Effects of commercial citrate‐containing juices on urolithiasis in a Drosophila model

Abstract

Diet modification plays an important role in nephrolithiasis. Development of an easy, ready-to-use beverage such as a commercial juice drink to use as a preventive treatment for renal calculi formation would be widely welcomed. We previously developed a novel Drosophila model for the study of nephrolithiasis. It provides a new well-established drug discovery platform for this common disease. In our current study, we used the Drosophila model to investigate the preventive effects of various commercial juices as potential treatments for nephrolithiasis. Our results showed that apple, cranberry, orange, and pomegranate juices failed to reduce calcium oxalate (CaOx) crystal formation, whereas our positive control-potassium citrate (K-citrate)-significantly prevented CaOx crystal formation. Unlike the commercial fruit juices that were tested, the administration of K-citrate significantly ameliorated the ethylene glycol (EG)-induced life-span reduction in treated flies. These results indicate that EG-induced CaOx nephrolithiasis in Drosophila can be prevented by K-citrate, but not by commercial citrate-containing juices. However, the inhibitory capability of citrate-containing juices to reduce renal stone formation in humans requires further elucidation.

An Emerging Translational Model to Screen Potential Medicinal Plants for Nephrolithiasis, an Independent Risk Factor for Chronic Kidney Disease

“…We used wild-type male D. melanogaster fed with 0.5% EG as lithogenic group and D. melanogaster fed without lithogenic agent as control group in this study for the evaluation of CaOx crystal formation [17–19]. In brief, flies were bred in plastic vials containing a medium of yeast, corn syrup, and agar.…”

“…Recently, we have developed a fruit fly ( Drosophila melanogaster ) model for translational research of urolithiasis and applied this model to the evaluation of agents that may have potential antilithic effect [17–19]. The Malpighian tubule of the fruit fly has a function similar to the human kidney [20–23].…”

“…The crystals were easily observed under polarized microscopy, and the crystal formation rate can then be evaluated [17–19]. For example, a test for the effect of melamine on crystal formation in Drosophila was performed.…”

“…In a previous study by Ho et al, it was found that potassium citrate could prevent crystal formation in EG-induced CaOx nephrolithiasis in Drosophila. No inhibitory capability of commercial citrate-containing juice was observed for CaOx crystal formation in the Malpighian tubules of the fly [19]. Therefore, this model can be further used as a rapid screening method to test any drugs that have a potential antilithic effect.…”

Garcinia cambogia extract removes calcium oxalate kidney stones in both genetic and non-genetic Drosophila models of nephrolithiasis

“…The Drosophila calcium oxalate stone model has been used to screen traditional Chinese medicinal plants for the treatment of nephrolithiasis (Ho et al, 2013). Chen et al showed that commercial juices, such as apple, cranberry, orange, and pomegranate juices, failed to prevent calcium oxalate crystal formation in Drosophila nephrolithiasis model.…”