ABSTRACT
In vitro oocyte maturation (IVM) protocols can be improved by adding chemical supplements to the culture media. Tretinoin is considered an important retinoid in embryonic development and its association with lipid-core nanocapsules (TTN-LNC) represents an innovative way of improving its solubility, and chemical stability, and reducing its toxicity. The effects of supplementing IVM medium with TTN-LNC was evaluated by analyzing production of reactive oxygen species (ROS), S36-phosphorilated-p66Shc levels and caspase activity in early embryonic development, and expression of apoptosis and pluripotency genes in blastocysts. The lowest concentration tested (0.25µM) of TTN-LNC generated higher blastocyst rate, lower ROS production and S36-p66Shc amount. Additionally, expression of BAX and SHC1 were lower in both non-encapsulated tretinoin (TTN) and TTN-LNC-treated groups. Nanoencapsulation allowed the use of smaller concentrations of tretinoin to supplement IVM medium thus reducing toxic effects related with its use, decreasing ROS levels and apoptose frequency, and improving the blastocyst rates.
Subject(s)
Antioxidants/pharmacology , Blastocyst/drug effects , Drug Carriers , Embryo Culture Techniques/veterinary , Fertility Agents, Female/pharmacology , In Vitro Oocyte Maturation Techniques/veterinary , Nanocapsules , Reactive Oxygen Species/metabolism , Tretinoin/pharmacology , Animals , Antioxidants/chemistry , Apoptosis/drug effects , Blastocyst/metabolism , Blastocyst/pathology , Caspase 3/metabolism , Caspase 7/metabolism , Cattle , Chemistry, Pharmaceutical , Dose-Response Relationship, Drug , Embryonic Development/drug effects , Female , Fertility Agents, Female/chemistry , Gene Expression Regulation, Developmental , Nanomedicine , Phosphorylation , Pregnancy , Shc Signaling Adaptor Proteins/metabolism , Signal Transduction/drug effects , Tretinoin/chemistry , bcl-2-Associated X Protein/metabolismABSTRACT
Single nucleotide polymorphisms (SNPs) in the p53 gene have been studied extensively in humans. The aims of this study were to determine the frequency of the Arg/Pro SNP in p53 in Thoroughbred mares on one stud in Brazil and to correlate p53 genotypes with reproductive performance. SNPs were detected by PCR-restriction fragment length polymorphism in blood samples from 105 horses and confirmed by sequencing. The allele frequency in Thoroughbred mares at codon 72 in exon 4 was 73.3% Arg/Pro, 17.1% Arg/Arg and 9.6% Pro/Pro. The presence of Arg/Pro was significantly associated with abortion (P=0.02), while Pro/Pro mares had a lower probability of abortion (P<0.05). Using a logistic regression model, the dominance effect was significant (P=0.044; odds ratio 7.94) for abortion and additive effects were not significant (P=0.26). p53 may play a role in equine reproduction.
