载脂蛋白B-100亚单位多聚肽免疫对ApoE-/-小鼠血脂水平和动脉粥样硬化斑块面积影响的研究

Effect of apolipoprotein B-100 subunit poly peptide immune on levels of lipid and areas of atherosclerotic plaque in ApoE-/-mice

摘要:

目的：探讨载脂蛋白B-100（apolipoprotein B-100，apoB-100）亚单位多聚肽免疫对载脂蛋白E基因缺陷（ApoE-/-）小鼠动脉粥样硬化（atherosclerosis，AS）的影响。 方法：将ApoE-/-小鼠随机分成3组：模型对照组（A组）、apoB-100亚单位混合组（B组）、apoB-100全肽组（C组），每组12只。B、C组小鼠给予相应多肽进行皮下免疫注射，A组小鼠皮下注射等体积的生理盐水。所有小鼠高脂喂养25周后全部处死，ELISA法检测特异性IgG抗体滴度，生化仪检测各组小鼠血清总胆固醇（total cholesterol，TC）、甘油三酯（triglyceride，TG）、低密度脂蛋白胆固醇（low density lipoprotein cholesterol，LDL-C）和高密度脂蛋白胆固醇（high density lipoprotein cholesterol，HDL-C）水平，油红O染色后检测主动脉AS粥样斑块面积及其与管腔面积的比值。 结果：（1）B组和C组首次免疫后平均抗体滴度均高于免疫前（1∶962.5 vs. 1∶0.121，t= 9.522，P=0.000；1∶1108.3 vs. 1∶0.121，t=7.531，P=0.000），差异均有统计学意义；B组和C组二次免疫后平均抗体滴度均高于免疫前（1∶3 582.9 vs. 1∶0.121，t=11.972，P=0.000；1∶3 824.8 vs. 1∶0.121，t= 8.220，P=0.000），差异均有统计学意义；B组和C组首次二次免疫后平均抗体滴度均高于首次免疫，差异均有统计学意义（t=3.522，P=0.009；t=3.179，P=0.007）。（2）B组的血清TC（16.03 ± 1.49）、TG（1.72 ± 0.12）、LDL-C（2.15±0.16）水平均低于A组（23.44±1.72、3.01±0.26、3.04±0.28），HDL-C水平（2.87±0.17）高于A组（1.82 ± 0.11），差异均有统计学意义（t=3.289，P=0.027；t=2.766，P=0.031；t=3.025，P=0.029 t=4.187，P=0.001）；C组血清TC（17.94 ±1.55）、TG（1.88 ± 0.15）、LDL-C（1.97±0.14）水平均低于A组，HDL-C水平（3.01±0.39）高于A组，差异均有统计学意义（t=4.209，P=0.001；t=5.116，P=0.000；t=6.025，P=0.000；t=3.157，P=0.026）。（3）B组和C组动物较A组AS病变程度轻，斑块面积与管腔面积比值小于A组（4.59±1.41）vs.（17.6 ± 5.36），t=3.465，P=0.021；（3.87 ± 2.05）vs.（17.6±5.36），t=2.992，P=0.030），差异有统计学意义。结论：apoB-100亚单位多聚肽可能通过调节ApoE-/-小鼠血脂代谢，影响ApoE-/-小鼠动脉粥样硬化病变的形成。

Abstract:

Objective：To observe the influence of apolipoprotein B-100（apoB-100） subunit poly peptide immune on atherosclerosis（AS） of ApoE-/-mice. Methods：ApoE-/-mice were randomly divided into three groups：group A（model control group） and group B（apoB-100 p45，apoB-100 p143 and apoB-100 p210 mixture group），group C（apolipoprotein B-100 intact peptide group），with 12 mice in each group. Mice of groups B and C were given polypeptide subcutaneous immunization while those in group A was given normal saline with same volume. All animals were executed after 25 weeks’ high fat diet. Enzyme linked immunosorbent assay was performed to detect specific IgG antibody. Total cholesterol（TC），triglyceride（TG） and low density lipoprotein cholesterol（LDL-C） high-density lipoprotein cholesterol（HDL-C） levels in serum of experimental mice were detected by biochemical analyzer. The ratio of AS plaque area against lumen area was measured by image analysis software after HE staining. Results：（1）After the first immu－nization，group B and group C had significant higher level of antibody than before（1∶962.5 vs. 1∶0.121，t=9.522，P=0.000；1∶1108.3 vs. 1∶0.121，t=7.531，P=0.000）. After the second immunization，group B and group C got significant higher antibody than before（1∶3582.9 vs. 1∶0.121，t=11.972，P=0.000；1∶3824.8 vs. 1∶0.121，t=8.220，P=0.000）. After the second immunization，group B and group C got higher level of antibody than first immunization（t=3.522，P=0.009；t=3.179，P=0.007）. （2）Serum TC（16.03±1.49），TG（1.72±0.12） and LDL-C（2.15±0.16） were significantly lower in group B than in group A（23.44±1.72，3.01±0.26，3.04±0.28） while HDL-C levels（2.87±0.17） was significantly higher in group B than in group A（1.82±0.11）（t=3.289，P=0.027；t=2.766，P=0.031；t=3.025，P=0.029，t=4.187，P=0.001）. TC（17.94±1.55），TG（1.88±0.15） and LDL-C（1.97±0.14） were significantly lower in group C than in group A while HDL-C levels（3.01±0.39） was significantly higher in group C than in group A（t=4.209，P=0.001；t=5.116，P=0.000；t=6.025，P=0.000；t=3.157，P=0.026）. （3）AS sever－ity was lighter in group B and group C than in group A and ratio of AS plaque area against lumen area was lower in group B and group C than in group A（4.59±1.41 vs. 17.6±5.36，t=3.465，P=0.021；3.87±2.05 vs. 17.6±5.36，t=2.992，P=0.030）. Conclusion：apoB-100 subunit poly peptide immune may regulate the formation of AS by adjusting the blood lipid metabolism of ApoE-/- mice.