destruction causes macrocytic anaemia with low haemoglobin content causing
dysfunction of organs [80]. Similar results were recorded in Oreochromis niloticus
exposed to drug sulfamethazine [74] and in Pangasianodon hypophthalmus exposed
to triclosan [81].
Alterations of plasma carbohydrates levels act as a non-specific hallmark of
disturbed physiology as they are considered as the foremost organic nutrients to be
degraded in response to in fishes during stress conditions [82]. A rise in the plasma
glucose concentration indicates high utilization of glucose to cope the metabolic
stress caused by the drugs [83]. Furthermore, the increase in any of the stress
hormones catecholamines or corticosteroids may also lead to elevated plasma
glucose levels in fishes [84]. Similar observations were reported by Renuka et al.
[43] in N-acetyl-p-aminophenol-treated rohu fingerlings, Ambili et al. [85] in
oxytetracycline-treated rohu fingerlings and Umamaheswari et al. [86] in
amoxicillin-treated rohu fish fingerlings.
Protein serves as the primary energy source to meet energy demand at some point
in increased physiological and metabolic activities of fish under stress conditions
[87]. The observed decline in plasma protein level in ASA-exposed fishes might be
resulted from the free amino acid production and its utilization in TCA cycle for
energy production. ASA molecules are weak organic acids having the high affinity
for lipids and plasma proteins, and therefore they bind to the circulating free protein
molecules causing hypoproteinaemic condition in ASA-treated fishes. Hepatocytes
in liver synthesize most of the proteins. The liver is one of the core target organs for
the detoxification of toxicants. ASA accumulation in liver causes impaired protein
synthesis [88]. This observation is in accordance with the results of Saglam and
Yonar [89] who reported a decline in plasma protein content in sulfamerazineexposed Oncorhynchus mykiss.
Any stress condition in fish causes perturbations in enzymatic activities, thus
resulting in decreased growth rate and metabolic rate in fishes. Glutamate oxaloacetate transaminase (GOT or AST) and glutamate pyruvate transaminase (GPT or
ALT) are two important liver enzymes found in plasma and in various body tissues.
Serum ALT and AST level and their ratio are universally accepted clinical biomarkers for analysing liver health [90, 91]. In the present study, there were significant changes in GPT and GOT activity in plasma of C. carpio exposed to the
chronic concentration of ASA for 21 days. The depleted levels of GPT and GOT in
plasma indicate the incapability of destructed hepatocytes to release aminotransferases into the circulatory system [92]. The sudden increase in GPT and GOT activity
in plasma might be resulted from the hepatic tissue damage caused by the drug
[93]. Similarly, Ramesh et al. [4] documented on the significant alterations in the
freshwater fish Cyprinus carpio exposed to chloroquine.
Xenobiotics induce oxidative stress in aquatic animals mainly in fishes through
free radical and reactive oxygen species (ROS) mechanisms [41]. The liver is the site
of detoxification in fishes [94]. The detoxifying mechanism occurs in a sequence
involving biotransformation enzymes such as GST and antioxidants such as CAT,
SOD, and GPx [95]. The superoxide dismutase (SOD) mediates the first transformation by dismutation of superoxide free radicals (O 2
À
) into hydrogen peroxide
208
S. Siddeswaran et al.
dysfunction of organs [80]. Similar results were recorded in Oreochromis niloticus
exposed to drug sulfamethazine [74] and in Pangasianodon hypophthalmus exposed
to triclosan [81].
Alterations of plasma carbohydrates levels act as a non-specific hallmark of
disturbed physiology as they are considered as the foremost organic nutrients to be
degraded in response to in fishes during stress conditions [82]. A rise in the plasma
glucose concentration indicates high utilization of glucose to cope the metabolic
stress caused by the drugs [83]. Furthermore, the increase in any of the stress
hormones catecholamines or corticosteroids may also lead to elevated plasma
glucose levels in fishes [84]. Similar observations were reported by Renuka et al.
[43] in N-acetyl-p-aminophenol-treated rohu fingerlings, Ambili et al. [85] in
oxytetracycline-treated rohu fingerlings and Umamaheswari et al. [86] in
amoxicillin-treated rohu fish fingerlings.
Protein serves as the primary energy source to meet energy demand at some point
in increased physiological and metabolic activities of fish under stress conditions
[87]. The observed decline in plasma protein level in ASA-exposed fishes might be
resulted from the free amino acid production and its utilization in TCA cycle for
energy production. ASA molecules are weak organic acids having the high affinity
for lipids and plasma proteins, and therefore they bind to the circulating free protein
molecules causing hypoproteinaemic condition in ASA-treated fishes. Hepatocytes
in liver synthesize most of the proteins. The liver is one of the core target organs for
the detoxification of toxicants. ASA accumulation in liver causes impaired protein
synthesis [88]. This observation is in accordance with the results of Saglam and
Yonar [89] who reported a decline in plasma protein content in sulfamerazineexposed Oncorhynchus mykiss.
Any stress condition in fish causes perturbations in enzymatic activities, thus
resulting in decreased growth rate and metabolic rate in fishes. Glutamate oxaloacetate transaminase (GOT or AST) and glutamate pyruvate transaminase (GPT or
ALT) are two important liver enzymes found in plasma and in various body tissues.
Serum ALT and AST level and their ratio are universally accepted clinical biomarkers for analysing liver health [90, 91]. In the present study, there were significant changes in GPT and GOT activity in plasma of C. carpio exposed to the
chronic concentration of ASA for 21 days. The depleted levels of GPT and GOT in
plasma indicate the incapability of destructed hepatocytes to release aminotransferases into the circulatory system [92]. The sudden increase in GPT and GOT activity
in plasma might be resulted from the hepatic tissue damage caused by the drug
[93]. Similarly, Ramesh et al. [4] documented on the significant alterations in the
freshwater fish Cyprinus carpio exposed to chloroquine.
Xenobiotics induce oxidative stress in aquatic animals mainly in fishes through
free radical and reactive oxygen species (ROS) mechanisms [41]. The liver is the site
of detoxification in fishes [94]. The detoxifying mechanism occurs in a sequence
involving biotransformation enzymes such as GST and antioxidants such as CAT,
SOD, and GPx [95]. The superoxide dismutase (SOD) mediates the first transformation by dismutation of superoxide free radicals (O 2
À
) into hydrogen peroxide
208
S. Siddeswaran et al.