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.
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
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
“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).