The effect of individual sulfasalazine administration and in combination with esomeprazole on buccal mucosa of albino rats: histological, immunohistochemical, and molecular study

The study aims to investigate the effect of sulfasalazine (SFZN) individually and in combination with esomeprazole (ESOm) on the buccal mucosa of albino rats. SFZN is a widely used drug for the management of various autoimmune diseases which has been reported to cause renal injury in humans and a dose of 600 mg/kg/day has been described to cause renal injury in rats. ESOm is a commonly used proton pump inhibitor. Few studies have investigated their effects on oral and paraoral tissues. Three groups were designed out of 27 male albino rats. The control group was given distilled water, the SFZN group was given SFZN (600 mg/kg/day), and the ESOm group was given SFZN (600 mg/kg/day) and ESOm (30 mg/kg body weight); the drugs were dissolved in distilled water. The experiment was conducted for 14 days. Buccal mucosae were evaluated for keratin thickness, area % of iron deposition, area% of immunoreactivity to nuclear factor erythroid 2-related factor 2 (Nrf2) and glutathione (GSH) tissue level using one-way ANOVA and post hoc tests. The level of statistical significance was set at p < 0.05. SFZN individually has significantly increased keratin thickness, disrupted Nrf2 machinery and glutathione tissue level, while SFZN in combination with ESOm showed significant increase in area% of iron deposition. DNA degradation using comet assay was evaluated using Kruskal–Wallis and Dunn’s test which revealed no significant difference of tail length and tail moment in SFZN group and ESOm group but these parameters were significantly different in these two groups in relation to the control group ( p < 0.05). Graphical abstract Effect of sulfasalazine individually and in combination with esomeprazole on buccal mucosa of albino rats evaluated via morphometric analysis for keratin thickness, tissue iron deposition and immunoreactivity to Nrf2 and via molecular analysis measuring glutathione tissue level and DNA degradation (This figure has been created using BioRender.com)