1
|
Lin H, Mensch J, Haschke M, Jäger K, Köttgen B, Dernedde J, Orsó E, Walter M. Establishment and Characterization of hTERT Immortalized Hutchinson–Gilford Progeria Fibroblast Cell Lines. Cells 2022; 11:cells11182784. [PMID: 36139359 PMCID: PMC9497314 DOI: 10.3390/cells11182784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 11/22/2022] Open
Abstract
Hutchinson–Gilford progeria syndrome (HGPS) is a rare premature aging syndrome caused by a dominant mutation in the LMNA gene. Previous research has shown that the ectopic expression of the catalytic subunit of telomerase (hTERT) can elongate the telomeres of the patients’ fibroblasts. Here, we established five immortalized HGP fibroblast cell lines using retroviral infection with the catalytic subunit of hTERT. Immortalization enhanced the proliferative life span by at least 50 population doublings (PDs). The number of cells with typical senescence signs was reduced by 63 + 17%. Furthermore, the growth increase and phenotype improvement occurred with a lag phase of 50–100 days and was not dependent on the degree of telomere elongation. The initial telomeric stabilization after hTERT infection and relatively low amounts of hTERT mRNA were sufficient for the phenotype improvement but the retroviral infection procedure was associated with transient cell stress. Our data have implications for therapeutic strategies in HGP and other premature aging syndromes.
Collapse
Affiliation(s)
- Haihuan Lin
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
| | - Juliane Mensch
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, 18057 Rostock, Germany
| | - Maria Haschke
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, 18057 Rostock, Germany
| | - Kathrin Jäger
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, 18057 Rostock, Germany
| | - Brigitte Köttgen
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
| | - Jens Dernedde
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
| | - Evelyn Orsó
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Michael Walter
- Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, 13353 Berlin, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, 18057 Rostock, Germany
- Correspondence:
| |
Collapse
|
2
|
Jäger K, Mensch J, Grimmig ME, Neuner B, Gorzelniak K, Türkmen S, Demuth I, Hartmann A, Hartmann C, Wittig F, Sporbert A, Hermann A, Fuellen G, Möller S, Walter M. A conserved long-distance telomeric silencing mechanism suppresses mTOR signaling in aging human fibroblasts. SCIENCE ADVANCES 2022; 8:eabk2814. [PMID: 35977016 PMCID: PMC9385144 DOI: 10.1126/sciadv.abk2814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Telomeres are repetitive nucleotide sequences at the ends of each chromosome. It has been hypothesized that telomere attrition evolved as a tumor suppressor mechanism in large long-lived species. Long telomeres can silence genes millions of bases away through a looping mechanism called telomere position effect over long distances (TPE-OLD). The function of this silencing mechanism is unknown. We determined a set of 2322 genes with high positional conservation across replicatively aging species that includes known and candidate TPE-OLD genes that may mitigate potentially harmful effects of replicative aging. Notably, we identified PPP2R2C as a tumor suppressor gene, whose up-regulation by TPE-OLD in aged human fibroblasts leads to dephosphorylation of p70S6 kinase and mammalian target of rapamycin suppression. A mechanistic link between telomeres and a tumor suppressor mechanism supports the hypothesis that replicative aging fulfills a tumor suppressor function and motivates previously unknown antitumor and antiaging strategies.
Collapse
Affiliation(s)
- Kathrin Jäger
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, University of Rostock, Rostock, Germany
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany
| | - Juliane Mensch
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, University of Rostock, Rostock, Germany
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany
| | - Maria Elisabeth Grimmig
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, University of Rostock, Rostock, Germany
| | - Bruno Neuner
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Berlin, Germany
| | - Kerstin Gorzelniak
- Unfallkrankenhaus Berlin, Institute of Laboratory Medicine, Berlin, Germany
| | - Seval Türkmen
- LNS Hematooncogenetics, National Center of Genetics Luxembourg, Dudelange, Luxemburg
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Medical Genetics and Human Genetics, Berlin, Germany
| | - Ilja Demuth
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Endocrinology and Metabolism, Berlin, Germany
- Berlin Institute of Health at Charité–Universitätsmedizin Berlin, BCRT - Berlin Institute of Health Center for Regenerative Therapies, Berlin, Germany
| | - Alexander Hartmann
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, University of Rostock, Rostock, Germany
| | - Christiane Hartmann
- Translational Neurodegeneration Section “Albrecht-Kossel”, Department of Neurology, Rostock University Medical Center, University of Rostock, 18147 Rostock, Germany
| | - Felix Wittig
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, University of Rostock, Rostock, Germany
| | - Anje Sporbert
- Advanced Light Microscopy, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Andreas Hermann
- Translational Neurodegeneration Section “Albrecht-Kossel”, Department of Neurology, Rostock University Medical Center, University of Rostock, 18147 Rostock, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) Rostock/Greifswald, Rostock, Germany
- Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, Rostock, Germany
| | - Georg Fuellen
- Institute for Biostatistics and Informatics in Medicine and Ageing Research, Rostock University Medical Center, Rostock, Germany
| | - Steffen Möller
- Institute for Biostatistics and Informatics in Medicine and Ageing Research, Rostock University Medical Center, Rostock, Germany
| | - Michael Walter
- Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, University of Rostock, Rostock, Germany
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany
- Corresponding author.
| |
Collapse
|
3
|
Telomere attrition and dysfunction: a potential trigger of the progeroid phenotype in nijmegen breakage syndrome. Aging (Albany NY) 2020; 12:12342-12375. [PMID: 32564008 PMCID: PMC7343506 DOI: 10.18632/aging.103453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 05/27/2020] [Indexed: 12/17/2022]
Abstract
Background: Nibrin, as part of the NBN/MRE11/RAD50 complex, is mutated in Nijmegen breakage syndrome (NBS), which leads to impaired DNA damage response and lymphoid malignancy. Results: Telomere length (TL) was markedly reduced in homozygous patients (and comparably so in all chromosomes) by ~40% (qPCR) and was slightly reduced in NBS heterozygotes older than 30 years (~25% in qPCR), in accordance with the respective cancer rates. Humanized cancer-free NBS mice had normal TL. Telomere elongation was inducible by telomerase and/or alternative telomere lengthening but was associated with abnormal expression of telomeric genes involved in aging and/or cell growth. Lymphoblastoid cells from NBS patients with long survival times (>12 years) displayed the shortest telomeres and low caspase 7 activity. Conclusions: NBS is a secondary telomeropathy. The two-edged sword of telomere attrition enhances the cancer-prone situation in NBS but can also lead to a relatively stable cellular phenotype in tumor survivors. Results suggest a modular model for progeroid syndromes with abnormal expression of telomeric genes as a molecular basis. Methods: We studied TL and function in 38 homozygous individuals, 27 heterozygotes, one homozygous fetus, six NBS lymphoblastoid cell lines, and humanized NBS mice, all with the same founder NBN mutation: c.657_661del5.
Collapse
|
4
|
Pieralice S, Vari R, Minutolo A, Maurizi AR, Fioriti E, Napoli N, Pozzilli P, Manfrini S, Maddaloni E. Biomarkers of response to alpha-lipoic acid ± palmitoiletanolamide treatment in patients with diabetes and symptoms of peripheral neuropathy. Endocrine 2019; 66:178-184. [PMID: 30949911 DOI: 10.1007/s12020-019-01917-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 03/27/2019] [Indexed: 12/19/2022]
Abstract
PURPOSE To evaluate the effect of oral alpha-lipoic acid (ALA) ± palmitoyl-ethanolamide (PEA) on neuropathic symptoms in patients with diabetic peripheral neuropathy (DPN) and to identify factors related to the efficacy of the treatment. METHODS This is a retrospective observational pilot study evaluating 49 patients with diabetes and positive Neuropathy Symptoms Score (NSS). Clinical and biochemical variables, including NSS, were compared between untreated patients and patients treated with oral 600 mg/day ALA ± 600 mg/day PEA at baseline (first occurrence of NSS ≥ 3) and at least 2 months after baseline. Number of days between treatment initiation and symptoms' relief and related factors were also investigated. RESULTS Thirty subjects were treated with ALA ± PEA and 19 subjects did not receive any specific treatment for neuropathy symptoms. Follow-up visits occurred after 98 ± 46 days. NSS significantly decreased in patients treated with ALA ± PEA (5.4 ± 1.3 at baseline vs. 1.7 ± 2.4 at follow-up, p < 0.001), but not in untreated patients (p = 0.164). Subjects treated with ALA ± PEA reported a mean time from treatment initiation to symptoms' relief of 18.4 ± 9.0 days. The number of days of treatment needed for symptoms' relief was inversely related to HDL-cholesterol levels (r = -0.503, p = 0.010) and to eGFR (r = -0.428, p = 0.033), whereas there was no significant relationship between time to symptoms' relief and age, HbA1c, lipid profile and the severity of symptoms at baseline. CONCLUSIONS This study documents that oral administration of ALA ± PEA helps in controlling neuropathy symptoms in diabetes. Moreover, our data show that higher HDL-c levels and better renal function are associated to a faster therapeutic effect, suggesting them as biomarkers of response to therapy with ALA ± PEA.
Collapse
Affiliation(s)
- Silvia Pieralice
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Riccardo Vari
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Alessandra Minutolo
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Anna Rita Maurizi
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Elvira Fioriti
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Nicola Napoli
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Paolo Pozzilli
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Silvia Manfrini
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy
| | - Ernesto Maddaloni
- Department of Medicine, Unit of Endocrinology and Diabetes, Campus Bio-Medico University of Rome, Rome, Italy.
| |
Collapse
|
5
|
Heverin M, Ali Z, Olin M, Tillander V, Joibari MM, Makoveichuk E, Leitersdorf E, Warner M, Olivercrona G, Gustafsson JÅ, Björkhem I. On the regulatory importance of 27-hydroxycholesterol in mouse liver. J Steroid Biochem Mol Biol 2017; 169:10-21. [PMID: 26851362 DOI: 10.1016/j.jsbmb.2016.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 02/01/2016] [Accepted: 02/02/2016] [Indexed: 01/17/2023]
Abstract
27-Hydroxycholesterol (27OH) is a strong suppressor of cholesterol synthesis and a weak activator of LXR in vitro. The regulatory importance of 27OH in vivo is controversial. Here we utilized male mice with increased levels of 27OH either due to increased production (CYP27A1 transgenic mice) or reduced metabolism (Cyp7b1-/- mice). We also used mice lacking 27OH due to a knockout of Cyp27a1. The latter mice were treated with cholic acid to compensate for reduced bile acid synthesis. The effects of the different levels of 27OH on Srebp- and other LXR-regulated genes in the liver were investigated. In the liver of CYP27tg mice we found a modest increase of the mRNA levels corresponding to the LXR target genes Cyp7b1 and Abca1. A number of other LXR-regulated genes were not affected. The effect on Abca1 mRNA was not seen in the liver of Cyp7b1-/- mice. There were little or no effects on cholesterol synthesis. In the liver of the Cyp27-/- mice treated with 0.025% cholic acid there was no significant effect of the knockout on the LXR target genes. In a previous work triple-knockout mice deficient in the biosynthesis of 24S-hydroxycholesterol, 25-hydroxycholesterol and 27OH were shown to have impaired response to dietary cholesterol, suggesting side-chain oxidized oxysterols to be mediators in cholesterol-induced effects on LXR target genes at a transcriptional level (Chen W. et al., Cell Metab. 5 (2007) 73-79). The hydroxylated oxysterol responsible for the effect was not defined. We show here that treatment of wildtype mice with dietary cholesterol under the same conditions as in the above study induced the LXR target genes Lpl, Abcg8 and Srebp1c in wild type mice but failed to activate the same genes in mice lacking 27-hydroxycholesterol due to a knockout of Cyp27. We failed to demonstrate the above effects at the protein level (Abcg8) or at the activity level (Lpl). The results suggest that 27OH is not an important regulator of Srebp- or LXR regulated genes under basal conditions in mouse liver. On the other hand 27OH appears to mediate cholesterol-induced effects on some LXR target genes at a transcriptional level under some in vivo conditions.
Collapse
Affiliation(s)
- Maura Heverin
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Zeina Ali
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Maria Olin
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Veronika Tillander
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | | | - Elena Makoveichuk
- Department of Medical Biosciences/Physiological Chemistry, Umeå University, Umeå, Sweden
| | - Eran Leitersdorf
- Department of Medicine B, Hadassah-Hebrew University Hospital, Israel
| | - Margret Warner
- Center for Nuclear Receptors and Cell Signaling, University of Houston, TX, USA
| | - Gunilla Olivercrona
- Department of Medical Biosciences/Physiological Chemistry, Umeå University, Umeå, Sweden
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, University of Houston, TX, USA
| | - Ingemar Björkhem
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
| |
Collapse
|
6
|
Jäger K, Walter M. Therapeutic Targeting of Telomerase. Genes (Basel) 2016; 7:genes7070039. [PMID: 27455328 PMCID: PMC4962009 DOI: 10.3390/genes7070039] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/16/2016] [Accepted: 06/24/2016] [Indexed: 12/20/2022] Open
Abstract
Telomere length and cell function can be preserved by the human reverse transcriptase telomerase (hTERT), which synthesizes the new telomeric DNA from a RNA template, but is normally restricted to cells needing a high proliferative capacity, such as stem cells. Consequently, telomerase-based therapies to elongate short telomeres are developed, some of which have successfully reached the stage I in clinical trials. Telomerase is also permissive for tumorigenesis and 90% of all malignant tumors use telomerase to obtain immortality. Thus, reversal of telomerase upregulation in tumor cells is a potential strategy to treat cancer. Natural and small-molecule telomerase inhibitors, immunotherapeutic approaches, oligonucleotide inhibitors, and telomerase-directed gene therapy are useful treatment strategies. Telomerase is more widely expressed than any other tumor marker. The low expression in normal tissues, together with the longer telomeres in normal stem cells versus cancer cells, provides some degree of specificity with low risk of toxicity. However, long term telomerase inhibition may elicit negative effects in highly-proliferative cells which need telomerase for survival, and it may interfere with telomere-independent physiological functions. Moreover, only a few hTERT molecules are required to overcome senescence in cancer cells, and telomerase inhibition requires proliferating cells over a sufficient number of population doublings to induce tumor suppressive senescence. These limitations may explain the moderate success rates in many clinical studies. Despite extensive studies, only one vaccine and one telomerase antagonist are routinely used in clinical work. For complete eradication of all subpopulations of cancer cells a simultaneous targeting of several mechanisms will likely be needed. Possible technical improvements have been proposed including the development of more specific inhibitors, methods to increase the efficacy of vaccination methods, and personalized approaches. Telomerase activation and cell rejuvenation is successfully used in regenerative medicine for tissue engineering and reconstructive surgery. However, there are also a number of pitfalls in the treatment with telomerase activating procedures for the whole organism and for longer periods of time. Extended cell lifespan may accumulate rare genetic and epigenetic aberrations that can contribute to malignant transformation. Therefore, novel vector systems have been developed for a 'mild' integration of telomerase into the host genome and loss of the vector in rapidly-proliferating cells. It is currently unclear if this technique can also be used in human beings to treat chronic diseases, such as atherosclerosis.
Collapse
Affiliation(s)
- Kathrin Jäger
- Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
| | - Michael Walter
- Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
- Labor Berlin-Charité Vivantes Services GmbH, Sylter Str. 2, Berlin 13353, Germany.
| |
Collapse
|
7
|
Ito A, Hong C, Rong X, Zhu X, Tarling EJ, Hedde PN, Gratton E, Parks J, Tontonoz P. LXRs link metabolism to inflammation through Abca1-dependent regulation of membrane composition and TLR signaling. eLife 2015; 4:e08009. [PMID: 26173179 PMCID: PMC4517437 DOI: 10.7554/elife.08009] [Citation(s) in RCA: 204] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/13/2015] [Indexed: 01/22/2023] Open
Abstract
The liver X receptors (LXRs) are transcriptional regulators of lipid homeostasis that also have potent anti-inflammatory effects. The molecular basis for their anti-inflammatory effects is incompletely understood, but has been proposed to involve the indirect tethering of LXRs to inflammatory gene promoters. Here we demonstrate that the ability of LXRs to repress inflammatory gene expression in cells and mice derives primarily from their ability to regulate lipid metabolism through transcriptional activation and can occur in the absence of SUMOylation. Moreover, we identify the putative lipid transporter Abca1 as a critical mediator of LXR's anti-inflammatory effects. Activation of LXR inhibits signaling from TLRs 2, 4 and 9 to their downstream NF-κB and MAPK effectors through Abca1-dependent changes in membrane lipid organization that disrupt the recruitment of MyD88 and TRAF6. These data suggest that a common mechanism-direct transcriptional activation-underlies the dual biological functions of LXRs in metabolism and inflammation.
Collapse
Affiliation(s)
- Ayaka Ito
- Department of Pathology and Laboratory Medicine, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Cynthia Hong
- Department of Pathology and Laboratory Medicine, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Xin Rong
- Department of Pathology and Laboratory Medicine, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Xuewei Zhu
- Department of Internal Medicine-Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Elizabeth J Tarling
- Department of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Per Niklas Hedde
- Laboratory of Fluorescence Dynamics, Biomedical Engineering Department, Center for Complex Biological Systems, University of California, Irvine, Irvine, United States
| | - Enrico Gratton
- Laboratory of Fluorescence Dynamics, Biomedical Engineering Department, Center for Complex Biological Systems, University of California, Irvine, Irvine, United States
| | - John Parks
- Department of Internal Medicine-Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Peter Tontonoz
- Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| |
Collapse
|
8
|
Nunes VS, Panzoldo NB, Leança CC, Parra ES, Zago VS, da Silva EJ, Cazita PM, Nakandakare ER, de Faria EC, Quintão EC. Increased 27-hydroxycholesterol plasma level in men with low high density lipoprotein-cholesterol may circumvent their reduced cell cholesterol efflux rate. Clin Chim Acta 2014; 433:169-73. [DOI: 10.1016/j.cca.2014.03.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 10/25/2022]
|
9
|
Abstract
PURPOSE OF REVIEW To examine the recent advances in our knowledge of HDL metabolism, composition, function, and coronary heart disease (CHD), as well as marked HDL deficiency states because of mutations in the apolipoprotein (apo) A-I, ATP-binding cassette transfer protein A1 and lecithin cholesterol acyltransferase (LCAT) gene loci. RECENT FINDINGS It has been documented that apoA-I, myeloperoxidase and paraoxonase 1 (PON1) form a complex in HDL that is critical for HDL binding and function. Myeloperoxidase has a negative impact on HDL function, whereas PON1 has a beneficial effect. Patients who lack apoA-I develop markedly premature CHD. Patients who lack ATP-binding cassette transfer protein A1 transporter function have only very small discoidal preβ-1 HDL, and develop hepatosplenomegaly, intermittent neuropathy and premature CHD, although significant heterogeneity for these disorders has been reported. Patients with LCAT deficiency have abnormal small discoidal LDLs and HDL particles, and develop kidney failure. Enzyme replacement therapy is being developed for the latter disorder. SUMMARY Recent data indicates that proteins other than apoA-I and apoA-II such as MPO and PON1 have important effects on HDL function. There has been considerable recent progress made in our understanding of HDL protein content and function.
Collapse
Affiliation(s)
- Ernst J Schaefer
- Lipid Metabolism Section, Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, USA
| | | | | |
Collapse
|