Prenatal development and molecular characterization of conceptuses from gilts supplemented with L-arginine during early gestation

• Ano de defesa: 2020
• Autor(a) principal: Costa, Karine Assis
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa
• Palavras-chave em Português: Porcas (Animal) - Feto; Nutrigenômica; Expressão gênica; Proteínas; Fenótipo; Genética e Melhoramento dos Animais Domésticos
• Link de acesso: https://locus.ufv.br//handle/123456789/28714

Females L-arginine supplementation during gestation have been used to improve their reproductive performance through modifications of placental efficiency and conceptuses survival and development. However, the molecular and cellular mechanisms that underlie the effects of L-arginine supplementation during gestation on mother and conceptuses are not elucidated. Therefore, we aimed to evaluate the effects of gilts L-arginine supplementation during gestation on conceptuses survival and development through the phenotypic analyses of gilts and conceptuses, gene expression and protein abundance analyses of the 25 days-embryos and 35 days-fetuses from gilts not supplemented (CON) or supplemented with 1.0% L-arginine (ARG). We evaluated genes associated with developmental processes such as cell proliferation, migration, differentiation and apoptosis, conceptuses morphogenesis, growth and the epigenetics mechanisms involved in the regulation of gene expression. At the phenotypic level, we found differences between gestational ages (25 and 35 days) on gilts characteristics such as uterine weight (P<0.0001), left and right uterine horn length (P=0.001 and P=0.003), right and total ovaries weight (P=0.05 and P=0.04), with higher values at 35 days compared with 25 days, as expected, due to gestational advancement with the normal fetal development. We also found differences between gestational ages considering other gilts characteristics such as viable embryos number (P=0.05) that was higher at 25 days, which explains the higher mortality rate of fetuses at 35 days (P=0.01) and the lower coefficient of variation of conceptuses weight in this same gestational age (P=0.01). Considering diets, we found differences between CON and ARG gilts on concentrations of some metabolites, ARG gilts presented lower concentration of methionine and tyrosine (P=0.01 and P= 0.004) on the blood plasma compared to CON gilts, besides, there was a tendency to interaction between gestational age and diet for arginine blood plasma concentration in which at 25 days was a higher concentration of arginine on ARG gilts compared to CON gilts. However, at 35 days, there was a lower concentration of arginine on blood plasma from ARG gilts (P=0,06). Interestingly, we found a tendency to higher weight of ARG embryos and a higher liver weight of the embryos from ARG gilts at 25 days compared to CON embryos (P=0.07 and P=0.09, respectively). Besides that, we observed a higher expression of IGF1 gene on ARG embryos (P=0.05). However, at 35 days, the ARG fetuses presented a smaller cephalic-caudal length compared to CON fetuses (P=0.05). ARG fetuses also presented lower MTOR expression (P=0.05) as a result of higher MLST8 gene expression (P=0.04) and lower concentration of arginine on ARG gilts blood plasma, since under poor- nutrient conditions mLST8 inhibits mTOR activity. Furthermore, ARG fetuses had also a lower abundance of phospho-mTOR and phospho-AMPK proteins (P=0.006 and P=0.007). ARG embryos had lower phospho-AMPK abundance related to CON embryos (P=0.04). Even though we found differences in expression of some genes between CON and ARG embryos and fetuses, we did not find differences between CON and ARG conceptuses in expression of epigenetic genes. We conclude that the duration of L-arginine supplementation is determinant for the biological effects on gilts and conceptuses. Keywords: Fetal programming. Nutrigenomics. Gene expression. Protein abundance. Phenotype.