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Herbstein F, Sapochnik M, Attorresi A, Pollak C, Senin S, Gonilski-Pacin D, Ciancio Del Giudice N, Fiz M, Elguero B, Fuertes M, Müller L, Theodoropoulou M, Pontel LB, Arzt E. The SASP factor IL-6 sustains cell-autonomous senescent cells via a cGAS-STING-NFκB intracrine senescent noncanonical pathway. Aging Cell 2024:e14258. [PMID: 39012326 DOI: 10.1111/acel.14258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/16/2024] [Accepted: 06/05/2024] [Indexed: 07/17/2024] Open
Abstract
Senescent cells produce a Senescence-Associated Secretory Phenotype (SASP) that involves factors with diverse and sometimes contradictory activities. One key SASP factor, interleukin-6 (IL-6), has the potential to amplify cellular senescence in the SASP-producing cells in an autocrine action, while simultaneously inducing proliferation in the neighboring cells. The underlying mechanisms for the contrasting actions remain unclear. We found that the senescence action does not involve IL-6 secretion nor the interaction with the receptor expressed in the membrane but is amplified through an intracrine mechanism. IL-6 sustains intracrine senescence interacting with the intracellular IL-6 receptor located in anterograde traffic specialized structures, with cytosolic DNA, cGAS-STING, and NFκB activation. This pathway triggered by intracellular IL-6 significantly contributes to cell-autonomous induction of senescence and impacts in tumor growth control. Inactivation of IL-6 in somatotrophic senescent cells transforms them into strongly tumorigenic in NOD/SCID mice, while re-expression of IL-6 restores senescence control of tumor growth. The intracrine senescent IL-6 pathway is further evidenced in three human cellular models of therapy-induced senescence. The compartmentalization of the intracellular signaling, in contrast to the paracrine tumorigenic action, provides a pathway for IL-6 to sustain cell-autonomous senescent cells, driving the SASP, and opens new avenues for clinical consideration to senescence-based therapies.
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Affiliation(s)
- Florencia Herbstein
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Melanie Sapochnik
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Alejandra Attorresi
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Cora Pollak
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Sergio Senin
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - David Gonilski-Pacin
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Nicolas Ciancio Del Giudice
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Manuel Fiz
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Belén Elguero
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Mariana Fuertes
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität (LMU) München, Munich, Germany
| | - Lara Müller
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marily Theodoropoulou
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lucas B Pontel
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Eduardo Arzt
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Buenos Aires, Argentina
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität (LMU) München, Munich, Germany
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2
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Liang J, Hu F, Mao L, Qiu Y, Jiang F, Wang Q, Abulikemu K, Hong Y, Ge X, Kang X. Interleukin-37 inhibits desmoglein-3 endocytosis and keratinocyte dissociation via upregulation of Caveolin-1 and inhibition of the STAT3 pathway. J Eur Acad Dermatol Venereol 2023; 37:1920-1927. [PMID: 37262304 DOI: 10.1111/jdv.19239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 05/05/2023] [Indexed: 06/03/2023]
Abstract
BACKGROUND Pemphigus vulgaris (PV) is a potentially fatal autoimmune bullous disease primarily caused by acantholysis of keratinocytes attributed to pathogenic desmoglein-3 (Dsg3) autoantibodies. Interleukin-37 (IL-37) reportedly plays important roles in a variety of autoimmune diseases, but its role in PV is not clear. OBJECTIVES To investigate whether IL-37 plays a role in the occurrence and progression of PV. METHODS HaCaT keratinocytes were stimulated with anti-Dsg3 antibody to establish an in vitro PV model, which was defined as anti-Dsg3 group. Cells incubated with medium without anti-Dsg3 treatment were used as control. IL-37 was cultured with these cells infected with or without lentiviral vector shRNA-Caveolin-1 (sh-Cav-1-LV). Cell dissociation assay and immunocytofluorescence were performed to assess keratinocyte dissociation, keratin retraction and Dsg3 endocytosis. Real-time PCR was used to detect the mRNA level of Cav-1, and western blot was used to determine the protein expression of Cav-1, Dsg3, STAT3 and phosphorylated-STAT3 (p-STAT3). RESULTS The anti-Dsg3 group showed more cell debris, increased keratin retraction, increased Dsg3 endocytosis, reduced Cav-1 expression and co-localization than the control group, while IL-37 treatment neutralized all of these changes. Interestingly, Cav-1 knockdown supressed the inhibitory effect of IL-37 on keratinocyte dissociation and Dsg3 internalization. The protein expression of p-STAT3 was increased in keratinocytes of the PV model but decreased by IL-37. Re-activation of the STAT3 pathway by colivelin supressed the inhibitory effect of IL-37 on keratinocyte dissociation and Dsg3 internalization, along with upregulation of Cav-1 and Dsg3. CONCLUSIONS IL-37 inhibited keratinocyte dissociation and Dsg3 endocytosis in an in vitro PV model through the upregulating Cav-1 and inhibiting STAT3 pathway.
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Affiliation(s)
- Junqin Liang
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Fengxia Hu
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Lidan Mao
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Yun Qiu
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Fanhe Jiang
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
| | - Qian Wang
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Kailibinuer Abulikemu
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Yongzhen Hong
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Xinyu Ge
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
| | - Xiaojing Kang
- Department of Dermatology and Venereology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- Xinjiang Clinical Research Center for Dermatologic Diseases, Urumqi, China
- Xinjiang Key Laboratory of Dermatology Research (XJYS1707), Urumqi, China
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3
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Klabnik JL, Christenson LK, Gunewardena SSA, Pohler KG, Rispoli LA, Payton RR, Moorey SE, Neal Schrick F, Edwards JL. Heat-induced increases in body temperature in lactating dairy cows: impact on the cumulus and granulosa cell transcriptome of the periovulatory follicle. J Anim Sci 2022; 100:6620803. [PMID: 35772768 DOI: 10.1093/jas/skac121] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 04/05/2022] [Indexed: 12/21/2022] Open
Abstract
Cows acutely heat stressed after a pharmacologically induced luteinizing hormone (LH) surge had periovulatory changes in the follicular fluid proteome that may potentiate ovulation and impact oocyte developmental competence. Because the cellular origins of differentially abundant proteins were not known, we have examined the cumulus and granulosa cell transcriptomes from the periovulatory follicle in cows exhibiting varying levels of hyperthermia when occurring after the LH surge. After pharmacological induction of a dominant follicle, lactating dairy cows were administered gonadotropin releasing hormone (GnRH) and maintained in thermoneutral conditions (~67 temperature-humidity index [THI]) or heat stress conditions where THI was steadily increased for ~12 h (71 to 86 THI) and was sufficient to steadily elevate rectal temperatures. Cumulus-oocyte complexes and mural granulosa cells were recovered by transvaginal aspiration of dominant follicle content ~16 h after GnRH. Rectal temperature was used as a continuous, independent variable to identify differentially expressed genes (DEGs) increased or decreased per each 1 °C change in temperature. Cumulus (n = 9 samples) and granulosa (n = 8 samples) cells differentially expressed (false discovery rate [FDR] < 0.05) 25 and 87 genes, respectively. The majority of DEGs were upregulated by hyperthermia. Steady increases in THI are more like the "turning of a dial" than the "flipping of a switch." The moderate but impactful increases in rectal temperature induced modest fold changes in gene expression (<2-fold per 1 °C change in rectal temperature). Identification of cumulus DEGs involved in cell junctions, plasma membrane rafts, and cell-cycle regulation are consistent with marked changes in the interconnectedness and function of cumulus after the LH surge. Depending on the extent to which impacts may be occurring at the junctional level, cumulus changes may have indirect but impactful consequences on the oocyte as it undergoes meiotic maturation. Two granulosa cell DEGs have been reported by others to promote ovulation. Based on what is known, several other DEGs are suggestive of impacts on collagen formation or angiogenesis. Collectively these and other findings provide important insight regarding the extent to which the transcriptomes of the components of the periovulatory follicle (cumulus and mural granulosa cells) are affected by varying degrees of hyperthermia.
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Affiliation(s)
- Jessica L Klabnik
- Department of Animal Science, The University of Tennessee, Institute of Agriculture, AgResearch, Knoxville, TN 37996, USA
| | - Lane K Christenson
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Sumedha S A Gunewardena
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | | | | | - Rebecca R Payton
- Department of Animal Science, The University of Tennessee, Institute of Agriculture, AgResearch, Knoxville, TN 37996, USA
| | - Sarah E Moorey
- Department of Animal Science, The University of Tennessee, Institute of Agriculture, AgResearch, Knoxville, TN 37996, USA
| | - F Neal Schrick
- Department of Animal Science, The University of Tennessee, Institute of Agriculture, AgResearch, Knoxville, TN 37996, USA
| | - J Lannett Edwards
- Department of Animal Science, The University of Tennessee, Institute of Agriculture, AgResearch, Knoxville, TN 37996, USA
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Chichiarelli S, Altieri F, Paglia G, Rubini E, Minacori M, Eufemi M. ERp57/PDIA3: new insight. Cell Mol Biol Lett 2022; 27:12. [PMID: 35109791 PMCID: PMC8809632 DOI: 10.1186/s11658-022-00315-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/18/2022] [Indexed: 12/15/2022] Open
Abstract
The ERp57/PDIA3 protein is a pleiotropic member of the PDIs family and, although predominantly located in the endoplasmic reticulum (ER), has indeed been found in other cellular compartments, such as the nucleus or the cell membrane. ERp57/PDIA3 is an important research target considering it can be found in various subcellular locations. This protein is involved in many different physiological and pathological processes, and our review describes new data on its functions and summarizes some ligands identified as PDIA3-specific inhibitors.
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Affiliation(s)
- Silvia Chichiarelli
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy.
| | - Fabio Altieri
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy
| | - Giuliano Paglia
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy
| | - Elisabetta Rubini
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy.,Enrico Ed Enrica Sovena" Foundation, Rome, Italy
| | - Marco Minacori
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy
| | - Margherita Eufemi
- Department of Biochemical Sciences "A.Rossi-Fanelli", Sapienza University of Rome, P.le A.Moro 5, 00185, Rome, Italy
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5
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Niu M, Song S, Su Z, Wei L, Li L, Pu W, Zhao C, Ding Y, Wang J, Cao W, Gao Q, Wang H. Inhibition of heat shock protein (HSP) 90 reverses signal transducer and activator of transcription (STAT) 3-mediated muscle wasting in cancer cachexia mice. Br J Pharmacol 2021; 178:4485-4500. [PMID: 34265073 DOI: 10.1111/bph.15625] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/30/2021] [Accepted: 07/05/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Cancer cachexia is a common cause of death among cancer patients with no currently effective treatment available. In animal models, aberrant activation of STAT3 in skeletal muscle contributes to muscle wasting. However, clinically the factors regulating STAT3 activation and the molecular mechanisms involved remain incompletely understood. EXPERIMENTAL APPROACH The expression of HSP90 and the activation of STAT3 were detected in muscle from the patients with cancer cachexia or the tumour-bearing cachectic mice. HSP90 inhibitors, including 17DMAG (alvespimycin) and PU-H71, were administered to cachexic mice and cachexia parameters, weight loss, food intake, survival rate, body composition, serum metabolites, muscle wasting pathology and catabolic activation were analysed. The co-culture of C2C12 myotube cells with C26 conditioned media was performed to investigate the pathological mechanism involved in catabolic muscle wasting. The roles of HSP90, STAT3 and FOXO1 in myotube atrophy were explored via overexpression or knockdown. RESULTS An enhanced interaction between activated STAT3 and HSP90 in the skeletal muscle of cancer cachexia patients, is a crucial for the development of cachectic muscle wasting. HSP90 inhibitors 17DMAG and PU-H71 alleviated the muscle wasting in C26 and models or the myotube atrophy of C2C12 cells induced by C26 conditional medium. Prolonged STAT3 activation transactivated FOXO1 by binding directly to its promoter and triggered the muscle wasting in a FOXO1-dependent manner in muscle cells. CONCLUSION AND IMPLICATIONS The HSP90/STAT3/FOXO1 axis plays a critical role in cachectic muscle wasting, which might be a potential therapeutic target for the treatment of cancer cachexia.
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Affiliation(s)
- Mengyuan Niu
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Shiyu Song
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Zhonglan Su
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Lulu Wei
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Li Li
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Wenyuan Pu
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Chen Zhao
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Yibing Ding
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Jinglin Wang
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Wangsen Cao
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Qian Gao
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Hongwei Wang
- Center for Translational Medicine and Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China.,State Key Laboratory of Analytical Chemistry for Life Science, Medical School of Nanjing University, Nanjing, China
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Akhter MS, Uddin MA, Kubra KT, Barabutis N. Elucidation of the Molecular Pathways Involved in the Protective Effects of AUY-922 in LPS-Induced Inflammation in Mouse Lungs. Pharmaceuticals (Basel) 2021; 14:ph14060522. [PMID: 34072430 PMCID: PMC8226636 DOI: 10.3390/ph14060522] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 12/11/2022] Open
Abstract
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) cause thousands of deaths every year and are associated with high mortality rates (~40%) due to the lack of efficient therapies. Understanding the molecular mechanisms associated with those diseases will most probably lead to novel therapeutics. In the present study, we investigated the effects of the Hsp90 inhibitor AUY-922 in the major inflammatory pathways of mouse lungs. Mice were treated with LPS (1.6 mg/kg) via intratracheal instillation for 24 h and were then post-treated intraperitoneally with AUY-922 (10 mg/kg). The animals were examined 48 h after AUY-922 injection. LPS activated the TLR4-mediated signaling pathways, which in turn induced the release of different inflammatory cytokines and chemokines. AUY-922 suppressed the LPS-induced inflammation by inhibiting major pro-inflammatory pathways (e.g., JAK2/STAT3, MAPKs), and downregulated the IL-1β, IL-6, MCP-1 and TNFα. The expression levels of the redox regulator APE1/Ref1, as well as the DNA-damage inducible kinases ATM and ATR, were also increased after LPS treatment. Those effects were counteracted by AUY-922. Interestingly, this Hsp90 inhibitor abolished the LPS-induced pIRE1α suppression, a major component of the unfolded protein response. Our study elucidates the molecular pathways involved in the progression of murine inflammation and supports our efforts on the development of new therapeutics against lung inflammatory diseases and sepsis.
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7
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Loss of Hap1 selectively promotes striatal degeneration in Huntington disease mice. Proc Natl Acad Sci U S A 2020; 117:20265-20273. [PMID: 32747555 DOI: 10.1073/pnas.2002283117] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Huntington disease (HD) is an ideal model for investigating selective neurodegeneration, as expanded polyQ repeats in the ubiquitously expressed huntingtin (HTT) cause the preferential neurodegeneration in the striatum of the HD patient brains. Here we report that adeno-associated virus (AAV) transduction-mediated depletion of Hap1, the first identified huntingtin-associated protein, in adult HD knock-in (KI) mouse brains leads to selective neuronal loss in the striatum. Further, Hap1 depletion-mediated neuronal loss via AAV transduction requires the presence of mutant HTT. Rhes, a GTPase that is enriched in the striatum and sumoylates mutant HTT to mediate neurotoxicity, binds more N-terminal HTT when Hap1 is deficient. Consistently, more soluble and sumoylated N-terminal HTT is presented in HD KI mouse striatum when HAP1 is absent. Our findings suggest that both Rhes and Hap1 as well as cellular stress contribute to the preferential neurodegeneration in HD, highlighting the involvement of multiple factors in selective neurodegeneration.
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8
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Abstract
Fever has beneficial effects on immune responses; however, its impact on T cell polarization is poorly understood. In this issue of Immunity, Wang et al. show that fever acts through a T cell-intrinsic SMAD4-dependent mechanism that selectively drives Th17 cell differentiation and pathogenicity in autoimmunity.
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Affiliation(s)
- Sharon S Evans
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.
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9
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Alvarado-Ortiz E, Sarabia-Sánchez MÁ, García-Carrancá A. Molecular Mechanisms Underlying the Functions of Cellular Markers Associated with the Phenotype of Cancer Stem Cells. Curr Stem Cell Res Ther 2019; 14:405-420. [PMID: 30147013 DOI: 10.2174/1574888x13666180821154752] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/18/2018] [Accepted: 08/13/2018] [Indexed: 12/19/2022]
Abstract
Cancer Stem Cells (CSC) generally constitute a minor cellular population within tumors that exhibits some capacities of normal Stem Cells (SC). The existence of CSC, able to self-renew and differentiate, influences central aspects of tumor biology, in part because they can continue tumor growth, give rise to metastasis, and acquire drug and radioresistance, which open new avenues for therapeutics. It is well known that SC constantly interacts with their niche, which includes mesenchymal cells, extracellular ligands, and the Extra Cellular Matrix (ECM). These interactions regularly lead to homeostasis and maintenance of SC characteristics. However, the exact participation of each of these components for CSC maintenance is not clear, as they appear to be context- or cell-specific. In the recent past, surface cellular markers have been fundamental molecular tools for identifying CSC and distinguishing them from other tumor cells. Importantly, some of these cellular markers have been shown to possess functional roles that affect central aspects of CSC. Likewise, some of these markers can participate in regulating the interaction of CSC with their niche, particularly the ECM. We focused this review on the molecular mechanisms of surface cellular markers commonly employed to identify CSC, highlighting the signaling pathways and mechanisms involved in CSC-ECM interactions, through each of the cellular markers commonly used in the study of CSC, such as CD44, CD133, CD49f, CD24, CXCR4, and LGR5. Their presence does not necessarily implicate them in CSC biology.
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Affiliation(s)
- Eduardo Alvarado-Ortiz
- Programa de Maestría y Doctorado en Ciencias Biológicas, Facultad de Ciencias, Universidad Nacional Autónoma de México, México City, México.,Laboratory of Virus and Cancer, Unidad de Investigacion Biomedica en Cáncer, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico & Subdireccion de Investigacion Basica, Instituto Nacional de Cancerologia, Secretaria de Salud, Ciudad de Mexico, Mexico
| | - Miguel Á Sarabia-Sánchez
- Laboratory of Virus and Cancer, Unidad de Investigacion Biomedica en Cáncer, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico & Subdireccion de Investigacion Basica, Instituto Nacional de Cancerologia, Secretaria de Salud, Ciudad de Mexico, Mexico.,Programa de Maestría y Doctorado en Ciencias Bioquímicas, Facultad de Química, Universidad Nacional Autónoma de México, , México City, México
| | - Alejandro García-Carrancá
- Laboratory of Virus and Cancer, Unidad de Investigacion Biomedica en Cáncer, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico & Subdireccion de Investigacion Basica, Instituto Nacional de Cancerologia, Secretaria de Salud, Ciudad de Mexico, Mexico
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10
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Lee YC, Kurtova AV, Xiao J, Nikolos F, Hayashi K, Tramel Z, Jain A, Chen F, Chokshi M, Lee C, Bao G, Zhang X, Shen J, Mo Q, Jung SY, Rowley D, Chan KS. Collagen-rich airway smooth muscle cells are a metastatic niche for tumor colonization in the lung. Nat Commun 2019; 10:2131. [PMID: 31086186 PMCID: PMC6513865 DOI: 10.1038/s41467-019-09878-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/27/2019] [Indexed: 01/04/2023] Open
Abstract
Metastases account for the majority of cancer deaths. While certain steps of the metastatic cascade are well characterized, identification of targets to block this process remains a challenge. Host factors determining metastatic colonization to secondary organs are particularly important for exploration, as those might be shared among different cancer types. Here, we showed that bladder tumor cells expressing the collagen receptor, CD167a, responded to collagen I stimulation at the primary tumor to promote local invasion and utilized the same receptor to preferentially colonize at airway smooth muscle cells (ASMCs)—a rich source of collagen III in lung. Morphologically, COL3-CD167a-driven metastatic foci are uniquely distinct from typical lung alveolar metastatic lesions and exhibited activation of the CD167a-HSP90-Stat3 axis. Importantly, metastatic lung colonization could be abrogated using an investigational drug that attenuates Stat3 activity, implicating this seed-and-soil interaction as a therapeutic target for eliminating lung metastasis. Collagen is a dynamic component of both the tumor and metastatic niche. Here, the authors show that airway smooth muscle cells are a collagen III rich niche bladder cancer cells expressing CD167a, and Stat3 is a downstream target for abrogating these collagen III/CD167a-driven metastatic foci.
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Affiliation(s)
- Yu-Cheng Lee
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Antonina V Kurtova
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jing Xiao
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Fotis Nikolos
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Kazukuni Hayashi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Zoe Tramel
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Antrix Jain
- Department of Biochemistry and Molecular Biology, Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Fengju Chen
- Dan L Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Mithil Chokshi
- Department of Bioengineering, Rice University Houston, Houston, TX, 77030, USA
| | - Ciaran Lee
- Department of Bioengineering, Rice University Houston, Houston, TX, 77030, USA
| | - Gang Bao
- Department of Bioengineering, Rice University Houston, Houston, TX, 77030, USA
| | - Xiang Zhang
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jianjun Shen
- University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA
| | - Qianxing Mo
- Department of Biostatistics & Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, 33612, USA
| | - Sung Yun Jung
- Department of Biochemistry and Molecular Biology, Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX, 77030, USA
| | - David Rowley
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Keith Syson Chan
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA. .,Dan L Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA.
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11
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Li P, Wang J, Zou Y, Sun Z, Zhang M, Geng Z, Xu W, Wang D. Interaction of Hsp90AA1 with phospholipids stabilizes membranes under stress conditions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:457-465. [DOI: 10.1016/j.bbamem.2018.11.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 11/19/2018] [Accepted: 11/26/2018] [Indexed: 01/29/2023]
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12
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Osuna-Ramos JF, Reyes-Ruiz JM, Del Ángel RM. The Role of Host Cholesterol During Flavivirus Infection. Front Cell Infect Microbiol 2018; 8:388. [PMID: 30450339 PMCID: PMC6224431 DOI: 10.3389/fcimb.2018.00388] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/15/2018] [Indexed: 12/11/2022] Open
Abstract
In recent years the emergence and resurgence of arboviruses have generated a global health alert. Among arboviruses, Dengue (DENV), Zika (ZIKV), Yellow Fever (YFV), and West Nile (WNV) virus, belong to the genus Flavivirus, cause high viremia and occasionally fatal clinical disease in humans. Given the genetic austerity of the virus, they depend on cellular factors and organelles to complete its replication. One of the cellular components required for flavivirus infection is cholesterol. Cholesterol is an abundant lipid in biomembranes of eukaryotes cells and is necessary to maintain the cellular homeostasis. Recently, it has been reported, that cholesterol is fundamental during flavivirus infection in both mammal and insect vector models. During infection with DENV, ZIKV, YFV, and WNV the modulation of levels of host-cholesterol facilitates viral entry, replicative complexes formation, assembly, egress, and control of the interferon type I response. This modulation involves changes in cholesterol uptake with the concomitant regulation of cholesterol receptors as well as changes in cholesterol synthesis related to important modifications in cellular metabolism pathways. In view of the flavivirus dependence of cholesterol and the lack of an effective anti-flaviviral treatment, this cellular lipid has been proposed as a therapeutic target to treat infection using FDA-approved cholesterol-lowering drugs. This review aims to address the dependence of cholesterol by flaviviruses as well as the basis for anti flaviviral therapy using drugs which target is cholesterol synthesis or uptake.
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Affiliation(s)
- Juan Fidel Osuna-Ramos
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Ciudad de Mexico, Mexico
| | - José Manuel Reyes-Ruiz
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Ciudad de Mexico, Mexico
| | - Rosa Maria Del Ángel
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Ciudad de Mexico, Mexico
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13
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Geletu M, Mohan R, Arulanandam R, Berger-Becvar A, Nabi IR, Gunning PT, Raptis L. Reciprocal regulation of the Cadherin-11/Stat3 axis by caveolin-1 in mouse fibroblasts and lung carcinoma cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:794-802. [PMID: 29458077 DOI: 10.1016/j.bbamcr.2018.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/09/2018] [Accepted: 02/15/2018] [Indexed: 01/05/2023]
Abstract
Caveolin-1 (Cav1) is an integral plasma membrane protein and a complex regulator of signal transduction. The Signal Transducer and Activator of Transcription-3 (Stat3) is activated by a number of receptor and non-receptor tyrosine kinases and is positively implicated in cancer. Despite extensive efforts, the relationship between Cav1 and Stat3 has been a matter of controversy. We previously demonstrated that engagement of E- or N-cadherin or cadherin-11 cell to cell adhesion molecules, as occurs with confluence of cultured cells, triggers a dramatic increase in the levels of tyr705 phosphorylated i.e. activated Stat3, by a mechanism requiring the cRac1 small GTPase. Since confluence was not taken into account in previous studies, we revisited the question of the relationship between Cav1 and Stat3-ptyr705 in non-transformed mouse fibroblasts and in human lung carcinoma cells, by examining their effect at different cell densities. Our results unequivocally demonstrate that Cav1 downregulates cadherin-11, by a mechanism which requires the Cav1 scaffolding domain. This cadherin-11 downregulation, in turn, leads to a reduction in cRac1 and Stat3 activity levels. Furthermore, in a feedback loop possibly through p53 upregulation, Stat3 downregulation increases Cav1 levels. Our data reveal the presence of a potent, negative regulatory loop between Cav1 and cadherin-11/Stat3, leading to Stat3 inhibition and apoptosis.
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Affiliation(s)
- M Geletu
- Department of Biomedical and Molecular Sciences, Pathology and Molecular Medicine, Queen's University Cancer Research Institute, Queen's University, Kingston, Ontario K7L 3N6, Canada; Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Rd N., Mississauga, Ontario L5L 1C6, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada.
| | - R Mohan
- Department of Biomedical and Molecular Sciences, Pathology and Molecular Medicine, Queen's University Cancer Research Institute, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - R Arulanandam
- Department of Biomedical and Molecular Sciences, Pathology and Molecular Medicine, Queen's University Cancer Research Institute, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - A Berger-Becvar
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Rd N., Mississauga, Ontario L5L 1C6, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada
| | - I R Nabi
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - P T Gunning
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Rd N., Mississauga, Ontario L5L 1C6, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada
| | - L Raptis
- Department of Biomedical and Molecular Sciences, Pathology and Molecular Medicine, Queen's University Cancer Research Institute, Queen's University, Kingston, Ontario K7L 3N6, Canada
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14
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Wang X, Zhang Y, Zhao Y, Liang Y, Xiang C, Zhou H, Zhang H, Zhang Q, Qing H, Jiang B, Xiong H, Peng L. CD24 promoted cancer cell angiogenesis via Hsp90-mediated STAT3/VEGF signaling pathway in colorectal cancer. Oncotarget 2018; 7:55663-55676. [PMID: 27494878 PMCID: PMC5342444 DOI: 10.18632/oncotarget.10971] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 07/16/2016] [Indexed: 01/05/2023] Open
Abstract
CD24 is involved in tumor progression of various cancers, but the effects of CD24 on tumor angiogenesis in colorectal cancer are still unknown. We aimed to investigate the underlying mechanism and role of CD24 on colorectal cancer (CRC) angiogenesis. Our data showed that the microvessal density (MVD) was related to the expression of CD24 in primary and metastasis CRC. Silencing of CD24 could dramatically decrease human umbilical vein endothelial cell (HUVEC) migration, invasion and tubule formation, but trivially affected cell proliferation. We also mechanically showed that silencing CD24 could downregulate the expression of VEGF via inhibiting the phosphorylation and translocation of STAT3. Moreover, Hsp90 was identified as the down-interaction protein of CD24 with co-immunoprecipitation assay and systematic mass spectrometry. Immunofluorescence results showed Hsp90 partly co-localized with CD24 in CRC cell membrane and there was a positive correlation between CD24 and Hsp90 expression in CRC tissues. We gradually evidenced that Hsp90 modulated the stability and degradation of CD24 in a proteasome-depended manner, and transferred the signal transmission from CD24 to STAT3. 17-AAG, a specific Hsp90, could abrogate the CD24 induce- HUVEC migration, invasion and tubule formation in vitro and in vivo. Collectively, our results suggested that CD24 induced CRC angiogenesis in Hsp90-dependent manner and activated STAT3-mediated transcription of VEGF. We provided a new insight into the regulation mechanism of tumor angiogenesis by exploring the role of CD24 in angiogenesis.
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Affiliation(s)
- Xinying Wang
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Yu Zhang
- Department of Gastroenterology, The First People's Hospital of Yunnan Province, Kunming 65003, China
| | - Yingying Zhao
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Yanling Liang
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Cheng Xiang
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Huanyu Zhou
- Department of Ultrasound Imaging, 306 Hospital of PLA, Beijing 100101, China
| | - Hui Zhang
- Institute of Immunology and Molecular Medicine, Jining Medical College, Jining 272067, China.,Department of Medicine, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York 10029, NY, USA
| | - Qiang Zhang
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Haitao Qing
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Bo Jiang
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China
| | - Huabao Xiong
- Department of Medicine, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York 10029, NY, USA
| | - Liang Peng
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Guangdong Provincial Key Laboratory of Gastroenterology, Guangzhou 510515, China.,Department of Medicine, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York 10029, NY, USA
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15
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Alsaffar H, Martino N, Garrett JP, Adam AP. Interleukin-6 promotes a sustained loss of endothelial barrier function via Janus kinase-mediated STAT3 phosphorylation and de novo protein synthesis. Am J Physiol Cell Physiol 2018; 314:C589-C602. [PMID: 29351406 DOI: 10.1152/ajpcell.00235.2017] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Vascular leakage is a hallmark of the inflammatory response. Acute changes in endothelial permeability are due to posttranslational changes in intercellular adhesion and cytoskeleton proteins. However, little is known about the mechanisms leading to long-term changes in vascular permeability. Here, we show that interleukin-6 (IL-6) promotes an increase in endothelial monolayer permeability that lasts over 24 h and demonstrate that activation of Src and MEK/ERK pathways is required only for short-term increases in permeability, being dispensable after 2 h. In contrast, Janus kinase (JAK)-mediated STAT3 phosphorylation at Y705 (but not S727) and de novo synthesis of RNA and proteins are required for the sustained permeability increases. Loss of junctional localization of VE-cadherin and ZO-1 is evident several hours after the maximal IL-6 response, thus suggesting that these events are a consequence of IL-6 signaling, but not a cause of the increased permeability. Understanding the mechanisms involved in sustaining vascular permeability may prove crucial to allow us to directly target vascular leakage and minimize tissue damage, thus reducing the rates of mortality and chronic sequelae of excessive edema. Targeting endothelial-specific mechanisms regulating barrier function could provide a new therapeutic strategy to prevent vascular leakage while maintaining the immune response and other beneficial aspects of the inflammatory response that are required for bacterial clearance and tissue repair.
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Affiliation(s)
- Hiba Alsaffar
- Department of Molecular and Cellular Physiology, Albany Medical Center , Albany, New York
| | - Nina Martino
- Department of Molecular and Cellular Physiology, Albany Medical Center , Albany, New York
| | - Joshua P Garrett
- Department of Molecular and Cellular Physiology, Albany Medical Center , Albany, New York
| | - Alejandro P Adam
- Department of Molecular and Cellular Physiology, Albany Medical Center , Albany, New York.,Department of Ophthalmology, Albany Medical Center, Albany, New York
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16
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Appenheimer MM, Evans SS. Temperature and adaptive immunity. HANDBOOK OF CLINICAL NEUROLOGY 2018; 156:397-415. [DOI: 10.1016/b978-0-444-63912-7.00024-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
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17
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Niu Y, Xiang Y. An Overview of Biomembrane Functions in Plant Responses to High-Temperature Stress. FRONTIERS IN PLANT SCIENCE 2018; 9:915. [PMID: 30018629 PMCID: PMC6037897 DOI: 10.3389/fpls.2018.00915] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/08/2018] [Indexed: 05/03/2023]
Abstract
Biological membranes are highly ordered structures consisting of mosaics of lipids and proteins. Elevated temperatures can directly and effectively change the properties of these membranes, including their fluidity and permeability, through a holistic effect that involves changes in the lipid composition and/or interactions between lipids and specific membrane proteins. Ultimately, high temperatures can alter microdomain remodeling and instantaneously relay ambient cues to downstream signaling pathways. Thus, dynamic membrane regulation not only helps cells perceive temperature changes but also participates in intracellular responses and determines a cell's fate. Moreover, due to the specific distribution of extra- and endomembrane elements, the plasma membrane (PM) and membranous organelles are individually responsible for distinct developmental events during plant adaptation to heat stress. This review describes recent studies that focused on the roles of various components that can alter the physical state of the plasma and thylakoid membranes as well as the crucial signaling pathways initiated through the membrane system, encompassing both endomembranes and membranous organelles in the context of heat stress responses.
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Affiliation(s)
- Yue Niu
- *Correspondence: Yue Niu, Yun Xiang,
| | - Yun Xiang
- *Correspondence: Yue Niu, Yun Xiang,
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18
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Myocyte-Derived Hsp90 Modulates Collagen Upregulation via Biphasic Activation of STAT-3 in Fibroblasts during Cardiac Hypertrophy. Mol Cell Biol 2017; 37:MCB.00611-16. [PMID: 28031326 DOI: 10.1128/mcb.00611-16] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 12/16/2016] [Indexed: 01/01/2023] Open
Abstract
Signal transducer and activator of transcription 3 (STAT-3)-mediated signaling in relation to upregulated collagen expression in fibroblasts during cardiac hypertrophy is well defined. Our recent findings have identified heat shock protein 90 (Hsp90) to be a critical modulator of fibrotic signaling in cardiac fibroblasts in this disease milieu. The present study was therefore intended to analyze the role of Hsp90 in the STAT-3-mediated collagen upregulation process. Our data revealed a significant difference between in vivo and in vitro results, pointing to a possible involvement of myocyte-fibroblast cross talk in this process. Cardiomyocyte-targeted knockdown of Hsp90 in rats (Rattus norvegicus) in which the renal artery was ligated showed downregulated collagen synthesis. Furthermore, the results obtained with cardiac fibroblasts conditioned with Hsp90-inhibited hypertrophied myocyte supernatant pointed toward cardiomyocytes' role in the regulation of collagen expression in fibroblasts during hypertrophy. Our study also revealed a novel signaling mechanism where myocyte-derived Hsp90 orchestrates not only p65-mediated interleukin-6 (IL-6) synthesis but also its release in exosomal vesicles. Such myocyte-derived exosomes and myocyte-secreted IL-6 are responsible in unison for the biphasic activation of STAT-3 signaling in cardiac fibroblasts that culminates in excess collagen synthesis, leading to severely compromised cardiac function during cardiac hypertrophy.
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19
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Ye Q, Meng C, Shen Y, Ji J, Wang X, Zhou S, Jia L, Wang Y. Caveolin-1 Mediates Low-Intensity Ultrasound-Induced Apoptosis via Downregulation of Signal Transducer and Activator of Transcription 3 Phosphorylation in Laryngeal Carcinoma Cells. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:2253-2260. [PMID: 27289429 DOI: 10.1016/j.ultrasmedbio.2016.04.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 04/21/2016] [Accepted: 04/26/2016] [Indexed: 06/06/2023]
Abstract
Low-intensity ultrasound therapy has been found to be a potential tool in the management of malignant tumors in recent years. However, the molecular mechanism underlying low-intensity ultrasound-induced apoptosis is still not clear. In this study, we investigated the effects of low-intensity ultrasound-induced apoptosis in HEp-2 cells. We found that low-intensity ultrasound significantly induced apoptosis, and the expression level of caveolin-1 (Cav-1) was dramatically increased after ultrasound treatment of HEp-2 cells. After inhibiting the expression level of Cav-1 using siRNA transfection, we found that the cellular apoptosis induced by low-intensity ultrasound was significantly suppressed. In addition, inhibition of Cav-1 expression promoted phosphorylation of signal transducer and activator of transcription 3 (STAT3), suggesting that the STAT3 signaling pathway was involved in low-intensity ultrasound-induced apoptosis via Cav-1 regulation. Our results indicate that Cav-1/STAT3 signaling pathway may mediate low-intensity ultrasound-induced apoptosis, and this technology could potentially be used clinically for the treatment of cancers.
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Affiliation(s)
- Qingsheng Ye
- Medical Ultrasonic Engineering Department, Institute of Biomedical Engineering Chinese Academy of Medical Sciences, Tianjin, China
| | - Cuida Meng
- Department of Otolaryngology Head and Neck Surgery, China-Japan Union Hospital, Jilin University, Changchun, China
| | - Yannan Shen
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China
| | - Jianjun Ji
- Medical Ultrasonic Engineering Department, Institute of Biomedical Engineering Chinese Academy of Medical Sciences, Tianjin, China
| | - Xiaochun Wang
- Medical Ultrasonic Engineering Department, Institute of Biomedical Engineering Chinese Academy of Medical Sciences, Tianjin, China
| | - Sheng Zhou
- Medical Ultrasonic Engineering Department, Institute of Biomedical Engineering Chinese Academy of Medical Sciences, Tianjin, China
| | - Lili Jia
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China.
| | - Yanqun Wang
- Medical Ultrasonic Engineering Department, Institute of Biomedical Engineering Chinese Academy of Medical Sciences, Tianjin, China.
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20
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Hosoi T, Kohda T, Matsuzaki S, Ishiguchi M, Kuwamura A, Akita T, Tanaka J, Ozawa K. Key role of heat shock protein 90 in leptin-induced STAT3 activation and feeding regulation. Br J Pharmacol 2016; 173:2434-45. [PMID: 27205876 DOI: 10.1111/bph.13520] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND AND PURPOSE Leptin, an important regulator of the energy balance, acts on the brain to inhibit feeding. However, the mechanisms involved in leptin signalling have not yet been fully elucidated. Heat shock protein 90 (HSP90) is a molecular chaperone that is involved in regulating cellular homeostasis. In the present study, we investigated the possible involvement of HSP90 in leptin signal transduction. EXPERIMENTAL APPROACH HEK293 and SH-SY5Y cell lines stably transfected with the Ob-Rb leptin receptor (HEK293 Ob-Rb, SH-SY5Y Ob-Rb) were used in the present study. Phosphorylation of JAK2 and STAT3 was analysed by western blotting. An HSP90 inhibitor was administered i.c.v. into rats and their food intake was analysed. KEY RESULTS The knock-down of HSP90 in the HEK293 Ob-Rb cell line attenuated leptin-induced JAK2 and STAT3 signalling. Moreover, leptin-induced JAK2/STAT3 phosphorylation was markedly attenuated by the HSP90 inhibitors geldanamycin, radicicol and novobiocin. However, these effects were not mediated through previously known factors, which are known to be involved in the development of leptin resistance, such as suppressor of cytokine signalling 3 or endoplasmic reticulum stress. The infusion of an HSP90 inhibitor into the CNS blunted the anorexigenic actions of leptin in rats (male Wister rat). CONCLUSIONS AND IMPLICATIONS HSP90 may be a novel factor involved in leptin-mediated signalling that is linked to anorexia.
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Affiliation(s)
- Toru Hosoi
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Toshiko Kohda
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Syu Matsuzaki
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Mizuho Ishiguchi
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Ayaka Kuwamura
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tomoyuki Akita
- Department of Epidemiology, Infectious Disease Control and Prevention, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Junko Tanaka
- Department of Epidemiology, Infectious Disease Control and Prevention, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Koichiro Ozawa
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
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21
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Swaroop S, Sengupta N, Suryawanshi AR, Adlakha YK, Basu A. HSP60 plays a regulatory role in IL-1β-induced microglial inflammation via TLR4-p38 MAPK axis. J Neuroinflammation 2016; 13:27. [PMID: 26838598 PMCID: PMC4736186 DOI: 10.1186/s12974-016-0486-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 01/19/2016] [Indexed: 01/08/2023] Open
Abstract
Background IL-1β, also known as “the master regulator of inflammation”, is a potent pro-inflammatory cytokine secreted by activated microglia in response to pathogenic invasions or neurodegeneration. It initiates a vicious cycle of inflammation and orchestrates various molecular mechanisms involved in neuroinflammation. The role of IL-1β has been extensively studied in neurodegenerative disorders; however, molecular mechanisms underlying inflammation induced by IL-1β are still poorly understood. The objective of our study is the comprehensive identification of molecular circuitry involved in IL-1β-induced inflammation in microglia through protein profiling. Methods To achieve our aim, we performed the proteomic analysis of N9 microglial cells with and without IL-1β treatment at different time points. Expression of HSP60 in response to IL-1β administration was checked by quantitative real-time PCR, immunoblotting, and immunofluorescence. Interaction of HSP60 with TLR4 was determined by co-immunoprecipitation. Inhibition of TLR4 was done using TLR4 inhibitor to reveal its effect on IL-1β-induced inflammation. Further, effect of HSP60 knockdown and overexpression were assessed on the inflammation in microglia. Specific MAPK inhibitors were used to reveal the downstream MAPK exclusively involved in HSP60-induced inflammation in microglia. Results Total 21 proteins were found to be differentially expressed in response to IL-1β treatment in N9 microglial cells. In silico analysis of these proteins revealed unfolded protein response as one of the most significant molecular functions, and HSP60 turned out to be a key hub molecule. IL-1β induced the expression as well as secretion of HSP60 in extracellular milieu during inflammation of N9 cells. Secreted HSP60 binds to TLR4 and inhibition of TLR4 suppressed IL-1β-induced inflammation to a significant extent. Our knockdown and overexpression studies demonstrated that HSP60 increases the phosphorylation of ERK, JNK, and p38 MAPKs in N9 cells during inflammation. Specific inhibition of p38 by inhibitors suppressed HSP60-induced inflammation, thus pointed towards the major role of p38 MAPK rather than ERK1/2 and JNK in HSP60-induced inflammation. Furthermore, silencing of upstream modulator of p38, i.e., MEK3/6 also reduced HSP60-induced inflammation. Conclusions IL-1β induces expression of HSP60 in N9 microglial cells that further augments inflammation via TLR4-p38 MAPK axis. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0486-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shalini Swaroop
- National Brain Research Centre, Manesar, Haryana, 122051, India
| | | | | | - Yogita K Adlakha
- National Brain Research Centre, Manesar, Haryana, 122051, India.
| | - Anirban Basu
- National Brain Research Centre, Manesar, Haryana, 122051, India.
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22
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Hsp90 as a "Chaperone" of the Epigenome: Insights and Opportunities for Cancer Therapy. Adv Cancer Res 2015; 129:107-40. [PMID: 26916003 DOI: 10.1016/bs.acr.2015.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The cellular functions of Hsp90 have historically been attributed to its ability to chaperone client proteins involved in signal transduction. Although numerous stimuli and the signaling cascades they activate contribute to cancer progression, many of these pathways ultimately require transcriptional effectors to elicit tumor-promoting effects. Despite this obvious connection, the majority of studies evaluating Hsp90 function in malignancy have focused upon its regulation of cytosolic client proteins, and particularly members of receptor and/or kinase families. However, in recent years, Hsp90 has emerged as a pivotal orchestrator of nuclear events. Discovery of an expanding repertoire of Hsp90 clients has illuminated a vital role for Hsp90 in overseeing nuclear events and influencing gene transcription. Hence, this chapter will cast a spotlight upon several regulatory themes involving Hsp90-dependent nuclear functions. Highlighted topics include a summary of chaperone-dependent regulation of key transcription factors (TFs) and epigenetic effectors in malignancy, as well as a discussion of how the complex interplay among a subset of these TFs and epigenetic regulators may generate feed-forward loops that further support cancer progression. This chapter will also highlight less recognized indirect mechanisms whereby Hsp90-supported signaling may impinge upon epigenetic regulation. Finally, the relevance of these nuclear events is discussed within the framework of Hsp90's capacity to enable phenotypic variation and drug resistance. These newly acquired insights expanding our understanding of Hsp90 function support the collective notion that nuclear clients are major beneficiaries of Hsp90 action, and their impairment is likely responsible for many of the anticancer effects elicited by Hsp90-targeted approaches.
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23
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Lee MKS, Moore XL, Fu Y, Al-Sharea A, Dragoljevic D, Fernandez-Rojo MA, Parton R, Sviridov D, Murphy AJ, Chin-Dusting JPF. High-density lipoprotein inhibits human M1 macrophage polarization through redistribution of caveolin-1. Br J Pharmacol 2015; 173:741-51. [PMID: 26332942 DOI: 10.1111/bph.13319] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 08/19/2015] [Accepted: 08/25/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Monocyte-derived macrophages are critical in the development of atherosclerosis and can adopt a wide range of functional phenotypes depending on their surrounding milieu. High-density lipoproteins (HDLs) have many cardio-protective properties including potent anti-inflammatory effects. We investigated the effects of HDL on human macrophage phenotype and the mechanisms by which these occur. EXPERIMENTAL APPROACH Human blood monocytes were differentiated into macrophages in the presence or absence of HDL and were then induced to either an inflammatory macrophage (M1) or anti-inflammatory macrophage (M2) phenotype using LPS and IFN-γ or IL-4, respectively. KEY RESULTS HDL inhibited the induction of macrophages to an M1-phenotype, as evidenced by a decrease in the expression of M1-specific cell surface markers CD192 and CD64, as well as M1-associated inflammatory genes TNF-α, IL-6 and MCP-1 (CCL2). HDL also inhibited M1 function by reducing the production of ROS. In contrast, HDL had no effect on macrophage induction to the M2-phenotype. Similarly, methyl-β-cyclodextrin, a non-specific cholesterol acceptor also suppressed the induction of M1 suggesting that cholesterol efflux is important in this process. Furthermore, HDL decreased membrane caveolin-1 in M1 macrophages. We confirmed that caveolin-1 is required for HDL to inhibit M1 induction as bone marrow-derived macrophages from caveolin-1 knockout mice continued to polarize into M1-phenotype despite the presence of HDL. Moreover, HDL decreased ERK1/2 and STAT3 phosphorylation in M1 macrophages. CONCLUSIONS AND IMPLICATIONS We concluded that HDL reduces the induction of macrophages to the inflammatory M1-phenotype via redistribution of caveolin-1, preventing the activation of ERK1/2 and STAT3.
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Affiliation(s)
- Man K S Lee
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Xiao-Lei Moore
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Yi Fu
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Annas Al-Sharea
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Dragana Dragoljevic
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Manuel A Fernandez-Rojo
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Robert Parton
- Institute for Molecular Bioscience and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Australia
| | - Dmitri Sviridov
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Andrew J Murphy
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Immunology, Monash University, Melbourne, Australia
| | - Jaye P F Chin-Dusting
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
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Cell-intrinsic adaptation of lipid composition to local crowding drives social behaviour. Nature 2015; 523:88-91. [DOI: 10.1038/nature14429] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 03/25/2015] [Indexed: 12/20/2022]
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25
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Munday DC, Howell G, Barr JN, Hiscox JA. Proteomic analysis of mitochondria in respiratory epithelial cells infected with human respiratory syncytial virus and functional implications for virus and cell biology. ACTA ACUST UNITED AC 2014; 67:300-18. [PMID: 25533920 DOI: 10.1111/jphp.12349] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 10/12/2014] [Indexed: 12/27/2022]
Abstract
OBJECTIVES The aim of this study was to quantitatively characterise the mitochondrial proteome of airway epithelial cells infected with human respiratory syncytial virus (HRSV), a major cause of paediatric illness. METHODS Quantitative proteomics, underpinned by stable isotope labelling with amino acids in cell culture, coupled to LC-MS/MS, was applied to mitochondrial fractions prepared from HRSV-infected and mock-infected cells 12 and 24 h post-infection. Datasets were analysed using ingenuity pathway analysis, and the results were validated and characterised using bioimaging, targeted inhibition and gene depletion. KEY FINDINGS The data quantitatively indicated that antiviral signalling proteins converged on mitochondria during HRSV infection. The mitochondrial receptor protein Tom70 was found to act in an antiviral manner, while its chaperone, Hsp90, was confirmed to be a positive viral factor. Proteins associated with different organelles were also co-enriched in the mitochondrial fractions from HRSV-infected cells, suggesting that alterations in organelle dynamics and membrane associations occur during virus infection. CONCLUSIONS Protein and pathway-specific alterations occur to the mitochondrial proteome in a spatial and temporal manner during HRSV infection, suggesting that this organelle may have altered functions. These could be targeted as part of potential therapeutic strategies to disrupt virus biology.
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Affiliation(s)
- Diane C Munday
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
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Bocchini CE, Kasembeli MM, Roh SH, Tweardy DJ. Contribution of chaperones to STAT pathway signaling. JAKSTAT 2014; 3:e970459. [PMID: 26413421 DOI: 10.4161/21623988.2014.970459] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 09/21/2014] [Accepted: 09/25/2014] [Indexed: 12/27/2022] Open
Abstract
Aberrant STAT signaling is associated with the development and progression of many cancers and immune related diseases. Recent findings demonstrate that proteostasis modulators under clinical investigation for cancer therapy have a significant impact on STAT signaling, which may be critical for mediating their anti-cancer effects. Chaperones are critical for protein folding, stability and function and, thus, play an essential role in the maintenance of proteostasis. In this review we discuss the role of chaperones in STAT and tyrosine kinase (TK) protein folding, modulation of STAT and TK activity, and degradation of TKs. We highlight the important role of chaperones in STAT signaling, and how this knowledge has provided a framework for the development of new therapeutic avenues of targeting STAT signaling related pathologies.
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Affiliation(s)
- Claire E Bocchini
- Section of Infectious Disease; Department of Pediatrics; Baylor College of Medicine ; Houston, TX USA
| | - Moses M Kasembeli
- Section of Infectious Disease; Department of Medicine; Baylor College of Medicine ; Houston, TX USA
| | - Soung-Hun Roh
- Department of Biochemistry & Molecular Biology; Baylor College of Medicine ; Houston, TX USA
| | - David J Tweardy
- Section of Infectious Disease; Department of Medicine; Baylor College of Medicine ; Houston, TX USA ; Department of Biochemistry & Molecular Biology; Baylor College of Medicine ; Houston, TX USA ; Department of Molecular & Cellular Biology; Baylor College of Medicine ; Houston, TX USA
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Zuo J, Brewer DS, Arlt VM, Cooper CS, Phillips DH. Benzo pyrene-induced DNA adducts and gene expression profiles in target and non-target organs for carcinogenesis in mice. BMC Genomics 2014; 15:880. [PMID: 25297811 PMCID: PMC4209037 DOI: 10.1186/1471-2164-15-880] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 09/23/2014] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Gene expression changes induced by carcinogens may identify differences in molecular function between target and non-target organs. Target organs for benzo[a]pyrene (BaP) carcinogenicity in mice (lung, spleen and forestomach) and three non-target organs (liver, colon and glandular stomach) were investigated for DNA adducts by 32P-postlabelling, for gene expression changes by cDNA microarray and for miRNA expression changes by miRNA microarray after exposure of animals to BaP. RESULTS BaP-DNA adduct formation occurred in all six organs at levels that did not distinguish between target and non-target. cDNA microarray analysis showed a variety of genes modulated significantly by BaP in the six organs and the overall gene expression patterns were tissue specific. Gene ontology analysis also revealed that BaP-induced bioactivities were tissue specific; eight genes (Tubb5, Fos, Cdh1, Cyp1a1, Apc, Myc, Ctnnb1 and Cav) showed significant expression difference between three target and three non-target organs. Additionally, several gene expression changes, such as in Trp53 activation and Stat3 activity suggested some similarities in molecular mechanisms in two target organs (lung and spleen), which were not found in the other four organs. Changes in miRNA expression were generally tissue specific, involving, in total, 21/54 miRNAs significantly up- or down-regulated. CONCLUSIONS Altogether, these findings showed that DNA adduct levels and early gene expression changes did not fully distinguish target from non-target organs. However, mechanisms related to early changes in p53, Stat3 and Wnt/β-catenin pathways may play roles in defining BaP organotropism.
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Affiliation(s)
- Jie Zuo
- />Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford University, Oxford, OX3 9DS UK
| | - Daniel S Brewer
- />School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ UK
| | - Volker M Arlt
- />Analytical and Environmental Sciences Division, MRC-PHE Centre for Environment & Health, King’s College London, Franklin-Wilkins Building, 150 Stamford Street, London, SE1 9NH UK
| | - Colin S Cooper
- />The Medical School, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ UK
| | - David H Phillips
- />Analytical and Environmental Sciences Division, MRC-PHE Centre for Environment & Health, King’s College London, Franklin-Wilkins Building, 150 Stamford Street, London, SE1 9NH UK
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Blumert C, Kalkhof S, Brocke-Heidrich K, Kohajda T, von Bergen M, Horn F. Analysis of the STAT3 interactome using in-situ biotinylation and SILAC. J Proteomics 2013; 94:370-86. [PMID: 24013128 DOI: 10.1016/j.jprot.2013.08.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 08/01/2013] [Accepted: 08/26/2013] [Indexed: 12/28/2022]
Abstract
UNLABELLED Signal transducer and activator of transcription 3 (STAT3) is activated by a variety of cytokines and growth factors. To generate a comprehensive data set of proteins interacting specifically with STAT3, we applied stable isotope labeling with amino acids in cell culture (SILAC). For high-affinity pull-down using streptavidin, we fused STAT3 with a short peptide tag allowing biotinylation in situ (bio-tag), which did not affect STAT3 functions. By this approach, 3642 coprecipitated proteins were detected in human embryonic kidney-293 cells. Filtering using statistical and functional criteria finally extracted 136 proteins as putative interaction partners of STAT3. Both, a physical interaction network analysis and the enrichment of known and predicted interaction partners suggested that our filtering criteria successfully enriched true STAT3 interactors. Our approach identified numerous novel interactors, including ones previously predicted to associate with STAT3. By reciprocal coprecipitation, we were able to verify the physical association between STAT3 and selected interactors, including the novel interaction with TOX4, a member of the TOX high mobility group box family. Applying the same method, we next investigated the activation-dependency of the STAT3 interactome. Again, we identified both known and novel interactions. Thus, our approach allows to study protein-protein interaction effectively and comprehensively. BIOLOGICAL SIGNIFICANCE The location, activity, function, degradation, and synthesis of proteins are significantly regulated by interactions of proteins with other proteins, biopolymers and small molecules. Thus, the comprehensive characterization of interactions of proteins in a given proteome is the next milestone on the path to understanding the biochemistry of the cell. In order to generate a comprehensive interactome dataset of proteins specifically interacting with a selected bait protein, we fused our bait protein STAT3 with a short peptide tag allowing biotinylation in situ (bio-tag). This bio-tag allows an affinity pull-down using streptavidin but affected neither the activation of STAT3 by tyrosine phosphorylation nor its transactivating potential. We combined SILAC for accurate relative protein quantification, subcellular fractionation to increase the coverage of interacting proteins, high-affinity pull-down and a stringent filtering method to successfully analyze the interactome of STAT3. With our approach we confirmed several already known and identified numerous novel STAT3 interactors. The approach applied provides a rapid and effective method, which is broadly applicable for studying protein-protein interactions and their dependency on post-translational modifications.
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Affiliation(s)
- Conny Blumert
- Institute of Clinical Immunology, Medical Faculty, University of Leipzig, Johannisallee 30, 04103 Leipzig, Germany; Fraunhofer Institute for Cell Therapy and Immunology, Perlickstrasse 1, 04103 Leipzig, Germany
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Proteomic profiling of rabbit embryonic stem cells derived from parthenotes and fertilized embryos. PLoS One 2013; 8:e67772. [PMID: 23861804 PMCID: PMC3701598 DOI: 10.1371/journal.pone.0067772] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 05/22/2013] [Indexed: 11/19/2022] Open
Abstract
Rabbit embryonic stem (rES) cells can be derived from various sources of embryos. However, understanding of the gene expression profile, which distincts embryonic stem (ES) cells from other cell types, is still extremely limited. In this study, we compared the protein profiles of three independent lines of rabbit cells, i.e., fibroblasts, fertilized embryo-derived stem (f-rES) cells, and parthenote-derived ES (p-rES) cells. Proteomic analyses were performed using two-dimensional gel electrophoresis (2-DE) and mass spectrometry. Collectively, the expression levels of 100 out of 284 protein spots differed significantly among these three cell types (p<0.05). Of those differentially expressed spots, 91% were identified in the protein database and represented 63 distinct proteins. Proteins with known identities are mainly localized in the cytoplasmic compartments (48%), nucleus (14%), and cytoskeletal machineries (13%). These proteins were majorly involved in biological functions of energy and metabolic pathways (25%), cell growth and maintenance (25%), signal transduction (14%), and protein metabolisms (10%). When protein expression levels among cell types were compared, six proteins associated with a variety of cellular activities, including structural constituents of the cytoskeleton (tubulins), structural molecule (KRT8), catalytic molecules (α-enolase), receptor complex scaffold (14-3-3 protein sigma), microfilament motor proteins (Myosin-9), and heat shock protein (HSP60), were found highly expressed in p-rES cells. Two proteins related to HSP activity and structural constituent of cytoskeleton in f-rES cells, and one structural molecule activity protein in fibroblasts showed significantly higher expression levels (p<0.05). Marker protein expressions in f-rES and p-rES cells were further confirmed by Western blotting and immunocytochemical staining. This study demonstrated unique proteomic profiles of the three rabbit cell types and revealed some novel proteins differentially expressed between f-rES and p-rES cells. These analyses provide insights into rES cell biology and would invite more in-depth studies toward rES cell applications.
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Beraldo FH, Soares IN, Goncalves DF, Fan J, Thomas AA, Santos TG, Mohammad AH, Roffé M, Calder MD, Nikolova S, Hajj GN, Guimaraes AL, Massensini AR, Welch I, Betts DH, Gros R, Drangova M, Watson AJ, Bartha R, Prado VF, Martins VR, Prado MAM. Stress-inducible phosphoprotein 1 has unique cochaperone activity during development and regulates cellular response to ischemia via the prion protein. FASEB J 2013; 27:3594-607. [PMID: 23729591 DOI: 10.1096/fj.13-232280] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Stress-inducible phosphoprotein 1 (STI1) is part of the chaperone machinery, but it also functions as an extracellular ligand for the prion protein. However, the physiological relevance of these STI1 activities in vivo is unknown. Here, we show that in the absence of embryonic STI1, several Hsp90 client proteins are decreased by 50%, although Hsp90 levels are unaffected. Mutant STI1 mice showed increased caspase-3 activation and 50% impairment in cellular proliferation. Moreover, placental disruption and lack of cellular viability were linked to embryonic death by E10.5 in STI1-mutant mice. Rescue of embryonic lethality in these mutants, by transgenic expression of the STI1 gene, supported a unique role for STI1 during embryonic development. The response of STI1 haploinsufficient mice to cellular stress seemed compromised, and mutant mice showed increased vulnerability to ischemic insult. At the cellular level, ischemia increased the secretion of STI1 from wild-type astrocytes by 3-fold, whereas STI1 haploinsufficient mice secreted half as much STI1. Interesting, extracellular STI1 prevented ischemia-mediated neuronal death in a prion protein-dependent way. Our study reveals essential roles for intracellular and extracellular STI1 in cellular resilience.
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Affiliation(s)
- Flavio H Beraldo
- Robarts Research Institute, University of Western Ontario, London, Ontario, Canada
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Sehgal PB. Non-genomic STAT5-dependent effects at the endoplasmic reticulum and Golgi apparatus and STAT6-GFP in mitochondria. JAKSTAT 2013; 2:e24860. [PMID: 24470974 PMCID: PMC3894245 DOI: 10.4161/jkst.24860] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 04/28/2013] [Accepted: 04/29/2013] [Indexed: 11/19/2022] Open
Abstract
STAT protein species are well-known as transcription factors that regulate nuclear gene expression. Recent novel lines of research suggest new non-genomic functions of STAT5A/B and STAT6. It was discovered in human pulmonary arterial endothelial cells that STAT5A, including STAT5A-GFP, constitutively associated with the Golgi apparatus, and both STAT5A and B with the endoplasmic reticulum. Acute siRNA-mediated knockdown of STAT5A/B led to the rapid development of a dramatic cystic change in the endoplasmic reticulum (ER) characterized by deposition of the ER structural protein reticulon-4 (RTN4; also called Nogo-B) and the ER-resident GTPase atlastin-3 (ATL3) along cyst membranes and cyst-zone boundaries, accompanied by Golgi fragmentation. Functional consequences included reduced anterograde trafficking, an ER stress response (increased GRP78/BiP) and eventual mitochondrial fragmentation. This phenotype was "non-genomic" in that it was elicited in enucleated cytoplasts. In cross-immunopanning assays STAT5A and B species associated with ATL3, and the ER-lumen spacer CLIMP63 (also called cytoskeleton-associated protein 4, CKAP4) but not RTN4. From a disease significance perspective we posit that STAT5, which is known to be affected by estradiol-17β and prolactin, represents the gender-sensitive determinant in the pathogenesis of idiopathic pulmonary hypertension (IPAH), a disease which includes ER/Golgi dysfunctions but with a 2- to 4-fold higher prevalence in postpubertal women. A separate line of recent research produced evidence for the association of STAT6-GFP, but not STAT3-GFP, STAT3-DsRed, or STAT3-Flag, with mitochondria in live-cell, immunofluorescence, and immunoelectron microscopy. An N-terminal truncation of STAT6-GFP (1-459), which lacked the SH2 domain and Tyr-phosphorylation site, constitutively associated with mitochondria. Thus, the emergent new of biology STAT proteins includes non-genomic roles-structurally and functionally-in the three closely related membrane organelles consisting of the endoplasmic reticulum, Golgi apparatus, and mitochondria.
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Affiliation(s)
- Pravin B Sehgal
- Departments of Cell Biology & Anatomy, and Medicine; New York Medical College; Valhalla, NY USA
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Nespital T, Strous GJ. The Jak/STAT signaling pathway is downregulated at febrile temperatures. PLoS One 2012; 7:e49374. [PMID: 23166650 PMCID: PMC3498154 DOI: 10.1371/journal.pone.0049374] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 10/08/2012] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The Janus family of kinases (JAKs), Jak1, Jak2, Jak3, and Tyk2, constitute a subgroup of non-receptor protein tyrosine kinases. Upon cytokine binding, the receptor-associated kinases are activated and phosphorylate tyrosine residues in their cognate cytokine receptors. Their activities are controlled at several levels and include cellular concentration, auto-activation, and degradation. PRINCIPAL FINDINGS Our findings show that elevated temperatures in the fever range irreversibly aggregate Jak2 and considerably reduce functional Jak2 protein levels. Jak2 synthesis remains unaltered. We observed that also the protein level of the signal transducer and activator of transcription, STAT5b, is transiently decreased at temperatures above 37°C. Consequently, the signaling response, e.g. via the growth hormone receptor, is reduced. CONCLUSIONS/SIGNIFICANCE These findings predict that elevated body temperatures lower the responsiveness of cytokine receptors.
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Affiliation(s)
| | - Ger J. Strous
- Department of Cell Biology and Institute of Biomembranes, University Medical Center Utrecht, Utrecht, The Netherlands
- * E-mail:
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Fu J, Chen D, Zhao B, Zhao Z, Zhou J, Xu Y, Xin Y, Liu C, Luo L, Yin Z. Luteolin induces carcinoma cell apoptosis through binding Hsp90 to suppress constitutive activation of STAT3. PLoS One 2012; 7:e49194. [PMID: 23145121 PMCID: PMC3493516 DOI: 10.1371/journal.pone.0049194] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Accepted: 10/04/2012] [Indexed: 11/28/2022] Open
Abstract
Background Abnormal activity of STAT3 is associated with a number of human malignancies. Hsp90 plays a central role in stabilizing newly synthesized proteins and participates in maintaining the functional competency of a number of signaling transducers involved in cell growth, survival and oncogenesis, such as STAT3. Hsp90 interacts with STAT3 and stabilizes Tyr-phosphorylated STAT3. It has been reported that luteolin possesses anticancer activity through degradation of Tyr705-phosphorylated STAT3. Methodology/Principal Findings We found that overexpression of Hsp90 inhibited luteolin-induced degradation of Tyr705-phosphorylated STAT3 and luteolin also reduced the levels of some other Hsp90 interacting proteins. Results from co-immunoprecipitation and immunoblot analysis demonstrated that luteolin prevented the association between Hsp90 and STAT3 and induced both Tyr705- and Ser727-phosphorylated STAT3 degradation through proteasome-dependent pathway. The molecular modeling analysis with CHARMm–Discovery Studio 2.1(DS 2.1) indicated that luteolin could bind to the ATP-binding pocket of Hsp90. SPR technology-based binding assay confirmed the association between luteolin and Hsp90. ATP-sepharose binding assay displayed that luteolin inhibited Hsp90-ATP binding. Conclusions/Significance Luteolin promoted the degradation of Tyr705- and Ser727-phosphorylated STAT3 through interacting with Hsp90 and induced apoptosis of cancer cells. This study indicated that luteolin may act as a potent HSP90 inhibitor in antitumor strategies.
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Affiliation(s)
- Jin Fu
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Dan Chen
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, People’s Republic of China
| | - Bo Zhao
- College of Chemistry and Material Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Zhihui Zhao
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Jiahong Zhou
- Center for Analysis and Test, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Yimiao Xu
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Yinqiang Xin
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Chang Liu
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
| | - Lan Luo
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, People’s Republic of China
- * E-mail: (ZMY); (LL)
| | - Zhimin Yin
- Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, People’s Republic of China
- * E-mail: (ZMY); (LL)
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Szczepanek K, Lesnefsky EJ, Larner AC. Multi-tasking: nuclear transcription factors with novel roles in the mitochondria. Trends Cell Biol 2012; 22:429-37. [PMID: 22705015 DOI: 10.1016/j.tcb.2012.05.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 05/07/2012] [Accepted: 05/15/2012] [Indexed: 01/06/2023]
Abstract
Coordinated responses between the nucleus and mitochondria are essential for the maintenance of homeostasis. For over 15 years, pools of nuclear transcription factors (TFs), such as p53 and nuclear hormone receptors, have been observed in the mitochondria. The contribution of the mitochondrial pool of these TFs to their well-defined biological actions is in some cases clear and in others not well understood. Recently, a small mitochondrial pool of the TF signal transducer and activator of transcription factor 3 (STAT3) was shown to modulate the activity of the electron transport chain (ETC). The mitochondrial function of STAT3 encompasses both its biological actions in the heart as well as its oncogenic effects. This review highlights advances in our understanding of how mitochondrial pools of nuclear TFs may influence the function of this organelle.
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Affiliation(s)
- Karol Szczepanek
- Department of Biochemistry and Molecular Biology, and Massey Cancer Center, Virginia Commonwealth University, Richmond, VA 23298, USA
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Kim YD, Kim YH, Cho YM, Kim DK, Ahn SW, Lee JM, Chanda D, Shong M, Lee CH, Choi HS. Metformin ameliorates IL-6-induced hepatic insulin resistance via induction of orphan nuclear receptor small heterodimer partner (SHP) in mouse models. Diabetologia 2012; 55:1482-94. [PMID: 22349108 DOI: 10.1007/s00125-012-2494-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 01/09/2012] [Indexed: 01/14/2023]
Abstract
AIMS/HYPOTHESIS IL-6 is a proinflammatory cytokine associated with the pathogenesis of hepatic diseases. Metformin is an anti-diabetic drug used for the treatment of type 2 diabetes, and orphan nuclear receptor small heterodimer partner (SHP, also known as NR0B2), a transcriptional co-repressor, plays an important role in maintaining metabolic homeostasis. Here, we demonstrate that metformin-mediated activation of AMP-activated protein kinase (AMPK) increases SHP protein production and regulates IL-6-induced hepatic insulin resistance. METHODS We investigated metformin-mediated SHP production improved insulin resistance through the regulation of an IL-6-dependent pathway (involving signal transducer and activator of transcription 3 [STAT3] and suppressor of cytokine signalling 3 [SOCS3]) in both Shp knockdown and Shp null mice. RESULTS IL-6-induced STAT3 transactivation and SOCS3 production were significantly repressed by metformin, adenoviral constitutively active AMPK (Ad-CA-AMPK), and adenoviral SHP (Ad-SHP), but not in Shp knockdown, or with the adenoviral dominant negative form of AMPK (Ad-DN-AMPK). Chromatin immunoprecipitation (ChIP), co-immunoprecipitation (Co-IP) and protein localisation studies showed that SHP inhibits DNA binding of STAT3 on the Socs3 gene promoter via interaction and colocalisation within the nucleus. Upregulation of inflammatory genes and downregulation of hepatic insulin signalling by acute IL-6 treatment were observed in wild-type mice but not in Shp null mice. Finally, chronic IL-6 exposure caused hepatic insulin resistance, leading to impaired insulin tolerance and elevated gluconeogenesis, and these phenomena were aggravated in Shp null mice. CONCLUSIONS/INTERPRETATION Our results demonstrate that SHP upregulation by metformin may prevent hepatic disorders by regulating the IL-6-dependent pathway, and that this pathway can help to ameliorate the pathogenesis of cytokine-mediated metabolic dysfunction.
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Affiliation(s)
- Y D Kim
- National Creative Research Initiatives Center for Nuclear Receptor Signals, Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Republic of Korea
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Whiley PAF, Miyamoto Y, McLachlan RI, Jans DA, Loveland KL. Changing subcellular localization of nuclear transport factors during human spermatogenesis. INTERNATIONAL JOURNAL OF ANDROLOGY 2012; 35:158-69. [PMID: 21812786 DOI: 10.1111/j.1365-2605.2011.01202.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Spermatogenesis requires progressive changes in gene expression mediated by hormonal and local factors. Regulated macromolecular movement between nuclear and cytoplasmic compartments enables these essential responses to changing extracellular cues, and dynamic production of the nucleocytoplasmic transporters and importin proteins, throughout gametogenesis in rodents implicates them as key mediators of germline differentiation. We examined normal adult human testis expression profiles of six importins plus five additional proteins involved in nucleocytoplasmic transport. Although most were detected in the nucleus during germline differentiation, importin α4 was exclusively observed in Sertoli and germ cell cytoplasm. Many proteins were present in round spermatid nuclei (importins α1, α3, β1, β3; exportin-1, Nup62, Ran, RanBP1, RCC1), and remarkable intense nuclear and/or nuclear-associated signals were detected for importin α1, importin α3 and Nup62 in spermatocytes. This study identifies conserved aspects of nucleocytoplasmic transport during spermatogenesis and extends our knowledge of the dynamic presence of these proteins, which indicates that they contribute to germ cell-specific cargo trafficking and potentially to other functions during human spermatogenesis. We also demonstrate for the first time that importin α3 is nuclear in spermatocytes, when exportin-1 is cytoplasmic, suggesting that nuclear transport is altered during meiosis.
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Affiliation(s)
- P A F Whiley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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Prinsloo E, Kramer AH, Edkins AL, Blatch GL. STAT3 interacts directly with Hsp90. IUBMB Life 2012; 64:266-73. [PMID: 22271514 DOI: 10.1002/iub.607] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 11/28/2011] [Indexed: 01/15/2023]
Abstract
Heat shock protein 90 (Hsp90) functionally modulates signal transduction. The signal transducer and activator of transcription 3 (STAT3) mediates interleukin-6 family cytokine signaling. Aberrant activation and mutation of STAT3 is associated with oncogenesis and immune disorders, respectively. Hsp90 and STAT3 have previously been shown to colocalize and coimmunoprecipitate in common complexes. Surface plasmon resonance spectroscopy revealed a direct, high affinity specific interaction between recombinant Hsp90β and STAT3β in the presence and absence of adenosine triphosphate (ATP) in molar excess. Furthermore, comparative analysis using a phosphomimetic mutation at tyrosine 705 showed that the direct interaction appeared to favor neither unactivated nor activated STAT3. Destabilizing mutation of STAT3 at arginine residues 414/417 to alanine in the DNA-binding domain, previously shown to disrupt nuclear translocation in vivo, reduced interaction with a STAT3 DNA binding site oligonucleotide and Hsp90β in vitro, indicating that STAT3 requires a functional DNA-binding domain for full direct interaction with Hsp90. Site-directed mutagenesis of a mammalian STAT3-EGFP-N1 fusion construct at RR414/417 and subsequent transfection into human MCF7 epithelial breast cancer cells showed no impaired nuclear translocation when observed by confocal laser scanning microscopy. However, costaining for Hsp90α/β isoforms and colocalization analysis revealed a defined decrease in pixel-on-pixel colocalization compared with the wild-type confirming the requirement of the DNA-binding domain for high-affinity interaction.
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Affiliation(s)
- Earl Prinsloo
- Biomedical Biotechnology Research Unit, Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, South Africa.
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Sonnino S, Prioni S, Chigorno V, Prinetti A. Interactions Between Caveolin-1 and Sphingolipids, and Their Functional Relevance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 749:97-115. [DOI: 10.1007/978-1-4614-3381-1_8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
Earlier electron microscopic data had shown that a hallmark of the vascular remodeling in pulmonary arterial hypertension (PAH) in man and experimental models includes enlarged vacuolated endothelial and smooth muscle cells with increased endoplasmic reticulum and Golgi stacks in pulmonary arterial lesions. In cell culture and in vivo experiments in the monocrotaline model, we observed disruption of Golgi function and intracellular trafficking with trapping of diverse vesicle tethers, SNAREs and SNAPs in the Golgi membranes of enlarged pulmonary arterial endothelial cells (PAECs) and pulmonary arterial smooth muscle cells (PASMCs). Consequences included the loss of cell surface caveolin-1, hyperactivation of STAT3, mislocalization of eNOS with reduced cell surface/caveolar NO and hypo-S-nitrosylation of trafficking-relevant proteins. Similar Golgi tether, SNARE and SNAP dysfunctions were also observed in hypoxic PAECs in culture and in PAECs subjected to NO scavenging. Strikingly, a hypo-NO state promoted PAEC mitosis and cell proliferation. Golgi dysfunction was also observed in pulmonary vascular cells in idiopathic PAH (IPAH) in terms of a marked cytoplasmic dispersal and increased cellular content of the Golgi tethers, giantin and p115, in cells in the proliferative, obliterative and plexiform lesions in IPAH. The question of whether there might be a causal relationship between trafficking dysfunction and vasculopathies of PAH was approached by genetic means using HIV-nef, a protein that disrupts endocytic and trans-Golgi trafficking. Macaques infected with a chimeric simian immunodeficiency virus (SIV) containing the HIV-nef gene (SHIV-nef), but not the non-chimeric SIV virus containing the endogenous SIV-nef gene, displayed pulmonary arterial vasculopathies similar to those in human IPAH. Only macaques infected with chimeric SHIV-nef showed pulmonary vascular lesions containing cells with dramatic cytoplasmic dispersal and increase in giantin and p115. Specifically, it was the HIV-nef–positive cells that showed increased giantin. Elucidating how each of these changes fits into the multifactorial context of hypoxia, reduced NO bioavailability, mutations in BMPR II, modulation of disease penetrance and gender effects in disease occurrence in the pathogenesis of PAH is part of the road ahead.
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Affiliation(s)
- Pravin B Sehgal
- Departments of Cell Biology & Anatomy, New York Medical College, Valhalla, New York, USA
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de Almeida CJ, Witkiewicz AK, Jasmin JF, Tanowitz HB, Sotgia F, Frank PG, Lisanti MP. Caveolin-2-deficient mice show increased sensitivity to endotoxemia. Cell Cycle 2011; 10:2151-61. [PMID: 21670588 DOI: 10.4161/cc.10.13.16234] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Caveolin proteins are structural components of caveolae and are involved in the regulation of many biological processes. Recent studies have shown that caveolin-1 modulates inflammatory responses and is important for sepsis development. In the present study, we show that caveolin-1 and caveolin-2 have opposite roles in lipopolysaccharide (LPS)-induced sepsis using caveolin-deficient (Cav-1 (-/-) and Cav-2 (-/-) ) mice for each of these proteins. While Cav-1 (-/-) mice displayed delayed mortality following challenge with LPS, Cav-2 (-/-) mice were more sensitive to LPS compared to wild-type (WT). With Cav-2 (-/-) mice, this effect was associated with increased intestinal injury and increased intestinal permeability. This negative outcome was also correlated with enhanced expression of iNOS in epithelial intestinal cells, and enhanced production of nitric oxide (NO). By contrast, Cav-1 (-/-) mice demonstrated a decrease in iNOS expression with decreased NO production, but no alteration in intestinal permeability. The differential expression of iNOS was associated with a significant increase of STAT-1 activation in these mice. Intestinal cells of Cav-2 (-/-) mice showed increased phosphorylation of STAT-1 at tyrosine 701 compared to wild-type. However, Cav-1 (-/-) mice-derived intestinal cells showed decreased levels of phosphorylation of STAT-1 at tyrosine 701. Since caveolin-2 is almost completely absent in Cav-1 (-/-) mice, we conclude that it is not just the absence of caveolin-2 that is responsible for the observed effects, but that the balance between caveolin-1 and caveolin-2 is important for iNOS expression and ultimately for sepsis outcome.
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Affiliation(s)
- Cecilia J de Almeida
- Department of Cancer Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
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Serrano-Marco L, Rodríguez-Calvo R, El Kochairi I, Palomer X, Michalik L, Wahli W, Vázquez-Carrera M. Activation of peroxisome proliferator-activated receptor-β/-δ (PPAR-β/-δ) ameliorates insulin signaling and reduces SOCS3 levels by inhibiting STAT3 in interleukin-6-stimulated adipocytes. Diabetes 2011; 60:1990-9. [PMID: 21617181 PMCID: PMC3121427 DOI: 10.2337/db10-0704] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE It has been suggested that interleukin (IL)-6 is one of the mediators linking obesity-derived chronic inflammation with insulin resistance through activation of STAT3, with subsequent upregulation of suppressor of cytokine signaling 3 (SOCS3). We evaluated whether peroxisome proliferator-activated receptor (PPAR)-β/-δ prevented activation of the IL-6-STAT3-SOCS3 pathway and insulin resistance in adipocytes. RESEARCH DESIGN AND METHODS Adipocytes and white adipose tissue from wild-type and PPAR-β/-δ-null mice were used to evaluate the effect of PPAR-β/-δ on the IL-6-STAT3-SOCS3 pathway. RESULTS First, we observed that the PPAR-β/-δ agonist GW501516 prevented both IL-6-dependent reduction in insulin-stimulated Akt phosphorylation and glucose uptake in adipocytes. In addition, this drug treatment abolished IL-6-induced SOCS3 expression in differentiated 3T3-L1 adipocytes. This effect was associated with the capacity of the drug to prevent IL-6-induced STAT3 phosphorylation on Tyr(705) and Ser(727) residues in vitro and in vivo. Moreover, GW501516 prevented IL-6-dependent induction of extracellular signal-related kinase (ERK)1/2, a serine-threonine-protein kinase involved in serine STAT3 phosphorylation. Furthermore, in white adipose tissue from PPAR-β/-δ-null mice, STAT3 phosphorylation (Tyr(705) and Ser(727)), STAT3 DNA-binding activity, and SOCS3 protein levels were higher than in wild-type mice. Several steps in STAT3 activation require its association with heat shock protein 90 (Hsp90), which was prevented by GW501516 as revealed in immunoprecipitation studies. Consistent with this finding, the STAT3-Hsp90 association was enhanced in white adipose tissue from PPAR-β/-δ-null mice compared with wild-type mice. CONCLUSIONS Collectively, our findings indicate that PPAR-β/-δ activation prevents IL-6-induced STAT3 activation by inhibiting ERK1/2 and preventing the STAT3-Hsp90 association, an effect that may contribute to the prevention of cytokine-induced insulin resistance in adipocytes.
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Affiliation(s)
- Lucía Serrano-Marco
- Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, University of Barcelona, Institut de Biomedicina de la UB (IBUB), and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain
| | - Ricardo Rodríguez-Calvo
- Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, University of Barcelona, Institut de Biomedicina de la UB (IBUB), and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain
| | - Ilhem El Kochairi
- Center for Integrative Genomics, National Research Center Frontiers in Genetics, University of Lausanne, Lausanne, Switzerland
| | - Xavier Palomer
- Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, University of Barcelona, Institut de Biomedicina de la UB (IBUB), and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain
| | - Liliane Michalik
- Center for Integrative Genomics, National Research Center Frontiers in Genetics, University of Lausanne, Lausanne, Switzerland
| | - Walter Wahli
- Center for Integrative Genomics, National Research Center Frontiers in Genetics, University of Lausanne, Lausanne, Switzerland
| | - Manuel Vázquez-Carrera
- Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, University of Barcelona, Institut de Biomedicina de la UB (IBUB), and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain
- Corresponding author: Manuel Vázquez-Carrera,
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Guo CJ, Yang XB, Wu YY, Yang LS, Mi S, Liu ZY, Jia KT, Huang YX, Weng SP, Yu XQ, He JG. Involvement of caveolin-1 in the Jak-Stat signaling pathway and infectious spleen and kidney necrosis virus infection in mandarin fish (Siniperca chuatsi). Mol Immunol 2011; 48:992-1000. [PMID: 21296425 PMCID: PMC7112660 DOI: 10.1016/j.molimm.2011.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 12/01/2010] [Accepted: 01/01/2011] [Indexed: 12/21/2022]
Abstract
Caveolae, the major source of caveolin-1 protein, are specialized invaginated microdomains of the plasma membrane that act as organizing centers for signaling molecules in the immune system. In the present study, we report the cloning and characterization of caveolin-1 (mCav-1) from mandarin fish (Siniperca chuatsi) and study on the roles of mCav-1 in the fish Jak–Stat signaling pathway and in virus infection. The cDNA sequence of mCav-1 was 707 bp in size, encoding a protein of 181 amino acids, which was different from the mammalian protein (178 amino acids). The deduced amino acid sequence of mCav-1 shared similar architecture with vertebrate caveolin-1 proteins, but mCav-1 lacked a phosphorylation site (y14). The major subcellular location of mCav-1 was in the caveolae, where the protein appeared to have major functions. Real-time PCR revealed that the expression of the mandarin fish Mx, IRF-1, SOCS1, and SOCS3 genes involved in the poly(I:C)-induced Jak–Stat signaling pathway was impaired by the mCav-1 scaffolding domain peptide (mSDP). In mandarin fish fry (MFF-1) cells, the protein levels of mCav-1 were markedly up-regulated at 12 and 24 h post-infection with ISKNV (infectious spleen and kidney necrosis virus). In addition, ISKNV entry into MFF-1 cells was significantly inhibited by mSDP, and the inhibition was dose-dependent. Thus, ISKNV infection was apparently associated with mCav-1 protein and may utilize the caveolae-related endocytosis pathway. The findings reported here further our understanding of the function of caveolin-1 in the complex signal transduction network in fish immune systems and in the cellular entry mechanism of iridoviruses.
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Affiliation(s)
- Chang-Jun Guo
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Marine Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
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Jawa RS, Anillo S, Huntoon K, Baumann H, Kulaylat M. Analytic review: Interleukin-6 in surgery, trauma, and critical care: part I: basic science. J Intensive Care Med 2011; 26:3-12. [PMID: 21262749 PMCID: PMC6209321 DOI: 10.1177/0885066610395678] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A variety of cytokines play a role in the response to an inflammatory stimulus. The interleukin-6 (IL-6)-type cytokines are released in response to tissue injury or an inflammatory stimulus. They act locally and systemically to generate a variety of physiologic responses, principal among them is the acute phase response. The IL-6 type cytokines demonstrate pleiotropy and redundancy of actions. This is made possible by the distinctive characteristics of the IL-6 receptor complex, which contains an ubiquitous subunit that is shared by most IL-6-type cytokines, as well as a cytokine-specific subunit.
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Affiliation(s)
- Randeep S Jawa
- Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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Rao W, Isaac RE, Keen JN. An analysis of the Caenorhabditis elegans lipid raft proteome using geLC-MS/MS. J Proteomics 2010; 74:242-53. [PMID: 21070894 DOI: 10.1016/j.jprot.2010.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 10/20/2010] [Accepted: 11/02/2010] [Indexed: 11/16/2022]
Abstract
Lipid rafts are microdomains of the phospholipid bilayer, proposed to form semi-stable "islands" that act as a platform for several important cellular processes; major classes of raft-resident proteins include signalling proteins and glycosylphosphatidylinositol (GPI)-anchored proteins. Proteomic studies into lipid rafts have been mainly carried out in mammalian cell lines and single cell organisms. The nematode Caenorhabditis elegans, the model organism with a well-defined developmental profile, is ideally suited for the study of this subcellular locale in a complex developmental context. A study of the lipid raft proteome of C. elegans is presented here. A total of 44 proteins were identified from the lipid raft fraction using geLC-MS/MS, of which 40 have been determined to be likely raft proteins after analysis of predicted functions. Prediction of GPI-anchoring of the proteins found 21 to be potentially modified in this way, two of which were experimentally confirmed to be GPI-anchored. This work is the first reported study of the lipid raft proteome in C. elegans. The results show that raft proteins, including numerous GPI-anchored proteins, may have a variety of potentially important roles within the nematode, and will hopefully lead to C. elegans becoming a useful model for the study of lipid rafts.
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Affiliation(s)
- Wei Rao
- Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
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Howard M, Roux J, Lee H, Miyazawa B, Lee JW, Gartland B, Howard AJ, Matthay MA, Carles M, Pittet JF. Activation of the stress protein response inhibits the STAT1 signalling pathway and iNOS function in alveolar macrophages: role of Hsp90 and Hsp70. Thorax 2010; 65:346-53. [PMID: 20388761 DOI: 10.1136/thx.2008.101139] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND AIM Alveolar fluid clearance is impaired by inducible nitric oxide synthase (iNOS)/nitric oxide (NO)-dependent mechanisms in acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). The activation of the stress protein response (SPR) in alveolar macrophages on iNOS-dependent NO production in response to interferon gamma (IFNgamma), a major cytokine present in the airspace of patients with ALI, was investigated. METHODS The SPR was activated in murine and primary human alveolar macrophages prior to analysis of signal transducer and activator of transcription factor 1 (STAT1) activation, iNOS mRNA and protein synthesis, and NO production. RESULTS SPR activation resulted in inhibition of IFNgamma-mediated NO production (p=0.001) with >95% detergent insolubilisation of the STAT1 protein. Its subsequent proteasomal degradation was partially reversed with pretreatment of cells with the chemical chaperone glycerol. This early effect of the SPR was caused by the complete disruption of heat shock protein 90 (Hsp90)-STAT1 binding, as shown by immunoprecipitation. Recovery of STAT1 activation and recovery of iNOS synthesis occurred within 12 h after SPR activation (p=0.02). NO production (as compared with non-SPR controls) did not occur until 48 h later (p=0.02). SPR-induced Hsp70 (Hsp70i) expression caused a late inhibition of NO production (p=0.02). Inhibiting >50% Hsp70i expression recovered NO production to control levels whereas overexpressing Hsp70i in the absence of the SPR inhibited NO production (p=0.02). CONCLUSION Early inhibition of STAT1 following its dissociation from Hsp90, and later inhibition of iNOS activity by Hsp70i, represent novel mechanisms by which SPR activation modulates the IFNgamma signalling in alveolar macrophages. These results highlight a potential clinical application for Hsp90 inhibitors in modulating NO signalling during the early phase of acute lung injury.
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Affiliation(s)
- Marybeth Howard
- Laboratory of Surgical Research, Department of Anesthesia, University of California, San Francisco, CA 94110, USA.
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Kim KS, Yoon YR, Lee HJ, Yoon S, Kim SY, Shin SW, An JJ, Kim MS, Choi SY, Sun W, Baik JH. Enhanced hypothalamic leptin signaling in mice lacking dopamine D2 receptors. J Biol Chem 2010; 285:8905-17. [PMID: 20080963 DOI: 10.1074/jbc.m109.079590] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The dopamine D(2) receptor (D2R) plays a critical role in diverse neurophysiological functions. D2R knock-out mice (D2R(-/-)) show reduced food intake and body weight while displaying an increased basal energy expenditure level, compared with their wild type littermates. Thus, these mice show a lean phenotype. D2R(-/-) mice displayed increased leptin sensitivity, and leptin injection induced increased phosphorylation of the hypothalamic signal transducer and activator of transcription 3 (STAT3) in D2R(-/-) mice relative to wild type littermates. Using double immunofluorescence histochemistry, we have demonstrated that D2Rs are present in leptin-sensitive STAT3-positive cells in the arcuate nucleus of the hypothalamus and that leptin injection induces STAT3 phosphorylation in hypothalamic neurons expressing D2Rs. Stimulation of D2R by the D2R agonist quinpirole suppressed the leptin-induced STAT3 phosphorylation and nuclear trans-localization of phospho-STAT3 in the hypothalamus of wild type mice. However, this regulation was not detected in the D2R(-/-) mice. Treatment of D2R agonist and antagonist could modulate the leptin-induced food intake and body weight changes in wild type mice but not in D2R(-/-) mice. Together, our findings suggest that the interaction between the dopaminergic system and leptin signaling in hypothalamus is important in control of energy homeostasis.
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Affiliation(s)
- Kyu Seok Kim
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
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Prinsloo E, Setati MM, Longshaw VM, Blatch GL. Chaperoning stem cells: a role for heat shock proteins in the modulation of stem cell self-renewal and differentiation? Bioessays 2009; 31:370-7. [DOI: 10.1002/bies.200800158] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Sonnino S, Prinetti A. Sphingolipids and membrane environments for caveolin. FEBS Lett 2009; 583:597-606. [DOI: 10.1016/j.febslet.2009.01.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 01/07/2009] [Accepted: 01/08/2009] [Indexed: 01/22/2023]
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Nixon B, Bielanowicz A, Mclaughlin EA, Tanphaichitr N, Ensslin MA, Aitken RJ. Composition and significance of detergent resistant membranes in mouse spermatozoa. J Cell Physiol 2009; 218:122-34. [DOI: 10.1002/jcp.21575] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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50
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Maruvada R, Argon Y, Prasadarao NV. Escherichia coli interaction with human brain microvascular endothelial cells induces signal transducer and activator of transcription 3 association with the C-terminal domain of Ec-gp96, the outer membrane protein A receptor for invasion. Cell Microbiol 2008; 10:2326-38. [PMID: 18662321 PMCID: PMC2579944 DOI: 10.1111/j.1462-5822.2008.01214.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Our inability to develop new therapeutic strategies to prevent meningitis due to Escherichia coli K1 is attributed to our incomplete understanding of the pathophysiology of the disease. Previously, we demonstrated that outer membrane protein A of E. coli interacts with a gp96 homologue, Ec-gp96, on human brain microvascular endothelial cells (HBMEC) for invasion. However, signalling events mediated by Ec-gp96 that allow internalization of E. coli are incompletely understood. Here, we demonstrate that signal transducer and activator of transcription 3 (Stat3) activation and its interaction with Ec-gp96 were critical for E. coli invasion. The activated Stat3 was colocalized with Ec-gp96 at the actin condensation sites, and overexpressing a dominant negative (DN) form of Stat3 in HBMEC significantly abrogated the invasion. Furthermore, overexpression of Ec-gp96Delta200, the C-terminal 214-amino-acid truncated Ec-gp96, prevented the invasion of E. coli in HBMEC. In contrast, lack of ATP binding by gp96 did not affect the invasion. Overexpression of DN forms of either phosphatidyl inositol-3 kinase (PI3-kinase) subunit p85 or protein kinase C-alpha (PKC-alpha) had no effect on the activation of Stat3 and its association with Ec-gp96, whereas overexpression of DN-Stat3 abolished the activation of both PI3-kinase and PKC-alpha. Together, our findings identified a novel interaction of Stat3 with Ec-gp96, upstream of PI3-kinase and PKC-alpha activation that is required for the invasion of E. coli into HBMEC.
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Affiliation(s)
- Ravi Maruvada
- Division of Infectious Diseases, The Saban Research Institute, Childrens Hospital Los Angeles
| | - Yair Argon
- Division of Cell Pathology, Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nemani V. Prasadarao
- Division of Infectious Diseases, The Saban Research Institute, Childrens Hospital Los Angeles
- Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA
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