Prostaglandin A2 induces apoptosis in three cell lines derived from the fall armyworm, Spodoptera frugiperda

Authors: WANG, YONG - Shenyang Agricultural University; Goodman, Cynthia; Ringbauer, Joseph - Joe; LI, YAOFA - Hebei Academy Of Agriculture & Forestry; Stanley, David

Submitted to: Archives of Insect Biochemistry and Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/31/2021
Publication Date: 9/13/2021
Publication URL: https://handle.nal.usda.gov/10113/7534801
Citation: Wang, Y., Goodman, C.L., Ringbauer Jr, J.A., Li, Y., Stanley, D.W. 2021. Prostaglandin A2 induces apoptosis in three cell lines derived from the fall armyworm, Spodoptera frugiperda. Archives of Insect Biochemistry and Physiology. 108(3). Article 21844. https://doi.org/10.1002/arch.21844.
DOI: https://doi.org/10.1002/arch.21844

Interpretive Summary: Chemical insecticides are effective pest insect management tools, however, negative effects, including environmental contamination and insect resistance to the insecticides attend use of these products. These negative effects drive research into alternative insect management technologies such as disrupting development of juvenile insects. The problem is that many biochemical signaling mechanisms that influence development are not fully understood. Here, we report discovery of a signaling system that helps drive insect development. This system contributes to regulating the proper number of cells in the body. In the absence of the regulation, insects cannot develop into functional adults. Here, we report on the properties of the signaling system. Inhibiting the system with a specific drug or silencing a gene that encodes a component of the system led to reduced control of development. This new information will be used by scientists at the international level to improve understanding of developmental processes in pest insects. This information will ultimately lead to improved insect pest management technologies, which will reduce costs of managing insect pests and hence lead to high quality foods at reduced costs to consumers.

Technical Abstract: Animals maintain homeostasis of cell numbers, constantly creating new cells and eliminating others. Programmed cell death, apoptosis, is one mechanism of cell elimination and it acts in many aspects of animal biology. Drawing on the biomedical background, several signals launch the apoptosis mechanisms, including prostaglandins (PGs). Based on this information, we posed the hypothesis that PGs similarly induce apoptosis in insect cell lines. We used three Spodoptera frugiperda cell lines, including two newly established, BCIRL-SfNS-0518B-YL derived from central nervous system (SfNS) and BCIRL-Sf4FB-0614-SGS derived from fat body (SfFB), and the commercially available Sf9 cells. Using kinetic apoptosis kit, we found treating SfNS cells for 18 h with 15 or 20 'M PGA2 led to decreases in cell numbers, coupled with increased numbers of apoptotic and dead cells. Similar exposures to 10 'M PGA2 (24 h) led to substantial increases in apoptotic cells, confirmed by TUNEL assay on a flow cytometer. The influence of PGA2 treatments increased with dosage, as we recorded about 20% apoptosis at 24 h post-PGA2 treatments (10 'M) and about 34% apoptosis at 24 h post-30 'M treatments. PGA2 treatments led to 10- to 30-fold increases in mRNAs encoding apoptosis-specific caspases-1, -2, -3, & -5 at 12 h and 40- to 60-fold increases in mRNAs encoding caspases-1 and -2, 10-fold increases for caspases-3 and -5 at 24 h. These findings strongly support our hypothesis that PGs induce apoptosis in an insect cell line and confirm an additional PG action in insect biology.