Investigating the effects of copper sulfate and copper oxide nanoparticles in Nile tilapia (Oreochromis niloticus) using multiple biomarkers: the prophylactic role of Spirulina

Deleterious effects of polypropylene released from paper cups on blood profile and liver tissue of Clarias gariepinus: bioremediation using Spirulina

Despite numerous studies on microplastics, the biological impacts of polypropylene microplastics (PP-MPs) and its toxicity on freshwater fish have yet to be fully revealed. The purpose of this research was to look at the potentially harmful effects of PP-MPs in freshwater African catfish Clarias gariepinus and bioremediation using Spirulina. After acclimatization to laboratory conditions, 108 fish (125 ± 3 gm and 27 ± 2 cm) were assigned into triplicate six experimental groups (12 fish/group), a control group, Spirulina group (SP), PP-MP-treated groups (0.14 and 0.28 mg/l PP-MPs), and PP-MP + Spirulina-treated groups (0.14 mg/l PP-MPs + 200 mg/L SP and 0.28 mg/l PP-MPs +200 mg/L SP) for 15-day exposure and 45-day recovery after that. The hematological parameters exhibiting significance (RBCs, Hct, Hb, and MCV) or non-significance (MCH and MCHC) either decreased with the increase in PP-MP doses from 0.0 in the control to 0.28 mg/L red blood cells (RBCs), hematocrit (Hct), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb) and platelets or increased with such an increase in doses (mean corpuscular volume (MCV)). The liver enzyme activity, aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) exhibited non-significant (p ≥ 0.05) or significant (p < 0.05) increases in (0.14 and 0.28 mg/L) PP-MP-exposed groups, respectively, except ALP. Furthermore, there was a significant (p < 0.05) or non-significant (p ≥ 0.05) increase in 0.14 and 0.28 mg/l PP-MP +200 mg/L-exposure groups, respectively, compared to the control group and the same exposure group without Spirulina. In comparison to the control group, PP-MPs (0.14 and 0.28 mg/L) induced a significant (p < 0.05) increase in the percentage of poikilocytosis and nuclear abnormalities of RBCs. The liver tissue from fish exposed to PP-MPs exhibited varying degrees of pathological changes. These results indicated that these pathological changes increased with PP-MP concentration, suggesting that the effect of PP-MPs was dose-dependent. After 45 days of recovery under normal conditions, it was obvious that there was a significant improvement in the percentage of poikilocytosis and nuclear abnormalities of RBCs, as well as a non-significant improvement in hemato-biochemical parameters and liver tissue.

A biofloc system avoids the adverse effects of diets with suboptimal protein levels on zootechnical performance, intestinal histomorphometry, and protein metabolism of Nile tilapia juvenile fed Spirulina biomass (Arthrospira platensis) as an alternative protein source

This study aimed to evaluate the effect of the biofloc technology (BFT) system and the replacement of fish meal with Spirulina biomass on productive performance, intestinal histomorphometry, plasma biochemistry, and oxidative stress of Nile tilapia juveniles (Oreochromis niloticus) fed suboptimal levels of protein. Two factors were evaluated: production systems (clear water × BFT) and replacement of fish meal with Spirulina (0, 33, 66 e 100%). The design was in a 2 × 4 randomized factorial scheme with four replications, and the fish were evaluated for 48 days. Four isoproteic (28% crude protein) diets were formulated with gross energy values close to 4300 kcal kg-1. Nile tilapia juveniles (0.23 ± 0.01 g) were distributed in 16 circular tanks (70 L) at seven fish/tank. The diets were formulated with protein levels approximately 20% below that required for the species and life stage. No interaction was observed between the factors evaluated (production systems × Spirulina inclusion). Rearing the fish in the BFT system avoided the adverse effects of diets with suboptimal protein levels on performance, intestinal histomorphometry, and protein metabolism. Lower values lower lipid peroxidation and higher antioxidant capacity were observed in fish reared in the BFT system, showing evidence of improvements in antioxidant responses and lower levels of physiological oxidative stress. Spirulina completely replaced fish meal in the diets of Nile tilapia juveniles without adverse effects on intestinal morphometry, protein metabolism, and antioxidant response. Replacing 66% of fish meal with Spirulina improved the productive performance, regardless of the rearing system.

Effects of dietary garlic (Allium sativum) oil on growth performance, haemato-biochemical and histopathology of cypermethrin-intoxicated Nile tilapia (Oreochromis niloticus)

BACKGROUND

When pesticides are introduced into wetlands by agriculture, fish quickly absorb them through their gills. Pesticides reduce hatchability, impede growth, and antioxidant response, killing fish. Therefore, it's crucial to find effective pesticide mitigation methods for fish.

OBJECTIVE

In this study, the effects of garlic (Allium sativum) oil on the growth, haematology, biochemistry and histopathology parameters of Nile tilapia (Oreochromis niloticus) exposed to cypermethrin toxicity were investigated.

METHODS

In the research, cypermethrin was added to the water of the experimental groups at a rate of 1:20 of the LC50 value, and 1.00% garlic oil was added to the fish feed. Fish with an initial weight of 30.26 ± 0.26 g were fed for 45 days.

RESULTS

At the end of feeding, the final weights were determined as 69.39 ± 0.41 (G1), 61.81 ± 0.65 (G2), 82.25 ± 0.36 (G3), and 75.04 ± 0.68 (G4) grams, respectively. Histopathological examinations revealed serious lesions in the gill, liver, brain, and muscle tissues in the cypermethrin group, whereas these lesions were minimal or absent in the garlic oil group.

CONCLUSIONS

Garlic oil supplementation had positive effects on growth, haematology, blood biochemistry, hepatosomatic index and histopathological parameters. These findings suggest that garlic oil is a potential protective agent against cypermethrin toxicity.

Is the trend toward a sustainable green synthesis of copper oxide nanoparticles completely safe for Oreochromis niloticus when compared to chemical ones?: using oxidative stress, bioaccumulation, and histological biomarkers

Scientists worldwide have noticed that cutting-edge technologies can be used to produce nanoparticles (NPs) in a sustainable and environmentally friendly way, instead of the old methods. However, the effectiveness of this approach for aquatic environments and species still needs to be determined. Therefore, this study aims to compare between the toxicity of green and chemically synthesized copper oxide nanoparticles (GS and CS) CuO NPs at two different concentrations on Nile tilapia (Oreochromis niloticus) using various biomarkers. CuO NPs' formation was proved, and their different characterizations were recorded. Then, the fish samples were randomly allocated in glass aquaria into five groups: one acted as a control group, and the other groups were exposed to two concentrations (25 and 50 mg/L) of GS-CuO NPs and CS-CuO NPs, separately, for 4 days. After the experimental time, in all groups that were exposed to two concentrations of both synthesized CuO NPs, the results revealed that glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactive substances (TBARS) levels were elevated in the liver and gills compared to glutathione reduced (GSH) content, which showed a significant decline. Bioaccumulation of Cu was more prevalent in the liver than in the gills, and the highest bioaccumulation capacity was more evident in the groups exposed to CS-CuO NPs. Moreover, the bioaccumulation of Cu caused severe histological changes in the liver and gills. In conclusion, the results suggested that GS-CuO NPs revealed less toxicity than CS-CuO NPs to the examined fish. However, they are still toxic, and their toxic effect cannot be overlooked.

Oxidative stress, antioxidant defense responses, and histopathology: Biomarkers for monitoring exposure to pyrogallol in Clarias gariepinus

Pyrogallol promotes free radicals leading to oxidative stress and toxicity. There are however a lack of studies on oxidative stress and the antioxidant system of fish following exposure to pyrogallol. This study measured oxidative stress markers, antioxidant responses, and histological changes in catfish exposed to pyrogallol. Fish were divided into one of four experimental groups: control only, or 1, 5 or 10 mg/L pyrogallol. After 15 days, glutathione-S-transferase in the serum was decreased in fish exposed to either 5 or 10 mg/L pyrogallol relative to controls while superoxide dismutase and total antioxidant capacity were decreased significantly in fish exposed to 1, 5, or 10 mg/L pyrogallol. Conversely, catalase was increased in serum of fish exposed to 1, 5, or 10 mg/L pyrogallol compared to controls. The liver of fish treated with 1, 5, or 10 mg/L pyrogallol had significantly higher levels of oxidative stress markers (malondialdehyde, lipid peroxidation, hydroperoxide content, oxidised protein content, and DNA fragmentation %) that varied with concentration. Catfish exposed to either 1, 5, or 10 mg/L pyrogallol presented with notable histological alterations in the intestine, kidney, and muscles with prominent fibrosis, as intense deposition of collagen fibre was observed by Masson's trichrome staining. Overall, endpoints related to oxidative stress and antioxidant defence enzymes in fish may be early biomarkers of pyrogallol exposure and contamination in aquatic ecosystems. Additional studies should characterize oxidative stress indicators for their utility as biomarkers of effect.

Exposure to pyrogallol impacts the hemato-biochemical endpoints in catfish (Clarias gariepinus)

Pyrogallol is widely used in several industrial applications and can subsequently contaminate aquatic ecosystems. Here, we report for the first time the presence of pyrogallol in wastewater in Egypt. Currently, there is a complete lack of toxicity and carcinogenicity data for pyrogallol exposure in fish. To address this gap, both acute and sub-acute toxicity experiments were conducted to determine the toxicity of pyrogallol in catfish (Clarias gariepinus). Behavioral and morphological endpoints were evaluated, in addition to blood hematological endpoints, biochemical indices, electrolyte balance, and the erythron profile (poikilocytosis and nuclear abnormalities). In the acute toxicity assay, it was determined that the 96 h median-lethal concentration (96 h-LC50) of pyrogallol for catfish was 40 mg/L. In sub-acute toxicity experiment, fish divided into four groups; Group 1 was the control group. Group 2 was exposed to 1 mg/L of pyrogallol, Group 3 was exposed to 5 mg/L of pyrogallol, and Group 4 was exposed to 10 mg/L of pyrogallol. Fish showed morphological changes such as erosion of the dorsal and caudal fins, skin ulcers, and discoloration following exposure to pyrogallol for 96 h. Exposure to 1, 5, or 10 mg/L pyrogallol caused a significant decrease in hematological indices, including red blood cells (RBCs), hemoglobin, hematocrit, white blood cells (WBC), thrombocytes, and large and small lymphocytes in a dose-dependent manner. Several biochemical parameters (creatinine, uric acid, liver enzymes, lactate dehydrogenase, and glucose) were altered in a concentration dependent manner with short term exposures to pyrogallol. Pyrogallol exposure also caused a significant concentration-dependent rise in the percentage of poikilocytosis and nuclear abnormalities of RBCs in catfish. In conclusion, our data suggest that pyrogallol should be considered further in environmental risk assessments of aquatic species.

The synergetic effects of 4-nonylphenol and polyethylene microplastics in Cyprinus carpio juveniles using blood biomarkers

Microplastics are widely distributed in aquatic ecosystems along with other chemical pollutants. Therefore, it is vital to study the health-hazardous effects of MPs in combination with 4-nonylphenol (4-NP), which is a highly abundant industrial waste and a critical alkylphenol endocrine disruptor. We investigated the effects of the exposure to polyethylene microplastics (PE-MPs), 4-NP, and their combination on blood biomarkers in Cyprinus carpio juveniles. Four study groups were treated for 15 consecutive days: (1) control group, (2) 10 mg/L PE-MP group, (3) 10 mg/L PE-MPs + 200 µg/L 4-NP group, and (4) 200 µg/L 4-NP group, followed by 15 days of recovery. Biochemical analyses showed that creatine kinase, lactate dehydrogenase, glucose, liver enzymes, total protein, and A/G ratios were significantly increased after exposure to PE-MPs, 4-NP, and the combination. Hematological parameters (RBC's, Hb, Ht, neutrophil percentage, and WBC's) were significantly decreased in the three exposure groups, whereas mean corpuscular volume and lymphocyte percentages were significantly increased. The 15-day recovery period improved most hematobiochemical parameters and PE-MP accumulation indices. Taken together, we demonstrated the hazardous effects of PE-MP and 4-NP combinations on C. carpio blood parameters and highlighted their potential risk to human health.

Copper sulfate induces clinico-hematological, oxidative stress, serum biochemical and histopathological changes in freshwater fish rohu (Labeo rohita)

Despite being an essential trace element for numerous metabolic processes and micronutrients, copper (Cu) has induced adverse effects on the environment and public health due to its continuous and widespread use for the last several decades. The current study assessed the hematological and histopathological alterations in the freshwater fish (Labeo rohita) exposed to graded concentrations of copper sulfate. For this purpose, L. rohita fish (n = 72), weighing ~200-215 g, were randomly divided into four experimental groups and then exposed to acute doses of CuSO4, i.e., control, 0.28, 0.42, and 0.56 μgL-1. For comparative analysis of hematological and biochemical changes, blood/serum samples were obtained on 12, 24, and 36 days. Overall, the body weight of fish decreased with the time and dose of CuSO4; as the dose increases, body weight decreases. Dose and time-dependent results were observed in other parameters also. Results showed a significant increase in leukocytes, whereas red blood cells count, Hb, and Hct were significantly reduced in treated groups compared to the control. The mean corpuscular hemoglobin (MHC) and mean corpuscular hemoglobin concentration (MCHC) showed a non-significant decrease in treated groups compared to the control group. Serum biochemical parameters, including total proteins, albumin, and globulin, decreased significantly (p < 0.05). At the same time, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glucose, and cholesterol were significantly (p < 0.05) increased in the treated groups compared to the control group. Significantly (p < 0.05) increased levels of lipid peroxidation while decreased values of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (RGSH) in the blood of fish were recorded. Histopathological examination of fish gills, liver, and kidneys showed inflammation and degenerative changes due to CuSO4 exposure. In the brain tissue, degenerative changes like neuron necrosis, intracellular edema, cytoplasmic vacuolization, and congestion were observed. In conclusion, the study indicates that exposure to copper sulfate, even in smaller concentrations, can cause adverse hematological and histopathological changes in L. rohita fish.