Effects Of Nighttime Illumination On Cellular Homeostasis In Zebra Finch

Night lighting is a major environmental feature that accelerates the process of urbanization.Night lighting disturbs the normal circadian rhythms of animals.Birds,as the main wild animal groups living in cities,as circadian vertebrates,their circadian rhythms are very similar to humans.Night lighting induces disturbances in the circadian rhythm of birds,which in turn leads to changes in behavior and physiology.Cell homeostasis is the basic and necessary condition for the survival of the body.At present,at the cellular level,the mechanism by which the level of gene expression affects night lighting on the homeostasis of avian cells is still unclear.Based on this,this study took Zebra finches(Taeniopygia guttata)as an example,and compared Zebra finches blood cells clock gene expression,blood cells oxidative stress level,blood cells apoptosis and anti-apoptosis,and blood cells energy metabolism under different photoperiod.The level of change is expected to provide a scientific basis for in-depth understanding of the effects of night lighting on the homeostasis of bird blood cells.The main conclusions of this paper are as follows:1.Different photoperiod conditions affect the expression of circadian clock genes in blood cells of Zebra finches.The longer the lighting time,the higher the relative expression levels of clock genes Clock,Bmal-1 and Per-2,indicating that night light causes changes in the expression of bird clock genes,which may lead to changes in bird behaviors and have negative impact to birds.2.Different photoperiod conditions affect the oxidative stress level of Zebra finches blood cells.With the increase of light duration,the activities of catalase(CAT),superoxide dismutase(SOD)and glutathione peroxidase(GPx)increased the antioxidant capacity,suggesting that nighttime lighting increased the oxidative stress of Zebra finches,changed their oxidative state,and led to the disturbance of cell homeostasis in birds.3.Different photoperiod conditions affect the balance of apoptosis and anti-apoptosis in Zebra finches blood cells.With the increase of light duration,the expression of Caspase-3 in Zebra finches was inhibited by the high expression of Bcl-2,HSP70 and HSP90 genes,suggesting that nighttime lighting led to the imbalance of apoptosis and anti-apoptosis,which was detrimental to cell homeostasis in birds.4.Different photoperiod conditions affect blood cells energy metabolism of Zebra finches.As light increases,the Zebra finches blood cells energy metabolism regulation genes expressed in high AMPKa and SIRT-1,provide the body with enough ATP,suppressed PFK expression,suggest that lighting in energy metabolism regulating gene expression changes,resulting in birds cells at a high state of oxidation decomposition,and thus damage cells homeostasis.