Immunohistochemical Effects of Lutein on Paraquat-induced Toxicity in Kidneys and Liver of Adult Wistar Rats

Abstract

Introduction: Paraquat is one of the major causes of herbicide-related death globally, and lacks effective treatment till date. Lutein has a free radical scavenging ability with potential for amelioration and preservation of hepatorenal pattern following chemical poisoning. Objective: The study evaluated the immunohistochemical effects of lutein on paraquat-induced toxicity in kidney and liver of adult Wistar rats. Methods: Thirty-five male Wistar rats weighing between 150 and 180 g were randomly assigned to five experimental groups (A–E). Paraquat-induced toxicity was established in Groups B through E by administering 5 mg/kg for three consecutive days, while Group A served as the control and received normal saline only. Following induction, Groups C, D, and E were treated with lutein at doses of 50, 100, and 150 mg/kg, respectively, for a period of 21 days. Body weights were monitored and recorded twice weekly throughout the study. At the end of the experimental period, the animals were euthanized, and the liver and kidneys were harvested, excised, and processed for analysis. Immunohistochemical staining was performed using 4-hydroxynonenal as a biomarker of lipid peroxidation, followed by standard incubation procedures and slide preparation. The prepared slides were digitized using a Motic Easy Scanner. Results: Immunohistochemical assessment of lipid peroxidation in the kidneys and liver of control group A showed decreased expression of 4-HNE. However, there was an increased expression of the antibody in the PQ-only group; other groups (C-E) that had graded dosages of lutein demonstrated decreased expression of 4-HNE in a dose dependent manner. Conclusion: The findings of this study showed that lutein demonstrated dose-dependent attenuation of lipid peroxidation in the treated groups, indicative of progressive improvements in the immunohistochemical features, which were closely similar to the control when the highest dose of lutein was given. Accordingly, lutein may be regarded as a promising therapeutic candidate for mitigating the toxic effects associated with paraquat exposure.