Objective: Kidney stone formers have a high rate of stone recurrence after kidney stone removal surgery and there is no effective medication for treatment. Hydroxycitric acid (HCA), which is the major component of Garcinia cambogia extract, can dissolve calcium oxalate crystals in vitro, suggesting that Garcinia cambogia could be used to treat calcium oxalate kidney stone. In this study, we used the Drosophila kidney disease model to evaluate the effect of Garcinia cambogia on the prevention and removal of calcium oxalate stones in vivo.
Materials and methods: Flies were reared in fly food containing different concentrations of GCE for one week. The effect of GCE on preventing the formation of calcium oxalate stone was examined. WT and v-ATPase gene RNAi knockdown flies were reared in fly food with 0.3% NaOx for one week, then fed different concentrations of GCE for one week. The effect of GCE on the removal of calcium oxalate stone was examined.
Results: Garcinia cambogia extract dissolves calcium oxalate crystals from Malpighian tubules in both genetic and non-genetic Drosophila kidney stone models compared to citric acid. Hydroxycitric acid also directly dissolves calcium oxalate crystals in Drosophila Malpighian tubules ex vivo.
Conclusions: Garcinia cambogia extract removes calcium oxalate kidney stones from Drosophila Malpighian tubules via directly dissolving calcium oxalate stones by HCA. Our study strongly suggests that clinical-grade Garcinia cambogia extract could be used to treat patients with nephrolithiasis in the future.