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Bai X, Wu J, Zhang M, Xu Y, Duan L, Yao K, Zhang J, Bo J, Zhao Y, Xu G, Zu H. DHCR24 Knock-Down Induced Tau Hyperphosphorylation at Thr181, Ser199, Thr231, Ser262, Ser396 Epitopes and Inhibition of Autophagy by Overactivation of GSK3β/mTOR Signaling. Front Aging Neurosci 2021; 13:513605. [PMID: 33967735 PMCID: PMC8098657 DOI: 10.3389/fnagi.2021.513605] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 02/26/2021] [Indexed: 02/01/2023] Open
Abstract
Accumulating evidences supported that knock-down of DHCR24 is linked to the pathological risk factors of AD, suggesting a potential role of DHCR24 in AD pathogenesis. However, the molecular mechanism link between DHCR24 and tauopathy remains unknown. Here, in order to elucidate the relationship between DHCR24 and tauopathy, we will focus on the effect of DHCR24 on the tau hyperphosphorylation at some toxic sites. In present study, we found that DHCR24 knock-down significantly lead to the hyperphosphorylation of tau sites at Thr181, Ser199, Thr231, Ser262, Ser396. Moreover, DHCR24 knock-down also increase the accumulation of p62 protein, simultaneously decreased the ratio of LC3-II/LC3-I and the number of autophagosome compared to the control groups, suggesting the inhibition of autophagy activity. In contrast, DHCR24 knock-in obviously abolished the effect of DHCR24 knock-down on tau hyperphosphrylation and autophagy. In addition, to elucidate the association between DHCR24 and tauopathy, we further showed that the level of plasma membrane cholesterol, lipid raft-anchored protein caveolin-1, and concomitantly total I class PI3-K (p110α), phospho-Akt (Thr308 and Ser473) were significantly decreased, resulting in the disruption of lipid raft/caveola and inhibition of PI3-K/Akt signaling in silencing DHCR24 SH-SY5Y cells compared to control groups. At the same time, DHCR24 knock-down simultaneously decreased the level of phosphorylated GSK3β at Ser9 (inactive form) and increased the level of phosphorylated mTOR at Ser2448 (active form), leading to overactivation of GSK3β and mTOR signaling. On the contrary, DHCR24 knock-in largely increased the level of membrane cholesterol and caveolin-1, suggesting the enhancement of lipid raft/caveola. And synchronously DHCR24 knock-in also abolished the effect of DHCR24 knock-down on the inhibition of PI3-K/Akt signaling as well as the overactivation of GSK3β and mTOR signaling. Collectively, our data strongly supported DHCR24 knock-down lead to tau hyperphosphorylation and the inhibition of autophagy by a lipid raft-dependent PI3-K/Akt-mediated GSK3β and mTOR signaling. Taking together, our results firstly demonstrated that the decrease of plasma membrane cholesterol mediated by DHCR24 deficiency might contribute to the tauopathy in AD and other tauopathies.
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Affiliation(s)
- Xiaojing Bai
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Junfeng Wu
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Mengqi Zhang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Yixuan Xu
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Lijie Duan
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Kai Yao
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Jianfeng Zhang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Jimei Bo
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Yongfei Zhao
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Guoxiong Xu
- The Research Center for Clinical Medicine, Jinshan Hospital, Fudan University, Shanghai, China
| | - Hengbing Zu
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
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Badran A, Baydoun E, Samaha A, Pintus G, Mesmar J, Iratni R, Issa K, Eid AH. Marjoram Relaxes Rat Thoracic Aorta Via a PI3-K/eNOS/cGMP Pathway. Biomolecules 2019; 9:biom9060227. [PMID: 31212721 PMCID: PMC6627793 DOI: 10.3390/biom9060227] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 12/28/2022] Open
Abstract
Despite pharmacotherapeutic advances, cardiovascular disease (CVD) remains the primary cause of global mortality. Alternative approaches, such as herbal medicine, continue to be sought to reduce this burden. Origanum majorana is recognized for many medicinal values, yet its vasculoprotective effects remain poorly investigated. Here, we subjected rat thoracic aortae to increasing doses of an ethanolic extract of Origanum majorana (OME). OME induced relaxation in a dose-dependent manner in endothelium-intact rings. This relaxation was significantly blunted in denuded rings. N(ω)-nitro-l-arginine methyl ester (L-NAME) or 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ) significantly reduced the OME-induced vasorelaxation. Cyclic guanosine monophosphate (cGMP) levels were also increased by OME. Moreover, wortmannin or LY294002 significantly reduced OME-induced vasorelaxation. Blockers of ATP-sensitive or Ca2+-activated potassium channels such as glibenclamide or tetraethylamonium (TEA), respectively, did not significantly affect OME-induced relaxation. Similarly, verapamil, a Ca2+ channel blocker, indomethacin, a non-selective cyclooxygenase inhibitor, and pyrilamine, a H1 histamine receptor blocker, did not significantly modulate the observed relaxation. Taken together, our results show that OME induces vasorelaxation via an endothelium-dependent mechanism involving the phosphoinositide 3-kinase (PI3-K)/ endothelial nitric oxide (NO) synthase (eNOS)/cGMP pathway. Our findings further support the medicinal value of marjoram and provide a basis for its beneficial intake. Although consuming marjoram may have an antihypertensive effect, further studies are needed to better determine its effects in different vascular beds.
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Affiliation(s)
- Adnan Badran
- Department of Nutrition, University of Petra, Amman, P.O. Box 961343 Amman 11196, Jordan.
| | - Elias Baydoun
- Department of Biology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Ali Samaha
- Department of Biomedical Sciences, Lebanese International University, Beirut, P.O. Box: 146404 Mazraa, Lebanon.
- Faculty of Public Health IV, Lebanese University, Beirut, P.O. Box 6573/14 Badaro, Lebanon.
| | - Gianfranco Pintus
- Department of Biomedical Sciences, Qatar University, Doha, P.O. Box 2713, Qatar.
- Biomedical Research Center, Qatar University, Doha, P.O. Box 2713, Qatar.
| | - Joelle Mesmar
- Department of Biology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Rabah Iratni
- Department of Biology, United Arab Emirates University, Al Ain, P.O. Box 15551, United Arab Emirates.
| | - Khodr Issa
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Ali H Eid
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
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Ye X, Zhang Y, Xu Q, Zheng H, Wu X, Qiu J, Zhang Z, Wang W, Shao Y, Xing HQ. HIV-1 Tat inhibits EAAT-2 through AEG-1 upregulation in models of HIV-associated neurocognitive disorder. Oncotarget 2017; 8:39922-34. [PMID: 28404980 DOI: 10.18632/oncotarget.16485] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 01/23/2017] [Indexed: 11/25/2022] Open
Abstract
During HIV-associated neurocognitive disorder (HAND), decreasing in excitatory amino acid transporter 2 (EAAT-2) in astrocyte plasma membranes leads to elevated levels of extracellular glutamate and, in turn, neuronal apoptosis. We used immunohistochemistry, western blot, qRT-PCR, and RNA interference to elucidate the molecular mechanisms underlying the decreased EAAT-2 expression during HAND at the tissue and cellular levels. We used simian immunodeficiency virus-human immunodeficiency virus chimeric virus (SHIV)-infected macaques as an in vivo model of HAND. Our results show that EAAT-2 expression was decreased in the cerebral cortex, while AEG-1 expression was increased, and the expression levels of these proteins were negatively correlated. In vitro analyses showed that HIV-1 Tat inhibited EAAT-2 expression by inducing overexpression of AEG-1. More specifically, HIV-1 Tat increased AEG-1 expression via the PI3-K signaling pathway, while increasing EAAT-2 inhibition by YinYan-1 (YY-1) via the NF-κB signaling pathway. These results warrant testing AEG-1 as a potential therapeutic target for treating HAND.
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Jain S, Ghanghas P, Rana C, Sanyal SN. Role of GSK-3β in Regulation of Canonical Wnt/β-catenin Signaling and PI3-K/Akt Oncogenic Pathway in Colon Cancer. Cancer Invest 2017; 35:473-483. [PMID: 28718684 DOI: 10.1080/07357907.2017.1337783] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents because of their ability in blocking cellular proliferation, and thereby tumor development, and also by promoting apoptosis. GSK-3β, a serine threonine kinase and a negative regulator of the oncogenic Wnt/β-catenin signaling pathway, plays a critical role in the regulation of oncogenesis. Celecoxib and etoricoxib, the two cyclooxygenase-2 (COX-2) selective NSAIDs, and Diclofenac, a preferential COX-2 inhibitory NSAID, had shown uniformly the chemopreventive and anti-neoplastic effects in the early stage of colon cancer by promoting apoptosis as well as an over-expression of GSK-3β while down-regulating the PI3-K/Akt oncogenic pathway.
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Affiliation(s)
- Shelly Jain
- a Department of Biophysics , Panjab University , Chandigarh , India
| | - Preety Ghanghas
- a Department of Biophysics , Panjab University , Chandigarh , India
| | - Chandan Rana
- a Department of Biophysics , Panjab University , Chandigarh , India
| | - S N Sanyal
- a Department of Biophysics , Panjab University , Chandigarh , India
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Yu J, Zheng J, Lin J, Jin L, Yu R, Mak S, Hu S, Sun H, Wu X, Zhang Z, Lee M, Tsim W, Su W, Zhou W, Cui W, Han Y, Wang Q. Indirubin-3-Oxime Prevents H 2O 2-Induced Neuronal Apoptosis via Concurrently Inhibiting GSK3β and the ERK Pathway. Cell Mol Neurobiol 2017; 37:655-64. [PMID: 27412761 DOI: 10.1007/s10571-016-0402-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 05/30/2016] [Indexed: 12/12/2022]
Abstract
Oxidative stress-induced neuronal apoptosis plays an important role in many neurodegenerative disorders. In this study, we have shown that indirubin-3-oxime, a derivative of indirubin originally designed for leukemia therapy, could prevent hydrogen peroxide (H2O2)-induced apoptosis in both SH-SY5Y cells and primary cerebellar granule neurons. H2O2 exposure led to the increased activities of glycogen synthase kinase 3β (GSK3β) and extracellular signal-regulated kinase (ERK) in SH-SY5Y cells. Indirubin-3-oxime treatment significantly reversed the altered activity of both the PI3-K/Akt/GSK3β cascade and the ERK pathway induced by H2O2. In addition, both GSK3β and mitogen-activated protein kinase inhibitors significantly prevented H2O2-induced neuronal apoptosis. Moreover, specific inhibitors of the phosphoinositide 3-kinase (PI3-K) abolished the neuroprotective effects of indirubin-3-oxime against H2O2-induced neuronal apoptosis. These results strongly suggest that indirubin-3-oxime prevents H2O2-induced apoptosis via concurrent inhibiting GSK3β and the ERK pathway in SH-SY5Y cells, providing support for the use of indirubin-3-oxime to treat neurodegenerative disorders caused or exacerbated by oxidative stress.
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Fernández-Martínez AB, Carmena MJ, Bajo AM, Vacas E, Sánchez-Chapado M, Prieto JC. VIP induces NF-κB1-nuclear localisation through different signalling pathways in human tumour and non-tumour prostate cells. Cell Signal 2014; 27:236-44. [PMID: 25446255 DOI: 10.1016/j.cellsig.2014.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 10/16/2014] [Accepted: 11/08/2014] [Indexed: 01/19/2023]
Abstract
The nuclear factor κB (NF-κB) is a powerful activator of angiogenesis, invasion and metastasis. Transactivation and nuclear localisation of NF-κB is an index of recurrence in prostate cancer. Vasoactive intestinal peptide (VIP) exerts similar effects in prostate cancer models involving increased expression of vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) which are related to NF-κB transactivation. Here we studied differential mechanisms of VIP-induced NF-κB transactivation in non-tumour RWPE-1 and tumour LNCaP and PC3 human prostate epithelial cells. Immunofluorescence studies showed that VIP increases translocation of the p50 subunit of NF-κB1 to the nucleus, an effect that was inhibited by curcumin. The signalling transduction pathways involved are different depending on cell transformation degree. In control cells (RWPE1), the effect is mediated by protein kinase A (PKA) activation and does not implicate extracellular signal-regulated kinase (ERK) or phosphoinositide 3-kinase (PI3-K) pathways whereas the opposite is true in tumour LNCaP and PC3 cells. Exchange protein directly activated by cAMP (EPAC) pathway is involved in transformed cells but not in control cells. Curcumin blocks the activating effect of VIP on COX-2 promoter/prostaglandin E2 (PGE2) production and VEGF expression and secretion. The study incorporates direct observation on COX-2 promoter and suggests that VIP effect on VEGF may be indirectly mediated by PGE2 after being synthesised by COX-2, thus amplifying the initial signal. We show that the signalling involved in VIP effects on VEGF is cAMP/PKA in non-tumour cells and cAMP/EPAC/ERK/PI3K in tumour cells which coincides with pathways mediating p50 nuclear translocation. Thus, VIP appears to use different pathways for NF-κB1 (p50) transactivation in prostate epithelial cells depending on whether they are transformed or not. Transformed cells depend on pro-survival and pro-proliferative signalling pathways involving ERK, PI3-K and cAMP/EPAC which supports the potential therapeutic value of these targets in prostate cancer.
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Affiliation(s)
- Ana B Fernández-Martínez
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - María J Carmena
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Ana M Bajo
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Eva Vacas
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Manuel Sánchez-Chapado
- Department of Surgery and Medical and Social Sciences, University of Alcalá, 28871 Alcalá de Henares, Spain; Department of Urology, Príncipe de Asturias Hospital, 28871 Alcalá de Henares, Spain
| | - Juan C Prieto
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
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Rivadeneyra L, Carestia A, Etulain J, Pozner RG, Fondevila C, Negrotto S, Schattner M. Regulation of platelet responses triggered by Toll-like receptor 2 and 4 ligands is another non-genomic role of nuclear factor-kappaB. Thromb Res 2013; 133:235-43. [PMID: 24331207 DOI: 10.1016/j.thromres.2013.11.028] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 11/06/2013] [Accepted: 11/26/2013] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Platelets express Toll-like receptors (TLRs) that recognise molecular components of pathogens and, in nucleated cells, elicit immune responses through nuclear factor-kappaB (NF-κB) activation. We have shown that NF-κB mediates platelet activation in response to classical agonists, suggesting that this transcription factor exerts non-genomic functions in platelets. The aim of this study was to determine whether NF-κB activation is a downstream signal involved in TLR2 and 4-mediated platelet responses. MATERIAL AND METHODS Aggregation and ATP release were measured with a Lumi-aggregometer. Fibrinogen binding, P-selectin and CD40 ligand (CD40L) levels and platelet-neutrophil aggregates were measured by cytometry. I kappa B alpha (IκBα) degradation and p65 phosphorylation were determined by Western blot and von Willebrand factor (vWF) by ELISA. RESULTS Platelet stimulation with Pam3CSK4 or LPS resulted in IκBα degradation and p65 phosphorylation. These responses were suppressed by TLR2 and 4 blocking and synergised by thrombin. Aggregation, fibrinogen binding and ATP and vWF release were triggered by Pam3CSK4. LPS did not induce platelet responses per se, except for vWF release, but it did potentiate thrombin-induced aggregation, fibrinogen binding and ATP secretion. Pam3CSK4, but not LPS, induced P-selectin and CD40L expression and mixed aggregate formation. All of these responses, except for CD40L expression, were inhibited in platelets treated with the NF-κB inhibitors BAY 11-7082 or Ro 106-9920. CONCLUSION TLR2 and 4 agonists trigger platelet activation responses through NF-κB. These data show another non-genomic function of NF-κB in platelets and highlight this molecule as a potential target to prevent platelet activation in inflammatory or infectious diseases.
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Affiliation(s)
- Leonardo Rivadeneyra
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina
| | - Agostina Carestia
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina
| | - Julia Etulain
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina
| | - Roberto G Pozner
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina
| | - Carlos Fondevila
- Service of Hematology, Bazterrica Clinic, Buenos Aires, Argentina
| | - Soledad Negrotto
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina
| | - Mirta Schattner
- Laboratory of Experimental Thrombosis, Institute of Experimental Medicine (CONICET), National Academy of Medicine, Buenos Aires, Argentina.
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Aoi W, Naito Y, Yoshikawa T. Role of oxidative stress in impaired insulin signaling associated with exercise-induced muscle damage. Free Radic Biol Med 2013; 65:1265-1272. [PMID: 24075894 DOI: 10.1016/j.freeradbiomed.2013.09.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 09/18/2013] [Accepted: 09/19/2013] [Indexed: 10/26/2022]
Abstract
Skeletal muscle is a major tissue that utilizes blood glucose. A single bout of exercise improves glucose uptake in skeletal muscle through insulin-dependent and insulin-independent signal transduction mechanisms. However, glucose utilization is decreased in muscle damage induced by acute, unaccustomed, or eccentric exercise. The decrease in glucose utilization is caused by decreased insulin-stimulated glucose uptake in damaged muscles with inhibition of the membrane translocation of glucose transporter 4 through phosphatidyl 3-kinase/Akt signaling. In addition to inflammatory cytokines, reactive oxygen species including 4-hydroxy-2-nonenal and peroxynitrate can induce degradation or inactivation of signaling proteins through posttranslational modification, thereby resulting in a disturbance in insulin signal transduction. In contrast, treatment with factors that attenuate oxidative stress in damaged muscle suppresses the impairment of insulin sensitivity. Muscle-damaging exercise may thus lead to decreased endurance capacity and muscle fatigue in exercise, and it may decrease the efficiency of exercise therapy for metabolic improvement.
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Affiliation(s)
- Wataru Aoi
- Laboratory of Health Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto 606-8522, Japan.
| | - Yuji Naito
- Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Toshikazu Yoshikawa
- Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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Abstract
Whereas selenium was found to act as an insulin mimic and to be antidiabetic in earlier studies, recent animal experiments and human trials have shown an unexpected risk of prolonged high Se intake in potentiating insulin resistance and type 2 diabetes. Elevating dietary Se intake (0.4 to 3.0mg/kg of diet) above the nutrient requirements, similar to overproduction of selenoproteins, led to insulin resistance and/or diabetes-like phenotypes in mice, rats, and pigs. Although its diabetogenic mechanism remains unclear, high Se intake elevated activity or production of selenoproteins including GPx1, MsrB1, SelS, and SelP. This upregulation diminished intracellular reactive oxygen species and then dysregulated key regulators of β cells and insulin synthesis and secretion, leading to chronic hyperinsulinemia. Overscavenging intracellular H2O2 also attenuated oxidative inhibition of protein tyrosine phosphatases and suppressed insulin signaling. High Se intake might affect expression and/or function of key regulators of glycolysis, gluconeogenesis, and lipogenesis. Future research is needed to find out if certain forms of Se metabolites in addition to selenoproteins and if mechanisms other than intracellular redox control mediate the diabetogenic effects of high Se intake. Furthermore, a potential interactive role of high Se intake in the interphase of carcinogenesis and diabetogenesis should be explored to make optimal use of Se in human nutrition and health.
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Affiliation(s)
- Jun Zhou
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Kaixun Huang
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xin Gen Lei
- Department of Animal Science, Cornell University, Ithaca, NY 14853, USA.
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Aroor AR, McKarns S, Demarco VG, Jia G, Sowers JR. Maladaptive immune and inflammatory pathways lead to cardiovascular insulin resistance. Metabolism 2013; 62:1543-52. [PMID: 23932846 PMCID: PMC3809332 DOI: 10.1016/j.metabol.2013.07.001] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 07/02/2013] [Accepted: 07/04/2013] [Indexed: 01/11/2023]
Abstract
Insulin resistance is a hallmark of obesity, the cardiorenal metabolic syndrome and type 2 diabetes mellitus (T2DM). The progression of insulin resistance increases the risk for cardiovascular disease (CVD). The significance of insulin resistance is underscored by the alarming rise in the prevalence of obesity and its associated comorbidities in the Unites States and worldwide over the last 40-50 years. The incidence of obesity is also on the rise in adolescents. Furthermore, premenopausal women have lower CVD risk compared to men, but this protection is lost in the setting of obesity and insulin resistance. Although systemic and cardiovascular insulin resistance is associated with impaired insulin metabolic signaling and cardiovascular dysfunction, the mechanisms underlying insulin resistance and cardiovascular dysfunction remain poorly understood. Recent studies show that insulin resistance in obesity and diabetes is linked to a metabolic inflammatory response, a state of systemic and tissue specific chronic low grade inflammation. Evidence is also emerging that there is polarization of macrophages and lymphocytes towards a pro-inflammatory phenotype that contributes to progression of insulin resistance in obesity, cardiorenal metabolic syndrome and diabetes. In this review, we provide new insights into factors, such as, the renin-angiotensin-aldosterone system, sympathetic activation and incretin modulators (e.g., DPP-4) and immune responses that mediate this inflammatory state in obesity and other conditions characterized by insulin resistance.
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Affiliation(s)
- Annayya R Aroor
- Division of Endocrinology, Diabetes and Metabolism, Diabetes Cardiovascular Center, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans Hospital, Columbia, MO, USA
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Shinozaki M, Nakamura M, Konomi T, Kobayashi Y, Takano M, Saito N, Toyama Y, Okano H. Distinct roles of endogenous vascular endothelial factor receptor 1 and 2 in neural protection after spinal cord injury. Neurosci Res 2013; 78:55-64. [PMID: 24107617 DOI: 10.1016/j.neures.2013.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/09/2013] [Accepted: 09/17/2013] [Indexed: 01/19/2023]
Abstract
Secondary degeneration after spinal cord injury (SCI) is caused by increased vascular permeability, infiltration of inflammatory cells, and subsequent focal edema. Therapeutic interventions using neurotrophic factors have focused on the prevention of such reactions to reduce cell death and promote tissue regeneration. Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor. However, the effect of VEGF on SCI remains controversial. VEGF signaling is primarily regulated through two primary receptors, VEGF receptor 1 (VEGF-R1) and VEGF receptor 2 (VEGF-R2). The purpose of this study was to examine the effects of intraperitoneal administration of VEGF-R1- and VEGF-R2-neutralizing antibodies on a mouse model of SCI. VEGF-R1 blockade, but not VEGF-R2 blockade, decreased the permeability and infiltration of inflammatory cells, and VEGF-R2 blockade caused a significant increase in neuronal apoptosis in the acute phase of SCI. VEGF-R2 blockade decreased the residual tissue area and the number of neural fibers in the chronic phase of SCI. VEGF-R2 blockade worsened the functional recovery and prolonged the latency of motor evoked potentials. These data suggest that endogenous VEGF-R2 plays a crucial role in neuronal protection after SCI.
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Affiliation(s)
- Munehisa Shinozaki
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Masaya Nakamura
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
| | - Tsunehiko Konomi
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Yoshiomi Kobayashi
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Morito Takano
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Nobuhito Saito
- Department of Neurosurgery, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Yoshiaki Toyama
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
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Schedlich LJ, Yenson VM, Baxter RC. TGF-β-induced expression of IGFBP-3 regulates IGF1R signaling in human osteosarcoma cells. Mol Cell Endocrinol 2013; 377:56-64. [PMID: 23831640 DOI: 10.1016/j.mce.2013.06.033] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 06/20/2013] [Accepted: 06/25/2013] [Indexed: 11/25/2022]
Abstract
Signaling pathways initiated by transforming growth factor-β (TGF-β) and insulin-like growth factors (IGFs) are important in osteosarcoma cell growth. We have investigated a role for endogenous IGF binding protein-3 (IGFBP-3) in mediating cross-talk between TGF-β receptor and type I IGF receptor (IGF1R) signaling pathways in MG-63 osteosarcoma cells. TGF-β1 indirectly activated the Ras/Raf/MAPK pathway and induced the expression of IGFBP-3, an important regulator of IGF1R activity. IGFBP-3 attenuated TGF-β1 activation of ERK1/2 and Akt in MG-63 cells, and inhibited TGF-β1-induced cell cycle progression and proliferation. This effect of IGFBP-3 was blocked by inhibiting IGF1R signaling. TGF-β1 phosphorylated Smad2 on the non-receptor substrate sites (Ser245/250/255). Blocking the TGF-β1-induced expression of IGFBP-3 enhanced pSmad2(Ser245/250/255) and increased its nuclear accumulation. These results suggest an important role for TGF-β1 in osteosarcoma cell growth, with the induction of IGFBP-3 by TGF-β1 serving in a negative-feedback loop to control cell growth by preventing activation of the IGF1R.
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Affiliation(s)
- Lynette J Schedlich
- Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, Sydney, NSW 2065, Australia.
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Paul AG, Chandran B, Sharma-Walia N. Cyclooxygenase-2-prostaglandin E2-eicosanoid receptor inflammatory axis: a key player in Kaposi's sarcoma-associated herpes virus associated malignancies. Transl Res 2013; 162:77-92. [PMID: 23567332 PMCID: PMC7185490 DOI: 10.1016/j.trsl.2013.03.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 02/13/2013] [Accepted: 03/15/2013] [Indexed: 12/28/2022]
Abstract
The role of cyclooxygenase-2 (COX-2), its lipid metabolite prostaglandin E2 (PGE2), and Eicosanoid (EP) receptors (EP; 1-4) underlying the proinflammatory mechanistic aspects of Burkitt's lymphoma, nasopharyngeal carcinoma, cervical cancer, prostate cancer, colon cancer, and Kaposi's sarcoma (KS) is an active area of investigation. The tumorigenic potential of COX-2 and PGE2 through EP receptors forms the mechanistic context underlying the chemotherapeutic potential of nonsteroidal anti-inflammatory drugs (NSAIDs). Although role of the COX-2 is described in several viral associated malignancies, the biological significance of the COX-2/PGE2/EP receptor inflammatory axis is extensively studied only in Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8) associated malignancies such as KS, a multifocal endothelial cell tumor and primary effusion lymphoma (PEL), a B cell-proliferative disorder. The purpose of this review is to summarize the salient findings delineating the molecular mechanisms downstream of COX-2 involving PGE2 secretion and its autocrine and paracrine interactions with EP receptors (EP1-4), COX-2/PGE2/EP receptor signaling regulating KSHV pathogenesis and latency. KSHV infection induces COX-2, PGE2 secretion, and EP receptor activation. The resulting signal cascades modulate the expression of KSHV latency genes (latency associated nuclear antigen-1 [LANA-1] and viral-Fas (TNFRSF6)-associated via death domain like interferon converting enzyme-like- inhibitory protein [vFLIP]). vFLIP was also shown to be crucial for the maintenance of COX-2 activation. The mutually interdependent interactions between viral proteins (LANA-1/vFLIP) and COX-2/PGE2/EP receptors was shown to play key roles in the biological mechanisms involved in KS and PEL pathogenesis such as blockage of apoptosis, cell cycle regulation, transformation, proliferation, angiogenesis, adhesion, invasion, and immune-suppression. Understanding the COX-2/PGE2/EP axis is very important to develop new safer and specific therapeutic modalities for KS and PEL. In addition to COX-2 being a therapeutic target, EP receptors represent ideal targets for pharmacologic agents as PGE2 analogues and their blockers/antagonists possess antineoplastic activity, without the reported gastrointestinal and cardiovascular toxicity observed with few a NSAIDs.
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MESH Headings
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Antineoplastic Agents/pharmacology
- Cyclooxygenase 2/metabolism
- Dinoprostone/metabolism
- Gene Expression Regulation, Viral
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/pathogenicity
- Humans
- Lymphoma, Primary Effusion/drug therapy
- Lymphoma, Primary Effusion/metabolism
- Receptors, Eicosanoid/metabolism
- Sarcoma, Kaposi/drug therapy
- Sarcoma, Kaposi/metabolism
- Sarcoma, Kaposi/virology
- Signal Transduction
- Virus Latency/genetics
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Affiliation(s)
- Arun George Paul
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Ill
| | - Bala Chandran
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Ill
| | - Neelam Sharma-Walia
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Ill
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Piplani H, Rana C, Vaish V, Vaiphei K, Sanyal SN. Dolastatin, along with Celecoxib, stimulates apoptosis by a mechanism involving oxidative stress, membrane potential change and PI3-K/AKT pathway down regulation. Biochim Biophys Acta Gen Subj 2013; 1830:5142-56. [PMID: 23872169 DOI: 10.1016/j.bbagen.2013.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 12/15/2022]
Abstract
BACKGROUND Phosphoinositide 3-kinase (PI3-K) is an important regulator of oncogenesis and apoptosis in various types of cancers including colon cancer. A combinatorial strategy of using Cyclooxygenase-2 inhibitor, Celecoxib and Dolastatin, a linear peptide from marine mollusks of Indian Ocean origin has shown anti-neoplastic effects in colon cancer in a rat model. METHODS The signal transduction pathway of PI3-K/AKT and the downstream signaling proteins had been studied in an early stage of colon carcinogenesis (DMH induced) by gene and protein expression, apoptotic studies by colonocyte apoptotic bleb assay, intracellular calcium level by fluorescence spectrometry, mitochondrial membrane potential by Rhodamine 123 flow cytometry and Reactive oxygen species measurement. Molecular docking analysis was employed to study the interaction of oncogenic proteins and the ligand, Celecoxib and Dolastatin. RESULTS Apoptotic cell index was lowered with DMH while both the drugs increased it and inhibited PI3-K and AKT expression. Docking studies revealed both the proteins targeted by the drugs via an ATP binding site. An increased expression of GSK-3β, pro-apoptotic protein Bad, transcription factor Egr-1, tumor suppressor protein PTEN while a downregulation of G1-associated cell cycle protein, Cyclin D1 and increased intracellular calcium as well as reactive oxygen species were observed. Also, the number of cells having a higher mitochondrial membrane potential was lowered. CONCLUSION Celecoxib and Dolastatin inhibited the tumor development through regulation of the PI3-K/AKT pathway which can act as a novel target for these drugs. GENERAL SIGNIFICANCE The anti-cancer properties of Dolastatin, a peptide isolated from marine mollusks in colorectal cancer is shown.
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Affiliation(s)
- Honit Piplani
- Department of Biophysics, Panjab University, Chandigarh 160014, India
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Panja D, Bramham CR. BDNF mechanisms in late LTP formation: A synthesis and breakdown. Neuropharmacology 2013; 76 Pt C:664-76. [PMID: 23831365 DOI: 10.1016/j.neuropharm.2013.06.024] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 06/21/2013] [Accepted: 06/23/2013] [Indexed: 12/12/2022]
Abstract
Unraveling the molecular mechanisms governing long-term synaptic plasticity is a key to understanding how the brain stores information in neural circuits and adapts to a changing environment. Brain-derived neurotrophic factor (BDNF) has emerged as a regulator of stable, late phase long-term potentiation (L-LTP) at excitatory glutamatergic synapses in the adult brain. However, the mechanisms by which BDNF triggers L-LTP are controversial. Here, we distill and discuss the latest advances along three main lines: 1) TrkB receptor-coupled translational control underlying dendritic protein synthesis and L-LTP, 2) Mechanisms for BDNF-induced rescue of L-LTP when protein synthesis is blocked, and 3) BDNF-TrkB regulation of actin cytoskeletal dynamics in dendritic spines. Finally, we explore the inter-relationships between BDNF-regulated mechanisms, how these mechanisms contribute to different forms of L-LTP in the hippocampus and dentate gyrus, and outline outstanding issues for future research. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
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Affiliation(s)
- Debabrata Panja
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway; KG Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
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Atkins RJ, Stylli SS, Luwor RB, Kaye AH, Hovens CM. Glycogen synthase kinase-3β (GSK-3β) and its dysregulation in glioblastoma multiforme. J Clin Neurosci 2013; 20:1185-92. [PMID: 23768967 DOI: 10.1016/j.jocn.2013.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 02/09/2013] [Indexed: 01/10/2023]
Abstract
Glioblastoma multiforme (GBM) is the most frequently occurring and devastating human brain malignancy, retaining almost universal mortality and a median survival of only 14 months, even with recent advances in multimodal treatments. Gliomas are characterised as being both highly resistant to chemo- and radiotherapy and highly invasive, rendering conventional interventions palliative. The continual dismal prognosis for GBM patients identifies an urgent need for the evolutionary development of new treatment modalities. This includes molecular targeted therapies as many signaling molecules and associated pathways have been implicated in the development and survival of malignant gliomas including the protein kinase, glycogen synthase kinase 3 beta (GSK-3β). Here we review the activity and function of GSK-3β in a number of signaling pathways and its role in gliomagenesis.
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Affiliation(s)
- R J Atkins
- Department of Surgery, The University of Melbourne, The Royal Melbourne Hospital, Grattan Street, Parkville, VIC 3050, Australia.
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Leal G, Comprido D, Duarte CB. BDNF-induced local protein synthesis and synaptic plasticity. Neuropharmacology 2013; 76 Pt C:639-56. [PMID: 23602987 DOI: 10.1016/j.neuropharm.2013.04.005] [Citation(s) in RCA: 416] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/25/2013] [Accepted: 04/03/2013] [Indexed: 12/16/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is an important regulator of synaptic transmission and long-term potentiation (LTP) in the hippocampus and in other brain regions, playing a role in the formation of certain forms of memory. The effects of BDNF in LTP are mediated by TrkB (tropomyosin-related kinase B) receptors, which are known to be coupled to the activation of the Ras/ERK, phosphatidylinositol 3-kinase/Akt and phospholipase C-γ (PLC-γ) pathways. The role of BDNF in LTP is best studied in the hippocampus, where the neurotrophin acts at pre- and post-synaptic levels. Recent studies have shown that BDNF regulates the transport of mRNAs along dendrites and their translation at the synapse, by modulating the initiation and elongation phases of protein synthesis, and by acting on specific miRNAs. Furthermore, the effect of BDNF on transcription regulation may further contribute to long-term changes in the synaptic proteome. In this review we discuss the recent progress in understanding the mechanisms contributing to the short- and long-term regulation of the synaptic proteome by BDNF, and the role in synaptic plasticity, which is likely to influence learning and memory formation. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
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Affiliation(s)
- Graciano Leal
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal
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Kim KH, Yang CS, Shin AR, Jeon SR, Park JK, Kim HJ, Jo EK. Mycobacterial Heparin-binding Hemagglutinin Antigen Activates Inflammatory Responses through PI3-K/Akt, NF-κB, and MAPK Pathways. Immune Netw 2011; 11:123-33. [PMID: 21637390 PMCID: PMC3100523 DOI: 10.4110/in.2011.11.2.123] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 04/04/2011] [Accepted: 04/14/2011] [Indexed: 01/08/2023] Open
Abstract
Background Mycobacterium tuberculosis (Mtb) heparin binding hemagglutinin (HBHA) is an Ag known to evoke effective host immune responses during tuberculosis infection. However, the molecular basis of the host immune response to HBHA has not been fully characterized. In this study, we examined the molecular mechanisms by which HBHA can induce the expression of proinflammatory cytokines in macrophages. Methods HBHA-induced mRNA and protein levels of proinflammatory cytokines were determined in bone marrow-derived macrophages (BMDMs) using RT-PCR and ELISA analysis. The roles of intracellular signaling pathways for NF-κB, PI3-K/Akt, and MAPKs were investigated in macrophage proinflammatory responses after stimulation with HBHA. Results HBHA robustly activated the expression of mRNA and protein of both TNF-α and IL-6, and induced phosphorylation of NF-κB, Akt, and MAPKs in BMDMs. Both TNF-α and IL-6 production by HBHA was regulated by the NF-κB, PI3-K, and MAPK pathways. Furthermore, PI3-K activity was required for the HBHA-induced activation of ERK1/2 and p38 MAPK, but not JNK, pathways. Conclusion These data suggest that mycobacterial HBHA significantly induces proinflammatory responses through crosstalk between the PI3-K and MAPK pathways in macrophages.
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Affiliation(s)
- Ki-Hye Kim
- Department of Microbiology, College of Medicine, Chungnam National University, Daejeon 301-747, Korea
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