PECULIARITIES OF LIPID METABOLISM DISRUPTION IN COMMON CARP (CYPRINUS CARPIO L.) EXPOSED TO TOXICANTS OF DIFFERENT CHEMICAL NATURE

Abstract

Modern anthropogenic pressure on aquatic ecosystems leads to increased concentrations of xenobiotics in water bodies, posing a serious ecological threat to aquatic organisms. Phosphate-containing compounds, surfactants, and heavy metals pose a particular danger, as they can interact with each other and enhance the toxic effect. Under these conditions, studying the impact of xenobiotics on biochemical processes in aquatic organisms, particularly on fish lipid metabolism, is highly relevant. Such research provides a deeper understanding of the mechanisms of hydrobiote adaptation to toxic stress and allows for the assessment of the ecological status of water bodies.

Purpose of the work. To elucidate the effects of individual (phosphates, phosphonates, sodium lauryl sulfate) and combined (phosphates and heavy metal salts) xenobiotics on biochemical parameters of the blood and tissues of the scaly carp (Cyprinus carpio) in order to determine the mechanisms of lipid-metabolism disruption under toxic load.

Methodology. The experimental studies were conducted at the Laboratory of Ecological Biochemistry of the T. H. Shevchenko National University “Chernihiv Colehium”. The object of the study was the scaly carp (Cyprinus carpio) weighing 250–300 g. The effects of the following toxicants were assessed: phosphates (7.0 mg/dm³ and 17.5 mg/dm³ corresponding to 2 and 5 MPC), phosphonates (2.28 mg/dm³ and 5.70 mg/dm³ corresponding to 2 and 5 MPC), sodium lauryl sulfate (0.02 mg/dm³ – 2 MPC), and salts of Cu²⁺, Cd²⁺, and Pb²⁺ (2.0 mg/dm³, 0.002 mg/dm³, and 0.02 mg/dm³ respectively, corresponding to 2 MPC). The temperature was maintained at +8…+10 °C to mimic natural conditions. The duration of the experiment was 14 days. Changes in biochemical parameters were determined in the blood, muscles, gills, liver, and brain, including the quantitative content of total lipids, phospholipids, and lipase activity. All results were processed statistically.

Scientific novelty. For the first time, tissue-specific features of lipid metabolism alterations in scaly carp (Cyprinus carpio) under the influence of phosphates, phosphonates, and sodium lauryl sulfate, as well as under the combined action of phosphates and heavy metal salts, were established.

Conclusions. It was established that the studied xenobiotics cause significant alterations in lipid metabolism in the tissues of the scaly carp (Cyprinus carpio), manifested by an increase in lipid concentration in the blood and a decrease in peripheral organs. Phosphates were found to have the most toxic effect, leading to lipid homeostasis disruption, whereas phosphonates and sodium lauryl sulfate exerted milder but systemic effects. The combined action of phosphates with heavy metal salts (particularly Cd²⁺ and Pb²⁺) produced a synergistic effect, resulting in a reduction of phospholipid content and inhibition of lipase activity. The gills, liver, and brain were found to be the most sensitive to toxic exposure, indicating the high reactivity of these tissues and the key role of the liver and gills in detoxification processes. The obtained results may be useful for ecotoxicological assessment of aquatic ecosystems contaminated with toxicants.