Saul J. Karpen, M.D., Ph.D. - paris-nash-symposium.org fileSaul J. Karpen, M.D., Ph.D. Separating...
Transcript of Saul J. Karpen, M.D., Ph.D. - paris-nash-symposium.org fileSaul J. Karpen, M.D., Ph.D. Separating...
Saul J. Karpen, M.D., Ph.D.
Separating the metabolic benefits from lipoprotein abnormalities
associated with FXR agonists--gut vs. liver effects
Raymond F. Schinazi Distinguished Biomedical Chair
Professor of Pediatrics
Paris July 1, 2016
No Financial Disclosures
OCA/plac. x 72 w.
ALT
FXR AGONIST • Chol
• HDL
• LDL
• ~ TG
-0,25
-0,15
-0,05
0,05
0,15
0,25
OCA (126)
Plac (131)
Chol HDL LDL TG
D L
ipid
(m
M)
P= 0.0009
P= 0.01
P< 0.0001 P= 0.88
Gastro 2015 PMID:25500425
0
50
100
150
200
250
300
Chol LDL HDL TG
Plac
OCA (10 mg)
OCA (25 mg)
* *
* *
EO
T [
Day 8
5]
Lip
id L
evels
(m
g/d
l)
FXR AGONIST • Chol #
• HDL
• ~ LDL #
• ~ TG
# : Different from NASH
17 D
28 D
Pencek, Diabetes, Obesity & Metabolism 2016, PMID:27109453
OCA in 68 Healthy Volunteers: Lipid Analyses
Transporters & FXR: Ileal & Hepatic Components of the EHC
Ileum
Liver
Schaap, Nat Rev GI Hep 2014
LXR FXR
MAPK
PI3K
PKC
TGR5
AP1 FAS
TRAIL
PGC1
CAR
VDR
PXR
Cell
Signaling
Apoptosis
Nuclear
Receptors
JNK
p38MAPK
ERK1/2
SHP
FGF19
S1PR2
Multiple Molecular Roles for Bile Acids
Cholic Acid Chenodeoxycholic acid
Lithocholic Acid Z-Guggulsterone
FXR Agonists
FXR Antagonists
GW4064
EC50: 4-10 M 37-80 nM 20 M
IC50:
Deoxycholic acid
19-50 M
6--ethyl-CDCA
(Obeticholic acid) 99 nM
10 M
Makishima Science 1999
Parks Science 1999
Wang Mol Cell 1999
Urizar Science 2002
Yu JBC 2002
Pellicciari J Med Chem 2002
Hawkins JCI 2002
Dussault JBC 2003
Downes Mol Cell 2003
Carter Ped Res 2007 10-30 M
Stigmasterol
10 M
Fexaramine
25 nM
Fexarine
38 nM
Fexarene
36 nM
AGN31
2 M (also RXR)
2016, PMID: 26812075 OCA x 24 h: FXR targets
Caveats:
• “The hPCLS used for this study were obtained from patients with a
high BMI (35–43 kg/m2).”
• Dedifferentiated human cells in culture—CYP7A1 & CYP8B1 were not
downregulated.
SHP BSEP OST MDR3 FGF19
Protein
RNA:
J Clin Invest. 2015;125:386–402.
Intestinal FXR Antagonism
improves NASH in mice
Intestinal FXR Agonism
improves NASH in mice
Essential, but seemingly contradictory effects of FXR & BA signaling in NAFLD
Intestinal FXR ko protects against
HFD-induced hepatic steatosis
Nat Med. 2015;21:159–165.
Fexaramine (Intestinal FXR agonist) improves
HFD-induced hepatic steatosis
Glyco-Muricholic Acid:
• Intestinal FXR antag.
• Brown Fat activity
• Intest. Ceramides
NAFLD & NASH:
FXR Agonism or FXR Antagonism
Both work Why?
Intact Enterohepatic
BA Recirculation
ASBT
Ileal ASBT
Inhibition
Interrupted Enterohepatic
BA Recirculation
ASBT
Ileal ASBT inhibition will
improve the hepatic and
whole body response to
HFD in mice
Hypothesis:
Colon
BA’s
Microbial BA metab.
TGR5 signaling
BA Pool size
Liver
BA Synthesis
Cholesterol
Ileum
BA Uptake
FXR-FGF15/19 signaling
ALIOS (45% fat; 0.2% cholesterol), + Added Sugars in the Drinking Water
Chow
HFD
Asbti [SC-435] x 16wk
HFD Asbti
HFD:
Asbti: 0.006% SC-435, 10 mg/kg/day
Mice: Male, C57BL6J, 4-6 weeks, n=7-16/group
Study Design & Endpoints
4 8 12 16 . . . . . 0
Weeks • Weekly Body Weights
• Weekly Caloric & fluid intake
• Week 15 GTT, ITT
• Week 16
• Serum Liver Indices
• Feces Bile Acids
• Ileum RNA
• Colon RNA
• Liver Histology
• Lipids & Bile Acids
• RNA-Seq
• RNA & Protein
• Hydroxyproline
• Statistics: Mean ± SD
• ANOVA
Tetri LH. Am J Physiol GI 2008 Nov;295(5):G987–95.
Mells JE J Nutr Biochem. 2015 Mar;26(3):285–92. AASLD 2015
SC-435 Inhibits Ileal ASBT function
Liver
0
1
2
3
4
Chow HFD HFD Asbti
a
b
a
Cyp7a1
0
1
2
3
4Cyp8b1
a
b
a
Chow HFD HFD Asbti
Rela
tive
gen
e e
xp
res
sio
n
Colon
0
5
1 0
1 5
2 0 Ilbp
a a
b
Chow HFD HFD Asbti
Rela
tive
gen
e e
xp
res
sio
n
ASBT
Fec
al B
ile
Ac
ids
(
M/2
4 h
r)
HFD Asbti
Feces
HFD
a
b
0
1
2
3
Fgf15
a
b
c
Chow HFD HFD Asbti
Ileum
Rela
tive
gen
e e
xp
res
sio
n
Asbt
HFD Asbti
Chow HFD
Shp
a
b
a
AASLD 2015
Glu
co
se (
mg
/dL
)
Time (mins)
ASBTi Improves Glucose Tolerance
Chow HFD HFD Asbti
* *
*
Chow
HFD + Asbti
HFD
GT
T A
UC
a
b
a
*: Significantly different from HFD + Asbti
GTT
AASLD 2015
Triglycerides Cholesteryl Ester
(g
/mg
liv
er)
(g
/mg
liv
er)
a
b
a
a
b
a
Chow HFD HFD Asbti
Chow HFD HFD Asbti
ASBTi Reduces Hepatic Lipids, But Not Total Bile Acids
Chow HFD HFD Asbti
(pm
ol/
mg
liv
er
tiss
ue
)
Total Bile Acids
AASLD 2015
a
b b
Chow HFD HFD Asbti
Liver Wt/Body Wt
ASBTi Improves Hepatic NAS & Steatosis Scores
Chow HFD HFD + Asbti
NAS Score
Chow HFD HFD Asbti
a
b
c
Steatosis Score
Chow HFD HFD Asbti
a
b
c
AASLD 2015
FXR Antagonist FXR Agonist
HFD
58% 42%
HFD + Asbti
83%
17%
Bile
Aci
d (
pm
ol/
mg
tiss
ue
) ASBTi Markedly Alters Hepatic BA Composition
* * * * * -TMCA b-TMCA w-TMCA THDCA TUDCA -MCA b-MCA
FXR Antagonist
HFD
HFD + Asbti
TCA TCDCA TDCA TLCA CA
*
*
*
FXR Agonist
*
AASLD 2015
HFD
Insulin resistance
Hyperglycemia Hyperinsulinemia
ChREBP
Lipogenic genes TG
SREBP-1c LXR Hepatic
cholesterol
FXR Hepatic
BA Composition
ASBTi
ASBTi
ASBTi
Hepatic
Steatosis
ASBT
Hypothesized Mechanisms of Action of ASBTi in Liver
FXR Antagonist
FXR Agonist
HFD
58% 42%
HFD + Asbti
83%
17%
Ileal ASBT inhibition Markedly Alters Hepatic BA Composition
TMCA’s THDCA TUDCA
TCA TCDCA TDCA
AASLD 2015
March 2016, PMID: 26708144
Nature. 2014 Mar 26.
HFD, 11w of VSG in mice KO = FXR-/-
Intact BA signaling, through its receptor, FXR,
mediates the response to Bariatric Surgery
Tilg NEJM June 23, 2016
Interaction of Diet (PC), microbes, BAs, Genes (FMO3) CV Disease
Bile acid based therapeutic trials (~ 200 in clinicaltrials.gov)
FXR agonists: Obeticholic Acid
TGR5 agonists:
ASBT inhibitors:
NorUDCA:
NASH
PBC
PSC PSC
Satiety
Constipation
Pruritus in cholestasis (ALGS, PFIC’s)
IBS-C
PSC
Glycocholic Acid: BA Synthesis Defect
BA Sequestrant: Colesevelam Diabetes
NASH
Obesity
BA diarrhea
Alcohol
Fibrosis
Summary: FXR & the Lipids in NASH
• Bile acid (BA) biology: Opportunities for discovering new
linked components of the Gut-Liver-Microbe-Gene Axis
– Differential effects of FXR & BAs in Ileum, Colon, Liver, Fat, …
– Individual BA’s have distinct functional properties
• FXR Agonists in NAFLD & NASH: Lipid Issues
– Reduces CYP7A1 & BA synthesis
– Total Cholesterol
– LDL
– HDL
• Further evidence that we will need to attack NASH
from multiple therapeutic angles – FXR Agonism & Antagonism both improve NASH in mice
– ASBT inhibition improves NASH in mice
• Reduces Hepatic TG & Cholesterol
Saul Karpen, MD, PhD
Paul Dawson, PhD
Astrid Kosters, PhD
Anuradha Rao, PhD
Angelica Amanso, PhD
JP Berauer, MD
Gina Ramirez
Funding (NIH) • R01 DK056239
• R01 DK047987
• Philanthropies:
• Alpard Foundation
• Spain Fund
• Moss Fund
Anya Mezina,MD MSCR
Courtney Ferrebee
Jamie Mells, PhD
Kim Pachura
Jianing Li, PhD
Grace Wynn
Prabhu Shankar, MD
Emory University (Saul-Paul Lab)
Hong Yin, MD (Pathology)
Dean Jones, PhD (Metabolomics)
Sophia Banton
Shuzhao Li
Hao Wu, PhD (School of Public Health)
Emory University
Brad Keller, PhD (Lumena/Shire)
Ken Setchell, PhD
Wujuan Zhang, PhD
Cincinnati Children’s
HDL Pathway targets LDL Pathway targets
Genes by OCA:
• Abca1
• Tgm2
• Fgl1
• Npc1l1
• Angptl4
• Hif1
• Ghr