RE-HPLC测定积雪草中积雪草甙、羟基积雪草甙的含量

目的测定不同产地的中药积雪草甙和羟基积雪草甙的含量.方法采有RE-HPLC法进行测定.结果不同产地的积雪草中积雪草甙和羟基积雪草甙的含量有很大差异.结论方法简便,准确灵敏.     

积雪草提取纯化工艺的研究

目的研究积雪草的提取纯化工艺。方法采用正交试验进行工艺优化,薄层色谱扫描法测定羟基积雪草苷含量。结果提取工艺最佳条件为:水提取2次,第1次加10倍量水提取2h,第2次加8倍量水提取1.5h。纯化工艺最佳条件为壳聚糖用量0.4mL/g,药液浓缩比例1.2:1,絮凝温度70℃。结论本方法可节省原料,缩短工时,降低成本,利于工业化大生产。     

羟基积雪草苷在大鼠肠内吸收的研究

目的 研究羟基积雪草苷在大鼠肠段各段的吸收特征,探究其在肠道的吸收机制,为设计药物的剂型和给药途径提供理论基础。方法 利用大鼠在体循环肠灌流模型和方法,探明羟基积雪草苷的肠道吸收部位和吸收特征,以及不同表面活性剂对其肠吸收的影响。结果/b> 羟基积雪草苷在大鼠小肠段吸收强于大肠段,其吸收速率回肠＞空肠≥十二指肠＞结肠。而不同浓度的羟基积雪草苷溶液回肠吸收率和吸收速率常数无显著差异。在3种不同表面活性剂中,聚山梨酯-80对羟基积雪草苷的回肠吸收具有显著的促进作用。结论 羟基积雪草苷的肠吸收主要集中在小肠中段,且吸收机制推测为被动扩散,表面活性剂聚山梨酯-80可以促进其回肠吸收。     

羟基积雪草苷的药理学作用及机制研究进展

羟基积雪草苷是伞形科植物积雪草的有效组分之一。研究表明,羟基积雪草苷的药理学作用非常广泛,它在临床上被用于烧伤性瘢痕、皮肤增白、抗炎抗氧化、抗抑郁症、抗肿瘤,防治冠心病、心肌梗死、脑血栓、脑梗死,增强记忆等。本文通过检索近几年国内外相关文献,对其药理学作用及机制的最新研究进展进行综述,以期为羟基积雪草苷的临床应用与开发提供参考。     

羟基积雪草苷对转基因肌萎缩侧索硬化小鼠的治疗作用

目的探讨羟基积雪草苷对铜锌超氧化物歧化酶(Cu,Zn superox ide d ism u tase,SOD 1)-G 93A突变肌萎缩侧索硬化(am yotroph ic latera l scleros is,ALS)小鼠的治疗作用。方法通过行为学和组织学测定,观察羟基积雪草苷对SOD 1-G 93A突变ALS小鼠发病时间、生存时间、运动功能变化和神经元病理改变的影响。结果羟基积雪草苷(61.1±11.0)和(185.6±18.7)m g/(kg.d)在小鼠日龄70 d时开始给药至死亡,能分别延长SOD 1-G 93A突变ALS小鼠的生存时间11.4和9.4 d,但对发病时间无影响;同时(61.1±11.0)m g/(kg.d)组小鼠在肌力缓慢下降期运动功能降低减缓,与对照组比较差异显著(P<0.05)。120 d时L 2~5组织切片显示两治疗组脊髓前角运动神经元数明显高于SOD 1-G 93A对照组(P<0.05),多数运动神经元胞浆中仍有尼氏体存在。结论羟基积雪草苷对SOD 1-G 93A突变转基因小鼠运动神经元变性有保护作用,能延长小鼠的生存时间。     

Factors affecting the content of pentacyclic triterpenes in Centella asiatica raw materials

Context: Pentacyclic triterpenes, mainly, asiatic acid, madecassic acid, asiaticoside, and madecassoside are the active constituents of Centella asitica (L.) Urban. (Apiaceae). These compounds possess various pharmacological activities that have been shown to assist with wound healing and brain enrichment.

Objective: Determination of these active pentacyclic triterpenes in extracts from the various parts of C. asiatica plants harvested at different times of the year and grown in different environments.

Materials and methods: The separate plant parts selected were leaves, stolons, petioles, flowers, fruits, and nodes with roots. Dried powder from each part was extracted with ethanol by microwave-assisted extraction and subjected to determination of their content of the four pentacyclic triterpenes using a HPLC method. The effects of the places of cultivation as well as harvesting periods on the content of the four pentacyclic triterpenes in the extracts were also determined.

Results and discussion: Among the various parts of C. asiatica, the leaves contained the highest amount of pentacyclic triterpenes with a total content of pentacyclic triterpenes of 19.5 mg/g dry powder. However, the contents of the pentacyclic triterpenes in C. asiatica varied according to the place of cultivation and the harvesting period. C. asiatica collected from Trang, Thailand gave the highest content of total pentacyclic triterpenes (37.2 mg/g dry powder) when harvested in March, while those collected from Songkhla, Thailand gave the highest value (37.4 mg/g dry powder) when collected in December. C. asiatica collected from Nakornsrithammarat and Ratchaburi, Thailand gave the lowest content of total pentacyclic triterpenes in all experimental harvesting periods.     

HPLC法测定积雪草配方颗粒中羟基积雪草苷和积雪草苷含量

目的 建立积雪草配方颗粒中羟基积雪草苷和积雪草苷的HPLC含量测定方法。方法 色谱柱为UltimateAQ-C₁₈ 柱（4.6 mm×250 mm,5 μm）,以乙腈（A）-2 mmol/Lβ-环糊精溶液为流动相进行梯度洗脱（0~30 min： 21% A→23% A;30~60 min：23% A→25% A）,流速1.0 ml/min,柱温30 ℃,检测波长205 nm。结果 羟基积雪草苷和积雪草苷分别在0.187 7~3.754 μg和0.184 3~3.686 μg范围内与峰面积呈良好的线性关系（r>0.999 5）。经专属性、重复性、精密度、加样回收率、稳定性实验,结果均符合《中华人民共和国药典（2015年版）》方法验证的要求。结论 该含量测定方法适用于积雪草配方颗粒中羟基积雪草苷和积雪草苷的含量检测。     

积雪草总苷及其制剂的含量研究.Ⅰ.积雪苷霜软膏中积雪草苷和羟基积雪草苷的HPLC法测定

建立了流动相添加剂-HPLC法测定积雪苷霜软膏中积雪草苷和羟基积雪草苷的含量.采用C_(18)色谱柱,以乙腈-水(30:70,添加β-环糊精4.54 g/L)为流动相,检测波长204nm.积雪草苷和羟基积雪草苷在0.2～20μg范围内线性关系良好,平均回收率为99.20%和98.90%,RSD为1.06%和1.17%.     

Madecassoside Ameliorates Bleomycin‐Induced Pulmonary Fibrosis in Mice by Downregulating Collagen Deposition

This study aimed to explore the protective effects of madecassoside (Mad), a triterpenoid saponin isolated from Centella asiatica herbs, on experimental pulmonary fibrosis (PF) and underlying mechanisms. PF model was established in mice by endotracheal instillation with bleomycin (5 mg/kg). Mice were orally administered with Mad (10, 20, 40 mg/kg) and prednisone (5 mg/kg) for 7 or 21 days. Mad (20, 40 mg/kg) significantly improved lung pathological changes and reduced collagen deposition. In the aspect of collagen synthesis, Mad (20, 40 mg/kg) reduced the expressions of α‐smooth muscle actin and transforming growth factor‐β1 (TGF‐β1), and inhibited the phosphorylations of Smad2 and Smad3 in the lung tissues. However, in vitro, Mad showed little effect on TGF‐β1‐induced phosphorylation of either Smad2 or Smad3 in primary mouse lung fibroblasts. Moreover, Mad (20, 40 mg/kg) attenuated oxidative damage and inflammation presented at the early stage of PF, evidenced by reduced total leukocytes in the bronchoalveolar lavage fluid, decreased myeloperoxidase activity and malondialdehyde level, and increased super‐oxide dismutase activity and glutathione level in lung tissues. On the other hand, Mad (40 mg/kg) elevated the matrix metalloproteinase 1/tissue inhibitor of metalloproteinase 1 ratio in lung tissues of PF mice mainly by downregulating tissue inhibitor of metalloproteinase 1 expression. The present study demonstrated that Mad can ameliorate PF by preventing the deposition of extracellular matrix, which might be achieved mainly through attenuating inflammation and oxidative stress and consequent TGF‐β1 overexpression. Copyright © 2014 John Wiley & Sons, Ltd.