Dr. Sanaa Youssef MD Pediatrics

24-9-2010

The Science of Nutrition

= The Art of Caring

Understanding Updates about

the Rediscovery of the Human GIT

Highlighting the importance and function

New Emerging Ingredients

(PRObiotics – PREbiotics)

My audience will STILL be AWAKE by the end of the

talk.

Goals of This Talk

The Rediscovery of the

INNER TUBE OF LIFE

the Human GIT

The intestine is an extremely complex system that participates in protection of the host through strong defense mechanisms from the external environment;

Defense task is based on three compartments that are in permanent contact and dialogue with each other:

1- The ecological barrier (normal inhabitant flora within intestine)

2- Mechanical barrier (mucous epithelia)

3- Immune barrier (GALT, secretory IgA, intraepithelial lymphocytes, macrophages, neutrophils, natural killer cells, Payer’s nodes and mesenteric lymph node) (Mohajer, 2000)

Our Intestine = 400 square meter surface…

i.e. the surface area of a tennis court

INNER TUBE OF LIFE

The colon Is a part of the body's digestive

system (about six feet long) that moves waste material from the small intestine to the rectum.

Little was known about colonic functions.Many thought that the colon was a colander that

strained the feces.

Later Accepted ROLES about colonic functions :Conservation of water and electrolytes Control evacuation of faeces

INNER TUBE OF LIFE

Historical Facts

Recent researches demonstrated the importance of the colon as a metabolic organ with an influence on overall metabolism, an effect that is attributed to activity of Microflora the role of which was Underestimated.

New studies revealed: The role played by microbiota in the colon. Functions of different mucosal epithelial cells of the

colon.(Immunocompetent cells) The mucosal hydrophobicity of the colon.(A Lugea et al,Gut

2000;46:515-521 doi:10.1136/gut.46.4.515 )

INNER TUBE OF LIFE

Advances in understanding Colonic function

Battles are Fought, Helpful Substances are

Manufactured,& The immune system is

Bolstered.

Did you know that in the “COLON World”….!!!??

Trillions living bacteria exist in the human intestine

We have more bacteria in our bodies (10 times greater) than the total number of our somatic and germ cells We carry about 2 kg of bacteria !!!!!!!!

Over 500 species of bacteria present in human colon.

Lactobacillus Bifidis and Acidophilus comprise the majority of healthy bacteria in the colon along with other disease producing bacteria.

Where “Man Meets Microbe”A Dynamic Interplay

HCL

1- Short Transient Time2- Bile milieu3- Pancreatic secretion4- ph = 7 (neutral)

Mucous, cells…..

Prevents bacterial reflux

Ileo-ceocal valve

Where “Man Meets Microbe”A Dynamic Interplay

Our gut Microbiota can be pictured as a

MICROBIAL ORGAN

placed within a host organ

Where “Man Meets Microbe”A Dynamic Interplay

The very rapidly developing immune system begins from birth up to 2 years.

It starts with creating a healthy digestive system which plays a major role from infancy and throughout all our life (about 80% of our immune system is found in the GIT)

“ This immature immune system

needs special measures for its

Protection and Support.”

“The intestine is not only a digestive absorptive organ but it is the

largest immune organ in our body.”

Sharing My Secrets of Health

The gastrointestinal tract of a normal fetus is sterile.

During the birth process: the aseptic or sterile, digestive tract of the fetus is inoculated with bacteria (proximity of the birth canal and the anus).

Rapidly thereafter, effective methods of ensuring transmission of microbes to the sterile GIT:o parental expression of neonatal care: suckling, kissing and

caressing (mother’s flora) o Genetic factor o surrounding environment o Feeding pattern: the first biggest challenge is one the

intestine becomes inhabited by microbes which are characterized by instability and fragility. Later the microbiota will stabilize according to the type of feeding.

Early In Life ???

The first colonization of the intestine is one of the most profound immunological exposures faced by the newborn infant (during the first days of life).

The next great changes in the composition of the intestinal microbiota come with the introduction of solid food and weaning (Favier et al., 2002).

Hygiene Hypothesis: Decreased bacterial stimulation during infancy and childhood is asscociated with slower postnatal development and delayed maturation of the immune system. (L.E.M. Niers et al., 2005)

Relatively small changes will take place by after years of age where the child will have an adult-like microbiota and then it remains practically unchanged (Zoetendal et al., 2008).

Early In Life ???

New Perspective

In INFANT NUTRITION

Probiotics and Prebiotics share a unique role in human nutrition.

Research has shown that Probiotics and Prebiotics are useful in achieving positive health effects and well being to the host.

New emerging dietary ingredients

PRObiotics microorganisms which confer health

benefits on the host”, when administered in adequate amounts. (Marco ML et al,2006)

Probiotic is not a synonym for native beneficial bacteria, although they may be isolated from this source.

They should be identified by genus, species and when appropriate by strain when supplemented.

The term “probiotic,” by definition, can

never be used to describe products

comprised primarily of Dead Bacteria.

“LIVE”

(Journal of the American Dietetic Assosciatio,2008)

Probiotics are sensitive in a strain-dependent manner

to environmental exposures such as heat, moisture,

oxygen, and acid. Once the package is opened, these

barriers are compromised.

The doses should reflect any losses inherent to the

probiotic as it moves through the alimentary canal.

When wishing to deliver their benefits (Immune

enhancement) dose should be adjusted according to

the strain and better increased level of the Probiotic

should be considered because of the losses.

PRObiotics

(Journal of the American Dietetic Assosciatio,2008)

• They Only Transiently colonize the Gut and do not typically become part of the permanent resident micro flora of the host.

NO Statement

should generally refer to

Probiotics as “Efficacious or Safe”;

this would be as inappropriate as stating

Antibiotics in general are “Efficacious and Safe”.

PRObiotics

(Journal of the American Dietetic Assosciatio,2008)

The term prebiotic was introduced by Gibson and Roberfroid 1995 who exchanged “PRO" for “PRE" which means “Before“.

‘A prebiotic is a selectively fermented ingredient that allows specific changes, both in the composition and ⁄ or activity in the gastrointestinal microbiota that confers benefits upon host well-being and health.’(Gibson et al., 2004)

“Nutriceuticals” or “Biotherapeutics” or “Prebiotics”= substances or supplements administered to obtain nutraceutical effects that extend “beyond those of regular nutrition.”

PREbiotics

(Journal of the American Dietetic Assosciatio,2008)

Facts about PREbiotics

Prebiotics; are simply speaking the preferential “FOOD” for Friendly Beneficial Bacteria colonizing

the digestive tract.

“colonic food” They are dietary supplements that play a role in Balancing the Intestinal Mucosal Immune System in

newborns and children.

1) Resistance to gastric acidity, to hydrolysis by mammalian enzymes, and to gastrointestinal absorption;

2) Selective stimulation of the growth and/or activity of those intestinal bacteria that contribute to health and well-being

3) Fermentation by intestinal microflora; to produce SCFA & gas.

4) Induce LUMINAL or SYSTEMIC beneficial effects.

Criteria for eligibility as PREbiotic (Gibson et al., 2007)

Established PREbioticsBreast Milk oligosaccharides Original they represent the

third largest component of Human Milk 20 - 23 gm/l in colostrum & 12- 14 gm/ in mature milk.

Polydextrose – Fructans Inulin Wheat, banana, onions, garlic, leek, chicory.

FOS (Fructo-oligosaccharides or oligofructose) plants.

GOS (Galacto-oligosaccharides) milk.

(also known as TOS – trans-galacto-oligosaccharides) Lactulose - Lactosucrose SOS (soy-oligosaccharides) XOS (xylo-oligosaccharides) IMO (isomalto-oligosaccharides) corn & wheat.

Lactitol (Journal of the American Dietetic Assosciatio,2008)

SyMbiosis

Symbiosis

(Greek: syM "with"; & biosis "living") The term was first used in 1879 by the German mycologist

Heinrich Anton de Bary, who defined it as "the living together of unlike organisms.“

Commensalism is a class of relationship between two organisms

There are two associations:

Mutualism: (facultative) both organisms benefit

Parasitism: (obligate) one organism benefits and the other one is harmed.

SyMbiosis

“Intestinal Microbiota is an example of

A symbiotic relationship

with the host”

SyMbiosis

Host-Bacteria interaction responsible for the effectiveness of gut immune related mechanisms.

POSTbiotics

SCFA

Short chain fatty acids (SCFAs) are the products of colonic bacterial degradation of unabsorbed starch and non-starch polysaccharide (fibre).

The main acids: Acetate, Propionate, and Butyrate and Lactic acid. They are important anions in the

colonic lumen, affecting both

Colonocyte Morphology (Proliferation / Differentiation)

& Function (Tight Colonic Junction

/ Inflammatory Suppression).

POSTbiotics

Butyrate is the preferred energy substrate for the colonocyte, it provides fuel (nutrition) for ileal and colonic epithelial cells, which help maintain the integrity of the colon.

LOW Resistant Starch & Fiber Diet low SCFA production in colon explain the high occurrence of colonic disorders.

Safe Alternative Therapeutic Strategy ???????

SCFA support the critical Gut mucosal barrier: Keeping Gut integrity

• SCFA facilitate the absorption of water and electrolytes that in turn helps minimizing the risk of diarrhea as well as its volume.

• Acetate increases colonic blood flow and enhances ileal motility.

• SCFA may be involved in the:

Ileo - Colonic Brake”

Stimulates contractions of the ileum and shortens ileal emptying.

SCFA help improve Water & Electrolyte Absorption

and Bowel Movement

DYSBiosis

Dysbiosis is the abnormal microbial colonization of the intestine , where changes in Quantity and Quality of flora become Pathological & Harmful.

When intestinal flora equilibrium is disturbed, the optimum expected health effects are lost autoimmune conditions result (IBD, rheumatoid).

A common cause of dysbiosis is antibiotic therapy (Iatrogenic).

DYSBiosis

Thank your for your patience

1. American Journal of Clinical Nutrition, Vol. 69, No. 5, 1035S – 1045S, May 1999.

2. Gastroenterology and Nutrition in infancy (GNI).3. International Food Information Council (IFIC).4. International Food Information Foundation’s Media Guide on Food Safety and

Nutrition.5. Nutrition Information Centre University of Stellenbosch (NICUS).6. HEALL: Health Education Alliance for Life and Longevity.7. Can J Gastroenterol. 2004 Mar;18(3):163-7 Redefining lactose as a conditional

prebiotic. 8. Daniells, Stephen, Prebiotics Could Reduce Artery Hardening, Boost Heart

Health, NutraIngredients.com, 2 January 2007. 9. Hamilton-Miller, JMT, Probiotics and Prebiotics in the Elderly, 20 January

2004.10. Marco ML et al; Towards understanding molecular modes of probiotic action. Curr Opin Biotechnol 2006; 17:204–210.

References

11. Prebiotics Could Improve Heart Health, NPICenter.com, 22 December 2006.

12. Saavedra, J.M. and Tschernia, A., Human Studies With Probiotics and Prebiotics: Clinical Implications, British Journal of Nutrition, Volume 87, Supplement s2, 1 May 2002, pp. 241-246(6).

13. Rodrigo B., Mathieu M., Chieh J. : Gut Microbiota, Obesity and Diabetes; (1/2009) Annales Nestle.

14. Roberfroid MB : Prebiotics and probitoics are they functional ? Am J Clin Nutr; (2000) 71: 1470-1481.

15. Ley RE, Backhed F, Turnbaugh P, et al: Obesity alter gut microbial ecology. Pro Natl Acad Sci USA 2005;102: 11070-11075.

16. Turnbaug PJ, Backhed F, Fulton L, Gordon JI: Diet –induced obesity is linked to marked but reversible alteration in mouse distal gut microbiome. Cell Host Microbe 2008; 3: 213-223.

17. Weickert MO, Pfeiffer AF: Metabolic effects of dietary fiber consumption and prevention of diabetes. J Nutr 2008;138:439-422.

References