• ADCK3 mutations with epilepsy, stroke-like episodes and ataxia: a POLG mimic? 

      Hikmat, Omar; Tzoulis, Charalampos; Knappskog, Per; Johansson, Stefan; Boman, Helge; Sztromwasser, Pawel Szymon; Lien, Espen; Brodtkorb, Eylert; Ghezzi, Daniele; Bindoff, Laurence (Peer reviewed; Journal article, 2016-07)
      Background and purpose: Defects of coenzyme Q10 (CoQ10) metabolism cause a variety of disorders ranging from isolated myopathy to multisystem involvement. ADCK3 is one of several genes associated with CoQ10 deficiency that ...
    • Clinical and molecular studies of disease caused by mutations of the mitochondrial DNA polymerase gamma (POLG). 

      Tzoulis, Charalampos (Doctoral thesis, 2010-11-26)
      Background: Mutations in the gene encoding the DNA-polymerase gamma (POLG), the enzyme that replicates and repairs the mitochondrial genome, are an important cause of human disease and disability. Over 130 pathogenic ...
    • Defective mitochondrial DNA homeostasis in the substantia nigra in Parkinson disease 

      Dölle, Christian; Flønes, Irene Hana; Sanchez Nido, Gonzalo; Miletic, Hrvoje; Osuagwu, Nelson; Kristoffersen, Stine; Lilleng, Peer Kåre; Larsen, Jan Petter; Tysnes, Ole-Bjørn; Haugarvoll, Kristoffer; Bindoff, Laurence; Tzoulis, Charalampos (Peer reviewed; Journal article, 2016-11-22)
      Increased somatic mitochondrial DNA (mtDNA) mutagenesis causes premature aging in mice, and mtDNA damage accumulates in the human brain with aging and neurodegenerative disorders such as Parkinson disease (PD). Here, we ...
    • Differential transcript usage in the Parkinson’s disease brain 

      Dick, Fiona; Sanchez Nido, Gonzalo; Alves, Guido Werner; Tysnes, Ole-Bjørn; Nilsen, Gry Hilde; Dölle, Christian; Tzoulis, Charalampos (Peer reviewed; Journal article, 2020)
      Studies of differential gene expression have identified several molecular signatures and pathways associated with Parkinson’s disease (PD). The role of isoform switches and differential transcript usage (DTU) remains, ...
    • Disease-specific phenotypes in iPSC-derived neural stem cells with POLG mutations 

      Liang, Xiao; Kristiansen, Cecilie Katrin; Mostafavi, Sepideh; Vatne, Guro H.; Zantingh, Gina; Kianian, Atefeh; Tzoulis, Charalampos; Høyland, Lena Elise; Ziegler, Mathias; Perez, Roberto Megias; Furriol, Jessica; Zhang, Zhuoyuan; Balafkan, Novin; Hong, Yu; Siller, Richard; Sullivan, Gareth; Bindoff, Laurence (Journal article; Peer reviewed, 2020)
      Mutations in POLG disrupt mtDNA replication and cause devastating diseases often with neurological phenotypes. Defining disease mechanisms has been hampered by limited access to human tissues, particularly neurons. Using ...
    • Excellent response of intramedullary Erdheim-Chester disease to vemurafenib: a case report 

      Tzoulis, Charalampos; Schwarzlmüller, Thomas; Søfteland, Eirik; Neckelmann, Gesche; Biermann, Martin; Haroche, Julien; Straume, Oddbjørn; Gjerde, Ivar Otto; Vintermyr, Olav Karsten (Peer reviewed; Journal article, 2015-04-30)
      Background: Erdheim-Chester disease is a rare histiocytosis characterized by multi-systemic organ involvement. Immune-modulating agents such as interferon-alpha have limited success and the disorder is progressive and ...
    • In vitro characterization of six STUB1 variants in spinocerebellar ataxia 16 reveals altered structural properties for the encoded CHIP proteins 

      Pakdaman, Yasaman; Sanchez Guixe, Monica; Kleppe, Rune; Erdal, Sigrid; Bustad, Helene J.; Bjørkhaug, Lise; Haugarvoll, Kristoffer; Tzoulis, Charalampos; Heimdal, Ketil Riddervold; Knappskog, Per; Johansson, Stefan; Aukrust, Ingvild (Peer reviewed; Journal article, 2017)
      Spinocerebellar ataxia, autosomal recessive 16 (SCAR16) is caused by biallelic mutations in the STIP1 homology and U-box containing protein 1 (STUB1) gene encoding the ubiquitin E3 ligase and dimeric co-chaperone C-terminus ...
    • Meta-analysis of whole-exome sequencing data from two independent cohorts finds no evidence for rare variant enrichment in Parkinson disease associated loci 

      Gaare, Johannes Jernqvist; Sanchez Nido, Gonzalo; Dölle, Christian; Sztromwasser, Pawel Szymon; Alves, Guido Werner; Tysnes, Ole-Bjørn; Haugarvoll, Kristoffer; Tzoulis, Charalampos (Journal article; Peer reviewed, 2020-10-01)
      Parkinson disease (PD) is a complex neurodegenerative disorder influenced by both environmental and genetic factors. While genome wide association studies have identified several susceptibility loci, many causal variants ...
    • Mitochondrial DNA depletion in sporadic inclusion body myositis 

      Bhatt, Padmanabh S.; Tzoulis, Charalampos; Balafkan, Novin; Miletic, Hrvoje; Tran, Gia Tuong Thi; Sanaker, Petter Schandl; Bindoff, Laurence (Peer reviewed; Journal article, 2019)
      Sporadic inclusion body myositis (sIBM) is a late onset disorder of unkown aetiology. Mitochondrial changes such as cytochrome oxidase deficient fibres are a well recognised feature and mitochondrial DNA (mtDNA) deletions ...
    • Molecular pathogenesis of polymerase gamma-related neurodegeneration 

      Tzoulis, Charalampos; Tran, Gia Tuong Thi; Coxhead, Jonathan; Bertelsen, Bjørn; Lilleng, Peer Kåre; Balafkan, Novin; Payne, Brendan; Miletic, Hrvoje; Chinnery, Patrick F.; Bindoff, Laurence (Peer reviewed; Journal article, 2014-07)
      Objective: Polymerase gamma (POLG) mutations are a common cause of mitochondrial disease and have also been linked to neurodegeneration and aging. We studied the molecular mechanisms underlying POLG-related neurodegeneration ...
    • MRI characterisation of adult onset alpha-methylacyl-coA racemase deficiency diagnosed by exome sequencing 

      Haugarvoll, Kristoffer; Johansson, Stefan; Tzoulis, Charalampos; Haukanes, Bjørn Ivar; Bredrup, Cecilie; Neckelmann, Gesche; Boman, Helge; Knappskog, Per; Bindoff, Laurence (Peer reviewed; Journal article, 2013-01-03)
      Background: Correct diagnosis is pivotal to understand and treat neurological disease. Herein, we report the diagnostic work-up utilizing exome sequencing and the characterization of clinical features and brain MRI in two ...
    • A multicenter study on Leigh syndrome: disease course and predictors of survival 

      Sofou, Kalliopi; De Coo, Irenaeus F. M.; Isohanni, Pirjo; Ostergaard, Elsebet; Naess, Karin; De Meirleir, Linda; Tzoulis, Charalampos; Uusimaa, Johanna; De Angst, Isabell B.; Lönnqvist, Tuula; Pihko, Helena; Mankinen, Katariina; Bindoff, Laurence; Tulinius, Már; Darin, Niklas (Peer reviewed; Journal article, 2014-04-15)
      Background: Leigh syndrome is a progressive neurodegenerative disorder, associated with primary or secondary dysfunction of the mitochondrial oxidative phosphorylation. Despite the fact that Leigh syndrome is the most ...
    • PNKP Mutations Identified by Whole-Exome Sequencing in a Norwegian Patient with Sporadic Ataxia and Edema 

      Tzoulis, Charalampos; Sztromwasser, Pawel Szymon; Johansson, Stefan; Gjerde, Ivar Otto; Knappskog, Per; Bindoff, Laurence (Journal article, 2017-02)
      We identified PNKP mutations in a Norwegian woman with AOA. This patient had the typical findings with cognitive dysfunction, peripheral neuropathy, cerebellar dysarthria, horizontal nystagmus, oculomotor apraxia, and ...
    • Poly-ADP-ribose assisted protein localization resolves that DJ-1, but not LRRK2 or α-synuclein, is localized to the mitochondrial matrix 

      Osuagwu, Nelson Uchechukwu; Dölle, Christian; Tzoulis, Charalampos (Peer reviewed; Journal article, 2019)
      Several proteins linked to familial Parkinson disease have been associated with mitochondrial (dys-)function and have been described to reside within mitochondria. The putative mitochondrial and sub-mitochondrial localization ...
    • Progressive striatal necrosis associated with anti-NMDA receptor antibodies 

      Tzoulis, Charalampos; Vedeler, Christian A.; Haugen, Mette; Storstein, Anette; Tran, Gia Tuong Thi; Gjerde, Ivar Otto; Biermann, Martin; Schwarzlmüller, Thomas; Bindoff, Laurence (Peer reviewed; Journal article, 2013-05-31)
      Background: We report a case of childhood onset, generalized dystonia due to slowly progressive bilateral striatal necrosis associated with anti-N-methyl-D-aspartate receptor (NMDAR) antibodies. This clinical phenotype has ...
    • Spastic paraplegia type 7 is associated with multiple mitochondrial DNA deletions 

      Wedding, Iselin Marie; Koht, Jeanette; Tran, Gia Tuong Thi; Misceo, Doriana; Selmer, Kaja Kristine; Holmgren, Asbjørn; Frengen, Eirik; Bindoff, Laurence; Tallaksen, Chantal; Tzoulis, Charalampos (Peer reviewed; Journal article, 2014-01-22)
      Spastic paraplegia 7 is an autosomal recessive disorder caused by mutations in the gene encoding paraplegin, a protein located at the inner mitochondrial membrane and involved in the processing of other mitochondrial ...