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Díaz-Castro F, Tuñón-Suárez M, Rivera P, Botella J, Cancino J, Figueroa AM, Gutiérrez J, Cantin C, Deldicque L, Zbinden-Foncea H, Nielsen J, Henríquez-Olguín C, Morselli E, Castro-Sepúlveda M. A single bout of resistance exercise triggers mitophagy, potentially involving the ejection of mitochondria in human skeletal muscle. Acta Physiol (Oxf) 2024:e14203. [PMID: 39023008 DOI: 10.1111/apha.14203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 06/17/2024] [Accepted: 07/04/2024] [Indexed: 07/20/2024]
Abstract
AIM The present study aimed to investigate the effects of a single bout of resistance exercise on mitophagy in human skeletal muscle (SkM). METHODS Eight healthy men were recruited to complete an acute bout of one-leg resistance exercise. SkM biopsies were obtained one hour after exercise in the resting leg (Rest-leg) and the contracting leg (Ex-leg). Mitophagy was assessed using protein-related abundance, transmission electron microscopy (TEM), and fluorescence microscopy. RESULTS Our results show that acute resistance exercise increased pro-fission protein phosphorylation (DRP1Ser616) and decreased mitophagy markers such as PARKIN and BNIP3L/NIX protein abundance in the Ex-leg. Additionally, mitochondrial complex IV decreased in the Ex-leg when compared to the Rest-leg. In the Ex-leg, TEM and immunofluorescence images showed mitochondrial cristae abnormalities, a mitochondrial fission phenotype, and increased mitophagosome-like structures in both subsarcolemmal and intermyofibrillar mitochondria. We also observed increased mitophagosome-like structures on the subsarcolemmal cleft and mitochondria in the extracellular space of SkM in the Ex-leg. We stimulated human primary myotubes with CCCP, which mimics mitophagy induction in the Ex-leg, and found that BNIP3L/NIX protein abundance decreased independently of lysosomal degradation. Finally, in another human cohort, we found a negative association between BNIP3L/NIX protein abundance with both mitophagosome-like structures and mitochondrial cristae density in the SkM. CONCLUSION The findings suggest that a single bout of resistance exercise can initiate mitophagy, potentially involving mitochondrial ejection, in human skeletal muscle. BNIP3L/NIX is proposed as a sensitive marker for assessing mitophagy flux in SkM.
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Affiliation(s)
- Francisco Díaz-Castro
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
- Physiology Department, Biological Science Faculty, Pontificia Universidad Católica de Chile, Santiago, Chile
- Laboratory of Autophagy and Metabolism, Department of Basic Sciences, Faculty of Medicine and Sciences, Universidad San Sebastián, Santiago, Chile
| | - Mauro Tuñón-Suárez
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Patricia Rivera
- Physiology Department, Biological Science Faculty, Pontificia Universidad Católica de Chile, Santiago, Chile
- Laboratory of Autophagy and Metabolism, Department of Basic Sciences, Faculty of Medicine and Sciences, Universidad San Sebastián, Santiago, Chile
| | - Javier Botella
- Department of Dermatology and Venereology, University Hospital of Lausanne, Lausanne, Switzerland
| | - Jorge Cancino
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Ana María Figueroa
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Juan Gutiérrez
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Claudette Cantin
- Departamento de Odontología, Facultad de Odontología y Ciencias de la Rehabilitación, Universidad San Sebastián, Puerto Montt, Chile
| | - Louise Deldicque
- Institute of Neuroscience, UCLouvain, Ottignies-Louvain-la-Neuve, Belgium
| | - Hermann Zbinden-Foncea
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
- Departamento de Fisioterapia, Facultad de Ciencias de la Salud, Universidad Francisco de Vitoria, Madrid, Spain
| | - Joachim Nielsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Carlos Henríquez-Olguín
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Copenhagen, Denmark
| | - Eugenia Morselli
- Laboratory of Autophagy and Metabolism, Department of Basic Sciences, Faculty of Medicine and Sciences, Universidad San Sebastián, Santiago, Chile
| | - Mauricio Castro-Sepúlveda
- Center of Exercise Physiology and Metabolism, Department of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
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Meyer C, Hertig D, Arnold J, Urzi C, Kurth S, Mayr JA, Schaller A, Vermathen P, Nuoffer JM. Complex I, V, and MDH2 deficient human skin fibroblasts reveal distinct metabolic signatures by 1 H HR-MAS NMR. J Inherit Metab Dis 2024; 47:270-279. [PMID: 38084664 DOI: 10.1002/jimd.12696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/02/2023] [Accepted: 11/24/2023] [Indexed: 12/30/2023]
Abstract
In this study, we investigated the metabolic signatures of different mitochondrial defects (two different complex I and complex V, and the one MDH2 defect) in human skin fibroblasts (HSF). We hypothesized that using a selective culture medium would cause defect specific adaptation of the metabolome and further our understanding of the biochemical implications for the studied defects. All cells were cultivated under galactose stress condition and compared to glucose-based cell culture condition. We investigated the bioenergetic profile using Seahorse XFe96 cell analyzer and assessed the extracellular metabolic footprints and the intracellular metabolic fingerprints using NMR. The galactose-based culture condition forced a bioenergetic switch from a glycolytic to an oxidative state in all cell lines which improved overall separation of controls from the different defect groups. The extracellular metabolome was discriminative for separating controls from defects but not the specific defects, whereas the intracellular metabolome suggests CI and CV changes and revealed clear MDH2 defect-specific changes in metabolites associated with the TCA cycle, malate aspartate shuttle, and the choline metabolism, which are pronounced under galactose condition.
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Affiliation(s)
- Christoph Meyer
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Damian Hertig
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
| | - Janine Arnold
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
| | - Christian Urzi
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Sandra Kurth
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
| | - Johannes A Mayr
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - André Schaller
- Department of Human Genetics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Peter Vermathen
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland
| | - Jean-Marc Nuoffer
- Institute of Clinical Chemistry, University Hospital Bern, Bern, Switzerland
- Department of Pediatric Endocrinology, Diabetology and Metabolism, University Children's Hospital of Bern, Bern, Switzerland
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3
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Huang Y, Ji W, Zhang J, Huang Z, Ding A, Bai H, Peng B, Huang K, Du W, Zhao T, Li L. The involvement of the mitochondrial membrane in drug delivery. Acta Biomater 2024; 176:28-50. [PMID: 38280553 DOI: 10.1016/j.actbio.2024.01.027] [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: 10/10/2023] [Revised: 12/23/2023] [Accepted: 01/18/2024] [Indexed: 01/29/2024]
Abstract
Treatment effectiveness and biosafety are critical for disease therapy. Bio-membrane modification facilitates the homologous targeting of drugs in vivo by exploiting unique antibodies or antigens, thereby enhancing therapeutic efficacy while ensuring biosafety. To further enhance the precision of disease treatment, future research should shift focus from targeted cellular delivery to targeted subcellular delivery. As the cellular powerhouses, mitochondria play an indispensable role in cell growth and regulation and are closely involved in many diseases (e.g., cancer, cardiovascular, and neurodegenerative diseases). The double-layer membrane wrapped on the surface of mitochondria not only maintains the stability of their internal environment but also plays a crucial role in fundamental biological processes, such as energy generation, metabolite transport, and information communication. A growing body of evidence suggests that various diseases are tightly related to mitochondrial imbalance. Moreover, mitochondria-targeted strategies hold great potential to decrease therapeutic threshold dosage, minimize side effects, and promote the development of precision medicine. Herein, we introduce the structure and function of mitochondrial membranes, summarize and discuss the important role of mitochondrial membrane-targeting materials in disease diagnosis/treatment, and expound the advantages of mitochondrial membrane-assisted drug delivery for disease diagnosis, treatment, and biosafety. This review helps readers understand mitochondria-targeted therapies and promotes the application of mitochondrial membranes in drug delivery. STATEMENT OF SIGNIFICANCE: Bio-membrane modification facilitates the homologous targeting of drugs in vivo by exploiting unique antibodies or antigens, thereby enhancing therapeutic efficacy while ensuring biosafety. Compared to cell-targeted treatment, targeting of mitochondria for drug delivery offers higher efficiency and improved biosafety and will promote the development of precision medicine. As a natural material, the mitochondrial membrane exhibits excellent biocompatibility and can serve as a carrier for mitochondria-targeted delivery. This review provides an overview of the structure and function of mitochondrial membranes and explores the potential benefits of utilizing mitochondrial membrane-assisted drug delivery for disease treatment and biosafety. The aim of this review is to enhance readers' comprehension of mitochondrial targeted therapy and to advance the utilization of mitochondrial membrane in drug delivery.
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Affiliation(s)
- Yinghui Huang
- The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen 361005, China
| | - Wenhui Ji
- The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen 361005, China
| | - Jiaxin Zhang
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
| | - Ze Huang
- The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen 361005, China; Future Display Institute in Xiamen, Xiamen 361005, China
| | - Aixiang Ding
- The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen 361005, China
| | - Hua Bai
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
| | - Bo Peng
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
| | - Kai Huang
- Future Display Institute in Xiamen, Xiamen 361005, China
| | - Wei Du
- School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, China.
| | - Tingting Zhao
- School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, China.
| | - Lin Li
- The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen 361005, China; Future Display Institute in Xiamen, Xiamen 361005, China.
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Sopariwala DH, Hao NTT, Narkar VA. Estrogen-related Receptor Signaling in Skeletal Muscle Fitness. Int J Sports Med 2023; 44:609-617. [PMID: 36787804 PMCID: PMC11168301 DOI: 10.1055/a-2035-8192] [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] [Indexed: 02/16/2023]
Abstract
Skeletal muscle is a highly plastic tissue that can alter its metabolic and contractile features, as well as regenerative potential in response to exercise and other conditions. Multiple signaling factors including metabolites, kinases, receptors, and transcriptional factors have been studied in the regulation of skeletal muscle plasticity. Recently, estrogen-related receptors (ERRs) have emerged as a critical transcriptional hub in control of skeletal muscle homeostasis. ERRα and ERRγ - the two highly expressed ERR sub-types in the muscle respond to various extracellular cues such as exercise, hypoxia, fasting and dietary factors, in turn regulating gene expression in the skeletal muscle. On the other hand, conditions such as diabetes and muscular dystrophy suppress expression of ERRs in the skeletal muscle, likely contributing to disease progression. We highlight key functions of ERRs in the skeletal muscle including the regulation of fiber type, mitochondrial metabolism, vascularization, and regeneration. We also describe how ERRs are regulated in the skeletal muscle, and their interaction with important muscle regulators (e. g. AMPK and PGCs). Finally, we identify critical gaps in our understanding of ERR signaling in the skeletal muscle, and suggest future areas of investigation to advance ERRs as potential targets for function promoting therapeutics in muscle diseases.
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Affiliation(s)
- Danesh H. Sopariwala
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | - Nguyen Thi Thu Hao
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | - Vihang A. Narkar
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center (UTHealth), Houston, TX, USA
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Sopariwala DH, Rios AS, Pei G, Roy A, Tomaz da Silva M, Thi Thu Nguyen H, Saley A, Van Drunen R, Kralli A, Mahan K, Zhao Z, Kumar A, Narkar VA. Innately expressed estrogen-related receptors in the skeletal muscle are indispensable for exercise fitness. FASEB J 2023; 37:e22727. [PMID: 36583689 DOI: 10.1096/fj.202201518r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/01/2022] [Accepted: 12/12/2022] [Indexed: 12/31/2022]
Abstract
Transcriptional determinants in the skeletal muscle that govern exercise capacity, while poorly defined, could provide molecular insights into how exercise improves fitness. Here, we have elucidated the role of nuclear receptors, estrogen-related receptor alpha and gamma (ERRα/γ) in regulating myofibrillar composition, contractility, and exercise capacity in skeletal muscle. We used muscle-specific single or double (DKO) ERRα/γ knockout mice to investigate the effect of ERRα/γ deletion on muscle and exercise parameters. Individual knockout of ERRα/γ did not have a significant impact on the skeletal muscle. On the other hand, DKO mice exhibit pale muscles compared to wild-type (WT) littermates. RNA-seq analysis revealed a predominant decrease in expression of genes linked to mitochondrial and oxidative metabolism in DKO versus WT muscles. DKO muscles exhibit marked repression of oxidative enzymatic capacity, as well as mitochondrial number and size compared to WT muscles. Mitochondrial function is also impaired in single myofibers isolated from DKO versus WT muscles. In addition, mutant muscles exhibit reduced angiogenic gene expression and decreased capillarity. Consequently, DKO mice have a significantly reduced exercise capacity, further reflected in poor fatigue resistance of DKO mice in in vivo contraction assays. These results show that ERRα and ERRγ together are a critical link between muscle aerobic capacity and exercise tolerance. The ERRα/γ mutant mice could be valuable for understanding the long-term impact of impaired mitochondria and vascular supply on the pathogenesis of muscle-linked disorders.
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Affiliation(s)
- Danesh H Sopariwala
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA
| | - Andrea S Rios
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA
| | - Guangsheng Pei
- Center for Precision Medicine, School of Biomedical Informatics, The University of Texas Health Science Center, Houston, Texas, USA
| | - Anirban Roy
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, Texas, USA
| | - Meiricris Tomaz da Silva
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, Texas, USA
| | - Hao Thi Thu Nguyen
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA
| | - Addison Saley
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA.,Department of Biosciences, Rice University, Houston, Texas, USA
| | - Rachel Van Drunen
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA
| | - Anastasia Kralli
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kristin Mahan
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA.,Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center, Houston, Texas, USA
| | - Zhongming Zhao
- Center for Precision Medicine, School of Biomedical Informatics, The University of Texas Health Science Center, Houston, Texas, USA.,Human Genetics Center, School of Public Health, The University of Texas Health Science Center, Houston, Texas, USA
| | - Ashok Kumar
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, Texas, USA
| | - Vihang A Narkar
- Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas, USA.,Graduate School of Biomedical Sciences at UTHealth, Houston, Texas, USA
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Statins Induce Locomotion and Muscular Phenotypes in Drosophila melanogaster That Are Reminiscent of Human Myopathy: Evidence for the Role of the Chloride Channel Inhibition in the Muscular Phenotypes. Cells 2022; 11:cells11223528. [PMID: 36428957 PMCID: PMC9688544 DOI: 10.3390/cells11223528] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/17/2022] [Accepted: 11/01/2022] [Indexed: 11/09/2022] Open
Abstract
The underlying mechanisms for statin-induced myopathy (SIM) are still equivocal. In this study, we employ Drosophila melanogaster to dissect possible underlying mechanisms for SIM. We observe that chronic fluvastatin treatment causes reduced general locomotion activity and climbing ability. In addition, transmission microscopy of dissected skeletal muscles of fluvastatin-treated flies reveals strong myofibrillar damage, including increased sarcomere lengths and Z-line streaming, which are reminiscent of myopathy, along with fragmented mitochondria of larger sizes, most of which are round-like shapes. Furthermore, chronic fluvastatin treatment is associated with impaired lipid metabolism and insulin signalling. Mechanistically, knockdown of the statin-target Hmgcr in the skeletal muscles recapitulates fluvastatin-induced mitochondrial phenotypes and lowered general locomotion activity; however, it was not sufficient to alter sarcomere length or elicit myofibrillar damage compared to controls or fluvastatin treatment. Moreover, we found that fluvastatin treatment was associated with reduced expression of the skeletal muscle chloride channel, ClC-a (Drosophila homolog of CLCN1), while selective knockdown of skeletal muscle ClC-a also recapitulated fluvastatin-induced myofibril damage and increased sarcomere lengths. Surprisingly, exercising fluvastatin-treated flies restored ClC-a expression and normalized sarcomere lengths, suggesting that fluvastatin-induced myofibrillar phenotypes could be linked to lowered ClC-a expression. Taken together, these results may indicate the potential role of ClC-a inhibition in statin-associated muscular phenotypes. This study underlines the importance of Drosophila melanogaster as a powerful model system for elucidating the locomotion and muscular phenotypes, promoting a better understanding of the molecular mechanisms underlying SIM.
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Magri F, Antognozzi S, Ripolone M, Zanotti S, Napoli L, Ciscato P, Velardo D, Scuvera G, Nicotra V, Giacobbe A, Milani D, Fortunato F, Garbellini M, Sciacco M, Corti S, Comi GP, Ronchi D. Megaconial congenital muscular dystrophy due to novel CHKB variants: a case report and literature review. Skelet Muscle 2022; 12:23. [PMID: 36175989 PMCID: PMC9524117 DOI: 10.1186/s13395-022-00306-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 09/17/2022] [Indexed: 11/10/2022] Open
Abstract
Background Choline kinase beta (CHKB) catalyzes the first step in the de novo biosynthesis of phosphatidyl choline and phosphatidylethanolamine via the Kennedy pathway. Derangement of this pathway might also influence the homeostasis of mitochondrial membranes. Autosomal recessive CHKB mutations cause a rare form of congenital muscular dystrophy known as megaconial congenital muscular dystrophy (MCMD). Case presentation We describe a novel proband presenting MCMD due to unpublished CHKB mutations. The patient is a 6-year-old boy who came to our attention for cognitive impairment and slowly progressive muscular weakness. He was the first son of non-consanguineous healthy parents from Sri Lanka. Neurological examination showed proximal weakness at four limbs, weak osteotendinous reflexes, Gowers’ maneuver, and waddling gate. Creatine kinase levels were mildly increased. EMG and brain MRI were normal. Left quadriceps skeletal muscle biopsy showed a myopathic pattern with nuclear centralizations and connective tissue increase. Histological and histochemical staining suggested subsarcolemmal localization and dimensional increase of mitochondria. Ultrastructural analysis confirmed the presence of enlarged (“megaconial”) mitochondria. Direct sequencing of CHKB identified two novel defects: the c.1060G > C (p.Gly354Arg) substitution and the c.448-56_29del intronic deletion, segregating from father and mother, respectively. Subcloning of RT-PCR amplicons from patient’s muscle RNA showed that c.448-56_29del results in the partial retention (14 nucleotides) of intron 3, altering physiological splicing and transcript stability. Biochemical studies showed reduced levels of the mitochondrial fission factor DRP1 and the severe impairment of mitochondrial respiratory chain activity in patient’s muscle compared to controls. Conclusions This report expands the molecular findings associated with MCMD and confirms the importance of considering CHKB variants in the differential diagnosis of patients presenting with muscular dystrophy and mental retardation. The clinical outcome of MCMD patients seems to be influenced by CHKB molecular defects. Histological and ultrastructural examination of muscle biopsy directed molecular studies and allowed the identification and characterization of an intronic mutation, usually escaping standard molecular testing.
Supplementary Information The online version contains supplementary material available at 10.1186/s13395-022-00306-8.
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Affiliation(s)
- Francesca Magri
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Sara Antognozzi
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Michela Ripolone
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Simona Zanotti
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Laura Napoli
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Patrizia Ciscato
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Daniele Velardo
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Giulietta Scuvera
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Medical Genetics Unit, Woman-Child-Newborn Department, Milan, Italy
| | - Valeria Nicotra
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Medical Genetics Unit, Woman-Child-Newborn Department, Milan, Italy
| | - Antonella Giacobbe
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neonatal Intensive Care Unit, Milan, Italy
| | - Donatella Milani
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neonatal Intensive Care Unit, Milan, Italy
| | - Francesco Fortunato
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Manuela Garbellini
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Monica Sciacco
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Stefania Corti
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy.,Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Giacomo Pietro Comi
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy.,IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
| | - Dario Ronchi
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy. .,Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
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8
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González-Jamett A, Vásquez W, Cifuentes-Riveros G, Martínez-Pando R, Sáez JC, Cárdenas AM. Oxidative Stress, Inflammation and Connexin Hemichannels in Muscular Dystrophies. Biomedicines 2022; 10:biomedicines10020507. [PMID: 35203715 PMCID: PMC8962419 DOI: 10.3390/biomedicines10020507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 12/16/2022] Open
Abstract
Muscular dystrophies (MDs) are a heterogeneous group of congenital neuromuscular disorders whose clinical signs include myalgia, skeletal muscle weakness, hypotonia, and atrophy that leads to progressive muscle disability and loss of ambulation. MDs can also affect cardiac and respiratory muscles, impairing life-expectancy. MDs in clude Duchenne muscular dystrophy, Emery-Dreifuss muscular dystrophy, facioscapulohumeral muscular dystrophy and limb-girdle muscular dystrophy. These and other MDs are caused by mutations in genes that encode proteins responsible for the structure and function of skeletal muscles, such as components of the dystrophin-glycoprotein-complex that connect the sarcomeric-actin with the extracellular matrix, allowing contractile force transmission and providing stability during muscle contraction. Consequently, in dystrophic conditions in which such proteins are affected, muscle integrity is disrupted, leading to local inflammatory responses, oxidative stress, Ca2+-dyshomeostasis and muscle degeneration. In this scenario, dysregulation of connexin hemichannels seem to be an early disruptor of the homeostasis that further plays a relevant role in these processes. The interaction between all these elements constitutes a positive feedback loop that contributes to the worsening of the diseases. Thus, we discuss here the interplay between inflammation, oxidative stress and connexin hemichannels in the progression of MDs and their potential as therapeutic targets.
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Affiliation(s)
- Arlek González-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (W.V.); (J.C.S.)
- Escuela de Química y Farmacia, Facultad de Farmacia, Universidad de Valparaíso, Valparaíso 2360102, Chile; (G.C.-R.); (R.M.-P.)
- Correspondence: (A.G.-J.); (A.M.C.)
| | - Walter Vásquez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (W.V.); (J.C.S.)
| | - Gabriela Cifuentes-Riveros
- Escuela de Química y Farmacia, Facultad de Farmacia, Universidad de Valparaíso, Valparaíso 2360102, Chile; (G.C.-R.); (R.M.-P.)
| | - Rafaela Martínez-Pando
- Escuela de Química y Farmacia, Facultad de Farmacia, Universidad de Valparaíso, Valparaíso 2360102, Chile; (G.C.-R.); (R.M.-P.)
| | - Juan C. Sáez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (W.V.); (J.C.S.)
| | - Ana M. Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (W.V.); (J.C.S.)
- Correspondence: (A.G.-J.); (A.M.C.)
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