Prostaglandin Actions in Established Insect Cell Lines

Authors: LI, YAO-FA - Hebei Academy Of Agriculture & Forestry; Goodman, Cynthia; ZHOU, KAILE - University Of Missouri System; Ringbauer, Joseph - Joe; Reall, Tamra; Stanley, David

Submitted to: In Vitro Cellular and Developmental Biology - Animal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2017
Publication Date: 4/28/2017
Citation: .Li, Y., Goodman, C.L., Zhou, K., Ringbauer Jr, J.A., Reall, T., Stanley, D.W. 2017. Prostaglandin Actions in Established Insect Cell Lines. In Vitro Cellular and Developmental Biology - Animals. 53:451-429. https://doi.org/10.1007/s11626-017-0147-0.
DOI: https://doi.org/10.1007/s11626-017-0147-0

Interpretive Summary: Insect pests are responsible for tremendous reductions in crop production, via the direct feeding damage and also by carrying plant disease organisms to crop plants. We are working to address this problem by creating new insect management technologies. In our efforts to increase the efficiency of our research, we have established new, continuously growing insect cell lines as our main research tool. These cell lines are low cost, effective research tools. In this paper we discovered the actions of prostaglandins, which mediate inflammation in humans, in three insect cell lines. In higher concentrations, the prostaglandins are harmful to the insect cells. Treating the cells with inhibitors of prostaglandin production, the same inhibitors humans consume to relieve inflammation, is also harmful. We find the insect cells require optimal, regular production of prostglandins which are responsible for maintaining normal cell functions. This information will be used by scientists working to apply growing knowledge of insect cell lines to the overall goal of creating new insect pest management technologies and ultimately to consumers of healthy crop products.

Technical Abstract: Prostaglandins (PGs) are oxygenated metabolites of arachidonic acid (AA) and two other C20 polyunsaturated fatty acids that serve as biochemical signals that mediate a wide range of physiological functions in animal cells. For example, PGs influence protein expression in establish insect cell lines and they mediate several insect immune functions. We investigated the influence of PGs and pharmaceutical inhibitors of PG biosynthesis on cell lines established from three insect orders, the squash bug, Anasa tristis (AtE15A cells; Hemiptera), the red flour beetle, Tribolium castaneum (TcA-CLG1 cells; Coleoptera), and the tobacco budworm, Heliothis verescens (HvAM1 cells; Lepidoptera). Treating the insect cell lines with PGA1, PGA2 or PGD2 led to dose-dependent reductions in cell numbers. All three cell lines were sensitive to PGA1 and PGA2 treatments with IC50 values ranging from 9.9 to 26.9 'M and were less sensitive to PGD2 treatments with IC50 values of 31.6 to 104.7 'M. PGE1, PGE2 and PGF2' treatments did not influence AtE15A or HvAM1 cell numbers at lower concentrations, but led to dose-related reductions in TcA-GLC1 cells. Similar treatments with pharmaceutical inhibitors of PG biosynthesis also led to reduced cell numbers. MAFP (inhibits phospholipase A2, the first step in PG biosynthesis), indomethacin (inhibits PG biosynthesis) and esculetin (inhibits lipoxygenase, blocks synthesis of leukotrienes and other AA metabolites). Because these compounds are used to relieve inflammation and other medical issues in human and veterinary medicine, they are not toxic to animal cells. We infer PGs are necessary in optimal quantities for on-going homeostatic functions in established cell lines. In quantities above (by exogenous treatments) and below (by inhibiting their synthesis) the optima they are deleterious.