Cryopreservation of bovine embryos is used to efficiently implant surrogate mothers. It has been widely accepted that high lipid content in the oocyte interrupts its survival during freeze-thaw cycles. Serum component in the culture medium is thought to increase the embryo`s lipid contents. Conversely, L-carnitine stimulates lipid metabolism by transporting long chain fatty acids into the mitochondria. Objective of this study was to analyze the effect of L-carnitine supplementation in IVM medium and defined IVC medium on the development, lipid contents and the cryosurvival of bovine IVF embryos. 0.0, 1.5, 3.0 and 6.0 mM L-carnitine was supplemented in IVM medium, respectively (IVM-LC 0.0, LC 1.5, LC 3.0 and LC 6.0). Development rate from the 2cell to the morula stages was higher in IVM-LC 3.0 groups than those of IVM-LC 6.0 (p<0.05). But there were no significant differences among the other groups in the blastocyst rates and lipid content results. When 0.0, 1.5, 3.0 and 6.0 mM L-carnitine were supplemented in IVC medium (IVC-LC 0.0, LC 1.5, LC 3.0 and LC 6.0), development competence was not significantly different between those embryos. Lipid contents of embryos treated L-carnitine (IVC-LC 1.5, 3.0 and 6.0) were significantly lower than embryos of non-treated group. L-carnitine was supplemented 0.0, 1.5, 3.0, 6.0 mM during IVM and 3.0 mM during IVC (LC 0.0 - 3.0, LC 1.5 – 3.0, LC 3.0 – 3.0, LC 6.0 – 3.0) and cryosurvival of blastocysts confirmed after freezing-thawing. There were no significant differences on development, but LC 3.0 – 3.0 was significantly lower lipid contents than other groups. And LC 3.0 – 3.0 had better survival rates and hatched rates of blastocysts than LC 0.0 – 0.0. In conclusion, supplementation of L-carnitine in defined IVC medium decreases lipid contents. And L-carnitine supplementation improves cryosurvival and developmental ability of bovine IVF embryos.
The early-onset familial Alzheimer's disease (EOFAD/ FAD), the less common type of Alzheimer's disease (AD) currently affects a vast number of individuals worldwide. This type is being inherited as an autosomal dominant fashion. Missense mutations on Amyloid precursor protein (APP) and Presenilins 1 and 2 (PSEN1 & PSEN2) are known as major genetic factors in FAD. Conversely, missense mutations on microtubule-associated protein tau (MAPT) are also thought to involve. Up to date, several triple-transgenic animal models with muted forms of the human APP, PSENs and MAPT have been reported. Compared to other animals, canines are more emotional and their disease signs can be easily diagnosed. This attempt was to develop a triple transgenic canine model for the AD. We have obtained the coding sequences of APP, PSEN1 and MAPT from Dana-Farber/Harvard Cancer Center DNA resource core at HMS and incorporated several common AD mutations. The transgenic construct is composed of hNSE (ENO2) promoter-driven three AD genes fused together with modified 2A sequences. It was transfected into the canine fetal fibroblasts which were then used to perform somatic cell nuclear transfer (SCNT). The viable transgenic embryos were obtained after in vitro culture and the GFP was detected. In this study, we have successfully produced viable triple transgenic canine cloned embryos using SCNT technique. These transgenic canine embryos will be further developed into canines with FAD. The transgenic canines will be a good candidate in the AD research field.