The role of microbiota dysbiosis in Parkinson’s disease: Pathophysiology and therapeutic opportunities

Abstract

Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder characterized by debilitating motor and non-motor symptoms. Its etiology is multifactorial, with no single definitive cause identified, although aging is a significant risk factor. Additional risks include genetic predisposition, family history, and environmental factors such as pesticide exposure and Helicobacter pylori infection. Dysbiosis of the gut microbiota, and in particular bacterial imbalances, has been implicated in the disruption of the gut-brain axis, contributing to both systemic and neuroinflammation. Environmental factors such as antibiotic exposure and toxins can precipitate microbial dysregulation, potentially accelerating PD progression. Understanding the mechanisms of the gut-brain axis and identifying strategies to preserve a healthy microbiome are essential for developing novel therapeutic approaches. This review synthesizes current therapeutic strategies and ongoing research focused on restoring gut-brain balance to combat PD. These approaches include fecal microbiota transplantation, dietary interventions, and probiotic therapies, all of which show promise in mitigating both motor and non-motor symptoms. Furthermore, we emphasize the urgent need for continued research into probiotics and innovative therapeutic approaches for gut-brain axis modulation, presenting novel opportunities for effective PD management.

Keywords

Gut-brain axis / Microbiota dysbiosis / Parkinson’s disease / Probiotic therapy / Neuroinflammation

Declaration of AI in Scientific Writing

During the preparation of this work, the authors used ChatGPT to check grammar and clarity of the text when needed. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.

Declaration of Competing Interest

Authors SS, IS and NA declare no known competing financial interests or personal relationships that could have influenced the work reported in this paper. AC is the scientific founder and advisor of Dragon Biomed, an entrepreneurial initiative at the Universidad San Francisco de Quito (USFQ). He also serves as a scientific advisor in the Research and Development department of Luvigix. In these capacities, AC provides scientific guidance and expertise but does not participate in decision-making or operational activities within either organization.

CRediT authorship contribution statement

Shabnam Santos: Writing - review & editing, Writing - original draft, Investigation, Formal analysis. Ivonne Salinas: Writing - review & editing, Writing - original draft, Investigation, Formal analysis. Nicolás Almeida: Writing - review & editing, Writing - original draft, Investigation, Formal analysis. Andrés Caicedo: Writing - review & editing, Writing - original draft, Visualization, Validation, Supervision, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Conceptualization.

Acknowledgments

This study did not receive specific funding. We extend our gratitude to the School of Medicine, the Instituto de Investigaciones en Biomedicina (USFQ), the Space Front Institute at Universidad San Francisco de Quito, and the Mito-Act Research Consortium in Quito, Ecuador, for their unwavering support of our research and initiatives. The authorship team is grateful to Reema Azar for her assistance in ensuring the appropriate use of the English language in the manuscript.

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