Sadri H, Saremi B, Dänicke S, Rehage J, Mielenz M, Hosseini A, Sauerwein H
Department of Clinical Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz 5166616471, Iran; Institute of Animal Science, Physiology & Hygiene Unit, University of Bonn, Bonn 53111, Germany.
Institute of Animal Science, Physiology & Hygiene Unit, University of Bonn, Bonn 53111, Germany.
Domest Anim Endocrinol. 2018 Jul;64:93-101. doi: 10.1016/j.domaniend.2018.04.004. Epub 2018 Apr 17.
Pigment epithelium-derived factor (PEDF) is evolving as metabolic regulatory protein. Albeit mostly considered in only pathological conditions related to excess energy intake resulting in obesity and insulin resistance, PEDF is likely to be involved in other physiological processes such as the homeorhetic adaptation of metabolism to lactation. We aimed to characterize the expression of PEDF and its association to the concomitant mobilization of body reserves during lactation in nonobese subjects. This mobilization is particularly distinct in dairy cows, and we therefore assessed the mRNA expression of PEDF and its putative receptors in different tissues in 2 trials with dairy cows fed with or without conjugated linoleic acids (CLAs). Conjugated linoleic acids depress milk fat synthesis and may thus reduce the drain of energy via milk. In pluriparous cows, the serum PEDF concentrations and the mRNA abundance in subcutaneous adipose tissue (scAT), as well as the hepatic and scAT mRNA abundance of the putative receptors, adipose triglyceride lipase, and laminin receptor 1, changed over time of sampling (day -21 until day 252 relative to calving). Conjugated linoleic acid treatment was associated with reduced PEDF concentrations in serum and lower PEDF mRNA abundance in scAT on day 21 postpartum. Comparing different tissues from primiparous cows, PEDF mRNA was highest in the liver, followed by scAT, visceral adipose tissue (AT), and mammary gland, and lowest in the muscle. Significant changes in PEDF expression with time of sampling were limited to AT in primiparous and pluriparous cows. Our data support a regulatory role for PEDF. The similarities between the time course of the serum concentrations of PEDF and its mRNA abundance in scAT may point to a regulatory role for AT rather than the liver for PEDF in dairy cows.
色素上皮衍生因子（PEDF）正逐渐成为一种代谢调节蛋白。尽管PEDF大多仅在与能量摄入过多导致肥胖和胰岛素抵抗相关的病理状况中被考虑，但它可能参与其他生理过程，比如代谢对泌乳的顺势调节适应。我们旨在表征非肥胖受试者泌乳期间PEDF的表达及其与身体储备同时动员的关联。这种动员在奶牛中尤为明显，因此我们在两项试验中评估了饲喂或未饲喂共轭亚油酸（CLA）的奶牛不同组织中PEDF及其假定受体的mRNA表达。共轭亚油酸会抑制乳脂肪合成，从而可能减少通过乳汁的能量消耗。在经产奶牛中，血清PEDF浓度以及皮下脂肪组织（scAT）中的mRNA丰度，以及假定受体、脂肪甘油三酯脂肪酶和层粘连蛋白受体1的肝脏和scAT mRNA丰度，在采样时间（相对于产犊的第 -21天至第252天）内发生了变化。共轭亚油酸处理与产后第21天血清中PEDF浓度降低以及scAT中PEDF mRNA丰度降低有关。比较初产奶牛的不同组织，PEDF mRNA在肝脏中最高，其次是scAT、内脏脂肪组织（AT）和乳腺，在肌肉中最低。初产和经产奶牛中PEDF表达随采样时间的显著变化仅限于AT。我们的数据支持PEDF具有调节作用。PEDF血清浓度及其在scAT中的mRNA丰度的时间进程之间的相似性可能表明，在奶牛中，AT而非肝脏对PEDF具有调节作用。
