Microbial modulation of
diabetes (type 2)
Short-chain fatty acids (SCFAs) are produced
by various human gut microbes. SCFAs act as an energy source to the colonic
epithelium and are also sensed by host signaling pathways that modulate
appetite and inflammation. Deficiency of gut SCFAs is associated with type 2
diabetes. Zhao et al. found that adopting a high-fiber diet
promoted the growth of SCFA-producing organisms in diabetic humans. The
high-fiber diet induced changes in the entire gut microbe community and
correlated with elevated levels of glucagon-like peptide-1, a decline in
acetylated hemoglobin levels, and improved blood-glucose regulation.
Gut bacteria selectively promoted by dietary
fibers alleviate type 2 diabetes
Science 09 Mar 2018:
Vol. 359, Issue 6380, pp. 1151-1156
DOI: 10.1126/science.aao5774
Vol. 359, Issue 6380, pp. 1151-1156
DOI: 10.1126/science.aao5774
Ann Med. 2017
Feb; 49(1):11-22. doi: 10.1080/07853890.2016.1222449. Epub 2016 Nov 29.
Is
there a role for gut micro biota in type 1 diabetes pathogenesis?
Author information
Abstract
Type 1 diabetes mellitus (T1D) is an autoimmune disease
characterized by insufficient insulin production due to the destruction of
insulin secreting β-cells in the Langerhans islets. A variety of factors,
including chemicals, viruses, commensal bacteria and diet have been proposed to
contribute to the risk of developing the disorder. In the last years, gut micro
biota has been proposed as a main factor in T1D pathogenesis. Several
alterations of gut microbiota composition were described both in animal model
and in humans. The decrease of Firmicutes/Bacteroides ratio was the most frequent
pattern described, in particular, in human studies. Furthermore, Bacteroides,
Clostridium cluster XIVa, Lactobacillus, Bifidobacterium, and Prevotella
relative abundances were different in healthy and affected subjects. Dysbiosis
would seem to increase intestinal permeability and thus promote the development
of a pro-inflammatory niche that stimulates β-cell autoimmunity in predisposed
subjects. Preliminary studies on animal models were realized to investigate the
role of gut microbiota modulation as therapy or prevention approach in
predisposed animals: promising and stimulating results have been reported. Key
message Dietary antigens and microbiota-derived products might act as triggers
of T1D by causing a pro-inflammatory and metabolic dysfunctional environment.
I remember my colleagues laughing at me in 2005 when I
expressed my opinion that Diabetes 1 and 2 are inflammatory manifestations and
that many of the measurements such as Cholesterol were just inflammatory
markers. Microbiome understanding was just surfacing at that time.
Now they are not laughing, both Type 1 and Type 2 Diabetes
in susceptible people have been associated with Microbiome changes in diversity
and that treatment may include methods of increasing the diversity.
This is the advantage of doing Clinical Work exclusively
among a single cultural racial group such as American Indians in my case. Your
desire to alleviate some of their suffering would lead you to think
in innovative fashion about the origins of metabolic diseases among this group.