Rhythm changes of clock genes, apoptosis-related genes and atherosclerosis-related genes in apolipoprotein E knockout mice.
BACKGROUND
Acute myocardial infarction and stroke occur more frequently in the morning, suggesting a role of the circadian clock in these main causes of death, secondary to atherosclerosis.


OBJECTIVE
To investigate the expression of clock genes, apoptosis-related genes and atherosclerosis-related genes in the process of atherosclerosis.


METHODS
Apolipoprotein E knockout (ApoE-/-) mice were used to establish animal models of early and advanced atherosclerosis. Real-time polymerase chain reaction, Western blotting and microarray assays were used to detect the expression of clock genes, apoptosis-related genes and atherosclerosis-related genes.


RESULTS
Clock genes in ApoE-/- and C57BL/6J mouse hearts exhibited daily oscillations at the messenger RNA level. However, the expression level and rhythm between ApoE-/- and C57BL/6J mice were significantly different. Moreover, the changes became more significant as atherosclerosis developed. c-Myc and p53 genes exhibited circadian expression in C57BL/6J mice at messenger RNA and protein levels. However, the rhythm in ApoE-/- mice disappeared completely. Bcl-2 and Bax did not show daily rhythm in either strain of mouse. Aside from apoptosis-related genes, several atherosclerosis-related genes expressed time-dependent behaviour in C57BL/6J mice but not in ApoE-/- mice.


CONCLUSIONS
Rhythm changes of clock genes, apoptosis-related genes and atherosclerosis-related genes may play important roles in atherosclerosis and its complications.
Xu
Chen
C
Department of Physiology and Pathophysiology, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China.
Lu
Chao
C
Hua
Luchun
L
Jin
Huiming
H
Yin
Lianhua
L
Chen
Sifeng
S
Qian
Ruizhe
R
D000818:Animals; D001057:Apolipoproteins E / Q000235:genetics*; D017209:Apoptosis / Q000235:genetics*; D050197:Atherosclerosis / Q000235:genetics*; D002940:Circadian Rhythm / Q000235:genetics*; D004195:Disease Models, Animal; D015870:Gene Expression; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout
D001057:Apolipoproteins E