Cinnamaldehyde and eugenol protect against LPS‐stimulated oxidative stress and inflammation in Raw 264.7 cells

Macrophages are leukocytes that play a strategic role in immune response and can be associated with various diseases due to their effects on the inflammation process and oxidative events. The current study was evaluated the anti-inflammatory and antioxidant properties of cinnamaldehyde and eugenol, which are phyto-compounds with numerous bioactive properties, on lipopolysaccharide (LPS)-induced macrophage cells. For this purpose, Raw 264.7 cells were incubated with cinnamaldehyde or eugenol (15, 25, and 50 μM) then stimulated with LPS. After 24 hr, tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 levels (as inflammatory mediators), and malondialdehyde (MDA) and nitric oxide (NOx) levels as well as superoxide dismutase (SOD) and catalase (CAT) activities (as oxidative status markers) were determined in cell cultures. Cinnamaldehyde and eugenol pre-treatments decreased TNF-α, IL-1β, and IL-6 levels as compared to LPS group at all concentrations. Furthermore, these pre-treatments increased SOD activity while decreased MDA and NOx levels as well as CAT activity at different concentrations. Our results demonstrated that these phyto-compounds have potential for the treatment of various diseases as protective agents against chronic inflammation and oxidative stress. PRACTICAL APPLICATIONS: Chronic inflammation and oxidative stress are complications that play a detrimental role in the pathophysiology of many diseases. Alternative treatment methods have been investigated to prevent them. Cinnamaldehyde and eugenol are phyto-compounds with high bioactivity that can be obtained from foods and spices. In this study, the protective effects of cinnamaldehyde and eugenol on lipopolysaccharide-induced oxidative stress and inflammation in macrophage cells were investigated. According to the obtained results, cinnamaldehyde and eugenol pre-treatments decreased inflammation and also reduced oxidative stress. Cinnamaldehyde and eugenol may be a better natural alternative protective agent for the chronic inflammation- and oxidative stress-related diseases.