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Zhao X, Yu M, Zhang W, Hou Y, Yuan Y, Wang Z. Demographic characteristics, diagnostic challenges, treatment patterns, and caregiver burden of mitochondrial diseases: a retrospective cross-sectional study. Orphanet J Rare Dis 2024; 19:287. [PMID: 39095827 PMCID: PMC11297657 DOI: 10.1186/s13023-024-03289-5] [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: 02/06/2024] [Accepted: 07/14/2024] [Indexed: 08/04/2024] Open
Abstract
BACKGROUND This study aimed to explore the demographic characteristics, diagnostic challenges, treatment patterns, and caregiver burden of mitochondrial diseases. METHODS This retrospective cross-sectional study enrolled patients diagnosed with mitochondrial diseases from the Department of Neurology at Peking University First Hospital between January 2010 and December 2021. A questionnaire covering demographic characteristics, diagnostic dilemma, treatment, economic aspects, and caregiver stress was administered, and disability was assessed using the modified Rankin Scale (mRS). RESULTS A total of 183 patients (mean age: 16 (IQR: 12-25), 49.72% males) were enrolled, including 124 pediatric patients and 59 adult patients. MELAS (106. 57.92%) and Leigh syndrome (37, 20.22%) were predominant among the mitochondrial disease subtypes. Among them, 132 (72.13%) patients were initially misdiagnosed with other diseases, 58 (31.69%) patients visited 2 hospitals before confirmed as mitochondrial disease, and 39 (21.31%) patients visited 3 hospitals before confirmed as mitochondrial disease. Metabolic modifiers were the most common type of drugs used, including several dietary supplements such as L-carnitine (117, 63.93%), Coenzyme Q10 (102, 55.74%), idebenone (82, 44.81%), and vitamins (99, 54.10%) for proper mitochondrial function. Mothers are the primary caregivers for both children (36.29%) and adults (38.98%). The mRS score ranged from 0 to 5, 92.35% of the patients had different degrees of disability due to mitochondrial disease. The average monthly treatment cost was 3000 RMB for children and 3100 RMB for adults. CONCLUSIONS This study provided valuable insights into the characteristics and challenges of mitochondrial diseases, which underscores the need for improved awareness, diagnostic efficiency, and comprehensive support for patients and caregivers.
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Affiliation(s)
- Xutong Zhao
- Department of Neurology, Beijing Jishuitan Hospital, Capital Medical University, Beijing, 102208, China
| | - Meng Yu
- Department of Neurology, Peking University First Hospital, Beijing, 100034, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, Beijing, 100034, China
| | - Yue Hou
- Department of Geriatrics, Peking University First Hospital, Beijing, 100034, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, 100034, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, Beijing, 100034, China.
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2
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Liu L, Yang J, Otani Y, Shiga T, Yamaguchi A, Oda Y, Hattori M, Goto T, Ishibashi S, Kawashima-Sonoyama Y, Ishihara T, Matsuzaki Y, Akamatsu W, Fujitani M, Taketani T. MELAS-Derived Neurons Functionally Improve by Mitochondrial Transfer from Highly Purified Mesenchymal Stem Cells (REC). Int J Mol Sci 2023; 24:17186. [PMID: 38139018 PMCID: PMC10742994 DOI: 10.3390/ijms242417186] [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: 11/17/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episode (MELAS) syndrome, caused by a single base substitution in mitochondrial DNA (m.3243A>G), is one of the most common maternally inherited mitochondrial diseases accompanied by neuronal damage due to defects in the oxidative phosphorylation system. There is no established treatment. Our previous study reported a superior restoration of mitochondrial function and bioenergetics in mitochondria-deficient cells using highly purified mesenchymal stem cells (RECs). However, whether such exogenous mitochondrial donation occurs in mitochondrial disease models and whether it plays a role in the recovery of pathological neuronal functions is unknown. Here, utilizing induced pluripotent stem cells (iPSC), we differentiated neurons with impaired mitochondrial function from patients with MELAS. MELAS neurons and RECs/mesenchymal stem cells (MSCs) were cultured under contact or non-contact conditions. Both RECs and MSCs can donate mitochondria to MELAS neurons, but RECs are more excellent than MSCs for mitochondrial transfer in both systems. In addition, REC-mediated mitochondrial transfer significantly restored mitochondrial function, including mitochondrial membrane potential, ATP/ROS production, intracellular calcium storage, and oxygen consumption rate. Moreover, mitochondrial function was maintained for at least three weeks. Thus, REC-donated exogenous mitochondria might offer a potential therapeutic strategy for treating neurological dysfunction in MELAS.
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Affiliation(s)
- Lu Liu
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
| | - Jiahao Yang
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
| | - Yoshinori Otani
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (Y.O.); (M.F.)
| | - Takahiro Shiga
- Center for Genomic and Regenerative Medicine, School of Medicine, Juntendo University, Tokyo 113-8421, Japan; (T.S.); (A.Y.); (W.A.)
| | - Akihiro Yamaguchi
- Center for Genomic and Regenerative Medicine, School of Medicine, Juntendo University, Tokyo 113-8421, Japan; (T.S.); (A.Y.); (W.A.)
| | - Yasuaki Oda
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
| | - Miho Hattori
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
| | - Tsukimi Goto
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
- Clinical Laboratory Division, Shimane University Hospital, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Shuichi Ishibashi
- Department of Digestive and General Surgery, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan;
| | - Yuki Kawashima-Sonoyama
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
| | - Takaya Ishihara
- Department of Life Science, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (T.I.); (Y.M.)
| | - Yumi Matsuzaki
- Department of Life Science, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (T.I.); (Y.M.)
| | - Wado Akamatsu
- Center for Genomic and Regenerative Medicine, School of Medicine, Juntendo University, Tokyo 113-8421, Japan; (T.S.); (A.Y.); (W.A.)
| | - Masashi Fujitani
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (Y.O.); (M.F.)
| | - Takeshi Taketani
- Department of Pediatrics, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan; (L.L.); (J.Y.); (Y.O.); (M.H.); (T.G.); (Y.K.-S.)
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Meng L, Wu G. Recent advances in small molecules for improving mitochondrial disorders. RSC Adv 2023; 13:20476-20485. [PMID: 37435377 PMCID: PMC10331567 DOI: 10.1039/d3ra03313a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/03/2023] [Indexed: 07/13/2023] Open
Abstract
Mitochondrial disorders are observed in various human diseases, including rare genetic disorders and complex acquired pathologies. Recent advances in molecular biological techniques have dramatically expanded the understanding of multiple pathomechanisms involving mitochondrial disorders. However, the therapeutic methods for mitochondrial disorders are limited. For this reason, there is increasing interest in identifying safe and effective strategies to mitigate mitochondrial impairments. Small-molecule therapies hold promise for improving mitochondrial performance. This review focuses on the latest advances in developing bioactive compounds for treating mitochondrial disease, aiming to provide a broader perspective of fundamental studies that have been carried out to evaluate the effects of small molecules in regulating mitochondrial function. Novel-designed small molecules ameliorating mitochondrial functions are urgent for further research.
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Affiliation(s)
- Liying Meng
- Department of Central Laboratory and Mitochondrial Medicine Laboratory, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University Qingdao China
| | - Guanzhao Wu
- Department of Central Laboratory and Mitochondrial Medicine Laboratory, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University Qingdao China
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4
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Guerrero-Molina MP, Morales-Conejo M, Delmiro A, Morán M, Domínguez-González C, Arranz-Canales E, Ramos-González A, Arenas J, Martín MA, de la Aleja JG. High-dose oral glutamine supplementation reduces elevated glutamate levels in cerebrospinal fluid in patients with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome. Eur J Neurol 2023; 30:538-547. [PMID: 36334048 DOI: 10.1111/ene.15626] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 10/07/2022] [Accepted: 10/27/2022] [Indexed: 11/08/2022]
Abstract
BACKGROUND AND PURPOSE Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome is a genetically heterogeneous disorder caused by mitochondrial DNA mutations. There are no disease-modifying therapies, and treatment remains mainly supportive. It has been shown previously that patients with MELAS syndrome have significantly increased cerebrospinal fluid (CSF) glutamate and significantly decreased CSF glutamine levels compared to controls. Glutamine has many metabolic fates in neurons and astrocytes, and the glutamate-glutamine cycle couples with many metabolic pathways depending on cellular requirements. The aim was to compare CSF glutamate and glutamine levels before and after dietary glutamine supplementation. It is postulated that high-dose oral glutamine supplementation could reduce the increase in glutamate levels. METHOD This open-label, single-cohort study determined the safety and changes in glutamate and glutamine levels in CSF after 12 weeks of oral glutamine supplementation. RESULTS Nine adult patients with MELAS syndrome (66.7% females, mean age 35.8 ± 3.2 years) were included. After glutamine supplementation, CSF glutamate levels were significantly reduced (9.77 ± 1.21 vs. 18.48 ± 1.34 μmol/l, p < 0.001) and CSF glutamine levels were significantly increased (433.66 ± 15.31 vs. 336.31 ± 12.92 μmol/l, p = 0.002). A side effect observed in four of nine patients was a mild sensation of satiety. One patient developed mild and transient elevation of transaminases, and another patient was admitted for an epileptic status without stroke-like episode. DISCUSSION This study demonstrates that high-dose oral glutamine supplementation significantly reduces CSF glutamate and increases CSF glutamine levels in patients with MELAS syndrome. These findings may have potential therapeutic implications in these patients. TRIAL REGISTRATION INFORMATION ClinicalTrials.gov Identifier: NCT04948138. Initial release 24 June 2021, first patient enrolled 1 July 2021. https://clinicaltrials.gov/ct2/show/NCT04948138.
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Affiliation(s)
| | - Montserrat Morales-Conejo
- Department of Internal Medicine, University Hospital, Madrid, Spain
- National Reference Center for Congenital Errors of Metabolism (CSUR) and European Reference Center for Inherited Metabolic Disease (MetabERN), University Hospital, Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
| | - Aitor Delmiro
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
- Research Institute ('imas12'), University Hospital, Madrid, Spain
| | - María Morán
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
- Research Institute ('imas12'), University Hospital, Madrid, Spain
| | - Cristina Domínguez-González
- Neurology Department, Neuromuscular Disorders Unit, University Hospital, Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
- Research Institute ('imas12'), University Hospital, Madrid, Spain
| | - Elena Arranz-Canales
- Department of Internal Medicine, University Hospital, Madrid, Spain
- National Reference Center for Congenital Errors of Metabolism (CSUR) and European Reference Center for Inherited Metabolic Disease (MetabERN), University Hospital, Madrid, Spain
| | | | - Joaquín Arenas
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
- Research Institute ('imas12'), University Hospital, Madrid, Spain
| | - Miguel A Martín
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), Madrid, Spain
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
- Research Institute ('imas12'), University Hospital, Madrid, Spain
| | - Jesús González de la Aleja
- National Reference Center for Congenital Errors of Metabolism (CSUR) and European Reference Center for Inherited Metabolic Disease (MetabERN), University Hospital, Madrid, Spain
- Neurology Department, Epilepsy Unit, University Hospital, Madrid, Spain
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5
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Russell MW, Muste JC, Seth K, Kumar M, Rich CA, Singh RP, Traboulsi EI. Functional imaging of mitochondria in genetically confirmed retinal dystrophies using flavoprotein fluorescence. Ophthalmic Genet 2022; 43:834-840. [PMID: 36384402 DOI: 10.1080/13816810.2022.2144903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Whether by indirect oxidative stress or direct genetic defect, various genetic retinal dystrophies involve mitochondrial stress. Mitochondrial flavoprotein fluorescence (FPF), reported as either average signal intensity or variability (heterogeneity), may serve as a direct, quantifiable marker of oxidative stress. MATERIALS AND METHODS This observational study enrolled patients with genetically confirmed retinal dystrophies between January and December 2021. Patients with concomitant maculopathy and ocular hypertension were excluded. Patients were FPF imaged with OcuMet Beacon® third generation device during routine outpatient visit. RESULTS The final analysis cohort included 242 images from 157 patients. Mean FPF intensity was significantly increased between age matched controls and patients with confirmed rod-cone dystrophy, Stargardt disease, Bardet-Biedl syndrome (BBS), and Mitochondrial ATP synthase mutation (P ≤ 0.007). Mean FPF heterogeneity was significantly increased between age matched controls and patients with confirmed rod-cone dystrophy, Stargardt disease, and BBS (P ≤ 0.011). FPF lesions were noted to correlate with Fundus Autofluorescence (FAF) lesions in diseases examined. CONCLUSIONS FPF intensity and heterogeneity significantly increased in patients with retinal dystrophies. The correlation of FPF lesions with FAF lesions implies FPF may be a clinically useful biomarker in patients with IRDs.
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Affiliation(s)
- Matthew W Russell
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Department of Education, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio, USA
| | - Justin C Muste
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Cleveland Clinic, Cole Eye Institute, Cleveland, Ohio, USA
| | - Kanika Seth
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Madhukar Kumar
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Department of Education, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | | | - Rishi P Singh
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA
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6
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Diao SP, Chen SF, Liu AQ, Zhou ZH, Peng ZX, Hong MF. Elderly onset of MELAS in a male: A case report. Front Neurol 2022; 13:1018529. [PMID: 36530638 PMCID: PMC9751332 DOI: 10.3389/fneur.2022.1018529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 11/09/2022] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is one of the most common maternally inherited mitochondrial diseases which rarely affects elderly people. CASE PRESENTATION We reported the case of a 61-year-old male patient with MELAS. He was experiencing acute migraine-like headaches as the first symptoms. Laboratory data showed elevated lactate and creatine kinase levels. Brain magnetic resonance imaging (MRI) found a high signal intensity lesion in the left occipital-temporal-parietal lobe on diffusion-weighted imaging (DWI). Magnetic resonance angiography (MRA) revealed reversible vasoconstriction of the middle cerebral arteries and superficial temporal arteries. A muscle biopsy suggested minor muscle damage. A genetic study revealed a mitochondrial DNA A3243G mutation. CONCLUSION Elderly onset of MELAS is rare and easily misdiagnosed as an ischemic stroke. MELAS with the onset of stroke-like episodes should be considered in adult or elderly patients with imaging findings that are atypical for cerebral infarction. The use of multimodal MRI in the clinical diagnosis of MELAS could be extremely beneficial.
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Affiliation(s)
| | | | | | | | | | - Ming-Fan Hong
- Department of Neurology, College of Clinical Medicine, The First Affiliated Hospital, Guangdong Pharmaceutical University, Guangzhou, China
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7
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Muacevic A, Adler JR, Insuasti W, Garofalo G, Aguirre AS, Encalada S, Villamarin J, Oña S, Tenemaza MG, Eissa-Garcés A, Matcheswalla S, Ortiz JF. Arginine for the Treatment of Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes: A Systematic Review. Cureus 2022; 14:e32709. [PMID: 36686069 PMCID: PMC9848692 DOI: 10.7759/cureus.32709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2022] [Indexed: 12/23/2022] Open
Abstract
Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disease that lacks a definitive treatment. Lately, there has been an increased interest in the scientific community about the role of arginine in the short and long-term settings of the disease. We aim to conduct a systematic review of the clinical use of arginine in the management of MELAS and explore the role of arginine in the pathophysiology of the disease. We used PubMed advanced-strategy searches and only included full-text clinical trials on humans written in the English language. After applying the inclusion/exclusion criteria, four clinical trials were reviewed. We used the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol for this systematic review. We used the Cochrane Collaboration risk-of-bias tool to assess the bias encountered in each study. Overall, IV arginine seems to be effective in improving symptoms during acute attacks of MELAS, while oral arginine supplementation increases endothelial function, preventing further stroke-like episodes.
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8
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Fan HC, Lee HF, Yue CT, Chi CS. Clinical Characteristics of Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-Like Episodes. Life (Basel) 2021; 11:life11111111. [PMID: 34832987 PMCID: PMC8617702 DOI: 10.3390/life11111111] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/11/2021] [Accepted: 10/16/2021] [Indexed: 12/12/2022] Open
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome, a maternally inherited mitochondrial disorder, is characterized by its genetic, biochemical and clinical complexity. The most common mutation associated with MELAS syndrome is the mtDNA A3243G mutation in the MT-TL1 gene encoding the mitochondrial tRNA-leu(UUR), which results in impaired mitochondrial translation and protein synthesis involving the mitochondrial electron transport chain complex subunits, leading to impaired mitochondrial energy production. Angiopathy, either alone or in combination with nitric oxide (NO) deficiency, further contributes to multi-organ involvement in MELAS syndrome. Management for MELAS syndrome is amostly symptomatic multidisciplinary approach. In this article, we review the clinical presentations, pathogenic mechanisms and options for management of MELAS syndrome.
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Affiliation(s)
- Hueng-Chuen Fan
- Department of Pediatrics, Tungs’ Taichung Metroharbor Hospital, Wuchi, Taichung 435, Taiwan; (H.-C.F.); (C.-T.Y.)
- Department of Medical Research, Tungs’ Taichung Metroharbor Hospital, Wuchi, Taichung 435, Taiwan
- Department of Rehabilitation, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli 356, Taiwan
- Department of Life Sciences, Agricultural Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan
| | - Hsiu-Fen Lee
- Department of Pediatrics, Taichung Veterans General Hospital, Taichung 407, Taiwan;
| | - Chen-Tang Yue
- Department of Pediatrics, Tungs’ Taichung Metroharbor Hospital, Wuchi, Taichung 435, Taiwan; (H.-C.F.); (C.-T.Y.)
| | - Ching-Shiang Chi
- Department of Pediatrics, Tungs’ Taichung Metroharbor Hospital, Wuchi, Taichung 435, Taiwan; (H.-C.F.); (C.-T.Y.)
- Correspondence: ; Tel.: +886-4-26581919-4301
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9
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Wang Y, Hu LF, Zhou TJ, Qi LY, Xing L, Lee J, Wang FZ, Oh YK, Jiang HL. Gene therapy strategies for rare monogenic disorders with nuclear or mitochondrial gene mutations. Biomaterials 2021; 277:121108. [PMID: 34478929 DOI: 10.1016/j.biomaterials.2021.121108] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 08/19/2021] [Accepted: 08/26/2021] [Indexed: 12/26/2022]
Abstract
Rare monogenic disorders are a group of single-gene-mutated diseases that have a low incidence rate (less than 0.5‰) and eventually lead to patient disability and even death. Due to the relatively low number of people affected, these diseases typically fail to attract a great deal of commercial investment and research interest, and the affected patients thus have unmet medical needs. Advances in genomics biology, gene editing, and gene delivery can now offer potentially effective options for treating rare monogenic diseases. Herein, we review the application of gene therapy strategies (traditional gene therapy and gene editing) against various rare monogenic diseases with nuclear or mitochondrial gene mutations, including eye, central nervous system, pulmonary, systemic, and blood cell diseases. We summarize their pathologic features, address the barriers to gene delivery for these diseases, discuss available therapies in the clinic and in clinical trials, and sum up in-development gene delivery systems for various rare monogenic disorders. Finally, we elaborate the possible directions and outlook of gene therapy for rare monogenic disorders.
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Affiliation(s)
- Yi Wang
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China
| | - Li-Fan Hu
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China
| | - Tian-Jiao Zhou
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China
| | - Lian-Yu Qi
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China
| | - Lei Xing
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China; State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Xinjiang Medical University, Urumqi, 830054, China
| | - Jaiwoo Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Feng-Zhen Wang
- Department of Clinical Pharmacy, The First Clinical School of Xuzhou Medical University, Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221006, China.
| | - Yu-Kyoung Oh
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
| | - Hu-Lin Jiang
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, China; State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Xinjiang Medical University, Urumqi, 830054, China; Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China.
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10
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Vassar R, Mehta N. Pearls & Oy-sters: Symmetric Numbness and Paresthesia Due to Stroke-like Episode in an Adolescent Male With MELAS. Neurology 2021; 97:1006-1008. [PMID: 34376513 DOI: 10.1212/wnl.0000000000012611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) syndrome is a mitochondrial condition with a wide range of neurologic complications including migraines, seizures, and stroke-like episodes. This case report highlights a rare presentation of bilateral sensory changes related to MELAS and offers an opportunity to consider how a differential diagnosis may need to be modified in patients with underlying mitochondrial disorders. Neurologic symptoms in MELAS may defy classic localization patterns, and early neuroimaging is warranted.
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Affiliation(s)
- Rachel Vassar
- Child Neurology Residency Program, Department of Neurology, University of California San Francisco, San Francisco, CA
| | - Nehali Mehta
- Child Neurology Residency Program, Department of Neurology, University of California San Francisco, San Francisco, CA
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11
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Panda PK, Sharawat IK, Singh A, Sherwani P. A Young Child with Recurrent Episodes of Headaches and Vision Loss: Diagnostic Clues? J Pediatr Neurosci 2021; 16:82-84. [PMID: 34316317 PMCID: PMC8276967 DOI: 10.4103/jpn.jpn_91_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/07/2020] [Accepted: 07/21/2020] [Indexed: 11/14/2022] Open
Abstract
MELAS is a mitochondrial cytopathy, with maternal inheritance and variable phenotype expression and severity depending on the degree of heteroplasmy. It presents with waxing and waning symptoms, in form of recurrent migrainous headache, transient loss of sight, hemianopsia, transient ischemic attack, or stroke-like episodes, focal seizures and even periods of altered sensorium. Here we present an 8-year-old boy presented with recurrent episodes of migrainous headache associated with vomiting sometimes and recurrent episodes of loss of vision for the past one year. As many of these episodes were precipitated by some febrile illness, so the child was suspected to have neurotuberculosis outside, because of Mantoux positivity. His mother also had similar episodes of recurrent headache and ultimately succumbed to cerebrovascular accident. Mitochondrial genome sequencing revealed heteroplasmic missense variation in the MT-TL1 gene (chrM:3243A>G).
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Affiliation(s)
- Prateek Kumar Panda
- Pediatric Neurology Division, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India
| | - Indar Kumar Sharawat
- Pediatric Neurology Division, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India
| | - Avinish Singh
- Pediatric Neurology Division, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India
| | - Poonam Sherwani
- Department of Radiology, All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India
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Esterhuizen K, Lindeque JZ, Mason S, van der Westhuizen FH, Rodenburg RJ, de Laat P, Smeitink JAM, Janssen MCH, Louw R. One mutation, three phenotypes: novel metabolic insights on MELAS, MIDD and myopathy caused by the m.3243A > G mutation. Metabolomics 2021; 17:10. [PMID: 33438095 DOI: 10.1007/s11306-020-01769-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/31/2020] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The m.3243A > G mitochondrial DNA mutation is one of the most common mitochondrial disease-causing mutations, with a carrier rate as high as 1:400. This point mutation affects the MT-TL1 gene, ultimately affecting the oxidative phosphorylation system and the cell's energy production. Strikingly, the m.3243A > G mutation is associated with different phenotypes, including mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), maternally inherited diabetes and deafness (MIDD) and myopathy. OBJECTIVES We investigated urine metabolomes of MELAS, MIDD and myopathy patients in order to identify affected metabolic pathways and possible treatment options. METHODS A multiplatform metabolomics approach was used to comprehensively analyze the metabolome and compare metabolic profiles of different phenotypes caused by the m.3243A > G mutation. Our analytical array consisted of NMR spectroscopy, LC-MS/MS and GC-TOF-MS. RESULTS The investigation revealed phenotypic specific metabolic perturbations, as well as metabolic similarities between the different phenotypes. We show that glucose metabolism is highly disturbed in the MIDD phenotype, but not in MELAS or myopathy, remodeled fatty acid oxidation is characteristic of the MELAS patients, while one-carbon metabolism is strongly modified in both MELAS and MIDD, but not in the myopathy group. Lastly we identified increased creatine in the urine of the myopathy patients, but not in MELAS or MIDD. CONCLUSION We conclude by giving novel insight on the phenotypes of the m.3243A > G mutation from a metabolomics point of view. Directives are also given for future investigations that could lead to better treatment options for patients suffering from this debilitating disease.
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Affiliation(s)
- Karien Esterhuizen
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - J Zander Lindeque
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - Shayne Mason
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | | | - Richard J Rodenburg
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Paul de Laat
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Jan A M Smeitink
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Mirian C H Janssen
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
- Department of Internal Medicine, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Roan Louw
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa.
- Human Metabolomics, Faculty of Natural and Agricultural Sciences, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom, South Africa.
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13
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Mitochondrial disorders and the eye. Surv Ophthalmol 2019; 65:294-311. [PMID: 31783046 DOI: 10.1016/j.survophthal.2019.11.001] [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] [Received: 05/15/2019] [Revised: 11/16/2019] [Accepted: 11/18/2019] [Indexed: 01/27/2023]
Abstract
Mitochondria are cellular organelles that play a key role in energy metabolism and oxidative phosphorylation. Malfunctioning of mitochondria has been implicated as the cause of many disorders with variable inheritance, heterogeneity of systems involved, and varied phenotype. Metabolically active tissues are more likely to be affected, causing an anatomic and physiologic disconnect in the treating physicians' mind between presentation and underlying pathophysiology. We shall focus on disorders of mitochondrial metabolism relevant to an ophthalmologist. These disorders can affect all parts of the visual pathway (crystalline lens, extraocular muscles, retina, optic nerve, and retrochiasm). After the introduction reviewing mitochondrial structure and function, each disorder is reviewed in detail, including approaches to its diagnosis and most current management guidelines.
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14
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Ellis S, Rang C, Kotsimbos T, Keating D, Finlayson F, Stark R, Thyagarajan D, Wilson J. CNS imaging studies in cystic fibrosis patients presenting with sudden neurological events. BMJ Open Respir Res 2019; 6:e000456. [PMID: 31423315 PMCID: PMC6688669 DOI: 10.1136/bmjresp-2019-000456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 12/15/2022] Open
Abstract
Background Acute neurological events may present as an extrapulmonary complication in patients with cystic fibrosis (CF). These events can be secondary to a range of different aetiologies. Methods A retrospective analysis of 476 medical records of CF patients attending a large teaching hospital between 2000 and 2018 was performed. Patients presenting with acute neurological events who had MRI brain imaging were evaluated. Patients who had headaches without associated neurological symptoms were excluded from this analysis. Results Acute neurological presentations, excluding headaches without associated neurological symptoms, were reported in 27 index patients out of the 476 patients. Of these, 16 patients had MRI brain imaging for review. Three patients suffered pathology secondary to vascular events, both ischaemic and haemorrhagic; four patients had evidence of ischaemia or infarction not consistent with a vascular territory stroke and the remaining patients experienced a range of different neurological events. The most common presentation among these patients was seizure activity, followed by a transient motor or sensory deficit. Conclusions Neurological complications are recognised among individuals with CF. Although rare, they can be secondary to a range of different aetiologies, including dysfunctional cell energetics. Additional studies are required to further evaluate this association.
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Affiliation(s)
- Samantha Ellis
- Department of Radiology, Alfred Health, Melbourne, Victoria, Australia
| | - Catherine Rang
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia
| | - Tom Kotsimbos
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
| | - Dominic Keating
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
| | - Felicity Finlayson
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia
| | - Richard Stark
- Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
| | | | - John Wilson
- Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.,Department of Medicine, Monash University, Melbourne, Victoria, Australia
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15
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Esterhuizen K, Lindeque JZ, Mason S, van der Westhuizen FH, Suomalainen A, Hakonen AH, Carroll CJ, Rodenburg RJ, de Laat PB, Janssen MC, Smeitink JA, Louw R. A urinary biosignature for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke like episodes (MELAS). Mitochondrion 2019; 45:38-45. [DOI: 10.1016/j.mito.2018.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 01/27/2018] [Accepted: 02/15/2018] [Indexed: 12/27/2022]
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16
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El-Hattab AW, Zarante AM, Almannai M, Scaglia F. Therapies for mitochondrial diseases and current clinical trials. Mol Genet Metab 2017; 122:1-9. [PMID: 28943110 PMCID: PMC5773113 DOI: 10.1016/j.ymgme.2017.09.009] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 09/14/2017] [Accepted: 09/14/2017] [Indexed: 01/10/2023]
Abstract
Mitochondrial diseases are a clinically and genetically heterogeneous group of disorders that result from dysfunction of the mitochondrial oxidative phosphorylation due to molecular defects in genes encoding mitochondrial proteins. Despite the advances in molecular and biochemical methodologies leading to better understanding of the etiology and mechanism of these diseases, there are still no satisfactory therapies available for mitochondrial disorders. Treatment for mitochondrial diseases remains largely symptomatic and does not significantly alter the course of the disease. Based on limited number of clinical trials, several agents aiming at enhancing mitochondrial function or treating the consequences of mitochondrial dysfunction have been used. Several agents are currently being evaluated for mitochondrial diseases. Therapeutic strategies for mitochondrial diseases include the use of agents enhancing electron transfer chain function (coenzyme Q10, idebenone, riboflavin, dichloroacetate, and thiamine), agents acting as energy buffer (creatine), antioxidants (vitamin C, vitamin E, lipoic acid, cysteine donors, and EPI-743), amino acids restoring nitric oxide production (arginine and citrulline), cardiolipin protector (elamipretide), agents enhancing mitochondrial biogenesis (bezafibrate, epicatechin, and RTA 408), nucleotide bypass therapy, liver transplantation, and gene therapy. Although, there is a lack of curative therapies for mitochondrial disorders at the current time, the increased number of clinical research evaluating agents that target different aspects of mitochondrial dysfunction is promising and is expected to generate more therapeutic options for these diseases in the future.
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Affiliation(s)
- Ayman W El-Hattab
- Division of Clinical Genetics and Metabolic Disorders, Pediatrics Department, Tawam Hospital, Al-Ain, United Arab Emirates
| | | | - Mohammed Almannai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA.
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El-Hattab AW, Almannai M, Scaglia F. Arginine and citrulline for the treatment of MELAS syndrome. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2017; 5:10.1177/2326409817697399. [PMID: 28736735 PMCID: PMC5519148 DOI: 10.1177/2326409817697399] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) syndrome is a maternally inherited mitochondrial disease with a broad spectrum of manifestations. In addition to impaired energy production, nitric oxide (NO) deficiency occurs in MELAS syndrome and leads to impaired blood perfusion in microvasculature that can contribute to several complications including stroke-like episodes, myopathy, and lactic acidosis. The supplementation of NO precursors, L-arginine and L-citrulline, increases NO production and hence can potentially have therapeutic utility in MELAS syndrome. L-citrulline raises NO production to a greater extent than L-arginine; therefore, L-citrulline may have a better therapeutic effect. The clinical effect of L-citrulline has not yet been studied and clinical studies on L-arginine, which are limited, only evaluated the stroke-like episodes aspect of the disease. Controlled studies are still needed to assess the clinical effects of L-arginine and L-citrulline on different aspects of MELAS syndrome.
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Affiliation(s)
- Ayman W. El-Hattab
- Division of Clinical Genetics and Metabolic Disorders, Pediatrics Department, Tawam Hospital, Al-Ain, United Arab Emirates
| | - Mohammed Almannai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
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18
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Cai SS, von Coelln R, Kouo TJ. Migratory stroke-like lesions in a case of adult-onset mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome and a review of imaging findings. Radiol Case Rep 2016; 11:425-429. [PMID: 27920873 PMCID: PMC5128397 DOI: 10.1016/j.radcr.2016.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/29/2016] [Accepted: 09/04/2016] [Indexed: 11/26/2022] Open
Abstract
Imaging findings of adult-onset mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is poorly documented. The authors present a 48-year-old woman with subacute onset of word-finding difficulties and right arm stiffness. Magnetic resonance imaging performed 2 weeks prior revealed left temporal lobe diffusion and fluid-attenuated inversion recovery hyperintensity predominantly involving the cortex. The apparent diffusion coefficient map showed preserved signal in the temporal cortex. Subsequent magnetic resonance imagings demonstrated a new diffusion signal abnormality extending to the left parietal cortex and occipital cortex with resolving diffusion hyperintensity in the temporal lobe. MR spectroscopy showed scattered areas of lactate deposition. Diagnosis of MELAS syndrome was confirmed by genetic analysis. Fluctuating, migratory stroke-like lesions with a predilection for the parietal, temporal, and occipital cortex that do not conform to a vascular territory and a lactate spike at 1.3 ppm on MR spectroscopy are characteristic of MELAS syndrome. Preserved signal intensity on apparent diffusion coefficient is useful to distinguish MELAS syndrome from ischemic infarction where the signal is typically reduced.
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Affiliation(s)
- Stephen S Cai
- Department of Radiology, University of Maryland School of Medicine, 22S. Green Street, Baltimore, MD 21201, USA
| | - Rainer von Coelln
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Theresa J Kouo
- Department of Radiology, University of Maryland School of Medicine, 22S. Green Street, Baltimore, MD 21201, USA
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19
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El-Hattab AW, Emrick LT, Hsu JW, Chanprasert S, Almannai M, Craigen WJ, Jahoor F, Scaglia F. Impaired nitric oxide production in children with MELAS syndrome and the effect of arginine and citrulline supplementation. Mol Genet Metab 2016; 117:407-12. [PMID: 26851065 PMCID: PMC4818739 DOI: 10.1016/j.ymgme.2016.01.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/26/2016] [Accepted: 01/26/2016] [Indexed: 11/29/2022]
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most frequent maternally inherited mitochondrial disorders. The pathogenesis of this syndrome is not fully understood and believed to result from several interacting mechanisms including impaired mitochondrial energy production, microvasculature angiopathy, and nitric oxide (NO) deficiency. NO deficiency in MELAS syndrome is likely to be multifactorial in origin with the decreased availability of the NO precursors, arginine and citrulline, playing a major role. In this study we used stable isotope infusion techniques to assess NO production in children with MELAS syndrome and healthy pediatric controls. We also assessed the effect of oral arginine and citrulline supplementations on NO production in children with MELAS syndrome. When compared to control subjects, children with MELAS syndrome were found to have lower NO production, arginine flux, plasma arginine, and citrulline flux. In children with MELAS syndrome, arginine supplementation resulted in increased NO production, arginine flux, and arginine concentration. Citrulline supplementation resulted in a greater increase of these parameters. Additionally, citrulline supplementation was associated with a robust increase in citrulline concentration and flux and de novo arginine synthesis rate. The greater effect of citrulline in increasing NO production is due to its greater ability to increase arginine availability particularly in the intracellular compartment in which NO synthesis takes place. This study, which is the first one to assess NO metabolism in children with mitochondrial diseases, adds more evidence to the notion that NO deficiency occurs in MELAS syndrome, suggests a better effect for citrulline because of its greater role as NO precursor, and indicates that impaired NO production occurs in children as well as adults with MELAS syndrome. Thus, the initiation of treatment with NO precursors may be beneficial earlier in life. Controlled clinical trials to assess the therapeutic effects of arginine and citrulline on clinical complications of MELAS syndrome are needed.
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Affiliation(s)
- Ayman W El-Hattab
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Division of Clinical Genetics and Metabolic Disorders, Pediatrics Department, Tawam Hospital, Al-Ain, United Arab Emirates
| | - Lisa T Emrick
- Division of Neurology and Developmental Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Jean W Hsu
- USDA/ARS Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
| | - Sirisak Chanprasert
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA
| | - Mohammed Almannai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA
| | - William J Craigen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA
| | - Farook Jahoor
- USDA/ARS Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA.
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Fryer RH, Bain J, De Vivo D. Mitochondrial Encephalomyopathy Lactic Acidosis and Stroke-Like Episodes (MELAS): A Case Report and Critical Reappraisal of Treatment Options. Pediatr Neurol 2016; 56:59-61. [PMID: 26797286 PMCID: PMC4789111 DOI: 10.1016/j.pediatrneurol.2015.12.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/15/2015] [Indexed: 01/31/2023]
Abstract
IMPORTANCE Stroke-like episodes signal progression and significant disability in the mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes syndrome. Arginine is widely used as a treatment for stroke-like episode, although there is little evidence for this intervention. We discuss the management of a patient with mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes who presented with a stroke-like episode. OBSERVATION During a seizure, which triggers the stroke-like episode, neurons are forced to utilize glycolysis as a source of adenosine triphosphate. Glycolytic by-products are damaging to the neuron. Breakdown of the blood-brain barrier leads to vasogenic edema. CONCLUSION Treatment of stroke-like episode should include anticonvulsants interictally to prevent seizures and dexamethasone ictally to help repair the blood-brain barrier.
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Affiliation(s)
- Robert H. Fryer
- Department of Neurology, Columbia University Medical Center, New York, NY,Corresponding Author: Robert H. Fryer, MD, PHD, 180 Fort Washington Avenue, Harkness 5th floor, New York, NY 10032, 212-342-2919 (P), 212-342-6865 (F),
| | - Jennifer Bain
- Department of Neurology, Columbia University Medical Center, New York, NY
| | - Darryl De Vivo
- Department of Neurology, Columbia University Medical Center, New York, NY
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Post-Transcriptional Modifications of RNA: Impact on RNA Function and Human Health. MODIFIED NUCLEIC ACIDS IN BIOLOGY AND MEDICINE 2016. [DOI: 10.1007/978-3-319-34175-0_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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22
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Garrido-Maraver J, Paz MV, Cordero MD, Bautista-Lorite J, Oropesa-Ávila M, de la Mata M, Pavón AD, de Lavera I, Alcocer-Gómez E, Galán F, Ybot González P, Cotán D, Jackson S, Sánchez-Alcázar JA. Critical role of AMP-activated protein kinase in the balance between mitophagy and mitochondrial biogenesis in MELAS disease. Biochim Biophys Acta Mol Basis Dis 2015; 1852:2535-53. [PMID: 26341273 DOI: 10.1016/j.bbadis.2015.08.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 08/03/2015] [Accepted: 08/31/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Juan Garrido-Maraver
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Marina Villanueva Paz
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Mario D Cordero
- Facultad de Odontología, Universidad de Sevilla, Sevilla, Spain
| | | | - Manuel Oropesa-Ávila
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Mario de la Mata
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Ana Delgado Pavón
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Isabel de Lavera
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Elizabet Alcocer-Gómez
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | | | - Patricia Ybot González
- Instituto de Biomedicina de Sevilla (IBIS)-CSIC, Hospital Virgen del Rocío, Sevilla, Spain
| | - David Cotán
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain
| | - Sandra Jackson
- Department of Neurology, Uniklinikum C. G. Carus, Dresden, Germany
| | - José A Sánchez-Alcázar
- Centro Andaluz de Biología del Desarrollo (CABD), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain; Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas, Sevilla 41013, Spain.
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El-Hattab AW, Adesina AM, Jones J, Scaglia F. MELAS syndrome: Clinical manifestations, pathogenesis, and treatment options. Mol Genet Metab 2015; 116:4-12. [PMID: 26095523 DOI: 10.1016/j.ymgme.2015.06.004] [Citation(s) in RCA: 352] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 06/14/2015] [Accepted: 06/14/2015] [Indexed: 12/13/2022]
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most frequent maternally inherited mitochondrial disorders. MELAS syndrome is a multi-organ disease with broad manifestations including stroke-like episodes, dementia, epilepsy, lactic acidemia, myopathy, recurrent headaches, hearing impairment, diabetes, and short stature. The most common mutation associated with MELAS syndrome is the m.3243A>G mutation in the MT-TL1 gene encoding the mitochondrial tRNA(Leu(UUR)). The m.3243A>G mutation results in impaired mitochondrial translation and protein synthesis including the mitochondrial electron transport chain complex subunits leading to impaired mitochondrial energy production. The inability of dysfunctional mitochondria to generate sufficient energy to meet the needs of various organs results in the multi-organ dysfunction observed in MELAS syndrome. Energy deficiency can also stimulate mitochondrial proliferation in the smooth muscle and endothelial cells of small blood vessels leading to angiopathy and impaired blood perfusion in the microvasculature of several organs. These events will contribute to the complications observed in MELAS syndrome particularly the stroke-like episodes. In addition, nitric oxide deficiency occurs in MELAS syndrome and can contribute to its complications. There is no specific consensus approach for treating MELAS syndrome. Management is largely symptomatic and should involve a multidisciplinary team. Unblinded studies showed that l-arginine therapy improves stroke-like episode symptoms and decreases the frequency and severity of these episodes. Additionally, carnitine and coenzyme Q10 are commonly used in MELAS syndrome without proven efficacy.
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Affiliation(s)
- Ayman W El-Hattab
- Division of Clinical Genetics and Metabolic Disorders, Department of Pediatrics, Tawam Hospital, Al-Ain, United Arab Emirates
| | - Adekunle M Adesina
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Jeremy Jones
- Singleton Department of Radiology, Texas Children's Hospital, Houston, TX, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
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24
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Swerdlow RH. Bioenergetic medicine. Br J Pharmacol 2014; 171:1854-69. [PMID: 24004341 DOI: 10.1111/bph.12394] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 08/17/2013] [Accepted: 08/22/2013] [Indexed: 12/12/2022] Open
Abstract
Here we discuss a specific therapeutic strategy we call 'bioenergetic medicine'. Bioenergetic medicine refers to the manipulation of bioenergetic fluxes to positively affect health. Bioenergetic medicine approaches rely heavily on the law of mass action, and impact systems that monitor and respond to the manipulated flux. Since classically defined energy metabolism pathways intersect and intertwine, targeting one flux also tends to change other fluxes, which complicates treatment design. Such indirect effects, fortunately, are to some extent predictable, and from a therapeutic perspective may also be desirable. Bioenergetic medicine-based interventions already exist for some diseases, and because bioenergetic medicine interventions are presently feasible, new approaches to treat certain conditions, including some neurodegenerative conditions and cancers, are beginning to transition from the laboratory to the clinic.
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Affiliation(s)
- Russell H Swerdlow
- Departments of Neurology, Molecular and Integrative Physiology, Biochemistry and Molecular Biology, University of Kansas School of Medicine, Kansas City, KS, USA; Alzheimer's Disease Center, University of Kansas Medical Center, Fairway, KS, USA
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Dindyal S, Mistry K, Angamuthu N, Smith G, Hilton D, Arumugam P, Mathew J. MELAS syndrome presenting as an acute surgical abdomen. Ann R Coll Surg Engl 2014; 96:101E-103E. [PMID: 24417855 PMCID: PMC5137644 DOI: 10.1308/003588414x13824511649733] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
MELAS (mitochondrial cytopathy, encephalomyopathy, lactic acidosis and stroke-like episodes) is a syndrome in which signs and symptoms of gastrointestinal disease are uncommon if not rare. We describe the case of a young woman who presented as an acute surgical emergency, diagnosed as toxic megacolon necessitating an emergency total colectomy. MELAS syndrome was suspected postoperatively owing to persistent lactic acidosis and neurological symptoms. The diagnosis was later confirmed with histological and genetic studies. This case highlights the difficulties in diagnosing MELAS because of its unpredictable presentation and clinical course. We therefore recommend a high index of suspicion in cases of an acute surgical abdomen with additional neurological features or raised lactate.
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Affiliation(s)
- S Dindyal
- 1Whittington Hospital NHS Trust, UK.
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El-Hattab AW, Emrick LT, Chanprasert S, Craigen WJ, Scaglia F. Mitochondria: Role of citrulline and arginine supplementation in MELAS syndrome. Int J Biochem Cell Biol 2014; 48:85-91. [DOI: 10.1016/j.biocel.2013.12.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/14/2013] [Accepted: 12/26/2013] [Indexed: 12/18/2022]
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El-Hattab AW, Emrick LT, Williamson KC, Craigen WJ, Scaglia F. The effect of citrulline and arginine supplementation on lactic acidemia in MELAS syndrome. Meta Gene 2013; 1:8-14. [PMID: 25411654 PMCID: PMC4205025 DOI: 10.1016/j.mgene.2013.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disorder in which nitric oxide (NO) deficiency may play a role in the pathogenesis of several complications including stroke-like episodes and lactic acidosis. Supplementing the NO precursors arginine and citrulline restores NO production in MELAS syndrome. In this study we evaluated the effect of arginine or citrulline on lactic acidemia in adults with MELAS syndrome. Plasma lactate decreased significantly after citrulline supplementation, whereas the effect of arginine supplementation did not reach statistical significance. These results support the potential therapeutic utility of arginine and citrulline in MELAS syndrome and suggest that citrulline supplementation may be more efficacious. However, therapeutic efficacy of these compounds should be further evaluated in clinical trials. MELAS syndrome is a common mitochondrial disease. Nitric oxide (NO) deficiency in MELAS may aggravate lactic acidosis. Arginine and citrulline are NO precursors and can restore NO production in MELAS. We assessed the effect of arginine and citrulline on lactate in adults with MELAS. Lactate decreased with citrulline or arginine with more reduction after citrulline.
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Affiliation(s)
- Ayman W El-Hattab
- Division of Medical Genetics, Department of Pediatrics, The Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia ; Faculty of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Lisa T Emrick
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Kaitlin C Williamson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - William J Craigen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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Selim L, Mehaney D. Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes in a Japanese child: Clinical, radiological and molecular genetic analysis. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2013. [DOI: 10.1016/j.ejmhg.2013.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Garrido-Maraver J, Cordero MD, Moñino ID, Pereira-Arenas S, Lechuga-Vieco AV, Cotán D, De la Mata M, Oropesa-Ávila M, De Miguel M, Bautista Lorite J, Rivas Infante E, Alvarez-Dolado M, Navas P, Jackson S, Francisci S, Sánchez-Alcázar JA. Screening of effective pharmacological treatments for MELAS syndrome using yeasts, fibroblasts and cybrid models of the disease. Br J Pharmacol 2013; 167:1311-28. [PMID: 22747838 DOI: 10.1111/j.1476-5381.2012.02086.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE MELAS (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) is a mitochondrial disease most usually caused by point mutations in tRNA genes encoded by mitochondrial DNA (mtDNA). Approximately 80% of cases of MELAS syndrome are associated with a m.3243A > G mutation in the MT-TL1 gene, which encodes the mitochondrial tRNALeu (UUR). Currently, no effective treatments are available for this chronic progressive disorder. Treatment strategies in MELAS and other mitochondrial diseases consist of several drugs that diminish the deleterious effects of the abnormal respiratory chain function, reduce the presence of toxic agents or correct deficiencies in essential cofactors. EXPERIMENTAL APPROACH We evaluated the effectiveness of some common pharmacological agents that have been utilized in the treatment of MELAS, in yeast, fibroblast and cybrid models of the disease. The yeast model harbouring the A14G mutation in the mitochondrial tRNALeu(UUR) gene, which is equivalent to the A3243G mutation in humans, was used in the initial screening. Next, the most effective drugs that were able to rescue the respiratory deficiency in MELAS yeast mutants were tested in fibroblasts and cybrid models of MELAS disease. KEY RESULTS According to our results, supplementation with riboflavin or coenzyme Q(10) effectively reversed the respiratory defect in MELAS yeast and improved the pathologic alterations in MELAS fibroblast and cybrid cell models. CONCLUSIONS AND IMPLICATIONS Our results indicate that cell models have great potential for screening and validating the effects of novel drug candidates for MELAS treatment and presumably also for other diseases with mitochondrial impairment.
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Affiliation(s)
- Juan Garrido-Maraver
- Centro Andaluz de Biología del Desarrollo (CABD) and Centro de Investigación Biomédica en Red: Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Sevilla, Spain
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Mkaouar-Rebai E, Chamkha I, Mezghani N, Ben Ayed I, Fakhfakh F. Screening of mitochondrial mutations in Tunisian patients with mitochondrial disorders: an overview study. ACTA ACUST UNITED AC 2013; 24:163-78. [PMID: 23301511 DOI: 10.3109/19401736.2012.748045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
To investigate the spectrum of common mitochondrial mutations in Tunisia during the years of 2002-2012, 226 patients with mitochondrial disorders were clinically diagnosed with hearing loss, Leigh syndrome (LS), diabetes, cardiomyopathy, Kearns-Sayre syndrome (KSS), Pearson syndrome (PS), myopathy, mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes syndrome (MELAS) and Wolfram syndrome. Restriction fragment length polymorphism (PCR-RFLP), radioactive PCR, single specific primer-PCR (SSP-PCR) analysis and PCR-sequencing methods were used to identify the mutations. Two cases with m.1555A>G mutation and two families with the novel 12S rRNA m.735A>G transition were detected in patients with hearing loss. Three cases with m.8993T>G mutation, two patients with the novel m.5523T>G and m.5559A>G mutations in the tRNA(Trp) gene, and two individuals with the undescribed m.9478T>C mutation in the cytochrome c oxidase subunit III (COXIII) gene were found with LS. In addition, one case with hypertrophic cardiomyopathy and deafness presented the ND1 m.3395A>G mutation and the tRNA(Ile) m.4316A>G variation. Besides, multiple mitochondrial deletions were detected in patients with KSS, PS, and Wolfram syndrome. The m.14709T>C mutation in the tRNA(Glu) was reported in four maternally inherited diabetes and deafness patients and a novel tRNA(Val) m.1640A>G mutation was detected in a MELAS patient.
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Affiliation(s)
- Emna Mkaouar-Rebai
- Human Molecular Genetic Laboratory, Faculty of Medicine of Sfax, Avenue Magida Boulila, 3029 Sfax, Tunisia.
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Steroid responsive A3243G mutation MELAS: clinical and radiographic evidence for regional hyperperfusion leading to neuronal loss. Neurologist 2012; 18:159-70. [PMID: 22549360 DOI: 10.1097/nrl.0b013e318247bcd8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a multisystem disorder caused by systemic cellular metabolic derangement that is characterized predominantly by rapidly progressive deterioration of the central nervous system. CASE REPORT We describe a patient with an abrupt onset of rapidly recurring episodes of aphasia, hemianopsia, and parietal pseudocerebellar ataxia, leading to the diagnosis of A3243G mutation MELAS. These stroke-like episodes appeared to be initiated by metabolic derangement, as evidenced by lactic-acid elevation in the cerebral spinal fluid and lactate peaks observed on magnetic resonance spectroscopy. Magnetic resonance imaging further revealed that neuronal loss during the acute episodes occurred in regions of paradoxically increased cerebral blood flow. Diffusion-tensor and arterial-spin-labeled perfusion imaging showed that the volume of tissue loss after the stroke-like episodes greatly exceeded the limits of the cortical areas affected by the initial metabolic insult. The patient was consented to a trial of compassionate use, high-dose intravenous corticosteroids, resulting in marked and sustained clinical improvement. CONCLUSIONS The majority of neurons lost in an acute episode are injured not by a primary failure to meet metabolic demand, but by a poorly regulated compensatory hyperperfusion response. Regional hyperperfusion leads to apoptotic cell death through a progression from vasogenic to cytotoxic edema. The efficacy of corticosteroids in our study patient demonstrates that inflammatory mediators and blood-brain barrier dysfunction may play a role in the pathophysiological cascade that leads to the regional hyperperfusion in MELAS.
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Bhuvaneswar CG, Goetz JL, Stern TA. Multiple neurologic, psychiatric, and endocrine complaints in a young woman: a case discussion and review of the clinical features and management of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke. PRIMARY CARE COMPANION TO THE JOURNAL OF CLINICAL PSYCHIATRY 2012; 10:237-44. [PMID: 18615168 DOI: 10.4088/pcc.v10n0309] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Muqtadar H, Testai FD. Single Gene Disorders Associated With Stroke: A Review and Update on Treatment Options. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2012; 14:288-97. [DOI: 10.1007/s11936-012-0179-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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34
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El-Hattab AW, Hsu JW, Emrick LT, Wong LJC, Craigen WJ, Jahoor F, Scaglia F. Restoration of impaired nitric oxide production in MELAS syndrome with citrulline and arginine supplementation. Mol Genet Metab 2012; 105:607-14. [PMID: 22325939 PMCID: PMC4093801 DOI: 10.1016/j.ymgme.2012.01.016] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 01/18/2012] [Accepted: 01/18/2012] [Indexed: 10/14/2022]
Abstract
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most common mitochondrial disorders. Although the pathogenesis of stroke-like episodes remains unclear, it has been suggested that mitochondrial proliferation may result in endothelial dysfunction and decreased nitric oxide (NO) availability leading to cerebral ischemic events. This study aimed to assess NO production in subjects with MELAS syndrome and the effect of the NO precursors arginine and citrulline. Using stable isotope infusion techniques, we assessed arginine, citrulline, and NO metabolism in control subjects and subjects with MELAS syndrome before and after arginine or citrulline supplementation. The results showed that subjects with MELAS had lower NO synthesis rate associated with reduced citrulline flux, de novo arginine synthesis rate, and plasma arginine and citrulline concentrations, and higher plasma asymmetric dimethylarginine (ADMA) concentration and arginine clearance. We conclude that the observed impaired NO production is due to multiple factors including elevated ADMA, higher arginine clearance, and, most importantly, decreased de novo arginine synthesis secondary to decreased citrulline availability. Arginine and, to a greater extent, citrulline supplementation increased the de novo arginine synthesis rate, the plasma concentrations and flux of arginine and citrulline, and NO production. De novo arginine synthesis increased markedly with citrulline supplementation, explaining the superior efficacy of citrulline in increasing NO production. The improvement in NO production with arginine or citrulline supplementation supports their use in MELAS and suggests that citrulline may have a better therapeutic effect than arginine. These findings can have a broader relevance for other disorders marked by perturbations in NO metabolism.
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Affiliation(s)
- Ayman W. El-Hattab
- Division of Medical Genetics, Department of Child Health, University of Missouri Health Care, One Hospital Drive, Columbia, MO, 65212, USA
| | - Jean W. Hsu
- US Department of Agriculture/Agricultural Research Service-Children’s Nutrition Research Center, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Lisa T. Emrick
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
- Texas Children’s Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | - Lee-Jun C. Wong
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - William J. Craigen
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
- Texas Children’s Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | - Farook Jahoor
- US Department of Agriculture/Agricultural Research Service-Children’s Nutrition Research Center, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
- Texas Children’s Hospital, 6621 Fannin Street, Houston, TX 77030, USA
- Corresponding author at: Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, MS BCM225, Houston, TX, 77030, USA. Fax: +1 832 825 4294. (F. Scaglia)
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Mezghani N, Mnif M, Kacem M, Mkaouar-Rebai E, Hadj Salem I, Kallel N, charfi N, Abid M, fakhfakh F. A whole mitochondrial genome screening in a MELAS patient: A novel mitochondrial tRNAVal mutation. Biochem Biophys Res Commun 2011; 407:747-52. [DOI: 10.1016/j.bbrc.2011.03.094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 03/18/2011] [Indexed: 10/18/2022]
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36
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Santa KM. Treatment options for mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome. Pharmacotherapy 2011; 30:1179-96. [PMID: 20973690 DOI: 10.1592/phco.30.11.1179] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare neurodegenerative disease caused by the decreased ability of cells to produce sufficient energy in the form of adenosine 5'-triphosphate. Although it is one of the most common maternally inherited mitochondrial disorders, its exact incidence is unknown. Caused most frequently by an A-to-G point mutation at the 3243 position in the mitochondrial DNA, MELAS syndrome has a broad range of clinical manifestations and a highly variable course. The classic neurologic characteristics include encephalopathy, seizures, and stroke-like episodes. In addition to its neurologic manifestations, MELAS syndrome exhibits multisystem effects including cardiac conduction defects, diabetes mellitus, short stature, myopathy, and gastrointestinal disturbances. Unfortunately, no consensus guidelines outlining standard drug regimens exist for this syndrome. Many of the accepted therapies used in treating MELAS syndrome have been identified through a small number of clinical trials or isolated case reports. Currently, the drugs most often used include antioxidants and various vitamins aimed at minimizing the demands on the mitochondria and supporting and maximizing their function. Some of the most frequently prescribed agents include coenzyme Q(10), l-arginine, B vitamins, and levocarnitine. Although articles describing MELAS syndrome are available, few specifically target education for clinical pharmacists. This article will provide pharmacists with a practical resource to enhance their understanding of MELAS syndrome in order to provide safe and effective pharmaceutical care.
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Affiliation(s)
- Kristin M Santa
- Department of Pharmacy, Froedtert Hospital, Milwaukee, Wisconsin 53226, USA.
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37
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Sanchez JM, Tan JA, Farmakiotis D, Aggarwal V. Atypical Strokes in a Young African American Male: A Case of Mitochondrial Encephalopathy Lactic Acidosis and Stroke-Like Episodes (MELAS) Syndrome. Stroke Res Treat 2011; 2011:140630. [PMID: 21789268 PMCID: PMC3140036 DOI: 10.4061/2011/140630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 05/04/2011] [Indexed: 11/26/2022] Open
Abstract
Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare but important cause of stroke-like symptoms which can often be missed Thambisetty and Newman 2004. We describe a case of a young male presenting with stroke-like episodes, later diagnosed with MELAS in an attempt to improve the understanding about diagnosing MELAS in the appropriate clinical context.
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Affiliation(s)
- Jully M. Sanchez
- Department of Internal Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Judy Ann Tan
- Department of Internal Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Dimitrios Farmakiotis
- Department of Internal Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Vikas Aggarwal
- Department of Internal Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
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MELAS syndrome associated with both A3243G-tRNALeu mutation and multiple mitochondrial DNA deletions. J Neurol Sci 2010; 296:101-3. [DOI: 10.1016/j.jns.2010.06.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 06/29/2010] [Accepted: 06/30/2010] [Indexed: 11/15/2022]
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39
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Successful left hemihepatectomy and perioperative management of a patient with biliary cystadenocarcinoma, complicated with MELAS syndrome: report of a case. Surg Today 2010; 40:878-82. [PMID: 20740354 DOI: 10.1007/s00595-009-4145-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 07/01/2009] [Indexed: 10/19/2022]
Abstract
Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like syndrome (MELAS) is a rare, fetal disease caused by a mutation in mitochondrial DNA that leads to impaired oxidative metabolism in skeletal muscle, the central nervous system, and liver function. This report presents the case of a 50-year-old woman with biliary cystadenocarcinoma complicated by MELAS who underwent a successful left hemihepatectomy. In this case, the diagnostic key for the malignant tumor was an (18)F-fluorodeoxyglucose positron emission tomography study, which was useful even in a patient with MELAS, which causes abnormal glucose metabolism. The perioperative management of such patients includes special precautions to prevent lactic acidosis and deterioration of the reserved liver function after a hepatectomy, since the mitochondrial function in MELAS patients is abnormal. The patient in this report has remained free of liver dysfunctions and cancer recurrence for 2 years following the hepatectomy. This is the first report of a successful major hepatectomy for a patient with MELAS.
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Kaufman KR, Zuber N, Rueda-Lara MA, Tobia A. MELAS with recurrent complex partial seizures, nonconvulsive status epilepticus, psychosis, and behavioral disturbances: case analysis with literature review. Epilepsy Behav 2010; 18:494-7. [PMID: 20580320 DOI: 10.1016/j.yebeh.2010.05.020] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 05/20/2010] [Accepted: 05/22/2010] [Indexed: 11/17/2022]
Abstract
Mitochondrial encephalopathy, lactic acidosis, and strokelike episodes (MELAS) is a progressive neurodegenerative disorder associated with polygenetic, maternally inherited, mitochondrial DNA mutations. MELAS has multisystem presentation including neurological, muscular, endocrine, auditory, visual, cardiac, psychiatric, renal, gastrointestinal and dermatological symptoms. Clinical course and prognosis are variable, often leading to cognitive decline, disability, and premature death. Both convulsive status epilepticus (CSE) and nonconvulsive status epilepticus (NCSE) are reported with MELAS. This report illustrates a case of MELAS with recurrent complex partial seizures, NCSE, confusion, aggressive behaviors, hallucinations, and paranoid delusions. Rapid video/EEG confirmation of diagnosis and aggressive antiepileptic drug intervention are required. Further education of medical professionals regarding this disorder, its appropriate management, and the significance of NCSE is indicated to avoid delay of treatment.
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Affiliation(s)
- Kenneth R Kaufman
- Department of Psychiatry, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA.
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41
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Scuderi C, Borgione E, Castello F, Lo Giudice M, Fichera M, Elia M, Amato C, Savio M, Di Blasi FD, Vitello GA, Romano S, DiMauro S, Musumeci SA. Coexistence of mitochondrial and nuclear DNA mutations in a woman with mitochondrial encephalomyopathy and double cortex. Mitochondrion 2010; 10:548-54. [PMID: 20433951 DOI: 10.1016/j.mito.2010.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 03/04/2010] [Accepted: 04/21/2010] [Indexed: 11/18/2022]
Abstract
We describe a 16-year-old girl with mental retardation, myoclonic epilepsy, ataxia, mitochondrial myopathy, sensorineural hearing loss, lactic acidosis, and MRI evidence of diffuse subcortical laminar heterotopia and agyria/pachygyria. Restriction fragment length polymorphism (RFLP) and DNA sequence analyses revealed two pathogenic mutations: a heteroplasmic m.3243A>G in muscle and blood, and a new heterozygous insertion at nt697 in the doublecortin gene (DCX), resulting in a frameshift after amino acid residue 232, with a premature stop codon at amino acid residue 244. This is yet another example of genetic "double trouble" resulting in a complex phenotype.
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Affiliation(s)
- Carmela Scuderi
- Unità Operativa di Malattie Neuromuscolari, IRCCS Oasi Maria SS, Troina, Italy.
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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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Abstract
OBJECTIVE The purpose of this manuscript is to review the various etiologies and to discuss the therapeutic issues in childhood stroke. METHODS A PubMed search of literature pertaining to childhood stroke was conducted from 1983 to 2008 using specific key search words pertinent to cerebrovascular disorders in childhood. RESULTS The analysis of the multiple causes of childhood stroke including arterial ischemic strokes and cerebral venous thrombosis was presented. Current therapy and outcome data in childhood stroke are also discussed throughout the length of the article. CONCLUSIONS With increasing vigilance among physicians and improved neuroimaging modalities, the diagnosis of childhood stroke is now made earlier, with increasing frequency and greater accuracy. However, larger and well-controlled studies regarding the optimal management of childhood stroke in terms of the use of both antithrombotic drugs and anticoagulation are still needed in addition to longitudinal follow-up studies of children with stroke.
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Affiliation(s)
- Rosario Maria S Riel-Romero
- Louisiana State University Health Sciences Center, School of Medicine in Shreveport, Shreveport, LA 71130, USA.
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45
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Muñoz-Guillén N, León-López R, Ferrer-Higueras MJ, Vargas-Vaserot FJ, Dueñas-Jurado JM. [Arreflexic coma and MELAS syndrome]. Rev Clin Esp 2009; 209:337-41. [PMID: 19709537 DOI: 10.1016/s0014-2565(09)71818-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
MELAS is a progressive neurodegenerative and fatal disease characterized by mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes. It is the result of a mitochondrial DNA mutation. Although the incidence of MELAS is currently unknown, it is suspected that approximately 1 out of every 5,000 persons world-wide have some type of defect in mitochondrial DNA. Cardinal clinical features observed in more than 90% of the patients include severe headache that may be associated with stroke-like episodes, seizures and the onset of symptoms before the age of 40 years. Diagnosis is established through genetic test or by with muscle biopsies that reveal the presence of ragged-red fibers. Prognosis is poor, with death at an early age. In this article, we present the clinical case of a 31-year old women diagnosed of MELAS syndrome who was admitted to the Intensive Care Unit of our hospital with arreflexic coma.
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Affiliation(s)
- N Muñoz-Guillén
- Servicio de Medicina Intensiva, Hospital Universitario Reina Sofía, Córdoba, España.
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46
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Katayama Y, Maeda K, Iizuka T, Hayashi M, Hashizume Y, Sanada M, Kawai H, Kashiwagi A. Accumulation of oxidative stress around the stroke-like lesions of MELAS patients. Mitochondrion 2009; 9:306-13. [PMID: 19393775 DOI: 10.1016/j.mito.2009.04.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 04/04/2009] [Accepted: 04/15/2009] [Indexed: 02/05/2023]
Abstract
To investigate the relationship between oxidative stress and progressive spread of the stroke-like lesions in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with 3243A>G mutation, we retrospectively analyzed the spread frequency in patients with and without treatment with the radical scavenger edaravone. Oxidative damage and defensive enzymes were histologically evaluated. Spread was significantly less frequent in the patients treated with edaravone. Although 8-hydroxy-2'-deoxyguanosine, a marker for oxidative damage of DNA, was obviously accumulated in peri-lesional surviving neurons, manganese superoxide dismutase and 8-oxoguanine glycosylase 1 were not up-regulated in those neurons. Increased oxidative stress and insufficient defense could be involved in the pathogenesis of the spreading lesions in MELAS.
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Affiliation(s)
- Yuri Katayama
- Division of Neurology, Department of Internal Medicine, Shiga University of Medical Science, Seta-Tsukinowa, Otsu, Shiga 520-2192, Japan
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Abstract
The association of genetic factors and cerebral infarction (CI) has long been established. A positive family history alone is a recognized risk factor for CI and vascular events in general. However, there are certain inherited conditions that further increase the risk of stroke. These conditions are generally metabolic and mitochondrial genetic defects that have variable modes of inheritance. This article reviews major inherited metabolic disorders that predispose an individual to CI. Ten main conditions will be discussed: Fabry's disease, cerebrotendinous xanthomatosis, tangier disease, familial hypercholesterolemia, homocystinuria, methylmalonic acidemia, glutaric aciduria type I, propionic acidemia, ornithine transcarbamylase deficiency and mitochondrial encephalopathy, lactic acidosis and stroke-like phenomenon.
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Affiliation(s)
- Kavita Kalidas
- Department of Neurology, University of South Florida College of Medicine, Tampa, FL 33606, USA.
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Rossmanith W, Freilinger M, Roka J, Raffelsberger T, Moser-Their K, Prayer D, Bernert G, Bittner R. Isolated cytochrome c oxidase deficiency as a cause of MELAS. BMJ Case Rep 2009; 2009:bcr08.2008.0666. [PMID: 21686692 PMCID: PMC3027970 DOI: 10.1136/bcr.08.2008.0666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Deletion of a single nucleotide (7630delT) within MT-CO2, the gene of subunit II of cytochrome c oxidase (COX), was identified in a clinically typical MELAS case. The deletion-induced frameshift results in a stop codon close to the 5' end of the reading frame. The lack of subunit II (COII) precludes the assembly of COX and leads to the degradation of unassembled subunits, even those not directly affected by the mutation. Despite mitochondrial proliferation and transcriptional upregulation of nuclear and mtDNA-encoded COX genes (including MT-CO2), a severe COX deficiency was found with all investigations of the muscle biopsy (histochemistry, biochemistry, immunoblotting). The 7630delT mutation in MT-CO2 leads to a lack of COII with subsequent misassembly and degradation of respiratory complex IV despite transcriptional upregulation of its subunits. The genetic and pathobiochemical heterogeneity of MELAS appears to be greater than previously appreciated.
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Affiliation(s)
- Walter Rossmanith
- Medical University of Vienna, Währinger Straße 13, Vienna, 1090, Austria
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Finsterer J. Cognitive decline as a manifestation of mitochondrial disorders (mitochondrial dementia). J Neurol Sci 2008; 272:20-33. [DOI: 10.1016/j.jns.2008.05.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 05/18/2008] [Accepted: 05/20/2008] [Indexed: 11/28/2022]
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