Transcript nancy France

Journal Club
Zannad F, McMurray JJ, Krum H, van Veldhuisen DJ, Swedberg K, Shi H,
Vincent J, Pocock SJ, Pitt B; the EMPHASIS-HF Study Group.
Eplerenone in Patients with Systolic Heart Failure and Mild Symptoms.
N Engl J Med. 2010 Nov 14. [Epub ahead of print] 10.1056/nejmoa1009492
Brad P. Barnett, Yousang Hwang, Martin S. Taylor, Henriette Kirchner, Paul T.
Pfluger, Vincent Bernard, Yu-yi Lin, Erin M. Bowers, Chandrani Mukherjee, WooJin Song, Patti A. Longo, Daniel J. Leahy, Mehboob A. Hussain, Matthias H.
Tschöp, Jef D. Boeke, Philip A. Cole
Glucose and Weight Control in Mice with a Designed Ghrelin O-Acyltransferase
Inhibitor
10.1126/science.1196154
2010年11月25日 8:30-8:55
８階 医局
埼玉医科大学 総合医療センター 内分泌・糖尿病内科
Department of Endocrinology and Diabetes,
Saitama Medical Center, Saitama Medical University
松田 昌文
Matsuda, Masafumi
Rates of Hyperkalemia ( >5.5 mEq/L) in EPHESUS by Proteinuria
and History of Diabetes*
Rates of Hyperkalemia ( >5.5 mEq/L) in EPHESUS by
Proteinuria and History of Diabetes*
Eplerenone
(N=508)
n (%)
Placebo
(N=363)
n (%)
* Diabetes assessed as positive medical history at baseline;
proteinuria assessed by positive dipstick urinalysis at baseline.
INSERM, Centre d’Investigation Clinique 9501 and Unite 961, Centre Hospitalier Universitaire, and the
Department of Cardiology, Nancy University, Nancy, France (F.Z.); the British Heart Foundation Cardiovascular
Research Centre, University of Glasgow, Glasgow, United Kingdom ( J.J.V.M.); the Department of Epidemiology
and Preventive Medicine, Centre of Cardiovascular Research and Education in Therapeutics, Monash University,
Melbourne, VIC, Australia (H.K.); the Department of Cardiology, Thorax Center, University Medical Center,
Groningen, the Netherlands (D.J.V.); the Department of Emergency and Cardiovascular Medicine, Sahlgrenska
Academy, University of Gothenburg, Gothenburg, Sweden (K.S.); Pfizer, New York (H.S., J.V.); the Department
of Medical Statistics, London School of Hygiene and Tropical Medicine, London (S.J.P.); and University of
Michigan School of Medicine, Ann Arbor (B.P.).
N Engl J Med 2010.
10.1056/nejmoa1009492 nejm.org
BACKGROUND
Mineralocorticoid antagonists improve
survival among patients with chronic,
severe systolic heart failure and heart
failure after myocardial infarction. We
evaluated the effects of eplerenone in
patients with chronic systolic heart failure
and mild symptoms.
METHODS
In this randomized, double-blind trial, we
randomly assigned 2737 patients with New
York Heart Association class II heart failure
(mild symptoms) and an ejection fraction of
no more than 35% to receive eplerenone
(up to 50 mg daily) or placebo, in addition
to recommended therapy. The primary
outcome was a composite of death from
cardiovascular causes or hospitalization for
heart failure.
We attempted to minimize the risk of hyperkalemia by excluding patients with a baseline serum potassium level
above 5.0 mmol per liter and a baseline estimated GFR below 30 ml per minute per 1.73 m2.
Eplerenone was started at a dose of 25 mg once daily and was increased after 4 weeks to 50 mg once daily (or
started at 25 mg on alternate days, and increased to 25 mg daily.
Figure 2. Hazard Ratios for
Hospitalization for Heart Failure or
Death from Cardiovascular Causes (the
Primary Outcome) with Eplerenone
versus Placebo, According to
Prespecified Subgroups.
The subgroups are based on baseline
demographic and clinical characteristics.
The size of the square corresponds to the
number of patients with an event. Data are
missing for some patients in some
subgroups. ACE denotes angiotensinconverting enzyme, ARB angiotensinreceptor blocker, BNP B-type natriuretic
peptide, CRT cardiac-resynchronization
therapy, GFR glomerular filtration rate, ICD
implantable cardioverter–defibrillator, and
LVEF left ventricular ejection fraction.
RESULTS
The trial was stopped prematurely, according to prespecified
rules, after a median follow-up period of 21 months. The
primary outcome occurred in 18.3% of patients in the
eplerenone group as compared with 25.9% in the placebo
group (hazard ratio, 0.63; 95% confidence interval [CI], 0.54
to 0.74; P<0.001). A total of 12.5% of patients receiving
eplerenone and 15.5% of those receiving placebo died
(hazard ratio, 0.76; 95% CI, 0.62 to 0.93; P = 0.008); 10.8%
and 13.5%, respectively, died of cardiovascular causes
(hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P = 0.01).
Hospitalizations for heart failure and for any cause were
also reduced with eplerenone. A serum potassium level
exceeding 5.5 mmol per liter occurred in 11.8% of patients in
the eplerenone group and 7.2% of those in the placebo
group (P<0.001).
CONCLUSIONS
Eplerenone, as compared with placebo,
reduced both the risk of death and the risk
of hospitalization among patients with
systolic heart failure and mild symptoms.
(Funded by Pfizer; ClinicalTrials.gov number, NCT00232180.)
Message/Comments
糖尿病では高カリウム血症という副作用で
使いにくいが心不全にはよい薬物。（アク
トスとの併用？）
www.sciencexpress.org / 18 November 2010 / Page 1 / 10.1126/science.1196154
Background: Ghrelin is a gastric peptide
hormone that stimulates weight gain in
vertebrates. The biological activities of
ghrelin require octanoylation of the peptide
on Ser3, an unusual post-translational
modification that is catalyzed by the enzyme
ghrelin O-acyltransferase (GOAT).
Methods: Here, we describe the
design, synthesis, and
characterization of GO-CoA-Tat,
a peptide-based bisubstrate
analog that antagonizes GOAT.
GO-CoA-Tat potently inhibits
GOAT in vitro, in cultured cells,
and in mice.
Fig. 1. GO-CoA-Tat is a
bisubstrate inhibitor that
inhibits GOAT, lowering acyl
ghrelin levels.
(A) Mechanism-based design
strategy. Lipid-enzyme
interaction, not shown, may
also be important.
(B) Structure of GO-CoA-Tat
and synthetic scheme for
bisubstrate inhibitors that
consist of three components:
coenzyme A, octanoylated
ghrelin peptide and a Tat
peptide; Ahx-aminohexanoate.
(C) Temporal inhibition of acyl
but not desacyl ghrelin
production by 6 μM GO-CoATat in GOAT/preproghrelintransfected HeLa cells.
(D) Dose-response reduction
of acyl but not desacyl ghrelin
levels by GO-CoA-Tat in
GOAT/preproghrelintransfected HeLa cells after 24
h incubation.
Fig. 2. GO-CoA-Tat targets
GOAT directly in vitro and in
a structure specific manner.
(A) Structure of GO-CoA-Tat
analogs (1–6).
(B) Acyl and desacyl ghrelin
levels after treatment with 6
μM GO-CoA-Tat (1) and
analogs (2–6) from
GOAT/preproghrelintransfected HeLa cells after
24 h.
(C) In vitro acyltransferase
inhibition assay (5 min
reaction) with microsomal
recombinant GOAT.
(D) UV crosslinking of
solubilized GOAT by biotintagged, benzophenylalanine
analogs of GO-CoA-Tat
(L5BP, F4BP) (5 μM).
Competitor is GO-CoA-Tat at
100 μM. Immunoblots of
cross-linked GOAT were
visualized with streptavidin,
loading was checked with
anti-FLAG.
Fig. 3. Effects of GO-CoA-Tat
on blood ghrelin and body
weight in mice.
(A) Serum acyl ghrelin levels
in WT C57BL6 mice on an
MCT diet treated
intraperitoneally with 11
μmol/kg GO-CoA-Tat vs. D4Tat control (n = 5) after 6, 12,
and 24 h. (*P < 0.05, **P <
0.01, ***P < 0.001, std. errors
shown). The changes in acyl
ghrelin over 24 h in control
animals are neither
statistically significant (P >
0.2), nor reproducible in other
experiments.
(B) Serum desacyl ghrelin
levels for experiment in Fig.
3A.
(C) Percent acyl ghrelin for
experiment in Fig. 3A.
Fig. 3. Effects of GO-CoA-Tat
on blood ghrelin and body
weight in mice.
(D) Body weights in wt
C57BL6 mice on an MCT diet
treated with 11 μmmol/kg GOCoA-Tat (red, n = 5) or vehicle
(black, n = 6) for 1 mo (*P <
0.05; conventional ** and ***
omitted for clarity, standard
errors shown).
(E) Fat mass in wt mice
measured by QMR for
experiment in 3D.
(F) Body weights in ghrelin
knockout C57BL6 mice on an
MCT diet treated with 11
μmol/kg GOCoA- Tat (red, n =
5) or vehicle (black, n = 5) for
1 mo (standard errors shown).
The larger error bars
compared to data in Fig. 3D
likely represent the broader
distribution of starting weights.
Also note that the scales differ
in the two panels, contributing
to the larger error bars seen
here.
(G) Fat mass in ghrelin
knockout mice measured by
QMR for experiment in Fig.
3F.
Fig. 4. GO-CoA-Tat
increases insulin,
decreases glucose levels,
and down-regulates islet
cell UCP2 mRNA.
(A) C57BL6 wt mice
raised on normal mouse
chow and treated with 8
μmol/kg GO-CoA-Tat (n =
4) experienced a
statistically significant
increase in insulin
secretion and
(B) a statistically
significant decrease in
blood glucose as
compared to control mice
(treated with D4-Tat (n =
4)) when compound was
administered 24 h prior to
IP glucose challenge
(2.5g/kg) (*P < 0.05, **P <
0.01, std. errors shown).
Fig. 4. GO-CoA-Tat increases
insulin, decreases glucose
levels, and down-regulates
islet cell UCP2 mRNA.
(C) Immunohistochemical
staining of mouse islets. Left
panel – insulin (green) ghrelin
receptor (GHSR) (red) and
cell nuclei stained with DAPI
(blue). Middle panel – staining
of islet for ghrelin (white) and
insulin (green) demonstrates
dual staining and ghrelin
positive and insulin negative
cells. Right panel – closeup of
unmerged images in boxed
area of middle panel.
(D) QRT-PCR of islets and
(E) gastric fundus isolated
from mice treated with
inhibitor 24 h prior to isolation
and mRNA expression
relative to control (n = 3).
Results: Intraperitoneal
administration of GO-CoA-Tat
improves glucose tolerance and
reduces weight gain in wild-type
mice but not in ghrelin-deficient
mice, supporting the concept
that its beneficial metabolic
effects are due specifically to
GOAT inhibition.
Conclusion: In addition to
serving as a research tool for
mapping ghrelin actions, GOCoA-Tat may help pave the way
for clinical targeting of GOAT in
metabolic diseases.
Message/Comments
グレリン作用を抑制することで肥満治療が
できる可能性がある。