Expression of autophagy related gene 5 and cyclin E in coronary heart disease and its clinical significance.

OBJECTIVES

To explore the expression of autophagy related genes 5 (ATG5) and cyclin E in coronary heart disease (CHD) and its clinical significance.

METHODS

From April 2018 to August 2018, 80 patients diagnosed with CHD in the Second Xiangya Hospital, Central South University were selected as an observation group, and another 80 healthy subjects were selected as a control group. The expression of ATG5 and cyclin E mRNA in nucleate cells and the plasma protein in the 2 groups were detected and analyzed. The model of macrophage-derived foam cells induced by oxidized low density lipoprotein (ox-LDL) was used to simulate atherosclerosis. The proliferation of macrophage- derived foam cells and the protein levels of ATG5 and cyclin E induced by ox-LDL at different concentrations were examined.

RESULTS

Compared with the control group, the levels of ATG5 mRNA and protein in the blood in the observation group were decreased, and the cyclin E mRNA and protein levels were increased, there were statistically difference (both <0.05). Receiver operating characteristic (ROC) curve showed that the area under curve (AUC) of ATG5 mRNA, cyclin E mRNA, ATG5 protein and cyclin E protein were 0.739, 0.780, 0.671 and 0.807, respectively. Pearson analysis showed that the ATG5 mRNA was negatively correlated with the cyclin E mRNA (=-0.734, <0.05),while the plasma ATG5 protein was negatively correlated with the plasma cyclin E protein (=-0.746, <0.05). Macrophage-derived foam cell model induced by ox-LDL showed that the proliferation of foam cells and the expression levels of cyclin E protein were increased in a concentration and time-dependent manner, and the expression levels of ATG5 protein were decreased in a concentration-dependent manner.

CONCLUSIONS

The levels of ATG5 mRNA and protein are lowly expressed while the levels of cyclin E mRNA and protein are highly expressed in the patients with CHD.The ATG5 protein levels are lowly expressed in ox-LDL-treated macrophage-derived foam cells while the cyclin E protein levels are highly expressed in ox-LDL-treated macrophage-derived foam cells. Based on these observations, we conclude that ATG5 inhibits the degradation of the cyclin E and promotes the proliferation of macrophages, involving in the occurrence and development of CHD.