About Gut-Brain Axis

2015

1. Critically explores the current evidences in identifying a role for the gut microbiota in modulating the brain and the gut/brain axis in humans.

Mayer EA, Tillisch K, Gupta A. Gut/brain axis and the microbiota. J Clin Invest 2015;125(3):926-938.

2. Discusses the intestinal microbiota as being potentially important to development of many childhood diseases such as autism spectrum disorders, allergic disease, and obesity. The authors highlight the impact factors on microbiota colonization in early-life and the developing systems that may be involved in the manifestation of childhood diseases.

O’ Mahony SM, Stilling RM, Dinan TG, Cryan JF. The microbiome and childhood diseases: focus on brain-gut axis. Birth Defects Res C Embryo Today 2015;105(4):296-313.

3. Demonstrates that microbiota can regulate the maturation and function of the neuronal cell microglia by showing in experiments with mice that changes in host microbiota was associated with variations in microglia properties.

Erny D, Hrabě de Angelis AL, Jaitin D et al. Host microbiota constantly control maturation and function of microglia in the CNS. Nat Neurosci 2015;18(7):965-977.

2016

1. Evaluates serotonin as a major player in regulating enteric neuronal development, and that deficient serotonin signaling during development may contribute to gastrointestinal disturbances and behavioral features of Autism Spectrum Disorder.

Margolis KG, Li Z, Stevanovic K, Saurman V et al. Serotonin transporter variant drives preventable gastrointestinal abnormalities in development and function. J Clin Invest 2016;126(6):2221-2235.

2. Provides a state-of-the art description of the mechanisms by which gut microbiota can affect the gut-brain axis and the multiple cellular and molecular communication circuits, including the neuroactive molecules catecholamines, histamine, and serotonin, with special focus on gamma-aminobutyric acid (GABA) signaling.

Mazzoli R, Pessione E. The neuro-endocrinological role of microbial glutamate and GABA signaling. Front Microbiol 2016;7:1934.

3. Assesses the role of gut microbiome in shaping brain development and neurological function, and the mechanisms by which it can contribute to mental illness. It also discusses the influence of gut microbiome on neural development, cognition and depressive-like behavior.

Rogers GB, Keating DJ, Young RL, Wong ML, Licinio J, Wesselingh S. From gut dysbiosis to altered brain function and mental illness: mechanisms and pathways. Mol Psychiatry 2016;21(6):738-748.

2017

1. Discusses the dysbiosis and inflammation of the gut linked to gut microbiota and associated with the development of mental illnesses such as anxiety and depression, and possible applications of probiotics to reduce symptoms.

Clapp M, Aurora N, Herrera L, Bhatia M, Wilen E, Wakefield S. Gut microbiota’s effect on mental health: the gut-brain axis. Clin Pract 2017;7(4):987.

2. Assesses the role of intestinal microbes in modulating the maturation and function of immune cells in the central nervous system and influence the activation of peripheral immune cells, which regulate responses to neuroinflammation, brain injury, autoimmunity and neurogenesis. The immune system as an emerging and important regulator of the microbiota-gut-brain axis during health and neurological diseases.

Fung TC, Olson CA, Hsiao EY. Interactions between the microbiota, immune and nervous systems in health and disease. Nat Neurosci 2017;20(2):145-155.

3. Reviews the effects of the microbiome on immunological system and the influence of the microbiota-derived bioactive molecules in the promotion of inflammation within the intestine and distally at sites as anatomically remote as the brain.

Blander JM, Longman RS, Iliev ID, Sonnenberg GF, Artis D. Regulation of inflammation by microbiota interactions with the host. Nat Immunol 2017;18(8):851-860.

2018

1. Reviews the bidirectional interactions between gut microbes and the central nervous system that can collaborate to development of many psychiatric and neurological disorders.

Martin CR, Osadchiy V, Kalani A, Mayer EA. The brain-gut-microbiome axis. Cell Mol Gastroenterol Hepatol 2018;6(2):133-148.

2. Provides a comprehensive overview of the role played by gut microbiota and the enteric nervous system in development of many neurological diseases, such as Parkinson’s and Alzheimer diseases, amyotrophic lateral sclerosis and multiple sclerosis.

Pellegrini C, Antonioli L, Colucci R, Blandizzi C, Fornai M. Interplay among gut microbiota, intestinal mucosal barrier and enteric neuro-immune system: a common path to neurodegenerative diseases? Acta Neuropathol 2018 May 24. PMID: 29797112

3. Postulates that development of Alzheimer’s disease may be closely related to the imbalance of gut microbiota by detailing that increased leaky gut and the consequent invasion of different bacteria and viruses can lead to neuroinflammatory reactions in the brain.

Sochocka M, Donskow-Łysoniewska K, Diniz BS, Kurpas D, Brzozowska E, Leszek J. The gut microbiome alterations and inflammation-driven pathogenesis of Alzheimer’s disease-a critical review. Mol Neurobiol 2018 Jun 23. PMID:29936690

4. Discusses that increased intestinal permeability can directly affect the central nervous system and be associated with the development of multiple sclerosis (MS), and that disease-modifying drugs in MS could alter the intestinal barrier and the microbiome.

Camara-Lemarroy CR, Metz L, Meddings JB, Sharkey KA, Wee Yong V. The intestinal barrier in multiple sclerosis: implications for pathophysiology and therapeutics. Brain 2018;141(7):1900-1916.

5. Examines the evidences that the intestinal microbiome can mediate behavioral changes in patients with cancer who are receiving chemotherapy, and that modification of the microbiome during cancer treatment can ameliorate the associated behavioral changes.

Jordan KR, Loman BR, Bailey MT, Pyter LM. Gut microbiota-immune-brain interactions in chemotherapy-associated behavioral comorbidities. Cancer 2018 Jul 5. PMID: 29975400

6. Reviews the available clinical data and animal experimental models pointing to the neurotransmitter serotonin as a major player in the development of autism spectrum disorder (ASD) as high levels of the serotonin system have been identified in ASD.

Muller CL, Anacker AMJ, Veenstra-VanderWeele J. The serotonin system in autism spectrum disorder: from biomarker to animal models. Neuroscience 2016;321:24-41.

About brain health

2018

 

Addresses the microbiome’s multiple interactions with the central nervous system (CNS) and the blood-brain barrier—and the related effects on brain function.

Logsdon AF, Erickson MA, Rhea EM et al. Gut reactions: how the blood-brain barrier connects the microbiome and the brain. Experimental Biology and Medicine (Maywood, N.J.) 2018;243(2): 159-165.

 

Suggests that low-grade gut inflammation may be the trigger responsible for over-activating parts of the brain in Parkinson’s disease (PD) and may provide clues to biomarkers that can identify early PD.

Nair AT, Ramachandran V, Joghee NM et al. Gut microbiota dysfunction as reliable non-invasive early diagnostic biomarkers in the pathophysiology of Parkinson’s disease: a critical review. Journal of Neurogastroenterology and Motility 2018;24(1): 30-42.

 

2017

 

Discusses the gut microbiome’s influence on formation of the brain’s serotonergic system—the neurotransmitter system that, when disturbed, plays a key role in the development of neurological diseases such as multiple sclerosis.

Malinova TS, Dijkstra CD, de Vries HE. Serotonin: a mediator of the gut-brain axis in multiple sclerosis. Multiple Sclerosis 2017 Nov 1: 1352458517739975.

 

Explores the gut microbiota’s involvement in diverse neural functions, including myelination, microglial function, neuronal morphology, and blood-brain barrier integrity.

Wiley NC, Dinan TG, Ross RP et al. The microbiota-gut-brain axis as a key regulator of neural function and the stress response: implications for human and animal health. Journal of Animal Science 2017;95(7): 3225-3246.

 

2016

 

Argues that the therapeutic potential of the microbiota-gut-brain axis requires more “robust” and “reproducible” research to address knowledge gaps about functions and interactions between the gut microbiome; the endocrine, immune, and nervous systems; and the brain.

Forsythe P, Kunze W, Bienenstock J. Moody microbes or fecal phrenology: what do we know about the microbiota-gut-brain axis? BMC Medicine 2016;14: 58.

 

Explores mounting evidence that the gut microbiome plays an important role in directing and facilitating developmental processes in the brain.

Sharon G, Sampson TR, Geschwind DH et al. The central nervous system and the gut microbiome. Cell 2016;167(4): 915-932.

 

2015

 

Describes how disruptions in the health of the gut microbiome contribute to numerous disease processes, as illustrated by the relationship between gut health and brain and behavioral function in autism spectrum disorder.

Frye RE, Slattery J, MacFabe DF et al. Approaches to studying and manipulating the enteric microbiome to improve autism symptoms. Microbial Ecology in Health and Disease 2015; 26(1): Article 26878.

 

Discusses a healthy blood-brain barrier’s reliance on constant communication with the gut microbiota, which regulates blood-brain barrier integrity.

Keaney J, Campbell M. The dynamic blood-brain barrier. The FEBS Journal 2015;282(21): 4067-4079.

 

David Perlmutter describes the intricate relationship between the gut microbiome and the brain in his New York Times bestseller, Brain Maker; in this article, Perlmutter and others talk about the “medical revolution” under way in the treatment of brain-related disorders.

Why the digestive system and its bacteria are a ‘second brain,’” RN, Aug. 20, 2015.

 

Reports Danish research on gut health and Parkinson’s disease focusing on the role of the vagus nerve as the pathway to the brain.

Svensson E, Horváth-Puhó E, Thomsen RW et al. Vagotomy and subsequent risk of Parkinson’s disease. Annals of Neurology 2015;78(4): 522-529.

See also, “Parkinson’s may begin in gut and spread to the brain via the vagus nerve,” Neuroscience News, June 23, 2015.