You are currently viewing a new version of our website. To view the old version click .
Biomedicines
  • Editorial
  • Open Access

29 December 2025

Recent Advances in Understanding of the Role of Synuclein Family Members in Health and Disease Volume II

and
1
School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
2
Research Institute of Pharmacology of Living Systems, Belgorod State National Research University, 308015 Belgorod, Russia
*
Author to whom correspondence should be addressed.
This article belongs to the Section Neurobiology and Clinical Neuroscience
The synuclein family of three short, intrinsically disordered and predominantly neurospecific proteins (α-, β-, and γ-synuclein) [1] has attracted the attention of researchers and clinicians due to their direct or indirect involvement in the molecular pathogenesis of certain neurodegenerative diseases, mainly α-synucleinopathies [2,3,4].
Despite significant progress in our understanding of the role of α-synuclein in the aetiology and pathogenesis of these diseases [5,6], many aspects of this protein disfunction, as well as its normal function in the nervous system and beyond, are still enigmatic [7,8,9,10]. The role of two other members of the synuclein family in these processes is even less clear [11,12,13]. This makes the identification of targets and tools for the efficient combating of pathological processes in the nervous systems of patients with α-synucleinopathies rather difficult.
Therefore, further and more detailed studies on the normal function and malfunction of each member of the synuclein family, employing a variety of different methodological approaches, are timely and important. This Special Issue is devoted to some of such studies.
The interactions of synucleins with other proteins [14,15,16], lipid membranes [17,18,19,20], and various small molecules [21,22] as modifiers of synucleins’ ability and/or propensity to aggregate and, consequently, produce various molecular species toxic to neurons [23,24] has been a focus of many studies because such interactions represent a promising target for the disease-modifying therapy of α-synucleinopaties.
For a number of years, an accumulation of iron was considered a potential trigger of pathological processes, leading to the development and progression of the most common α-synucleinopaty, Parkinson’s disease; therefore, iron chelators could be used in the treatment of this disease [25,26,27]. However, the paper by Huenchuguala and Segura-Aguilar, published in this issue [28], provides recent evidence that this is not the case, and that iron is not an important player in the development of neurodegeneration in Parkinson’s disease.
A growing body of evidence points to the gut–brain axis as one of the main routes of α-synuclein pathology spreading across the body, with the gut endothelial cells being a primary source of pathological species of α-synuclein aggregation [29,30,31,32]. In their paper, Gorecki et al. [33] demonstrated that the presence of α-synuclein in the enteroendocrine cells and their ability to efficiently internalise its preformed filaments (PFFs) made them an early focal point of the pathology spreading and therefore an attractive target for halting this process at the very early stage. Furthermore, the authors show that the poly-Arginine Peptide R18D is able to prevent PPF uptake. making it a promising therapeutic tool.
In contrast, Surguchov et al. [34] discuss the beneficial rather than the harmful properties of amyloidogenic proteins, including synucleins. The main theme of this paper is the potential link between these proteins and infectious diseases, with a particular emphasis on the COVID-19 pandemic.
In a group of papers, Vorobyev and colleagues used electroencephalogram (EEG) studies to address questions related to the role of the synuclein family members in the functional connectivity between brain regions and the dysfunction of this connectivity typical in neurodegenerative conditions. First, they demonstrated that age-related adaptive changes could alleviate problems in EEG coherence, which reflects the functional connectivity between various brain regions, associated with neurodegenerative conditions [35]. Animal models and particularly mouse models were widely used for studying the involvement of synuclens in normal and pathogenic molecular mechanisms, allowing for the uncovering of new, important details [36,37]. Thus, Vorobyev and colleagues assessed EEG coherence in two knockout mouse lines designed to apply different strategies for α-synuclein depletion. The authors found that suppression of EEG coherence was similar in mice with complete germline knockout of the Snca gene and those following the inactivation of this gene in adult mice by tamoxifen-induced Cre/LoxP recombination [38]. This research group also studied the suppression of EEG coherence in mice with various combinations of germline knockouts of genes encoding members of the synuclein family, including triple knockout mice lacking all three family members [39]. Their results revealed that depending on what synuclein or combination of synucleins is lost, different functional interactions become suppressed in the mouse brain, suggesting specific roles for each synuclein in the synaptic connectivity between various brain regions.

Author Contributions

All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Ministry of Science and Higher Education of the Russian Federation (agreement No. 075-15-2025-558).

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Lavedan, C. The synuclein family. Genome Res. 1998, 8, 871–880. [Google Scholar] [CrossRef]
  2. Goedert, M. Alpha-synuclein and neurodegenerative diseases. Nat. Rev. Neurosci. 2001, 2, 492–501. [Google Scholar] [CrossRef] [PubMed]
  3. Goedert, M.; Jakes, R.; Spillantini, M.G. The Synucleinopathies: Twenty Years On. J. Park. Dis. 2017, 7, S53–S71. [Google Scholar] [CrossRef] [PubMed]
  4. Henderson, M.X.; Trojanowski, J.Q.; Lee, V.M. alpha-Synuclein pathology in Parkinson’s disease and related alpha-synucleinopathies. Neurosci. Lett. 2019, 709, 134316. [Google Scholar] [CrossRef] [PubMed]
  5. Bougea, A. Synuclein in neurodegeneration. Adv. Clin. Chem. 2021, 103, 97–134. [Google Scholar]
  6. Kuo, G.; Kumbhar, R.; Blair, W.; Dawson, V.L.; Dawson, T.M.; Mao, X. Emerging targets of alpha-synuclein spreading in alpha-synucleinopathies: A review of mechanistic pathways and interventions. Mol. Neurodegener. 2025, 20, 10. [Google Scholar] [CrossRef]
  7. Norris, E.H.; Giasson, B.I.; Lee, V.M. Alpha-synuclein: Normal function and role in neurodegenerative diseases. Curr. Top. Dev. Biol. 2004, 60, 17–54. [Google Scholar]
  8. Benskey, M.J.; Perez, R.G.; Manfredsson, F.P. The contribution of alpha synuclein to neuronal survival and function-Implications for Parkinson’s disease. J. Neurochem. 2016, 137, 31–59. [Google Scholar] [CrossRef]
  9. Dolin, H.H.; Zhou, B.; Maitta, R.W. Alpha-Synuclein Dysregulation in Systemic Pathophysiology of Synucleinopathies. Front. Biosci. 2025, 30, 27178. [Google Scholar] [CrossRef]
  10. Zanotti, L.C.; Malizia, F.; Cesatti Laluce, N.; Avila, A.; Mamberto, M.; Anselmino, L.E.; Menacho-Marquez, M. Synuclein Proteins in Cancer Development and Progression. Biomolecules 2023, 13, 980. [Google Scholar] [CrossRef]
  11. Barba, L.; Paolini Paoletti, F.; Bellomo, G.; Gaetani, L.; Halbgebauer, S.; Oeckl, P.; Otto, M.; Parnetti, L. Alpha and Beta Synucleins: From Pathophysiology to Clinical Application as Biomarkers. Mov. Disord. 2022, 37, 669–683. [Google Scholar] [CrossRef] [PubMed]
  12. Surguchov, A.; Surguchev, A. Synucleins: New Data on Misfolding, Aggregation and Role in Diseases. Biomedicines 2022, 10, 3241. [Google Scholar] [CrossRef] [PubMed]
  13. Zahra, F.T.; Kayani, H.; Noreen, S.; Noor, A.; Zafar, S. Synuclein Proteoforms: Role in Health and Disease. Mol. Neurobiol. 2025, 63, 87. [Google Scholar] [CrossRef] [PubMed]
  14. Dev, K.K.; Hofele, K.; Barbieri, S.; Buchman, V.L.; van der Putten, H. Part II: Alpha-synuclein and its molecular pathophysiological role in neurodegenerative disease. Neuropharmacology 2003, 45, 14–44. [Google Scholar] [CrossRef]
  15. Hernandez, S.M.; Tikhonova, E.B.; Karamyshev, A.L. Protein-Protein Interactions in Alpha-Synuclein Biogenesis: New Potential Targets in Parkinson’s Disease. Front. Aging Neurosci. 2020, 12, 72. [Google Scholar] [CrossRef]
  16. Wang, J.; Dai, L.; Chen, S.; Zhang, Z.; Fang, X.; Zhang, Z. Protein-protein interactions regulating alpha-synuclein pathology. Trends Neurosci. 2024, 47, 209–226. [Google Scholar] [CrossRef]
  17. Pfefferkorn, C.M.; Jiang, Z.; Lee, J.C. Biophysics of alpha-synuclein membrane interactions. Biochim. Biophys. Acta 2012, 1818, 162–171. [Google Scholar] [CrossRef]
  18. Snead, D.; Eliezer, D. Alpha-synuclein function and dysfunction on cellular membranes. Exp. Neurobiol. 2014, 23, 292–313. [Google Scholar] [CrossRef]
  19. Kiechle, M.; Grozdanov, V.; Danzer, K.M. The Role of Lipids in the Initiation of alpha-Synuclein Misfolding. Front. Cell Dev. Biol. 2020, 8, 562241. [Google Scholar] [CrossRef]
  20. Bartels, T.; Ahlstrom, L.S.; Leftin, A.; Kamp, F.; Haass, C.; Brown, M.F.; Beyer, K. The N-terminus of the intrinsically disordered protein alpha-synuclein triggers membrane binding and helix folding. Biophys. J. 2010, 99, 2116–2124. [Google Scholar] [CrossRef]
  21. Ahanger, I.A.; Dar, T.A. Small molecule modulators of alpha-synuclein aggregation and toxicity: Pioneering an emerging arsenal against Parkinson’s disease. Ageing Res. Rev. 2024, 101, 102538. [Google Scholar] [CrossRef] [PubMed]
  22. Uversky, V.N.; Li, J.; Fink, A.L. Metal-triggered structural transformations, aggregation, and fibrillation of human alpha-synuclein. A possible molecular NK between Parkinson’s disease and heavy metal exposure. J. Biol. Chem. 2001, 276, 44284–44296. [Google Scholar] [CrossRef] [PubMed]
  23. Li, B.; Ge, P.; Murray, K.A.; Sheth, P.; Zhang, M.; Nair, G.; Sawaya, M.R.; Shin, W.S.; Boyer, D.R.; Ye, S.; et al. Cryo-EM of full-length alpha-synuclein reveals fibril polymorphs with a common structural kernel. Nat. Commun. 2018, 9, 3609. [Google Scholar] [CrossRef] [PubMed]
  24. Calabresi, P.; Mechelli, A.; Natale, G.; Volpicelli-Daley, L.; Di Lazzaro, G.; Ghiglieri, V. Alpha-synuclein in Parkinson’s disease and other synucleinopathies: From overt neurodegeneration back to early synaptic dysfunction. Cell Death Dis. 2023, 14, 176. [Google Scholar] [CrossRef]
  25. Youdim, M.B. Iron in the brain: Implications for Parkinson’s and Alzheimer’s diseases. Mt. Sinai J. Med. 1988, 55, 97–101. [Google Scholar]
  26. Zecca, L.; Youdim, M.B.; Riederer, P.; Connor, J.R.; Crichton, R.R. Iron, brain ageing and neurodegenerative disorders. Nat. Rev. Neurosci. 2004, 5, 863–873. [Google Scholar] [CrossRef]
  27. Tu, R.; Han, Z.; Zhang, H.; Jia, X.; Sun, T.; Liu, H.; Li, J.; Tang, M.; Wang, S. From pathogenesis to treatment: The emerging role of ferroptosis in Parkinson’s disease. Front. Immunol. 2025, 16, 1709561. [Google Scholar] [CrossRef]
  28. Huenchuguala, S.; Segura-Aguilar, J. On the Role of Iron in Idiopathic Parkinson’s Disease. Biomedicines 2023, 11, 3094. [Google Scholar] [CrossRef]
  29. Braak, H.; Del Tredici, K.; Rub, U.; de Vos, R.A.; Jansen Steur, E.N.; Braak, E. Staging of brain pathology related to sporadic Parkinson’s disease. Neurobiol. Aging 2003, 24, 197–211. [Google Scholar] [CrossRef]
  30. Klingelhoefer, L.; Reichmann, H. Pathogenesis of Parkinson disease--the gut-brain axis and environmental factors. Nat. Rev. Neurol. 2015, 11, 625–636. [Google Scholar] [CrossRef]
  31. Klann, E.M.; Dissanayake, U.; Gurrala, A.; Farrer, M.; Wagle Shukla, A.; Ramirez-Zamora, A.; Mai, V.; Vedam-Mai, V. The Gut-Brain Axis and Its Relation to Parkinson’s Disease: A Review. Front. Aging Neurosci. 2021, 13, 782082. [Google Scholar] [CrossRef] [PubMed]
  32. Tan, A.H.; Lim, S.Y.; Lang, A.E. The microbiome-gut-brain axis in Parkinson disease-from basic research to the clinic. Nat. Rev. Neurol. 2022, 18, 476–495. [Google Scholar] [CrossRef] [PubMed]
  33. Gorecki, A.M.; Spencer, H.; Meloni, B.P.; Anderton, R.S. The Poly-Arginine Peptide R18D Interferes with the Internalisation of alpha-Synuclein Pre-Formed Fibrils in STC-1 Enteroendocrine Cells. Biomedicines 2023, 11, 2089. [Google Scholar] [CrossRef] [PubMed]
  34. Surguchov, A.; Emamzadeh, F.N.; Titova, M.; Surguchev, A.A. Controversial Properties of Amyloidogenic Proteins and Peptides: New Data in the COVID Era. Biomedicines 2023, 11, 1215. [Google Scholar] [CrossRef]
  35. Vorobyov, V.; Deev, A.; Chaprov, K.; Ustyugov, A.A.; Lysikova, E. Age-Related Modifications of Electroencephalogram Coherence in Mice Models of Alzheimer’s Disease and Amyotrophic Lateral Sclerosis. Biomedicines 2023, 11, 1151. [Google Scholar] [CrossRef]
  36. Visanji, N.P.; Brotchie, J.M.; Kalia, L.V.; Koprich, J.B.; Tandon, A.; Watts, J.C.; Lang, A.E. alpha-Synuclein-Based Animal Models of Parkinson’s Disease: Challenges and Opportunities in a New Era. Trends Neurosci. 2016, 39, 750–762. [Google Scholar] [CrossRef]
  37. Koprich, J.B.; Kalia, L.V.; Brotchie, J.M. Animal models of alpha-synucleinopathy for Parkinson disease drug development. Nat. Rev. Neurosci. 2017, 18, 515–529. [Google Scholar] [CrossRef]
  38. Vorobyov, V.; Deev, A.; Morozova, O.; Oganesyan, Z.; Krayushkina, A.M.; Ivanova, T.A.; Chaprov, K. Early Effects of Alpha-Synuclein Depletion by Pan-Neuronal Inactivation of Encoding Gene on Electroencephalogram Coherence between Different Brain Regions in Mice. Biomedicines 2023, 11, 3282. [Google Scholar] [CrossRef]
  39. Vorobyov, V.; Deev, A.; Chaprov, K.; Ninkina, N. Disruption of Electroencephalogram Coherence between Cortex/Striatum and Midbrain Dopaminergic Regions in the Knock-Out Mice with Combined Loss of Alpha, Beta, and Gamma Synucleins. Biomedicines 2024, 12, 881. [Google Scholar] [CrossRef]
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Article Metrics

Citations

Article Access Statistics

Multiple requests from the same IP address are counted as one view.