Low-expression Of PRKCI In The Patients With Acute Myocardial Infarction And Functional Verification Of PRKCI

Objective:We validated the low expression of PRKCI in more patients with acute myocardial infarction through the samples of peripheral white blood cells. RNA interference was used to make clear the LDL concentration of the PRKCI low expression rat myocardial cell. The meaning of the results were discussed in the end. Methods:(1) Randomly selected 20 patients with acute myocardial infarction, and another 20 normal subjects were selected as the control group. Obtained 6ml fasting venous blood of each subjects as the samples for RNA and protein extraction. The expression of PRKCI were tested in RNA level and protein level. The function of PRKCI gene was also analyzed.(2) RNA interference(RNAi) was used to knockdown the expression of endogenous PRKCI expression in rat myocardial cell line. PRKCI targeted vector and empty control vector were transfected into isolated rat myocardial cell, inverted fluorescence microscope was used to preliminarily detect the transfection efficiency after 24 hours of transfection. RNA and the total protein of myocardial cells were extracted at 48 hours after transfection. The expression of PRKCI gene was detected basing on RT-PCR and Western Blot, GAPDH andβ-actin were used as endogenuous reference gene. At the same time, the culture medium of the transfected cells were collected respectively at 5 periods as follows, before transfection, 12 hours after transfection, 24 hours after transfection, 36 hours after transfection, and 48 hours after transfection. The low density lipoprotein concentration was detected by Elisa assay.Results:(1) There were significant differences in low density lipoprotein cholesterol and high density lipoprotein cholesterol levels between the two groups. The low density lipoprotein cholesterol concentration of acute myocardial infarction group was higher, and the high density lipoprotein cholesterol concentration was lower. At RNA level, the relative expression of PRKCI gene was 0.62 ± 0.11(P=0.032) in the acute myocardial infarction group. The expression of PRKCI protein in the myocardial infarction group was significantly lower than that in control group. Pathway analysis revealed that PRKCI gene was involved in the pathway of insulin signaling pathway, platelet activation signaling pathway, Wnt signaling pathway and so on.(2) Under the inverted fluorescence microscope, the PRKCI targeted vector and control vector were successfully transfected into myocardial cell, and the efficiency of transfection had no significantly differences. At the level of RNA, the relative expression of PRKCI gene was 0.3185 ± 0.058(P=0.032). The expression of PRKCI protein was significantly decreased in PRKCI group compared with that in control group. At LDL level, the concentrations of PRKCI interference group were 4.043 ± 0.372ug/m L, 4.833 ±0.0898ug/m L, 5.324 ± 0.211ug/m L, 6.023 ± 0.131ug/m L, 5.585±0.569ug/m L. The concentrations of control group were 4.103±0.140ug/m L, 3.987 + 0.311ug/m L, 4.191 + LDL, 3.891 + 0.160ug/m L. Thus, the LDL level of PRKCI interference group increased with the time going on, and reached the peak at 30-40 hours, while the control group had no significant changes in LDL.Conclusion:PRKCI gene was low expression in the peripheral blood of patients with acute myocardial infarction. The low expression of PRKCI gene promoted LDL synthesis in H9C2 cells. The low expression of PRKCI gene lead to an increase in LDL synthesis, which may be one of the causes of acute myocardial infarction.