Modulation of IL-6 and VEGF by Oral and Topical Curcuma longa Extract in an Excisional Wound Model of Diabetic Wistar Rats

Diabetic wound healing is characterized by persistent inflammation and impaired angiogenesis. Curcuma longa contains curcuminoids, including curcumin, but the comparative effects of oral, topical, and combined administration remain incompletely defined. This post-test-only experimental study included 30 male Wistar rats allocated by block randomization into six groups (n=5): a healthy, non-diabetic, non-wounded physiological baseline group; a diabetic excisional wound plus hydrogel-base control; a povidone-iodine control; oral crude ethanolic Curcuma longa extract (100 mg/kg body weight); topical 10% extract hydrogel (200 mg/day); and combined oral-topical treatment. Groups G2-G6 underwent streptozotocin induction and excisional wounding. Treatments were administered once daily for six days. Serum IL-6 and skin-tissue VEGF were measured by ELISA on day 7. Serum IL-6 did not differ significantly among groups (Kruskal-Wallis, p=0.117). Skin-tissue VEGF differed significantly (one-way ANOVA, p=0.032), and the combined group had higher VEGF than the diabetic hydrogel-base control (Tukey, p=0.013); all other pairwise comparisons were non-significant. Combined oral and topical Curcuma longa extract administration was associated with higher wound-tissue VEGF, whereas serum IL-6 did not differ significantly. The findings suggest a possible pro-angiogenic effect, but require confirmation using quantitative wound-closure analysis, histology, local inflammatory markers, dose-response assessment, and longer follow-up.