title: Confocal fluorescence assessment of bioenergy/redox status of dromedary camel (Camelus dromedarius) oocytes before and after in vitro maturation.
abstract: BACKGROUND
  Reproductive biotechnologies in dromedary camel (Camelus dromedarius) are less developed than in other livestock species. The in vitro maturation (IVM) technology is a fundamental step for in vitro embryo production (IVP), and its optimization could represent a way to increase the success rate of IVP. The aim of the present study was to investigate the bioenergy/oxidative status of dromedary camel oocytes before and after IVM by confocal microscopy 3D imaging.
  
  
  METHODS
  Oocytes were retrieved by slicing ovaries collected at local slaughterhouses. Recovered oocytes were examined before and after IVM culture for nuclear chromatin configuration and bioenergy/oxidative status, expressed as mitochondria (mt) distribution and activity, intracellular Reactive Oxygen Species (ROS) levels and distribution and mt/ROS colocalization.
  
  
  RESULTS
  The mean recovery rate was 6 oocytes/ovary. After IVM, 61% of oocytes resumed meiosis and 36% reached the Metaphase II stage (MII). Oocyte bioenergy/redox confocal characterization revealed changes upon meiosis progression. Immature oocytes at the germinal vesicle (GV) stage were characterised by prevailing homogeneous mt distribution in small aggregates while MI and MII oocytes showed significantly higher rates of pericortical mt distribution organized in tubular networks (P<0.05). Increased mt activity in MI (P<0.001) and MII (P<0.01) oocytes compared to GV stage oocytes was also observed. At any meiotic stage, homogeneous distribution of intracellular ROS was observed. Intracellular ROS levels also increased in MI (P<0.01) and MII (P<0.05) oocytes compared to GV stage oocytes. The mt/ROS colocalization signal increased in MI oocytes (P<0.05).
  
  
  CONCLUSIONS
  This study provides indications that qualitative and quantitative indicators of bioenergy and oxidative status in dromedary camel oocytes are modified in relation with oocyte meiotic stage. These data may increase the knowledge of camel oocyte physiology, in order to enhance the efficiency of IVP procedures.
authors.forename: Roberto
authors.initials: R
authors.lastname: Russo
authors.forename: Davide
authors.initials: D
authors.lastname: Monaco
authors.forename: Marcello
authors.initials: M
authors.lastname: Rubessa
authors.forename: Khalid A
authors.initials: KA
authors.lastname: El-Bahrawy
authors.forename: Ashraf
authors.initials: A
authors.lastname: El-Sayed
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Martino
authors.forename: Benedicte
authors.initials: B
authors.lastname: Beneult
authors.forename: Francesca
authors.initials: F
authors.lastname: Ciannarella
authors.forename: Maria E
authors.initials: ME
authors.lastname: Dell'Aquila
authors.forename: Giovanni M
authors.initials: GM
authors.lastname: Lacalandra
authors.affiliation: Section of Clinics and Animal Productions, Department of Emergency and Organ Transplantation (DETO), University of Bari Aldo Moro, Str Prov Casamassima, km 3, Bari Valenzano 70010, Italy. m.filioliuranio@gmail.com.
authors.forename: Manuel
authors.initials: M
authors.lastname: Filioli Uranio
mesh_terms: D000818:Animals; D002162:Camelus; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D018613:Microscopy, Confocal / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D054315:Oocyte Retrieval / Q000379:methods; D009865:Oocytes / Q000254:growth & development* / Q000378:metabolism*; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species