高盐饮食促进脑缺血后巨噬细胞浸润及CCL3表达

High salt diet promotes macrophage infiltration and CCL3 expression after cerebral ischemia

目的探讨高盐饮食(high salt diet,HSD)对脑缺血后巨噬细胞浸润及趋化因子C-C-基元配体3(chemokine C-C-Motif Ligand 3,CCL3)表达的影响。方法将实验小鼠分为正常饮食组(Normal组80只)和高盐饮食组(HSD组80只),分别喂养21 d,建立永久性大脑中动脉闭塞(permanent middle cerebral artery occlusion,pMCAO)模型,分为假手术(sham)组(40只),缺血12 h组(40只),缺血1 d组(40只)和缺血3 d组(40只);流式细胞仪检测缺血脑组织中巨噬细胞浸润情况;实时荧光定量PCR(quantitative real-time PCR,qPCR)检测缺血脑组织中CCL3 mRNA表达情况;Western blot方法检测缺血脑组织中CCL3蛋白表达情况。结果与正常饮食(Normal)组相比,HSD组小鼠缺血脑组织中巨噬细胞浸润数量明显增多[12 h:(4.98±0.46)比(8.13±0.78),t=3.475,P_(12h)<0.05;1d:(7.30±0.89)比(13.41±0.66),t=5.519,P_(1d)<0.05;3d:(14.66±0.80)比(17.56±1.24),t=1.953,P_(3d)>0.05];与Normal组相比,HSD组小鼠缺血脑组织中CCL3 mRNA表达明显增多[12h:(7.10±0.24)比(14.09±0.92),t=6.302,P_(12h)<0.05;1d:(5.75±0.41)比(9.60±1.42),t=3.773,P_(1d)<0.05;3d:(4.37±0.37)比(7.36±0.77),t=4.560,P_(3d)<0.05],12 h时表达最高;CCL3蛋白表达明显增多[12 h:(0.13±0.01)比(0.24±0.02),t=4.230,P_(12h)<0.05;1d:(0.24±0.03)比(0.36±0.03),t=3.207,P_(1d)<0.05;3d:(0.14±0.02)比(0.25±0.02),t=4.381,P_(3d)<0.05],1d时表达最高。结论高盐饮食促进脑缺血后巨噬细胞浸润,促进CCL3的表达。

Objective To investigate the effect of high salt diet(HSD)on macrophage infiltration and the expression of chemokine C-C-Motif Ligand 3(CCL3)after cerebral ischemia.Methods The mice were divided into a normal diet group(n=80)and a high-salt diet group(n=80),these mice were fed for 21 days to establish a permanent middle cerebral artery occlusion(pMCAO)model,which was divided into four groups:sham group(n=40);12 h group(n=40);1 d group(n=40);3 d group(n=40).The infiltration of macrophages in ischemic brain tissue was detected by flow cytometry;The expression of CCL3 mRNA in ischemic brain tissue was detected by quantitative real-time PCR(qPCR);The expression of CCL3 protein in ischemic brain tissue was detected by Western blot.Results Compared with the Normal group,the number of macrophage infiltration in the ischemic brain tissue of mice in the HSD group was significantly increased[12 h:(4.98±0.46)vs(8.13±0.78),t=3.475,P_(12h)<0.05;1d:(7.30±0.89)vs(13.41±0.66),t=5.519,P_(1d)<0.05;3d:(14.66±0.80)比(17.56±1.24),t=1.953,P_(3d)>0.05];Compared with the Normal group,the expression of CCL3 mRNA in the ischemic brain tissue of mice in the HSD group was significantly increased[12 h:(7.10±0.24)vs(14.09±0.92),t=6.302,P_(12h)<0.05;1d:(5.75±0.41)vs(9.60±1.42),t=3.773,P_(1d)<0.05;3d:(4.37±0.37)vs(7.36±0.77),t=4.560,P_(3d)<0.05],the highest expression was found in the 12 h group;The expression of CCL3 protein was also significantly increased[12 h:(0.13±0.01)vs(0.24±0.02),t=4.230,P_(12h)<0.05;1d:(0.24±0.03)vs(0.36±0.03),t=3.207,P_(1d)<0.05;3d:(0.14±0.02)vs(0.25±0.02),t=4.381,P_(3d)<0.05],and the highest expression was found in the 1d group.Conclusion HSD increased the macrophages infiltration and promoted the expression of CCL3 after cerebral ischemia.