CAN EMERGING GENOMIC DATA BE LEVERAGED …•HSD17B13 rs72613567:TA is a common splice variant (AF...
Transcript of CAN EMERGING GENOMIC DATA BE LEVERAGED …•HSD17B13 rs72613567:TA is a common splice variant (AF...
CAN EMERGING GENOMIC DATA BE LEVERAGED FOR NASH THERAPEUTICS
Arun J. Sanyal MBBS, MDZ Reno Vlahcevic Professor of Medicine, Physiology and Molecular Pathology
Virginia Commonwealth University School of Medicine
Richmond, VA
+ =
Conflicts of Interest
• Dr. Sanyal is President of Sanyal Biotechnologies
• Stock options for Genfit, Tiziana, Indalo, Durect, Exhalenz, Galmed
• Consultant- Gilead, Intercept*, Allergan*, Lilly, Novo Nordisk, Astra Zeneca-Medimmune*, Novartis, Pfizer, Genentech*, Merck, Bristol Myers*, Boehringer Ingelhiem*, Immuron*, Echosense, GE, OWL*, Birdrock, Tern, Sundise, RedX*, IFMO, Lipocine*, Innovate*, Zydus*, AMRA, Hemoshear,
• Grant support: Bristol Myers, Intercept, Gilead, Allergan, Merck, Echosense, Novartis, Boehringer Ingelhiem
* no financial remuneration in last 24 months
Genetics influences the development and progression of NASH
Biochimica et Biophysica Acta 1812 (2011) 1557–1566
PNPLA3 is associated with steatohepatitis
Sookoian and Pirola, Hepatology 2011 Jun;53(6):1883-94.
The impact of genetic risk variants on liver damage is proportional to that on hepatic fat accumulation
Standardized coefficients are adjusted for age,
sex, BMI, enrolment criteria or ethnicity
Linear relationship between liver steatosis and fibrosis
PNPLA3
TM6SF2
GCKR
MBOAT7
VARIANT
Dongiovanni, Mancina, Stender J Int Med 2017
• HSD17B13 rs72613567:TA is a common splice variant (AF ~26%).
• The rs72613567:TA variant is associated with:
• Decreased Liver Transaminases
• Reduced risk of alcoholic and non-alcoholic liver disease and cirrhosis.
• Protection from NASH in individuals with fatty liver.
N. S. Abul-Husn et al. NEJM 2018; 378(12)
HSD17B13: A Novel Genomics-Driven Drug Target
HSD17B13
SERPINA1
TM6SF2
PNPLA3
SAMM50
GPT
ERLIN1
PNPLA3
SERPINA1GOT1
HSD17B13
SAMM50
SLC39A12
Alanine aminotransferase Aspartate aminotransferase
Silencing PNPLA3 reduces lipid accumulation
Linden et al, Mol Metab. 2019 Apr; 22: 49–61.
So how does PNPLA3 cause steatohepatitis?
Study design for overexpression of PNPLA3 wildtype (WT) or PNPLA3 I148M in DIAMOND Model
Chow diet
Western diet
Chow diet
Western diet
Chow diet
Western diet
8 weeks on diet
Endpoints measured:• Weight, Insulin resistance, markers of liver injury• Gross appearance of liver• Histology: H&E, Sirius red• Assessment of pathways known to be relevant in human NASH:
• Lipid metabolism (FAS, ACC); Oxidative stress (nrf2); ER stress (eif2a, CHOP, GRP78); Apoptosis (C3, PARP cleavage); Inflammation (JNK, NFkB, p38 MAPkinase, ERK); Fibrosis (Collagen 1 and III, MMP13)
Confirmation of liver-specific PNPLA3 expression
Mouse
GAPDH
Human
PNPLA3
PNPLA3 protein expression in liver
Liver-specific human PNPLA3 expression
I148M mutant PNPLA3 induced hepatomegaly but did not worsen insulin resistance
0.00
0.02
0.04
0.06
CDNW
AAV luc WT
pnpla3
MT
pnpla3
AAV luc WT
pnpla3
MT
pnpla3
WDSW
Liv
er/
bod
y w
eigh
t ra
tio (
g)
*
*
Blo
od
glu
cose
(m
g/d
l)
Time (min)
0 15 30 45 60 75 90 105 1200
50
100
150
Insulin-tolerance test
Mutant PNPLA3 increased steatohepatitc activityC
DN
WW
DS
W
AAV luc PNPLA3 WT PNPLA3 I148MA Figure 2
0
1
2
3
His
tolo
gic
al sco
re
CDNW WDSW
B
0.0
0.5
1.0
Steatosis
CDNW WDSW
C
0
1
2
CDNW WDSW
#D
0
1
2
3
4
5
6
CDNW WDSW
##E
AAV lucPNPLA3 WT
PNPLA3 I148M
Hepatocellular ballooning score
Lobular inflammation
NAFLDActivity score
0
25
50
75
100
Normal
NAFL
NASH
CDNW
AAV luc WT
pnpla3
MT
pnpla3
AAV luc WT
pnpla3
MT
pnpla3
WDSW
Mutant PNPLA3 accelerated fibrosis
AAV lucPNPLA3 WT
PNPLA3 I148M
CD
NW
WD
SW
0.0
0.5
1.0
1.5
2.0
2.5
% p
er a
rea
CDNW WDSW
#H
Fibrosis CollagenG
0.0
0.5
1.0
1.5
2.0
CDNW
AAV luc WT
pnpla3
MT
pnpla3
AAV luc WT
pnpla3
MT
pnpla3
WDSW
His
tolo
gy s
core
**
Defining the impact of mutant PNPLA3 on metabolome and transcriptome in high fat-refined sugar diet (AAV-luc vs mt PNPLA3)
I148M PNPLA3 induces multiple metabolomics changes under Western diet conditions (vs AAV-luc)
DAGs
Oxidized AA-metabolites
nucleotides
ceramides
Plasmenyl-PC/PE
Plasmanyl PC/PEc h o w d i e t w e s t e r n d i e t
0
5 0
1 0 0
1 5 0
g r o u p s
inte
ns
ity
un
its
A A V l u c
A A V - W T P N P L A 3
A A V - M T P N P L A 3
*
triglycerides
(ADP, AMP, GMP)
• Depletion of FFA• Increased oxidized FFA• Increased AMP• Increased acylcarnitines• Decreased glutathione• Increased ceramides
WDSWPNPLA3I148M
PNPLA3WT
PNPLA3I148M
vrs AAV-Luc
PNPLA3WT
vrs AAV-Luc
C
Figure 3
Student’s t-
test (p)
log2(fold
change)
Metabolic class
Oxidized FA
Arachidonic acid-derived
oxidized FA4.98E-02 0.638
Glycerolipids
Diacylglycerols 1.29E-02 0.864
Saturated Diacylglycerols 1.10E-02 0.919
Ratio
PUFA/SFA 1.93E-02 -0.377
SM/PC 6.57E-03 -0.389
Cer/SM 2.16E-02 0.459
TG/DG 1.26E-02 -0.391
PNPLA3 I148M vs. AAV-LUC on WDSW
Gene-ontology analysis reveals an immune-inflammatory signature induced by mutant PNPLA3
Activation of STAT3 and the acute phase response by I148M PNPLA3
β actin42 kD
P-Stat3
(T705)Stat386 kD
CD WD
EV WT MT EV WT MT
STAT1 activation signature induced by mutant PNPLA3
P= 5.64e-54
Z score= 91.5
Activation of class II MHC with mutant PNPLA3
Immune reponse:
MHC Class II network activation
P= ?
Z score= ?
Cell-signaling pathway activation with disease acceleration with mtPNPLA3
Mutant PNPLA3 increases lipogenic drive, cell stress, inflammatory signals
LUC WT I148M LUC WT I148M
CDNW WDSW
PNPLA3 (I148M) activates fibrogenic signaling
AA
V l
uc
CD
AA
V l
uc
WD
AA
V- W
T C
D
AA
V- W
T W
D
AA
V- M
T C
D
AA
V- M
T W
D
0
1 0
2 0
3 0
4 0
5 0
6 0
mR
NA
(c
or
re
cte
d f
or
GA
PD
H)
*
*
0
1
2
3
4
CDNW WDSW CDNW WDSW CDNW WDSW
Vector wPNPLA3 mPNPLA3
SMA
SM
A m
RN
A
(fo
ld c
han
ge)
*
Coll 1A
42 kD
CD WD
EV WT MT EV WT MT
42 kD
46-48 kD
β actin
α-SMA
TGF-β1
CD WD
EV WT MT EV WT MT
Establishing a rational basis for using suppression of mtPNPLA3 expression as a therapeutic option
Can silencing PNPLA3 rescue the phenotype?
Mt-PNPLA3introduced
Scrambledsequences
siRNA(mt-PNPLA3)
LUC si-Scr si-PNP si-Scr si-PNP
B WDSW
GAPDH
Stat3
p-Stat3
PNPLA3
PNPLA3WT PNPLA3I148M
53
86
86
37
MW
(KD)
Silencing PNPLA3 rescues disease phenotype
0.00
0.02
0.04
0.06
His
tolo
gy
sco
re
Steatosis
*
#
PNPLA3 WT PNPLA3 I148M
His
tolo
gy
sco
re
0.0
0.5
1.0
Hepatocyte
Ballooning*
##
PNPLA3 WT PNPLA3 I148M0
1
2
Lobular Inflammation
*
#
His
tolo
gy
sco
re
PNPLA3 WT PNPLA3 I148M
0.00
0.25
0.50
0.75Fibrosis
His
tolo
gy
sco
re
PNPLA3 WT
H
Effect of mtPNPLA3 on ceramide pathways
CERAMIDE
SERINE + PALMITATE
3-KETO DIHYDRO SPHINGOSINE
SPHINGOMYELIN SPHINGOSINE
SPTLC
KDSR
SMPD CERS
DIHYDRO SPHINGOSINE
CERS
C E R S 2 C E R S 4 C E R S 5 C E R S 6
0
1
2
3
4
Re
lati
ve
mR
NA
e
xp
res
sio
n
W D -W T
W D -M T
W D -s iM T
**
* ***
*
Summary: How mutant PNPLA3 leads to NASH and fibrosis
Oxidized FA
DAG
Ceramides
α-SMA
Col1 and 3
Immune activation
p-JNK
p-STAT3
Fibrosis
Oxidative stressGSH/GSSG
TGF-β1
I148MHigh
fat diet
Sphingomyelin
Sphingosine
KDSR
Inflammation