Immunotoxic Assessment of Rosemary Extract

Rosmarinus officinalis L., Lamiaceae, has been used since ancient time in traditional medicine to prevent or cure several health disorders. However, the minimum rosemary concentrations to interfere with immune responses, especially in normal conditions, is still unknown. The main goal of the present study was to evaluate the impact of rosemary extracts in healthy human lymphocytes to evaluate oxidative and immunotoxicological process. The main components of rosemary extract were dereplicated as polyphenols by HPLC–DAD. Extracts induced cytotoxicity in CD4 and CD8 lymphocytes, genetic damage, and a gradual decrease of the mitotic index. Furthermore, extracts prevented oxidative stress by increasing the antioxidant power of lymphocyte cultures. Therefore, rosemary can act as an immunosuppressor by reducing non-selectively the cells involved in specific immune response as well as causing genetics damage. Graphical abstract