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248 Cardio Diabetes Medicine 2017

Listening to Our Gut:

Microbiomes and NCD /CVD

Dr. Rajesh Upadhyay,

Director & Head, Department of Gastroenterology & Hepatology
Max Superspeciality Hospital, Shalimar Bagh, Delhi

Human microbiota contains 10-100 trillion microbial and Lactobacillus is seen in children with Type I dia-
cells (37 trillion total cells in human body) with >1000 betes mellitus. Such children also have lower counts
species.Bacteroidetes and Firmicutes are dominant of butyrate producing bacteria. A clear relationship
(>90% of the total microbial population) in human in- has been demonstrated between T2D and composi-
testine. Each individual has a unique set of intestinal tional changes in the gut microbiota. There is a low-
microbiota, the formation of which starts at the time er relative abundance of Firmicutes, Bifidobacterium
of birth and is dependent on a number of factors and Faecalibacterium (anti-inflammatory) and a high-
such as – genetic, environmental and immunological er proportion of Bacteroidetes and Proteobacteria in
status. Diet has an important role in the composition diabetics. Diabetics also have a significantly lower
of these bacteria. The microflora subserves import- number of butyrate producing bacteria.Changes of
ant functions in human body such as protective from gut microbiota composition are strongly associated
pathogens, trophic functions e.g. control of epithelial with increased adiposity, β-cell dysfunction, metabol-
cell proliferation /differentiation/ development and ic endotoxemia, systemic inflammation, and oxida-
homeostasis of the immune system and metabolic tive stress associated with T2DM.Improvement of gut
functions e.g. fermentation of non-digestible dietary microbiota leads to stimulation of insulin signalling,
residue and endogenous mucus, salvage of energy B cell preservation, regulation of insulin secretion, fat
(as short-chain fatty acids) and absorbable nutri- accumulation, cholesterol levels and has anti-inflam-
ents. The mechanisms include production of antimi- matory effect.
crobials, destruction of toxin receptors, competitive Bifidobacterium and Lactobacillus strains have been
exclusion of pathogens, organic acid production, most widely used in animal and clinical studies with
enhanced intestinal barrier function, enhanced IgA diabetes.A number of studies have shown that probi-
secretion and immune regulation.
otic supplementation significantly decreases fasting
The microbiota are in symbiosis with the host but a blood glucose andHbA1c levels in diabetic patients.
number of environmental factors such as diet, med- L. acidophilus La-5 and B. animalis subsp. lactis BB-
ications, antibiotics etc. can lead to dysbiosis. The 12 administration has been evaluated on T2D pa-
imbalance (dysbiosis) has been associated with a tients.There was a significant difference between
number of gastro intestinal diseases. Recently, re- groups concerning mean changes in the HbA1c, TC
searchers have proposed that metabolic disorders and LDL-C levels. In addition, an increase in HDL-C
might result from alteration in gut microbiota com- levels and a decrease in the LDL-C/HDL-C ratio in
position. Dysbiosis has been linked to diseases such the intervention group. A number of other studies
as diabetes, hypertension, dyslipidemia and cardio- have also shown beneficial effects of probiotics in
vascular diseases. diabetics but the studies are small and not very well
designed. Further large well designed studies with
The hypothesis that bacterial endotoxemia may be
an important factor in causation of insulin resistance specific probiotics compositions are required before
and diabetes has been subject of large number of recommending in routine clinical practice.
studies. Higher counts of Clostridium, Bacteroides Obesity is a metabolic disorder. There is a growing
and Veillonella and lower counts of Bifidobacterium evidence that gut microbiota have an important role

GCDC 2017