Antioxidants and molecular damage in Nile Tilapia (Oreochromis niloticus) after exposure to microplastics

Abstract

Recently, research on the biological effects of microplastics (MPs) has grown exponentially. However, effects of MPs on freshwater fishes and the mechanisms of the biological effects of MPs were limited. So, the purpose of the current study was to clarify the effects of microplastics on oxidative stress response, DNA fragmentation, and proteinogram of the early juvenile stage of Nile Tilapia (Oreochromis niloticus). The fishes were assigned into four groups: one control, three MPs-exposed groups as 1 mg/L of MPs, 10 mg/L of MPs, and 100 mg/L of MPs respectively for 15 days and 15 days of recovery. The activities of superoxide dismutase, catalase, total peroxides, and oxidative stress index (OSI), as well as lipid peroxidation and DNA fragmentation, increased in groups exposed to MPs compared to the control group in a dose-dependent manner. In contrast, the activity of total antioxidant capacity decreased in groups exposed to MPs compared to the control group in a dose-dependent manner. The electrophoretic pattern of muscle proteins revealed alteration in the proteinogram in the MPs-exposed groups compared to control. After the recovery period, the activities of superoxide dismutase, catalase, total peroxides, total antioxidant capacity, lipid peroxidation, DNA fragmentation, and the electrophoretic pattern of muscle proteins returned to normal levels in 1 mg/L of MPs-exposed group. Combined with our previous work, these results suggest that MPs cause the overproduction of reactive oxygen species (ROS) and alters the antioxidants parameters, resulting in oxidative stress and DNA damage. The present study fosters a better understanding of the toxic effects of MPs on Tilapia as a freshwater model.

The effects of four plant extracts on growth, sex reversal, immunological and haemato‐biochemical parameters in Nile tilapia,Oreochmomis niloticus(Linnaeus, 1758)

“…On the other hand, MT exposure was found not to alter CAT activity in zebrafish embryo (Rivero‐Wendt et al., 2016). Significant increase in plasma SOD and CAT activities, as observed in the present study, was reported in O. niloticus exposed to microplastics (Hamed et al., 2020). All four plant extract‐fortified diets lowered SOD values compared with control indicating their antioxidant and tissue protective potential.…”

Microplastics-Induced Eryptosis and Poikilocytosis in Early-Juvenile Nile Tilapia (Oreochromis niloticus)

“…For example, Yirong et al ( 2020 ) found that di (2-ethylhexyl) phthalate can induce apoptosis by stimulating an oxidative burst of neutrophils in carp ( Cyprinus carpio ). This apoptosis was explained by Walpitagama et al ( 2019 ), who supported the assumptions of reactive oxygen species (ROS)–prompted apoptosis demonstrated in our previous study (Hamed et al, 2020 ). In addition, polystyrene upregulated the expression levels of pro-apoptotic proteins, which are strictly linked to the commencement of cell apoptosis (Xu et al, 2019 ; Yirong et al, 2020 ).…”

“…Strunjak-Perovic et al ( 2009 ) reported that the nuclear anomalies may result from gene mutations in the nuclear lamina of the nucleus. Moreover, da Costa Araújo et al ( 2020a ) found that the genotoxicity of polyethylene MPs on erythrocytes was indirectly induced by the formation of free radicals that interfere with DNA integrity, and our previous study linking oxidative stress in tilapia with exposure to MPs (Hamed et al, 2020 ) reinforces this conclusion. On the contrary, no significant differences between PVC and Mater-Bi micro-debris–exposed groups and the control group were found in Dreissena polymorpha Mn (Magni et al, 2020 ).…”

“…The toxic effects of MPs on the aquatic organisms are debatable and differ across the species according to the size and type of MPs as well as the presence of heavy metals and pesticides (Rainieri et al, 2018 ; Wu et al, 2019 ). In fish, several adverse effects, include diminished predatory prowess, endocrine inhibition, oxidative stress, hepatic stress, and intestinal alterations (Rochman et al, 2013 ; Ferreira et al, 2016 ; Pedà et al, 2016 ; Hamed et al, 2019a , 2020 ). Although there are many pieces of research on the MPs effects on fish, still, there is not enough information on the effect of MPs on the alterations of blood cells and molecular damage especially on the Nile tilapia ( Oreochromis niloticus ) (Hamed et al, 2019a , 2020 ).…”

Microplastics Contamination in the Environment: An Ecotoxicological Concern

“…There was no oxidative stress and histological changes, however, induced behavioral abnormalities such as hyperactive swimming in the fish (Chen et al, 2020). On contrary, microplastics caused the overproduction of reactive oxygen species and alterations in the antioxidants parameters resulting in oxidative stress and DNA damage in Nile tilapia Oreochromis niloticus (Hamed et al, 2020). Polyvinyl microplastics when exposed through diet induced oxidative stress and hepatic damage in Clarias gariepinus (Iheanacho and Odo 2020a), and caused variations in hematology, antioxidant enzymes, lipid peroxidation, and acetylcholinesterase activity in African catfish Clarias gariepinus (Iheanacho and Odo, 2020b).…”