Front Matter| Volume 48, ISSUE 3, Pvii-ix, September 2019


        Preface xi

        Rochellys Diaz Heijtz

        Prescribed Drugs and the Microbiome 331

        Nele Brusselaers
        The interaction between drug use, the microbiome, and the host is complex and multidimensional. Drugs and the microbiota may be risk factors or protective factors for disease. These interactions may explain interpersonal variations in drug efficacy and toxicity, but also interpersonal variations in microbiota composition and functioning, and potential (long-term) side effects from drugs.

        Gut-Brain Interactions: Implications for a Role of the Gut Microbiota in the Treatment and Prognosis of Anorexia Nervosa and Comparison to Type I Diabetes 343

        Daria Igudesman, Megan Sweeney, Ian M. Carroll, Elizabeth J. Mayer-Davis, and Cynthia M. Bulik
        Anorexia nervosa has poor prognosis and treatment outcomes and is influenced by genetic, metabolic, and psychological factors. Gut microbes interact with gut physiology to influence metabolism and neurobiology, although potential therapeutic benefits remain unknown. Type 1 diabetes is linked to anorexia nervosa through energy dysregulation, which in both disease states is related to the gut microbiota, disordered eating, and genetics.

        The Development of the Human Microbiome: Why Moms Matter 357

        Derrick M. Chu, Gregory C. Valentine, Maxim D. Seferovic, and Kjersti M. Aagaard
        The human body is cohabitated with trillions of commensal bacteria that are essential for our health. However, certain bacteria can also cause diseases in the human host. Before the microbiome can be attributed to disease risk and pathogenesis, normal acquisition and development of the microbiome must be understood. Here, we explore the evidence surrounding in utero microbial exposures and the significant of this exposure in the proper development of the fetal and neonatal microbiome. We further explore the development of the fetal and neonatal microbiome and its relationship to preterm birth, feeding practices, and mode of delivery, and maternal diet.

        The Human Microbiota and Its Relationship with Allergies 377

        Nanna Fyhrquist
        Allergic diseases have been increasing to epidemic proportions during the past century, especially in high-income countries. Recent evidence suggests there might be a link between the allergy epidemic and reduced microbial exposures, resulting from a rapidly evolved modern lifestyle, including changed diets, health and hygiene standards, and daily habits. Recently it has become clear that the microbial communities in our respiratory system and our gut, as well as on our skin, may play a key role in shaping our physiology, and influencing our health. We are only beginning to understand the mechanisms by which the human microbiota may be regulating the immune system, and sudden changes in the composition of the microbiota may have profound effects, linked with an increased risk of developing chronic inflammatory disorders, including allergies.

        Mood and Microbes: Gut to Brain Communication in Depression 389

        John R. Kelly, Veronica O’ Keane, John F. Cryan, Gerard Clarke, and Timothy G. Dinan
        The gut microbiota, acting via the gut-brain axis, modulates key neurobiological systems that are dysregulated in stress-related disorders. Preclinical studies show that the gut microbiota exerts an influence over neuroimmune and neuroendocrine signaling pathways, in addition to epigenetic modification, neurogenesis, and neurotransmission. In humans, preliminary evidence suggests that the gut microbiota profile is altered in depression. The full impact of microbiota-based treatments, at different neurodevelopmental time points, has yet to be fully explored. The integration of the gut microbiota, as a mediator, in the complex trajectory of depression, may enhance the possibility of personalized precision psychiatry.

        The Role of the Gut-Brain Axis in Attention-Deficit/Hyperactivity Disorder 407

        Sarita A. Dam, Jeanette C. Mostert, Joanna W. Szopinska-Tokov, Mirjam Bloemendaal, Maria Amato, and Alejandro Arias-Vasquez
        Genetic and environmental factors play a role in the cause and development of attention–deficit/hyperactivity disorder (ADHD). Recent studies have suggested an important role of the gut-brain axis (GBA) and intestinal microbiota in modulating the risk of ADHD. Here, the authors provide a brief overview of the clinical and biological picture of ADHD and how the GBA could be involved in its cause. They discuss key biological mechanisms involved in the GBA and how these may increase the risk of developing ADHD. Understanding these mechanisms may help to characterize novel treatment options via identification of disease biomarkers.

        Improving Mental Health for the Mother-Infant Dyad by Nutrition and the Maternal Gut Microbiome 433

        Beatriz Peñalver Bernabé, Lisa Tussing-Humphreys, Hannah S. Rackers, Lauren Welke, Alina Mantha, and Mary C. Kimmel
        Perinatal mood and anxiety disorders (PMAD) have significant negative impacts on mother and child, yet treatments are limited. Adequate nutrition during the perinatal period is essential to maternal and infant health, including maternal mental health and the child’s neurologic and neuropsychiatric development. Nutrition holds promise to improve prevention and treatment of PMAD. The ability to manipulate the gut microbiota composition and structure through host nutrition and to harness the gut microbes for improved individualized nutrition may be an important new direction for prevention and treatment of PMAD, thus improving the mental health of mother and child.

        The Microbiota and Pancreatic Cancer 447

        Tomasz M. Karpiński
        Pancreatic cancer is one of the most lethal diseases. In pancreatic cancer development and progression, genetic (gene mutations and activation of oncogenes) and environmental factors (smoking, alcohol consumption, type 2 diabetes mellitus, obesity) play an essential role. Recently, molecular studies revealed that dysbiosis of microbiota also has influence on cancer development. Research indicates that bacteria and viruses can lead to chronic inflammation, antiapoptotic changes, cell survival, and cell invasion. This review presents bacteria and viruses oncogenic for the pancreas. Possible mechanisms of carcinogenic action are also described.