Inhibitory effects of taraxasterol and aqueous extract of Taraxacum officinale on calcium oxalate crystallization: in vitro study.

OBJECTIVE: We investigated and compared the effects of taraxasterol, aqueous extract of T. officinale (AET) aerial part, and potassium citrate (PC) on calcium oxalate (CaOx) crystallization in vitro. MATERIALS AND METHODS: CaOx crystallization was induced by adding sodium oxalate to synthetic urine. Taraxasterol (2.5, 5, 7.5 and 12.5 µg/mL), extract (1, 2, 4 and 8 mg/mL), and PC (100, 150, 200 and 350 mg/mL) were subjected to anti-crystallization activities. The absorbance and %inhibition of nucleation of CaOx crystals were evaluated by spectrophotometer at 2, 4, 6, 8, 10, 20, 30, 40, 50 and 60 min and the number and morphology of crystals were studied by light microscopy after 60 min. RESULTS: Presence of taraxasterol, extract and PC decreased absorbance in experimental samples compared to control, significantly. The nucleation of crystals is inhibited by taraxasterol, extract, and PC (26-64, 55-63 and 60-70%, respectively). The number of CaOx crystals were decreased in presence of taraxasterol (p < .01), extract (p < .001), and PC (p < .001) in a dose-dependent manner. Presence of taraxasterol, extract, and PC decreased the number of CaC2O4 monohydrate, while increased CaC2O4 dihydrate crystals, significantly. Also, the diameter of CaC2O4 dihydrate crystals was decreased in presence of taraxasterol, extract and PC, significantly. CONCLUSIONS: This research indicated that taraxasterol and extract have anti-crystallization activities and effectiveness of the extract is more potent than taraxasterol. It could be because of another constituent in the extract with the synergistic effect.

Antiurolithiatic effect of the taraxasterol on ethylene glycol induced kidney calculi in male rats.

Taraxasterol is one of the important constituents of Taraxacum officinale L. (Compositae) with antioxidant potential. The present study was designed to evaluate and compare the antiurolithiatic effects of taraxasterol and potassium citrate in the ethylene glycol induced urolithiatic rat. Urolithiasis was induced by ammonium chloride and ethylene glycol in adult male rats. Taraxasterol (2, 4 and 8 mg/kg) and potassium citrate (2.5 g/kg) were treated for 33 days by gavage. Then, the animals were anesthetized and weighted and blood, urine, liver and kidney sampling were done. The kidney sections were prepared by hematoxylin & eosin staining. The liver and kidney coefficients, urine pH, calcium, magnesium, oxalate and citrate levels, serum albumin, calcium and magnesium levels, serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, superoxide dismutase and glutathione peroxidase activities in serum, kidney and liver, number of calcium oxalate crystal deposits, score of crystal deposits, score of histopathological damages and score of inflammation in kidney sections were evaluated. The results showed that taraxasterol decreased liver and kidney coefficients (p < 0.001), serum calcium (p < 0.01) level, serum alanine aminotransferase (p < 0.001), aspartate aminotransferase (p < 0.001), lactate dehydrogenase (p < 0.05) activities, urine magnesium (p < 0.05) and oxalate (p < 0.001) levels, number of crystal deposits (p < 0.001), score of crystal deposits (p < 0.01), score of histopathological damages (p < 0.001) and score of inflammation (p < 0.01) in kidney sections, while increased urine pH (p < 0.01), calcium (p < 0.001) and citrate (p < 0.05), serum magnesium (p < 0.001) and albumin (p < 0.01) levels, superoxide dismutase and glutathione peroxidase in serum (p < 0.01), kidney (p < 0.05 and p < 0.001, respectively) and liver (p < 0.01 and p < 0.001, respectively) tissue homogenates in treated urolithiatic rats in comparison to the control urolithiatic rats. The effect of potassium citrate is the same as taraxasterol in treated urolithiatic rats. In conclusion, the effect of taraxasterol could be by improving liver function, changing serum and urine parameters, maintaining the antioxidant environment, reducing crystal deposition, excretion of small deposits from kidney and reducing the chance of them being retained in the urinary tract.