Angiotensin II type 2 receptors facilitate reinnervation of phenol-lesioned vascular calcitonin gene-related peptide (CGRP)-containing nerves in rat mesenteric arteries

The present study was designed to investigate involvement of angiotensin (Ang) II type 2 receptors (AT2 receptors) in restoration of perivascular nerve innervation injured by topical phenol treatment. Male Wistar rats underwent in vivo topical application of 10% phenol around the superior mesenteric artery. After phenol treatment, animals were subjected to immunohistochemistry of the third branch of small arteries, Western blot analysis of AT2 receptor protein expression in dorsal root ganglia (DRG) and studies of mesenteric neurogenic vasoresponsiveness. Ang II (750 ng/kg/day), nerve growth factor (NGF; 20 μg/kg/day) and PD123,319 (AT2 receptor antagonist; 10 mg/kg/day) were intraperitoneally administered for 7 days using osmotic mini-pumps immediately after topical phenol treatment. Losartan (AT1 receptor antagonist) was administered in drinking water (0.025%). Phenol treatment markedly reduced densities of both calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI)- and neuropeptide Y (NPY)-LI-containing fibers. NGF restored densities of both nerve fibers to the Sham control level. Coadministration of Ang II and losartan significantly increased the density of CGRP-LI-fibers but not NPY-LI-fibers compared with saline control. The increase of the density of CGRP-LI-fibers by coadministration of Ang II and losartan was suppressed by adding PD123,319. Coadministration of Ang II and losartan ameliorated reduction of CGRP nerve-mediated vasodilation of perfused mesenteric arteries caused by phenol treatment. The AT2 receptor protein expression detected in DRG was markedly increased by NGF. These results suggest that selective stimulation of AT2 receptors by Ang II facilitates reinnervation of mesenteric perivascular CGRP-containing nerves injured by topical phenol application in the rat.</p

Degradation of STK16 via KCTD17 with Ubiquitin&ndash;Proteasome System in Relation to Sleep&ndash;Wake Cycle

Serine/threonine-protein kinase 16 (STK16) is a novel member of the Numb-associated family of protein kinases with an atypical kinase domain. In this study, we aimed to investigate the involvement of STK16 in sleep&ndash;wake mechanisms. We confirmed the expression of Stk16 in the murine hypothalamus, the sleep&ndash;wake center, and found considerable changes in STK16 protein levels in the anterior hypothalamus during the light&ndash;dark cycle. We found that the coexistence of the potassium channel tetramerization domain containing 17 (KCTD17), an STK16 interactor, caused STK16 degradation. In contrast, the proteasome inhibitor MG132 inhibited the degradation of STK16. In addition, polyubiquitinated STK16 was observed, suggesting that KCTD17 acts as an adapter for E3 ligase to recognize STK16 as a substrate, leading to STK16 degradation via the ubiquitin&ndash;proteasome system. The vast changes in STK16 in the anterior hypothalamus, a mammalian sleep center, as well as the reported sleep abnormalities in the ubiquitin B knockout mice and the Drosophila with the inhibition of the KCTD17 homolog or its E3 ligase cullin-3, suggest that STK16 plays a major role in sleep&ndash;wake regulation

IL17A Suppresses <i>IGFBP1</i> in Human Endometrial Stromal Cells

Interleukin (IL) 17A has been implicated in preeclampsia, preterm labor, and miscarriage. IL17A production in non-lymphoid tissues is mainly carried out by unconventional γδ17T cells. Innate lymphoid cells (ILCs) 3, a subgroup of innate lymphocytes, can also be a source of IL17A in the endometrium and are required from implantation to early pregnancy, with their regulation ensuring that pregnancy continues. Herein, we examined the expression of γδ17T cells and ILC3 regulators IL1B, IL23A, and IL17D and IL17A receptors (IL17RA/IL17RC) in human endometrial stromal cells (EnSCs) and cell lines (KC02-44D). Accordingly, quantitative polymerase chain reaction and immunoblotting were employed. IL1B, IL23A, and IL17D were significantly upregulated in decidualized EnSCs and KC02-44D cells. A significant augmentation in IL17RA/IL17RC was also observed in decidualization. IL17A stimulation of KC02-44D cells during decidualization suppressed the decidualization marker IGFBP1. The involvement of transcription factor Forkhead box protein O1 (FOXO1) in this repression was reflected by its translocation from the nucleus into the cytoplasm. A role for IkB kinase alpha in FOXO1 phosphorylation-mediated migration was also suggested. Taken together, our findings indicate that the secretion of IL17A by γδ17T and ILC3 cells in the uterus contributes to EnSCs function and may play critical roles in regulating IGFBP1-mediated implantation and fetal growth

エルゴチオネインによる脱落膜化制御機構

ヒト子宮内膜では、卵巣からのステロイドホルモンの影響を受けて、周期的な増殖、分泌性の変化、間質の脱落膜化、ならびに剥離（月経）が起こる。排卵後の黄体から分泌されるプロゲステロンを受けて、子宮内膜に含まれる間質細胞は脱落膜化し、胚着床のための環境を整える。この脱落膜化に異常が生じることで、着床障害や流産、妊娠高血圧腎症、胎児発育不全、癒着胎盤などが起こる。われわれは過去に脱落膜化ヒト子宮内膜間質細胞における機能性食品エルゴチオネインのトランスポーターOCTN1 の発現上昇を見出しており、本研究において脱落膜化へのエルゴチオネインの効果を検討した。エルゴチオネイン によってヒト子宮内膜間質細胞株での脱落膜化のマーカーであり、かつ絨毛外栄養膜細胞に働きかけることで胎盤形成にも関与するIGFBP1 の発現上昇が抑制されることを見出した。さらに、この抑制には転写制御因子FOXO1 の減少が関与することも見出した。エルゴチオネインはOCTN1 を介し、胎盤形成を促すIGFBP1 の発現を抑制することで、癒着胎盤等を予防している可能性が示唆された。identifier:http://reposit.sun.ac.jp/dspace/handle/10561/202

ヒト子宮内膜間質細胞の脱落膜化ならびに 老化モデルの作製

ヒトにおいて胚が着床するためには、子宮内膜に含まれる間質細胞が着床に先んじて脱落膜化する必要がある。実験動物においては胚着床後にのみ脱落膜化が開始されるため、ヒトの脱落膜化の研究を行う際に実験動物は適さない。そのため、脱落膜化の研究はヒト子宮内膜組織より単離された初代培養ヒト子宮内膜間質細胞を用いて研究が行われてきた。本研究ではヒト子宮内膜間質細胞株である KC02-44D 細胞に対して細胞膜透過性の 8-Bromo-cAMP を用いることで脱落膜化に要する時間を短縮したモデルを作製し、その後の脱分化も確認した。さらに酸化ストレスによる老化モデルを作製した。老化モデルでは脱落膜化マーカーの発現に変化は生じなかった。一方で、老化モデルは炎症性サイトカインを含む細胞老化関連分泌形質の産生・分泌が亢進しており、分泌された細胞老化関連分泌形質が周りの細胞の脱落膜化や胚着床に何らかの影響を与えている可能性が示唆された。identifier:http://reposit.sun.ac.jp/dspace/handle/10561/202