Bioactivity studies on beta-sitosterol and its glucoside

Beta-sitosterol and beta-sitosteryl-beta-D-glucoside were isolated as analgesic constituents from the leaves of Mentha cordifolia Opiz. The acetic acid-induced writhing test showed that beta-sitosterol and beta-sitosteryl-beta-D-glucoside decreased the number of squirms induced by acetic acid by 70.0% and 73.0%, respectively, at a dose of 100 mg / kg mouse. Statistical analysis using the Kruskall Wallis one-way analysis of variance by ranks showed that these isolates approximate the analgesic activity of mefenamic acid at a 0.001 level of significance. The hot plate method confirmed their analgesic activities, as beta-sitosterol and beta-sitosteryl-beta-D-glucoside exhibited a 300% and 157% increase in pain tolerance, respectively, while mefenamic acid, a known analgesic, showed a 171% increase. Neither isolate exhibited antiinflammatory activity using the carrageenan-induced mouse paw oedema assay. Beta-sitosterol also exhibited anthelminthic and antimutagenic activities. In vitro tests using live Ascaris suum as test animals showed that the behaviour of worms treated with beta-sitosterol approximated that of the positive controls, Combantrin and Antiox. An in vivo micronucleus test showed that beta-sitosterol inhibited the mutagenicity of tetracycline by 65.3% at a dose of 0.5 mg /kg mouse. At the same dose, it did not exhibit chromosome-breaking activity.     

胆木茎中一个新的吲哚生物碱苷

目的研究中药胆木水溶性部位的化学成分。方法采用大孔吸附树脂，硅胶柱色谱和Sephadex LH20凝胶柱色谱分离纯化，通过光谱分析鉴定化合物的结构。结果从胆木水溶性部位中分离得到7个化合物，分别鉴定为： naucleamide A-10-O-β-D-glucopyranoside (I)， 5-β-carboxystrictosidin (II)， 獐牙菜苷(III)， 番木鳖苷A(IV)， 3,4-dimethoxyphenyl-β-D-glucopyranoside (V)， 3,4,5-trimethoxyphenyl-β-D-glucopyranoside (VI)， 2-phenethylrutinoside (VII)。结论化合物I为新的吲哚类生物碱苷，化合物I～VII均为首次从该植物中分得。     

虎杖晶4号对人血PMNs呼吸暴发和氧自由基的作用

应用化学发光法测定①人血PMNs受PMA刺激产生的化学发光;②黄嘌呤—黄嘌呤氧化酶体系产生O_2;③VitC—CU~(2+)—酵母多糖产主·OH;④H_2O_2的释放。观察虎杖晶4号对上述体系产生自由基的影响。结果提示.虎杖晶4号对PMN呼吸暴发的早期(1～6 min)有明显的抑制作用,呈剂量依赖性;而在12min时发光强度均高于空白对照.表明因虎杖晶4号而使呼吸暴发滞后。其对O_2.·OH.H_2O_2均有清除作用.且呈剂量依赖性.IC_(50)分别为14.6.29.6和13.0μmol·L~(-1).     

旱莲草化学成分旱莲甙A和旱莲甙B的分离和鉴定

自旱莲草全草（Eclipta alba (L.)Hassk）中分得4个三萜化合物，经理化常数测定和光谱（IR，MS，UV，^1HNMR,^13CNMR和^13C-^1H COSY）解析，2个已知的三萜化合物分别为囊酸（echinocystic acid,1）和齐墩果酸（oleanolic acid,2），另2个为新化合物，分别命名为旱莲甙A（ecliptasaponin A,3）和旱莲甙B（ecliptasaponin B,4），Ⅰ和Ⅱ为首次从鳢肠属植物中获得。     

Minimization of photooxidative insult to calf lens protein irradiated with near UV-light in the presence of pigmented glucosides derived from human lens protein

An aqueous solution of a pigmented glucoside associated with human lens protein, 2-amino-3-hydroxyacetophenone-O-beta-D-glucoside (AHA-Glc), was irradiated with near UV-light. The near UV-irradiated glucoside was shown to generate a much lower level of active species of molecular oxygen as compared to the level of the active species generated from the irradiated aglycon, 2-amino-3-hydroxyacetophenone (AHA). This result suggests that the glycon of the glucoside is functioning as a scavenger for active oxygen generated from the aglycon of the irradiated glucoside. Superoxide dismutase (SOD) was shown to remove a large portion of the active oxygen generated from the irradiated AHA, so the bulk of the active species generated is assumed to be superoxide anion. The small portion of active oxygen remains after removal of superoxide anion may include singlet oxygen. The photooxidation of tryptophan residues of calf alpha-crystallin irradiated with near UV-light in the presence of AHA-Glc or AHA was investigated to confirm the role that the glycon plays in diminution of the active species of oxygen generated through the photosensitized aglycon of the glucoside. A decrease with time in the fluorescence intensity of the tryptophan residues irradiated with AHA-Glc was shown to be much slower as compared to the time-dependent decrease with AHA, indicating that the photooxidation proceeds with an increase in accumulation of active oxygen generated through the aglycon and that the glycon of the glucoside deactivates the active species as it is formed in the photodynamic process. Similar effects have also been observed in calf lens crystallin irradiated with either 3-hydroxykynurenine-O-beta-D-glucoside (HKN-Glc) or 3-hydroxykynurenine (HKN). Furthermore, effects of near UV-irradiation on calf lens soluble protein in the presence of AHA-Glc or AHA were studied by monitoring changes in the SDS-PAGE profile of the irradiated protein. Near UV-irradiation with AHA-Glc was shown to bring about a slight change in cross-linking of the polypeptides, while irradiation with AHA was shown to give rise to a significant increase in cross-linking of the polypeptides. In conclusion, pigmented glucoside associated with human lens protein is not only a photosensitizer for near UV-light but also an anti-photooxidant to deactivate active oxygen formed through the in situ photosensitizer, in order that photooxidative insults to lens proteins may be minimized during aging.     

参乌胶囊及其有效成分二苯乙烯苷对老年大鼠海马神经元突触体素表达的影响

目的观察由首都医科大学宣武医院药物研究室自行研制的抗老年性痴呆中药新药参乌胶囊(Shen-wu capsule,SW)及其有效成分何首乌二苯乙烯苷(tetrahydroxystilbene glucoside,TSG)对于老年大鼠海马神经元突触结构和突触体素表达的影响,阐明其防治神经元退行性变的机制。方法选用老年SD大鼠,从21月龄始,分别灌胃给予SW(0.8 g/kg、1.6 g/kg)和TSG(0.03 g/kg、0.06 g/kg)至24月龄。以6月龄大鼠为青年对照,未给药24月龄大鼠为老年对照。应用通道式水迷宫试验检测大鼠学习记忆能力,用电子显微镜观察脑海马神经元突触超微结构,用免疫组织化学染色检测海马神经元突触体素(synaptophysin,SYP)的表达。结果与6月龄青年对照组大鼠相比,24月龄老年大鼠通道式水迷宫试验错误次数明显增多(P<0.01);给予SW和TSG的老年大鼠在高剂量组可见水迷宫错误反应次数显著减少,与老年对照组相比差异具有统计学意义(P<0.01)。电子显微镜结果显示,24月龄老年大鼠神经元突触数量明显减少;而给予TSG大剂量灌胃组突触数量增多,并可见类似于突触球的结构。免疫组织化学染色结果可见24月龄大鼠SYP染色明显变浅,累积光密度值低(P<0.01);而灌胃给予SW和大剂量TSG组大鼠SYP表达量明显升高,差异具有统计学意义(P<0.01)。结论参乌胶囊及其有效成分二苯乙烯苷对于老年大鼠的神经元突触靶位具有较好的疗效,本结果为其在临床用于延缓衰老、改善认知功能提供了实验基础。     

枳壳果皮、核瓤有效成分的比较研究

目的:测定枳壳果皮、核瓤中的主要有效成分含量并进行比较分析,为枳壳综合开发利用提供依据。方法:采用反相高效液相色谱法分别测定枳壳果皮、核瓤中辛弗林和4种黄酮苷的含量。结果:辛弗林、芸香柚皮苷、柚皮苷、橙皮苷、新橙皮苷的进样量分别在0.058～0.696、0.014～4.720、0.017～28.920、0.031～20.520、0.028～18.520μg范围内与各自峰面积积分值呈良好的线性关系(r≥0.9996);平均加样回收率分别为98.21%、97.02%、97.71%、98.55%、98.41%,RSD分别为1.61%、1.98%、2.00%、1.14%、1.47%(n均为6)。结论:枳壳果皮中有效成分的含量总体均大于核瓤。但枳壳核瓤中存在有效化学成分,可考虑进一步综合利用。     

Attachment of rhamnosyl glucoside on quercetin confers potent iron-chelating ability on its antioxidant properties

The pharmacological essence of the natural addition of rhamnosyl glucoside on quercetin that is commonly found in nature in medicinal plants is rather obscure. The present study therefore sought to compare the antioxidant activities of both compounds by comparing their ability to decolourise DPPH radicals, reduce Fe³⁺, chelate Fe²⁺, prevent deoxyribose degradation and inhibit hepatic thiobarbituric acid reactive substances induced by both Fe²⁺ and sodium nitroprusside. The results show that quercetin is generally a more potent antioxidant than its rhamnosyl glucoside derivative (rutin). However, rutin exerted a more potent iron-chelating ability than quercetin which diminishes in a time dependent fashion suggesting why it exhibited a reduced inhibitory effect on lipid peroxidation and deoxyribose degradation under harsh prooxidant assault than quercetin. Taken together, we speculate that rutin may have been produced initially in plants as a possible defense mechanism for protection and survival under oxidative assaults and where both flavonoids are found to co-exist in nature, there is a possible synergy in their antioxidant actions.     

HPLC法测定乌参醒脑滴丸中二苯乙烯苷的含量

目的建立高效液相色谱法测定乌参醒脑滴丸中2,3,5,4＇-四羟基二苯乙烯-2-O-β-D-葡萄糖苷（二苯乙烯苷）含量的方法。方法采用SunFireTM C18（250 mm×4.6 mm,5.0μm）色谱柱,柱温为30℃;以乙腈-水（体积比20∶80）为流动相,流速为1.0 mL.min-1;检测波长为320 nm。结果二苯乙烯苷在12.75～85.0μg.mL-1范围内与峰面积呈良好的线性关系,平均回收率为99.8%,RSD为2.16%。结论该法可用于乌参醒脑滴丸中二苯乙烯苷的含量测定。