间断寒邪暴露对ApoE-/-动脉粥样硬化模型小鼠血脂代谢及单核巨噬细胞表达的影响

目的探究间断寒邪暴露对载脂蛋白E敲除(ApoE^-/-)动脉粥样硬化小鼠血脂代谢及炎症的影响。方法将36只ApoE^-/-小鼠随机分为常温对照组和间断寒邪暴露组,每组18只。所有小鼠均高脂饲养,不限食水。前8周所有小鼠均饲养在常温环境,间断寒邪暴露组于8周后开始每天饲养于4℃低温环境中6 h,常温对照组不予处理。观察记录各组小鼠进食量与体质量变化。比较两组小鼠脂肪重量、血脂指标,采用流式细胞术检测肩胛间区、腹股沟、附睾部位脂肪组织中单核巨噬细胞M1、M2表达的占比及M1/M2比值。结果两组小鼠进食量比较差异无统计学意义(P>0.05),但间断寒邪暴露组体质量较常温对照组降低(P<0.05);两组小鼠脂肪组织质量比较差异无统计学意义(P>0.05)。间断寒邪暴露组小鼠三酰甘油(TG)较常温对照组降低(P<0.05),总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)比较差异均无统计学意义(P>0.05)。间断寒邪暴露组小鼠肩胛间区棕色脂肪组织中单核巨噬细胞M1/M2明显降低(P<0.01),M1型占比降低,M2型占比升高,但差异均无统计学意义(P>0.05);腹股沟及附睾白色脂肪组织中单核巨噬细胞M1表达降低,M2表达增高,M1/M2降低,但差异均无统计学意义(P>0.05)。结论间断寒邪暴露可以降低动脉粥样硬化小鼠TG水平,并减轻小鼠肩胛棕色脂肪组织代谢性炎症。

Effects of Intermittent Cold Exposure on Lipid Metabolism and Inflammation in ApoE-/- Atherosclerosis Mice

Objective To investigate the effects of intermittent cold exposure on lipid metabolism and inflammation in atherosclerotic mice.Methods Thirty-six ApoE^-/- mice were randomly divided into normal temperature group and intermittent cold exposure group,with 18 mice in each group.All mice were fed high-fat diet with unlimited water supply.In the first 8 weeks,all mice were raised in normal temperature environment.The mice in intermittent cold exposure group were raised in a low temperature environment of 4℃for 6 h per day from the 9th week,and the mice in normal temperature group were not treated.Food intake and body weight of each group were observed and recorded.After intermittent cold exposure,the fat weight and blood fat of mice in each group were compared.Flow cytometry was used to detect the proportion and M1/M2 ratio of mononuclear macrophage expression in the adipose tissue of the interscapular area,groin and epididymis.Results There was no significant difference in food intake between the two groups(P>0.05),but the body weight of mice in intermittent cold exposure group was lower than that of normal temperature group(P<0.05).There was no significant difference in fat tissue quality between the two groups(P>0.05).The blood triglyceride(TG)in intermittent cold exposure group was lower than that in normal temperature group(P<0.05),but the differences of cholesterol(TC),high-density lipoprotein cholesterol(HDL-C),and low-density lipoprotein cholesterol(LDL-C)were not statistically significant(P>0.05).In intermittent cold exposure group,the M1/M2 ratio of mononuclear macrophage in the brown adipose tissue of the interscapular area decreased(P<0.01),and the proportion of M1 type macrophages decreased,while the proportion of M2 type macrophages increased,but the difference was not statistically significant(P>0.05).In white adipose tissue of groin and epididymis,M1 type macrophages expression decreased,M2 type macrophages expression increased,and M1/M2 ratio decreased,but the difference was not statistically significant(P>0.05).Conclusion Intermittent cold exposure can reduce the level of TG and reduce the metabolic inflammation of the brown adipose tissue of the scapular in atherosclerotic mice.