Freitas A M, Schor N, Boim M A
Nephrology Division, Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, Brazil.
BJU Int. 2002 Jun;89(9):829-34. doi: 10.1046/j.1464-410x.2002.02794.x.
To evaluate the effect of an aqueous extract of Phyllanthus niruri (Pn), a plant used in folk medicine to treat lithiasis, on the urinary excretion of endogenous inhibitors of lithogenesis, citrate, magnesium and glycosaminoglycans (GAGs).
The effect of chronic (42 days) administration of Pn (1.25 mg/mL/day, orally) was evaluated in a rat model of urolithiasis induced by the introduction of a calcium oxalate (CaOx) seed into the bladder of adult male Wistar rats. The animals were divided into four groups: a sham control (16 rats); a control+Pn (six); CaOx+water instead of Pn (14); and CaOx+Pn (22). Plasma and urine were collected after 42 days of treatment for biochemical analysis and the determination of urinary excretion of citrate, magnesium and GAGs. The animals were then killed and the calculi analysed.
The creatinine clearance or urinary and plasma concentrations of Na+, K+, Ca2+, oxalate, phosphate and uric acid were unaffected by Pn or the induction of lithiasis. Treatment with Pn strongly inhibited the growth of the matrix calculus and reduced the number of stone satellites compared with the group receiving water. The calculi were eliminated or dissolved in some treated animals (three of 22). The urinary excretion of citrate and magnesium was unaffected by Pn treatment. However, the mean (sd) urinary concentration of GAGs was significantly lower in rats treated with CaOx+Pn, at 5.64 (0.86) mg/g creatinine, than when treated with CaOx + water, at 11.78 (2.21) mg/g creatinine. In contrast, the content of GAGs in the calculi was higher in the CaOx + Pn rats, at 48.0 (10.4) g/g calculus, than in the CaOx + water group, at 16.6 (9.6) g/g calculus.
These results show that Pn has an inhibitory effect on crystal growth, which is independent of changes in the urinary excretion of citrate and Mg, but might be related to the higher incorporation of GAGs into the calculi.
评估民间用于治疗结石症的植物——叶下珠水提取物(Pn)对结石形成内源性抑制剂、柠檬酸盐、镁和糖胺聚糖(GAGs)尿排泄的影响。
在成年雄性Wistar大鼠膀胱内植入草酸钙(CaOx)种子诱导形成尿石症的大鼠模型中,评估长期(42天)口服Pn(1.25mg/mL/天)的效果。动物分为四组:假手术对照组(16只大鼠);对照组 + Pn(6只);CaOx + 水替代Pn组(14只);CaOx + Pn组(22只)。治疗42天后收集血浆和尿液进行生化分析,并测定柠檬酸盐、镁和GAGs的尿排泄量。然后处死动物并分析结石。
肌酐清除率或尿及血浆中Na⁺、K⁺、Ca²⁺、草酸盐、磷酸盐和尿酸的浓度不受Pn或结石形成诱导的影响。与接受水的组相比,Pn治疗强烈抑制了基质结石的生长并减少了结石卫星灶的数量。在一些接受治疗的动物中(22只中有3只)结石被清除或溶解。Pn治疗对柠檬酸盐和镁的尿排泄无影响。然而,CaOx + Pn治疗的大鼠中GAGs的平均(标准差)尿浓度显著低于CaOx + 水治疗的大鼠,分别为5.64(0.86)mg/g肌酐和11.78(2.21)mg/g肌酐。相反,CaOx + Pn大鼠结石中GAGs的含量高于CaOx + 水组,分别为48.0(10.4)g/g结石和16.6(9.6)g/g结石。
这些结果表明,Pn对晶体生长具有抑制作用,这与柠檬酸盐和镁的尿排泄变化无关,但可能与更多的GAGs掺入结石有关。