La Chirurgia della Diverticolite Acuta: what’s new

Foligno 22 settembre 2018

Malattia diverticolare e probiotici

Giuseppe Servillo

Patologia Generale

Dip. Medicina Sperimentale

Università degli studi di Perugia

Animals in a bacterial world

Bacteria were one of the first life

forms to appear on Earth, about 3.8

billion years ago, and they will most

likely survive long after humans are

gone.

Bacteria may have played an important

role by assisting in the origins of

multicellular organisms (about 1-2

billion years ago) and in the origins of

animals (about 700 million years ago).

Due to these symbiotic relationships, the very

definitions of an organism, an environment, a

population, and a genome have become blurred

and should be reviewed.

It may be, for instance, that animals are

better viewed as host-microbe

ecosystems than as individuals.

37% of human genes originated in

bacteria

Gut bacteria composition

Nat Rev Microbiol. 2011 Apr;9(4):279-90

Microbial

community

composition

at different

body

locations

in a healthy

human

Many of these homologous genes enable signaling

between animals and bacteria, that include:

influencing normal brain development in mammals

affecting reproductive behavior in both vertebrates

and invertebrates

activating the immune system

mating through olfactory chemicals

Bacteria in an animal’s microbiota communicate

among themselves and exchange signals with the

animal’s organ systems

The Viral Community

The human mycobiome

Nat Immunol. 2013;14:685-90

Localization of dominant bacterial groups

in the intestine

DIET

“Dis-moi ce que tu manges, je te dirai ce que tu es”

“Dimmi cosa mangi e ti dirò chi sei”Jean Anthelme Brillat-Savarin gastronome

Impact of diet in shaping gut microbiotaDe Filippo, PNAS 2010

Maintenance

of Immune

Homeostasis

by

Microbiota-

Derived

Metabolites

Cell Host & Microbe 16, 2014

Microbial Products Induce Mucosal Barrier Functions

Cell Host & Microbe 16, 2014

Life style and diet changes

“Se tu hai una mela e io ho una mela

e ci scambiamo queste mele,

ognuno di noi avrà una mela,

ma se tu hai un’ idea ed io ho un’ idea

e ci scambiamo queste idee,

ognuno di noi avrà due idee”

George Bernard Shaw

Dominant microbes

The human gut microbiota is dominated by five bacterial phyla

Firmicutes contains relevant genera, including Ruminococcus, Clostridium, Lactobacillus

(several strains of which are probiotics), and the butyrate producers Eubacterium,

Faecalibacterium and Roseburia.

Bacteroidetes, Bacteroides, Prevotella and Xylanibacter degrade a variety of complex

glycans, involved in SCFA production.

Actinobacteria, Bifidobacterium (which contains probiotic strains).

Proteobacteria, Escherichia (from the Enterobacteriaceae family) and Desulfovibrio

(which contains sulphate-reducing bacteria).

Verrucomicrobia, Akkermansia (which are specialized for mucus degradation).

Archea

Euryarchaeota contains the prevalent Methanobrevibacter (which is involved in the

continuation of intestinal methanogenesis).