Diseases / Disorders (extraintestinal manifestations)

For many diseases that are extraintestinally manifested, a connection with the human microbiota, especially the gut microbiota, is suspected or considered to be certain.

Mood and behavior are also susceptible to alterations in the gut microbiota
Postler & Ghosh 2017

The microbiota also exerts systemic effects through mechanisms that are less well understood than those mediating the local effects
Roy & Trinchieri 2017

Since gut microbial metabolites circulate throughout the host’s body, it has become increasingly recognized that gut microbiota are involved in the pathogenesis of diseases not only in the intestine but also in distant organs. For instance, we recently discovered that metabolites from obesity-induced gut microbiota promoted liver cancer and elucidated the underlying molecular mechanism.
Ohtani 2015 Semin Immunopathol 37(1): 65-72

Bacterial Polysaccharide A (PSA) mediates gut homeostasis by directing the cellular and physical development of the immune system, stimulates Tregs via plasmacytoid dendritic cells (PDCs), and protects animals from experimental diseases such as colitis, asthma, or pneumonia and experimental autoimmune encephalomyelitis (EAE).

The polysaccharide-experienced effector T cells induce Interleukin-10 (IL-10) in FoxP3+ regulatory T cells. This action helps to prevent pulmonary inflammation.
The plasmacytoid dendritic cells mediate anti-inflammatory responses to a gut commensal molecule through both innate and adaptive mechanisms. The bacterial capsular polysaccharide prevents the onset of asthma through the activation of T-cells. The human commensal Bacteroides fragilis produces a polysaccharide that offers protection against central nervous system demyelinating disease.
Mazmanian et al. 2005
Ochoa-Reparaz et al. 2010 Mucosal Immunol. 3: 487-495
Round & Mazmanian 2010
Dasgupta et al. 2014 Cell Host and Microbe. 15: 413-423
Wang et al. 2014 Nat Commun 5: 4432
Johnson et al. 2015 Glycobiology 25: 368-75
Johnson et al. 2018 Glycobiology 28: 50-8
Erturk-Hasdemir et al. 2019 Proc Natl Acad Sci USA 116: 26157-66

see also:
Diseases / Disorders & Gut microbiota
Gut microbiota & Immune Checkpoint Inhibitors (ICIs)
Gut microbiota & Multiple sclerosis (MS)
Fecal Microbiota Transplantation (FMT) (procedure-based) & Preclinical/Clinical data
Leaky Gut Syndrome / Leaky Gut
Prebiotics & Preclinical /Clinical data
Probiotics (living agents) & Preclinical/Clinical Data
Synbiotics & Preclinical/Clinical data
Systemic Inflammation