Anti‐Inflammatory Activity of Novel Dehydrozingerone‐6 (DHZ‐6) Through Modulation of iNOS, COX‐2, and NF‐κB/p65 in LPS‐Stimulated Macrophages and In Vivo Acute Lung Injury Murine Model

Acute lung injury (ALI) poses a significant threat in respiratory diseases and can lead to organ failure in chronic conditions. In this study, we evaluated the preventive effects of Dehydrozingerone-6 against Lipopolysaccharide (LPS)-induced inflammation in macrophages using RAW 264.7 and in a mouse model of ALI. During preliminary screening, Dehydrozingerone-6 demonstrated significant inhibition of cytokines and maintained 97% cell viability at 10 μM. Further in vitro studies showed that Dehydrozingerone-6 effectively suppressed LPS-induced production of nitric oxide, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin-1 beta (IL-1β), and reactive oxygen species (ROS) at a concentration of 10 μM. Immunocytochemistry and Western blot analyses revealed reduced expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), Nuclear Factor kappa B (NF-κB/p65), and phosphorylated IκBα (p-IκBα). In vivo LPS-induced lung injury model revealed that Dehydrozingerone-6 protected lung tissue from degradation and significantly inhibited IL-6 and TNF-α production at a dose of 50 mg/kg. Furthermore, Dehydrozingerone-6 significantly reduced carrageenan-induced paw edema and leukocyte migration. Dehydrozingerone-6 also markedly reduced vascular permeability in an acetic acid-induced model. Toxicological studies conducted at doses up to 2000 mg/kg body weight showed no notable alterations in hematological parameters or histopathology of the liver and kidney, suggesting a favorable safety profile. Overall, Dehydrozingerone-6 exhibited strong anti-inflammatory activity in vitro as well as in vivo studies by downregulating the generation of pro-inflammatory mediators and oxidative stress through attenuation of iNOS, COX-2, and NF-κB/p65.