Garcinia cambogia Extract Alleviates Calcium Oxalate Kidney Stones and Is Associated with Gut Microbiota-Short Chain Fatty Acid Modulation in Rats
Background: Calcium oxalate (CaOx) kidney stones are a common urological disorder associated with a high recurrence rate. Garcinia cambogia extract (GCE), a botanical extract rich in hydroxycitric acid, exhibits antioxidant and metabolic regulatory activities, yet its potential role in CaOx nephrolithiasis remains insufficiently characterized. Methods: Fifty male Sprague-Dawley rats were randomly divided into five groups: control, CaOx model, CaOx + low-dose GCE (100 mg/kg/day), CaOx + medium-dose GCE (300 mg/kg/day), and CaOx + high-dose GCE (900 mg/kg/day). After predefined exclusions and quality control screening, eight rats per group were included in the final analysis. CaOx nephrolithiasis was induced by 5% L-hydroxyproline administration for 28 days. GCE or vehicle was given by oral gavage in a preventive/early intervention regimen. Renal histology, ultrasound-assessed stone burden, renal biochemical indices, oxidative stress markers, gut microbiota composition, and short-chain fatty acid (SCFA) levels were evaluated. Results: Compared with the CaOx model group, GCE treatment ameliorated renal biochemical parameters, alleviated oxidative stress, and reduced ultrasound-detected stone burden. The mean stone area measured by ultrasound decreased from 5.67 ± 0.69 mm² in the CaOx model group to 4.12 ± 0.56, 3.02 ± 0.46, and 1.98 ± 0.34 mm² in the low-, medium-, and high-dose GCE groups, respectively. Histological analysis revealed a marked reduction in crystal deposition in the low- and medium-dose groups, while the high-dose group exhibited the lowest macroscopic stone burden on ultrasound. GCE treatment also partially restored microbial diversity, modulated gut microbiota composition, and elevated fecal SCFA levels. Conclusions: In this rat model, GCE reduced CaOx stone burden, improved renal function, and mitigated oxidative stress. The accompanying alterations in gut microbiota composition and SCFA production were associated with these renoprotective effects but do not establish microbiota-mediated causality. These findings support further mechanistic evaluation of GCE as a candidate for kidney stone prevention.
Background: Calcium oxalate (CaOx) kidney stones are a common urological disorder associated with a high recurrence rate. Garcinia cambogia extract (GCE), a botanical extract rich in hydroxycitric acid, exhibits antioxidant and metabolic regulatory activities, yet its potential role in CaOx nephrolithiasis remains insufficiently characterized. Methods: Fifty male Sprague-Dawley rats were randomly divided into five groups: control, CaOx model, CaOx + low-dose GCE (100 mg/kg/day), CaOx + medium-dose GCE (300 mg/kg/day), and CaOx + high-dose GCE (900 mg/kg/day). After predefined exclusions and quality control screening, eight rats per group were included in the final analysis. CaOx nephrolithiasis was induced by 5% L-hydroxyproline administration for 28 days. GCE or vehicle was given by oral gavage in a preventive/early intervention regimen. Renal histology, ultrasound-assessed stone burden, renal biochemical indices, oxidative stress markers, gut microbiota composition, and short-chain fatty acid (SCFA) levels were evaluated. Results: Compared with the CaOx model group, GCE treatment ameliorated renal biochemical parameters, alleviated oxidative stress, and reduced ultrasound-detected stone burden. The mean stone area measured by ultrasound decreased from 5.67 ± 0.69 mm² in the CaOx model group to 4.12 ± 0.56, 3.02 ± 0.46, and 1.98 ± 0.34 mm² in the low-, medium-, and high-dose GCE groups, respectively. Histological analysis revealed a marked reduction in crystal deposition in the low- and medium-dose groups, while the high-dose group exhibited the lowest macroscopic stone burden on ultrasound. GCE treatment also partially restored microbial diversity, modulated gut microbiota composition, and elevated fecal SCFA levels. Conclusions: In this rat model, GCE reduced CaOx stone burden, improved renal function, and mitigated oxidative stress. The accompanying alterations in gut microbiota composition and SCFA production were associated with these renoprotective effects but do not establish microbiota-mediated causality. These findings support further mechanistic evaluation of GCE as a candidate for kidney stone prevention.