Environmentally induced nephrotoxicity and histopathological alternations in Wallago attu and Cirrhinus mrigla

Evaluation of Hepatotoxic Potential of an Azo Dye, Eriochrome Black T on Freshwater Catfish, Clarias batrachus

Nowadays, textile industries are one of the major contributors to water pollution, causing a devastating impact on aquatic ecosystems. Therefore, the current study aimed to investigate the impact of a textile azo dye, Eriochrome Black T (EBT), on the liver of a freshwater fish, Clarias batrachus. Fish were exposed to three concentrations of EBT, i.e., 1 mgL-1, 10 mgL-1 and 20 mgL-1, to evaluate oxidative stress markers such as level of lipid peroxidation (LPO) and activity of enzymatic antioxidants (SOD, CAT, GPx and GR), as well as histology and histochemitry following 96 h of exposure. The results revealed a significant increase (p < 0.05) in EBT bioaccumulation, resulting in elevated level of LPO and significant variation (p < 0.05) in the activities of antioxidant enzymes. The percent change calculation of oxidative stress markers of exposed fishes from control one showed that EBT had most significant impact on the fishes exposed to 20 mgL-1 of EBT. Histological and histochemical examinations also demonstrated the deteriorating impact of EBT on structural architecture of liver. Hence, the present study concludes that EBT causes detrimental impact on fish health by impairing its liver detoxification system and metabolism. Therefore, it is suggested to explore mechanism of EBT toxicity on aquatic organisms so that its hazardous risk can be monitored and preventive measures can be taken.

Degradation of organic Pollutant by Using of BiVO4-NiFe2O4 Heterostructure Photocatalyst under Visible Light Irradiation: Assessment of Detoxicity Study Using Cirrhinus mrigala

The current study mainly concentrates on the photocatalytic activity of composite nanomaterial of BiVO4 (BVO), NiFe2O4 (NFO), and BiVO4-NiFe2O4 (BVO-NFO) under visible light. Among these, BVO-NFO composite degrades crystal violet dye within 60 min with a percentage degradation of 95.65% under visible light illumination. The BVO-NFO composite exhibits better photodegradation performance, which can be attributed to the effective light absorption and reduced recombination of the photoexcited charge carriers. Additionally, by applying a magnetic field, the BVO-NFO composite can be magnetically recovered by using the magnet for subsequent recycling. The synthesized composite was characterized using optical techniques like X-ray diffraction, ultraviolet diffuse reflectance spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller, and energy dispersive X-ray analysis. The effect of dye, before and after degradation, on vital organs of fish species was examined such as fish gill (pulmonary-toxicity), fish liver (hepato-toxicity), fish kidney (renal toxicity), fish brain (neural toxicity), and fish muscle (myopathy). This work offers a clear and practical method for designing a highly crystalline semiconductor photocatalyst for dye degradation and the remediation of industrial wastewater.

A Reversible Mechanochromic AIEgen Based on Triphenylamine for the Selective Detection of Vitamin B2 (Riboflavin) in Aqueous Media and Histotoxicity

(E)-Ethyl 2-cyano-3-(4'-(diphenyl amino)-[1,1'-biphenyl]-4-yl) acrylate (RSJ) is a novel luminogen based on triphenylamine. It has been fully synthesized and characterized, exhibiting an incredible photophysical phenomenon known as aggregation-induced emission (AIE). This work describes a fluorescent sensor that detects vitamin B2 in mixed aqueous media with high selectivity and a low limit of detection as well as a mechanism for reversible mechanochromic luminescence. Moreover, the molecule was validated for its nontoxicity in water using a histotoxicological study. Fish subjected to two different concentrations of the "novel luminogen" that displayed photophysical phenomena during sensing of vitamin B2 (riboflavin) in mixed aqueous media did not exhibit any significant differences in the structural makeup of their liver, kidney, gills, brain, and muscle tissues when compared with the control group.

Histotoxicity of AIEgen Based on Triphenylamine for the Simultaneous and Discriminatory Sensing of Hg2+ and Ag+ Directly in Aqueous Media for Environmental Applications

A newly synthesized AIEgen based on triphenylamine is fully characterized and coded as BRA for the simultaneous and discriminatory selective detection of Hg2+ and Ag+ ions directly in mixed aqueous media for the identification and purification of water with a low detection limit. Moreover, we employed BRA in histotoxicity in that when compared to the control group, fish exposed to the "novel synthesized luminogen (BRA)" that demonstrated photophysical phenomena during the "sensing of mercury and silver (heavy metals) in aqueous media" did not show any major distinguishing changes in the architecture of their gills, liver, muscle, brain, kidney, and heart tissues.

Construction of Waste Chalk Powder into mpg-C3N4-CaSO4 as an Efficient Photocatalyst for Dye Degradation under UV-Vis Light and Sunlight

In this article, we present the synthesis of calcium sulfate nanoparticles (CaSO₄ NPs) from waste chalk powder by the calcination method. These CaSO₄ NPs were utilized for the construction of a mesoporous graphitic carbon nitride-calcium sulfate (mpg-C₃N₄-CaSO₄) photocatalyst. Synthesized materials were confirmed by several characterization techniques. The photocatalytic performance of the synthesized samples was tested by the degradation of methylene blue (MB) in the presence of both UV-vis light and sunlight. The efficiency of photocatalytic degradation of MB dye using the optimized mpg-C₃N₄-CaSO₄-2 composite reached 91% within 90 min in the presence of UV-vis light with superb photostability and recyclability after five runs compared to individual mpg-C₃N₄ and CaSO₄ NPs and reached 95% within 120 min under sunlight. Histotoxicological studies on fish liver and ovary indicated that the dye containing the solution damaged the structure of the liver and ovary tissues, whereas the photodegraded solution of MB was found to be less toxic and caused negligible alterations in their typical structure similar to the control group.

Long term exposure to tris (2-chloroethyl) phosphate (TCEP) causes alterations in reproductive hormones, vitellogenin, antioxidant enzymes, and histology of gonads in zebrafish (Danio rerio): In vivo and computational analysis

In aquatic milieus, tris (2-chloroethyl) phosphate (TCEP) was detected as an emerging environmental contaminant. In this study, in vivo experiment and in-silico docking was integrated systematically to explore the toxic mechanisms of TCEP using zebrafish (Danio rerio). Fish (mean weight of 0.24 ± 0.02 g) were exposed to 100 and 1500 μg L^-1 concentrations of TCEP for 28 days under the static renewal method. During chronic exposure, plasma steroid hormones such as testosterone (T) and 17β estradiol (E2), plasma vitellogenin (Vtg) and antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and lipid peroxidation (LPO) in gonads were significantly (P < 0.05) altered in TCEP exposed group (1500 μg L^-1) compared to the control group. However, the alterations of these parameters were not significant on the 14th day (except Vtg and GR in testis) in 100 μg L^-1 of TCEP exposed groups. There were no significant differences (p > 0.05) in the growth parameters comparing TCEP exposed groups with the control group. The gonads of fish exposed to TCEP showed significant histopathological changes when compared to the control groups. A docking study observed that TCEP possessed binding affinity with the estrogen receptor (ERβ) and androgen receptor (AR). These data indicate that TCEP at tested concentrations adversely affects the aquatic organisms.

In vivo assessment of dichlorvos induced histological and biochemical impairments coupled with expression of p53 responsive apoptotic genes in the liver and kidney of fish, Channa punctatus (Bloch, 1793)

Sub-lethal exposure of dichlorvos induces oxidative stress, consequent genetic instability and apoptosis coupled with impairments in biochemical, histopathological and transcription of genes in Channa punctatus. Exposure of 5% (0.041 mg/L; E2) and 10% (0.082 mg/L; E3) of 96 h-LC₅₀ of dichlorvos significantly (p < 0.05) elevated the reactive oxygen species (ROS) generation and activities of SOD and CAT, as compared to control (E1) after 30 d. The maximum reduction in reduced glutathione (GSH) was recorded in the liver (18.53 ± 0.81 μg/mg of protein) and kidney (19.32 ± 0.97 μg/mg of protein); while the total protein contents were also found reduced, 278.38 ± 8.40 μg/mL (liver) and 248.44 ± 7.28 μg/mL (kidney), after 30 days in E3, in comparison to respective controls. Further, significant (p < 0.05) induction in micronuclei (MN) and apoptotic cells (AC), in a dose- and exposure-based manner were also recorded. Moreover, a significant (p < 0.05) up-regulation of p53 (2.51-fold in liver), bax (2.03-fold in liver; 1.99-fold in kidney) and casp3a (2.26-fold in liver; 2.10-fold in kidney) together with an elevated expression of cat (1.73-fold in liver; 1.12-fold in kidney), p53 (1.27-fold in kidney) and apaf-1 (1.72-fold in liver) in fish exposed to higher dose of dichlorvos for 30 d evidently reflects geno-toxicological potential of referenced pesticide. Disturbed biochemical and molecular parameters evince that the fish experienced oxidative stress as is further supported by prominent pathological observations in liver and kidney. Findings are, thus, helpful in organ-specific molecular scanning against aquatic toxicants like dichlorvos.

A study on risk assessment of effect of hematoxylin dye on cytotoxicity and nephrotoxicity in freshwater fish: Food and water security prospective research

The cytotoxicity in freshwater fishes due to different industrial dyes in industrial effluents is a major worldwide issue. Hematoxylin dye has a wide range of uses in textile industries and laboratories. This study was aimed to evaluate the toxic effects of hematoxylin's sublethal effect in vitro in Cirrhinus mrigala. The fish was exposed to different grading concentrations of dye in the aquarium. Fish were sacrificed and dissected to remove the kidney after exposure to hematoxylin dye for specific time intervals. Nephrotoxicity and cytotoxicity induced by this dye were detected through histopathology by using the paraffin wax method. Immediate mortality of fish was noticed against the exposure to 0.08 g/L (LC50) concentration of dye, but at 0.008 mg/L and 0.018 mg/L, it showed tremendous tissue damage in the kidneys, significant reduction in fish growth. This dye induced many alterations in the kidney such as tubular degeneration, vacuolation, shrinkage of a glomerulus, reduced lumen, congestion in the kidney, glomerulonephritis, absence of Bowmen space, necrosis of the hematopoietic interstitial tissues, clogging of tubules, necrosis in the glomerulus and increased space between glomerulus and bowmen's capsule. Although this dye has a wide range of biological and industrial applications, a minute amount of hematoxylin released in effluents is quite toxic to aquatic fauna.

Nephroprotective effect of Emblica officinalis fruit extract against malachite green toxicity in piscine model: Ultrastructure and oxidative stress study

Malachite green (MG) is a multi-application dye with raised concern as aquatic toxicant. Cyprinus carpio fingerlings were exposed to MG and simultaneously fed with Emblica officinalis (EO) fruit extract to mitigate the MG induced nephrotoxicity. MG exposure developed depressed activity of antioxidant enzymes such as catalase, superoxide dismutase, glutathione-s-transferase, and reduced glutathione, while levels of malondialdehyde got significantly (p < .05) elevated after 60 days MG exposure. H&E staining revealed increased intracellular space, vacuolation, fluid-filled spaces, damaged brush border lining of proximal convoluted tubule (PCT), focal necrosis, nuclear transformations and shrunken glomerulus. Further, Transmission electron microscope study detailed structural cytotoxicity with the appearance of the heterochromatic nucleus, electron-dense lysosomal bodies, damaged brush border lining of PCT, and necrosis; glomerulus exhibited erythrocyte infiltration and fused pedicels of podocyte. While, EO extract supplemented diet culminated in the restoration of the renal cytoarchitecture and significantly (p < .05) enhanced activity of antioxidant enzymes.