Gastroprotective and Healing Effect of Naringin and Quercetin in Experimentally Induced Gastric Ulcer by Diclofenac Sodium in Adult Male Albino Rat: A Histological and Immunohistochemical Study

Introduction: Diclofenac (DFC) has been widely utilized as anti-inflammatory and analgesic medication. Naringin is a natural flavanone glycoside that is found in citrus fruits. Quercetin is a natural flavonoid found in vegetables and fruits.
Aim: evaluation of the roles of naringin and quercetin in protection and recovery of rats' stomach ulcers caused by DFC. Material and methods: Forty male albino adult rats were divided into 4 identical groups: Control group,(DFC)group < strong>: rats were given 10 mg/kg b.w. /day DFC by oral gavage for 4 weeks,(DFC + Naringin)group < strong>: rats were given100 mg/kg/body weight naringin daily along with previous dose of DFC dose for 4 weeks and(DFC + Quercetin) group < strong>: rats were given 50 mg/kg body weight quercetin daily along with previous dose of DFC. The stomach tissues were examined grossly and processed for microscopic examination.
Results: DFC group revealed ulceration of mucosa resulting in detachment of fundic mucosa, inflammatory infiltration, and wide lumen of fundic glands. There was a thin, sporadic PAS-AB mucous coating over the surface epithelium. It showed extensive iNOS immunoreaction in the cytoplasm of gastric epithelial cell and strong PCNA immuno-expression in the cells lining the fundic glands.  Both naringin and quercetin exhibited a protective effect by prevention of histopathological changes caused by DFC on gastric mucosa. There is a persistent, thick mucus coating covering the surface epithelium, weak iNOS immunoreaction and moderate PCNA.  
Conclusion: The intake of naringin during taking diclofenac protects the stomach mucosa but quercetin has more protection than naringin.