PROBIOTICI E PREBIOTICI PER IL MICROBIOTA UMANO

Patrizia BrigidiDept. Pharmacy and Biotechnology

University of Bolognapatrizia.brigidi@unibo.it

THE HUMAN INTESTINAL MICROBIOTA

the 1014 bacterial mutualists (10 x our total cell number) which inhabit our GIT constitute the human intestinal microbiota

• 1012 CFU/g• up to 1.5 kg

the most dense bacterial ecosystem on our planet

> 1000 species

5 (out of 100) bacterial phyla•Firmicutes (65%), Bacteroidetes (25%)•Actinobacteria (5%), Proteobacteria (<8%), Fusobacteria (1%) and Verrucomicrobia (1%)

PHYLOGENETIC STRUCTURE

FUNCTIONAL DIVERSITY

MICROBIOME 106 GENES

58% KNOWN 42% UNKNOWN • carbohydrate metabolism (CAZymes)• energy metabolism• amino acid metabolism• biosynthesis of secondary metabolites• metabolism of cofactors and vitamins

MICROBIOTA-HOST MUTUALISM, ECOLOGICAL SERVICES

our bacterial counterpart provides essential features we have not evolved

IMPACT ON HOST NUTRITION

indigestible plant polysaccharides (xylan, pectin, arabinose containing-dietary carbohydrates as plant-derived pectin, cellulose, hemicellulose, resistant starches)

reach unchanged the colon where they are metabolized by the intestinal microorganisms

equipped with a real arsenal of CAZymes – absent in human genome –intestinal microorganisms degrade plant polysacchar ides to SCFA

SCFAkey microbiota metabolites

regulating the host nutritional status

indigestible plant polysaccharides

SCFA, MICROBIAL METABOLITES WITH A KEY MULTIFACTORIAL ROLE IN HOST NUTRITION

energy source for the colonic epithelium

leptin productionpyy expression

SCFA: butyrate - acetate - propionate

lipid synthesis in the liver gluconeogenesis

energy extraction

energy storageAppetite control

insulin secretion

SCFA also possess immunomodulating and antimicrobial properties and regulate host epigenome

123

5-15% of the total energy required

EPIGENOME REGULATION

INHIBITING HISTONE DEACETYLASE, SCFA CAN MODULATE HOST EPIGENOME

MODULATION OF GENE EXPRESSION IN COLONIC EPITHELIAL CELLS

INTER-INDIVIDUAL PHYLOGENETIC VARIABILITY

THE INDIVIDUAL MICROBIOTA SHOWS AN ASTONISHING LEVEL OF

INTER-INDIVIDUAL VARIABILITY

MICROBIAL FINGERPRINT

• 70% of species phylotypes are subject specific

• no phylotype is present at more than 0.5% of abundance in all subjects

EACH HEALTHY SUBJECT POSSESSES A SPECIFIC AND DYNAMIC SUBSET OF HUNDREDS OF SPECIES

MICROBIOTA PLASTICITY

THE INDIVIDUAL MICROBIOTA COMPOSITION CONTINUOUSLY CHANGES IN RESPONSE TO EXTRINSIC AND

INTRINSIC VARIABLES

DIET

HOST GENETICS

MICROBIOTA MAKE-UP

GIT ENVIRONMENT

(inflammation-disease)

ENV. FACTORS

(env. microbes-geography-climatesanitization-medication)

AGE

DIET SHAPES THE MICROBIOTA AND ITS VAST COLLECTION OF GENES IN A DRAMATIC AND REPRODUCIBLE WAY

•FAST: dietary changes occur and reverse in 1-3 days

•INDIVIDUAL MICROBIOTA SPECIFIC: response to dietary changes is influenced by the initial species composition of the individual microbiota

•SHORT-TERM AND LONG-TERM RESPONDERS: while some bacterial groups respond rapidly to diet, others are modulated exclusively by long-term dietary changes (enterotypes)

HOW MICROBIOTA RESPONDS TO DIET

THE INTESTINAL MICROBIOTA CONFIGURES ITS PHYLOGENET IC PROFILE TO OPTIMIZE ITS CAPACITY TO METABOLIZE DIET ARY

COMPONENTS

MUTUALISM BREAKDOWN

INFLAMMATION AND MICROBIOTAA NON-CONTROLLED PRO-INFLAMMATORY PATHWAY CAN

DRAMATICALLY IMPACT ON THE COMPOSITION OF THE INTESTINAL MICROBIOTA

SUSCEPTIBLE HOST- GENETICS- ENV. FACTORS

CHRONIC GIT INFLAMMATION

MICROBIOTA DYSBIOSIS

RAISE IN PATHOBIONTS

PRO-INFLAMMATORY LOOP

PRO-INFLAMMATORY INTESTINAL MICROBIAL COMMUNITY

DECREASE OF IMMUNO

MODULATORY GROUPS

MANIPULATION OF THE HUMAN INTESTINAL MICROBIOTA

A LIVE MICROBIAL FEED SUPPLEMENT

WHICH BENEFICIALLY AFFECTS THE HOST

PROBIOTICS SHOULD BE ABLE TO SURVIVE AND MULTIPLY IN THE HOST GI TRACT BUT RAPIDLY DISAPPEAR WHEN ORAL ADMINISTRATION IS STOPPED

USE: FUNCTIONAL FOODS (FERMENTED MILKS, INFANT FORMULA, FRUIT DRINKS)

PHARMACEUTICAL PREPARATION (DRIED SUPPLEMENTS)

PROBIOTICS

MOST COMMONLY USED PROBIOTICS

LACTIC ACID BACTERIA

LACTOBACILLUS (L. acidophilus, L. casei,L. delbrueckii,L. gasseri, L. rhamnonsus, L. cellobiosus, L. curvatus, L. fermentum, L. lactis, L. plantarum, L.

reuteri, L. salivarius, L. brevis)

BIFIDOBACTERIUM (B. longum, B. bifidum, B. adolescentis, B. infantis, B. breve, B. animalis, B. lactis )

ENTEROCOCCUS (E. faecalis, E. faecium)

PROBIOTICS OTHER THAN LAB

BACILLUS SPORES (B. cereus, B. clausii, B. subtilis)

SACCHAROMYCES (S. boulardii, S. cerevisiae)

HEALTH PROMOTING EFFECTS OF PROBIOTICS

PROBIOTICS: FROM RESEARCH TO APPLICATION

� Isolation (strain origin)

� Identification/characterization (physiological and genotypic characteriziation)

� Strain screening- Safety: AB-resistance profile

undesidered properties (hemolysis, mucus degradation, production of biogenic amines, etc)

- Efficacy (in vivo functionality, mechanism of action)

- Documentation (safety and efficacy)

� Growth medium

� Fermentation

� Filtration

� Encapsulation (delivery system)

� Drying

� Product formulation

� Packaging functionality

� Supply chain distribution

� Consumer benefit communication

IMPIEGO DEI PROBIOTICIMalattie infiammatorie croniche intestinali

Diarrea da antibiotici

Diarrea del viaggiatore

Colite da C. difficile

Infezione da H. pylori

Disordini funzionali gastrointestinali

Allergie alimentari

Intolleranza al lattosio

Patologie epatiche croniche (steatosi, cirrosi)

Gastroenterite acuta infettiva (Rotavirus)

Coliche gassose

Enterocolite necrotizzante

Faecalibacterium prausnitzii

Roseburia

Bacteroides

NEXT GENERATION PROBIOTICS

‘Non digestible food ingredients that selectively stimulate a limited number of bacteria in the colon, to improve host

health’

PREBIOTICS

• Fructooligosaccharides (tested in humans)• Lactulose (tested in humans) • Trans-galactooligosaccharides

Present in: bananas, artichoke, leeks, onions, garl ic, asparagus, chicory

Application of prebiotics : Beverages and fermented milks, Health drinks, Infant formulae and weaning foods, Cereals, Biscuits, Confectionery, Cakes, Food supplements,

Pet food, Farm animals

PREBIOTICS FERMENTATION IN HUMAN GUT

THANK YOU FOR YOUR ATTENTION

WESTERN DIET

• HIGH FAT• HIGH PROTEIN• HIGH SUGAR• FOOD PROCESSING• FOOD STORING

• LOW FAT• STARCH AND PLANT

POLYSACCHARIDE-RICH• CONTAMINATED• HOMEMADE• PROMPTLY CONSUMED• LOCALLY PRODUCED

MICROBIOTA MAKE-UP

+ Firmicutes+ Proteobacteria

LOW FUNCTIONAL AND PHYLOGENETIC

DIVERSITY

+ Bacteroidetes+ Actinobacteria

HIGH FUNCTIONAL AND PHYLOGENETIC

DIVERSITY

WESTERN DIET RURAL AFRICAN DIET

The continuous immunological cross-talk between the intestinal microbiota and the gut immune system is a vital factor for its

• DEVELOPMENT

• EDUCATION TO TOLERANCE AND RESPONSIVENESS

• FUNCTION/REGULATION

GALT EDUCATION

HUMAN GENOME DOES NOT ENCODE FOR ALL FUNCTIONS REQUIRED FOR IMMUNOLOGICAL DEVELOPMENT BUT

DEPENDS ON THE CRITICAL INTERACTION WITH MICROBIOME

• BIOSYNTHESIS OF NEURO-ACTIVE METABOLITES (lactic acid, propionic acid, 5-hydroxytryptamine)

• REGULATION OF NEUROTRANSMITTER PRODUCTION (GABA, noradrenaline, dopamine, acetylcholine)

• DIRECT NEURONAL ACTIVATION OF STRESS CIRCUITS (modulation of the host inflammatory response)

SYNAPTOGENESIS; PITUITARY-ADRENAL AXIS PROGRAMMING; STRESS REACTIVITY; ANXIETY-

LIKE BEHAVIOR

CENTRAL NERVOUS SYSTEM FUNCTION AND BEHAVIOR