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Yu W, Fan L, Wang M, Cao B, Hu X. Pterostilbene Improves Insulin Resistance Caused by Advanced Glycation End Products (AGEs) in Hepatocytes and Mice. Mol Nutr Food Res 2021; 65:e2100321. [PMID: 34085383 DOI: 10.1002/mnfr.202100321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 04/04/2021] [Revised: 05/15/2021] [Indexed: 11/07/2022]
Abstract
SCOPE Increased consumption of modern processed foods rich in AGEs is drawing worldwide concerns because they are related with rising diabetes prevalence. This study aimed to investigate if pterostilbene (PTE) regulates glucose metabolism and insulin signaling, as well as its potential mechanism in the context of AGEs exposure. METHODS AND RESULTS In vitro, Lo2 and HepG2 cells are treated with vehicle, AGEs with or without PTE. AGEs exposure directly impair insulin action as evidenced by assays of insulin-stimulated glucose uptake, consumption, and output. However, PTE efficiently rescue the AGE-induced phenotypes in both cell lines, and enhance IRS-1/PI3K/AKT insulin signaling in a dose-dependent manner. In vivo, C57BL6 mice are fed with regular, high AGEs diet and high AGEs plus PTE. PTE administration effectively improves hyperglycemia, glucose tolerance, and impaired hepatic insulin signaling induced by AGEs, consistent with the in vitro experiments. Moreover, PTE reduce AGEs accumulation in liver and serum. RNA-seq data indicate that PTE counteracts several AGEs-induced dysfunctions including diabetes related process, glucose metabolic process, immune response, and so on. CONCLUSION PTE treatment prominently reduced AGEs accumulation and alleviated AGEs-associated diabetes symptoms. PTE could be used as a promising glucose-sensitizing agent for nutritional intervention.
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Affiliation(s)
- Wenzhe Yu
- School of Medicine, Xiamen University, Xiamen, 361102, P. R. China
| | - Lida Fan
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Heath, Xiamen University, Xiamen, 361102, P. R. China
| | - Mingfu Wang
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, P. R. China
| | - Bin Cao
- School of Medicine, Xiamen University, Xiamen, 361102, P. R. China
| | - Xiaoqian Hu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Heath, Xiamen University, Xiamen, 361102, P. R. China
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2
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Xiao Q, Teng Y, Xu C, Pan W, Yang H, Zhao J, Zhou Q. Role of PI3K/AKT Signaling Pathway in Nucleus Pulposus Cells. Biomed Res Int 2021; 2021:9941253. [PMID: 34307680 PMCID: PMC8270693 DOI: 10.1155/2021/9941253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/15/2021] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate the role of PI3K/AKT signaling pathway in nucleus pulposus (NP) cells. METHODS Nucleus pulposus (NP) cells were isolated from SD rat, and thereafter, passage three (P3) NP cells were divided into the following experimental groups: control, PI3K/AKT agonist IGF-1 (25 ng/ml, 50 ng/ml, and 100 ng/ml), and PI3K/AKT inhibitor LY294002 (5 μM, 10 μM, and 20 μM). Flow cytometry and BrdU cell proliferation assays were performed to assess apoptosis and the proliferation rate of NP cells. Western blot analysis was performed to examine the protein expression level of Col II, Col X, Aggrecan, and MMP13. RESULTS PI3K/AKT inhibitor LY294002 increased the rate of apoptosis in NP cells when compared to the control and decreased the proliferation rate when compared to control. Moreover, LY294002 decreased the protein expression level of Col-II and Aggrecan in NP cells. At the same time, LY294002 increased the protein expression level of MMP13 and Col-X in NP cells. Through activating PI3K/AKT, IGF-1 increased the proliferation rate when compared to control and decreased the rate of apoptosis when compared to control. Additionally, IGF-1 decreased the protein expression level of MMP13 and Col-X and increased Col-II and Aggrecan in NP cells. CONCLUSION The inhibition of PI3K/AKT signaling pathway accelerated the apoptosis of NP cells and facilitated the extracellular matrix degradation. However, the activation of PI3K/AKT pathway partly prevented the NP cell from apoptosis and promoted their proliferation. Meanwhile, its activation also delayed the loss of extracellular matrix.
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Affiliation(s)
- Quan Xiao
- Department of Orthopaedic Surgery, The Affiliated Lianshui People's Hospital of Kangda College of Nanjing Medical Universty, Lianshui, Jiangsu, China
| | - Yun Teng
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Changming Xu
- Department of Orthopaedic Surgery, The Affiliated Lianshui People's Hospital of Kangda College of Nanjing Medical Universty, Lianshui, Jiangsu, China
| | - Wei Pan
- Department of Orthopaedic Surgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu 223002, China
| | - Hanshi Yang
- Department of Orthopaedic Surgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu 223002, China
| | - Jiali Zhao
- Department of Orthopaedic Surgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu 223002, China
| | - Quan Zhou
- Department of Orthopaedic Surgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu 223002, China
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Teixeira DE, Peruchetti DB, Silva LS, Silva-Aguiar RP, Oquendo MB, Silva-Filho JL, Takiya CM, Leal-Cardoso JH, Pinheiro AAS, Caruso-Neves C. Lithium ameliorates tubule-interstitial injury through activation of the mTORC2/protein kinase B pathway. PLoS One 2019; 14:e0215871. [PMID: 31002704 PMCID: PMC6474631 DOI: 10.1371/journal.pone.0215871] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 04/09/2019] [Indexed: 12/11/2022] Open
Abstract
Tubule-interstitial injury (TII) is a critical step in the progression of renal disease. It has been proposed that changes in proximal tubule (PT) albumin endocytosis plays an important role in the development of TII. Some reports have shown protective effects of lithium on kidney injury animal models that was correlated to proteinuria. We tested the hypothesis that lithium treatment ameliorates the development of TII due to changes in albumin endocytosis. Two experimental models were used: (1) TII induced by albumin overload in an animal model; (2) LLC-PK1 cells, a PT cell line. Lithium treatment ameliorates TII induced by albumin overload measured by (1) proteinuria; (2) collagen deposition; (3) area of tubule-interstitial space, and (4) macrophage infiltration. Lithium treatment increased mTORC2 activity leading to the phosphorylation of protein kinase B (PKB) at Ser473 and its activation. This mechanism enhanced albumin endocytosis in PT cells, which decreased the proteinuria observed in TII induced by albumin overload. This effect did not involve changes in the expression of megalin, a PT albumin receptor. In addition, activation of this pathway decreased apoptosis in LLC-PK1 cells, a PT cell line, induced by higher albumin concentration, similar to that found in pathophysiologic conditions. Our results indicate that the protective role of lithium treatment on TII induced by albumin overload involves an increase in PT albumin endocytosis due to activation of the mTORC2/PKB pathway. These results open new possibilities in understanding the effects of lithium on the progression of renal disease.
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Affiliation(s)
- Douglas E. Teixeira
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Diogo B. Peruchetti
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Leandro S. Silva
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Rodrigo P. Silva-Aguiar
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Morgana B. Oquendo
- Instituto Superior de Ciências Biomédicas, Universidade Estadual do Ceará, Fortaleza, CE, Brazil
| | - João Luiz Silva-Filho
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Christina M. Takiya
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Ana Acacia S. Pinheiro
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Celso Caruso-Neves
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Instituto Nacional de Ciência e Tecnologia em Medicina Regenerativa, INCT-Regenera, Conselho Nacional de Desenvolvimento Científico e Tecnológico/MCT, Rio de Janeiro, Brazil
- * E-mail:
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Matsushima Y, Terada K, Takata J, Karube Y, Kamei C, Sugimoto Y. Effects of fluvoxamine on nerve growth factor-induced neurite outgrowth inhibition by dexamethasone in PC12 cells. Biosci Biotechnol Biochem 2019; 83:659-665. [PMID: 30543144 DOI: 10.1080/09168451.2018.1553607] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 09/29/2018] [Accepted: 11/13/2018] [Indexed: 01/10/2023]
Abstract
In the present study, we examined the effects of fluvoxamine on nerve growth factor (NGF)-induced neurite outgrowth inhibition by dexamethasone (DEX) in PC12 cells. Fluvoxamine increased NGF-induced neurite outgrowth. Compared with co-treatment with NGF and fluvoxamine, p-Akt levels were higher than the values without fluvoxamine. The phosphorylated extracellular regulated kinase 1/2 levels were slightly increased by co-treatment with NGF and fluvoxamine. Fluvoxamine concentration-dependently improved NGF-induced neurite outgrowth inhibition by DEX. Fluvoxamine also improved the decrease in the NGF-induced p-Akt level caused by DEX. Interestingly, the sigma-1 receptor antagonist NE-100 blocked the improvement effects of fluvoxamine on NGF-induced neurite outgrowth inhibition by DEX. The selective sigma-1 receptor agonist PRE-084 also improved NGF-induced neurite outgrowth inhibition by DEX, which is blocked by NE-100. These results indicate that the improvement effects of fluvoxamine on NGF-induced neurite outgrowth inhibition by DEX may be attributable to the phosphorylation of Akt and the sigma-1 receptor.
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Affiliation(s)
- Yukari Matsushima
- a Faculty of Pharmaceutical Sciences, Department of Pharmacology , Yasuda Women's University , Hiroshima , Japan
- b Faculty of Pharmaceutical Sciences, Department of Kampo and Natural Product Chemistry , Yokohama University of Pharmacy , Yokohama , Japan
| | - Kazuki Terada
- c Faculty of Pharmaceutical Sciences, Laboratory of Drug Design and Drug Delivery , Fukuoka University , Fukuoka , Japan
| | - Jiro Takata
- c Faculty of Pharmaceutical Sciences, Laboratory of Drug Design and Drug Delivery , Fukuoka University , Fukuoka , Japan
| | - Yoshiharu Karube
- c Faculty of Pharmaceutical Sciences, Laboratory of Drug Design and Drug Delivery , Fukuoka University , Fukuoka , Japan
| | - Chiaki Kamei
- a Faculty of Pharmaceutical Sciences, Department of Pharmacology , Yasuda Women's University , Hiroshima , Japan
| | - Yumi Sugimoto
- d Faculty of Pharmaceutical Sciences, Department of Pharmacology , Himeji Dokkyo University , Himeji , Japan
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Han J, Zhang L, Zhang J, Jiang Q, Tong D, Wang X, Gao X, Zhao L, Huang C. CREBRF promotes the proliferation of human gastric cancer cells via the AKT signaling pathway. Cell Mol Biol (Noisy-le-grand) 2018; 64:40-45. [PMID: 29729692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 04/03/2018] [Accepted: 04/09/2018] [Indexed: 06/08/2023]
Abstract
Gastric cancer (GC) is one of the most common malignant cancer around the world, however the mechanisms is still unclear. In the present study, we investigated the function of CREB3 regulatory factor (CREBRF) in human GC and explored its relevant molecular mechanism. We found that CREBRF was highly expressed in primary GC tissues and the expression level was associated with the clinicopathologic characteristics of GC. CREBRF silencing inhibited GC cell proliferation and induced G1/G0 to S phase cell cycle arrest through regulating Cyclin A, Cyclin D1 and CDK2 expressions. Furthermore, the results showed that knockdown of CREBRF suppressed the activation of AKT signaling pathway. We further discovered that activating of AKT rescued the effect of CREBRF silencing on cell growth and drove cell re-enter into the S phase of the cell cycle with SC79 (a AKT activator). Taken together, our study demonstrated that CREBRF might promote GC cell proliferation and induce G1-S phase transition through activating AKT signaling pathway. These findings suggest that CREBRF acts as a novel oncogene and may be a potential therapeutic target in therapy of GC.
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Affiliation(s)
- Jiming Han
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Lu Zhang
- Department of Foreign Languages, Ming De College of Northwestern Polytechnical University, Xi'an 710124, Shaanxi Province, P.R. China
| | - Jing Zhang
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Qiuyu Jiang
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Dongdong Tong
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Xiaofei Wang
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Xing Gao
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Lingyu Zhao
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
| | - Chen Huang
- Department of Cell Biology and Genetics/Key Laboratory of Environment and Genes Related to Diseases, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710049, Shaanxi Province, P.R. China
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Jovanović L, Pantelić M, Prodanović R, Vujanac I, Đurić M, Tepavčević S, Vranješ-Đurić S, Korićanac G, Kirovski D. Effect of Peroral Administration of Chromium on Insulin Signaling Pathway in Skeletal Muscle Tissue of Holstein Calves. Biol Trace Elem Res 2017; 180:223-232. [PMID: 28378114 DOI: 10.1007/s12011-017-1007-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [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: 12/26/2016] [Accepted: 03/28/2017] [Indexed: 01/06/2023]
Abstract
The objective of this study was to investigate the effects of peroral administration of chromium-enriched yeast on glucose tolerance in Holstein calves, assessed by insulin signaling pathway molecule determination and intravenous glucose tolerance test (IVGTT). Twenty-four Holstein calves, aged 1 month, were chosen for the study and divided into two groups: the PoCr group (n = 12) that perorally received 0.04 mg of Cr/kg of body mass daily, for 70 days, and the NCr group (n = 12) that received no chromium supplementation. Skeletal tissue samples from each calf were obtained on day 0 and day 70 of the experiment. Chromium supplementation increased protein content of the insulin β-subunit receptor, phosphorylation of insulin receptor substrate 1 at Tyrosine 632, phosphorylation of Akt at Serine 473, glucose transporter-4, and AMP-activated protein kinase in skeletal muscle tissue, while phosphorylation of insulin receptor substrate 1 at Serine 307 was not affected by chromium treatment. Results obtained during IVGTT, which was conducted on days 0, 30, 50, and 70, suggested an increased insulin sensitivity and, consequently, a better utilization of glucose in the PoCr group. Lower basal concentrations of glucose and insulin in the PoCr group on days 30 and 70 were also obtained. Our results indicate that chromium supplementation improves glucose utilization in calves by enhancing insulin intracellular signaling in the skeletal muscle tissue.
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Affiliation(s)
- Ljubomir Jovanović
- Department for Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Marija Pantelić
- Laboratory for Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Radiša Prodanović
- Department for Ruminants and Swine Diseases, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivan Vujanac
- Department for Ruminants and Swine Diseases, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Miloje Đurić
- Department for Reproduction, Fertility and Artificial Insemination, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Snežana Tepavčević
- Laboratory for Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Sanja Vranješ-Đurić
- Laboratory for Radioisotopes, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Goran Korićanac
- Laboratory for Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Danijela Kirovski
- Department for Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia.
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Campello RS, Fátima LA, Barreto-Andrade JN, Lucas TF, Mori RC, Porto CS, Machado UF. Estradiol-induced regulation of GLUT4 in 3T3-L1 cells: involvement of ESR1 and AKT activation. J Mol Endocrinol 2017; 59:257-268. [PMID: 28729437 DOI: 10.1530/jme-17-0041] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 06/07/2017] [Accepted: 07/20/2017] [Indexed: 12/11/2022]
Abstract
Impaired insulin-stimulated glucose uptake involves reduced expression of the GLUT4 (solute carrier family 2 facilitated glucose transporter member 4, SLC2A4 gene). 17β-estradiol (E2) modulates SLC2A4/GLUT4 expression, but the involved mechanisms are unclear. Although E2 exerts biological effects by binding to estrogen receptors 1/2 (ESR1/2), which are nuclear transcriptional factors; extranuclear effects have also been proposed. We hypothesize that E2 regulates GLUT4 through an extranuclear ESR1 mechanism. Thus, we investigated the effects of E2 upon (1) subcellular distribution of ESRs and the proto-oncogene tyrosine-protein kinases (SRC) involvement; (2) serine/threonine-protein kinase (AKT) activation; (3) Slc2a4/GLUT4 expression and (4) GLUT4 subcellular distribution and glucose uptake in 3T3-L1 adipocytes. Differentiated 3T3-L1 adipocytes were cultivated or not with E2 for 24 h, and additionally treated or not with ESR1-selective agonist (PPT), ESR1-selective antagonist (MPP) or selective SRC inhibitor (PP2). Subcellular distribution of ESR1, ESR2 and GLUT4 was analyzed by immunocytochemistry; Slc2a4 mRNA and GLUT4 were quantified by qPCR and Western blotting, respectively; plasma membrane GLUT4 translocation and glucose uptake were analyzed under insulin stimulus for 20 min or not. E2 induced (1) translocation of ESR1, but not of ESR2, from nucleus to plasma membrane and AKT phosphorylation, effects mimicked by PPT and blocked by MPP and PP2; (2) increased Slc2a4/GLUT4 expression and (3) increased insulin-stimulated GLUT4 translocation and glucose uptake. In conclusion, E2 treatment promoted a SRC-mediated nucleus-plasma membrane shuttle of ESR1, and increased AKT phosphorylation, Slc2a4/GLUT4 expression and plasma membrane GLUT4 translocation; consequently, improving insulin-stimulated glucose uptake. These results unravel mechanisms through which estrogen improves insulin sensitivity.
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Affiliation(s)
- Raquel S Campello
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Luciana A Fátima
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - João Nilton Barreto-Andrade
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Thais F Lucas
- Section of Experimental EndocrinologyDepartment of Pharmacology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Rosana C Mori
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Catarina S Porto
- Section of Experimental EndocrinologyDepartment of Pharmacology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ubiratan F Machado
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Wang C, Han J, Li DJ, Yang Z, Zhang L. Protective effects of hydrogen sulfide on portal hypertensive vasculopathy in rabbits by activating AKT-NF-κB pathway. ACTA ACUST UNITED AC 2017; 37:348-351. [PMID: 28585141 DOI: 10.1007/s11596-017-1738-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 08/26/2016] [Revised: 05/01/2017] [Indexed: 01/30/2023]
Abstract
The role of hydrogen sulfide (H2S) in portal hypertension (PH)-induced esophagus-gastric junction vascular lesions in rabbits was observed. The rabbit PH models were established. The animals were randomly divided into the following groups: normal, PH, PH+sodium hydrosulfide (PH+S), PH+propargylglycine (PH+PPG). The plasma H2S levels, apoptosis of esophageal-gastric junction vascular smooth muscle cells, and the expression of nuclear transcription factor-κB (NF-κB), p-AKT, IκBa and Bcl-2 were detected. The cystathionine γ lyase (cystathionine-gamma-splitting enzyme, CSE) in the junction vascular tissue was measured. The results showed that the plasma H2S levels and the CSE expression levels had statistically significant difference among different groups (P<0.05). As compared with PH group, plasma H2S levels were declined obviously (11.9±4.2 vs. 20.6±4.5, P<0.05), and CSE expression levels in the junction vascular tissue were notably reduced (1.7±0.6 vs. 2.8±0.8, P<0.05), apoptosis rate of vascular smooth muscle cells per unit area was significantly decreased (0.10±0.15 vs. 0.24±0.07, P<0.05), and the expression levels of p-AKT and NF-κB were significantly decreased (2.31±0.33 vs. 3.04±0.38, P<0.05; 0.33±0.17 vs. 0.51±0.23, P<0.05), however, IκBa and Bcl-2 expression increased obviously (5.57±0.17 vs. 3.67±0.13, P<0.05; 0.79±0.29 vs. 0.44±0.36, P<0.05) in PH+PPG group. As compared with PH group, H2S levels were notably increased (32.7±7.3 vs. 20.6±4.5, P<0.05), the CSE levels in the junction vascular tissue were significantly increased (6.3±0.7 vs. 2.8±0.8, P<0.05), apoptosis rate of vascular smooth muscle cells per unit area was significantly increased (0.35±0.14 vs. 0.24±0.07, P<0.05), and the expression levels of p-AKT and NF-κB were significantly increased (4.29±0.49 vs. 3.04±0.38, P<0.05; 0.77±0.27 vs. 0.51±0.23, P<0.05), yet IκBa and Bcl-2 expression decreased significantly (3.23±0.24 vs. 3.67±0.13, P<0.05; 0.31±0.23 vs. 0.48±0.34, P<0.05) in PH+S group. It is concluded that esophagus-gastric junction vascular lesions happen under PH, and apoptosis of smooth muscle cells is declined. H2S can activate NF-κB by the p-AKT pathway, leading to the down-regulation of Bcl-2, eventually stimulating apoptosis of vascular smooth muscle cells, easing PH. H2S/CSE system may play an important role in remission of PH via the AKT-NF-κB pathway.
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MESH Headings
- Alkynes/pharmacology
- Animals
- Antihypertensive Agents/pharmacology
- Apoptosis/drug effects
- Cystathionine gamma-Lyase/genetics
- Cystathionine gamma-Lyase/metabolism
- Disease Models, Animal
- Endothelial Cells/drug effects
- Endothelial Cells/metabolism
- Endothelial Cells/parasitology
- Esophagus/blood supply
- Esophagus/drug effects
- Esophagus/pathology
- Gene Expression Regulation
- Glycine/analogs & derivatives
- Glycine/pharmacology
- Hydrogen Sulfide/pharmacology
- Hypertension, Portal/complications
- Hypertension, Portal/drug therapy
- Hypertension, Portal/genetics
- Hypertension, Portal/parasitology
- Intercellular Junctions/drug effects
- Intercellular Junctions/metabolism
- Intercellular Junctions/parasitology
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/parasitology
- NF-KappaB Inhibitor alpha/genetics
- NF-KappaB Inhibitor alpha/metabolism
- NF-kappa B/agonists
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Portal System/drug effects
- Portal System/metabolism
- Portal System/parasitology
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Rabbits
- Schistosoma japonicum/growth & development
- Schistosomiasis japonica/complications
- Schistosomiasis japonica/drug therapy
- Schistosomiasis japonica/genetics
- Schistosomiasis japonica/parasitology
- Signal Transduction
- Stomach/blood supply
- Stomach/drug effects
- Stomach/pathology
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Affiliation(s)
- Chao Wang
- Department of Integrative Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Juan Han
- Department of Biliary and Pancreatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Dong-Jian Li
- Department of Integrative Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Zhen Yang
- Department of Integrative Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lin Zhang
- Department of Breast and Thyroid Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Pan C, Wang Y, Qiu MK, Wang SQ, Liu YB, Quan ZW, Ou JM. Knockdown of HMGB1 inhibits cell proliferation and induces apoptosis in hemangioma via downregulation of AKT pathway. J BIOL REG HOMEOS AG 2017; 31:41-49. [PMID: 28337869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The high mobility group box 1 (HMGB1) as a conserved non-histone nuclear protein has been involved in a variety of biological processes of cancer, such as cell proliferation, apoptosis, angiogenesis and metastasis. Despite the increased expression of HMGB1 in many malignant tumors, the functions and molecular mechanisms by which HMGB1 contributes to the formation of hemangioma (HA) remain unclear. In the present study, immunohistochemistry was used to detect the expression levels of HMGB1 in different phases of human HAs. Cell function experiments, including MTT, cell colony formation and flow cytometry analysis were performed to evaluate the effects of HMGB1 knockdown on cell proliferation and apoptosis in HA CRL-2586 EOMA cells. As a consequence, we found that HMGB1 expression was significantly increased in proliferating phase HAs compared with the involuting phase HAs and normal skin tissues (P less than 0.01). Moreover, knockdown of HMGB1 gene in vitro suppressed EOMA cell proliferation and colony formation and induced cell apoptosis and cycle arrest at G0/G1 phase by downregulation of PCNA, CyclinD1, p-AKT and upregulation of p53 and cleaved PARP. Taken together, our findings demonstrate that HMGB1 may be implicated in the formation of HA through upregulation of AKT pathway, and represent a potential therapeutic target for treating HA.
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Affiliation(s)
- C Pan
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - Y Wang
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - M K Qiu
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - S Q Wang
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - Y B Liu
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - Z W Quan
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
| | - J M Ou
- Department of General Surgery, Xinhua Hospital, Shanghai JiaoTong University, School of Medicine, Shanghai, China
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10
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Yang L, Zhang Y, Zhu M, Zhang Q, Wang X, Wang Y, Zhang J, Li J, Yang L, Liu J, Liu F, Yang Y, Kang L, Shen Y, Qi Z. Resveratrol attenuates myocardial ischemia/reperfusion injury through up-regulation of vascular endothelial growth factor B. Free Radic Biol Med 2016; 101:1-9. [PMID: 27667182 DOI: 10.1016/j.freeradbiomed.2016.09.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [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: 04/12/2016] [Revised: 08/07/2016] [Accepted: 09/20/2016] [Indexed: 12/11/2022]
Abstract
The objective was to examine the protective effect of resveratrol (RSV) on myocardial ischemia/reperfusion (IR) injury and whether the mechanism was related to vascular endothelial growth factor B (VEGF-B) signaling pathway. Rat hearts were isolated for Langendorff perfusion test and H9c2 cells were used for in vitro assessments. RSV treatment significantly improved left ventricular function, inhibited CK-MB release, and reduced infarct size in comparison with IR group ex vivo. RSV treatment markedly decreased cell death and apoptosis of H9c2 cells during IR. We found that RSV was responsible for the up-regulation of VEGF-B mRNA and protein level, which caused the activation of Akt and the inhibition of GSK3β. Additionally, RSV prevented the generation of reactive oxygen species (ROS) by up-regulating the expression of MnSOD either in vitro or ex vivo. We also found that the inhibition of VEGF-B abolished the cardioprotective effect of RSV, increased apoptosis, and led to the down-regulation of phosphorylated Akt, GSK3β, and MnSOD in H9c2 cells. These results demonstrated that RSV was able to attenuate myocardial IR injury via promotion of VEGF-B/antioxidant signaling pathway. Therefore, the up-regulation of VEGF-B can be a promising modality for clinical myocardial IR injury therapy.
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MESH Headings
- Animals
- Antioxidants/pharmacology
- Apoptosis/drug effects
- Cardiotonic Agents/pharmacology
- Cell Line
- Creatine Kinase, MB Form/antagonists & inhibitors
- Creatine Kinase, MB Form/metabolism
- Gene Expression Regulation
- Glycogen Synthase Kinase 3 beta/antagonists & inhibitors
- Glycogen Synthase Kinase 3 beta/genetics
- Glycogen Synthase Kinase 3 beta/metabolism
- Male
- Myocardial Infarction/drug therapy
- Myocardial Infarction/genetics
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardial Reperfusion Injury/drug therapy
- Myocardial Reperfusion Injury/genetics
- Myocardial Reperfusion Injury/metabolism
- Myocardial Reperfusion Injury/pathology
- Myocardium/metabolism
- Myocardium/pathology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Organ Culture Techniques
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Rats
- Rats, Sprague-Dawley
- Reactive Oxygen Species/antagonists & inhibitors
- Reactive Oxygen Species/metabolism
- Resveratrol
- Signal Transduction
- Stilbenes/pharmacology
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Vascular Endothelial Growth Factor B/agonists
- Vascular Endothelial Growth Factor B/antagonists & inhibitors
- Vascular Endothelial Growth Factor B/genetics
- Vascular Endothelial Growth Factor B/metabolism
- Ventricular Function, Left/drug effects
- Ventricular Function, Left/physiology
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Affiliation(s)
- Lei Yang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China; Tianjin Institute of Acute Abdominal Diseases of Integrated Traditional Chinese and Western Medicine, Tianjin Nankai Hospital, Tianjin 300100, China
| | - Yan Zhang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Mengmeng Zhu
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Qiong Zhang
- Department of Microbiology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, China
| | - Xiaoling Wang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Yanjiao Wang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Jincai Zhang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Jing Li
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Liang Yang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Jie Liu
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Fei Liu
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Yinan Yang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Licheng Kang
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China
| | - Yanna Shen
- Department of Microbiology, School of Laboratory Medicine, Tianjin Medical University, Tianjin 300203, China.
| | - Zhi Qi
- Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin 300071, China.
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11
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Khamoui AV, Park BS, Kim DH, Yeh MC, Oh SL, Elam ML, Jo E, Arjmandi BH, Salazar G, Grant SC, Contreras RJ, Lee WJ, Kim JS. Aerobic and resistance training dependent skeletal muscle plasticity in the colon-26 murine model of cancer cachexia. Metabolism 2016; 65:685-698. [PMID: 27085776 DOI: 10.1016/j.metabol.2016.01.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [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: 07/28/2015] [Revised: 01/14/2016] [Accepted: 01/29/2016] [Indexed: 12/20/2022]
Abstract
PURPOSE The appropriate mode of exercise training for cancer cachexia is not well-established. Using the colon-26 (C26) mouse model of cancer cachexia, we defined and compared the skeletal muscle responses to aerobic and resistance training. METHODS Twelve-month old Balb/c mice were initially assigned to control, aerobic training (AT; wheel running), or resistance training (RT; ladder climbing) (n=16-17/group). After 8weeks of training, half of each group was injected with C26 tumor cells, followed by 3 additional weeks of training. Body composition and neuromuscular function was evaluated pre- and post-training. Muscles were collected post-training and analyzed for fiber cross-sectional area (CSA), Akt-mTOR signaling, and expression of insulin-like growth factor-I (IGF-I) and myogenic regulatory factors. RESULTS Total body mass decreased (p<0.05) in C26 (-8%), AT+C26 (-18%), and RT+C26 (-15%) but not control. Sensorimotor function declined (p<0.05) in control (-16%), C26 (-13%), and RT+C26 (-23%) but not AT+C26. Similarly, strength/body weight decreased (p<0.05) in control (-7%), C26 (-21%), and RT+C26 (-10%) but not AT+C26. Gastrocnemius mass/body weight tended to be greater in AT+C26 vs. C26 (+6%, p=0.09). Enlargement of the spleen was partially corrected in AT+C26 (-27% vs. C26, p<0.05). Fiber CSA was lower in all C26 groups vs. control (-32% to 46%, p<0.05); however, the effect size calculated from C26 and AT+C26 was large (+24%, d=1.04). Phosphorylated levels of mTOR in AT+C26 exceeded C26 (+32%, p<0.05). RT+C26 showed greater mRNA expression (p<0.05) of IGF-IEa (+79%) and myogenin (+126%) with a strong tendency for greater IGF-IEb (+127%, p=0.069) vs. CONCLUSIONS Aerobic or resistance training was unable to prevent tumor-induced body weight loss. However, aerobic training may have preserved function, reduced the inflammatory response of the spleen, and marginally rescued muscle mass possibly through activation of mTOR. Aerobic training may therefore have therapeutic value for patients with cancer cachexia. In contrast, resistance training induced the expression of genes associated with muscle damage and repair. This gene response may be supportive of excessive stress generated by high resistance loading in a tumor-bearing state.
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Affiliation(s)
- Andy V Khamoui
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA
| | - Bong-Sup Park
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA
| | - Do-Houn Kim
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA
| | - Ming-Chia Yeh
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA
| | - Seung-Lyul Oh
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA
| | - Marcus L Elam
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA
| | - Edward Jo
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA; Department of Kinesiology and Health Promotion, California State Polytechnic University, Pomona, CA, USA
| | - Bahram H Arjmandi
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA
| | - Gloria Salazar
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA
| | - Samuel C Grant
- The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA; Department of Chemical and Biomedical Engineering and The National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA
| | - Robert J Contreras
- Department of Psychology and Program in Neuroscience, Florida State University, Tallahassee, FL, USA
| | - Won Jun Lee
- Department of Exercise Science, Ewha Womans University, Seoul, Republic of Korea
| | - Jeong-Su Kim
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA; The Center for Advancing Exercise and Nutrition Research on Aging, Florida State University, Tallahassee, FL, USA.
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12
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Hu M, Wang C, Li W, Lu W, Bai Z, Qin D, Yan Q, Zhu J, Krueger BJ, Renne R, Gao SJ, Lu C. A KSHV microRNA Directly Targets G Protein-Coupled Receptor Kinase 2 to Promote the Migration and Invasion of Endothelial Cells by Inducing CXCR2 and Activating AKT Signaling. PLoS Pathog 2015; 11:e1005171. [PMID: 26402907 PMCID: PMC4581863 DOI: 10.1371/journal.ppat.1005171] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Accepted: 08/27/2015] [Indexed: 02/06/2023] Open
Abstract
Kaposi's sarcoma (KS) is a highly disseminated angiogenic tumor of endothelial cells linked to infection by Kaposi's sarcoma-associated herpesvirus (KSHV). KSHV encodes more than two dozens of miRNAs but their roles in KSHV-induced tumor dissemination and metastasis remain unknown. Here, we found that ectopic expression of miR-K12-3 (miR-K3) promoted endothelial cell migration and invasion. Bioinformatics and luciferase reporter analyses showed that miR-K3 directly targeted G protein-coupled receptor (GPCR) kinase 2 (GRK2, official gene symbol ADRBK1). Importantly, overexpression of GRK2 reversed miR-K3 induction of cell migration and invasion. Furthermore, the chemokine receptor CXCR2, which was negatively regulated by GRK2, was upregulated in miR-K3-transduced endothelial cells. Knock down of CXCR2 abolished miR-K3-induced cell migration and invasion. Moreover, miR-K3 downregulation of GRK2 relieved its direct inhibitory effect on AKT. Both CXCR2 induction and the release of AKT from GRK2 were required for miR-K3 maximum activation of AKT and induction of cell migration and invasion. Finally, deletion of miR-K3 from the KSHV genome abrogated its effect on the GRK2/CXCR2/AKT pathway and KSHV-induced migration and invasion. Our data provide the first-line evidence that, by repressing GRK2, miR-K3 facilitates cell migration and invasion via activation of CXCR2/AKT signaling, which likely contribute to the dissemination of KSHV-induced tumors. Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS). KS is a highly disseminated tumor often involved with visceral organs. Experimentally, KSHV infection induces the invasiveness of endothelial cells. KSHV encodes twelve precursor miRNAs (pre-miRNAs), which are processed into at least 25 mature miRNAs. However, the roles of these miRNAs in KSHV-induced tumor dissemination remain unknown. Here, we investigated KSHV-encoded miR-K12-3 (miR-K3) promotion of endothelial cell migration and invasion, which are the underlying mechanisms of tumor dissemination. We demonstrated that miR-K3 promoted cell migration and invasion by directly targeting G protein-coupled receptor (GPCR) kinase 2 (GRK2). Furthermore, we found that the chemokine receptor CXCR2, which was negatively regulated by GRK2, and its downstream AKT signaling positively mediated miR-K3-induced cell migration and invasion. miR-K3 downregulation of GRK2 relieved its direct inhibitory effect on AKT, and both CXCR2 induction and the release of AKT from GRK2 were required for miR-K3 maximum activation of AKT and induction of cell migration and invasion. These results show that miR-K3 and its the downstream pathway may be potential therapeutic targets for the treatment of KSHV-associated malignancies.
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MESH Headings
- Cell Movement
- Cells, Cultured
- Endothelium, Vascular/immunology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Endothelium, Vascular/virology
- Enzyme Repression
- G-Protein-Coupled Receptor Kinase 2/antagonists & inhibitors
- G-Protein-Coupled Receptor Kinase 2/genetics
- G-Protein-Coupled Receptor Kinase 2/metabolism
- Gene Deletion
- Herpesvirus 8, Human/immunology
- Herpesvirus 8, Human/physiology
- Host-Pathogen Interactions
- Human Umbilical Vein Endothelial Cells/immunology
- Human Umbilical Vein Endothelial Cells/metabolism
- Human Umbilical Vein Endothelial Cells/pathology
- Human Umbilical Vein Endothelial Cells/virology
- Humans
- MicroRNAs/metabolism
- Mutation
- Neoplasm Invasiveness
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- RNA/metabolism
- RNA Interference
- RNA, Viral/metabolism
- Receptors, Interleukin-8B/agonists
- Receptors, Interleukin-8B/genetics
- Receptors, Interleukin-8B/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Sarcoma, Kaposi/immunology
- Sarcoma, Kaposi/metabolism
- Sarcoma, Kaposi/pathology
- Sarcoma, Kaposi/virology
- Signal Transduction
- Virus Internalization
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Affiliation(s)
- Minmin Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, P. R. China
- Key Laboratory Of Pathogen Biology Of Jiangsu Province, Nanjing Medical University, Nanjing, P. R. China
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
| | - Cong Wang
- Department of Pathology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, P. R. China
| | - Wan Li
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
| | - Weiping Lu
- Department of Endocrinology and Metabolism, Huai’an First People’s Hospital, Nanjing Medical University, 6 Beijing Road West, Huai’an, Jiangsu, P. R. China
| | - Zhiqiang Bai
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
| | - Di Qin
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
| | - Qin Yan
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
- * E-mail: (QY); (CL)
| | - Jianzhong Zhu
- Cancer Virology Program, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania, United States of America
| | - Brian J. Krueger
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, United States of America
| | - Rolf Renne
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, Florida, United States of America
| | - Shou-Jiang Gao
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Chun Lu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, P. R. China
- Key Laboratory Of Pathogen Biology Of Jiangsu Province, Nanjing Medical University, Nanjing, P. R. China
- Department of Microbiology, Nanjing Medical University, Nanjing, P. R. China
- * E-mail: (QY); (CL)
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Nayeb-Hashemi H, Desai A, Demchev V, Bronson RT, Hornick JL, Cohen DE, Ukomadu C. Targeted disruption of fibrinogen like protein-1 accelerates hepatocellular carcinoma development. Biochem Biophys Res Commun 2015. [PMID: 26225745 DOI: 10.1016/j.bbrc.2015.07.078] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fibrinogen like protein-1 (Fgl1) is a predominantly liver expressed protein that has been implicated as both a hepatoprotectant and a hepatocyte mitogen. Fgl1 expression is decreased in hepatocellular carcinoma (HCC) and its loss correlates with a poorly differentiated phenotype. To better elucidate the role of Fgl1 in hepatocarcinogenesis, we treated mice wild type or null for Fgl1 with diethyl nitrosamine and monitored for incidence of hepatocellular cancer. We find that mice lacking Fgl1 develop HCC at more than twice the rate of wild type mice. We show that hepatocellular cancers from Fgl1 null mice are molecularly distinct from those of the wild type mice. In tumors from Fgl1 null mice there is enhanced activation of Akt and downstream targets of the mammalian target of rapamycin (mTOR). In addition, there is paradoxical up regulation of putative hepatocellular cancer tumor suppressors; tripartite motif-containing protein 35 (Trim35) and tumor necrosis factor super family 10b (Tnfrsf10b). Taken together, these findings suggest that Fgl1 acts as a tumor suppressor in hepatocellular cancer through an Akt dependent mechanism and supports its role as a potential therapeutic target in HCC.
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Affiliation(s)
- Hamed Nayeb-Hashemi
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine. Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Anal Desai
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine. Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Valeriy Demchev
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine. Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Roderick T Bronson
- Department of Microbiology and Immunology, Harvard Medical School, Boston, MA 02115, USA
| | - Jason L Hornick
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - David E Cohen
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine. Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Chinweike Ukomadu
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine. Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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14
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Capel F, Acquaviva C, Pitois E, Laillet B, Rigaudière JP, Jouve C, Pouyet C, Gladine C, Comte B, Vianey Saban C, Morio B. DHA at nutritional doses restores insulin sensitivity in skeletal muscle by preventing lipotoxicity and inflammation. J Nutr Biochem 2015; 26:949-59. [PMID: 26007287 DOI: 10.1016/j.jnutbio.2015.04.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [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: 10/23/2014] [Revised: 02/05/2015] [Accepted: 04/02/2015] [Indexed: 12/20/2022]
Abstract
Skeletal muscle plays a major role in the control of whole body glucose disposal in response to insulin stimulus. Excessive supply of fatty acids to this tissue triggers cellular and molecular disturbances leading to lipotoxicity, inflammation, mitochondrial dysfunctions, impaired insulin response and decreased glucose uptake. This study was conducted to analyze the preventive effect of docosahexaenoic acid (DHA), a long-chain polyunsaturated n-3 fatty acid, against insulin resistance, lipotoxicity and inflammation in skeletal muscle at doses compatible with nutritional supplementation. DHA (30 μM) prevented insulin resistance in C2C12 myotubes exposed to palmitate (500 μM) by decreasing protein kinase C (PKC)-θ activation and restoring cellular acylcarnitine profile, insulin-dependent AKT phosphorylation and glucose uptake. Furthermore, DHA protected C2C12 myotubes from palmitate- or lipopolysaccharide-induced increase in Ptgs2, interleukin 6 and tumor necrosis factor-α mRNA level, probably through the inhibition of p38 MAP kinase and c-Jun amino-terminal kinase. In LDLR -/- mice fed a high-cholesterol-high-sucrose diet, supplementation with DHA reaching up to 2% of daily energy intake enhanced the insulin-dependent AKT phosphorylation and reduced the PKC-θ activation in skeletal muscle. Therefore, DHA used at physiological doses participates in the regulation of muscle lipid and glucose metabolisms by preventing lipotoxicity and inflammation.
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MESH Headings
- Absorption, Physiological
- Animals
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/immunology
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/prevention & control
- Diet, Western/adverse effects
- Dietary Supplements
- Docosahexaenoic Acids/administration & dosage
- Docosahexaenoic Acids/metabolism
- Docosahexaenoic Acids/therapeutic use
- Fish Oils/administration & dosage
- Fish Oils/therapeutic use
- Glucose/metabolism
- Hindlimb
- Insulin Resistance
- Isoenzymes/antagonists & inhibitors
- Isoenzymes/metabolism
- Lipid Metabolism
- Mice
- Mice, Knockout
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/immunology
- Muscle, Skeletal/metabolism
- Myositis/blood
- Myositis/immunology
- Myositis/metabolism
- Myositis/prevention & control
- Phosphorylation
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/metabolism
- Protein Kinase C-theta
- Protein Processing, Post-Translational
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/metabolism
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Tuna
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Affiliation(s)
- Frédéric Capel
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| | - Cécile Acquaviva
- Service Maladies Héréditaires du Métabolisme, Centre de Biologie et Pathologie Est, CHU de Lyon, France
| | - Elodie Pitois
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Brigitte Laillet
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Jean-Paul Rigaudière
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Chrystèle Jouve
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Corinne Pouyet
- INRA, UMR 1019, Plateforme d'Exploration du Métabolisme, UNH, F-63000 Clermont-Ferrand, France
| | - Cècile Gladine
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Blandine Comte
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
| | - Christine Vianey Saban
- Service Maladies Héréditaires du Métabolisme, Centre de Biologie et Pathologie Est, CHU de Lyon, France
| | - Bèatrice Morio
- UMR 1019, Unité de Nutrition Humaine, INRA, Centre de Recherche en Nutrition Humaine (CRNH) Auvergne, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France
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15
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Liu T, Fang Y, Liu S, Yu X, Zhang H, Liang M, Ding X. Limb ischemic preconditioning protects against contrast-induced acute kidney injury in rats via phosphorylation of GSK-3β. Free Radic Biol Med 2015; 81:170-82. [PMID: 25451640 DOI: 10.1016/j.freeradbiomed.2014.10.509] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [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: 05/28/2014] [Revised: 10/16/2014] [Accepted: 10/17/2014] [Indexed: 12/31/2022]
Abstract
Contrast-induced acute kidney injury (CI-AKI) resulting from the use of intravascular iodinated contrast media for diagnostic and interventional cardiovascular procedures is associated with substantial morbidity and mortality. Despite preventative measures intended to mitigate the risk of CI-AKI, there remains a need for a novel and effective therapeutic approach. Limb ischemic preconditioning (LIPC), where short-term ischemia/reperfusion is applied to an arm prior to administration of the contrast agent, has been shown in several trials to preserve renal function in patients at high risk for CI-AKI. However, the underlying mechanism by which this procedure provides renoprotection against contrast media insults is not known. Here, we explored the molecular mechanism(s) of LIPC-induced protection of the kidneys from CI-AKI, particularly the role of phosphorylated glycogen synthase kinase-3β (GSK-3β). We used a novel CI-AKI model consisting of 5/6 nephrectomized (NE) rats at 6 weeks after the ablative surgery. LIPC- or sham-treated rats were administered iohexol (10 ml/kg, 3.5 gI) via the tail vein. The results showed that LIPC protected the kidneys against iohexol-induced injury. This protective effect was accompanied by the attenuation of renal dysfunction, tubular damage, apoptosis, mitochondrial swelling, oxidative stress, and inflammation. Furthermore, LIPC-induced renoprotection was blocked via treatment with inhibitors of PI3K (wortmannin or LY294002), but not ERK (U0126 or PD98059). LIPC also increased the protein expression levels of phospho-Akt, phospho-GSK-3β, and nuclear Nrf2, and decreased the levels of nuclear NF-κB. A specific GSK-3β inhibitor (SB216763) mimicked this effect of LIPC, by inhibiting the opening of the mitochondrial permeability transition pore and reducing the levels of oxidative stress and inflammation via activation of Nrf2 and suppression of NF-κB. The above results demonstrate that LIPC induces protection against CI-AKI, making this procedure a promising strategy for preventing CI-AKI. In particular, this renoprotective effect involves the phosphorylation of GSK-3β.
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Affiliation(s)
- Tongqiang Liu
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Division of Nephrology, the Affiliated Changzhou No. 2 Hospital of Nanjing Medical College, Changzhou 213003, Jiangsu, China
| | - Yi Fang
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Institute of Kidney and Dialysis, Shanghai 200032, China
| | - Shaopeng Liu
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xiaofang Yu
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Institute of Kidney and Dialysis, Shanghai 200032, China
| | - Hui Zhang
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Mingyu Liang
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53201, USA
| | - Xiaoqiang Ding
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Institute of Kidney and Dialysis, Shanghai 200032, China.
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16
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Cheng Y, Kim J, Li XX, Hsueh AJ. Promotion of ovarian follicle growth following mTOR activation: synergistic effects of AKT stimulators. PLoS One 2015; 10:e0117769. [PMID: 25710488 PMCID: PMC4340052 DOI: 10.1371/journal.pone.0117769] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 01/02/2015] [Indexed: 01/22/2023] Open
Abstract
Mammalian target of rapamycin (mTOR) is a serine/threonine kinase and mTOR signaling is important in regulating cell growth and proliferation. Recent studies using oocyte- and granulosa cell-specific deletion of mTOR inhibitor genes TSC1 or TSC2 demonstrated the important role of mTOR signaling in the promotion of ovarian follicle development. We now report that treatment of ovaries from juvenile mice with an mTOR activator MHY1485 stimulated mTOR, S6K1 and rpS6 phosphorylation. Culturing ovaries for 4 days with MHY1485 increased ovarian explant weights and follicle development. In vivo studies further demonstrated that pre-incubation of these ovaries with MHY1485 for 2 days, followed by allo-grafting into kidney capsules of adult ovariectomized hosts for 5 days, led to marked increases in graft weights and promotion of follicle development. Mature oocytes derived from MHY1485-activated ovarian grafts could be successfully fertilized, leading the delivery of healthy pups. We further treated ovaries with the mTOR activator together with AKT activators (PTEN inhibitor and phosphoinositol-3-kinase stimulator) before grafting and found additive enhancement of follicle growth. Our studies demonstrate the ability of an mTOR activator in promoting follicle growth, leading to a potential strategy to stimulate preantral follicle growth in infertile patients.
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Affiliation(s)
- Yuan Cheng
- Program of Reproductive and Stem Cell Biology, Department of Ob/Gyn, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Jaehong Kim
- Program of Reproductive and Stem Cell Biology, Department of Ob/Gyn, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Xiao Xiao Li
- Program of Reproductive and Stem Cell Biology, Department of Ob/Gyn, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Aaron J. Hsueh
- Program of Reproductive and Stem Cell Biology, Department of Ob/Gyn, Stanford University School of Medicine, Stanford, CA, United States of America
- * E-mail:
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17
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Zhang CZ, Wang XD, Wang HW, Cai Y, Chao LQ. Sorafenib inhibits liver cancer growth by decreasing mTOR, AKT, and PI3K expression. J BUON 2015; 20:218-222. [PMID: 25778319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE The purpose of this study was to determine the impact of sorafenib on PI3K/AKT/mTOR signaling pathway and to further define its mechanism for treating hepatocellular carcinoma (HCC). METHODS Human SMMC-7721 hepatic carcinoma cells were treated with or without 4 μmoL/L sorafenib. SMMC- 7721 cells were harvested at various time points (0-48 hrs) and assessed for changes in PI3K, mTOR, and AKT protein and mRNA levels. RESULTS Human SMMC-7721 hepatic tumor cells exposed to sorafenib had decreased expression of PI3K/mTOR/AKT. CONCLUSION Sorafenib appears to inhibit hepatic tumor growth by downregulating PI3k/Akt/mTOR signaling pathway.
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Affiliation(s)
- Chi-zhi Zhang
- 1Institute of Hepatology, Affiliated Hospital of Hubei University of Chinese Medicine, Wuhan, Hubei, China
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18
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Xu ZP, Li L, Bao J, Wang ZH, Zeng J, Liu EJ, Li XG, Huang RX, Gao D, Li MZ, Zhang Y, Liu GP, Wang JZ. Magnesium protects cognitive functions and synaptic plasticity in streptozotocin-induced sporadic Alzheimer's model. PLoS One 2014; 9:e108645. [PMID: 25268773 PMCID: PMC4182554 DOI: 10.1371/journal.pone.0108645] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/25/2014] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by profound synapse loss and impairments of learning and memory. Magnesium affects many biochemical mechanisms that are vital for neuronal properties and synaptic plasticity. Recent studies have demonstrated that the serum and brain magnesium levels are decreased in AD patients; however, the exact role of magnesium in AD pathogenesis remains unclear. Here, we found that the intraperitoneal administration of magnesium sulfate increased the brain magnesium levels and protected learning and memory capacities in streptozotocin-induced sporadic AD model rats. We also found that magnesium sulfate reversed impairments in long-term potentiation (LTP), dendritic abnormalities, and the impaired recruitment of synaptic proteins. Magnesium sulfate treatment also decreased tau hyperphosphorylation by increasing the inhibitory phosphorylation of GSK-3β at serine 9, thereby increasing the activity of Akt at Ser473 and PI3K at Tyr458/199, and improving insulin sensitivity. We conclude that magnesium treatment protects cognitive function and synaptic plasticity by inhibiting GSK-3β in sporadic AD model rats, which suggests a potential role for magnesium in AD therapy.
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Affiliation(s)
- Zhi-Peng Xu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian Bao
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi-Hao Wang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Juan Zeng
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - En-Jie Liu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Guang Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Rong-Xi Huang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Di Gao
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Meng-Zhu Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yao Zhang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Li Yuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Gong-Ping Liu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian-Zhi Wang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Park JH, Shin YJ, Riew TR, Lee MY. The indolinone MAZ51 induces cell rounding and G2/M cell cycle arrest in glioma cells without the inhibition of VEGFR-3 phosphorylation: involvement of the RhoA and Akt/GSK3β signaling pathways. PLoS One 2014; 9:e109055. [PMID: 25268128 PMCID: PMC4182637 DOI: 10.1371/journal.pone.0109055] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Accepted: 09/02/2014] [Indexed: 12/20/2022] Open
Abstract
MAZ51 is an indolinone-based molecule originally synthesized as a selective inhibitor of vascular endothelial growth factor receptor (VEGFR)-3 tyrosine kinase. This study shows that exposure of two glioma cell lines, rat C6 and human U251MG, to MAZ51 caused dramatic shape changes, including the retraction of cellular protrusions and cell rounding. These changes were caused by the clustering and aggregation of actin filaments and microtubules. MAZ51 also induced G2/M phase cell cycle arrest. This led to an inhibition of cellular proliferation, without triggering significant cell death. These alterations induced by MAZ51 occurred with similar dose- and time-dependent patterns. Treatment of glioma cells with MAZ51 resulted in increased levels of phosphorylated GSK3β through the activation of Akt, as well as increased levels of active RhoA. Interestingly, MAZ51 did not affect the morphology and cell cycle patterns of rat primary cortical astrocytes, suggesting it selectively targeted transformed cells. Immunoprecipitation–western blot analyses indicated that MAZ51 did not decrease, but rather increased, tyrosine phosphorylation of VEGFR-3. To confirm this unanticipated result, several additional experiments were conducted. Enhancing VEGFR-3 phosphorylation by treatment of glioma cells with VEGF-C affected neither cytoskeleton arrangements nor cell cycle patterns. In addition, the knockdown of VEGFR-3 in glioma cells did not cause morphological or cytoskeletal alterations. Furthermore, treatment of VEGFR-3-silenced cells with MAZ51 caused the same alterations of cell shape and cytoskeletal arrangements as that observed in control cells. These data indicate that MAZ51 causes cytoskeletal alterations and G2/M cell cycle arrest in glioma cells. These effects are mediated through phosphorylation of Akt/GSK3β and activation of RhoA. The anti-proliferative activity of MAZ51 does not require the inhibition of VEGFR-3 phosphorylation, suggesting that it is a potential candidate for further clinical investigation for treatment of gliomas, although the precise mechanism(s) underlying its effects remain to be determined.
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Affiliation(s)
- Joo-Hee Park
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yoo-Jin Shin
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Tae-Ryong Riew
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Mun-Yong Lee
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
- * E-mail:
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20
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Vandanmagsar B, Haynie KR, Wicks SE, Bermudez EM, Mendoza TM, Ribnicky D, Cefalu WT, Mynatt RL. Artemisia dracunculus L. extract ameliorates insulin sensitivity by attenuating inflammatory signalling in human skeletal muscle culture. Diabetes Obes Metab 2014; 16:728-38. [PMID: 24521217 PMCID: PMC4107009 DOI: 10.1111/dom.12274] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [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: 11/08/2013] [Revised: 12/09/2013] [Accepted: 02/06/2014] [Indexed: 02/01/2023]
Abstract
AIMS Bioactives of Artemisia dracunculus L. (termed PMI 5011) have been shown to improve insulin action by increasing insulin signalling in skeletal muscle. However, it was not known if PMI 5011's effects are retained during an inflammatory condition. We examined the attenuation of insulin action and whether PMI 5011 enhances insulin signalling in the inflammatory environment with elevated cytokines. METHODS Muscle cell cultures derived from lean, overweight and diabetic-obese subjects were used. Expression of pro-inflammatory genes and inflammatory response of human myotubes were evaluated by real-time polymerase chain reaction (RT-PCR). Insulin signalling and activation of inflammatory pathways in human myotubes were evaluated by multiplex protein assays. RESULTS We found increased gene expression of monocyte chemoattractant protein 1 (MCP1) and TNFα (tumour necrosis factor alpha), and basal activity of the NFkB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathway in myotubes derived from diabetic-obese subjects as compared with myotubes derived from normal-lean subjects. In line with this, basal Akt phosphorylation (Ser473) was significantly higher, while insulin-stimulated phosphorylation of Akt (Ser473) was lower in myotubes from normal-overweight and diabetic-obese subjects compared with normal-lean subjects. PMI 5011 treatment reduced basal phosphorylation of Akt and enhanced insulin-stimulated phosphorylation of Akt in the presence of cytokines in human myotubes. PMI 5011 treatment led to an inhibition of cytokine-induced activation of inflammatory signalling pathways such as Erk1/2 and IkBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha)-NFkB and moreover, NFkB target gene expression, possibly by preventing further propagation of the inflammatory response within muscle tissue. CONCLUSIONS PMI 5011 improved insulin sensitivity in diabetic-obese myotubes to the level of normal-lean myotubes despite the presence of pro-inflammatory cytokines.
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Affiliation(s)
- Bolormaa Vandanmagsar
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Kimberly R. Haynie
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Shawna E. Wicks
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Estrellita M. Bermudez
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Tamra M. Mendoza
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - David Ribnicky
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, New Jersey
| | - William T. Cefalu
- Botanical Research Center, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Randall L. Mynatt
- Gene Nutrient Interactions Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
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21
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Hou CH, Lin FL, Tong KB, Hou SM, Liu JF. Transforming growth factor alpha promotes osteosarcoma metastasis by ICAM-1 and PI3K/Akt signaling pathway. Biochem Pharmacol 2014; 89:453-63. [PMID: 24685520 DOI: 10.1016/j.bcp.2014.03.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [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: 12/04/2013] [Revised: 03/20/2014] [Accepted: 03/20/2014] [Indexed: 12/21/2022]
Abstract
Osteosarcoma is the most common primary malignancy of bone and is characterized by a high malignant and metastatic potential. Transforming growth factor alpha (TGF-α) is classified as the EGF (epidermal growth factor)-like family, which is involved in cancer cellular activities such as proliferation, motility, migration, adhesion and invasion abilities. However, the effect of TGF-α on human osteosarcoma is largely unknown. We found that TGF-α increased the cell migration and expression of intercellular adhesion molecule-1 (ICAM-1) in human osteosarcoma cells. Transfection of cells with ICAM-1 siRNA reduced TGF-α-mediated cell migration. We also found that the phosphatidylinositol 3'-kinase (PI3K)/Akt/NF-κB pathway was activated after TGF-α treatment, and TGF-α-induced expression of ICAM-1 and cell migration was inhibited by the specific inhibitors and siRNAs of PI3K, Akt, and NF-κB cascades. In addition, knockdown of TGF-α expression markedly decreased cell metastasis in vitro and in vivo. Our results indicate that TGF-α/EGFR interaction elicits PI3K and Akt activation, which in turn activates NF-κB, resulting in the expression of ICAM-1 and contributing the migration of human osteosarcoma cells.
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Affiliation(s)
- Chun-Han Hou
- Department of Orthopedic Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Feng-Ling Lin
- Department of Dermatology, Sijhih Cathay General Hospital, Taipei, Taiwan
| | - Kai-Biao Tong
- Veterinarian Central Laboratory, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
| | - Sheng-Mon Hou
- Department of Orthopedic Surgery, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
| | - Ju-Fang Liu
- Central Laboratory, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
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22
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Kubota M, Sato Y, Khookhor O, Ekberg K, Chibalin AV, Wahren J. Enhanced insulin action following subcutaneous co-administration of insulin and C-peptide in rats. Diabetes Metab Res Rev 2014; 30:124-31. [PMID: 24027001 DOI: 10.1002/dmrr.2471] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [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: 06/14/2013] [Revised: 08/12/2013] [Accepted: 09/07/2013] [Indexed: 12/27/2022]
Abstract
BACKGROUND This study was undertaken to examine if C-peptide (C) may interact with hexameric insulin and facilitate its disaggregation into the physiologically active monomeric form. METHODS Regular insulin (I) or an insulin analogue (IA) were injected s.c. in rats together with C or its C-terminal pentapeptide (PP). I or IA and C or PP were administered either as a physical mixture or into two separate s.c. depots. Whole body glucose utilization was evaluated using the euglycemic clamp technique. Phosphorylation of Akt/PKB and GSK in liver and skeletal muscles and ⁸⁶Rb⁺ uptake by L6 cells were measured. RESULTS S.c. injection of a mixture of I and C or I and PP resulted in a 30-55% greater (P < 0.01-0.001) and 15-27% (P < 0.05-0.001) longer stimulation of whole body glucose utilization than after separate injections. Insulin-stimulated phosphorylation of Akt/PKB in liver increased 35% more after injection of I and C in mixture compared with after separate injections. Phosphorylation of GSK3 was augmented by 50% (P < 0.05) following the injection of I and C in mixture compared with separate injections. Stimulation of myotubes with premixed I and C (1 nM) elicited 20% additional increase in ouabain-sensitive ⁸⁶Rb⁺ uptake (P < 0.05) in comparison with the effect when I and C were added separately. CONCLUSIONS Subcutaneous co-administration of insulin and C results in augmented insulin bioactivity at the level of tissue glucose uptake, intracellular signalling, and enzyme activation. These effects may be attributed to augmented C mediated disaggregation of hexameric insulin into its physiologically active monomeric form.
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MESH Headings
- Animals
- C-Peptide/administration & dosage
- C-Peptide/chemistry
- C-Peptide/genetics
- C-Peptide/pharmacology
- Cell Line
- Drug Combinations
- Drug Implants
- Drug Therapy, Combination
- Enzyme Activation/drug effects
- Glycogen Synthase Kinase 3/chemistry
- Glycogen Synthase Kinase 3/metabolism
- Humans
- Hypoglycemic Agents/administration & dosage
- Hypoglycemic Agents/chemistry
- Hypoglycemic Agents/pharmacology
- Insulin Lispro/administration & dosage
- Insulin Lispro/genetics
- Insulin Lispro/pharmacology
- Insulin, Regular, Human/administration & dosage
- Insulin, Regular, Human/genetics
- Insulin, Regular, Human/pharmacology
- Liver/drug effects
- Liver/enzymology
- Liver/metabolism
- Male
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/metabolism
- Oligopeptides/administration & dosage
- Oligopeptides/chemistry
- Oligopeptides/genetics
- Oligopeptides/pharmacology
- Peptide Fragments/administration & dosage
- Peptide Fragments/chemistry
- Peptide Fragments/genetics
- Peptide Fragments/pharmacology
- Phosphorylation/drug effects
- Protein Processing, Post-Translational/drug effects
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/metabolism
- Random Allocation
- Rats
- Rats, Wistar
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/chemistry
- Recombinant Proteins/pharmacology
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Affiliation(s)
- M Kubota
- Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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23
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Yuan L, Lu CL, Wang Y, Li Y, Li XY. Ang (1-7) protects islet endothelial cells from palmitate-induced apoptosis by AKT, eNOS, p38 MAPK, and JNK pathways. J Diabetes Res 2014; 2014:391476. [PMID: 24804268 PMCID: PMC3996957 DOI: 10.1155/2014/391476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/06/2014] [Accepted: 02/06/2014] [Indexed: 11/28/2022] Open
Abstract
This study aimed to explore the effect of angiotensin (1-7) (Ang (1-7)) on palmitate-induced apoptosis in islet endothelial cells and the mechanism of action. MS-1 cells were treated with palmitate in the presence or absence of Ang (1-7). The percentage of apoptotic cells was determined by DNA fragmentation and flow cytometry. Reactive oxygen species (ROS) production was measured using a Reactive Oxygen Species Assay Kit. Expression of AKT, eNOS, C-Jun N-terminal kinase (JNK), and p38 was detected by western blotting. Compared with palmitate treated group, palmitate-induced apoptosis was decreased in MS-1 cells which were preincubated with Ang (1-7) (P < 0.05). Palmitate decreased the phosphorylation of AKT and eNOS, and Ang (1-7) increased the phosphorylation of these kinases (P < 0.05), with a concomitant reduction in MS-1 cells apoptosis. Ang (1-7) also inhibited the palmitate-induced ROS production and attenuated the apoptosis-related signaling molecule JNK and p38 activation (all P < 0.05). PI3K/AKT, eNOS, p38 MAPK, and JNK inhibitors blocked the antilipoapoptosis of Ang (1-7) (all P < 0.05). Our findings suggest that Ang (1-7) reduces palmitate-induced islet endothelial cells apoptosis. AKT/eNOS/NO signaling and JNK and p38 pathway are involved in the Ang (1-7)-mediated modulation of islet endothelial cells lipoapoptosis.
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Affiliation(s)
- Li Yuan
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- *Li Yuan:
| | - Chun-Li Lu
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Ying Wang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yang Li
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiao-Ya Li
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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Wang JQ, Chen JH, Chen YC, Chen MY, Hsieh CY, Teng SC, Wu KJ. Interaction between NBS1 and the mTOR/Rictor/SIN1 complex through specific domains. PLoS One 2013; 8:e65586. [PMID: 23762398 PMCID: PMC3675082 DOI: 10.1371/journal.pone.0065586] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 04/26/2013] [Indexed: 11/24/2022] Open
Abstract
Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome. The NBS gene product, NBS1 (p95 or nibrin), is a part of the Mre11-Rad50-NBS1 complex. SIN1 is a component of the mTOR/Rictor/SIN1 complex mediating the activation of Akt. Here we show that NBS1 interacted with mTOR, Rictor, and SIN1. The specific domains of mTOR, Rictor, or SIN1 interacted with the internal domain (a.a. 221-402) of NBS1. Sucrose density gradient showed that NBS1 was located in the same fractions as the mTOR/Rictor/SIN1 complex. Knockdown of NBS1 decreased the levels of phosphorylated Akt and its downstream targets. Ionizing radiation (IR) increased the NBS1 levels and activated Akt activity. These results demonstrate that NBS1 interacts with the mTOR/Rictor/SIN1 complex through the a.a. 221–402 domain and contributes to the activation of Akt activity.
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Affiliation(s)
- Jian-Qiu Wang
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
- Institute of Aging Research, Department of Basic Medical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Jian-Hong Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Chung Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Mei-Yu Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Ying Hsieh
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Shu-Chun Teng
- Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Kou-Juey Wu
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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25
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Li Q, Hosaka T, Harada N, Nakaya Y, Funaki M. Activation of Akt through 5-HT2A receptor ameliorates serotonin-induced degradation of insulin receptor substrate-1 in adipocytes. Mol Cell Endocrinol 2013; 365:25-35. [PMID: 22975078 DOI: 10.1016/j.mce.2012.08.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 08/27/2012] [Accepted: 08/31/2012] [Indexed: 11/26/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) was found to be elevated in the serum of diabetic patients. In this study, we investigate the mechanism of insulin desensitization caused by 5-HT. In 3T3-L1 adipocytes, 5-HT treatment induced the translocation of insulin receptor substrate-1 (IRS-1) from low density microsome (LDM), the important intracellular compartment for its functions, to cytosol, inducing IRS-1 ubiquitination and degradation. Moreover, inhibition of 5-HT-stimulated Akt activation by either ketanserin (a specific 5-HT2A receptor antagonist) or knocking-down the expression of 5-HT2A receptor promoted 5-HT-stimulated IRS-1 dissociation from 14-3-3β in LDM, leading to drastic ubiquitination. Interestingly, sarpogrelate, another antagonist of 5-HT2A receptor, protected IRS-1 from degradation through activation of Akt. This implicates the importance of Akt activation in extending IRS-1 life span through maintaining their optimal sub-location into adipocytes. Taken together, this study suggest that activation of Akt may be able to compensate the adverse effects of 5-HT by stabilizing IRS-1 in LDM.
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MESH Headings
- 14-3-3 Proteins/metabolism
- 3T3-L1 Cells
- Adipocytes, White/drug effects
- Adipocytes, White/metabolism
- Animals
- Cytosol/drug effects
- Cytosol/metabolism
- Insulin Receptor Substrate Proteins/metabolism
- Insulin Resistance
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- Microsomes/drug effects
- Microsomes/metabolism
- Protein Stability/drug effects
- Protein Transport/drug effects
- Proteolysis/drug effects
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/metabolism
- RNA Interference
- Receptor, Serotonin, 5-HT2A/chemistry
- Receptor, Serotonin, 5-HT2A/genetics
- Receptor, Serotonin, 5-HT2A/metabolism
- Serotonin/adverse effects
- Serotonin/chemistry
- Serotonin/metabolism
- Serotonin 5-HT2 Receptor Agonists/chemistry
- Serotonin 5-HT2 Receptor Agonists/metabolism
- Serotonin 5-HT2 Receptor Agonists/pharmacology
- Serotonin 5-HT2 Receptor Antagonists/pharmacology
- Ubiquitination/drug effects
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Affiliation(s)
- Qinkai Li
- Clinical Research Center for Diabetes, Tokushima University Hospital, Kuramoto-cho, Tokushima 770-8503, Japan.
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26
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Choi SS, Cha BY, Lee YS, Yonezawa T, Teruya T, Nagai K, Woo JT. Honokiol and magnolol stimulate glucose uptake by activating PI3K-dependent Akt in L6 myotubes. Biofactors 2012; 38:372-7. [PMID: 22674833 DOI: 10.1002/biof.1029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 04/27/2012] [Indexed: 01/09/2023]
Abstract
Honokiol and magnolol, ingredients of Magnolia officinalis, which is used in traditional Chinese and Japanese medicines, have been reported to have antioxidant, anticancer, and antiangiogenic effects. Effects of these compounds on glucose metabolism in adipocytes have also been reported. However, their effects on skeletal muscle glucose uptake and the underlying molecular mechanisms are still unknown. Here, we investigated the direct effects and signaling pathways activated by honokiol and magnolol in skeletal muscle cells using L6 myotubes. We found that honokiol and magnolol dose-dependently acutely stimulated glucose uptake without synergistic effects of combined administration in L6 myotubes. Treatment with honokiol and magnolol also stimulated glucose transporter-4 translocation to the cell surface. Honokiol- and magnolol-stimulated glucose uptake was blocked by the phosphatidylinositol-3 kinase inhibitor, wortmannin. Both honokiol and magnolol stimulated Akt phosphorylation, a key element in the insulin signaling pathway, which was completely inhibited by wortmannin. These results suggest that honokiol and magnolol might have beneficial effects on glucose metabolism by activating the insulin signaling pathway.
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Affiliation(s)
- Sun-Sil Choi
- Research Institute for Biological Functions, Chubu University, Kasugai, Aichi, Japan
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27
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Urban D, Thanabalasingam U, Stibenz D, Kaufmann J, Meyborg H, Fleck E, Gräfe M, Stawowy P. CD40/CD40L interaction induces E-selectin dependent leukocyte adhesion to human endothelial cells and inhibits endothelial cell migration. Biochem Biophys Res Commun 2010; 404:448-52. [PMID: 21138731 DOI: 10.1016/j.bbrc.2010.11.142] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 11/30/2010] [Indexed: 11/20/2022]
Abstract
BACKGROUND CD40 is a receptor expressed on a wide range of cells such as leukocytes and endothelial cells (EC). As a member of the tumor necrosis factor (TNF) superfamily the activation of CD40 by CD40-ligand (CD40L) plays a crucial role for the development and progression of a variety of inflammatory processes including atherosclerosis. The aim of the present study was to investigate the effect of CD40/CD40L interaction on leukocyte adhesion to the endothelium and on endothelial cell migration. METHODS AND RESULTS Human umbilical vein endothelial cells (HUVEC) were stimulated with either stable transfectants of mouse myeloma cells expressing the CD40L or wild type cells (4 h). Subsequently adhesion of leukocytes expressing Sialyl Lewis X, the counterpart for E-selectin (HL60 cells), was measured under shear stress (2-2.6 dyne/cm(2)) using a flow chamber adhesion assay. Stimulation of CD40 led to a significant increase of E-selectin dependent adhesion of leukocytes to the endothelium. Incubation of cells with either the CD40L blocking antibody TRAP-1 or the E-selectin blocking antibody BBA2 during CD40 stimulation completely abolished adhesion of leukocytes to HUVEC. Similar results were found in human cardiac microvasculature endothelial cells (HCMEC). In contrast stimulation of CD40 had no effect on adhesion of L-selectin expressing NALM6-L cells. Furthermore, CD40/CD40L interaction abrogated VEGF-induced migration of HUVEC compared to non-stimulated controls. In comparison experiments, stimulation of endothelial cells with VEGF led to a significant phosphorylation of ERK1/2, Akt, and eNOS. Stimulation of endothelial CD40 had no effect on VEGF-induced phosphorylation of ERK1/2. However, VEGF-induced activation of Akt and eNOS was reduced to baseline levels when endothelial CD40 was stimulated. CONCLUSION CD40/CD40L interaction induces E-selectin dependent adhesion of leukocytes to human endothelial cells and reduces endothelial cell migration by inhibiting the Akt/eNOS signaling pathway.
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Affiliation(s)
- Daniel Urban
- Department of Medicine/Cardiology, Deutsches Herzzentrum Berlin, Germany
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28
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Jacob MHVM, Janner DDR, Jahn MP, Kucharski LCR, Belló-Klein A, Ribeiro MFM. DHEA effects on myocardial Akt signaling modulation and oxidative stress changes in aged rats. Steroids 2009; 74:1045-50. [PMID: 19699218 DOI: 10.1016/j.steroids.2009.08.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 08/11/2009] [Accepted: 08/12/2009] [Indexed: 11/22/2022]
Abstract
The secretion of DHEA-synthesized mainly in the adrenal cortex-increases in the postnatal aging, peaks in the twenties and decreases with age afterwards. Exogenous DHEA can exert a dual effect depending on dose and on tissue. Akt is a serine/threonine kinase whose activity has been seen as an interventional approach for cardiomyopathic damage resulting from aging changes. In order to evaluate DHEA effects over myocardial Akt protein expression associated to oxidative stress markers during aging, male Wistar rats (3 and 18 months) were assigned into two groups: control or DHEA (10mg/kg, subcutaneously, for 5 weeks). In the aged group, we found increased lipid peroxidation and glutathione-S-transferase activity. DHEA produced an increase in p-Akt protein expression and a decrease in SOD activity in both ages. Akt pathway activation might be related to changes in oxidative stress parameters according to age.
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Affiliation(s)
- Maria Helena Vianna Metello Jacob
- Laboratório de Interação Neuro-Humoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Av. Sarmento Leite 500, Porto Alegre, Rio Grande do Sul, Brazil.
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29
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Abstract
Tetrahydrobiopterin (BH(4)) is an essential cofactor required for enzymatic activity of endothelial NO synthase. Recently, it has been shown that vascular protective effects of erythropoietin (EPO) are dependent on activation of endothelial NO synthase. Therefore, our objective was to characterize the effect of EPO on the biosynthesis of BH(4) in the vascular wall. Incubation of isolated C57BL/6J mouse aortas for 18 hours with recombinant human EPO (1 to 50 U/mL) caused a concentration-dependent increase in intracellular BH(4) levels and activity of GTP-cyclohydrolase I. Maximal biosynthesis of BH(4) was detected at therapeutic concentrations of 5 U/mL. Removal of the endothelium abolished EPO-induced biosynthesis of BH(4) demonstrating that the vascular endothelium is a major source of BH(4). Treatment with a selective phosphatidylinositol 3-kinase inhibitor wortmannin significantly reduced BH(4) biosynthesis stimulated by EPO. The stimulatory effect of EPO on vascular GTP-cyclohydrolase I activity, BH(4) production, and phosphorylation of endothelial NO synthase was also detected in vivo in mice treated with recombinant human EPO. These effects of EPO were abolished in protein kinase Balpha/Akt1-deficient mice. In addition, EPO significantly increased systolic blood pressure and the number of circulating platelets in Akt1-deficient mice. Our results demonstrate that EPO stimulates biosynthesis of BH(4) in vascular endothelium and that the increase in BH(4) levels is caused by de novo biosynthesis of BH(4) via the phosphatidylinositol 3-kinase/Akt1 pathway. This effect is most likely designed to provide optimal intracellular concentration of the cofactor necessary for EPO-induced elevation of endothelial NO synthase activity.
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Affiliation(s)
- Livius V d'Uscio
- Department of Anesthesiology and Molecular, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
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30
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Kahner BN, Dorsam RT, Mada SR, Kim S, Stalker TJ, Brass LF, Daniel JL, Kitamura D, Kunapuli SP. Hematopoietic lineage cell specific protein 1 (HS1) is a functionally important signaling molecule in platelet activation. Blood 2007; 110:2449-56. [PMID: 17579181 PMCID: PMC1988959 DOI: 10.1182/blood-2006-11-056069] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Collagen activates platelets through an intracellular signaling cascade downstream of glycoprotein VI (GPVI). We have investigated the contribution of hematopoietic lineage cell-specific protein 1 (HS1) downstream of GPVI in platelet activation. Stimulation of GPVI leads to tyrosine phosphorylation of HS1, which is blocked by Src-family kinase inhibitors. Coimmunoprecipitation experiments revealed that HS1 associates with Syk and phosphatidylinositol 3-kinases. HS1-null mice displayed increased bleeding times and increased time to occlusion in the FeCl(3) in vivo thrombosis model compared with their wild-type littermates. In addition, aggregation and secretion responses were diminished in HS1-null mouse platelets after stimulation of GPVI and protease-activated receptor 4 (PAR-4) agonists compared with wild-type littermate mouse platelets. Finally, Akt phosphorylation was diminished after GPVI or PAR-4 stimulation in platelets from HS1-null mice compared with their wild-type littermates. These results demonstrate that phosphorylation of the HS1 protein occurs downstream of GPVI stimulation and that HS1 plays a significant functional role in platelet activation downstream of GPVI and PARs.
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Affiliation(s)
- Bryan N Kahner
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, USA
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31
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Levine YC, Li GK, Michel T. Agonist-modulated regulation of AMP-activated protein kinase (AMPK) in endothelial cells. Evidence for an AMPK -> Rac1 -> Akt -> endothelial nitric-oxide synthase pathway. J Biol Chem 2007; 282:20351-64. [PMID: 17519230 DOI: 10.1074/jbc.m702182200] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The endothelial isoform of nitric-oxide synthase (eNOS), a key determinant of vascular homeostasis, is a calcium/calmodulin-dependent phosphoprotein regulated by diverse cell surface receptors. Vascular endothelial growth factor (VEGF) and sphingosine 1-phosphate (S1P) stimulate eNOS activity through Akt/phosphoinositide 3-kinase and calcium-dependent pathways. AMP-activated protein kinase (AMPK) also activates eNOS in endothelial cells; however, the molecular mechanisms linking agonist-mediated AMPK regulation with eNOS activation remain incompletely understood. We studied the role of AMPK in VEGF- and S1P-mediated eNOS activation and found that both agonists led to a striking increase in AMPK phosphorylation in pathways involving the calcium/calmodulin-dependent protein kinase kinase beta. Treatment with tyrosine kinase inhibitors or the phosphoinositide 3-kinase inhibitor wortmannin demonstrated differential effects of VEGF versus S1P. Small interfering RNA (siRNA)-mediated knockdown of AMPKalpha1or Akt1 impaired the stimulatory effects of both VEGF and S1P on eNOS activation. AMPKalpha1 knockdown impaired agonist-mediated Akt phosphorylation, whereas Akt1 knockdown did not affect AMPK activation, thus suggesting that AMPK lies upstream of Akt in the pathway leading from receptor activation to eNOS stimulation. Importantly, we found that siRNA-mediated knockdown of AMPKalpha1 abrogates agonist-mediated activation of the small GTPase Rac1. Conversely, siRNA-mediated knockdown of Rac1 decreased the agonist-mediated phosphorylation of AMPK substrates without affecting that of AMPK, implicating Rac1 as a molecular link between AMPK and Akt in agonist-mediated eNOS activation. Finally, siRNA-mediated knockdown of caveolin-1 significantly enhanced AMPK phosphorylation, suggesting that AMPK is negatively regulated by caveolin-1. Taken together, these results suggest that VEGF and S1P differentially regulate AMPK and establish a central role for an agonist-modulated AMPK --> Rac1 --> Akt axis in the control of eNOS in endothelial cells.
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Affiliation(s)
- Yehoshua C Levine
- Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA
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32
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Ping B, He X, Xia W, Lee DF, Wei Y, Yu D, Mills G, Shi D, Hung MC. Cytoplasmic expression of p21CIP1/WAF1 is correlated with IKKbeta overexpression in human breast cancers. Int J Oncol 2006; 29:1103-10. [PMID: 17016640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
Regulation of cytoplasmic p21CIP/WAF1 (p21) is of great clinical significance in molecular oncology due to its identification as an antiapoptotic factor, a poor survival predictor as well as a drug-resistance inducer. A retrospective study of the immunohistochemical (IHC) profiles of 128 human primary breast cancers showed that increased total and cytoplasmic p21 expression were highly associated with the expression of IkappaB kinase beta (IKKbeta), the major catalytic subunit of the IKK complex and another crucial player in tumorigenesis and drug resistance. The causal relationship study based on cultured cell lines, MDA-MB-453 and MCF-7, confirmed that IKKbeta overexpression did upregulate protein levels of total and cytoplasmic p21. Mechanistic investigation demonstrated that IKKbeta increased p21 expression through upregulation of p21 mRNA level. Moreover, by Western blotting, IKKbeta was found to be able to upregulate Akt phosphorylation on Ser 473. This novel finding indicated that IKKbeta could mediate cytoplasmic p21 accumulation via activation of its downstream target Akt, which was known to phosphorylate p21 and lead to cytoplasmic localization of p21.
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Affiliation(s)
- Bo Ping
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
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33
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Onoue T, Uchida D, Begum NM, Tomizuka Y, Yoshida H, Sato M. Epithelial-mesenchymal transition induced by the stromal cell-derived factor-1/CXCR4 system in oral squamous cell carcinoma cells. Int J Oncol 2006; 29:1133-8. [PMID: 17016644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
Epithelial-mesenchymal transition (EMT) refers to critical events occasionally observed during tumor progression, including invasion and metastasis, by which cancer cells acquire a fibroblast-like phenotype. Since the stromal cell-derived factor-1 (SDF-1)/CXCR4 system can facilitate lymph node metastasis in oral squamous cell carcinoma (SCC), we have explored the possibility that this system might be involved in EMT. Oral SCC cells, B88 and HNt, which have functional CXCR4 and lymph node metastatic potential, were found to lose their epithelial cell morphology due to SDF-1. In this context, the downregulation of epithelial markers, cytokeratin, E-cadherin and beta-catenin, and the upregulation of mesenchymal marker, vimentin and snail were detected. Furthermore, upregulation of vimentin by treatment with SDF-1 was impaired by phosphatidylinositol 3 kinase (PI3K) inhibitor Wortmannin, but not by mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor U0126. In the type I collagen embedding culture, SDF-1-treated B88 cells formed protruding extensions, but the effect was impaired by treatment with Wortmannin. These results suggested that EMT induced by the SDF-1/CXCR4 system might be involved in the lymph node metastasis of oral SCCs via activation of PI3K-Akt/PKB pathway.
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Affiliation(s)
- Tomitaro Onoue
- Second Department of Oral and Maxillofacial Surgery, Tokushima University School of Dentistry, Tokushima 770-8504, Japan
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34
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Qiu L, Zhou C, Sun Y, Di W, Scheffler E, Healey S, Kouttab N, Chu W, Wan Y. Crosstalk between EGFR and TrkB enhances ovarian cancer cell migration and proliferation. Int J Oncol 2006; 29:1003-11. [PMID: 16964397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Ovarian cancer remains the leading cause of fatality among all gynecologic cancers, although promising therapies are in the making. It has been speculated that metastasis is critical for ovarian cancer, and yet the molecular mechanisms of metastasis in ovarian cancer are poorly understood. Growth factors have been proven to play important roles in cell migration associated with metastasis, and inhibition of growth factor receptors and their distinct cell signaling pathways has been intensively studied, and yet the uncovered interaction or crosstalk among various growth factor receptors complicates this otherwise promising approach. We investigated the crosstalk between EGFR and TrkB, both of which have been known to be important in cell survival and migration in response to EGF and BDNF. Our results showed that both EGF and BDNF induced cell migration and cell proliferation in cultured human ovarian cancer cells (Caov3 cell line). EGF and BDNF transactivated TrkB and EGFR respectively, and activated downstream cell survival components such as Akt. EGFR and TrkB kinase inhibitors inhibited EGF- and BDNF-induced TrkB and EGFR activation and Akt phosphorylation, and cell proliferation and migration. Using EGFR knockout cells, we further demonstrated that EGFR is required for EGF-induced cell migration. Collectively, our data indicate that EGFR and TrkB crosstalk each other in response to EGF and BDNF, leading to cell survival pathway activation in ovarian cancer cells. Our data suggest that a combination of inhibitors of both receptors with cell survival pathway inhibitors would provide a better outcome in the clinical treatment of ovarian cancer.
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Affiliation(s)
- Lihua Qiu
- Department of OB/GYN, Renji Hospital, Shanghai Jiaotong University, Shanghai 200001, P.R. China
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35
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Shah DI, Singh M. Possible role of Akt to improve vascular endothelial dysfunction in diabetic and hyperhomocysteinemic rats. Mol Cell Biochem 2006; 295:65-74. [PMID: 16841179 DOI: 10.1007/s11010-006-9273-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Accepted: 06/26/2006] [Indexed: 10/24/2022]
Abstract
The study has been designed to investigate the effect of demethylasterroquinone B1 (DAQ B1), an activator of Akt, in diabetes mellitus (DM) and hyperhomocysteinemia (HHcy)-induced vascular endothelial dysfunction. Streptozotocin (55 mg kg(-1), i.v.) and methionine (1.7% w/w, p.o., 4 weeks) were administered to rats to produce DM (serum glucose >140 mg dl(-1)) and HHcy (serum homocysteine >10 microM), respectively. Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta and serum concentration of nitrite/nitrate. The expression of messenger RNA for p22phox and eNOS was assessed by reverse transcription-polymerase chain reaction. Serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion were estimated to assess oxidative stress. DAQ B1 (5 mg kg(-1), p.o.) or atorvastatin (30 mg kg(-1), p.o.) in diabetic and hyperhomocysteinemic rats significantly reduced serum glucose and homocysteine concentration. DAQ B1 or atorvastatin markedly improved acetylcholine-induced endothelium-dependent relaxation, vascular endothelial lining, serum nitrite/nitrate concentration and serum TBARS in diabetic and hyperhomocysteinemic rats. However, this ameliorative effect of DAQ B1 has been prevented by L-NAME (25 mg kg(-1), i.p.), an inhibitor of eNOS. Therefore, it may be concluded that DAQ B1-induced activation of Akt may activate eNOS and consequently reduce oxidative stress to improve vascular endothelial dysfunction.
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MESH Headings
- Acetylcholine/pharmacology
- Animals
- Aorta/drug effects
- Aorta/enzymology
- Aorta/ultrastructure
- Blood Glucose/metabolism
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/enzymology
- Diabetes Mellitus, Experimental/physiopathology
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/physiopathology
- Endothelium, Vascular/ultrastructure
- Gene Expression Regulation, Enzymologic/drug effects
- Homocysteine/blood
- Hyperhomocysteinemia/chemically induced
- Hyperhomocysteinemia/enzymology
- Hyperhomocysteinemia/physiopathology
- Male
- NADPH Oxidases/genetics
- NADPH Oxidases/metabolism
- Nitrates/blood
- Nitric Oxide Synthase Type III/genetics
- Nitric Oxide Synthase Type III/metabolism
- Nitrites/blood
- Proto-Oncogene Proteins c-akt/agonists
- Proto-Oncogene Proteins c-akt/metabolism
- Quinones/pharmacology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Superoxides/metabolism
- Thiobarbituric Acid Reactive Substances/analysis
- Vasodilation/drug effects
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Affiliation(s)
- Dhvanit I Shah
- Department of Pharmaceutical Sciences & Drug Research, Faculty of Medicine, Punjabi University, Patiala, 147002
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36
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Sharma D, Saxena NK, Vertino PM, Anania FA. Leptin promotes the proliferative response and invasiveness in human endometrial cancer cells by activating multiple signal-transduction pathways. Endocr Relat Cancer 2006; 13:629-40. [PMID: 16728588 PMCID: PMC2925427 DOI: 10.1677/erc.1.01169] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
An increase in the risk of cancer is one of the consequences of obesity. The predominant cancers associated with obesity have a hormonal basis and include breast, prostate, endometrium, colon and gall-bladder cancers. Leptin, the key player in the regulation of energy balance and body weight control also acts as a growth factor on certain organs in both normal and disease states. Therefore, it is plausible that leptin acts to promote cancer growth by acting as a mitogenic agent. However, a direct role for leptin in endometrial cancer has not been demonstrated. In this study, we analyzed the proliferative role of leptin and the mechanism(s) underlying this action in endometrial cancers which express both short and long isoforms of leptin receptors. Treatment with leptin resulted in increased proliferation of ECC1 and Ishikawa cells. The promotion of endometrial cancer cell proliferation by leptin involves activation of STAT3 and ERK2 signaling pathways. Moreover, leptin-induced phosphorylation of ERK2 and AKT was dependent on JAK/STAT activation. Therefore blocking its action at the JAK/STAT level could be a rational therapeutic strategy for endometrial carcinoma in obese patients. We also found that leptin potently induces invasion of endometrial cancer cells in a Matrigel invasion assay. Leptin-stimulated invasion was effectively blocked by pharmacological inhibitors of JAK/STAT (AG490) and phosphatidylinositol 3-kinase (LY294002). Taken together these data indicate that leptin promotes endometrial cancer growth and invasiveness and implicate the JAK/STAT and AKT pathways as critical mediators of leptin action. Our findings have potential clinical implications for endometrial cancer progression in obese patients.
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Affiliation(s)
- D Sharma
- Winship Cancer Institute, 1701 Uppergate Drive, Clinic C, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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