Neuro-SysMed Seminar December 10, 2025

Speaker: Professor Charalampos Tzoulis, Professor of Neurology and Neurogenetics at the University of Bergen and Haukeland University Hospital in Bergen, Norway. He serves as Director of the Neuro-SysMed Center of Excellence for Clinical Neurological Research, where he leads the clinical neurodegeneration program. He is also Head of the DECODE-PD Research Group, and Director of the KG Jebsen Center for Translational Research in Parkinson’s Disease. 

Topic: "Is there a mitochondrial subtype of Parkinson’s disease?"

Registration through this link. Deadline if you'd like to join the lunch is Dec. 8 at 11.00 

Place: The auditorium in Armauer Hansens Hus

When: December 10, 2025, at 11:30 - 13:00 (lunch 11:30 - 12:00).

Abstract: Mitochondrial dysfunction - particularly respiratory complex deficiencies and mitochondrial DNA (mtDNA) abnormalities - has long been implicated in Parkinson’s disease (PD). Yet the precise causes, mechanisms, and downstream effects of altered mitochondrial function in PD remain unresolved.

In this talk, I will present evidence indicating that mitochondrial dysfunction is not a universal hallmark of PD but instead characterizes a distinct biological subtype. Approximately 20% of individuals with idiopathic PD show widespread neuronal complex I (CI) deficiency, increased mtDNA deletions, a unique transcriptional profile, and a non-tremor–dominant phenotype. In contrast, the majority of patients show no extra-nigral mitochondrial impairment. Muscle biopsy data support this pattern, with CI deficiency seen in 10–15% of cases. I will also share new, unpublished findings from our group indicating that neuronal CI deficiency may arise through at least two mechanistically different routes: an mtDNA-dependent pathway and an mtDNA-independent pathway, suggesting molecular heterogeneity at the cellular level.

Together, these data support the existence of a mitochondrial endotype of idiopathic PD, with significant mechanistic and therapeutic implications.

About the speaker: Charalampos Tzoulis is Professor of Neurology and Neurogenetics at the University of Bergen and Haukeland University Hospital in Bergen, Norway. He serves as Director of the Neuro-SysMed Center of Excellence for Clinical Neurological Research, where he leads the clinical neurodegeneration program. He is also Head of the DECODE-PD Research Group (external link), and Director of the KG Jebsen Center for Translational Research in Parkinson’s Disease. 

An internationally recognized expert in movement disorders and neurodegeneration, Prof. Tzoulis has made significant scientific contributions, particularly in understanding the role of mitochondrial dysfunction and NAD metabolism in Parkinson’s disease (PD) and related α-synucleinopathies. He is currently leading a comprehensive research portfolio including Phase 1-3 trials, as well as platform-based trials such as SLEIPNIR and HYDRA, national multi-arm multi-stage (MAMS) infrastructures for testing neuroprotective, disease-modifying interventions in PD. Prof. Tzoulis has extensive experience in end-to-end trial leadership, spanning protocol design, regulatory submissions, biomarker integration (CSF, imaging, omics, digital endpoints), and academic-industry partnerships. His group has successfully initiated and coordinated nationally and internationally sponsored investigator-initiated trials and multicenter collaborations across Europe and the US, partnering with pharmaceutical and biotech companies, as well as patient organizations.