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Young FB, Franciosi S, Spreeuw A, Deng Y, Sanders S, Tam NCM, Huang K, Singaraja RR, Zhang W, Bissada N, Kay C, Hayden MR. Low levels of human HIP14 are sufficient to rescue neuropathological, behavioural, and enzymatic defects due to loss of murine HIP14 in Hip14-/- mice. PLoS One 2012; 7:e36315. [PMID: 22649491 PMCID: PMC3359340 DOI: 10.1371/journal.pone.0036315] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 04/02/2012] [Indexed: 11/25/2022] Open
Abstract
Huntingtin Interacting Protein 14 (HIP14) is a palmitoyl acyl transferase (PAT) that was first identified due to altered interaction with mutant huntingtin, the protein responsible for Huntington Disease (HD). HIP14 palmitoylates a specific set of neuronal substrates critical at the synapse, and downregulation of HIP14 by siRNA in vitro results in increased cell death in neurons. We previously reported that mice lacking murine Hip14 (Hip14-/-) share features of HD. In the current study, we have generated human HIP14 BAC transgenic mice and crossed them to the Hip14-/- model in order to confirm that the defects seen in Hip14-/- mice are in fact due to loss of Hip14. In addition, we sought to determine whether human HIP14 can provide functional compensation for loss of murine Hip14. We demonstrate that despite a relative low level of expression, as assessed via Western blot, BAC-derived human HIP14 compensates for deficits in neuropathology, behavior, and PAT enzyme function seen in the Hip14-/- model. Our findings yield important insights into HIP14 function in vivo.
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Affiliation(s)
- Fiona B. Young
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sonia Franciosi
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amanda Spreeuw
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yu Deng
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shaun Sanders
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Natalie C. M. Tam
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kun Huang
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Roshni R. Singaraja
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Weining Zhang
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nagat Bissada
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chris Kay
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael R. Hayden
- Department of Medical Genetics and Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
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2
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Uribe V, Wong BK, Graham RK, Cusack CL, Skotte NH, Pouladi MA, Xie Y, Feinberg K, Ou Y, Ouyang Y, Deng Y, Franciosi S, Bissada N, Spreeuw A, Zhang W, Ehrnhoefer DE, Vaid K, Miller FD, Deshmukh M, Howland D, Hayden MR. Rescue from excitotoxicity and axonal degeneration accompanied by age-dependent behavioral and neuroanatomical alterations in caspase-6-deficient mice. Hum Mol Genet 2012; 21:1954-67. [PMID: 22262731 PMCID: PMC3315204 DOI: 10.1093/hmg/dds005] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 01/09/2012] [Indexed: 11/13/2022] Open
Abstract
Apoptosis, or programmed cell death, is a cellular pathway involved in normal cell turnover, developmental tissue remodeling, embryonic development, cellular homeostasis maintenance and chemical-induced cell death. Caspases are a family of intracellular proteases that play a key role in apoptosis. Aberrant activation of caspases has been implicated in human diseases. In particular, numerous findings implicate Caspase-6 (Casp6) in neurodegenerative diseases, including Alzheimer disease (AD) and Huntington disease (HD), highlighting the need for a deeper understanding of Casp6 biology and its role in brain development. The use of targeted caspase-deficient mice has been instrumental for studying the involvement of caspases in apoptosis. The goal of this study was to perform an in-depth neuroanatomical and behavioral characterization of constitutive Casp6-deficient (Casp6-/-) mice in order to understand the physiological function of Casp6 in brain development, structure and function. We demonstrate that Casp6-/- neurons are protected against excitotoxicity, nerve growth factor deprivation and myelin-induced axonal degeneration. Furthermore, Casp6-deficient mice show an age-dependent increase in cortical and striatal volume. In addition, these mice show a hypoactive phenotype and display learning deficits. The age-dependent behavioral and region-specific neuroanatomical changes observed in the Casp6-/- mice suggest that Casp6 deficiency has a more pronounced effect in brain regions that are involved in neurodegenerative diseases, such as the striatum in HD and the cortex in AD.
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Affiliation(s)
- Valeria Uribe
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Bibiana K.Y. Wong
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Rona K. Graham
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Corey L. Cusack
- Department of Cell and Developmental Biology and Neuroscience Center, University of North Carolina, Chapel Hill, NC27599-7250, USA
| | - Niels H. Skotte
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
- Department of Medical Genetics, Institute of Cellular and Molecular Medicine, University of Copenhagen, 2200 N Copenhagen, Denmark
| | - Mahmoud A. Pouladi
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Yuanyun Xie
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Konstantin Feinberg
- Developmental and Stem Cell Biology Group, Hospital for Sick Children, Toronto, OntarioM5G1L7, Canada
| | - Yimiao Ou
- Developmental and Stem Cell Biology Group, Hospital for Sick Children, Toronto, OntarioM5G1L7, Canada
| | | | - Yu Deng
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Sonia Franciosi
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Nagat Bissada
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Amanda Spreeuw
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Weining Zhang
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Dagmar E. Ehrnhoefer
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Kuljeet Vaid
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Freda D. Miller
- Developmental and Stem Cell Biology Group, Hospital for Sick Children, Toronto, OntarioM5G1L7, Canada
- Department of Molecular Genetics and
- Department of Physiology, University of Toronto, Toronto, OntarioM5G1X5, Canada
| | - Mohanish Deshmukh
- Department of Cell and Developmental Biology and Neuroscience Center, University of North Carolina, Chapel Hill, NC27599-7250, USA
| | | | - Michael R. Hayden
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
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3
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Graham RK, Deng Y, Pouladi MA, Vaid K, Ehrnhoefer D, Southwell AL, Bissada N, Franciosi S, Hayden MR. Caspase-6-Resistant Mutant Huntingtin Does not Rescue the Toxic Effects of Caspase-Cleavable Mutant Huntingtin in vivo. J Huntingtons Dis 2012; 1:243-60. [DOI: 10.3233/jhd-120038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Rona K. Graham
- Research Center on Aging, Department of Physiology and Biophysics, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Yu Deng
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Mahmoud A. Pouladi
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore, Republic of Singapore
- Department of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Kuljeet Vaid
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Dagmar Ehrnhoefer
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Amber L. Southwell
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Nagat Bissada
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Sonia Franciosi
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
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Singaraja RR, Huang K, Sanders SS, Milnerwood AJ, Hines R, Lerch JP, Franciosi S, Drisdel RC, Vaid K, Young FB, Doty C, Wan J, Bissada N, Henkelman RM, Green WN, Davis NG, Raymond LA, Hayden MR. Altered palmitoylation and neuropathological deficits in mice lacking HIP14. Hum Mol Genet 2011; 20:3899-909. [PMID: 21775500 PMCID: PMC3177655 DOI: 10.1093/hmg/ddr308] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 07/02/2011] [Accepted: 07/11/2011] [Indexed: 02/02/2023] Open
Abstract
Huntingtin interacting protein 14 (HIP14, ZDHHC17) is a huntingtin (HTT) interacting protein with palmitoyl transferase activity. In order to interrogate the function of Hip14, we generated mice with disruption in their Hip14 gene. Hip14-/- mice displayed behavioral, biochemical and neuropathological defects that are reminiscent of Huntington disease (HD). Palmitoylation of other HIP14 substrates, but not Htt, was reduced in the Hip14-/- mice. Hip14 is dysfunctional in the presence of mutant htt in the YAC128 mouse model of HD, suggesting that altered palmitoylation mediated by HIP14 may contribute to HD.
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Affiliation(s)
- Roshni R. Singaraja
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - Kun Huang
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - Shaun S. Sanders
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | | | - Rochelle Hines
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Jason P. Lerch
- The Mouse Imaging Centre, The Hospital for Sick Children, Toronto, ON, Canada
| | - Sonia Franciosi
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | | | - Kuljeet Vaid
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - Fiona B. Young
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - Crystal Doty
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - Junmei Wan
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Nagat Bissada
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
| | - R. Mark Henkelman
- The Mouse Imaging Centre, The Hospital for Sick Children, Toronto, ON, Canada
| | - William N. Green
- Department of Neurobiology, University of Chicago, Chicago, IL, USA and
| | - Nicholas G. Davis
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Lynn A. Raymond
- Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics and Child and Family Research Institute and
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5
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Carroll JB, Lerch JP, Franciosi S, Spreeuw A, Bissada N, Henkelman RM, Hayden MR. Natural history of disease in the YAC128 mouse reveals a discrete signature of pathology in Huntington disease. Neurobiol Dis 2011; 43:257-65. [DOI: 10.1016/j.nbd.2011.03.018] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 03/07/2011] [Accepted: 03/23/2011] [Indexed: 11/25/2022] Open
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6
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Heshmat S, Moore PC, Kamel M, Moussa O, Bissada N. Effect of genitourinary cancer mortality calculated using the potential years of life lost (PYLL): Trends from 1972-2006 based on a report from the Surveillance, Epidemiology, and End Results (SEER) database. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.7_suppl.350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
350 Background: We aim to illustrate the potential years of life lost (PYLL) and the average years of life lost (AYLL); secondary to genitourinary cancer in US during the period from 1972-2006 utilizing the Surveillance, Epidemiology and End Results (SEER) database, and illustrate the trends in the PYLL over this time period. Methods: PYLL were calculated to assess premature mortality trends in US for ureter, urinary bladder, kidney and renal pelvis, penis, testis, and prostate cancers. AYLL is the average of the differences between the actual ages at death and the expected remaining years of life for each person who died of cancer. Calculations were made based on the SEER cancer mortality data. Results: There were a total of 7,733,235 PYLL in both men and women secondary to urogenital cancer in US in the period from 1972-2006. In both males and females, the greatest PYLL were for kidney and renal pelvis cancer related mortality. In both sexes no improvement in PYLL secondary to ureteral and bladder cancer related mortality was observed. In males the greatest reduction in PYLL was in testicular cancer followed by prostate cancer. Conclusions: PYLL and AYLL are two powerful tools that reflect the impact of cancer related mortality on society. There has been an increasing trend in PYLL related to urogenital cancers over the last 35 years for both males and females. Kidney cancer had the highest increase in PYLL among both genders and more efforts are needed to address its progression. No significant financial relationships to disclose.
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Affiliation(s)
- S. Heshmat
- University of Arkansas for Medical Sciences, Little Rock, AR; University of South Carolina, Columbia, SC
| | - P. C. Moore
- University of Arkansas for Medical Sciences, Little Rock, AR; University of South Carolina, Columbia, SC
| | - M. Kamel
- University of Arkansas for Medical Sciences, Little Rock, AR; University of South Carolina, Columbia, SC
| | - O. Moussa
- University of Arkansas for Medical Sciences, Little Rock, AR; University of South Carolina, Columbia, SC
| | - N. Bissada
- University of Arkansas for Medical Sciences, Little Rock, AR; University of South Carolina, Columbia, SC
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7
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Graham RK, Deng Y, Pouladi MA, Vaid K, Xie Y, Bissada N, Franciosi S, Hayden MR. A04 Caspase 6 resistant mutant huntingtin does not rescue the toxic effects of caspase cleavable mutant huntingtin in vivo. J Neurol Neurosurg Psychiatry 2010. [DOI: 10.1136/jnnp.2010.222570.4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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8
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Pouladi MA, Xie Y, Skotte NH, Ehrnhoefer DE, Graham RK, Kim JE, Bissada N, Yang XW, Paganetti P, Friedlander RM, Leavitt BR, Hayden MR. Full-length huntingtin levels modulate body weight by influencing insulin-like growth factor 1 expression. Hum Mol Genet 2010; 19:1528-38. [PMID: 20097678 DOI: 10.1093/hmg/ddq026] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Levels of full-length huntingtin (FL htt) influence organ and body weight, independent of polyglutamine length. The growth hormone-insulin like growth factor-1 (GH-IGF-1) axis is well established as a regulator of organ growth and body weight. In this study, we investigate the involvement of the IGF-1 pathway in mediating the effect of htt on body weight. IGF-1 expression was examined in transgenic mouse lines expressing different levels of FL wild-type (WT) htt (YAC18 mice), FL mutant htt (YAC128 and BACHD mice) and truncated mutant htt (shortstop mice). We demonstrate that htt influences body weight by modulating the IGF-1 pathway. Plasma IGF-1 levels correlate with body weight and htt levels in the transgenic YAC mice expressing human htt. The effect of htt on IGF-1 expression is independent of CAG size. No effect on body weight is observed in transgenic YAC mice expressing a truncated N-terminal htt fragment (shortstop), indicating that FL htt is required for the modulation of IGF-1 expression. Treatment with 17beta-estradiol (17beta-ED) lowers the levels of circulating IGF-1 in mammals. Treatment of YAC128 with 17beta-ED, but not placebo, reduces plasma IGF-1 levels and decreases the body weight of YAC128 animals to WT levels. Furthermore, given the ubiquitous expression of IGF-1 within the central nervous system, we also examined the impact of FL htt levels on IGF-1 expression in different regions of the brain, including the striatum, cerebellum of YAC18, YAC128 and littermate WT mice. We demonstrate that the levels of FL htt influence IGF-1 expression in striatal tissues. Our data identify a novel function for FL htt in influencing IGF-1 expression.
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Affiliation(s)
- Mahmoud A Pouladi
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, and Child and Family Research Institute, Vancouver, BC, Canada V5Z 4H4
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9
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Abdallah M, Badreldin M, Bissada N. UP-3.028: Issues and Challenges in Early Learning of Laparoscopic Radical Cystectomy: The Menoufia University Experience with 21 Patients. Urology 2009. [DOI: 10.1016/j.urology.2009.07.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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Safwat A, Bissada N, Kumar U, Greene G, Madi R, Miedema M. MP-08.09: Laparoscopic Partial Nephrectomy Versus Laparoscopic Renal Cryoablation: Comparison of Operative and Oncologic Outcome. Urology 2009. [DOI: 10.1016/j.urology.2009.07.959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Safwat A, Bissada N, Elgammal M, Abdalla M. POD-12.07: Urethral Ultrasound Versus Magnetic Resonance Urethrography Versus Retrograde Urethrography in the Evaluation of Anterior Urethral Stricture: A Prospective Study. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Safwat A, Bissada N, Kumar U, Madi R, Miedema M. POD-06.08: Transperitoneal Versus Retroperitoneal Laparoscopic Radical Nephrectomy: Comparison of Operative and Postoperative Course and Outcome. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Macdonald MLE, Bissada N, Vallance BA, Hayden MR. Absence of stearoyl-CoA desaturase-1 does not promote DSS-induced acute colitis. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:1166-72. [PMID: 19695343 DOI: 10.1016/j.bbalip.2009.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 07/24/2009] [Accepted: 08/07/2009] [Indexed: 01/30/2023]
Abstract
Absence of stearoyl-CoA desaturase-1 (SCD1) in mice leads to chronic inflammation of the skin and increased susceptibility to atherosclerosis, while also increasing plasma inflammatory markers. A recent report suggested that SCD1 deficiency also increases disease severity in a mouse model of inflammatory bowel disease, induced by dextran sulfate sodium (DSS). However, SCD1-deficient mice are known to consume increased amounts of water, which would also be expected to increase the intake of DSS-treated water. The aim of this study was to determine the effect of SCD1 deficiency on DSS-induced acute colitis with DSS dosing adjusted to account for genotype differences in fluid consumption. Wild-type controls were treated with 3.5% DSS for 5 days to induce moderately severe colitis, while the concentration of DSS given to SCD1-deficient mice was lowered to 2.5% to control for increased fluid consumption. Colonic inflammation was assessed by clinical and histological scoring. Although SCD1-deficient mice consumed a total intake of DSS that was greater than that of wild-type controls, colonic inflammation, colon length and fecal blood were not altered by SCD1-deficiency in DSS-induced colitis, while diarrhea and total weight loss were modestly improved. Despite SCD1 deficiency leading to chronic inflammation of the skin and increased susceptibility to atherosclerosis, it does not accelerate inflammation in the DSS-induced model of acute colitis when DSS intake is controlled. These observations suggest that SCD1 deficiency does not play a significant role in colonic inflammation in this model.
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Affiliation(s)
- Marcia L E Macdonald
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, BC, Canada V5Z 4H4
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14
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Brunham LR, Singaraja RR, Duong M, Timmins JM, Fievet C, Bissada N, Kang MH, Samra A, Fruchart JC, McManus B, Staels B, Parks JS, Hayden MR. Tissue-specific roles of ABCA1 influence susceptibility to atherosclerosis. Arterioscler Thromb Vasc Biol 2009; 29:548-54. [PMID: 19201688 DOI: 10.1161/atvbaha.108.182303] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The ATP-binding cassette transporter, subfamily A, member 1 (ABCA1) plays a key role in HDL cholesterol metabolism. However, the role of ABCA1 in modulating susceptibility to atherosclerosis is controversial. METHODS AND RESULTS We investigated the role of ABCA1 in atherosclerosis using a combination of overexpression and selective deletion models. First, we examined the effect of transgenic overexpression of a full-length human ABCA1-containing bacterial artificial chromosome (BAC) in the presence or absence of the endogenous mouse Abca1 gene. ABCA1 overexpression in the atherosclerosis-susceptible Ldlr(-/-) background significantly reduced the development of atherosclerosis in both the presence and absence of mouse Abca1. Next, we used mice with tissue-specific inactivation of Abca1 to dissect the discrete roles of Abca1 in different tissues on susceptibility to atherosclerosis. On the Apoe(-/-) background, mice lacking hepatic Abca1 had significantly reduced HDL cholesterol and accelerated atherosclerosis, indicating that the liver is an important site at which Abca1 plays an antiatherogenic role. In contrast, mice with macrophage-specific inactivation of Abca1 on the Ldlr(-/-) background displayed no change in atherosclerotic lesion area. CONCLUSIONS These data indicate that physiological expression of Abca1 modulates the susceptibility to atherosclerosis and establish hepatic Abca1 expression as an important site of atheroprotection. In contrast, we show that selective deletion of macrophage Abca1 does not significantly modulate atherogenesis.
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Affiliation(s)
- Liam R Brunham
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada
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15
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MacDonald MLE, van Eck M, Hildebrand RB, Wong BWC, Bissada N, Ruddle P, Kontush A, Hussein H, Pouladi MA, Chapman MJ, Fievet C, van Berkel TJC, Staels B, McManus BM, Hayden MR. Despite antiatherogenic metabolic characteristics, SCD1-deficient mice have increased inflammation and atherosclerosis. Arterioscler Thromb Vasc Biol 2008; 29:341-7. [PMID: 19095997 DOI: 10.1161/atvbaha.108.181099] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Absence of stearoyl-CoA desaturase-1 (SCD1) in mice reduces plasma triglycerides and provides protection from obesity and insulin resistance, which would be predicted to be associated with reduced susceptibility to atherosclerosis. The aim of this study was to determine the effect of SCD1 deficiency on atherosclerosis. METHODS AND RESULTS Despite an antiatherogenic metabolic profile, SCD1 deficiency increases atherosclerosis in hyperlipidemic low-density lipoprotein receptor (LDLR)-deficient mice challenged with a Western diet. Lesion area at the aortic root is significantly increased in males and females in two models of SCD1 deficiency. Inflammatory changes are evident in the skin of these mice, including increased intercellular adhesion molecule (ICAM)-1 and ulcerative dermatitis. Increases in ICAM-1 and interleukin-6 are also evident in plasma of SCD1-deficient mice. HDL particles demonstrate changes associated with inflammation, including decreased plasma apoA-II and apoA-I and paraoxonase-1 and increased plasma serum amyloid A. Lipopolysaccharide-induced inflammatory response and cholesterol efflux are not altered in SCD1-deficient macrophages. In addition, when SCD1 deficiency is limited to bone marrow-derived cells, lesion size is not altered in LDLR-deficient mice. CONCLUSIONS These studies reinforce the crucial role of chronic inflammation in promoting atherosclerosis, even in the presence of antiatherogenic biochemical and metabolic characteristics.
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Affiliation(s)
- Marcia L E MacDonald
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
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MacDonald MLE, Singaraja RR, Bissada N, Ruddle P, Watts R, Karasinska JM, Gibson WT, Fievet C, Vance JE, Staels B, Hayden MR. Absence of stearoyl-CoA desaturase-1 ameliorates features of the metabolic syndrome in LDLR-deficient mice. J Lipid Res 2007; 49:217-29. [PMID: 17960025 DOI: 10.1194/jlr.m700478-jlr200] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A combination of the interrelated metabolic risk factors obesity, insulin resistance, dyslipidemia, and hypertension, often described as the "metabolic syndrome," is known to increase the risk of developing cardiovascular disease and diabetes. Stearoyl-coenzyme A desaturase (SCD) activity has been implicated in the metabolic syndrome, but detailed studies of the beneficial metabolic effects of SCD deficiency have been limited. Here, we show that absence of the Scd1 gene product reduces plasma triglycerides and reduces weight gain in severely hyperlipidemic low density lipoprotein receptor (LDLR)-deficient mice challenged with a Western diet. Absence of SCD1 also increases insulin sensitivity, as measured by intraperitoneal glucose and insulin tolerance testing. SCD1 deficiency dramatically reduces hepatic lipid accumulation while causing more modest reductions in plasma apolipoproteins, suggesting that in conditions of sustained hyperlipidemia, SCD1 functions primarily to mediate lipid stores. In addition, absence of SCD1 partially ameliorates the undesirable hypertriglyceridemic effect of antiatherogenic liver X receptor agonists. Our results demonstrate that constitutive reduction of SCD activity improves the metabolic phenotype of LDLR-deficient mice on a Western diet.
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Affiliation(s)
- Marcia L E MacDonald
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
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17
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Metzler M, Gan L, Pan Wong T, Liu L, Helm J, Liu L, Georgiou J, Wang Y, Bissada N, Cheng K, Roder JC, Wang YT, Hayden MR. NMDA receptor function and NMDA receptor-dependent phosphorylation of huntingtin is altered by the endocytic protein HIP1. J Neurosci 2007; 27:2298-308. [PMID: 17329427 PMCID: PMC6673493 DOI: 10.1523/jneurosci.5175-06.2007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Huntingtin-interacting protein 1 (HIP1) is an endocytic adaptor protein that plays a role in clathrin-mediated endocytosis and the ligand-induced internalization of AMPA receptors (AMPARs) (Metzler et al., 2003). In the present study, we investigated the role of HIP1 in NMDA receptor (NMDAR) function by analyzing NMDA-dependent transport and NMDA-induced excitotoxicity in neurons from HIP1-/- mice. HIP1 colocalizes with NMDARs in hippocampal and cortical neurons and affinity purifies with NMDARs by GST (glutathione S-transferase) pull down and coimmunoprecipitation. A profound decrease in NMDA-induced AMPAR internalization of 75% occurs in neurons from HIP1-/- mice compared with wild type, using a quantitative single-cell-based internalization assay. This defect in NMDA-dependent removal of surface AMPARs is in agreement with the observed defect in long-term depression induction in hippocampal brain slices of HIP1-/- mice and supports a role of HIP1 in AMPAR internalization in vivo. HIP1-/- neurons are partially protected from NMDA-induced excitotoxicity as assessed by LDH (lactate dehydrogenase) release, TUNEL (terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick end labeling) and caspase-3 activation assays, which points to a role of HIP1 in NMDA-induced cell death. Interestingly, phosphorylation of Akt and its substrate huntingtin (htt) decreases during NMDA-induced excitotoxicity by 48 and 31%, respectively. This decrease is significantly modulated by HIP1, resulting in 94 and 48% changes in P-Akt and P-htt levels in HIP1-/- neurons, respectively. In summary, we have shown that HIP1 influences important NMDAR functions and that both HIP1 and htt participate in NMDA-induced cell death. These findings may provide novel insights into the cellular mechanisms underlying enhanced NMDA-induced excitotoxicity in Huntington's disease.
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Affiliation(s)
- Martina Metzler
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - Lu Gan
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - Tak Pan Wong
- Department of Medicine and The Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3, and
| | - Lidong Liu
- Department of Medicine and The Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3, and
| | - Jeffrey Helm
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - Lili Liu
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - John Georgiou
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | - Yushan Wang
- Department of Medicine and The Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3, and
| | - Nagat Bissada
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - Kevin Cheng
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
| | - John C. Roder
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | - Yu Tian Wang
- Department of Medicine and The Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3, and
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
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18
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19
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Safwat A, Bissada M, Jackson R, Sakati N, El-Zawahry A, Bissada N. MP-19.06. Urology 2006. [DOI: 10.1016/j.urology.2006.08.566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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20
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Bissada N, Abdallah M, Hammouda H, Aaronson I, Badreldin M, Abdelgawad O. MP-07.05. Urology 2006. [DOI: 10.1016/j.urology.2006.08.293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Safwat A, Bissada N, Kumar U, Taha M, Gafaar A, El-Taher A, Abdalla M. UP-02.94. Urology 2006. [DOI: 10.1016/j.urology.2006.08.838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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22
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Abdallah M, Bissada N, Feinkbeinar A. UP-03.87. Urology 2006. [DOI: 10.1016/j.urology.2006.08.954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Bissada M, Safwat A, Jackson R, Sakati N, El-Zawahry A, Bissada N. MP-16.05. Urology 2006. [DOI: 10.1016/j.urology.2006.08.387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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24
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Safwat A, Bissada A, Taha M, Gafaar A, El-Taher A, Abdalla M, Bissada N. MP-16.04. Urology 2006. [DOI: 10.1016/j.urology.2006.08.386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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25
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26
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Safwat A, Bissada N, Kumar U, Finkbeiner A, Taha M, Gafaar A, El-Taher A, Abdalla M. UP-02.96. Urology 2006. [DOI: 10.1016/j.urology.2006.08.840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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27
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Singaraja RR, Van Eck M, Bissada N, Zimetti F, Collins HL, Hildebrand RB, Hayden A, Brunham LR, Kang MH, Fruchart JC, Van Berkel TJC, Parks JS, Staels B, Rothblat GH, Fiévet C, Hayden MR. Both hepatic and extrahepatic ABCA1 have discrete and essential functions in the maintenance of plasma high-density lipoprotein cholesterol levels in vivo. Circulation 2006; 114:1301-9. [PMID: 16940190 DOI: 10.1161/circulationaha.106.621433] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Extrahepatic tissues have long been considered critical contributors of cholesterol to nascent HDL particles in the reverse cholesterol transport pathway, in which ABCA1 plays the crucial role. Recent studies, however, including both overexpression and deletion of ABCA1 selectively in the liver, have highlighted the primary role of the liver in the maintenance of HDL levels in vivo. METHODS AND RESULTS The availability of mice with complete deletion of ABCA1 (total knockout [TKO]) and with liver-specific deletion of ABCA1 (LSKO) has enabled us to dissect the discrete roles of hepatic relative to extrahepatic ABCA1 in HDL biogenesis. Delivery of adenoviral ABCA1 resulted in selective expression of physiological levels of ABCA1 in the livers of both LSKO and TKO mice, resulting in increased HDL cholesterol (HDL-C). Expression of ABCA1 in the liver of LSKO mice resulted in plasma HDL-C levels that were similar to those in wild-type mice and significantly above those seen in similarly treated TKO mice. HDL particles from ABCA1-expressing LSKO mice were larger and contained significantly increased cholesterol compared with TKO mice. Infusion of human apolipoprotein A-I/phospholipid reconstituted HDL particles normalized plasma HDL-C levels in LSKO mice but had no effect on HDL-C levels in TKO mice. CONCLUSIONS Although hepatic ABCA1 appears crucial for phospholipid transport, extrahepatic tissues play an important role in cholesterol transfer to nascent HDL particles. These data highlight the discrete and specific roles of both liver and extrahepatic ABCA1 in HDL biogenesis in vivo and indicate that ABCA1 shows lipid cargo selectivity depending on its site of expression.
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Affiliation(s)
- Roshni R Singaraja
- Center for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
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28
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Graham RK, Deng Y, Slow EJ, Haigh B, Bissada N, Lu G, Pearson J, Shehadeh J, Bertram L, Murphy Z, Warby SC, Doty CN, Roy S, Wellington CL, Leavitt BR, Raymond LA, Nicholson DW, Hayden MR. Cleavage at the caspase-6 site is required for neuronal dysfunction and degeneration due to mutant huntingtin. Cell 2006; 125:1179-91. [PMID: 16777606 DOI: 10.1016/j.cell.2006.04.026] [Citation(s) in RCA: 477] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Revised: 01/29/2006] [Accepted: 04/03/2006] [Indexed: 11/24/2022]
Abstract
Cleavage of huntingtin (htt) has been characterized in vitro, and accumulation of caspase cleavage fragments represents an early pathological change in brains of Huntington's disease (HD) patients. However, the relationship between htt proteolysis and the pathogenesis of HD is unknown. To determine whether caspase cleavage of htt is a key event in the neuronal dysfunction and selective neurodegeneration in HD, we generated YAC mice expressing caspase-3- and caspase-6-resistant mutant htt. Mice expressing mutant htt, resistant to cleavage by caspase-6 but not caspase-3, maintain normal neuronal function and do not develop striatal neurodegeneration. Furthermore, caspase-6-resistant mutant htt mice are protected against neurotoxicity induced by multiple stressors including NMDA, quinolinic acid (QA), and staurosporine. These results are consistent with proteolysis of htt at the caspase-6 cleavage site being an important event in mediating neuronal dysfunction and neurodegeneration and highlight the significant role of htt proteolysis and excitotoxicity in HD.
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Affiliation(s)
- Rona K Graham
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
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29
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Devon RS, Orban PC, Gerrow K, Barbieri MA, Schwab C, Cao LP, Helm JR, Bissada N, Cruz-Aguado R, Davidson TL, Witmer J, Metzler M, Lam CK, Tetzlaff W, Simpson EM, McCaffery JM, El-Husseini AE, Leavitt BR, Hayden MR. Als2-deficient mice exhibit disturbances in endosome trafficking associated with motor behavioral abnormalities. Proc Natl Acad Sci U S A 2006; 103:9595-600. [PMID: 16769894 PMCID: PMC1480452 DOI: 10.1073/pnas.0510197103] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ALS2 is an autosomal recessive form of spastic paraparesis (motor neuron disease) with juvenile onset and slow progression caused by loss of function of alsin, an activator of Rac1 and Rab5 small GTPases. To establish an animal model of ALS2 and derive insights into the pathogenesis of this illness, we have generated alsin-null mice. Cytosol from brains of Als2(-/-) mice shows marked diminution of Rab5-dependent endosome fusion activity. Furthermore, primary neurons from Als2(-/-) mice show a disturbance in endosomal transport of insulin-like growth factor 1 (IGF1) and BDNF receptors, whereas neuronal viability and endocytosis of transferrin and dextran seem unaltered. There is a significant decrease in the size of cortical motor neurons, and Als2(-/-) mice are mildly hypoactive. Altered trophic receptor trafficking in neurons of Als2(-/-) mice may underlie the histopathological and behavioral changes observed and the pathogenesis of ALS2.
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Affiliation(s)
- R. S. Devon
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - P. C. Orban
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - K. Gerrow
- Department of Psychiatry, Brain Research Centre, University of British Columbia, Vancouver, BC, Canada V6T 2A1
| | - M. A. Barbieri
- Department of Biological Sciences, Florida International University, Miami, FL 33199
| | - C. Schwab
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - L. P. Cao
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - J. R. Helm
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - N. Bissada
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - R. Cruz-Aguado
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - T.-L. Davidson
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - J. Witmer
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - M. Metzler
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - C. K. Lam
- International Collaboration on Repair Discoveries and Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
| | - W. Tetzlaff
- International Collaboration on Repair Discoveries and Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
| | - E. M. Simpson
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - J. M. McCaffery
- **Integrated Imaging Center, Department of Biology, The Johns Hopkins University, Baltimore, MD 21218; and
| | - A. E. El-Husseini
- Department of Psychiatry, Brain Research Centre, University of British Columbia, Vancouver, BC, Canada V6T 2A1
| | - B. R. Leavitt
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
| | - M. R. Hayden
- *Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
- To whom correspondence should be addressed. E-mail:
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30
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Singaraja RR, Stahmer B, Brundert M, Merkel M, Heeren J, Bissada N, Kang M, Timmins JM, Ramakrishnan R, Parks JS, Hayden MR, Rinninger F. Hepatic ATP-binding cassette transporter A1 is a key molecule in high-density lipoprotein cholesteryl ester metabolism in mice. Arterioscler Thromb Vasc Biol 2006; 26:1821-7. [PMID: 16728652 DOI: 10.1161/01.atv.0000229219.13757.a2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Mutations in ATP-binding cassette transporter A1 (ABCA1), the cellular lipid transport molecule mutated in Tangier disease, result in the rapid turnover of high-density lipoprotein (HDL)-associated apolipoproteins that presumably are cleared by the kidneys. However, the role of ABCA1 in the liver for HDL apolipoprotein and cholesteryl ester (CE) catabolism in vivo is unknown. METHODS AND RESULTS Murine HDL was radiolabeled with 125I in its apolipoprotein and with [3H]cholesteryl oleyl ether in its CE moiety. HDL protein and lipid metabolism in plasma and HDL uptake by tissues were investigated in ABCA1-overexpressing bacterial artificial chromosome (BAC)-transgenic (BAC+) mice and in mice harboring deletions of total (ABCA1-/-) and liver-specific ABCA1 (ABCA1(-L/-L)). In BAC+ mice with elevated ABCA1 expression, fractional catabolic rates (FCRs) of both the protein and the lipid tracer were significantly decreased in plasma and in the liver, yielding a diminished hepatic selective CE uptake from HDL. In contrast, ABCA1-/- or ABCA1(-L/-L) mice had significantly increased plasma and liver FCRs for both HDL tracers. An ABCA1 deficiency was associated with increased selective HDL CE uptake by the liver under all experimental conditions. CONCLUSIONS Hepatic ABCA1 has a critical role for HDL catabolism in plasma and for HDL selective CE uptake by the liver.
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Brunham LR, Kruit JK, Iqbal J, Fievet C, Timmins JM, Pape TD, Coburn BA, Bissada N, Staels B, Groen AK, Hussain MM, Parks JS, Kuipers F, Hayden MR. Intestinal ABCA1 directly contributes to HDL biogenesis in vivo. J Clin Invest 2006; 116:1052-62. [PMID: 16543947 PMCID: PMC1401485 DOI: 10.1172/jci27352] [Citation(s) in RCA: 379] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Accepted: 01/17/2006] [Indexed: 11/17/2022] Open
Abstract
Plasma HDL cholesterol levels are inversely related to risk for atherosclerosis. The ATP-binding cassette, subfamily A, member 1 (ABCA1) mediates the rate-controlling step in HDL particle formation, the assembly of free cholesterol and phospholipids with apoA-I. ABCA1 is expressed in many tissues; however, the physiological functions of ABCA1 in specific tissues and organs are still elusive. The liver is known to be the major source of plasma HDL, but it is likely that there are other important sites of HDL biogenesis. To assess the contribution of intestinal ABCA1 to plasma HDL levels in vivo, we generated mice that specifically lack ABCA1 in the intestine. Our results indicate that approximately 30% of the steady-state plasma HDL pool is contributed by intestinal ABCA1 in mice. In addition, our data suggest that HDL derived from intestinal ABCA1 is secreted directly into the circulation and that HDL in lymph is predominantly derived from the plasma compartment. These data establish a critical role for intestinal ABCA1 in plasma HDL biogenesis in vivo.
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Affiliation(s)
- Liam R. Brunham
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Janine K. Kruit
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Jahangir Iqbal
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Catherine Fievet
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Jenelle M. Timmins
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Terry D. Pape
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Bryan A. Coburn
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Nagat Bissada
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Bart Staels
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Albert K. Groen
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - M. Mahmood Hussain
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - John S. Parks
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Folkert Kuipers
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Center for Liver, Digestive and Metabolic Diseases, Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, New York, New York, USA.
Institut Pasteur de Lille and Faculté de Pharmacie, Université de Lille, Lille, France.
Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Experimental Hepatology, Academic Medical Center, Amsterdam, The Netherlands
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Graham RK, Slow EJ, Deng Y, Bissada N, Lu G, Pearson J, Shehadeh J, Leavitt BR, Raymond LA, Hayden MR. Levels of mutant huntingtin influence the phenotypic severity of Huntington disease in YAC128 mouse models. Neurobiol Dis 2005; 21:444-55. [PMID: 16230019 DOI: 10.1016/j.nbd.2005.08.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Revised: 08/08/2005] [Accepted: 08/17/2005] [Indexed: 01/15/2023] Open
Abstract
Huntington disease (HD) is a devastating neuropsychiatric disease caused by expansion of a trinucleotide repeat (CAG) in the HD gene. Neuropathological changes include the appearance of N-terminal huntingtin fragments, decreased brain weight and apoptotic neuronal loss in a select subset of neurons located in the striatum. There is still controversy over whether homozygosity for the mutation in HD is associated with a more severe phenotype. In humans, resolution of this issue has been complicated by the small number of homozygous patients and difficulty in the definition of reliable phenotypic endpoints. In order to definitively determine whether there is a correlation between phenotypic severity and expression levels of mutant huntingtin, we undertook a behavioral and neuropathological assessment of YAC128 mice with varying levels of mutant huntingtin. The results reveal a clear relationship between levels of mutant huntingtin and phenotype defined by earlier age of onset, more rapid progression, enhanced striatal volume loss, acceleration of nuclear huntingtin fragment accumulation and increased sensitivity to NMDAR-mediated excitotoxicity. These results provide clear evidence in vivo supporting a more severe phenotype associated with increased levels of mutant huntingtin as seen in homozygotes for HD.
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Affiliation(s)
- Rona K Graham
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, 980 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4
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33
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Slow EJ, Graham RK, Osmand AP, Devon RS, Lu G, Deng Y, Pearson J, Vaid K, Bissada N, Wetzel R, Leavitt BR, Hayden MR. Absence of behavioral abnormalities and neurodegeneration in vivo despite widespread neuronal huntingtin inclusions. Proc Natl Acad Sci U S A 2005; 102:11402-7. [PMID: 16076956 PMCID: PMC1183566 DOI: 10.1073/pnas.0503634102] [Citation(s) in RCA: 200] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have serendipitously established a mouse that expresses an N-terminal human huntingtin (htt) fragment with an expanded polyglutamine repeat (approximately 120) under the control of the endogenous human promoter (shortstop). Frequent and widespread htt inclusions occur early in shortstop mice. Despite these inclusions, shortstop mice display no clinical evidence of neuronal dysfunction and no neuronal degeneration as determined by brain weight, striatal volume, and striatal neuronal count. These results indicate that htt inclusions are not pathogenic in vivo. In contrast, the full-length yeast artificial chromosome (YAC) 128 model with the identical polyglutamine length and same level of transgenic protein expression as the shortstop demonstrates significant neuronal dysfunction and loss. In contrast to the YAC128 mouse, which demonstrates enhanced susceptibility to excitotoxic death, the shortstop mouse is protected from excitotoxicity, providing in vivo evidence suggesting that neurodegeneration in Huntington disease is mediated by excitotoxic mechanisms.
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Affiliation(s)
- Elizabeth J Slow
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada V5Z 4H4
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34
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Coutinho JM, Singaraja RR, Kang M, Arenillas DJ, Bertram LN, Bissada N, Staels B, Fruchart JC, Fievet C, Joseph-George AM, Wasserman WW, Hayden MR. Complete functional rescue of the ABCA1−/− mouse by human BAC transgenesis. J Lipid Res 2005; 46:1113-23. [PMID: 15772424 DOI: 10.1194/jlr.m400506-jlr200] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Humanized mouse models are useful tools to explore the functional and regulatory differences between human and murine orthologous genes. We have combined a bioinformatics approach and an in vivo approach to assess the functional and regulatory differences between the human and mouse ABCA1 genes. Computational analysis identified significant differences in potential regulatory sites between the human and mouse genes. The effect of these differences was assessed in vivo, using a bacterial artificial chromosome transgenic humanized ABCA1 mouse model that expresses the human gene in the absence of mouse ABCA1. Humanized mice expressed human ABCA1 protein at levels similar to wild-type mice and fully compensated for cholesterol efflux activity and lipid levels seen in ABCA1-deficient mice. Liver X receptor agonist administration resulted in significant increases in HDL values associated with parallel increases in the hepatic ABCA1 protein and mRNA levels in the humanized ABCA1 mice, as seen in the wild-type animals. Our studies indicate that despite differences in potential regulatory regions, the human ABCA1 gene is able to functionally fully compensate for the mouse gene. Our humanized ABCA1 mice can serve as a useful model system for functional analysis of the human ABCA1 gene in vivo and can be used for the generation of potential new therapeutics that target HDL metabolism.
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MESH Headings
- ATP Binding Cassette Transporter 1
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/physiology
- Animals
- Binding Sites
- Blotting, Southern
- Cholesterol/metabolism
- Chromosomes, Artificial, Bacterial
- Computational Biology
- DNA-Binding Proteins/agonists
- Dose-Response Relationship, Drug
- Exons
- Gene Expression Regulation
- Humans
- In Situ Hybridization, Fluorescence
- Lipid Metabolism
- Lipoproteins, HDL/metabolism
- Liver X Receptors
- Mice
- Mice, Knockout
- Mice, Transgenic
- Models, Genetic
- Orphan Nuclear Receptors
- Phylogeny
- RNA/metabolism
- RNA, Messenger/metabolism
- Receptors, Cytoplasmic and Nuclear/agonists
- Software
- Species Specificity
- Tissue Distribution
- Transgenes
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Affiliation(s)
- Jonathan M Coutinho
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
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35
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Van Raamsdonk JM, Pearson J, Rogers DA, Bissada N, Vogl AW, Hayden MR, Leavitt BR. Loss of wild-type huntingtin influences motor dysfunction and survival in the YAC128 mouse model of Huntington disease. Hum Mol Genet 2005; 14:1379-92. [PMID: 15829505 DOI: 10.1093/hmg/ddi147] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Huntington disease (HD) is an adult-onset neurodegenerative disease caused by a toxic gain of function in the huntingtin (htt) protein. The contribution of wild-type htt function to the pathogenesis of HD is currently uncertain. To assess the role of wild-type htt in HD, we generated YAC128 mice that do not express wild-type htt (YAC128-/-) but express the same amount of mutant htt as normal YAC128 mice (YAC128+/+). YAC128-/- mice perform worse than YAC128+/+ mice in the rotarod test of motor coordination (P = 0.001) and are hypoactive compared with YAC128+/+ mice at 2 months (P = 0.003). Striatal neuropathology was not clearly worse in YAC128-/- mice compared with YAC128+/+ mice. There was no significant effect of decreased wild-type htt on striatal volume, neuronal counts or DARPP-32 expression but a modest worsening of striatal neuronal atrophy was evident (6%, P = 0.03). The testis of YAC128+/+ mice showed atrophy and degeneration, which was markedly worsened in the absence of wild-type htt (P = 0.001). YAC128+/+ mice also showed a male specific deficit in survival compared with WT mice which was exacerbated by the loss of wild-type htt (12-month-male survival, P < 0.001). Overall, we demonstrate that the loss of wild-type htt influences motor dysfunction, hyperkinesia, testicular degeneration and impaired lifespan in YAC128 mice. The mild effect of wild-type htt on striatal phenotypes in YAC128 mice suggests that the characteristic striatal neuropathology in HD is caused primarily by the toxicity of mutant htt and that replacement of wild-type htt will not be an adequate treatment for HD.
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Slow EJ, van Raamsdonk J, Rogers D, Coleman SH, Graham RK, Deng Y, Oh R, Bissada N, Hossain SM, Yang YZ, Li XJ, Simpson EM, Gutekunst CA, Leavitt BR, Hayden MR. Selective striatal neuronal loss in a YAC128 mouse model of Huntington disease. Hum Mol Genet 2003; 12:1555-67. [PMID: 12812983 DOI: 10.1093/hmg/ddg169] [Citation(s) in RCA: 597] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
An expanded CAG repeat is the underlying genetic defect in Huntington disease, a disorder characterized by motor, psychiatric and cognitive deficits and striatal atrophy associated with neuronal loss. An accurate animal model of this disease is crucial for elucidation of the underlying natural history of the illness and also for testing experimental therapeutics. We established a new yeast artificial chromosome (YAC) mouse model of HD with the entire human HD gene containing 128 CAG repeats (YAC128) which develops motor abnormalities and age-dependent brain atrophy including cortical and striatal atrophy associated with striatal neuronal loss. YAC128 mice exhibit initial hyperactivity, followed by the onset of a motor deficit and finally hypokinesis. The motor deficit in the YAC128 mice is highly correlated with striatal neuronal loss, providing a structural correlate for the behavioral changes. The natural history of HD-related changes in the YAC128 mice has been defined, demonstrating the presence of huntingtin inclusions after the onset of behavior and neuropathological changes. The HD-related phenotypes of the YAC128 mice show phenotypic uniformity with low inter-animal variability present, which together with the age-dependent striatal neurodegeneration make it an ideal mouse model for the assessment of neuroprotective and other therapeutic interventions.
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Affiliation(s)
- Elizabeth J Slow
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
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37
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Singaraja RR, Fievet C, Castro G, James ER, Hennuyer N, Clee SM, Bissada N, Choy JC, Fruchart JC, McManus BM, Staels B, Hayden MR. Increased ABCA1 activity protects against atherosclerosis. J Clin Invest 2002; 110:35-42. [PMID: 12093886 PMCID: PMC151034 DOI: 10.1172/jci15748] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The ABC transporter ABCA1 plays a key role in the first steps of the reverse cholesterol transport pathway by mediating lipid efflux from macrophages. Previously, it was demonstrated that human ABCA1 overexpression in vivo in transgenic mice results in a mild elevation of plasma HDL levels and increased efflux of cholesterol from macrophages. In this study, we determined the effect of overexpression of ABCA1 on atherosclerosis development. Human ABCA1 transgenic mice (BAC(+)) were crossed with ApoE(-/-) mice, a strain that spontaneously develop atherosclerotic lesions. BAC(+)ApoE(-/-) mice developed dramatically smaller, less-complex lesions as compared with their ApoE(-/-) counterparts. In addition, there was increased efflux of cholesterol from macrophages isolated from the BAC(+)ApoE(-/-) mice. Although the increase in plasma HDL cholesterol levels was small, HDL particles from BAC(+)ApoE(-/-) mice were significantly better acceptors of cholesterol. Lipid analysis of HDL particles from BAC(+)ApoE(-/-) mice revealed an increase in phospholipid levels, which was correlated significantly with their ability to enhance cholesterol efflux.
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Affiliation(s)
- Roshni R Singaraja
- Centre for Molecular Medicine and Therapeutics, Children's and Women's Hospital, University of British Columbia, 950 West 28th Avenue, Vancouver, British Columbia V5Z 4H4, Canada
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38
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Singaraja RR, Fievet C, Castro G, James ER, Hennuyer N, Clee SM, Bissada N, Choy JC, Fruchart JC, McManus BM, Staels B, Hayden MR. Increased ABCA1 activity protects against atherosclerosis. J Clin Invest 2002. [DOI: 10.1172/jci0215748] [Citation(s) in RCA: 206] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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39
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Wellington CL, Walker EKY, Suarez A, Kwok A, Bissada N, Singaraja R, Yang YZ, Zhang LH, James E, Wilson JE, Francone O, McManus BM, Hayden MR. ABCA1 mRNA and protein distribution patterns predict multiple different roles and levels of regulation. J Transl Med 2002; 82:273-83. [PMID: 11896206 DOI: 10.1038/labinvest.3780421] [Citation(s) in RCA: 227] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Mutations in ABCA1 cause the allelic disorders familial hypolipoproteinemia and Tangier Disease. To identify where ABCA1 was likely to have a functional role, we determined the cellular and tissue-specific patterns of murine ABCA1 expression. RT-PCR and Western blot analysis on dissected murine tissues demonstrated broad expression of ABCA1 mRNA and protein in many tissues with prominent protein expression in liver, testis, and adrenal tissue. In situ hybridization and immunohistochemistry experiments demonstrated specific patterns of ABCA1 expression at the cellular level, with hepatocytes, the epithelial lining of the digestive system and bladder, the proximal convoluted tubule of the kidney, and Purkinje and cortical pyramidal neurons containing abundant ABCA1 protein. Significant discordance between relative mRNA and protein expression patterns suggests the possibility of post-transcriptional regulation of ABCA1 expression in selected cells or tissues. We also show that ABCA1 protein levels are up-regulated specifically in the liver after exposure to an atherogenic diet for 7 days, supporting a major role for the liver in dietary modulation of HDL-C levels. Our observations show that ABCA1 is expressed in a pattern consistent with its role in HDL-C metabolism. Additionally, ABCA1 may have important functional roles in other cell types independent of HDL-C regulation.
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Affiliation(s)
- Cheryl L Wellington
- Centre for Molecular Medicine and Therapeutics, St. Paul's Hospital/Providence Health Care-University of British Columbia, Canada
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40
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Singaraja RR, Bocher V, James ER, Clee SM, Zhang LH, Leavitt BR, Tan B, Brooks-Wilson A, Kwok A, Bissada N, Yang YZ, Liu G, Tafuri SR, Fievet C, Wellington CL, Staels B, Hayden MR. Human ABCA1 BAC transgenic mice show increased high density lipoprotein cholesterol and ApoAI-dependent efflux stimulated by an internal promoter containing liver X receptor response elements in intron 1. J Biol Chem 2001; 276:33969-79. [PMID: 11423537 DOI: 10.1074/jbc.m102503200] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
By using BAC transgenic mice, we have shown that increased human ABCA1 protein expression results in a significant increase in cholesterol efflux in different tissues and marked elevation in high density lipoprotein (HDL)-cholesterol levels associated with increases in apoAI and apoAII. Three novel ABCA1 transcripts containing three different transcription initiation sites that utilize sequences in intron 1 have been identified. In BAC transgenic mice there is an increased expression of ABCA1 protein, but the distribution of the ABCA1 product in different cells remains similar to wild type mice. An internal promoter in human intron 1 containing liver X response elements is functional in vivo and directly contributes to regulation of the human ABCA1 gene in multiple tissues and to raised HDL cholesterol, apoAI, and apoAII levels. A highly significant relationship between raised protein levels, increased efflux, and level of HDL elevation is evident. These data provide proof of the principle that increased human ABCA1 efflux activity is associated with an increase in HDL levels in vivo.
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MESH Headings
- ATP Binding Cassette Transporter 1
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/physiology
- Animals
- Apolipoprotein A-I/metabolism
- Base Sequence
- COS Cells
- Cell Line
- Cells, Cultured
- Cholesterol/metabolism
- Cholesterol, HDL/metabolism
- Cloning, Molecular
- DNA-Binding Proteins
- Humans
- Immunohistochemistry
- Introns
- Lipids/blood
- Liver/metabolism
- Liver X Receptors
- Macrophages/metabolism
- Mice
- Mice, Transgenic
- Models, Genetic
- Molecular Sequence Data
- Orphan Nuclear Receptors
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Receptors, Cytoplasmic and Nuclear
- Receptors, Retinoic Acid/genetics
- Receptors, Thyroid Hormone/genetics
- Response Elements
- Reverse Transcriptase Polymerase Chain Reaction
- Transcriptional Activation
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- R R Singaraja
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics and Children's and Women's Hospital, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
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41
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Clee SM, Bissada N, Miao F, Miao L, Marais AD, Henderson HE, Steures P, McManus J, McManus B, LeBoeuf RC, Kastelein JJ, Hayden MR. Plasma and vessel wall lipoprotein lipase have different roles in atherosclerosis. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32399-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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42
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Clee SM, Bissada N, Miao F, Miao L, Marais AD, Henderson HE, Steures P, McManus J, McManus B, LeBoeuf RC, Kastelein JJ, Hayden MR. Plasma and vessel wall lipoprotein lipase have different roles in atherosclerosis. J Lipid Res 2000; 41:521-31. [PMID: 10744772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Lipoprotein lipase (LPL) is a key enzyme in lipoprotein metabolism, and has been hypothesized to exert either pro- or anti-atherogenic effects, depending on its localization. Decreased plasma LPL activity is associated with the high triglyceride (TG);-low HDL phenotype that is often observed in patients with premature vascular disease. In contrast, in the vessel wall, decreased LPL may be associated with less lipoprotein retention due to many potential mechanisms and, therefore, decreased foam cell formation. To directly assess this hypothesis, we have distinguished between the effects of variations in plasma and/or vessel wall LPL on atherosclerosis susceptibility in apoE-deficient mice. Reduced LPL in both plasma and vessel wall (LPL(+/-)E(-/-)) was associated with increased TG and increased total cholesterol (TC) compared with LPL(+/+)E(-/-) sibs. However despite their dyslipidemia, LPL(+/-)E(-/-) mice had significantly reduced lesion areas compared to the LPL(+/+)E(-/-) mice. Thus, decreased vessel wall LPL was associated with decreased lesion formation even in the presence of reduced plasma LPL activity. In contrast, transgenic mice with increased plasma LPL but with no increase in LPL expression in macrophages, and thus the vessel wall, had decreased TG and TC and significantly decreased lesion areas compared with LPL(+/+)E(-/-) mice. This demonstrates that increased plasma LPL activity alone, in the absence of an increase in vessel wall LPL, is associated with reduced susceptibility to atherosclerosis. Taken together, these results provide in vivo evidence that the contribution of LPL to atherogenesis is significantly influenced by the balance between vessel wall protein (pro-atherogenic) and plasma activity (anti-atherogenic).
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Affiliation(s)
- S M Clee
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada V5Z 4H4
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Hodgson JG, Agopyan N, Gutekunst CA, Leavitt BR, LePiane F, Singaraja R, Smith DJ, Bissada N, McCutcheon K, Nasir J, Jamot L, Li XJ, Stevens ME, Rosemond E, Roder JC, Phillips AG, Rubin EM, Hersch SM, Hayden MR. A YAC mouse model for Huntington's disease with full-length mutant huntingtin, cytoplasmic toxicity, and selective striatal neurodegeneration. Neuron 1999; 23:181-92. [PMID: 10402204 DOI: 10.1016/s0896-6273(00)80764-3] [Citation(s) in RCA: 594] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have produced yeast artificial chromosome (YAC) transgenic mice expressing normal (YAC18) and mutant (YAC46 and YAC72) huntingtin (htt) in a developmental and tissue-specific manner identical to that observed in Huntington's disease (HD). YAC46 and YAC72 mice show early electrophysiological abnormalities, indicating cytoplasmic dysfunction prior to observed nuclear inclusions or neurodegeneration. By 12 months of age, YAC72 mice have a selective degeneration of medium spiny neurons in the lateral striatum associated with the translocation of N-terminal htt fragments to the nucleus. Neurodegeneration can be present in the absence of macro- or microaggregates, clearly showing that aggregates are not essential to initiation of neuronal death. These mice demonstrate that initial neuronal cytoplasmic toxicity is followed by cleavage of htt, nuclear translocation of htt N-terminal fragments, and selective neurodegeneration.
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Affiliation(s)
- J G Hodgson
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
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44
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Bissada N. Attacking gum disease. Health News 1998; 4:4. [PMID: 9825709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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45
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Ehrenborg E, Clee SM, Pimstone SN, Reymer PW, Benlian P, Hoogendijk CF, Davis HJ, Bissada N, Miao L, Gagné SE, Greenberg LJ, Henry R, Henderson H, Ordovas JM, Schaefer EJ, Kastelein JJ, Kotze MJ, Hayden MR. Ethnic variation and in vivo effects of the -93t-->g promoter variant in the lipoprotein lipase gene. Arterioscler Thromb Vasc Biol 1997; 17:2672-8. [PMID: 9409241 DOI: 10.1161/01.atv.17.11.2672] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recently, a (t-->g) transition at nucleotide -93 in the lipoprotein lipase (LPL) gene promoter has been observed in Caucasians. Here, we have compared the frequency of the -93g carriers in three distinct populations (Caucasians, South African Blacks, and Chinese). The carrier frequency in the Caucasian population was 1.7% (4/232), which was in contrast to the South African Black population, which had a frequency for this allele of 76.4% (123/161) of the individuals tested. This transition was not observed in the Chinese population under study. Near complete linkage disequilibrium between the -93g and the previously described D9N mutation was observed in the Caucasian population but not in South African Blacks. To further assess the ancestral origins of these DNA changes, DNA haplotyping using a CA repeat 5' to these substitutions was performed. The -93t allele was associated with only a few specific dinucleotide repeat sizes. In contrast, the -93g allele occurred on chromosomes with many different repeat lengths. The broad distribution of repeats on -93g carrying chromosomes, their high frequency in the South African Black population, and the conservation of the -93g allele among different species may suggest that the -93g allele is the ancestral allele on which a transition to t and the D9N mutations arose. The very high frequency of the -93g allele distinct from the N9 allele in a cohort of Black South Africans allowed us to specifically assess the phenotypic effects of the -93g allele on lipids. Individuals homozygous for the g allele at -93 showed mildly decreased triglycerides compared with individuals homozygous for the t allele (1.14 +/- 0.66 mmol/L versus 0.82 +/- 0.3; P = .04). Thus, the -93g allele in this cohort is associated with low plasma triglyceride levels.
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Affiliation(s)
- E Ehrenborg
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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Clee SM, Zhang H, Bissada N, Miao L, Ehrenborg E, Benlian P, Shen GX, Angel A, LeBoeuf RC, Hayden MR. Relationship between lipoprotein lipase and high density lipoprotein cholesterol in mice: modulation by cholesteryl ester transfer protein and dietary status. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)37138-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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47
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Clee SM, Zhang H, Bissada N, Miao L, Ehrenborg E, Benlian P, Shen GX, Angel A, LeBoeuf RC, Hayden MR. Relationship between lipoprotein lipase and high density lipoprotein cholesterol in mice: modulation by cholesteryl ester transfer protein and dietary status. J Lipid Res 1997; 38:2079-89. [PMID: 9374130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Plasma lipoprotein lipase (LPL) activity correlates with high density lipoprotein (HDL) cholesterol levels in humans. However, in several mouse models created either through transgenesis or targeted inactivation of LPL, no significant changes in HDL cholesterol values have been evident. One possible explanation for this species difference could be the absence of plasma cholesteryl ester transfer protein (CETP) activity in mice. To explore this possibility and further investigate interactions between LPL and CETP modulating HDL cholesterol levels in vivo, we examined the relationship between LPL activity and HDL levels in mice expressing the simian CETP transgene, compared with littermates not carrying the CETP gene. On a chow diet, increasing LPL activity was associated with a trend towards increased HDL levels (51 +/- 29 vs. 31 +/- 4 mg/dL highest vs. lowest tertiles of LPL activity, P = 0.07) in mice expressing CETP, while no such effects were seen in the absence of CETP (65 +/- 12 vs. 61 +/- 15 mg/ dL). Furthermore, in the presence of CETP, a significant positive correlation between LPL activity and HDL cholesterol was evident (r = 0.15, P = 0.006), while in the absence of CETP no such correlation was detected (r = 0.15, P = 0.36), highlighting the interactions between LPL and CETP in vivo. When mice were challenged with a high fat, high carbohydrate diet, strong correlations between LPL activity and HDL cholesterol were seen in both the presence (r = 0.45, P = 0.03) and absence (r = 0.73, P < 0.001) of CETP. Therefore, under altered metabolic contexts, such as those induced by dietary challenge, the relation between LPL activity and HDL cholesterol may also become evident. Here we have shown that both genetic and environmental factors may modulate the association between LPL activity and HDL cholesterol, and provide explanations for the absence of any changes in HDL values in mice either transgenic or with targeted disruption of the LPL gene.
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Affiliation(s)
- S M Clee
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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48
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Hodgson JG, Smith DJ, McCutcheon K, Koide HB, Nishiyama K, Dinulos MB, Stevens ME, Bissada N, Nasir J, Kanazawa I, Disteche CM, Rubin EM, Hayden MR. Human huntingtin derived from YAC transgenes compensates for loss of murine huntingtin by rescue of the embryonic lethal phenotype. Hum Mol Genet 1996; 5:1875-85. [PMID: 8968738 DOI: 10.1093/hmg/5.12.1875] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Huntington disease (HD) is caused by expansion of a CAG trinucleotide repeat in exon 1 of a novel gene. The HD protein (huntingtin) plays a critical role in early embryonic development since homozygous targeted disruption of the murine HD gene results in embryonic lethality by day 7.5. To rescue this phenotype by transgene based huntingtin expression it is therefore essential to express the protein early enough in development in the appropriate cells. Since YAC based transgenes are known to be regulated in an appropriate temporal and tissue-specific manner, we sought to rescue the embryonic lethality by breeding YAC transgenic mice expressing human huntingtin with mice heterozygous for the targeted disruption. We generated viable offspring homozygous for the disrupted murine HD gene but expressing human huntingtin derived from the YAC. This result clearly shows that YAC transgene based expression of huntingtin occurs prior to 7.5 days gestation. Additionally, we show that human huntingtin expression in YAC transgenic mice follows an identical tissue distribution and subcellular localisation pattern as that of the murine endogenous protein and that expression levels of 2-3 times endogenous can be achieved. This shows that human huntingtin under the influence of its native promoter, despite differences to the murine protein, is functional in a murine background and can compensate for loss of the murine protein. These results show that YAC transgenic approaches are a particularly promising route to producing an animal model for disorders associated with CAG expansion.
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Affiliation(s)
- J G Hodgson
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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Sanders R, Bissada N, Curry N, Gordon B. Clinical spectrum of adrenal myelolipoma: analysis of 8 tumors in 7 patients. J Urol 1995; 153:1791-3. [PMID: 7752318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Adrenal myelolipoma is a rare, benign, and biochemically nonfunctioning tumor. Most patients with adrenal myelolipoma are asymptomatic and the condition is discovered incidentally at autopsy. Review of the literature reveals 70 patients with surgically documented adrenal myelolipoma. We report 7 additional patients with 8 adrenal myelolipomas, of whom 5 underwent surgical removal because of tumor size, unusual imaging features or symptomatology. Of our patients 4 had symptomatic lesions requiring surgical removal, while 1 had an adrenal myelolipoma that was discovered intraoperatively. Of the remaining 2 patients 1 had a small (3 cm.) lesion discovered incidentally on excretory urography and 1 had bilateral adrenal myelolipoma discovered incidentally on computerized tomography.
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Affiliation(s)
- R Sanders
- Medical University of South Carolina, Charleston 29425, USA
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Tze WJ, Cheung SS, Tai J, Bissada N, Tsang A, Yep W. Prolongation of pig islet xenograft survival in polysulfone fiber coil. Transplant Proc 1994; 26:3510-1. [PMID: 7998253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- W J Tze
- Department of Pediatrics and Pathology, University of British Columbia, Vancouver, Canada
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