The document discusses the role of probiotics in pediatric practice, emphasizing their importance in shaping the infant microbiome and immune system development. It details the definitions, mechanisms of action, and criteria for effective probiotics, focusing on specific strains like Lactobacillus and Bifidobacterium, which benefit gut health. The take-home message highlights that gut microbiota is crucial for health and can be influenced by diet and lifestyle choices.

1. Probiotics in Pediatric Practice
By Dr Rashmin Cecil
Basics to Beyond

2. INDEX
Short layout of our journey!
● Introduction
● Definitions
● Physiology
● Disturbance in Physiology
● Mechanism of action
● Criteria for ideal probiotic
● Commonly studied &
used
● Points to ponder
● Take home message

3. Introduction

4. Introduction
● The microbiome plays a major part in human health through intimate
interaction with our body.
● The gastrointestinal microbiota constitutes the largest part of the human
microbiome.
● Intentional manipulation of host microbes with a therapeutic operation of
treating many diseases is an area of great interest.
● Probiotics and prebiotics have the potential benefits of altering the microflora of
the host potential for benefitial health.

5. Definitions

6. Probiotic
The term probiotic is derived from the Latin
preposition “pro,” which means “for” and the
Greek word “biotic” meaning “bios” or “life”
They are defined as “live microorganisms which
when administered in adequate amounts confer a
health benefit on the host”.

7. Prebiotic
Prebiotics are nondigestible food ingredients that
benefit the host by selectively stimulating the
growth or activity of one or a limited number of
bacteria in the colon.

8. Gut flora or Gut microbiota
The microorganisms including bacteria, archaea
and fungi that live in the digestive tracts of
humans and other animals including insects.
The gastrointestinal metagenome is the
aggregate of all the genomes of gut microbiota.
The gut is the main location of human
microbiota. This domain is exciting and
emerging areas of research

9. Microbiome
The term microbiome was initially used to refer to the
collection of genes harbored by microorganisms.
A broad definition of microbiome encompasses “the entire
habitat, including the microorganisms (bacteria, archaea,
lower and higher eukaryotes, and viruses), their genes,
and the surrounding environmental conditions.”

10. Symbiosis
A symbiosis is an evolved interaction or
close living relationship between
organisms from different species,
usually with benefits to one or both of
the individuals involved.

11. Dysbiosis
Dysbiosis (also called dysbacteriosis) is
a term for a microbial imbalance or
maladaptation on or inside the body,
such as an impaired microbiota.
A commensal is an organism that uses
food supplied in the internal or the
external environment of the host,
without establishing a close association
with the host, for instance by feeding on
its tissues.

12. Spores
A minute, typically one-celled, reproductive unit.
It’s a reproductive cell capable of developing into a
new individual without sexual fusion with another
reproductive cell.
Spores are agents of asexual reproduction, whereas
gametes are agents of sexual reproduction.
Spores are produced by bacteria, fungi, algae, and
plants.

13. Archaea constitute a domain of single-celled organisms.
These microorganisms lack cell nuclei and are therefore
prokaryotes.
Archaea were initially classified as bacteria, receiving the
name archaebacteria, but this classification is obsolete
Archaea

14. Physiology

15. Biotics in neonatal development
● Microbial colonization of the infant GI tract
"The microbes that colonize mucosal tissues after birth
play a pivotal role in shaping the development of the host
immune system"
● Mode of delivery determines early intestinal
colonization
“There is accumulating evidence that intestinal bacteria
play an important role in the postnatal development of
the immune system"

16. Vaginal delivery

17. Cesarean delivery

18. The intestinal tract of the infant
● Not mature at the time of birth
● The largest surface area that is exposed to the
environment, especially a vast array of luminal
microbes and antigens
● The mucosal immune system represents about 80%
of the infant's immune system
● The development of the infant's immune system is
closely related to the intestinal microbiota
● "The immune system undergoes major development
during infancy, and the development is highly related
to the microbes that colonize the intestinal tract"

19. How does the infant acquire his/her
microbiome?
Before birth the gut is sterile
Colonization due to exposure to vaginal microflora
Supplemented by bacteria contained in breast milk and
skin bacteria

20. Cesarean delivery
Lack of exposure to vaginal microflora
Abnormal seeding of GI tract with environmental flora,
food flora
Difference in microbiome detectable up to one year
Abnormal development of immunity

21. What is the microbiome of the infant?
There is not a "normal" microbiome
But we can describe the microbiome of a breastfed full-
term infant who was born vaginally
It consists nearly exclusively of Lactobacilli and
Bifidobacteria

22. Microbiota of the breastfed infant
Lactobacillus Bifidobacterium

23. Microbiota of the breastfed infant
● The infant receives a constant supply of
gram+bacteria (milk, skin)
● Human milk provides oligosaccharides that favor
bifidobacteria and lactobacilli
● Human milk contains immunoglobulin A
● Together they suppress undesirable bacteria and
pathogens
● Human milk contains live bacteria
● Human milk contains oligosaccharides that favor
good bacteria and inhibit bad bacteria
● Development of immunity differs

24. Microbiota of the infant
I. The good guys: Lactobacilli and
Bifidobacteria(fucose-consuming bacteria)
II. The not so good guys: All others (E. coli,
Clostridia)including pathogens

25. Early Infancy is a Critical Period for Intestinal
Microbial Development
A healthy gut begins
with the introduction
and colonization of the
right microbes and this
foundation is laid over
a short period of time
during fetal
development, birth,
and early infancy.
Factors that Impact Optimal
Microbial Colonization

26. Change In Gut Biodiversity With Influencing
Factors

27. Disturbance in
Physiology

28. Insufficient microbial colonization of the intestinal
tract can result in episodic or short-term
consequences such as-

29. Mechanism of action

30. Mechanisms of action in probiotics
Major probiotic mechanisms of action include
1. Enhancement of the epithelial barrier,
2. Increased adhesion to intestinal mucosa
3. Concomitant inhibition of pathogen adhesion
4. Competitive exclusion of pathogenic microorganisms
5. Production of anti-microorganism substances
6. Modulation of the immune system

31. Mechanism of action of Probiotics

32. They exert their activity primarily by strengthening
the intestinal barrier and immunomodulation.
Once the probiotic adheres to the cell, various
biological activities take place, which primarily
include the release of cytokines and chemokines.
These then exert their secondary activity such as
stimulation of mucosal and systemic host immunity

33. Antimicrobial Effects of Probiotics.
● Modify microflora to suppress pathogens.
● Secrete antibacterial substances. Probiotic bacteria
produce a variety of substances that are inhibitory to
both gram-positive and gram-negative bacteria. These
include organic acids, hydrogen peroxide and
bacteriocin. These compounds may reduce not only the
number of viable pathogenic organisms but may also
affect bacterial metabolism and toxin production.
● Compete with pathogens to prevent their adhesion to
the intestine.
● Compete for nutrients necessary for pathogen survive.
Antitoxin effect

34. Effect of Probiotics on the Intestinal
Epithelium.
I. Promote tight contact between epithelial cells
forming a functional barrier.
II. Reducing the secretory and inflammatory
consequences of bacterial infection.
III.Enhancing the production of defensive molecules
such as mucins.

35. Immune Effects of Probiotics
I. Probiotics as vehicles to deliver anti-inflammatory
molecules to the Intestine.
II. Enhance signaling in host cells to reduce
inflammatory response.
III.Switch in immune response to reduce allergy.
IV.Reduce the production of inflammatory substances.

36. Criteria for ideal
probiotic

37. Qualities of effective probiotic dietary
supplement include the following:
● Must be for human consumption
● Exert a beneficial effect on the host
● Be non-pathogenic and nontoxic
● Contain a large number of viable cells
● Be capable of surviving and metabolizing in the gut
● Remain viable during storage and use
● Be antagonistic to pathogens

38. Commonly studied and
used

39. Most commonly studied Probiotics
● Lactobacillus
● Bifidobacterium
● Sacchromyces Boulardii
● Bacillus subtilis
● Bacillus Clausii

40. Lactobacillus rhamnosus GG is a strain of L. rhamnosus that
was isolated in 1983 from the intestinal tract of a healthy
human being; filed for a patent on 17 April 1985, by Sherwood
Gorbach and Barry Goldin, the 'GG' derives from the first
letters of their surnames.
The patent refers to a strain of "L. acidophilus GG" with
American Type Culture Collection (ATCC) accession number
53103; later reclassified as a strain of L. rhamnosus.
The patent claims the L. rhamnosus GG (ATCC 53103) strain
is acid- and bile-stable, has a great avidity for human intestinal
mucosal cells, and produces lactic acid.

41. I. Increased adhesive capacity
II. LrGG biofilm persists longer and in higher
concentration compared to other lactobacilli
III.LrGG colonisation capacity is better in newborns
IV.Less colonisation resistance in the gut
V. LrGG is recovered from tonsils, vagina and oral
cavity after oral therapy
VI.Gut colonisation lasts longer than fecal recovery as
detected from colonic biopsies

42. Indications
GI Disorders
AAD
Viral Gastroeneritis
NEC
IBD
Non GI disorders
URTI
Eczema
Otitis media

43. Points to ponder

44. Points to Ponder
I. In humans, there are about as many bacterial cells as
there are human cells.
II. Gut bacteria have 150 to 200 times more genes than
the human genome.
III.Gut microbiota richness, diversity and stability over
time are key features of a health-associated human
gut microbiome.

45. Take home message

46. Take Home Messages
I. Your gut is more than a tube. It’s home to more than
100,000 trillion microorganisms that participate in
the digestion and defense functions of the
gastrointestinal tract.
II. They could also be involved in mental health.
III.Like your fingerprint, your gut microbiota
composition is unique to each individual

47. I. External factors can affect your gut microbiota.
II. While some are less controllable (e.g. genetics,
delivery methods, geography and aging), you can act
on your diet and lifestyle to help your gut microbiota
work properly.
III.What you eat doesn’t only nourish you; it also feeds
the trillions of microorganisms that live in your gut.
IV.Include prebiotic fibers and fermented foods with
probiotics, as you make progress on the path towards
a healthy gut.

48. Thank You !