Fipronil induced oxidative stress in neural tissue of albino rat with subsequent apoptosis and tissue reactivity

Histopathological and Behavioral Impairments in Zebrafish (Danio rerio) Chronically Exposed to a Cocktail of Fipronil and Pyriproxyfen

BACKGROUND

Lately, the high incidence of pesticide usage has attracted everyone's interest due to the serious effects produced. Fipronil (FIP) is a phenylpyrazole compound that acts on the insect's GABA neurotransmitter by inhibiting its activity. Moreover, the literature reports highlight its implication in neurodevelopmental abnormalities and oxidative stress production in different organisms. Similarly, pyriproxyfen (PYR) is known to affect insect activity by mimicking the natural hormones involved in the maturation of the young insects. The aim of the present study was to investigate the impact of the mixture of these pesticides on the tissues and behavior of zebrafish.

METHODS

To assess the influence of this cocktail on zebrafish, three groups of animals were randomly selected and exposed to 0, 0.05, and 0.1 mg L-1 FIP and PYR mixture for five days. The fish were evaluated daily by the T-maze tests for locomotor activity and the light-dark test and recordings lasted four min. The data were quantified using the EthoVision software.

RESULTS

Our results indicated significant changes in locomotor activity parameters that showed increased levels following exposure to the mixture of FIP and PYR. On the other hand, the mixture also triggered anxiety in the zebrafish, which spent more time in the light area than in the dark area. In addition, mixture-induced histological changes were observed in the form of numerous hemosiderin deposits found in various zebrafish tissues.

CONCLUSIONS

The current findings indicate that the mixture of FIP and PYR can have considerable consequences on adult zebrafish and may promote or cause functional neurological changes in addition to histological ones.

Betanin ameliorates fipronil-induced nephrotoxicity via activation of Nrf2-HO-1/NQO-1 pathway in albino rat model

Fipronil (FPN) is phenylpyrazole insecticide extensively used to control a wide variety of pests. Betanin (BET) is a natural colorant with promising antioxidant and anti-inflammatory effects. This study aimed to investigate the potential protective effect of BET on FPN induced nephrotoxicity in adult male albino rats. Forty rats were assigned into 4 equal groups; Group I (Control); Group II (BET) received 20 mg/kg b.wt/day; Group III (FPN) received 4.8 mg/kg b.wt/day; and Group IV (BET/FPN). All treatments were given orally for 90 days. At the end of experiment, blood samples were collected for analysis of serum urea and creatinine. Kidneys were harvested for determination of kidney injury molecule-1(KIM-1) level; gene expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H: quinone oxidoreductase-1 (NQO-1); oxidative stress biomarkers including malondialdehyde (MDA), protein carbonyl content (PCC), catalase activity (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH). Histopathological examination and immunohistochemical investigation of Nrf2, nuclear factor kappa B (NF-κB), and caspase-3 were also undertaken. The results revealed kidney dysfunction, downregulation of Nrf2, HO-1, and NQO-1 genes, redox imbalance, structural damage, decreased Nrf2 and increased NF-κB immune-expression, in addition to strong caspase-3 immunoreactivity in FPN-treated group. In the combined group, BET co-administration resulted in functional and structural amelioration, up-regulation of Nrf2, HO-1, and NQO-1 genes, mitigation of redox imbalance, and strong anti-inflammatory and antiapoptotic effects. In conclusion, BET via activation of Nrf2-HO-1/NQO-1 pathway, exhibits beneficial antioxidant, anti-inflammatory, and antiapoptotic effects against FPN-induced nephrotoxicity.