Inhibitory Effects Of Chinese Traditional Medicine On Calcium Oxalate Crystallization

Urinary stone is the product of abnormal biomineralization and was mostly composed of calcium oxalate, i.e. calcium oxalate monohydrate (COM). Scientists usually simulate the formation of calcium oxalate stone in vitro because it is difficult to study the formation process of the stone in organism.Chinese Traditional Medicine has been used to cure urinary calculi for thousands of years and much progress was made in treating urolithiasis, but the therapy mechanism of the Chinese Traditional Medicine is not yet clearly understood. In order to prevent and cure urinary stone, it is very important to simulate the formation process of calculus and study the inhibitory effect of Chinese Traditional Medicine extract on calcium oxalate crystallization in vitro. In this paper, we investigated the effects of the extracts of some Chinese Traditional Medicine, such as Fuctus Mutne, Hawthorn, Lysimachia christinae Hance and Semen Astragali Complanali, on preventing the formation of calcium oxalate stone, and the possible inhibition mechanism of above medicines on calcium oxalate was also discussed.The inhibitory effect of the extract of Fuctus Mume on the crystallization of calcium oxalate in aqueous solution was studied, and the crystals were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results showed that the calcium oxalate monohydrate (COM) was the dominant phase in pure water while calcium oxalate dehydrate (COD) crystal alone appeared in the extract of Fuctus Mume. It is known that the affinity of COD to renal tubule cell membranes is weaker than that of COM, and COD is easier to be ejected out along with urine than COM, suggesting that the extract of Fuctus Mume could inhibit the crystallization of calcium oxalate monohydrate, and the inhibiting ability increases along with the increase of the extract concentration. The kinetic process of the crystal growth was studied by monitoring the electrical conductivity of solution and the result suggested that the extract of Fuctus Mume mainly inhibit the nucleation...