目的 观察高脂饮食联合持续光照处理对SD大鼠动脉硬化相关血脂指标、主动脉硬化及心功能的影响,并探讨其可能机制。方法 将32只SD雄性大鼠随机分为4组：A组：正常对照组（常规饮食+正常光照）;B组：持续光照组（常规饮食+持续光照）;C组：高脂饮食组（高脂饮食+正常光照）;D组：高脂饮食联合持续光照组（高脂饮食+持续光照）;每组各8只,记录SD大鼠体重,喂养12 w后处死大鼠。比较各组SD大鼠体重、血糖(BS)、空腹胰岛素(Ins)、胰岛素抵抗指数(HOMA-IR)、传统血脂指标[总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、甘油三酯(TG)]、动脉硬化相关血脂指标[血浆致动脉硬化指数(AIP)、动脉粥样硬化指数(AI)、脂蛋白结合指数(LCI)、非高密度脂蛋白(non-HDL-C)、总胆固醇比高密度脂蛋白胆固醇(TC/HDL-C)、低密度脂蛋白比高密度脂蛋白胆固醇(LDL-C/HDL-C)],及血浆炎症因子指标[肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)]的差异;观察各组大鼠主动脉形态、主动脉前纤维蛋白-1(profilin-1)的蛋白与基因表达差异;观察各组大鼠的心功能指标[心率(HR)、每搏量(SV)、心输出量(CO)和左室射血分数(LVEF)、左室短轴缩短率(FS)]之间的差异。结果 (1)高脂饮食联合持续光照组SD大鼠,其体重、Ins、HOMA-IR、BS、TC、LDL-C水平最高,HDL-C水平最低,其中：体重、Ins、HOMA-IR、TC均高于其它三组(均P<0.05),BS高于对照组和持续光照组(均P<0.05),LDL-C高于对照组(P<0.05),HDL-C低于对照组和持续光照组(均P<0.05)。(2)高脂饮食联合持续光照组SD大鼠,其AI、LCI、non-HDL-C、TC/HDL-C、LDL-C/HDL-C、TNF-α、IL-6水平均最高,其中：AI、non-HDL-C、TC/HDL-C、TNF-α均高于其它三组(均P<0.05),LCI、LDL-C/HDL-C、IL-6均高于对照组和持续光照组(均P<0.05),AIP高于对照组(P<0.05)。(3)主动脉形态及Profilin-1表达：高脂饮食联合持续光照组SD大鼠主动脉破坏程度最严重,管壁增厚最明显,厚度大于其它三组(均P<0.05;主动脉Profilin-1蛋白和基因的表达最高,均高于其它三组(均P<0.05)。(4)心功能：高脂饮食联合持续光照组SD大鼠,其HR最高,高于其它三组(均P<0.05);其LVEF、LVFS、SV最低：LVEF、LVFS低于其它三组(均P<0.05),SV低于对照组和高脂饮食组(均P<0.05);另,其CO低于高脂饮食组(P<0.05)。结论 高脂饮食联合持续光照处理,不仅影响SD大鼠的基础糖脂代谢水平,也使其动脉硬化相关血脂指标AI、AIP、LCI、non-HDL-C、TC/HDL-C升高,并升高炎症因子水平;破坏主动脉血管壁的完整性、增加其Profilin-1蛋白及基因表达。这可能是高脂饮食联合持续光照处理促SD大鼠动脉硬化和心功能降低的机制之一。

Objective To observe the effects of high-fat diet combined with continuous illumination on arteriosclerosis- related blood lipid indexes, aortic sclerosis and cardiac function in SD rats, and explore its possible mechanisms. Methods Thirty-two SD male rats were randomly divided into 4 groups: Group A, control group (regular diet + normal illumination); Group B, continuous illumination group (regular diet + continuous illumination); Group C, high-fat diet group (high fat diet + normal illumination); Group D, high-fat diet combined with continuous illumination group (high-fat diet + continuous illumination). Rats were fed for 12 weeks. The differences in body weight, blood glucose (BS), fasting insulin (Ins), insulin resistance index (HOMA-IR), blood lipids [total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglyceride (TG)], arteriosclerosis-related blood lipid indexes [plasma arteriosclerosis index (AIP), atherogenic index (AI), lipoprotein combine index (LCI), non-high-density lipoprotein cholesterol (non-HDL-C) , total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C), low-density lipoprotein cholesterol to high-density lipoprotein cholesterol (LDL-C/HDL-C)], and plasma inflammatory factors [tumor necrosis factor -α (TNF-α), interleukin-6 (IL) were compared. At the same time, the morphological changes of aortic sclerosis were observed, and the protein and gene expressions of profilin-1 in aorta were analyzed. Cardiac function indexes [heart rate (HR), stroke volume (SV), cardiac output (CO), left ventricular ejection fraction (LVEF) and left ventricular short axis shortening rate (LVFS)] were observed. Results (1) The rats fed with high-fat diet combined with continuous illumination had the highest levels of body weight, Ins, HOMA-IR, BS and TC, LDL-C, and the lowest level of HDL-C. Among them, the body weight, Ins, HOMA-IR and TC were all higher in group D than in the other three groups (all P<0.05), the BS was higher than the control and continuous illumination group (all P<0.05), the LDL-C was higher than the control group (all P<0.05), and the HDL-C was lower than the control and continuous illumination group (P<0.05). (2) The rats fed with high-fat diet combined with continuous illumination had the highest levels of AI, LCI, non-HDL-C, TC/HDL-C, LDL-C/HDL-C, TNF-α and IL-6. Among them, the AI, non-HDL-C, TC/HDL-C and TNF-α were higher in group D than in the other three groups (all P<0.05), the LCI, LDL-C/HDL-C, IL-6 were higher than the control and illumination group (all P<0.05), and the AIP was higher than the control group (P<0.05). (3) In rats treated with high-fat diet combined with continuous illumination, HE staining showed that the aorta was the most severely damaged, and the thickness of the aorta wall was greater than the other three groups (all P<0.05), the expressions of profilin-1 protein and gene in aorta were higher than the other three groups (all P<0.05). (4) The rats treated with high-fat diet combined with continuous illumination had the highest HR (P<0.05). LVEF, LVFS and SV were the lowest. In addition, its CO was lower than the high-fat diet group (P<0.05). Conclusion High-fat diet combined with continuous illumination not only affects glucose and lipid metabolism but also impairs the integrity of aortic vascular wall and increases the expression of aortic profilin-1 protein and gene in rats.