mechanical hypersensitivity 24 hours after intravesical (5, 10, 20 μg/150 μl) instillation. In contrast, all-thiol HMGB1 did not produce abdominal mechanical hypersensitivity in any of the doses tested (1, 2, 5, 10, 20 μg/150 μl). Both HMGB1 redox forms caused micturition changes only at the highest dose tested (20 μg/150 μl) while eliciting mild bladder edema and reactive changes at all doses. We subsequently tested whether the effects of intravesical disulfide HMGB1 (10 μg/150 μl; a dose that did not produce inflammation) were prevented by systemic (i.p.) or local (intravesical) administration of either a TLR4 antagonist (TAK-242) or a RAGE antagonist (FPS-ZM1). Systemic administration of either TAK-242 (3 mg/kg) or FPS-ZM1 (10 mg/kg) prevented HMGB1 induced abdominal mechanical hypersensitivity while only intravesical TLR4 antagonist pretreatment (1.5 mg/ml; not RAGE) had this effect. The disulfide form of HMGB1 mediates bladder pain directly (not

HMGB1 is an independent predictor of death and heart transplantation in heart failure.

Science.gov (United States)

Volz, H C; Laohachewin, D; Schellberg, D; Wienbrandt, A R; Nelles, M; Zugck, C; Kaya, Z; Katus, H A; Andrassy, M

2012-06-01

High-Mobility-Group Box 1 (HMGB1) has been established as an important mediator of myocardial inflammation and associated with progression of heart failure (HF). The aim of this study was to analyze the prognostic value of systemic HMGB1 levels in HF patients with ischemic and non-ischemic cardiomyopathy. We conducted an analysis (median follow-up time 2.5 years) of HMGB1 plasma concentration in 154 patients with systolic HF and correlated the results with disease severity and prognosis. HMGB1 in HF patients with severe symptoms (NYHA III/IV; 5.35 ng/ml; interquartile range (IQR) = 3.48-8.42 ng/ml) was significantly elevated compared with that in patients with mild symptoms (NYHA I/II; 3.37 ng/ml, IQR = 2.31-5.22 ng/ml, p < 0.0001) and with controls (3.25 ng/ml, IQR = 3.04-3.67 ng/ml, p < 0.0001). HMGB1 levels correlated with other markers of heart failure indicating an association of HMGB1 with disease severity in HF. In a univariate cox regression model for the combined endpoint of death and heart transplantation, HMGB1 proved to be a predictor at cut-off values based on HMGB1 terciles of either 3.4 or 6.1 ng/ml (p = 0.001 and p < 0.0001, respectively). In a multivariate cox regression model, which included NT-proBNP, creatinine, age, NYHA class, white blood cell count, anemia, and age, HMGB1 remained an independent predictor of the combined endpoint (hazard ratio (HR) = 2.48, 95% confidence interval (CI) = 1.06-5.83, p = 0.037 and HR = 2.48, 95% CI = 1.31-4.71, p = 0.005, respectively). Our findings demonstrate that HMGB1 plasma concentration is elevated in HF and correlates with disease severity and that is an independent predictor of the combined endpoint death and heart transplantation in HF patients.

The effects of lead exposure on the expression of HMGB1 and HO-1 in rats and PC12 cells.

Science.gov (United States)

Yang, Meiyuan; Li, Yaobin; Wang, Ying; Cheng, Nuo; Zhang, Yi; Pang, Shimin; Shen, Qiwei; Zhao, Lijuan; Li, Guilin; Zhu, Gaochun

2018-05-15

Lead (Pb) is an environmental neurotoxic metal. Chronic exposure to Pb causes deficits of learning and memory in children and spatial learning deficits in developing rats. In this study we investigated the effects of Pb exposure on the expression of HMGB1 and HO-1 in rats and PC12 cells. The animals were randomly divided to three groups: control group; low lead exposure group; high lead exposure group; PC12 cells were divided into 3 groups: 0 μM (control group), 1 μM and 100 μM Pb acetate. The results showed that Pb levels in blood and brain of Pb exposed groups were significantly higher than that of the control group (p < 0.05). The expression of HMGB1 and HO-1 were increased in Pb exposed groups than that of the control group (p < 0.05). Moreover, we found that the up-regulation of HO-1 in Pb exposure environment inhibited the expression of HMGB1. Copyright © 2018 Elsevier B.V. All rights reserved.

HMGB1 mediates endogenous TLR2 activation and brain tumor regression.

Directory of Open Access Journals (Sweden)

James F Curtin

2009-01-01

Full Text Available Glioblastoma multiforme (GBM is the most aggressive primary brain tumor that carries a 5-y survival rate of 5%. Attempts at eliciting a clinically relevant anti-GBM immune response in brain tumor patients have met with limited success, which is due to brain immune privilege, tumor immune evasion, and a paucity of dendritic cells (DCs within the central nervous system. Herein we uncovered a novel pathway for the activation of an effective anti-GBM immune response mediated by high-mobility-group box 1 (HMGB1, an alarmin protein released from dying tumor cells, which acts as an endogenous ligand for Toll-like receptor 2 (TLR2 signaling on bone marrow-derived GBM-infiltrating DCs.Using a combined immunotherapy/conditional cytotoxic approach that utilizes adenoviral vectors (Ad expressing Fms-like tyrosine kinase 3 ligand (Flt3L and thymidine kinase (TK delivered into the tumor mass, we demonstrated that CD4(+ and CD8(+ T cells were required for tumor regression and immunological memory. Increased numbers of bone marrow-derived, tumor-infiltrating myeloid DCs (mDCs were observed in response to the therapy. Infiltration of mDCs into the GBM, clonal expansion of antitumor T cells, and induction of an effective anti-GBM immune response were TLR2 dependent. We then proceeded to identify the endogenous ligand responsible for TLR2 signaling on tumor-infiltrating mDCs. We demonstrated that HMGB1 was released from dying tumor cells, in response to Ad-TK (+ gancyclovir [GCV] treatment. Increased levels of HMGB1 were also detected in the serum of tumor-bearing Ad-Flt3L/Ad-TK (+GCV-treated mice. Specific activation of TLR2 signaling was induced by supernatants from Ad-TK (+GCV-treated GBM cells; this activation was blocked by glycyrrhizin (a specific HMGB1 inhibitor or with antibodies to HMGB1. HMGB1 was also released from melanoma, small cell lung carcinoma, and glioma cells treated with radiation or temozolomide. Administration of either glycyrrhizin or anti-HMGB

HMGB1 in vascular diseases : Its role in vascular inflammation and atherosclerosis

NARCIS (Netherlands)

de Souza, A. W. S.; Westra, J.; Limburg, P. C.; Bijl, M.; Kallenberg, C. G. M.

2012-01-01

The nuclear protein high mobility group box 1 (HMGB1) has been suggested to be involved in the pathogenesis of several vascular diseases such as systemic vasculitis and atherosclerosis. In systemic vasculitides including ANCA-associated vasculitis and Kawasaki disease, serum HMGB1 levels are higher

The dengue vector Aedes aegypti contains a functional high mobility group box 1 (HMGB1 protein with a unique regulatory C-terminus.

Directory of Open Access Journals (Sweden)

Fabio Schneider Ribeiro

Full Text Available The mosquito Aedes aegypti can spread the dengue, chikungunya and yellow fever viruses. Thus, the search for key molecules involved in the mosquito survival represents today a promising vector control strategy. High Mobility Group Box (HMGB proteins are essential nuclear factors that maintain the high-order structure of chromatin, keeping eukaryotic cells viable. Outside the nucleus, secreted HMGB proteins could alert the innate immune system to foreign antigens and trigger the initiation of host defenses. In this work, we cloned and functionally characterized the HMGB1 protein from Aedes aegypti (AaHMGB1. The AaHMGB1 protein typically consists of two HMG-box DNA binding domains and an acidic C-terminus. Interestingly, AaHMGB1 contains a unique alanine/glutamine-rich (AQ-rich C-terminal region that seems to be exclusive of dipteran HMGB proteins. AaHMGB1 is localized to the cell nucleus, mainly associated with heterochromatin. Circular dichroism analyses of AaHMGB1 or the C-terminal truncated proteins revealed α-helical structures. We showed that AaHMGB1 can effectively bind and change the topology of DNA, and that the AQ-rich and the C-terminal acidic regions can modulate its ability to promote DNA supercoiling, as well as its preference to bind supercoiled DNA. AaHMGB1 is phosphorylated by PKA and PKC, but not by CK2. Importantly, phosphorylation of AaHMGB1 by PKA or PKC completely abolishes its DNA bending activity. Thus, our study shows that a functional HMGB1 protein occurs in Aedes aegypt and we provide the first description of a HMGB1 protein containing an AQ-rich regulatory C-terminus.

High Expression of High-Mobility Group Box 1 in Menstrual Blood: Implications for Endometriosis.

Science.gov (United States)

Shimizu, Keiko; Kamada, Yasuhiko; Sakamoto, Ai; Matsuda, Miwa; Nakatsuka, Mikiya; Hiramatsu, Yuji

2017-11-01

Endometriosis is a benign gynecologic disease characterized by the presence of ectopic endometrium and associated with inflammation and immune abnormalities. However, the molecular basis for endometriosis is not well understood. To address this issue, the present study examined the expression of high-mobility group box (HMGB) 1 in menstrual blood to investigate its role in the ectopic growth of human endometriotic stromal cells (ESCs). A total of 139 patients were enrolled in this study; 84 had endometriosis and 55 were nonendometriotic gynecological patients (control). The HMGB1 levels in various fluids were measured by enzyme-linked immunosorbent assay. Expression of receptor for advanced glycation end products (RAGE) in eutopic and ectopic endometrium was assessed by immunohistochemistry, and RAGE and vascular endothelial growth factor ( VEGF) messenger RNA expression in HMGB1- and lipopolysaccharide (LPS)-treated ESCs was evaluated by real-time polymerase chain reaction. The HMGB1 concentration was higher in menstrual blood than in serum or peritoneal fluid ( P endometriosis following retrograde menstruation when complexed with other factors such as LPS by inducing inflammation and angiogenesis.

Receptor for advanced glycation endproducts (RAGE maintains pulmonary structure and regulates the response to cigarette smoke.

Directory of Open Access Journals (Sweden)

Lisa Wolf

Full Text Available The receptor for advanced glycation endproducts (RAGE is highly expressed in the lung but its physiological functions in this organ is still not completely understood. To determine the contribution of RAGE to physiological functions of the lung, we analyzed pulmonary mechanics and structure of wildtype and RAGE deficient (RAGE-/- mice. RAGE deficiency spontaneously resulted in a loss of lung structure shown by an increased mean chord length, increased respiratory system compliance, decreased respiratory system elastance and increased concentrations of serum protein albumin in bronchoalveolar lavage fluids. Pulmonary expression of RAGE was mainly localized on alveolar epithelial cells and alveolar macrophages. Primary murine alveolar epithelial cells isolated from RAGE-/- mice revealed an altered differentiation and defective barrier formation under in vitro conditions. Stimulation of interferone-y (IFNy-activated alveolar macrophages deficient for RAGE with Toll-like receptor (TLR ligands resulted in significantly decreased release of proinflammatory cytokines and chemokines. Exposure to chronic cigarette smoke did not affect emphysema-like changes in lung parenchyma in RAGE-/- mice. Acute cigarette smoke exposure revealed a modified inflammatory response in RAGE-/- mice that was characterized by an influx of macrophages and a decreased keratinocyte-derived chemokine (KC release. Our data suggest that RAGE regulates the differentiation of alveolar epithelial cells and impacts on the development and maintenance of pulmonary structure. In cigarette smoke-induced lung pathology, RAGE mediates inflammation that contributes to lung damage.

RAGE-dependent activation of gene expression of superoxide dismutase and vanins by AGE-rich extracts in mice cardiac tissue and murine cardiac fibroblasts.

Science.gov (United States)

Leuner, Beatrice; Ruhs, Stefanie; Brömme, Hans-Jürgen; Bierhaus, Angelika; Sel, Saadettin; Silber, Rolf-Edgar; Somoza, Veronika; Simm, Andreas; Nass, Norbert

2012-10-01

Advanced glycation end products (AGEs) are stable compounds formed from initial Maillard reaction products. They are considered as markers for ageing and often associated with age-related, degenerative diseases. Bread crust represents an established model for nutritional compounds rich in AGEs and is able to induce antioxidative defense genes such as superoxide dismutases and vanins in cardiac cells. The aim of this study was to investigate to what extend the receptor for AGEs (RAGE) contributes to this response. Signal transduction in response to bread crust extract was analysed in cardiac fibroblasts derived from C57/B6-NCrl (RAGE +/+) and the corresponding RAGE-knock out C57/B6-NCrl mouse strain (RAGE -/-). Activation of superoxide dismutases in animals was then analysed upon bread crust feeding in these two mice strains. Cardiac fibroblasts from RAGE -/- mice did not express RAGE, but the expression of AGER-1 and AGER-3 was up-regulated, whereas the expression of SR-B1 was down-regulated. RAGE -/- cells were less sensitive to BCE in terms of MAP-kinase phosphorylation and NF-κB reporter gene activation. Bread crust extract induced mRNA levels of MnSOD and Vnn-1 were also reduced in RAGE -/- cells, whereas Vnn-3 mRNA accumulation seemed to be RAGE receptor independent. In bread crust feeding experiments, RAGE -/- mice did not exhibit an activation of MnSOD-mRNA and -protein accumulation as observed for the RAGE +/+ animals. In conclusion, RAGE was clearly a major factor for the induction of antioxidant defense signals derived from bread crust in cardiac fibroblast and mice. Nevertheless higher doses of bread crust extract could overcome the RAGE dependency in cell cultures, indicating that additional mechanisms are involved in BCE-mediated activation of SOD and vanin expression.

Molecular basis for the redox control of nuclear transport of the structural chromatin protein Hmgb1

International Nuclear Information System (INIS)

Hoppe, George; Talcott, Katherine E.; Bhattacharya, Sanjoy K.; Crabb, John W.; Sears, Jonathan E.

2006-01-01

Oxidative stress can induce a covalent disulfide bond between protein and peptide thiols that is reversible through enzymatic catalysis. This process provides a post-translational mechanism for control of protein function and may also protect thiol groups from irreversible oxidation. High mobility group protein B1 (Hmgb1), a DNA-binding structural chromosomal protein and transcriptional co-activator was identified as a substrate of glutaredoxin. Hmgb1 contains 3 cysteines, Cys23, 45, and 106. In mild oxidative conditions, Cys23 and Cys45 readily form an intramolecular disulfide bridge, whereas Cys106 remains in the reduced form. The disulfide bond between Cys23 and Cys45 is a target of glutathione-dependent reduction by glutaredoxin. Endogenous Hmgb1 as well as GFP-tagged wild-type Hmgb1 co-localize in the nucleus of CHO cells. While replacement of Hmgb1 Cys23 and/or 45 with serines did not affect the nuclear distribution of the mutant proteins, Cys106-to-Ser and triple cysteine mutations impaired nuclear localization of Hmgb1. Our cysteine targeted mutational analysis suggests that Cys23 and 45 induce conformational changes in response to oxidative stress, whereas Cys106 appears to be critical for the nucleocytoplasmic shuttling of Hmgb1

High mobility group box 1 levels are not associated with subclinical carotid atherosclerosis in patients with granulomatosis with polyangiitis but are reduced by glucocorticoids and statins

NARCIS (Netherlands)

Silva de Souza, Alexandre; De Leeuw, Karina; Westra, Johanna; Smit, Andries J.; Van Der Graaf, Anne Marijn; Nienhuis, Hans L.A.; Bijzet, Johan; Limburg, Pieter C.; Stegeman, Coen A.; Bijl, Marc; Kallenberg, Cees G.M.

2012-01-01

Background/Purpose: High mobility group box 1 (HMGB1) is a non-histone DNA binding protein that is passively released by dying cells or actively secreted by immunocompetent cells and the receptor for advanced glycation end-products (RAGE) is one of its receptors. Higher levels of HMGB1 have been

Antiseptic effect of vicenin-2 and scolymoside from Cyclopia subternata (honeybush) in response to HMGB1 as a late sepsis mediator in vitro and in vivo.

Science.gov (United States)

Lee, Wonhwa; Yoon, Eun-Kyung; Kim, Kyung-Min; Park, Dong Ho; Bae, Jong-Sup

2015-08-01

Cyclopia subternata is a medicinal plant commonly used in traditional medicine to relieve pain. In this study, we investigated the antiseptic effects and underlying mechanisms of vicenin-2 and scolymoside, which are 2 active compounds from C. subternata that act against high mobility group box 1 (HMGB1)-mediated septic responses in human umbilical vein endothelial cells (HUVECs) and mice. The antiseptic activities of vicenin-2 and scolymoside were determined by measuring permeability, neutrophil adhesion and migration, and activation of proinflammatory proteins in HMGB1-activated HUVECs and mice. According to the results, vicenin-2 and scolymoside effectively inhibited lipopolysaccharide-induced release of HMGB1, and suppressed HMGB1-mediated septic responses such as hyperpermeability, the adhesion and migration of leukocytes, and the expression of cell adhesion molecules. In addition, vicenin-2 and scolymoside suppressed the production of tumor necrosis factor-α and interleukin 6, and activation of nuclear factor-κB and extracellular regulated kinases 1/2 by HMGB1. Collectively, these results indicate that vicenin-2 and scolymoside could be a potential therapeutic agents for the treatment of various severe vascular inflammatory diseases via inhibition of the HMGB1 signaling pathway.

Inhibition of HMGB1 Translocation by Green Tea Extract in Rats Exposed to Environmental Tobacco Smoke

Directory of Open Access Journals (Sweden)

Sirintip Chaichalotornkul

2012-01-01

Full Text Available Environmental tobacco smoke (ETS exposure is linked to carcinogenic, oxidative and inflammatory cellular reactions. Green tea polyphenol reportedly plays a role in the prevention of inflammation-related diseases. To evaluate the effects of green tea extract (GTE on cellular location of High Mobility Group Box-1 (HMGB1 protein, we studied the lung tissue in rats exposed to cigarette smoke (CS. Rats were divided into three groups; CS, CSG, and C, which were groups of CS-treated only, CS-treated with GTE dietary supplement, and the control, respectively. Our findings by immunocytochemistry showed that abundant HMGB1 translocated from the nucleus to the cytoplasm in the lung tissues of rats that were exposed to CS, whereas HMGB1 was localized to the nuclei of CSG and C group. For in vitro studies, cotinine stimulated the secretion of HMGB1 in a dose and time dependent manner and the HMGB1 level was suppressed by GTE in murine macrophage cell lines. Our results could suggest that GTE supplementation which could suppress HMGB1 may offer a beneficial effect against diseases.

RAGE splicing variants in mammals.

Science.gov (United States)

Sterenczak, Katharina Anna; Nolte, Ingo; Murua Escobar, Hugo

2013-01-01

The receptor for advanced glycation end products (RAGE) is a multiligand receptor of environmental stressors which plays key roles in pathophysiological processes, including immune/inflammatory disorders, Alzheimer's disease, diabetic arteriosclerosis, tumorigenesis, and metastasis. Besides the full-length RAGE protein in humans nearly 20 natural occurring RAGE splicing variants were described on mRNA and protein level. These naturally occurring isoforms are characterized by either N-terminally or C-terminally truncations and are discussed as possible regulators of the full-length RAGE receptor either by competitive ligand binding or by displacing the full-length protein in the membrane. Accordingly, expression deregulations of the naturally occurring isoforms were supposed to have significant effect on RAGE-mediated disorders. Thereby the soluble C-truncated RAGE isoforms present in plasma and tissues are the mostly focused isoforms in research and clinics. Deregulations of the circulating levels of soluble RAGE forms were reported in several RAGE-associated pathological disorders including for example atherosclerosis, diabetes, renal failure, Alzheimer's disease, and several cancer types. Regarding other mammalian species, the canine RAGE gene showed high similarities to the corresponding human structures indicating RAGE to be evolutionary highly conserved between both species. Similar to humans the canine RAGE showed a complex and extensive splicing activity leading to a manifold pattern of RAGE isoforms. Due to the similarities seen in several canine and human diseases-including cancer-comparative structural and functional analyses allow the development of RAGE and ligand-specific therapeutic approaches beneficial for human and veterinary medicine.

Soluble Receptor for Advanced Glycation End Product Ameliorates Chronic Intermittent Hypoxia Induced Renal Injury, Inflammation, and Apoptosis via P38/JNK Signaling Pathways

Directory of Open Access Journals (Sweden)

Xu Wu

2016-01-01

Full Text Available Obstructive sleep apnea (OSA associated chronic kidney disease is mainly caused by chronic intermittent hypoxia (CIH triggered tissue damage. Receptor for advanced glycation end product (RAGE and its ligand high mobility group box 1 (HMGB1 are expressed on renal cells and mediate inflammatory responses in OSA-related diseases. To determine their roles in CIH-induced renal injury, soluble RAGE (sRAGE, the RAGE neutralizing antibody, was intravenously administered in a CIH model. We also evaluated the effect of sRAGE on inflammation and apoptosis. Rats were divided into four groups: (1 normal air (NA, (2 CIH, (3 CIH+sRAGE, and (4 NA+sRAGE. Our results showed that CIH accelerated renal histological injury and upregulated RAGE-HMGB1 levels involving inflammatory (NF-κB, TNF-α, and IL-6, apoptotic (Bcl-2/Bax, and mitogen-activated protein kinases (phosphorylation of P38, ERK, and JNK signal transduction pathways, which were abolished by sRAGE but p-ERK. Furthermore, sRAGE ameliorated renal dysfunction by attenuating tubular endothelial apoptosis determined by immunofluorescence staining of CD31 and TUNEL. These findings suggested that RAGE-HMGB1 activated chronic inflammatory transduction cascades that contributed to the pathogenesis of the CIH-induced renal injury. Inhibition of RAGE ligand interaction by sRAGE provided a therapeutic potential for CIH-induced renal injury, inflammation, and apoptosis through P38 and JNK pathways.

In vivo relative quantitative proteomics reveals HMGB1 as a downstream mediator of oestrogen-stimulated keratinocyte migration.

Science.gov (United States)

Shin, Jung U; Noh, Ji Yeon; Lee, Ju Hee; Lee, Won Jai; Yoo, Jong Shin; Kim, Jin Young; Kim, Hyeran; Jung, Inhee; Jin, Shan; Lee, Kwang Hoon

2015-06-01

It is known that oestrogen influences skin wound healing by modulating the inflammatory response, cytokine expression and extracellular matrix deposition; accelerating re-epithelialization; and stimulating angiogenesis. To identify novel proteins associated with effects of oestrogen on keratinocyte, stable isotope labelling by amino acids in cell culture (SILAC)-based mass spectrometry was performed. Using SILAC, quantification of 1085 proteins was achieved. Among these proteins, 60 proteins were upregulated and 32 proteins were downregulated. Among significantly upregulated proteins, high-mobility group protein B1 (HMGB1) has been further evaluated for its role in the effect of oestrogen on keratinocytes. HMGB1 expression was strongly induced in oestrogen-treated keratinocytes in dose- and time-dependent manner. Further, HMGB1 was able to significantly accelerate the rate of HaCaT cell migration. To determine whether HMGB1 is involved in E2-induced HaCaT cell migration, cells were transfected with HMGB1 siRNA. Knockdown of HMGB1 blocked oestrogen-induced keratinocyte migration. Collectively, these experiments demonstrate that HMGB1 is a novel downstream mediator of oestrogen-stimulated keratinocyte migration. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Real-time Kinetics of High-mobility Group Box 1 (HMGB1) Oxidation in Extracellular Fluids Studied by in Situ Protein NMR Spectroscopy*

Science.gov (United States)

Zandarashvili, Levani; Sahu, Debashish; Lee, Kwanbok; Lee, Yong Sun; Singh, Pomila; Rajarathnam, Krishna; Iwahara, Junji

2013-01-01

Some extracellular proteins are initially secreted in reduced forms via a non-canonical pathway bypassing the endoplasmic reticulum and become oxidized in the extracellular space. One such protein is HMGB1 (high-mobility group box 1). Extracellular HMGB1 has different redox states that play distinct roles in inflammation. Using a unique NMR-based approach, we have investigated the kinetics of HMGB1 oxidation and the half-lives of all-thiol and disulfide HMGB1 species in serum, saliva, and cell culture medium. In this approach, salt-free lyophilized 15N-labeled all-thiol HMGB1 was dissolved in actual extracellular fluids, and the oxidation and clearance kinetics were monitored in situ by recording a series of heteronuclear 1H-15N correlation spectra. We found that the half-life depends significantly on the extracellular environment. For example, the half-life of all-thiol HMGB1 ranged from ∼17 min (in human serum and saliva) to 3 h (in prostate cancer cell culture medium). Furthermore, the binding of ligands (glycyrrhizin and heparin) to HMGB1 significantly modulated the oxidation kinetics. Thus, the balance between the roles of all-thiol and disulfide HMGB1 proteins depends significantly on the extracellular environment and can also be artificially modulated by ligands. This is important because extracellular HMGB1 has been suggested as a therapeutic target for inflammatory diseases and cancer. Our work demonstrates that the in situ protein NMR approach is powerful for investigating the behavior of proteins in actual extracellular fluids containing an enormous number of different molecules. PMID:23447529

Proinflammatory Effect of High Glucose Concentrations on HMrSV5 Cells via the Autocrine Effect of HMGB1

Directory of Open Access Journals (Sweden)

Yuening Chu

2017-09-01

Full Text Available Background: Peritoneal fibrosis, in which inflammation and apoptosis play crucial pathogenic roles, is a severe complication associated with the treatment of kidney failure with peritoneal dialysis (PD using a glucose-based dialysate. Mesothelial cells (MCs take part in the inflammatory processes by producing various cytokines and chemokines, such as monocyte chemoattractant protein 1 (MCP-1 and interleukin 8 (IL-8. The apoptosis of MCs induced by high glucose levels also contributes to complications of PD. High mobility group protein B1 (HMGB1 is an inflammatory factor that has repeatedly been proven to be related to the occurrence of peritoneal dysfunction.Aim: In this study, we aimed to explore the effect and underlying mechanism of endogenous HMGB1 in high-glucose-induced MC injury.Methods: The human peritoneal MC line, HMrSV5 was cultured in high-glucose medium and incubated with recombinant HMGB1. Cellular expression of HMGB1 was blocked using HMGB1 small interfering RNA (siRNA. Apoptosis and production of inflammatory factors as well as the potential intermediary signaling pathways were examined.Results: The major findings of these analyses were: (1 MCs secreted HMGB1 from the nucleus during exposure to high glucose levels; HMGB1 acted in an autocrine fashion on the MCs to promote the production of MCP-1 and IL-8; (2 HMGB1 had little effect on high-glucose-induced apoptosis of the MCs; and (3 HMGB1-mediated MCP-1 and IL-8 production depended on the activation of MAPK signaling pathways. In conclusion, endogenous HMGB1 plays an important role in the inflammatory reaction induced by high glucose on MCs via mitogen-activated protein kinase (MAPK signaling pathways, but it seems to have little effect on high-glucose-induced apoptosis.

Soluble Receptor for Advanced Glycation End Products (sRAGE is Up-Regulated in Multiple Sclerosis Patients Treated with Interferon β-1a

Directory of Open Access Journals (Sweden)

Mahnoosh Rahimi

2018-03-01

Full Text Available Background/Aims: Multiple sclerosis (MS is a chronic inflammatory disorder of the central nervous system. Considering the role of immune system in its pathogenesis, researchers have focused on evaluation of the expression of immune-related genes or proteins in MS patients. Among proteins whose participation in inflammatory process has been documented is the receptor for advanced glycation end products (RAGE. Methods: In the present study, we compared RAGE transcript levels by means of quantitative real-time PCR as well as the serum level of soluble RAGE (sRAGE by means of enzyme- linked immunosorbent assay (ELISA in 50 IFNβ-1a responsive relapsing-remitting MS patients when compared with age and sex-matched healthy subjects. Results: Elevated expression of RAGE as well as higher levels of sRAGE were detected in IFN-β responsive MS patients compared with the controls. A significant inverse correlation between sRAGE plasma concentrations and the expanded disability status scale (EDSS was also detected in which each unit of increase in sRAGE level resulted in a 0.308 unit decrease in EDSS. Conclusion: Considering the stable clinical state of the MS patients in this study and their response to IFNβ-1a, the elevated levels of sRAGE in patients compared with healthy subjects could be related to the effects of this kind of treatment.

Discovering Small Molecule Inhibitors Targeted to Ligand-Stimulated RAGE-DIAPH1 Signaling Transduction

Science.gov (United States)

Pan, Jinhong

The receptor of advanced glycation end product (RAGE) is a multiligand receptor of the immunoglobulin superfamily of cell surface molecules, which plays an important role in immune responses. Full-length RAGE includes three extracellular immunoglobulin domains, a transmembrane domain and an intracellular domain. It is a pattern recognition receptor that can bind diverse ligands. NMR spectroscopy and x-ray crystallization studies of the extracellular domains of RAGE indicate that RAGE ligands bind by distinct charge- and hydrophobicity-dependent mechanisms. It is found that calgranulin binding to the C1C2 domain or AGEs binding to the V domain activates extracellular signaling, which triggers interactions of the RAGE cytoplasmic tail (ctRAGE) with intracellular effector, such as diaphanous 1 (DIAPH1), to initiate signal transduction cascades. ctRAGE is essential for RAGE-ligand-mediated signal transduction and consequent modulation of gene expression and cellular properties. RAGE is over-expressed in diseased tissues of most RAGE-associated pathogenic conditions, such as complications of Alzheimer's diseases, diabetes, vascular diseases, inflammation, cancers and neurodegeneration. They are the major diseases affecting a large population worldwide. RAGE can function as a biomarker or drug target for these diseases. The cytoplasmic tail of RAGE can be used as a drug target to inhibit RAGE-induced intracellular signaling by small molecule inhibitors to treat RAGE-associated diseases. We developed a high throughput screening assay with which we probed a small molecule library of 58,000 compounds to find that 777 small molecules displayed 50% inhibition and 97 compounds demonstrated dose-dependent inhibition of the binding of ctRAGE-DIAPH1. Eventually, there were 13 compounds which displayed dose-dependent inhibition of ctRAGE binding to DIAPH1 and direct binding to ctRAGE analyzed by 15N HSQC-NMR and native tryptophan fluorescence titration experiments; thus, they were

Barrier protective effects of withaferin A in HMGB1-induced inflammatory responses in both cellular and animal models

International Nuclear Information System (INIS)

Lee, Wonhwa; Kim, Tae Hoon; Ku, Sae-Kwang; Min, Kyoung-jin; Lee, Hyun-Shik; Kwon, Taeg Kyu; Bae, Jong-Sup

2012-01-01

Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. In this study, we first investigated the possible barrier protective effects of WFA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and in mice induced by high mobility group box 1 protein (HMGB1) and the associated signaling pathways. The barrier protective activities of WFA were determined by measuring permeability, leukocytes adhesion and migration, and activation of pro-inflammatory proteins in HMGB1-activated HUVECs. We found that WFA inhibited lipopolysaccharide (LPS)-induced HMGB1 release and HMGB1-mediated barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of leukocytes to human endothelial cells. WFA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that WFA suppressed the production of interleukin 6, tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by HMGB1. Collectively, these results suggest that WFA protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. -- Highlights: ► Withaferin A inhibited LPS induced HMGB1 release. ► Withaferin A reduced HMGB1-mediated hyperpermeability. ► Withaferin A inhibited HMGB1-mediated adhesion and migration of leukocytes. ► Withaferin A inhibited HMGB1-mediated activation of NF-κB, IL-6 and TNF-α.

Barrier protective effects of withaferin A in HMGB1-induced inflammatory responses in both cellular and animal models

Energy Technology Data Exchange (ETDEWEB)

Lee, Wonhwa [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University (Korea, Republic of); Kim, Tae Hoon [Department of Herbal Medicinal Pharmacology, Daegu Haany University (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Oriental Medicine, Daegu Haany University, Gyeongsan 712-715 (Korea, Republic of); Min, Kyoung-jin [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Lee, Hyun-Shik [School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Taeg Kyu [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2012-07-01

Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. In this study, we first investigated the possible barrier protective effects of WFA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and in mice induced by high mobility group box 1 protein (HMGB1) and the associated signaling pathways. The barrier protective activities of WFA were determined by measuring permeability, leukocytes adhesion and migration, and activation of pro-inflammatory proteins in HMGB1-activated HUVECs. We found that WFA inhibited lipopolysaccharide (LPS)-induced HMGB1 release and HMGB1-mediated barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of leukocytes to human endothelial cells. WFA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that WFA suppressed the production of interleukin 6, tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by HMGB1. Collectively, these results suggest that WFA protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. -- Highlights: ► Withaferin A inhibited LPS induced HMGB1 release. ► Withaferin A reduced HMGB1-mediated hyperpermeability. ► Withaferin A inhibited HMGB1-mediated adhesion and migration of leukocytes. ► Withaferin A inhibited HMGB1-mediated activation of NF-κB, IL-6 and TNF-α.

HMGB1 a-Box Reverses Brain Edema and Deterioration of Neurological Function in a Traumatic Brain Injury Mouse Model

Directory of Open Access Journals (Sweden)

Lijun Yang

2018-05-01

Full Text Available Background/Aims: Traumatic brain injury (TBI is a complex neurological injury in young adults lacking effective treatment. Emerging evidences suggest that inflammation contributes to the secondary brain injury following TBI, including breakdown of the blood brain barrier (BBB, subsequent edema and neurological deterioration. High mobility group box-1 (HMGB1 has been identified as a key cytokine in the inflammation reaction following TBI. Here, we investigated the therapeutic efficacy of HMGB1 A-box fragment, an antagonist competing with full-length HMGB1 for receptor binding, against TBI. Methods: TBI was induced by controlled cortical impact (CCI in adult male mice. HMGB1 A-box fragment was given intravenously at 2 mg/kg/day for 3 days after CCI. HMGB1 A-box-treated CCI mice were compared with saline-treated CCI mice and sham mice in terms of BBB disruption evaluated by Evan’s blue extravasation, brain edema by brain water content, cell death by propidium iodide staining, inflammation by Western blot and ELISA assay for cytokine productions, as well as neurological functions by the modified Neurological Severity Score, wire grip and beam walking tests. Results: HMGB1 A-box reversed brain damages in the mice following TBI. It significantly reduced brain edema by protecting integrity of the BBB, ameliorated cell degeneration, and decreased expression of pro-inflammatory cytokines released in injured brain after TBI. These cellular and molecular effects were accompanied by improved behavioral performance in TBI mice. Notably, HMGB1 A-box blocked IL-1β-induced HMGB1 release, and preferentially attenuated TLR4, Myd88 and P65 in astrocyte cultures. Conclusion: Our data suggest that HMGB1 is involved in CCI-induced TBI, which can be inhibited by HMGB1 A-box fragment. Therefore, HMGB1 A-box fragment may have therapeutic potential for the secondary brain damages in TBI.

HMGB1 a-Box Reverses Brain Edema and Deterioration of Neurological Function in a Traumatic Brain Injury Mouse Model.

Science.gov (United States)

Yang, Lijun; Wang, Feng; Yang, Liang; Yuan, Yunchao; Chen, Yan; Zhang, Gengshen; Fan, Zhenzeng

2018-01-01

Traumatic brain injury (TBI) is a complex neurological injury in young adults lacking effective treatment. Emerging evidences suggest that inflammation contributes to the secondary brain injury following TBI, including breakdown of the blood brain barrier (BBB), subsequent edema and neurological deterioration. High mobility group box-1 (HMGB1) has been identified as a key cytokine in the inflammation reaction following TBI. Here, we investigated the therapeutic efficacy of HMGB1 A-box fragment, an antagonist competing with full-length HMGB1 for receptor binding, against TBI. TBI was induced by controlled cortical impact (CCI) in adult male mice. HMGB1 A-box fragment was given intravenously at 2 mg/kg/day for 3 days after CCI. HMGB1 A-box-treated CCI mice were compared with saline-treated CCI mice and sham mice in terms of BBB disruption evaluated by Evan's blue extravasation, brain edema by brain water content, cell death by propidium iodide staining, inflammation by Western blot and ELISA assay for cytokine productions, as well as neurological functions by the modified Neurological Severity Score, wire grip and beam walking tests. HMGB1 A-box reversed brain damages in the mice following TBI. It significantly reduced brain edema by protecting integrity of the BBB, ameliorated cell degeneration, and decreased expression of pro-inflammatory cytokines released in injured brain after TBI. These cellular and molecular effects were accompanied by improved behavioral performance in TBI mice. Notably, HMGB1 A-box blocked IL-1β-induced HMGB1 release, and preferentially attenuated TLR4, Myd88 and P65 in astrocyte cultures. Our data suggest that HMGB1 is involved in CCI-induced TBI, which can be inhibited by HMGB1 A-box fragment. Therefore, HMGB1 A-box fragment may have therapeutic potential for the secondary brain damages in TBI. © 2018 The Author(s). Published by S. Karger AG, Basel.

Decreased serum level of HMGB1 and MyD88 during human aging progress in healthy individuals.

Science.gov (United States)

Fu, Guo-Xiang; Chen, Alex F; Zhong, Yuan; Zhao, Jian; Gu, Ying-Jia

2016-04-01

Previous studies have suggested that high mobility group box-1 protein (HMGB1) binds to the toll-like receptor 4 (TLR4) signaling mediates the progression of various inflammatory diseases. But the roles of HMGB1 and TLR4 in aging remain poorly unknown. In this study, we aimed to investigate the serum levels of HMGB1 and myeloid differentiation factor 88 (MyD88), which is one of TLR4's intracellular adaptor proteins during human aging process and their relevance with cathepsin B (CTSB). This research was conducted using the blood samples provided by healthy people (n = 90, 63 men and 27 women). Subjects were subdivided into groups with respect to age: young (about 25 years old, n = 30), middle age (about 40 years old, n = 30), and aged (above 65 years old, n = 30). Altered serum levels of HMGB1, MyD88 and CTSB were measured using an enzyme-linked immunosorbent assay. The serum levels of HMGB1 and MyD88 were significantly decreased in the aged group compared with those in the young group. Linear regression analysis showed that HMGB1 and MyD88 positively correlated with CTSB among the whole healthy people. A negative correlation was determined between MyD88 and age. The serum levels of HMGB1 and MyD88 significantly decreased with age. MyD88, but not HMGB1, was negatively correlated with age.

Rapamycin up-regulates triglycerides in hepatocytes by down-regulating Prox1.

Science.gov (United States)

Kwon, Sora; Jeon, Ji-Sook; Kim, Su Bin; Hong, Young-Kwon; Ahn, Curie; Sung, Jung-Suk; Choi, Inho

2016-02-27

Although the prolonged use of rapamycin may cause unwanted side effects such as hyperlipidemia, the underlying mechanism remains unknown. Prox1 is a transcription factor responsible for the development of several tissues including lymphatics and liver. There is growing evidences that Prox1 participates in metabolism in addition to embryogenesis. However, whether Prox1 is directly related to lipid metabolism is currently unknown. HepG2 human hepatoma cells were treated with rapamycin and total lipids were analyzed by thin layer chromatography. The effect of rapamycin on the expression of Prox1 was determined by western blotting. To investigate the role of Prox1 in triglycerides regulation, siRNA and overexpression system were employed. Rapamycin was injected into mice for 2 weeks and total lipids and proteins in liver were measured by thin layer chromatography and western blot analysis, respectively. Rapamycin up-regulated the amount of triglyceride and down-regulated the expression of Prox1 in HepG2 cells by reducing protein half-life but did not affect its transcript. The loss-of-function of Prox1 was coincident with the increase of triglycerides in HepG2 cells treated with rapamycin. The up-regulation of triglycerides by rapamycin in HepG2 cells reverted to normal levels by the compensation of Prox1 using the overexpression system. Rapamycin also down-regulated Prox1 expression but increased triglycerides in mouse liver. This study suggests that rapamycin can increase the amount of triglycerides by down-regulating Prox1 expression in hepatocytes, which means that the mammalian target of rapamycin (mTOR) signaling is important for the regulation of triglycerides by maintaining Prox1 expression.

Frontline Science: HMGB1 induces neutrophil dysfunction in experimental sepsis and in patients who survive septic shock.

Science.gov (United States)

Grégoire, Murielle; Tadié, Jean-Marc; Uhel, Fabrice; Gacouin, Arnaud; Piau, Caroline; Bone, Nathaniel; Le Tulzo, Yves; Abraham, Edward; Tarte, Karin; Zmijewski, Jaroslaw W

2017-06-01

Sepsis is accompanied by the initial activation of proinflammatory pathways and long-lasting immunosuppression that appears to contribute to late-occurring mortality. Although high-mobility group box 1 (HMGB1) is involved in many aspects of inflammation, its role in sepsis-induced immune suppression remains unclear. In this study, we examined HMGB1's contribution to neutrophil NADPH oxidase activity dysfunction and associated neutrophil-dependent bacterial clearance in mice subjected to sepsis and in patients who survive septic shock. Using a murine model of polymicrobial septic peritonitis, we demonstrated that treatment with anti-HMGB1 Ab significantly diminished sepsis-induced dysfunction of neutrophil NADPH oxidase activity. In a subsequent set of experiments, we found that blocking HMGB1 preserved the ability of neutrophils from patients recovering from septic shock to activate NADPH oxidase. Taken together, our data suggest that HMGB1 accumulation in the late phase of sepsis plays a specific role in the development of postsepsis immunosuppression and specifically affects neutrophil-dependent antibacterial defense mechanisms. Thus, blocking HMGB1 may be a promising therapeutic intervention to diminish the adverse effects of sepsis-induced immunosuppression. © Society for Leukocyte Biology.

Advanced glycation endproduct (AGE) accumulation and AGE receptor (RAGE) up‐regulation contribute to the onset of diabetic cardiomyopathy

Science.gov (United States)

Ma, Heng; Li, Shi‐Yan; Xu, Peisheng; Babcock, Sara A.; Dolence, E. Kurt; Brownlee, Michael; Li, Ji

2008-01-01

Abstract Diabetic cardiomyopathy is manifested by compromised systolic and diastolic function. This study was designed to examine the role of advanced glycation endproduct (AGE) and AGE receptor (RAGE) in diabetic cardiomyopathy. Heart function was assessed in isolated control and streptozotocin‐induced diabetic hearts following in vivo RAGE gene knockdown using RNA interference. Cardiomyocyte mechanical properties were evaluated including peak shortening (PS), time‐to‐PS (TPS) and time‐to‐90% relengthening (TR90). RAGE was assayed by RT‐PCR and immunoblot. Diabetes significantly enhanced cardiac MG, AGE and RAGE levels accompanied with colocalization of AGE and RAGE in cardiomyocytes. Diabetes‐elicited increase in RAGE was inhibited by in vivo siRNA interference. The AGE formation inhibitor benfotiamine significantly attenuated diabetes‐induced elevation in MG, AGE, RAGE and collagen cross‐linking without affecting hypertriglyceridaemia and hypercholesterolaemia in diabetes. Diabetes markedly decreased LV contractility, as evidenced by reduced ±dP/dt and LV developed pressure (LVDP), which were protected by RAGE gene knockdown. In addition, MG‐derived AGE (MG‐AGE) up‐regulated cardiac RAGE mRNA and triggered cardiomyocyte contractile dysfunction reminiscent of diabetic cardiomyopathy. The MG‐AGE‐elicited prolongation of TPS and TR90 was ablated by an anti‐RAGE antibody in cardiomyocytes. Interestingly, MG‐AGE‐induced cardiomyocyte dysfunction was associated with mitochondrial membrane potential (MMP) depolarization and reduced GSK‐3β inactivation in control cardiomyocytes, similar to those from in vivo diabetes. Treatment with siRNA‐RAGE ablated diabetes‐induced MMP depolarization and GSK‐3β inactivation. Collectively, our result implicated a role of AGE‐RAGE in the pathogenesis of diabetic cardiomyopathy. PMID:19602045

HMGB1 Inhibition During Zymosan-Induced Inflammation: The Potential Therapeutic Action of Riboflavin.

Science.gov (United States)

Mazur-Bialy, Agnieszka Irena; Pocheć, Ewa

2016-04-01

Sepsis, also known as systemic inflammatory response syndrome, is a life-threatening condition caused by a pathogenic agent and leading to multiple organ dysfunction syndrome. One of the factors responsible for the excessive intensification of the inflammatory response in the course of inflammation is high-mobility group protein B1 (HMGB1). HMG-1 is a nuclear protein which, after being released to the intercellular space, has a highly pro-inflammatory effect and acts as a late mediator of lethal damage. The purpose of this study was to examine whether the anti-inflammatory action of riboflavin is accompanied by inhibition of HMGB1 release during peritoneal inflammation and zymosan stimulation of macrophages. Peritonitis was induced in male BALB/c and C57BL/6J mice via intraperitoneal injection of zymosan (40 mg/kg). RAW 264.7 macrophages were activated with zymosan (250 µg/ml). Riboflavin (mice, 50 mg/kg; RAW 264.7, 25 µg/ml) was administered 30 min before zymosan, simultaneously with, or 2, 4, 6 h after zymosan. Additionally, mRNA expression of HMGB1 and its intracellular and serum levels were evaluated. The research showed that riboflavin significantly reduces both the expression and the release of HMGB1; however, the effect of riboflavin was time-dependent. The greatest efficacy was found when riboflavin was given 30 min prior to zymosan, and also 2 and 4 h (C57BL/6J; RAW 264.7) or 4 and 6 h (BALB/c) after zymosan. Research showed that riboflavin influences the level of HMGB1 released in the course of inflammation; however, further study is necessary to determine its mechanisms of action.

Mir-22-3p Inhibits Arterial Smooth Muscle Cell Proliferation and Migration and Neointimal Hyperplasia by Targeting HMGB1 in Arteriosclerosis Obliterans

Directory of Open Access Journals (Sweden)

Shui-chuan Huang

2017-08-01

Full Text Available Background: Aberrant vascular smooth muscle cell (VSMC proliferation and migration contribute to the development of vascular pathologies, such as atherosclerosis and post-angioplasty restenosis. The aim of this study was to determine whether miR-22-3p plays a role in regulating human artery vascular smooth muscle cell (HASMC function and neointima formation. Methods: Quantitative real-time PCR (qRT-PCR and fluorescence in situ hybridization (FISH were used to detect miR-22-3p expression in human arteries. Cell Counting Kit-8 (CCK-8 and EdU assays were performed to assess cell proliferation, and transwell and wound closure assays were performed to assess cell migration. Moreover, luciferase reporter assays were performed to identify the target genes of miR-22-3p. Finally, a rat carotid artery balloon-injury model was used to determine the role of miR-22-3p in neointima formation. Results: MiR-22-3p expression was downregulated in arteriosclerosis obliterans (ASO arteries compared with normal arteries, as well as in platelet-derived growth factor-BB (PDGF-BB-stimulated HASMCs compared with control cells. MiR-22-3p overexpression had anti-proliferative and anti-migratory effects and dual-luciferase assay showed that high mobility group box-1 (HMGB1 is a direct target of miR-22-3p in HASMCs. Furthermore, miR-22-3p expression was negatively correlated with HMGB1 expression in ASO tissue specimens. Finally, LV-miR-22-3p-mediated miR-22-3p upregulation significantly suppressed neointimal hyperplasia specifically by reducing HMGB1 expression in vivo. Conclusions: Our results indicate that miR-22-3p is a key molecule in regulating HASMC proliferation and migration by targeting HMGB1 and that miR-22-3p and HMGB1 may be therapeutic targets in the treatment of human ASO.

Expression of HMGB1 and HMGN2 in gingival tissues, GCF and PICF of periodontitis patients and peri-implantitis

Directory of Open Access Journals (Sweden)

Ping Xie

2011-09-01

Full Text Available High mobility group chromosomal protein B1 (HMGB1 and N2 (HMGN2, two members of High mobility group (HMG family, play important role in inflammation. The purposes of this study were to investigate the expression of HMGB1 and HMGN2 in periodontistis. The expression of HMGB1 and HMGN2 mRNA in gingival tissues and gingival crevicular fluid (GCF in chronic periodontitis (CP, generalized aggressive periodontitis (G-AgP patients and healthy subjects was detected by real-time PCR. The protein level of HMGB1 and HMGN2 in peri-implant crevicular fluid (PICF, peri-implant crevicular fluid of peri-implantitis (PI-PICF and normal patients was determined by Western blotting. Furthermore, IL-1β, IL-6, IL-8, TNF-α and HMGB1 levels in GCF, PI-PICF and healthy-PICF samples from different groups were determined by ELISA. HMGN2 expression was increased in inflamed gingival tissues and GCF from CP and G-ApG groups compared to control group. HMGB1 expression was the highest in the gingival tissues and GCF from CP patients and was accompanied by increased concentrations of IL-1β, IL-6, IL-8 proinflammaory cytokines. To our knowledge, this is the first study reporting that the expression of HMGB1 and HMGN2 was increased in the gingival tissues and GCF in CP and G-AgP and the PICF in PICF. Our data suggest that HMGB1 may be a potential target for the therapy of periodontitis and PI.

HMGB in mollusk Crassostrea ariakensis Gould: structure, pro-inflammatory cytokine function characterization and anti-infection role of its antibody.

Directory of Open Access Journals (Sweden)

Ting Xu

Full Text Available BACKGROUND: Crassostrea ariakensis Gould is a representative bivalve species and an economically important oyster in China, but suffers severe mortalities in recent years that are caused by rickettsia-like organism (RLO. Prevention and control of this disease is a priority for the development of oyster aquaculture. It has been proven that mammalian HMGB (high mobility group box can be released extracellularly and acts as an important pro-inflammatory cytokine and late mediator of inflammatory reactions. In vertebrates, HMGB's antibody (anti-HMGB has been shown to confer significant protection against certain local and systemic inflammatory diseases. Therefore, we investigated the functions of Ca-HMGB (oyster HMGB and anti-CaHMGB (Ca-HMGB's antibody in oyster RLO/LPS (RLO or LPS-induced disease or inflammation. METHODOLOGY/PRINCIPAL FINDINGS: Sequencing analysis revealed Ca-HMGB shares conserved structures with mammalians. Tissue-specific expression indicates that Ca-HMGB has higher relative expression in hemocytes. Significant continuous up-regulation of Ca-HMGB was detected when the hemocytes were stimulated with RLO/LPS. Recombinant Ca-HMGB protein significantly up-regulated the expression levels of some cytokines. Indirect immunofluorescence study revealed that Ca-HMGB localized both in the hemocyte nucleus and cytoplasm before RLO challenge, but mainly in the cytoplasm 12 h after challenge. Western blot analysis demonstrated Ca-HMGB was released extracellularly 4-12 h after RLO challenge. Anti-CaHMGB was added to the RLO/LPS-challenged hemocyte monolayer and real-time RT-PCR showed that administration of anti-CaHMGB dramatically reduced the rate of RLO/LPS-induced up-regulation of LITAF at 4-12 h after treatment. Flow cytometry analysis indicated that administration of anti-CaHMGB reduced RLO/LPS-induced hemocyte apoptosis and necrosis rates. CONCLUSIONS/SIGNIFICANCE: Ca-HMGB can be released extracellularly and its subcellular localization

Nucleosome dynamics: HMGB1 facilitates nucleosome restructuring and collaborates in estrogen-responsive gene expression

Directory of Open Access Journals (Sweden)

William M. Scovell

2016-12-01

Full Text Available The genome in the human cell is extraordinarily compacted in the nucleus. As a result, much of the DNA is inaccessible and functionally inert. Notwithstanding the highly efficient packaging, mechanisms have evolved to render DNA sites accessible that then enable a multitude of factors to carry out ongoing and vital functions. The compaction is derived from DNA complexation within nucleosomes, which can further consolidate into a higher-order chromatin structure. The nucleosome and nucleosomal DNA are not static in nature, but are dynamic, undergoing structural and functional changes as the cell responds to stresses and/or metabolic or environmental cues. We are only beginning to understand the forces and the complexes that engage the nucleosome to unearth the tightly bound and inaccessible DNA sequences and provide an opening to more accessible target sites. In many cases, current findings support a major role for the action of ATP-dependent chromatin remodeling complexes (CRCs in providing an avenue to factor accessibility that leads to the activation of transcription. The estrogen receptor α (ERα does not bind to the estrogen response element (ERE in the canonical nucleosome. However, evidence will be presented that HMGB1 restructures the nucleosome in an ATP-independent manner and also facilitates access and strong binding of ERα to ERE. The features that appear important in the mechanism of action for HMGB1 will be highlighted, in addition to the characteristic features of the restructured nucleosome. These findings, together with previous evidence, suggest a collaborative role for HMGB1 in the step-wise transcription of estrogen-responsive genes. In addition, alternate mechanistic pathways will be discussed, with consideration that “HMGB1 restructuring” of the nucleosome may generally be viewed as a perturbation of the equilibrium of an ensemble of nearly isoenergetic nucleosome states in an energy landscape that is driven by

DMBT1 expression is down-regulated in breast cancer

DEFF Research Database (Denmark)

Braidotti, P; Nuciforo, P G; Mollenhauer, J

2004-01-01

and hyperplastic mammary cells positive with DMBTh12 were also MCM5-positive. CONCLUSIONS: The redistribution and up-regulation of DMBT1 in normal and hyperplastic tissues flanking malignant tumours and its down-regulation in carcinomas suggests a potential role in breast cancer. Moreover, the concomitant......BACKGROUND: We studied the expression of DMBT1 (deleted in malignant brain tumor 1), a putative tumor suppressor gene, in normal, proliferative, and malignant breast epithelium and its possible relation to cell cycle. METHODS: Sections from 17 benign lesions and 55 carcinomas were immunostained...... expression was down-regulated in the cancerous lesions compared to the normal and/or hyperplastic epithelium adjacent to carcinomas (3/55 positive carcinomas versus 33/42 positive normal/hyperplastic epithelia; p = 0.0001). In 72% of cases RT-PCR confirmed immunohistochemical results. Most of normal...

Diet Restriction Inhibits Apoptosis and HMGB1 Oxidation and Promotes Inflammatory Cell Recruitment during Acetaminophen Hepatotoxicity

Science.gov (United States)

Antoine, Daniel James; Williams, Dominic P; Kipar, Anja; Laverty, Hugh; Park, B Kevin

2010-01-01

Acetaminophen (APAP) overdose is a major cause of acute liver failure and serves as a paradigm to elucidate mechanisms, predisposing factors and therapeutic interventions. The roles of apoptosis and inflammation during APAP hepatotoxicity remain controversial. We investigated whether fasting of mice for 24 h can inhibit APAP-induced caspase activation and apoptosis through the depletion of basal ATP. We also investigated in fasted mice the critical role played by inhibition of caspase-dependent cysteine 106 oxidation within high mobility group box-1 protein (HMGB1) released by ATP depletion in dying cells as a mechanism of immune activation. In fed mice treated with APAP, necrosis was the dominant form of hepatocyte death. However, apoptosis was also observed, indicated by K18 cleavage, DNA laddering and procaspase-3 processing. In fasted mice treated with APAP, only necrosis was observed. Inflammatory cell recruitment as a consequence of hepatocyte death was observed only in fasted mice treated with APAP or fed mice cotreated with a caspase inhibitor. Hepatic inflammation was also associated with loss in detection of serum oxidized-HMGB1. A significant role of HMGB1 in the induction of inflammation was confirmed with an HMGB1-neutralizing antibody. The differential response between fasted and fed mice was a consequence of a significant reduction in basal hepatic ATP, which prevented caspase processing, rather than glutathione depletion or altered APAP metabolism. Thus, the inhibition of caspase-driven apoptosis and HMGB1 oxidation by ATP depletion from fasting promotes an inflammatory response during drug-induced hepatotoxicity/liver pathology. PMID:20811657

Effects of RAGE-Specific Inhibitor FPS-ZM1 on Amyloid-β Metabolism and AGEs-Induced Inflammation and Oxidative Stress in Rat Hippocampus.

Science.gov (United States)

Hong, Yan; Shen, Chao; Yin, Qingqing; Sun, Menghan; Ma, Yingjuan; Liu, Xueping

2016-05-01

An increased level of advanced glycation end products (AGEs) is observed in brains of patients with Alzheimer's disease (AD). AGEs and receptor for AGEs (RAGE) play important roles in the pathogenesis of AD. FPS-ZM1 is a high-affinity RAGE-specific blocker that inhibits amyloid-β binding to RAGE, neurological damage and inflammation in the APP(sw/0) transgenic mouse model of AD. FPS-ZM1 is not toxic to mice and can easily cross the blood-brain barrier. In this study, an AGEs-RAGE-activated rat model were established by intrahippocampal injection of AGEs, then these rats were treated with intraperitoneal administration of FPS-ZM1 and the possible neuroprotective effects were investigated. We found that AGEs administration induced an-regulation of Abeta production, inflammation, and oxidative stress, and an increased escape latency of rats in the Morris water maze test, all of these are significantly reduced by FPS-ZM1 treatment. Our results suggest that the AGEs-RAGE pathway is responsible for cognitive deficits, and therefore may be a potential treatment target. FPS-ZM1 might be a novel therapeutic agent to treat AD patients.

Down-regulated miR-448 relieves spinal cord ischemia/reperfusion injury by up-regulating SIRT1

Directory of Open Access Journals (Sweden)

Yun Wang

2018-03-01

Full Text Available MicroRNAs play a crucial role in the progression of spinal cord ischemia/reperfusion injury (SCII. The role of miR-448 and SIRT1 in SCII was investigated in this study, to provide further insights into prevention and improvement of this disorder. In this study, expressions of miR-448 and SIRT1 protein were determined by qRT-PCR and western blot, respectively. Flow cytometry was used to analyze cell apoptosis. The endogenous expression of genes was modulated by recombinant plasmids and cell transfection. Dual-luciferase reporter assay was performed to determine the interaction between miR-448 and SIRT1. The Basso, Beattie, and Bresnahan score was used to measure the hind-limb function of rat. The spinal cord ischemia reperfusion injury model of adult rats was developed by abdominal aorta clamping, and the nerve function evaluation was completed by motor deficit index score. In SCII tissues and cells treated with hypoxia, miR-448 was up-regulated while SIRT1 was down-regulated. Hypoxia treatment reduced the expression of SIRT1 through up-regulating miR-448 in nerve cells. Up-regulation of miR-448 induced by hypoxia promoted apoptosis of nerve cells through down-regulating SIRT1. Down-regulated miR-448 improved neurological function and hind-limb motor function of rats with SCII by up-regulating SIRT1. Down-regulated miR-448 inhibited apoptosis of nerve cells and improved neurological function by up-regulating SIRT1, which contributes to relieving SCII.

Plasma concentration of high-mobility group box 1 (HMGB1) after 100 drop to vertical jumps and after a 1200-km bicycle race.

Science.gov (United States)

Behringer, M; Kilian, Y; Montag, J; Geesmann, B; Mester, J

2016-01-01

High-mobility group box 1 (HMGB1) has recently been reported to be involved in proinflammation and tissue repair. Therefore, we hypothesized that HMGB1 is released into the bloodstream after eccentric exercises or prolonged endurance activities. Blood samples from 11 participants that performed 100 drop to vertical jumps (DVJ) and from 10 participants that took part in the 1200-km 'Paris-Brest-Paris' bicycle race (PBP) were tested for HMGB1 and creatine kinase (CK) levels. CK increased after both DVJ (pre: 150.6 ± 81.5 U/L; post: 188.8 ± 95.5 U/L 8 h: 790.5 ± 346.4 U/L) and PBP (pre: 81.3 ± 36.4 U/L; post: 725.2 ± 229.5 U/L; 12 h: 535.8 ± 188.6 U/L), indicating membrane damage. However, HMGB1 plasma levels remained below the detection limit (78 pg/mL) of the applied enzyme-linked immunosorbent assay kit for all blood samples analysed. That is, neither high intensity eccentric exercises (DVJ) nor prolonged endurance events (PBP) seemed to affect HMGB1 levels in blood at selected time points.

HMGB1 exacerbates experimental mouse colitis by enhancing innate lymphoid cells 3 inflammatory responses via promoted IL-23 production.

Science.gov (United States)

Chen, Xiangyu; Li, Lingyun; Khan, Muhammad Noman; Shi, Lifeng; Wang, Zhongyan; Zheng, Fang; Gong, Feili; Fang, Min

2016-11-01

In inflammatory bowel diseases (IBD), high mobility group box 1 (HMGB1), as an endogenous inflammatory molecule, can promote inflammatory cytokines secretion by acting on TLR2/4 resulting in tissue damage. The underlying mechanisms remain unclear. Here we report a novel role of HMGB1 in controlling the maintenance and function of intestine-resident group-3 innate lymphoid cells (ILC3s) that are important innate effector cells implicated in mucosal homeostasis and IBD pathogenesis. We showed that mice treated with anti-HMGB1 Ab, or genetically deficient for TLR2 -/- or TLR4 -/- mice, displayed reduced intestinal inflammation. In these mice, the numbers of colonic ILC3s were significantly reduced, and the levels of IL-17 and IL-22 that can be secreted by ILC3s were also decreased in the colon tissues. Furthermore, HMGB1 promoted DCs via TLR2/4 signaling to produce IL-23, activating ILC3s to produce IL-17 and IL-22. Our data thus indicated that the HMGB1-TLR2/4-DCs-IL-23 cascade pathway enhances the functions of ILC3s to produce IL-17 and IL-22, and this signal way might play a vital role in the development of IBD.

Up-regulation of TLR2 and TLR4 in high mobility group Box1-stimulated macrophages in pulpitis patients

Science.gov (United States)

Mahmoudi, Javad; Sabermarouf, Babak; Baradaran, Behzad; Sadat-Hatamnezhad, Leila; Shotorbani, Siamak Sandoghchian

2017-01-01

Objective(s): High Mobility Group Box1 (HMGB1) is a nonhistone, DNA-binding protein that serves a crucial role in regulating gene transcription and is involved in a variety of proinflammatory, extracellular activities. The aim of this study was to explore whether HMGB1 stimulation can up-regulate the expression of Toll-like Receptor 2 (TLR2) and Toll-like Receptor 4 (TLR4) on macrophages from pulpitis and to clarify the subsequent events involving Th17 cells and Th17 cell-associated cytokine changes. Materials and Methods: Having prepared dental pulp tissues of pulpitis and healthy controls, macrophage were isolated and cultured. Macrophages were thereafter stimulated by HMGB1 time course. RT-QPCR, flowcytometer, immunofluorescence, Western blotting, and ELISA techniques were used in the present research. Results: Our results showed that the expression of TLR2 and TLR4 on macrophages stimulated with HMGB1 increased in pulpitis compared with controls (macrophages without HMGB1 stimulation) with a statistical significance (Ppulpitis increased, and NF-kB, the downstream target of TLR2 and TLR4, also showed a marked elevation after macrophages’ stimulation by HMGB1. Conclusion: The evidence from the present study suggests that the enhanced TLR2 and TLR4 pathways and Th17 cell polarization may be due to HMGB1 stimulation in pulpitis. PMID:28293399

HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

Directory of Open Access Journals (Sweden)

Héla Saïdi

2016-02-01

Full Text Available Plasmacytoid dendritic cells (pDCs are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7 and 9 (TLR9 ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN

HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

Science.gov (United States)

Saïdi, Héla; Bras, Marlène; Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

2016-02-01

Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN

HMGB1-dependent triggering of HIV-1 replication and persistence in dendritic cells as a consequence of NK-DC cross-talk.

Directory of Open Access Journals (Sweden)

Héla Saïdi

Full Text Available HIV-1 has evolved ways to exploit DCs, thereby facilitating viral dissemination and allowing evasion of antiviral immunity. Recently, the fate of DCs has been found to be extremely dependent on the interaction with autologous NK cells, but the mechanisms by which NK-DC interaction controls viral infections remain unclear. Here, we investigate the impact of NK-DC cross-talk on maturation and functions of HIV-infected immature DCs.Immature DCs were derived from primary monocytes, cultured in the presence of IL-4 and GM-CSF. In some experiments, DCs were infected with R5-HIV-1(BaL or X4-HIV-1(NDK, and viral replication, proviral HIV-DNA and the frequency of infected DCs were measured. Autologous NK cells were sorted and either kept unstimulated in the presence of suboptimal concentration of IL-2, or activated by a combination of PHA and IL-2. The impact of 24 h NK-DC cross-talk on the fate of HIV-1-infected DCs was analyzed. We report that activated NK cells were required for the induction of maturation of DCs, whether uninfected or HIV-1-infected, and this process involved HMGB1. However, the cross-talk between HIV-1-infected DCs and activated NK cells was functionally defective, as demonstrated by the strong impairment of DCs to induce Th1 polarization of naïve CD4 T cells. This was associated with the defective production of IL-12 and IL-18 by infected DCs. Moreover, the crosstalk between activated NK cells and HIV-infected DCs resulted in a dramatic increase in viral replication and proviral DNA expression in DCs. HMGB1, produced both by NK cells and DCs, was found to play a pivotal role in this process, and inhibition of HMGB1 activity by glycyrrhizin, known to bind specifically to HMGB1, or blocking anti-HMGB1 antibodies, abrogated NK-dependent HIV-1 replication in DCs.These observations provide evidence for the crucial role of NK-DC cross-talk in promoting viral dissemination, and challenge the question of the in vivo involvement of HMGB1

Role of IL-1 beta and 5-HT2 receptors in midbrain periaqueductal gray (PAG) in potentiating defensive rage behavior in cat.

Science.gov (United States)

Bhatt, Suresh; Bhatt, Rekha; Zalcman, Steven S; Siegel, Allan

2008-02-01

Feline defensive rage, a form of aggressive behavior that occurs in response to a threat can be elicited by electrical stimulation of the medial hypothalamus or midbrain periaqueductal gray (PAG). Our laboratory has recently begun a systematic examination of the role of cytokines in the regulation of rage and aggressive behavior. It was shown that the cytokine, interleukin-2 (IL-2), differentially modulates defensive rage when microinjected into the medial hypothalamus and PAG by acting through separate neurotransmitter systems. The present study sought to determine whether a similar relationship exists with respect to interleukin 1-beta (IL-1 beta), whose receptor activation in the medial hypothalamus potentiates defensive rage. Thus, the present study identified the effects of administration of IL-1 beta into the PAG upon defensive rage elicited from the medial hypothalamus. Microinjections of IL-1 beta into the dorsal PAG significantly facilitated defensive rage behavior elicited from the medial hypothalamus in a dose and time dependent manner. In addition, the facilitative effects of IL-1 beta were blocked by pre-treatment with anti-IL-1 beta receptor antibody, while IL-1 beta administration into the PAG had no effect upon predatory attack elicited from the lateral hypothalamus. The findings further demonstrated that IL-1 beta's effects were mediated through 5-HT(2) receptors since pretreatment with a 5-HT(2C) receptors antagonist blocked the facilitating effects of IL-1 beta. An extensive pattern of labeling of IL-1 beta and 5-HT(2C) receptors in the dorsal PAG supported these findings. The present study demonstrates that IL-beta in the dorsal PAG, similar to the medial hypothalamus, potentiates defensive rage behavior and is mediated through a 5-HT(2C) receptor mechanism.

HMGB1 is negatively correlated with the development of endometrial carcinoma and prevents cancer cell invasion and metastasis by inhibiting the process of epithelial-to-mesenchymal transition

Directory of Open Access Journals (Sweden)

Luan XR

2017-03-01

Full Text Available Xiaorong Luan,1,2 Chunjing Ma,2 Ping Wang,2 Fenglan Lou1 1Nursing College, Shandong University, 2Qilu Hospital of Shandong University, Jinan, People’s Republic of China Abstract: High-mobility group box protein 1 (HMGB1, a nuclear protein that plays a significant role in DNA architecture and transcription, was correlated with the progression of some types of cancer. However, the role of HMGB1 in endometrial cancer cell invasion and metastasis remains unexplored. HMGB1 expression was initially assessed by immunohistochemistry and reverse transcription-quantitative polymerase chain reaction (RT-qPCR in normal endometrial tissue and endometrial carcinoma tissue. High expressions of HMGB1 protein were detected in normal endometrial tissues; however, in endometrial cancer tissues, the expressions of HMGB1 were found to be very weak. Furthermore, HMGB1 expressions were negatively correlated with advanced stage and lymph node metastasis in endometrial cancer. Then by RT-qPCR, Western blot and immunocytochemistry, HMGB1 was also detected in primary cultured endometrial cells and four kinds of endometrial cancer cell lines (Ishikawa, HEC-1A, HEC-1B and KLE. We found that the expression of HMGB1 was much higher in normal endometrial cells than in endometrial cancer cells, and reduced expression levels of HMGB1 were observed especially in the highly metastatic cell lines. Using lentivirus transfection, HMGB1 small hairpin RNA was constructed, and this infected the lowly invasive endometrial cancer cell lines, Ishikawa and HEC-1B. HMGB1 knockdown significantly enhanced the proliferation, invasion and metastasis of endometrial cancer cells and induced the process of epithelial-to-mesenchymal transition. These results can contribute to the development of a new potential therapeutic target for endometrial cancer. Keywords: HMGB1, endometrial cancer, invasion, metastasis, epithelial-to-mesenchymal transition

Radical Roles for RAGE in the Pathogenesis of Oxidative Stress in Cardiovascular Diseases and Beyond

Directory of Open Access Journals (Sweden)

Radha Ananthakrishnan

2013-10-01

Full Text Available Oxidative stress is a central mechanism by which the receptor for advanced glycation endproducts (RAGE mediates its pathological effects. Multiple experimental inquiries in RAGE-expressing cultured cells have demonstrated that ligand-RAGE interaction mediates generation of reactive oxygen species (ROS and consequent downstream signal transduction and regulation of gene expression. The primary mechanism by which RAGE generates oxidative stress is via activation of NADPH oxidase; amplification mechanisms in the mitochondria may further drive ROS production. Recent studies indicating that the cytoplasmic domain of RAGE binds to the formin mDia1 provide further support for the critical roles of this pathway in oxidative stress; mDia1 was required for activation of rac1 and NADPH oxidase in primary murine aortic smooth muscle cells treated with RAGE ligand S100B. In vivo, in multiple distinct disease models in animals, RAGE action generates oxidative stress and modulates cellular/tissue fate in range of disorders, such as in myocardial ischemia, atherosclerosis, and aneurysm formation. Blockade or genetic deletion of RAGE was shown to be protective in these settings. Indeed, beyond cardiovascular disease, evidence is accruing in human subjects linking levels of RAGE ligands and soluble RAGE to oxidative stress in disorders such as doxorubicin toxicity, acetaminophen toxicity, neurodegeneration, hyperlipidemia, diabetes, preeclampsia, rheumatoid arthritis and pulmonary fibrosis. Blockade of RAGE signal transduction may be a key strategy for the prevention of the deleterious consequences of oxidative stress, particularly in chronic disease.

Mechanisms Down-Regulating Sprouty1, a Growth Inhibitor in Prostate Cancer

National Research Council Canada - National Science Library

Kwabi-Addo, Bernard

2006-01-01

.... I have demonstrated that Sprouty1 is down-regulated in human prostate cancer (PCa). The purpose of the present study is to characterize the molecular mechanisms regulating Sprouty1 expression in the human PCa. Results...

Expression and clinical implication of Beclin1, HMGB1, p62, survivin, BRCA1 and ERCC1 in epithelial ovarian tumor tissues.

Science.gov (United States)

Ju, L-L; Zhao, C Y; Ye, K-F; Yang, H; Zhang, J

2016-05-01

The aim of the present study is to investigate the differential expression of Beclin1, HMGB1, p62, survivin, ERCC1 and BRCA1 protein in epithelial ovarian cancer (EOC) and to evaluate the relationship between autophagy and platinum resistance of EOC patients during platinum-based chemotherapy with the protein expression. Expression of Beclin1, HMGB1, p62, survivin, ERCC1 and BRCA1 were detected with immunohistochemistry in 60 patients, including 39 with epithelial ovarian cancer (EOC), 13 benign epithelial ovarian tumor tissue (BET) and 8 borderline ovarian tumor tissue. Beclin, p62 and ERCC1 expression was significantly higher in the EOC than the BET (p0.05). BRCA1 expression was lower in EOC than BET (pepithelial ovarian cancer.

High mobility group box-1 is phosphorylated by protein kinase C zeta and secreted in colon cancer cells

International Nuclear Information System (INIS)

Lee, Hanna; Park, Minhee; Shin, Nara; Kim, Gamin; Kim, Yun Gi; Shin, Jeon-Soo; Kim, Hoguen

2012-01-01

Highlights: ► Specific enzyme for HMGB1 phosphorylation and its secretion is proposed. ► Inhibition of PKC-ζ leads to significant reduction of the secreted HMGB1. ► Phosphorylation of specific site of HMGB1 redirects its secretion in cancer cells. ► Activation of PKC-ζ in cancers explains the enhanced HMGB1 secretion. -- Abstract: High mobility group box-1 (HMGB1), a nuclear protein, is overexpressed and secreted in cancer cells. Phosphorylation on two different nuclear localization signal regions are known to be important for the nuclear-to-cytoplasmic transport and secretion of HMGB1. However, little is known about the biochemical mechanism of HMGB1 modifications and its subsequent secretion from cancer cells. To identify the specific enzyme and important sites for HMGB1 phosphorylation, we screened the protein kinase C (PKC) family in a colon cancer cell line (HCT116) for HMGB1 binding by pull-down experiments using a 3XFLAG-HMGB1 construct. Strong interactions between atypical PKCs (PKC-ζ, λ, and ι) and cytoplasmic HMGB1 were observed in HCT116 cells. We further identified the most critical PKC isotype that regulates HMGB1 secretion is PKC-ζ by using PKC inhibitors and siRNA experiments. The serine residues at S39, S53 and S181 of HMGB1 were related to enhancing HMGB1 secretion. We also demonstrated overexpression and activation of PKC-ζ in colon cancer tissues. Our findings suggest that PKC-ζ is involved in the phosphorylation of HMGB1, and the phosphorylation of specific serine residues in the nuclear localization signal regions is related to enhanced HMGB1 secretion in colon cancer cells.

HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure

Directory of Open Access Journals (Sweden)

Runkuan Yang

2017-01-01

Full Text Available Acute liver failure (ALF is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT. BT triggers/induces systemic inflammatory responses syndrome (SIRS, which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure.

Science.gov (United States)

Yang, Runkuan; Zou, Xiaoping; Tenhunen, Jyrki; Tønnessen, Tor Inge

2017-01-01

Acute liver failure (ALF) is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF) and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT). BT triggers/induces systemic inflammatory responses syndrome (SIRS), which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

Contrast Media-Induced Renal Inflammation Is Mediated Through HMGB1 and Its Receptors in Human Tubular Cells.

Science.gov (United States)

Guan, Xiao-Feng; Chen, Qing-Jie; Zuo, Xiao-Cong; Guo, Ren; Peng, Xiang-Dong; Wang, Jiang-Lin; Yin, Wen-Jun; Li, Dai-Yang

2017-01-01

With the rapid development of imaging diagnosis and interventional therapy, contrast media (CM) are widely used in clinics. However, contrast-induced nephropathy (CIN) is the third leading cause of hospital-acquired acute renal failure accounting for 10-12% of all causes of hospital-acquired renal failure. Recent study found that inflammation may participate in the pathogenesis of CIN, but the role of it remains unclear. HK-2 cells were treated with Iohexol, Urografin, and mannitol. Two types of CM increased the release of HMGB1 in cell supernatant accompanied by increased expression of TLR2 and CXCR4. Iohexol and Urografin also caused a significant increase in NF-κB followed by the release of IL-6 and MCP-1. To clarify the role of HMGB1, TLR2, and CXCR4, glycyrrhizin, anti-TLR2-IgG, and AMD3100 were used to inhibit HMGB1, TLR2, and CXCR4, respectively. Significant decrease in the expression of TLR2, CXCR4, nuclear NF-κB, and the release of IL-6 and MCP-1 were observed. These results indicate that TLR2 and CXCR4 signaling are involved in CM-induced HK-2 cell injury model in an HMGB1-dependent pathway, which may provide a new target for the prevention and the treatment of CIN.

DMBT1 expression is down-regulated in breast cancer

International Nuclear Information System (INIS)

Braidotti, P; Pietra, GG; Nuciforo, PG; Mollenhauer, J; Poustka, A; Pellegrini, C; Moro, A; Bulfamante, G; Coggi, G; Bosari, S

2004-01-01

We studied the expression of DMBT1 (deleted in malignant brain tumor 1), a putative tumor suppressor gene, in normal, proliferative, and malignant breast epithelium and its possible relation to cell cycle. Sections from 17 benign lesions and 55 carcinomas were immunostained with anti DMBT1 antibody (DMBTh12) and sections from 36 samples, were double-stained also with anti MCM5, one of the 6 pre-replicative complex proteins with cell proliferation-licensing functions. DMBT1 gene expression at mRNA level was assessed by RT-PCR in frozen tissues samples from 39 patients. Normal glands and hyperplastic epithelium in benign lesions displayed a luminal polarized DMBTh12 immunoreactivity. Normal and hyperplastic epithelium adjacent to carcinomas showed a loss of polarization, with immunostaining present in basal and perinuclear cytoplasmic compartments. DMBT1 protein expression was down-regulated in the cancerous lesions compared to the normal and/or hyperplastic epithelium adjacent to carcinomas (3/55 positive carcinomas versus 33/42 positive normal/hyperplastic epithelia; p = 0.0001). In 72% of cases RT-PCR confirmed immunohistochemical results. Most of normal and hyperplastic mammary cells positive with DMBTh12 were also MCM5-positive. The redistribution and up-regulation of DMBT1 in normal and hyperplastic tissues flanking malignant tumours and its down-regulation in carcinomas suggests a potential role in breast cancer. Moreover, the concomitant expression of DMTB1 and MCM5 suggests its possible association with the cell-cycle regulation

HMGB1 and Histones Play a Significant Role in Inducing Systemic Inflammation and Multiple Organ Dysfunctions in Severe Acute Pancreatitis

Directory of Open Access Journals (Sweden)

Runkuan Yang

2017-01-01

Full Text Available Severe acute pancreatitis (SAP starts as a local inflammation of pancreatic tissue that induces the development of multiple extrapancreatic organs dysfunction; however, the underlying mechanisms are still not clear. Ischemia-reperfusion, circulating inflammatory cytokines, and possible bile cytokines significantly contribute to gut mucosal injury and intestinal bacterial translocation (BT during SAP. Circulating HMGB1 level is significantly increased in SAP patients and HMGB1 is an important factor that mediates (at least partly gut BT during SAP. Gut BT plays a critical role in triggering/inducing systemic inflammation/sepsis in critical illness, and profound systemic inflammatory response syndrome (SIRS can lead to multiple organ dysfunction syndrome (MODS during SAP, and systemic inflammation with multiorgan dysfunction is the cause of death in experimental SAP. Therefore, HMGB1 is an important factor that links gut BT and systemic inflammation. Furthermore, HMGB1 significantly contributes to multiple organ injuries. The SAP patients also have significantly increased circulating histones and cell-free DNAs levels, which can reflect the disease severity and contribute to multiple organ injuries in SAP. Hepatic Kupffer cells (KCs are the predominant source of circulating inflammatory cytokines in SAP, and new evidence indicates that hepatocyte is another important source of circulating HMGB1 in SAP; therefore, treating the liver injury is important in SAP.

T1 mapping of the mouse brain following fractionated manganese administration using MP2RAGE.

Science.gov (United States)

Driencourt, Luc; Romero, Carola Jacqueline; Lepore, Mario; Eggenschwiler, Florent; Reynaud, Olivier; Just, Nathalie

2017-01-01

With the increasing development of transgenic mouse models of neurodegenerative diseases allowing improved understanding of the underlying mechanisms of these disorders, robust quantitative mapping techniques are also needed in rodents. MP2RAGE has shown great potential for structural imaging in humans at high fields. In the present work, MP2RAGE was successfully implemented at 9.4T and 14.1T. Following fractionated injections of MnCl 2 , MP2RAGE images were acquired allowing simultaneous depiction and T 1 mapping of structures in the mouse brain at both fields. In addition, T 1 maps demonstrated significant T 1 shortenings in different structures of the mouse brain (p < 0.0008 at 9.4T, p < 0.000001 at 14.1T). T 1 values recovered to the levels of saline-injected animals 1 month after the last injection except in the pituitary gland. We believe that MP2RAGE represents an important prospective translational tool for further structural MRI.

The association of HMGB1 expression with clinicopathological significance and prognosis in Asian patients with colorectal carcinoma: a meta-analysis and literature review

Directory of Open Access Journals (Sweden)

Zhang XL

2016-08-01

Full Text Available Xiaoli Zhang,1,2 Jinming Yu,1,2 Minghuan Li,2 Hui Zhu,2 Xindong Sun,2 Li Kong2 1Department of Oncology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, 2Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan, Shandong Province, People’s Republic of China Background: The association of high mobility group box 1 (HMGB1 expression with clinicopathological significance and prognosis in Asian patients with colorectal carcinoma (CRC remains controversial. The purpose of this study was to conduct a meta-analysis and literature review to identify the role of HMGB1 in the development and prognosis of CRC in Asians. Methods: All eligible studies regarding the association between HMGB1 expression in tissue with clinicopathological significance and prognosis in Asian patients with CRC published up to January 2015 were identified by searching PubMed, Web of Science, Chinese National Knowledge Infrastructure, and WanFang database. Analysis of pooled data was performed, while odds ratio (OR or hazard radio with 95% confidence interval (CI was calculated and summarized to evaluate the strength of this association in fixed- or random-effects model. Results: The expression level of HMGB1 in CRC tissues was much higher than normal colorectal tissues (OR =27.35, 95% CI 9.32–80.26, P<0.0001 and para-tumor colorectal tissues (OR =10.06, 95% CI 4.61–21.95, P<0.0001. There was no relation between the HMGB1 expression and sex, age, clinical T stage, tumor size, and location (colon or rectum cancer. However, a significant relation was detected between the HMGB1 expression and clinical stage (American Joint Committee on Cancer 7, lymph node metastasis, distant metastasis, tumor invasion depth, and differentiation rate (P=0.002, P≤0.0001, P<0.0001, P<0.0001, and P=0.007, respectively. Patients with higher HMGB1 expression had shorter overall survival time, whereas patients with lower level of HMGB1 had better survival (hazard

High mobility group box-1 is phosphorylated by protein kinase C zeta and secreted in colon cancer cells

Energy Technology Data Exchange (ETDEWEB)

Lee, Hanna; Park, Minhee; Shin, Nara; Kim, Gamin [Department of Pathology, Yonsei University College of Medicine, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul (Korea, Republic of); Kim, Yun Gi [Department of Internal Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744 (Korea, Republic of); Shin, Jeon-Soo [Department of Microbiology, Yonsei University College of Medicine, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul (Korea, Republic of); Kim, Hoguen, E-mail: hkyonsei@yuhs.ac [Department of Pathology, Yonsei University College of Medicine, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul (Korea, Republic of)

2012-07-27

Highlights: Black-Right-Pointing-Pointer Specific enzyme for HMGB1 phosphorylation and its secretion is proposed. Black-Right-Pointing-Pointer Inhibition of PKC-{zeta} leads to significant reduction of the secreted HMGB1. Black-Right-Pointing-Pointer Phosphorylation of specific site of HMGB1 redirects its secretion in cancer cells. Black-Right-Pointing-Pointer Activation of PKC-{zeta} in cancers explains the enhanced HMGB1 secretion. -- Abstract: High mobility group box-1 (HMGB1), a nuclear protein, is overexpressed and secreted in cancer cells. Phosphorylation on two different nuclear localization signal regions are known to be important for the nuclear-to-cytoplasmic transport and secretion of HMGB1. However, little is known about the biochemical mechanism of HMGB1 modifications and its subsequent secretion from cancer cells. To identify the specific enzyme and important sites for HMGB1 phosphorylation, we screened the protein kinase C (PKC) family in a colon cancer cell line (HCT116) for HMGB1 binding by pull-down experiments using a 3XFLAG-HMGB1 construct. Strong interactions between atypical PKCs (PKC-{zeta}, {lambda}, and {iota}) and cytoplasmic HMGB1 were observed in HCT116 cells. We further identified the most critical PKC isotype that regulates HMGB1 secretion is PKC-{zeta} by using PKC inhibitors and siRNA experiments. The serine residues at S39, S53 and S181 of HMGB1 were related to enhancing HMGB1 secretion. We also demonstrated overexpression and activation of PKC-{zeta} in colon cancer tissues. Our findings suggest that PKC-{zeta} is involved in the phosphorylation of HMGB1, and the phosphorylation of specific serine residues in the nuclear localization signal regions is related to enhanced HMGB1 secretion in colon cancer cells.

High mobility group box1 (HMGB1) in relation to cutaneous inflammation in systemic lupus erythematosus (SLE)

NARCIS (Netherlands)

Abdulahad, D.A.; Westra, J.; Reefman, E.; Zuidersma, E.; Bijzet, J.; Limburg, P.C.; Kallenberg, C.G.M.; Bijl, M.

2013-01-01

Photosensitivity is characteristic of systemic lupus erythematosus (SLE). Upon ultraviolet B (UVB) exposure, patients develop inflammatory skin lesions in the vicinity of sunburn cells (SBCs). High mobility group box 1 (HMGB1) is released from apoptotic and activated cells and exerts inflammatory

RAGE-Specific Inhibitor FPS-ZM1 Attenuates AGEs-Induced Neuroinflammation and Oxidative Stress in Rat Primary Microglia.

Science.gov (United States)

Shen, Chao; Ma, Yingjuan; Zeng, Ziling; Yin, Qingqing; Hong, Yan; Hou, Xunyao; Liu, Xueping

2017-10-01

Advanced glycation end products (AGEs) enhance microglial activation and intensify the inflammatory response and oxidative stress in the brain. This process may occur due to direct cytotoxicity or interacting with AGEs receptors (RAGE), which are expressed on the surface of microglia. FPS-ZM1 is a high-affinity but nontoxic RAGE-specific inhibitor that has been recently shown to attenuate the Aβ-induced inflammatory response by blocking the ligation of Aβ to RAGE. In this study, we further investigated the effect of FPS-ZM1 on the AGEs/RAGE interaction and downstream elevation of neuroinflammation and oxidative stress in primary microglia cells. The results suggested that FPS-ZM1 significantly suppressed AGEs-induced RAGE overexpression, RAGE-dependent microglial activation, nuclear translocation of nuclear factor kappaB p65 (NF-κB p65), and the expression of downstream inflammatory mediators such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), cyclooxygenase 2 (COX-2)/prostaglandin E2 (PGE2) and inducible nitric oxide synthase (iNOS)/nitric oxide (NO). Furthermore, FPS-ZM1 attenuated AGEs-stimulated NADPH oxidase (NOX) activation and reactive oxygen species (ROS) expression. Finally, FPS-ZM1 elevated the levels of transcription factors nuclear-factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1), as well as decreased antioxidant capacity and increased production of oxidative species. Our results suggest that FPS-ZM1 may be neuroprotective through attenuating microglial activation, oxidative stress and inflammation by blocking RAGE.

AGE-RAGE Stress, Stressors, and Antistressors in Health and Disease.

Science.gov (United States)

Prasad, Kailash; Mishra, Manish

2018-03-01

Adverse effects of advanced glycation end-products (AGEs) on the tissues are through nonreceptor- and receptor-mediated mechanisms. In the receptor-mediated mechanism, interaction of AGEs with its cell-bound receptor of AGE (RAGE) increases generation of oxygen radicals, activates nuclear factor-kappa B, and increases expression and release of pro-inflammatory cytokines resulting in the cellular damage. The deleterious effects of AGE and AGE-RAGE interaction are coined as "AGE-RAGE stress." The body is equipped with defense mechanisms to counteract the adverse effects of AGE and RAGE through endogenous enzymatic (glyoxalase 1, glyoxalase 2) and AGE receptor-mediated (AGER1, AGER2) degradation of AGE, and through elevation of soluble receptor of AGE (sRAGE). Exogenous defense mechanisms include reduction in consumption of AGE, prevention of AGE formation, and downregulation of RAGE expression. We have coined AGE and RAGE as "stressors" and the defense mechanisms as "anti-stressors." AGE-RAGE stress is defined as a shift in the balance between stressors and antistressors in the favor of stressors. Measurements of stressors or antistressors alone would not assess AGE-RAGE stress. For true assessment of AGE-RAGE stress, the equation should include all the stressors and antistressors. The equation for AGE-RAGE stress, therefore, would be the ratio of AGE + RAGE/sRAGE + glyoxalase1 + glyoxalase 2 + AGER1 +AGER2. This is, however, not practical in patients. AGE-RAGE stress may be assessed simply by the ratio of AGE/sRAGE. A high ratio of AGE/sRAGE indicates a relative shift in stressors from antistressors, suggesting the presence of AGE-RAGE stress, resulting in tissue damage, initiation, and progression of the diseases and their complications.

Redox-sensitive structural change in the A-domain of HMGB1 and its implication for the binding to cisplatin modified DNA

International Nuclear Information System (INIS)

Wang, Jing; Tochio, Naoya; Takeuchi, Aya; Uewaki, Jun-ichi; Kobayashi, Naohiro; Tate, Shin-ichi

2013-01-01

Highlights: •The structure of the oxidized A-domain of human HMGB1 was solved. •Phe38 ring was flipped in the oxidized structure from that in the reduced form. •The flipped ring disables the intercalation into the cisplatinated lesions. •The functionally relevant redox-dependent structural change was described. -- Abstract: HMGB1 (high-mobility group B1) is a ubiquitously expressed bifunctional protein that acts as a nuclear protein in cells and also as an inflammatory mediator in the extracellular space. HMGB1 changes its functions according to the redox states in both intra- and extra-cellular environments. Two cysteines, Cys23 and Cys45, in the A-domain of HMGB1 form a disulfide bond under oxidative conditions. The A-domain with the disulfide bond shows reduced affinity to cisplatin modified DNA. We have solved the oxidized A-domain structure by NMR. In the structure, Phe38 has a flipped ring orientation from that found in the reduced form; the phenyl ring in the reduced form intercalates into the platinated lesion in DNA. The phenyl ring orientation in the oxidized form is stabilized through intramolecular hydrophobic contacts. The reorientation of the Phe38 ring by the disulfide bond in the A-domain may explain the reduced HMGB1 binding affinity towards cisplatinated DNA

Pentamidine blocks the interaction between mutant S100A5 and RAGE V domain and inhibits the RAGE signaling pathway

Energy Technology Data Exchange (ETDEWEB)

Cho, Ching Chang, E-mail: ccjwo@yahoo.com.tw [Department of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Chou, Ruey Hwang, E-mail: rhchou@mail.cmu.edu.tw [Graduate Institute of Cancer Biology and Center for Molecular Medicine, China Medical University, No.91, Hsueh-Shih Road, Taichung 40402, Taiwan (China); Yu, Chin, E-mail: cyu.nthu@gmail.com [Department of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China)

2016-08-19

The human S100 protein family contains small, dimeric and acidic proteins that contain two EF-hand motifs and bind calcium. When S100A5 binds calcium, its conformation changes and promotes interaction with the target protein. The extracellular domain of RAGE (Receptor of Advanced Glycation End products) contain three domains: C1, C2 and V. The RAGE V domain is the target protein of S100A5 that promotes cell survival, growth and differentiation by activating several signaling pathways. Pentamidine is an apoptotic and antiparasitic drug that is used to treat or prevent pneumonia. Here, we found that pentamidine interacts with S100A5 using HSQC titration. We elucidated the interactions of S100A5 with RAGE V domain and pentamidine using fluorescence and NMR spectroscopy. We generated two binary models—the S100A5-RAGE V domain and S100A5-Pentamidine complex—and then observed that the pentamidine and RAGE V domain share a similar binding region in mS100A5. We also used the WST-1 assay to investigate the bioactivity of S100A5, RAGE V domain and pentamidine. These results indicated that pentamidine blocks the binding between S100A5 and RAGE V domain. This finding is useful for the development of new anti-proliferation drugs. - Highlights: • The interaction between mS100A5–RAGE V was investigated by fluorescence spectroscopy. • The interfacial residues on mS100A5–RAGE V and mS100A5–pentamidine contact surface were mapped by {sup 1}H-{sup 15}N HSQC experiments. • mS100A5–RAGE V and mS100A5–pentamidine complex models were generated from NMR restraints using HADDOCK program. • The bioactivity of the mS100A5–RAGE V and mS100A5–pentamidine complex was studied using WST-1 assay.

Protection against RAGE-mediated neuronal cell death by sRAGE-secreting human mesenchymal stem cells in 5xFAD transgenic mouse model.

Science.gov (United States)

Son, Myeongjoo; Oh, Seyeon; Park, Hyunjin; Ahn, Hyosang; Choi, Junwon; Kim, Hyungho; Lee, Hye Sun; Lee, Sojung; Park, Hye-Jeong; Kim, Seung U; Lee, Bonghee; Byun, Kyunghee

2017-11-01

Alzheimer's disease (AD), which is the most commonly encountered neurodegenerative disease, causes synaptic dysfunction and neuronal loss due to various pathological processes that include tau abnormality and amyloid beta (Aβ) accumulation. Aβ stimulates the secretion and the synthesis of Receptor for Advanced Glycation End products (RAGE) ligand by activating microglial cells, and has been reported to cause neuronal cell death in Aβ 1-42 treated rats and in mice with neurotoxin-induced Parkinson's disease. The soluble form of RAGE (sRAGE) is known to reduce inflammation, and to decrease microglial cell activation and Aβ deposition, and thus, it protects from neuronal cell death in AD. However, sRAGE protein has too a short half-life for therapeutic purposes. We developed sRAGE-secreting umbilical cord derived mesenchymal stem cells (sRAGE-MSCs) to enhance the inhibitory effects of sRAGE on Aβ deposition and to reduce the secretion and synthesis of RAGE ligands in 5xFAD mice. In addition, these cells improved the viability of injected MSCs, and enhanced the protective effects of sRAGE by inhibiting the binding of RAGE and RAGE ligands in 5xFAD mice. These findings suggest sRAGE protein from sRAGE-MSCs has better protection against neuronal cell death than sRAGE protein or single MSC treatment by inhibiting the RAGE cell death cascade and RAGE-induce inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.

Metformin suppresses CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating aryl hydrocarbon receptor expression

Energy Technology Data Exchange (ETDEWEB)

Do, Minh Truong; Kim, Hyung Gyun; Tran, Thi Thu Phuong; Khanal, Tilak; Choi, Jae Ho [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of); Chung, Young Chul [Department of Food Science and Culinary, International University of Korea, Jinju (Korea, Republic of); Jeong, Tae Cheon, E-mail: taecheon@ynu.ac.kr [College of Pharmacy, Yeungnam University, Gyeongsan (Korea, Republic of); Jeong, Hye Gwang, E-mail: hgjeong@cnu.ac.kr [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of)

2014-10-01

Induction of cytochrome P450 (CYP) 1A1 and CYP1B1 by environmental xenobiotic chemicals or endogenous ligands through the activation of the aryl hydrocarbon receptor (AhR) has been implicated in a variety of cellular processes related to cancer, such as transformation and tumorigenesis. Here, we investigated the effects of the anti-diabetes drug metformin on expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and inducible conditions. Our results indicated that metformin down-regulated the expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced conditions. Down-regulation of AhR expression was required for metformin-mediated decreases in CYP1A1 and CYP1B1 expression, and the metformin-mediated CYP1A1 and CYP1B1 reduction is irrelevant to estrogen receptor α (ERα) signaling. Furthermore, we found that metformin markedly down-regulated Sp1 protein levels in breast cancer cells. The use of genetic and pharmacological tools revealed that metformin-mediated down-regulation of AhR expression was mediated through the reduction of Sp1 protein. Metformin inhibited endogenous AhR ligand-induced CYP1A1 and CYP1B1 expression by suppressing tryptophan-2,3-dioxygenase (TDO) expression in MCF-7 cells. Finally, metformin inhibits TDO expression through a down-regulation of Sp1 and glucocorticoid receptor (GR) protein levels. Our findings demonstrate that metformin reduces CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating AhR signaling. Metformin would be able to act as a potential chemopreventive agent against CYP1A1 and CYP1B1-mediated carcinogenesis and development of cancer. - Graphical abstract: Schematic of the CYP1A1 and CYP1B1 gene regulation by metformin. - Highlights: • Metformin inhibits CYP1A1 and CYP1B1 expression. • Metformin down-regulates the AhR signaling. • Metformin reduces Sp1 protein expression. • Metformin suppresses TDO expression.

Metformin suppresses CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating aryl hydrocarbon receptor expression

International Nuclear Information System (INIS)

Do, Minh Truong; Kim, Hyung Gyun; Tran, Thi Thu Phuong; Khanal, Tilak; Choi, Jae Ho; Chung, Young Chul; Jeong, Tae Cheon; Jeong, Hye Gwang

2014-01-01

Induction of cytochrome P450 (CYP) 1A1 and CYP1B1 by environmental xenobiotic chemicals or endogenous ligands through the activation of the aryl hydrocarbon receptor (AhR) has been implicated in a variety of cellular processes related to cancer, such as transformation and tumorigenesis. Here, we investigated the effects of the anti-diabetes drug metformin on expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and inducible conditions. Our results indicated that metformin down-regulated the expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced conditions. Down-regulation of AhR expression was required for metformin-mediated decreases in CYP1A1 and CYP1B1 expression, and the metformin-mediated CYP1A1 and CYP1B1 reduction is irrelevant to estrogen receptor α (ERα) signaling. Furthermore, we found that metformin markedly down-regulated Sp1 protein levels in breast cancer cells. The use of genetic and pharmacological tools revealed that metformin-mediated down-regulation of AhR expression was mediated through the reduction of Sp1 protein. Metformin inhibited endogenous AhR ligand-induced CYP1A1 and CYP1B1 expression by suppressing tryptophan-2,3-dioxygenase (TDO) expression in MCF-7 cells. Finally, metformin inhibits TDO expression through a down-regulation of Sp1 and glucocorticoid receptor (GR) protein levels. Our findings demonstrate that metformin reduces CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating AhR signaling. Metformin would be able to act as a potential chemopreventive agent against CYP1A1 and CYP1B1-mediated carcinogenesis and development of cancer. - Graphical abstract: Schematic of the CYP1A1 and CYP1B1 gene regulation by metformin. - Highlights: • Metformin inhibits CYP1A1 and CYP1B1 expression. • Metformin down-regulates the AhR signaling. • Metformin reduces Sp1 protein expression. • Metformin suppresses TDO expression

Anti-HMGB1 Antibodies and Alpha-7 Agonists as Experimental Therapeutics as BW Countermeasures

National Research Council Canada - National Science Library

Tracey, Kevin

2006-01-01

.... We originally identified a cytokine role for HMGB1, a protein known previously as a transcription factor, and have since focused our efforts on studying the role of this mediator in the pathogenesis of severe sepsis...

Protein Phosphatase 1 Down Regulates ZYG-1 Levels to Limit Centriole Duplication.

Directory of Open Access Journals (Sweden)

Nina Peel

2017-01-01

Full Text Available In humans perturbations of centriole number are associated with tumorigenesis and microcephaly, therefore appropriate regulation of centriole duplication is critical. The C. elegans homolog of Plk4, ZYG-1, is required for centriole duplication, but our understanding of how ZYG-1 levels are regulated remains incomplete. We have identified the two PP1 orthologs, GSP-1 and GSP-2, and their regulators I-2SZY-2 and SDS-22 as key regulators of ZYG-1 protein levels. We find that down-regulation of PP1 activity either directly, or by mutation of szy-2 or sds-22 can rescue the loss of centriole duplication associated with a zyg-1 hypomorphic allele. Suppression is achieved through an increase in ZYG-1 levels, and our data indicate that PP1 normally regulates ZYG-1 through a post-translational mechanism. While moderate inhibition of PP1 activity can restore centriole duplication to a zyg-1 mutant, strong inhibition of PP1 in a wild-type background leads to centriole amplification via the production of more than one daughter centriole. Our results thus define a new pathway that limits the number of daughter centrioles produced each cycle.

Cloning, characterisation, and comparative quantitative expression analyses of receptor for advanced glycation end products (RAGE) transcript forms.

Science.gov (United States)

Sterenczak, Katharina A; Willenbrock, Saskia; Barann, Matthias; Klemke, Markus; Soller, Jan T; Eberle, Nina; Nolte, Ingo; Bullerdiek, Jörn; Murua Escobar, Hugo

2009-04-01

RAGE is a member of the immunoglobulin superfamily of cell surface molecules playing key roles in pathophysiological processes, e.g. immune/inflammatory disorders, Alzheimer's disease, diabetic arteriosclerosis and tumourigenesis. In humans 19 naturally occurring RAGE splicing variants resulting in either N-terminally or C-terminally truncated proteins were identified and are lately discussed as mechanisms for receptor regulation. Accordingly, deregulation of sRAGE levels has been associated with several diseases e.g. Alzheimer's disease, Type 1 diabetes, and rheumatoid arthritis. Administration of recombinant sRAGE to animal models of cancer blocked tumour growth successfully. In spite of its obvious relationship to cancer and metastasis data focusing sRAGE deregulation and tumours is rare. In this study we screened a set of tumours, healthy tissues and various cancer cell lines for RAGE splicing variants and analysed their structure. Additionally, we analysed the ratio of the mainly found transcript variants using quantitative Real-Time PCR. In total we characterised 24 previously not described canine and 4 human RAGE splicing variants, analysed their structure, classified their characteristics, and derived their respective protein forms. Interestingly, the healthy and the neoplastic tissue samples showed in majority RAGE transcripts coding for the complete receptor and transcripts showing insertions of intron 1.

MicroRNA-129-5p inhibits the development of autoimmune encephalomyelitis-related epilepsy by targeting HMGB1 through the TLR4/NF-kB signaling pathway.

Science.gov (United States)

Liu, Ai-Hua; Wu, Ya-Ting; Wang, Yu-Ping

2017-06-01

The study aimed to explore the effects of microRNA-129-5p (miR-129-5p) on the development of autoimmune encephalomyelitis (AE)-related epilepsy by targeting HMGB1 through the TLR4/NF-kB signaling pathway in a rat model. AE-related epilepsy models were established. Sprague-Dawley (SD) rats were randomly divided into control, model, miR-129-5p mimics, miR-129-5p inhibitor, HMGB1 shRNA, TLR4/NF-kB (TLR4/NF-kB signaling pathway was inhibited) and miR-129-5p mimics+HMGB1 shRNA groups respectively. Latency to a first epilepsy seizure attack was recorded. Neuronal injuries in the hippocampus regions were detected using HE, Nissl and FJB staining methods 24h following model establishment. Microglial cells were detected by OX-42 immunohistochemistry. Expressions of miR-129-5p, HMGB1 and TLR4/NF-kB signaling pathway-related proteins were detected by qRT-PCR. Protein expressions of HMGB1 and TLR4/NF-kB signaling pathway-related proteins were detected by Western blotting. Dual luciferase reporter gene assay showed that miR-129-5p was negatively targeting HMGB1. Neurons of hippocampal tissues in rats were heavily injured by an injection of lithium chloride. Compared with the model and control groups, neuronal injury of the hippocampus and AE-related epilepsy decreased and microglial cells increased in the miR-129-5p mimics, HMGB1 shRNA and TLR4/NF-kB groups; however, in the miR-129-5p inhibitor group, miR-129-5p expression decreased, HMGB1 expression increased, TLR4/NF-kB signaling pathway was activated, latency to a first epilepsy seizure attack was shortened, and neuronal injury increased. This study provides evidence that miR-129-5p inhibits the development of AE-related epilepsy by suppressing HMGB1 expression and inhibiting TLR4/NF-kB signaling pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective effect of glycyrrhizin, a direct HMGB1 inhibitor, on focal cerebral ischemia/reperfusion-induced inflammation, oxidative stress, and apoptosis in rats.

Directory of Open Access Journals (Sweden)

Gu Gong

Full Text Available AIM: Glycyrrhizin (GL has been reported to protect against ischemia and reperfusion (I/R-induced injury by inhibiting the cytokine activity of high mobility group box 1 (HMGB1. In the present study, the protective effects of GL against I/R injury, as well as the related molecular mechanisms, were investigated in rat brains. METHODS: Focal cerebral I/R injury was induced by intraluminal filamentous occlusion of the middle cerebral artery (MCA in Male Sprague-Dawley rats. GL alone or GL and rHMGB1 were administered intravenously at the time of reperfusion. Serum levels of HMGB1 and inflammatory mediators were quantified via enzyme-linked immunosorbent assay (ELISA. Histopathological examination, immunofluorescence, RT-PCR and western blotting analyses were performed to investigate the protective and anti-apoptotic effects and related molecular mechanisms of GL against I/R injury in rat brains. RESULTS: Pre-treatment with GL significantly reduced infarct volume and improved the accompanying neurological deficits in locomotor function. The release of HMGB1 from the cerebral cortex into the serum was inhibited by GL administration. Moreover, pre-treatment with GL alleviated apoptotic injury resulting from cerebral I/R through the inhibition of cytochrome C release and caspase 3 activity. The expression levels of inflammation- and oxidative stress-related molecules including TNF-α, iNOS, IL-1β, and IL-6, which were over-expressed in I/R, were decreased by GL. P38 and P-JNK signalling were involved in this process. All of the protective effects of GL could be reversed by rHMGB1 administration. CONCLUSIONS: GL has a protective effect on ischemia-reperfusion injury in rat brains through the inhibition of inflammation, oxidative stress and apoptotic injury by antagonising the cytokine activity of HMGB1.

Expression and significance of HMGB1, TLR4 and NF-κB p65 in human epidermal tumors

International Nuclear Information System (INIS)

Weng, Hui; Deng, Yunhua; Xie, Yuyan; Liu, Hongbo; Gong, Feili

2013-01-01

High mobility group protein box 1 (HMGB1) is a DNA binding protein located in nucleus. It is released into extracellular fluid where it acts as a novel proinflammatory cytokine which interacts with Toll like receptor 4 (TLR4) to activate nuclear factor-κB (NF-κB). This sequence of events is involved in tumor growth and progression. However, the effects of HMGB1, TLR4 and NF-κB on epidermal tumors remain unclear. Human epidermal tumor specimens were obtained from 96 patients. Immunohistochemistry was used to detect expression of HMGB1, TLR4 and NF-κB p65 in human epidermal tumor and normal skin specimens. Western blot analysis was used to detect the expression of NF-κB p65 in epithelial cell nuclei in human epidermal tumor and normal tissues. Immunohistochemistry and western blot analysis indicated a progressive but statistically significant increase in p65 expression in epithelial nuclei in benign seborrheic keratosis (SK), precancerous lesions (PCL), low malignancy basal cell carcinoma (BCC) and high malignancy squamous cell carcinoma (SCC) (P <0.01). The level of extracellular HMGB1 in SK was significantly higher than in normal skin (NS) (P <0.01), and was higher than in SCC but without statistical significance. The level of TLR4 on epithelial membranes of SCC cells was significantly higher than in SK, PCL, BCC and NS (P <0.01). There was a significant positive correlation between p65 expression in the epithelial nuclei and TLR4 expression on the epithelial cell membranes (r = 0.3212, P <0.01). These findings indicate that inflammation is intensified in parallel with increasing malignancy. They also indicate that the TLR4 signaling pathway, rather than HMGB1, may be the principal mediator of inflammation in high-grade malignant epidermal tumors. Combined detection of p65 in the epithelial nuclei and TLR4 on the epithelial membranes may assist the accurate diagnosis of malignant epidermal tumors

Elevated levels of von Willebrand factor and high mobility group box 1 (HMGB1) are associated with disease severity and clinical outcome of scrub typhus.

Science.gov (United States)

Chen, Hongliu; Ning, Zong; Qiu, Ying; Liao, Yuanli; Chang, Haihua; Ai, Yuanyuan; Wei, Yinghua; Deng, Yiming; Shen, Ying

2017-08-01

This study aimed to investigate whether von Willebrand factor (vWF) and high mobility group box 1 (HMGB1) are associated with the severity and clinical outcome of scrub typhus and to seek novel biomarkers for surveillance and prediction of the prognosis of this infection. Serum concentrations of vWF and HMGB1 were measured twice by ELISA for scrub typhus patients (n=103), once prior to doxycycline therapy and then on day 7 of doxycycline therapy; concentrations were measured once for healthy controls (n=32). Among the total 103 patients enrolled, 38 had disease complicated by multiple organ dysfunction syndrome (MODS). Serum concentrations of vWF and HMGB1 were significantly higher in all the patients than in the healthy controls, both prior to doxycycline treatment and on day 7 of doxycycline treatment (pscrub typhus (area under the curve (AUC)=0.864, p=0.001, and AUC=0.862, p=0.001, respectively). Elevated levels of vWF and HMGB1 are associated with the severity and clinical outcome of scrub typhus. These represent possible new biomarkers for use in the assessment and prognostic prediction of this infection. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in high glucose treated human mesangial cells

International Nuclear Information System (INIS)

Li, Yang; Hu, Fang; Xue, Meng; Jia, Yi-Jie; Zheng, Zong-Ji; Wang, Ling; Guan, Mei-Ping; Xue, Yao-Ming

2017-01-01

Diabetic kidney disease (DKD) has become the leading cause of end-stage renal disease worldwide and is associated with glomerular mesangial cell (MC) proliferation and excessive extracellular matrix (ECM) production. Klotho can attenuate renal fibrosis in part by inhibiting TGF-β1/Smad3 signaling in DKD. Early growth response factor 1 (Egr-1) has been shown to play a key role in renal fibrosis in part by facilitating the formation of a positive feedback loop involving TGF-β1. However, whether Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in DKD is unclear. In the present study, we assessed human MCs that were incubated under high-glucose conditions to mimic diabetes. Then, we transfected the cells with Klotho plasmid or siRNA to overexpress or knock down Klotho gene and protein expression. Klotho, Egr-1, fibronectin (FN), collagen type I (Col I), Smad3 and phosphorylated Smad3 (p-Smad3) gene and protein expression levels were determined by RT-qPCR and western blotting respectively. High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. pcDNA3.1-Klotho transfection-mediated Klotho overexpression down-regulated Egr-1, FN and Col I expression and the p-Smad3/Smad3 ratio in human MCs. Conversely, siRNA-mediated Klotho silencing up-regulated Egr-1, FN, and Col I expression and the p-Smad3/Smad3 ratio. Moreover, the effects of si-Klotho on Egr-1 expression were abolished by the TGF-β1 inhibitor SB-431542. Klotho overexpression can prevent mesangial ECM production in high-glucose-treated human MCs, an effect that has been partially attributed to Egr-1 down-regulation facilitated by TGF-β1/Smad3 signaling inhibition. - Highlights: • High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. • Klotho overexpression down-regulated Egr-1 and prevented mesangial ECM production in high-glucose-treated human MCs. • Klotho down-regulated Egr-1 by inhibiting

The cardiac copper chaperone proteins Sco1 and CCS are up-regulated, but Cox 1 and Cox4 are down-regulated, by copper deficiency.

Science.gov (United States)

Getz, Jean; Lin, Dingbo; Medeiros, Denis M

2011-10-01

Copper is ferried in a cell complexed to chaperone proteins, and in the heart much copper is required for cytochrome c oxidase (Cox). It is not completely understood how copper status affects the levels of these proteins. Here we determined if dietary copper deficiency could up- or down-regulate select copper chaperone proteins and Cox subunits 1 and 4 in cardiac tissue of rats. Sixteen weanling male Long-Evans rats were randomized into treatment groups, one group receiving a copper-deficient diet (CCS, Sco1, Ctr1, Cox17, Cox1, and Cox4 by SDS-PAGE and Western blotting. No changes were observed in the concentrations of CTR1 and Cox17 between copper-adequate and copper-deficient rats. CCS and Sco1 were up-regulated and Cox1 and Cox4 were both down-regulated as a result of copper deficiency. These data suggest that select chaperone proteins and may be up-regulated, and Cox1 and 4 down-regulated, by a dietary copper deficiency, whereas others appear not to be affected by copper status.

Inhibition of HMGB1 reduces rat spinal cord astrocytic swelling and AQP4 expression after oxygen-glucose deprivation and reoxygenation via TLR4 and NF-κB signaling in an IL-6-dependent manner.

Science.gov (United States)

Sun, Lin; Li, Man; Ma, Xun; Feng, Haoyu; Song, Junlai; Lv, Cong; He, Yajun

2017-11-25

Spinal cord astrocyte swelling is an important component to spinal cord edema and is associated with poor functional recovery as well as therapeutic resistance after spinal cord injury (SCI). High mobility group box-1 (HMGB1) is a mediator of inflammatory responses in the central nervous system and plays a critical role after SCI. Given this, we sought to identify both the role and underlying mechanisms of HMGB1 in cellular swelling and aquaporin 4 (AQP4) expression in cultured rat spinal cord astrocytes after oxygen-glucose deprivation/reoxygenation (OGD/R). The post-natal day 1-2 Sprague-Dawley rat spinal cord astrocytes were cultured in vitro, and the OGD/R model was induced. We first investigated the effects of OGD/R on spinal cord astrocytic swelling and HMGB1 and AQP4 expression, as well as HMGB1 release. We then studied the effects of HMGB1 inhibition on cellular swelling, HMGB1 and AQP4 expression, and HMGB1 release. The roles of both toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway and interleukin-6 (IL-6) in reducing cellular swelling resulting from HMGB1 inhibition in spinal cord astrocytes after OGD/R were studied. Intergroup data were compared using one-way analysis of variance (ANOVA) followed by Dunnett's test. The OGD/R increased spinal cord astrocytic swelling and HMGB1 and AQP4 expression, as well as HMGB1 release. Inhibition of HMGB1 using either HMGB1 shRNA or ethyl pyruvate resulted in reduced cellular volume, mitochondrial and endoplasmic reticulum swelling, and lysosome number and decreased upregulation of both HMGB1 and AQP4 in spinal cord astrocytes, as well as HMGB1 release. The HMGB1 effects on spinal cord astrocytic swelling and AQP4 upregulation after OGD/R were mediated-at least in part-via activation of TLR4, myeloid differentiation primary response gene 88 (MyD88), and NF-κB. These activation effects can be repressed by TLR4 inhibition using CLI-095 or C34, or by NF-κB inhibition using BAY 11

Protein kinase B/Akt1 inhibits autophagy by down-regulating UVRAG expression

Energy Technology Data Exchange (ETDEWEB)

Yang, Wonseok; Ju, Ji-hyun; Lee, Kyung-min; Nam, KeeSoo; Oh, Sunhwa [Department of Life Science, College of Natural Science, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Shin, Incheol, E-mail: incheol@hanyang.ac.kr [Department of Life Science, College of Natural Science, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)

2013-02-01

Autophagy, or autophagocytosis, is a selective intracellular degradative process involving the cell's own lysosomal apparatus. An essential component in cell development, homeostasis, repair and resistance to stress, autophagy may result in either cell death or survival. The targeted region of the cell is sequestered within a membrane structure, the autophagosome, for regulation of the catabolic process. A key factor in both autophagosome formation and autophagosome maturation is a protein encoded by the ultraviolet irradiation resistance-associated gene (UVRAG). Conversely, the serine/threonine-specific protein kinase B (PKB, also known as Akt), which regulates survival in various cancers, inhibits autophagy through mTOR activation. We found that Akt1 may also directly inhibit autophagy by down-regulating UVRAG both in a 293T transient transfection system and breast cancer cells stably expressing Akt1. The UVRAG with mutations at putative Akt1-phosphorylation sites were still inhibited by Akt1, and dominant-negative Akt1 also inhibited UVRAG expression, suggesting that Akt1 down-regulates UVRAG by a kinase activity-independent mechanism. We showed that Akt1 overexpression in MDA-MB-231 breast cancer cells down-regulated UVRAG transcription. Cells over-expressing Akt1 were more resistant than control cells to ultraviolet light-induced autophagy and exhibited the associated reduction in cell viability. Levels of the autophagosome indicator protein LC3B-II and mRFP-GFP-LC3 were reduced in cells that over-expressing Akt1. Inhibiting Akt1 by siRNA or reintroducing UVRAG gene rescued the level of LC3B-II in UV-irradiation. Altogether, these data suggest that Akt1 may inhibit autophagy by decreasing UVRAG expression, which also sensitizes cancer cells to UV irradiation.

"Uproar, bulk, rage, suffocation, effort unceasing, frenzied and vain": Beckett's Transports of Rage.

Science.gov (United States)

Smith, Russell

2016-06-01

In a 1961 interview, Beckett warded off philosophical interpretations of his work: 'I'm no intellectual. All I am is feeling'. Despite the emotional intensity of Beckett's post-war writing, Beckett criticism has tended to ignore this claim, preferring the kinds of philosophical readings that Beckett here rejects. In particular, Beckett criticism underestimates the element of rage in his work. This paper argues that Beckett's post-war breakthrough is enabled by a radical reconsideration of the nature of feeling and of rage in particular. It involves the rejection of the idea of rage as pathological and the embrace of a positive conception of rage as drive or compulsion, a locus of energy and even pleasure.This paper reads the 'Moran' section of Molloy as a kind of 'rage fable', drawing on the ancient Greek concept of thymos, of anger as a virtue. It draws on Alfred Adler's theory of the 'masculine protest', with which Beckett was familiar from his extensive note-taking on Adler in 1934-5, and Sianne Ngai's discussion of the distinction between irritation and rage. According to this reading, Moran's report charts a narrative of thymotic liberation from the irritations of servitude, prefiguring the Unnamable's abandonment to impersonal affective intensities. It ends by suggesting that the prose of the Trilogy might be better understood, not as a 'syntax of weakness' but as a 'syntax of rage', a stylistic correlative of the imperious drive of thymos. We might then begin to understand the Trilogy as the epic of a heroic, impersonal, implacable and liberated rage.

Low-molecular weight fractions of Japanese soy sauce act as a RAGE antagonist via inhibition of RAGE trafficking to lipid rafts.

Science.gov (United States)

Munesue, Seiichi; Yamamoto, Yasuhiko; Urushihara, Ryouta; Inomata, Kouhei; Saito, Hidehito; Motoyoshi, So; Watanabe, Takuo; Yonekura, Hideto; Yamamoto, Hiroshi

2013-12-01

Advanced glycation end-products (AGE) have been implicated in aging and the pathogenesis of diabetic complications, inflammation, Alzheimer's disease, and cancer. AGE engage the cell surface receptor for AGE (RAGE), which in turn elicits intracellular signaling, leading to activation of NF-κB to cause deterioration of tissue homeostasis. AGE are not only formed within our bodies but are also derived from foods, endowing them with flavor. In the present study, we assessed the agonistic/antagonistic effects of food-derived AGE on RAGE signaling in a reporter assay system and found that low-molecular weight AGE can antagonize the action of AGE-BSA. Foods tested were Japanese soy sauce, coffee, cola, and red wine, all of which showed fluorescence characteristics of AGE. Soy sauce and coffee contained N(ε)-carboxymethyl-lysine (CML). Soy sauce, coffee, and red wine inhibited the RAGE ligand-induced activation of NF-κB, whereas cola had no effect on the ligand induction of NF-κB. The liquids were then fractionated into high-molecular weight (HMW) fractions and low-molecular weight (LMW) fractions. Soy sauce-, coffee-, and red wine-derived LMW fractions consistently inhibited the RAGE ligand induction of NF-κB, whereas the HMW fractions of these foods activated RAGE signaling. Using the LMW fraction of soy sauce as a model food-derived RAGE antagonist, we performed a plate-binding assay and found that the soy sauce LMW fractions competitively inhibited AGE-RAGE association. Further, this fraction significantly reduced AGE-dependent monocyte chemoattractant protein-1 (MCP-1) secretion from murine peritoneal macrophages. The LMF from soy sauce suppressed the AGE-induced RAGE trafficking to lipid rafts. These results indicate that small components in some, if not all, foods antagonize RAGE signaling and could exhibit beneficial effects on RAGE-related diseases.

Insight into the mechanisms regulating immune homeostasis in health and disease.

Science.gov (United States)

Sirisinha, Stitaya

2011-03-01

Innate and adaptive immune systems consist of cells and molecules that work together in concert to fight against microbial infection and maintain homeostasis. Hosts encounter microbes / exogenous pathogen-associated molecular patterns (PAMPs) and endogenous damage-associated molecular patterns (DAMPs) all the time and they must have proper mechanisms to counteract the danger such that appropriate responses (e.g., degree of inflammation and types of mediators induced) can be mounted in different scenarios. Increasing numbers of endogenous danger signals of host origin are being identified including, for example, uric acid and cholesterol crystals, high mobility group box1 (HMGB1) protein, oxidized LDL, vesicans, heat shock proteins (HSPs) and self DNA. Many of these endogenous ligands have been shown to be associated with inflammation-related diseases like atherosclerosis, gout and type 2 diabetes. Several DAMPs appear to have the ability to interact with more than one receptor. We are now beginning to understand how the immune system can distinguish infection from endogenous ligands elaborated following cellular insults and tissue damage. Appropriate responses to maintain the homeostatic state in health and disease depend largely on the recognition and response to these stimuli by germline encoded pattern-recognition receptors (PRRs) present on both immune and non-immune cells. These receptors are, for example, Toll-like receptors (TLRs), C-type lectin receptors (CLRs) and cytosolic receptors (e.g., RLRs, NLRs and some intracellular DNA sensors). Atypical PRR "danger" receptors, like the receptor for advanced glycation end products (RAGE) and their ligands have been identified. A proper response to maintain homeostasis relies on specific negative regulators and regulatory pathways to dampen its response to tissue injury while maintaining the capacity to eliminate infection and induce proper tissue repair. Moreover, some PRRs (e.g., TLR2,TLR4 and NLRP3) and atypical

Ethanol extracts from Portulaca oleracea L. attenuated ischemia/reperfusion induced rat neural injury through inhibition of HMGB1 induced inflammation

Science.gov (United States)

Zheng, Chenggang; Liu, Chen; Wang, Wanyin; Tang, Gusheng; Dong, Liwei; Zhou, Juan; Zhong, Zhengrong

2016-01-01

It is well demonstrated that the high mobility group box 1 (HMGB1) mediated inflammation has been implicated as one of the important causes for brain damage induced by cerebral ischemia/reperfusion (I/R). In the present study, we assessed the neuro-protective and anti-inflammation effects of the ethanol extracts from Portulaca oleracea L. (EEPO) against cerebral I/R injury in the rat transient middle cerebral artery occlusion (tMCAO) model. Rats were administrated with their respective treatment for 7 days before the MCA occlusion. After that, rats were intraperitoneal injection with chloral hydrate and sacrificed by decapitation, then the serum and brain tissue were collected. The neurological deficit score, infarct size and brain edema were tested. The levels of serum cytokine as TNF-α, IL-1β, INF-γ, IL-6, and HMGB1 and LDH were detected. The protein level of tissue or nucleus HMGB1, IκB and p-p65 were tested, too. The results showed that pretreatment with EEPO significantly decreased the neurological deficit score, infarct size and brain edema. Moreover, EEPO decreased rat serum cytokine level and rat right cortices p-p65 and IκB protein level. In conclusion all these results suggested that pretreatment with EEFPO provided significant protection against cerebral I/R injury in rats might by virtue of its anti-inflammation property through inhibition of increase of neuleus HMGB1. PMID:27904702

Nifedipine, a calcium channel blocker, inhibits advanced glycation end product (AGE)-elicited mesangial cell damage by suppressing AGE receptor (RAGE) expression via peroxisome proliferator-activated receptor-gamma activation

International Nuclear Information System (INIS)

Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

2009-01-01

The interaction between advanced glycation end products (AGE) and their receptor RAGE mediates the progressive alteration in renal architecture and loss of renal function in diabetic nephropathy. Oxidative stress generation and inflammation also play a central role in diabetic nephropathy. This study investigated whether and how nifedipine, a calcium channel blocker (CCB), blocked the AGE-elicited mesangial cell damage in vitro. Nifedipine, but not amlodipine, a control CCB, down-regulated RAGE mRNA levels and subsequently reduced reactive oxygen species (ROS) generation in AGE-exposed mesangial cells. AGE increased mRNA levels of vascular cell adhesion molecule-1 (VCAM-1) and induced monocyte chemoattractant protein-1 (MCP-1) production in mesangial cells, both of which were prevented by the treatment with nifedipine, but not amlodipine. The beneficial effects of nifedipine on AGE-exposed mesangial cells were blocked by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPAR-γ). Although nifedipine did not affect expression levels of PPAR-γ, it increased the PPAR-γ transcriptional activity in mesangial cells. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-inflammatory agent against AGE by suppressing RAGE expression in cultured mesangial cells via PPAR-γ activation.

HMGB1 interacts with human topoisomerase IIalpha and stimulates its catalytic activity

Czech Academy of Sciences Publication Activity Database

Štros, Michal; Bačíková, Alena; Muselíková Polanská, Eva; Štokrová, Jitka; Strauss, F.

2007-01-01

Roč. 35, č. 15 (2007), s. 5001-5013 ISSN 0305-1048 R&D Projects: GA ČR(CZ) GA204/05/2031; GA AV ČR(CZ) IAA400040702 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702; CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : HMGB1 * DNA topoisomerase IIalpha * DNA repair Subject RIV: BO - Biophysics Impact factor: 6.954, year: 2007

Co-expression of nuclear and cytoplasmic HMGB1 is inversely associated with infiltration of CD45RO+ T cells and prognosis in patients with stage IIIB colon cancer

International Nuclear Information System (INIS)

Peng, Rui-Qing; Zeng, Yi-Xin; Zhang, Xiao-Shi; Wu, Xiao-Jun; Ding, Ya; Li, Chun-Yan; Yu, Xing-Juan; Zhang, Xing; Pan, Zhi-Zhong; Wan, De-Sen; Zheng, Li-Ming

2010-01-01

The intratumoral infiltration of T cells, especially memory T cells, is associated with a favorable prognosis in early colorectal cancers. However, the mechanism underlying this process remains elusive. This study examined whether high-mobility group box 1 (HMGB1), a damage-associated molecular pattern (DAMP) molecule, is involved in the infiltration of T cells and disease progression in locally advanced colon cancer. Seventy-two cases of pathologically-confirmed specimens were obtained from patients with stage IIIB (T3N1M0) colon cancer who underwent radical resection between January 1999 and May 2002 at the Cancer Center of Sun Yat-Sen University. The density of tumor-infiltrating lymphocytes (TILs) within the tumor tissue and the expression of HMGB1 in the cancer cells were examined via immunohistochemical analysis. The phenotype of CD45RO+ cells was confirmed using a flow cytometric assay. The association between HMGB1 expression, the density of TILs, and the 5-year survival rate were analyzed. The density of CD45RO+ T cells within the tumor was independently prognostic, although a higher density of CD3+ T cells was also associated with a favorable prognosis. More importantly, the expression of HMGB1 was observed in both the nucleus and the cytoplasm (co-expression pattern) in a subset of colon cancer tissues, whereas nuclear-only expression of HMGB1 (nuclear expression pattern) existed in most of the cancer tissues and normal mucosa. The co-expression pattern of HMGB1 in colon cancer cells was inversely associated with the infiltration of both CD3+ and CD45RO+ T cells and 5-year survival rates. This study revealed that the co-expression of HMGB1 is inversely associated with the infiltration of CD45RO+ T cells and prognosis in patients with stage IIIB colon cancer, indicating that the distribution patterns of HMGB1 might contribute to the progression of colon cancer via modulation of the local immune response

Signal Diversity of Receptor for Advanced Glycation End Products.

Science.gov (United States)

Sakaguchi, Masakiyo; Kinoshita, Rie; Putranto, Endy Widya; Ruma, I Made Winarsa; Sumardika, I Wayan; Youyi, Chen; Tomonobu, Naoko; Yamamoto, Ken-Ichi; Murata, Hitoshi

2017-12-01

The receptor for advanced glycation end products (RAGE) is involved in inflammatory pathogenesis. It functions as a receptor to multiple ligands such as AGEs, HMGB1 and S100 proteins, activating multiple intracellular signaling pathways with each ligand binding. The molecular events by which ligand-activated RAGE controls diverse signaling are not well understood, but some progress was made recently. Accumulating evidence revealed that RAGE has multiple binding partners within the cytoplasm and on the plasma membrane. It was first pointed out in 2008 that RAGE's cytoplasmic tail is able to recruit Diaphanous-1 (Dia-1), resulting in the acquisition of increased cellular motility through Rac1/Cdc42 activation. We also observed that within the cytosol, RAGE's cytoplasmic tail behaves similarly to a Toll-like receptor (TLR4)-TIR domain, interacting with TIRAP and MyD88 adaptor molecules that in turn activate multiple downstream signals. Subsequent studies demonstrated the presence of an alternative adaptor molecule, DAP10, on the plasma membrane. The coupling of RAGE with DAP10 is critical for enhancing the RAGE-mediated survival signal. Interestingly, RAGE interaction on the membrane was not restricted to DAP10 alone. The chemotactic G-protein-coupled receptors (GPCRs) formyl peptide receptors1 and 2 (FPR1 and FPR2) also interacted with RAGE on the plasma membrane. Binding interaction between leukotriene B4 receptor 1 (BLT1) and RAGE was also demonstrated. All of the interactions affected the RAGE signal polarity. These findings indicate that functional interactions between RAGE and various molecules within the cytoplasmic area or on the membrane area coordinately regulate multiple ligand-mediated RAGE responses, leading to typical cellular phenotypes in several pathological settings. Here we review RAGE's signaling diversity, to contribute to the understanding of the elaborate functions of RAGE in physiological and pathological contexts.

Reduced soluble receptor for advanced glycation end-products (sRAGE) scavenger capacity precedes pre-eclampsia in Type 1 diabetes

Science.gov (United States)

Yu, Y; Hanssen, KF; Kalyanaraman, V; Chirindel, A; Jenkins, AJ; Nankervis, AJ; Torjesen, PA; Scholz, H; Henriksen, T; Lorentzen, B; Garg, SK; Menard, MK; Hammad, SM; Scardo, JA; Stanley, JR; Wu, M; Basu, A; Aston, CE; Lyons, TJ

2014-01-01

Objective Increased advanced glycation end-products (AGEs) and their soluble receptors (sRAGE) have been implicated in the pathogenesis of pre-eclampsia (PE). However, this association has not been elucidated in pregnancies complicated by diabetes. We aimed to investigate the serum levels of these factors in pregnant women with Type 1 diabetes mellitus (T1DM), a condition associated with a four-fold increase in PE. Design Prospective study in women with T1DM at 12.2 ± 1.9, 21.6 ± 1.5 and 31.5 ± 1.7 weeks of gestation [mean ± standard deviation (SD); no overlap] before PE onset. Setting Antenatal clinics. Population Pregnant women with T1DM (n = 118; 26 developed PE) and healthy nondiabetic pregnant controls (n = 21). Methods Maternal serum levels of sRAGE (total circulating pool), Nε-(carboxymethyl)lysine (CML), hydroimidazolone (methylglyoxal-modified proteins) and total AGEs were measured by immunoassays. Main outcome measures Serum sRAGE and AGEs in pregnant women with T1DM who subsequently developed PE (DM PE+) versus those who remained normotensive (DM PE–). Results In DM PE+ versus DM PE–, sRAGE was significantly lower in the first and second trimesters, prior to the clinical manifestation of PE (P diabetes, parity and mean arterial pressure as covariates. Conclusions In the early stages of pregnancy, lower circulating sRAGE levels, and the ratio of sRAGE to AGEs, may be associated with the subsequent development of PE in women with T1DM. PMID:22900949

Leucine zipper, down regulated in cancer-1 gene expression in prostate cancer

OpenAIRE

Salemi, Michele; Barone, Nunziata; La Vignera, Sandro; Condorelli, Rosita A.; Recupero, Domenico; Galia, Antonio; Fraggetta, Filippo; Aiello, Anna Maria; Pepe, Pietro; Castiglione, Roberto; Vicari, Enzo; Calogero, Aldo E.

2016-01-01

Numerous genetic alterations have been implicated in the development of prostate cancer (PCa). DNA and protein microarrays have enabled the identification of genes associated with apoptosis, which is important in PCa development. Despite the molecular mechanisms are not entirely understood, inhibition of apoptosis is a critical pathophysiological factor that contributes to the onset and progression of PCa. Leucine zipper, down-regulated in cancer 1 (LDOC-1) is a known regulator of the nuclear...

Receptor for advanced glycation end products involved in lung ischemia reperfusion injury in cardiopulmonary bypass attenuated by controlled oxygen reperfusion in a canine model.

Science.gov (United States)

Rong, Jian; Ye, Sheng; Liang, Meng-ya; Chen, Guang-xian; Liu, Hai; Zhang, Jin-Xin; Wu, Zhong-kai

2013-01-01

Controlled oxygen reperfusion could protect the lung against ischemia-reperfusion injury in cardiopulmonary bypass (CPB) by downregulating high mobility group box 1 (HMGB1), a high affinity receptor of HMGB1. This study investigated the effect of controlled oxygen reperfusion on receptor for advanced glycation end products (RAGE) expression and its downstream effects on lung ischemia-reperfusion injury. Fourteen canines received CPB with 60 minutes of aortic clamping and cardioplegic arrest followed by 90 minutes of reperfusion. Animals were randomized to receive 80% FiO2 during the entire procedure (control group) or to a test group receiving a controlled oxygen reperfusion protocol. Pathologic changes in lung tissues, RAGE expression, serum interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were evaluated. The lung pathologic scores after 25 and 90 minutes of reperfusion were significantly lower in the test group compared with the control group (p RAGE expression, TNF-α, and IL-6 were downregulated by controlled oxygen treatment (p RAGE might be involved in the lung ischemia-reperfusion injury in canine model of CPB, which was downregulated by controlled oxygen reperfusion.

A Molecular Dynamics Study on RAGE-Aβ42 Interaction and the Influence of G82S RAGE Polymorphism on Aβ Interaction

Directory of Open Access Journals (Sweden)

Sreeram Krishnan

2015-12-01

Full Text Available Interaction of amyloid peptides (Aβ with receptor for advanced glycation end products (RAGE elicits an inflammatory response and augments Alzheimer's disease (AD pathology. The present study was aimed to analyse the interactions of different forms of Aβ42 peptide with ligand binding domain of normal and G82S RAGE and their possible consequences in AD pathology. The structures of RAGE ectodomain (3CJJ, monomeric forms of Aβ42 - 1IYT (apolar and 1Z0Q (polar and fibrillar (2BEG were obtained from PDB. The structure of G82 and S82 RAGE was generated using SWISS MODEL. SIFT and PolyPhen analysis was performed to predict the phenotypic and functional effect of the amino acid substitution. The G82 and S82 variant structures were simulated in GROMACS and the 10 lowest energy structures were docked with different forms of Aβ42 using CLUSPRO in antibody mode. The lowest energy docked structure was further simulated for 5 ns. The structures corresponding to 0-5 ns were taken and the amino acid interactions were generated using PDBSUM. SIFT analysis indicated that G82S SNP had a tolerating effect on the structure of protein but polyphen predicted a probable damaging effect. Highest binding score was obtained with 2BEG docked with both G82 RAGE (-375.84 ± 7.425 Kcal/mol and G82S variant (-391.09 ± 13.391 Kcal/mol indicating that the fibrillar form showed better interaction. Compared to G82 RAGE, the S82 variant showed better interaction to all three forms of Aβ42. The results of study indicate that RAGE interacted better with fibrillar form of Aβ42 peptide and G82S mutation enhanced the binding affinity of RAGE towards amyloid peptides leading to enhanced inflammatory response.

Cloning and characterization of the canine receptor for advanced glycation end products.

Science.gov (United States)

Murua Escobar, Hugo; Soller, Jan T; Sterenczak, Katharina A; Sperveslage, Jan D; Schlueter, Claudia; Burchardt, Birgit; Eberle, Nina; Fork, Melanie; Nimzyk, Rolf; Winkler, Susanne; Nolte, Ingo; Bullerdiek, Jörn

2006-03-15

Metastasis is one of the major problems when dealing with malignant neoplasias. Accordingly, the finding of molecular targets, which can be addressed to reduce tumour metastasising, will have significant impact on the development of new therapeutic approaches. Recently, the receptor for advanced glycation end products (RAGE)-high mobility group B1 (HMGB1) protein complex has been shown to have significant influence on invasiveness, growth and motility of tumour cells, which are essential characteristics required for metastatic behaviour. A set of in vitro and in vivo approaches showed that blocking of this complex resulted in drastic suppression of tumour cell growth. Due to the similarities of human and canine cancer the dog has joined the common rodent animal model for therapeutic and preclinical studies. However, complete characterisation of the protein complex is a precondition to a therapeutic approach based on the blocking of the RAGE-HMGB1 complex to spontaneously occurring tumours in dogs. We recently characterised the canine HMGB1 gene and protein completely. Here we present the complete characterisation of the canine RAGE gene including its 1384 bp mRNA, the 1215 bp protein coding sequence, the 2835 bp genomic structure, chromosomal localisation, gene expression pattern, and its 404 amino acid protein. Furthermore we compared the CDS of six different canine breeds and screened them for single nucleotide polymorphisms.

SAMHD1 is down regulated in lung cancer by methylation and inhibits tumor cell proliferation

International Nuclear Information System (INIS)

Wang, Jia-lei; Lu, Fan-zhen; Shen, Xiao-Yong; Wu, Yun; Zhao, Li-ting

2014-01-01

Highlights: • SAMHD1 expression level is down regulated in lung adenocarcinoma. • The promoter of SAMHD1 is methylated in lung adenocarcinoma. • Over expression of SAMHD1 inhibits the proliferation of lung cancer cells. - Abstract: The function of dNTP hydrolase SAMHD1 as a viral restriction factor to inhibit the replication of several viruses in human immune cells was well established. However, its regulation and function in lung cancer have been elusive. Here, we report that SAMHD1 is down regulated both on protein and mRNA levels in lung adenocarcinoma compared to adjacent normal tissue. We also found that SAMHD1 promoter is highly methylated in lung adenocarcinoma, which may inhibit its gene expression. Furthermore, over expression of the SAMHD1 reduces dNTP level and inhibits the proliferation of lung tumor cells. These results reveal the regulation and function of SAMHD1 in lung cancer, which is important for the proliferation of lung tumor cells

Neuroprotection by biodegradable PAMAM ester (e-PAM-R)-mediated HMGB1 siRNA delivery in primary cortical cultures and in the postischemic brain.

Science.gov (United States)

Kim, Il-Doo; Lim, Chae-Moon; Kim, Jung-Bin; Nam, Hye Yeong; Nam, Kihoon; Kim, Seung-Woo; Park, Jong-Sang; Lee, Ja-Kyeong

2010-03-19

Although RNA interference (RNAi)-mediated gene silencing provides a powerful strategy for modulating specific gene functions, difficulties associated with siRNA delivery have impeded the development of efficient therapeutic applications. In particular, the efficacy of siRNA delivery into neurons has been limited by extremely low transfection efficiencies. e-PAM-R is a biodegradable arginine ester of PAMAM dendrimer, which is readily degradable under physiological conditions (pH 7.4, 37 degrees C). In the present study, we investigated the efficiency of siRNA delivery by e-PAM-R in primary cortical cultures and in rat brain. e-PAM-R/siRNA complexes showed high transfection efficiencies and low cytotoxicities in primary cortical cultures. Localization of fluorescence-tagged siRNA revealed that siRNA was delivered not only into the nucleus and cytoplasm, but also along the processes of the neuron. e-PAM-R/siRNA complex-mediated target gene reduction was observed in over 40% of cells and it was persistent for over 48 h. The potential use of e-PAM-R was demonstrated by gene knockdown after transfecting High mobility group box-1 (HMGB1, a novel cytokine-like molecule) siRNA into H(2)O(2)- or NMDA-treated primary cortical cultures. In these cells, HMGB1 siRNA delivery successfully reduced both basal and H(2)O(2)- or NMDA-induced HMGB1 levels, and as a result of that, neuronal cell death was significantly suppressed in both cases. Furthermore, we showed that e-PAM-R successfully delivered HMGB1 siRNA into the rat brain, wherein HMGB1 expression was depleted in over 40% of neurons and astrocytes of the normal brain. Moreover, e-PAM-R-mediated HMGB1 siRNA delivery notably reduced infarct volume in the postischemic rat brain, which is generated by occluding the middle cerebral artery for 60 min. These results indicate that e-PAM-R, a novel biodegradable nonviral gene carrier, offers an efficient means of transfecting siRNA into primary neuronal cells and in the brain and of

BMP6 down-regulates GDNF expression through SMAD1/5 and ERK1/2 signaling pathways in human granulosa-lutein cells.

Science.gov (United States)

Zhang, Xin-Yue; Chang, Hsun-Ming; Taylor, Elizabeth L; Leung, Peter C K; Liu, Rui-Zhi

2018-05-09

Bone morphogenetic protein 6 (BMP6) is a critical regulator of follicular development that is expressed in mammalian oocytes and granulosa cells. Glial cell line-derived neurotrophic factor (GDNF) is an intraovarian neurotrophic factor that plays an essential role in regulating mammalian oocyte maturation. The aim of this study was to investigate the effect of BMP6 on the regulation of GDNF expression and the potential underlying mechanisms. We used an established immortalized human granulosa cell line (SVOG cells) and primary human granulosa-lutein cells as in vitro cell models. Our results showed that BMP6 significantly down-regulated the expression of GDNF in both SVOG and primary human granulosa-lutein cells. Using dual inhibition approaches (kinase receptor inhibitor and small interfering RNA knockdown), our results showed that both ALK2 and ALK3 are involved in BMP6-induced down-regulation of GDNF. In addition, BMP6 induced the phosphorylation of SMAD1/5/8 and ERK1/2 but not AKT or p38. Among three downstream mediators, both SMAD1 and SMAD5 are involved in BMP6-induced down-regulation of GDNF. Moreover, concomitant knockdown of endogenous SMAD4 and inhibition of ERK1/2 activity completely reversed BMP6-induced down-regulation of GDNF, indicating that both SMAD and ERK1/2 signaling pathways are required for the regulatory effect of BMP6 on GDNF expression. Our findings suggest an additional role for an intrafollicular growth factor in regulating follicular function through their paracrine interactions in human granulosa cells.

Women's experience of rage: a critical feminist analysis.

Science.gov (United States)

Flemke, Kimberly; Allen, Katherine R

2008-01-01

We conducted in-depth interviews with 37 incarcerated women on their experience of rage towards their intimate partner. Participants used specific criteria to distinguish their experience of rage from anger. Rage is described as an overwhelming experience with particular physiological and cognitive changes that takes control of a woman's emotions and actions. In contrast, anger is described as a controllable emotion with a specific termination point. Motivations for acting violently in rage with an intimate partner are described and discussed. Findings suggest a primary trigger for experiencing rage is feeling threatened and feeling emotionally overwhelmed.

Punicalagin, a PTP1B inhibitor, induces M2c phenotype polarization via up-regulation of HO-1 in murine macrophages.

Science.gov (United States)

Xu, Xiaolong; Guo, Yuhong; Zhao, Jingxia; He, Shasha; Wang, Yan; Lin, Yan; Wang, Ning; Liu, Qingquan

2017-09-01

Current data have shown that punicalagin (PUN), an ellagitannin isolated from pomegranate, possesses anti-inflammatory and anti-oxidant properties; however, its direct targets have not yet been reported. This is the first report that PTP1B serves as a direct target of PUN, with IC 50 value of 1.04μM. Results from NPOI further showed that the K on and K off of PUN-PTP1B complex were 3.38e2M -1 s -1 and 4.13e-3s -1 , respectively. The active site Arg24 of PTP1B was identified as a key binding site of PUN by computation simulation and point mutation. Moreover, inhibition of PTP1B by PUN promoted an M2c-like macrophage polarization and enhanced anti-inflammatory cytokines expression, including IL-10 and M-CSF. Based on gene expression profile, we elucidated that PUN treatment significantly up-regulated 275 genes and down-regulated 1059 genes. M1-like macrophage marker genes, such as Tlr4, Irf1/2, Hmgb1, and Stat1 were down-regulated, while M2 marker genes, including Tmem171, Gpr35, Csf1, Il1rn, Cebpb, Fos, Vegfα, Slc11a1, and Bhlhe40 were up-regulated in PUN-treated macrophages. Hmox-1, a gene encoding HO-1 protein, was preferentially expressed with 16-fold change. Inhibition of HO-1 obviously restored PUN-induced M2 polarization and IL-10 secretion. In addition, phosphorylation of both Akt and STAT3 contributed to PUN-induced HO-1 expression. This study provided new insights into the mechanisms of PUN-mediated anti-inflammatory and anti-oxidant activities and provided new therapeutic strategies for inflammatory diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Microglial-derived miRNA let-7 and HMGB1 contribute to ethanol-induced neurotoxicity via TLR7.

Science.gov (United States)

Coleman, Leon G; Zou, Jian; Crews, Fulton T

2017-01-25

Toll-like receptor (TLR) signaling is emerging as an important component of neurodegeneration. TLR7 senses viral RNA and certain endogenous miRNAs to initiate innate immune responses leading to neurodegeneration. Alcoholism is associated with hippocampal degeneration, with preclinical studies linking ethanol-induced neurodegeneration with central innate immune induction and TLR activation. The endogenous miRNA let-7b binds TLR7 to cause neurodegeneration. TLR7 and other immune markers were assessed in postmortem human hippocampal tissue that was obtained from the New South Wales Tissue Bank. Rat hippocampal-entorhinal cortex (HEC) slice culture was used to assess specific effects of ethanol on TLR7, let-7b, and microvesicles. We report here that hippocampal tissue from postmortem human alcoholic brains shows increased expression of TLR7 and increased microglial activation. Using HEC slice culture, we found that ethanol induces TLR7 and let-7b expression. Ethanol caused TLR7-associated neuroimmune gene induction and initiated the release let-7b in microvesicles (MVs), enhancing TLR7-mediated neurotoxicity. Further, ethanol increased let-7b binding to the danger signaling molecule high mobility group box-1 (HMGB1) in MVs, while reducing let-7 binding to classical chaperone protein argonaute (Ago2). Flow cytometric analysis of MVs from HEC media and analysis of MVs from brain cell culture lines found that microglia were the primary source of let-7b and HMGB1-containing MVs. Our results identify that ethanol induces neuroimmune pathology involving the release of let-7b/HMGB1 complexes in microglia-derived microvesicles. This contributes to hippocampal neurodegeneration and may play a role in the pathology of alcoholism.

The AGE-RAGE Axis: Implications for Age-Associated Arterial Diseases

Directory of Open Access Journals (Sweden)

Laura M. Senatus

2017-12-01

Full Text Available The process of advanced glycation leads to the generation and accumulation of an heterogeneous class of molecules called advanced glycation endproducts, or AGEs. AGEs are produced to accelerated degrees in disorders such as diabetes, renal failure, inflammation, neurodegeneration, and in aging. Further, AGEs are present in foods and in tobacco products. Hence, through both endogenous production and exogenous consumption, AGEs perturb vascular homeostasis by a number of means; in the first case, AGEs can cause cross-linking of long-lived molecules in the basement membranes such as collagens, thereby leading to “vascular stiffening” and processes that lead to hyperpermeability and loss of structural integrity. Second, AGEs interaction with their major cell surface signal transduction receptor for AGE or RAGE sets off a cascade of events leading to modulation of gene expression and loss of vascular and tissue homeostasis, processes that contribute to cardiovascular disease. In addition, it has been shown that an enzyme, which plays key roles in the detoxification of pre-AGE species, glyoxalase 1 (GLO1, is reduced in aged and diabetic tissues. In the diabetic kidney devoid of Ager (gene encoding RAGE, higher levels of Glo1 mRNA and GLO1 protein and activity were observed, suggesting that in conditions of high AGE accumulation, natural defenses may be mitigated, at least in part through RAGE. AGEs are a marker of arterial aging and may be detected by both biochemical means, as well as measurement of “skin autofluorescence.” In this review, we will detail the pathobiology of the AGE-RAGE axis and the consequences of its activation in the vasculature and conclude with potential avenues for therapeutic interruption of the AGE-RAGE ligand-RAGE pathways as means to forestall the deleterious consequences of AGE accumulation and signaling via RAGE.

The herpes simplex virus receptor nectin-1 is down-regulated after trans-interaction with glycoprotein D

International Nuclear Information System (INIS)

Stiles, Katie M.; Milne, Richard S.B.; Cohen, Gary H.; Eisenberg, Roselyn J.; Krummenacher, Claude

2008-01-01

During herpes simplex virus (HSV) entry, membrane fusion occurs either on the cell surface or after virus endocytosis. In both cases, binding of glycoprotein D (gD) to a receptor such as nectin-1 or HVEM is required. In this study, we co-cultured cells expressing gD with nectin-1 expressing cells to investigate the effects of gD on nectin-1 at cell contacts. After overnight co-cultures with gD expressing cells, there was a down-regulation of nectin-1 in B78H1-C10, SY5Y, A431 and HeLa cells, which HSV enters by endocytosis. In contrast, on Vero cells, which HSV enters at the plasma membrane, nectin-1 was not down-regulated. Further analysis of B78H1-derived cells showed that nectin-1 down-regulation corresponds to the ability of gD to bind nectin-1 and is achieved by internalization and low-pH-dependent degradation of nectin-1. Moreover, gD is necessary for virion internalization in B78H1 cells expressing nectin-1. These data suggest that the determinants of gD-mediated internalization of nectin-1 may direct HSV to an endocytic pathway during entry

MR imaging in epilepsy with use of 3D MP-RAGE

International Nuclear Information System (INIS)

Tanaka, Akio; Ohno, Sigeru; Sei, Tetsuro; Kanazawa, Susumu; Yasui, Koutaro; Kuroda, Masahiro; Hiraki, Yoshio; Oka, Eiji

1996-01-01

The patients were 40 males and 33 females; their ages ranged from 1 month to 39 years (mean: 15.7 years). The patients underwent MR imaging, including spin-echo T 1 -weighted, turbo spin-echo proton density/T 2 -weighted, and 3D magnetization-prepared rapid gradient-echo (3D MP-RAGE) images. These examinations disclosed 39 focal abnormalities. On visual evaluation, the boundary of abnormal gray matter in the neuronal migration disorder (NMD) cases was most clealy shown on 3D MP-RAGE images as compared to the other images. This is considered to be due to the higher spatial resolution and the better contrast of the 3D MP-RAGE images than those of the other techniques. The relative contrast difference between abnormal gray matter and the adjacent white matter was also assessed. The results revealed that the contrast differences on the 3D MP-RAGE images were larger than those on the other images; this was statistically significant. Although the sensitivity of 3D MP-RAGE for NMD was not specifically evaluated in this study, the possibility of this disorder, in cases suspected on other images, could be ruled out. Thus, it appears that the specificity with respect to NMD was at least increased with us of 3D MP-RAGE. 3D MP-RAGE also enabled us to build three-dimensional surface models that were helpful in understanding the three-dimensional anatomy. Furthermore. 3D MP-RAGE was considered to be the best technique for evaluating hippocampus atrophy in patients with MTS. On the other hand, the sensitivity in the signal change of the hippocampus was higher on T 2 -weighted images. In addition, demonstration of cortical tubers of tuberous sclerosis in neurocutaneous syndrome was superior on T 2 -weighted images than on 3D MP-RAGE images. (K.H.)

Sensitization of multidrug-resistant human cancer cells to Hsp90 inhibitors by down-regulation of SIRT1

Science.gov (United States)

Kim, Hak-Bong; Lee, Su-Hoon; Um, Jee-Hyun; Oh, Won Keun; Kim, Dong-Wan; Kang, Chi-Dug; Kim, Sun-Hee

2015-01-01

The effectiveness of Hsp90 inhibitors as anticancer agents was limited in multidrug-resistant (MDR) human cancer cells due to induction of heat shock proteins (Hsps) such as Hsp70/Hsp27 and P-glycoprotein (P-gp)-mediated efflux. In the present study, we showed that resistance to Hsp90 inhibitors of MDR human cancer cells could be overcome with SIRT1 inhibition. SIRT1 knock-down or SIRT1 inhibitors (amurensin G and EX527) effectively suppressed the resistance to Hsp90 inhibitors (17-AAG and AUY922) in several MDR variants of human lymphoblastic leukemia and human breast cancer cell lines. SIRT1 inhibition down-regulated the expression of heat shock factor 1 (HSF1) and subsequently Hsps and facilitated Hsp90 multichaperone complex disruption via hyperacetylation of Hsp90/Hsp70. These findings were followed by acceleration of ubiquitin ligase CHIP-mediated mutant p53 (mut p53) degradation and subsequent down-regulation of P-gp in 17-AAG-treated MDR cancer cells expressing P-gp and mut p53 after inhibition of SIRT1. Therefore, combined treatment with Hsp90 inhibitor and SIRT1 inhibitor could be a more effective therapeutic approach for Hsp90 inhibitor-resistant MDR cells via down-regulation of HSF1/Hsps, mut p53 and P-gp. PMID:26416354

MicroRNA-Mediated Down-Regulation of Apoptosis Signal-Regulating Kinase 1 (ASK1) Attenuates the Apoptosis of Human Mesenchymal Stem Cells (MSCs) Transplanted into Infarcted Heart.

Science.gov (United States)

Lee, Chang Youn; Shin, Sunhye; Lee, Jiyun; Seo, Hyang-Hee; Lim, Kyu Hee; Kim, Hyemin; Choi, Jung-Won; Kim, Sang Woo; Lee, Seahyung; Lim, Soyeon; Hwang, Ki-Chul

2016-10-20

Stem cell therapy using adult stem cells, such as mesenchymal stem cells (MSCs) has produced some promising results in treating the damaged heart. However, the low survival rate of MSCs after transplantation is still one of the crucial factors that limit the therapeutic effect of stem cells. In the damaged heart, oxidative stress due to reactive oxygen species (ROS) production can cause the death of transplanted MSCs. Apoptosis signal-regulating kinase 1 (ASK1) has been implicated in the development of oxidative stress-related pathologic conditions. Thus, we hypothesized that down-regulation of ASK1 in human MSCs (hMSCs) might attenuate the post-transplantation death of MSCs. To test this hypothesis, we screened microRNAs (miRNAs) based on a miRNA-target prediction database and empirical data and investigated the anti-apoptotic effect of selected miRNAs on human adipose-derived stem cells (hASCs) and on rat myocardial infarction (MI) models. Our data indicated that miRNA-301a most significantly suppressed ASK1 expression in hASCs. Apoptosis-related genes were significantly down-regulated in miRNA-301a-enriched hASCs exposed to hypoxic conditions. Taken together, these data show that miRNA-mediated down-regulation of ASK1 protects MSCs during post-transplantation, leading to an increase in the efficacy of MSC-based cell therapy.

MicroRNA-Mediated Down-Regulation of Apoptosis Signal-Regulating Kinase 1 (ASK1 Attenuates the Apoptosis of Human Mesenchymal Stem Cells (MSCs Transplanted into Infarcted Heart

Directory of Open Access Journals (Sweden)

Chang Youn Lee

2016-10-01

Full Text Available Stem cell therapy using adult stem cells, such as mesenchymal stem cells (MSCs has produced some promising results in treating the damaged heart. However, the low survival rate of MSCs after transplantation is still one of the crucial factors that limit the therapeutic effect of stem cells. In the damaged heart, oxidative stress due to reactive oxygen species (ROS production can cause the death of transplanted MSCs. Apoptosis signal-regulating kinase 1 (ASK1 has been implicated in the development of oxidative stress-related pathologic conditions. Thus, we hypothesized that down-regulation of ASK1 in human MSCs (hMSCs might attenuate the post-transplantation death of MSCs. To test this hypothesis, we screened microRNAs (miRNAs based on a miRNA-target prediction database and empirical data and investigated the anti-apoptotic effect of selected miRNAs on human adipose-derived stem cells (hASCs and on rat myocardial infarction (MI models. Our data indicated that miRNA-301a most significantly suppressed ASK1 expression in hASCs. Apoptosis-related genes were significantly down-regulated in miRNA-301a-enriched hASCs exposed to hypoxic conditions. Taken together, these data show that miRNA-mediated down-regulation of ASK1 protects MSCs during post-transplantation, leading to an increase in the efficacy of MSC-based cell therapy.

The association between the RAGE G82S polymorphism, sRAGE and chronic periodontitis in Taiwanese individuals with and without diabetes.

Science.gov (United States)

Wu, T-L; Tsai, C-C; Wang, Y-Y; Ho, K-Y; Wu, Y-M; Hung, H-C; Lin, Y-C

2015-12-01

The present study investigated the association between the RAGE G82S polymorphism, the plasma levels of sRAGE and chronic periodontitis in subjects with and without diabetes mellitus (DM). A total of 230 patients with DM and 264 non-DM participants were recruited for this study. Genotyping of the RAGE G82S polymorphism was accomplished using polymerase chain reaction-restriction fragment length polymorphism, and associations were analyzed with the chi-squared test and logistic regression analysis. In the non-DM group, the chi-squared test showed that the frequency distributions of the G82S polymorphism were significantly different between chronic periodontitis and non-chronic periodontitis subjects (χ(2) = 8.39, p = 0.02). A multivariate logistic regression model showed that the (G82S + S82S) genotypes were associated with a significantly increased risk of chronic periodontitis development compared to the G82G genotype (adjusted odds ratio = 2.06, 95% confidence interval: 1.08-4.07). In the DM group, there was no association between the G82S polymorphism and chronic periodontitis development when a multivariate logistic regression was performed. Plasma levels of sRAGE were significantly higher in subjects with the G82G genotype compared to those with the (G82S + S82S) genotypes in both the non-DM (856.6 ± 332.0 vs. 720.4 ± 311.4 pg/mL, p = 0.003) and DM groups (915.3 ± 497.1 vs. 603.5 ± 298.3 pg/mL, p chronic periodontitis and non-chronic periodontitis subjects in both the DM and non-DM groups. Moreover, when the subjects were further sub-divided by the G82S polymorphism, the difference in plasma levels of sRAGE between chronic periodontitis and non-chronic periodontitis subjects in the DM and non-DM groups remained statistically insignificant. The present study revealed that the RAGE G82S polymorphism was associated with chronic periodontitis in the non-DM group but not in the DM group. Our results also showed that the plasma levels of sRAGE were

Dynamic changes in sRAGE levels and relationship with cardiac function in STEMI patients

DEFF Research Database (Denmark)

Jensen, Louise J N; Lindberg, Søren; Hoffmann, Søren

2015-01-01

the dynamic changes in sRAGE levels during AMI and relationship with cardiac dysfunction. DESIGN AND METHODS: We prospectively included 80 patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI). sRAGE concentrations were measured before p...... in the early phase of AMI; sRAGE levels significantly increased after pPCI compared with sRAGE before pPCI (median ratio: 1.25, 95% CI: 1.15-1.35, P...phase rather than in the days after AMI and pPCI. The increase...

Decreased levels of sRAGE in follicular fluid from patients with PCOS.

Science.gov (United States)

Wang, BiJun; Li, Jing; Yang, QingLing; Zhang, FuLi; Hao, MengMeng; Guo, YiHong

2017-03-01

This study aimed to explore the association between soluble receptor for advanced glycation end products (sRAGE) levels in follicular fluid and the number of oocytes retrieved and to evaluate the effect of sRAGE on vascular endothelial growth factor (VEGF) in granulosa cells in patients with polycystic ovarian syndrome (PCOS). Two sets of experiments were performed in this study. In part one, sRAGE and VEGF protein levels in follicular fluid samples from 39 patients with PCOS and 35 non-PCOS patients were measured by ELISA. In part two, ovarian granulosa cells were isolated from an additional 10 patients with PCOS and cultured. VEGF and SP1 mRNA and protein levels, as well as pAKT levels, were detected by real-time PCR and Western blotting after cultured cells were treated with different concentrations of sRAGE. Compared with the non-PCOS patients, patients with PCOS had lower sRAGE levels in follicular fluid. Multi-adjusted regression analysis showed that high sRAGE levels in follicular fluid predicted a lower Gn dose, more oocytes retrieved, and a better IVF outcome in the non-PCOS group. Logistic regression analysis showed that higher sRAGE levels predicted favorably IVF outcomes in the non-PCOS group. Multi-adjusted regression analysis also showed that high sRAGE levels in follicular fluid predicted a lower Gn dose in the PCOS group. Treating granulosa cells isolated from patients with PCOS with recombinant sRAGE decreased VEGF and SP1 mRNA and protein expression and pAKT levels in a dose-dependent manner. © 2017 Society for Reproduction and Fertility.

The receptor RAGE: Bridging inflammation and cancer

Directory of Open Access Journals (Sweden)

Hess Jochen

2009-05-01

Full Text Available Abstract The receptor for advanced glycation end products (RAGE is a single transmembrane receptor of the immunoglobulin superfamily that is mainly expressed on immune cells, neurons, activated endothelial and vascular smooth muscle cells, bone forming cells, and a variety of cancer cells. RAGE is a multifunctional receptor that binds a broad repertoire of ligands and mediates responses to cell damage and stress conditions. It activates programs responsible for acute and chronic inflammation, and is implicated in a number of pathological diseases, including diabetic complications, stroke, atheriosclerosis, arthritis, and neurodegenerative disorders. The availability of Rage knockout mice has not only advanced our knowledge on signalling pathways within these pathophysiological conditions, but also on the functional importance of the receptor in processes of cancer. Here, we will summarize molecular mechanisms through which RAGE signalling contributes to the establishment of a pro-tumourigenic microenvironment. Moreover, we will review recent findings that provide genetic evidence for an important role of RAGE in bridging inflammation and cancer.

In vitro anticancer effects of a RAGE inhibitor discovered using a structure-based drug design system

Science.gov (United States)

El-Far, Ali Hafez Ali Mohammed; Munesue, Seiichi; Harashima, Ai; Sato, Akira; Shindo, Mika; Nakajima, Shingo; Inada, Mana; Tanaka, Mariko; Takeuchi, Akihiko; Tsuchiya, Hiroyuki; Yamamoto, Hiroshi; Shaheen, Hazem M.E.; El-Sayed, Yasser S.; Kawano, Shuhei; Tanuma, Sei-Ichi; Yamamoto, Yasuhiko

2018-01-01

Receptor for advanced glycation end-products (RAGE) is a pattern recognition receptor implicated in the pathogenesis of certain types of cancer. In the present study, papaverine was identified as a RAGE inhibitor using the conversion to small molecules through optimized-peptide strategy drug design system. Papaverine significantly inhibited RAGE-dependent nuclear factor κ-B activation driven by high mobility group box-1, a RAGE ligand. Using RAGE- or dominant-negative RAGE-expressing HT1080 human fibrosarcoma cells, the present study revealed that papaverine suppressed RAGE-dependent cell proliferation and migration dose-dependently. Furthermore, papaverine significantly inhibited cell invasion. The results of the present study suggested that papaverine could inhibit RAGE, and provided novel insights into the field of RAGE biology, particularly anticancer therapies. PMID:29541234

Znhit1 causes cell cycle arrest and down-regulates CDK6 expression

International Nuclear Information System (INIS)

Yang, Zhengmin; Cao, Yonghao; Zhu, Xiaoyan; Huang, Ying; Ding, Yuqiang; Liu, Xiaolong

2009-01-01

Cyclin-dependent kinase 6 (CDK6) is the key element of the D-type cyclin holoenzymes which has been found to function in the regulation of G1-phase of the cell cycle and is presumed to play important roles in T cell function. In this study, Znhit1, a member of a new zinc finger protein family defined by a conserved Zf-HIT domain, induced arrest in the G1-phase of the cell cycle in NIH/3T3 cells. Of the G1 cell cycle factors examined, the expression of CDK6 was found to be strongly down-regulated by Znhit1 via transcriptional repression. This effect may have correlations with the decreased acetylation level of histone H4 in the CDK6 promoter region. In addition, considering that CDK6 expression predominates in T cells, the negative regulatory role of Znhit1 in TCR-induced T cell proliferation was validated using transgenic mice. These findings identified Znhit1 as a CDK6 regulator that plays an important role in cell proliferation.

Down-regulation of Wild-type p53-induced Phosphatase 1 (Wip1) Plays a Critical Role in Regulating Several p53-dependent Functions in Premature Senescent Tumor Cells*

Science.gov (United States)

Crescenzi, Elvira; Raia, Zelinda; Pacifico, Francesco; Mellone, Stefano; Moscato, Fortunato; Palumbo, Giuseppe; Leonardi, Antonio

2013-01-01

Premature or drug-induced senescence is a major cellular response to chemotherapy in solid tumors. The senescent phenotype develops slowly and is associated with chronic DNA damage response. We found that expression of wild-type p53-induced phosphatase 1 (Wip1) is markedly down-regulated during persistent DNA damage and after drug release during the acquisition of the senescent phenotype in carcinoma cells. We demonstrate that down-regulation of Wip1 is required for maintenance of permanent G2 arrest. In fact, we show that forced expression of Wip1 in premature senescent tumor cells induces inappropriate re-initiation of mitosis, uncontrolled polyploid progression, and cell death by mitotic failure. Most of the effects of Wip1 may be attributed to its ability to dephosphorylate p53 at Ser15 and to inhibit DNA damage response. However, we also uncover a regulatory pathway whereby suppression of p53 Ser15 phosphorylation is associated with enhanced phosphorylation at Ser46, increased p53 protein levels, and induction of Noxa expression. On the whole, our data indicate that down-regulation of Wip1 expression during premature senescence plays a pivotal role in regulating several p53-dependent aspects of the senescent phenotype. PMID:23612976

RAGE: a new frontier in chronic airways disease

Science.gov (United States)

Sukkar, Maria B; Ullah, Md Ashik; Gan, Wan Jun; Wark, Peter AB; Chung, Kian Fan; Hughes, J Margaret; Armour, Carol L; Phipps, Simon

2012-01-01

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous inflammatory disorders of the respiratory tract characterized by airflow obstruction. It is now clear that the environmental factors that drive airway pathology in asthma and COPD, including allergens, viruses, ozone and cigarette smoke, activate innate immune receptors known as pattern-recognition receptors, either directly or indirectly by causing the release of endogenous ligands. Thus, there is now intense research activity focused around understanding the mechanisms by which pattern-recognition receptors sustain the airway inflammatory response, and how these mechanisms might be targeted therapeutically. One pattern-recognition receptor that has recently come to attention in chronic airways disease is the receptor for advanced glycation end products (RAGE). RAGE is a member of the immunoglobulin superfamily of cell surface receptors that recognizes pathogen- and host-derived endogenous ligands to initiate the immune response to tissue injury, infection and inflammation. Although the role of RAGE in lung physiology and pathophysiology is not well understood, recent genome-wide association studies have linked RAGE gene polymorphisms with airflow obstruction. In addition, accumulating data from animal and clinical investigations reveal increased expression of RAGE and its ligands, together with reduced expression of soluble RAGE, an endogenous inhibitor of RAGE signalling, in chronic airways disease. In this review, we discuss recent studies of the ligand–RAGE axis in asthma and COPD, highlight important areas for future research and discuss how this axis might potentially be harnessed for therapeutic benefit in these conditions. PMID:22506507

Interactions of Histone Acetyltransferase p300 with the Nuclear Proteins Histone and HMGB1, As Revealed by Single Molecule Atomic Force Spectroscopy.

Science.gov (United States)

Banerjee, S; Rakshit, T; Sett, S; Mukhopadhyay, R

2015-10-22

One of the important properties of the transcriptional coactivator p300 is histone acetyltransferase (HAT) activity that enables p300 to influence chromatin action via histone modulation. p300 can exert its HAT action upon the other nuclear proteins too--one notable example being the transcription-factor-like protein HMGB1, which functions also as a cytokine, and whose accumulation in the cytoplasm, as a response to tissue damage, is triggered by its acetylation. Hitherto, no information on the structure and stability of the complexes between full-length p300 (p300FL) (300 kDa) and the histone/HMGB1 proteins are available, probably due to the presence of unstructured regions within p300FL that makes it difficult to be crystallized. Herein, we have adopted the high-resolution atomic force microscopy (AFM) approach, which allows molecularly resolved three-dimensional contour mapping of a protein molecule of any size and structure. From the off-rate and activation barrier values, obtained using single molecule dynamic force spectroscopy, the biochemical proposition of preferential binding of p300FL to histone H3, compared to the octameric histone, can be validated. Importantly, from the energy landscape of the dissociation events, a model for the p300-histone and the p300-HMGB1 dynamic complexes that HAT forms, can be proposed. The lower unbinding forces of the complexes observed in acetylating conditions, compared to those observed in non-acetylating conditions, indicate that upon acetylation, p300 tends to weakly associate, probably as an outcome of charge alterations on the histone/HMGB1 surface and/or acetylation-induced conformational changes. To our knowledge, for the first time, a single molecule level treatment of the interactions of HAT, where the full-length protein is considered, is being reported.

Mechanisms Down-Regulating Sprouty1, a Growth Inhibitor in Prostate Cancer

Science.gov (United States)

2008-10-01

fibroblast growth factor signaling is down-regulated in prostate cancer. Kwabi-Addo B (2004) Orlando, FL (Oral; mini symposium). • AACR/NCI/EORTC...contains a classic signal peptide PP FRS2 Sos Grb2 Cbl Ras FGFR1-DN MEK ERK STAT3 STAT3 Sprouty PLC - Extracellular stimulus Nucleus P Raf PI3K Receptor... thesis system for reverse transcription-PCR and according to the manufactur- er’s protocol. Real-time PCR was carried out in a Bio-Rad iCycler real

Essential roles of high-mobility group box 1 in the development of murine colitis and colitis-associated cancer

International Nuclear Information System (INIS)

Maeda, Shin; Hikiba, Yohko; Shibata, Wataru; Ohmae, Tomoya; Yanai, Ayako; Ogura, Keiji; Yamada, Shingo; Omata, Masao

2007-01-01

High-mobility group box 1 (HMGB1) is a nuclear factor released extracellularly as a proinflammatory cytokine. We measured the HMGB1 concentration in the sera of mice with chemically induced colitis (DSS; dextran sulfate sodium salt) and found a marked increase. Inhibition of HMGB1 by neutralizing anti-HMGB1 antibody resulted in reduced inflammation in DSS-treated colons. In macrophages, HMGB1 induces several proinflammatory cytokines, such as IL-6, which are regulated by NF-κB activation. Two putative sources of HMGB1 were explored: in one, bacterial factors induce HMGB1 secretion from macrophages and in the other, necrotic epithelial cells directly release HMGB1. LPS induced a small amount of HMGB1 in macrophages, but macrophages incubated with supernatant prepared from necrotic cells and containing large amounts of HMGB1 activated NF-κB and induced IL-6. Using the colitis-associated cancer model, we demonstrated that neutralizing anti-HMGB1 antibody decreases tumor incidence and size. These observations suggest that HMGB1 is a potentially useful target for IBD treatment and the prevention of colitis-associated cancer

RAGE: a new frontier in chronic airways disease.

Science.gov (United States)

Sukkar, Maria B; Ullah, Md Ashik; Gan, Wan Jun; Wark, Peter A B; Chung, Kian Fan; Hughes, J Margaret; Armour, Carol L; Phipps, Simon

2012-11-01

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous inflammatory disorders of the respiratory tract characterized by airflow obstruction. It is now clear that the environmental factors that drive airway pathology in asthma and COPD, including allergens, viruses, ozone and cigarette smoke, activate innate immune receptors known as pattern-recognition receptors, either directly or indirectly by causing the release of endogenous ligands. Thus, there is now intense research activity focused around understanding the mechanisms by which pattern-recognition receptors sustain the airway inflammatory response, and how these mechanisms might be targeted therapeutically. One pattern-recognition receptor that has recently come to attention in chronic airways disease is the receptor for advanced glycation end products (RAGE). RAGE is a member of the immunoglobulin superfamily of cell surface receptors that recognizes pathogen- and host-derived endogenous ligands to initiate the immune response to tissue injury, infection and inflammation. Although the role of RAGE in lung physiology and pathophysiology is not well understood, recent genome-wide association studies have linked RAGE gene polymorphisms with airflow obstruction. In addition, accumulating data from animal and clinical investigations reveal increased expression of RAGE and its ligands, together with reduced expression of soluble RAGE, an endogenous inhibitor of RAGE signalling, in chronic airways disease. In this review, we discuss recent studies of the ligand-RAGE axis in asthma and COPD, highlight important areas for future research and discuss how this axis might potentially be harnessed for therapeutic benefit in these conditions. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Biphasic Modulation of NOS Expression, Protein and Nitrite Products by Hydroxocobalamin Underlies Its Protective Effect in Endotoxemic Shock: Downstream Regulation of COX-2, IL-1β, TNF-α, IL-6, and HMGB1 Expression

Science.gov (United States)

Sampaio, André L. F.; Dalli, Jesmond; Brancaleone, Vincenzo; D'Acquisto, Fulvio; Perretti, Mauro; Wheatley, Carmen

2013-01-01

Background. NOS/•NO inhibitors are potential therapeutics for sepsis, yet they increase clinical mortality. However, there has been no in vivo investigation of the (in vitro) •NO scavenger, cobalamin's (Cbl) endogenous effects on NOS/•NO/inflammatory mediators during the immune response to sepsis. Methods. We used quantitative polymerase chain reaction (qPCR), ELISA, Western blot, and NOS Griess assays, in a C57BL/6 mouse, acute endotoxaemia model. Results. During the immune response, pro-inflammatory phase, parenteral hydroxocobalamin (HOCbl) treatment partially inhibits hepatic, but not lung, iNOS mRNA and promotes lung eNOS mRNA, but attenuates the LPS hepatic rise in eNOS mRNA, whilst paradoxically promoting high iNOS/eNOS protein translation, but relatively moderate •NO production. HOCbl/NOS/•NO regulation is reciprocally associated with lower 4 h expression of TNF-α, IL-1β, COX-2, and lower circulating TNF-α, but not IL-6. In resolution, 24 h after LPS, HOCbl completely abrogates a major late mediator of sepsis mortality, high mobility group box 1 (HMGB1) mRNA, inhibits iNOS mRNA, and attenuates LPS-induced hepatic inhibition of eNOS mRNA, whilst showing increased, but still moderate, NOS activity, relative to LPS only. experiments (LPS+D-Galactosamine) HOCbl afforded significant, dose-dependent protection in mice Conclusions. HOCbl produces a complex, time- and organ-dependent, selective regulation of NOS/•NO during endotoxaemia, corollary regulation of downstream inflammatory mediators, and increased survival. This merits clinical evaluation. PMID:23781123

Oligomerization interface of RAGE receptor revealed by MS-monitored hydrogen deuterium exchange.

Directory of Open Access Journals (Sweden)

Ewa Sitkiewicz

Full Text Available Activation of the receptor for advanced glycation end products (RAGE leads to a chronic proinflammatory signal, affecting patients with a variety of diseases. Potentially beneficial modification of RAGE activity requires understanding the signal transduction mechanism at the molecular level. The ligand binding domain is structurally uncoupled from the cytoplasmic domain, suggesting receptor oligomerization is a requirement for receptor activation. In this study, we used hydrogen-deuterium exchange and mass spectrometry to map structural differences between the monomeric and oligomeric forms of RAGE. Our results indicated the presence of a region shielded from exchange in the oligomeric form of RAGE and led to the identification of a new oligomerization interface localized at the linker region between domains C1 and C2. Based on this finding, a model of a RAGE dimer and higher oligomeric state was constructed.

miR-133b down-regulates ABCC1 and enhances the sensitivity of CRC to anti-tumor drugs.

Science.gov (United States)

Chen, Miao; Li, Daojiang; Gong, Ni; Wu, Hao; Su, Chen; Xie, Canbin; Xiang, Hong; Lin, Changwei; Li, Xiaorong

2017-08-08

Multidrug resistance (MDR) is the main cause of failed chemotherapy treatments. Therefore, preventing MDR is pivotal in treating colorectal cancer (CRC). In a previous study miR-133b was shown to be a tumor suppressor. Additionally, in CRC cells transfected with miR-133b, ATP-binding cassette (ABC) subfamily C member 1(ABCC1) was shown to be significantly down regulated. Whether miR-133b also enhances the chemosensitivity of drugs used to treat CRC by targeting ABCC1 is still unclear. Here, we utilized flow cytometry and high-performance liquid chromatography (HPLC) analysis to identify the ability of miR-133b to reserve MDR in CRC. We then used a dual-luciferase reporter assay to validate that miR-133b targets ABCC1. Further in vivo experiments were designed to validate the method in which miR-133b reversed MDR in CRC cells. The results demonstrated that the level of miR-133b was down-regulated and the expression of ABCC1 was up-regulated in drug-resistant CRC cells compared to non-drug-resistant CRC cells. The restoration of miR-133b expression in CRC drug-resistant cells in vitro resulted in reduced IC50s to chemotherapeutic drugs, significantly induced G1 accumulation, inhibited growth and promoted necrosis in combination with either 5-fluorouracil (5-FU) or vincristine (VCR), and decreased the expression of ABCC1. The dual-luciferase assay demonstrated that miR-133b directly targets ABCC1. The combination of agomiRNA-133b with chemotherapeutic drugs in vivo inhibited tumor growth induced by CRC drug-resistant cells. A xenograft from the in vivo model resulted in up-regulated levels of miR-133b and down-regulated levels of ABCC1. Therefore, miR-133b enhances the chemosensitivity of CRC cells to anti-tumor drugs by directly down-regulating ABCC1. This discovery provides a therapeutic strategy in which miR-133b is used as a potential sensitizer for drug-resistant CRC.

Incidence, clinical correlates and treatment effect of rage in anxious children.

Science.gov (United States)

Johnco, Carly; Salloum, Alison; De Nadai, Alessandro S; McBride, Nicole; Crawford, Erika A; Lewin, Adam B; Storch, Eric A

2015-09-30

Episodic rage represents an important and underappreciated clinical feature in pediatric anxiety. This study examined the incidence and clinical correlates of rage in children with anxiety disorders. Change in rage during treatment for anxiety was also examined. Participants consisted of 107 children diagnosed with an anxiety disorder and their parents. Participants completed structured clinical interviews and questionnaire measures to assess rage, anxiety, functional impairment, family accommodation and caregiver strain, as well as the quality of the child's relationship with family and peers. Rage was a common feature amongst children with anxiety disorders. Rage was associated with a more severe clinical profile, including increased anxiety severity, functional impairment, family accommodation and caregiver strain, as well as poorer relationships with parents, siblings, extended family and peers. Rage was more common in children with separation anxiety, comorbid anxiety, attention deficit/hyperactivity disorder and behavioral disorders, but not depressive symptoms. Rage predicted higher levels of functional impairment, beyond the effect of anxiety severity. Rage severity reduced over treatment in line with changes in anxiety symptoms. Findings suggest that rage is a marker of greater psychopathology in anxious youth. Standard cognitive behavioral treatment for anxiety appears to reduce rage without adjunctive treatment. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Involvement of SIRT1 in hypoxic down-regulation of c-Myc and β-catenin and hypoxic preconditioning effect of polyphenols

Energy Technology Data Exchange (ETDEWEB)

Hong, Kyung-Soo [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Park, Jun-Ik [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Kim, Mi-Ju; Kim, Hak-Bong; Lee, Jae-Won [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Dao, Trong Tuan; Oh, Won Keun [BK21 Project Team, College of Pharmacy, Chosun University, Gwangju (Korea, Republic of); Kang, Chi-Dug, E-mail: kcdshbw@pusan.ac.kr [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Kim, Sun-Hee, E-mail: ksh7738@pusan.ac.kr [Department of Biochemistry, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan (Korea, Republic of)

2012-03-01

SIRT1 has been found to function as a Class III deacetylase that affects the acetylation status of histones and other important cellular nonhistone proteins involved in various cellular pathways including stress responses and apoptosis. In this study, we investigated the role of SIRT1 signaling in the hypoxic down-regulations of c-Myc and β-catenin and hypoxic preconditioning effect of the red wine polyphenols such as piceatannol, myricetin, quercetin and resveratrol. We found that the expression of SIRT1 was significantly increased in hypoxia-exposed or hypoxic preconditioned HepG2 cells, which was closely associated with the up-regulation of HIF-1α and down-regulation of c-Myc and β-catenin expression via deacetylation of these proteins. In addition, blockade of SIRT1 activation using siRNA or amurensin G, a new potent SIRT1 inhibitor, abolished hypoxia-induced HIF-1α expression but increased c-Myc and β-catenin expression. SIRT1 was also found to stabilize HIF-1α protein and destabilize c-Myc, β-catenin and PHD2 under hypoxia. We also found that myricetin, quercetin, piceatannol and resveratrol up-regulated HIF-1α and down-regulated c-Myc, PHD2 and β-catenin expressions via SIRT1 activation, in a manner that mimics hypoxic preconditioning. This study provides new insights of the molecular mechanisms of hypoxic preconditioning and suggests that polyphenolic SIRT1 activators could be used to mimic hypoxic/ischemic preconditioning. -- Graphical abstract: Polyphenols mimicked hypoxic preconditioning by up-regulating HIF-1α and SIRT1 and down-regulating c-Myc, PHD2, and β-catenin. HepG2 cells were pretreated with the indicated doses of myricetin (MYR; A), quercetin (QUR; B), or piceatannol (PIC; C) for 4 h and then exposed to hypoxia for 4 h. Levels of HIF-1α, SIRT1, c-Myc, β-catenin, and PHD2 were determined by western blot analysis. The data are representative of three individual experiments. Highlights: ► SIRT1 expression is increased in hypoxia

Involvement of SIRT1 in hypoxic down-regulation of c-Myc and β-catenin and hypoxic preconditioning effect of polyphenols

International Nuclear Information System (INIS)

Hong, Kyung-Soo; Park, Jun-Ik; Kim, Mi-Ju; Kim, Hak-Bong; Lee, Jae-Won; Dao, Trong Tuan; Oh, Won Keun; Kang, Chi-Dug; Kim, Sun-Hee

2012-01-01

SIRT1 has been found to function as a Class III deacetylase that affects the acetylation status of histones and other important cellular nonhistone proteins involved in various cellular pathways including stress responses and apoptosis. In this study, we investigated the role of SIRT1 signaling in the hypoxic down-regulations of c-Myc and β-catenin and hypoxic preconditioning effect of the red wine polyphenols such as piceatannol, myricetin, quercetin and resveratrol. We found that the expression of SIRT1 was significantly increased in hypoxia-exposed or hypoxic preconditioned HepG2 cells, which was closely associated with the up-regulation of HIF-1α and down-regulation of c-Myc and β-catenin expression via deacetylation of these proteins. In addition, blockade of SIRT1 activation using siRNA or amurensin G, a new potent SIRT1 inhibitor, abolished hypoxia-induced HIF-1α expression but increased c-Myc and β-catenin expression. SIRT1 was also found to stabilize HIF-1α protein and destabilize c-Myc, β-catenin and PHD2 under hypoxia. We also found that myricetin, quercetin, piceatannol and resveratrol up-regulated HIF-1α and down-regulated c-Myc, PHD2 and β-catenin expressions via SIRT1 activation, in a manner that mimics hypoxic preconditioning. This study provides new insights of the molecular mechanisms of hypoxic preconditioning and suggests that polyphenolic SIRT1 activators could be used to mimic hypoxic/ischemic preconditioning. -- Graphical abstract: Polyphenols mimicked hypoxic preconditioning by up-regulating HIF-1α and SIRT1 and down-regulating c-Myc, PHD2, and β-catenin. HepG2 cells were pretreated with the indicated doses of myricetin (MYR; A), quercetin (QUR; B), or piceatannol (PIC; C) for 4 h and then exposed to hypoxia for 4 h. Levels of HIF-1α, SIRT1, c-Myc, β-catenin, and PHD2 were determined by western blot analysis. The data are representative of three individual experiments. Highlights: ► SIRT1 expression is increased in hypoxia

Inhibition of HMGB1 Translocation by Green Tea Extract in Rats Exposed to Environmental Tobacco Smoke

OpenAIRE

Sirintip Chaichalotornkul; Wisuda Suvitayavat; Vanida Sangalangkarn; Yuko Nawa; Kiyoshi Kikuchi; Koichi Kawahara; Tawee Saiwichai; Somphong Narkpinit; Pratap Singhasivanon; Ikuro Maruyama; Salunya Tancharoen

2012-01-01

Environmental tobacco smoke (ETS) exposure is linked to carcinogenic, oxidative and inflammatory cellular reactions. Green tea polyphenol reportedly plays a role in the prevention of inflammation-related diseases. To evaluate the effects of green tea extract (GTE) on cellular location of High Mobility Group Box-1 (HMGB1) protein, we studied the lung tissue in rats exposed to cigarette smoke (CS). Rats were divided into three groups; CS, CSG, and C, which were groups of CS-treated only, CS-tre...

Niemann-Pick C1 like 1 gene expression is down-regulated by LXR activators in the intestine

International Nuclear Information System (INIS)

Duval, Caroline; Touche, Veronique; Tailleux, Anne; Fruchart, Jean-Charles; Fievet, Catherine; Clavey, Veronique; Staels, Bart; Lestavel, Sophie

2006-01-01

Niemann-Pick C1 like 1 (NPC1L1) is a protein critical for intestinal cholesterol absorption. The nuclear receptors peroxisome proliferator-activated receptor alpha (PPARα) and liver X receptors (LXRα and LXRβ) are major regulators of cholesterol homeostasis and their activation results in a reduced absorption of intestinal cholesterol. The goal of this study was to define the role of PPARα and LXR nuclear receptors in the regulation of NPC1L1 gene expression. We show that LXR activators down-regulate NPC1L1 mRNA levels in the human enterocyte cell line Caco-2/TC7, whereas PPARα ligands have no effect. Furthermore, NPC1L1 mRNA levels are decreased in vivo, in duodenum of mice treated with the LXR agonist T0901317. In conclusion, the present study identifies NPC1L1 as a novel LXR target gene further supporting a crucial role of LXR in intestinal cholesterol homeostasis

Escape of HIV-1-infected dendritic cells from TRAIL-mediated NK cell cytotoxicity during NK-DC cross-talk--a pivotal role of HMGB1.

Directory of Open Access Journals (Sweden)

Marie-Thérèse Melki

2010-04-01

Full Text Available Early stages of Human Immunodeficiency Virus-1 (HIV-1 infection are associated with local recruitment and activation of important effectors of innate immunity, i.e. natural killer (NK cells and dendritic cells (DCs. Immature DCs (iDCs capture HIV-1 through specific receptors and can disseminate the infection to lymphoid tissues following their migration, which is associated to a maturation process. This process is dependent on NK cells, whose role is to keep in check the quality and the quantity of DCs undergoing maturation. If DC maturation is inappropriate, NK cells will kill them ("editing process" at sites of tissue inflammation, thus optimizing the adaptive immunity. In the context of a viral infection, NK-dependent killing of infected-DCs is a crucial event required for early elimination of infected target cells. Here, we report that NK-mediated editing of iDCs is impaired if DCs are infected with HIV-1. We first addressed the question of the mechanisms involved in iDC editing, and we show that cognate NK-iDC interaction triggers apoptosis via the TNF-related apoptosis-inducing ligand (TRAIL-Death Receptor 4 (DR4 pathway and not via the perforin pathway. Nevertheless, once infected with HIV-1, DC(HIV become resistant to NK-induced TRAIL-mediated apoptosis. This resistance occurs despite normal amounts of TRAIL released by NK cells and comparable DR4 expression on DC(HIV. The escape of DC(HIV from NK killing is due to the upregulation of two anti-apoptotic molecules, the cellular-Flice like inhibitory protein (c-FLIP and the cellular inhibitor of apoptosis 2 (c-IAP2, induced by NK-DC(HIV cognate interaction. High-mobility group box 1 (HMGB1, an alarmin and a key mediator of NK-DC cross-talk, was found to play a pivotal role in NK-dependent upregulation of c-FLIP and c-IAP2 in DC(HIV. Finally, we demonstrate that restoration of DC(HIV susceptibility to NK-induced TRAIL killing can be obtained either by silencing c-FLIP and c-IAP2 by specific

Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

Energy Technology Data Exchange (ETDEWEB)

Matsui, Takanori [Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume (Japan); Yamagishi, Sho-ichi, E-mail: shoichi@med.kurume-u.ac.jp [Department of Pathophysiology and Therapeutics of Diabetic Vascular Complications, Kurume University School of Medicine, Kurume (Japan); Takeuchi, Masayoshi [Department of Pathophysiological Science, Faculty of Pharmaceutical Science, Hokuriku University, Kanazawa (Japan); Ueda, Seiji; Fukami, Kei; Okuda, Seiya [Department of Medicine, Kurume University School of Medicine, Kurume (Japan)

2010-07-23

Research highlights: {yields} Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma}. {yields} GW9662 treatment alone increased RAGE mRNA levels in tubular cells. {yields} Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-{beta} gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenic reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression

Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

International Nuclear Information System (INIS)

Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

2010-01-01

Research highlights: → Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ. → GW9662 treatment alone increased RAGE mRNA levels in tubular cells. → Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-κB activation and increases in intercellular adhesion molecule-1 and transforming growth factor-β gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenic reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPARγ). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-κB activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression via PPARγ activation.

Peripheral and central mediators of lipopolysaccharide induced suppression of defensive rage behavior in the cat.

Science.gov (United States)

Bhatt, S; Bhatt, R S; Zalcman, S S; Siegel, A

2009-11-10

Based upon recent findings in our laboratory that cytokines microinjected into the medial hypothalamus or periaqueductal gray (PAG) powerfully modulate defensive rage behavior in cat, the present study determined the effects of peripherally released cytokines following lipopolysaccharide (LPS) challenge upon defensive rage. The study involved initial identification of the effects of peripheral administration of LPS upon defensive rage by electrical stimulation from PAG and subsequent determination of the peripheral and central mechanisms governing this process. The results revealed significant elevation in response latencies for defensive rage from 60 to 300 min, post LPS injection, with no detectable signs of sickness behavior present at 60 min. In contrast, head turning behavior elicited by stimulation of adjoining midbrain sites was not affected by LPS administration, suggesting a specificity of the effects of LPS upon defensive rage. Direct administration of LPS into the medial hypothalamus had no effect on defensive rage, suggesting that the effects of LPS were mediated by peripheral cytokines rather than by any direct actions upon hypothalamic neurons. Complete blockade of the suppressive effects of LPS by peripheral pretreatment with an Anti-tumor necrosis factor-alpha (TNFalpha) antibody but not with an anti- interleukin-1 (IL-1) antibody demonstrated that the effects of LPS were mediated through TNF-alpha rather than through an IL-1 mechanism. A determination of the central mechanisms governing LPS suppression revealed that pretreatment of the medial hypothalamus with PGE(2) or 5-HT(1A) receptor antagonists each completely blocked the suppressive effects of LPS, while microinjections of a TNF-alpha antibody into the medial hypothalamus were ineffective. Microinjections of -Iodo-N-[2-[4-(methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) benzamide monohydrochloride (p-MPPI) into lateral hypothalamus (to test for anatomical specificity) had no effect upon

Vascular barrier protective effects of baicalin, baicalein and wogonin in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Kwak, Soyoung [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Korean Medicine, Daegu Haany University, Gyeongsan 712-715 (Korea, Republic of); Han, Min-Su [Laboratory for Arthritis and Bone Biology, Fatima Research Institute, Fatima Hospital, Daegu 701-600 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2014-11-15

Inhibition of high mobility group box 1 (HMGB1) protein and restoration of endothelial integrity is emerging as an attractive therapeutic strategy in the management of sepsis. Here, three structurally related polyphenols found in the Chinese herb Huang Qui, baicalin (BCL), baicalein (BCN), and wogonin (WGN), were examined for their effects on lipopolysaccharide (LPS)- or cecal ligation and puncture (CLP)-mediated release of HMGB1 and on modulation of HMGB1-mediated inflammatory responses. According to our data, BCL, BCN, and WGN inhibited the release of HMGB1 and down-regulated HMGB1-dependent inflammatory responses in human endothelial cells. BCL, BCN, and WGN also inhibited HMGB1-mediated hyperpermeability and leukocyte migration in mice. In addition, treatment with BCL, BCN, and WGN reduced CLP-induced release of HMGB1 and sepsis-related mortality and pulmonary injury in mice. These results indicate that BCL, BCN, and WGN could be candidate therapeutic agents for various severe vascular inflammatory diseases owing to their inhibition of the HMGB1 signaling pathway. - Highlights: • HMGB1 is an inflammatory mediator for vascular inflammation. • Baicalin, baicalein and wogonin inhibited HMGB1-induced hyperpermeability in vitro and in vivo. • Baicalin, baicalein and wogonin inhibited HMGB1-mediated inflammatory responses. • Baicalin, baicalein and wogonin suppressed the activation of NF-κB and ERK1/2 and production of TNF-α and IL-6. • Baicalin, baicalein and wogonin prevent CLP-induced septic mortality.

Down-regulation of SFRP1 as a putative tumor suppressor gene can contribute to human hepatocellular carcinoma

International Nuclear Information System (INIS)

Huang, Jian; Zhang, Yun-Li; Teng, Xiao-Mei; Lin, Yun; Zheng, Da-Li; Yang, Peng-Yuan; Han, Ze-Guang

2007-01-01

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. SFRP1 (the secreted frizzled-related protein 1), a putative tumor suppressor gene mapped onto chromosome 8p12-p11.1, the frequent loss of heterozygosity (LOH) region in human HCC, encodes a Wingless-type (Wnt) signaling antagonist and is frequently inactivated by promoter methylation in many human cancers. However, whether the down-regulation of SFRP1 can contribute to hepatocarcinogenesis still remains unclear. We investigated the expression of SFRP1 through real time RT-PCR and immunohistochemistry staining. The cell growth and colony formation were observed as the overexpression and knockdown of SFRP1. The DNA methylation status within SFRP1 promoter was analyzed through methylation-specific PCR or bisulphate-treated DNA sequencing assays. Loss of heterozygosity was here detected with microsatellite markers. SFRP1 was significantly down-regulated in 76.1% (35/46) HCC specimens at mRNA level and in 30% (30/100) HCCs indicated by immunohistochemistry staining, as compared to adjacent non-cancerous livers. The overexpression of SFRP1 can significantly inhibit the cell growth and colony formation of YY-8103, SMMC7721, and Hep3B cells. The RNA interference against the constitutional SFRP1 in the offspring SMMC7721 cells, which were stably transfected by ectopic SFRP1, can markedly promote cell growth of these cells. LOH of both microsatellite markers D8S532 and D8SAC016868 flanking the gene locus was found in 13% (6 of 46 HCCs) and 6.5% (3 of 46 HCCs) of the informative cases, respectively, where 5 of 8 HCC specimens with LOH showed the down-regulation of SFRP1. DNA hypermethylation within SFRP1 promoter was identified in two of three HCC specimens without SFRP1 expression. Moreover, the DNA methylation of SFRP1 promoter was significantly reduced, along with the re-expression of the gene, in those HCC cell lines, Bel7404, QGY7701, and MHCC-H, as treated by DAC. Our data suggested that the

Five Conditions Commonly Used to Down-regulate Tor Complex 1 Generate Different Physiological Situations Exhibiting Distinct Requirements and Outcomes*

Science.gov (United States)

Tate, Jennifer J.; Cooper, Terrance G.

2013-01-01

Five different physiological conditions have been used interchangeably to establish the sequence of molecular events needed to achieve nitrogen-responsive down-regulation of TorC1 and its subsequent regulation of downstream reporters: nitrogen starvation, methionine sulfoximine (Msx) addition, nitrogen limitation, rapamycin addition, and leucine starvation. Therefore, we tested a specific underlying assumption upon which the interpretation of data generated by these five experimental perturbations is premised. It is that they generate physiologically equivalent outcomes with respect to TorC1, i.e. its down-regulation as reflected by TorC1 reporter responses. We tested this assumption by performing head-to-head comparisons of the requirements for each condition to achieve a common outcome for a downstream proxy of TorC1 inactivation, nuclear Gln3 localization. We demonstrate that the five conditions for down-regulating TorC1 do not elicit physiologically equivalent outcomes. Four of the methods exhibit hierarchical Sit4 and PP2A phosphatase requirements to elicit nuclear Gln3-Myc13 localization. Rapamycin treatment required Sit4 and PP2A. Nitrogen limitation and short-term nitrogen starvation required only Sit4. G1 arrest-correlated, long-term nitrogen starvation and Msx treatment required neither PP2A nor Sit4. Starving cells of leucine or treating them with leucyl-tRNA synthetase inhibitors did not elicit nuclear Gln3-Myc13 localization. These data indicate that the five commonly used nitrogen-related conditions of down-regulating TorC1 are not physiologically equivalent and minimally involve partially differing regulatory mechanisms. Further, identical requirements for Msx treatment and long-term nitrogen starvation raise the possibility that their effects are achieved through a common regulatory pathway with glutamine, a glutamate or glutamine metabolite level as the sensed metabolic signal. PMID:23935103

Ethanol extracts of black pepper or turmeric down-regulated SIRT1 protein expression in Daudi culture cells.

Science.gov (United States)

Nishimura, Yuri; Kitagishi, Yasuko; Yoshida, Hitomi; Okumura, Naoko; Matsuda, Satoru

2011-01-01

SIRT1 is a mammalian candidate molecule involved in longevity and diverse metabolic processes. The present study aimed to determine the effects of certain herbs and spices on SIRT1 expression. Human cell lines Daudi, Jurkat, U937 and K562 were cultured in RPMI-1640. Herb and spice powders were prepared and the supernatants were collected. RT-PCR was used to quantify the expression level of the gene. Protein samples were then analyzed by Western blotting. Western blotting revealed the down-regulation of SIRT1 protein expression in Daudi cells treated with extracts of black pepper or turmeric. On the other hand, the effect on the SIRT1 gene expression examined by reverse transcription polymerase chain reaction was unaltered. In conclusion, component(s) of certain herbs and spices may induce the down-regulation of SIRT1 protein.

Narcissistic rage: The Achilles’ heel of the patient with chronic physical illness

Directory of Open Access Journals (Sweden)

Thomas Hyphantis

2009-08-01

Full Text Available Thomas Hyphantis1, Augustina Almyroudi1, Vassiliki Paika1, Panagiota Goulia1, Konstantinos Arvanitakis2,31Department of Psychiatry, Medical School, University of Ioannina, Ioannina, Greece; 2Canadian Institute of Psychoanalysis, Mcgill University, Montreal, Canada; 3Departments of Philosophy and Psychiatry, Mcgill University Health Centre, Montreal, CanadaAbstract: Based on the psychoanalytic reading of Homer’s Iliad whose principal theme is “Achilles’ rage” (the semi-mortal hero invulnerable in all of his body except for his heel, hence “Achilles’ heel” has come to mean a person’s principal weakness, we aimed to assess whether “narcissistic rage” has an impact on several psychosocial variables in patients with severe physical illness across time. In 878 patients with cancer, rheumatological diseases, multiple sclerosis, inflammatory bowel disease, and glaucoma, we assessed psychological distress (SCL-90 and GHQ-28, quality of life (WHOQOL-BREF, interpersonal difficulties (IIP-40, hostility (HDHQ, and defense styles (DSQ. Narcissistic rage comprised DSQ “omnipotence” and HDHQ “extraverted hostility”. Hierarchical multiple regressions analyses were performed. We showed that, in patients with disease duration less than one year, narcissistic rage had a minor impact on psychosocial variables studied, indicating that the rage was rather part of a “normal” mourning process. On the contrary, in patients with longer disease duration, increased rates of narcissistic rage had a great impact on all outcome variables, and the opposite was true for patients with low rates of narcissistic rage, indicating that narcissistic rage constitutes actually an “Achilles’ Heel” for patients with long-term physical illness. These findings may have important clinical implications.Keywords: consultation-liaison psychiatry, psychosomatics, narcissism, physical illness, quality of life, psychological distress, personality

Lycopene inhibits regulator of calcineurin 1-mediated apoptosis by reducing oxidative stress and down-regulating Nucling in neuronal cells.

Science.gov (United States)

Lim, Seiyoung; Hwang, Sinwoo; Yu, Ji Hoon; Lim, Joo Weon; Kim, Hyeyoung

2017-05-01

Regulator of calcineurin 1 (RCAN1) is located on the Down syndrome critical region (DSCR) locus in human chromosome 21. Oxidative stress and overexpression of RCAN1 are implicated in neuronal impairment in Down's syndrome (DS) and Alzheimer's disease (AD). Serum level of lycopene, an antioxidant pigment, is low in DS and AD patients, which may be related to neuronal damage. The present study is to investigate whether lycopene inhibits apoptosis by reducing ROS levels, NF-κB activation, expression of the apoptosis regulator Nucling, cell viability, and indices of apoptosis (cytochrome c release, caspase-3 activation) in RCAN1-overexpressing neuronal cells. Cells transfected with either pcDNA or RCAN1 were treated with or without lycopene. Lycopene decreased intracellular and mitochondrial ROS levels, NF-κB activity, and Nucling expression while it reversed decrease in mitochondrial membrane potential, mitochondrial respiration, and glycolytic function in RCAN1-overexpressing cells. Lycopene inhibited cell death, DNA fragmentation, caspase-3 activation, and cytochrome c release in RCAN1-overexpressing cells. Lycopene inhibits RCAN1-mediated apoptosis by reducing ROS levels and by inhibiting NF-κB activation, Nucling induction, and the increase in apoptotic indices in neuronal cells. Consumption of lycopene-rich foods may prevent oxidative stress-associated neuronal damage in some pathologic conditions such as DS or AD. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cloning the genes and DNA binding properties of high mobility group B1 (HMGB1) proteins from the human blood flukes Schistosoma mansoni and Schistosoma japonicum

Czech Academy of Sciences Publication Activity Database

De Oliveira, F.M.B.; Da Silva, I.C.dA.; Rumjanek, F.D.; Dias-Neto, E.; Guimaraes, P.E.M.; Verjovski-Almeida, S.; Štros, Michal; Fantappié, M.R.

2006-01-01

Roč. 377, - (2006), s. 33-45 ISSN 0378-1119 R&D Projects: GA ČR(CZ) GA204/05/2031 Institutional research plan: CEZ:AV0Z50040507 Keywords : HMGB1 * Schistosoma mansoni * Schistosoma japonicum Subject RIV: BO - Biophysics Impact factor: 2.721, year: 2006

DHA down-regulates phenobarbital-induced cytochrome P450 2B1 gene expression in rat primary hepatocytes by attenuating CAR translocation

International Nuclear Information System (INIS)

Li, C.-C.; Lii, C.-K.; Liu, K.-L.; Yang, J.-J.; Chen, H.-W.

2007-01-01

The constitutive androstane receptor (CAR) plays an important role in regulating the expression of detoxifying enzymes, including cytochrome P450 2B (CYP 2B). Phenobarbital (PB) induction of human CYP 2B6 and mouse CYP 2b10 has been shown to be mediated by CAR. Our previous study showed that PB-induced CYP 2B1 expression in rat primary hepatocytes is down-regulated by both n-6 and n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA); however, the mechanism for this down-regulation by DHA was previously unknown. The objective of the present study was to determine whether change in CAR translocation is involved in the down-regulation by n-6 and n-3 PUFAs of PB-induced CYP 2B1 expression in rat primary hepatocytes. We used 100 μM arachidonic acid, linoleic acid, eicosapentaenoic acid, and DHA to test this hypothesis. PB triggered the translocation of CAR from the cytosol into the nucleus in a dose-dependent and time-dependent manner in our hepatocyte system, and the CAR distribution in rat primary hepatocytes was significantly affected by DHA. DHA treatment decreased PB-inducible accumulation of CAR in the nuclear fraction and increased it in the cytosolic fraction in a dose-dependent manner. The down-regulation of CYP 2B1 expression by DHA occurred in a dose-dependent manner, and a similar pattern was found for the nuclear accumulation of CAR. The results of immunoprecipitation showed a CAR/RXR heterodimer bound to nuclear receptor binding site 1 (NR-1) of the PB-responsive enhancer module (PBREM) of the CYP 2B1gene. The EMSA results showed that PB-induced CAR binding to NR-1 was attenuated by DHA. Taken together, these results suggest that attenuation of CAR translocation and decreased subsequent binding to NR-1 are involved in DHA's down-regulation of PB-induced CYP 2B1 expression

Down-regulation of PRKCB1 expression in Han Chinese patients with subsyndromal symptomatic depression.

Science.gov (United States)

Guo, Xiaoyun; Li, Zezhi; Zhang, Chen; Yi, Zhenghui; Li, Haozhe; Cao, Lan; Yuan, Chengmei; Hong, Wu; Wu, Zhiguo; Peng, Daihui; Chen, Jun; Xia, Weiping; Zhao, Guoqing; Wang, Fan; Yu, Shunying; Cui, Donghong; Xu, Yifeng; Golam, Chowdhury M I; Smith, Alicia K; Wang, Tong; Fang, Yiru

2015-10-01

Subsyndromal symptomatic depression (SSD) is a common disease with significant social dysfunction. However, SSD is still not well understood and the pathophysiology of it remains unclear. We classified 48 candidate genes for SSD according to our previous study into clusters and pathways using DAVID Bioinformatics Functional Annotation Tool. We further replicated the result by using real-time Quantitative PCR (qPCR) studies to examine the expression of identified genes (i.e., STAT5b, PKCB1, ABL1 and NRAS) in another group of Han Chinese patients with SSD (n = 50). We further validated the result by examining PRKCB1 expression collected from MDD patients (n = 20). To test whether a deficit in PRKCB1 expression leads to dysregulation in PRKCB1 dependent transcript networks, we tested mRNA expression levels for the remaining 44 genes out of 48 genes in SSD patients. Finally, the power of discovery was improved by incorporating information from Quantitative Trait (eQTL) analysis. The results showed that the PRCKB1 gene expression in peripheral blood mononuclear cells (PBMC) was 33.3% down-regulated in SSD patients (n = 48, t = 3.202, p = 0.002), and a more dramatic (n = 17, 49%) down-regulation in MDD patients than control (n = 49, t = 2.114, p = 0.001). We also identified 37 genes that displayed a strong correlation with PRKCB1 mRNA expression levels in SSD patients. The expression of PRKCB1 was regulated by multiple single nucleotide polymorphisms (SNPs) both at the transcript level and exon level. In conclusion, we first found a significant decrease of PRCKB1 mRNA expression in SSD, suggesting PRKCB1 might be the candidate gene and biomarker for SSD. Copyright © 2015 Elsevier Ltd. All rights reserved.

Overexpression of rice LRK1 restricts internode elongation by down-regulating OsKO2.

Science.gov (United States)

Yang, Mengfei; Qi, Weiwei; Sun, Fan; Zha, Xiaojun; Chen, Mingluan; Huang, Yunqing; Feng, Yu-Qi; Yang, Jinshui; Luo, Xiaojin

2013-01-01

Rice (Oryza sativa) has the potential to undergo rapid internodal elongation which determines plant height. Gibberellin is involved in internode elongation. Leucine-rich repeat receptor-like kinases (LRR-RLKs) are the largest subfamily of transmembrane receptor-like kinases in plants. LRR-RLKs play important functions in mediating a variety of cellular processes and regulating responses to environmental signals. LRK1, a PSK receptor homolog, is a member of the LRR-RLK family. In the present study, differences in ectopic expression of LRK1 were consistent with extent of rice internode elongation. Analyses of gene expression demonstrated that LRK1 restricts gibberellin biosynthesis during the internode elongation process by down-regulation of the gibberellin biosynthetic gene coding for ent-kaurene oxidase.

Acute secondhand smoke-induced pulmonary inflammation is diminished in RAGE knockout mice.

Science.gov (United States)

Wood, Tyler T; Winden, Duane R; Marlor, Derek R; Wright, Alex J; Jones, Cameron M; Chavarria, Michael; Rogers, Geraldine D; Reynolds, Paul R

2014-11-15

The receptor for advanced glycation end-products (RAGE) has increasingly been demonstrated to be an important modulator of inflammation in cases of pulmonary disease. Published reports involving tobacco smoke exposure have demonstrated increased expression of RAGE, its participation in proinflammatory signaling, and its role in irreversible pulmonary remodeling. The current research evaluated the in vivo effects of short-term secondhand smoke (SHS) exposure in RAGE knockout and control mice compared with identical animals exposed to room air only. Quantitative PCR, immunoblotting, and immunohistochemistry revealed elevated RAGE expression in controls after 4 wk of SHS exposure and an anticipated absence of RAGE expression in RAGE knockout mice regardless of smoke exposure. Ras activation, NF-κB activity, and cytokine elaboration were assessed to characterize the molecular basis of SHS-induced inflammation in the mouse lung. Furthermore, bronchoalveolar lavage fluid was procured from RAGE knockout and control animals for the assessment of inflammatory cells and molecules. As a general theme, inflammation coincident with leukocyte recruitment was induced by SHS exposure and significantly influenced by the availability of RAGE. These data reveal captivating information suggesting a role for RAGE signaling in lungs exposed to SHS. However, ongoing research is still warranted to fully explain roles for RAGE and other receptors in cells coping with involuntary smoke exposure for prolonged periods of time. Copyright © 2014 the American Physiological Society.

An Ultra-High Field Study of Cerebellar Pathology in Early Relapsing-Remitting Multiple Sclerosis Using MP2RAGE.

Science.gov (United States)

Fartaria, Mário João; OʼBrien, Kieran; Şorega, Alexandra; Bonnier, Guillaume; Roche, Alexis; Falkovskiy, Pavel; Krueger, Gunnar; Kober, Tobias; Bach Cuadra, Meritxell; Granziera, Cristina

2017-05-01

The aim of this study was to study focal cerebellar pathology in early stages of multiple sclerosis (MS) using ultra-high-field magnetization-prepared 2 inversion-contrast rapid gradient-echo (7T MP2RAGE). Twenty early-stage relapsing-remitting MS patients underwent an MP2RAGE acquisition at 7 T magnetic resonance imaging (MRI) (images acquired at 2 different resolutions: 0.58 × 0.58 × 0.58 mm, 7T_0.58, and 0.75 × 0.75 × 0.90 mm, 7T_0.75) and 3 T MRI (1.0 × 1.0 × 1.2 mm, 3T_1.0). Total cerebellar lesion load and volume and mean cerebellar lesion volume were compared across images using a Wilcoxon signed-rank test. Mean T1 relaxation times in lesions and normal-appearing tissue as well as contrast-to-noise ratio (CNR) measurements were also compared using a Wilcoxon signed-rank test. A multivariate analysis was applied to assess the contribution of MRI metrics to clinical performance in MS patients. Both 7T_0.58 and 7T_0.75 MP2RAGE showed significantly higher lesion load compared with 3T_1.0 MP2RAGE (P < 0.001). Plaques that were judged as leukocortical in 7T_0.75 and 3T_1.0 MP2RAGEs were instead identified as WM lesions in 7T_0.58 MP2RAGE. Cortical lesion CNR was significantly higher in MP2RAGEs at 7 T than at 3 T. Total lesion load as well as total and mean lesion volume obtained at both 7 T and 3 T MP2RAGE significantly predicted attention (P < 0.05, adjusted R = 0.5), verbal fluency (P < 0.01, adjusted R = 0.6), and motor performance (P = 0.01, adjusted R = 0.7). This study demonstrates the value of 7 T MP2RAGE to study the cerebellum in early MS patients. 7T_0.58 MP2RAGE provides a more accurate anatomical description of white and gray matter pathology compared with 7T_0.75 and 3T_1.0 MP2RAGE, likely due to the improved spatial resolution, lower partial volume effects, and higher CNR.

CCoAOMT Down-Regulation Activates Anthocyanin Biosynthesis in Petunia1

Science.gov (United States)

Shaipulah, Nur Fariza M.; Muhlemann, Joëlle K.; Woodworth, Benjamin D.; Van Moerkercke, Alex; Ramirez, Aldana A.; Haring, Michel A.; Schuurink, Robert C.

2016-01-01

Anthocyanins and volatile phenylpropenes (isoeugenol and eugenol) in petunia (Petunia hybrida) flowers have the precursor 4-coumaryl coenzyme A (CoA) in common. These phenolics are produced at different stages during flower development. Anthocyanins are synthesized during early stages of flower development and sequestered in vacuoles during the lifespan of the flowers. The production of isoeugenol and eugenol starts when flowers open and peaks after anthesis. To elucidate additional biochemical steps toward (iso)eugenol production, we cloned and characterized a caffeoyl-coenzyme A O-methyltransferase (PhCCoAOMT1) from the petals of the fragrant petunia ‘Mitchell’. Recombinant PhCCoAOMT1 indeed catalyzed the methylation of caffeoyl-CoA to produce feruloyl CoA. Silencing of PhCCoAOMT1 resulted in a reduction of eugenol production but not of isoeugenol. Unexpectedly, the transgenic plants had purple-colored leaves and pink flowers, despite the fact that cv Mitchell lacks the functional R2R3-MYB master regulator ANTHOCYANIN2 and has normally white flowers. Our results indicate that down-regulation of PhCCoAOMT1 activated the anthocyanin pathway through the R2R3-MYBs PURPLE HAZE (PHZ) and DEEP PURPLE, with predominantly petunidin accumulating. Feeding cv Mitchell flowers with caffeic acid induced PHZ expression, suggesting that the metabolic perturbation of the phenylpropanoid pathway underlies the activation of the anthocyanin pathway. Our results demonstrate a role for PhCCoAOMT1 in phenylpropene production and reveal a link between PhCCoAOMT1 and anthocyanin production. PMID:26620524

Inhibition of GLO1 in Glioblastoma Multiforme Increases DNA-AGEs, Stimulates RAGE Expression, and Inhibits Brain Tumor Growth in Orthotopic Mouse Models

Directory of Open Access Journals (Sweden)

Rahul Jandial

2018-01-01

Full Text Available Cancers that exhibit the Warburg effect may elevate expression of glyoxylase 1 (GLO1 to detoxify the toxic glycolytic byproduct methylglyoxal (MG and inhibit the formation of pro-apoptotic advanced glycation endproducts (AGEs. Inhibition of GLO1 in cancers that up-regulate glycolysis has been proposed as a therapeutic targeting strategy, but this approach has not been evaluated for glioblastoma multiforme (GBM, the most aggressive and difficult to treat malignancy of the brain. Elevated GLO1 expression in GBM was established in patient tumors and cell lines using bioinformatics tools and biochemical approaches. GLO1 inhibition in GBM cell lines and in an orthotopic xenograft GBM mouse model was examined using both small molecule and short hairpin RNA (shRNA approaches. Inhibition of GLO1 with S-(p-bromobenzyl glutathione dicyclopentyl ester (p-BrBzGSH(Cp2 increased levels of the DNA-AGE N2-1-(carboxyethyl-2′-deoxyguanosine (CEdG, a surrogate biomarker for nuclear MG exposure; substantially elevated expression of the immunoglobulin-like receptor for AGEs (RAGE; and induced apoptosis in GBM cell lines. Targeting GLO1 with shRNA similarly increased CEdG levels and RAGE expression, and was cytotoxic to glioma cells. Mice bearing orthotopic GBM xenografts treated systemically with p-BrBzGSH(Cp2 exhibited tumor regression without significant off-target effects suggesting that GLO1 inhibition may have value in the therapeutic management of these drug-resistant tumors.

Inhibition of GLO1 in Glioblastoma Multiforme Increases DNA-AGEs, Stimulates RAGE Expression, and Inhibits Brain Tumor Growth in Orthotopic Mouse Models.

Science.gov (United States)

Jandial, Rahul; Neman, Josh; Lim, Punnajit P; Tamae, Daniel; Kowolik, Claudia M; Wuenschell, Gerald E; Shuck, Sarah C; Ciminera, Alexandra K; De Jesus, Luis R; Ouyang, Ching; Chen, Mike Y; Termini, John

2018-01-30

Cancers that exhibit the Warburg effect may elevate expression of glyoxylase 1 (GLO1) to detoxify the toxic glycolytic byproduct methylglyoxal (MG) and inhibit the formation of pro-apoptotic advanced glycation endproducts (AGEs). Inhibition of GLO1 in cancers that up-regulate glycolysis has been proposed as a therapeutic targeting strategy, but this approach has not been evaluated for glioblastoma multiforme (GBM), the most aggressive and difficult to treat malignancy of the brain. Elevated GLO1 expression in GBM was established in patient tumors and cell lines using bioinformatics tools and biochemical approaches. GLO1 inhibition in GBM cell lines and in an orthotopic xenograft GBM mouse model was examined using both small molecule and short hairpin RNA (shRNA) approaches. Inhibition of GLO1 with S -( p -bromobenzyl) glutathione dicyclopentyl ester ( p- BrBzGSH(Cp)₂) increased levels of the DNA-AGE N ²-1-(carboxyethyl)-2'-deoxyguanosine (CEdG), a surrogate biomarker for nuclear MG exposure; substantially elevated expression of the immunoglobulin-like receptor for AGEs (RAGE); and induced apoptosis in GBM cell lines. Targeting GLO1 with shRNA similarly increased CEdG levels and RAGE expression, and was cytotoxic to glioma cells. Mice bearing orthotopic GBM xenografts treated systemically with p -BrBzGSH(Cp)₂ exhibited tumor regression without significant off-target effects suggesting that GLO1 inhibition may have value in the therapeutic management of these drug-resistant tumors.

Lycium barbarum L. Polysaccharide (LBP Reduces Glucose Uptake via Down-Regulation of SGLT-1 in Caco2 Cell

Directory of Open Access Journals (Sweden)

Huizhen Cai

2017-02-01

Full Text Available Lycium barbarum L. polysaccharide (LBP is prepared from Lycium barbarum L. (L. barbarum, which is a traditional Chinese medicine. LPB has been shown to have hypoglycemic effects. In order to gain some mechanistic insights on the hypoglycemic effects of LBP, we investigated the uptake of LBP and its effect on glucose absorption in the human intestinal epithelial cell line Caco2 cell. The uptake of LBP through Caco2 cell monolayer was time-dependent and was inhibited by phloridzin, a competitive inhibitor of SGLT-1. LPB decreased the absorption of glucose in Caco2 cell, and down-regulated the expression of SGLT-1. These results suggest that LBP might be transported across the human intestinal epithelium through SGLT-1 and it inhibits glucose uptake via down-regulating SGLT-1.

Thymoquinone-rich fraction nanoemulsion (TQRFNE) decreases Aβ40 and Aβ42 levels by modulating APP processing, up-regulating IDE and LRP1, and down-regulating BACE1 and RAGE in response to high fat/cholesterol diet-induced rats.

Science.gov (United States)

Ismail, Norsharina; Ismail, Maznah; Azmi, Nur Hanisah; Bakar, Muhammad Firdaus Abu; Yida, Zhang; Abdullah, Maizaton Atmadini; Basri, Hamidon

2017-11-01

Though the causes of Alzheimer's disease (AD) are yet to be understood, much evidence has suggested that excessive amyloid-β (Aβ) accumulation due to abnormal amyloid-β precursor protein (APP) processing and Aβ metabolism are crucial processes towards AD pathogenesis. Hence, approaches aiming at APP processing and Aβ metabolism are currently being actively pursued for the management of AD. Studies suggest that high cholesterol and a high fat diet have harmful effects on cognitive function and may instigate the commencement of AD pathogenesis. Despite the neuropharmacological attributes of black cumin seed (Nigella sativa) extracts and its main active compound, thymoquinone (TQ), limited records are available in relation to AD research. Nanoemulsion (NE) is exploited as drug delivery systems due to their capacity of solubilising non-polar active compounds and is widely examined for brain targeting. Herewith, the effects of thymoquinone-rich fraction nanoemulsion (TQRFNE), thymoquinone nanoemulsion (TQNE) and their counterparts' conventional emulsion in response to high fat/cholesterol diet (HFCD)-induced rats were investigated. Particularly, the Aβ generation; APP processing, β-secretase 1 (BACE1), γ-secretases of presenilin 1 (PSEN1) and presenilin 2 (PSEN2), Aβ degradation; insulin degrading enzyme (IDE), Aβ transportation; low density lipoprotein receptor-related protein 1 (LRP1) and receptor for advanced glycation end products (RAGE) were measured in brain tissues. TQRFNE reduced the brain Aβ fragment length 1-40 and 1-42 (Aβ40 and Aβ42) levels, which would attenuate the AD pathogenesis. This reduction could be due to the modulation of β- and γ-secretase enzyme activity, and the Aβ degradation and transportation in/out of the brain. The findings show the mechanistic actions of TQRFNE in response to high fat and high cholesterol diet associated to Aβ generation, degradation and transportation in the rat's brain tissue. Copyright © 2017 Elsevier

Down regulation of macrophage IFNGR1 exacerbates systemic L. monocytogenes infection.

Directory of Open Access Journals (Sweden)

Emily M Eshleman

2017-05-01

Full Text Available Interferons (IFNs target macrophages to regulate inflammation and resistance to microbial infections. The type II IFN (IFNγ acts on a cell surface receptor (IFNGR to promote gene expression that enhance macrophage inflammatory and anti-microbial activity. Type I IFNs can dampen macrophage responsiveness to IFNγ and are associated with increased susceptibility to numerous bacterial infections. The precise mechanisms responsible for these effects remain unclear. Type I IFNs silence macrophage ifngr1 transcription and thus reduce cell surface expression of IFNGR1. To test how these events might impact macrophage activation and host resistance during bacterial infection, we developed transgenic mice that express a functional FLAG-tagged IFNGR1 (fGR1 driven by a macrophage-specific promoter. Macrophages from fGR1 mice expressed physiologic levels of cell surface IFNGR1 at steady state and responded equivalently to WT C57Bl/6 macrophages when treated with IFNγ alone. However, fGR1 macrophages retained cell surface IFNGR1 and showed enhanced responsiveness to IFNγ in the presence of type I IFNs. When fGR1 mice were infected with the bacterium Listeria monocytogenes their resistance was significantly increased, despite normal type I and II IFN production. Enhanced resistance was dependent on IFNγ and associated with increased macrophage activation and antimicrobial function. These results argue that down regulation of myeloid cell IFNGR1 is an important mechanism by which type I IFNs suppress inflammatory and anti-bacterial functions of macrophages.

A multimodal RAGE-specific inhibitor reduces amyloid β–mediated brain disorder in a mouse model of Alzheimer disease

Science.gov (United States)

Deane, Rashid; Singh, Itender; Sagare, Abhay P.; Bell, Robert D.; Ross, Nathan T.; LaRue, Barbra; Love, Rachal; Perry, Sheldon; Paquette, Nicole; Deane, Richard J.; Thiyagarajan, Meenakshisundaram; Zarcone, Troy; Fritz, Gunter; Friedman, Alan E.; Miller, Benjamin L.; Zlokovic, Berislav V.

2012-01-01

In Alzheimer disease (AD), amyloid β peptide (Aβ) accumulates in plaques in the brain. Receptor for advanced glycation end products (RAGE) mediates Aβ-induced perturbations in cerebral vessels, neurons, and microglia in AD. Here, we identified a high-affinity RAGE-specific inhibitor (FPS-ZM1) that blocked Aβ binding to the V domain of RAGE and inhibited Aβ40- and Aβ42-induced cellular stress in RAGE-expressing cells in vitro and in the mouse brain in vivo. FPS-ZM1 was nontoxic to mice and readily crossed the blood-brain barrier (BBB). In aged APPsw/0 mice overexpressing human Aβ-precursor protein, a transgenic mouse model of AD with established Aβ pathology, FPS-ZM1 inhibited RAGE-mediated influx of circulating Aβ40 and Aβ42 into the brain. In brain, FPS-ZM1 bound exclusively to RAGE, which inhibited β-secretase activity and Aβ production and suppressed microglia activation and the neuroinflammatory response. Blockade of RAGE actions at the BBB and in the brain reduced Aβ40 and Aβ42 levels in brain markedly and normalized cognitive performance and cerebral blood flow responses in aged APPsw/0 mice. Our data suggest that FPS-ZM1 is a potent multimodal RAGE blocker that effectively controls progression of Aβ-mediated brain disorder and that it may have the potential to be a disease-modifying agent for AD. PMID:22406537

Expression of DIAPH1 is up-regulated in colorectal cancer and its down-regulation strongly reduces the metastatic capacity of colon carcinoma cells.

Science.gov (United States)

Lin, Yuan-Na; Izbicki, Jakob R; König, Alexandra; Habermann, Jens K; Blechner, Christine; Lange, Tobias; Schumacher, Udo; Windhorst, Sabine

2014-04-01

In most cases, metastatic colorectal cancer is not curable, thus new approaches are necessary to identify novel targets for colorectal cancer therapy. Actin-binding-proteins (ABPs) directly regulate motility of metastasising tumor cells, and for cortactin an association with colon cancer metastasis has been already shown. However, as its depletion only incompletely inhibits metastasis, additional, more suitable cellular targets have to be identified. Here we analyzed expression of the ABPs, DIAPH1, VASP, N-WASP, and fascin in comparison with cortactin and found that, besides cortactin, DIAPH1 was expressed with the highest frequency (63%) in colorectal cancer. As well as cortactin, DIAPH1 was not detectable in normal colon tissue and expression of both proteins was positively correlated with metastasis of colorectal cancer. To analyse the mechanistic role of DIAPH1 for metastasis of colon carcinoma cells in comparison with cortactin, expression of the proteins was stably down-regulated in the human colon carcinoma cell lines HT-29, HROC-24 and HCT-116. Analysis of metastasis of colon carcinoma cells in SCID mice revealed that depletion of DIAPH1 reduced metastasis 60-fold and depletion of cortactin 16-fold as compared with control cells. Most likely the stronger effect of DIAPH1 depletion on colon cancer metastasis is due to the fact that in vitro knock down of DIAPH1 impaired all steps of metastasis; adhesion, invasion and migration while down-regulation of cortactin only reduced adhesion and invasion. This very strong reducing effect of DIAPH1 depletion on colon carcinoma cell metastasis makes the protein a promising therapeutic target for individualized colorectal cancer therapy. © 2013 UICC.

The AGE-RAGE axis in an Arab population: The United Arab Emirates Healthy Futures (UAEHFS pilot study

Directory of Open Access Journals (Sweden)

Claire K. Inman

2017-12-01

Full Text Available Aims: The transformation of the United Arab Emirates (UAE from a semi-nomadic to a high income society has been accompanied by increasing rates of obesity and Type 2 diabetes mellitus. We examined if the AGE-RAGE (receptor for advanced glycation endproducts axis is associated with obesity and diabetes mellitus in the pilot phase of the UAE Healthy Futures Study (UAEHFS. Methods: 517 Emirati subjects were enrolled and plasma/serum levels of AGE, carboxy methyl lysine (CML-AGE, soluble (sRAGE and endogenous secretory (esRAGE were measured along with weight, height, waist and hip circumference (WC/HC, blood pressure, HbA1c, Vitamin D levels and routine chemistries. The relationship between the AGE-RAGE axis and obesity and diabetes mellitus was tested using proportional odds models and linear regression. Results: After covariate adjustment, AGE levels were significantly associated with diabetes status. Levels of sRAGE and esRAGE were associated with BMI and levels of sRAGE were associated with WC/HC. Conclusions: The AGE-RAGE axis is associated with diabetes status and obesity in this Arab population. Prospective serial analysis of this axis may identify predictive biomarkers of obesity and cardiometabolic dysfunction in the UAEHFS. Keywords: Advanced glycation endproducts (AGEs, Receptor for AGE (RAGE, Cohort study, Diabetes mellitus, Obesity

Total soluble and endogenous secretory receptor for advanced glycation endproducts (RAGE) in IBD.

Science.gov (United States)

Meijer, Berrie; Hoskin, Teagan; Ashcroft, Anna; Burgess, Laura; Keenan, Jacqueline I; Falvey, James; Gearry, Richard B; Day, Andrew S

2014-06-01

Recruitment and activation of neutrophils, with release of specific proteins such as S100 proteins, is a feature of inflammatory bowel disease (IBD). Soluble forms of the receptor for advanced glycation endproducts (sRAGE), and variants such as endogenous secretory (esRAGE), can act as decoy receptors by binding ligands, including S100A12. The aims of this study were to determine total sRAGE and esRAGE concentrations in patients with IBD and correlate these with C-reactive protein (CRP), endoscopic scores and clinical disease activity scores. EDTA-plasma was collected from patients undergoing colonoscopy including those with Crohn's disease (CD: n=125), ulcerative colitis (UC: n=79) and control patients without endoscopic signs of inflammation (non-IBD: n=156). Concentrations of sRAGE and esRAGE were determined by enzyme-linked immunosorbent assay and plasma CRP concentrations measured. Standard clinical disease activity and endoscopic severity scores were defined for all subjects. Plasma sRAGE concentrations were lower in UC (but not CD) than non-IBD subjects (pdefine the significance of sRAGE and esRAGE in IBD. Copyright © 2013 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.

Potentiation of NMDA receptor-dependent cell responses by extracellular high mobility group box 1 protein.

Directory of Open Access Journals (Sweden)

Marco Pedrazzi

Full Text Available BACKGROUND: Extracellular high mobility group box 1 (HMGB1 protein can operate in a synergistic fashion with different signal molecules promoting an increase of cell Ca(2+ influx. However, the mechanisms responsible for this effect of HMGB1 are still unknown. PRINCIPAL FINDINGS: Here we demonstrate that, at concentrations of agonist per se ineffective, HMGB1 potentiates the activation of the ionotropic glutamate N-methyl-D-aspartate receptor (NMDAR in isolated hippocampal nerve terminals and in a neuroblastoma cell line. This effect was abolished by the NMDA channel blocker MK-801. The HMGB1-facilitated NMDAR opening was followed by activation of the Ca(2+-dependent enzymes calpain and nitric oxide synthase in neuroblastoma cells, resulting in an increased production of NO, a consequent enhanced cell motility, and onset of morphological differentiation. We have also identified NMDAR as the mediator of HMGB1-stimulated murine erythroleukemia cell differentiation, induced by hexamethylenebisacetamide. The potentiation of NMDAR activation involved a peptide of HMGB1 located in the B box at the amino acids 130-139. This HMGB1 fragment did not overlap with binding sites for other cell surface receptors of HMGB1, such as the advanced glycation end products or the Toll-like receptor 4. Moreover, in a competition assay, the HMGB1((130-139 peptide displaced the NMDAR/HMGB1 interaction, suggesting that it comprised the molecular and functional site of HMGB1 regulating the NMDA receptor complex. CONCLUSION: We propose that the multifunctional cytokine-like molecule HMGB1 released by activated, stressed, and damaged or necrotic cells can facilitate NMDAR-mediated cell responses, both in the central nervous system and in peripheral tissues, independently of other known cell surface receptors for HMGB1.

Vagal modulation of high mobility group box-1 protein mediates electroacupuncture-induced cardioprotection in ischemia-reperfusion injury.

Science.gov (United States)

Zhang, Juan; Yong, Yue; Li, Xing; Hu, Yu; Wang, Jian; Wang, Yong-qiang; Song, Wei; Chen, Wen-ting; Xie, Jian; Chen, Xue-mei; Lv, Xin; Hou, Li-li; Wang, Ke; Zhou, Jia; Wang, Xiang-rui; Song, Jian-gang

2015-10-26

Excessive release of high mobility group box-1 (HMGB1) protein from ischemic cardiomyocytes activates inflammatory cascades and enhances myocardial injury after reperfusion. Here we report evidence that electroacupuncture of mice at Neiguan acupoints can inhibit the up-regulation of cardiac HMGB1 following myocardial ischemia and attenuate the associated inflammatory responses and myocardial injury during reperfusion. These benefits of electroacupuncture were partially reversed by administering recombinant HMGB1 to the mice, and further potentiated by administering anti-HMGB1 antibody. Electroacupuncture-induced inhibition of HMGB1 release was markedly reduced by unilateral vagotomy or administration of nicotinic receptor antagonist, but not by chemical sympathectomy. The cholinesterase inhibitor neostigmine mimicked the effects of electroacupuncture on HMGB1 release and myocardial ischemia reperfusion injury. Culture experiments with isolated neonatal cardiomyocytes showed that acetylcholine, but not noradrenaline, inhibited hypoxia-induced release of HMGB1 via a α7nAchR-dependent pathway. These results suggest that electroacupuncture acts via the vagal nerve and its nicotinic receptor-mediated signaling to inhibit HMGB1 release from ischemic cardiomyocytes. This helps attenuate pro-inflammatory responses and myocardial injury during reperfusion.

Ectodermal-neural cortex 1 down-regulates Nrf2 at the translational level.

Directory of Open Access Journals (Sweden)

Xiao-Jun Wang

Full Text Available The transcription factor Nrf2 is the master regulator of a cellular defense mechanism against environmental insults. The Nrf2-mediated antioxidant response is accomplished by the transcription of a battery of genes that encode phase II detoxifying enzymes, xenobiotic transporters, and antioxidants. Coordinated expression of these genes is critical in protecting cells from toxic and carcinogenic insults and in maintaining cellular redox homeostasis. Activation of the Nrf2 pathway is primarily controlled by Kelch-like ECH-associated protein 1 (Keap1, which is a molecular switch that turns on or off the Nrf2 signaling pathway according to intracellular redox conditions. Here we report our finding of a novel Nrf2 suppressor ectodermal-neural cortex 1 (ENC1, which is a BTB-Kelch protein and belongs to the same family as Keap1. Transient expression of ENC1 reduced steady-state levels of Nrf2 and its downstream gene expression. Although ENC1 interacted with Keap1 indirectly, the ENC1-mediated down-regulation of Nrf2 was independent of Keap1. The negative effect of ENC1 on Nrf2 was not due to a change in the stability of Nrf2 because neither proteasomal nor lysosomal inhibitors had any effects. Overexpression of ENC1 did not result in a change in the level of Nrf2 mRNA, rather, it caused a decrease in the rate of Nrf2 protein synthesis. These results demonstrate that ENC1 functions as a negative regulator of Nrf2 through suppressing Nrf2 protein translation, which adds another level of complexity in controlling the Nrf2 signaling pathway.

Comparison of loads for wind turbine down-regulation strategies

DEFF Research Database (Denmark)

Zhu, Jiangsheng; Ma, Kuichao; N. Soltani, Mohsen

2017-01-01

For wind farm active power setpoint tracking, both farm level and turbine level down regulation strategies should to be optimized. Several down regulation strategies are chosen to analyse the wind turbine load performance according to different wind speed and power reference. In this paper we...... suggest appropriate down regulation strategy to control wind turbine for active power reference tracking. we compare four different control strategies, namely Const-Ω, Const-λ, Max-Ω and Min-Ct and discuss the loads on main components and downwind speed by presenting analysis of several wind scenarios...

SENP1 attenuates the liver fibrosis through down-regulating the expression of SMAD2.

Science.gov (United States)

Wu, Linshi; Qiu, Weiqing; Sun, Jianhua; Wang, Jian

2018-01-01

To investigate whether SENP1 could play a regulating role in the liver fibrosis process, the Sprague-Dawley (SD) rats were used to establish the liver fibrosis rat models by intraperitoneally injecting with 1 ml/kg of 10% CCl 4 , while the control normal rats were injected with olive oil. Then confirmation experiments to verify the successful establishment of these models were conducted by detecting the cellular and lobular architecture, and liver function indexes using hematoxylin-eosin staining, Masson's trichrome staining and microplate method, respectively. In addition, the expression levels of fibrosis markers including collagen I, collagen III, α-SMA and TGF-β1 were inspected using quantitative real-time PCR (qRT-PCR), as well as SMAD2. Subsequently, the relative mRNA and protein level of SENP1 was also determined via qRT-PCR and western blot analysis. Next, the HSC-T6 cells of SENP1 knock-down were constructed and used to test the relative protein expression levels of α-SMA and SMAD2 in these cells. The results of hematoxylin-eosin staining, Masson's trichrome staining and microplate method turned out that the rat liver fibrosis models were constructed successfully, which was further confirmed by the increased expression of collagen I, collagen III, α-SMA and TGF-β1 in mRNA and protein level, as well as SMAD2. Then the expression of SENP1 was overexpressed in the rat liver fibrosis models induced by CCl 4 and the TGF-β1 treatment could increase the protein expression level of collagen I, collagen III and α-SMA. Lastly, the SENP1 knockdown HSC-T6 cells were successfully constructed, while the silence of SENP1 down-regulated the protein expression of α-SMA and SMAD2. In conclusion, this study provided a new regulation mechanism about the liver fibrosis process. Copyright © 2017 Elsevier Inc. All rights reserved.

The AGE-RAGE axis in an Arab population: The United Arab Emirates Healthy Futures (UAEHFS) pilot study.

Science.gov (United States)

Inman, Claire K; Aljunaibi, Abdullah; Koh, Hyunwook; Abdulle, Abdishakur; Ali, Raghib; Alnaeemi, Abdullah; Al Zaabi, Eiman; Oumeziane, Naima; Al Bastaki, Marina; Al-Houqani, Mohammed; Al-Maskari, Fatma; Al Dhaheri, Ayesha; Shah, Syed M; Abdel Wareth, Laila; Al Mahmeed, Wael; Alsafar, Habiba; Al Anouti, Fatme; Al Hosani, Ayesha; Haji, Muna; Galani, Divya; O'Connor, Matthew J; Ahn, Jiyoung; Kirchhoff, Tomas; Sherman, Scott; Hayes, Richard B; Li, Huilin; Ramasamy, Ravichandran; Schmidt, Ann Marie

2017-12-01

The transformation of the United Arab Emirates (UAE) from a semi-nomadic to a high income society has been accompanied by increasing rates of obesity and Type 2 diabetes mellitus. We examined if the AGE-RAGE (receptor for advanced glycation endproducts) axis is associated with obesity and diabetes mellitus in the pilot phase of the UAE Healthy Futures Study (UAEHFS). 517 Emirati subjects were enrolled and plasma/serum levels of AGE, carboxy methyl lysine (CML)-AGE, soluble (s)RAGE and endogenous secretory (es)RAGE were measured along with weight, height, waist and hip circumference (WC/HC), blood pressure, HbA1c, Vitamin D levels and routine chemistries. The relationship between the AGE-RAGE axis and obesity and diabetes mellitus was tested using proportional odds models and linear regression. After covariate adjustment, AGE levels were significantly associated with diabetes status. Levels of sRAGE and esRAGE were associated with BMI and levels of sRAGE were associated with WC/HC. The AGE-RAGE axis is associated with diabetes status and obesity in this Arab population. Prospective serial analysis of this axis may identify predictive biomarkers of obesity and cardiometabolic dysfunction in the UAEHFS.

Down-regulation of serum/glucocorticoid regulated kinase 1 in colorectal tumours is largely independent of promoter hypermethylation.

Directory of Open Access Journals (Sweden)

Francesca Lessi

2010-11-01

Full Text Available We have previously shown that serum/glucocorticoid regulated kinase 1 (SGK1 is down-regulated in colorectal cancers (CRC with respect to normal tissue. As hyper-methylation of promoter regions is a well-known mechanism of gene silencing in cancer, we tested whether the SGK1 promoter region was methylated in colonic tumour samples.We investigated the methylation profile of the two CpG islands present in the promoter region of SGK1 in a panel of 5 colorectal cancer cell lines by sequencing clones of bisulphite-treated DNA samples. We further confirmed our findings in a panel of 10 normal and 10 tumour colonic tissue samples of human origin. We observed CpG methylation only in the smaller and more distal CpG island in the promoter region of SGK1 in both normal and tumour samples of colonic origin. We further identified a single nucleotide polymorphism (SNP, rs1743963 which affects methylation of the corresponding CpG.Our results show that even though partial methylation of the promoter region of SGK1 is present, this does not account for the different expression levels seen between normal and tumour tissue.

Leucine zipper, down regulated in cancer-1 gene expression in prostate cancer

Science.gov (United States)

Salemi, Michele; Barone, Nunziata; La Vignera, Sandro; Condorelli, Rosita A.; Recupero, Domenico; Galia, Antonio; Fraggetta, Filippo; Aiello, Anna Maria; Pepe, Pietro; Castiglione, Roberto; Vicari, Enzo; Calogero, Aldo E.

2016-01-01

Numerous genetic alterations have been implicated in the development of prostate cancer (PCa). DNA and protein microarrays have enabled the identification of genes associated with apoptosis, which is important in PCa development. Despite the molecular mechanisms are not entirely understood, inhibition of apoptosis is a critical pathophysiological factor that contributes to the onset and progression of PCa. Leucine zipper, down-regulated in cancer 1 (LDOC-1) is a known regulator of the nuclear factor (NF)-mediated pathway of apoptosis through the inhibition of NF-κB. The present study investigated the expression of the LDOC-1 gene in LNCaP, PC-3, PNT1A and PNT2 prostate cell lines by reverse transcription-quantitative polymerase chain reaction. In addition LDOC-1 protein expression in normal prostate tissues and PCa was studied by immunohistochemistry. LDOC-1 messenger RNA resulted overexpressed in LNCaP and PC-3 PCa cell lines compared with the two normal prostate cell lines PNT1A and PNT2. The results of immunohistochemistry demonstrated a positive cytoplasmic LDOC-1 staining in all PCa and normal prostate samples, whereas no nuclear staining was observed in any sample. Furthermore, a more intense signal was evidenced in PCa samples. LDOC-1 gene overexpression in PCa suggests an activity of LDOC-1 in PCa cell lines. PMID:27698860

RAGE receptor and its soluble isoforms in diabetes mellitus complications

Directory of Open Access Journals (Sweden)

Mauren Isfer Anghebem Oliveira

2013-04-01

Full Text Available Chronic hyperglycemia, which is present in all types of diabetes, increases the formation of advanced glycation end-products (AGEs. The interaction of AGEs with receptor of advanced glycation end-products (RAGE initiates a cascade of pro-inflammatory and pro-coagulant processes that result in oxidative stress, stimulating the formation and accumulation of more AGE molecules. This cyclic process, denominated metabolic memory, may explain the persistency of diabetic vascular complications in patients with satisfactory glycemic control. The RAGE found in several cell membranes is also present in soluble isoforms (esRAGE and cRAGE, which are generated by alternative deoxyribonucleic acid splicing or by proteolytic cleavage. This review focuses on new research into these mediators as potential biomarkers for vascular complications in diabetes.

Local and systemic occurrences of HMGB1 in gnotobiotic piglets infected with E. coli O55 are related to bacterial translocation and inflammatory cytokines

Czech Academy of Sciences Publication Activity Database

Šplíchalová, Alla; Šplíchal, Igor

2012-01-01

Roč. 60, č. 3 (2012), s. 597-600 ISSN 1043-4666 R&D Projects: GA ČR GA524/09/0365 Institutional support: RVO:61388971 Keywords : HMGB1 * Enteric infection * E. coli Subject RIV: EC - Immunology Impact factor: 2.518, year: 2012

Decreased Neointimal Extracellular Matrix Formation in RAGE-Knockout Mice After Microvascular Denudation

Energy Technology Data Exchange (ETDEWEB)

Groezinger, Gerd, E-mail: gerd.groezinger@med.uni-tuebingen.de; Schmehl, Joerg, E-mail: joerg.schmehl@med.uni-tuebingen.de; Bantleon, Ruediger, E-mail: ruediger.bantleon@med.uni-tuebingen.de; Kehlbach, Rainer, E-mail: rainer.kehlbach@uni-tuebingen.de [University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Mehra, Tarun, E-mail: tarun.mehra@med.uni-tuebingen.de [University of Tuebingen, Department of Dermatology (Germany); Claussen, Claus, E-mail: gerd.groezinger@med.uni-tuebingen.de; Wiesinger, Benjamin, E-mail: benjamin.wiesinger@med.uni-tuebingen.de [University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany)

2012-12-15

Purpose: To evaluate in vivo the role of RAGE (receptor for advanced glycated end products) in the development of restenosis and neointimal proliferation in RAGE-deficient knockout (KO) mice compared with wild-type (WT) mice in an animal model. Materials and Methods: Sixteen WT and 15 RAGE-deficient mice underwent microvascular denudation of the common femoral artery under general anaesthesia. Contralateral arteries underwent a sham operation and served as controls. Four weeks after the intervention, all animals were killed, and paraformaldehyde-fixed specimens of the femoral artery were analysed with different stains (hematoxylin and eosin and Elastica van Gieson) and several different types of immunostaining (proliferating cell nuclear antigen, {alpha}-actin, collagen, von Willebrand factor, RAGE). Luminal area, area of the neointima, and area of the media were measured in all specimens. In addition, colony-formation assays were performed, and collagen production by WT smooth muscle cells (SMCs) and RAGE-KO SMCs was determined. For statistical analysis, P < 0.05 was considered statistically significant. Results: Four weeks after denudation, WT mice showed a 49.6% loss of luminal area compared with 14.9% loss of luminal area in RAGE-deficient mice (sham = 0% loss) (P < 0.001). The neointima was 18.2 (*1000 {mu}m{sup 2} [n = 15) in the WT group compared with only 8.4 (*1000 {mu}m{sup 2} [n = 16]) in the RAGE-KO group. RAGE-KO SMCs showed significantly decreased proliferation activity and production of extracellular matrix protein. Conclusion: RAGE may be shown to play a considerable role in the formation of neointima leading to restenosis after vascular injury.

Arabidopsis chromatin-associated HMGA and HMGB use different nuclear targeting signals and display highly dynamic localization within the nucleus

DEFF Research Database (Denmark)

Launholt, Dorte; Merkle, Thomas; Houben, Andreas

2006-01-01

In plants, the chromatin-associated high mobility group (HMG) proteins occur in twosubfamilies termedHMGAandHMGB.The HMGAproteins are characterized by the presence of four AT-hookDNAbinding motifs, and theHMGBproteins contain anHMG boxDNAbinding domain. As architectural factors, theHMGproteins ap......In plants, the chromatin-associated high mobility group (HMG) proteins occur in twosubfamilies termedHMGAandHMGB.The HMGAproteins are characterized by the presence of four AT-hookDNAbinding motifs, and theHMGBproteins contain anHMG boxDNAbinding domain. As architectural factors, the...... of interphase nuclei, whereas none of the proteins associate with condensed mitotic chromosomes. HMGA is targeted to the nucleus by a monopartite nuclear localization signal, while efficient nuclear accumulation of HMGB1/5 requires large portions of the basic N-terminal part of the proteins. The acidic C...

The Liver X Receptor Ligand T0901317 Down-regulates APOA5 GeneExpression through Activation of SREBP-1c

Energy Technology Data Exchange (ETDEWEB)

Jakel, Heidelinde; Nowak, Maxime; Moitrot, Emanuelle; Dehondt, Helene; Hum, Dean W.; Pennacchio, Len A.; Fruchart-Najib, Jamila; Fruchart,Jean-Charles

2004-07-23

Alterations in the expression of the recently discovered apolipoprotein A5 gene strongly affect plasma triglyceride levels. In this study, we investigated the contribution of APOA5 to the liver X-receptor (LXR) ligand mediated effect on plasma triglyceride levels.Following treatment with the LXR ligand T0901317, we found that APOA5mRNA levels were decreased in hepatoma cell lines. The observation that no down-regulation of APOA5 promoter activity was obtained by LXR-retinoid X receptor (RXR) co-transfection prompted us to explore the possible involvement of the known LXR target gene SREBP-1c (sterol regulatory element-binding protein 1c). In fact, we found that co-transfection with the active form of SREBP-1c down-regulated APOA5promoter activity in a dose-dependent manner. We then scanned the human APOA5 promoter sequence and identified two putative E-box elements that were able to bind specifically SREBP-1c in gel-shift assays and were shown to be functional by mutation analysis. Subsequent suppression of SREBP-1 mRNA through small interfering RNA interference abolished the decrease of APOA5 mRNA in response to T0901317. Finally, administration of T0901317 to hAPOA5 transgenic mice revealed a significant decrease OF APOA5 mRNA in liver tissue and circulating apolipoprotein AV protein in plasma, confirming that the described down-regulation also occurs in vivo. Taken together, our results demonstrate that APOA5 gene expression is regulated by the LXR ligand T0901317 in a negative manner through SREBP-1c. These findings may provide a new mechanism responsible for the elevation of plasma triglyceride levels by LXR ligands and support the development of selective LXR agonists, not affecting SREBP-1c, as beneficial modulators of lipid metabolism.

The receptor for advanced glycation end products (RAGE) and the lung.

LENUS (Irish Health Repository)

Buckley, Stephen T

2010-01-01

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily of cell surface molecules. As a pattern-recognition receptor capable of binding a diverse range of ligands, it is typically expressed at low levels under normal physiological conditions in the majority of tissues. In contrast, the lung exhibits high basal level expression of RAGE localised primarily in alveolar type I (ATI) cells, suggesting a potentially important role for the receptor in maintaining lung homeostasis. Indeed, disruption of RAGE levels has been implicated in the pathogenesis of a variety of pulmonary disorders including cancer and fibrosis. Furthermore, its soluble isoforms, sRAGE, which act as decoy receptors, have been shown to be a useful marker of ATI cell injury. Whilst RAGE undoubtedly plays an important role in the biology of the lung, it remains unclear as to the exact nature of this contribution under both physiological and pathological conditions.

Down-regulation of LRP1B in colon cancer promoted the growth and migration of cancer cells.

Science.gov (United States)

Wang, Zhiqiang; Sun, Peng; Gao, Chun; Chen, Ji; Li, Jun; Chen, Zhonghao; Xu, Ming; Shao, Jun; Zhang, Yunpeng; Xie, Jiang

2017-08-01

Aberrant activation of beta-catenin/TCF signaling is one of the hallmarks of colon cancer. It is of great interest to study the mechanism for the regulation of beta-catenin/TCF signaling. In this study, it was found that LRP1B was down-regulated in colon cancer tissues and inhibited the growth, migration and metastasis of colon cancer cells. The molecular mechanism study revealed that LRP1B interacted with DVL2, inhibited the interaction between DVL2 and Axin, and negatively regulated beta-catenin/TCF signaling. Taken together, our study demonstrated the suppressive roles of LRP1B in the progression of colon cancer, implicating that restoring the function of LRP1B would be a promising strategy for the treatment of colon cancer. Copyright © 2017. Published by Elsevier Inc.

Micro-RNA-128 (miRNA-128) down-regulation in glioblastoma targets ARP5 (ANGPTL6), Bmi-1 and E2F-3a, key regulators of brain cell proliferation.

Science.gov (United States)

Cui, J G; Zhao, Y; Sethi, P; Li, Y Y; Mahta, A; Culicchia, F; Lukiw, W J

2010-07-01

High density micro-RNA (miRNA) arrays, fluorescent-reporter miRNA assay and Northern miRNA dot-blot analysis show that a brain-enriched miRNA-128 is significantly down-regulated in glioblastoma multiforme (GBM) and in GBM cell lines when compared to age-matched controls. The down-regulation of miRNA-128 was found to inversely correlate with WHO tumor grade. Three bioinformatics-verified miRNA-128 targets, angiopoietin-related growth factor protein 5 (ARP5; ANGPTL6), a transcription suppressor that promotes stem cell renewal and inhibits the expression of known tumor suppressor genes involved in senescence and differentiation, Bmi-1, and a transcription factor critical for the control of cell-cycle progression, E2F-3a, were found to be up-regulated. Addition of exogenous miRNA-128 to CRL-1690 and CRL-2610 GBM cell lines (a) restored 'homeostatic' ARP5 (ANGPTL6), Bmi-1 and E2F-3a expression, and (b) significantly decreased the proliferation of CRL-1690 and CRL-2610 cell lines. Our data suggests that down-regulation of miRNA-128 may contribute to glioma and GBM, in part, by coordinately up-regulating ARP5 (ANGPTL6), Bmi-1 and E2F-3a, resulting in the proliferation of undifferentiated GBM cells.

The RAGE Game Software Components Repository for Supporting Applied Game Development

Directory of Open Access Journals (Sweden)

Krassen Stefanov

2017-09-01

Full Text Available This paper presents the architecture of the RAGE repository, which is a unique and dedicated infrastructure that provides access to a wide variety of advanced technology components for applied game development. The RAGE project, which is the principal Horizon2020 research and innovation project on applied gaming, develops up to three dozens of software components (RAGE software assets that are reusable across a wide diversity of game engines, game platforms and programming languages. The RAGE repository provides storage space for assets and their artefacts and is designed as an asset life-cycle management system for defining, publishing, updating, searching and packaging for distribution of these assets. It will be embedded in a social platform for asset developers and other users. A dedicated Asset Repository Manager provides the main functionality of the repository and its integration with other systems. Tools supporting the Asset Manager are presented and discussed. When the RAGE repository is in full operation, applied game developers will be able to easily enhance the quality of their games by including selected advanced game software assets. Making available the RAGE repository system and its variety of software assets aims to enhance the coherence and decisiveness of the applied game industry.

Down-regulation of OsSPX1 causes high sensitivity to cold and oxidative stresses in rice seedlings.

Directory of Open Access Journals (Sweden)

Chunchao Wang

Full Text Available Rice SPX domain gene, OsSPX1, plays an important role in the phosphate (Pi signaling network. Our previous work showed that constitutive overexpression of OsSPX1 in tobacco and Arabidopsis plants improved cold tolerance while also decreasing total leaf Pi. In the present study, we generated rice antisense and sense transgenic lines of OsSPX1 and found that down-regulation of OsSPX1 caused high sensitivity to cold and oxidative stresses in rice seedlings. Compared to wild-type and OsSPX1-sense transgenic lines, more hydrogen peroxide accumulated in seedling leaves of OsSPX1-antisense transgenic lines for controls, cold and methyl viologen (MV treatments. Glutathione as a ROS scavenger could protect the antisense transgenic lines from cold and MV stress. Rice whole genome GeneChip analysis showed that some oxidative-stress marker genes (e.g. glutathione S-transferase and P450s and Pi-signaling pathway related genes (e.g. OsPHO2 were significantly down-regulated by the antisense of OsSPX1. The microarray results were validated by real-time RT-PCR. Our study indicated that OsSPX1 may be involved in cross-talks between oxidative stress, cold stress and phosphate homeostasis in rice seedling leaves.

RAGE-dependent potentiation of TRPV1 currents in sensory neurons exposed to high glucose.

Science.gov (United States)

Lam, Doris; Momeni, Zeinab; Theaker, Michael; Jagadeeshan, Santosh; Yamamoto, Yasuhiko; Ianowski, Juan P; Campanucci, Verónica A

2018-01-01

Diabetes mellitus is associated with sensory abnormalities, including exacerbated responses to painful (hyperalgesia) or non-painful (allodynia) stimuli. These abnormalities are symptoms of diabetic peripheral neuropathy (DPN), which is the most common complication that affects approximately 50% of diabetic patients. Yet, the underlying mechanisms linking hyperglycemia and symptoms of DPN remain poorly understood. The transient receptor potential vanilloid 1 (TRPV1) channel plays a central role in such sensory abnormalities and shows elevated expression levels in animal models of diabetes. Here, we investigated the function of TRPV1 channels in sensory neurons cultured from the dorsal root ganglion (DRG) of neonatal mice, under control (5mM) and high glucose (25mM) conditions. After maintaining DRG neurons in high glucose for 1 week, we observed a significant increase in capsaicin (CAP)-evoked currents and CAP-evoked depolarizations, independent of TRPV1 channel expression. These functional changes were largely dependent on the expression of the receptor for Advanced Glycation End-products (RAGE), calcium influx, cytoplasmic ROS accumulation, PKC, and Src kinase activity. Like cultured neurons from neonates, mature neurons from adult mice also displayed a similar potentiation of CAP-evoked currents in the high glucose condition. Taken together, our data demonstrate that under the diabetic condition, DRG neurons are directly affected by elevated levels of glucose, independent of vascular or glial signals, and dependent on RAGE expression. These early cellular and molecular changes to sensory neurons in vitro are potential mechanisms that might contribute to sensory abnormalities that can occur in the very early stages of diabetes.

Down-Regulation of p53 by Double-Stranded RNA Modulates the Antiviral Response

Science.gov (United States)

Marques, Joao T.; Rebouillat, Dominique; Ramana, Chilakamarti V.; Murakami, Junko; Hill, Jason E.; Gudkov, Andrei; Silverman, Robert H.; Stark, George R.; Williams, Bryan R. G.

2005-01-01

p53 has been well characterized as a tumor suppressor gene, but its role in antiviral defense remains unclear. A recent report has demonstrated that p53 can be induced by interferons and is activated after vesicular stomatitis virus (VSV) infection. We observed that different nononcogenic viruses, including encephalomyocarditis virus (EMCV) and human parainfluenza virus type 3 (HPIV3), induced down-regulation of p53 in infected cells. Double-stranded RNA (dsRNA) and a mutant vaccinia virus lacking the dsRNA binding protein E3L can also induce this effect, indicating that dsRNA formed during viral infection is likely the trigger for down-regulation of p53. The mechanism of down-regulation of p53 by dsRNA relies on translation inhibition mediated by the PKR and RNase L pathways. In the absence of p53, the replication of both EMCV and HPIV3 was retarded, whereas, conversely, VSV replication was enhanced. Cell cycle analysis indicated that wild-type (WT) but not p53 knockout (KO) fibroblasts undergo an early-G1 arrest following dsRNA treatment. Moreover, in WT cells the onset of dsRNA-induced apoptosis begins after p53 levels are down-regulated, whereas p53 KO cells, which lack the early-G1 arrest, rapidly undergo apoptosis. Hence, our data suggest that the down-regulation of p53 facilitates apoptosis, thereby limiting viral replication. PMID:16103161

Interaction between tumor cell surface receptor RAGE and proteinase 3 mediates prostate cancer metastasis to bone

Science.gov (United States)

Kolonin, Mikhail G.; Sergeeva, Anna; Staquicini, Daniela I.; Smith, Tracey L.; Tarleton, Christy A.; Molldrem, Jeffrey J.; Sidman, Richard L.; Marchiò, Serena; Pasqualini, Renata; Arap, Wadih

2017-01-01

Human prostate cancer often metastasizes to bone, but the biological basis for such site-specific tropism remains largely unresolved. Recent work led us to hypothesize that this tropism may reflect pathogenic interactions between RAGE, a cell surface receptor expressed on malignant cells in advanced prostate cancer, and proteinase 3 (PR3), a serine protease present in inflammatory neutrophils and hematopoietic cells within the bone marrow microenvironment. In this study, we establish that RAGE-PR3 interaction mediates homing of prostate cancer cells to the bone marrow. PR3 bound to RAGE on the surface of prostate cancer cells in vitro, inducing tumor cell motility through a non-proteolytic signal transduction cascade involving activation and phosphorylation of ERK1/2 and JNK1. In preclinical models of experimental metastasis, ectopic expression of RAGE on human prostate cancer cells was sufficient to promote bone marrow homing within a short time frame. Our findings demonstrate how RAGE-PR3 interactions between human prostate cancer cells and the bone marrow microenvironment mediate bone metastasis during prostate cancer progression, with potential implications for prognosis and therapeutic intervention. PMID:28428279

Structural Characterization of Lignin in Wild-Type versus COMT Down-Regulated Switchgrass

Energy Technology Data Exchange (ETDEWEB)

Samuel, Reichel [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States); Pu, Yunqiao, E-mail: yunqiao.pu@ipst.gatech.edu [BioEnergy Science Center, Oak Ridge, TN (United States); Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA (United States); Jiang, Nan [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States); Fu, Chunxiang [Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, OK (United States); Wang, Zeng-Yu [BioEnergy Science Center, Oak Ridge, TN (United States); Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, OK (United States); Ragauskas, Arthur, E-mail: yunqiao.pu@ipst.gatech.edu [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States)

2014-01-20

This study examined the chemical structural characteristics of cellulolytic enzyme lignin isolated from switchgrass focusing on comparisons between wild-type control and caffeic acid 3-O-methyltransferase (COMT) down-regulated transgenic line. Nuclear magnetic resonance techniques including {sup 13}C, {sup 31}P, and two-dimensional {sup 13}C-{sup 1}H heteronuclear single quantum coherence as well as gel permeation chromatography were employed. Compared to the wild-type, the COMT down-regulated transgenic switchgrass lignin demonstrated a decrease in syringyl (S):guaiacyl (G) ratio and p-coumarate:ferulate ratio, an increase in relative abundance of phenylcoumaran unit, and a comparable content of total free phenolic OH groups along with formation of benzodioxane unit. In addition, COMT down-regulation had no significant effects on the lignin molecular weights during its biosynthesis process.

Francisella tularensis elicits IL-10 via a PGE₂-inducible factor, to drive macrophage MARCH1 expression and class II down-regulation.

Directory of Open Access Journals (Sweden)

Danielle Hunt

Full Text Available Francisella tularensis is a bacterial pathogen that uses host-derived PGE₂ to subvert the host's adaptive immune responses in multiple ways. Francisella-induced PGE₂ acts directly on CD4 T cells to blunt production of IFN-γ. Francisella-induced PGE₂ can also elicit production of a >10 kDa soluble host factor termed FTMØSN (F. tularensismacrophage supernatant, which acts on IFN-γ pre-activated MØ to down-regulate MHC class II expression via a ubiquitin-dependent mechanism, blocking antigen presentation to CD4 T cells. Here, we report that FTMØSN-induced down-regulation of MØ class II is the result of the induction of MARCH1, and that MØ expressing MARCH1 "resistant" class II molecules are resistant to FTMØSN-induced class II down-regulation. Since PGE₂ can induce IL-10 production and IL-10 is the only reported cytokine able to induce MARCH1 expression in monocytes and dendritic cells, these findings suggested that IL-10 is the active factor in FTMØSN. However, use of IL-10 knockout MØ established that IL-10 is not the active factor in FTMØSN, but rather that Francisella-elicited PGE₂ drives production of a >10 kDa host factor distinct from IL-10. This factor then drives MØ IL-10 production to induce MARCH1 expression and the resultant class II down-regulation. Since many human pathogens such as Salmonella typhi, Mycobacterium tuberculosis and Legionella pneumophila also induce production of host PGE₂, these results suggest that a yet-to-be-identified PGE₂-inducible host factor capable of inducing IL-10 is central to the immune evasion mechanisms of multiple important human pathogens.

Frequent down-regulation of ABC transporter genes in prostate cancer

International Nuclear Information System (INIS)

Demidenko, Rita; Razanauskas, Deividas; Daniunaite, Kristina; Lazutka, Juozas Rimantas; Jankevicius, Feliksas; Jarmalaite, Sonata

2015-01-01

ATP-binding cassette (ABC) transporters are transmembrane proteins responsible for the efflux of a wide variety of substrates, including steroid metabolites, through the cellular membranes. For better characterization of the role of ABC transporters in prostate cancer (PCa) development, the profile of ABC transporter gene expression was analyzed in PCa and noncancerous prostate tissues (NPT). TaqMan Low Density Array (TLDA) human ABC transporter plates were used for the gene expression profiling in 10 PCa and 6 NPT specimens. ABCB1 transcript level was evaluated in a larger set of PCa cases (N = 78) and NPT (N = 15) by real-time PCR, the same PCa cases were assessed for the gene promoter hypermethylation by methylation-specific PCR. Expression of eight ABC transporter genes (ABCA8, ABCB1, ABCC6, ABCC9, ABCC10, ABCD2, ABCG2, and ABCG4) was significantly down-regulated in PCa as compared to NPT, and only two genes (ABCC4 and ABCG1) were up-regulated. Down-regulation of ABC transporter genes was prevalent in the TMPRSS2-ERG-negative cases. A detailed analysis of ABCB1 expression confirmed TLDA results: a reduced level of the transcript was identified in PCa in comparison to NPT (p = 0.048). Moreover, the TMPRSS2-ERG-negative PCa cases showed significantly lower expression of ABCB1 in comparison to NPT (p = 0.003) or the fusion-positive tumors (p = 0.002). Promoter methylation of ABCB1 predominantly occurred in PCa and was rarely detected in NPT (p < 0.001). The study suggests frequent down-regulation of the ABC transporter genes in PCa, especially in the TMPRSS2-ERG-negative tumors. The online version of this article (doi:10.1186/s12885-015-1689-8) contains supplementary material, which is available to authorized users

RAGE Architecture for Reusable Serious Gaming Technology Components

Directory of Open Access Journals (Sweden)

Wim van der Vegt

2016-01-01

Full Text Available For seizing the potential of serious games, the RAGE project—funded by the Horizon-2020 Programme of the European Commission—will make available an interoperable set of advanced technology components (software assets that support game studios at serious game development. This paper describes the overall software architecture and design conditions that are needed for the easy integration and reuse of such software assets in existing game platforms. Based on the component-based software engineering paradigm the RAGE architecture takes into account the portability of assets to different operating systems, different programming languages, and different game engines. It avoids dependencies on external software frameworks and minimises code that may hinder integration with game engine code. Furthermore it relies on a limited set of standard software patterns and well-established coding practices. The RAGE architecture has been successfully validated by implementing and testing basic software assets in four major programming languages (C#, C++, Java, and TypeScript/JavaScript, resp.. Demonstrator implementation of asset integration with an existing game engine was created and validated. The presented RAGE architecture paves the way for large scale development and application of cross-engine reusable software assets for enhancing the quality and diversity of serious gaming.

Emotion Regulation in Children with Down Syndrome.

Science.gov (United States)

Smith, Maureen C.; Walden, Tedra A.

This study presents a preliminary exploration of emotion regulation in a sample of 20 children (ages 3-18 years) with Down Syndrome. Three aspects of emotion regulation (modulation, organization, flexibility) were predicted from emotion variables (affect intensity, affective expression, and autonomy-curiosity and motivation) in backward regression…

Onset and organ specificity of Tk2 deficiency depends on Tk1 down-regulation and transcriptional compensation.

Science.gov (United States)

Dorado, Beatriz; Area, Estela; Akman, Hasan O; Hirano, Michio

2011-01-01

Deficiency of thymidine kinase 2 (TK2) is a frequent cause of isolated myopathy or encephalomyopathy in children with mitochondrial DNA (mtDNA) depletion. To determine the bases of disease onset, organ specificity and severity of TK2 deficiency, we have carefully characterized Tk2 H126N knockin mice (Tk2-/-). Although normal until postnatal day 8, Tk2-/- mice rapidly develop fatal encephalomyopathy between postnatal days 10 and 13. We have observed that wild-type Tk2 activity is constant in the second week of life, while Tk1 activity decreases significantly between postnatal days 8 and 13. The down-regulation of Tk1 activity unmasks Tk2 deficiency in Tk2-/- mice and correlates with the onset of mtDNA depletion in the brain and the heart. Resistance to pathology in Tk2 mutant organs depends on compensatory mechanisms to the reduced mtDNA level. Our analyses at postnatal day 13 have revealed that Tk2-/- heart significantly increases mitochondrial transcript levels relative to the mtDNA content. This transcriptional compensation allows the heart to maintain normal levels of mtDNA-encoded proteins. The up-regulation in mitochondrial transcripts is not due to increased expression of the master mitochondrial biogenesis regulators peroxisome proliferator-activated receptor-gamma coactivator 1 alpha and nuclear respiratory factors 1 and 2, or to enhanced expression of the mitochondrial transcription factors A, B1 or B2. Instead, Tk2-/- heart compensates for mtDNA depletion by down-regulating the expression of the mitochondrial transcriptional terminator transcription factor 3 (MTERF3). Understanding the molecular mechanisms that allow Tk2 mutant organs to be spared may help design therapies for Tk2 deficiency.

Inhibition of the receptor for advanced glycation end-products (RAGE) protects from secondhand smoke (SHS)-induced intrauterine growth restriction IUGR in mice.

Science.gov (United States)

Lewis, Joshua B; Mejia, Camilo; Jordan, Clinton; Monson, Troy D; Bodine, Jared S; Dunaway, Todd M; Egbert, Kaleb M; Lewis, Adam L; Wright, Tanner J; Ogden, K Connor; Broberg, Dallin S; Hall, Parker D; Nelson, Shawn M; Hirschi, Kelsey M; Reynolds, Paul R; Arroyo, Juan A

2017-12-01

Intrauterine growth restriction (IUGR) is a disease affecting 10% of all pregnancies. IUGR is associated with maternal, fetal, or placental abnormalities. Studies investigating the effects of secondhand smoke (SHS) exposure and IUGR are limited. The receptor for advanced glycation end-products (RAGE) is a pro-inflammatory transmembrane receptor increased by SHS in the placenta. We tested the hypothesis that inhibition of RAGE during SHS exposure protects from smoke-induced IUGR. C57BL/6 mice were exposed to SHS or SHS + semi-synthetic glycosaminoglycan ethers (SAGEs) known to inhibit RAGE signaling. Trophoblast cells were treated with cigarette smoke extract (CSE) with or without SAGEs in order to address the effects of RAGE inhibition during trophoblast invasion in vitro. SHS-treated mice demonstrated a significant reduction in fetal weight (7.35-fold, P ≤ 0.0001) and placental weight (1.13-fold, P ≤ 0.0001) compared with controls. Mice co-treated with SHS and SAGEs were protected from SHS-induced fetal weights decreases. SHS treatment of C57BL/6 mice activated placental extracellular signal-regulated kinase (ERK) (3.0-fold, P ≤ 0.05), JNK (2.4-fold, P ≤ 0.05) and p38 (2.1-fold, P ≤ 0.05) and the expression of inflammatory mediators including TNF-α (1.34-fold, P ≤ 0.05) and IL-1β (1.03-fold, P ≤ 0.05). SHS-mediated activation of these molecules was reduced to basal levels when SAGE was co-administered. Invasion of trophoblast cells decreased 92% (P < 0.002) when treated with CSE and CSE-mediated invasion was completely reversed by SAGEs. We conclude that RAGE inhibition protects against fetal weight loss during SHS-induced IUGR. These studies provide insight into tobacco-mediated IUGR development and clarify avenues that may be helpful in the alleviation of placental complications.

Alarmin HMGB1 is released in the small intestine of gnotobiotic piglets infected with enteric pathogens and its level in plasma reflects severity of sepsis

Czech Academy of Sciences Publication Activity Database

Šplíchalová, Alla; Šplíchal, Igor; Chmelařová, Petra; Trebichavský, Ilja

2011-01-01

Roč. 31, č. 3 (2011), s. 488-497 ISSN 0271-9142 R&D Projects: GA MŠk ME 915 Institutional research plan: CEZ:AV0Z50200510 Keywords : HMGB1 * enteric infection * cytokines Subject RIV: EE - Microbiology, Virology Impact factor: 3.077, year: 2011

CD4(+) NKG2D(+) T cells induce NKG2D down-regulation in natural killer cells in CD86-RAE-1ε transgenic mice.

Science.gov (United States)

Lin, Zhijie; Wang, Changrong; Xia, Haizui; Liu, Weiguang; Xiao, Weiming; Qian, Li; Jia, Xiaoqin; Ding, Yanbing; Ji, Mingchun; Gong, Weijuan

2014-03-01

The binding of NKG2D to its ligands strengthens the cross-talk between natural killer (NK) cells and dendritic cells, particularly at early stages, before the initiation of the adaptive immune response. We found that retinoic acid early transcript-1ε (RAE-1ε), one of the ligands of NKG2D, was persistently expressed on antigen-presenting cells in a transgenic mouse model (pCD86-RAE-1ε). By contrast, NKG2D expression on NK cells, NKG2D-dependent cytotoxicity and tumour rejection, and dextran sodium sulphate-induced colitis were all down-regulated in this mouse model. The down-regulation of NKG2D on NK cells was reversed by stimulation with poly (I:C). The ectopic expression of RAE-1ε on dendritic cells maintained NKG2D expression levels and stimulated the activity of NK cells ex vivo, but the higher frequency of CD4(+) NKG2D(+) T cells in transgenic mice led to the down-regulation of NKG2D on NK cells in vivo. Hence, high levels of RAE-1ε expression on antigen-presenting cells would be expected to induce the down-regulation of NK cell activation by a regulatory T-cell subset. © 2013 John Wiley & Sons Ltd.

Extracellular high-mobility group box 1 mediates pressure overload-induced cardiac hypertrophy and heart failure.

Science.gov (United States)

Zhang, Lei; Liu, Ming; Jiang, Hong; Yu, Ying; Yu, Peng; Tong, Rui; Wu, Jian; Zhang, Shuning; Yao, Kang; Zou, Yunzeng; Ge, Junbo

2016-03-01

Inflammation plays a key role in pressure overload-induced cardiac hypertrophy and heart failure, but the mechanisms have not been fully elucidated. High-mobility group box 1 (HMGB1), which is increased in myocardium under pressure overload, may be involved in pressure overload-induced cardiac injury. The objectives of this study are to determine the role of HMGB1 in cardiac hypertrophy and cardiac dysfunction under pressure overload. Pressure overload was imposed on the heart of male wild-type mice by transverse aortic constriction (TAC), while recombinant HMGB1, HMGB1 box A (a competitive antagonist of HMGB1) or PBS was injected into the LV wall. Moreover, cardiac myocytes were cultured and given sustained mechanical stress. Transthoracic echocardiography was performed after the operation and sections for histological analyses were generated from paraffin-embedded hearts. Relevant proteins and genes were detected. Cardiac HMGB1 expression was increased after TAC, which was accompanied by its translocation from nucleus to both cytoplasm and intercellular space. Exogenous HMGB1 aggravated TAC-induced cardiac hypertrophy and cardiac dysfunction, as demonstrated by echocardiographic analyses, histological analyses and foetal cardiac genes detection. Nevertheless, the aforementioned pathological change induced by TAC could partially be reversed by HMGB1 inhibition. Consistent with the in vivo observations, mechanical stress evoked the release and synthesis of HMGB1 in cultured cardiac myocytes. This study indicates that the activated and up-regulated HMGB1 in myocardium, which might partially be derived from cardiac myocytes under pressure overload, may be of crucial importance in pressure overload-induced cardiac hypertrophy and cardiac dysfunction. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Correlation between follicular fluid levels of sRAGE and vitamin D in women with PCOS.

Science.gov (United States)

Garg, Deepika; Grazi, Richard; Lambert-Messerlian, Geralyn M; Merhi, Zaher

2017-11-01

The pro-inflammatory advanced glycation end products (AGEs) and their anti-inflammatory soluble receptors, sRAGE, play a role in the pathogenesis of PCOS. There is a correlation between vitamin D (vit D) and sRAGE in the serum, whereby vit D replacement increases serum sRAGE levels in women with PCOS, thus incurring a protective anti-inflammatory role. This study aims to compare levels of sRAGE, N-carboxymethyl-lysine (CML; one of the AGEs), and 25-hydroxy-vit D in the follicular fluid (FF) of women with or without PCOS, and to evaluate the correlation between sRAGE and 25-hydroxy-vit D in the FF. Women with (n = 12) or without (n = 13) PCOS who underwent IVF were prospectively enrolled. Women with PCOS had significantly higher anti-Mullerian hormone levels, higher number of total retrieved and mature oocytes, and higher number of day 3 and day 5 embryos formed. Compared to women without PCOS, women with PCOS had significantly lower FF sRAGE levels. In women with PCOS, in women without PCOS, and in all participants together, there was a significant positive correlation between sRAGE and 25-hydroxy-vit D. sRAGE positively correlated with CML in women without PCOS but not in women with PCOS. In women with PCOS, the low ovarian levels of the anti-inflammatory sRAGE suggest that sRAGE could represent a biomarker and a potential therapeutic target for ovarian dysfunction in PCOS. Whether there is a direct causal relationship between sRAGE and vit D in the ovaries remains to be determined.

RAGE polymorphisms and oxidative stress levels in Hashimoto's thyroiditis.

Science.gov (United States)

Giannakou, Maria; Saltiki, Katerina; Mantzou, Emily; Loukari, Eleni; Philippou, Georgios; Terzidis, Konstantinos; Lili, Kiriaki; Stavrianos, Charalampos; Kyprianou, Miltiades; Alevizaki, Maria

2017-05-01

Polymorphisms of the receptor for advanced glycation end products (RAGE) gene have been studied in various autoimmune disorders, but not in Hashimoto's thyroiditis. Also, increased oxidative stress has been described in patients with Hashimoto's thyroiditis. The aim of this study was to investigate the possible role of two common RAGE polymorphisms (-429T>C, -374T>A) in Hashimoto's thyroiditis; in parallel, we studied oxidative stress levels. A total of 300 consecutive euthyroid women were examined and classified into three groups: Hashimoto's thyroiditis with treatment (n = 96), Hashimoto's thyroiditis without treatment (n = 109) and controls (n = 95). For a rough evaluation of oxidative stress, total lipid peroxide levels in serum were measured. The -429T>C AluI and -374T>A MfeI polymorphisms of RAGE were studied in genomic DNA. Significant association of the RAGE system with Hashimoto's thyroiditis was found only with regard to the prevalence of the -429T>C, but not with -374T>A polymorphism. The levels of oxidative stress were significantly elevated in Hashimoto's thyroiditis patients under treatment. Further analysis demonstrated that an oxidative stress cut-off value of 590 μmol/L is associated with an increased risk of progression of Hashimoto's thyroiditis from euthyroidism to hypothyroidism; this risk is further increased in carriers of the RAGE -429T>C polymorphism. Our findings indicate that both examined risk factors may be implicated in the occurrence of Hashimoto's thyroiditis, but this covers only a fraction of the pathophysiology of the disease. © 2017 Stichting European Society for Clinical Investigation Journal Foundation.

Down-regulation of telomerase activity in DLD-1 human colorectal adenocarcinoma cells by tocotrienol

International Nuclear Information System (INIS)

Eitsuka, Takahiro; Nakagawa, Kiyotaka; Miyazawa, Teruo

2006-01-01

As high telomerase activity is detected in most cancer cells, inhibition of telomerase by drug or dietary food components is a new strategy for cancer prevention. Here, we investigated the inhibitory effect of vitamin E, with particular emphasis on tocotrienol (unsaturated vitamin E), on human telomerase in cell-culture study. As results, tocotrienol inhibited telomerase activity of DLD-1 human colorectal adenocarcinoma cells in time- and dose-dependent manner, interestingly, with δ-tocotrienol exhibiting the highest inhibitory activity. Tocotrienol inhibited protein kinase C activity, resulting in down-regulation of c-myc and human telomerase reverse transcriptase (hTERT) expression, thereby reducing telomerase activity. In contrast to tocotrienol, tocopherol showed very weak telomerase inhibition. These results provide novel evidence for First time indicating that tocotrienol acts as a potent candidate regulator of telomerase and supporting the anti-proliferative function of tocotrienol

Receptor for Advanced Glycation End Products (RAGE and Its Ligands: Focus on Spinal Cord Injury

Directory of Open Access Journals (Sweden)

Juhyun Song

2014-07-01

Full Text Available Spinal cord injury (SCI results in neuronal and glial death and the loss of axons at the injury site. Inflammation after SCI leads to the inhibition of tissue regeneration and reduced neuronal survival. In addition, the loss of axons after SCI results in functional loss below the site of injury accompanied by neuronal cell body’s damage. Consequently, reducing inflammation and promoting axonal regeneration after SCI is a worthy therapeutic goal. The receptor for advanced glycation end products (RAGE is a transmembrane protein and receptor of the immunoglobulin superfamily. RAGE is implicated in inflammation and neurodegeneration. Several recent studies demonstrated an association between RAGE and central nervous system disorders through various mechanisms. However, the relationship between RAGE and SCI has not been shown. It is imperative to elucidate the association between RAGE and SCI, considering that RAGE relates to inflammation and axonal degeneration following SCI. Hence, the present review highlights recent research regarding RAGE as a compelling target for the treatment of SCI.

AS1411-Induced Growth Inhibition of Glioma Cells by Up-Regulation of p53 and Down-Regulation of Bcl-2 and Akt1 via Nucleolin.

Directory of Open Access Journals (Sweden)

Ye Cheng

Full Text Available AS1411 binds nucleolin (NCL and is the first oligodeoxynucleotide aptamer to reach phase I and II clinical trials for the treatment of several cancers. However, the mechanisms by which AS1411 targets and kills glioma cells and tissues remain unclear. Here we report that AS1411 induces cell apoptosis and cycle arrest, and inhibits cell viability by up-regulation of p53 and down-regulation of Bcl-2 and Akt1 in human glioma cells. NCL was overexpressed in both nucleus and cytoplasm in human glioma U87, U251 and SHG44 cells compared to normal human astrocytes (NHA. AS1411 bound NCL and inhibited the proliferation of glioma cells but not NHA, which was accompanied with up-regulation of p53 and down-regulation of Bcl-2 and Akt1. Moreover, AS1411 treatment resulted in the G2/M cell cycle arrest in glioma cells, which was however abolished by overexpression of NCL. Further, AS1411 induced cell apoptosis, which was prevented by silencing of p53 and overexpression of Bcl-2. In addition, AS1411 inhibited the migration and invasion of glioma cells in an Akt1-dependent manner. Importantly, AS1411 inhibited the growth of glioma xenograft and prolonged the survival time of glioma tumor-bearing mice. These results revealed a promising treatment of glioma by oligodeoxynucleotide aptamer.

CD4+ NKG2D+ T cells induce NKG2D down-regulation in natural killer cells in CD86-RAE-1ε transgenic mice

Science.gov (United States)

Lin, Zhijie; Wang, Changrong; Xia, Haizui; Liu, Weiguang; Xiao, Weiming; Qian, Li; Jia, Xiaoqin; Ding, Yanbing; Ji, Mingchun; Gong, Weijuan

2014-01-01

The binding of NKG2D to its ligands strengthens the cross-talk between natural killer (NK) cells and dendritic cells, particularly at early stages, before the initiation of the adaptive immune response. We found that retinoic acid early transcript-1ε (RAE-1ε), one of the ligands of NKG2D, was persistently expressed on antigen-presenting cells in a transgenic mouse model (pCD86-RAE-1ε). By contrast, NKG2D expression on NK cells, NKG2D-dependent cytotoxicity and tumour rejection, and dextran sodium sulphate-induced colitis were all down-regulated in this mouse model. The down-regulation of NKG2D on NK cells was reversed by stimulation with poly (I:C). The ectopic expression of RAE-1ε on dendritic cells maintained NKG2D expression levels and stimulated the activity of NK cells ex vivo, but the higher frequency of CD4+ NKG2D+ T cells in transgenic mice led to the down-regulation of NKG2D on NK cells in vivo. Hence, high levels of RAE-1ε expression on antigen-presenting cells would be expected to induce the down-regulation of NK cell activation by a regulatory T-cell subset. PMID:24708417

Narcissistic rage: The Achilles’ heel of the patient with chronic physical illness

Science.gov (United States)

Hyphantis, Thomas; Almyroudi, Augustina; Paika, Vassiliki; Goulia, Panagiota; Arvanitakis, Konstantinos

2009-01-01

Based on the psychoanalytic reading of Homer’s Iliad whose principal theme is “Achilles’ rage” (the semi-mortal hero invulnerable in all of his body except for his heel, hence “Achilles’ heel” has come to mean a person’s principal weakness), we aimed to assess whether “narcissistic rage” has an impact on several psychosocial variables in patients with severe physical illness across time. In 878 patients with cancer, rheumatological diseases, multiple sclerosis, inflammatory bowel disease, and glaucoma, we assessed psychological distress (SCL-90 and GHQ-28), quality of life (WHOQOL-BREF), interpersonal difficulties (IIP-40), hostility (HDHQ), and defense styles (DSQ). Narcissistic rage comprised DSQ “omnipotence” and HDHQ “extraverted hostility”. Hierarchical multiple regressions analyses were performed. We showed that, in patients with disease duration less than one year, narcissistic rage had a minor impact on psychosocial variables studied, indicating that the rage was rather part of a “normal” mourning process. On the contrary, in patients with longer disease duration, increased rates of narcissistic rage had a great impact on all outcome variables, and the opposite was true for patients with low rates of narcissistic rage, indicating that narcissistic rage constitutes actually an “Achilles’ Heel” for patients with long-term physical illness. These findings may have important clinical implications. PMID:19936167

The RAGE Advanced Game Technologies Repository for Supporting Applied Game Development

NARCIS (Netherlands)

Georgiev, Atanas; Grigorov, Alexander; Bontchev, Boyan; Boytchev, Pavel; Stefanov, Krassen; Westera, Wim; Prada, Rui; Hollins, Paul; Moreno Ger, Pablo

2016-01-01

This paper describes the structural architecture of the RAGE repository, which is a unique and dedicated infrastructure that provides access to a wide variety of advanced technologies (RAGE software assets) for applied game development. These software assets are reusable across a wide diversity of

Expression of receptor for advanced glycation end-products (RAGE) in thymus from myasthenia patients.

Science.gov (United States)

Bouchikh, M; Zouaidia, F; Benhaddou, E H A; Mahassini, N; Achir, A; El Malki, H O

2017-06-01

The receptor for advanced glycation end-products (RAGE) is a membranous immunoglobulin involved in the pathogenesis of numerous autoimmune diseases and tumors. The aim of this study was to investigate the possible involvement of RAGE in the pathogenesis of myasthenia gravis. This prospective study included 41 cases of myasthenia gravis treated at our institution between 2010 and 2015. There were 18 men and 23 women, with an average age of 36.44±14.47 years. The majority of patients (24.4%) were classified as IIb, according to MGFA scoring, and 21 of them required corticosteroid and/or immunosuppressive treatment. Assessment of RAGE in thymus specimens was done by immunohistochemistry using RAGE antibody (C-term). RAGE expression was assessed according to various clinical, paraclinical and pathological parameters. Histopathological studies found 18 thymomas, 17 hyperplasias and six other types of pathology. Expression of RAGE was negative/weak in 19 cases and moderate/strong in 22 cases. It was more important in thymoma type B2 (Pmyasthenia was short (P=0.04), and was not significantly related to either myasthenia clinical severity or preoperative treatment. Our results suggest that the RAGE pathway is involved in myasthenia gravis pathophysiology, especially at disease onset, and in forms with thymomas. Further studies would be indispensable to explore other aspects of this signaling pathway, especially the potential role of different ligands and soluble forms of RAGE. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

TGF-β1 stimulates migration of type II endometrial cancer cells by down-regulating PTEN via activation of SMAD and ERK1/2 signaling pathways.

Science.gov (United States)

Xiong, Siyuan; Cheng, Jung-Chien; Klausen, Christian; Zhao, Jianfang; Leung, Peter C K

2016-09-20

PTEN acts as a tumor suppressor primarily by antagonizing the PI3K/AKT signaling pathway. PTEN is frequently mutated in human cancers; however, in type II endometrial cancers its mutation rate is very low. Overexpression of TGF-β1 and its receptors has been reported to correlate with metastasis of human cancers and reduced survival rates. Although TGF-β1 has been shown to regulate PTEN expression through various mechanisms, it is not yet known if the same is true in type II endometrial cancer. In the present study, we show that treatment with TGF-β1 stimulates the migration of two type II endometrial cancer cell lines, KLE and HEC-50. In addition, TGF-β1 treatment down-regulates both mRNA and protein levels of PTEN. Overexpression of PTEN or inhibition of PI3K abolishes TGF-β1-stimulated cell migration. TGF-β1 induces SMAD2/3 phosphorylation and knockdown of common SMAD4 inhibits the suppressive effects of TGF-β1 on PTEN mRNA and protein. Interestingly, TGF-β1 induces ERK1/2 phosphorylation and pre-treatment with a MEK inhibitor attenuates the suppression of PTEN protein, but not mRNA, by TGF-β1. This study provides important insights into the molecular mechanisms mediating TGF-β1-induced down-regulation of PTEN and demonstrates an important role of PTEN in the regulation of type II endometrial cancer cell migration.

Edaravone attenuates hippocampal damage in an infant mouse model of pneumococcal meningitis by reducing HMGB1 and iNOS expression via the Nrf2/HO-1 pathway.

Science.gov (United States)

Li, Zheng; Ma, Qian-Qian; Yan, Yan; Xu, Feng-Dan; Zhang, Xiao-Ying; Zhou, Wei-Qin; Feng, Zhi-Chun

2016-09-01

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a free radical scavenger that has shown potent antioxidant, anti-inflammatory and neuroprotective effects in variety of disease models. In this study, we investigated whether edaravone produced neuroprotective actions in an infant mouse model of pneumococcal meningitis. C57BL/6 mice were infected on postnatal d 11 by intracisternal injection of a certain inoculum of Streptococcus pneumoniae. The mice received intracisternal injection of 10 μL of saline containing edaravone (3 mg/kg) once a day for 7 d. The severity of pneumococcal meningitis was assessed with a clinical score. In mice with severe meningitis, the survival rate from the time of infection to d 8 after infection was analyzed using Kaplan-Meier curves. In mice with mild meningitis, the CSF inflammation and cytokine levels in the hippocampus were analyzed d 7 after infection, and the clinical neurological deficit score was evaluated using a neurological scoring system d 14 after infection. The nuclear factor (erythroid-derived 2)-like 2 knockout (Nrf2 KO) mice and heme oxygenase-1 knockout (HO-1 KO) mice were used to confirm the involvement of Nrf2/HO-1 pathway in the neuroprotective actions of edaravone. In mice with severe meningitis, edaravone treatment significantly increased the survival rate (76.4%) compared with the meningitis model group (32.2%). In mice with mild meningitis, edaravone treatment significantly decreased the number of leukocytes and TNF- levels in CSF, as well as the neuronal apoptosis and protein levels of HMGB1 and iNOS in the hippocampus, but did not affect the high levels of IL-10 and IL-6 in the hippocampus. Moreover, edaravone treatment significantly improved the neurological function of mice with mild meningitis. In Nrf2 KO or HO-1 KO mice with the meningitis, edaravone treatment was no longer effective in improving the survival rate of the mice with severe meningitis (20.2% and 53.6%, respectively), nor it affected the

Higher plasma soluble Receptor for Advanced Glycation End Products (sRAGE) levels are associated with incident cardiovascular disease and all-cause mortality in type 1 diabetes

DEFF Research Database (Denmark)

Nin, Johanna W M; Jorsal, Anders; Ferreira, Isabel

2010-01-01

To investigate the associations of plasma levels of soluble receptor for advanced glycation end products (sRAGE) with incident cardiovascular disease (CVD) and all-cause mortality in type 1 diabetes and the extent to which any such associations could be explained by endothelial and renal dysfunct......To investigate the associations of plasma levels of soluble receptor for advanced glycation end products (sRAGE) with incident cardiovascular disease (CVD) and all-cause mortality in type 1 diabetes and the extent to which any such associations could be explained by endothelial and renal...

Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis

Directory of Open Access Journals (Sweden)

Yu-Liang Zhao

2016-01-01

Conclusion: In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.

Circulating soluble RAGE isoforms are attenuated in obese, impaired-glucose-tolerant individuals and are associated with the development of type 2 diabetes

DEFF Research Database (Denmark)

Miranda, Edwin R; Somal, Vikram S; Mey, Jacob T

2017-01-01

The soluble receptor for advanced glycation end products (sRAGE) may be protective against inflammation associated with obesity and type 2 diabetes (T2DM). The aim of this study was to determine the distribution of sRAGE isoforms and whether sRAGE isoforms are associated with risk of T2DM...... development in subjects spanning the glucose tolerance continuum. In this retrospective analysis, circulating total sRAGE and endogenous secretory RAGE (esRAGE) were quantified via ELISA, and cleaved RAGE (cRAGE) was calculated in 274 individuals stratified by glucose tolerance status (GTS) and obesity. Group......RAGE, and esRAGE were all lower with IGT and T2DM, while the ratio of cRAGE to esRAGE (cRAGE:esRAGE) was only lower (P obesity, cRAGE:esRAGE was higher with obesity and lower with IGT (P

N(epsilon)-carboxymethyllysine-modified proteins are unable to bind to RAGE and activate an inflammatory response.

Science.gov (United States)

Buetler, Timo M; Leclerc, Estelle; Baumeyer, Alexandra; Latado, Helia; Newell, John; Adolfsson, Oskar; Parisod, Véronique; Richoz, Janique; Maurer, Sarah; Foata, Francis; Piguet, Dominique; Junod, Sylviane; Heizmann, Claus W; Delatour, Thierry

2008-03-01

Advanced glycation endproducts (AGEs) containing carboxymethyllysine (CML) modifications are generally thought to be ligands of the receptor for AGEs, RAGEs. It has been argued that this results in the activation of pro-inflammatory pathways and diseases. However, it has not been shown conclusively that a CML-modified protein can interact directly with RAGE. Here, we have analyzed whether beta-lactoglobulin (bLG) or human serum albumin (HSA) modified chemically to contain only CML (10-40% lysine modification) can (i) interact with RAGE in vitro and (ii) interact with and activate RAGE in lung epithelial cells. Our results show that CML-modified bLG or HSA are unable to bind to RAGE in a cell-free assay system (Biacore). Furthermore, they are unable to activate pro-inflammatory signaling in the cellular system. Thus, CML probably does not form the necessary structure(s) to interact with RAGE and activate an inflammatory signaling cascade in RAGE-expressing cells.

Triptolide inhibits transcription of hTERT through down-regulation of transcription factor specificity protein 1 in primary effusion lymphoma cells

Energy Technology Data Exchange (ETDEWEB)

Long, Cong; Wang, Jingchao [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 (China); Guo, Wei [Department of Pathology and Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 (China); Wang, Huan; Wang, Chao; Liu, Yu [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 (China); Sun, Xiaoping, E-mail: xsun6@whu.edu.cn [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 (China); State Key Laboratory of Virology, Wuhan University, Wuhan, 430072 (China)

2016-01-01

Primary effusion lymphoma (PEL) is a rare and aggressive non-Hodgkin's lymphoma. Human telomerase reverse transcriptase (hTERT), a key component responsible for the regulation of telomerase activity, plays important roles in cellular immortalization and cancer development. Triptolide purified from Tripterygium extracts displays a broad-spectrum bioactivity profile, including immunosuppressive, anti-inflammatory, and anti-tumor. In this study, it is investigated whether triptolide reduces hTERT expression and suppresses its activity in PEL cells. The mRNA and protein levels of hTERT were examined by real time-PCR and Western blotting, respectively. The activity of hTERT promoter was determined by Dual luciferase reporter assay. Our results demonstrated that triptolide decreased expression of hTERT at both mRNA and protein levels. Further gene sequence analysis indicated that the activity of hTERT promoter was suppressed by triptolide. Triptolide also reduced the half-time of hTERT. Additionally, triptolide inhibited the expression of transcription factor specificity protein 1(Sp1) in PEL cells. Furthermore, knock-down of Sp1 by using specific shRNAs resulted in down-regulation of hTERT transcription and protein expression levels. Inhibition of Sp1 by specific shRNAs enhanced triptolide-induced cell growth inhibition and apoptosis. Collectively, our results demonstrate that the inhibitory effect of triptolide on hTERT transcription is possibly mediated by inhibition of transcription factor Sp1 in PEL cells. - Highlights: • Triptolide reduces expression of hTERT by decreasing its transcription level. • Triptolide reduces promoter activity and stability of hTERT. • Triptolide down-regulates expression of Sp1. • Special Sp1 shRNAs inhibit transcription and protein expression of hTERT. • Triptolide and Sp1 shRNA2 induce cell proliferation inhibition and apoptosis.

Bottom-up and top-down emotion generation: implications for emotion regulation

Science.gov (United States)

Misra, Supriya; Prasad, Aditya K.; Pereira, Sean C.; Gross, James J.

2012-01-01

Emotion regulation plays a crucial role in adaptive functioning and mounting evidence suggests that some emotion regulation strategies are often more effective than others. However, little attention has been paid to the different ways emotions can be generated: from the ‘bottom-up’ (in response to inherently emotional perceptual properties of the stimulus) or ‘top-down’ (in response to cognitive evaluations). Based on a process priming principle, we hypothesized that mode of emotion generation would interact with subsequent emotion regulation. Specifically, we predicted that top-down emotions would be more successfully regulated by a top-down regulation strategy than bottom-up emotions. To test this hypothesis, we induced bottom-up and top-down emotions, and asked participants to decrease the negative impact of these emotions using cognitive reappraisal. We observed the predicted interaction between generation and regulation in two measures of emotional responding. As measured by self-reported affect, cognitive reappraisal was more successful on top-down generated emotions than bottom-up generated emotions. Neurally, reappraisal of bottom-up generated emotions resulted in a paradoxical increase of amygdala activity. This interaction between mode of emotion generation and subsequent regulation should be taken into account when comparing of the efficacy of different types of emotion regulation, as well as when reappraisal is used to treat different types of clinical disorders. PMID:21296865

SKP2 siRNA inhibits the degradation of P27kip1 and down-regulates the expression of MRP in HL-60/A cells.

Science.gov (United States)

Xiao, Jie; Yin, Songmei; Li, Yiqing; Xie, Shuangfeng; Nie, Danian; Ma, Liping; Wang, Xiuju; Wu, Yudan; Feng, Jianhong

2009-08-01

S-phase kinase-associated protein 2 (SKP2) gene is a tumor suppressor gene, and is involved in the ubiquitin-mediated degradation of P27kip1. SKP2 and P27kip1 affect the proceeding and prognosis of leukemia through regulating the proliferation, apoptosis and differentiation of leukemia cells. In this study, we explored the mechanism of reversing of HL-60/A drug resistance through SKP2 down-regulation. HL-60/A cells were nucleofected by Amaxa Nucleofector System with SKP2 siRNA. The gene and protein expression levels of Skp2, P27kip1, and multi-drug resistance associated protein (MRP) were determined by reverse transcription-polymerase chain reaction and western blot analysis, respectively. The cell cycle was analyzed by flow cytometry. The 50% inhibitory concentration value was calculated using cytotoxic analysis according to the death rate of these two kinds of cells under different concentrations of chemotherapeutics to compare the sensitivity of the cells. HL-60/A cells showed multi-drug resistance phenotype characteristic by cross-resistance to adriamycin, daunorubicin, and arabinosylcytosine, due to the expression of MRP. We found that the expression of SKP2 was higher in HL-60/A cells than in HL-60 cells, but the expression of P27kip1 was lower. The expression of SKP2 in HL-60/A cells nucleofected by SKP2 siRNA was down-regulated whereas the protein level of P27kip1 was up-regulated. Compared with the MRP expression level in the control group (nucleofected by control siRNA), the mRNA and protein expression levels of MRP in HL-60/A cells nucleofected by SKP2 siRNA were lower, and the latter cells were more sensitive to adriamycin, daunorubicin, and arabinosylcytosine. Down-regulating the SKP2 expression and arresting cells in the G0/G1 phase improve drug sensitivity of leukemia cells with down-regulated MRP expression.

Plausible Roles for RAGE in Conditions Exacerbated by Direct and Indirect (Secondhand) Smoke Exposure.

Science.gov (United States)

Lewis, Joshua B; Hirschi, Kelsey M; Arroyo, Juan A; Bikman, Benjamin T; Kooyman, David L; Reynolds, Paul R

2017-03-17

Approximately 1 billion people smoke worldwide, and the burden placed on society by primary and secondhand smokers is expected to increase. Smoking is the leading risk factor for myriad health complications stemming from diverse pathogenic programs. First- and second-hand cigarette smoke contains thousands of constituents, including several carcinogens and cytotoxic chemicals that orchestrate chronic inflammatory responses and destructive remodeling events. In the current review, we outline details related to compromised pulmonary and systemic conditions related to smoke exposure. Specifically, data are discussed relative to impaired lung physiology, cancer mechanisms, maternal-fetal complications, cardiometabolic, and joint disorders in the context of smoke exposure exacerbations. As a general unifying mechanism, the receptor for advanced glycation end-products (RAGE) and its signaling axis is increasingly considered central to smoke-related pathogenesis. RAGE is a multi-ligand cell surface receptor whose expression increases following cigarette smoke exposure. RAGE signaling participates in the underpinning of inflammatory mechanisms mediated by requisite cytokines, chemokines, and remodeling enzymes. Understanding the biological contributions of RAGE during cigarette smoke-induced inflammation may provide critically important insight into the pathology of lung disease and systemic complications that combine during the demise of those exposed.

N-MYC down-regulated-like proteins regulate meristem initiation by modulating auxin transport and MAX2 expression.

Science.gov (United States)

Mudgil, Yashwanti; Ghawana, Sanjay; Jones, Alan M

2013-01-01

N-MYC down-regulated-like (NDL) proteins interact with the Gβ subunit (AGB1) of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development. Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation) confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele) mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem. NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients.

N-MYC down-regulated-like proteins regulate meristem initiation by modulating auxin transport and MAX2 expression.

Directory of Open Access Journals (Sweden)

Yashwanti Mudgil

Full Text Available N-MYC down-regulated-like (NDL proteins interact with the Gβ subunit (AGB1 of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development.Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem.NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients.