Effects of Chronic and Acute Heat Stress on the Cardiac Expression of Antioxidative and Anti-Inflammatory Genes in Chicks

Bastaki, N. KAlmomen, J. ZAlbarjas, T. A

Heat stress can affect several biological pathways. This study aimed to compare the effects of chronic and acute heat stress on the oxidative status and inflammatory responses of chick's hearts. Chronic and acute heat stress were induced in chicks, heart tissues were examined for morphological changes, and gene expression was analyzed in heart samples. Our results showed that prolonged heat exposure caused a dramatic reduction in chicks body weight, increased lesions, and ruptured cardiac muscle fibers in the hearts, confirming that chronic heat stress damages heart tissues and causes inflammation. Our gene expression results confirmed that heat stress induces oxidative stress and inflammation in the hearts of chicks, and this is evidenced by changes in the expression of NRF2 and CAT as antioxidant factors, NFκB and LITAF as anti-inflammatory factors, and changes in the expression of Leptin as an activator of Reactive Oxygen Species production and induction of proinflammatory factors. Our study also showed that the induction of anti-inflammatory and antioxidant genes was greater upon exposure to chronic heat stress than acute heat stress. These findings confirm that chickens generally tolerate chronic heat stress better than acute heat stress.(AU)

1. Chicks
2. Hearts
3. Oxidative stress
4. Inflammation
5. Gene-expression
6. Heat stress