Evaluation of the Effect of Zinc on Fipronil Induced Hepatic Toxicity in Adult Male Albino Rats

Abstract

Background: Fipronil showed toxicity in mammals and in insects, it was documented to have adverse effects to organs such as liver. Zinc homeostasis is primarily regulated in the liver, so the chronic liver damage results in impairment of zinc homeostasis and eventually zinc deficiency.

Aim: to study protective effect of zinc on liver toxicity induced by fipronil in adult male albino rats through biochemical, histopathological and genotoxic studies.

Main methods: In the present study, forty adult healthy male albino rats weighing 180 - 200 gm, were used. They were divided into 4 groups as following:Group I(control group): It was subdivided into 2 groups each of 8 rats; Group IA (negative control group) 8 rats:

Rats received no medication, only regular diet and water to measure the basic parameters for 6 weeks, Group IB (positive control group) 8 rats: Each rat treated with 1 ml distilled water (the vehicle of fipronil and zinc) by oral gavage once daily for 6 weeks. Group II (zinc group) 8 rats:

Each rat was gavaged orally with 2mg/kg bw zinc as powder dissolved in 1 ml distilled water once daily for 6 weeks.Group III (fipronil group) 8 rats: Each rat was gavaged orally with 9.7 mg/kg bw fipronil dissolved in 1 ml distilled water once daily for 6 weeks which equals 1/10 of LD50.Group IV (zinc+fipronil) 8 rats:    Each rat was gavaged orally with 2mg/kg bw zinc as powder dissolved in 1 ml distilled water. An hour later; Fipronil was gavaged orally with 9.7mg/kg bw fipronil dissolved in 1 ml distilled water once daily for 6 weeks. At the end of 6 weeks, all rats were anesthetized then subjected to blood samples collection for estimation of serum biomarkers of liver function tests (ALT, AST, ALP & LDH), oxidative stress (MDA) and Antioxidant biomarkers SOD &GPX).

Results: The results of the present study revealed  that zinc administration with FPN  resulted in a significant decrease in the mean values of serum ALT, AST & ALP & LDH of Zinc with fipronil group when compared with FPN treated group, zinc administration with FPN resulted in a very highly significant decrease in the mean values of serum (MDA , GPX &SOD)  of Zinc with fipronil group when compared with FPN treated group, The results revealed some improvement in histopathological changes in zinc+FPN treated group indicated by normal central vein, minimal dark pyknotic nuclei with mild vacuolation and minimal blood sinusoidal congestion, minimal cellular infiltration.

Conclusion: Our findings prove that Zinc plays an important role in protection against fipronil liver toxicity evidenced by improving the biochemical, histopathological and comet assay results in groups treated with zinc and fipronil.