Pérez GRM, Vargas SR, García DLM, Dávila BL

Language: Spanish
References: 16
Page: 134-139
PDF size: 204.83 Kb.

ABSTRACT

The isoflavones isolated from heartwood of Eysenhardtia polystachya: 7-hydroxy-2’, 4’, 5’-trimethoxyisoflavone [A] y 7-hydroxy-4’-etoxyisoflavone [B] showed significant dose dependent protection against urolithiasis induced by zinc disc implantation in albino rats. Objective: 1) Evaluated the ability of isoflavones to inhibit calcium oxalate and calcium phosphate in normal, of adults with history of urinary stones (abnormal) and artificial urines. 2) Evaluated the effect of isoflavones on the crystallization of calcium oxalate (COM) at conditions of constant supersaturation. Material and methods: The activity of normal urine was measured (nephelometric procedure) and compared with that of artificial urines and abnormal urine having identical concentrations of the isoflavones. The inhibitory activity of COM crystal growth in the presence of the isoflavones were measured at conditions of constant solution supersaturation as function of relative supersaturation with respect to COM. Results: The change of oxalate concentration in urines normal, abnormal and artificial treated with isoflavone [A] was reduced in 64.23, 38.6 y 22.43% respectively. When the compound [B] was added reduced in 55.95, 18.62 y 20.32% respectively. The activity of compounds [A] on the formation of phosphate for normal abnormal and artificial urines were of 70.31, 44.57 y 38.61% respectively. With the added of compound [B] were reduced in 63.8, 40.61 y 30.16% respectively. The compounds [A] and [B] produced significant lowering growth rate and nucleation rate of calcium oxalate crystals at concentration of 4.6 X 10-4 M exerted a maximum response of 89% and 72% reduction respectively. Conclusions: The isolated isoflavones [A] and [B] from E. polystachya work as inhibitors in the formation and crystal growth of COM and phosphate and may protect against stone formation by reducing the degree of aggregation and the size of particles precipitated. These compounds can be recomended as a preventive medicine in renal stone formation.

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