Atmani F, Khan S R
Laboratory of Cellular Physiology and Pharmacology, University Mohammed the First, Faculty of Sciences, Department of Biology, Oujda-Morocco.
BJU Int. 2000 Apr;85(6):621-5. doi: 10.1046/j.1464-410x.2000.00485.x.
To evaluate the effectiveness of an extract obtained from Herniaria hirsuta on calcium oxalate crystallization in vitro. Materials and methods An extract was prepared from H. hirsuta at different concentrations (0.0625-1 mg/mL). Crystallization was induced in whole normal human urine samples in the absence or presence of the extract. Crystals generated in the urine were harvested and analysed by scanning electron microscopy. The nucleation and aggregation of calcium oxalate crystals were measured separately using spectrophotometric methods. The nucleation rate was followed at 620 nm after mixing calcium chloride and sodium oxalate solution at 37 degrees C, with stirring. The induction time in the presence of herb extract was compared with that of the control. The aggregation rate was also followed at 620 nm in a buffered solution containing calcium oxalate monohydrate crystals after stopping the stirring. The rate was evaluated by comparing the slope of turbidity in the presence of the extract with that of the control.
The herb extract promoted the precipitation of calcium oxalate particles in whole urine. SEM showed that there were more crystals with increasing concentration of extract but that they were proportionally smaller. Moreover, the presence of herb extract favoured the formation of calcium oxalate dihydrate rather than monohydrate crystals. The extract inhibited calcium oxalate crystal aggregation. In an independent experiment, the herb extract was dialysed and filtered before inducing crystallization, to eliminate any fibrous particles and oxalate. The treated herb extract promoted more crystallization, especially at high concentrations.
An extract of H. hirsuta promoted the nucleation of calcium oxalate crystals, increasing their number but decreasing their size. It also promoted the formation of calcium oxalate dihydrate crystals, despite the presence of calcium oxalate monohydrate particles. The extract may contain substances that inhibit calcium oxalate crystal aggregation. These properties of H. hirsuta might be beneficial in preventing kidney stone formation.
评估多毛墙草提取物在体外对草酸钙结晶的作用效果。材料与方法 制备不同浓度（0.0625 - 1mg/mL）的多毛墙草提取物。在有无该提取物的情况下，诱导正常人全尿样本中产生结晶。收集尿液中生成的晶体，并用扫描电子显微镜进行分析。分别采用分光光度法测量草酸钙晶体的成核和聚集情况。在37℃搅拌条件下，将氯化钙和草酸钠溶液混合后，于620nm处跟踪成核速率。将草药提取物存在时的诱导时间与对照组进行比较。在停止搅拌后，于含有一水合草酸钙晶体的缓冲溶液中，同样在620nm处跟踪聚集速率。通过比较提取物存在时与对照组的浊度斜率来评估该速率。
草药提取物促进了全尿中草酸钙颗粒的沉淀。扫描电子显微镜显示，随着提取物浓度增加，晶体数量增多，但尺寸相对变小。此外 , 草药提取物的存在有利于二水草酸钙而非一水合草酸钙晶体的形成。该提取物抑制草酸钙晶体聚集。在一项独立实验中，在诱导结晶前对草药提取物进行透析和过滤，以去除任何纤维颗粒和草酸盐。处理后的草药提取物促进了更多结晶，尤其是在高浓度时。
多毛墙草提取物促进了草酸钙晶体的成核，增加了晶体数量但减小了其尺寸。尽管存在一水合草酸钙颗粒，它还促进了二水草酸钙晶体的形成。该提取物可能含有抑制草酸钙晶体聚集的物质。多毛墙草的这些特性可能有助于预防肾结石的形成。
