1
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Hinton AO, N'jai AU, Vue Z, Wanjalla C. Connection Between HIV and Mitochondria in Cardiovascular Disease and Implications for Treatments. Circ Res 2024; 134:1581-1606. [PMID: 38781302 PMCID: PMC11122810 DOI: 10.1161/circresaha.124.324296] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
HIV infection and antiretroviral therapy alter mitochondrial function, which can progressively lead to mitochondrial damage and accelerated aging. The interaction between persistent HIV reservoirs and mitochondria may provide insight into the relatively high rates of cardiovascular disease and mortality in persons living with HIV. In this review, we explore the intricate relationship between HIV and mitochondrial function, highlighting the potential for novel therapeutic strategies in the context of cardiovascular diseases. We reflect on mitochondrial dynamics, mitochondrial DNA, and mitochondrial antiviral signaling protein in the context of HIV. Furthermore, we summarize how toxicities related to early antiretroviral therapy and current highly active antiretroviral therapy can contribute to mitochondrial dysregulation, chronic inflammation, and poor clinical outcomes. There is a need to understand the mechanisms and develop new targeted therapies. We further consider current and potential future therapies for HIV and their interplay with mitochondria. We reflect on the next-generation antiretroviral therapies and HIV cure due to the direct and indirect effects of HIV persistence, associated comorbidities, coinfections, and the advancement of interdisciplinary research fields. This includes exploring novel and creative approaches to target mitochondria for therapeutic intervention.
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Affiliation(s)
- Antentor O Hinton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN (A.O.H., Z.V.)
| | - Alhaji U N'jai
- Biological Sciences, Fourah Bay College and College of Medicine and Allied Health Sciences (COMAHS), University of Sierra Leone, Freetown, Sierra Leone and Koinadugu College, Kabala (A.U.N.)
| | - Zer Vue
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN (A.O.H., Z.V.)
| | - Celestine Wanjalla
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (C.W.)
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2
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Kim MJ, Simms S, Behnammanesh G, Honkura Y, Suzuki J, Park HJ, Milani M, Katori Y, Bird JE, Ikeda A, Someya S. A Mutation in Tmem135 Causes Progressive Sensorineural Hearing Loss. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.09.593414. [PMID: 38766120 PMCID: PMC11100813 DOI: 10.1101/2024.05.09.593414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Transmembrane protein 135 (TMEM135) is a 52 kDa protein with five predicted transmembrane domains that is highly conserved across species. Previous studies have shown that TMEM135 is involved in mitochondrial dynamics, thermogenesis, and lipid metabolism in multiple tissues; however, its role in the inner ear or the auditory system is unknown. We investigated the function of TMEM135 in hearing using wild-type (WT) and Tmem135 FUN025/FUN025 ( FUN025 ) mutant mice on a CBA/CaJ background, a normal-hearing mouse strain. Although FUN025 mice displayed normal auditory brainstem response (ABR) at 1 month, we observed significantly elevated ABR thresholds at 8, 16, and 64 kHz by 3 months, which progressed to profound hearing loss by 12 months. Consistent with our auditory testing, 13-month-old FUN025 mice exhibited a severe loss of outer hair cells and spiral ganglion neurons in the cochlea. Our results using BaseScope in situ hybridization indicate that TMEM135 is expressed in the inner hair cells, outer hair cells, and supporting cells. Together, these results demonstrate that the FUN025 mutation in Tmem135 causes progressive sensorineural hearing loss, and suggest that TMEM135 is crucial for maintaining key cochlear cell types and normal sensory function in the aging cochlea.
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3
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Liu J, Bao X, Huang J, Chen R, Tan Y, Zhang Z, Xiao B, Kong F, Gu C, Du J, Wang H, Qi J, Tan J, Ma D, Shi C, Xu G. TMEM135 maintains the equilibrium of osteogenesis and adipogenesis by regulating mitochondrial dynamics. Metabolism 2024; 152:155767. [PMID: 38154611 DOI: 10.1016/j.metabol.2023.155767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 12/10/2023] [Accepted: 12/20/2023] [Indexed: 12/30/2023]
Abstract
BACKGROUND Disturbance in the differentiation process of bone marrow mesenchymal stem cells (BMSCs) leads to osteoporosis. Mitochondrial dynamics plays a pivotal role in the metabolism and differentiation of BMSCs. However, the mechanisms underlying mitochondrial dynamics and their impact on the differentiation equilibrium of BMSCs remain unclear. METHODS We investigated the mitochondrial morphology and markers related to mitochondrial dynamics during BMSCs osteogenic and adipogenic differentiation. Bioinformatics was used to screen potential genes regulating BMSCs differentiation through mitochondrial dynamics. Subsequently, we evaluated the impact of Transmembrane protein 135 (TMEM135) deficiency on bone homeostasis by comparing Tmem135 knockout mice with their littermates. The mechanism of TMEM135 in mitochondrial dynamics and BMSCs differentiation was also investigated in vivo and in vitro. RESULTS Distinct changes in mitochondrial morphology were observed between osteogenic and adipogenic differentiation of BMSCs, manifesting as fission in the late stage of osteogenesis and fusion in adipogenesis. Additionally, we revealed that TMEM135, a modulator of mitochondrial dynamics, played a functional role in regulating the equilibrium between adipogenesis and osteogenesis. The TMEM135 deficiency impaired mitochondrial fission and disrupted crucial mitochondrial energy metabolism during osteogenesis. Tmem135 knockout mice showed osteoporotic phenotype, characterized by reduced osteogenesis and increased adipogenesis. Mechanistically, TMEM135 maintained intracellular calcium ion homeostasis and facilitated the dephosphorylation of dynamic-related protein 1 at Serine 637 in BMSCs. CONCLUSIONS Our findings underscore the significant role of TMEM135 as a modulator in orchestrating the differentiation trajectory of BMSCs and promoting a shift in mitochondrial dynamics toward fission. This ultimately contributes to the osteogenesis process. This work has provided promising biological targets for the treatment of osteoporosis.
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Affiliation(s)
- Jia Liu
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Xiaogang Bao
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Jian Huang
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Rukun Chen
- Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Yixuan Tan
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Zheng Zhang
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Bing Xiao
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Fanqi Kong
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Changjiang Gu
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Jianhang Du
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Haotian Wang
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Junqiang Qi
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China
| | - Junming Tan
- Department of Orthopedics, The 72nd Army Hospital of the People's Liberation Army, Huzhou 313099, PR China
| | - Duan Ma
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, PR China.
| | - Changgui Shi
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China.
| | - Guohua Xu
- Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai 200003, PR China.
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4
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Kumar R, Islinger M, Worthy H, Carmichael R, Schrader M. The peroxisome: an update on mysteries 3.0. Histochem Cell Biol 2024; 161:99-132. [PMID: 38244103 PMCID: PMC10822820 DOI: 10.1007/s00418-023-02259-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2023] [Indexed: 01/22/2024]
Abstract
Peroxisomes are highly dynamic, oxidative organelles with key metabolic functions in cellular lipid metabolism, such as the β-oxidation of fatty acids and the synthesis of myelin sheath lipids, as well as the regulation of cellular redox balance. Loss of peroxisomal functions causes severe metabolic disorders in humans. Furthermore, peroxisomes also fulfil protective roles in pathogen and viral defence and immunity, highlighting their wider significance in human health and disease. This has sparked increasing interest in peroxisome biology and their physiological functions. This review presents an update and a continuation of three previous review articles addressing the unsolved mysteries of this remarkable organelle. We continue to highlight recent discoveries, advancements, and trends in peroxisome research, and address novel findings on the metabolic functions of peroxisomes, their biogenesis, protein import, membrane dynamics and division, as well as on peroxisome-organelle membrane contact sites and organelle cooperation. Furthermore, recent insights into peroxisome organisation through super-resolution microscopy are discussed. Finally, we address new roles for peroxisomes in immune and defence mechanisms and in human disorders, and for peroxisomal functions in different cell/tissue types, in particular their contribution to organ-specific pathologies.
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Grants
- BB/W015420/1, BB/V018167/1, BB/T002255/1, BB/R016844/1 Biotechnology and Biological Sciences Research Council
- BB/W015420/1, BB/V018167/1, BB/T002255/1, BB/R016844/1 Biotechnology and Biological Sciences Research Council
- BB/W015420/1, BB/V018167/1, BB/T002255/1, BB/R016844/1 Biotechnology and Biological Sciences Research Council
- European Union’s Horizon 2020 research and innovation programme
- Deutsches Zentrum für Herz-Kreislaufforschung
- German Research Foundation
- Medical Faculty Mannheim, University of Heidelberg
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Affiliation(s)
- Rechal Kumar
- Faculty of Health and Life Sciences, Department of Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Markus Islinger
- Institute of Neuroanatomy, Medical Faculty Mannheim, Mannheim Centre for Translational Neuroscience, University of Heidelberg, 68167, Mannheim, Germany
| | - Harley Worthy
- Faculty of Health and Life Sciences, Department of Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Ruth Carmichael
- Faculty of Health and Life Sciences, Department of Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Michael Schrader
- Faculty of Health and Life Sciences, Department of Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
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5
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Landowski M, Gogoi P, Ikeda S, Ikeda A. Roles of transmembrane protein 135 in mitochondrial and peroxisomal functions - implications for age-related retinal disease. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1355379. [PMID: 38576540 PMCID: PMC10993500 DOI: 10.3389/fopht.2024.1355379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
Aging is the most significant risk factor for age-related diseases in general, which is true for age-related diseases in the eye including age-related macular degeneration (AMD). Therefore, in order to identify potential therapeutic targets for these diseases, it is crucial to understand the normal aging process and how its mis-regulation could cause age-related diseases at the molecular level. Recently, abnormal lipid metabolism has emerged as one major aspect of age-related symptoms in the retina. Animal models provide excellent means to identify and study factors that regulate lipid metabolism in relation to age-related symptoms. Central to this review is the role of transmembrane protein 135 (TMEM135) in the retina. TMEM135 was identified through the characterization of a mutant mouse strain exhibiting accelerated retinal aging and positional cloning of the responsible mutation within the gene, indicating the crucial role of TMEM135 in regulating the normal aging process in the retina. Over the past decade, the molecular functions of TMEM135 have been explored in various models and tissues, providing insights into the regulation of metabolism, particularly lipid metabolism, through its action in multiple organelles. Studies indicated that TMEM135 is a significant regulator of peroxisomes, mitochondria, and their interaction. Here, we provide an overview of the molecular functions of TMEM135 which is crucial for regulating mitochondria, peroxisomes, and lipids. The review also discusses the age-dependent phenotypes in mice with TMEM135 perturbations, emphasizing the importance of a balanced TMEM135 function for the health of the retina and other tissues including the heart, liver, and adipose tissue. Finally, we explore the potential roles of TMEM135 in human age-related retinal diseases, connecting its functions to the pathobiology of AMD.
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Affiliation(s)
- Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
| | - Purnima Gogoi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
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6
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Hu D, Tan M, Lu D, Kleiboeker B, Liu X, Park H, Kravitz AV, Shoghi KI, Tseng YH, Razani B, Ikeda A, Lodhi IJ. TMEM135 links peroxisomes to the regulation of brown fat mitochondrial fission and energy homeostasis. Nat Commun 2023; 14:6099. [PMID: 37773161 PMCID: PMC10541902 DOI: 10.1038/s41467-023-41849-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 09/20/2023] [Indexed: 10/01/2023] Open
Abstract
Mitochondrial morphology, which is controlled by mitochondrial fission and fusion, is an important regulator of the thermogenic capacity of brown adipocytes. Adipose-specific peroxisome deficiency impairs thermogenesis by inhibiting cold-induced mitochondrial fission due to decreased mitochondrial membrane content of the peroxisome-derived lipids called plasmalogens. Here, we identify TMEM135 as a critical mediator of the peroxisomal regulation of mitochondrial fission and thermogenesis. Adipose-specific TMEM135 knockout in mice blocks mitochondrial fission, impairs thermogenesis, and increases diet-induced obesity and insulin resistance. Conversely, TMEM135 overexpression promotes mitochondrial division, counteracts obesity and insulin resistance, and rescues thermogenesis in peroxisome-deficient mice. Mechanistically, thermogenic stimuli promote association between peroxisomes and mitochondria and plasmalogen-dependent localization of TMEM135 in mitochondria, where it mediates PKA-dependent phosphorylation and mitochondrial retention of the fission factor Drp1. Together, these results reveal a previously unrecognized inter-organelle communication regulating mitochondrial fission and energy homeostasis and identify TMEM135 as a potential target for therapeutic activation of BAT.
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Affiliation(s)
- Donghua Hu
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Min Tan
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Dongliang Lu
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Brian Kleiboeker
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Xuejing Liu
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Hongsuk Park
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Alexxai V Kravitz
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Kooresh I Shoghi
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Yu-Hua Tseng
- Section on Integrative Physiology and Metabolism, Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
| | - Babak Razani
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA, USA
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - Irfan J Lodhi
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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7
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Cho SJ, Pronko A, Yang J, Stout-Delgado H. Impact of Senolytic Treatment on Gene Expression in Aged Lung. Int J Mol Sci 2023; 24:7628. [PMID: 37108795 PMCID: PMC10145650 DOI: 10.3390/ijms24087628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/14/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Cellular senescence plays a key role in mediating tissue remodeling and modulation of host responses to pathogenic stimuli. Our current study was designed to gain a better understanding of the impact of short-term senolytic treatment or inflammatory stimulation on lung senescence. The results of our study demonstrate that short term treatment of aged adult mice (20 months of age) with senolytics, quercetin, and dasatinib decreases p16 and p21 expression in lung tissue. Short-term treatment with senolytics also significantly improved the expression of genes associated with genomic instability, telomere attrition, mitochondrial dysfunction, DNA binding, and the inflammatory response. In contrast, in response to low-dose LPS administration, there was increased expression of genes associated with genomic instability, mitochondrial dysfunction, and heightened inflammatory responses in young adult murine lung (3 months of age). Taken together, the results of our current study illustrate the efficacy of senolytic treatment on modulating responses in aged lung and the potential role of chronic low dose inflammation on senescence induction in the lung.
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Affiliation(s)
| | | | | | - Heather Stout-Delgado
- Pulmonary and Critical Medicine, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
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8
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Erdogmus S, Concepcion AR, Yamashita M, Sidhu I, Tao AY, Li W, Rocha PP, Huang B, Garippa R, Lee B, Lee A, Hell JW, Lewis RS, Prakriya M, Feske S. Cavβ1 regulates T cell expansion and apoptosis independently of voltage-gated Ca 2+ channel function. Nat Commun 2022; 13:2033. [PMID: 35440113 PMCID: PMC9018955 DOI: 10.1038/s41467-022-29725-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 03/22/2022] [Indexed: 12/11/2022] Open
Abstract
TCR stimulation triggers Ca2+ signals that are critical for T cell function and immunity. Several pore-forming α and auxiliary β subunits of voltage-gated Ca2+ channels (VGCC) were reported in T cells, but their mechanism of activation remains elusive and their contribution to Ca2+ signaling in T cells is controversial. We here identify CaVβ1, encoded by Cacnb1, as a regulator of T cell function. Cacnb1 deletion enhances apoptosis and impairs the clonal expansion of T cells after lymphocytic choriomeningitis virus (LCMV) infection. By contrast, Cacnb1 is dispensable for T cell proliferation, cytokine production and Ca2+ signaling. Using patch clamp electrophysiology and Ca2+ recordings, we are unable to detect voltage-gated Ca2+ currents or Ca2+ influx in human and mouse T cells upon depolarization with or without prior TCR stimulation. mRNAs of several VGCC α1 subunits are detectable in human (CaV3.3, CaV3.2) and mouse (CaV2.1) T cells, but they lack transcription of many 5' exons, likely resulting in N-terminally truncated and non-functional proteins. Our findings demonstrate that although CaVβ1 regulates T cell function, these effects are independent of VGCC channel activity.
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Affiliation(s)
- Serap Erdogmus
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Axel R Concepcion
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Megumi Yamashita
- Department of Pharmacology, Northwestern University, Chicago, IL, USA
| | - Ikjot Sidhu
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Anthony Y Tao
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Wenyi Li
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Pedro P Rocha
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- National Cancer Institute, NIH, Bethesda, MD, USA
| | - Bonnie Huang
- National Institute of Allergy and Infectious Disease, Bethesda, MD, USA
- National Human Genome Research Institute, Bethesda, MD, USA
| | - Ralph Garippa
- Department of Cancer Biology & Genetics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Boram Lee
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Amy Lee
- Department of Neuroscience, University of Texas-Austin, Austin, TX, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Richard S Lewis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
| | - Murali Prakriya
- Department of Pharmacology, Northwestern University, Chicago, IL, USA.
| | - Stefan Feske
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA.
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9
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Landowski M, Bhute VJ, Takimoto T, Grindel S, Shahi PK, Pattnaik BR, Ikeda S, Ikeda A. A mutation in transmembrane protein 135 impairs lipid metabolism in mouse eyecups. Sci Rep 2022; 12:756. [PMID: 35031662 PMCID: PMC8760256 DOI: 10.1038/s41598-021-04644-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/28/2021] [Indexed: 12/13/2022] Open
Abstract
Aging is a significant factor in the development of age-related diseases but how aging disrupts cellular homeostasis to cause age-related retinal disease is unknown. Here, we further our studies on transmembrane protein 135 (Tmem135), a gene involved in retinal aging, by examining the transcriptomic profiles of wild-type, heterozygous and homozygous Tmem135 mutant posterior eyecup samples through RNA sequencing (RNA-Seq). We found significant gene expression changes in both heterozygous and homozygous Tmem135 mutant mouse eyecups that correlate with visual function deficits. Further analysis revealed that expression of many genes involved in lipid metabolism are changed due to the Tmem135 mutation. Consistent with these changes, we found increased lipid accumulation in mutant Tmem135 eyecup samples. Since mutant Tmem135 mice have similar ocular pathologies as human age-related macular degeneration (AMD) eyes, we compared our homozygous Tmem135 mutant eyecup RNA-Seq dataset with transcriptomic datasets of human AMD donor eyes. We found similar changes in genes involved in lipid metabolism between the homozygous Tmem135 mutant eyecups and AMD donor eyes. Our study suggests that the Tmem135 mutation affects lipid metabolism as similarly observed in human AMD eyes, thus Tmem135 mutant mice can serve as a good model for the role of dysregulated lipid metabolism in AMD.
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Affiliation(s)
- Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Vijesh J Bhute
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- Department of Chemical Engineering, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Tetsuya Takimoto
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - Samuel Grindel
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - Pawan K Shahi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Bikash R Pattnaik
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA.
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA.
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10
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Beasley HK, Rodman TA, Collins GV, Hinton A, Exil V. TMEM135 is a Novel Regulator of Mitochondrial Dynamics and Physiology with Implications for Human Health Conditions. Cells 2021; 10:cells10071750. [PMID: 34359920 PMCID: PMC8303332 DOI: 10.3390/cells10071750] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 12/16/2022] Open
Abstract
Transmembrane proteins (TMEMs) are integral proteins that span biological membranes. TMEMs function as cellular membrane gates by modifying their conformation to control the influx and efflux of signals and molecules. TMEMs also reside in and interact with the membranes of various intracellular organelles. Despite much knowledge about the biological importance of TMEMs, their role in metabolic regulation is poorly understood. This review highlights the role of a single TMEM, transmembrane protein 135 (TMEM135). TMEM135 is thought to regulate the balance between mitochondrial fusion and fission and plays a role in regulating lipid droplet formation/tethering, fatty acid metabolism, and peroxisomal function. This review highlights our current understanding of the various roles of TMEM135 in cellular processes, organelle function, calcium dynamics, and metabolism.
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Affiliation(s)
- Heather K. Beasley
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (H.K.B.); (T.A.R.)
| | - Taylor A. Rodman
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (H.K.B.); (T.A.R.)
| | - Greg V. Collins
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, IA 52242, USA;
- Department of Pediatrics-Cardiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Antentor Hinton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (H.K.B.); (T.A.R.)
- Correspondence: (A.H.J.); (V.E.)
| | - Vernat Exil
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, IA 52242, USA;
- Department of Pediatrics-Cardiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
- Correspondence: (A.H.J.); (V.E.)
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11
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Muench NA, Patel S, Maes ME, Donahue RJ, Ikeda A, Nickells RW. The Influence of Mitochondrial Dynamics and Function on Retinal Ganglion Cell Susceptibility in Optic Nerve Disease. Cells 2021; 10:cells10071593. [PMID: 34201955 PMCID: PMC8306483 DOI: 10.3390/cells10071593] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/30/2022] Open
Abstract
The important roles of mitochondrial function and dysfunction in the process of neurodegeneration are widely acknowledged. Retinal ganglion cells (RGCs) appear to be a highly vulnerable neuronal cell type in the central nervous system with respect to mitochondrial dysfunction but the actual reasons for this are still incompletely understood. These cells have a unique circumstance where unmyelinated axons must bend nearly 90° to exit the eye and then cross a translaminar pressure gradient before becoming myelinated in the optic nerve. This region, the optic nerve head, contains some of the highest density of mitochondria present in these cells. Glaucoma represents a perfect storm of events occurring at this location, with a combination of changes in the translaminar pressure gradient and reassignment of the metabolic support functions of supporting glia, which appears to apply increased metabolic stress to the RGC axons leading to a failure of axonal transport mechanisms. However, RGCs themselves are also extremely sensitive to genetic mutations, particularly in genes affecting mitochondrial dynamics and mitochondrial clearance. These mutations, which systemically affect the mitochondria in every cell, often lead to an optic neuropathy as the sole pathologic defect in affected patients. This review summarizes knowledge of mitochondrial structure and function, the known energy demands of neurons in general, and places these in the context of normal and pathological characteristics of mitochondria attributed to RGCs.
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Affiliation(s)
- Nicole A. Muench
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA; (N.A.M.); (S.P.); (R.J.D.)
| | - Sonia Patel
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA; (N.A.M.); (S.P.); (R.J.D.)
| | - Margaret E. Maes
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria;
| | - Ryan J. Donahue
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA; (N.A.M.); (S.P.); (R.J.D.)
- Boston Children’s Hospital, Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA;
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Robert W. Nickells
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA; (N.A.M.); (S.P.); (R.J.D.)
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
- Correspondence:
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Landowski M, Grindel S, Shahi PK, Johnson A, Western D, Race A, Shi F, Benson J, Gao M, Santoirre E, Lee WH, Ikeda S, Pattnaik BR, Ikeda A. Modulation of Tmem135 Leads to Retinal Pigmented Epithelium Pathologies in Mice. Invest Ophthalmol Vis Sci 2020; 61:16. [PMID: 33064130 PMCID: PMC7581492 DOI: 10.1167/iovs.61.12.16] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/23/2020] [Indexed: 12/12/2022] Open
Abstract
Purpose Aging is a critical risk factor for the development of retinal diseases, but how aging perturbs ocular homeostasis and contributes to disease is unknown. We identified transmembrane protein 135 (Tmem135) as a gene important for regulating retinal aging and mitochondrial dynamics in mice. Overexpression of Tmem135 causes mitochondrial fragmentation and pathologies in the hearts of mice. In this study, we examine the eyes of mice overexpressing wild-type Tmem135 (Tmem135 TG) and compare their phenotype to Tmem135 mutant mice. Methods Eyes were collected for histology, immunohistochemistry, electron microscopy, quantitative PCR, and Western blot analysis. Before tissue collection, electroretinography (ERG) was performed to assess visual function. Mouse retinal pigmented epithelium (RPE) cultures were established to visualize mitochondria. Results Pathologies were observed only in the RPE of Tmem135 TG mice, including degeneration, migratory cells, vacuolization, dysmorphogenesis, cell enlargement, and basal laminar deposit formation despite similar augmented levels of Tmem135 in the eyecup (RPE/choroid/sclera) and neural retina. We observed reduced mitochondria number and size in the Tmem135 TG RPE. ERG amplitudes were decreased in 365-day-old mice overexpressing Tmem135 that correlated with reduced expression of RPE cell markers. In Tmem135 mutant mice, RPE cells are thicker, smaller, and denser than their littermate controls without any signs of degeneration. Conclusions Overexpression and mutation of Tmem135 cause contrasting RPE abnormalities in mice that correlate with changes in mitochondrial shape and size (overfragmented in TG vs. overfused in mutant). We conclude proper regulation of mitochondrial homeostasis by TMEM135 is critical for RPE health.
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Affiliation(s)
- Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
- Department of Pediatrics, Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Samuel Grindel
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Pawan K. Shahi
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
- Department of Pediatrics, Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Abigail Johnson
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Daniel Western
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Adrienne Race
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Franky Shi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Jonathan Benson
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Marvin Gao
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Evelyn Santoirre
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Wei-Hua Lee
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Bikash R. Pattnaik
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
- Department of Pediatrics, Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
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Lee WH, Bhute VJ, Higuchi H, Ikeda S, Palecek SP, Ikeda A. Metabolic alterations caused by the mutation and overexpression of the Tmem135 gene. Exp Biol Med (Maywood) 2020; 245:1571-1583. [PMID: 32515224 DOI: 10.1177/1535370220932856] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
IMPACT STATEMENT Mitochondria are dynamic organelles undergoing fission and fusion. Proper regulation of this process is important for healthy aging process, as aberrant mitochondrial dynamics are associated with several age-related diseases/pathologies. However, it is not well understood how imbalanced mitochondrial dynamics may lead to those diseases and pathologies. Here, we aimed to determine metabolic alterations in tissues and cells from mouse models with over-fused (fusion > fission) and over-fragmented (fusion < fission) mitochondria that display age-related disease pathologies. Our results indicated tissue-dependent sensitivity to these mitochondrial changes, and metabolic pathways likely affected by aberrant mitochondrial dynamics. This study provides new insights into how dysregulated mitochondrial dynamics could lead to functional abnormalities of tissues and cells.
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Affiliation(s)
- Wei-Hua Lee
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Vijesh J Bhute
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Hitoshi Higuchi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
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Veloso CD, Belew GD, Ferreira LL, Grilo LF, Jones JG, Portincasa P, Sardão VA, Oliveira PJ. A Mitochondrial Approach to Cardiovascular Risk and Disease. Curr Pharm Des 2020; 25:3175-3194. [PMID: 31470786 DOI: 10.2174/1389203720666190830163735] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 08/24/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Cardiovascular diseases (CVDs) are a leading risk factor for mortality worldwide and the number of CVDs victims is predicted to rise through 2030. While several external parameters (genetic, behavioral, environmental and physiological) contribute to cardiovascular morbidity and mortality; intrinsic metabolic and functional determinants such as insulin resistance, hyperglycemia, inflammation, high blood pressure and dyslipidemia are considered to be dominant factors. METHODS Pubmed searches were performed using different keywords related with mitochondria and cardiovascular disease and risk. In vitro, animal and human results were extracted from the hits obtained. RESULTS High cardiac energy demand is sustained by mitochondrial ATP production, and abnormal mitochondrial function has been associated with several lifestyle- and aging-related pathologies in the developed world such as diabetes, non-alcoholic fatty liver disease (NAFLD) and kidney diseases, that in turn can lead to cardiac injury. In order to delay cardiac mitochondrial dysfunction in the context of cardiovascular risk, regular physical activity has been shown to improve mitochondrial parameters and myocardial tolerance to ischemia-reperfusion (IR). Furthermore, pharmacological interventions can prevent the risk of CVDs. Therapeutic agents that can target mitochondria, decreasing ROS production and improve its function have been intensively researched. One example is the mitochondria-targeted antioxidant MitoQ10, which already showed beneficial effects in hypertensive rat models. Carvedilol or antidiabetic drugs also showed protective effects by preventing cardiac mitochondrial oxidative damage. CONCLUSION This review highlights the role of mitochondrial dysfunction in CVDs, also show-casing several approaches that act by improving mitochondrial function in the heart, contributing to decrease some of the risk factors associated with CVDs.
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Affiliation(s)
- Caroline D Veloso
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - Getachew D Belew
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - Luciana L Ferreira
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - Luís F Grilo
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - John G Jones
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - Piero Portincasa
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro" Medical School, Bari, Italy
| | - Vilma A Sardão
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
| | - Paulo J Oliveira
- CNC-Center for Neuroscience and Cell Biology, UC-Biotech, University of Coimbra, Biocant Park, Cantanhede, Portugal
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Dorotea D, Koya D, Ha H. Recent Insights Into SREBP as a Direct Mediator of Kidney Fibrosis via Lipid-Independent Pathways. Front Pharmacol 2020; 11:265. [PMID: 32256356 PMCID: PMC7092724 DOI: 10.3389/fphar.2020.00265] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/24/2020] [Indexed: 12/17/2022] Open
Abstract
Sterol regulatory-element binding proteins (SREBPs) are classical regulators of cellular lipid metabolism in the kidney and other tissues. SREBPs are currently recognized as versatile transcription factors involved in a myriad of cellular processes. Meanwhile, SREBPs have been recognized to mediate lipotoxicity, contributing to the progression of kidney diseases. SREBP1 has been shown to bind to the promoter region of TGFβ, a major pro-fibrotic signaling mechanism in the kidney. Conversely, TGFβ activates SREBP1 transcriptional activity suggesting a positive feedback loop of SREBP1 in TGFβ signaling. Public ChIP-seq data revealed numerous non-lipid transcriptional targets of SREBPs that plausibly play roles in progressive kidney disease and fibrosis. This review provides new insights into SREBP as a mediator of kidney fibrosis via lipid-independent pathways.
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Affiliation(s)
- Debra Dorotea
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans University, Seoul, South Korea
| | - Daisuke Koya
- Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan
| | - Hunjoo Ha
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans University, Seoul, South Korea
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Mitophagy, Mitochondrial Dynamics, and Homeostasis in Cardiovascular Aging. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:9825061. [PMID: 31781358 PMCID: PMC6875274 DOI: 10.1155/2019/9825061] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 09/13/2019] [Indexed: 12/19/2022]
Abstract
Biological aging is an inevitable and independent risk factor for a wide array of chronic diseases including cardiovascular and metabolic diseases. Ample evidence has established a pivotal role for interrupted mitochondrial homeostasis in the onset and development of aging-related cardiovascular anomalies. A number of culprit factors have been suggested in aging-associated mitochondrial anomalies including oxidative stress, lipid toxicity, telomere shortening, metabolic disturbance, and DNA damage, with recent findings revealing a likely role for compromised mitochondrial dynamics and mitochondrial quality control machinery such as autophagy. Mitochondria undergo consistent fusion and fission, which are crucial for mitochondrial homeostasis and energy adaptation. Autophagy, in particular, mitochondria-selective autophagy, namely, mitophagy, refers to a highly conservative cellular process to degrade and clear long-lived or damaged cellular organelles including mitochondria, the function of which gradually deteriorates with increased age. Mitochondrial homeostasis could be achieved through a cascade of independent but closely related processes including fusion, fission, mitophagy, and mitochondrial biogenesis. With improved health care and increased human longevity, the ever-rising aging society has imposed a high cardiovascular disease prevalence. It is thus imperative to understand the role of mitochondrial homeostasis in the regulation of lifespan and healthspan. Targeting mitochondrial homeostasis should offer promising novel therapeutic strategies against aging-related complications, particularly cardiovascular diseases.
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Optical Metabolic Imaging for Assessment of Radiation-Induced Injury to Rat Kidney and Mitigation by Lisinopril. Ann Biomed Eng 2019; 47:1564-1574. [PMID: 30963380 DOI: 10.1007/s10439-019-02255-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/26/2019] [Indexed: 12/17/2022]
Abstract
The kidney is one of the most radiosensitive organs; it is the primary dose-limiting organ in radiotherapies for upper abdominal cancers. The role of mitochondrial redox state in the development and treatment of renal radiation injury, however, remains ill-defined. This study utilizes 3D optical cryo-imaging to quantify renal mitochondrial bioenergetics dysfunction after 13 Gy leg-out partial body irradiation (PBI). Furthermore, the mitigating effects of lisinopril (lisino), an anti-hypertensive angiotensin converting enzyme inhibitor, is assessed in renal radiation-induced injuries. Around day 150 post-irradiation, kidneys are harvested for cryo-imaging. The 3D images of the metabolic indices (NADH, nicotinamide adenine dinucleotide, and FAD, flavin adenine dinucleotide) are acquired, and the mitochondrial redox states of the irradiated and irradiated + lisino kidneys are quantified by calculating the volumetric mean redox ratio (NADH/FAD). PBI oxidized renal mitochondrial redox state by 78%. The kidneys from the irradiated + lisino rats showed mitigation of mitochondrial redox state by 93% compared to the PBI group. The study provides evidence for an altered bioenergetics and energy metabolism in the rat model of irradiation-induced kidney damage. In addition, the results suggest that lisinopril mitigates irradiation damage by attenuating the oxidation of mitochondria leading to increase redox ratio.
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