β-Cell Dysfunction & Apoptosis · Apoptosis Pancreatic β-Cell O D BLOO OLIGOMERIZATION AMYLIN HYPERGLYCEMIA Amylin Oligomers HYPERAMYLINEMIA HYPERINSULINEMIA Calcium dsreglation

Cardiotoxicity of Hyperamylinemia

β-Cell Dysfunction & Apoptosis

Pancreatic β-CellOD

AMYLIN

BLOO AMYLIN

OLIGOMERIZATION HYPERGLYCEMIAAmylin Oligomers

HYPERAMYLINEMIA HYPERINSULINEMIACalcium

d sreg lation

Hypertrophy, Remodeling Heart Failure

dysregulation

Florin Despa Department of PharmacologyUniversity of California, Davis

Patients with Obesity and Type-2 Diabetes Present Cardiac Amylin AccumulationA source of cardiomyocyte Ca2+ dysregulationA source of cardiomyocyte Ca dysregulation

Collaborators Lab MembersCollaboratorsKenneth B. Margulies (UPenn)Heinrich Taegtmeyer (UTHS)

Lab MembersKaleena JacksonKatie GuglielminoA d NDonald Steiner (U of Chicago)

Sanda Despa (UC Davis)Donald M Bers (UC Davis)

Andy NguenTracy TangTerry PangDonald M. Bers (UC Davis)

Anne Knowlton (UC Davis)Peter Havel (UC Davis)

Terry Pang

Funds: AHA, NSF, Vision Grant - UC Davis

sr seas

e3

HYPOTHESIS

Type

-2

iabe

tes

sulin

Ris

k fo

rdi

ac D

is

2

ulinulin tanc

e

T Di

InRC

ard 1

Ctl InsuInsu

Res

isHyperglycemiaDyslipidemiay

cell

HF

eatic

β-c

Hyperinsulinemia

panc

re Hyperamylinemia

BLOODToxic Amylin Oligomers

RATIONALE: selection of human heart samples

LeanNon-Failing Heartsg

Lean, Non-diabetesFailing Hearts

AmylinOligomers

Failing Hearts

Obese/OverweightNon-Failing Hearts

Obese/OverweightFailing Hearts

AmylinOligomers

gdistinct amylin oligomer

size distributions

Type-2 DiabetesFailing Hearts

Failing Hearts

Failing Hearts

Amylin Oligomers Accumulate in HeartFailing vs. Non-failing

L NF OW/OB-HF

Anti-Amylin Antibody TAmylin Trimers

400

500 **

**Con

trol

)

L-NF OW/OB-HF 50

15 tetrameroctamer

200

300

400

B-N

F

B-H

F

F

** **

rimer

s (%

C

10 kDa

15

trimer

tet a e

0

100

L-N

F

L-H

F

OW

/OB

OW

/OB

DM

-HF

Am

ylin

T

16-MER FAILING

Larger Amylin Oligomers

400

500

**

Con

trol

)OCTAMER

TETRAMERNON-FAILING

200

300

F

*

OW

/OB

-N

F

OB

-HF

n Le

vel (

% C

DIMERTRIMER NON-FAILING

0

100L-

NF

L-H

F

DM

-H

O

OW

/O

Am

ylin

Cardiac Amylin Deposition in Type-2 Diabetic Humans

PANCREAS HEARTControlHEART HEART

20 µm20 µm 20 µm20 µm

tibod

y

aini

ng

HEARTHEART

myl

in A

nt

o R

ed S

ta

Ant

i-Am

Con

g

20 µm20 µm

Amylin Oligomers Circulate Through the Blood Obese Diabetes and Kidney FailureBlood Obese, Diabetes and Kidney Failure

Obesity and Type-2 Diabetes With Kidney Failure

160 *

%)

160**

%)tro

l)

150

175

)

T2DM

T2DM

T2DM

T2DM

T2DM

obese

Obesity and Type 2 Diabetes With Kidney Failure

80

120

BMW

IAPP

(%

80

120

MW

IAPP

(%ev

el (%

Con

75

100

125

150

P le

vel (

a.u.

)

HealtyBMI < 25

M M MM

0

40

Ctl OW

/OB

Hig

h M

0

40

Ctl DMH

igh

MIA

PP L

e

L

L

CE12

0E16

0E17

0E18

0E19

0E11

0E13

0E15

0

0

25

50

IAPP

E E E E E E E E

Acute Effect of Amylin on Isolated Cardiac MyocytesMyocytes

Human: KCNTATCATQRLANFLVHSSNNFGAILSSTNVGSNTY

Rat: KCNTATCATQRLANFLVRSSNNLGPVLPPTNVGSNTY

0 6

0.8

cay

(s)

1500 Controlh-amylinr-amylin)

***

0.4

0.6

nient

Dec

500

1000 Systolic***

Ca]

i (nM

)

******

0 0

0.2

Ctl

h-am

ylin

r-am

ylin

a Tr

ansi

0

500

Diastolic

[C

0.0Ca0.0 0.5 1.0 1.5 2.0

Frequency (Hz)

Amylin Oligomers Alter the Structure of Sarcolemma in Isolated Cardiac Myocytes

Thaps+0Ca/0Na200 +carboxyeosin

4

5

*/s)

Sarcolemma in Isolated Cardiac MyocytesPassive Ca2+ Leak

Ctl+ ] i (n

M)

2

3

4

eak

(nM

/

501 min

CtlAmylin

[Ca2

0

1

2

Ctl

Am

ylin

Ca2+

l

2.5 µm 2.5 µm

control

Animal Models

Rat Amylin

pancreas

Human Amylin

pancreas pa c eas

UCD-T2DM rat

pa c eas

HIP rat

Non-fasting Blood Glucose Level

180

200

cose

l)

Non fasting Blood Glucose Level

120

140

160

CD

-T2D

M

IPBlo

od G

lu(m

g/d l

100 UC

HIB

Amylin Accumulates in the Heart of HIP Ratst

UC

DH

IP ra

t D-T2D

M

20 µm20 µm

M rat

HeartPancreas Heart Pancreas

25 kDa64

Lysates DMPD

10 kDa

15 kDa

16kD

32

HIP UCD-T2TM

kDaHIP rat

Myocardial Insulin Signaling in HIP vs. UCD T2DM ratsUCD-T2DM rats

2.0

1.5t (

a.u.

)

0 5

1.0

Akt

/Akt

0.0

0.5

Ctl

UC

DHI

P

0

p-A

100 10Insulin: 0 0 10 10 0 0 10 10 10 10 10 100 0

Ctl HIP UCD

AktpAkt

Akt

Cardiac Amylin Oligomer Accumulation Alters Ca2+ Cycling in HIP Rats

1500 CtlHIP

*** 1500 CtlUCD

HIP rat UCD raty g

1000

HIP

Systolic******

a]i (

nM)

1000Systolic

UCD

a]i (

nM)

0 0 0 5 1 0 1 5 2 00

500

Diastolic***

***[Ca

0

500Diastolic

[Ca

diastolic 0.0 0.5 1.0 1.5 2.0

Frequency (Hz)0.0 0.5 1.0 1.5 2.0

Frequency (Hz)

0 8 * 0 8

dysfunction

0.4

0.6

0.8

ay ti

me

(s) *

0.4

0.6

0.8

ay ti

me

(s)

0.0

0.2Dec

a

Ctl

HIP

0.0

0.2Dec

a

Ctl

UC

D

Contractile Dysfunction in Pre-diabetic HIP RatsHIP Rats

80

120

*

P (m

mH

g)

6000

8000

mH

g/s)

Maximum Rate of P Ri

40

80

IP IPd Sy

stol

ic P

2000

4000

IP IPP/dt

max

(mmPressure Rise

0 RI HI

End

Left-Ventricular End Systolic Pressure

0 RI HId

/s)

8mH

g)

Left-Ventricular End Diastolic Pressure

4000

6000*

min

(mm

Hg/

Maximum Rate of Pressure Fall

4

6

8

tolic

P (m

m0

2000

RIP

HIP

-dP/

dtm Pressure Fall

0

2

RIP

HIP

End

Dia

stcollab. with A. Knowlton (UC Davis)

Cardiac Amylin Oligomer Accumulation Triggers Remodeling of SERCA

CtlPDSERCA *

Ctl DMPD

Triggers Remodeling of SERCA

DMPDSERCA

PLB

**DMCtl PD

HIP rat

NCX*

DMCtl PD

0 40 80 120

*

% vs. Ctl120

Ctl)

40

80

RC

A (%

vs.

C

DMCtl PDUCD rat

0 DMCtl

PDSER