Impact of hypoxia stress on the physiological responses of sea cucumber Apostichopus japonicus: respiration, digestion, immunity and oxidative damage

Abstract

Hypoxia is one of the most frequently occurring stressors confronted by industrial cultures of sea cucumber and can cause large economic losses and resource degradation. However, its responsive mechanisms are still lacking. In this paper, the physiological responses of Apostichopus japonicus to oxygen deficiency was illustrated, including induced oxidative response and immune defense and changed digestive enzymes activities. Significantly increased activities of alpha-amylase (AMS), acid phosphatase (ACP), lactate dehydrogenase, catalase, peroxidase, succinate dehydrogenase and higher content of malondialdehyde, and decreased activities of lipase and trypsin (TRY) were observed after hypoxia exposure (dissolved oxygen [DO] 2 mg/L). Expressions of key genes showed that AMS, peptidase, ACP, alkaline phosphatase, lysozyme, heat shock protein 70 and glutathione peroxidase were increased and TRY was decreased under hypoxia. With the decline of the DO level, the decreased tendency of oxygen consumption rates was different in varied weight groups. Moreover, respiratory trees were observed degraded under long-term hypoxia stress, thus leading a negative effect of respiration. These results could help to develop a better understanding of the responsive mechanism of sea cucumber under hypoxia stress and provide a theoretical basis for the prevention of hypoxia risk.

The regulation mechanism of lncRNAs and mRNAs in sea cucumbers under global climate changes: Defense against thermal and hypoxic stresses

“…The thermal stress treatment group (HT) was maintained at a high temperature of 26°C and the thermal and hypoxia combined treatment group (HL) was maintained at a high temperature of 26°C and low dissolved oxygen concentration (2 mg/L). Acclimation was carried out by using a 2-kW heating rod and dissolved oxygen control system, respectively (Huo et al, 2018). Respiratory trees from nine sea cucumber individuals in each group were sampled promptly and preserved in liquid nitrogen, and stored at −80°C.…”

“…Extremely high temperature and low dissolved oxygen would cause thermal stress and hypoxic stress, respectively. These environmental stresses could lead to yield loss and reduce the germplasm quality in the aquaculture industry (Huo et al, 2018). The sea cucumber Apostichopus japonicus is a deposit feeder that participates in carbon cycling in marine ecosystems (Huo et al, 2019b).…”

Air Exposure Affects Physiological Responses, Innate Immunity, Apoptosis and DNA Methylation of Kuruma Shrimp, Marsupenaeus japonicus

“…Air exposure induced significant oxidative and antioxidant responses in L. vannamei (Xu et al, 2018). Other research has detected significant changes in antioxidant enzyme activities in Lithodes santolla (Schvezov et al, 2019), Paralomis granulosa (Romero et al, 2011), Apostichopus japonicus (Huo et al, 2018), Penaeus monodon (Duan et al, 2016b), Babylonia areolate (Liu et al, 2017), and Oryzias melastigma (Cui et al, 2019). Hypoxia exposure had significant effects on the expression profiles of apoptosis and hypoxia-related genes, such as p53, Hif-1α, Hsp70, GSH-Px (glutathione peroxidase) and CAT (catalase) (Xiao, 2015;Sun et al, 2016a;Cai et al, 2018;Ondricek and Thomas, 2018;Camacho-Jiménez et al, 2019).…”

Effects of hypoxia on immune responses and carbohydrate metabolism in the Chinese mitten crab, Eriocheir sinensis

“…Adaptation to the hypoxic conditions would likely have required a large amount of ATP. Increased ACP activity facilitates the hydrolysis of phosphate esters to meet the inorganic phosphoric acid demand required for ATP synthesis (Huo et al, 2018).…”