The gut microbiota and inflammatory noncommunicable diseases: associations and potentials for gut microbiota therapies

Rapid environmental transition and modern lifestyles are likely
driving changes in the biodiversity of the human gut microbiota.
With clear effects on physiologic, immunologic, and metabolic
processes in human health, aberrations in the gut microbiome
and intestinal homeostasis have the capacity for multisystem
effects. Changes in microbial composition are implicated in the
increasing propensity for a broad range of inflammatory
diseases, such as allergic disease, asthma, inflammatory bowel
disease (IBD), obesity, and associated noncommunicable
diseases (NCDs). There are also suggestive implications for
neurodevelopment and mental health. These diverse
multisystem influences have sparked interest in strategies that
might favorably modulate the gut microbiota to reduce the risk
of many NCDs. For example, specific prebiotics promote
favorable intestinal colonization, and their fermented products
have anti-inflammatory properties. Specific probiotics also have
immunomodulatory and metabolic effects. However, when
evaluated in clinical trials, the effects are variable, preliminary,
or limited in magnitude. Fecal microbiota transplantation is
another emerging therapy that regulates inflammation in
experimental models. In human subjects it has been successfully
used in cases of Clostridium difficile infection and IBD, although
controlled trials are lacking for IBD. Here we discuss
relationships between gut colonization and inflammatory NCDs
and gut microbiota modulation strategies for their treatment
and prevention. (J Allergy Clin Immunol 2015;135:3-13.)