ENFERMEDADES MONOGÉNICAS DE LA CÉLULA BETA...
Transcript of ENFERMEDADES MONOGÉNICAS DE LA CÉLULA BETA...
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
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
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
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10
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50
60
70
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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
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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