The drawbacks of paternal obesity on sperm biology, preimplantation embryo morphokinetics, and its transgenerational impacts Georges Raad To cite this version: Georges Raad. The drawbacks of paternal obesity on sperm biology, preimplantation embryo mor- phokinetics, and its transgenerational impacts. Agricultural sciences. Université Côte d’Azur, 2016. English. NNT : 2016AZUR4143. tel-01492786 HAL Id: tel-01492786 https://tel.archives-ouvertes.fr/tel-01492786 Submitted on 20 Mar 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. 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Université de Nice-Sophia Antipolis Ecole doctorale SVS ED85 Sciences-Vie-Santé THESE DE DOCTORAT Pour obtenir le grade de Docteur en biologie de l‘université de Nice-Sophia Antipolis Spécialité: Recherche clinique et thérapeutique Soutenue par: Georges RAAD The drawbacks of paternal obesity on the sperm biology, the preimplantation embryo morphokinetics, and its transgenerational impacts Directrice de thèse : Valérie GRANDJEAN Co-directrice de thèse : Mira HAZZOURI Soutenue le 14 Décembre 2016 Jury : Rapporteurs : Sophie ROUSSEAUX Roger MIEUSSET 1 Table of Contents THESIS ABSTRACT ................................................................................................................6 RESUME ...................................................................................................................................8 LIST OF FIGURES ................................................................................................................ 10 LIST OF TABLES .................................................................................................................. 13 CHAPTER1 THE DRAWBACKS OF OBESITY ON THE GLOMERULOPATHY, TESTICULAR HOMEOSTASIS AND SPERM EPIGENOME .......................................... 14 I- THE BODY WEIGHT HOMEOSTASIS .................................................................................... 14 A- The human body homeostasis...................................................................................... 14 B- The body weight management ..................................................................................... 18 B. 1 The metabolic energy network ............................................................................. 18 B.1.1 The digestive system: intake, processing and distribution of foodstuffs ............. 18 B.1.2 Cells and molecules implicated in glucose homeostasis and energy management 19 a) Energy storing cells ...................................................................................... 20 a. 1 The white adipose tissue ........................................................................... 20 a. 2 The liver ................................................................................................... 22 b) Energy consuming cells ................................................................................ 23 B. 2 The control of food intake .................................................................................... 24 II- WEIGHT IMBALANCE: OBESITY COMPLICATIONS ............................................................... 25 A- The drawbacks of obesity on kidney homeostasis ........................................................ 28 A. 1 Kidney physiology .................................................................................................. 28 A. 1.1 Obesity-related glomerulopathy (ORG) ................................................................ 31 A. 1.1.a The effect of obesity on the glomerular histology .......................................... 31 A. 1.1.b Decline in renal function and obesity ............................................................ 31 a) Renal hemodynamics........................................................................................ 31 b) Hyperglycemia and hyperlipidemia: ................................................................. 33 B- The drawbacks of obesity on testicular homeostasis .................................................... 34 B. 1 Male reproductive system anatomy .......................................................................... 34 B.1.1 The effects of obesity on testicular anatomy, sexual function and seminal plasma biochemistry ................................................................................................................... 36 B. 2 Testicular histology and physiology ......................................................................... 37 B.2.1 The interstitial compartment................................................................................. 38 a) Blood vessels ....................................................................................................... 38 b) Leydig cells ......................................................................................................... 38 b.1 Overview ...................................................................................................... 38 b.2 Steroidogenesis ............................................................................................. 39 b.3 The effect of obesity on Leydig cell physiology and androgen homeostasis... 40 2 c) Immune cells ....................................................................................................... 41 c.1 Phagocytosis, proliferation and physiology of Leydig cells ............................... 41 c.2 Immunoregulation and inflammation ................................................................ 42 c.3 The effect of obesity on testicular immune cells ............................................... 42 B.2.2 Tubular compartment ........................................................................................... 43 a) Peritubular cells ................................................................................................... 44 b) Sertoli cells .......................................................................................................... 45 b. 1 Overview ...................................................................................................... 45 b. 2 Cytological features ...................................................................................... 45 b. 3 Sertoli cell functions ..................................................................................... 45 b. 4 The effects of obesity on Sertoli cell functions .............................................. 49 c) Germ cells............................................................................................................ 52 c. 1 Spermatogonia .............................................................................................. 52 c. 2 The meiotic cells ........................................................................................... 54 c. 3 The spermiogenesis ....................................................................................... 55 c. 4 The impact of male obesity on sperm parameters and embryo development .. 58 III- EPIGENETIC INHERITANCE OF PATERNAL ACQUIRED OBESITY ............................................ 60 A- Epigenetic control of gene expression during spermatogenesis and early embryogenesis 60 A. 1 DNA methylation ................................................................................................. 60 A. 1.1 DNA methylation reprogramming in mouse germ cells and pre-implantation embryos 62 A. 1.2 The drawbacks of abnormal DNA methylation profile in gametes ................. 63 A. 2 DNA hydroxymethylation and DNA demethylation ............................................. 65 A. 2.1 5-hmC dynamics during mouse spermatogenesis and embryo development .. 67 A. 3 Chromatin modifications ...................................................................................... 69 A. 3.1 Chromatin structure in somatic cells ............................................................. 69 A. 3.2 Chromatin remodelling during spermatogenesis ............................................ 72 a) Spermatogonia ................................................................................................. 72 b) Meiotic cells ..................................................................................................... 73 c) Spermatids and spermiogenesis ........................................................................ 74 c. 1 The incorporation of histones variants into the chromatin ............................. 74 c. 2 Histones hyperacetylation............................................................................. 74 c. 3 Replacement of histones by transition proteins ............................................. 75 c. 4 Replacement of TP by protamine.................................................................. 75 d) Sperm chromatin .............................................................................................. 76 d.1 Nucleoprotamine-bound sperm chromatin ..................................................... 77 d.2 Nucleosome-bound sperm chromatin ............................................................ 77 d.3 Matrix attachment regions (MARs) ..............................................................