The gut microbiome refers to the microorganisms that inhabit the human gastrointestinal tract. The gut microbiome begins developing at birth and is influenced by factors like diet, geography, and age. Approximately one third of gut bacteria are common across people, while two thirds vary individually. The gut microbiome plays important roles in digesting food, producing vitamins, protecting against other microbes, and influencing conditions like depression, autism, and schizophrenia through the gut-brain axis. Managing the gut microbiome through prebiotics, probiotics, and diet can positively impact health and disease.

1. Gut Microbiome
LATHA M
2017601306

3. • One third of our gut microbiota is common to most people,
while two thirds are specific to each one of us. In other words,
the microbiota in your intestine is like an individual identity
card.
WHERE CAN WE FIND IT?
• As its name states, gut microbiota is harboured in the intestine,
one of the main areas in our body.
WHEN DOES IT START DEVELPOING?
• The development of gut microbiota starts at birth. From the
third day, the composition of the intestinal flora is directly
dependent on how the infant is fed: breastfed babies’ gut
microbiota, for example, is mainly dominated by
Bifidobacteria, compared to babies nourished with infant
formulas.

5. PROBIOTICS ,PREBIOTICS & SYNBIOTICS

7. Synbiotics
Prebiotics + Probiotics= Synbiotics

9. Composition
-99 % from 30 – 40
species.
• 4 dominant phyla :
- Bacteriodetes.
- Fermicutes.
- Actinobacteria.
- Proteobacteria.
• Enterotypes :
- Prevotella.
- Bacteroides.

11. Variation of Gut Microbiota :
• Dependence on Age
• Dependence on Geography
• Dependence on Diet
Dependence on Age: From pregnancy to eldery
Dependence on Geography: From region to region
Dependence on Diet: Food preference

13. FUNCTIONS

14. Some of the functions are:
• It helps the body to digest certain foods that the
stomach and small intestine have not been able to
digest.
• It helps with the production of some vitamins (B and
K).
• It helps us combat aggressions from other
microorganisms, maintaining the wholeness of the
intestinal mucosa.
• A healthy and balanced gut microbiota is key to
ensuring proper digestive functioning.

16. INFLUENCE ON DISEASES AND
DISORDERS

17. The Gut-Brain Axis
How does the Brain affect the Gut Microbiome?
• This relationship is bi-directional, gut microbiota can
affect the brain and the brain affects gut microbiota
composition.
• Cognitive stress affects mucous secretion in the GI
tract by the release of Noradrenaline which may
stimulate growth of specific Microbes, changing the
gut microbiome.
• Santos et al (2001) looked at maternal separation in
mice in order to study childhood stress and found that
the early stress changed faecal microbiota and gut
microbiota composition by the release of
Noradrenaline. It produced an increase in the gut
microbes; Clostridium Jejuni and Escherichia-Coli

18. How Gut Microbiota affect CNS
function and Neurodevelopment
• Gut microbiota composition is largely influenced by
dietary factors, and these can affect neuron activity in
the CNS.
• Rat studies show that more fermentable
carbohydrates in the diet cause the gut microbes to
increase their fermentative metabolism and increase
fatty acids and lactic acids in the gut which led to
anxiety and aggression in the rat.

19. Schizophrenia
•A disorder that affects a person's ability to think, feel and behave
clearly.
•Lack of microbiota and elevated proinflammatory
cytokines is seen in schizophrenic patients compared to controls.
(Francesconi et al., 2011, and Song et al., 2013)

20. DEPRESSION
•The bidirectional gut-brain
communication axis, showing
increased ACTH, which is often
seen in abnormal levels in
depression.
•It also shows impaired negative
feedback to the adrenal cortex
so this enlarges and produces
more cortisol, leading to
proinflammatory cytokines
which then disrupt the GI tract
and alters microbiome
composition.

21. Serotonin
• Contributor to feelings of well-being and happiness.
• 80% of the human body's total serotonin is located in
the enterochromaffin cells in the gut.
• Aggression, anxiety, appetite, cognition,learning,
memory, mood, nausea, sleep, and thermoregulation.
• Anti-Depressive Drugs: (Venlafaxine
Levomilnacipran) (SSRI : Selective Serotonin
Reuptake inhibitor)
J F Cryan, Nature reviews, Neuroscience, october,2012

22. Bifidobacteria spp. can increase
the concentration of tryptophan
in blood plasma (the precursor
of sereotonin) so act as a
antidepressent.
Desbonnet L, Journal of psychiatric
research, 2008

23. AUTISM
A serious developmental
disorder that impairs the ability
to communicate and interact.

24. • Autistic Children significantly have fewer types
of gut bacteria and significantly lower amounts
of three critical bacteria prevotella, coprococcus
and veillonellaceae.
• These three bacterial groups represent
important strains of carbohydrate degrading and
fermenting microbes.
• So, In may cases the autistic children have IBD
symptoms and they have found that when they
tried to manage the IBD with application of
probiotics the child seems to recover a fewer
percent.
Dae-Wook Kang, PLOS One, July , 2013

25. Celebrate your gut microbiota on the
first World Microbiome day!
• A world without bacteria is, simply, unimaginable. Without
them we probably wouldn’t be here.
• To pay tribute to them, 27th June has been internationally
devoted to bacteria. It is an initiative by APC Microbiome
Ireland, a research institute of the University College Cork
(Ireland). Its developers hope it will become an annual event.
• Its aim is “to showcase the vibrant and diverse worlds of
microbiomes, and to encourage public dialogue on their critical
importance to human, animal and environmental health”. And
they encourage all kinds of microbiome researchers from all
over the world to join and “spread the message of the
importance of microbiomes”.

27. From Next time Don’t feel
Lonely….cause you have some
friends inside you to take care
of yourself……

29. REFERENCES
• http://www.gutmicrobiotaforhealth.com/en/about-
gut-microbiota-info/
• https://www.the-scientist.com/tag/gut-microbiota
• M. Arumugam, J. Raes, E. Pelletier, et
al.Enterotypes of the human gut microbiome
Nature, 473 (2011), pp. 174-180
• N. Ottman, H. Smidt, W.M. de Vos, et al.The
function of our microbiota: Who is out there and
what do they do?Front Cell Infect Microbiol (2012),
p. 104
• Andrew B. Shreiner1, John Y. Kao1, and Vincent
et al. The gut microbiome in health and in disease