Impact of L-carnitine supplementation on the in vitro developmental competence and cryotolerance of buffalo embryos

Abstract

Background and Aim: Despite many trials, buffalo embryos have poor cryosurvivability because of their high lipid content. L-carnitine was found to be a lipid-reducing agent when added to oocyte and embryo culture media. The study aimed to determine the most effective concentration of L-carnitine to improve the oocyte developmental competence and cryotolerance of buffalo embryos. Materials and Methods: In vitro maturation and embryo culture media were supplemented with four concentrations of L-carnitine: 0 (control), 0.25, 0.5, and 1 mM. Good-quality embryos on 7 days were vitrified using mixtures of dimethyl sulfoxide and ethylene glycol at two concentrations (3.5 and 7 M). Results: The result showed that the cleavage and morula rates were significantly (p<0.05) higher in the 0.5 mM group. Blastocyst rates were significantly (p<0.05) higher at both 0.5 and 1 mM. The rates of viable embryos directly after thawing were significantly (p<0.05) increased in the 0.5 mM group. No significant difference was found in embryos cultured for 24 h after warming among all the groups. Conclusion: The addition of L-carnitine at a concentration of 0.5 mM to the culture media improves the oocyte developmental competence and cryotolerance of buffalo embryos directly after warming but not after 24 h of culture. Nevertheless, further studies must identify how L-carnitine exerts its beneficial micromechanisms.

A comparative study of preimplantation embryos development of young and aged mice treated with L-carnitine

“…of fertilization in both young and aged mice and decreased the mean of embryonic development of the 2-cell embryo of grade D, that characterized by unequal size blastomeres and sever fragmentation. It has been demonstrated that LC increases the preimplantation and developmental competence of embryos in experimental animals, due to the improvement of cytoplasmic and nuclear maturation of oocytes that play an initial role in the consequent development of fertilized oocyte to embryo, and the reduction of ROS levels 27 , which may be due to its vital role in increasing glutathione (GSH) levels inside the cells that can prevent free radical damage to embryos 28 . On the other hand, it has been reported that LC tends to induce nuclear maturity and increase the number of early embryos in camels 29 .…”

Criotolerancia De Embriones Bovinos Cultivados Individualmente en Un Medio Suplementado Con L-Carnitina

“…Khanmohammadi et al (2016), informaron el incremento del porcentaje de blastocistos (P < 0.01) y el número total de células de embriones de ratón debido al efecto antioxidante de la L-carnitina a una concentración de 0.5 mg/mL. Otros autores, refieren que la L-carnitina durante la MIV, reduce la toxicidad del embrión inducida por el estrés oxidativo al disminuir las ERO y aumentar el GSH intracelular en ovocitos ovinos (Mishra et al, 2016) y aumenta la tasa de división y el porcentaje de embriones de búfalo (El-Sokary et al, 2021).…”

“…De la misma manera, la adición de L-carnitina a una concentración de 0.5 mM al medio de MIV, mejora el desarrollo del ovocito, la competencia y criotolerancia de embriones de búfalo posterior a la desvitrificación, pero no después de 24 h de cultivo. (El-Sokary et al, 2021).…”

“…Los efectos de la L-carnitina por adición a los medios en los embriones producidos in vitro sobre la calidad y criotolerancia son muy discutidos y contradictorios (Zolini et al (2019);Carrillo-González et al (2020); Li et al (2021);El-Sokary et al (2021). No obstante, algunos autores refieren la eficacia de una concentración de 0.6 mg/mL de L-carnitina en el medio de MIV para aumentar el glutatión intracelular, la maduración nuclear y la tasa de división de embriones bovinos (Phongnimitr et al, 2013) y de ratón (Zare et al, 2015), así como su desarrollo hasta el estadio de blastocistos.…”