辛伐他汀消退老年载脂蛋白E基因敲除小鼠动脉粥样硬化斑块的观察

目的观察辛伐他汀对高脂喂养的老年载脂蛋白E(apoE)基因敲除小鼠动脉粥样硬化(AS)斑块的作用。方法选取高脂喂养的60周龄雄性aopE基因敲除小鼠30只,随机分为辛伐他汀高剂量组、辛伐他汀低剂量组和模型组,每组10只,分别每天予以辛伐他汀20mg/kg、辛伐他汀5mg/kg和等量生理盐水灌胃,连续灌胃8周后,取主动脉窦部做病理检测。冷冻切片光镜下观察AS斑块病理情况,免疫组织化学染色观察骨桥蛋白、α肌动蛋白的表达。vonkossa染色观察斑块钙化情况。结果与模型组比较,辛伐他汀高、低剂量组apoE基因敲除小鼠的血清TC和LDL-C水平明显降低(P<0.05),斑块面积占管腔面积比、斑块内钙化染色面积明显减少(P<0.05)。结论辛伐他汀可明显降低老年apoE基因敲除小鼠的血清TC和LDL-C水平,消退AS斑块的大小及其钙化。     

奥美沙坦对动脉粥样硬化大鼠斑块稳定性的影响

目的 观察奥美沙坦对动脉粥样硬化(AS)大鼠斑块中基质金属蛋白酶-9(MMP-9)、血管平滑肌细胞、巨噬细胞数量的影响,探讨其稳定AS斑块的作用及可能机制.方法 应用高脂饮食建立AS大鼠模型,将16只健康雄性Wistar大鼠随机分为两组,每组8只.模型组饲喂含1%胆固醇、5%猪油的高脂饲料;奥美沙坦组饲喂含1%胆固醇、5%猪油高脂饲料加奥关沙坦10mg/(kg·d),连续用药3个月.免疫组化法检测AS斑块中MMP-9的蛋白表达水平及粥样斑块中血管平滑肌细胞和巨噬细胞数量.结果 免疫组化显示,奥美沙坦组与模型组相比MMP-9蛋白表达显著减少(P<0.05),平滑肌细胞数量显著增加(P<0.05),巨噬细胞数量明显降低(P<0.05).结论 奥美沙坦可通过下调MMP-9的水平,增加斑块中平滑肌细胞数量,减少斑块内巨噬细胞的数量来稳定AS斑块.     

普罗布考对兔动脉粥样硬化模型C反应蛋白水平的影响及其与斑块稳定性的关系

目的观察兔动脉粥样硬化(AS)模型中C反应蛋白(CRP)的水平与斑块稳定性之间的关系,及普罗布考对CRP水平的影响。方法 20只新西兰大白兔采用随机数字表法分为正常对照组(n=6)、高脂饮食组(n=8)和普罗布考组(n=6)。对照组予普通饲料喂养,高脂饮食组和普罗布考组予高脂饲料喂养。4周后高脂饮食组和普罗布考组行髂动脉内膜球囊损伤术。术后普罗布考组每只大白兔加用普罗布考1g/d口服,10周末取血测血清CRP水平,之后处死动物取损伤处动脉,用HE染色观察动脉病理形态学变化。结果高脂饮食组动脉可见典型的AS斑块形成,普罗布考组无典型斑块形成,内膜增厚较为明显;与高脂饮食组比较,普罗布考组血清CRP水平较低[(8.10±1.02)mg/L比(11.35±2.32)mg/L,P<0.05]。结论 CRP在兔AS模型的表达水平明显增加,与斑块的不稳定性有关,普罗布考有一定的抑制兔AS模型血清CRP表达的作用。     

心悦胶囊对2型糖尿病大鼠血糖及血脂代谢的影响

目的观察心悦胶囊对实验性2型糖尿病大鼠血糖及血脂代谢的影响。方法将Wistar大鼠随机分为为正常组、模型组、二甲双胍组及心悦胶囊低、中、高剂量组,正常组及模型组均每日灌胃0.5%羧甲基纤维素钠2 ml/kg,心悦胶囊三个剂量组分别每日灌胃150、300、600 mg/kg,二甲双胍组每日灌胃20 mg/kg,连续给药4 w。采用高脂饮食伴小剂量链脲佐菌素55 mg/kg建立大鼠实验性2型糖尿病模型,每周测空腹血糖1次,4 w后检测肝糖原、胰岛素、C-肽、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、游离脂肪酸(FFA)、丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性。结果与模型组比较,心悦胶囊中、高剂量组于第2、3、4周空腹血糖明显降低(P<0.05或P<0.01),4 w后肝糖原、胰岛素及C-肽含量均明显升高(P<0.05),LDL-C、TC、TG、TC/HDL-C、LDL-C/HDL-C、FFA及MDA水平均显著降低(P<0.05或P<0.01),HDL-C含量及SOD活性均显著升高(P<0.05或P<0.01)。结论心悦胶囊能明显降低2型糖尿病大鼠空腹血糖,改善血脂代谢紊乱,并具有抗氧化作用。     

阿司匹林对小型猪动脉粥样硬化的影响

目的探讨阿司匹林对早期动脉粥样硬化的干预作用。方法健康小型猪22头,随机分为对照组(n=6):给予正常猪饲料;高脂组(n=8):给予3%胆固醇高脂饮食;阿司匹林组(n=8):给予3%胆固醇高脂饮食 阿司匹林150 mg/d。高脂饮食4个月和6个月时,每组随机处死一半,定量测量动脉粥样硬化斑块厚度和斑块面积。结果3.0%胆固醇高脂饮食4个月就可以引起小型猪明显的动脉粥样硬化。高脂饮食4个月时,高脂组冠状动脉斑块厚度和截面积分别为107.2±45.7μm和0.113±0.05 mm2;阿司匹林组主动脉粥样硬化面积无明显减少,冠状动脉斑块厚度和截面积分别为74.2±24.7μm和0.093±0.05 mm2,与高脂组相比无统计学差异。高脂饮食6个月时,高脂组冠状动脉动脉粥样硬化斑块厚度为152.9±86.1μm、斑块/中膜厚度比0.85±0.49、斑块截面积为0.188±0.207 mm2、内膜/中膜面积比0.235±0.249;阿司匹林组主动脉粥样硬化面积明显减少,冠状动脉粥样硬化斑块厚度(47.8±19.8μm)、斑块/中膜厚度比(0.33±0.09)、斑块截面积(0.017±0.012 mm2)、内膜/中膜面积比(0.030±0.019),均明显低于高脂组(P<0.05或P<0.01)。结论阿司匹林对早期动脉粥样硬化有抑制作用。     

瑞舒伐他汀对ApoE-/-小鼠动脉粥样斑块中凋亡相关蛋白的影响

目的观察瑞舒伐他汀对Apo E-/-小鼠动脉粥样硬化斑块凋亡相关蛋白Bcl-2和Caspase-3表达的影响。方法 10只C57小鼠作为对照组,给予普通饮食,同品系22只Apo E-/-小鼠随机分为模型组(n=11)、干预组(n=11),高脂喂养8 w后,干预组给予瑞舒伐他汀悬液灌胃,模型组给予等量生理盐水。继续喂养12 w后所有老鼠处死,全自动生化仪检测血清血脂,光学显微镜观察各组小鼠主动脉斑块形态及面积,免疫组化法检测动脉粥样斑块Bcl-2和Caspase-3蛋白的表达。结果与对照组相比较,模型组总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)明显升高(P0.05),高密度脂蛋白胆固醇(HDL-C)明显降低(P0.05);主动脉可见明显粥样斑块;Bcl-2表达明显减少,Caspase-3表达明显增多(P0.05)。与模型组比较,TC、TG、LDL-C明显降低(P0.05);干预组小鼠动脉粥样斑块面积减小(P0.05),Bcl-2表达明显增多,Caspase-3表达明显减少(P0.05)。结论高脂饮食可引起Apo E-/-小鼠主动脉凋亡相关蛋白Bcl-2和Caspase-3的变化,瑞舒伐他汀可以通过上调Bcl-2、下调Caspase-3的表达,抑制Apo E-/-小鼠动脉粥样硬化斑块的进展。     

吡格列酮对实验性动脉粥样硬化大鼠血脂水平的影响及临床意义

目的观察吡格列酮对高脂饮食诱导动脉粥样硬化模型大鼠血脂水平的影响,并探索其临床意义。方法设清洁型SD大鼠26只,随机分为对照组(n=9)、高脂饮食组(n=17),高脂饮食组喂养12周后再随机分为模型组(n=8)和吡格列酮组(n=9),分别给予蒸馏水、蒸馏水(1.5ml/100g)和吡格列酮10mg/(kg·d)灌胃,1次/d,同时继续高脂饮食,干预4周后,检测各组血脂水平并观察主动脉病理形态学改变。结果高脂饮食喂养12周后,与对照组相比,模型组和吡格列酮组三酰甘油(TG)、总胆固醇(TC)显著升高(P<0.01)。给药干预4周后,吡格列酮组干预后TG、TC、低密度脂蛋白胆固醇(LDL-C)较干预前明显降低(P<0.01),与模型组比较,吡格列酮组TG、TC水平明显降低(P<0.01)。且可减轻高脂饮食诱导的主动脉内膜增厚和平滑肌细胞增殖。结论吡格列酮可改善高脂血症大鼠血脂水平,延缓主动脉粥样硬化病理改变,提示吡格列酮的抗动脉粥样硬化作用可能部分归于血脂改善效应。     

普罗布考对高密度脂蛋白亚组分与抗氧化功能的影响

目的研究普罗布考对动脉粥样硬化(AS)兔HDL亚组分及氧化功能的影响,探讨普罗布考抗AS机制。方法选择18只新西兰大白兔随机分为:对照组6只,饲以普通饲料;AS组6只,饲以高脂饲料;普罗布考组6只,饲以高脂饲料基础上给予普罗布考400 mg/(kg·d)。1 2周后酶法检测血脂;分光光度计法检测血清对氧磷酶1(PON1)活性;采用化学沉淀法检测HDL_2/HDL;组织切片和HE染色检测主动脉内膜中层厚度(IMT)和动脉斑块/血管面积。结果实验12周后,与AS组比较,普罗布考组血清TC、LDL-C、HDL-C水平明显下降(P0.01);PON1活性明显升高(P=0.000);HDL_2/HDL明显降低(P=0.000),主动脉IMT明显减小(P=0.000),斑块面积/血管腔面积明显降低(P=0.002)。结论普罗布考通过提高PON1活性,降低HDL_2/HDL而改善HDL功能,减少主动脉IMT及斑块面积/血管腔面积,延缓AS进展。     

卡托普利、缬沙坦对兔动脉粥样硬化斑块的干预作用

目的观察高胆固醇饮食造成兔大动脉粥样斑块形成过程中卡托普利和缬沙坦对大动脉粥样斑块形成的干预作用。方法30只健康雄性新西兰兔随机分为高脂饮食组(A组),高脂饮食加卡托普利组(B组),高脂饮食加缬沙坦组(C组)和对照组(D组)喂养10周后,行超声检测腹主动脉内膜中膜的厚度。并行病理观察血管内膜以及血管内皮细胞情况。结果A组腹主动脉壁粥样斑块形成,血管内膜增厚;B组和C组血管壁有少量粥样斑块形成,血管内膜增厚均较A组明显减轻(P<0.01)。结论卡托普利和缬沙坦具有抗高胆固醇血症致动脉壁粥样斑块形成的确切效果。     

异甘草素通过调节自噬作用减轻动脉粥样硬化大鼠斑块形成

目的 探讨异甘草素(ISL)通过调节自噬作用减轻动脉粥样硬化(AS)大鼠斑块形成。方法 维生素D3联合高脂饮食法建立AS模型，按随机数字法分为模型组、ISL组、ISL+自噬抑制剂组、自噬激活剂组各10只。ISL组灌胃50 mg/kg ISL,ISL+自噬抑制剂组在ISL基础上腹腔注射100 mg/kg自噬抑制剂3-甲基腺嘌呤(MA),自噬激活剂组腹腔注射1 mg/kg自噬激活剂西罗莫司。正常组喂基础饲料相同天数。连续4 w。超声仪检测各组动脉管腔动脉后壁内膜-中层厚度(IMT)、斑块面积(S)情况；全自动生化分析仪检测血清中总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)含量；苏木素-伊红(HE)染色检测颈动脉病理情况；透射电镜观察颈动脉超微结构；Western印迹检测颈动脉中微管相关蛋白1轻链3Ⅱ型(LC3Ⅱ)、自噬相关蛋白(Beclin1)蛋白情况。结果 模型组出现动脉管壁明显增厚现象，管腔中可见明显的粥样或纤维斑块，内膜中可见白色条纹或黄白色斑块，斑块中自噬体、脂滴有所增多；ISL组和自噬激活剂组动脉壁弹性明显恢复，管腔内脂斑沉淀明显减少，斑块内可见明显的自噬...     

Attenuation of the development of hypercholesterolemic atherosclerosis by thymoquinone

Thymoquinone (TQ), derived from Nigella sativa seed, is an antioxidant. The present study investigated whether TQ attenuates the development of atherosclerosis, and/or reduces the serum lipid levels and oxidative stress in rabbits. New Zealand white female rabbits were assigned to four groups of six animals each: group I, control; group II, 1% cholesterol diet; group III, 1% cholesterol plus TQ (10 mg/kg/day; through a nasogastric tube) diet; and group IV, 1% cholesterol plus TQ (20 mg/kg/day; through a nasogastric tube) diet. Blood samples were collected at baseline and after four and eight weeks on the experimental diets for measurement of serum lipids, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TC/HDL-C ratio and oxidative stress biomarkers (malondialdehyde [MDA] and protein carbonyls). At the end of the eight weeks, the aorta was removed for the assessment of atherosclerotic changes, MDA and protein carbonyls. Group II animals developed atherosclerosis (45%±11% of the intimal surface of aorta was covered with atherosclerotic plaques), which was associated with an increase in the serum TC, TG, LDL-C, HDL-C, TC/HDL-C, MDA and protein carbonyls. In group III, TQ decreased serum TC, LDL-C, MDA and protein carbonyls by 26%, 29%, 85% and 62%, respectively, and aortic MDA by 73%, which was associated with a 40% reduction of the development of aortic atherosclerosis. The higher dose of TQ in group IV had effects similar to the lower dose (group III), except that this dose further decreased serum TG. It is concluded that TQ attenuates hypercholesterolemic atherosclerosis and this effect is associated with a decrease in serum lipids and oxidative stress.     

Hypocholesterolemic and antiatherosclerotic effect of flax lignan complex isolated from flaxseed

Hypercholesterolemia, low HDL-C and oxygen radicals have been implicated in the development of atherosclerosis. Lignan complex isolated from flaxseed contains secoisolariciresinol diglucoside (SDG), 3-hydroxy-3methylglutaric acid (HMGA) and cinnamic acids. SDG and cinnamic acids are antioxidants, and HMGA is a hypocholesterolemic agent. Antioxidants are known to reduce hypercholesterolemic atherosclerosis. The objectives of this study were to determine if lignan complex reduces (i) serum cholesterol, (ii) oxidative stress, and (iii) atherosclerosis in hypercholesterolemic rabbits. Rabbits were assigned to four groups: Group I, control; Group II, lignan complex control (lignan complex, 40 mg/kg body weight daily orally); Group III, 0.5% cholesterol; Group IV, 0.5% cholesterol diet+lignan complex, (40 mg/kg body weight daily orally). Blood samples were collected before (time 0) and after 1 and 2 months of experimental diets for measurement of serum triglycerides (TG), total cholesterol (TC), LDL-C, HDL-C and serum malondialdehyde (MDA), a lipid peroxidation product. At the end of the protocol, the aorta was removed for measurement of atherosclerotic plaques, MDA and aortic tissue chemiluminescence (Aortic CL), a marker of antioxidant reserve. Rabbits in Group III developed atherosclerosis (50.84+/-6.23% of the intimal surface of the aorta was covered with atherosclerotic changes) which was associated with an increase in the serum TG, TC, LDL-C, HDL-C, MDA and aortic MDA and antioxidant reserve. Lignan complex reduced the development of atherosclerosis by 34.37% and this was associated with a decrease in serum TC by 20%, LDL-C by 14%, TC/HDL-C by 34%, serum MDA by 35% and aortic MDA by 58%. Serum HDL-C was elevated by 30% in hypercholesterolemic rabbits and by 25% in normocholesterolemic rabbits with lignan complex. Lignan complex did not affect the TC and LDL-C and serum MDA in the normocholesterolemic rabbits. However, it increased the aortic MDA in the normocholesterolemic rabbits. These results suggest that lignan complex isolated from flaxseed reduced the extent of hypercholesterolemic atherosclerosis and this effect was associated with marked decreases in oxidative stress, serum total cholesterol, LDL-C and risk ratio, and elevation of serum HDL-C. Lignan complex may, therefore, be beneficial in preventing atherosclerosis, and reducing risk factors for coronary artery disease and stroke.     

Suppression of hypercholesterolemic atherosclerosis by pentoxifylline and its mechanism

Reactive oxygen species (ROS) have been implicated in the development of hypercholesterolemic atherosclerosis. Hypercholesterolemia increases the levels of platelet activating factor (PAF) and cytokines which are known to stimulate granulocytes and endothelial cells to produce ROS. Pentoxifylline (PTX) is an inhibitor of cytokines and PAF and would reduce the generation of ROS by granulocytes and endothelial cells. PTX therefore would be expected to reduce the development of hypercholesterolemic atherosclerosis. New Zealand white female rabbits were assigned to four groups: Group I (n=12), control; Group II (n=5), PTX control (40 mg/kg body weight daily orally); Group III (n=13), 0.5% cholesterol; Group IV (n=9), 0.5% cholesterol+PTX (40 mg/kg body weight daily orally). Blood samples were collected before (0 time) and after 1 and 2 months on experimental diets for measurement of serum triglycerides (TG), total cholesterol (TC), LDL-C, HDL-C and serum malondialdehyde (MDA), a lipid peroxidation product. At the end of 2 months the aorta was removed for measurement of atherosclerotic plaques, MDA, and aortic tissue chemiluminescence (Ao-CL), a marker for antioxidant reserve. Rabbits in Group III developed atherosclerosis (56.61+/-6.90% of the intimal surface of aorta was covered with atherosclerotic plaques) which was associated with an increase in the serum TG, TC, LDL-C, HDL-C, TC/HDL-C, MDA and aortic MDA and antioxidant reserve. PTX reduced the development of atherosclerosis by 38.1% and this was associated with decreases in serum MDA by 32%, aortic MDA by 37%, and antioxidant reserve by 17.3% without changes in the serum lipids. These results suggest that ROS generated during hypercholesterolemia via cytokines and PAF may in part contribute to the development of hypercholesterolemic atherosclerosis and that suppression of production and activity of cytokines and PAF may reduce the development of hypercholesterolemic atherosclerosis.     

Oxygen free radicals as a mechanism of hypercholesterolemic atherosclerosis: Effects of probucol

We investigated the effects of high cholesterol diet in the presence and absence of probucol on the genesis of atherosclerosis, the blood lipid profile, aortic tissue lipid peroxidation product malondialdehyde (MDA), and aortic tissue chemiluminescence (CL) a marker for antioxidant reserve in rabbits. Five groups each of 10 rabbits were studied: group I, regular rabbit chow; group II, as I + cholesterol (0.5%); group III, as I + cholesterol (0.5%) and probucol (0.5 gm/kg/day); group IV, as I + cholesterol (1%), and group V, as I + cholesterol (1%) and probucol (0.5 gm/kg/day). Blood concentrations of triglyceride (TG), total cholesterol (TC), high density lipoproteincholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), very low density lipoprotein-cholesterol (VLDL-C) were measured at monthly intervals for 4 months. The aorta was removed at the end of the protocol for assessment of atherosclerotic changes (gross and microscopic), MDA concentration and CL. TC, LDL-C, LDL-C/HDL-C ratio increased in all the groups except group I, while VLDL-C increased in group II only. HDL-C decreased in groups III, IV and V but remained unchanged in groups I and II. There was a decrease in HDL-C and VLDL-C components and an increase in LDL-C components of total cholesterol in all the groups II, III, IV and V, the changes being greater in group IV than in group II. Probucol did not appreciably affect the changes in lipid profile except that it decreased HDL-C significantly. Aortic tissue MDA increased in groups II, IV and V to a similar extent. Aortic CL which was measured only in groups I, IV and V increased to similar extent in the latter two groups. Atherosclerotic changes were greater in group II than in group III but similar to that in groups IV and V. Histological changes were practically similar in groups II, III, IV and V. The increased levels of aortic MDA and CL, which were associated with development of atherosclerosis, suggest a role for oxygen free radicals in the pathogenesis of hypercholesterolemia-induced atherosclerosis. Protection afforded by probucol was associated with a decrease in aortic MDA in spite of hypercholesterolemia. Ineffectiveness of probucol in 1% cholesterolfed rabbits was associated with its inability to reduce MDA and increase antioxidant reserve. These findings further support for the hypothesis that oxygen free radicals are involved in the genesis and maintenance of hypercholesterolemic atherosclerosis.     

药桑不同提取物对2型糖尿病大鼠的治疗作用

目的 探讨药桑醇提物与水提物对2型糖尿病(T2DM)大鼠的治疗作用.方法 采用高脂高糖饮食同时腹腔注射链脲佐菌素复制T2DM大鼠模型.将动物随机分为模型组、拜糖平阳性对照、药桑醇提物组(20 mg/kg)和水提物组(20 mg/kg),并设置正常对照组.4 w后处死大鼠取血清测定血糖、果糖胺、血脂生化指标[总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)];取新鲜肝脏测定肝糖原、超氧化物歧化酶(SOD)、丙二醛(MDA).结果 与正常对照组比较,模型组血糖、果糖胺、MDA、TC、TG、LDL-C水平明显升高(P＜0.01),肝糖窄、HDL-C含量、SOD活性明显降低(P＜0.05).与模型组比较,药桑组各项指标有明显改善(P＜0.05).结论 药桑不同提取物可降低血糖、提高机体抗氧化能力,对T2DM大鼠具有一定的治疗作用.     

Study of the correlation between blood lipid levels and the severity of coronary atherosclerosis in a Chinese population sample

OBJECTIVE: To investigate the relationship between blood lipid levels with severity of coronary artery atherosclerosis in a Chinese population sample. METHODS AND RESULTS: According to coronary angiography results, 363 patients (287 men and 76 women) with coronary artery atherosclerosis were divided into four groups: the single-vessel group (I, n = 125), the double-vessel group (II, n = 113), the triple-vessel group (III, n = 107) and the multi-vessel group (IV, n = 18).The severity of coronary artery atherosclerosis was quantified with a modified Gensini score on the basis of angiographic imaging. Serum triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-high density lipoprotein cholesterol (non-HDL-C) were measured before angiography in all groups. Levels of serum TC, LDL-C and non-HDL-C of the II, III and IV group were significantly higher than those of the I group (4.78 +/- 0.82 mmol/L and 4.87 +/- 1.50 mmol/L and 4.73 +/- 0.99 mmol/L vs. 4.38 +/- 0.93 mmol/L, 2.91 +/- 0.68 mmol/L and 2.74 +/- 1.23 mmol/L and 2.64 +/- 0.84 mmol/L vs. 2.30 +/- 0.77 mmol/L, 3.58 +/- 0.75 mmol/L and 3.59 +/- 1.41 mmol/L and 3.43 +/- 0.94 mmol/L vs. 3.17 +/- 0.91 mmol/L; p < 0.05); the mean levels of TC, LDL-C and non-HDL-C associated positively with the Gensini score. CONCLUSION: Serum lipid levels correlate positively with the severity of coronary artery atherosclerosis in a Chinese population sample. Patients with higher levels of serum TC, LDL-C and non-HDL-C have more severe coronary atherosclerosis, compared with those with low levels of serum TC, LDL-C and non-HDL-C.     

女性原发性高血压患者绝经前后脂蛋白(a)及血脂水平变化的研究

目的　观察女性原发性高血压患者绝经前后脂蛋白 (a) [L p(a) ]及血脂水平的变化 ,探讨其对女性冠心病发病情况可能存在的影响。方法　女性原发性高血压患者 12 1例 ,测定 L p(a)、总胆固醇 (TC)、三酰甘油 (TG)、低密度脂蛋白胆固醇 (L DL- C)和高密度脂蛋白胆固醇 (HDL- C)。对比绝经前后 L p(a)及血脂水平的变化 ,并与女性健康体检者 (对照组 )进行对比。结果　高血压组 L p(a)、TC、TG、L DL - C均显著高于对照组 ,而 HDL - C及 HDL - C/TC则明显低于对照组 ,在所有原发性高血压患者中 ,绝经后的患者 L p(a)、TC、TG、L DL - C显著高于绝经前患者 ,而 HDL - C/ TC则前者低于后者。结论　绝经后原发性高血压患者 L p(a)、TC、L DL - C均明显高于绝经前患者 ,而HDL- C/ TC则低于绝经前患者 ,提示绝经后女性原发性高血压患者 L p(a)及血脂水平增高与内源性雌激素水平下降有关 ,是绝经后冠心病发病率明显上升的重要原因。     

Purpurogallin in the prevention of hypercholesterolemic atherosclerosis

Effects of purpurogallin (PPG), an antioxidant on high cholesterol diet-induced atherosclerosis, and changes in blood lipid profile and lipid peroxidation product malondialdehyde (MDA), aortic tissue MDA, chemiluminescence (M-CL), a marker for antioxidant reserve and antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-P_x)] were investigated in rabbits. The rabbits were divided into three groups: Group I, regular rabbit chow; Group II, same as Group I+cholesterol (1%); and Group III, same as Group II+PPG (14 mg/kg, orally, daily). Serum concentrations of triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and blood MDA were measured before and after 4 and 10 weeks on the respective diets. The aorta was removed at the end of 10 weeks for assessment of atherosclerotic changes, MDA concentration, M-CL, and antioxidant enzymes. Coronary arteries were also examined for atherosclerotic changes. Serum TC, LDL-C, and LDL-C/HDL-C ratio increased whereas HDL-C decreased in Group II and their values were similar in Groups II and III. Aortic tissue MDA, M-CL, CAT, and GSH-P_x activity increased in Group II but these values in Group III were lower than in Group II except for MDA which was greater in Group III than in Group II. Atherosclerotic changes were greater in Group II than in Group III. Histological changes were similar in Groups II and III. Atherosclerotic changes were also observed in the coronary arteries of Groups II and III, however, they were less in Group III than in Group II. Increased levels of aortic MDA and decreased levels of antioxidant reserve, which were associated with the development of atherosclerosis, suggest a role for oxygen radicals in the pathogenesis of hypercholesterolemic atherosclerosis. The protection afforded by PPG, which was associated with reversal of the antioxidant reserve to control level, in spite of hypercholesterolemia, supports the hypothesis that oxygen radicals are involved in the development of hypercholesterolemic atherosclerosis. These results suggest that PPG retard the development of hypercholesterolemic atherosclerosis because of its antioxidant activity without lowering blood cholesterol level.     

Experimental study of osthole on treatment of hyperlipidemic and alcoholic fatty liver in animals

AIM: To evaluate the effects of osthole on fatty liver, and investigate the possible mechanism. METHODS: A quail model with hyperlipidemic fatty liver and rat model with alcoholic fatty liver were set up by feeding high fat diet and alcohol, respectively. These experimental animals were then treated with osthole 5-20 mg/kg for 6 wk, respectively. Whereafter, the lipid in serum and hepatic tissue, and coefficient of hepatic weight were measured. RESULTS: After treatment with osthole the levels of serum total cholesterol (TC), triglyceride (TG), lower density lipoprotein-cholesterol (LDL-C), coefficient of hepatic weight, and the hepatic tissue contents of TC and TG were significantly decreased. The activity of superoxide dismutase (SOD) in liver was improved. In alcohol-induced fatty liver rats, the level of malondialdehyde (MDA) in liver was decreased. In high fat-induced fatty liver quails, glutathione peroxidase (GSH-PX) in liver was significantly improved. The histological evaluation of liver specimens demonstrated that the osthole dramatically decreased lipid accumulation. CONCLUSION: These results suggested that osthole had therapeutic effects on both alcohol and high fat-induced fatty liver. The mechanism might be associated with its antioxidation.     

Large scale cohort study of the relationship between serum cholesterol concentration and coronary events with low-dose simvastatin therapy in Japanese patients with hypercholesterolemia.

Hyperlipidemia is a well-established risk factor for primary coronary heart disease (CHD). Although simvastatin is known to lower serum lipid concentrations, the protective effect of such lipid-lowering therapy against primary CHD has not been established in Japanese patients with hypercholesterolemia. The Japan Lipid Intervention Trial was a 6-year, nationwide cohort study of 47,294 patients treated with open-labeled simvastatin (5-10 mg/day) and monitored by physicians under standard clinical conditions. The aim of the study was to determine the relationship between the occurrence of CHD and the serum lipid concentrations during low-dose simvastatin treatment. Simvastatin reduced serum concentrations of total cholesterol (TC), low-density lipoprotein- cholesterol (LDL-C) and triglyceride (TG), by 18.4%, 26.8% and 16.1% on average, respectively, during the treatment period. The risk of coronary events was higher when the average TC concentration was > or =240 mg/dl and the average LDL-C concentration was > or =160 mg/dl. The incidence of coronary events increased in the patients with TG concentration > or =300 mg/dl compared with patients with TG concentration <150 mg/dl. The high-density lipoprotein cholesterol (HDL-C) inversely correlated with the risk of coronary events. The J-curve association was observed between average TC or LDL-C concentrations and total mortality. Malignancy was the most prevalent cause of death. The health of patients should be monitored closely when there is a remarkable decrease in TC and LDL-C concentrations with low-dose statin. A reasonable strategy to prevent coronary events in Japanese hypercholesterolemic patients without prior CHD under low-dose statin treatment might be regulating the serum lipid concentrations to at least <240 mg/dl for TC, <160 mg/dl for LDL-C, <300 mg/dl for TG, and >40 mg/dl for HDL-C.