Page 25 - 《渔业研究》2026年第2期

168 渔 业 研 究 第 48 卷

Effects of acute hypoxia stress and reoxygenation on antioxidant and apoptosis
in gill tissue of pike perch (Sander lucioperca)

1
YUAN Xiaole ，LIAN Zongqiang 2,3,4 ，LIU Yanbin 2,3,4 ，LIU Kai 2,3,4 ，XIAO Wei 2,3,4 ，
1
1
SAI Qingyun 2,3,4 ，WANG Yan 2,3,4 ，ZHAO Wenkai ，LI Xiaojun ，LI Lanlan 1*
(1. College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China;
2. Ningxia Fisheries Research Institute, Yinchuan 750001, China;
3. Ningxia Fishery Engineering Technology Research Center, Yinchuan 750001, China;
4. Academician Work Station of Ningxia Fishery Science and Technology, Yinchuan 750001, China)

Abstract: [Background] In recent years, factors such as extreme climate, high-density aquaculture and water
eutrophication have led to increased fluctuations in dissolved oxygen concentration in water, consequently hyp-
oxia in aquatic animals has become more frequent. Pike perch (Sander lucioperca) is an economically import-
ant fish species and highly sensitive to hypoxic conditions. [Objective] This study aims to investigate the ef-
fects of hypoxic stress on the gill tissue structure, antioxidant capacity and gene expression of S. lucioperca.
[Methods] Acute hypoxic stress (0, 6, 48 h) and reoxygenation (6 h) experiments were conducted to analyze
the structural changes, oxidative stress status and gene expression differences of gill tissues in S. lucioperca.
[Results] Hypoxic stress resulted in significant damage to the structure of S. lucioperca gill lamellae. It also
significantly increased (P<0.05) the activities of antioxidant enzymes (SOD, CAT, GSH-Px), and the mRNA ex-
pression of pro-apoptotic genes (Bax, Caspase3), while significantly decreasing (P<0.05) in the mRNA expres-
sion of anti-apoptotic genes (Bcl-2). The mRNA expression of Egln-2, a gene encoding prolyl hydroxylase, first
decreased and then increased, while the mRNA expression of Hif-1a, a key factor of the hypoxia signalling
pathway, first increased and then decreased. After reoxygenation, the gill tissue structure and related indexes re-
covered but did not fully reach the level of the control group. [Conclusion] Hypoxic stress significantly altered
physiological and biochemical indicators as well as gill lamellae morphology in S. lucioperca, while short-term
reoxygenation (6 h) markedly alleviated hypoxic stress responses. [Significance] The study could provide
baseline data for further elucidation of the regulatory mechanism of hypoxic stress in S. lucioperca.
Key words: Sander lucioperca; hypoxic stress; gill tissue; oxidative stress; apoptosis