Prostaglandin E2(PGE2) is an autocrine and paracrine signal in insects and other animals. Its signal pathways in target cells are well understood in mammalian system but not in insects. Here, we assessed PGE2 signaling in hemocytes of Spodoptera exigua through knocking-down of signal component genes by RNA interference (RNAi) and knocking-out (KO) of PGE2 receptor using CRISPR-Cas9. From S. exigua transcriptome, we selected hemocyte signaling components and analyzed their functions in cellular immune responses through RNAi. KO mutant against PGE2 receptor exhibited severely hampered larval development and adult fecundity.

생강은 다양한 생리활성이 확인됨에 따라 여러나라에서 전통의약재로서 폭넓게 사용되고 있다. 하지만 진저롤 및 그 유도체에서 유래되는 자극적인 향미로 인하여 식품소재로서의 사용에는 다소 어려움이 있는 실정이다. 본 연구에서는 생강을 Lactobacillus plantarum, Leuconostoc mesenteroides, Streptococcus thermophilus, 및 Lactobacillus acidophilus 등과 같은 유산균에 의한 발효를 통하여 생강의 관능특성을 증진시키려 하였다. 발효된 생강은 in vitro에서 전자공여능 및 cyclooxygenase-2 저해활성을 나타내었으며 또한 산화질소의 생성도 억제하였다. 특히 김치유래 유산균으로 발효한 생강추출물인 GLPe와 GLMe는 Raw 264.7 macrophages에서 prostaglandin-E2 의 생성을 60% 이상 저해하였으며 15-lipoxygenase에 대한 저해 활성도 나타내었다. 따라서 GLPe나 GLMe와 같은 발효생강 추출물은 섭취할 때 자극적인 향미로 인한 거부감이 적으며 염증이나 앨러지 등에 의해 야기되는 바람직하지 않은 증상을 일부 완화시킬 수 있는 건강식품소재로서 사용될 수 있음을 알 수 있었다.

Prostaglandins (PGs) are critical lipid mediators involved in many reproductive processes including luteolysis, maternal recognition of pregnancy, and implantation in domestic animals. In pigs, PGs, especially PGE2 and PGF2α, are produced in the uterine endometrium. The actions of PGE2 and PGF2α are mediated by signaling receptors, PTGERs and PTGFR, respectively, but their expression in the uterine endometrium is not well elucidated. In this study, we determined expression of PTGERs and PTGFR in the uterine endometrium during the estrous cycle and pregnancy in pigs. Uterine endometrial tissue samples were collected from Day (D) 12 and D15 of the estrous cycle and from D12, D15, D30, D60, D90, and D114 of pregnancy. Temporal expression of all genes studied was analyzed by real-time RT-PCR. PTGERs except for PTGER1 were expressed in the uterine endometrium during the estrous cycle and pregnancy. Levels of PTGER2 and PTGER3 mRNA increased during early pregnancy and late pregnancy, respectively, and levels of PTGER4 mRNA were not changed during pregnancy. Levels of PTGFR mRNA were highest on D90 of pregnancy. Results of this study showed that expression of PG receptors was dynamically regulated in the uterine endometrium during pregnancy in pigs. These results indicate that actions of PGs are dependent on types of receptors and is critical to support the establishment and maintenance of pregnancy at the maternal-fetal interface in pigs.

Sodium-potassium-chloride co-transporter (NKCC) is a membrane bound channel protein that plays a prominent role in a variety of epithelial absorptive, secretory processes and a direct role in cell volume regulation, in which NKCC transports sodium, potassium, and chloride ions across the cell membrane. It has been known that prostaglandin E2 (PGE2) induces an acute cell lysis of specific hemocyte type, oenocytoid, to release prophenoloxidase into the plasma and ouabain (a specific sodium pump inhibitor) inhibits the oenocytoid cell lysis resulting in preventing phenoloxidase activation. However, it is not clear how the intracellular signaling pathway leads to oenocytoid cell lysis in response to PGE2. This study was designed to analyze functional role of NKCC in the cell lysis to release prophenoloxidase. A gene structure of NKCC was derived from cDNA library of Spodoptera exigua hemocyte, NKCC was expressed in all developmental stages and tissues. A real time quantitative RT-PCR showed that bacterial challenge significantly induced its expression. Specific inhibitors of NKCC, bumetanide and chlorothiazide, clearly prevented the cell lysis in a dose dependent manner. When RNA interference using double stranded RNA (dsRNA) specific to NKCC suppressed its expression, the oenocytoid lysis and PO activation was significantly inhibited in response to PGE2. It also reduced nodule formation to bacterial challenge. These results indicate that NKCC is associated with oenocytoid cell lysis probably by increasing cell volume through inward transport of ions in response to PGE2.

Prostaglandin (PG) E2 is an important mediator of skin wound healing without excessive scarring and gastric ulcer healing. However, PGE2 has a short lifetime in vivo because it is metabolized rapidly by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). Ethanol extract of Eriobotryae folium (EFEE) elevated intracellular and extracellular PGE2 levels in HaCaT cells and inhibited 15-PGDH (ED50 : 168.4μg/mL) with relatively low cytotoxicity (IC50 : 250.0μg/mL). Real-time PCR analysis showed that mRNA expression of cyclooxygenase (COX)-1 and COX-2 enzymes were increased and prostaglandin transporter (PGT) was decreased in HaCaT cells by EFEE. Moreover, wound healing effect of EFEE (168.4μg/mL) was comparable to that of TGF-β1 (300 pg/mL) as a positive control. These results demonstrate that EFEE may be valuable therapeutic materials for the treatment of PGE2 level dependent diseases.