ENFERMEDADES MONOGÉNICAS DE LA CÉLULA BETA PANCREÁTICA

Antonio L. Cuesta Muñoz

Centro para el Estudio de la Enfermedades de la Célula β – DRI-Málaga.Fundación IMABIS-Carlos Haya

Cádiz, 22 de Octubre de 2010

Nadia Cobo Vuilleumier(Contratada SAF)

Pablo Rodríguez Bada(Técnico F. IMABIS)

Ana Gavito Collado(Técnico Contr. SAS)

Centro para el Estudio de las Enfermedades de laCélula Beta Pancreática

alcm@fundacionimabis.org

Hospital Regional UniversitarioCARLOS HAYA Málaga

GCK-MD / GCK-hypoBenjamin GlaserTiinamija TuomiAndrew HattersleyPascale de LonlayC. Bellanné-Chantelot Fabrizio Barbetti Sameer Kassem Pascual SanzThomas MeissnerJacques RahierMarkku LaaksoShomi BhattacharyaM.D. Bautista

Elena BaixerasAntonio BernadFranz MartinFrancisco BedoyaBernat SoriaBenoit GauthierJ. Dominguez Bendala

Ingenieria Tisular

Centro para el Estudio de las Enfermedades de laCélula Beta Pancreática

Colaboradores

alcm@fundacionimabis.org

ENFERMEDADES MONOGÉNICAS DE LACÉLULA BETA PANCREÁTICA

GK

•Hiperinsulinemia Monogénica

•Diabetes Monogénica (DN, D. no N. / MODY)

•Hipoglucemia Monogénica

•Entidades bien definidas

Enfermedades Monogénicas de la célula-β Pancreática

•Impacto en el diagnóstico clínico.

¿Que nos aporta la definición etiológica y clínica de las enfermedades monogénicas de la célula-β pancreática?

Posibilidad de aprender de los errores de la naturaleza.

“Modelos humanos”

1º

•A baby girl presented at birth with severe hypoglycemia.

•Birth weight of 5,200 grams

•In spite of high dose of diazoxide, with and without the somatostatin analog, octreotide, she developed frequent hypoglycaemic seizures.

•Her insulin at the time of hypoglycemia of 52 mg/dL was recorded to be 8 IU/mL. Despite frequent feeding and high dose diazoxide of up to 33 mg/kg/day, hypoglycemic seizures occurred frequently and her blood glucose level was never above 80 mg/dL.

•At age 35m, she underwent a near-total pancreatectomy (~80%).

Case report

S. Kassem et al. NEJM 2010

•Two months after surgery hypoglycemic seizure recurred, while her blood glucose readings were 45-50mg/dl.

•Therapy with diazoxide was re-instituted, albeit at a smaller dose of 6 mg/kg/day, but it was sufficient to keep her blood glucose levels within the normal range.

•The proband’s father also had very severe hypoglycemia, unresponsive to medical therapy that was diagnosed in early infancy. A near-total pancreatectomy was performed at the age of 36 month and he subsequently developed post-surgical diabetes mellitus.

Case report

Genetic study ► A heterozygous missense mutation in GCK (V91L).

S. Kassem et al. NEJM. 2010

Histological study ► Normality

50µm50µm

BV

Age-matched controlGK – V91L

S. Kassem et al. NEJM. 2010

GK – V91L

0

10

20

30

40

50

60

70

80

90

Islet Size (µm2)

Perc

ent o

f Isl

ets

in e

ach

size

gro

up

ControlKATP-HIGCK-HI, HeadGCK-HI, Tail

0

2,000

4,000

6,000

8,000

10,000

12,000

Age-matchedControls GK-HYPO

Mea

n Ar

ea o

f Isl

ets

(mic

rom

eter

2 )

A BKATP HI HeadTail

****

*

S. Kassem et al. NEJM 2010

10µm

Age-matched controlGK – V91L

10µm

GCK- hypo: β- cell Proliferation and apoptosis

Ki 67 Stain

S. Kassem et al. NEJM. 2010

120 µm 120 µm

120 µm 120 µm

Insulin 1 Insulin 2

Insulin 3 Insulin 4

age-matched control GK – Y214C

focal hyperinsulinism diffuse hyperinsulinism

Cuesta-Muñoz et al. Diabetes 53:2164; 2004

Age-matched controlGCK – S64F

•12 years of age.

•No obese.

•Minimum amount of diazoxide, if some.

•She loves basketball.

•Normal life.

Case report

Near-total pancreatectomy (~80%).

20,000 islets2,5 times larger

Proliferation

Human model of Highly efficient islets

Creation of the insulinoma INS-1E cell lines constitutively expressing GK, the two mutant variants or the control using lentivirus technology.

GSIS is maintained in the INS-1E cells overexpressing the mutant variant E442K.

Overexpression of GK-E440G and GK-E442K protects INS-1E cellsagainst low (3 mM) and high (20 mM) glucose-mediated apoptosis but has not impact on proliferation at 72 hours. * p < 0,05

Farmacogenética

•Diferentes etiologías de los defectos de la célula-βvan ha responder de forma muy diferente a la terapia.

•Terapia “individualizada”.

•Posibilidad de interrelacionar estudios de genética molecular, fisiología humana y patofisiología molecular.

¿Que nos aporta la definición etiológica y clínica de las enfermedades monogénicas de la célula-β pancreática?

2º

DM-GCK >>> DM2 >>> ADO

DM-HNF-1α >>> DM1 >>> INSULINA

DM-HNF-1α >>> DM2 >>> ADO >>> INSULINA

DM-HNF-4α >>> DM1 >>> INSULINA

DM-HNF-1β >>> DM1 >>> INSULINA

DNP-Kir6.2 >>> DM1 >>> INSULINA

Enfermedades Monogénicas de la célula-β Pancreática

TRATAMIENTOS PREVIOS.

DM-GCK >>> DIETA / CEV / ADO (DNP >>> INSULINA)

DM-HNF-1α >>> SULFONILUREA / INSULINA

DM-HNF-4α >>> INSULINA

DM-HNF-1β >>> INSULINA

DNP-Kir6.2 >>> SULFONILUREAS / INSULINA

Enfermedades Monogénicas de la célula-β Pancreática

TRATAMIENTOS FARMACOGENÉTICO ACTUAL.

Mechanism for the excellent insulin secretory response by the HNF1α in the β-cell

GDHSCHADGlutamate

α-KG

KREBS

ATP/ADP

KirK+

Depolarization

Ca2+

Ca2+

Insulin

Insulin

GLUT 2

Glucose

Glucose GK

G6P

Ca2+ Channel

Leucine

Mitochondria

Somatostatin -

-

+

HNF-4αHNF-1αHNF-1βIPF-1NeuroD1

Nuclei

Pyruvate

GlycolysisEndoplasmicReticulum

Ca2+ StoresK+SUR1 6.2

Sites of defect in HNF-1a deficiency models

sulphonylureas

... Yo es que creía que la única forma de dejar de “pincharme” insulina era con la cosa del transplante o con eso de las “cédulas madres”....

...es que...es como si ya no tuviera diabetes...

Sulphonylurea sensitivity in a patient with an HNF1α mutation

HbA1c fell5% with 5mgglibenclamide

4

5

6

7

8

9

10

11

8 8,5 9 9,5 10 10,5 11 11

,5 12 12,5 13 13

,5Years from Diagnosis

SU stoppedMet started

SU startedMet stopped

HbA

1c %

Pearson et al. Diab Med 2000

-7

-6

-5

-4

-3

-2

-1

0

1

1 2

p<0.0001

Gliclazide Metformin

Changein fasting plasma glucose

withtreatment(mmol/l)

HNF1αMODY

Type 2HNF1αMODYType 2

Gliclazide

Metformin

HNF1α patients respond better to Gliclazide than Type 2 patients

Pearson et al Lancet 2003

Reduced insulin secretion as a result of a Kir6.2 mutation in PNDM

Pearson et al NEJM 2006

Insulin secretion in presence of sulphonylureas

Pearson et al NEJM 2006

Glucemia menor y mejor controlada

Zung et al JCEM 04

Insulin pump 7.5 mg Glibenclamide

Gracias