The Role of Gut Bacteria in Affecting Brain Health and Its Relationship with Neurological Diseases

Authors

  • Moamen Abdelfadil Ismail
  • Saad Almutairi
  • Ali Fayez Ali Alasmari
  • Loloh Mohammed Alkanderi
  • Shahad Ali M Alshehri
  • Rawan Abdulaziz Alharbi
  • Amnah Ahmed Dashti
  • Hana OBAID Alshammari
  • Rana Anas Beser
  • Hosam Eldin Mostafa

DOI:

https://doi.org/10.69980/ajpr.v28i5.453

Abstract

Background: The gut-brain axis represents a bidirectional communication network between the gastrointestinal system and the central nervous system, with gut microbiota playing a pivotal role in influencing brain health. Emerging evidence links gut dysbiosis to neurological disorders such as Parkinson’s disease, Alzheimer’s disease, and major depressive disorder. This study aimed to investigate the relationship between gut microbiota composition and neurological health by comparing individuals with neurological diseases to healthy controls.

Methods: A quantitative, observational, case-control design was employed, involving 200 participants (100 with neurological disorders and 100 healthy controls). Fecal samples were collected, and microbial DNA was sequenced using the Illumina MiSeq platform targeting the V3-V4 regions of the 16S rRNA gene. Microbial diversity and composition were analyzed using bioinformatics tools (QIIME2, SILVA database). Sociodemographic, lifestyle, and clinical data were collected via questionnaires and medical records. Statistical analyses included t-tests, chi-square tests, and multivariable regression.

Results: The neurological group showed significantly lower levels of beneficial bacteria (Bacteroides: 41% vs. 78%; Lactobacillus: 38% vs. 66%) and higher levels of potentially harmful genera (Clostridium: 71% vs. 40%; Escherichia: 64% vs. 33%) compared to controls. Neuropsychiatric symptoms were prevalent, with 35% exhibiting severe cognitive impairment and 44% severe mood disturbances. Lifestyle factors like sedentary behavior (62% vs. 36%) and high sugar intake (66% vs. 40%) were more common in the neurological group.

Conclusion: The study confirms a distinct gut microbiota profile in individuals with neurological diseases, supporting the role of gut dysbiosis in neurological dysfunction. These findings highlight the potential for microbiota-targeted interventions (e.g., probiotics, dietary modifications) as therapeutic strategies. Further research is needed to establish causal mechanisms and develop personalized approaches for improving brain health through gut microbiota modulation.

Author Biographies

Moamen Abdelfadil Ismail

Lecturer Of Internal Medicine, Faculty of Medicine, Helwan University, Internal Medicine Consultant, King Abdulaziz Specialist Hospital - Sakaka – Aljouf

Saad Almutairi

Neurology Resident (R0), Currently Assistant Registrar in Internal Medicine

Ali Fayez Ali Alasmari

Medical Intern - King Khalid University

Loloh Mohammed Alkanderi

5th Year Medical Student

Shahad Ali M Alshehri

Medical Intern, King Khalid University, ABHA

Rawan Abdulaziz Alharbi

Medical Student

Amnah Ahmed Dashti

Internship

Hana OBAID Alshammari

Medical Student

Rana Anas Beser

Medical Service

Hosam Eldin Mostafa

Lecturer Of Neurosurgery, Cairo University

References

1. Colella, M., Charitos, I. A., Ballini, A., Cafiero, C., Topi, S., Palmirotta, R., & Santacroce, L. (2023). Microbiota revolution: How gut microbes regulate our lives. World journal of gastroenterology, 29(28), 4368–4383. https://doi.org/10.3748/wjg.v29.i28.4368

2. Ashique, S., Mohanto, S., Ahmed, M. G., Mishra, N., Garg, A., Chellappan, D. K., Omara, T., Iqbal, S., & Kahwa, I. (2024). Gut-brain axis: A cutting-edge approach to target neurological disorders and potential synbiotic application. Heliyon, 10(13), e34092. https://doi.org/10.1016/j.heliyon.2024.e34092

3. Chandrasekaran, P., Weiskirchen, S., & Weiskirchen, R. (2024). Effects of Probiotics on Gut Microbiota: An Overview. International journal of molecular sciences, 25(11), 6022. https://doi.org/10.3390/ijms25116022

4. Chen, Y., Xu, J., & Chen, Y. (2021). Regulation of Neurotransmitters by the Gut Microbiota and Effects on Cognition in Neurological Disorders. Nutrients, 13(6), 2099. https://doi.org/10.3390/nu13062099

5. Kandpal, M., Indari, O., Baral, B., Jakhmola, S., Tiwari, D., Bhandari, V., Pandey, R. K., Bala, K., Sonawane, A., & Jha, H. C. (2022). Dysbiosis of Gut Microbiota from the Perspective of the Gut-Brain Axis: Role in the Provocation of Neurological Disorders. Metabolites, 12(11), 1064. https://doi.org/10.3390/metabo12111064

6. Luczynski, P., McVey Neufeld, K. A., Oriach, C. S., Clarke, G., Dinan, T. G., & Cryan, J. F. (2016). Growing up in a Bubble: Using Germ-Free Animals to Assess the Influence of the Gut Microbiota on Brain and Behavior. The international journal of neuropsychopharmacology, 19(8), pyw020. https://doi.org/10.1093/ijnp/pyw020

7. Zhang, X., Tang, B., & Guo, J. (2023). Parkinson's disease and gut microbiota: from clinical to mechanistic and therapeutic studies. Translational neurodegeneration, 12(1), 59. https://doi.org/10.1186/s40035-023-00392-8

8. Zhou, P., Chen, C., Patil, S., & Dong, S. (2024). Unveiling the therapeutic symphony of probiotics, prebiotics, and postbiotics in gut-immune harmony. Frontiers in nutrition, 11, 1355542. https://doi.org/10.3389/fnut.2024.1355542

9. Puig-Castellví, F., Pacheco-Tapia, R., Deslande, M., Jia, M., Andrikopoulos, P., Chechi, K., Bonnefond, A., Froguel, P., & Dumas, M. (2023). Advances in the integration of metabolomics and metagenomics for human gut microbiome and their clinical applications. TrAC Trends in Analytical Chemistry, 167, 117248. https://doi.org/10.1016/j.trac.2023.117248

10. Fekete, M., Lehoczki, A., Major, D., Fazekas-Pongor, V., Csípő, T., Tarantini, S., Csizmadia, Z., & Varga, J. T. (2024). Exploring the Influence of Gut-Brain Axis Modulation on Cognitive Health: A Comprehensive Review of Prebiotics, Probiotics, and Symbiotics. Nutrients, 16(6), 789. https://doi.org/10.3390/nu16060789

11. Suganya, K., & Koo, B. S. (2020). Gut-Brain Axis: Role of Gut Microbiota on Neurological Disorders and How Probiotics/Prebiotics Beneficially Modulate Microbial and Immune Pathways to Improve Brain Functions. International journal of molecular sciences, 21(20), 7551. https://doi.org/10.3390/ijms21207551

12. Tiwari, P., Dwivedi, R., Bansal, M., Tripathi, M., & Dada, R. (2023). Role of Gut Microbiota in Neurological Disorders and Its Therapeutic Significance. Journal of clinical medicine, 12(4), 1650. https://doi.org/10.3390/jcm12041650

13. Ullah, H., Arbab, S., Tian, Y., Liu, C. Q., Chen, Y., Qijie, L., Khan, M. I. U., Hassan, I. U., & Li, K. (2023). The gut microbiota-brain axis in neurological disorder. Frontiers in neuroscience, 17, 1225875. https://doi.org/10.3389/fnins.2023.1225875

14. Dash, S., Syed, Y. A., & Khan, M. R. (2022). Understanding the Role of the Gut Microbiome in Brain Development and Its Association With Neurodevelopmental Psychiatric Disorders. Frontiers in cell and developmental biology, 10, 880544. https://doi.org/10.3389/fcell.2022.880544

15. Cryan, J. F., O'Riordan, K. J., Sandhu, K., Peterson, V., & Dinan, T. G. (2020). The gut microbiome in neurological disorders. The Lancet. Neurology, 19(2), 179–194. https://doi.org/10.1016/S1474-4422(19)30356-4

16. Chaudhry, T. S., Senapati, S. G., Gadam, S., Mannam, H. P. S. S., Voruganti, H. V., Abbasi, Z., Abhinav, T., Challa, A. B., Pallipamu, N., Bheemisetty, N., & Arunachalam, S. P. (2023). The Impact of Microbiota on the Gut-Brain Axis: Examining the Complex Interplay and Implications. Journal of clinical medicine, 12(16), 5231. https://doi.org/10.3390/jcm12165231

17. He, Y., Wang, K., Su, N., Yuan, C., Zhang, N., Hu, X., Fu, Y., & Zhao, F. (2024). Microbiota-gut-brain axis in health and neurological disease: Interactions between gut microbiota and the nervous system. Journal of cellular and molecular medicine, 28(18), e70099. https://doi.org/10.1111/jcmm.70099

18. Suganya, K., & Koo, B. S. (2020). Gut-Brain Axis: Role of Gut Microbiota on Neurological Disorders and How Probiotics/Prebiotics Beneficially Modulate Microbial and Immune Pathways to Improve Brain Functions. International journal of molecular sciences, 21(20), 7551. https://doi.org/10.3390/ijms21207551

19. Kim, G. H., & Shim, J. O. (2023). Gut microbiota affects brain development and behavior. Clinical and experimental pediatrics, 66(7), 274–280. https://doi.org/10.3345/cep.2021.01550

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Published

2025-06-16