Microbiome–Gut–Brain Axis: Implications for the Links Between Inflammatory Bowel Disease and Neuropsychiatric Disorders

Cheng-Mei Tian,1,2,* Mei-Feng Yang,3,* Chen Kong,1,* Duo Luo,4,* Ning-Ning Yue,1 Hai-Lan Zhao,1 Yuan Zhang,5 Jian-Ping Lu,6 Yu-Jie Liang,6,7 Yang Song,1 Dao-Ru Wei,8 Jun Yao,1 Li-Sheng Wang,1 De-Feng Li1 1Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, 518020, People’s Republic of China; 2Department of Emergency, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; the First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, 518020, People’s Republic of China; 3Department of Hematology, Yantian District People’s Hospital, Shenzhen, Guangdong, 518020, People’s Republic of China; 4Department of Geriatrics, Guangzhou First People’s Hospital, Guangzhou Medical University, Guangzhou, 510180, People’s Republic of China; 5Department of Medical Administration, Huizhou Institute of Occupational Diseases Control and Prevention, Huizhou, Guangdong, 516000, People’s Republic of China; 6Department of Child and Adolescent Psychiatry, Shenzhen Institute of Mental Health, Shenzhen Kangning Hospital, Shenzhen, 518020, People’s Republic of China; 7Jining Medical University, Jining, 272000, People’s Republic of China; 8Department of Rehabilitation, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, 518020, People’s Republic of China*These authors contributed equally to this workCorrespondence: Dao-Ru Wei, Department of Rehabilitation, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), No. 1017, Dongmen North Road, Luohu District, Shenzhen, 518020, People’s Republic of China, Tel +86 755 25533018, Email [email protected] De-Feng Li, Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; the First Affiliated Hospital, Southern University of Science and Technology), No. 1017, Dongmen North Road, Luohu District, Shenzhen, 518020, People’s Republic of China, Tel +86 755 25533018, Email [email protected]: The brain and gastrointestinal tract are closely interconnected as important sensory organs processing signals from both environmental and internal cues. Recent studies have shown that dysregulation of the gut microbiota in inflammatory bowel disease activates the gut immune system. The cross-talk mechanism along the gut-brain axis is implicated in the development of neuropsychiatric disorders such as autism, depression, anxiety, Alzheimer’s disease, and Parkinson’s disease. Here, we discuss the molecular mechanisms involved in signaling across the gut-brain axis, including the immune and neuroendocrine system, intestinal permeability, microbial composition, and bacterial extracellular vesicles. We focus on the link between specific inflammatory bowel disease, microbial genera and psychiatric and neurological disorders, and propose that the results of preclinical and clinical studies open up the possibility of targeting the gut microbiota to treat neuropsychiatric disorders that are altered by gut interactions.Plain Language Summary: There is a strong bidirectional communication between the brain and the digestive system. Dysregulation of the gut microbiota (GM) in inflammatory bowel disease (IBD) activates the gut immune system and contributes to brain disorders. Targeting the gut-brain axis has the potential to treat both neurological disorders such as depression, autism, Alzheimer’s disease, and Parkinson’s syndrome, and to ameliorate intestinal disorders such as IBD. Keywords: Gut–brain axis, GBA, microbiome–gut–brain axis, MGBA, inflammatory bowel disease, IBD, neuropsychiatric disorders, probiotics, psychobiotics