Cardiac remodeling in pressure overload and myocardial infarction [Elektronische Ressource] : role of PKC_e63 and gp130 signaling pathways / von Praphulla Chandra Shukla

Praphulla Chandra Shukla

Sujets

• Gesundheit

Informations

• Publié par: gottfried_wilhelm_leibniz_universitat_hannover
• Publié le: 01 janvier 2006
• Nombre de lectures: 37
• Langue: English
• Poids de l'ouvrage: 9 Mo

Extrait

Cardiac Remodeling in Pressure Overload and Myocardial
Infarction: Role of PKC ε and gp130 Signaling Pathways


Der Naturwissenschaftlichen Fakultät
der Gottfried Wilhelm Leibniz Universität Hannover
zur Erlangung des Grades
Doktor der Naturwissenschaften
(Dr. rer. nat.)
genehmigte Dissertation


von
M.Sc. Praphulla Chandra Shukla
geboren am 19.01.1977 in Fatehpur, India
2006

Referent: Prof. Dr. Walter Müller
Korreferent: Prof. Dr. Jörg Schmidtke
thTag der Promotion: 7 December 2006
Key Words: Myokardinfarkt, Myokardhypertrophie, gp130
Myocardial Infarction, Myocardial Hypertrophy, gp130




INDEX
SYNOPSIS..................................................................................................................................................................I
LIST OF ABBREVIATIONS................................................................................................................................. V
LIST OF FIGURES.............................................................................................................................................. VII
LIST OF TABLES..................................................................................................................................................IX
1 INTRODUCTION (A) .............................................................................................................................. 1
1.1 HYPERTROPHIC REMODELING OF THE HEART............................................................................................. 1
1.2 CELLULAR AND MOLECULAR RESPONSE OF CARDIOMYOCYTES TO BIOMECHANICAL STRETCH .............. 2
1.3 SIGNAL TRANSDUCTION IN CARDIAC HYPERTROPHY ................................................................................. 6
1.3.1 PKC and Cardiac Hypertrophy ......................................................................................................... 8
1.3.2 PKC Redundancy in Cardiac Hypertrophy..................................................................................... 10
1.4 PKCε KNOCKOUT MOUSE TO STUDY CARDIAC HYPERTROPHY............................................................... 11
2 AIM OF THE STUDY (A) ..................................................................................................................... 13
3 RESULTS (PART A) .............................................................................................................................. 14
3.1 CARDIAC PHENOTYPE OF PKCε KNOCKOUT MICE ................................................................................... 14
3.2 PRESSURE OVERLOAD TRIGGERED SIMILAR HYPERTROPHIC RESPONSES IN KNOCKOUT AND WILDTYPE
MICE........................................................................................................................................................... 16
3.3 PRESSURE OVERLOAD INCREASED COLLAGEN EXPRESSION IN KNOCKOUT MICE................................... 19
3.4 PKCε KNOCKOUT MICE SHOW DIASTOLIC DYSFUNCTION AFTER PRESSURE OVERLOAD....................... 21
3.5 UPREGULATION OF PKCδ IN PKCε KNOCKOUT MICE AFTER PRESSURE OVERLOAD .............................. 22
3.6 DIFFERENTIAL ACTIVATION OF MAPK SIGNALING PATHWAY IN KNOCKOUT MICE AFTER PRESSURE
OVERLOAD................................................................................................................................................. 23
3.7 APOPTOSIS IN PKCε KNOCKOUT AND WILDTYPE MICE AFTER PRESSURE OVERLOAD............................ 25
3.8 INDUCTION OF COL Iα1 EXPRESSION BY MECHANICAL STRETCH IN FIBROBLASTS................................. 25
4 DISCUSSION (PART A)........................................................................................................................ 28
5 INTRODUCTION (B) ............................................................................................................................ 31
5.1 THE PATHOPHYSIOLOGY OF MYOCARDIAL INFARCTION .......................................................................... 31
5.2 EXPERIMENTAL MI IN MICE AS A TOOL TO INVESTIGATE PATHOPHYSIOLOGICAL PROCESSES IN THE
INFARCTED HEART..................................................................................................................................... 32
5.3 PRO-INFLAMMATORY CYTOKINES IN THE INFARCTED AND THE FAILING HEART..................................... 33
5.3.1 Roles of the IL-6/gp130 Receptor System in Heart Failure............................................................ 34
5.4 THE MECHANISTIC INSIGHT INTO THE IL-6/GP130 SIGNALING CASCADE ................................................ 36
5.4.1 IL-6 Cytokine Family ....................................................................................................................... 37
5.4.2 The Structure of gp130 Receptor..................................................................................................... 38
5.4.3 Mutations in the gp130 Receptor..................................................................................................... 42
5.5 ROLE OF THE GP130 RECEPTOR SYSTEM IN THE ADULT HEART ............................................................... 46
5.6 ROLE OF SIGNALING PATHWAYS ACTIVATED BY THE GP130 RECEPTOR SYSTEM: MEK/ERK, JAK/STAT
AND PI3-K/AKT ......................................................................................................................................... 47

5.6.1 MEK/ERK Signaling ........................................................................................................................ 48
5.6.2 JAK/STAT Signaling......................................................................................................................... 49
5.6.3 PI3-K/Akt Signaling ......................................................................................................................... 49
6 AIM OF THE STUDY (B)...................................................................................................................... 51
7 RESULTS (PART B) .............................................................................................................................. 52
7.1 GENERATION OF CARDIOMYOCYTE SPECIFIC GP130 MUTANT MICE........................................................ 52
7.2 VERIFICATION OF CARDIOMYOCYTE SPECIFIC DELETION OF THE GP130 IN GP130-KO MICE.................. 56
7.3 CHARACTERIZATION OF THE CARDIAC PHENOTYPES OF GP130 MUTANT MICE AT BASELINE ................ 57
7.4 LIF INDUCES IMPAIRED DOWNSTREAM SIGNALING IN MICE HARBOURING CARDIOMYOCYTE SPECIFIC
MUTATIONS IN THE GP130 RECEPTOR ....................................................................................................... 57
7.5 CARDIOMYOCYTE SPECIFIC MUTATIONS IN THE GP130 RECEPTOR AFFECT THE ACTIVATION OF THE
MEK/ERK AND JAK/STAT SIGNALING................................................................................................... 59
7.6 INCREASED POST-MI MORTALITY IN GP130-KO AND MEK/ERK-KO BUT NOT IN JAK/STAT-KO MICE
............................................................................................................................................................... 61
7.7 LEFT VENTRICULAR FUNCTIONAL ANALYSIS ........................................................................................... 62
7.8 LEFT VENTRICULAR MORPHOMETRIC ANALYSIS...................................................................................... 63
7.8.1 Substantially Larger Infarct in gp130-KO and MEK/ERK-KO...................................................... 63
7.8.2 Gp130 Mutant Mice Show an Impaired Hypertrophic Response ................................................... 63
7.9 GENE EXPRESSION ANALYSIS IN GP130 MUTANT MICE POST-MI............................................................ 64
7.9.1 Reduction in Expression of skm- α-actin Gene ................................................................................ 64
7.9.2 Enhanced Induction of ANP Gene Expression in gp130 Mutant Mice........................................... 65
7.10 ENHANCED APOPTOSIS IN THE INFARCT BORDER ZONE OF GP130 MUTANT MICE .................................. 66
8 DISCUSSION (PART B)........................................................................................................................ 69
9 MATERIALS AND METHODS ...........................................................................................................74
A. CHEMICALS AND REAGENTS...................................................................................................................... 74
B. KITS............................................................................................................................................................ 75
C. ANTIBODIES ............................................................................................................................................... 75
D. INSTRUMENTS ............................................................................................................................................ 76
E. OTHER MATERIALS..................................................................................................................................... 76
9.1 MICE..................................................................................................................................................