Gut Microbiota and Gastrointestinal Disorders

In recent years, a large body of scientific community and literature has proposed that certain alterations of the gut microbiota composition may be associated with the development and pathogenesis of several gastrointestinal disorders including, inflammatory bowel disease, irritable bowel syndrome, non-alcoholic fatty liver disease, obesity, type 2 diabetes mellitus, celiac disease, gastrointestinal cancers and Clostridioides difficile infection. These alterations are often referred to as “gut dysbiosis”, a generic name describing imbalance of gut microbiota biodiversity, and disturbance in its composition and structure. In many cases, dysbiosis is associated with increased abundance of pathobionts taxa with potential pathogenic activity, and at the expense of a reduced representation of taxa with possible beneficial metabolic activity. Dysbiosis is also associated with reduced biodiversity, and lower complexity of the microbial species present in the microbiome. Therefore, the gut microbiota dysbiosis can influence the human health and pathology at different levels and the abnormality of the microbiota composition can be both cause and consequence of a state of disorder.

In the last decade, many studies have focused on identifying the key abnormalities of gut microbiota associated with various acute and chronic gastrointestinal diseases, and exploring how these changes in the microbiota composition can be linked to the pathogenesis of the gastrointestinal disorders. Moreover, advanced multi-omics technologies might help decipher the roles and mechanisms of gut microbiota on hosts in both health and disease conditions. However, the precise roles and functions of certain species of human gut microbiota in development and pathogenesis of various gastrointestinal disorders remain unclear.

The aim of this Research Topic is to publish Original Research and Review articles that may provide new insight into:

• Human and animal studies on the gut microbiota alterations and gastrointestinal disorders, not only focused on bacterial microbiota but also viral microbiota and mycobiota.
• Novel key microbiota signatures that are associated with gastrointestinal cancers and inflammatory diseases.
• Multi-omics research on the mechanisms involved in the pathogenesis of gastrointestinal disorders targeting the gut microbiota in animal models.
• The roles and mechanisms of intestinal pathobionts on gastrointestinal disorders in human and animal studies.
• The effect of specific gut microbiota species and its metabolic activity on local and systemic immune response and function associated with gastrointestinal cancers and inflammatory diseases.