Background: Pollutants from industrial and commercial usage of chemicals all over the world that usually lead to release of myriads of toxic pollutants such as lead call for concern. Aim and Objective: The effects of lead nitrate on the production of antioxidants such as Alanine aminotransferase (ALT) in Clarias gariepinus and how such effects can be ameliorated through administration of vitamins were investigated. Materials and Methods: C. gariepinus fingerlings (whose initial weight ranged from 3 to 11 g) were exposed to sublethal concentrations of Pb (00, 26 mg/L, 44 mg/L, 61 mg/L, and 79 mg/L) with replicate in each case. 26 mg/L of the vitamins was administered across all bud. Fresh concentrations of both toxicant and vitamins were administered every 72 h for a period of 12 weeks every time the water medium was changed. The various treatments group include Pb (Pb only), PbVA (Pb + vitamin A), PbVC ((Pb + vitamin C), and PbVE (Pb + vitamin E) with T1-T4 and replicates in each case. Three samples of the fish were randomly selected and sacrificed from each aquarium tank every 2 weeks of the exposure period. The gills, kidneys, and liver were excised from these specimens and homogenized in sodium phosphate buffer. These were then assayed for ALT production levels in each case. The data generated were subjected to one-way analysis of variance and considered significant at P ≤ 0.05. Results: In samples exposed to Pb only group, the ALT production levels indicated that the highest ALT produced in the liver, kidney, and gills was 87.20 ± 0.15 nM/mg, 65.76 ± 0.20 nM/mg, and 69.92 ± 0.05 nM/mg, respectively. Samples exposed to PbVA indicated that the highest ALT produced in the liver, kidney, and gills was 77.12 ± 0.20 nM/mg, 84.75 ± 0.10 nM/mg, and 70.43 ± 0.24 nM/mg, respectively. Conclusions and Recommendation: In samples exposed to PbVC, the highest ALT produced in the liver, kidney, and gills was 86.53 ± 0.05 nM/mg, 63.48 ± 0.15 nM/mg, and 66.53 ± 0.15 nM/mg, respectively. In samples exposed to PbVE, the highest ALT produced in the liver, kidney, and gills was 73.82 ± 0.15 nM/mg, 78.05 ± 0.15 nM/mg, and 73.31 ± 0.05 nM/mg, respectively. The samples of the fish exposed to sublethal concentrations of the toxicant in the various treatments displayed varying levels of production of the enzyme with higher production levels mostly at higher concentrations of the toxicant. In the Pb only and PbVC groups, the liver of the samples produced the highest ALT, while the kidneys did same in the PbVA and PbVE groups. The high levels of production of the enzyme, especially in higher concentrations suggest physiological imbalances due to the presence of the toxicant.

Pollution of aquatic ecosystems is constantly increasing with the increase in anthropogenic activities all over the world with negative effects on the constituent biota. The current study addressed the possibility of remedying the effects posed to the tissues of Clarias gariepinus fingerlings (3-11g initial weight) exposed to lead nitrate over a 12 week period. The treatment groups were Pb only and PbVE (Pb+vitamin E) with T1-T4 and replicate in each case. The sub-lethal treatments of lead nitrate concentrations are as follow: 00 (control), 26mg/L (T1), 44mg/L (T2), 61mg/L (T3) and 79mg/L (T4). 26mg/L concentration of the vitamin was applied to every treatment and replicate of the PbVE group. At the end of the exposure period, gills, liver, and kidneys were excised from the samples and preserved in 10% formalin for histopathological analyses. From the results; the livers of the samples of C. gariepinus exposed to sub-lethal concentration of Pb only group displayed aggregation and lumping together of the hepatocytes, massive necrosis and shattering of the hepatocytes, vacoulation with greater severity as the concentration increased. The samples of PbVE treatment group showed preserved hepatocytes, reduced aggregation and vacoulation of the cells, gradual recovery of the cell nucleus and cytoplasm, normal tissue architecture, and hepatocytes similar to control samples in T1-T3. In the kidneys of Pb only group, there were massive necrosis and vacoulation, shattering of cells, tissue edema, and massive lumping of cells together, especially in higher concentrations. The PbVE treatments displayed reduced necrosis and cells aggregating together coupled with reduced vacoulation, preserved cells, and cells with cytoplasm returning to normal. But these were not sustained in the highest concentration. In the gills of the Pb only group, there was rarefied gill filament with ruptured lamellae, shattered gill arch, and filaments ruptured primary and secondary lamellae with greater severity in higher concentrations. The PbVE group displayed how the gill arch and filaments with the primary and secondary lamellae were gradually restored to a certain extent similar to the control. In all the organs the alteration and amelioration of the architecture were concentration-dependent. Therefore, a proportionate concentration of the vitamin can facilitate faster tissue damage recovery in heavy metal exposure.