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Li K, Cao JF, Gong Y, Xiong L, Wu M, Qi Y, Ying X, Liu D, Ma X, Zhang X. Rapamycin improves the survival of epilepsy model cells by blocking phosphorylation of mTOR base on computer simulations and cellular experiments. Neurochem Int 2024; 176:105746. [PMID: 38641027 DOI: 10.1016/j.neuint.2024.105746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/08/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
PURPOSE Epilepsy is a chronic brain dysfunction characterized by recurrent epileptic seizures. Rapamycin is a naturally occurring macrolide from Streptomyces hygroscopicus, and rapamycin may provide a protective effect on the nervous system by affecting mTOR. Therefore, we investigated the pharmacologic mechanism of rapamycin treating epilepsy through bioinformatics analysis, cellular experiments and supercomputer simulation. METHODS Bioinformatics analysis was used to analyze targets of rapamycin treating epilepsy. We established epilepsy cell model by HT22 cells. RT-qPCR, WB and IF were used to verify the effects of rapamycin on mTOR at gene level and protein level. Computer simulations were used to model and evaluate the stability of rapamycin binding to mTOR protein. RESULTS Bioinformatics indicated mTOR played an essential role in signaling pathways of cell growth and cell metabolism. Cellular experiments showed that rapamycin could promote cell survival, and rapamycin did not have an effect on mRNA expression of mTOR. However, rapamycin was able to significantly inhibit the phosphorylation of mTOR at protein level. Computer simulations indicated that rapamycin was involved in the treatment of epilepsy through regulating phosphorylation of mTOR at protein level. CONCLUSION We found that rapamycin was capable of promoting the survival of epilepsy cells by inhibiting the phosphorylation of mTOR at protein level, and rapamycin did not have an effect on mRNA expression of mTOR. In addition to the traditional study that rapamycin affects mTORC1 complex by acting on FKBP12, this study found rapamycin could also directly block the phosphorylation of mTOR, therefore affecting the assembly of mTORC1 complex and mTOR signaling pathway.
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Affiliation(s)
- Kezhou Li
- College of Medicine, Southwest Jiaotong University, Chengdu, China; Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu, China
| | - Jun-Feng Cao
- Chengdu Medical College, Chengdu, China; College of Medicine, Southwest Jiaotong University, Chengdu, China
| | | | - Li Xiong
- Chengdu Medical College, Chengdu, China
| | - Mei Wu
- Chengdu Medical College, Chengdu, China
| | - Yue Qi
- Chengdu Medical College, Chengdu, China
| | | | | | - Xuntai Ma
- Chengdu Medical College, Chengdu, China; The First Affiliated Hospital of Clinical Medical College of Chengdu Medical College, Chengdu, China.
| | - Xiao Zhang
- Chengdu Medical College, Chengdu, China.
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Bhat MA, Dhaneshwar S. Neurodegenerative Diseases: New Hopes and Perspectives. Curr Mol Med 2024; 24:1004-1032. [PMID: 37691199 DOI: 10.2174/1566524023666230907093451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/10/2023] [Accepted: 07/27/2023] [Indexed: 09/12/2023]
Abstract
Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, Huntington's disease, and Friedrich ataxia are all incurable neurodegenerative diseases defined by the continuous progressive loss of distinct neuronal subtypes. Despite their rising prevalence among the world's ageing population, fewer advances have been made in the concurrent massive efforts to develop newer drugs. Recently, there has been a shift in research focus towards the discovery of new therapeutic agents for neurodegenerative diseases. In this review, we have summarized the recently developed therapies and their status in the management of neurodegenerative diseases.
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Affiliation(s)
- Mohammad Aadil Bhat
- Amity Institute of Pharmacy, Lucknow, Amity University Uttar Pradesh, Noida, UP, India
| | - Suneela Dhaneshwar
- Amity Institute of Pharmacy, Amity University Maharashtra, Mumbai, Maharashtra, India
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Czornobil R, Abou-Assali O, Remily-Wood E, Lynch DR, Noujaim SF, Chidipi B. The Cardiac Calcium Handling Machinery is Remodeled in Friedreich's Ataxia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.09.566141. [PMID: 38014032 PMCID: PMC10680642 DOI: 10.1101/2023.11.09.566141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Background Friedreich's ataxia (FA) is an inherited neurodegenerative disorder that causes progressive nervous system damage resulting in impaired muscle coordination. FA is the most common autosomal recessive form of ataxia and is caused by an expansion of the DNA triplet guanine-adenine-adenine (GAA) in the first intron of the Frataxin gene (FXN), located on chromosome 9q13. In the unaffected population, the number of GAA repeats ranges from 6 to 27 repetitions. In FA patients, GAA repeat expansions range from 44 to 1,700 repeats which decreases frataxin protein expression. Frataxin is a mitochondrial protein essential for various cellular functions, including iron metabolism. Reduced frataxin expression is thought to negatively affect mitochondrial iron metabolism, leading to increased oxidative damage. Although FA is considered a neurodegenerative disorder, FA patients display heart disease that includes hypertrophy, heart failure, arrhythmias, conduction abnormalities, and cardiac fibrosis. Objective In this work, we investigated whether abnormal Ca 2+ handling machinery is the molecular mechanism that perpetuates cardiac dysfunction in FA. Methods We used the frataxin knock-out (FXN-KO) mouse model of FA as well as human heart samples from donors with FA and from unaffected donors. ECG and echocardiography were used to assess cardiac function in the mice. Expression of calcium handling machinery proteins was assessed with proteomics and western blot. In left ventricular myocytes from FXN-KO and FXN-WT mice, the IonOptix system was used for calcium imaging, the seahorse assay was utilized to measure oxygen consumption rate (OCR), and confocal imaging was used to quantify the mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS). Results We found that major contractile proteins, including SERCA2a and Ryr2, were downregulated in human left ventricular samples from deceased donors with FA compared to unaffected donors, similar to the downregulation of these proteins in the left ventricular tissue from FXN-KO compared to FXN-WT. On the ECG, the RR, PR, QRS, and QTc were significantly longer in the FXN-KO mice compared to FXN-WT. The ejection fraction and fractional shortening were significantly decreased and left ventricular wall thickness and diameter were significantly increased in the FXN-KO mice versus FXN-WT. The mitochondrial membrane potential Δψm was depolarized, ROS levels were elevated, and OCR was decreased in ventricular myocytes from FXN-KO versus FXN-WT. Conclusion The development of left ventricular contractile dysfunction in FA is associated with reduced expression of calcium handling proteins and mitochondrial dysfunction.
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Hassan F, Khan AU, Zaidi SZUH, Niazi MK, ismail MA. In Vitro Antioxidant and Inhibitory Study of Picrorhiza kurroa (Kutki), Syzygium aromaticum (Loung), Lawsonia inermis (Henna), Rheum emodi (Revand Chini), Curcuma longa (Haldi) Against Lipid Per-Oxidation in Mice Brain and Liver. Dose Response 2023; 21:15593258231210431. [PMID: 37900620 PMCID: PMC10605699 DOI: 10.1177/15593258231210431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 10/11/2023] [Indexed: 10/31/2023] Open
Abstract
The aerobic organisms not only need oxygen for survival, but oxygen is also fundamentally malignant to the aerobic organism on the grounds of free radical generation and their affiliation with free oxidative stress. This study was done to evaluate the antioxidant and protective properties of P kurroa, S aromaticum, L inermis, R emodi, and C longa against lipid peroxidation induced by different pro-oxidants. The aqueous extracts of these medicinal plants showed inhibition against thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants (10 mM FeSO4 and 5 mM sodium nitroprusside) in the brain and liver of mice. Moreover, the free radical scavenging activities of the extracts were evaluated by the scavenging of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. L inermis, S aromaticum, and R emodi showed higher inhibitory effects, which could be attributed to their significantly reduced ability and free radical scavenging activities. Therefore, the oxidative stress in the brain and liver could be potentially managed or prevented by the dietary intake of L inermis, S aromaticum, and R emodi plants, which justifies the use of these plants in various degenerative diseases. C longa and P kurroa showed relatively weak antioxidant activities.
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Affiliation(s)
| | - Asmat Ullah Khan
- Department of Eastern Medicine, Faculty of Medical and Health Sciences, University of Poonch, Rawalakot, Pakistan
| | | | - Madiha Khan Niazi
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Lahore, Pakistan
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Rodrigues AV, Batelu S, Hinton TV, Rotondo J, Thompson L, Brunzelle JS, Stemmler TL. Drosophila melanogaster frataxin: protein crystal and predicted solution structure with identification of the iron-binding regions. Acta Crystallogr D Struct Biol 2023; 79:22-30. [PMID: 36601804 PMCID: PMC9815096 DOI: 10.1107/s2059798322011639] [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: 09/07/2022] [Accepted: 12/03/2022] [Indexed: 12/24/2022] Open
Abstract
Friedreich's ataxia (FRDA) is a hereditary cardiodegenerative and neurodegenerative disease that affects 1 in 50 000 Americans. FRDA arises from either a cellular inability to produce sufficient quantities or the production of a nonfunctional form of the protein frataxin, a key molecule associated with mitochondrial iron-sulfur cluster biosynthesis. Within the mitochondrial iron-sulfur cluster (ISC) assembly pathway, frataxin serves as an allosteric regulator for cysteine desulfurase, the enzyme that provides sulfur for [2Fe-2S] cluster assembly. Frataxin is a known iron-binding protein and is also linked to the delivery of ferrous ions to the scaffold protein, the ISC molecule responsible for the direct assembly of [2Fe-2S] clusters. The goal of this report is to provide structural details of the Drosophila melanogaster frataxin ortholog (Dfh), using both X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy, in order to provide the foundational insight needed to understand the structure-function correlation of the protein. Additionally, NMR iron(II) titrations were used to provide metal contacts on the protein to better understand how it binds iron and aids its delivery to the ISC scaffold protein. Here, the structural and functional similarities of Dfh to its orthologs are also outlined. Structural data show that bacterial, yeast, human and Drosophila frataxins are structurally similar, apart from a structured C-terminus in Dfh that is likely to aid in protein stability. The iron-binding location on helix 1 and strand 1 of Dfh is also conserved across orthologs.
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Affiliation(s)
- Andria V Rodrigues
- Department of Biochemistry and Molecular Biology, Wayne State University, Detroit, Michigan, USA
| | - Sharon Batelu
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan, USA
| | - Tiara V Hinton
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan, USA
| | - John Rotondo
- Department of Biochemistry and Molecular Biology, Wayne State University, Detroit, Michigan, USA
| | - Lindsey Thompson
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan, USA
| | - Joseph S Brunzelle
- Northwestern Synchrotron Research Centers, Life Science Collaborative Access Team, Northwestern University, Evanston, Illinois, USA
| | - Timothy L Stemmler
- Department of Biochemistry and Molecular Biology, Wayne State University, Detroit, Michigan, USA
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Fang X, Ardehali H, Min J, Wang F. The molecular and metabolic landscape of iron and ferroptosis in cardiovascular disease. Nat Rev Cardiol 2023; 20:7-23. [PMID: 35788564 PMCID: PMC9252571 DOI: 10.1038/s41569-022-00735-4] [Citation(s) in RCA: 297] [Impact Index Per Article: 297.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/30/2022] [Indexed: 02/08/2023]
Abstract
The maintenance of iron homeostasis is essential for proper cardiac function. A growing body of evidence suggests that iron imbalance is the common denominator in many subtypes of cardiovascular disease. In the past 10 years, ferroptosis, an iron-dependent form of regulated cell death, has become increasingly recognized as an important process that mediates the pathogenesis and progression of numerous cardiovascular diseases, including atherosclerosis, drug-induced heart failure, myocardial ischaemia-reperfusion injury, sepsis-induced cardiomyopathy, arrhythmia and diabetic cardiomyopathy. Therefore, a thorough understanding of the mechanisms involved in the regulation of iron metabolism and ferroptosis in cardiomyocytes might lead to improvements in disease management. In this Review, we summarize the relationship between the metabolic and molecular pathways of iron signalling and ferroptosis in the context of cardiovascular disease. We also discuss the potential targets of ferroptosis in the treatment of cardiovascular disease and describe the current limitations and future directions of these novel treatment targets.
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Affiliation(s)
- Xuexian Fang
- grid.410595.c0000 0001 2230 9154Department of Nutrition and Toxicology, School of Public Health, State Key Laboratory of Experimental Hematology, Hangzhou Normal University, Hangzhou, China ,grid.13402.340000 0004 1759 700XThe Fourth Affiliated Hospital, The First Affiliated Hospital, Institute of Translational Medicine, School of Public Health, Cancer Center, State Key Laboratory of Experimental Hematology, Zhejiang University School of Medicine, Hangzhou, China ,grid.412017.10000 0001 0266 8918The First Affiliated Hospital, The Second Affiliated Hospital, Basic Medical Sciences, School of Public Health, Hengyang Medical School, University of South China, Hengyang, China
| | - Hossein Ardehali
- grid.16753.360000 0001 2299 3507Feinberg Cardiovascular and Renal Research Institute, Northwestern University, Chicago, IL USA
| | - Junxia Min
- The Fourth Affiliated Hospital, The First Affiliated Hospital, Institute of Translational Medicine, School of Public Health, Cancer Center, State Key Laboratory of Experimental Hematology, Zhejiang University School of Medicine, Hangzhou, China.
| | - Fudi Wang
- The Fourth Affiliated Hospital, The First Affiliated Hospital, Institute of Translational Medicine, School of Public Health, Cancer Center, State Key Laboratory of Experimental Hematology, Zhejiang University School of Medicine, Hangzhou, China. .,The First Affiliated Hospital, The Second Affiliated Hospital, Basic Medical Sciences, School of Public Health, Hengyang Medical School, University of South China, Hengyang, China.
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Izzo C, Vitillo P, Di Pietro P, Visco V, Strianese A, Virtuoso N, Ciccarelli M, Galasso G, Carrizzo A, Vecchione C. The Role of Oxidative Stress in Cardiovascular Aging and Cardiovascular Diseases. Life (Basel) 2021; 11:60. [PMID: 33467601 PMCID: PMC7829951 DOI: 10.3390/life11010060] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/12/2022] Open
Abstract
Aging can be seen as process characterized by accumulation of oxidative stress induced damage. Oxidative stress derives from different endogenous and exogenous processes, all of which ultimately lead to progressive loss in tissue and organ structure and functions. The oxidative stress theory of aging expresses itself in age-related diseases. Aging is in fact a primary risk factor for many diseases and in particular for cardiovascular diseases and its derived morbidity and mortality. Here we highlight the role of oxidative stress in age-related cardiovascular aging and diseases. We take into consideration the molecular mechanisms, the structural and functional alterations, and the diseases accompanied to the cardiovascular aging process.
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Affiliation(s)
- Carmine Izzo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Paolo Vitillo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Paola Di Pietro
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Valeria Visco
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Andrea Strianese
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Nicola Virtuoso
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Michele Ciccarelli
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Gennaro Galasso
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Albino Carrizzo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
- Department of Angio-Cardio-Neurology, Vascular Physiopathology Unit, IRCCS Neuromed, 86077 Pozzilli, Isernia, Italy
| | - Carmine Vecchione
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
- Department of Angio-Cardio-Neurology, Vascular Physiopathology Unit, IRCCS Neuromed, 86077 Pozzilli, Isernia, Italy
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Hojati Z, Omidi F, Dehbashi M, Mohammad Soltani B. The Highlighted Roles of Metabolic and Cellular Response to Stress Pathways Engaged in Circulating hsa-miR-494-3p and hsa-miR-661 in Alzheimer's Disease. IRANIAN BIOMEDICAL JOURNAL 2020; 25:62-7. [PMID: 33129241 PMCID: PMC7748118 DOI: 10.29252/ibj.25.1.62] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Among different roles of miRNAs in AD pathogenesis, hsa-miR-494-3p and hsa-miR-661 functions are poorly understood. Methods: To obtain the gene targets, gene networks, gene ontology, and enrichment analysis of the two miRNAs, some web servers were utilized. Furthermore, the expressions of these miRNAs were analyzed by qRT-PCR in 36 blood sera, including 18 Alzheimer’s patients and 18 healthy individuals. Results: The in silico analysis demonstrated the highlighted roles of metabolic and cellular response to stress pathways engaged in circulating hsa-miR-494-3p and hsa-miR-661 in AD. The qRT-PCR analysis showed that the downregulated expression level of hsa-miR-661 was statistically significant (p < 0.05). Also, the ROC curve of hsa-miR-661 displayed the significant AUC (p = 0.01). Conclusion: Based on our findings, the metabolic and cellular responses to stress pathways are closely connected to these two miRNAs functions. Besides, the qRT-PCR and Roc curve determined hsa-miR-661 could be as a biomarker for diagnosis or prognosis of AD patients.
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Affiliation(s)
- Zohreh Hojati
- Division of Genetics, Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan 8174673441, Iran
| | - Farzaneh Omidi
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Moein Dehbashi
- Division of Genetics, Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan 8174673441, Iran
| | - Bahram Mohammad Soltani
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
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LEW SY, YOW YY, LIM LW, WONG KH. Antioxidant-mediated protective role of Hericium erinaceus (Bull.: Fr.) Pers. against oxidative damage in fibroblasts from Friedreich’s ataxia patient. FOOD SCIENCE AND TECHNOLOGY 2020. [DOI: 10.1590/fst.09919] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Subermaniam K, Yow YY, Lim SH, Koh OH, Wong KH. Malaysian macroalga Padina australis Hauck attenuates high dose corticosterone-mediated oxidative damage in PC12 cells mimicking the effects of depression. Saudi J Biol Sci 2020; 27:1435-1445. [PMID: 32489279 PMCID: PMC7254034 DOI: 10.1016/j.sjbs.2020.04.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/18/2020] [Accepted: 04/25/2020] [Indexed: 12/19/2022] Open
Abstract
Oxidative damage has been associated with the pathophysiology of depression. Macroalgae are equipped with antioxidant defense system to counteract the effects of free radicals. We explored the use of Malaysian Padina australis to attenuate high dose corticosterone-mediated oxidative damage in a cellular model mimicking depression. Fresh specimen of P. australis was freeze-dried and extracted sequentially with hexanes, ethyl acetate and ethanol. The extracts were screened for their phytochemical contents and antioxidant activities. Ethanol extract demonstrated the most potent antioxidant capacity and was selected for subsequent assays against high dose corticosterone of 600 µM-mediated oxidative damage in the rat pheochromocytoma (PC12) cells. The corticosterone reduced the cell viability, glutathione (GSH) level, aconitase activity, and mitochondrial membrane potential (MMP); and increased the lactate dehydrogenase (LDH) release, intracellular reactive oxygen species (ROS) level and apoptosis. However, the extent of oxidative damage was reversed by 0.25–0.5 mg/mL ethanol extract suggesting a possible role of P. australis-based antioxidants in the mitochondrial defense against constant ROS generation and regulation of antioxidant pathway. The effects were similar to that of desipramine, a tricyclic antidepressant. Our findings indicate that P. australis can be developed as a mitochondria-targeted antioxidant to mitigate antidepressant-like effects.
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Affiliation(s)
- Kogilavani Subermaniam
- Department of Anatomy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.,Examination and Certification Unit, Training Management Division, Ministry of Health Malaysia, 62675 Putrajaya, Wilayah Persekutuan Putrajaya, Malaysia
| | - Yoon Yen Yow
- Department of Biological Sciences, School of Science & Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Siew Huah Lim
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Ong Hui Koh
- Department of Psychological Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kah Hui Wong
- Department of Anatomy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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BK Ca ( Slo) Channel Regulates Mitochondrial Function and Lifespan in Drosophila melanogaster. Cells 2019; 8:cells8090945. [PMID: 31438578 PMCID: PMC6770356 DOI: 10.3390/cells8090945] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/13/2019] [Accepted: 08/20/2019] [Indexed: 12/20/2022] Open
Abstract
BKCa channels, originally discovered in Drosophila melanogaster as slowpoke (slo), are recognized for their roles in cellular and organ physiology. Pharmacological approaches implicated BKCa channels in cellular and organ protection possibly for their ability to modulate mitochondrial function. However, the direct role of BKCa channels in regulating mitochondrial structure and function is not deciphered. Here, we demonstrate that BKCa channels are present in fly mitochondria, and slo mutants show structural and functional defects in mitochondria. slo mutants display an increase in reactive oxygen species and the modulation of ROS affected their survival. We also found that the absence of BKCa channels reduced the lifespan of Drosophila, and overexpression of human BKCa channels in flies extends life span in males. Our study establishes the presence of BKCa channels in mitochondria of Drosophila and ascertains its novel physiological role in regulating mitochondrial structural and functional integrity, and lifespan.
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12
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Clay A, Hearle P, Schadt K, Lynch DR. New developments in pharmacotherapy for Friedreich ataxia. Expert Opin Pharmacother 2019; 20:1855-1867. [PMID: 31311349 DOI: 10.1080/14656566.2019.1639671] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Introduction: Friedreich ataxia (FRDA), a rare disease caused by the deficiency of the mitochondrial matrix protein frataxin, affects roughly 1 in 50,000 individuals worldwide. Current and emerging therapies focus on reversing the deleterious effects of such deficiency including mitochondrial augmentation and increasing frataxin levels, providing the possibility of treatment options for this physiologically complex, multisystem disorder. Areas covered: In this review article, the authors discuss the current and prior in vivo and in vitro research studies related to the treatment of FRDA, with a particular interest in future implications of each therapy. Expert opinion: Since the discovery of FXN in 1996, multiple clinical trials have occurred or are currently occurring; at a rapid pace for a rare disease. These trials have been directed at the augmentation of mitochondrial function and/or alleviation of symptoms and are not regarded as potential cures in FRDA. Either a combination of therapies or a drug that replaces or increases the pathologically low levels of frataxin better represent potential cures in FRDA.
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Affiliation(s)
- Alexandra Clay
- Division of Neurology, Children's Hospital of Philadelphia , Philadelphia , PA , USA
| | - Patrick Hearle
- Division of Neurology, Children's Hospital of Philadelphia , Philadelphia , PA , USA
| | - Kim Schadt
- Division of Neurology, Children's Hospital of Philadelphia , Philadelphia , PA , USA
| | - David R Lynch
- Division of Neurology, Children's Hospital of Philadelphia , Philadelphia , PA , USA
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Dzul SP, Rocha AG, Rawat S, Kandegedara A, Kusowski A, Pain J, Murari A, Pain D, Dancis A, Stemmler TL. In vitro characterization of a novel Isu homologue from Drosophila melanogaster for de novo FeS-cluster formation. Metallomics 2017; 9:48-60. [PMID: 27738674 DOI: 10.1039/c6mt00163g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
FeS-clusters are utilized by numerous proteins within several biological pathways that are essential for life. In eukaryotes, the primary FeS-cluster production pathway is the mitochondrial iron-sulfur cluster (ISC) pathway. In Saccharomyces cerevisiae, de novo FeS-cluster formation is accomplished through coordinated assembly with the substrates iron and sulfur by the scaffold assembly protein "Isu1". Sulfur for cluster assembly is provided by cysteine desulfurase "Nfs1", a protein that works in union with its accessory protein "Isd11". Frataxin "Yfh1" helps direct cluster assembly by serving as a modulator of Nfs1 activity, by assisting in the delivery of sulfur and Fe(ii) to Isu1, or more likely through a combination of these and other possible roles. In vitro studies on the yeast ISC machinery have been limited, however, due to the inherent instability of recombinant Isu1. Isu1 is a molecule prone to degradation and aggregation. To circumvent Isu1 instability, we have replaced yeast Isu1 with the fly ortholog to stabilize our in vitro ISC assembly system and assist us in elucidating molecular details of the yeast ISC pathway. Our laboratory previously observed that recombinant frataxin from Drosophila melanogaster has remarkable stability compared to the yeast ortholog. Here we provide the first characterization of D. melanogaster Isu1 (fIscU) and demonstrate its ability to function within the yeast ISC machinery both in vivo and in vitro. Recombinant fIscU has physical properties similar to that of yeast Isu1. It functions as a stable dimer with similar Fe(ii) affinity and ability to form two 2Fe-2S clusters as the yeast dimer. The fIscU and yeast ISC proteins are compatible in vitro; addition of Yfh1 to Nfs1-Isd11 increases the rate of FeS-cluster formation on fIscU to a similar extent observed with Isu1. Finally, fIscU expressed in mitochondria of a yeast strain lacking Isu1 (and its paralog Isu2) is able to completely reverse the deletion phenotypes. These results demonstrate fIscU can functionally replace yeast Isu1 and it can serve as a powerful tool for exploring molecular details within the yeast ISC pathway.
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Affiliation(s)
- Stephen P Dzul
- Departments of Pharmaceutical Science, and Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA
| | - Agostinho G Rocha
- Department of Medicine, Division of Hematology-Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Swati Rawat
- Departments of Pharmaceutical Science, and Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA
| | - Ashoka Kandegedara
- Departments of Pharmaceutical Science, and Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA
| | - April Kusowski
- Departments of Pharmaceutical Science, and Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA
| | - Jayashree Pain
- Department of Pharmacology, Physiology, and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA
| | - Anjaneyulu Murari
- Department of Pharmacology, Physiology, and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA
| | - Debkumar Pain
- Department of Pharmacology, Physiology, and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA
| | - Andrew Dancis
- Department of Medicine, Division of Hematology-Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Timothy L Stemmler
- Departments of Pharmaceutical Science, and Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA
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Zacchi LF, Dittmar JC, Mihalevic MJ, Shewan AM, Schulz BL, Brodsky JL, Bernstein KA. Early-onset torsion dystonia: a novel high-throughput yeast genetic screen for factors modifying protein levels of torsinAΔE. Dis Model Mech 2017; 10:1129-1140. [PMID: 28768697 PMCID: PMC5611967 DOI: 10.1242/dmm.029926] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 07/18/2017] [Indexed: 12/12/2022] Open
Abstract
Dystonia is the third most common movement disorder, but its diagnosis and treatment remain challenging. One of the most severe types of dystonia is early-onset torsion dystonia (EOTD). The best studied and validated EOTD-associated mutation, torsinAΔE, is a deletion of a C-terminal glutamate residue in the AAA+ ATPase torsinA. TorsinA appears to be an endoplasmic reticulum (ER)/nuclear envelope chaperone with multiple roles in the secretory pathway and in determining subcellular architecture. Many functions are disabled in the torsinAΔE variant, and torsinAΔE is also less stable than wild-type torsinA and is a substrate for ER-associated degradation. Nevertheless, the molecular factors involved in the biogenesis and degradation of torsinA and torsinAΔE have not been fully explored. To identify conserved cellular factors that can alter torsinAΔE protein levels, we designed a new high-throughput, automated, genome-wide screen utilizing our validated Saccharomyces cerevisiae torsinA expression system. By analyzing the yeast non-essential gene deletion collection, we identified 365 deletion strains with altered torsinAΔE steady-state levels. One notable hit was EUG1, which encodes a member of the protein disulfide isomerase family (PDIs). PDIs reside in the ER and catalyze the formation of disulfide bonds, mediate protein quality control and aid in nascent protein folding. We validated the role of select human PDIs in torsinA biogenesis in mammalian cells and found that overexpression of PDIs reduced the levels of torsinA and torsinAΔE. Together, our data report the first genome-wide screen to identify cellular factors that alter expression levels of the EOTD-associated protein torsinAΔE. More generally, the identified hits help in dissecting the cellular machinery involved in folding and degrading a torsinA variant, and constitute potential therapeutic factors for EOTD. This screen can also be readily adapted to identify factors impacting the levels of any protein of interest, considerably expanding the applicability of yeast in both basic and applied research.
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Affiliation(s)
- Lucía F Zacchi
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - John C Dittmar
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Michael J Mihalevic
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, 5117 Centre Avenue, UPCI Research Pavilion, 2.42e, Pittsburgh, PA 15213, USA
| | - Annette M Shewan
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jeffrey L Brodsky
- Department of Biological Sciences, A320 Langley Hall, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Kara A Bernstein
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, 5117 Centre Avenue, UPCI Research Pavilion, 2.42e, Pittsburgh, PA 15213, USA
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15
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Elsaid MF, Chalhoub N, Ben-Omran T, Kumar P, Kamel H, Ibrahim K, Mohamoud Y, Al-Dous E, Al-Azwani I, Malek JA, Suhre K, Ross ME, Aleem AA. Mutation in noncoding RNA RNU12 causes early onset cerebellar ataxia. Ann Neurol 2017; 81:68-78. [PMID: 27863452 DOI: 10.1002/ana.24826] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Exome sequences account for only 2% of the genome and may overlook mutations causing disease. To obtain a more complete view, whole genome sequencing (WGS) was analyzed in a large consanguineous family in which members displayed autosomal recessively inherited cerebellar ataxia manifesting before 2 years of age. METHODS WGS from blood-derived genomic DNA was used for homozygosity mapping and a rare variant search. RNA from isolated blood leukocytes was used for quantitative polymerase chain reaction (PCR), RNA sequencing, and comparison of the transcriptomes of affected and unaffected family members. RESULTS WGS revealed a point mutation in noncoding RNA RNU12 that was associated with early onset cerebellar ataxia. The U12-dependent minor spliceosome edits 879 known transcripts. Reverse transcriptase PCR demonstrated minor intron retention in all of 9 randomly selected RNAs from this group, and RNAseq showed splicing disruption specific to all U12-type introns detected in blood monocytes from affected individuals. Moreover, 144 minor intron-containing RNAs were differentially expressed, including transcripts for 3 genes previously associated with cerebellar neurodegeneration. INTERPRETATION Interference with particular spliceosome components, including small nuclear RNAs, cause reproducible uniquely distributed phenotypic and transcript-specific effects, making this an important category of disease-associated mutation. Our approach to differential expression analysis of minor intron-containing genes is applicable to other diseases involving altered transcriptome processing. ANN NEUROL 2017;81:68-78.
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Affiliation(s)
| | - Nader Chalhoub
- Neurogenetics, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Tawfeg Ben-Omran
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Pankaj Kumar
- Bioinformatics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hussein Kamel
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Khalid Ibrahim
- Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | | | - Eman Al-Dous
- Genomics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Iman Al-Azwani
- Genomics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Joel A Malek
- Genomics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Karsten Suhre
- Bioinformatics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - M Elizabeth Ross
- Neurogenetics, Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY
| | - Alice Abdel Aleem
- Neurogenetics, Weill Cornell Medicine-Qatar, Doha, Qatar.,Neurogenetics, Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY
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16
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Gramegna LL, Tonon C, Manners DN, Pini A, Rinaldi R, Zanigni S, Bianchini C, Evangelisti S, Fortuna F, Carelli V, Testa C, Lodi R. Combined Cerebellar Proton MR Spectroscopy and DWI Study of Patients with Friedreich’s Ataxia. THE CEREBELLUM 2016; 16:82-88. [DOI: 10.1007/s12311-016-0767-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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17
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Barupala DP, Dzul SP, Riggs-Gelasco PJ, Stemmler TL. Synthesis, delivery and regulation of eukaryotic heme and Fe-S cluster cofactors. Arch Biochem Biophys 2016; 592:60-75. [PMID: 26785297 PMCID: PMC4784227 DOI: 10.1016/j.abb.2016.01.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 11/25/2022]
Abstract
In humans, the bulk of iron in the body (over 75%) is directed towards heme- or Fe-S cluster cofactor synthesis, and the complex, highly regulated pathways in place to accomplish biosynthesis have evolved to safely assemble and load these cofactors into apoprotein partners. In eukaryotes, heme biosynthesis is both initiated and finalized within the mitochondria, while cellular Fe-S cluster assembly is controlled by correlated pathways both within the mitochondria and within the cytosol. Iron plays a vital role in a wide array of metabolic processes and defects in iron cofactor assembly leads to human diseases. This review describes progress towards our molecular-level understanding of cellular heme and Fe-S cluster biosynthesis, focusing on the regulation and mechanistic details that are essential for understanding human disorders related to the breakdown in these essential pathways.
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Affiliation(s)
- Dulmini P Barupala
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA
| | - Stephen P Dzul
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA
| | | | - Timothy L Stemmler
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA.
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18
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Cornelius C, Koverech G, Crupi R, Di Paola R, Koverech A, Lodato F, Scuto M, Salinaro AT, Cuzzocrea S, Calabrese EJ, Calabrese V. Osteoporosis and alzheimer pathology: Role of cellular stress response and hormetic redox signaling in aging and bone remodeling. Front Pharmacol 2014; 5:120. [PMID: 24959146 PMCID: PMC4050335 DOI: 10.3389/fphar.2014.00120] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/06/2014] [Indexed: 12/24/2022] Open
Abstract
Alzheimer’s disease (AD) and osteoporosis are multifactorial progressive degenerative disorders. Increasing evidence shows that osteoporosis and hip fracture are common complication observed in AD patients, although the mechanisms underlying this association remain poorly understood. Reactive oxygen species (ROS) are emerging as intracellular redox signaling molecules involved in the regulation of bone metabolism, including receptor activator of nuclear factor-κB ligand-dependent osteoclast differentiation, but they also have cytotoxic effects that include lipoperoxidation and oxidative damage to proteins and DNA. ROS generation, which is implicated in the regulation of cellular stress response mechanisms, is an integrated, highly regulated, process under control of redox sensitive genes coding for redox proteins called vitagenes. Vitagenes, encoding for proteins such as heat shock proteins (Hsps) Hsp32, Hsp70, the thioredoxin, and the sirtuin protein, represent a systems controlling a complex network of intracellular signaling pathways relevant to life span and involved in the preservation of cellular homeostasis under stress conditions. Consistently, nutritional anti-oxidants have demonstrated their neuroprotective potential through a hormetic-dependent activation of vitagenes. The biological relevance of dose–response affects those strategies pointing to the optimal dosing to patients in the treatment of numerous diseases. Thus, the heat shock response has become an important hormetic target for novel cytoprotective strategies focusing on the pharmacological development of compounds capable of modulating stress response mechanisms. Here we discuss possible signaling mechanisms involved in the activation of vitagenes which, relevant to bone remodeling and through enhancement of cellular stress resistance provide a rationale to limit the deleterious consequences associated to homeostasis disruption with consequent impact on the aging process.
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Affiliation(s)
- Carolin Cornelius
- Department of Chemistry, University of Catania Catania, Italy ; Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine Messina, Italy
| | - Guido Koverech
- Department of Biomedical Sciences, University of Catania Catania, Italy
| | - Rosalia Crupi
- Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine Messina, Italy
| | - Rosanna Di Paola
- Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine Messina, Italy
| | - Angela Koverech
- Department of Biomedical Sciences, University of Catania Catania, Italy
| | - Francesca Lodato
- Department of Biomedical Sciences, University of Catania Catania, Italy
| | - Maria Scuto
- Department of Biomedical Sciences, University of Catania Catania, Italy
| | - Angela T Salinaro
- Department of Biomedical Sciences, University of Catania Catania, Italy
| | - Salvatore Cuzzocrea
- Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine Messina, Italy ; University of Manchester Manchester, UK
| | - Edward J Calabrese
- Environmental Health Sciences Division, School of Public Health, University of Massachusetts Amherst, MA, USA
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19
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Carletti B, Piermarini E, Tozzi G, Travaglini L, Torraco A, Pastore A, Sparaco M, Petrillo S, Carrozzo R, Bertini E, Piemonte F. Frataxin silencing inactivates mitochondrial Complex I in NSC34 motoneuronal cells and alters glutathione homeostasis. Int J Mol Sci 2014; 15:5789-806. [PMID: 24714088 PMCID: PMC4013596 DOI: 10.3390/ijms15045789] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 03/24/2014] [Accepted: 03/31/2014] [Indexed: 02/06/2023] Open
Abstract
Friedreich's ataxia (FRDA) is a hereditary neurodegenerative disease characterized by a reduced synthesis of the mitochondrial iron chaperon protein frataxin as a result of a large GAA triplet-repeat expansion within the first intron of the frataxin gene. Despite neurodegeneration being the prominent feature of this pathology involving both the central and the peripheral nervous system, information on the impact of frataxin deficiency in neurons is scant. Here, we describe a neuronal model displaying some major biochemical and morphological features of FRDA. By silencing the mouse NSC34 motor neurons for the frataxin gene with shRNA lentiviral vectors, we generated two cell lines with 40% and 70% residual amounts of frataxin, respectively. Frataxin-deficient cells showed a specific inhibition of mitochondrial Complex I (CI) activity already at 70% residual frataxin levels, whereas the glutathione imbalance progressively increased after silencing. These biochemical defects were associated with the inhibition of cell proliferation and morphological changes at the axonal compartment, both depending on the frataxin amount. Interestingly, at 70% residual frataxin levels, the in vivo treatment with the reduced glutathione revealed a partial rescue of cell proliferation. Thus, NSC34 frataxin silenced cells could be a suitable model to study the effect of frataxin deficiency in neurons and highlight glutathione as a potential beneficial therapeutic target for FRDA.
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Affiliation(s)
- Barbara Carletti
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Emanuela Piermarini
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Giulia Tozzi
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Lorena Travaglini
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Alessandra Torraco
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Anna Pastore
- Biochemistry Laboratory, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Marco Sparaco
- Division of Neurology, Department of Neurosciences, Azienda Ospedaliera, "G. Rummo", Via Pacevecchia 53, 82100 Benevento, Italy.
| | - Sara Petrillo
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Rosalba Carrozzo
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Enrico Bertini
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Fiorella Piemonte
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Piazza S. Onofrio 4, 00165 Rome, Italy.
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20
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Santos ELW, Dias BHM, Andrade ACRD, Pascoal AMH, Vasconcelos Filho FED, Medeiros FDC, Guimarães SB. Effects of acupuncture and electroacupuncture on estradiol-induced inflammation and oxidative stress in health rodents. Acta Cir Bras 2013; 28:582-8. [DOI: 10.1590/s0102-86502013000800005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 07/16/2013] [Indexed: 11/22/2022] Open
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Richardson TE, Kelly HN, Yu AE, Simpkins JW. Therapeutic strategies in Friedreich's ataxia. Brain Res 2013; 1514:91-7. [PMID: 23587934 PMCID: PMC4461031 DOI: 10.1016/j.brainres.2013.04.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 04/02/2013] [Accepted: 04/02/2013] [Indexed: 10/26/2022]
Abstract
First established as a diagnosis by Nikolaus Friedreich in 1863, Friedreich's ataxia (FA) is an autosomal recessive progressive neurodegenerative disorder cause by a trinucleotide repeat expansion. FA begins with the functional absence of the FXN gene product frataxin, a protein whose exact function still remains unknown. This absence results in impaired intracellular antioxidant defenses, dysregulation of iron-sulfur cluster proteins, depression of aerobic electron transport chain respiration, massive mitochondrial dysfunction, and ultimately cell death in the brain, spinal cord and heart. Herein, we review the molecular and cellular pathogenesis leading to widespread organ system dysfunction, as well as current therapeutic research aimed at preventing the debilitating effects of frataxin loss and preventing the signs and symptoms associated of FA. We also discuss the ongoing treatment strategies employed by our laboratory to prevent mitochondrial damage using synergistic effects of 17β-estradiol and methylene blue, previously shown by our group and others to have protective effects in human FA fibroblasts. This article is part of a Special Issue entitled Hormone Therapy.
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Affiliation(s)
- Timothy E. Richardson
- Institute for Aging and Alzheimer’s Disease Research, Department of Pharmacology & Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
- Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Heather N. Kelly
- Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Amanda E. Yu
- Institute for Aging and Alzheimer’s Disease Research, Department of Pharmacology & Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
- Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - James W. Simpkins
- Institute for Aging and Alzheimer’s Disease Research, Department of Pharmacology & Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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22
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Cornelius C, Perrotta R, Graziano A, Calabrese EJ, Calabrese V. Stress responses, vitagenes and hormesis as critical determinants in aging and longevity: Mitochondria as a "chi". Immun Ageing 2013; 10:15. [PMID: 23618527 PMCID: PMC3644272 DOI: 10.1186/1742-4933-10-15] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 04/13/2013] [Indexed: 01/01/2023]
Abstract
Understanding mechanisms of aging and determinants of life span will help to reduce age-related morbidity and facilitate healthy aging. Average lifespan has increased over the last centuries, as a consequence of medical and environmental factors, but maximal life span remains unchanged. Extension of maximal life span is currently possible in animal models with measures such as genetic manipulations and caloric restriction (CR). CR appears to prolong life by reducing reactive oxygen species (ROS)-mediated oxidative damage. But ROS formation, which is positively implicated in cellular stress response mechanisms, is a highly regulated process controlled by a complex network of intracellular signaling pathways. By sensing the intracellular nutrient and energy status, the functional state of mitochondria, and the concentration of ROS produced in mitochondria, the longevity network regulates life span across species by coordinating information flow along its convergent, divergent and multiply branched signaling pathways, including vitagenes which are genes involved in preserving cellular homeostasis during stressful conditions. Vitagenes encode for heat shock proteins (Hsp) Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. Dietary antioxidants, have recently been demonstrated to be neuroprotective through the activation of hormetic pathways, including vitagenes. The hormetic dose-response, challenges long-standing beliefs about the nature of the dose-response in a lowdose zone, having the potential to affect significantly the design of pre-clinical studies and clinical trials as well as strategies for optimal patient dosing in the treatment of numerous diseases. Given the broad cytoprotective properties of the heat shock response there is now strong interest in discovering and developing pharmacological agents capable of inducing stress responses. Here we focus on possible signaling mechanisms involved in the activation of vitagenes resulting in enhanced defense against energy and stress resistance homeostasis dysiruption with consequent impact on longevity processes.
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Affiliation(s)
- Carolin Cornelius
- Department of Chemistry University of Catania, Viale Andrea Doria, 95100 Catania, Italy
| | - Rosario Perrotta
- Department of Medicine and Surgery, University of Catania, Viale Andrea Doria, Catania, 95100, Italy
| | - Antonio Graziano
- Department of Medicine and Surgery, University of Catania, Viale Andrea Doria, Catania, 95100, Italy
| | - Edward J Calabrese
- Environmental Health Sciences Division, School of Public Health, University of Massachusetts, Amherst, MA, USA
| | - Vittorio Calabrese
- Department of Chemistry University of Catania, Viale Andrea Doria, 95100 Catania, Italy
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23
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Giunti P, Greenfield J, Stevenson AJ, Parkinson MH, Hartmann JL, Sandtmann R, Piercy J, O'Hara J, Casas LR, Smith FM. Impact of Friedreich's Ataxia on health-care resource utilization in the United Kingdom and Germany. Orphanet J Rare Dis 2013; 8:38. [PMID: 23448170 PMCID: PMC3599305 DOI: 10.1186/1750-1172-8-38] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 01/16/2013] [Indexed: 11/12/2022] Open
Abstract
Background Friedreich’s Ataxia (FRDA) is a neurodegenerative disorder that causes progressive damage to the central and peripheral nervous systems having a significant impact upon quality of life. With little information in the literature, cross-sectional observational studies were conducted in the UK and Germany to collect data on resource use and the burden of the disease on individuals and their caregivers. Methods Cross-sectional observational studies were conducted in the UK and Germany to estimate the burden of FRDA on individuals and on the respective healthcare systems. A total of 75 individuals in the UK and 28 in Germany were recruited to the study. Participants in both countries were asked to complete a Patient and Caregiver Information Form (PCIF), regarding access to, and use of, healthcare resources, and the impact FRDA has on their lifestyle. In Germany, doctors were asked to complete a Patient Record Form (PRF). Analyses of annual direct and indirect resource utilization were conducted for both countries while costs were calculated for the UK only. These figures were compared to the costs associated with Parkinson’s disease; one of the most common neurodegenerative conditions and the one most similar in terms of disease progression. Results The results showed that the annual burden of FRDA is significant and falls on the health and social care sectors, on society, on caregivers and on the individuals themselves. In the UK FRDA had a total annual cost per person of between £11,818 and £18,774 depending on whether the cost of long-term unemployment was included. Typically the largest component of direct costs is associated with professional care. Given the high proportion of children and young adults recruited and the long disease duration, (typically 40-50 years for FRDA, compared with 20 years for Parkinson’s disease), these figures may underestimate the true burden of the disease. Conclusion It is hoped that these estimates of resource utilization, can help in understanding the previously unquantified burden of FRDA. Given the long disease duration, management strategies should seek to minimise the impact of the condition on individuals and their caregivers, while maximising quality of life.
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Affiliation(s)
- Paola Giunti
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK.
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Skeletal Muscle Involvement in Friedreich Ataxia and Potential Effects of Recombinant Human Erythropoietin Administration on Muscle Regeneration and Neovascularization. J Neuropathol Exp Neurol 2012; 71:708-15. [DOI: 10.1097/nen.0b013e31825fed76] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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25
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Akhlaghi H, Corben L, Georgiou-Karistianis N, Bradshaw J, Delatycki MB, Storey E, Egan GF. A functional MRI study of motor dysfunction in Friedreich's ataxia. Brain Res 2012; 1471:138-54. [PMID: 22771856 DOI: 10.1016/j.brainres.2012.06.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 06/25/2012] [Accepted: 06/26/2012] [Indexed: 10/28/2022]
Abstract
Friedreich's ataxia (FRDA) is the most common form of hereditary ataxia. In addition to proximal spinal cord and brain stem atrophy, mild to moderate atrophy of the cerebellum has been reported in advanced FRDA. The aim of this study was to examine dysfunction in motor-related areas involved in the execution of finger tapping tasks in individuals with FRDA, and to investigate functional re-organization of cortico-cerebellar, cortico-striatal and parieto-frontal loops as a result of the cerebellar pathology. Thirteen right-handed individuals with FRDA and fourteen right-handed controls participated. Functional MRI images were acquired during four different finger tapping tasks consisting of visually cued regular and irregular single finger tapping tasks, a self-paced regular finger tapping task, and a visually cued multi-finger tapping task. Both groups showed significant activation of the motor-related network including the pre-central cortex and supplementary motor area bilaterally; the left primary motor cortex, somatosensory cortex and putamen; and the right cerebellum. During the visually cued regular finger tapping task, the right hemisphere of the cerebellar cortex, bilateral supplementary motor areas and right inferior parietal cortex showed higher activation in the healthy control group, while in individuals with FRDA the left premotor cortex, left somatosensory cortex and left inferior parietal cortex were more active. In addition, during the visually cued irregular finger tapping task, the right middle temporal gyrus in the control group and the right superior parietal lobule and left superior and middle temporal gyri in the individuals with FRDA showed higher activation. During visually cued multi-finger tapping task, the control group showed higher activation in the bilateral middle frontal gyri, bilateral somatosensory cortices, bilateral inferior parietal lobules, left premotor cortex, left supplementary area, right superior frontal gyrus and right cerebellum, while individuals with FRDA showed increased activity in the left inferior parietal lobule, left primary motor cortex, left middle occipital gyrus, right somatosensory cortex and the left cerebellum. Only the right crus I/II of the cerebellum showed higher activation in individuals with FRDA during the self-paced regular finger tapping task, whereas wide-spread regions including the left superior frontal gyrus, left central opercular cortex, left somatosensory cortex, left putamen, right cerebellum, bilateral primary motor cortices, bilateral inferior parietal lobules and the left insula were more active in the control group. Although the pattern of the BOLD signal from the putamen was different during the self-paced regular finger tapping task to the other tasks in controls, in individuals with FRDA there was no distinction of the signal between the tasks suggesting that primary cerebellar pathology may cause secondary basal ganglia dysregulation. While individuals with FRDA tapped at a slightly lower rate (0.59Hz) compared with controls (0.74Hz) they showed significantly decreased activity of the SMA and the inferior parietal lobule, which may suggest disruption to the fronto-parietal connections. These findings suggest that the motor impairments in individuals with FRDA result from dysfunction extending beyond the spinal cord and cerebellum to include sub-cortical and cortical brain regions.
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Affiliation(s)
- H Akhlaghi
- Florey Neurosciences Institutes, University of Melbourne, Parkville, Australia; Centre for Neuroscience, University of Melbourne, Parkville, Australia
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Li H, Outten CE. Monothiol CGFS glutaredoxins and BolA-like proteins: [2Fe-2S] binding partners in iron homeostasis. Biochemistry 2012; 51:4377-89. [PMID: 22583368 DOI: 10.1021/bi300393z] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Monothiol glutaredoxins (Grxs) with a signature CGFS active site and BolA-like proteins have recently emerged as novel players in iron homeostasis. Elegant genetic and biochemical studies examining the functional and physical interactions of CGFS Grxs in the fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe have unveiled their essential roles in intracellular iron signaling, iron trafficking, and the maturation of Fe-S cluster proteins. Biophysical and biochemical analyses of the [2Fe-2S] bridging interaction between CGFS Grxs and a BolA-like protein in S. cerevisiae provided the first molecular-level understanding of the iron regulation mechanism in this model eukaryote and established the ubiquitous CGFS Grxs and BolA-like proteins as novel Fe-S cluster-binding regulatory partners. Parallel studies focused on Escherichia coli and human homologues for CGFS Grxs and BolA-like proteins have supported the studies in yeast and provided additional clues about their involvement in cellular iron metabolism. Herein, we review recent progress in uncovering the cellular and molecular mechanisms by which CGFS Grxs and BolA-like proteins help regulate iron metabolism in both eukaryotic and prokaryotic organisms.
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Affiliation(s)
- Haoran Li
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
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Estrogen prevents oxidative damage to the mitochondria in Friedreich's ataxia skin fibroblasts. PLoS One 2012; 7:e34600. [PMID: 22509330 PMCID: PMC3318005 DOI: 10.1371/journal.pone.0034600] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 03/06/2012] [Indexed: 11/20/2022] Open
Abstract
Estrogen and estrogen-related compounds have been shown to have very potent cytoprotective properties in a wide range of disease models, including an in vitro model of Friedreich's ataxia (FRDA). This study describes a potential estrogen receptor (ER)-independent mechanism by which estrogens act to protect human FRDA skin fibroblasts from a BSO-induced oxidative insult resulting from inhibition of de novo glutathione (GSH) synthesis. We demonstrate that phenolic estrogens, independent of any known ER, are able to prevent lipid peroxidation and mitochondrial membrane potential (ΔΨm) collapse, maintain ATP at near control levels, increase oxidative phosphorylation and maintain activity of aconitase. Estrogens did not, however, prevent BSO from depleting GSH or induce an increased expression level of GSH. The cytoprotective effects of estrogen appear to be due to a direct overall reduction in oxidative damage to the mitochondria, enabling the FRDA fibroblast mitochondria to generate sufficient ATP for energy requirements and better survive oxidative stress. These data support the hypothesis that phenol ring containing estrogens are possible candidate drugs for the delay and/or prevention of FRDA symptoms.
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Abstract
Estrogens have been shown to have protective effects on a wide range of cell types and animal models for many neurodegenerative diseases. The present study demonstrates the cytoprotective effects of 17β-estradiol (E2) and estrogen-like compounds in an in vitro model of Friedreich's ataxia (FRDA) using human donor FRDA skin fibroblasts. FRDA fibroblasts are extremely sensitive to free radical damage and oxidative stress, produced here using l-buthionine (S,R)-sulfoximine to inhibit de novo glutathione synthesis. We have shown that the protective effect of E2 in the face of l-buthionine (S,R)-sulfoximine -induced oxidative stress is independent of estrogen receptor-α, estrogen receptor-β or G protein-coupled receptor 30 as shown by the inability of either ICI 182,780 or G15 to inhibit the E2-mediated protection. These cytoprotective effects appear to be dependent on antioxidant properties and the phenolic structure of estradiol as demonstrated by the observation that all phenolic compounds tested were protective, whereas all nonphenolic compounds were inactive, and the observation that the phenolic compounds reduced the levels of reactive oxygen species, whereas the nonphenolic compounds did not. These data show for the first time that phenolic E2-like compounds are potent protectors against oxidative stress-induced cell death in FRDA fibroblasts and are possible candidate drugs for the treatment and prevention of FRDA symptoms.
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Affiliation(s)
- Timothy E Richardson
- Institute for Aging and Alzheimer’s Disease Research, Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA.
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Lee YC, Liao YC, Wang PS, Lee IH, Lin KP, Soong BW. Comparison of cerebellar ataxias: A three-year prospective longitudinal assessment. Mov Disord 2011; 26:2081-7. [DOI: 10.1002/mds.23809] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 04/23/2011] [Accepted: 04/28/2011] [Indexed: 11/10/2022] Open
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The test of everyday attention reveals significant sustained volitional attention and working memory deficits in friedreich ataxia. J Int Neuropsychol Soc 2011; 17:196-200. [PMID: 21083965 DOI: 10.1017/s1355617710001347] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Sustained volitional attention and working memory capacity was examined for the first time in people with Friedreich ataxia (FRDA). We administered subtests of the Test of Everyday Attention to 16 individuals with molecularly confirmed FRDA and gender-, age-, and IQ-matched controls. Clinically significant impairment in working memory and sustained volitional attention was evident. Working memory deficits correlated significantly with GAA repeat number on the shorter allele of the FXN gene, and separately, with disease severity, as measured by the Friedreich Ataxia Rating Scale score. Sustained volitional attention was not correlated with disease parameters, suggesting that this impairment may not be related to the disease process in a simple way. The deficits observed may be the result of disruption to corticocerebellar pathways, or directly related to the cortical and/or cerebellar pathology evident in people with FRDA.
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Cellular Stress Responses, Mitostress and Carnitine Insufficiencies as Critical Determinants in Aging and Neurodegenerative Disorders: Role of Hormesis and Vitagenes. Neurochem Res 2010; 35:1880-915. [DOI: 10.1007/s11064-010-0307-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2010] [Indexed: 02/07/2023]
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Deutsch EC, Santani AB, Perlman SL, Farmer JM, Stolle CA, Marusich MF, Lynch DR. A rapid, noninvasive immunoassay for frataxin: utility in assessment of Friedreich ataxia. Mol Genet Metab 2010; 101:238-45. [PMID: 20675166 PMCID: PMC2996613 DOI: 10.1016/j.ymgme.2010.07.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 07/01/2010] [Accepted: 07/01/2010] [Indexed: 11/20/2022]
Abstract
Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by reduced amounts of the mitochondrial protein frataxin. Frataxin levels in research studies are typically measured via Western blot analysis from patient fibroblasts, lymphocytes, or muscle biopsies; none of these is ideal for rapid detection in large scale clinical studies. Recently, a rapid, noninvasive lateral flow immunoassay was developed to accurately measure picogram levels of frataxin protein and shown to distinguish lymphoblastoid cells from FRDA carriers, patients and controls. We expanded the immunoassay to measure frataxin directly in buccal cells and whole blood from a large cohort of controls, known carriers and patients typical of a clinical trial population. The assay in buccal cells shared a similar degree of variability with previous studies conducted in lymphoblastoid cells (~10% coefficient of variation in controls). Significant differences in frataxin protein quantity were seen between the mean group values of controls, carriers, and patient buccal cells (100, 50.2, and 20.9% of control, respectively) and in protein extracted from whole blood (100, 75.3, and 32.2%, respectively), although there was some overlap between the groups. In addition, frataxin levels were inversely related to GAA repeat length and correlated directly with age of onset. Subjects with one expanded GAA repeat and an identified frataxin point mutation also carried frataxin levels in the disease range. Some patients displaying an FRDA phenotype but carrying only a single identifiable mutation had frataxin levels in the FRDA patient range. One patient from this group has a novel deletion that included exons 2 and 3 of the FXN gene based on multiplex ligation-dependent probe amplification (MLPA) analysis of the FXN gene. The lateral flow immunoassay may be a useful means to noninvasively assess frataxin levels repetitively with minimal discomfort in FRDA patients in specific situations such as clinical trials, and as a complementary diagnostic tool to aid in identification and characterization of atypical patients.
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Affiliation(s)
- Eric C. Deutsch
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
| | - Avni B. Santani
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Susan L. Perlman
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095
| | - Jennifer M. Farmer
- Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Catherine A. Stolle
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | | | - David R. Lynch
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
- Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
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Mouse models of neurological disorders—A comparison of heritable and acquired traits. Biochim Biophys Acta Mol Basis Dis 2010; 1802:785-95. [DOI: 10.1016/j.bbadis.2010.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 05/17/2010] [Accepted: 05/19/2010] [Indexed: 01/17/2023]
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Iltis I, Hutter D, Bushara KO, Clark HB, Gross M, Eberly LE, Gomez CM, Oz G. (1)H MR spectroscopy in Friedreich's ataxia and ataxia with oculomotor apraxia type 2. Brain Res 2010; 1358:200-10. [PMID: 20713024 DOI: 10.1016/j.brainres.2010.08.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2010] [Revised: 08/07/2010] [Accepted: 08/09/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND AND AIM Friedreich's ataxia (FRDA) and ataxia with oculomotor apraxia type 2 (AOA2) are the two most frequent forms of autosomal recessive cerebellar ataxias. However, brain metabolism in these disorders is poorly characterized and biomarkers of the disease progression are lacking. We aimed at assessing the neurochemical profile of the pons, the cerebellar hemisphere and the vermis in patients with FRDA and AOA2 to identify potential biomarkers of these diseases. METHODS Short-echo, single-voxel proton ((1)H) magnetic resonance spectroscopy data were acquired from 8 volunteers with FRDA, 9 volunteers with AOA2, and 38 control volunteers at 4T. Disease severity was assessed by the Friedreich's Ataxia Rating Scale (FARS). RESULTS Neuronal loss/dysfunction was indicated in the cerebellar vermis and hemispheres in both diseases by lower total N-acetylaspartate levels than controls. The putative gliosis marker myo-inositol was higher than controls in the vermis and pons in AOA2 and in the vermis in FRDA. Total creatine, another potential gliosis marker, was higher in the cerebellar hemispheres in FRDA relative to controls. Higher glutamine in FRDA and lower glutamate in AOA2 than controls were observed in the vermis, indicating different mechanisms possibly leading to altered glutamatergic neurotransmission. In AOA2, total N-acetylaspartate levels in the cerebellum strongly correlated with the FARS score (p<0.01). CONCLUSION Distinct neurochemical patterns were observed in the two patient populations, warranting further studies with larger patient populations to determine if the alterations in metabolite levels observed here may be utilized to monitor disease progression and treatment.
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Affiliation(s)
- Isabelle Iltis
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN 55455, USA.
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Armstrong JS, Khdour O, Hecht SM. Does oxidative stress contribute to the pathology of Friedreich's ataxia? A radical question. FASEB J 2010; 24:2152-63. [PMID: 20219987 DOI: 10.1096/fj.09-143222] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Friedreich's ataxia (FRDA) is a hereditary neurodegenerative disease that frequently culminates in cardiac failure at an early age. FRDA is believed to arise from reduced synthesis of the mitochondrial iron chaperone frataxin due to impaired gene transcription, which leads to mitochondrial iron accumulation, dysfunction of mitochondrial Fe-S containing enzymes, and increased Fenton-mediated free radical production. Recent reports have challenged this generally accepted hypothesis, by suggesting that the oxidative stress component in FRDA is minimal and thereby questioning the benefit of antioxidant therapeutic strategies. We suggest that this apparent paradox results from the radically divergent chemistries of the participating reactive oxygen species (ROS), the major cellular subcompartments involved and the overall cellular responses to ROS. In this review, we consider these factors and conclude that oxidative stress does constitute a major contributing factor to FRDA pathology. This reaffirms the idea that the rational design of specific small molecule multifunctional antioxidants will benefit FRDA patients.
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Affiliation(s)
- Jeffrey S Armstrong
- Center for BioEnergetics, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.
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Marmolino D, Manto M, Acquaviva F, Vergara P, Ravella A, Monticelli A, Pandolfo M. PGC-1alpha down-regulation affects the antioxidant response in Friedreich's ataxia. PLoS One 2010; 5:e10025. [PMID: 20383327 PMCID: PMC2850922 DOI: 10.1371/journal.pone.0010025] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Accepted: 03/16/2010] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Cells from individuals with Friedreich's ataxia (FRDA) show reduced activities of antioxidant enzymes and cannot up-regulate their expression when exposed to oxidative stress. This blunted antioxidant response may play a central role in the pathogenesis. We previously reported that Peroxisome Proliferator Activated Receptor Gamma (PPARgamma) Coactivator 1-alpha (PGC-1alpha), a transcriptional master regulator of mitochondrial biogenesis and antioxidant responses, is down-regulated in most cell types from FRDA patients and animal models. METHODOLOGY/PRINCIPAL FINDINGS We used primary fibroblasts from FRDA patients and the knock in-knock out animal model for the disease (KIKO mouse) to determine basal superoxide dismutase 2 (SOD2) levels and the response to oxidative stress induced by the addition of hydrogen peroxide. We measured the same parameters after pharmacological stimulation of PGC-1alpha. Compared to control cells, PGC-1alpha and SOD2 levels were decreased in FRDA cells and did not change after addition of hydrogen peroxide. PGC-1alpha direct silencing with siRNA in control fibroblasts led to a similar loss of SOD2 response to oxidative stress as observed in FRDA fibroblasts. PGC-1alpha activation with the PPARgamma agonist (Pioglitazone) or with a cAMP-dependent protein kinase (AMPK) agonist (AICAR) restored normal SOD2 induction. Treatment of the KIKO mice with Pioglitazone significantly up-regulates SOD2 in cerebellum and spinal cord. CONCLUSIONS/SIGNIFICANCE PGC-1alpha down-regulation is likely to contribute to the blunted antioxidant response observed in cells from FRDA patients. This response can be restored by AMPK and PPARgamma agonists, suggesting a potential therapeutic approach for FRDA.
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Affiliation(s)
- Daniele Marmolino
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Mario Manto
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Fonds National de la Recherche Scientifique (FNRS), Brussels, Belgium
| | - Fabio Acquaviva
- Department of Cellular and Molecular Biology, University of Naples “Federico II”, Naples, Italy
| | - Paola Vergara
- Department of Cellular and Molecular Biology, University of Naples “Federico II”, Naples, Italy
| | - Ajay Ravella
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | | | - Massimo Pandolfo
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
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Abstract
Treatment of mitochondrial disorders (MIDs) is a challenge since there is only symptomatic therapy available and since only few randomized and controlled studies have been carried out, which demonstrate an effect of some of the symptomatic or supportive measures available. Symptomatic treatment of MIDs is based on mainstay drugs, blood transfusions, hemodialysis, invasive measures, surgery, dietary measures, and physiotherapy. Drug treatment may be classified as specific (treatment of epilepsy, headache, dementia, dystonia, extrapyramidal symptoms, Parkinson syndrome, stroke-like episodes, or non-neurological manifestations), non-specific (antioxidants, electron donors/acceptors, alternative energy sources, cofactors), or restrictive (avoidance of drugs known to be toxic for mitochondrial functions). Drugs which more frequently than in the general population cause side effects in MID patients include steroids, propofol, statins, fibrates, neuroleptics, and anti-retroviral agents. Invasive measures include implantation of a pacemaker, biventricular pacemaker, or implantable cardioverter defibrillator, or stent therapy. Dietary measures can be offered for diabetes, hyperlipidemia, or epilepsy (ketogenic diet, anaplerotic diet). Treatment should be individualized because of the peculiarities of mitochondrial genetics. Despite limited possibilities, symptomatic treatment should be offered to MID patients, since it can have a significant impact on the course and outcome.
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Wenz T. PGC-1α activation as a therapeutic approach in mitochondrial disease. IUBMB Life 2009; 61:1051-62. [DOI: 10.1002/iub.261] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Anderson GJ, Vulpe CD. Mammalian iron transport. Cell Mol Life Sci 2009; 66:3241-61. [PMID: 19484405 PMCID: PMC11115736 DOI: 10.1007/s00018-009-0051-1] [Citation(s) in RCA: 221] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Revised: 04/21/2009] [Accepted: 05/12/2009] [Indexed: 02/07/2023]
Abstract
Iron is essential for basic cellular processes but is toxic when present in excess. Consequently, iron transport into and out of cells is tightly regulated. Most iron is delivered to cells bound to plasma transferrin via a process that involves transferrin receptor 1, divalent metal-ion transporter 1 and several other proteins. Non-transferrin-bound iron can also be taken up efficiently by cells, although the mechanism is poorly understood. Cells can divest themselves of iron via the iron export protein ferroportin in conjunction with an iron oxidase. The linking of an oxidoreductase to a membrane permease is a common theme in membrane iron transport. At the systemic level, iron transport is regulated by the liver-derived peptide hepcidin which acts on ferroportin to control iron release to the plasma.
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Affiliation(s)
- Gregory Jon Anderson
- Iron Metabolism Laboratory, Queensland Institute of Medical Research, PO Royal Brisbane Hospital, QLD, Australia.
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Heterogeneity of nervous system mitochondria: Location, location, location! Exp Neurol 2009; 218:293-307. [DOI: 10.1016/j.expneurol.2009.05.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2009] [Revised: 04/30/2009] [Accepted: 05/08/2009] [Indexed: 01/03/2023]
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Abstract
Reactive oxygen and reactive nitrogen species (ROS/RNS) have been implicated in the pathogenesis of acute and chronic pancreatitis. Clinical and basic science studies have indicated that ROS/RNS formation processes are intimately linked to the development of the inflammatory disorders. The detrimental effects of highly reactive ROS/RNS are mediated by their direct actions on biomolecules (lipids, proteins, and nucleic acids) and activation of proinflammatory signal cascades, which subsequently lead to activation of immune responses. The present article summarizes the possible sources of ROS/RNS formation and the detailed signaling cascades implicated in the pathogenesis of pancreatic inflammation, as observed in acute and chronic pancreatitis. A therapeutic ROS/RNS-scavenging strategy has been advocated for decades; however, clinical studies examining such approaches have been inconsistent in their results. Emerging evidence indicates that pancreatitis-inducing ROS/RNS generation may be attenuated by targeting ROS/RNS-generating enzymes and upstream mediators.
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Affiliation(s)
- Po Sing Leung
- Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
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Spindler M, Beal MF, Henchcliffe C. Coenzyme Q10 effects in neurodegenerative disease. Neuropsychiatr Dis Treat 2009; 5:597-610. [PMID: 19966907 PMCID: PMC2785862 DOI: 10.2147/ndt.s5212] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Indexed: 12/13/2022] Open
Abstract
Coenzyme Q10 (CoQ10) is an essential cofactor in the mitochondrial respiratory chain, and as a dietary supplement it has recently gained attention for its potential role in the treatment of neurodegenerative disease. Evidence for mitochondrial dysfunction in neurodegenerative disorders derives from animal models, studies of mitochondria from patients, identification of genetic defects in patients with neurodegenerative disease, and measurements of markers of oxidative stress. Studies of in vitro models of neuronal toxicity and animal models of neurodegenerative disorders have demonstrated potential neuroprotective effects of CoQ10. With this data in mind, several clinical trials of CoQ10 have been performed in Parkinson's disease and atypical Parkinson's syndromes, Huntington's disease, Alzheimer disease, Friedreich's ataxia, and amyotrophic lateral sclerosis, with equivocal findings. CoQ10 is widely available in multiple formulations and is very well tolerated with minimal adverse effects, making it an attractive potential therapy. Phase III trials of high-dose CoQ10 in large sample sizes are needed to further ascertain the effects of CoQ10 in neurodegenerative diseases.
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Affiliation(s)
- Meredith Spindler
- Department of Neurology, Weill Medical, College of Cornell University, 525 east 68th Street, Suite F610, New York, NY, USA.
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Ba LA, Doering M, Burkholz T, Jacob C. Metal trafficking: from maintaining the metal homeostasis to future drug design. Metallomics 2009; 1:292-311. [DOI: 10.1039/b904533c] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Abstract
This article provides an overview of recent advances in the field of inherited ataxias. In the past few years, new causative mutations that broaden the diagnostic spectrum of ataxias have been described. In addition, important advances have unveiled the molecular pathology of these disorders, resulting in a classification based on the pathogenetic pathways rather than clinical or genetic features. As concepts of treatment principles emerge, debate continues as to whether such concepts might be applicable to more than one genetically defined disorder or whether each ataxia disorder requires its own unique therapeutic approach. New clinical assessment instruments have been developed that will facilitate future interventional trials. A recent phase 2 clinical trial suggested a positive effect of high-dose idebenone in Friedreich's ataxia, raising hopes that a treatment option will soon be available for this disorder.
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Sutak R, Xu X, Whitnall M, Kashem MA, Vyoral D, Richardson DR. Proteomic analysis of hearts from frataxin knockout mice: marked rearrangement of energy metabolism, a response to cellular stress and altered expression of proteins involved in cell structure, motility and metabolism. Proteomics 2008; 8:1731-41. [PMID: 18340635 DOI: 10.1002/pmic.200701049] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Indexed: 12/16/2023]
Abstract
A frequent cause of death in Friedreich's ataxia patients is cardiomyopathy, but the molecular alterations underlying this condition are unknown. We performed 2-DE to characterize the changes in protein expression of hearts using the muscle creatine kinase frataxin conditional knockout (KO) mouse. Pronounced changes in protein expression profile were observed in 9 week-old KO mice with severe cardiomyopathy. In contrast, only several proteins showed altered expression in asymptomatic 4 week-old KO mice. In hearts from frataxin KO mice, components of the iron-dependent complex-I and -II of the mitochondrial electron transport chain and enzymes involved in ATP homeostasis (creatine kinase, adenylate kinase) displayed decreased expression. Interestingly, the KO hearts exhibited increased expression of enzymes involved in the citric acid cycle, catabolism of branched-chain amino acids, ketone body utilization and pyruvate decarboxylation. This constitutes evidence of metabolic compensation due to decreased expression of electron transport proteins. There was also pronounced up-regulation of proteins involved in stress protection, such as a variety of chaperones, as well as altered expression of proteins involved in cellular structure, motility and general metabolism. This is the first report of the molecular changes at the protein level which could be involved in the cardiomyopathy of the frataxin KO mouse.
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Affiliation(s)
- Robert Sutak
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, Australia
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Go YM, Jones DP. Redox compartmentalization in eukaryotic cells. Biochim Biophys Acta Gen Subj 2008; 1780:1273-90. [PMID: 18267127 DOI: 10.1016/j.bbagen.2008.01.011] [Citation(s) in RCA: 464] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 01/11/2008] [Accepted: 01/14/2008] [Indexed: 12/21/2022]
Abstract
Diverse functions of eukaryotic cells are optimized by organization of compatible chemistries into distinct compartments defined by the structures of lipid-containing membranes, multiprotein complexes and oligomeric structures of saccharides and nucleic acids. This structural and chemical organization is coordinated, in part, through cysteine residues of proteins which undergo reversible oxidation-reduction and serve as chemical/structural transducing elements. The central thiol/disulfide redox couples, thioredoxin-1, thioredoxin-2, GSH/GSSG and cysteine/cystine (Cys/CySS), are not in equilibrium with each other and are maintained at distinct, non-equilibrium potentials in mitochondria, nuclei, the secretory pathway and the extracellular space. Mitochondria contain the most reducing compartment, have the highest rates of electron transfer and are highly sensitive to oxidation. Nuclei also have more reduced redox potentials but are relatively resistant to oxidation. The secretory pathway contains oxidative systems which introduce disulfides into proteins for export. The cytoplasm contains few metabolic oxidases and this maintains an environment for redox signaling dependent upon NADPH oxidases and NO synthases. Extracellular compartments are maintained at stable oxidizing potentials. Controlled changes in cytoplasmic GSH/GSSG redox potential are associated with functional state, varying with proliferation, differentiation and apoptosis. Variation in extracellular Cys/CySS redox potential is also associated with proliferation, cell adhesion and apoptosis. Thus, cellular redox biology is inseparable from redox compartmentalization. Further elucidation of the redox control networks within compartments will improve the mechanistic understanding of cell functions and their disruption in disease.
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Affiliation(s)
- Young-Mi Go
- Emory Clinical Biomarkers Laboratory and Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, Atlanta GA 30322, USA
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Gottesfeld JM. Small molecules affecting transcription in Friedreich ataxia. Pharmacol Ther 2007; 116:236-48. [PMID: 17826840 PMCID: PMC2080619 DOI: 10.1016/j.pharmthera.2007.06.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Accepted: 06/25/2007] [Indexed: 12/21/2022]
Abstract
This review concerns the development of small molecule therapeutics for the inherited neurodegenerative disease Friedreich ataxia (FRDA). FRDA is caused by transcriptional repression of the nuclear FXN gene, encoding the essential mitochondrial protein frataxin and accompanying loss of frataxin protein. Frataxin insufficiency leads to mitochrondrial dysfunction and progressive neurodegeneration, along with scoliosis, diabetes and cardiomyopathy. Individuals with FRDA generally die in early adulthood from the associated heart disease, the most common cause of death in FRDA. While antioxidants and iron chelators have shown promise in ameliorating the symptoms of the disease, there is no effective therapy for FRDA that addresses the cause of the disease, the loss of frataxin protein. Gene therapy and protein replacement strategies for FRDA are promising approaches; however, current technology is not sufficiently advanced to envisage treatments for FRDA coming from these approaches in the near future. Since the FXN mutation in FRDA, expanded GAA.TTC triplets in an intron, does not alter the amino acid sequence of frataxin protein, gene reactivation would be of therapeutic benefit. Thus, a number of laboratories have focused on small molecule activators of FXN gene expression as potential therapeutics, and this review summarizes the current status of these efforts, as well as the molecular basis for gene silencing in FRDA.
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Affiliation(s)
- Joel M Gottesfeld
- Department of Molecular Biology, MB-27, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA.
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Muller FL, Lustgarten MS, Jang Y, Richardson A, Van Remmen H. Trends in oxidative aging theories. Free Radic Biol Med 2007; 43:477-503. [PMID: 17640558 DOI: 10.1016/j.freeradbiomed.2007.03.034] [Citation(s) in RCA: 783] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 03/29/2007] [Accepted: 03/29/2007] [Indexed: 12/11/2022]
Abstract
The early observations on the rate-of-living theory by Max Rubner and the report by Gershman that oxygen free radicals exist in vivo culminated in the seminal proposal in the 1950s by Denham Harman that reactive oxygen species are a cause of aging (free radical theory of aging). The goal of this review is to analyze recent findings relevant in evaluating Harman's theory using experimental results as grouped by model organisms (i.e., invertebrate models and mice). In this regard, we have focused primarily on recent work involving genetic manipulations. Because the free radical theory of aging is not the only theorem proposed to explain the mechanism(s) involved in aging at the molecular level, we also discuss how this theory is related to other areas of research in biogerontology, specifically, telomere/cell senescence, genomic instability, and the mitochondrial hypothesis of aging. We also discuss where we think the free radical theory is headed. It is now possible to give at least a partial answer to the question whether oxidative stress determines life span as Harman posed so long ago. Based on studies to date, we argue that a tentative case for oxidative stress as a life-span determinant can be made in Drosophila melanogaster. Studies in mice argue for a role of oxidative stress in age-related disease, especially cancer; however, with regard to aging per se, the data either do not support or remain inconclusive on whether oxidative stress determines life span.
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Affiliation(s)
- Florian L Muller
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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Trushina E, McMurray CT. Oxidative stress and mitochondrial dysfunction in neurodegenerative diseases. Neuroscience 2007; 145:1233-48. [PMID: 17303344 DOI: 10.1016/j.neuroscience.2006.10.056] [Citation(s) in RCA: 323] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 10/24/2006] [Accepted: 10/27/2006] [Indexed: 11/16/2022]
Abstract
In recent years, it has become increasingly clear that mitochondrial dysfunction and oxidative damage are major contributors to neuronal loss. Free radicals, typically generated from mitochondrial respiration, cause oxidative damage of nucleic acids, lipids, carbohydrates and proteins. Despite enormous amount of effort, however, the mechanism by which oxidative damage causes neuronal death is not well understood. Emerging data from a number of neurodegenerative diseases suggest that there may be common features of toxicity that are related to oxidative damage. In this review, while focusing on Huntington's disease (HD), we discuss similarities among HD, Friedreich ataxia and xeroderma pigmentosum, which provide insight into shared mechanisms of neuronal death.
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Affiliation(s)
- E Trushina
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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Maliandi MV, Busi MV, Clemente M, Zabaleta EJ, Araya A, Gomez-Casati DF. Expression and one-step purification of recombinant Arabidopsis thaliana frataxin homolog (AtFH). Protein Expr Purif 2007; 51:157-61. [PMID: 16879981 DOI: 10.1016/j.pep.2006.06.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Revised: 06/09/2006] [Accepted: 06/09/2006] [Indexed: 11/15/2022]
Abstract
Frataxin, a nuclear-encoded mitochondrial protein, has been proposed to participate in Fe-S cluster assembly, mitochondrial energy metabolism, respiration, and iron homeostasis. However, its precise function remains elusive. Frataxin is highly conserved in living organisms with no major structural changes, in particular at the C-terminal protein domain, suggesting that it plays a key function in all organisms. Recently, a plant gene, AtFH, with significant homology to other members of the frataxin family has been described. To gain insight on the frataxin role in plants, the frataxin domain was expressed in Escherichia coli BL21-codonPlus (DE3)-RIL cells and purified using a Ni-chelating column. The purified protein, added to a mixture containing Fe(II) and H2O2, attenuates the Fenton reaction indicating that the recombinant plant frataxin is functional. The procedure described here produced high yield of 99% pure protein through only one chromatographic step, suitable for further structure-function studies.
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