Corn silk methanolic extract improves oxidative stress and inflammatory responses in rats’ excision wound model

Anti-inflammatory and antioxidant activities of corn silk (Stigma maydis of Zea mays L.) extract were investigated in excision wound model. Twenty male Wistar rats (130-150g) were grouped into four (n=5/group): Control rats received 0.5 mL distilled water, the experimental groups received distilled water (0.5 mL), aqueous corn-silk extract (ACSE; 500 mg/kg) and methanolic corn-silk extract (MCSE; 500 mg/kg), twice/day orally, three weeks before and three weeks after they had 1.5 × 1.0 cm excision wound. Rats were sacrificed and blood was collected. Serum was separated while wound tissues were removed, homogenised and supernatant was stored. Antioxidant enzymes, malondialdehyde, hydroxyproline, cyclooxygenase-2 and NO were measured in wound tissues colorimetrically, while serum cytokines were measured using enzyme linked immunosorbent assay. MCSE significantly (p˂0.05) increased glutathione peroxidase, superoxide dismutase, catalase, hydroxyproline and total protein content but decreased significantly (p˂0.05) malondialdehyde, cyclooxygenase-2, IL-1β, TNF-α, and IFN-γ when compared with untreated wound. ACSE increased significantly (p<0.05) glutathione peroxidase and superoxide dismutase but decreased significantly (p<0.05) malondialdehyde and cyclooxygenase-2. However, it produced no significant effect on catalase, IL-1β, TNF-α, and IFN-γ when compared with untreated wound. MCSE attenuated oxidative and inflammatory responses in excision wound rat model.