# Litholytic Activities of Natural Bioactive Compounds and Their Mechanism Insights
## 5 Litholytic Activity of Other Compounds
### In Vivo Investigations  
The nephrolithiasis effect of the in vivo approach of taraxasterol, betulin, lupeol, khellin, visnagin, crocin, piperine, berberine, oleanolic acid, vitamin E, selenium, DADS, DATS, and rottlerin (Figure 5) was investigated by several researchers (Table 4) using several animal models, including oral administration of EG, EG with ammonium chloride, pyridoxine-deficient diet (PDD), or using the implantation of a foreign body (zing disc and glass bead) to mimic the etiology of urinary stone formation in humans [46; 48; 49; 44; 46]. Terpenoids, bioactive compounds widely distributed in nature, have specific and multiple molecular targets, such as the activation of NF-kB transcription factors to inhibit the inflammatory signaling pathways [61], and the decrease in mitochondrial membrane potential (\(\Delta\)Vm) in anticancer pathways [62]. Recently, thanks to new technologies and molecular biology, several researchers have reported, on the one hand, the nephrolithiasis efficacy of bioactive compounds and, on the other hand, the mechanistic pathways of these terpenoids. The authors of [50] have tested the effect of lupeol, a pentacyclic triterpene, for 16 weeks on urolithiasis induced by a glass bead (15-18 mg) implantation in rats. This study showed that lupeol (10, 25, or 50 mg/kg) significantly reduced, in a dose-dependent manner, the weight of urolith formed in preventive treatment compared to curative treatment (20-95% and 15.5-55%, respectively, for the weight of urolith). In addition, at 50 mg/kg, the urinary levels of calcium, inorganic phosphate, and oxalate (the major calculogenic substances) were very significantly reduced compared to lithiasis rats (7.44 vs. 11.68 mg/dL, 47.06 vs. 59.8 mg/dL, and 5.53 vs. 7.2 mg/dL, respectively, in preventive treatment and 8.02 vs. 11.68 mg/dL, 49.74 vs. 59.83 mg/dL, and 7.21 vs. 8.89 mg/dL, respectively, in curative treatment). The authors suggested that this reduction is mediated by dissolution or demineralization of the preformed mineral phase and also by the prevention of their deposition in the urinary bladder. After one year, another study was carried out by [51] on the use of lupeol against a hyperovaluric Wistar strain induced by 2% ammonium oxalate. At 25 mg/kg for 15 days, the level of urinary oxalate was reduced compared to a lithogenic Wistar strain (8.15 vs. 13.63 mg/day), while creatinine, citric acid, and glycosaminoglycans were normalized (10.36 vs. 13.20 mg/day, 1.99 vs. 2.83 mg/day, and 3.39 vs. 4.23 mg/day, respectively). In addition, the major oxalate-synthesizing enzyme (LDH), the enzymes specific for the renal proximal tubules (ALP and gamma glutamyl transferase (\(\gamma\)-AGT)), and the lysosomal marker enzymes (\(\beta\)-glucuronidase and N-acetyl \(\beta\)-D glucosaminidase (NAG)) were significantly reduced in urine compared to nephrolithiasis rats (0.39 vs. 0.73 moles of pyruvate released/mg creatinine/day, 1.15 vs. 2.86 moles of phenol released/mg creatinine/day, 5.07 vs. 8.33 moles of p-nitroaniline released/mg creatinine/day, and 0.74 vs. 1.39 moles of p-nitroaniline released/mg creatinine/day, respectively). In 2000, the same group [52] investigated, in vivo, the effect of lupeol isolated from the stem bark powder of _Crateeva unreala_ on urolithiasis induced by the insertion of a zinc piece in rats followed by 2% ammonium oxalate. From this experience, lupeol at 35 mg/kg restored non-enzyme antioxidant levels (GSH (4.56 vs. 4.68 ug/mg protein), TSH (11.02 vs. 12.25 ug/mg protein), NPSH (2.91 vs. 3.26 ug/mg protein), vitamin C (1.97 vs. 2.13 ug/mg protein), and vitamin E (0.45 vs. 0.48 ug/mgprotein)) and antioxidant enzymes (SOD (6.34 vs. 6.54 units/min/mg protein), GPx (9.57 vs. 10.30 units/min/mg protein), and CAT (151.13 vs. 170.11 units/min/mg protein)) in the kidneys compared to normal rats. At the same time, lupeol improved glutathione-related enzymes (glutathione-S-transferase (GST), glutathione reductase (GR), and glucose-6-phosphate dehydrogenase (G6 PD)) in the kidneys compared to lithiasis rats.