北五味子乙素对大鼠离体心肌缺血再灌注损伤的保护作用及分子机制

目的：观察北五味子乙素（schisandrin B,SchB）对缺血再灌注（ischemia/reperfusion,I/R）大鼠离体心脏功能、梗死面积、乳酸脱氢酶及相关蛋白表达的影响,探讨其对I/R损伤的保护作用及分子机制。方法：Wistar大鼠50 只,随机分为5 组：空白对照组（CON）、缺血再灌注组（I/R）、SchB预保护组（SchB）、PI3K抑制剂组（I/R＋SchB＋LY）、腺苷酸活化的蛋白激酶（AMP-activated protein kinase,AMPK）抑制剂组（I/R＋SchB＋CC）。采用Langendorff法建立离体大鼠心脏I/R模型,心肌缺血2 h,再灌注5、15、30、60 min。观察I/R期间室内压最大上升速率（＋dp/dtmax）、室内压最大下降速率（－dp/dtmax）、左心室舒张末压、冠脉流量和心率;测定心脏灌流液中乳酸脱氢酶（lactate dehydrogenase,LDH）含量,2,3,5-氯化三苯基四氮唑（2,3,5-triphenyltertrazoliumchloride,TTC）染色测定各组心肌梗死面积;免疫印迹检测心肌中总蛋白激酶B（protein kinase B,PKB）、磷酸化Akt（p-Akt）、总糖原合成酶激酶-3β（glycogen synthease kinase-3β,GSK-3β）、磷酸化GSK-3β（p-GSK-3β）蛋白表达。结果：SchB可显著改善I/R所致的心肌功能损伤,减少梗死面积,提高心肌中p-Akt和p-GSK-3β蛋白表达。结论：SchB对大鼠离体心脏I/R损伤具有一定保护作用,其机制可能与激活AMPK和PI3K/Akt信号通路有关。     

Protective effects of quercetin-3-rhamnoglucoside (rutin) on ischemia-reperfusion injury in rat small intestine

Quercetin-3-rhamnoglucoside (rutin) has a wide spectrum of biochemical and pharmacological activities. Orally administered compounds are absorbed in the intestine. Although absorption of rutin from the jejunum of the rat was good, binding of rutin to the intestinal wall components may limit its absorption from the small intestine. The physiological importance of an orally administered compound depends on its interaction with target tissues. Since there is limited information on the importance of rutin in vivo, we focused on the protective effect of rutin on intestinal injury. The intestinal mucosa is extremely sensitive to reactive oxygen species. We used a rat mesenteric ischemia-reperfusion (I/R) injury model as a model of oxidative injury and investigated the antioxidant activities of rutin in vivo. We found that rutin, which has combined antioxidant activity from radical-scavenging, xanthine oxidase inhibition and chain-breaking effects, exhibits a protective effect on I/R injury in the rat small intestine.     

A Biological Role of Lutein

Lutein, a non-provitamin A carotenoid, is found in dark green, leafy vegetables. Lutein, being fat soluble, follows the same intestinal absorption path as dietary fat and is affected by the same factors that influence fat absorption. Unlike β-carotene, another major carotenoid in diet and tissue, the bioavailability of lutein appears to be less influenced by food processing. Lutein has been strongly implicated as being protective against eye diseases, age-related macular degeneration, and cataracts. In the eye, lutein may act as a blue light filter to protect the underlying tissues from phototoxic damage. The mechanism by which lutein is involved in the prevention of eye diseases may also involve its role as an antioxidant. Dietary surveys indicate that average intakes of lutein in the United States may be below levels that are associated with disease prevention. Therefore, increased intakes of food sources rich in lutein may be warranted.     

叶黄素的视力保护作用及提取工艺

叶黄素(lutein)是一种含氧的类胡萝卜素,分布在黄斑区和整个视网膜,具有蓝光屏蔽和抗氧化功能,具有重要的保护视力的作用。本文介绍了叶黄素与黄斑变性、白内障的关系,揭示其对视觉发育及功能的影响,并总结了叶黄素的提取技术,通过示例探讨了提取条件优化及工艺特点,最后展望了黄素的及提取方法与市场前景。     

叶黄素对早期动脉粥样硬化的保护作用及其机制

叶黄素是类胡萝卜素之一,因其具有独特的生物活性而备受关注。它含有羟基和多个共轭不饱和双键结构,具有抗氧化作用,能够抑制LDL过氧化损伤和抑制血管内皮细胞黏附分子的过度表达,对早期动脉粥样硬化可能具有保护作用。重点介绍了叶黄素对早期动脉粥样硬化的保护作用及其机制的研究进展。     

甘草苷抗脑缺血再灌注炎性损伤研究

目的：探讨甘草苷抗小鼠脑缺血再灌注炎性损伤作用及机制。方法：将ICR 小鼠随机分为假手术组、模型组、阳性对照组(依达拉奉3mg/(kg bw·d)和甘草苷高、中、低剂量(40、20、10mg/(kg bw·d))组。采用线栓法建立局灶性脑缺血再灌注损伤模型,缺血2h 再灌注22h 后,观察脑组织病理学变化、测定髓过氧化物酶(MPO)活性,检测细胞间黏附因子-1(ICAM-1)表达。结果：与模型组相比,甘草苷可明显减轻脑组织病理学改变,降低MPO 活性及ICAM-1 表达。结论：甘草苷具有抗脑缺血再灌注炎性损伤活性。     

万寿菊叶黄素的提取及分析方法研究进展

叶黄素（lutein）是自然界广泛存在的含紫罗酮环的二羟基类胡萝卜素，也是人眼视网膜黄斑色素主要组成部分。由于叶黄素可有效预防并辅助治疗老年性黄斑退化病和白内障等眼部疾病，其在生物活性物质利用领域有广泛的应用前景。万寿菊是工业上提取分离叶黄素的理想工业原料。本文综述了近年来国内外有关万寿菊叶黄素的研究工作，着重介绍叶黄素的新型提取方法及其定性定量分析方法。     

叶黄素对铁过载大鼠氧化应激水平影响的实验研究

目的:铁是人体必需的微量元素之一,但机体内铁负荷过多可诱导氧化应激,造成细胞和组织损伤。本研究通过建立铁过载大鼠模型,探讨不同剂量叶黄素对其氧化应激水平的影响。方法:60只SD雄性大鼠随机分为5组,每组12只。正常对照组大鼠饲喂基础饲料(铁含量50 mg/kg),其他大鼠均饲喂高铁饲料(铁含量1 000 mg/kg),建立铁过载模型大鼠,同时随机分为高铁负荷组、高铁+叶黄素低剂量组(10 mg/kg·bw)、高铁+叶黄素中剂量组(20 mg/kg·bw)、高铁+叶黄素高剂量组(40 mg/kg·bw)。持续喂养6w后,测定血清铁蛋白、血清铁、肝组织铁及血清和肝匀浆中总超氧化物歧化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)、丙二醛(MDA)等含量。结果:与正常对照组比较,高铁负荷组大鼠血清铁及血清铁蛋白含量均升高28%(P值均0.05),肝组织铁含量升高23%(P0.01)。与高铁负荷组大鼠比较,添加叶黄素低剂量、中剂量和高剂量的高铁负荷组大鼠血清铁、血清铁蛋白及肝组织铁含量均显著降低(P值均0.05),与正常对照组水平无显著差异(P值均0.05)。氧化应激水平分析显示,高铁负荷组大鼠血清GSH-Px活力和肝匀浆GSH-Px活力比正常对照组分别降低了12%和20%(P值均0.05)。中剂量叶黄素组大鼠血清GSH-Px及CAT活力比高铁负荷组分别提高了12%、32%(P值均0.05);高剂量叶黄素组肝匀浆GSH-Px活力比高铁负荷组大鼠提高了23%(P0.05)。与正常对照组比较,高铁负荷和高铁+低剂量叶黄素组肝匀浆T-SOD活力分别降低了20%和17%(P值均0.05)。而高剂量叶黄素组大鼠肝匀浆T-SOD活力与高铁负荷和高铁+低剂量叶黄素组大鼠相比分别提高了22%和19%(P值均0.05)。高铁负荷组大鼠肝匀浆CAT活力比正常组降低了19%(P0.05),比中剂量叶黄素组下降了22%(P0.05)。结论:铁负荷过载可降低机体多种抗氧化酶的活性,增加机体氧化应激水平;补充叶黄素可有效地减少高铁负荷损伤,提高抗氧化能力,较高剂量补充的效果可能更明显。     

Caffeic Acid Phenethyl Ester: A Review of Its Antioxidant Activity,Protective Effects against Ischemia-reperfusion Injury and Drug Adverse Reactions

Propolis, a honey bee product, has been used in folk medicine for centuries for the treatment of abscesses, canker sores and for wound healing. Caffeic acid phenethyl ester (CAPE) is one of the most extensively investigated active components of propolis which possess many biological activities, including antibacterial, antiviral, antioxidant, anti-inflammatory, and anti-cancer effects. CAPE is a polyphenolic compound characterized by potent antioxidant and cytoprotective activities and protective effects against ischemia–reperfusion (I/R)-induced injury in multiple tissues such as brain, retina, heart, skeletal muscles, testis, ovaries, intestine, colon, and liver. Furthermore, several studies indicated the protective effects of CAPE against chemotherapy-induced adverse drug reactions (ADRs) including several antibiotics (streptomycin, vancomycin, isoniazid, ethambutol) and chemotherapeutic agents (mitomycin, doxorubicin, cisplatin, methotrexate). Due to the broad spectrum of pharmacological activities of CAPE, this review makes a special focus on the recently published data about CAPE antioxidant activity as well as its protective effects against I/R-induced injury and many adverse drug reactions.     

Dietary fatty acid determines the intestinal absorption of lutein in lutein deficient mice

The present investigation was undertaken to study the influence of dietary lipids [olive (OO), coconut (CNO), groundnut (GNO), soybean (SBO), sunflower (SFO), rice bran (RBO), corn (CO), palm (PO), fish (FO) oils] on the bioavailability and antioxidant property of lutein in lutein deficient (LD) mice. Lutein (200 μM) was dispersed in dietary lipids and administered to LD mice for a period of 15 days. The plasma lutein levels were found to be highest in OO (82%) and CNO (68%), when compared to the control (mixed micelle) group. Further, positive correlation was found between intestinal triacylglycerol lipase and plasma lutein levels, confirming the crucial role of intestinal lipase on lutein micellarization and its intestinal uptake. Results revealed an affirmative correlation between triglycerides, low density lipoproteins and high density lipoprotein levels with plasma and tissue lutein levels, signifying their role in the transportation of newly absorbed lutein to target tissues. Furthermore, lutein accumulation in the liver and the eye was highest in the OO (120% and 117%) and CNO (105% and 109%) fed groups, compared to control. Lutein deficiency resulted in elevated (p < 0.05) levels of lipid peroxides, superoxide dismutase, and catalase in plasma and liver microsomes, which have been decreased significantly on feeding lutein. These results may be due to the influence of oleic (dominant in OO) and lauric (dominant in CNO) acids on the activity of intestinal lipase, portal absorption, triglycerides, lipoprotein or cholesterol flux between liver and peripheral tissues, which may modulate the uptake and transport of lutein.     

Atrial natriuretic peptide enhances recovery from ischemia/reperfusion-induced renal injury in rats

Recovery from ischemic acute kidney injury requires the replacement of damaged tubular cells. This repair process involves epidermal growth factor (EGF) synthesized in medullary the thick ascending limbs (mTAL) of Henle. Atrial natriuretic peptide (ANP), a hormone synthesized by the cardiac atria, increases glomerular filtration rate and renal medullary blood flow. However, the effects of ANP on renal recovery after I/R-induced renal injury remain unclear. We therefore examined whether human ANP enhances recovery from I/R-induced renal injury by reducing damage to EGF-producing kidney cells in a rat model. Male Wistar rats weighing 200–240 g were observed for 48 h after reperfusion following 45-min renal ischemia. Rats were intravenously administered α-human ANP (α-hANP) at 0.2 μg/kg/min beginning immediately after ischemia and continuing for 2 h after reperfusion. Outer medullary blood flow (OMBF), EGF mRNA, serum blood urea nitrogen (BUN) and creatinine levels as indicators of glomerular function were measured, while urinary N-acetyl β-d-glucosaminidase (NAG) was used as a specific indicator of proximal tubular function. OMBF was increased by α-hANP after reperfusion and maintained significantly higher mRNA level of EGF in the kidney 24 h after reperfusion. I/R-induced increases in serum concentrations of BUN and creatinine and urinary concentrations of NAG were also reduced by α-hANP, with improved histopathological changes, including acute tubular necrosis at 24–48 h after reperfusion. This report is the first to demonstrate that α-hANP accelerates recovery following renal ischemic insult by reducing the damage to EGF-producing kidney cells.     

Protective role of air potato (Dioscorea bulbifera) of yam family in myocardial ischemic reperfusion injury

Hydroalcoholic extract of Dioscorea bulbifera (DB), a yam variety called air potato, was tested for its protective effect on myocardial ischemic/reperfusion (I/R) injury in rats due to apoptosis and necrosis. Myocardial I/R injury was induced by 30 min ischemia followed by 2 h reperfusion by perfusing isolated rat hearts with Krebs Henseilet bicarbonate (KHB) buffer in a Langendorff set up. Pretreatment of DB (150 mg kg(-1) body weight) for 30 days significantly reduced myocardial infarct size and improved the ventricular function (aortic flow and coronary flow, LVDP, LVmax dp/dt). Role of DB on apoptosis was also evaluated by determining caspase 3 as well as by examining pro-apoptotic and anti-apoptotic proteins Bax and Bcl2 by Western blot analysis followed by TUNEL assay. DB also prevented I/R-mediated down regulation of survival protein Akt and HO-1. Our results indicated that Dioscorea bulbifera could ameliorate myocardial ischemia and reperfusion injury by improving ventricular function and inhibition of cardiomyocyte necrosis and apoptosis.     

血管紧张素转移酶2(ACE2)在糖尿病致大鼠肝脏氧化应激损伤中的作用及机制分析

目的：探讨血管紧张素转移酶2(ACE2)在糖尿病致大鼠肝脏氧化应激损伤中的作用和可能机制。方法：24只健康雄性SD大鼠,随机选取8只作为正常对照组,剩余16只按60mg/kg(以体质量计)一次性腹腔注射STZ溶液制备糖尿病肝脏氧化应激损伤模型,成模后大鼠随机分为2组：糖尿病组和胰岛素治疗组(优泌林 3.7×10-8mol/d),30d后宰杀,取血液和肝脏组织等进行各指标测定：1)测定血清中AGEs含量;2)测定肝脏组织中过氧化氢(H2O2)、丙二醛(MDA)的含量及过氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活力;3) 肝脏组织中血管紧张素Ⅱ(AngⅡ)、血管紧张素1-7(Ang1-7)的含量,ACE和ACE2酶活力的测定。结果：1)正常对照组大鼠空腹血糖均值为(5.39±0.30)mmol/L,糖尿病组大鼠空腹血糖均值持续维持在(28.24±2.51)mmol/L(远高于高水平高血糖状态指标值16.6mmol/L),胰岛素治疗后大鼠空腹血糖水平明显下降至(11.18±1.26)mmol/L,显著高于正常对照组(P＜0.05),但同时显著低于糖尿病组(P＜0.05),且治疗后期已经低于10.0mmol/L并逐渐接近正常对照组。糖尿病组大鼠血清中的AGEs的含量显著高于正常对照组和胰岛素治疗组(P＜0.05)。2) 与正常对照组和胰岛素治疗组相比,糖尿病组大鼠肝脏组织中的MDA和H2O2极显著增多(P＜0.01),SOD和GSH-Px的活力极显著降低(P＜0.01); AngⅡ的含量显著增多(P＜0.01),Ang1-7含量显著降低(P＜0.01),ACE的酶活力显著升高(P＜0.01),而ACE2的酶活力显著降低(P＜0.01)。 结论： 糖尿病时大鼠肝脏组织局部AngⅡ显著升高,ACE2活力下降,肝脏组织处于氧化应激状态。胰岛素治疗后,ACE2活力增高,致AngⅡ降解,AngⅡ含量显著降低,肝脏的氧化应激减缓,提示ACE2对糖尿病大鼠肝脏氧化应激损伤有一定的保护作用,其机理可能与对AngⅡ降解作用增强有关。     

高效液相色谱法测定蛋白核小球藻中的叶黄素

采用反相高效液相色谱法(RP-HPLC)分离测定了蛋白核小球藻中的叶黄素。样品制备采用甲醇-二氯甲烷(体积比为2：1)混合溶剂为叶黄素提取剂，所用色谱柱为Nova-Pak~(?)C_(18)不锈钢柱，以甲醇-乙腈-水(体积比为80：10：10)和甲醇-乙腈(体积比为40：60)为流动相，线性梯度洗脱，流速0.8mL／min，在447nm下用光电二极管阵列检测器(DAD)检测。测定结果显示，在0～60mg／L范围内，标准曲线呈良好的线性关系(r=0.9999)，叶黄素的保留时间为11.25min，浓度的相对标准偏差为0.49％(n=6)，平均加样回收率为99.7％。该法简单、快速、准确。     

A Simple and Selective Analytical Procedure for the Extraction and Quantification of Lutein from Tomato By-Products by HPLC–DAD

Lutein, a yellow dihydroxylated carotenoid, is present in many dietary supplements due to its biological properties. Currently, lutein is extracted from marigold flowers by expensive and time-consuming processes. Since tomatoes contain significant levels of lutein, in this study we have examined the feasibility of using tomato by-products as an alternative, low-cost source of this carotenoid. The determination of this carotenoid was performed by high-performance liquid chromatography–diode array detection, after selective extraction from tomato waste product samples. Lutein levels ranged from 9.9 to 10.5 μg/g dry weight. Tomato waste products may be indicated as an alternative commercial source of lutein for food fortification and/or dietary supplements.     

Content of lutein in aqueous extracts of yerba mate (Ilex paraguariensis St. Hil)

Lutein is the main carotenoid in green leafy vegetables. It has been associated to reduction of risks of progression of macular degeneration, therefore, the consumption of lutein through diet is essential to help prevention of blindness and cataract. In this study, we investigated lutein in aqueous extracts of yerba mate by ultra high performance liquid chromatoraphy and mass spectrometry. Different commercial types of yerba mate for chimarrão (smooth, traditional and coarse-ground) and terere were analyzed. The effect of temperature on the amount of lutein extracted was also investigated. We observed that terere extracts presented lutein content higher (17 μg) than chimarrão extracts, and among chimarrão commercial types, coarse-ground presented the highest lutein content (in average 9.5 μg). We also verified that water temperature incremental favored the lutein migration to aqueous extract. The levels of lutein found in the yerba mate infusions investigated in this study were superior to others tea drinks, showing that aqueous extracts of yerba mate can contribute significantly to the ingestion of lutein.     

万寿菊花中叶黄素酯的提取及皂化工艺

叶黄素具有调节人体的免疫能力、防治老年性视黄斑退化和白内障等作用,目前天然叶黄素的提取原料主要为万寿菊花,万寿菊花的有机溶剂提取物含有大量叶黄素酯,经皂化后可转变为叶黄素,广泛用于食品、食品添加剂、药品及饲料等工业.本文采用甲醇处理万寿菊鲜花后直接用正己烷提取叶黄素酯,并通过L9 (34)正交实验选择了叶黄素酯皂化的最佳条件,即KOH/甲醇浓度为20%,提取液﹕KOH为4 : 1,时间为40min,温度为50℃时,叶黄素酯皂化进行的比较完全.皂化得到的叶黄素在丙酮﹕甲醇(v : v)为1 : 1的混合溶剂中进行重结晶,得到叶黄素晶体,纯度为97.2%.     

Effects of lutein and zeaxanthin on aspects of eye health

Lutein and zeaxanthin are members of the oxygenated carotenoids found particularly in egg yolks and dark‐green leafy vegetables. A great deal of research has focused on their beneficial roles in eye health. The present article summarises the current literature related to the bioactivity of these carotenoids, emphasising their effects and possible mechanisms of action in relation to human eye health. Available evidence demonstrates that lutein and zeaxanthin are widely distributed in a number of body tissues and are uniquely concentrated in the retina and lens, indicating that each has a possible specific function in these two vital ocular tissues. Most of epidemiological studies and clinical trials support the notion that lutein and zeaxanthin have a potential role in the prevention and treatment of certain eye diseases such as age‐related macular degeneration, cataract and retinitis pigmentosa. The biological mechanisms for the protective effects of these carotenoids may include powerful blue‐light filtering activities and antioxidant properties. Although most studies point towards significant health benefits from lutein and zeaxanthin, further large‐scale randomised supplementation trials are needed to define their effects on ocular function in health and disease. Copyright © 2009 Society of Chemical Industry     

高效液相色谱-电喷雾质谱法测定浒苔中的叶黄素

建立反相高效液相色谱- 电喷雾电离质谱法(RP-HPLC-DAD-ESI-MS)定性、定量测定绿潮藻浒苔中叶黄素的新方法。浒苔样品经超声辅助提取后,采用RP-HPLC-DAD-ESI-MS 联用技术对其进行分离鉴定,HPLC 采用Eclipse XDB-C18(150mm × 4.6mm,5μm)色谱柱,以含0.2% 乙酸的甲醇溶液- 水为流动相,线性梯度洗脱,检测波长450nm。在选定的最佳仪器条件下,叶黄素与浒苔中的其他化合物分离良好,叶黄素在0.10～20.0mg/L 质量浓度范围内具有良好的线性关系(R2=0.9994),能对浒苔提取液中的叶黄素进行准确定量;采用电喷雾质谱联用分析能快速获得叶黄素的分子量信息,可为浒苔中叶黄素的快速鉴别提供依据。     

Lutein: a valuable ingredient of fruit and vegetables

Lutein is a human serum carotenoid which is not synthesized by humans and thus must be obtained by the ingestion of food containing it such as fruits and vegetables. Lutein is present in different forms in those foods as all-trans-lutein, cis-lutein, epoxi-lutein, and lutein linked to proteins. It discusses if the intake of lutein or diets supplemented with lutein or diets rich in fruits and vegetables are important in the prevention of diseases like some cancers, cardiovascular diseases, etc., that may be affected by the antioxidant effect of lutein; or in the prevention of age-related macular degeneration and other eye diseases. The concentration of lutein in fruits and vegetables depends on the species. We've included the concentration of lutein in 74 species reported by different authors since 1990. Currently the quantification of lutein is mainly performed by HPLC, but more investigations into a quantification method for lutein, lutein isomers, and epoxi-lutein are necessary. Improvement of lutein extraction methods is important as well. Methods commonly used in the vegetable and fruit industry like heat treatment, storage conditions, etc. can change lutein concentrations; other factors depend on the plant, for instance the variety, the stage of maturity, etc.