Sept 2011 - Institut de Recherche en Santé Mentale

Table 1. Postmortem Brains. Prefrontal cortex brain tissue (BA44) was obtained in collaboration
with the Quebec Coroner’s Office from the Quebec Suicide Brain Bank (QSBB). All individuals were
male and groups were matched for age, pH and PMI. Psychological autopsies were performed postmortem
for both cases (n=15) and controls (n=15) based on DSM-IV criteria. The control group had
no history of suicidal behaviour or major mood or psychotic disorders.
RESEARCH POSTER PRESENTATION DESIGN © 2011
www.PosterPresentations.com
A. B.
SAT1
2.5
2.5
2.0
2.0
1.5
1.5
1.0
1.0
0.5
0.5
0.0
0.0
Controls
Suicides
Figure 2. Expression of SAT1 and SMOX. Brain expression of SAT1 and SMOX genes(BA44). (A)
SAT1. Group mean ± SEM of AQ values from qRT-PCR (Normalized to GAPDH). SAT1 showed a
significant down-regulation in suicide completers (**P0.05,
Pearsons r = -0.27, R"=0.07).(C) SAT1 vs. miR-34c-5p (p0.05, Pearsons r = -0.11, R"=0.01). (D)
SAT1 vs. miR-320c (p"L,(.)4)*7"C0D9=="8,9K*+(9)>7"C',)+*-=7"M4*N*0":-,-G-"
1234567831520
=>3@0W0=A5X0Y;2;0;XE4;==1520
4;=7?3=0
4;=7?3=0
•!Suicide is a major public health problem. It is estimated that suicide
accounts for 1.8% of the total deaths in the United States [1]. Over
the last decades, a large body of evidence has shown that individuals
who commit suicide have a predisposition that is mediated by
neurobiological factors [2].
•!Changes in the expression of polyamine metabolic enzymes have
been observed in multiple psychiatric conditions, and we have
previously shown the expression of the polyamine genes SAT1 and
SMOX to be down regulated in the brains of suicide completers [3].
•!MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene
expression by means of binding to complementary sequences usually
located in the 3 untranslated region (UTR) of a target gene,
generally leading to mRNA degradation or translational repression [4].
A growing body of evidence supports the role of miRNAs in
neuropsychiatric disorders such as schizophrenia and bipolar disorder
[5].
•!We hypothesize that the down-regulation of the SAT1 and SMOX
genes in suicide completers could be influenced by miRNA posttranscriptional
regulation.!
59:;831)%0 VA/U"W"#/@" VX/#"W"A/X"
EA10 #A/V"W"%/@" V@/@"W"X/V"
9&+,'0!B0 X/U"W"$/$2" X/X"W"$/$U"
Qty Mean (SAT1/GAPDH)
Qty Mean
**
**
8>2616>3;0*,42>#0
SAT1 3’UTR
SMOX 3’UTR
*
Qty Mean (SMOX/GAPDH)
4;=7?3=0
* **
**
Qty Mean (miR-139-5p/RNU6B)
Qty Mean (miR-34c-5p/RNU6B)
Qty Mean (miR-139-5p)
Qty Mean (miR-34c-5p)
Qty Mean (miR-139-5p)
Qty Mean (miR-34c-5p)
**
*
Qty Mean (miR-320c/RNU6B)
Qty Mean (miR-195/RNU6B)
=>3@0
Qty Mean (miR-195)
Qty Mean (miR-320c)
=A5X0
Qty Mean (miR-195)
Qty Mean (miR-320c)
*
**
ID
miRNA Sequence
M#+N*,4N@OPNQ!00 """U["487>8>Y7I0-0I4I40400-I"V["
M#+N*,4NOR/NQ!0 """U["-YY8>Y7YI4-I44-I04I-44I0"V[""
M#+N*,4N@PQ0 """U["4>Y8>Y8>0-I---4-44II0"V["
M#+N*,4NOTU/0 """U["->>>Y87YII44I-I-III4"V["
microRNA
Polyamine Genes
SAT1
miR-139-5p
SMOX
miR-195
OAZ1
miR-34c-5p
OAZ2
miR-320c
AMD1
ARG2
SMS
8528?7=152=0
1. We found a significant up-regulation of miRNAs
predicted to target the 3UTR of SAT1 and SMOX in the
brains of suicide completers compared to controls.
2. We demonstrated a significant negative correlation in
expression between SAT1, miR-320c and miR-34c-5p, and
between SMOX, miR-320c and miR-139-5p.
3. Our results suggest a relationship between these 4
miRNAs and the polyamine genes SAT1 and SMOX in suicide
behavior and we postulate that the down-regulation of
SAT1 and SMOX is post-transcriptionally regulated by miRNA
activity.
4;Z;4;28;=0
>8I25[?;6YA;23=0
miR-124a
miR-497
miR-873
miR-139-5p
miR-195
miR-34a
miR-198
miR-34c-5p
miR-320c
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