Haloxylon salicornicum Phytochemicals Suppress NF-κB, iNOS and Pro-inflammatory Cytokines in Lipopolysaccharide-induced Macrophages

Haloxylon salicornicum is traditionally used for the treatment of several disorders associated with inflammation. Despite it is a defense response against tissue injury and infections, inflammation can become a chronic condition that can negatively impact the body. This study investigated the effect of H. salicornicum phytochemicals nuclear factor-kappaB (NF-kappa B), inducible nitric oxide synthase (iNOS) and cytokines release by lipopolysaccharide (LPS)-challenged macrophages in vitro. The binding affinity of the tested phytochemical towards NF-kappa B and iNOS was investigated using molecular docking. Ten compounds (four coumarins, three sterols and three flavonoids) were isolated from the ethanolic extract of H. salicornicum. Treatment of LPS-challenged macrophages with the compounds resulted in remarkable decrease in NF-kappa B p65 and iNOS mRNA abundance. All compounds suppressed the production of nitric oxide (NO) and the pro-inflammatory cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-6) from macrophages challenged with LPS. Molecular docking revealed the ability of the isolated phytochemicals to bind NF-kappa B p65 and iNOS. In conclusion, H. salicornicum is a rich source of phytochemicals with anti-inflammatory properties. The anti-inflammatory efficacy of H. salicornicum phytoconstituents is mediated via their ability to modulate NF-kappa B and iNOS, and suppress the release of NO, TNF-alpha, and IL-6 from macrophages.