Effect of dried, powdered Chlorella vulgaris on experimental atherosclerosis and alimentary hypercholesterolemia in cholesterol-fed rabbits

The anti-lipidemic action and anti-atherosclerotic action of dried, powdered Chlorella vulgaris (CVP) were investigated using male Japanese White rabbits. A ten-week load of high-cholesterol diet remarkably increased serum total cholesterol and the beta-lipoprotein cholesterol levels in serum, causing aortic atheromatous lesion. In the Chlorella group which was administered a high-cholesterol diet containing 1% powdered Chlorella vulgaris, increase of total and beta-lipoprotein cholesterol level was suppressed. Further, the development of aortic atheromatous lesions was significantly inhibited. Clofibrate used as positive control in this experiment, did not show any inhibitory effect, either on the increase in serum lipid level or on the development of aortic atheromatous lesion.     

Effect of blackgram fibre on ethanol-induced hyperlipidemia in rats

Rats fed a diet low in fibre and provided with ethanol for 4 weeks showed a higher concentration of cholesterol in the serum, liver and heart, but not in the aorta when compared with control rats not provided with ethanol. Animals maintained on a diet of blackgram fibre (30%) and provided with ethanol had significantly lower concentration of cholesterol in these tissues and in the aorta. The concentration of triglyceride was also raised in the serum, liver and heart in rats fed a diet low in fibre + ethanol. A diet of blackgram fibre caused a significant decrease in serum and liver triglyceride. Fecal excretion of neutral sterols and bile acids decreased in rats fed a diet low in fibre + ethanol, whereas blackgram fibre caused an increase in such fecal excretion.     

U50,488H对高脂大鼠血管内皮功能的影响

目的 探讨κ-阿片受体（κ-OR）选择性激动剂U50,488H对高脂大鼠血管内皮功能的影响及其机制。方法 成年SD大鼠分别饲以正常和高脂饲料14周,腹腔隔日注射U50,488H和κ-OR阻断剂nor-BNI,麻醉后下腔静脉取血,检测总胆固醇（TC）及低密度脂蛋白（LDL）的水平。透射电子显微镜观察动脉内皮细胞和平滑肌细胞的超微结构改变。观察胸主动脉对内皮依赖性血管舒张剂乙酰胆碱（ACh）及内皮非依赖性血管舒张剂（SNAP）的舒张反应。结果 高脂饲料喂养可引起大鼠血清TC和LDL显著升高;主动脉血管内皮依赖性舒张功能显著降低。透射电镜下可见动脉内皮细胞和平滑肌细胞的超微结构出现损伤。U50,488H可显著减轻高脂血症引起的血管内皮依赖性舒张功能障碍和动脉内皮细胞与平滑肌细胞超微结构损伤,κ-OR阻断剂nor-BNI可以阻断U50,488H的上述作用。结论 高脂血症大鼠存在内皮功能障碍,U50,488H可通过激活κ-OR改善高脂血症导致的内皮结构改变和功能障碍。     

The protection of Thymus vulgaris leaves alcoholic extract against hepatotoxicity of alcohol in rats

Objective:This study was performed to investigate the protective effect of Thymus vulgaris(T.vulgaris) leaves 70%alcoholic extract against alcohol-mediate hepatotoxicity rats.Methods:The protective effect of extract was investigated at dose of 500 mg/kg/day orally against alcohol-mediate hepatotoxicity using adult male Wister albino rats during 21 days.Protective effect of T.vulgaris extract was evaluated comparing with silymarin standard drug al recommended dose(25 mg/kg/day) orally for 21 days.Results:Alcohol-mediate hepatotoxicity rats(alcohol-control) showed hepatocytes distortion represented as marked increment on liver biomarkers;alkaline phosphatase(ALP),aspartate transaminase(AST) and alanine transaminase(ALT) activities,as well as pronounced reduction on total protein and its fractions albumin and globulin corresponding to normal ranges.Addition to oxidative stress status as depletion on glutathione concentration,catalase(CAT),superoxide dismutase(SOD),glutathione reductase(GR),glutathione-S-transferase(GST) and glutathione peroxidase(GPx)activities,concurrence with augmentation oxidative stress parameters;malondyaldchydc(MDA) and hydrogen peroxide(H_2O_2) concentrations comparing to normal values.Alcohol administration elevated total cholesterol(TC),low density lipoprotein cholesterol(LDL-C) and high density lipoprotein cholesterol(HDL-C) comparing to normal ranges.Co-administration T.vulgaris extract with alcohol showed protective effect on hepatocytes manifested as minimizing on ALP.AST and ALT activities and increment on total protein,albumin and globulin production compared to alcohol-control.Antioxidant enzymes activities;CAT.SOD.GR,GST and GPx were significantly magnified,while MDA and H_2O_2 concentration were lessened corresponding to alcohol-control.Also,lipid profile was markedly improved and risk ratio was lowered compared to alcohol-control.These results were confirmed by normalization of degenerated and fibrotic liver tissue as of alcohol-control.Conclusion:T.vulgaris extract appeared hepatoprotective,hypolipidemic and antioxidant activities on alcohol-mediate hepatotoxicity rats compared to silymarin.     

Effect of ginkgo biloba extract on livers in aged rats

AIM: To investigate the protective effect of ginkgo biloba extract (GBE) on livers of aged rats and the associated mechanisms. METHODS: Two-mo- and 20-mo-old rats were treated with GBE/saline for 3 mo. Liver tissue samples from 5-mo-old rats treated with saline (group Y) and 23-mo-old rats treated with GBE (group E) or saline (group N) were used for histopathological examinations (hematoxylin-eosin and Masson staining, Lipofuscin staining-Schmorl staining) and determination of expression of tissue inhibitor-1 of metalloproteinase (TIMP-1) and the level of malondialdehyde (MDA), glutathione peroxidase (GPx) and superoxide dismutase (SOD). Blood samples were collected for determination of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL) and albumin. RESULTS: Microscopic studies with Masson staining revealed mild liver fibrosis in aged rats (group N), while the livers of aged rats receiving GBE (group E) showed amelioration in fibrosis (2.2±0.1 vs2.8±0.1, P＜0.01) and deposition of lipofuscin (33.7±5.3 vs62.8±5.7, P＜0.01). The expression of TIMP-1 and the level of liver MDA (1.0±0.1 vs1.2±0.2,P＜0.05) also decreased but the activity of GPx (97.1±15.3 vs61.8±14.5, P＜0.01) increased in group E. Compared with group Y, the level of liver MDA (0.8±0.1 vs1.2±0.2, P＜0.01), lipofuscin (32.4±6.0 vs 62.8±5.7, P＜0.01) and TIMP-1 expression were increased, while the activity of GPx (103.2±17.6 vs61.8±14.5, P＜0.01) and SOD (16.7±4.4 vs11.8±3.9, P＜0.05) was decreased in group N. There was no difference in liver function among these three groups. CONCLUSION: GBE has protective effects on aging liver. The possible mechanisms might be its antioxidant activity and inhibition of TIMP-1 expression.     

Effect of exogenous hyperinsulinaemia on atherogenesis in cholesterol-fed rabbits

Summary To examine the hypothesis that hyperinsulinaemia promotes atherosclerosis, cholesterol-fed rabbits were injected subcutaneously with 6 IU of human insulin (n = 16) or placebo (n = 20) daily for 24 weeks; injection of insulin resulted in hyperinsulinaemia for up to 16 h after injection. Compared to placebo rabbits, insulin-treated rabbits had higher levels of insulin antibodies in plasma, similar levels of intermediate density, low density and high density lipoprotein cholesterol and similar activities of hepatic and lipoprotein lipase in post-heparin plasma, but lower levels of plasma C-peptide, blood glucose, postprandial plasma triglycerides, plasma cholesterol and very low density lipoprotein cholesterol. On univariate analysis, with and without adjustment for differences in plasma cholesterol levels between the two groups, there were no significant differences in extent or severity of atherosclerosis between insulin and placebo rabbits. Furthermore, after combining the results from all the rabbits to examine plasma insulin levels and the other variables mentioned above as predictors of atherosclerosis severity, plasma insulin level was not a predictor, on univariate or multiple linear regression analysis; the first ranked independent predictors were postprandial intermediate density lipoprotein cholesterol in the arch, and postprandial plasma triglyceride in both the thoracic and abdominal aorta. These results suggest that exogenous hyperinsulinaemia does not promote atherogenesis in cholesterol-fed rabbits, but that postprandial levels of intermediate density lipoprotein cholesterol or plasma triglycerides may be involved in atherogenesis. [Diabetologia (1997) 40: 512–520] Received: 10 October 1996 and in revised form: 28 January 1997     

实验性高脂血症及慢性间歇低氧大鼠主动脉超微结构的改变

目的观察实验性高脂血症及慢性间歇低氧对大鼠动脉超微结构的影响,探讨这种影响可能的机制。方法72只雄性Wistar大鼠随机均分为3组,对照组：普通鼠料喂养；高脂组：高脂饲料喂养；高脂＋间歇低氧组：高脂饲料喂养,同时给予7 h/d间歇低氧处理。观察3组大鼠第3、6、9周末胸主动脉结构的改变。结果对照组大鼠主动脉结构未见异常；高脂组主动脉内膜、中膜具有多种超微病理改变；高脂＋间歇低氧组损伤更为明显,逐渐出现内皮细胞变形、坏死、脱落,平滑肌细胞迁移、增殖、凋亡,胶原纤维大量增生,内弹力板断裂,胶原纤维暴露于管腔表面,至9周末高脂＋间歇低氧组已明显可见管腔表面血小板聚集。结论高脂加慢性间歇低氧复合条件对动脉超微结构损伤较单纯高脂更为明显,且随时间推移损伤逐渐加重。     

量子降脂仪对高脂血症大鼠血脂的影响及其机制

目的观察量子降脂仪对高脂血症模型大鼠的降血脂作用并探讨其机制。方法以高脂饲料和10%果糖自由饮水建立无特定病原体动物(SPF)级大鼠高脂血症模型。量子降脂仪输出功率强度为70μW/(cm2·min),每天治疗1～2次,治疗时间为每次5～10 min。采用Elisa试剂盒检测血清中血脂水平,Western blot方法检测脂类代谢和炎症通路关键蛋白表达水平的变化。结果量子降脂仪明显改善由高脂血症引起的的血脂代谢紊乱、调节血脂平衡、降低炎症状态、缓解肝功能损伤、缓解氧化损伤、提高脂肪代谢相关酶的活性、抑制脂肪酸合成酶的活性。Western blot结果显示,量子降脂仪通过调节核因子κB(NF-κB)、肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)蛋白的表达水平,缓解机体慢性炎症;通过调节过氧化体增殖物激活型受体α(PPARα)蛋白的表达水平促进机体脂质代谢;通过调节胆固醇调节元件结合蛋白2(SREBP-2)通路,促进低密度脂蛋白受体(LDLR)蛋白表达,缓解脂质代谢紊乱,调节机体高胆固醇和高甘油三酯水平。结论量子降脂仪具有明显降血脂作用,可作为降血脂医疗器械辅助应用于临床。     

桑葚提取物对实验性高脂血症预防作用的研究

目的：利用实验性高脂血症动物模型,观察桑葚提取物对兔血脂的影响。方法：36只新西兰兔分为6组。空白组给予基础饲料喂养,模型组给予高脂饮食;桑葚组将桑葚提取液与高脂饲料混合喂养新西兰兔,该组又分为低剂量组（1g／kg）、中剂量组（5g／kg）、高剂量组（10g／kg）。于用药0,2,4,6,8周末测定各组血清脂质含量。结果：桑葚三组与模型组比较均可显著降低血清总胆固醇、甘油三酯的水平（P均〈0．01）;中、高剂量组还降低血清低密度脂蛋白和载脂蛋白B的水平（P〈0．05,〈0．01）。桑葚中、高剂量组可显著提高血清高密度脂蛋白及载脂蛋白A1的水平（P〈0．05-〈0．01）。结论：桑葚提取液对兔实验性高脂血症有一定的预防作用,且随着剂量的增加而作用加强。     

白萝卜提取物对大鼠小肠动力作用的影响

[目的]研究白萝卜提取物(Raphanus sativus L extract,Ecr)和西沙比利对大鼠小肠动力作用的影响,并进行对比观察,为开发Ecr促胃肠动力作用的药用价值提供理论依据。[方法]采用旋转蒸发的方法制备Ecr后,以1 ml/kg(每1 ml折合生药约57 g)的剂量灌胃给药,同时设立西沙比利对照组和0.85%氯化钠对照组。应用小肠肌电测定和胃肠内标记物葡聚糖蓝2000进行标记的方法,测定给药前后大鼠小肠消化间期移行性复合肌电活动(Interdigestive myoelectrical complex,IMC)的变化和小肠推进比。[结果]Ecr对小肠推进有明显促进作用,IMC周期显著缩短,活动期单位时间内快波数明显增加,且与西沙比利组没有显著性差异,但与0.85%氯化钠对照组相比差异有统计学意义。[结论]Ecr对大鼠小肠动力具有显著的促进作用,其作用效果与西沙比利相近。     

虎杖降脂颗粒对高脂血症大鼠降脂作用的研究

目的研究虎杖降脂颗粒对饮食性大鼠高脂血症的治疗作用。方法采用高脂性饮食诱导大鼠高脂血症,给予口服不同剂量的虎杖降脂颗粒,观察药物对模型动物血脂水平、体质量变化和肝脏脏器指数,肝脏脂质TC、TG,血清AST、ALT、肌酐和尿素氮以及肝脏组织形态的影响。结果虎杖降脂颗粒各剂量组大鼠肝指数及肝组织脂质TC和TG均明显下降(P0.05或P0.01);血清中TC、LDL-C、HDL-C含量不同程度地降低(P0.05或P0.01),但对TG作用不明显;血清AST、ALT有不同程度的降低(P0.05或P0.01),但对血清肌酐和尿素氮无明显作用。肝组织病理学结果表明,虎杖降脂颗粒各剂量组能不同程度地降低模型大鼠的肝脏脂肪变性程度。结论虎杖降脂颗粒可有效调节高脂乳剂所致高脂血症大鼠血脂和肝脂水平,对高脂血症具有较好的调脂作用。     

辛伐他汀对高脂血症大鼠心肌细胞内质网应激相关凋亡的影响

目的 探讨辛伐他汀对高脂血症大鼠内质网应激(ERS)相关心肌细胞凋亡的影响及其机制.方法 清洁级雄性Wistar大鼠24只,随机分为正常对照组(n=8,普通饲料饲养),高脂血症组(n=8,高脂饲料饲养),辛伐他汀组(n=8,高脂饲料+辛伐他汀10 mg·kg-1·d-1灌胃饲养).12 w后,全自动化生化仪检测血清甘油三酯(TG)及胆固醇(TC)水平;HE染色观察心肌组织的病理学变化;TUNEL法检测心肌细胞凋亡;免疫组化法及RT-PCR技术检测心肌细胞ERS信号通路分子--葡萄糖调节蛋白(GRP)78的表达.结果 与正常对照组相比,高脂血症组血清TG和TC水平、心肌细胞凋亡程度和GRP78表达水平均显著升高(P＜0.01或P＜0.05),且心肌组织结构异常;与高脂血症组比较,辛伐他汀组血清TG和TC水平、心肌细胞凋亡和GRP78表达水平均显著降低但仍高于正常对照组(P＜0.05)且心肌组织结构异常得到明显改善.结论 高脂血症可以通过激活ERS途径诱导心肌细胞凋亡并导致心肌组织结构异常,辛伐他汀可能通过干预ERS途径抑制高脂血症诱导的心肌细胞凋亡并逆转其心肌组织的结构异常,从而发挥心脏保护作用.     

莱菔提取物对大鼠结肠运动影响的研究

目的莱菔提取物(crude extract of raphanus,Ecr)对结肠运动的影响的探讨将为临床治疗结肠动力障碍提供理论依据。方法采用免疫荧光化学和电生理学方法,通过观察莱菔提取物对结肠黏膜上Cajal间质细胞(Interstitial cells of Cajal,ICCs)的超极化激活性环核苷酸门控性阳离子非选择性通道的亚型1(The tape 1 of hyperpolarization-activated cyclic nucleotide-gated cation nons-elective channel,HCN1)通道的激活,以及采用结肠离体肌条,在给予Ecr及HCN1特异性阻断剂情况下,观察结肠离体肌条收缩情况。结果给予一定剂量的Ecr情况下,结肠黏膜ICCs上的HCN1通道呈现显著激活状态,离体肌条的收缩显著增加,而在给予HCN1通道的特异性阻断剂ZD7288干预下,再给予相同剂量Ecr,结肠离体肌条收缩力显著降低。结论 Ecr促进结肠收缩,与其激活结肠黏膜ICCs上的HCN1通道密切相关,HCN1通道参与Ecr对结肠运动的调节作用。     

Effect of ethanolic extract of Embelia ribes on dyslipidemia in diabetic rats

Diabetes mellitus has been treated orally with herbal remedies based on folk medicine since ancient times. Embelia ribes burm (Myrsinaceae), known commonly as vidanga, was used in Ayurveda for its anthelmintic activity. Ayurveda describes vidanga as pungent, causes increase in digestive fire, and cures flatulence and colic. A single study reported the antihyperglycemic activity of decoction of E. ribes in glucose-induced hyperglycemic albino rabbits. In the present study, the lipid-lowering and antioxidant potential of ethanolic extract of E. ribes burm was investigated in streptozotocin (40 mg/kg, IV, single injection)-induced diabetes in rats. Twenty days of orally feeding the extract (200 mg/kg) to diabetic rats resulted in significant (P < 0.01) decrease in blood glucose, serum total cholesterol, and triglycerides, and increase in HDL-cholesterol levels when compared to pathogenic diabetic rats. Further, the extract also lowered the liver and pancreas thiobarbituric acid-reactive substances (TBARSs) values (P < 0.01) when compared to TBARS values of liver and pancreas of pathogenic diabetic rats. The results of test drug were comparable to gliclazide (25 mg/kg, orally), a standard antihyperglycemic agent. This is the first pilot study to provide biochemical evidence of potential of E. ribes in diabetic dyslipidemia.