de Brun V, Meikle A, Casal A, Sequeira M, Contreras-Solís I, Carriquiry M, Forcada F, Sosa C, Abecia J A
Laboratorio de Técnicas Nucleares, Facultad de Veterinaria, Montevideo, Uruguay.
Departamento de Producción Animal y Pasturas, Facultad de Agronomía, Montevideo, Uruguay.
J Anim Physiol Anim Nutr (Berl). 2015 Aug;99(4):710-8. doi: 10.1111/jpn.12261. Epub 2014 Oct 15.
This study investigated whether a 22-day period of undernutrition (half maintenance) could affect maternal endocrine responses and liver gene expression during early pregnancy (day 7). Thirty-five ewes were fed 1.5 (n = 15) or 0.5 (n = 20) their maintenance requirements and slaughtered on day 7 of the oestrus cycle or pregnancy (oestrus = day 0). Insulin, IGF, leptin and non-esterified fatty acids (NEFA) were determined on days -14, 0 and 7. Transcripts of the IGF family and adipokines receptors were determined in the liver by real-time RT-PCR. Underfed animals presented lower body weight and body condition, greater plasma concentration of NEFA, and lower plasma concentrations of leptin, insulin and IGF1 compared to adequately fed animals. Underfed ewes presented greater hepatic expression of IGFBP2 than well-fed ewes, but tended to have lesser expression of IGFBP5. While no effect of undernutrition on IGFBP4 and ADIPOR2 mRNA expressions was observed, they were increased by pregnancy in underfed animals. This study shows that undernutrition modifies endocrine profiles and hepatic gene expression of IGFBP2 and 5. The pregnancy status increased hepatic gene expression of IGFBP4 and ADIPOR2 mRNA in undernourished ewes.
本研究调查了为期22天的营养不足（维持量的一半）是否会影响妊娠早期（第7天）母羊的内分泌反应和肝脏基因表达。35只母羊分别按照维持需求量的1.5倍（n = 15）或0.5倍（n = 20）进行饲养，并在发情周期或妊娠的第7天（发情日 = 第0天）屠宰。在第-14天、第0天和第7天测定胰岛素、胰岛素样生长因子（IGF）、瘦素和非酯化脂肪酸（NEFA）。通过实时逆转录聚合酶链反应（RT-PCR）测定肝脏中IGF家族和脂肪因子受体的转录本。与营养充足的动物相比，营养不足的动物体重和体况较低，NEFA的血浆浓度较高，而瘦素、胰岛素和IGF1的血浆浓度较低。营养不足的母羊肝脏中IGFBP2的表达高于营养良好的母羊，但IGFBP5的表达则趋于较低。虽然未观察到营养不足对IGFBP4和ADIPOR2 mRNA表达有影响，但在营养不足的动物中，妊娠会使其表达增加。本研究表明，营养不足会改变内分泌状况以及IGFBP2和5的肝脏基因表达。妊娠状态会增加营养不足母羊肝脏中IGFBP4和ADIPOR2 mRNA的基因表达。
