The Microbiota‐Gut‐Brain Connection: A New Horizon in Neurological and Neuropsychiatric Disorders

The Microbiota‐Gut‐Brain Connection: A New Horizon in Neurological and Neuropsychiatric Disorders Md. Faysal Department of Pharmacy, Faculty of Health and Life Sciences Daffodil International University Dhaka Bangladesh https://orcid.org/0000-0001-5948-4749 Mehrukh Zehravi Department of Clinical Pharmacy, College of Dentistry & Pharmacy Buraydah Private Colleges Buraydah Saudi Arabia Baishakhi Sutradhar Department of Microbiology Gono University (Bishwabidyalay) Dhaka Bangladesh Md Al Amin Department of Pharmacy, Faculty of Health and Life Sciences Daffodil International University Dhaka Bangladesh Thukani Sathanantham Shanmugarajan Department of Pharmaceutics, School of Pharmaceutical Sciences Vels Institute of Science, Technology and Advanced Studies (VISTAS) Chennai Tamil Nadu India Uppuluri Varuna Naga Venkata Arjun Department of Pharmaceutics, School of Pharmaceutical Sciences Vels Institute of Science, Technology and Advanced Studies (VISTAS) Chennai Tamil Nadu India Susithra Ethiraj College of Pharmacy Sri Venkateswara University Chennai Tamil Nadu India Akiladevi Durairaj Department of Pharmaceutics, School of Pharmaceutical Sciences Vels Institute of Science, Technology and Advanced Studies (VISTAS) Chennai Tamil Nadu India Girija Dayalan Department of Pharmaceutics, School of Pharmaceutical Sciences Vels Institute of Science, Technology and Advanced Studies (VISTAS) Chennai Tamil Nadu India Shaik Khadeer Ahamad Department of Pharmaceutics, School of Pharmaceutical Sciences Vels Institute of Science, Technology and Advanced Studies (VISTAS) Chennai Tamil Nadu India Safia Obaidur Rab Department of Clinical Laboratory Sciences, College of Applied Medical Science King Khalid University Abha Saudi Arabia Kannan Raman Department of Pharmacology St. Johns College of Pharmaceutical Sciences & Research Idukki Kerala India Talha Bin Emran Department of Pharmacy, Faculty of Health and Life Sciences Daffodil International University Dhaka Bangladesh https://orcid.org/0000-0003-3188-2272 ABSTRACT Introduction

The microbiota‐gut‐brain axis (MGBA), a complex two‐way connection between the gut microbiota and the brain, has become a key regulator of neurological and neuropsychiatric disorders. Neurological disorders and gut microbiota dysbiosis are linked to these diseases. Changes in gut microbiota can lead to neurotransmitter imbalances, oxidative stress, and neuroinflammation. Gut dysbiosis may contribute to the development of diseases such as depression, autism, schizophrenia, bipolar disorder, Parkinson's disease, Alzheimer's disease, dementia, multiple sclerosis, epilepsy, anxiety, and autism spectrum disorders through immunological regulation, neuroinflammation, and neurotransmitter metabolism changes.
Method

This review systematically sourced articles related to microbiota gut brain axis, neurological disorders, neuropsychiatric disorders and clinical studies from major medical databases, including Scopus, PubMed, and Web of Science.
Results

This review explores the molecular processes underlying MGBA interactions, including vagus nerve signaling, systemic immunological responses, and metabolites produced by microorganisms. The discussion explores the potential of microbiome‐targeted treatments like fecal microbiota transplantation, probiotics, and prebiotics as effective treatment methods. The comprehension of the MGBA can revolutionize neurology and psychiatry, introducing innovative diagnostic and therapeutic approaches. Multiple elements, including diet, metabolism, age, stress, and medications, shape the human gut microbiota, and intestinal imbalances can lead to CNS diseases. The MGBA interacts with gut bacteria, and gut dysbiosis is associated with neurological disorders.
Conclusions

The review demonstrates the correlation between gut microbiota and neurologically associated diseases, highlighting its importance in neurogenesis, mental development, emotions, and behaviors. MGBA, mediated by microbial metabolites, affects brain function and neuroinflammation. Interventions like fetal microbiota transplantation, probiotics, and prebiotics can improve microbial balance, but more clinical research is needed.
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