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Abstract

In this study antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHpx), glutathione reductase (GR) and glutathione S-transferase (GST) were investigated in unfertilized and fertilized eggs, 12, 22 and 32 day embryos of rainbow trout Oncorhynchus mykiss (Walbaum 1792). Vitamin E, lipid peroxidation products and fatty acids levels were also determined. A significant decrease in vitamin E level was found in fertilized eggs of O. mykiss. In contrast, the level of malondialdehyde (MDA) was very high in fertilised eggs and 12 day embryo. The PUFA contents in fertilized eggs and 12 day embryo were found to be lower than in the other embryonic stages. Measurable amounts of all the SOD, CAT, GSHpx, GR and GST enzymes activities were present in O. mykiss eggs and embryos. The most intense decrease was detected in the activities of SOD, GR and GST in fertilized eggs, whereas the most intense increase in the CAT activity was detected in the same stage of O. mykiss. GSHpx activity showed a significant increase in fertilized eggs and in 32 day embryos before hatching. GST activity showed the most significant increase in 22 day embryos of eyed eggs stage.

Superoxide Dismutase Multigene Family from a Primitive Chondrostean Sturgeon, Acipenser baerii: Molecular Characterization, Evolution, and Antioxidant Defense during Development and Pathogen Infection

“…Sturgeon, like most other fish species, exhibit oviparity in their embryonic development, implying that fertilized embryos develop their antioxidant defense systems independently of parental contribution during their early development. Several previous studies have proposed important roles for SOD in the development of fish embryos, including different teleost species-Salmo iridiaeus [29], Oncorhynchus mykiss [30], Scophthalmus maximus [89], Lates calcarifer [90], Oryzias latipes [91], and Austrofundulus limnaeus [32]-as well as sturgeon species: A. gueldenstaedtii and A. naccarii [31,44]. These studies suggest that the AOE system is finely regulated in response to changes in the oxidative stress status during early development, including from cell proliferation and specific signaling for organogenesis, although the specific temporal patterns are little generalized due to species-specific differences.…”

“…Fish employ three different SOD isoforms that are characterized by their metal cofactors and cellular localization: copper/zinc SOD, present in the cytosol (Cu/Zn-SOD; SOD1); manganese SOD, located within mitochondria (Mn-SOD; SOD2); and extracellular Cu/Zn-SOD, predominantly localized within the extracellular matrices of tissues (EC-SOD; SOD3) [9,20,21]. Several biochemical and molecular studies have shown that fish SODs are modulated by their lifecycles, including embryonic and larval development, as well as exposure to environmental stresses, including endotoxins and pathogenic infections, suggesting that fish SODs play crucial roles not only in the development but also in the maintenance of a homeostatic balance between the innate immune response and antioxidant defenses [22][23][24][25][26][27][28][29][30][31][32][33]. However, most studies on fish SODs have been limited to enzymatic measurements, which represent total or pooled SOD activity without distinguishing among the three SOD isoforms, and to transcriptional modulation, which is only representative of one or two distinct fish SODs.…”

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“…The increased catabolism is much higher during yolk-sac development than embryogenesis, probably due to the increased activity and the resultant higher energy requirements following hatch (Gunasekera et al, 2001;Johnston et al, 2007;Zengin et al, 2013;2015). Tocher (2010) reported that in general, lipid utilization occurs to a greater extent after hatching, possibly reflecting the greater energy demands of the mobile, freeswimming yolk-sac larvae when compared with the embryonic egg stages.…”

“…Experimental fish and sample collection was described in our previous study (Zengin et al, 2015). The O. mykiss used were obtained from the local and commercial fish farm Yeşilova in Zara (SivasTurkey).…”

“…Consequently, the understanding of antioxidant enzyme dynamics could provide an important contribution for the enhancement of larval and juvenile quality. Previously we showed the correlation between antioxidant enzyme activities and lipid peroxidation during embryogenesis of rainbow trout Oncorhynchus mykiss (Zengin et al, 2015). The overall aim is the characterization of the antioxidant systems in cultured yolk-sac larvae of Oncorhynchus mykiss in order to enhance the growth and quality of early life stages by avoiding oxidation problems that may cause pathologies and diseases.…”