Glutathione peroxidase 4 knock-down triggers ferroptosis in Penaeus vannamei hepatopancreas during hypoxia and reoxygenation.

The white shrimp Penaeus vannamei during its life cycle are commonly exposed to environmental stressors including hypoxia and reoxygenation that can affect their growth and survival. Hypoxia inducible Factor-1 (HIF-1) is a very important transcription factor involved in the responses to hypoxia and participates in other processes, including ferroptosis. Glutathione peroxidase 4 (GPx4) is a key ferroptosis component. In mammals, GPx4 has important biological functions beyond its antioxidant role. We studied the changes of HIF-1α and the ferroptosis process components, heme oxygenase -1 (HO-1), acyl-CoA synthetase long chain family member 4 (ACSL4), and catalase (CAT) in GPx4 knock-down shrimp exposed to hypoxia and reoxygenation. Malondialdehyde (MDA) content and CAT activity were also evaluated. Changes in HIF-1α, CAT, ACSL4, and HO-1 expression occurred 6 and 12 h after hypoxia and reoxygenation in shrimp hepatopancreas. HIF-1α and CAT expression were reduced during hypoxia and reestablished in reoxygenation at 6 and 12 h, while HO-1 did not change at 6 h, but increased during hypoxia at 12 h. Also, ACSL4 expression decreased during hypoxia and reoxygenation at 12 h, while MDA content was not affected by hypoxia and reoxygenation. GPx4 knock-down increased ACSL4 expression, MDA content, and CAT activity indicating that the ferroptosis process is induced by the intrinsic pathway in hepatopancreas during GPx4 knock-down.