Evaluation of Fish Health Status and Histopathology in Gills and Liver Due to Metal Contaminated Sediments Exposure

Heat shock proteins (HSP) are highly conserved in their structure and released in case of stress. Increased metallothionein (MT) synthesis is associated with increased capacity for binding heavy metals. Healthy juveniles of grass carp were exposed to sublethal dose (1.495 mg L-1) of cadmium for 28 days. Simultaneously, a control group was also run to compare difference of total RNA expression levels in cadmium-treated and control groups. The cadmium levels in the tissues of treated fish recorded were 1.78 ± 0.10 mg L − 1 , 1.60 ± 0.04 mg L − 1 , and 2.00 ± 0.05 mg L − 1 , respectively. Several histological alterations including edema, hemorrhage, dilated sinusoids, hypertrophy, hyperplasia, congestion of central vein, and nuclear alterations were observed in cadmium-exposed fish. Stress gene (metallothionein and heat shock proteins) mRNA transcription levels were studied by mRNA extraction and cDNA preparation by using PCR. The expression level of heat shock protein gene was higher as compared to metallothionein and beta-2-microglobulin gene after cadmium exposure. This study reports various stress-related immune-responsive changes of immune proteins, heat shock proteins, metallothionein, and histopathological changes in fish due to cadmium toxicity that make the fish immunocompromised which may be considered as the biomarkers of cadmium toxicity in other experimental species.

BioMed Research International

Section: Methodsmentioning

confidence: 99%

Investigation on Immune-Related Protein (Heat Shock Proteins and Metallothionein) Gene Expression Changes and Liver Histopathology in Cadmium-Stressed Fish

Jabeen

Ishaq

Fatima

et al. 2022

Self Cite

“…Histopathological examination of two major organs responsible for accumulation and elimination of toxicants in fishes, liver and kidney was performed to further evaluate the toxic potential of HgCl 2 . Sufficient data are present regarding metal‐induced histopathological changes in Piscean species (Álvarez‐Muñoz et al ., 2009; Hampel et al ., 2008; Jabeen et al ., 2019; Padrilah et al ., 2018). Similarly, Awasthi et al .…”

Section: Discussionmentioning

confidence: 99%

Mercuric chloride‐induced oxidative stress, genotoxicity, haematological changes and histopathological alterations in fish Channa punctatus (Bloch, 1793)

Singh

Journal of Fish Biology

et al. 2022

The present study was undertaken to investigate the adverse effects of mercuric chloride (HgCl2) overload in the fish Channa punctatus. Two sublethal test concentrations of HgCl2 (1/20th and 1/10th of 96 h LC50 i.e., 0.03 mg l−1 (low concentration) and 0.07 mg l−1 (high concentration), respectively, were used for exposure. Blood, liver and kidney tissues of the control and exposed specimens were sampled at intervals of 15, 30, and 45 days to assess alterations in oxidative stress, genotoxicity haematological parameters and histopathology. Significant changes in Hb%, RBC count, WBC count, antioxidant enzyme activity, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione reductase (GR), were recorded. Micronuclei (MN) induction, nuclear abnormalities (NAs) and histopathological alterations were also observed in the exposed fish. Significant (P < 0.05) increase in the activities of SOD, CAT, GSH and GR was observed. After 45 days, a decrease in the level of GSH and GR was noticed which suggests an undermined anti‐oxidative defence system in the fish exposed to HgCl2. Histological examination of the liver and kidney showed serious tissue injury and histological alterations. Significant increases in MN and NA frequencies reveal the DNA damage in erythrocytes of fish, and haematological changes show the toxicological potential of HgCl2. The observed changes in the antioxidant defence system, genotoxicity and haematological and histological changes in the present study provide the most extensive insight into HgCl2 stress in C. punctatus.

“…Histopathological examination of two major organs responsible for accumulation and elimination of toxicants in shes, liver and kidney was done to further evaluate the toxic potential of HgCl 2 . Ample number of data is present regarding metal induced histopathological changes in Piscean species (Álvarez-Muñoz et al, 2009;Hampel et al, 2008;Jabeen et al, 2019;Padrilah et al, 2018). Similarly, Awasthi et al, (2019) have also documented the histopathological alterations as the end-point marker for assessment of toxic potential of heavy metal in liver tissues of sh, Channa punctatus.…”

Section: Discussionmentioning

confidence: 99%

Mercuric Chloride induced Oxidative Stress, Genotoxicity, Haematological Changes and Histopathological Alterations in Fish Channa Punctatus (Bloch, 1793).

Singh

et al. 2021

Preprint

The current study was strived to investigate the adverse effects of Mercuric chloride (HgCl2) overload in the fish Channa punctatus. Two sub-lethal test concentrations of HgCl2 viz., 1/20th and 1/10th of 96 h LC50 i.e., 0.03 mg/L and 0.07 mg/L, respectively, were used for exposure. Blood, liver and kidney tissues of the control and exposed specimens were sampled at intervals of 15, 30 and 45 days to assess alterations in oxidative stress, genotoxicity haematological parameters and histopathology. Significant changes in Hb%, RBC count, WBC count, antioxidant enzyme activity viz., super oxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione reductase (GR) were recorded. Micronuclei (MN) induction, nuclear abnormalities (NA) and histopathological alterations were also observed in the exposed fish. Significant (p < 0.05) increase in activities of SOD, CAT, GSH, GR and after 45 d decrease in the level of GSH and GR suggest an undermined anti-oxidative defence system in the fish exposed to HgCl2. Histological examination of liver and kidney showed serious tissue injury and histological alterations. Significant increase in MN and NA frequencies reveal the DNA damage in erythrocytes of fish and haematological changes show the toxicological potential of HgCl2. The observed genotoxicity, biochemical, haematological and histological changes in the present study provide the most extensive insight of HgCl2 stress in Channa punctatus.