Abstract
The current study aimed to monitor the impact of H(2)O(2)-induced oxidative stress on avian bone formation during the early stage of embryonic development. Fertilized Cobb broiler eggs were divided into five treatment groups and micro-injected with varying concentrations of H(2)O(2), i.e., control (PBS; 0 nM), 10 nM, 30 nM, 100 nM, and 300 nM, on embryonic day 3, with continued incubation thereafter. The treatment concentrations were selected based on the level of lipid peroxidation and the survival rate of embryo. Embryos were collected at 6 h, 24 h, 48 h, and 72 h post-injection. The mRNA expression levels of apoptotic markers, antioxidant enzymes, and early bone formation gene markers were measured. The results showed that the microinjection of H(2)O(2) altered the expression pattern of antioxidant enzymes' mRNA during early embryogenesis and decreased the expression of COL1A2 and COL2A1 at 6 h and 24 h post-injection. Decreased expression of BMP, BGLAP, and RUNX2 was observed 48 h post-injection. Additionally, a shorter embryo length was observed in the 100 nM and 300 nM H(2)O(2) treatment groups 72 h post-injection. In conclusion, H(2)O(2)-induced oxidative stress suppressed the expression of bone formation gene markers, with chronic effects on avian embryonic development.