Acute Heat Stress Alters the Expression of Orexin System in Quail Muscle

Abstract

Accumulating evidences indicate that the hypothalamic neuropeptide orexins or hypocretins are involved in stress-induced responses in mammals. Recently, we found that orexin is expressed and secreted from avian muscle cells, however its regulation is still unknown. In this study, we investigated the effect of heat and oxidative stress, the most challenging stressors in poultry production, on the expression of orexin system in quail muscle tissues and myoblast cell lines. Four week-old genetically selected susceptible and resistant Japanese quail (Coturnix coturnix Japonica) lines were exposed to acute heat stress (HS, 37°C for 1.5 h) or maintained at thermoneutral conditions (24°C). Quail myoblast (QM7) cell line was exposed to heat stress (45°C) for 0.5, 1, 2, or 4 h. The control cells were maintained at 37°C. The cells were also treated with several doses of hydrogen peroxide (H2O2, 10–200 μM) or 4-Hydroxynonenal (4-HNE, 10–30 μM) as oxidative stress. Untreated cells were used as controls. Acute HS significantly induced the expression of HSP70 and down-regulated orexin system in both quail muscle tissue and QM7 cells. Similarly, H2O2 but not 4-HNE treatment significantly increased HSP70 protein levels and dysregulated the expression of orexin and its related receptors in a dose-dependent manner in QM7 cells. Transient overexpression of HSP70 down-regulated the expression of orexin system in QM7 cells. Taken together, these data indicate that orexin may be a key player in stress response in avian muscle by demonstrating that heat and oxidative stress alter the expression of orexin system in quail muscle. This effect might be mediated through HSP70. Unraveling the upstream regulators and downstream effectors of orexin in avian muscle merits further in depth investigations.

Keel fracture changed the behavior and reduced the welfare, production performance, and egg quality in laying hens housed individually in furnished cages

“…We speculated that this decrease in feeding may be related to the impaired mobility in hens and stress induced by keel fractures. Some researchers have reported that negative emotions, heat, and oxidative stress downregulate the expression of avian orexin and orexin receptors genes, which may inhibite the feeding motivation ( Greene et al., 2016 , Nguyen et al., 2017 ). Likewise, our previous study has found that keel fracture causes stress response and inhibits the gene expression of orexin and its receptors ( Wei et al., 2019 ).…”

Intestinal Barrier Integrity in Heat-Stressed Modern Broilers and Their Ancestor Wild Jungle Fowl

“…Due to their high metabolic activity and lack of sweat glands, modern broilers are particularly sensitive to heat stress. The strong adverse effects of heat stress on growth, feed intake, feed efficiency, meat yield and quality, welfare, and mortality are well documented in broilers (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Emerging evidence indicates that heat stress alters also the gut morphometry (lower crypt depth, mucous area, and villus height) which in turn affect nutrient absorption (21).…”

Sprinkler Technology Improves Broiler Production Sustainability: From Stress Alleviation to Water Usage Conservation: A Mini Review

“…This reduction in blood (oxygen) and energy supplies result in stress and damage to many internal organs. The strong adverse effects of heat stress on poultry production, welfare, meat quality, and mortalities are well-documented and elegantly reviewed elsewhere (8)(9)(10)(11)(12)(13)(14)(15)(16).…”