Nephroprotective Effects of Sunkist Orange (Citrus sinensis (L.) Osbeck) Peel Nanoparticles in Diabetic Wistar Rats (Rattus norvegicus)

This exploratory laboratory study assessed renal and oxidative responses to Sunkist orange peel (Citrus sinensis (L.) Osbeck) granules, designated nanoparticle granules in the protocol. A post-test-only control group design included 24 male Wistar rats allocated to six groups (four per group): non-induced control, alloxan-only control, metformin, and granules at 100, 200, or 300 mg/kg body weight (BW). After seven days of acclimatization, five groups received alloxan monohydrate (120 mg/kg BW, intraperitoneally) on one induction day; oral treatment continued for 21 days. The numerical glucose criterion and interval used to confirm diabetes were not documented. Compared with the alloxan-only group, mean superoxide dismutase (SOD) was highest at 100 mg/kg BW (0.545 versus 0.317 U/mL; 71.9% higher), whereas mean malondialdehyde (MDA) was lowest at 300 mg/kg BW (0.464 versus 0.740 nmol/mL; 37.3% lower). Mean urea was lowest at 200 mg/kg BW (28.00 versus 92.00 mg/dL; 69.6% lower) but rose to 61.00 mg/dL at 300 mg/kg BW. Overall differences were reported for SOD and MDA (ANOVA, both p < 0.001), urea (p = 0.013), morphology (p = 0.002), and histopathology (p < 0.001). No pairwise difference in urea or renal injury scores remained significant after Bonferroni correction. Responses were not uniformly dose-dependent. These preliminary, endpoint-specific trends do not establish nephroprotective efficacy or dose superiority; interpretation is limited by the small sample, short duration, incomplete glycemic documentation, and incomplete formulation and assay documentation.