From the Poplar mecano-perception to visceral sensitivity in mice: role of ubiquitous transcription...

From the Poplar mecano-perception

to visceral sensitivity in mice: role of

ubiquitous transcription factor EGR-

4?Alison Accarie / 2ème année de thèse

Directeur de thèse : Pr. Michel Dapoigny

Directeurs du laboratoire : Pr. Alain Eschalier et Pr. Denis Ardid

UMR/INSERM 1107 Neuro Dol, Pharmacologie Fondamentale et Clinique de la douleur

Réunion annuelle du Groupe Français de Neuro-Gastroenterologie

20-21 juin 2013

INTRODUCTION

U1107 / Pharmacologie fondamentale et clinique de la douleur

inadequate support of chronic pain

Visceral pain

Abdominal pain

Colonic pain

• First cause for gastroenterological consultation

• Common symptoms of IBS et IBD (period of remission)

IBS : irritable bowel syndromeIBD : intestinal bowel desease

Colonic hypersensitivity

Colonic pain

2/3 of cases

INTRODUCTION

Colonic hypersensitivity

Colonic pain

2/3 of cases

Exarcerbated response to painful stimulation or not

INTRODUCTION

Peripheral sensitization (target organ)

Peripheral sensor

Mechanical sensor

INTRODUCTION

Inflammation mediator

Identification of a new transcription factor in case of mechanical stimulation in Arabidopsis & Poplar sp. (Equipe MECA, UMR PIAF Clermont-Ferrand)

INTRODUCTION

PTaZFP2

Transcription factor

Zinc finger

Early expression

Martin, 2009

INTRODUCTION

Martin, 2009

INTRODUCTION

Martin, 2010

Martin, 2009

Mechanosensor in plant genetic equivalent in animal

PtaZFP2 EGR-4

INTRODUCTION

Martin, 2010

EGR Family:

4 subtypes (EGR-1)

Transcription factor/ Early Gene Response

Zinc fingers structure/ Same DNA binding sequence : GCC G/TGG GCG

INTRODUCTION

EGR-4

Male unfertility

Inflammatory process in cultured T cell

Surexpression in somatosensory cortex after mechanical stimulation.

Involvement in visceral

mechanosensation?

Expression of EGR-4 in colon?

OBJECTIFS

Target genes?

Sensibilization?

Involvement in visceral

mechanosensation?

Expression of EGR-4 in colon?

OBJECTIFS

Target genes?

Sensibilization?

distension

Euthanasia

1h30 2h0 45 min30 min15 min10 min5 min 1h

PROTOCOLE

Western Blot

Increase of total form of EGR-4 45 minutes after distension

Expression of EGR-4

EGR-4 Colon

Increase of total form of EGR-4 45 minutes after distension

Expression of EGR-4

EGR-4 Colon

Increase of total form of EGR-4 120 minutes after distension

Expression of EGR-4

EGR-4 DRGv

Increase of total form of EGR-4 90 minutes after distension

Expression of EGR-4

EGR-4 DRGv

Expression of EGR-4

Increase of total form of EGR-4 45 minutes after distension

EGR-4 Spinal Cord

Expression of EGR-4

Increase of total form of EGR-4 45 minutes after distension

EGR-4 Spinal Cord

Conclusion & percpectives

Conclusion

News tools

expression in colon, DRG and spinal cord.

Modulation expression with mechanical stimulation

Future studies

mRNA expression studies (qPCR)

Identification of target genes (micro-array)

Different models of colonic Hypersensitivity

Conclusion & perspectives

Conclusion

News tools

expression in colon, DRG and spinal cord.

Modulation expression with mechanical stimulation

Acknowledgement

Thank you for your attention

Monique Etienne

Ludivine Boudieu

Emilie Muller

Agathe Gelot

Frederic Carvalho

Denis Ardid