In vivo changes in carbonic anhydrase activity and histopathology of gill and liver tissues after acute exposure to chlorpyrifos in rainbow trout

Abstract

Chlorpyrifos is an organophosphate pesticide widely used in agriculture and aquaculture. This study investigated its effects on carbonic anhydrase (CA) enzyme activity and histopathology of rainbow trout gill and liver. The fish were exposed to 2.25 (25 % of 96 h LC 50 ), 4.5 (50 % of 96 h LC 50 ), and 6.75 µg L -1 (75 % of 96 h LC 50 ) of chlorpyrifos for 24, 48, 72, and 96 h. CA activity was measured in liver and gills and histopathological changes were examined by light microscopy. The most common liver changes at most of the chlorpyrifos concentrations were hyperaemia and degenerative changes. Gill tissues were characterised by lamellar hyperaemia, lamellar oedemas, clumping, cellular degeneration, hyperplasia, and lamellar atrophy. CA enzyme activity in the gills decreased at all concentrations at 48, 72, and 96 h after exposure to chlorpyrifos (p<0.05). Similarly, there was a time-dependent decrease in CA activity at all of the concentrations in liver tissues (p<0.05). The present study indicated that chlorpyrifos inhibits CA enzyme activity and causes histopathological damage in gill and liver tissues.

Adverse effects of organophosphorus pesticides on the liver: a brief summary of four decades of research

“…This decline may be related to changes in the inner mitochondrial membrane permeability caused by lipid peroxidation. A time-dependent decrease in carbonic anhydrase activity was reported in fish exposed to chlorpyrifos (35). Carbonic anhydrase in hepatocyte mitochondria plays a vital role in the regulation of ionic balance, which is required in metabolic reactions, production of ATP, and transport processes (102).…”

“…OPs are oxidants and impair enzymatic antioxidant defences, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST) (23,34,44,(114)(115)(116)(117)(118)(119)(120)(121)(122)(123)(124)(125)(126)(127)(128)(129). Malathion, methyl parathion, and parathion in HepG2 cell lines, as well as chlorpyrifos, methidathion, chlorfenvinphos, and dimethoate in rat liver and diazinon in fish most probably disrupt membrane lipids through oxidative stress (23,35,61,116,118,(130)(131)(132)(133)(134)(135). Table 1 summarises the key changes in antioxidant defence and oxidative stress biomarkers caused by OPs.…”

“…An excessive amount of liver blood and degenerative changes were found in the liver of fish exposed to chlorpyrifos through contaminated water (35).…”

In vivo effects of Aphanizomenon flos-aquae DC-1 aphantoxins on gas exchange and ion equilibrium in the zebrafish gill

“…Carbonic anhydrase is a zinc metalloenzyme having an important role in the removal and exchange of CO 2 between the blood and tissues in fish, and is also responsible for catalyzing the reversible hydration/dehydration of CO 2 to form bicarbonate and protons (Esbaugh and Tufts, 2006). Several previous studies have reported decreases in gill CA activity as a result of exposure to toxicants (Ceyhun et al, 2010;Topal et al, 2014;Ali et al, 2015). However, no studies investigating the impacts of cyanobacterial neurotoxins or PSPs on CA activity in the gills of fish have been published.…”

“…Therefore, alterations in branchial physiological function may serve as crucial biomarkers of exposure to environmental challenges (Brunelli et al, 2011). Alterations in gill ultrastructure, reactive oxygen species (ROS), total antioxidative capacity (T-AOC), and the activities of carbonic anhydrase (CA), Na + -K + -ATPase (NKA), and lactate dehydrogenase (LDH) are sensitive and valuable parameters that can be used to assess the impacts of exposure to many anthropogenic or natural pollutants (Pandey et al, 2008;Shimomura et al, 2012;Topal et al, 2014). Previous studies have associated abnormalities in these parameters with exposure to pesticides, metals, and other toxicants (Suvetha et al, 2010;Atli and Canli, 2013;Kaur and Kaur, 2015).…”