Amino acids and vitamins prevent culture-induced metabolic perturbations and associated loss of viability of mouse blastocysts.

Abstract

Culture of in-vivo-developed mouse blastocysts in a simple culture medium based on a balanced salt solution supplemented with carbohydrates for 3 h significantly perturbed embryo metabolism. Maximal perturbation occurred after just 6 h of culture. Similarly, culture of rat blastocysts in a simple culture medium for 3 h also resulted in perturbed metabolism. Cultured mouse and rat blastocysts both had an abnormally elevated rate of glycolysis of approximately 100% after culture (P < 0.05). Rates of pyruvate oxidation by mouse blastocysts were also significantly reduced after culture in a simple medium for 6 h (P < 0.01). Furthermore, the developmental competence of mouse blastocysts after transfer was significantly reduced by just 6 h of culture in a simple medium (P < 0.05). Addition of Eagle's amino acids or vitamins to the culture medium reduced the perturbation of both the glycolytic activity and oxidative capacity of cultured mouse blastocysts and acted in synergy to further the inhibition. Importantly, culture with amino acids and vitamins prevented any loss of viability of mouse blastocysts after culture for 6 h. It can be concluded that the mouse blastocyst is sensitive to its environment and that culture-induced stress results in the loss of normal cellular function, as manifested in this case by an abnormal pattern of glucose utilization and loss of viability.