Gut Microbiota Alteration and Its Modulation with Probiotics in Celiac Disease.

Celiac disease (CD) is a chronic inflammation of the small intestine triggered by gluten ingestion in genetically predisposed people. Recent literature studies highlight the possible role of the gut microbiota in the pathogenesis of this disease. The gut microbiota is a complex community of microorganisms that can interact with the innate and adaptative immune systems. A condition of dysbiosis, which refers to an alteration in the composition and function of the human gut microbiota, can lead to a dysregulated immune response. This condition may contribute to triggering gluten intolerance, favoring the development and/or progression of CD in genetically susceptible patients. Interestingly, studies on children and adults with CD showed a different microbiome profile in fecal samples, with a different degree of "activity" for the disease. From this point of view, our review aimed to collect and discuss modern evidence about the alteration of the gut microbiota and its modulation with probiotics, with possible future indications in the management of patients affected by CD.

Intestinal Damage, Inflammation and Microbiota Alteration during COVID-19 Infection.

BACKGROUND: The virus SARS-CoV-2 is responsible for respiratory disorders due to the fact that it mainly infects the respiratory tract using the Angiotensin-converting enzyme 2 (ACE2) receptors. ACE2 receptors are also highly expressed on intestinal cells, representing an important site of entry for the virus in the gut. Literature studies underlined that the virus infects and replicates in the gut epithelial cells, causing gastrointestinal symptoms such as diarrhea, abdominal pain, nausea/vomiting and anorexia. Moreover, the SARS-CoV-2 virus settles into the bloodstream, hyperactivating the platelets and cytokine storms and causing gut-blood barrier damage with an alteration of the gut microbiota, intestinal cell injury, intestinal vessel thrombosis leading to malabsorption, malnutrition, an increasing disease severity and mortality with short and long-period sequelae. CONCLUSION: This review summarizes the data on how SARS-CoV-2 effects on the gastrointestinal systems, including the mechanisms of inflammation, relationship with the gut microbiota, endoscopic patterns, and the role of fecal calprotectin, confirming the importance of the digestive system in clinical practice for the diagnosis and follow-up of SARS-CoV-2 infection.