Antioxidant defence in the brain of 1-d-old chickens exposed in ovo to acrylamide

ABSTRACT

1. Acrylamide (ACR) is a potent neurotoxicant, although information on its toxic influence on the developing neural system is still limited. The effects of in-ovo-injected ACR on the antioxidant system activity in the brain of newly hatched chickens was examined. This model eliminated the mother’s contribution to embryonic development. It was also recognised as an adequate model for animal embryonic development.

2. ACR was injected on d 4 of embryogenesis – in doses of 1.25 and 2.50 mg/egg (n = 40 eggs/group/120 eggs). The doses corresponded well with ACR doses used in other animal studies and their concentrations in certain animal feeds.

3. Mortality and incidences of malformations were not found to increase significantly. Significant depletion of glutathione was detected in the cerebellum, cerebrum and medulla oblongata of specimens exposed to the highest doses of ACR. Enzymatic activity was affected by the highest ACR doses. Glutathione peroxidase (GPx) activity increased significantly in the cerebrum, medulla oblongata and the hypothalamus. Superoxide dismutase (SOD) activity increased significantly in hypothalamus and decreased in cerebellum and cerebrum. A significant depletion of catalase (CAT) activity was detected in cerebellum. In the hypothalamus, the increased SOD/GPx and SOD/CAT ratios suggest the risk of H₂O₂.

4. It was concluded that ACR significantly influences the antioxidative defence in the chicken brain at doses of 1.25 and 2.50 mg/egg.

KEYWORDS:

• Acrylamide
• antioxidative enzymes
• brain
• chicken
• embryos
• reduced glutathione

Acknowledgement

The authors cordially thank Dr Barbara Tombarkiewicz, Head of Institute of Veterinary Sciences, Agricultural University in Krakow, for the possibility to perform in ovo experiments in professional incubators.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the Department of Animal Physiology and Toxicology, Institute of Biology, Faculty of Geography and Biology, Pedagogical University of Cracow, Kraków, Poland.