title: Supplementation with the histone deacetylase inhibitor trichostatin A during in vitro culture of bovine embryos.
abstract: Trichostatin A (TSA) is a histone deacetylase inhibitor that induces histone hyperacetylation and increases gene expression levels. The aim of the present study was to establish a suitable condition for the use of TSA in in vitro cultures of bovine embryos, and to determine whether TSA would increase blastocyst rates by improvement of chromatin remodelling during embryonic genome activation and by increasing the expression of crucial genes during early development. To test this hypothesis, 8-cell embryos were exposed to four concentrations of TSA for different periods of time to establish adequate protocols. In a second experiment, three experimental groups were selected for the evaluation of embryo quality based on the following parameters: apoptosis, total cell number and blastocyst hatching. TSA promoted embryonic arrest and degeneration at concentrations of 15, 25 and 50 nM. All treated groups presented lower blastocyst rates. Exposure of embryos to 5 nM for 144 h and to 15 nM for 48 h decreased blastocyst hatching. However, the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay (TUNEL) assay revealed similar apoptosis rates and total cell numbers in all groups studied. Although, in the present study, TSA treatment did not improve the parameters studied, the results provided background information on TSA supplementation during in vitro culture of bovine embryos and showed that embryo quality was apparently not affected, despite a decrease in blastocyst rate after exposure to TSA.
authors.affiliation: UNESP-Via de Acesso Professor Paulo Donato Castellane, CEP 14884-900, Jaboticabal, São Paulo, Brazil. claraslade@gmail.com
authors.forename: Clara Slade
authors.initials: CS
authors.lastname: Oliveira
authors.forename: Naiara Zoccal
authors.initials: NZ
authors.lastname: Saraiva
authors.forename: Marcela Maria
authors.initials: MM
authors.lastname: de Souza
authors.forename: Tatiane de Almeida Drummond
authors.initials: Tde A
authors.lastname: Tetzner
authors.forename: Marina Ragagnin
authors.initials: MR
authors.lastname: de Lima
authors.forename: Joaquim Mansano
authors.initials: JM
authors.lastname: Garcia
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001755:Blastocyst / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D002417:Cattle / Q000196:embryology*; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000166:cytology; D005260:Female; D005307:Fertilization in Vitro; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006877:Hydroxamic Acids / Q000494:pharmacology*; D008297:Male
chemical_list: D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; C012589:trichostatin A