The effect of sodium benzoate on the expression of colon epithelial barrier components and transepithelial electrical resistance

Introduction: The increasing human population and developing industrial food production techniques to meet the growing demand for food have led to an increase in the frequency of additives used in food. Sodium benzoate has been actively used since the discovery of its antibacterial and antifungal properties in the early 1900s. This study was conducted to examine the acute effects of commonly used doses of sodium benzoate on the colonic epithelial barrier. Materials and methods: The Caco-2 cell line was chosen for simulating intestinal barrier function. Sodium benzoate was diluted at concentrations of 1/1,000 and 1/10,000 and incubated for 24 hours. After the application, TEER measurements were taken in the cultures. The levels of E-cadherin, N-cadherin, and α-SMA were measured using the Western blot method. Results: After the application of both concentrations of sodium benzoate, a significant decrease in TEER value, a significant increase in E-cadherin value, and a significant decrease in N-cadherin and α-SMA values were observed in the measurements performed at 24 hours. Conclusion: It was found that when sodium benzoate is applied at concentrations permitted for use in food, it causes a decrease in TEER in acute exposure. The decrease in TEER level was associated with a disturbance in epithelial barrier function. An increase in E-cadherin and a decrease in N-cadherin and α-SMA levels were observed as an effort to repair the disrupted barrier function. However, more detailed studies are needed to evaluate the effects of chronic and repeated exposure on the colon epithelial barrier.