Digestive and Liver Disease - Volume 48 - Supplement 2 - February 2016

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e104 Abstracts of the 22nd National Congress of Digestive Diseases / Digestive and Liver Disease 48S2 (2016) e67–e231
to the tumors from control mice. Surprisingly, and contrary to our
expectations, tumors from EMILIN2 KO mice did not display any
changes in the activation of the Wnt/ b-catenin pathway compared
to the controls. Accordingly, the b-catenin target genes cyclin D1 and
c-Myc were not altered in the tumors and in the normal mucosa of
the two mouse models. Histopathological and IHC analyses indicated
that the tumors from EMILIN2 KO mice where characterized by a
higher number of macrophages and granulocytes than those from
WT mice. Similar alterations in the KO model were found during
the acute fase of inflammation: mice subjected to DSS treatment
alone developed a more severe colitis than WT mice. Accordingly,
the infiltration of myeloid cells within the intestinal mucosa was
altered and the serum level of a number of cytokines, including IL-
1b, INF-gamma, TNF-a and IL-10, was affected.
Conclusions: Our results let us suggest that EMILIN2may affect colon
carcinogesis impinging on the recruitment and/or the activation
of myeloid cells. By altering the inflammatory microenvironment,
EMILIN2 may significantly influence colon cancer development.
OC.09.3
PALMITOYLETHANOLAMIDE (PEA) REDUCES COLITIS-INDUCED
ANGIOGENESIS THROUGH AKT/MTOR PATHWAY INHIBITION
D’Alessandro A.*2, Pesce M.2, Esposito G. 1, Iuvone T.2, Affinito G.2,
De Palma G.D.2 , Cuomo R.2, Sarnelli G.2
1La Sapienza University, Rome, Italy, 2Federico II University, Naples,
Italy
Background and aim: In a recent study, we have demonstrated
that PEA improves intestinal inflammation in a mouse model of
ulcerative colitis. Neovascularization, via the activation of the Akt/
mTOR pathway, appears to be crucial in the maintenance of the
inflammatory response and might be targeted when developing new
treatment strategies in IBD. Given its anti-angiogenic properties, we
aimed to evaluate whether PEA affects angiogenesis in mice with
DSS-induced colitis.
Material andmethods: Six-weeks-oldwild-typemicewere randomly
divided into non-colitic group; colitic group; colitic group receiving
PEA (10 mg/kg); colitic group receiving PEA and selective PPAR-a or
PPAR-g antagonists. Colitis was induced by administrating 4% DSS
in drinking water for 6 consecutive days; PEA alone, or combined
with PPAR antagonists, was intraperitoneally administered from
day 2 to 6. All animals were sacrificed at day 7. Hemoglobin content
measurement and immunohistochemistry for CD31 were performed
to evaluate neovascularization. VEGF release was estimated by ELISA,
while the expression of VEGF receptor and the activation of the Akt/
mTOR pathway were evaluated by western blot analysis.
Results: The hemoglobin content and the expression of CD31 were
significantly increased in mice with DSS-induced colitis compared
to controls (+390 and +371%; all p<0.001), while a reduction was
observed in PEA treated-mice (-60 and -47%; all p<0.05). A significant
increase of VEGF release and VEGFR expression was detected in
colitis mice (+600 and + 247%; all p<0.001). Interestingly, PEA
administration significantly reduced both VEGF release and VEGFR
expression (-72 and -66%; all p<0.01) in colitis model. We detected a
significant higher expression of phosphor-Akt,- mTOR and -p70SK in
mice with DSS-colitis (+850, +1600 and +1400%; all p<0.001); whilst
PEA reduced the phosphorylation of all these factors (-76.5, -68 and
-71%; all p<0.01). PPAR-a antagonist, but not PPAR-g antagonist,
reverted all effects of PEA.
Conclusions: We demonstrated that PEA is able to reduce
angiogenesis in a mouse model of colitis. Moreover, we showed that
antiangiogenic effect of PEA depends on the specific inhibition of
the AkT/mTOR axis, through the activation of PPAR-a pathway. Due
to its anti-inflammatory and anti-angiogenic characteristics, PEA
represents an interesting candidate for future clinical studies in IBD.
OC.09.4
EXPRESSION OF THE ACTIVATED FORM OF AMPK IS REDUCED
IN IBD BUT SELECTIVE ACTIVATION OF THIS KINASE IS NOT
SUFFICIENT TO REVERT INTESTINAL INFLAMMATION
Di Fusco D.*, Monteleone I., Marafini I., Dinallo V., Laudisi F.,
Pallone F., Monteleone G.
Department of Systems Medicine, University of Rome “Tor Vergata”,
Rome, Italy
Background and aim: AMP-activated protein kinase (AMPK) is
an energy cellular sensor involved in many biological functions,
including autophagy, apoptosis and immune cell functions. In mice
with dextran sulfate sodium (DSS)-colitis, expression of the active
form of AMPK is reduced and treatment with metformin, a known
activator of AMPK, promotes resolution of the ongoing colitis.
Aim: To evaluate whether the expression of active AMPK is
deregulated in inflammatory bowel disease (IBD) and activation of
AMPK is sufficient to revert colitis in mice.
Material and methods: Expression of phosphorylated (active) form
of AMPK was evaluated in inflamed biopsy samples of patients with
ulcerative colitis (UC), patients with Crohn’s disease (CD) and normal
controls (CTR) by western blotting and immunhistochemistry. IBD
lamina propria mononuclear cells (LPMC) were activated with toll-
like receptor ligands in the presence or absence of metformin or
A-769662, a specific and selective activator of AMPK. After 24 hours,
inflammatory cytokines were evaluated by real-time PCR. To assess
the in vivo effect of AMPK activation on the ongoing colitis, DSS-
treated mice were given intra-peritoneally metformin or A-769662
after induction of colitis.
Results: Expression of phosphorylated AMPK was reduced in
UC samples as compared to CD and controls, and such a decrease
was evident in both epithelial and lamina propria compartments.
Treatment of IBD LPMC with CpG or poli I:C increased TNF RNA
transcripts and this effect was reversed by both metformin and
A-769662. Induction of DSS-colitis in mice was accompanied by
diminished phosphorylation of AMPK. Mice treated with A-769662
exhibited increased expression of active AMPK in the colons but no
resolution of colitis. In contrast, metformin-treated mice showed
enhanced phosphorylation of AMPK concomitant with attenuation
of colitis.
Conclusions: Expression of active AMPK is decreased in patients
with UC and in mice with experimental colitis. Selective activation
of AMPK is not sufficient to dampen the ongoing colitis. Data
suggest that metformin-mediated resolution of colitis relies on the
activation of additional pathways other than AMPK.
OC.09.5
GENERATION AND FUNCTIONAL CHARACTERIZATION OF HUMAN
INKT CELL LINES AND CLONES FROM HEALTHY AND INFLAMED
INTESTINE
Burrello C.1, Pellegrino G.* 2, Nizzoli G.2, Colombo F.3, Botti F.4,
Conte D.5, Caprioli F.2, Rescigno M.1, Facciotti F. 1
1 Department of Experimental Oncology, European Institute of
Oncology, Milano, Italy, 2Dipartimento di Fisiopatologia Medico-
Chirurgica e dei Trapianti, Università degli Studi di Milano, Milano,
Italy, 3Clinical Chemistry and Microbiology Laboratory, Flow Cytometry
and Experimental Hepatology Service, Fondazione IRCCS Ca’ Granda
Ospedale Maggiore Policlinico, Milano, Italy, 4General and Emergency
Surgery Unit, Fondazione IRCCS Cà Granda, Ospedale Maggiore
Policlinico, Milano, Italy, 5Gastroenterology and Endoscopy Unit,
Fondazione IRCCS Cà Granda, Ospedale Maggiore Policlinico, Milano,
Italy
Backgroundandaim: Invariant natural killer T (iNKT) cells constitute
a population of lipid-specific T lymphocytes with multiple functions