Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like receptor pathways in coronary artery disease patients

Abstract

Background and aims:
In coronary artery disease (CAD) epicardial adipose tissue (EAT) shows an elevated inflammatory infiltrate. Toll-like receptors (TLRs) are important mediators of adipose tissue inflammation and they are able to recognize endogenous products released by damaged cells. Because adipocyte death may be driven by hypertrophy, our aim was to investigate in CAD and non-CAD patients the association between EAT adipocyte size, macrophage infiltration/polarization and TLR-2 and TLR-4 expression.

Methods and results:
EAT biopsies were collected from CAD and non-CAD patients. The adipocyte size was determined by morphometric analysis. Microarray technology was used for gene expression analysis; macrophage phenotype and TLRs expression were analyzed by immunofluorescence and immunohistochemical techniques. Inflammatory mediator levels were determined by immunoassays. EAT adipocytes were larger in CAD than non-CAD patients and do not express perilipin A, a marker of lipid droplet integrity. In CAD, EAT is more infiltrated by CD68-positive cells which are polarized toward an M1 state (CD11c positive) and presents an increased pro-inflammatory profile. Both TLR-2 and TLR-4 expression is higher in EAT from CAD and observed on all the CD68-positive cells.

Conclusions:
Our findings suggested that EAT hypertrophy in CAD promotes adipocyte degeneration and drives local inflammation through increased infiltration of macrophages which are mainly polarized towards an M1 state and express both TLR-2 and TLR-4.

Full text

Epicardial adipocyte hypertrophy: Association with M1-polarization
and toll-like receptor pathways in coronary artery disease patients
E. Vianello
a,
*
,1
, E. Dozio
a,1
, F. Arnaboldi
a
, M.G. Marazzi
a
, C. Martinelli
a
, J. Lamont
b
,
L. Tacchini
a
, A. Sigrüner
c
, G. Schmitz
c
, M.M. Corsi Romanelli
a,d
a
Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
b
Randox Laboratories LTD, R&D, Crumlin-Antrim, Belfast, Northern Ireland, UK
c
Institute for Clinical Chemistry and Laboratory Medicine, University of Regensburg, Germany
d
SMEL-1 Clinical Pathology, I.R.C.C.S. Policlinico San Donato, Milan, Italy
Received 18 March 2015; received in revised form 2 November 2015; accepted 7 December 2015
Available online ---
KEYWORDS
Epicardial adipose
tissue (EAT);
Coronary artery
disease (CAD);
Macrophages
infiltration;
Toll-like receptors
(TLRs)
Abstract Background and aims: In coronary artery disease (CAD) epicardial adipose tissue (EAT)
shows an elevated inflammatory infiltrate. Toll-like receptors (TLRs) are important mediators of
adipose tissu e inflammation and they are able to recognize endogenous products released by
damaged cells. Because adipocyte death may be driven by hypertrophy, our aim was to investi-
gate in CAD and non-CAD patients the association between EAT adipocyte size, macrophage infil-
tration/polarization and TLR-2 and TLR-4 expression.
Methods and results: EAT biopsies were collected from CAD and non-CAD patients. The adipocyte
size was determined by morphometric analysis. Microarray technology was used for gene
expression analysis; macrophage phenotype and TLRs expression were analyzed by immunoflu-
orescence and immunohistochemical techniques. Inflammatory mediator levels were deter-
mined by immunoassays.
EAT adipocytes were larger in CAD than non-CAD patients and do not express perilipin A, a
marke r of lipid droplet integrity. In CAD, EAT is more in filtrated by CD68-posit ive cells which
are polarized toward an M1 state (CD11c positive) and presents an increased pro-
inflammatory profile. Both TLR-2 and TLR-4 expression is higher in EAT from CAD and observed
on all the CD68-positive cells.
Conclusions: Our findings suggested that EAT hypertrophy in CAD promotes adipocyte degener-
ation and drives local inflammation through increased infiltration of macrophages which are
mainly polarized towards an M1 state and express both TLR-2 and TLR-4.
ª 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the
Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Feder-
ico II University. Published by Elsevier B.V. All rights reserved.
Introduction
Coronary artery disease (CAD) is a clinical condition
characterized by stenosis of coronary vessels due to
atherosclerotic plaque formation. Recently, CAD onset and
progression has been related to epicardial adipose tissue
(EAT), a visceral fat depot surrounding the heart and
sharing with myocardium the same microcirculation [1].
* Corresponding author. Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Luigi Mangiagalli 31, 20133 Milan,
Italy. Tel.: þ39 02 50315342; fax: þ39 02 50315338.
E-mail address: elena.vianello@unimi.it (E. Vianello).
1
These author equally contribute in this article.
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005
http://dx.doi.org/10.1016/j.numecd.2015.12.005
0939-4753/ª 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of
Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.
Nutrition, Metabolism & Cardiovascular Diseases (2016) xx,1e8
Available online at www.sciencedirect.com
Nutrition, Metabolism & Cardiovascular Diseases
journal homepage: www.elsevier.com/locate/nmcd

With increasing thickness, EAT is able to locally produce
reactive oxygen species, cytokines and chemokines which
may create a local toxic and pro-inflammatory environ-
ment [2e5]. In particular, visceral obese patients display
an increased EAT thickness and the tissue is mostly infil-
trated by macrophages which may amplify the local pro-
inflammatory response by producing itself additional
mediators [6,7].
Immunohistochemical identification of macrophages is
usually performed with antibody against CD68 antigen.
These cells may be further characterized according to their
polarization state as pro-inflammatory CD11c-positive
macrophages, known as M1 [8,9], and anti-inflammatory
CD206-positive macrophages, known as M2 [10]. The po-
larization process depends on different local stimuli
[11,12].
Recently, the presence of stressed or dying adipocytes,
releasing different cellular components, like residual lipid
droplets, has been suggested as an additional stimulus
inducing macrophage infiltration and M1 polarization,
probably through the activation of toll-like receptors
(TLRs) which play a primary role in the innate immune
response [13,14]. Although TLRs are mainly known for
their ability to recognize different pathogen-associated
molecular patterns, recently it has been shown that they
can also recognize endogenous molecules, such as heat
shock proteins or cell debris [15], called damage-
associated molecular patterns (DAMPs) [16].
In the field of CAD, recent studies suggested that
macrophage EAT infiltration is also one of the main causes
of the chronic inflammatory state associated with the
disease [17,18]. Moreover, it has been reported that TLR-2
and TLR-4 are the main TLR isoforms involved in athero-
sclerosis and their expression is up-regulated in circulating
monocytes [19e21].
Currently, less is known about the mechanisms pro-
moting macrophage polarization in EAT in CAD patients. In
the present study our aim was to investigate in CAD and
non-CAD patients the association between EAT adipocyte
size, macrophage infiltration/polarization and TLR-2 and
TLR-4 expression.
Methods
Study population
Fifty male patients (30 CAD, undergoing coronary artery
bypass grafting surgery, and 20 non-CAD, referring to
hospital for valvular replacement surgery), aged 18e65
years, were enrolled at I.R.C.C.S. Policlinico San Donato.
Exclusion criteria were: impaired left ventricular ejection
fraction, congestive heart failure, acute myocardial infarc-
tion (<6 month), presence of pace-maker, type-1 diabetes
mellitus, neoplasm, prior major abdominal surgery, renal/
liver diseases and unstable (>5% change) body weight in
the least 6 months. CAD and non-CAD patients had similar
body mass index (BMI, kg/m
2
) (26.52  2.59 vs.
27. 11  4.17) and AST (U/L) (31.36  31 .12 vs.
30.44  42.50). ALT (U/L) (38.30  31.42 vs. 17.33  7.39),
LDL-cholesterol (mg/dL) (85.00  33.54 vs. 110.82  37.05)
and triglycerides (mg/dL) (130.10  64.80 vs.
139.80  71.27) were increased in CAD patients (p < 0.05).
HDL cholesterol was reduced (36.51  10.41 vs.
48.00  11.13; p < 0.05). The study protocol was approved
by the local Ethics Committee (ASL Milano Due, protocol
number 2516) and patients gave their written informed
consent, conducted in accordance with the Declaration of
Helsinki, as revised in 2013.
EAT and blood collection
EAT biopsy samples were harvested adjacent to the prox-
imal right coronary artery prior to initiation of cardiopul-
monary bypass pumping. For gene expression analysis,
samples were stored in Allprotect Tissue Reagent (Qiagen,
Hilden, Germany). For histological assays, tissues were
fixed in 4% paraformaldehyde. EDTA plasma samples were
collected and stored at 20

C until analysis.
Adipocyte size quantification
Three mm
3
EAT biopsies were fixed in 4% para-
formaldehyde for 16 h at 4

C, dehydrated in graded scale
of ethanols and paraffin embedded. Sections of 4 mm were
obtained using rotary microtome (RM2245, Leica Micro-
systems GmbH, Wetzlar, Germany) and stained with
hematoxylin-eosin (SigmaeAldrich, Milan, Italy). The
adipocyte size was evaluated on 10 images acquired
using Nikon Eclipse 80i microscope equipped with digital
camera Nikon DS-5Mc (Nikon, Tokyo, Japan) and image
acquisition software (ACT-2U). Diameter and area of adi-
pocytes were measured using image processing software
(Image Pro Plus version 4.5.019; USA Media Cybernetics
Inc; Maryland, USA).
Immunohistochemical staining
Deparaffinized EAT sections were rehydrated and antigen
retrieval was performed by autoclaving in sodium citrate
buffer (0.01 M, pH 6) for 5 min at 120

C. After quenching
of endogenous peroxidases (0.3% H
2
O
2
for 20 min), and
blocking with swine serum (Dako Cytomation), sections
were incubated with anti-human primary anti-
bodies:mouse monoclonal CD68 (1:100, 1 h) (Biocare
Medical, Concord, CA), mouse monoclonal CD11c (1:200,
over night, (on)) (Proteintech, Manchester, UK), mouse
monoclonal CD206 (1:20, on) (R&D Systems, Minneapolis,
MN, USA), rabbit polyclonal PLIN1 (1:200, on) (LifeSpan
Bioscience, Albuquerque, NM, USA), polyclonal rabbit TLR-
2 (1:400, Bio-Rad, Milan, Italy) and polyclonal rabbit TLR-4
(1:20,0 LifeSpan BioSciences). Amplification of immune
signal was performed using anti-mouse and anti-rabbit
HRP-polymer complex (MACH 1 Universal HRP-Polymer
detection, Biocare Medical). Betazoid DAB (Biocare
2 E. Vianello et al.
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

Medical) was used for color development. Sections were
counterstained with Mayer’s hematoxylin and mounted
with Mowiol 4e88 (Calbiochem, La Jolla, CA, USA). Nega-
tive controls were performed by replacing primary anti-
bodies with PBS. Immunohistochemical reactions were
observed and acquired with Nikon Eclipse 80i microscope.
For the semi-quantitative evaluation of IHC staining of
CD68, CD11c, CD206, TLR-2 and TLR-4, slides were
reviewed and scored by a double-blind analysis performed
by two independent scientists. We adopted the German
semi-quantitative scoring system, slightly modified for our
purpose, in considering the staining intensity and area
extent, which has been largely accepted and used in pre-
vious studies [22]. The intensity of the staining was
quantified using the following scores: 0 Z negative,
1 Z weakly positive, 2 Z moderately positive,
3 Z strongly positive. The extent of the staining was
quantified by evaluating the percentage of the positive
staining areas in relation to the whole areas of the section,
where a score of 0 was given for 0e1% reactivity, 1 point
was assigned for 1e10% reactivity, 2 points were assigned
for 11e25% reactivity, 3 points were given for 26e50%
reactivity, 4 points were given for 51e80% reactivity, and
samples with >80% reactivity were assigned a total of 5
points. Since macrophages are localized in the spaces be-
tween adipocytes, we could just evaluate a maximum of 3
points for the extent of the staining. The final immuno-
reactive score was determined by multiplying the intensity
score by the extent score with the minimum score
attainable being 0 and a maximum score of 9. The 9-tier
scoring was also simplified by combining scores 8e9:
strong expression (þþþ), 6e7: intermediate expression
(þþ), 2e5: weak expression (þ), and 0e1: negative NRIP
expression ().
Double-immunofluorescence staining
Deparaffinized and rehydrated sections were blocked with
swine serum (Dako Cytomation, Milan, Italy) for 30 min at
room temperature (RT) and incubated on with polyclonal
rabbit TLR-4 (1:200) or with polyclonal rabbit TLR-2 anti-
bodies (1:400) and then with secondary TRITC-conjugated
donkey anti-rabbit IgG (R&D Systems) for 1 h at RT. Sec-
tions were secondly incubated with monoclonal mouse
CD68 (1:100, 2 h), and then with FITC-conjugated donkey
anti-mouse IgG (1:20 0, R&D Systems, 1 h). After 5 min of
DAPI incubation (AbDSerotec, Puchheim, Germany), sec-
tions were mounted with Mowiol 4-88. Negative controls
were performed by replacing primary antibodies with PBS.
Images were acquired with fluorescence microscope
(Nikon Eclipse 80i).
RNA extraction and gene expression analysis of EAT
Total RNA was extracted from tissue with the RNeasy Lipid
Tissue Kit (Qiagen). RNA concentration was quantified by
NanoDrop 2000 (ThermoScientific, Wilmington, Germany)
and RNA integrity was assessed using the Agilent RNA
6000 Nano kit and the Agilent 2100 Bioanalyzer (Agilent
Technologies, Santa Clara, CA). Gene expression analysis
was performed by one color microarray platform (Agilent).
Hybridization was performed using Agilent Gene Expres-
sion hybridization Kit and scanning with Agilent G2565CA
Microarray Scanner System. Data were processed using
Agilent Feature Extraction Software (10.7) with the single
color gene expression protocol and raw data were
analyzed with ChipInspector Software (Genomatix,
Munich, Germany).
Statistical analysis
Data were expressed as mean  standard deviation (SD)
and analyzed by GraphPad Prism 5.0 program (GraphPad
Software, Inc., San Diego, CA). The normality of data dis-
tribution was assessed by the KolmogroveSmirnoff test.
Comparison between groups was performed using Stu-
dent’s two-tailed unpaired T-test or ManneWhitney U-
test, as appropriate. A p value < 0.05 was considered sta-
tistically significant.
Results
EAT adipocytes are hypertrophic in CAD
Morphometric analysis of EAT adipocytes suggested that
CAD patients (Fig. 1a) have bigger adipocytes than non-
CAD (Fig. 1c). In CAD, EAT adipocytes displayed both
longer diameter (Fig. 1b) and larger area (Fig. 1d) than non-
CAD (diameter: 81.92  17.19 mm vs. 61.81  5.83 mm; area:
257.10  56.45 mm
2
vs. 191.40  18.82 mm
2
; p < 0.05 for
both).
Perilipin A immunoreactivity is absent in EAT from CAD
Perilipin A, a lipid droplet protein involved in lipid traf-
ficking, has been used as a marker of degenerative lipid
droplets and cell death. In CAD, no perilipin A immuno-
reactivity was observed in EAT (Fig. 2a). Contrarily, a
positive immunoreactivity was observed in non-CAD
(Fig. 2b). Perilipin A mRNA was also reduced in CAD (fold
change:  1.53, p < 0.01) ( Fig. 2c).
EAT infiltrating macrophages are M1-polarized in CAD
Immunohistochemical analysis revealed that CD68-
positive cells were prevalent in CAD and appear as ag-
gregates. Only scattered CD68-stained cells were present
in non-CAD (Fig. 3a and b).
Regarding macrophage polarization, CD11c-positive
cells were mostly observed in CAD (Fig. 3c and d),
whereas few CD206-positive macrophages appeared
mainly in non-CAD (Fig. 3e and f). Semi-quantitative
analysis performed with German scoring system
confirmed that, in CAD, macrophages are shifted toward
Epicardial adipocyte hypertrophy 3
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

Figure 1 Morphometric analysis of adipocyte sizes in CAD and non-CAD EAT samples. Hematoxylin-eosin staining of CAD (a) and non-CAD (c) EAT
sections. Bars: 60 mm. Quantification of adipocyte diameter (b) and area (d) in CAD and non-CAD patients. Shown are mean values  SD. *p < 0.05.
Figure 2 Perilipin A expression in EAT. Perilipin A immunoreactivity is absent in CAD (a), whereas it is present in non-CAD (b). Bars: 10 mm.
Reduced mRNA level of perilipin A was observed in CAD (c). **p < 0.01.
4 E. Vianello et al.
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

an M1 pro-inflammatory state (Fig. 3). At gene level we did
not find any statistically significant difference in CD68,
CD11c and CD206 levels between CAD and non-CAD (data
not shown).
EAT infiltrating macrophages in CAD are immunoreactive
for both TLR-2 and TLR-4
IHC analysis indicated an increased immunoreactivity for
both TLR-2 and -4 in CAD (Fig. 3gel) in stromal region. Due
to their role in promoting inflammatory pathways in
response to DAMPs, we then evaluated whether EAT
infiltrating CD68-positive macrophages, usually localized
in these stromal regions, were immunoreactive for TLR-2
and TRL-4. In CAD, we observed that all CD68-positive
cells were also immunoreactive for both TLR-2 (Fig. 4aec)
and -4 (Fig. 4gei). In non-CAD patients, TLR-2 was almost
undetectable (Fig. 4def), whereas TLR-4 was faintly
expressed (Fig. 4len).
CAD patients displayed increased level of pro-
inflammatory mediators in EAT
The pro-inflammatory mediators MCP-1, TNF-a, PTX3, TLR-
2 and -4, which are involved in the innate immunity
response, as well as the anti-inflammatory cytokine adi-
ponectin were evaluated in EAT. CAD patients displayed
about 2-fold increase in MCP-1 and TNF-a levels (p < 0.05),
a 1.6-fold increase in TLR-2 (p < 0.01) and 1.3 fold increase
in TLR-4 (p < 0.05). A 4-fold increase in PTX3 level has also
been observed (p < 0.05). Contrarily, adiponectin level was
1.7-fold decreased in CAD (p < 0.001) (Fig. 5).
Discussion
The novelty of our study is the observation that the
increased inflammatory state observed in EAT in CAD
seems to be induced by hypertrophic and damaged adi-
pocytes and TLR-2 and TLR-4 up-regulation may represent
one potential molecular link between adipocyte death and
the activation of the immune response.
Previous studies suggested that the increased macro-
phage infiltration in obese visceral as well as subcutane-
ous adipose tissue may be promoted by stressed and/or
dying adipocytes which release different cellular compo-
nents, such as residual lipid droplets. Moreover, it has
been found an association between macrophage infiltra-
tion and increased adipocyte dimension [13]. To our
knowledge, our study is the first one exploring such
relationship in EAT in CAD. We observed that in CAD, EAT
adipocytes are hypertrophic compared to non-CAD and
the loss of perilipin A immunoreactivity should suggest
the lipid droplet degeneration. Perilipin A is a lipid-
droplet associated protein involved in the regulation of
adipocyte lipolysis [23]. Previous data indicated that the
deletion of perilipin A results in leanness and reverses
obesity in db/db mouse [24]. According to these data and
our morphometric results, we expected to observe an
increased perilipin A expression in CAD patients, as a
Figure 3 Immunohistochemical and semi-quantitative analysis of
macrophage phenotype and TLR-2 and TLR-4 expression in EAT. Panels
a and b show CD68-positive cells, c and d CD11c-positive cells, e and f
CD206 positive cells. C, d, e and f inserts are enlargements of macro-
phage staining. Panels g and h show TLR-2 positive cells; i and l show
TLR-4 positive cells. Bars: aee, 30 mm; fel, 60 mm; inserts: a, 10 mm; c, d,
e and f, 5 mm (a). The table shows the semi-quantitative analysis per-
formed by German scoring of antigen presented in the figures. CD6 8,
CD11c, TLR-2 and TLR-4 were most expressed in CAD (9-tier scoring for
all antigens) than non-CAD patients. Contrarily, CD206 was lower in
CAD than non-CAD (3-tier vs. 6-tier).
Epicardial adipocyte hypertrophy 5
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

potential mechanism promoting adipocyte hypertrophy.
On the contrary, we observed an overall reduction in its
level. In addition to its role in the regulation of lipolysis,
the protein has also been acknowledged as a marker of
lipid droplet integrity and its down expression/depletion
is a sign of lipid droplet degeneration [13]. One potential
explanation of EAT adipocyte death in CAD may be their
increased size. In fact, it is known that adipocyte hyper-
trophy associated to deregulated cellular metabolism
might promote adipocyte death [7,25]. Moreover, the
hypertrophic state observed may be a peculiarity of CAD
pathology regardless of the anthropometric characteris-
tics of the patients. In fact, our study showed that EAT
adipocytes resulted bigger in CAD than non-CAD despite
the two groups were matched for BMI. Thus, the yet
known inflammatory state previously described in EAT in
CAD could be explained by our observation of a link
between EAT hypertrophy and adipocyte death and the
presence of macrophages polarizated toward a pro-
inflammatory M1 state.
The novelty of our study is also the observation that
macrophages infiltrating EAT express both TLR-2 and -4
which are the main players in the innate immune
response. In fact, the activation of these receptors by
endogenous products released by perilipin A-negative
adipocytes may lead to NF-kB translocation [26] and up-
regulation of pro-inflammatory mediators [26,27].
Since EAT and pericoronary fat amount have been
related to the presence and extent of coronary artery
plaques, coronary artery calcification and production of
inflammatory mediators [28e30], future correlations be-
tween EAT adipocyte size, CAD severity and inflammation
represent an interesting point to be addressed in future
studies.
Figure 4 Double immunofluorescence staining of CD68-positive cells with anti-TLR-2 and -4 antibodies. Panels a, d, g and l show CD68 staining.
Panels b and e represent TLR-2 and panels h and m TLR-4 staining. Panels c, f, i and n represent double staining showing the colocalization of CD68
with TLRs. Bar: 10 mm.
6 E. Vianello et al.
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

In conclusion, our findings suggested that EAT hyper-
trophy in CAD promotes adipocyte degeneration and
drives local inflammation through increased infiltration of
macrophages which are mainly polarized towards an M1
state and express both TLR-2 and TLR-4.
Acknowledgements
The authors thank: Dr. L. Menicanti, I.R.C.C.S. Policlinico
San Donato, for patient enrollment and EAT isolation; Dr. T.
Konovalova University of Regensburg, for bioinformatic
support; Ms. Judy Bagott for editing the manuscript. This
work was supported by funds from the Italian Ministry for
Health “Ricerca Corrente” IRCCS Policlinico San Donato
(number: 9.11.1) and internal funds from Eu Framework 7
project Lipidomic Net (number 202272) of University of
Regensburg.
Appendix A. Supplementary material
Supplementary data related to this article can be found at
http://dx.doi.org/10.1016/j.numecd.2015.12.005.
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Figure 5 EAT expression of inflammation-related molecules in CAD and non-CAD. Gene expression analysis of mediators involved in inflammation
in EAT was performed with Agilent system. Shown are mean values  SD. *p < 0.05, **p < 0.01 and ***p < 0.001.
Epicardial adipocyte hypertrophy 7
Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005

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Please cite this article in press as: Vianello E, et al., Epicardial adipocyte hypertrophy: Association with M1-polarization and toll-like
receptor pathways in coronary artery disease patients, Nutrition, Metabolism & Cardiovascular Diseases (2016), http://dx.doi.org/
10.1016/j.numecd.2015.12.005