Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, 10-748 Olsztyn, Poland.
The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jabłonna, Poland.
Int J Mol Sci. 2020 Oct 15;21(20):7647. doi: 10.3390/ijms21207647.
The ovine choroid plexus (ChP) expresses the long isoform of the leptin receptor, which makes this structure a potential target for leptin action. In sheep, leptin concentration in plasma is higher during long days (LD) than short days (SD). This study evaluates the influence a of photoperiod on leptin impact on the gene expression of Toll-like receptor 4 (), proinflammatory cytokines (, ), their receptors (, , , , ) and inflammasome components necessary for pro-IL-1β activation (, , ), chemokine (), leptin receptor isoforms (, ) and a suppressor of cytokine signalling () in the ChP of ewes treated or not with lipopolysaccharide (LPS). Studies were conducted on adult female sheep divided into four groups ( = 6 in each): control, leptin (20 μg/kg), LPS (400 ng/kg), and LPS and leptin injected under SD and LD photoperiods. The leptin alone did not affect the gene expression but in co-treatment with LPS increased ( < 0.05) IL1B but only during SD, and , , , and only during LD, and decreased ( < 0.05) the expression only during SD photoperiod. This indicates that the immunomodulatory action of leptin on the ChP is manifested only under the LPS challenge and is photoperiodically dependent.
绵羊脉络丛（ChP）表达瘦素受体的长异构体，这使得该结构成为瘦素作用的潜在靶点。在绵羊中，长日照（LD）期间血浆中的瘦素浓度高于短日照（SD）。本研究评估了光周期对瘦素对 LPS 处理或未处理的绵羊脉络丛中 Toll 样受体 4（）、促炎细胞因子（、）、其受体（、、、、）和促 IL-1β 激活所需的炎症小体成分（、、）、趋化因子（）、瘦素受体异构体（、）和细胞因子信号转导抑制物（）基因表达的影响（）。研究在成年雌性绵羊中进行，分为四组（每组 6 只）：对照组、瘦素（20 μg/kg）、LPS（400 ng/kg）和 LPS 和瘦素在 SD 和 LD 光周期下注射。单独的瘦素不会影响基因表达，但与 LPS 共同处理时会增加（<0.05）IL1B，但仅在 SD 期间，和、和仅在 LD 期间，和降低（<0.05）仅在 SD 光周期期间的表达。这表明瘦素对 ChP 的免疫调节作用仅在 LPS 挑战下表现出来，并且依赖于光周期。
