<![CDATA[Diabetes mellitus remains an expanding metabolic burden, and Indonesia ranks fifth globally with an estimated 10.7 million cases in 2019. Chronic hyperglycaemia damages the kidneys and pancreas through oxidative stress pathways, which keeps plant-derived antioxidants under active investigation as adjunct therapy. Red betel leaf (Piper crocatum) contains flavonoids and alkaloids that inhibit α-glucosidase in vitro, yet histopathological evidence on target organs remains limited and inconsistently reported. This experimental study evaluated the effect of boiled red betel leaf water at concentrations of 25%, 50%, 75%, and 100% on renal histopathology (tubular cell size and glomerular diameter) and pancreatic histopathology (nuclear and cytoplasmic clarity of the islets of Langerhans) in alloxan-induced diabetic mice (Mus musculus), given a single dose of 100 mg/kgBW. A Completely Randomized Design was used with two control groups (K+ and K−) and four treatment groups (P1–P4), totalling 18 mice with three visual-field replicates per group. The extract was administered by gavage at 0.13 mL per day for seven days. Multivariate Analysis of Variance (MANOVA) on renal parameters showed a significant concentration effect on tubular size and glomerular diameter (Wilks' Lambda = 0.011; F = 19.205; p = 0.000), with tubular size and glomerular diameter increasing proportionally with concentration, reaching 58.2% and 64.2% at P4 relative to K+. The Kruskal-Wallis test on pancreatic data was also significant (p = 0.015), and Mann-Whitney post-hoc analysis indicated that groups P3 and P4 differed significantly from K+ but not from K−. Concentrations of 75% and 100% produced histological features closest to the healthy control. Post-treatment blood glucose values for groups P1–P4 were incompletely recorded in this study, so the magnitude of glycaemic reduction cannot yet be confirmed; this gap should be closed in follow-up work before an effective concentration is recommended for the next stage of preclinical testing.]]>
