<i>Cinnamomum longepetiolatum</i> (Kosterm.) Extract Modulates Inflammatory Responses and Oxidative Stress in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages

Although inflammation is a protective response to maintain homeostasis, chronic or excessive inflammation is closely associated with various pathological conditions, including autoimmune diseases, cancer, and chronic inflammatory disorders. Therefore, the present study aimed to evaluate the anti-inflammatory activity of <i>Cinnamomum longepetiolatum</i> (Kosterm.), a medicinal plant from Vietnam, at the cellular level. Although <i>C. longepetiolatum</i> is widely used in traditional medicine, its anti-inflammatory effects remain to be fully elucidated. Herein, we investigated the effects of <i>C. longepetiolatum</i> (Kosterm.) extract (CLE) on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and explored the molecular mechanisms by which CLE exerts its inhibitory effects. The results showed that CLE significantly suppressed the messenger RNA expression levels of proinflammatory cytokines, including interleukin (IL)-1β and IL-6, and inhibited the phosphorylation of key proteins in the nuclear factor-kappa B (NF-κB) signaling pathway, including p65, NF-kappa-B inhibitor alpha, and IκB kinase-α. Moreover, CLE markedly decreased LPS-induced production of reactive oxygen species, as measured by the 2',7'-dichlorodihydrofluorescein diacetate probe. These findings demonstrate that CLE possesses strong anti-inflammatory and antioxidant effects, supporting its potential as a therapeutic candidate for the treatment of inflammatory diseases.